diff.con commit diff.c: emit_diff_symbol learns about DIFF_SYMBOL_SUMMARY (146fdb0)
   1/*
   2 * Copyright (C) 2005 Junio C Hamano
   3 */
   4#include "cache.h"
   5#include "config.h"
   6#include "tempfile.h"
   7#include "quote.h"
   8#include "diff.h"
   9#include "diffcore.h"
  10#include "delta.h"
  11#include "xdiff-interface.h"
  12#include "color.h"
  13#include "attr.h"
  14#include "run-command.h"
  15#include "utf8.h"
  16#include "userdiff.h"
  17#include "submodule-config.h"
  18#include "submodule.h"
  19#include "ll-merge.h"
  20#include "string-list.h"
  21#include "argv-array.h"
  22#include "graph.h"
  23
  24#ifdef NO_FAST_WORKING_DIRECTORY
  25#define FAST_WORKING_DIRECTORY 0
  26#else
  27#define FAST_WORKING_DIRECTORY 1
  28#endif
  29
  30static int diff_detect_rename_default;
  31static int diff_indent_heuristic = 1;
  32static int diff_rename_limit_default = 400;
  33static int diff_suppress_blank_empty;
  34static int diff_use_color_default = -1;
  35static int diff_context_default = 3;
  36static int diff_interhunk_context_default;
  37static const char *diff_word_regex_cfg;
  38static const char *external_diff_cmd_cfg;
  39static const char *diff_order_file_cfg;
  40int diff_auto_refresh_index = 1;
  41static int diff_mnemonic_prefix;
  42static int diff_no_prefix;
  43static int diff_stat_graph_width;
  44static int diff_dirstat_permille_default = 30;
  45static struct diff_options default_diff_options;
  46static long diff_algorithm;
  47static unsigned ws_error_highlight_default = WSEH_NEW;
  48
  49static char diff_colors[][COLOR_MAXLEN] = {
  50        GIT_COLOR_RESET,
  51        GIT_COLOR_NORMAL,       /* CONTEXT */
  52        GIT_COLOR_BOLD,         /* METAINFO */
  53        GIT_COLOR_CYAN,         /* FRAGINFO */
  54        GIT_COLOR_RED,          /* OLD */
  55        GIT_COLOR_GREEN,        /* NEW */
  56        GIT_COLOR_YELLOW,       /* COMMIT */
  57        GIT_COLOR_BG_RED,       /* WHITESPACE */
  58        GIT_COLOR_NORMAL,       /* FUNCINFO */
  59};
  60
  61static NORETURN void die_want_option(const char *option_name)
  62{
  63        die(_("option '%s' requires a value"), option_name);
  64}
  65
  66static int parse_diff_color_slot(const char *var)
  67{
  68        if (!strcasecmp(var, "context") || !strcasecmp(var, "plain"))
  69                return DIFF_CONTEXT;
  70        if (!strcasecmp(var, "meta"))
  71                return DIFF_METAINFO;
  72        if (!strcasecmp(var, "frag"))
  73                return DIFF_FRAGINFO;
  74        if (!strcasecmp(var, "old"))
  75                return DIFF_FILE_OLD;
  76        if (!strcasecmp(var, "new"))
  77                return DIFF_FILE_NEW;
  78        if (!strcasecmp(var, "commit"))
  79                return DIFF_COMMIT;
  80        if (!strcasecmp(var, "whitespace"))
  81                return DIFF_WHITESPACE;
  82        if (!strcasecmp(var, "func"))
  83                return DIFF_FUNCINFO;
  84        return -1;
  85}
  86
  87static int parse_dirstat_params(struct diff_options *options, const char *params_string,
  88                                struct strbuf *errmsg)
  89{
  90        char *params_copy = xstrdup(params_string);
  91        struct string_list params = STRING_LIST_INIT_NODUP;
  92        int ret = 0;
  93        int i;
  94
  95        if (*params_copy)
  96                string_list_split_in_place(&params, params_copy, ',', -1);
  97        for (i = 0; i < params.nr; i++) {
  98                const char *p = params.items[i].string;
  99                if (!strcmp(p, "changes")) {
 100                        DIFF_OPT_CLR(options, DIRSTAT_BY_LINE);
 101                        DIFF_OPT_CLR(options, DIRSTAT_BY_FILE);
 102                } else if (!strcmp(p, "lines")) {
 103                        DIFF_OPT_SET(options, DIRSTAT_BY_LINE);
 104                        DIFF_OPT_CLR(options, DIRSTAT_BY_FILE);
 105                } else if (!strcmp(p, "files")) {
 106                        DIFF_OPT_CLR(options, DIRSTAT_BY_LINE);
 107                        DIFF_OPT_SET(options, DIRSTAT_BY_FILE);
 108                } else if (!strcmp(p, "noncumulative")) {
 109                        DIFF_OPT_CLR(options, DIRSTAT_CUMULATIVE);
 110                } else if (!strcmp(p, "cumulative")) {
 111                        DIFF_OPT_SET(options, DIRSTAT_CUMULATIVE);
 112                } else if (isdigit(*p)) {
 113                        char *end;
 114                        int permille = strtoul(p, &end, 10) * 10;
 115                        if (*end == '.' && isdigit(*++end)) {
 116                                /* only use first digit */
 117                                permille += *end - '0';
 118                                /* .. and ignore any further digits */
 119                                while (isdigit(*++end))
 120                                        ; /* nothing */
 121                        }
 122                        if (!*end)
 123                                options->dirstat_permille = permille;
 124                        else {
 125                                strbuf_addf(errmsg, _("  Failed to parse dirstat cut-off percentage '%s'\n"),
 126                                            p);
 127                                ret++;
 128                        }
 129                } else {
 130                        strbuf_addf(errmsg, _("  Unknown dirstat parameter '%s'\n"), p);
 131                        ret++;
 132                }
 133
 134        }
 135        string_list_clear(&params, 0);
 136        free(params_copy);
 137        return ret;
 138}
 139
 140static int parse_submodule_params(struct diff_options *options, const char *value)
 141{
 142        if (!strcmp(value, "log"))
 143                options->submodule_format = DIFF_SUBMODULE_LOG;
 144        else if (!strcmp(value, "short"))
 145                options->submodule_format = DIFF_SUBMODULE_SHORT;
 146        else if (!strcmp(value, "diff"))
 147                options->submodule_format = DIFF_SUBMODULE_INLINE_DIFF;
 148        else
 149                return -1;
 150        return 0;
 151}
 152
 153static int git_config_rename(const char *var, const char *value)
 154{
 155        if (!value)
 156                return DIFF_DETECT_RENAME;
 157        if (!strcasecmp(value, "copies") || !strcasecmp(value, "copy"))
 158                return  DIFF_DETECT_COPY;
 159        return git_config_bool(var,value) ? DIFF_DETECT_RENAME : 0;
 160}
 161
 162long parse_algorithm_value(const char *value)
 163{
 164        if (!value)
 165                return -1;
 166        else if (!strcasecmp(value, "myers") || !strcasecmp(value, "default"))
 167                return 0;
 168        else if (!strcasecmp(value, "minimal"))
 169                return XDF_NEED_MINIMAL;
 170        else if (!strcasecmp(value, "patience"))
 171                return XDF_PATIENCE_DIFF;
 172        else if (!strcasecmp(value, "histogram"))
 173                return XDF_HISTOGRAM_DIFF;
 174        return -1;
 175}
 176
 177static int parse_one_token(const char **arg, const char *token)
 178{
 179        const char *rest;
 180        if (skip_prefix(*arg, token, &rest) && (!*rest || *rest == ',')) {
 181                *arg = rest;
 182                return 1;
 183        }
 184        return 0;
 185}
 186
 187static int parse_ws_error_highlight(const char *arg)
 188{
 189        const char *orig_arg = arg;
 190        unsigned val = 0;
 191
 192        while (*arg) {
 193                if (parse_one_token(&arg, "none"))
 194                        val = 0;
 195                else if (parse_one_token(&arg, "default"))
 196                        val = WSEH_NEW;
 197                else if (parse_one_token(&arg, "all"))
 198                        val = WSEH_NEW | WSEH_OLD | WSEH_CONTEXT;
 199                else if (parse_one_token(&arg, "new"))
 200                        val |= WSEH_NEW;
 201                else if (parse_one_token(&arg, "old"))
 202                        val |= WSEH_OLD;
 203                else if (parse_one_token(&arg, "context"))
 204                        val |= WSEH_CONTEXT;
 205                else {
 206                        return -1 - (int)(arg - orig_arg);
 207                }
 208                if (*arg)
 209                        arg++;
 210        }
 211        return val;
 212}
 213
 214/*
 215 * These are to give UI layer defaults.
 216 * The core-level commands such as git-diff-files should
 217 * never be affected by the setting of diff.renames
 218 * the user happens to have in the configuration file.
 219 */
 220void init_diff_ui_defaults(void)
 221{
 222        diff_detect_rename_default = 1;
 223}
 224
 225int git_diff_heuristic_config(const char *var, const char *value, void *cb)
 226{
 227        if (!strcmp(var, "diff.indentheuristic"))
 228                diff_indent_heuristic = git_config_bool(var, value);
 229        return 0;
 230}
 231
 232int git_diff_ui_config(const char *var, const char *value, void *cb)
 233{
 234        if (!strcmp(var, "diff.color") || !strcmp(var, "color.diff")) {
 235                diff_use_color_default = git_config_colorbool(var, value);
 236                return 0;
 237        }
 238        if (!strcmp(var, "diff.context")) {
 239                diff_context_default = git_config_int(var, value);
 240                if (diff_context_default < 0)
 241                        return -1;
 242                return 0;
 243        }
 244        if (!strcmp(var, "diff.interhunkcontext")) {
 245                diff_interhunk_context_default = git_config_int(var, value);
 246                if (diff_interhunk_context_default < 0)
 247                        return -1;
 248                return 0;
 249        }
 250        if (!strcmp(var, "diff.renames")) {
 251                diff_detect_rename_default = git_config_rename(var, value);
 252                return 0;
 253        }
 254        if (!strcmp(var, "diff.autorefreshindex")) {
 255                diff_auto_refresh_index = git_config_bool(var, value);
 256                return 0;
 257        }
 258        if (!strcmp(var, "diff.mnemonicprefix")) {
 259                diff_mnemonic_prefix = git_config_bool(var, value);
 260                return 0;
 261        }
 262        if (!strcmp(var, "diff.noprefix")) {
 263                diff_no_prefix = git_config_bool(var, value);
 264                return 0;
 265        }
 266        if (!strcmp(var, "diff.statgraphwidth")) {
 267                diff_stat_graph_width = git_config_int(var, value);
 268                return 0;
 269        }
 270        if (!strcmp(var, "diff.external"))
 271                return git_config_string(&external_diff_cmd_cfg, var, value);
 272        if (!strcmp(var, "diff.wordregex"))
 273                return git_config_string(&diff_word_regex_cfg, var, value);
 274        if (!strcmp(var, "diff.orderfile"))
 275                return git_config_pathname(&diff_order_file_cfg, var, value);
 276
 277        if (!strcmp(var, "diff.ignoresubmodules"))
 278                handle_ignore_submodules_arg(&default_diff_options, value);
 279
 280        if (!strcmp(var, "diff.submodule")) {
 281                if (parse_submodule_params(&default_diff_options, value))
 282                        warning(_("Unknown value for 'diff.submodule' config variable: '%s'"),
 283                                value);
 284                return 0;
 285        }
 286
 287        if (!strcmp(var, "diff.algorithm")) {
 288                diff_algorithm = parse_algorithm_value(value);
 289                if (diff_algorithm < 0)
 290                        return -1;
 291                return 0;
 292        }
 293
 294        if (!strcmp(var, "diff.wserrorhighlight")) {
 295                int val = parse_ws_error_highlight(value);
 296                if (val < 0)
 297                        return -1;
 298                ws_error_highlight_default = val;
 299                return 0;
 300        }
 301
 302        if (git_color_config(var, value, cb) < 0)
 303                return -1;
 304
 305        return git_diff_basic_config(var, value, cb);
 306}
 307
 308int git_diff_basic_config(const char *var, const char *value, void *cb)
 309{
 310        const char *name;
 311
 312        if (!strcmp(var, "diff.renamelimit")) {
 313                diff_rename_limit_default = git_config_int(var, value);
 314                return 0;
 315        }
 316
 317        if (userdiff_config(var, value) < 0)
 318                return -1;
 319
 320        if (skip_prefix(var, "diff.color.", &name) ||
 321            skip_prefix(var, "color.diff.", &name)) {
 322                int slot = parse_diff_color_slot(name);
 323                if (slot < 0)
 324                        return 0;
 325                if (!value)
 326                        return config_error_nonbool(var);
 327                return color_parse(value, diff_colors[slot]);
 328        }
 329
 330        /* like GNU diff's --suppress-blank-empty option  */
 331        if (!strcmp(var, "diff.suppressblankempty") ||
 332                        /* for backwards compatibility */
 333                        !strcmp(var, "diff.suppress-blank-empty")) {
 334                diff_suppress_blank_empty = git_config_bool(var, value);
 335                return 0;
 336        }
 337
 338        if (!strcmp(var, "diff.dirstat")) {
 339                struct strbuf errmsg = STRBUF_INIT;
 340                default_diff_options.dirstat_permille = diff_dirstat_permille_default;
 341                if (parse_dirstat_params(&default_diff_options, value, &errmsg))
 342                        warning(_("Found errors in 'diff.dirstat' config variable:\n%s"),
 343                                errmsg.buf);
 344                strbuf_release(&errmsg);
 345                diff_dirstat_permille_default = default_diff_options.dirstat_permille;
 346                return 0;
 347        }
 348
 349        if (starts_with(var, "submodule."))
 350                return parse_submodule_config_option(var, value);
 351
 352        if (git_diff_heuristic_config(var, value, cb) < 0)
 353                return -1;
 354
 355        return git_default_config(var, value, cb);
 356}
 357
 358static char *quote_two(const char *one, const char *two)
 359{
 360        int need_one = quote_c_style(one, NULL, NULL, 1);
 361        int need_two = quote_c_style(two, NULL, NULL, 1);
 362        struct strbuf res = STRBUF_INIT;
 363
 364        if (need_one + need_two) {
 365                strbuf_addch(&res, '"');
 366                quote_c_style(one, &res, NULL, 1);
 367                quote_c_style(two, &res, NULL, 1);
 368                strbuf_addch(&res, '"');
 369        } else {
 370                strbuf_addstr(&res, one);
 371                strbuf_addstr(&res, two);
 372        }
 373        return strbuf_detach(&res, NULL);
 374}
 375
 376static const char *external_diff(void)
 377{
 378        static const char *external_diff_cmd = NULL;
 379        static int done_preparing = 0;
 380
 381        if (done_preparing)
 382                return external_diff_cmd;
 383        external_diff_cmd = getenv("GIT_EXTERNAL_DIFF");
 384        if (!external_diff_cmd)
 385                external_diff_cmd = external_diff_cmd_cfg;
 386        done_preparing = 1;
 387        return external_diff_cmd;
 388}
 389
 390/*
 391 * Keep track of files used for diffing. Sometimes such an entry
 392 * refers to a temporary file, sometimes to an existing file, and
 393 * sometimes to "/dev/null".
 394 */
 395static struct diff_tempfile {
 396        /*
 397         * filename external diff should read from, or NULL if this
 398         * entry is currently not in use:
 399         */
 400        const char *name;
 401
 402        char hex[GIT_MAX_HEXSZ + 1];
 403        char mode[10];
 404
 405        /*
 406         * If this diff_tempfile instance refers to a temporary file,
 407         * this tempfile object is used to manage its lifetime.
 408         */
 409        struct tempfile tempfile;
 410} diff_temp[2];
 411
 412typedef unsigned long (*sane_truncate_fn)(char *line, unsigned long len);
 413
 414struct emit_callback {
 415        int color_diff;
 416        unsigned ws_rule;
 417        int blank_at_eof_in_preimage;
 418        int blank_at_eof_in_postimage;
 419        int lno_in_preimage;
 420        int lno_in_postimage;
 421        sane_truncate_fn truncate;
 422        const char **label_path;
 423        struct diff_words_data *diff_words;
 424        struct diff_options *opt;
 425        struct strbuf *header;
 426};
 427
 428static int count_lines(const char *data, int size)
 429{
 430        int count, ch, completely_empty = 1, nl_just_seen = 0;
 431        count = 0;
 432        while (0 < size--) {
 433                ch = *data++;
 434                if (ch == '\n') {
 435                        count++;
 436                        nl_just_seen = 1;
 437                        completely_empty = 0;
 438                }
 439                else {
 440                        nl_just_seen = 0;
 441                        completely_empty = 0;
 442                }
 443        }
 444        if (completely_empty)
 445                return 0;
 446        if (!nl_just_seen)
 447                count++; /* no trailing newline */
 448        return count;
 449}
 450
 451static int fill_mmfile(mmfile_t *mf, struct diff_filespec *one)
 452{
 453        if (!DIFF_FILE_VALID(one)) {
 454                mf->ptr = (char *)""; /* does not matter */
 455                mf->size = 0;
 456                return 0;
 457        }
 458        else if (diff_populate_filespec(one, 0))
 459                return -1;
 460
 461        mf->ptr = one->data;
 462        mf->size = one->size;
 463        return 0;
 464}
 465
 466/* like fill_mmfile, but only for size, so we can avoid retrieving blob */
 467static unsigned long diff_filespec_size(struct diff_filespec *one)
 468{
 469        if (!DIFF_FILE_VALID(one))
 470                return 0;
 471        diff_populate_filespec(one, CHECK_SIZE_ONLY);
 472        return one->size;
 473}
 474
 475static int count_trailing_blank(mmfile_t *mf, unsigned ws_rule)
 476{
 477        char *ptr = mf->ptr;
 478        long size = mf->size;
 479        int cnt = 0;
 480
 481        if (!size)
 482                return cnt;
 483        ptr += size - 1; /* pointing at the very end */
 484        if (*ptr != '\n')
 485                ; /* incomplete line */
 486        else
 487                ptr--; /* skip the last LF */
 488        while (mf->ptr < ptr) {
 489                char *prev_eol;
 490                for (prev_eol = ptr; mf->ptr <= prev_eol; prev_eol--)
 491                        if (*prev_eol == '\n')
 492                                break;
 493                if (!ws_blank_line(prev_eol + 1, ptr - prev_eol, ws_rule))
 494                        break;
 495                cnt++;
 496                ptr = prev_eol - 1;
 497        }
 498        return cnt;
 499}
 500
 501static void check_blank_at_eof(mmfile_t *mf1, mmfile_t *mf2,
 502                               struct emit_callback *ecbdata)
 503{
 504        int l1, l2, at;
 505        unsigned ws_rule = ecbdata->ws_rule;
 506        l1 = count_trailing_blank(mf1, ws_rule);
 507        l2 = count_trailing_blank(mf2, ws_rule);
 508        if (l2 <= l1) {
 509                ecbdata->blank_at_eof_in_preimage = 0;
 510                ecbdata->blank_at_eof_in_postimage = 0;
 511                return;
 512        }
 513        at = count_lines(mf1->ptr, mf1->size);
 514        ecbdata->blank_at_eof_in_preimage = (at - l1) + 1;
 515
 516        at = count_lines(mf2->ptr, mf2->size);
 517        ecbdata->blank_at_eof_in_postimage = (at - l2) + 1;
 518}
 519
 520static void emit_line_0(struct diff_options *o, const char *set, const char *reset,
 521                        int first, const char *line, int len)
 522{
 523        int has_trailing_newline, has_trailing_carriage_return;
 524        int nofirst;
 525        FILE *file = o->file;
 526
 527        fputs(diff_line_prefix(o), file);
 528
 529        if (len == 0) {
 530                has_trailing_newline = (first == '\n');
 531                has_trailing_carriage_return = (!has_trailing_newline &&
 532                                                (first == '\r'));
 533                nofirst = has_trailing_newline || has_trailing_carriage_return;
 534        } else {
 535                has_trailing_newline = (len > 0 && line[len-1] == '\n');
 536                if (has_trailing_newline)
 537                        len--;
 538                has_trailing_carriage_return = (len > 0 && line[len-1] == '\r');
 539                if (has_trailing_carriage_return)
 540                        len--;
 541                nofirst = 0;
 542        }
 543
 544        if (len || !nofirst) {
 545                fputs(set, file);
 546                if (!nofirst)
 547                        fputc(first, file);
 548                fwrite(line, len, 1, file);
 549                fputs(reset, file);
 550        }
 551        if (has_trailing_carriage_return)
 552                fputc('\r', file);
 553        if (has_trailing_newline)
 554                fputc('\n', file);
 555}
 556
 557static void emit_line(struct diff_options *o, const char *set, const char *reset,
 558                      const char *line, int len)
 559{
 560        emit_line_0(o, set, reset, line[0], line+1, len-1);
 561}
 562
 563enum diff_symbol {
 564        DIFF_SYMBOL_BINARY_DIFF_HEADER,
 565        DIFF_SYMBOL_BINARY_DIFF_HEADER_DELTA,
 566        DIFF_SYMBOL_BINARY_DIFF_HEADER_LITERAL,
 567        DIFF_SYMBOL_BINARY_DIFF_BODY,
 568        DIFF_SYMBOL_BINARY_DIFF_FOOTER,
 569        DIFF_SYMBOL_STATS_SUMMARY_NO_FILES,
 570        DIFF_SYMBOL_STATS_SUMMARY_ABBREV,
 571        DIFF_SYMBOL_STATS_SUMMARY_INSERTS_DELETES,
 572        DIFF_SYMBOL_STATS_LINE,
 573        DIFF_SYMBOL_WORD_DIFF,
 574        DIFF_SYMBOL_STAT_SEP,
 575        DIFF_SYMBOL_SUMMARY,
 576        DIFF_SYMBOL_SUBMODULE_ADD,
 577        DIFF_SYMBOL_SUBMODULE_DEL,
 578        DIFF_SYMBOL_SUBMODULE_UNTRACKED,
 579        DIFF_SYMBOL_SUBMODULE_MODIFIED,
 580        DIFF_SYMBOL_SUBMODULE_HEADER,
 581        DIFF_SYMBOL_SUBMODULE_ERROR,
 582        DIFF_SYMBOL_SUBMODULE_PIPETHROUGH,
 583        DIFF_SYMBOL_REWRITE_DIFF,
 584        DIFF_SYMBOL_BINARY_FILES,
 585        DIFF_SYMBOL_HEADER,
 586        DIFF_SYMBOL_FILEPAIR_PLUS,
 587        DIFF_SYMBOL_FILEPAIR_MINUS,
 588        DIFF_SYMBOL_WORDS_PORCELAIN,
 589        DIFF_SYMBOL_WORDS,
 590        DIFF_SYMBOL_CONTEXT,
 591        DIFF_SYMBOL_CONTEXT_INCOMPLETE,
 592        DIFF_SYMBOL_PLUS,
 593        DIFF_SYMBOL_MINUS,
 594        DIFF_SYMBOL_NO_LF_EOF,
 595        DIFF_SYMBOL_CONTEXT_FRAGINFO,
 596        DIFF_SYMBOL_CONTEXT_MARKER,
 597        DIFF_SYMBOL_SEPARATOR
 598};
 599/*
 600 * Flags for content lines:
 601 * 0..12 are whitespace rules
 602 * 13-15 are WSEH_NEW | WSEH_OLD | WSEH_CONTEXT
 603 * 16 is marking if the line is blank at EOF
 604 */
 605#define DIFF_SYMBOL_CONTENT_BLANK_LINE_EOF (1<<16)
 606#define DIFF_SYMBOL_CONTENT_WS_MASK (WSEH_NEW | WSEH_OLD | WSEH_CONTEXT | WS_RULE_MASK)
 607
 608static void emit_line_ws_markup(struct diff_options *o,
 609                                const char *set, const char *reset,
 610                                const char *line, int len, char sign,
 611                                unsigned ws_rule, int blank_at_eof)
 612{
 613        const char *ws = NULL;
 614
 615        if (o->ws_error_highlight & ws_rule) {
 616                ws = diff_get_color_opt(o, DIFF_WHITESPACE);
 617                if (!*ws)
 618                        ws = NULL;
 619        }
 620
 621        if (!ws)
 622                emit_line_0(o, set, reset, sign, line, len);
 623        else if (blank_at_eof)
 624                /* Blank line at EOF - paint '+' as well */
 625                emit_line_0(o, ws, reset, sign, line, len);
 626        else {
 627                /* Emit just the prefix, then the rest. */
 628                emit_line_0(o, set, reset, sign, "", 0);
 629                ws_check_emit(line, len, ws_rule,
 630                              o->file, set, reset, ws);
 631        }
 632}
 633
 634static void emit_diff_symbol(struct diff_options *o, enum diff_symbol s,
 635                             const char *line, int len, unsigned flags)
 636{
 637        static const char *nneof = " No newline at end of file\n";
 638        const char *context, *reset, *set, *meta, *fraginfo;
 639        struct strbuf sb = STRBUF_INIT;
 640        switch (s) {
 641        case DIFF_SYMBOL_NO_LF_EOF:
 642                context = diff_get_color_opt(o, DIFF_CONTEXT);
 643                reset = diff_get_color_opt(o, DIFF_RESET);
 644                putc('\n', o->file);
 645                emit_line_0(o, context, reset, '\\',
 646                            nneof, strlen(nneof));
 647                break;
 648        case DIFF_SYMBOL_SUBMODULE_HEADER:
 649        case DIFF_SYMBOL_SUBMODULE_ERROR:
 650        case DIFF_SYMBOL_SUBMODULE_PIPETHROUGH:
 651        case DIFF_SYMBOL_STATS_SUMMARY_INSERTS_DELETES:
 652        case DIFF_SYMBOL_SUMMARY:
 653        case DIFF_SYMBOL_STATS_LINE:
 654        case DIFF_SYMBOL_BINARY_DIFF_BODY:
 655        case DIFF_SYMBOL_CONTEXT_FRAGINFO:
 656                emit_line(o, "", "", line, len);
 657                break;
 658        case DIFF_SYMBOL_CONTEXT_INCOMPLETE:
 659        case DIFF_SYMBOL_CONTEXT_MARKER:
 660                context = diff_get_color_opt(o, DIFF_CONTEXT);
 661                reset = diff_get_color_opt(o, DIFF_RESET);
 662                emit_line(o, context, reset, line, len);
 663                break;
 664        case DIFF_SYMBOL_SEPARATOR:
 665                fprintf(o->file, "%s%c",
 666                        diff_line_prefix(o),
 667                        o->line_termination);
 668                break;
 669        case DIFF_SYMBOL_CONTEXT:
 670                set = diff_get_color_opt(o, DIFF_CONTEXT);
 671                reset = diff_get_color_opt(o, DIFF_RESET);
 672                emit_line_ws_markup(o, set, reset, line, len, ' ',
 673                                    flags & (DIFF_SYMBOL_CONTENT_WS_MASK), 0);
 674                break;
 675        case DIFF_SYMBOL_PLUS:
 676                set = diff_get_color_opt(o, DIFF_FILE_NEW);
 677                reset = diff_get_color_opt(o, DIFF_RESET);
 678                emit_line_ws_markup(o, set, reset, line, len, '+',
 679                                    flags & DIFF_SYMBOL_CONTENT_WS_MASK,
 680                                    flags & DIFF_SYMBOL_CONTENT_BLANK_LINE_EOF);
 681                break;
 682        case DIFF_SYMBOL_MINUS:
 683                set = diff_get_color_opt(o, DIFF_FILE_OLD);
 684                reset = diff_get_color_opt(o, DIFF_RESET);
 685                emit_line_ws_markup(o, set, reset, line, len, '-',
 686                                    flags & DIFF_SYMBOL_CONTENT_WS_MASK, 0);
 687                break;
 688        case DIFF_SYMBOL_WORDS_PORCELAIN:
 689                context = diff_get_color_opt(o, DIFF_CONTEXT);
 690                reset = diff_get_color_opt(o, DIFF_RESET);
 691                emit_line(o, context, reset, line, len);
 692                fputs("~\n", o->file);
 693                break;
 694        case DIFF_SYMBOL_WORDS:
 695                context = diff_get_color_opt(o, DIFF_CONTEXT);
 696                reset = diff_get_color_opt(o, DIFF_RESET);
 697                /*
 698                 * Skip the prefix character, if any.  With
 699                 * diff_suppress_blank_empty, there may be
 700                 * none.
 701                 */
 702                if (line[0] != '\n') {
 703                        line++;
 704                        len--;
 705                }
 706                emit_line(o, context, reset, line, len);
 707                break;
 708        case DIFF_SYMBOL_FILEPAIR_PLUS:
 709                meta = diff_get_color_opt(o, DIFF_METAINFO);
 710                reset = diff_get_color_opt(o, DIFF_RESET);
 711                fprintf(o->file, "%s%s+++ %s%s%s\n", diff_line_prefix(o), meta,
 712                        line, reset,
 713                        strchr(line, ' ') ? "\t" : "");
 714                break;
 715        case DIFF_SYMBOL_FILEPAIR_MINUS:
 716                meta = diff_get_color_opt(o, DIFF_METAINFO);
 717                reset = diff_get_color_opt(o, DIFF_RESET);
 718                fprintf(o->file, "%s%s--- %s%s%s\n", diff_line_prefix(o), meta,
 719                        line, reset,
 720                        strchr(line, ' ') ? "\t" : "");
 721                break;
 722        case DIFF_SYMBOL_BINARY_FILES:
 723        case DIFF_SYMBOL_HEADER:
 724                fprintf(o->file, "%s", line);
 725                break;
 726        case DIFF_SYMBOL_BINARY_DIFF_HEADER:
 727                fprintf(o->file, "%sGIT binary patch\n", diff_line_prefix(o));
 728                break;
 729        case DIFF_SYMBOL_BINARY_DIFF_HEADER_DELTA:
 730                fprintf(o->file, "%sdelta %s\n", diff_line_prefix(o), line);
 731                break;
 732        case DIFF_SYMBOL_BINARY_DIFF_HEADER_LITERAL:
 733                fprintf(o->file, "%sliteral %s\n", diff_line_prefix(o), line);
 734                break;
 735        case DIFF_SYMBOL_BINARY_DIFF_FOOTER:
 736                fputs(diff_line_prefix(o), o->file);
 737                fputc('\n', o->file);
 738                break;
 739        case DIFF_SYMBOL_REWRITE_DIFF:
 740                fraginfo = diff_get_color(o->use_color, DIFF_FRAGINFO);
 741                reset = diff_get_color_opt(o, DIFF_RESET);
 742                emit_line(o, fraginfo, reset, line, len);
 743                break;
 744        case DIFF_SYMBOL_SUBMODULE_ADD:
 745                set = diff_get_color_opt(o, DIFF_FILE_NEW);
 746                reset = diff_get_color_opt(o, DIFF_RESET);
 747                emit_line(o, set, reset, line, len);
 748                break;
 749        case DIFF_SYMBOL_SUBMODULE_DEL:
 750                set = diff_get_color_opt(o, DIFF_FILE_OLD);
 751                reset = diff_get_color_opt(o, DIFF_RESET);
 752                emit_line(o, set, reset, line, len);
 753                break;
 754        case DIFF_SYMBOL_SUBMODULE_UNTRACKED:
 755                fprintf(o->file, "%sSubmodule %s contains untracked content\n",
 756                        diff_line_prefix(o), line);
 757                break;
 758        case DIFF_SYMBOL_SUBMODULE_MODIFIED:
 759                fprintf(o->file, "%sSubmodule %s contains modified content\n",
 760                        diff_line_prefix(o), line);
 761                break;
 762        case DIFF_SYMBOL_STATS_SUMMARY_NO_FILES:
 763                emit_line(o, "", "", " 0 files changed\n",
 764                          strlen(" 0 files changed\n"));
 765                break;
 766        case DIFF_SYMBOL_STATS_SUMMARY_ABBREV:
 767                emit_line(o, "", "", " ...\n", strlen(" ...\n"));
 768                break;
 769        case DIFF_SYMBOL_WORD_DIFF:
 770                fprintf(o->file, "%.*s", len, line);
 771                break;
 772        case DIFF_SYMBOL_STAT_SEP:
 773                fputs(o->stat_sep, o->file);
 774                break;
 775        default:
 776                die("BUG: unknown diff symbol");
 777        }
 778        strbuf_release(&sb);
 779}
 780
 781void diff_emit_submodule_del(struct diff_options *o, const char *line)
 782{
 783        emit_diff_symbol(o, DIFF_SYMBOL_SUBMODULE_DEL, line, strlen(line), 0);
 784}
 785
 786void diff_emit_submodule_add(struct diff_options *o, const char *line)
 787{
 788        emit_diff_symbol(o, DIFF_SYMBOL_SUBMODULE_ADD, line, strlen(line), 0);
 789}
 790
 791void diff_emit_submodule_untracked(struct diff_options *o, const char *path)
 792{
 793        emit_diff_symbol(o, DIFF_SYMBOL_SUBMODULE_UNTRACKED,
 794                         path, strlen(path), 0);
 795}
 796
 797void diff_emit_submodule_modified(struct diff_options *o, const char *path)
 798{
 799        emit_diff_symbol(o, DIFF_SYMBOL_SUBMODULE_MODIFIED,
 800                         path, strlen(path), 0);
 801}
 802
 803void diff_emit_submodule_header(struct diff_options *o, const char *header)
 804{
 805        emit_diff_symbol(o, DIFF_SYMBOL_SUBMODULE_HEADER,
 806                         header, strlen(header), 0);
 807}
 808
 809void diff_emit_submodule_error(struct diff_options *o, const char *err)
 810{
 811        emit_diff_symbol(o, DIFF_SYMBOL_SUBMODULE_ERROR, err, strlen(err), 0);
 812}
 813
 814void diff_emit_submodule_pipethrough(struct diff_options *o,
 815                                     const char *line, int len)
 816{
 817        emit_diff_symbol(o, DIFF_SYMBOL_SUBMODULE_PIPETHROUGH, line, len, 0);
 818}
 819
 820static int new_blank_line_at_eof(struct emit_callback *ecbdata, const char *line, int len)
 821{
 822        if (!((ecbdata->ws_rule & WS_BLANK_AT_EOF) &&
 823              ecbdata->blank_at_eof_in_preimage &&
 824              ecbdata->blank_at_eof_in_postimage &&
 825              ecbdata->blank_at_eof_in_preimage <= ecbdata->lno_in_preimage &&
 826              ecbdata->blank_at_eof_in_postimage <= ecbdata->lno_in_postimage))
 827                return 0;
 828        return ws_blank_line(line, len, ecbdata->ws_rule);
 829}
 830
 831static void emit_add_line(const char *reset,
 832                          struct emit_callback *ecbdata,
 833                          const char *line, int len)
 834{
 835        unsigned flags = WSEH_NEW | ecbdata->ws_rule;
 836        if (new_blank_line_at_eof(ecbdata, line, len))
 837                flags |= DIFF_SYMBOL_CONTENT_BLANK_LINE_EOF;
 838
 839        emit_diff_symbol(ecbdata->opt, DIFF_SYMBOL_PLUS, line, len, flags);
 840}
 841
 842static void emit_del_line(const char *reset,
 843                          struct emit_callback *ecbdata,
 844                          const char *line, int len)
 845{
 846        unsigned flags = WSEH_OLD | ecbdata->ws_rule;
 847        emit_diff_symbol(ecbdata->opt, DIFF_SYMBOL_MINUS, line, len, flags);
 848}
 849
 850static void emit_context_line(const char *reset,
 851                              struct emit_callback *ecbdata,
 852                              const char *line, int len)
 853{
 854        unsigned flags = WSEH_CONTEXT | ecbdata->ws_rule;
 855        emit_diff_symbol(ecbdata->opt, DIFF_SYMBOL_CONTEXT, line, len, flags);
 856}
 857
 858static void emit_hunk_header(struct emit_callback *ecbdata,
 859                             const char *line, int len)
 860{
 861        const char *context = diff_get_color(ecbdata->color_diff, DIFF_CONTEXT);
 862        const char *frag = diff_get_color(ecbdata->color_diff, DIFF_FRAGINFO);
 863        const char *func = diff_get_color(ecbdata->color_diff, DIFF_FUNCINFO);
 864        const char *reset = diff_get_color(ecbdata->color_diff, DIFF_RESET);
 865        static const char atat[2] = { '@', '@' };
 866        const char *cp, *ep;
 867        struct strbuf msgbuf = STRBUF_INIT;
 868        int org_len = len;
 869        int i = 1;
 870
 871        /*
 872         * As a hunk header must begin with "@@ -<old>, +<new> @@",
 873         * it always is at least 10 bytes long.
 874         */
 875        if (len < 10 ||
 876            memcmp(line, atat, 2) ||
 877            !(ep = memmem(line + 2, len - 2, atat, 2))) {
 878                emit_diff_symbol(ecbdata->opt,
 879                                 DIFF_SYMBOL_CONTEXT_MARKER, line, len, 0);
 880                return;
 881        }
 882        ep += 2; /* skip over @@ */
 883
 884        /* The hunk header in fraginfo color */
 885        strbuf_addstr(&msgbuf, frag);
 886        strbuf_add(&msgbuf, line, ep - line);
 887        strbuf_addstr(&msgbuf, reset);
 888
 889        /*
 890         * trailing "\r\n"
 891         */
 892        for ( ; i < 3; i++)
 893                if (line[len - i] == '\r' || line[len - i] == '\n')
 894                        len--;
 895
 896        /* blank before the func header */
 897        for (cp = ep; ep - line < len; ep++)
 898                if (*ep != ' ' && *ep != '\t')
 899                        break;
 900        if (ep != cp) {
 901                strbuf_addstr(&msgbuf, context);
 902                strbuf_add(&msgbuf, cp, ep - cp);
 903                strbuf_addstr(&msgbuf, reset);
 904        }
 905
 906        if (ep < line + len) {
 907                strbuf_addstr(&msgbuf, func);
 908                strbuf_add(&msgbuf, ep, line + len - ep);
 909                strbuf_addstr(&msgbuf, reset);
 910        }
 911
 912        strbuf_add(&msgbuf, line + len, org_len - len);
 913        strbuf_complete_line(&msgbuf);
 914        emit_diff_symbol(ecbdata->opt,
 915                         DIFF_SYMBOL_CONTEXT_FRAGINFO, msgbuf.buf, msgbuf.len, 0);
 916        strbuf_release(&msgbuf);
 917}
 918
 919static struct diff_tempfile *claim_diff_tempfile(void) {
 920        int i;
 921        for (i = 0; i < ARRAY_SIZE(diff_temp); i++)
 922                if (!diff_temp[i].name)
 923                        return diff_temp + i;
 924        die("BUG: diff is failing to clean up its tempfiles");
 925}
 926
 927static void remove_tempfile(void)
 928{
 929        int i;
 930        for (i = 0; i < ARRAY_SIZE(diff_temp); i++) {
 931                if (is_tempfile_active(&diff_temp[i].tempfile))
 932                        delete_tempfile(&diff_temp[i].tempfile);
 933                diff_temp[i].name = NULL;
 934        }
 935}
 936
 937static void add_line_count(struct strbuf *out, int count)
 938{
 939        switch (count) {
 940        case 0:
 941                strbuf_addstr(out, "0,0");
 942                break;
 943        case 1:
 944                strbuf_addstr(out, "1");
 945                break;
 946        default:
 947                strbuf_addf(out, "1,%d", count);
 948                break;
 949        }
 950}
 951
 952static void emit_rewrite_lines(struct emit_callback *ecb,
 953                               int prefix, const char *data, int size)
 954{
 955        const char *endp = NULL;
 956        const char *reset = diff_get_color(ecb->color_diff, DIFF_RESET);
 957
 958        while (0 < size) {
 959                int len;
 960
 961                endp = memchr(data, '\n', size);
 962                len = endp ? (endp - data + 1) : size;
 963                if (prefix != '+') {
 964                        ecb->lno_in_preimage++;
 965                        emit_del_line(reset, ecb, data, len);
 966                } else {
 967                        ecb->lno_in_postimage++;
 968                        emit_add_line(reset, ecb, data, len);
 969                }
 970                size -= len;
 971                data += len;
 972        }
 973        if (!endp)
 974                emit_diff_symbol(ecb->opt, DIFF_SYMBOL_NO_LF_EOF, NULL, 0, 0);
 975}
 976
 977static void emit_rewrite_diff(const char *name_a,
 978                              const char *name_b,
 979                              struct diff_filespec *one,
 980                              struct diff_filespec *two,
 981                              struct userdiff_driver *textconv_one,
 982                              struct userdiff_driver *textconv_two,
 983                              struct diff_options *o)
 984{
 985        int lc_a, lc_b;
 986        static struct strbuf a_name = STRBUF_INIT, b_name = STRBUF_INIT;
 987        const char *a_prefix, *b_prefix;
 988        char *data_one, *data_two;
 989        size_t size_one, size_two;
 990        struct emit_callback ecbdata;
 991        struct strbuf out = STRBUF_INIT;
 992
 993        if (diff_mnemonic_prefix && DIFF_OPT_TST(o, REVERSE_DIFF)) {
 994                a_prefix = o->b_prefix;
 995                b_prefix = o->a_prefix;
 996        } else {
 997                a_prefix = o->a_prefix;
 998                b_prefix = o->b_prefix;
 999        }
1000
1001        name_a += (*name_a == '/');
1002        name_b += (*name_b == '/');
1003
1004        strbuf_reset(&a_name);
1005        strbuf_reset(&b_name);
1006        quote_two_c_style(&a_name, a_prefix, name_a, 0);
1007        quote_two_c_style(&b_name, b_prefix, name_b, 0);
1008
1009        size_one = fill_textconv(textconv_one, one, &data_one);
1010        size_two = fill_textconv(textconv_two, two, &data_two);
1011
1012        memset(&ecbdata, 0, sizeof(ecbdata));
1013        ecbdata.color_diff = want_color(o->use_color);
1014        ecbdata.ws_rule = whitespace_rule(name_b);
1015        ecbdata.opt = o;
1016        if (ecbdata.ws_rule & WS_BLANK_AT_EOF) {
1017                mmfile_t mf1, mf2;
1018                mf1.ptr = (char *)data_one;
1019                mf2.ptr = (char *)data_two;
1020                mf1.size = size_one;
1021                mf2.size = size_two;
1022                check_blank_at_eof(&mf1, &mf2, &ecbdata);
1023        }
1024        ecbdata.lno_in_preimage = 1;
1025        ecbdata.lno_in_postimage = 1;
1026
1027        lc_a = count_lines(data_one, size_one);
1028        lc_b = count_lines(data_two, size_two);
1029
1030        emit_diff_symbol(o, DIFF_SYMBOL_FILEPAIR_MINUS,
1031                         a_name.buf, a_name.len, 0);
1032        emit_diff_symbol(o, DIFF_SYMBOL_FILEPAIR_PLUS,
1033                         b_name.buf, b_name.len, 0);
1034
1035        strbuf_addstr(&out, "@@ -");
1036        if (!o->irreversible_delete)
1037                add_line_count(&out, lc_a);
1038        else
1039                strbuf_addstr(&out, "?,?");
1040        strbuf_addstr(&out, " +");
1041        add_line_count(&out, lc_b);
1042        strbuf_addstr(&out, " @@\n");
1043        emit_diff_symbol(o, DIFF_SYMBOL_REWRITE_DIFF, out.buf, out.len, 0);
1044        strbuf_release(&out);
1045
1046        if (lc_a && !o->irreversible_delete)
1047                emit_rewrite_lines(&ecbdata, '-', data_one, size_one);
1048        if (lc_b)
1049                emit_rewrite_lines(&ecbdata, '+', data_two, size_two);
1050        if (textconv_one)
1051                free((char *)data_one);
1052        if (textconv_two)
1053                free((char *)data_two);
1054}
1055
1056struct diff_words_buffer {
1057        mmfile_t text;
1058        long alloc;
1059        struct diff_words_orig {
1060                const char *begin, *end;
1061        } *orig;
1062        int orig_nr, orig_alloc;
1063};
1064
1065static void diff_words_append(char *line, unsigned long len,
1066                struct diff_words_buffer *buffer)
1067{
1068        ALLOC_GROW(buffer->text.ptr, buffer->text.size + len, buffer->alloc);
1069        line++;
1070        len--;
1071        memcpy(buffer->text.ptr + buffer->text.size, line, len);
1072        buffer->text.size += len;
1073        buffer->text.ptr[buffer->text.size] = '\0';
1074}
1075
1076struct diff_words_style_elem {
1077        const char *prefix;
1078        const char *suffix;
1079        const char *color; /* NULL; filled in by the setup code if
1080                            * color is enabled */
1081};
1082
1083struct diff_words_style {
1084        enum diff_words_type type;
1085        struct diff_words_style_elem new, old, ctx;
1086        const char *newline;
1087};
1088
1089static struct diff_words_style diff_words_styles[] = {
1090        { DIFF_WORDS_PORCELAIN, {"+", "\n"}, {"-", "\n"}, {" ", "\n"}, "~\n" },
1091        { DIFF_WORDS_PLAIN, {"{+", "+}"}, {"[-", "-]"}, {"", ""}, "\n" },
1092        { DIFF_WORDS_COLOR, {"", ""}, {"", ""}, {"", ""}, "\n" }
1093};
1094
1095struct diff_words_data {
1096        struct diff_words_buffer minus, plus;
1097        const char *current_plus;
1098        int last_minus;
1099        struct diff_options *opt;
1100        regex_t *word_regex;
1101        enum diff_words_type type;
1102        struct diff_words_style *style;
1103};
1104
1105static int fn_out_diff_words_write_helper(struct diff_options *o,
1106                                          struct diff_words_style_elem *st_el,
1107                                          const char *newline,
1108                                          size_t count, const char *buf)
1109{
1110        int print = 0;
1111        struct strbuf sb = STRBUF_INIT;
1112
1113        while (count) {
1114                char *p = memchr(buf, '\n', count);
1115                if (print)
1116                        strbuf_addstr(&sb, diff_line_prefix(o));
1117
1118                if (p != buf) {
1119                        const char *reset = st_el->color && *st_el->color ?
1120                                            GIT_COLOR_RESET : NULL;
1121                        if (st_el->color && *st_el->color)
1122                                strbuf_addstr(&sb, st_el->color);
1123                        strbuf_addstr(&sb, st_el->prefix);
1124                        strbuf_add(&sb, buf, p ? p - buf : count);
1125                        strbuf_addstr(&sb, st_el->suffix);
1126                        if (reset)
1127                                strbuf_addstr(&sb, reset);
1128                }
1129                if (!p)
1130                        goto out;
1131
1132                strbuf_addstr(&sb, newline);
1133                count -= p + 1 - buf;
1134                buf = p + 1;
1135                print = 1;
1136                if (count) {
1137                        emit_diff_symbol(o, DIFF_SYMBOL_WORD_DIFF,
1138                                         sb.buf, sb.len, 0);
1139                        strbuf_reset(&sb);
1140                }
1141        }
1142
1143out:
1144        if (sb.len)
1145                emit_diff_symbol(o, DIFF_SYMBOL_WORD_DIFF,
1146                                 sb.buf, sb.len, 0);
1147        strbuf_release(&sb);
1148        return 0;
1149}
1150
1151/*
1152 * '--color-words' algorithm can be described as:
1153 *
1154 *   1. collect the minus/plus lines of a diff hunk, divided into
1155 *      minus-lines and plus-lines;
1156 *
1157 *   2. break both minus-lines and plus-lines into words and
1158 *      place them into two mmfile_t with one word for each line;
1159 *
1160 *   3. use xdiff to run diff on the two mmfile_t to get the words level diff;
1161 *
1162 * And for the common parts of the both file, we output the plus side text.
1163 * diff_words->current_plus is used to trace the current position of the plus file
1164 * which printed. diff_words->last_minus is used to trace the last minus word
1165 * printed.
1166 *
1167 * For '--graph' to work with '--color-words', we need to output the graph prefix
1168 * on each line of color words output. Generally, there are two conditions on
1169 * which we should output the prefix.
1170 *
1171 *   1. diff_words->last_minus == 0 &&
1172 *      diff_words->current_plus == diff_words->plus.text.ptr
1173 *
1174 *      that is: the plus text must start as a new line, and if there is no minus
1175 *      word printed, a graph prefix must be printed.
1176 *
1177 *   2. diff_words->current_plus > diff_words->plus.text.ptr &&
1178 *      *(diff_words->current_plus - 1) == '\n'
1179 *
1180 *      that is: a graph prefix must be printed following a '\n'
1181 */
1182static int color_words_output_graph_prefix(struct diff_words_data *diff_words)
1183{
1184        if ((diff_words->last_minus == 0 &&
1185                diff_words->current_plus == diff_words->plus.text.ptr) ||
1186                (diff_words->current_plus > diff_words->plus.text.ptr &&
1187                *(diff_words->current_plus - 1) == '\n')) {
1188                return 1;
1189        } else {
1190                return 0;
1191        }
1192}
1193
1194static void fn_out_diff_words_aux(void *priv, char *line, unsigned long len)
1195{
1196        struct diff_words_data *diff_words = priv;
1197        struct diff_words_style *style = diff_words->style;
1198        int minus_first, minus_len, plus_first, plus_len;
1199        const char *minus_begin, *minus_end, *plus_begin, *plus_end;
1200        struct diff_options *opt = diff_words->opt;
1201        const char *line_prefix;
1202
1203        if (line[0] != '@' || parse_hunk_header(line, len,
1204                        &minus_first, &minus_len, &plus_first, &plus_len))
1205                return;
1206
1207        assert(opt);
1208        line_prefix = diff_line_prefix(opt);
1209
1210        /* POSIX requires that first be decremented by one if len == 0... */
1211        if (minus_len) {
1212                minus_begin = diff_words->minus.orig[minus_first].begin;
1213                minus_end =
1214                        diff_words->minus.orig[minus_first + minus_len - 1].end;
1215        } else
1216                minus_begin = minus_end =
1217                        diff_words->minus.orig[minus_first].end;
1218
1219        if (plus_len) {
1220                plus_begin = diff_words->plus.orig[plus_first].begin;
1221                plus_end = diff_words->plus.orig[plus_first + plus_len - 1].end;
1222        } else
1223                plus_begin = plus_end = diff_words->plus.orig[plus_first].end;
1224
1225        if (color_words_output_graph_prefix(diff_words)) {
1226                fputs(line_prefix, diff_words->opt->file);
1227        }
1228        if (diff_words->current_plus != plus_begin) {
1229                fn_out_diff_words_write_helper(diff_words->opt,
1230                                &style->ctx, style->newline,
1231                                plus_begin - diff_words->current_plus,
1232                                diff_words->current_plus);
1233        }
1234        if (minus_begin != minus_end) {
1235                fn_out_diff_words_write_helper(diff_words->opt,
1236                                &style->old, style->newline,
1237                                minus_end - minus_begin, minus_begin);
1238        }
1239        if (plus_begin != plus_end) {
1240                fn_out_diff_words_write_helper(diff_words->opt,
1241                                &style->new, style->newline,
1242                                plus_end - plus_begin, plus_begin);
1243        }
1244
1245        diff_words->current_plus = plus_end;
1246        diff_words->last_minus = minus_first;
1247}
1248
1249/* This function starts looking at *begin, and returns 0 iff a word was found. */
1250static int find_word_boundaries(mmfile_t *buffer, regex_t *word_regex,
1251                int *begin, int *end)
1252{
1253        if (word_regex && *begin < buffer->size) {
1254                regmatch_t match[1];
1255                if (!regexec_buf(word_regex, buffer->ptr + *begin,
1256                                 buffer->size - *begin, 1, match, 0)) {
1257                        char *p = memchr(buffer->ptr + *begin + match[0].rm_so,
1258                                        '\n', match[0].rm_eo - match[0].rm_so);
1259                        *end = p ? p - buffer->ptr : match[0].rm_eo + *begin;
1260                        *begin += match[0].rm_so;
1261                        return *begin >= *end;
1262                }
1263                return -1;
1264        }
1265
1266        /* find the next word */
1267        while (*begin < buffer->size && isspace(buffer->ptr[*begin]))
1268                (*begin)++;
1269        if (*begin >= buffer->size)
1270                return -1;
1271
1272        /* find the end of the word */
1273        *end = *begin + 1;
1274        while (*end < buffer->size && !isspace(buffer->ptr[*end]))
1275                (*end)++;
1276
1277        return 0;
1278}
1279
1280/*
1281 * This function splits the words in buffer->text, stores the list with
1282 * newline separator into out, and saves the offsets of the original words
1283 * in buffer->orig.
1284 */
1285static void diff_words_fill(struct diff_words_buffer *buffer, mmfile_t *out,
1286                regex_t *word_regex)
1287{
1288        int i, j;
1289        long alloc = 0;
1290
1291        out->size = 0;
1292        out->ptr = NULL;
1293
1294        /* fake an empty "0th" word */
1295        ALLOC_GROW(buffer->orig, 1, buffer->orig_alloc);
1296        buffer->orig[0].begin = buffer->orig[0].end = buffer->text.ptr;
1297        buffer->orig_nr = 1;
1298
1299        for (i = 0; i < buffer->text.size; i++) {
1300                if (find_word_boundaries(&buffer->text, word_regex, &i, &j))
1301                        return;
1302
1303                /* store original boundaries */
1304                ALLOC_GROW(buffer->orig, buffer->orig_nr + 1,
1305                                buffer->orig_alloc);
1306                buffer->orig[buffer->orig_nr].begin = buffer->text.ptr + i;
1307                buffer->orig[buffer->orig_nr].end = buffer->text.ptr + j;
1308                buffer->orig_nr++;
1309
1310                /* store one word */
1311                ALLOC_GROW(out->ptr, out->size + j - i + 1, alloc);
1312                memcpy(out->ptr + out->size, buffer->text.ptr + i, j - i);
1313                out->ptr[out->size + j - i] = '\n';
1314                out->size += j - i + 1;
1315
1316                i = j - 1;
1317        }
1318}
1319
1320/* this executes the word diff on the accumulated buffers */
1321static void diff_words_show(struct diff_words_data *diff_words)
1322{
1323        xpparam_t xpp;
1324        xdemitconf_t xecfg;
1325        mmfile_t minus, plus;
1326        struct diff_words_style *style = diff_words->style;
1327
1328        struct diff_options *opt = diff_words->opt;
1329        const char *line_prefix;
1330
1331        assert(opt);
1332        line_prefix = diff_line_prefix(opt);
1333
1334        /* special case: only removal */
1335        if (!diff_words->plus.text.size) {
1336                emit_diff_symbol(diff_words->opt, DIFF_SYMBOL_WORD_DIFF,
1337                                 line_prefix, strlen(line_prefix), 0);
1338                fn_out_diff_words_write_helper(diff_words->opt,
1339                        &style->old, style->newline,
1340                        diff_words->minus.text.size,
1341                        diff_words->minus.text.ptr);
1342                diff_words->minus.text.size = 0;
1343                return;
1344        }
1345
1346        diff_words->current_plus = diff_words->plus.text.ptr;
1347        diff_words->last_minus = 0;
1348
1349        memset(&xpp, 0, sizeof(xpp));
1350        memset(&xecfg, 0, sizeof(xecfg));
1351        diff_words_fill(&diff_words->minus, &minus, diff_words->word_regex);
1352        diff_words_fill(&diff_words->plus, &plus, diff_words->word_regex);
1353        xpp.flags = 0;
1354        /* as only the hunk header will be parsed, we need a 0-context */
1355        xecfg.ctxlen = 0;
1356        if (xdi_diff_outf(&minus, &plus, fn_out_diff_words_aux, diff_words,
1357                          &xpp, &xecfg))
1358                die("unable to generate word diff");
1359        free(minus.ptr);
1360        free(plus.ptr);
1361        if (diff_words->current_plus != diff_words->plus.text.ptr +
1362                        diff_words->plus.text.size) {
1363                if (color_words_output_graph_prefix(diff_words))
1364                        emit_diff_symbol(diff_words->opt, DIFF_SYMBOL_WORD_DIFF,
1365                                         line_prefix, strlen(line_prefix), 0);
1366                fn_out_diff_words_write_helper(diff_words->opt,
1367                        &style->ctx, style->newline,
1368                        diff_words->plus.text.ptr + diff_words->plus.text.size
1369                        - diff_words->current_plus, diff_words->current_plus);
1370        }
1371        diff_words->minus.text.size = diff_words->plus.text.size = 0;
1372}
1373
1374/* In "color-words" mode, show word-diff of words accumulated in the buffer */
1375static void diff_words_flush(struct emit_callback *ecbdata)
1376{
1377        if (ecbdata->diff_words->minus.text.size ||
1378            ecbdata->diff_words->plus.text.size)
1379                diff_words_show(ecbdata->diff_words);
1380}
1381
1382static void diff_filespec_load_driver(struct diff_filespec *one)
1383{
1384        /* Use already-loaded driver */
1385        if (one->driver)
1386                return;
1387
1388        if (S_ISREG(one->mode))
1389                one->driver = userdiff_find_by_path(one->path);
1390
1391        /* Fallback to default settings */
1392        if (!one->driver)
1393                one->driver = userdiff_find_by_name("default");
1394}
1395
1396static const char *userdiff_word_regex(struct diff_filespec *one)
1397{
1398        diff_filespec_load_driver(one);
1399        return one->driver->word_regex;
1400}
1401
1402static void init_diff_words_data(struct emit_callback *ecbdata,
1403                                 struct diff_options *orig_opts,
1404                                 struct diff_filespec *one,
1405                                 struct diff_filespec *two)
1406{
1407        int i;
1408        struct diff_options *o = xmalloc(sizeof(struct diff_options));
1409        memcpy(o, orig_opts, sizeof(struct diff_options));
1410
1411        ecbdata->diff_words =
1412                xcalloc(1, sizeof(struct diff_words_data));
1413        ecbdata->diff_words->type = o->word_diff;
1414        ecbdata->diff_words->opt = o;
1415        if (!o->word_regex)
1416                o->word_regex = userdiff_word_regex(one);
1417        if (!o->word_regex)
1418                o->word_regex = userdiff_word_regex(two);
1419        if (!o->word_regex)
1420                o->word_regex = diff_word_regex_cfg;
1421        if (o->word_regex) {
1422                ecbdata->diff_words->word_regex = (regex_t *)
1423                        xmalloc(sizeof(regex_t));
1424                if (regcomp(ecbdata->diff_words->word_regex,
1425                            o->word_regex,
1426                            REG_EXTENDED | REG_NEWLINE))
1427                        die ("Invalid regular expression: %s",
1428                             o->word_regex);
1429        }
1430        for (i = 0; i < ARRAY_SIZE(diff_words_styles); i++) {
1431                if (o->word_diff == diff_words_styles[i].type) {
1432                        ecbdata->diff_words->style =
1433                                &diff_words_styles[i];
1434                        break;
1435                }
1436        }
1437        if (want_color(o->use_color)) {
1438                struct diff_words_style *st = ecbdata->diff_words->style;
1439                st->old.color = diff_get_color_opt(o, DIFF_FILE_OLD);
1440                st->new.color = diff_get_color_opt(o, DIFF_FILE_NEW);
1441                st->ctx.color = diff_get_color_opt(o, DIFF_CONTEXT);
1442        }
1443}
1444
1445static void free_diff_words_data(struct emit_callback *ecbdata)
1446{
1447        if (ecbdata->diff_words) {
1448                diff_words_flush(ecbdata);
1449                free (ecbdata->diff_words->opt);
1450                free (ecbdata->diff_words->minus.text.ptr);
1451                free (ecbdata->diff_words->minus.orig);
1452                free (ecbdata->diff_words->plus.text.ptr);
1453                free (ecbdata->diff_words->plus.orig);
1454                if (ecbdata->diff_words->word_regex) {
1455                        regfree(ecbdata->diff_words->word_regex);
1456                        free(ecbdata->diff_words->word_regex);
1457                }
1458                FREE_AND_NULL(ecbdata->diff_words);
1459        }
1460}
1461
1462const char *diff_get_color(int diff_use_color, enum color_diff ix)
1463{
1464        if (want_color(diff_use_color))
1465                return diff_colors[ix];
1466        return "";
1467}
1468
1469const char *diff_line_prefix(struct diff_options *opt)
1470{
1471        struct strbuf *msgbuf;
1472        if (!opt->output_prefix)
1473                return "";
1474
1475        msgbuf = opt->output_prefix(opt, opt->output_prefix_data);
1476        return msgbuf->buf;
1477}
1478
1479static unsigned long sane_truncate_line(struct emit_callback *ecb, char *line, unsigned long len)
1480{
1481        const char *cp;
1482        unsigned long allot;
1483        size_t l = len;
1484
1485        if (ecb->truncate)
1486                return ecb->truncate(line, len);
1487        cp = line;
1488        allot = l;
1489        while (0 < l) {
1490                (void) utf8_width(&cp, &l);
1491                if (!cp)
1492                        break; /* truncated in the middle? */
1493        }
1494        return allot - l;
1495}
1496
1497static void find_lno(const char *line, struct emit_callback *ecbdata)
1498{
1499        const char *p;
1500        ecbdata->lno_in_preimage = 0;
1501        ecbdata->lno_in_postimage = 0;
1502        p = strchr(line, '-');
1503        if (!p)
1504                return; /* cannot happen */
1505        ecbdata->lno_in_preimage = strtol(p + 1, NULL, 10);
1506        p = strchr(p, '+');
1507        if (!p)
1508                return; /* cannot happen */
1509        ecbdata->lno_in_postimage = strtol(p + 1, NULL, 10);
1510}
1511
1512static void fn_out_consume(void *priv, char *line, unsigned long len)
1513{
1514        struct emit_callback *ecbdata = priv;
1515        const char *reset = diff_get_color(ecbdata->color_diff, DIFF_RESET);
1516        struct diff_options *o = ecbdata->opt;
1517
1518        o->found_changes = 1;
1519
1520        if (ecbdata->header) {
1521                emit_diff_symbol(o, DIFF_SYMBOL_HEADER,
1522                                 ecbdata->header->buf, ecbdata->header->len, 0);
1523                strbuf_reset(ecbdata->header);
1524                ecbdata->header = NULL;
1525        }
1526
1527        if (ecbdata->label_path[0]) {
1528                emit_diff_symbol(o, DIFF_SYMBOL_FILEPAIR_MINUS,
1529                                 ecbdata->label_path[0],
1530                                 strlen(ecbdata->label_path[0]), 0);
1531                emit_diff_symbol(o, DIFF_SYMBOL_FILEPAIR_PLUS,
1532                                 ecbdata->label_path[1],
1533                                 strlen(ecbdata->label_path[1]), 0);
1534                ecbdata->label_path[0] = ecbdata->label_path[1] = NULL;
1535        }
1536
1537        if (diff_suppress_blank_empty
1538            && len == 2 && line[0] == ' ' && line[1] == '\n') {
1539                line[0] = '\n';
1540                len = 1;
1541        }
1542
1543        if (line[0] == '@') {
1544                if (ecbdata->diff_words)
1545                        diff_words_flush(ecbdata);
1546                len = sane_truncate_line(ecbdata, line, len);
1547                find_lno(line, ecbdata);
1548                emit_hunk_header(ecbdata, line, len);
1549                return;
1550        }
1551
1552        if (ecbdata->diff_words) {
1553                enum diff_symbol s =
1554                        ecbdata->diff_words->type == DIFF_WORDS_PORCELAIN ?
1555                        DIFF_SYMBOL_WORDS_PORCELAIN : DIFF_SYMBOL_WORDS;
1556                if (line[0] == '-') {
1557                        diff_words_append(line, len,
1558                                          &ecbdata->diff_words->minus);
1559                        return;
1560                } else if (line[0] == '+') {
1561                        diff_words_append(line, len,
1562                                          &ecbdata->diff_words->plus);
1563                        return;
1564                } else if (starts_with(line, "\\ ")) {
1565                        /*
1566                         * Eat the "no newline at eof" marker as if we
1567                         * saw a "+" or "-" line with nothing on it,
1568                         * and return without diff_words_flush() to
1569                         * defer processing. If this is the end of
1570                         * preimage, more "+" lines may come after it.
1571                         */
1572                        return;
1573                }
1574                diff_words_flush(ecbdata);
1575                emit_diff_symbol(o, s, line, len, 0);
1576                return;
1577        }
1578
1579        switch (line[0]) {
1580        case '+':
1581                ecbdata->lno_in_postimage++;
1582                emit_add_line(reset, ecbdata, line + 1, len - 1);
1583                break;
1584        case '-':
1585                ecbdata->lno_in_preimage++;
1586                emit_del_line(reset, ecbdata, line + 1, len - 1);
1587                break;
1588        case ' ':
1589                ecbdata->lno_in_postimage++;
1590                ecbdata->lno_in_preimage++;
1591                emit_context_line(reset, ecbdata, line + 1, len - 1);
1592                break;
1593        default:
1594                /* incomplete line at the end */
1595                ecbdata->lno_in_preimage++;
1596                emit_diff_symbol(o, DIFF_SYMBOL_CONTEXT_INCOMPLETE,
1597                                 line, len, 0);
1598                break;
1599        }
1600}
1601
1602static char *pprint_rename(const char *a, const char *b)
1603{
1604        const char *old = a;
1605        const char *new = b;
1606        struct strbuf name = STRBUF_INIT;
1607        int pfx_length, sfx_length;
1608        int pfx_adjust_for_slash;
1609        int len_a = strlen(a);
1610        int len_b = strlen(b);
1611        int a_midlen, b_midlen;
1612        int qlen_a = quote_c_style(a, NULL, NULL, 0);
1613        int qlen_b = quote_c_style(b, NULL, NULL, 0);
1614
1615        if (qlen_a || qlen_b) {
1616                quote_c_style(a, &name, NULL, 0);
1617                strbuf_addstr(&name, " => ");
1618                quote_c_style(b, &name, NULL, 0);
1619                return strbuf_detach(&name, NULL);
1620        }
1621
1622        /* Find common prefix */
1623        pfx_length = 0;
1624        while (*old && *new && *old == *new) {
1625                if (*old == '/')
1626                        pfx_length = old - a + 1;
1627                old++;
1628                new++;
1629        }
1630
1631        /* Find common suffix */
1632        old = a + len_a;
1633        new = b + len_b;
1634        sfx_length = 0;
1635        /*
1636         * If there is a common prefix, it must end in a slash.  In
1637         * that case we let this loop run 1 into the prefix to see the
1638         * same slash.
1639         *
1640         * If there is no common prefix, we cannot do this as it would
1641         * underrun the input strings.
1642         */
1643        pfx_adjust_for_slash = (pfx_length ? 1 : 0);
1644        while (a + pfx_length - pfx_adjust_for_slash <= old &&
1645               b + pfx_length - pfx_adjust_for_slash <= new &&
1646               *old == *new) {
1647                if (*old == '/')
1648                        sfx_length = len_a - (old - a);
1649                old--;
1650                new--;
1651        }
1652
1653        /*
1654         * pfx{mid-a => mid-b}sfx
1655         * {pfx-a => pfx-b}sfx
1656         * pfx{sfx-a => sfx-b}
1657         * name-a => name-b
1658         */
1659        a_midlen = len_a - pfx_length - sfx_length;
1660        b_midlen = len_b - pfx_length - sfx_length;
1661        if (a_midlen < 0)
1662                a_midlen = 0;
1663        if (b_midlen < 0)
1664                b_midlen = 0;
1665
1666        strbuf_grow(&name, pfx_length + a_midlen + b_midlen + sfx_length + 7);
1667        if (pfx_length + sfx_length) {
1668                strbuf_add(&name, a, pfx_length);
1669                strbuf_addch(&name, '{');
1670        }
1671        strbuf_add(&name, a + pfx_length, a_midlen);
1672        strbuf_addstr(&name, " => ");
1673        strbuf_add(&name, b + pfx_length, b_midlen);
1674        if (pfx_length + sfx_length) {
1675                strbuf_addch(&name, '}');
1676                strbuf_add(&name, a + len_a - sfx_length, sfx_length);
1677        }
1678        return strbuf_detach(&name, NULL);
1679}
1680
1681struct diffstat_t {
1682        int nr;
1683        int alloc;
1684        struct diffstat_file {
1685                char *from_name;
1686                char *name;
1687                char *print_name;
1688                unsigned is_unmerged:1;
1689                unsigned is_binary:1;
1690                unsigned is_renamed:1;
1691                unsigned is_interesting:1;
1692                uintmax_t added, deleted;
1693        } **files;
1694};
1695
1696static struct diffstat_file *diffstat_add(struct diffstat_t *diffstat,
1697                                          const char *name_a,
1698                                          const char *name_b)
1699{
1700        struct diffstat_file *x;
1701        x = xcalloc(1, sizeof(*x));
1702        ALLOC_GROW(diffstat->files, diffstat->nr + 1, diffstat->alloc);
1703        diffstat->files[diffstat->nr++] = x;
1704        if (name_b) {
1705                x->from_name = xstrdup(name_a);
1706                x->name = xstrdup(name_b);
1707                x->is_renamed = 1;
1708        }
1709        else {
1710                x->from_name = NULL;
1711                x->name = xstrdup(name_a);
1712        }
1713        return x;
1714}
1715
1716static void diffstat_consume(void *priv, char *line, unsigned long len)
1717{
1718        struct diffstat_t *diffstat = priv;
1719        struct diffstat_file *x = diffstat->files[diffstat->nr - 1];
1720
1721        if (line[0] == '+')
1722                x->added++;
1723        else if (line[0] == '-')
1724                x->deleted++;
1725}
1726
1727const char mime_boundary_leader[] = "------------";
1728
1729static int scale_linear(int it, int width, int max_change)
1730{
1731        if (!it)
1732                return 0;
1733        /*
1734         * make sure that at least one '-' or '+' is printed if
1735         * there is any change to this path. The easiest way is to
1736         * scale linearly as if the alloted width is one column shorter
1737         * than it is, and then add 1 to the result.
1738         */
1739        return 1 + (it * (width - 1) / max_change);
1740}
1741
1742static void show_graph(struct strbuf *out, char ch, int cnt,
1743                       const char *set, const char *reset)
1744{
1745        if (cnt <= 0)
1746                return;
1747        strbuf_addstr(out, set);
1748        strbuf_addchars(out, ch, cnt);
1749        strbuf_addstr(out, reset);
1750}
1751
1752static void fill_print_name(struct diffstat_file *file)
1753{
1754        char *pname;
1755
1756        if (file->print_name)
1757                return;
1758
1759        if (!file->is_renamed) {
1760                struct strbuf buf = STRBUF_INIT;
1761                if (quote_c_style(file->name, &buf, NULL, 0)) {
1762                        pname = strbuf_detach(&buf, NULL);
1763                } else {
1764                        pname = file->name;
1765                        strbuf_release(&buf);
1766                }
1767        } else {
1768                pname = pprint_rename(file->from_name, file->name);
1769        }
1770        file->print_name = pname;
1771}
1772
1773static void print_stat_summary_inserts_deletes(struct diff_options *options,
1774                int files, int insertions, int deletions)
1775{
1776        struct strbuf sb = STRBUF_INIT;
1777
1778        if (!files) {
1779                assert(insertions == 0 && deletions == 0);
1780                emit_diff_symbol(options, DIFF_SYMBOL_STATS_SUMMARY_NO_FILES,
1781                                 NULL, 0, 0);
1782                return;
1783        }
1784
1785        strbuf_addf(&sb,
1786                    (files == 1) ? " %d file changed" : " %d files changed",
1787                    files);
1788
1789        /*
1790         * For binary diff, the caller may want to print "x files
1791         * changed" with insertions == 0 && deletions == 0.
1792         *
1793         * Not omitting "0 insertions(+), 0 deletions(-)" in this case
1794         * is probably less confusing (i.e skip over "2 files changed
1795         * but nothing about added/removed lines? Is this a bug in Git?").
1796         */
1797        if (insertions || deletions == 0) {
1798                strbuf_addf(&sb,
1799                            (insertions == 1) ? ", %d insertion(+)" : ", %d insertions(+)",
1800                            insertions);
1801        }
1802
1803        if (deletions || insertions == 0) {
1804                strbuf_addf(&sb,
1805                            (deletions == 1) ? ", %d deletion(-)" : ", %d deletions(-)",
1806                            deletions);
1807        }
1808        strbuf_addch(&sb, '\n');
1809        emit_diff_symbol(options, DIFF_SYMBOL_STATS_SUMMARY_INSERTS_DELETES,
1810                         sb.buf, sb.len, 0);
1811        strbuf_release(&sb);
1812}
1813
1814void print_stat_summary(FILE *fp, int files,
1815                        int insertions, int deletions)
1816{
1817        struct diff_options o;
1818        memset(&o, 0, sizeof(o));
1819        o.file = fp;
1820
1821        print_stat_summary_inserts_deletes(&o, files, insertions, deletions);
1822}
1823
1824static void show_stats(struct diffstat_t *data, struct diff_options *options)
1825{
1826        int i, len, add, del, adds = 0, dels = 0;
1827        uintmax_t max_change = 0, max_len = 0;
1828        int total_files = data->nr, count;
1829        int width, name_width, graph_width, number_width = 0, bin_width = 0;
1830        const char *reset, *add_c, *del_c;
1831        int extra_shown = 0;
1832        const char *line_prefix = diff_line_prefix(options);
1833        struct strbuf out = STRBUF_INIT;
1834
1835        if (data->nr == 0)
1836                return;
1837
1838        count = options->stat_count ? options->stat_count : data->nr;
1839
1840        reset = diff_get_color_opt(options, DIFF_RESET);
1841        add_c = diff_get_color_opt(options, DIFF_FILE_NEW);
1842        del_c = diff_get_color_opt(options, DIFF_FILE_OLD);
1843
1844        /*
1845         * Find the longest filename and max number of changes
1846         */
1847        for (i = 0; (i < count) && (i < data->nr); i++) {
1848                struct diffstat_file *file = data->files[i];
1849                uintmax_t change = file->added + file->deleted;
1850
1851                if (!file->is_interesting && (change == 0)) {
1852                        count++; /* not shown == room for one more */
1853                        continue;
1854                }
1855                fill_print_name(file);
1856                len = strlen(file->print_name);
1857                if (max_len < len)
1858                        max_len = len;
1859
1860                if (file->is_unmerged) {
1861                        /* "Unmerged" is 8 characters */
1862                        bin_width = bin_width < 8 ? 8 : bin_width;
1863                        continue;
1864                }
1865                if (file->is_binary) {
1866                        /* "Bin XXX -> YYY bytes" */
1867                        int w = 14 + decimal_width(file->added)
1868                                + decimal_width(file->deleted);
1869                        bin_width = bin_width < w ? w : bin_width;
1870                        /* Display change counts aligned with "Bin" */
1871                        number_width = 3;
1872                        continue;
1873                }
1874
1875                if (max_change < change)
1876                        max_change = change;
1877        }
1878        count = i; /* where we can stop scanning in data->files[] */
1879
1880        /*
1881         * We have width = stat_width or term_columns() columns total.
1882         * We want a maximum of min(max_len, stat_name_width) for the name part.
1883         * We want a maximum of min(max_change, stat_graph_width) for the +- part.
1884         * We also need 1 for " " and 4 + decimal_width(max_change)
1885         * for " | NNNN " and one the empty column at the end, altogether
1886         * 6 + decimal_width(max_change).
1887         *
1888         * If there's not enough space, we will use the smaller of
1889         * stat_name_width (if set) and 5/8*width for the filename,
1890         * and the rest for constant elements + graph part, but no more
1891         * than stat_graph_width for the graph part.
1892         * (5/8 gives 50 for filename and 30 for the constant parts + graph
1893         * for the standard terminal size).
1894         *
1895         * In other words: stat_width limits the maximum width, and
1896         * stat_name_width fixes the maximum width of the filename,
1897         * and is also used to divide available columns if there
1898         * aren't enough.
1899         *
1900         * Binary files are displayed with "Bin XXX -> YYY bytes"
1901         * instead of the change count and graph. This part is treated
1902         * similarly to the graph part, except that it is not
1903         * "scaled". If total width is too small to accommodate the
1904         * guaranteed minimum width of the filename part and the
1905         * separators and this message, this message will "overflow"
1906         * making the line longer than the maximum width.
1907         */
1908
1909        if (options->stat_width == -1)
1910                width = term_columns() - strlen(line_prefix);
1911        else
1912                width = options->stat_width ? options->stat_width : 80;
1913        number_width = decimal_width(max_change) > number_width ?
1914                decimal_width(max_change) : number_width;
1915
1916        if (options->stat_graph_width == -1)
1917                options->stat_graph_width = diff_stat_graph_width;
1918
1919        /*
1920         * Guarantee 3/8*16==6 for the graph part
1921         * and 5/8*16==10 for the filename part
1922         */
1923        if (width < 16 + 6 + number_width)
1924                width = 16 + 6 + number_width;
1925
1926        /*
1927         * First assign sizes that are wanted, ignoring available width.
1928         * strlen("Bin XXX -> YYY bytes") == bin_width, and the part
1929         * starting from "XXX" should fit in graph_width.
1930         */
1931        graph_width = max_change + 4 > bin_width ? max_change : bin_width - 4;
1932        if (options->stat_graph_width &&
1933            options->stat_graph_width < graph_width)
1934                graph_width = options->stat_graph_width;
1935
1936        name_width = (options->stat_name_width > 0 &&
1937                      options->stat_name_width < max_len) ?
1938                options->stat_name_width : max_len;
1939
1940        /*
1941         * Adjust adjustable widths not to exceed maximum width
1942         */
1943        if (name_width + number_width + 6 + graph_width > width) {
1944                if (graph_width > width * 3/8 - number_width - 6) {
1945                        graph_width = width * 3/8 - number_width - 6;
1946                        if (graph_width < 6)
1947                                graph_width = 6;
1948                }
1949
1950                if (options->stat_graph_width &&
1951                    graph_width > options->stat_graph_width)
1952                        graph_width = options->stat_graph_width;
1953                if (name_width > width - number_width - 6 - graph_width)
1954                        name_width = width - number_width - 6 - graph_width;
1955                else
1956                        graph_width = width - number_width - 6 - name_width;
1957        }
1958
1959        /*
1960         * From here name_width is the width of the name area,
1961         * and graph_width is the width of the graph area.
1962         * max_change is used to scale graph properly.
1963         */
1964        for (i = 0; i < count; i++) {
1965                const char *prefix = "";
1966                struct diffstat_file *file = data->files[i];
1967                char *name = file->print_name;
1968                uintmax_t added = file->added;
1969                uintmax_t deleted = file->deleted;
1970                int name_len;
1971
1972                if (!file->is_interesting && (added + deleted == 0))
1973                        continue;
1974
1975                /*
1976                 * "scale" the filename
1977                 */
1978                len = name_width;
1979                name_len = strlen(name);
1980                if (name_width < name_len) {
1981                        char *slash;
1982                        prefix = "...";
1983                        len -= 3;
1984                        name += name_len - len;
1985                        slash = strchr(name, '/');
1986                        if (slash)
1987                                name = slash;
1988                }
1989
1990                if (file->is_binary) {
1991                        strbuf_addf(&out, " %s%-*s |", prefix, len, name);
1992                        strbuf_addf(&out, " %*s", number_width, "Bin");
1993                        if (!added && !deleted) {
1994                                strbuf_addch(&out, '\n');
1995                                emit_diff_symbol(options, DIFF_SYMBOL_STATS_LINE,
1996                                                 out.buf, out.len, 0);
1997                                strbuf_reset(&out);
1998                                continue;
1999                        }
2000                        strbuf_addf(&out, " %s%"PRIuMAX"%s",
2001                                del_c, deleted, reset);
2002                        strbuf_addstr(&out, " -> ");
2003                        strbuf_addf(&out, "%s%"PRIuMAX"%s",
2004                                add_c, added, reset);
2005                        strbuf_addstr(&out, " bytes\n");
2006                        emit_diff_symbol(options, DIFF_SYMBOL_STATS_LINE,
2007                                         out.buf, out.len, 0);
2008                        strbuf_reset(&out);
2009                        continue;
2010                }
2011                else if (file->is_unmerged) {
2012                        strbuf_addf(&out, " %s%-*s |", prefix, len, name);
2013                        strbuf_addstr(&out, " Unmerged\n");
2014                        emit_diff_symbol(options, DIFF_SYMBOL_STATS_LINE,
2015                                         out.buf, out.len, 0);
2016                        strbuf_reset(&out);
2017                        continue;
2018                }
2019
2020                /*
2021                 * scale the add/delete
2022                 */
2023                add = added;
2024                del = deleted;
2025
2026                if (graph_width <= max_change) {
2027                        int total = scale_linear(add + del, graph_width, max_change);
2028                        if (total < 2 && add && del)
2029                                /* width >= 2 due to the sanity check */
2030                                total = 2;
2031                        if (add < del) {
2032                                add = scale_linear(add, graph_width, max_change);
2033                                del = total - add;
2034                        } else {
2035                                del = scale_linear(del, graph_width, max_change);
2036                                add = total - del;
2037                        }
2038                }
2039                strbuf_addf(&out, " %s%-*s |", prefix, len, name);
2040                strbuf_addf(&out, " %*"PRIuMAX"%s",
2041                        number_width, added + deleted,
2042                        added + deleted ? " " : "");
2043                show_graph(&out, '+', add, add_c, reset);
2044                show_graph(&out, '-', del, del_c, reset);
2045                strbuf_addch(&out, '\n');
2046                emit_diff_symbol(options, DIFF_SYMBOL_STATS_LINE,
2047                                 out.buf, out.len, 0);
2048                strbuf_reset(&out);
2049        }
2050
2051        for (i = 0; i < data->nr; i++) {
2052                struct diffstat_file *file = data->files[i];
2053                uintmax_t added = file->added;
2054                uintmax_t deleted = file->deleted;
2055
2056                if (file->is_unmerged ||
2057                    (!file->is_interesting && (added + deleted == 0))) {
2058                        total_files--;
2059                        continue;
2060                }
2061
2062                if (!file->is_binary) {
2063                        adds += added;
2064                        dels += deleted;
2065                }
2066                if (i < count)
2067                        continue;
2068                if (!extra_shown)
2069                        emit_diff_symbol(options,
2070                                         DIFF_SYMBOL_STATS_SUMMARY_ABBREV,
2071                                         NULL, 0, 0);
2072                extra_shown = 1;
2073        }
2074
2075        print_stat_summary_inserts_deletes(options, total_files, adds, dels);
2076}
2077
2078static void show_shortstats(struct diffstat_t *data, struct diff_options *options)
2079{
2080        int i, adds = 0, dels = 0, total_files = data->nr;
2081
2082        if (data->nr == 0)
2083                return;
2084
2085        for (i = 0; i < data->nr; i++) {
2086                int added = data->files[i]->added;
2087                int deleted = data->files[i]->deleted;
2088
2089                if (data->files[i]->is_unmerged ||
2090                    (!data->files[i]->is_interesting && (added + deleted == 0))) {
2091                        total_files--;
2092                } else if (!data->files[i]->is_binary) { /* don't count bytes */
2093                        adds += added;
2094                        dels += deleted;
2095                }
2096        }
2097        print_stat_summary_inserts_deletes(options, total_files, adds, dels);
2098}
2099
2100static void show_numstat(struct diffstat_t *data, struct diff_options *options)
2101{
2102        int i;
2103
2104        if (data->nr == 0)
2105                return;
2106
2107        for (i = 0; i < data->nr; i++) {
2108                struct diffstat_file *file = data->files[i];
2109
2110                fprintf(options->file, "%s", diff_line_prefix(options));
2111
2112                if (file->is_binary)
2113                        fprintf(options->file, "-\t-\t");
2114                else
2115                        fprintf(options->file,
2116                                "%"PRIuMAX"\t%"PRIuMAX"\t",
2117                                file->added, file->deleted);
2118                if (options->line_termination) {
2119                        fill_print_name(file);
2120                        if (!file->is_renamed)
2121                                write_name_quoted(file->name, options->file,
2122                                                  options->line_termination);
2123                        else {
2124                                fputs(file->print_name, options->file);
2125                                putc(options->line_termination, options->file);
2126                        }
2127                } else {
2128                        if (file->is_renamed) {
2129                                putc('\0', options->file);
2130                                write_name_quoted(file->from_name, options->file, '\0');
2131                        }
2132                        write_name_quoted(file->name, options->file, '\0');
2133                }
2134        }
2135}
2136
2137struct dirstat_file {
2138        const char *name;
2139        unsigned long changed;
2140};
2141
2142struct dirstat_dir {
2143        struct dirstat_file *files;
2144        int alloc, nr, permille, cumulative;
2145};
2146
2147static long gather_dirstat(struct diff_options *opt, struct dirstat_dir *dir,
2148                unsigned long changed, const char *base, int baselen)
2149{
2150        unsigned long this_dir = 0;
2151        unsigned int sources = 0;
2152        const char *line_prefix = diff_line_prefix(opt);
2153
2154        while (dir->nr) {
2155                struct dirstat_file *f = dir->files;
2156                int namelen = strlen(f->name);
2157                unsigned long this;
2158                char *slash;
2159
2160                if (namelen < baselen)
2161                        break;
2162                if (memcmp(f->name, base, baselen))
2163                        break;
2164                slash = strchr(f->name + baselen, '/');
2165                if (slash) {
2166                        int newbaselen = slash + 1 - f->name;
2167                        this = gather_dirstat(opt, dir, changed, f->name, newbaselen);
2168                        sources++;
2169                } else {
2170                        this = f->changed;
2171                        dir->files++;
2172                        dir->nr--;
2173                        sources += 2;
2174                }
2175                this_dir += this;
2176        }
2177
2178        /*
2179         * We don't report dirstat's for
2180         *  - the top level
2181         *  - or cases where everything came from a single directory
2182         *    under this directory (sources == 1).
2183         */
2184        if (baselen && sources != 1) {
2185                if (this_dir) {
2186                        int permille = this_dir * 1000 / changed;
2187                        if (permille >= dir->permille) {
2188                                fprintf(opt->file, "%s%4d.%01d%% %.*s\n", line_prefix,
2189                                        permille / 10, permille % 10, baselen, base);
2190                                if (!dir->cumulative)
2191                                        return 0;
2192                        }
2193                }
2194        }
2195        return this_dir;
2196}
2197
2198static int dirstat_compare(const void *_a, const void *_b)
2199{
2200        const struct dirstat_file *a = _a;
2201        const struct dirstat_file *b = _b;
2202        return strcmp(a->name, b->name);
2203}
2204
2205static void show_dirstat(struct diff_options *options)
2206{
2207        int i;
2208        unsigned long changed;
2209        struct dirstat_dir dir;
2210        struct diff_queue_struct *q = &diff_queued_diff;
2211
2212        dir.files = NULL;
2213        dir.alloc = 0;
2214        dir.nr = 0;
2215        dir.permille = options->dirstat_permille;
2216        dir.cumulative = DIFF_OPT_TST(options, DIRSTAT_CUMULATIVE);
2217
2218        changed = 0;
2219        for (i = 0; i < q->nr; i++) {
2220                struct diff_filepair *p = q->queue[i];
2221                const char *name;
2222                unsigned long copied, added, damage;
2223                int content_changed;
2224
2225                name = p->two->path ? p->two->path : p->one->path;
2226
2227                if (p->one->oid_valid && p->two->oid_valid)
2228                        content_changed = oidcmp(&p->one->oid, &p->two->oid);
2229                else
2230                        content_changed = 1;
2231
2232                if (!content_changed) {
2233                        /*
2234                         * The SHA1 has not changed, so pre-/post-content is
2235                         * identical. We can therefore skip looking at the
2236                         * file contents altogether.
2237                         */
2238                        damage = 0;
2239                        goto found_damage;
2240                }
2241
2242                if (DIFF_OPT_TST(options, DIRSTAT_BY_FILE)) {
2243                        /*
2244                         * In --dirstat-by-file mode, we don't really need to
2245                         * look at the actual file contents at all.
2246                         * The fact that the SHA1 changed is enough for us to
2247                         * add this file to the list of results
2248                         * (with each file contributing equal damage).
2249                         */
2250                        damage = 1;
2251                        goto found_damage;
2252                }
2253
2254                if (DIFF_FILE_VALID(p->one) && DIFF_FILE_VALID(p->two)) {
2255                        diff_populate_filespec(p->one, 0);
2256                        diff_populate_filespec(p->two, 0);
2257                        diffcore_count_changes(p->one, p->two, NULL, NULL,
2258                                               &copied, &added);
2259                        diff_free_filespec_data(p->one);
2260                        diff_free_filespec_data(p->two);
2261                } else if (DIFF_FILE_VALID(p->one)) {
2262                        diff_populate_filespec(p->one, CHECK_SIZE_ONLY);
2263                        copied = added = 0;
2264                        diff_free_filespec_data(p->one);
2265                } else if (DIFF_FILE_VALID(p->two)) {
2266                        diff_populate_filespec(p->two, CHECK_SIZE_ONLY);
2267                        copied = 0;
2268                        added = p->two->size;
2269                        diff_free_filespec_data(p->two);
2270                } else
2271                        continue;
2272
2273                /*
2274                 * Original minus copied is the removed material,
2275                 * added is the new material.  They are both damages
2276                 * made to the preimage.
2277                 * If the resulting damage is zero, we know that
2278                 * diffcore_count_changes() considers the two entries to
2279                 * be identical, but since content_changed is true, we
2280                 * know that there must have been _some_ kind of change,
2281                 * so we force all entries to have damage > 0.
2282                 */
2283                damage = (p->one->size - copied) + added;
2284                if (!damage)
2285                        damage = 1;
2286
2287found_damage:
2288                ALLOC_GROW(dir.files, dir.nr + 1, dir.alloc);
2289                dir.files[dir.nr].name = name;
2290                dir.files[dir.nr].changed = damage;
2291                changed += damage;
2292                dir.nr++;
2293        }
2294
2295        /* This can happen even with many files, if everything was renames */
2296        if (!changed)
2297                return;
2298
2299        /* Show all directories with more than x% of the changes */
2300        QSORT(dir.files, dir.nr, dirstat_compare);
2301        gather_dirstat(options, &dir, changed, "", 0);
2302}
2303
2304static void show_dirstat_by_line(struct diffstat_t *data, struct diff_options *options)
2305{
2306        int i;
2307        unsigned long changed;
2308        struct dirstat_dir dir;
2309
2310        if (data->nr == 0)
2311                return;
2312
2313        dir.files = NULL;
2314        dir.alloc = 0;
2315        dir.nr = 0;
2316        dir.permille = options->dirstat_permille;
2317        dir.cumulative = DIFF_OPT_TST(options, DIRSTAT_CUMULATIVE);
2318
2319        changed = 0;
2320        for (i = 0; i < data->nr; i++) {
2321                struct diffstat_file *file = data->files[i];
2322                unsigned long damage = file->added + file->deleted;
2323                if (file->is_binary)
2324                        /*
2325                         * binary files counts bytes, not lines. Must find some
2326                         * way to normalize binary bytes vs. textual lines.
2327                         * The following heuristic assumes that there are 64
2328                         * bytes per "line".
2329                         * This is stupid and ugly, but very cheap...
2330                         */
2331                        damage = (damage + 63) / 64;
2332                ALLOC_GROW(dir.files, dir.nr + 1, dir.alloc);
2333                dir.files[dir.nr].name = file->name;
2334                dir.files[dir.nr].changed = damage;
2335                changed += damage;
2336                dir.nr++;
2337        }
2338
2339        /* This can happen even with many files, if everything was renames */
2340        if (!changed)
2341                return;
2342
2343        /* Show all directories with more than x% of the changes */
2344        QSORT(dir.files, dir.nr, dirstat_compare);
2345        gather_dirstat(options, &dir, changed, "", 0);
2346}
2347
2348static void free_diffstat_info(struct diffstat_t *diffstat)
2349{
2350        int i;
2351        for (i = 0; i < diffstat->nr; i++) {
2352                struct diffstat_file *f = diffstat->files[i];
2353                if (f->name != f->print_name)
2354                        free(f->print_name);
2355                free(f->name);
2356                free(f->from_name);
2357                free(f);
2358        }
2359        free(diffstat->files);
2360}
2361
2362struct checkdiff_t {
2363        const char *filename;
2364        int lineno;
2365        int conflict_marker_size;
2366        struct diff_options *o;
2367        unsigned ws_rule;
2368        unsigned status;
2369};
2370
2371static int is_conflict_marker(const char *line, int marker_size, unsigned long len)
2372{
2373        char firstchar;
2374        int cnt;
2375
2376        if (len < marker_size + 1)
2377                return 0;
2378        firstchar = line[0];
2379        switch (firstchar) {
2380        case '=': case '>': case '<': case '|':
2381                break;
2382        default:
2383                return 0;
2384        }
2385        for (cnt = 1; cnt < marker_size; cnt++)
2386                if (line[cnt] != firstchar)
2387                        return 0;
2388        /* line[1] thru line[marker_size-1] are same as firstchar */
2389        if (len < marker_size + 1 || !isspace(line[marker_size]))
2390                return 0;
2391        return 1;
2392}
2393
2394static void checkdiff_consume(void *priv, char *line, unsigned long len)
2395{
2396        struct checkdiff_t *data = priv;
2397        int marker_size = data->conflict_marker_size;
2398        const char *ws = diff_get_color(data->o->use_color, DIFF_WHITESPACE);
2399        const char *reset = diff_get_color(data->o->use_color, DIFF_RESET);
2400        const char *set = diff_get_color(data->o->use_color, DIFF_FILE_NEW);
2401        char *err;
2402        const char *line_prefix;
2403
2404        assert(data->o);
2405        line_prefix = diff_line_prefix(data->o);
2406
2407        if (line[0] == '+') {
2408                unsigned bad;
2409                data->lineno++;
2410                if (is_conflict_marker(line + 1, marker_size, len - 1)) {
2411                        data->status |= 1;
2412                        fprintf(data->o->file,
2413                                "%s%s:%d: leftover conflict marker\n",
2414                                line_prefix, data->filename, data->lineno);
2415                }
2416                bad = ws_check(line + 1, len - 1, data->ws_rule);
2417                if (!bad)
2418                        return;
2419                data->status |= bad;
2420                err = whitespace_error_string(bad);
2421                fprintf(data->o->file, "%s%s:%d: %s.\n",
2422                        line_prefix, data->filename, data->lineno, err);
2423                free(err);
2424                emit_line(data->o, set, reset, line, 1);
2425                ws_check_emit(line + 1, len - 1, data->ws_rule,
2426                              data->o->file, set, reset, ws);
2427        } else if (line[0] == ' ') {
2428                data->lineno++;
2429        } else if (line[0] == '@') {
2430                char *plus = strchr(line, '+');
2431                if (plus)
2432                        data->lineno = strtol(plus, NULL, 10) - 1;
2433                else
2434                        die("invalid diff");
2435        }
2436}
2437
2438static unsigned char *deflate_it(char *data,
2439                                 unsigned long size,
2440                                 unsigned long *result_size)
2441{
2442        int bound;
2443        unsigned char *deflated;
2444        git_zstream stream;
2445
2446        git_deflate_init(&stream, zlib_compression_level);
2447        bound = git_deflate_bound(&stream, size);
2448        deflated = xmalloc(bound);
2449        stream.next_out = deflated;
2450        stream.avail_out = bound;
2451
2452        stream.next_in = (unsigned char *)data;
2453        stream.avail_in = size;
2454        while (git_deflate(&stream, Z_FINISH) == Z_OK)
2455                ; /* nothing */
2456        git_deflate_end(&stream);
2457        *result_size = stream.total_out;
2458        return deflated;
2459}
2460
2461static void emit_binary_diff_body(struct diff_options *o,
2462                                  mmfile_t *one, mmfile_t *two)
2463{
2464        void *cp;
2465        void *delta;
2466        void *deflated;
2467        void *data;
2468        unsigned long orig_size;
2469        unsigned long delta_size;
2470        unsigned long deflate_size;
2471        unsigned long data_size;
2472
2473        /* We could do deflated delta, or we could do just deflated two,
2474         * whichever is smaller.
2475         */
2476        delta = NULL;
2477        deflated = deflate_it(two->ptr, two->size, &deflate_size);
2478        if (one->size && two->size) {
2479                delta = diff_delta(one->ptr, one->size,
2480                                   two->ptr, two->size,
2481                                   &delta_size, deflate_size);
2482                if (delta) {
2483                        void *to_free = delta;
2484                        orig_size = delta_size;
2485                        delta = deflate_it(delta, delta_size, &delta_size);
2486                        free(to_free);
2487                }
2488        }
2489
2490        if (delta && delta_size < deflate_size) {
2491                char *s = xstrfmt("%lu", orig_size);
2492                emit_diff_symbol(o, DIFF_SYMBOL_BINARY_DIFF_HEADER_DELTA,
2493                                 s, strlen(s), 0);
2494                free(s);
2495                free(deflated);
2496                data = delta;
2497                data_size = delta_size;
2498        } else {
2499                char *s = xstrfmt("%lu", two->size);
2500                emit_diff_symbol(o, DIFF_SYMBOL_BINARY_DIFF_HEADER_LITERAL,
2501                                 s, strlen(s), 0);
2502                free(s);
2503                free(delta);
2504                data = deflated;
2505                data_size = deflate_size;
2506        }
2507
2508        /* emit data encoded in base85 */
2509        cp = data;
2510        while (data_size) {
2511                int len;
2512                int bytes = (52 < data_size) ? 52 : data_size;
2513                char line[71];
2514                data_size -= bytes;
2515                if (bytes <= 26)
2516                        line[0] = bytes + 'A' - 1;
2517                else
2518                        line[0] = bytes - 26 + 'a' - 1;
2519                encode_85(line + 1, cp, bytes);
2520                cp = (char *) cp + bytes;
2521
2522                len = strlen(line);
2523                line[len++] = '\n';
2524                line[len] = '\0';
2525
2526                emit_diff_symbol(o, DIFF_SYMBOL_BINARY_DIFF_BODY,
2527                                 line, len, 0);
2528        }
2529        emit_diff_symbol(o, DIFF_SYMBOL_BINARY_DIFF_FOOTER, NULL, 0, 0);
2530        free(data);
2531}
2532
2533static void emit_binary_diff(struct diff_options *o,
2534                             mmfile_t *one, mmfile_t *two)
2535{
2536        emit_diff_symbol(o, DIFF_SYMBOL_BINARY_DIFF_HEADER, NULL, 0, 0);
2537        emit_binary_diff_body(o, one, two);
2538        emit_binary_diff_body(o, two, one);
2539}
2540
2541int diff_filespec_is_binary(struct diff_filespec *one)
2542{
2543        if (one->is_binary == -1) {
2544                diff_filespec_load_driver(one);
2545                if (one->driver->binary != -1)
2546                        one->is_binary = one->driver->binary;
2547                else {
2548                        if (!one->data && DIFF_FILE_VALID(one))
2549                                diff_populate_filespec(one, CHECK_BINARY);
2550                        if (one->is_binary == -1 && one->data)
2551                                one->is_binary = buffer_is_binary(one->data,
2552                                                one->size);
2553                        if (one->is_binary == -1)
2554                                one->is_binary = 0;
2555                }
2556        }
2557        return one->is_binary;
2558}
2559
2560static const struct userdiff_funcname *diff_funcname_pattern(struct diff_filespec *one)
2561{
2562        diff_filespec_load_driver(one);
2563        return one->driver->funcname.pattern ? &one->driver->funcname : NULL;
2564}
2565
2566void diff_set_mnemonic_prefix(struct diff_options *options, const char *a, const char *b)
2567{
2568        if (!options->a_prefix)
2569                options->a_prefix = a;
2570        if (!options->b_prefix)
2571                options->b_prefix = b;
2572}
2573
2574struct userdiff_driver *get_textconv(struct diff_filespec *one)
2575{
2576        if (!DIFF_FILE_VALID(one))
2577                return NULL;
2578
2579        diff_filespec_load_driver(one);
2580        return userdiff_get_textconv(one->driver);
2581}
2582
2583static void builtin_diff(const char *name_a,
2584                         const char *name_b,
2585                         struct diff_filespec *one,
2586                         struct diff_filespec *two,
2587                         const char *xfrm_msg,
2588                         int must_show_header,
2589                         struct diff_options *o,
2590                         int complete_rewrite)
2591{
2592        mmfile_t mf1, mf2;
2593        const char *lbl[2];
2594        char *a_one, *b_two;
2595        const char *meta = diff_get_color_opt(o, DIFF_METAINFO);
2596        const char *reset = diff_get_color_opt(o, DIFF_RESET);
2597        const char *a_prefix, *b_prefix;
2598        struct userdiff_driver *textconv_one = NULL;
2599        struct userdiff_driver *textconv_two = NULL;
2600        struct strbuf header = STRBUF_INIT;
2601        const char *line_prefix = diff_line_prefix(o);
2602
2603        diff_set_mnemonic_prefix(o, "a/", "b/");
2604        if (DIFF_OPT_TST(o, REVERSE_DIFF)) {
2605                a_prefix = o->b_prefix;
2606                b_prefix = o->a_prefix;
2607        } else {
2608                a_prefix = o->a_prefix;
2609                b_prefix = o->b_prefix;
2610        }
2611
2612        if (o->submodule_format == DIFF_SUBMODULE_LOG &&
2613            (!one->mode || S_ISGITLINK(one->mode)) &&
2614            (!two->mode || S_ISGITLINK(two->mode))) {
2615                show_submodule_summary(o, one->path ? one->path : two->path,
2616                                &one->oid, &two->oid,
2617                                two->dirty_submodule);
2618                return;
2619        } else if (o->submodule_format == DIFF_SUBMODULE_INLINE_DIFF &&
2620                   (!one->mode || S_ISGITLINK(one->mode)) &&
2621                   (!two->mode || S_ISGITLINK(two->mode))) {
2622                show_submodule_inline_diff(o, one->path ? one->path : two->path,
2623                                &one->oid, &two->oid,
2624                                two->dirty_submodule);
2625                return;
2626        }
2627
2628        if (DIFF_OPT_TST(o, ALLOW_TEXTCONV)) {
2629                textconv_one = get_textconv(one);
2630                textconv_two = get_textconv(two);
2631        }
2632
2633        /* Never use a non-valid filename anywhere if at all possible */
2634        name_a = DIFF_FILE_VALID(one) ? name_a : name_b;
2635        name_b = DIFF_FILE_VALID(two) ? name_b : name_a;
2636
2637        a_one = quote_two(a_prefix, name_a + (*name_a == '/'));
2638        b_two = quote_two(b_prefix, name_b + (*name_b == '/'));
2639        lbl[0] = DIFF_FILE_VALID(one) ? a_one : "/dev/null";
2640        lbl[1] = DIFF_FILE_VALID(two) ? b_two : "/dev/null";
2641        strbuf_addf(&header, "%s%sdiff --git %s %s%s\n", line_prefix, meta, a_one, b_two, reset);
2642        if (lbl[0][0] == '/') {
2643                /* /dev/null */
2644                strbuf_addf(&header, "%s%snew file mode %06o%s\n", line_prefix, meta, two->mode, reset);
2645                if (xfrm_msg)
2646                        strbuf_addstr(&header, xfrm_msg);
2647                must_show_header = 1;
2648        }
2649        else if (lbl[1][0] == '/') {
2650                strbuf_addf(&header, "%s%sdeleted file mode %06o%s\n", line_prefix, meta, one->mode, reset);
2651                if (xfrm_msg)
2652                        strbuf_addstr(&header, xfrm_msg);
2653                must_show_header = 1;
2654        }
2655        else {
2656                if (one->mode != two->mode) {
2657                        strbuf_addf(&header, "%s%sold mode %06o%s\n", line_prefix, meta, one->mode, reset);
2658                        strbuf_addf(&header, "%s%snew mode %06o%s\n", line_prefix, meta, two->mode, reset);
2659                        must_show_header = 1;
2660                }
2661                if (xfrm_msg)
2662                        strbuf_addstr(&header, xfrm_msg);
2663
2664                /*
2665                 * we do not run diff between different kind
2666                 * of objects.
2667                 */
2668                if ((one->mode ^ two->mode) & S_IFMT)
2669                        goto free_ab_and_return;
2670                if (complete_rewrite &&
2671                    (textconv_one || !diff_filespec_is_binary(one)) &&
2672                    (textconv_two || !diff_filespec_is_binary(two))) {
2673                        emit_diff_symbol(o, DIFF_SYMBOL_HEADER,
2674                                         header.buf, header.len, 0);
2675                        strbuf_reset(&header);
2676                        emit_rewrite_diff(name_a, name_b, one, two,
2677                                                textconv_one, textconv_two, o);
2678                        o->found_changes = 1;
2679                        goto free_ab_and_return;
2680                }
2681        }
2682
2683        if (o->irreversible_delete && lbl[1][0] == '/') {
2684                emit_diff_symbol(o, DIFF_SYMBOL_HEADER, header.buf,
2685                                 header.len, 0);
2686                strbuf_reset(&header);
2687                goto free_ab_and_return;
2688        } else if (!DIFF_OPT_TST(o, TEXT) &&
2689            ( (!textconv_one && diff_filespec_is_binary(one)) ||
2690              (!textconv_two && diff_filespec_is_binary(two)) )) {
2691                struct strbuf sb = STRBUF_INIT;
2692                if (!one->data && !two->data &&
2693                    S_ISREG(one->mode) && S_ISREG(two->mode) &&
2694                    !DIFF_OPT_TST(o, BINARY)) {
2695                        if (!oidcmp(&one->oid, &two->oid)) {
2696                                if (must_show_header)
2697                                        emit_diff_symbol(o, DIFF_SYMBOL_HEADER,
2698                                                         header.buf, header.len,
2699                                                         0);
2700                                goto free_ab_and_return;
2701                        }
2702                        emit_diff_symbol(o, DIFF_SYMBOL_HEADER,
2703                                         header.buf, header.len, 0);
2704                        strbuf_addf(&sb, "%sBinary files %s and %s differ\n",
2705                                    diff_line_prefix(o), lbl[0], lbl[1]);
2706                        emit_diff_symbol(o, DIFF_SYMBOL_BINARY_FILES,
2707                                         sb.buf, sb.len, 0);
2708                        strbuf_release(&sb);
2709                        goto free_ab_and_return;
2710                }
2711                if (fill_mmfile(&mf1, one) < 0 || fill_mmfile(&mf2, two) < 0)
2712                        die("unable to read files to diff");
2713                /* Quite common confusing case */
2714                if (mf1.size == mf2.size &&
2715                    !memcmp(mf1.ptr, mf2.ptr, mf1.size)) {
2716                        if (must_show_header)
2717                                emit_diff_symbol(o, DIFF_SYMBOL_HEADER,
2718                                                 header.buf, header.len, 0);
2719                        goto free_ab_and_return;
2720                }
2721                emit_diff_symbol(o, DIFF_SYMBOL_HEADER, header.buf, header.len, 0);
2722                strbuf_reset(&header);
2723                if (DIFF_OPT_TST(o, BINARY))
2724                        emit_binary_diff(o, &mf1, &mf2);
2725                else {
2726                        strbuf_addf(&sb, "%sBinary files %s and %s differ\n",
2727                                    diff_line_prefix(o), lbl[0], lbl[1]);
2728                        emit_diff_symbol(o, DIFF_SYMBOL_BINARY_FILES,
2729                                         sb.buf, sb.len, 0);
2730                        strbuf_release(&sb);
2731                }
2732                o->found_changes = 1;
2733        } else {
2734                /* Crazy xdl interfaces.. */
2735                const char *diffopts = getenv("GIT_DIFF_OPTS");
2736                const char *v;
2737                xpparam_t xpp;
2738                xdemitconf_t xecfg;
2739                struct emit_callback ecbdata;
2740                const struct userdiff_funcname *pe;
2741
2742                if (must_show_header) {
2743                        emit_diff_symbol(o, DIFF_SYMBOL_HEADER,
2744                                         header.buf, header.len, 0);
2745                        strbuf_reset(&header);
2746                }
2747
2748                mf1.size = fill_textconv(textconv_one, one, &mf1.ptr);
2749                mf2.size = fill_textconv(textconv_two, two, &mf2.ptr);
2750
2751                pe = diff_funcname_pattern(one);
2752                if (!pe)
2753                        pe = diff_funcname_pattern(two);
2754
2755                memset(&xpp, 0, sizeof(xpp));
2756                memset(&xecfg, 0, sizeof(xecfg));
2757                memset(&ecbdata, 0, sizeof(ecbdata));
2758                ecbdata.label_path = lbl;
2759                ecbdata.color_diff = want_color(o->use_color);
2760                ecbdata.ws_rule = whitespace_rule(name_b);
2761                if (ecbdata.ws_rule & WS_BLANK_AT_EOF)
2762                        check_blank_at_eof(&mf1, &mf2, &ecbdata);
2763                ecbdata.opt = o;
2764                ecbdata.header = header.len ? &header : NULL;
2765                xpp.flags = o->xdl_opts;
2766                xecfg.ctxlen = o->context;
2767                xecfg.interhunkctxlen = o->interhunkcontext;
2768                xecfg.flags = XDL_EMIT_FUNCNAMES;
2769                if (DIFF_OPT_TST(o, FUNCCONTEXT))
2770                        xecfg.flags |= XDL_EMIT_FUNCCONTEXT;
2771                if (pe)
2772                        xdiff_set_find_func(&xecfg, pe->pattern, pe->cflags);
2773                if (!diffopts)
2774                        ;
2775                else if (skip_prefix(diffopts, "--unified=", &v))
2776                        xecfg.ctxlen = strtoul(v, NULL, 10);
2777                else if (skip_prefix(diffopts, "-u", &v))
2778                        xecfg.ctxlen = strtoul(v, NULL, 10);
2779                if (o->word_diff)
2780                        init_diff_words_data(&ecbdata, o, one, two);
2781                if (xdi_diff_outf(&mf1, &mf2, fn_out_consume, &ecbdata,
2782                                  &xpp, &xecfg))
2783                        die("unable to generate diff for %s", one->path);
2784                if (o->word_diff)
2785                        free_diff_words_data(&ecbdata);
2786                if (textconv_one)
2787                        free(mf1.ptr);
2788                if (textconv_two)
2789                        free(mf2.ptr);
2790                xdiff_clear_find_func(&xecfg);
2791        }
2792
2793 free_ab_and_return:
2794        strbuf_release(&header);
2795        diff_free_filespec_data(one);
2796        diff_free_filespec_data(two);
2797        free(a_one);
2798        free(b_two);
2799        return;
2800}
2801
2802static void builtin_diffstat(const char *name_a, const char *name_b,
2803                             struct diff_filespec *one,
2804                             struct diff_filespec *two,
2805                             struct diffstat_t *diffstat,
2806                             struct diff_options *o,
2807                             struct diff_filepair *p)
2808{
2809        mmfile_t mf1, mf2;
2810        struct diffstat_file *data;
2811        int same_contents;
2812        int complete_rewrite = 0;
2813
2814        if (!DIFF_PAIR_UNMERGED(p)) {
2815                if (p->status == DIFF_STATUS_MODIFIED && p->score)
2816                        complete_rewrite = 1;
2817        }
2818
2819        data = diffstat_add(diffstat, name_a, name_b);
2820        data->is_interesting = p->status != DIFF_STATUS_UNKNOWN;
2821
2822        if (!one || !two) {
2823                data->is_unmerged = 1;
2824                return;
2825        }
2826
2827        same_contents = !oidcmp(&one->oid, &two->oid);
2828
2829        if (diff_filespec_is_binary(one) || diff_filespec_is_binary(two)) {
2830                data->is_binary = 1;
2831                if (same_contents) {
2832                        data->added = 0;
2833                        data->deleted = 0;
2834                } else {
2835                        data->added = diff_filespec_size(two);
2836                        data->deleted = diff_filespec_size(one);
2837                }
2838        }
2839
2840        else if (complete_rewrite) {
2841                diff_populate_filespec(one, 0);
2842                diff_populate_filespec(two, 0);
2843                data->deleted = count_lines(one->data, one->size);
2844                data->added = count_lines(two->data, two->size);
2845        }
2846
2847        else if (!same_contents) {
2848                /* Crazy xdl interfaces.. */
2849                xpparam_t xpp;
2850                xdemitconf_t xecfg;
2851
2852                if (fill_mmfile(&mf1, one) < 0 || fill_mmfile(&mf2, two) < 0)
2853                        die("unable to read files to diff");
2854
2855                memset(&xpp, 0, sizeof(xpp));
2856                memset(&xecfg, 0, sizeof(xecfg));
2857                xpp.flags = o->xdl_opts;
2858                xecfg.ctxlen = o->context;
2859                xecfg.interhunkctxlen = o->interhunkcontext;
2860                if (xdi_diff_outf(&mf1, &mf2, diffstat_consume, diffstat,
2861                                  &xpp, &xecfg))
2862                        die("unable to generate diffstat for %s", one->path);
2863        }
2864
2865        diff_free_filespec_data(one);
2866        diff_free_filespec_data(two);
2867}
2868
2869static void builtin_checkdiff(const char *name_a, const char *name_b,
2870                              const char *attr_path,
2871                              struct diff_filespec *one,
2872                              struct diff_filespec *two,
2873                              struct diff_options *o)
2874{
2875        mmfile_t mf1, mf2;
2876        struct checkdiff_t data;
2877
2878        if (!two)
2879                return;
2880
2881        memset(&data, 0, sizeof(data));
2882        data.filename = name_b ? name_b : name_a;
2883        data.lineno = 0;
2884        data.o = o;
2885        data.ws_rule = whitespace_rule(attr_path);
2886        data.conflict_marker_size = ll_merge_marker_size(attr_path);
2887
2888        if (fill_mmfile(&mf1, one) < 0 || fill_mmfile(&mf2, two) < 0)
2889                die("unable to read files to diff");
2890
2891        /*
2892         * All the other codepaths check both sides, but not checking
2893         * the "old" side here is deliberate.  We are checking the newly
2894         * introduced changes, and as long as the "new" side is text, we
2895         * can and should check what it introduces.
2896         */
2897        if (diff_filespec_is_binary(two))
2898                goto free_and_return;
2899        else {
2900                /* Crazy xdl interfaces.. */
2901                xpparam_t xpp;
2902                xdemitconf_t xecfg;
2903
2904                memset(&xpp, 0, sizeof(xpp));
2905                memset(&xecfg, 0, sizeof(xecfg));
2906                xecfg.ctxlen = 1; /* at least one context line */
2907                xpp.flags = 0;
2908                if (xdi_diff_outf(&mf1, &mf2, checkdiff_consume, &data,
2909                                  &xpp, &xecfg))
2910                        die("unable to generate checkdiff for %s", one->path);
2911
2912                if (data.ws_rule & WS_BLANK_AT_EOF) {
2913                        struct emit_callback ecbdata;
2914                        int blank_at_eof;
2915
2916                        ecbdata.ws_rule = data.ws_rule;
2917                        check_blank_at_eof(&mf1, &mf2, &ecbdata);
2918                        blank_at_eof = ecbdata.blank_at_eof_in_postimage;
2919
2920                        if (blank_at_eof) {
2921                                static char *err;
2922                                if (!err)
2923                                        err = whitespace_error_string(WS_BLANK_AT_EOF);
2924                                fprintf(o->file, "%s:%d: %s.\n",
2925                                        data.filename, blank_at_eof, err);
2926                                data.status = 1; /* report errors */
2927                        }
2928                }
2929        }
2930 free_and_return:
2931        diff_free_filespec_data(one);
2932        diff_free_filespec_data(two);
2933        if (data.status)
2934                DIFF_OPT_SET(o, CHECK_FAILED);
2935}
2936
2937struct diff_filespec *alloc_filespec(const char *path)
2938{
2939        struct diff_filespec *spec;
2940
2941        FLEXPTR_ALLOC_STR(spec, path, path);
2942        spec->count = 1;
2943        spec->is_binary = -1;
2944        return spec;
2945}
2946
2947void free_filespec(struct diff_filespec *spec)
2948{
2949        if (!--spec->count) {
2950                diff_free_filespec_data(spec);
2951                free(spec);
2952        }
2953}
2954
2955void fill_filespec(struct diff_filespec *spec, const struct object_id *oid,
2956                   int oid_valid, unsigned short mode)
2957{
2958        if (mode) {
2959                spec->mode = canon_mode(mode);
2960                oidcpy(&spec->oid, oid);
2961                spec->oid_valid = oid_valid;
2962        }
2963}
2964
2965/*
2966 * Given a name and sha1 pair, if the index tells us the file in
2967 * the work tree has that object contents, return true, so that
2968 * prepare_temp_file() does not have to inflate and extract.
2969 */
2970static int reuse_worktree_file(const char *name, const struct object_id *oid, int want_file)
2971{
2972        const struct cache_entry *ce;
2973        struct stat st;
2974        int pos, len;
2975
2976        /*
2977         * We do not read the cache ourselves here, because the
2978         * benchmark with my previous version that always reads cache
2979         * shows that it makes things worse for diff-tree comparing
2980         * two linux-2.6 kernel trees in an already checked out work
2981         * tree.  This is because most diff-tree comparisons deal with
2982         * only a small number of files, while reading the cache is
2983         * expensive for a large project, and its cost outweighs the
2984         * savings we get by not inflating the object to a temporary
2985         * file.  Practically, this code only helps when we are used
2986         * by diff-cache --cached, which does read the cache before
2987         * calling us.
2988         */
2989        if (!active_cache)
2990                return 0;
2991
2992        /* We want to avoid the working directory if our caller
2993         * doesn't need the data in a normal file, this system
2994         * is rather slow with its stat/open/mmap/close syscalls,
2995         * and the object is contained in a pack file.  The pack
2996         * is probably already open and will be faster to obtain
2997         * the data through than the working directory.  Loose
2998         * objects however would tend to be slower as they need
2999         * to be individually opened and inflated.
3000         */
3001        if (!FAST_WORKING_DIRECTORY && !want_file && has_sha1_pack(oid->hash))
3002                return 0;
3003
3004        /*
3005         * Similarly, if we'd have to convert the file contents anyway, that
3006         * makes the optimization not worthwhile.
3007         */
3008        if (!want_file && would_convert_to_git(&the_index, name))
3009                return 0;
3010
3011        len = strlen(name);
3012        pos = cache_name_pos(name, len);
3013        if (pos < 0)
3014                return 0;
3015        ce = active_cache[pos];
3016
3017        /*
3018         * This is not the sha1 we are looking for, or
3019         * unreusable because it is not a regular file.
3020         */
3021        if (oidcmp(oid, &ce->oid) || !S_ISREG(ce->ce_mode))
3022                return 0;
3023
3024        /*
3025         * If ce is marked as "assume unchanged", there is no
3026         * guarantee that work tree matches what we are looking for.
3027         */
3028        if ((ce->ce_flags & CE_VALID) || ce_skip_worktree(ce))
3029                return 0;
3030
3031        /*
3032         * If ce matches the file in the work tree, we can reuse it.
3033         */
3034        if (ce_uptodate(ce) ||
3035            (!lstat(name, &st) && !ce_match_stat(ce, &st, 0)))
3036                return 1;
3037
3038        return 0;
3039}
3040
3041static int diff_populate_gitlink(struct diff_filespec *s, int size_only)
3042{
3043        struct strbuf buf = STRBUF_INIT;
3044        char *dirty = "";
3045
3046        /* Are we looking at the work tree? */
3047        if (s->dirty_submodule)
3048                dirty = "-dirty";
3049
3050        strbuf_addf(&buf, "Subproject commit %s%s\n",
3051                    oid_to_hex(&s->oid), dirty);
3052        s->size = buf.len;
3053        if (size_only) {
3054                s->data = NULL;
3055                strbuf_release(&buf);
3056        } else {
3057                s->data = strbuf_detach(&buf, NULL);
3058                s->should_free = 1;
3059        }
3060        return 0;
3061}
3062
3063/*
3064 * While doing rename detection and pickaxe operation, we may need to
3065 * grab the data for the blob (or file) for our own in-core comparison.
3066 * diff_filespec has data and size fields for this purpose.
3067 */
3068int diff_populate_filespec(struct diff_filespec *s, unsigned int flags)
3069{
3070        int size_only = flags & CHECK_SIZE_ONLY;
3071        int err = 0;
3072        /*
3073         * demote FAIL to WARN to allow inspecting the situation
3074         * instead of refusing.
3075         */
3076        enum safe_crlf crlf_warn = (safe_crlf == SAFE_CRLF_FAIL
3077                                    ? SAFE_CRLF_WARN
3078                                    : safe_crlf);
3079
3080        if (!DIFF_FILE_VALID(s))
3081                die("internal error: asking to populate invalid file.");
3082        if (S_ISDIR(s->mode))
3083                return -1;
3084
3085        if (s->data)
3086                return 0;
3087
3088        if (size_only && 0 < s->size)
3089                return 0;
3090
3091        if (S_ISGITLINK(s->mode))
3092                return diff_populate_gitlink(s, size_only);
3093
3094        if (!s->oid_valid ||
3095            reuse_worktree_file(s->path, &s->oid, 0)) {
3096                struct strbuf buf = STRBUF_INIT;
3097                struct stat st;
3098                int fd;
3099
3100                if (lstat(s->path, &st) < 0) {
3101                        if (errno == ENOENT) {
3102                        err_empty:
3103                                err = -1;
3104                        empty:
3105                                s->data = (char *)"";
3106                                s->size = 0;
3107                                return err;
3108                        }
3109                }
3110                s->size = xsize_t(st.st_size);
3111                if (!s->size)
3112                        goto empty;
3113                if (S_ISLNK(st.st_mode)) {
3114                        struct strbuf sb = STRBUF_INIT;
3115
3116                        if (strbuf_readlink(&sb, s->path, s->size))
3117                                goto err_empty;
3118                        s->size = sb.len;
3119                        s->data = strbuf_detach(&sb, NULL);
3120                        s->should_free = 1;
3121                        return 0;
3122                }
3123
3124                /*
3125                 * Even if the caller would be happy with getting
3126                 * only the size, we cannot return early at this
3127                 * point if the path requires us to run the content
3128                 * conversion.
3129                 */
3130                if (size_only && !would_convert_to_git(&the_index, s->path))
3131                        return 0;
3132
3133                /*
3134                 * Note: this check uses xsize_t(st.st_size) that may
3135                 * not be the true size of the blob after it goes
3136                 * through convert_to_git().  This may not strictly be
3137                 * correct, but the whole point of big_file_threshold
3138                 * and is_binary check being that we want to avoid
3139                 * opening the file and inspecting the contents, this
3140                 * is probably fine.
3141                 */
3142                if ((flags & CHECK_BINARY) &&
3143                    s->size > big_file_threshold && s->is_binary == -1) {
3144                        s->is_binary = 1;
3145                        return 0;
3146                }
3147                fd = open(s->path, O_RDONLY);
3148                if (fd < 0)
3149                        goto err_empty;
3150                s->data = xmmap(NULL, s->size, PROT_READ, MAP_PRIVATE, fd, 0);
3151                close(fd);
3152                s->should_munmap = 1;
3153
3154                /*
3155                 * Convert from working tree format to canonical git format
3156                 */
3157                if (convert_to_git(&the_index, s->path, s->data, s->size, &buf, crlf_warn)) {
3158                        size_t size = 0;
3159                        munmap(s->data, s->size);
3160                        s->should_munmap = 0;
3161                        s->data = strbuf_detach(&buf, &size);
3162                        s->size = size;
3163                        s->should_free = 1;
3164                }
3165        }
3166        else {
3167                enum object_type type;
3168                if (size_only || (flags & CHECK_BINARY)) {
3169                        type = sha1_object_info(s->oid.hash, &s->size);
3170                        if (type < 0)
3171                                die("unable to read %s",
3172                                    oid_to_hex(&s->oid));
3173                        if (size_only)
3174                                return 0;
3175                        if (s->size > big_file_threshold && s->is_binary == -1) {
3176                                s->is_binary = 1;
3177                                return 0;
3178                        }
3179                }
3180                s->data = read_sha1_file(s->oid.hash, &type, &s->size);
3181                if (!s->data)
3182                        die("unable to read %s", oid_to_hex(&s->oid));
3183                s->should_free = 1;
3184        }
3185        return 0;
3186}
3187
3188void diff_free_filespec_blob(struct diff_filespec *s)
3189{
3190        if (s->should_free)
3191                free(s->data);
3192        else if (s->should_munmap)
3193                munmap(s->data, s->size);
3194
3195        if (s->should_free || s->should_munmap) {
3196                s->should_free = s->should_munmap = 0;
3197                s->data = NULL;
3198        }
3199}
3200
3201void diff_free_filespec_data(struct diff_filespec *s)
3202{
3203        diff_free_filespec_blob(s);
3204        FREE_AND_NULL(s->cnt_data);
3205}
3206
3207static void prep_temp_blob(const char *path, struct diff_tempfile *temp,
3208                           void *blob,
3209                           unsigned long size,
3210                           const struct object_id *oid,
3211                           int mode)
3212{
3213        int fd;
3214        struct strbuf buf = STRBUF_INIT;
3215        struct strbuf template = STRBUF_INIT;
3216        char *path_dup = xstrdup(path);
3217        const char *base = basename(path_dup);
3218
3219        /* Generate "XXXXXX_basename.ext" */
3220        strbuf_addstr(&template, "XXXXXX_");
3221        strbuf_addstr(&template, base);
3222
3223        fd = mks_tempfile_ts(&temp->tempfile, template.buf, strlen(base) + 1);
3224        if (fd < 0)
3225                die_errno("unable to create temp-file");
3226        if (convert_to_working_tree(path,
3227                        (const char *)blob, (size_t)size, &buf)) {
3228                blob = buf.buf;
3229                size = buf.len;
3230        }
3231        if (write_in_full(fd, blob, size) != size)
3232                die_errno("unable to write temp-file");
3233        close_tempfile(&temp->tempfile);
3234        temp->name = get_tempfile_path(&temp->tempfile);
3235        oid_to_hex_r(temp->hex, oid);
3236        xsnprintf(temp->mode, sizeof(temp->mode), "%06o", mode);
3237        strbuf_release(&buf);
3238        strbuf_release(&template);
3239        free(path_dup);
3240}
3241
3242static struct diff_tempfile *prepare_temp_file(const char *name,
3243                struct diff_filespec *one)
3244{
3245        struct diff_tempfile *temp = claim_diff_tempfile();
3246
3247        if (!DIFF_FILE_VALID(one)) {
3248        not_a_valid_file:
3249                /* A '-' entry produces this for file-2, and
3250                 * a '+' entry produces this for file-1.
3251                 */
3252                temp->name = "/dev/null";
3253                xsnprintf(temp->hex, sizeof(temp->hex), ".");
3254                xsnprintf(temp->mode, sizeof(temp->mode), ".");
3255                return temp;
3256        }
3257
3258        if (!S_ISGITLINK(one->mode) &&
3259            (!one->oid_valid ||
3260             reuse_worktree_file(name, &one->oid, 1))) {
3261                struct stat st;
3262                if (lstat(name, &st) < 0) {
3263                        if (errno == ENOENT)
3264                                goto not_a_valid_file;
3265                        die_errno("stat(%s)", name);
3266                }
3267                if (S_ISLNK(st.st_mode)) {
3268                        struct strbuf sb = STRBUF_INIT;
3269                        if (strbuf_readlink(&sb, name, st.st_size) < 0)
3270                                die_errno("readlink(%s)", name);
3271                        prep_temp_blob(name, temp, sb.buf, sb.len,
3272                                       (one->oid_valid ?
3273                                        &one->oid : &null_oid),
3274                                       (one->oid_valid ?
3275                                        one->mode : S_IFLNK));
3276                        strbuf_release(&sb);
3277                }
3278                else {
3279                        /* we can borrow from the file in the work tree */
3280                        temp->name = name;
3281                        if (!one->oid_valid)
3282                                oid_to_hex_r(temp->hex, &null_oid);
3283                        else
3284                                oid_to_hex_r(temp->hex, &one->oid);
3285                        /* Even though we may sometimes borrow the
3286                         * contents from the work tree, we always want
3287                         * one->mode.  mode is trustworthy even when
3288                         * !(one->oid_valid), as long as
3289                         * DIFF_FILE_VALID(one).
3290                         */
3291                        xsnprintf(temp->mode, sizeof(temp->mode), "%06o", one->mode);
3292                }
3293                return temp;
3294        }
3295        else {
3296                if (diff_populate_filespec(one, 0))
3297                        die("cannot read data blob for %s", one->path);
3298                prep_temp_blob(name, temp, one->data, one->size,
3299                               &one->oid, one->mode);
3300        }
3301        return temp;
3302}
3303
3304static void add_external_diff_name(struct argv_array *argv,
3305                                   const char *name,
3306                                   struct diff_filespec *df)
3307{
3308        struct diff_tempfile *temp = prepare_temp_file(name, df);
3309        argv_array_push(argv, temp->name);
3310        argv_array_push(argv, temp->hex);
3311        argv_array_push(argv, temp->mode);
3312}
3313
3314/* An external diff command takes:
3315 *
3316 * diff-cmd name infile1 infile1-sha1 infile1-mode \
3317 *               infile2 infile2-sha1 infile2-mode [ rename-to ]
3318 *
3319 */
3320static void run_external_diff(const char *pgm,
3321                              const char *name,
3322                              const char *other,
3323                              struct diff_filespec *one,
3324                              struct diff_filespec *two,
3325                              const char *xfrm_msg,
3326                              int complete_rewrite,
3327                              struct diff_options *o)
3328{
3329        struct argv_array argv = ARGV_ARRAY_INIT;
3330        struct argv_array env = ARGV_ARRAY_INIT;
3331        struct diff_queue_struct *q = &diff_queued_diff;
3332
3333        argv_array_push(&argv, pgm);
3334        argv_array_push(&argv, name);
3335
3336        if (one && two) {
3337                add_external_diff_name(&argv, name, one);
3338                if (!other)
3339                        add_external_diff_name(&argv, name, two);
3340                else {
3341                        add_external_diff_name(&argv, other, two);
3342                        argv_array_push(&argv, other);
3343                        argv_array_push(&argv, xfrm_msg);
3344                }
3345        }
3346
3347        argv_array_pushf(&env, "GIT_DIFF_PATH_COUNTER=%d", ++o->diff_path_counter);
3348        argv_array_pushf(&env, "GIT_DIFF_PATH_TOTAL=%d", q->nr);
3349
3350        if (run_command_v_opt_cd_env(argv.argv, RUN_USING_SHELL, NULL, env.argv))
3351                die(_("external diff died, stopping at %s"), name);
3352
3353        remove_tempfile();
3354        argv_array_clear(&argv);
3355        argv_array_clear(&env);
3356}
3357
3358static int similarity_index(struct diff_filepair *p)
3359{
3360        return p->score * 100 / MAX_SCORE;
3361}
3362
3363static const char *diff_abbrev_oid(const struct object_id *oid, int abbrev)
3364{
3365        if (startup_info->have_repository)
3366                return find_unique_abbrev(oid->hash, abbrev);
3367        else {
3368                char *hex = oid_to_hex(oid);
3369                if (abbrev < 0)
3370                        abbrev = FALLBACK_DEFAULT_ABBREV;
3371                if (abbrev > GIT_SHA1_HEXSZ)
3372                        die("BUG: oid abbreviation out of range: %d", abbrev);
3373                if (abbrev)
3374                        hex[abbrev] = '\0';
3375                return hex;
3376        }
3377}
3378
3379static void fill_metainfo(struct strbuf *msg,
3380                          const char *name,
3381                          const char *other,
3382                          struct diff_filespec *one,
3383                          struct diff_filespec *two,
3384                          struct diff_options *o,
3385                          struct diff_filepair *p,
3386                          int *must_show_header,
3387                          int use_color)
3388{
3389        const char *set = diff_get_color(use_color, DIFF_METAINFO);
3390        const char *reset = diff_get_color(use_color, DIFF_RESET);
3391        const char *line_prefix = diff_line_prefix(o);
3392
3393        *must_show_header = 1;
3394        strbuf_init(msg, PATH_MAX * 2 + 300);
3395        switch (p->status) {
3396        case DIFF_STATUS_COPIED:
3397                strbuf_addf(msg, "%s%ssimilarity index %d%%",
3398                            line_prefix, set, similarity_index(p));
3399                strbuf_addf(msg, "%s\n%s%scopy from ",
3400                            reset,  line_prefix, set);
3401                quote_c_style(name, msg, NULL, 0);
3402                strbuf_addf(msg, "%s\n%s%scopy to ", reset, line_prefix, set);
3403                quote_c_style(other, msg, NULL, 0);
3404                strbuf_addf(msg, "%s\n", reset);
3405                break;
3406        case DIFF_STATUS_RENAMED:
3407                strbuf_addf(msg, "%s%ssimilarity index %d%%",
3408                            line_prefix, set, similarity_index(p));
3409                strbuf_addf(msg, "%s\n%s%srename from ",
3410                            reset, line_prefix, set);
3411                quote_c_style(name, msg, NULL, 0);
3412                strbuf_addf(msg, "%s\n%s%srename to ",
3413                            reset, line_prefix, set);
3414                quote_c_style(other, msg, NULL, 0);
3415                strbuf_addf(msg, "%s\n", reset);
3416                break;
3417        case DIFF_STATUS_MODIFIED:
3418                if (p->score) {
3419                        strbuf_addf(msg, "%s%sdissimilarity index %d%%%s\n",
3420                                    line_prefix,
3421                                    set, similarity_index(p), reset);
3422                        break;
3423                }
3424                /* fallthru */
3425        default:
3426                *must_show_header = 0;
3427        }
3428        if (one && two && oidcmp(&one->oid, &two->oid)) {
3429                int abbrev = DIFF_OPT_TST(o, FULL_INDEX) ? 40 : DEFAULT_ABBREV;
3430
3431                if (DIFF_OPT_TST(o, BINARY)) {
3432                        mmfile_t mf;
3433                        if ((!fill_mmfile(&mf, one) && diff_filespec_is_binary(one)) ||
3434                            (!fill_mmfile(&mf, two) && diff_filespec_is_binary(two)))
3435                                abbrev = 40;
3436                }
3437                strbuf_addf(msg, "%s%sindex %s..%s", line_prefix, set,
3438                            diff_abbrev_oid(&one->oid, abbrev),
3439                            diff_abbrev_oid(&two->oid, abbrev));
3440                if (one->mode == two->mode)
3441                        strbuf_addf(msg, " %06o", one->mode);
3442                strbuf_addf(msg, "%s\n", reset);
3443        }
3444}
3445
3446static void run_diff_cmd(const char *pgm,
3447                         const char *name,
3448                         const char *other,
3449                         const char *attr_path,
3450                         struct diff_filespec *one,
3451                         struct diff_filespec *two,
3452                         struct strbuf *msg,
3453                         struct diff_options *o,
3454                         struct diff_filepair *p)
3455{
3456        const char *xfrm_msg = NULL;
3457        int complete_rewrite = (p->status == DIFF_STATUS_MODIFIED) && p->score;
3458        int must_show_header = 0;
3459
3460
3461        if (DIFF_OPT_TST(o, ALLOW_EXTERNAL)) {
3462                struct userdiff_driver *drv = userdiff_find_by_path(attr_path);
3463                if (drv && drv->external)
3464                        pgm = drv->external;
3465        }
3466
3467        if (msg) {
3468                /*
3469                 * don't use colors when the header is intended for an
3470                 * external diff driver
3471                 */
3472                fill_metainfo(msg, name, other, one, two, o, p,
3473                              &must_show_header,
3474                              want_color(o->use_color) && !pgm);
3475                xfrm_msg = msg->len ? msg->buf : NULL;
3476        }
3477
3478        if (pgm) {
3479                run_external_diff(pgm, name, other, one, two, xfrm_msg,
3480                                  complete_rewrite, o);
3481                return;
3482        }
3483        if (one && two)
3484                builtin_diff(name, other ? other : name,
3485                             one, two, xfrm_msg, must_show_header,
3486                             o, complete_rewrite);
3487        else
3488                fprintf(o->file, "* Unmerged path %s\n", name);
3489}
3490
3491static void diff_fill_oid_info(struct diff_filespec *one)
3492{
3493        if (DIFF_FILE_VALID(one)) {
3494                if (!one->oid_valid) {
3495                        struct stat st;
3496                        if (one->is_stdin) {
3497                                oidclr(&one->oid);
3498                                return;
3499                        }
3500                        if (lstat(one->path, &st) < 0)
3501                                die_errno("stat '%s'", one->path);
3502                        if (index_path(one->oid.hash, one->path, &st, 0))
3503                                die("cannot hash %s", one->path);
3504                }
3505        }
3506        else
3507                oidclr(&one->oid);
3508}
3509
3510static void strip_prefix(int prefix_length, const char **namep, const char **otherp)
3511{
3512        /* Strip the prefix but do not molest /dev/null and absolute paths */
3513        if (*namep && **namep != '/') {
3514                *namep += prefix_length;
3515                if (**namep == '/')
3516                        ++*namep;
3517        }
3518        if (*otherp && **otherp != '/') {
3519                *otherp += prefix_length;
3520                if (**otherp == '/')
3521                        ++*otherp;
3522        }
3523}
3524
3525static void run_diff(struct diff_filepair *p, struct diff_options *o)
3526{
3527        const char *pgm = external_diff();
3528        struct strbuf msg;
3529        struct diff_filespec *one = p->one;
3530        struct diff_filespec *two = p->two;
3531        const char *name;
3532        const char *other;
3533        const char *attr_path;
3534
3535        name  = one->path;
3536        other = (strcmp(name, two->path) ? two->path : NULL);
3537        attr_path = name;
3538        if (o->prefix_length)
3539                strip_prefix(o->prefix_length, &name, &other);
3540
3541        if (!DIFF_OPT_TST(o, ALLOW_EXTERNAL))
3542                pgm = NULL;
3543
3544        if (DIFF_PAIR_UNMERGED(p)) {
3545                run_diff_cmd(pgm, name, NULL, attr_path,
3546                             NULL, NULL, NULL, o, p);
3547                return;
3548        }
3549
3550        diff_fill_oid_info(one);
3551        diff_fill_oid_info(two);
3552
3553        if (!pgm &&
3554            DIFF_FILE_VALID(one) && DIFF_FILE_VALID(two) &&
3555            (S_IFMT & one->mode) != (S_IFMT & two->mode)) {
3556                /*
3557                 * a filepair that changes between file and symlink
3558                 * needs to be split into deletion and creation.
3559                 */
3560                struct diff_filespec *null = alloc_filespec(two->path);
3561                run_diff_cmd(NULL, name, other, attr_path,
3562                             one, null, &msg, o, p);
3563                free(null);
3564                strbuf_release(&msg);
3565
3566                null = alloc_filespec(one->path);
3567                run_diff_cmd(NULL, name, other, attr_path,
3568                             null, two, &msg, o, p);
3569                free(null);
3570        }
3571        else
3572                run_diff_cmd(pgm, name, other, attr_path,
3573                             one, two, &msg, o, p);
3574
3575        strbuf_release(&msg);
3576}
3577
3578static void run_diffstat(struct diff_filepair *p, struct diff_options *o,
3579                         struct diffstat_t *diffstat)
3580{
3581        const char *name;
3582        const char *other;
3583
3584        if (DIFF_PAIR_UNMERGED(p)) {
3585                /* unmerged */
3586                builtin_diffstat(p->one->path, NULL, NULL, NULL, diffstat, o, p);
3587                return;
3588        }
3589
3590        name = p->one->path;
3591        other = (strcmp(name, p->two->path) ? p->two->path : NULL);
3592
3593        if (o->prefix_length)
3594                strip_prefix(o->prefix_length, &name, &other);
3595
3596        diff_fill_oid_info(p->one);
3597        diff_fill_oid_info(p->two);
3598
3599        builtin_diffstat(name, other, p->one, p->two, diffstat, o, p);
3600}
3601
3602static void run_checkdiff(struct diff_filepair *p, struct diff_options *o)
3603{
3604        const char *name;
3605        const char *other;
3606        const char *attr_path;
3607
3608        if (DIFF_PAIR_UNMERGED(p)) {
3609                /* unmerged */
3610                return;
3611        }
3612
3613        name = p->one->path;
3614        other = (strcmp(name, p->two->path) ? p->two->path : NULL);
3615        attr_path = other ? other : name;
3616
3617        if (o->prefix_length)
3618                strip_prefix(o->prefix_length, &name, &other);
3619
3620        diff_fill_oid_info(p->one);
3621        diff_fill_oid_info(p->two);
3622
3623        builtin_checkdiff(name, other, attr_path, p->one, p->two, o);
3624}
3625
3626void diff_setup(struct diff_options *options)
3627{
3628        memcpy(options, &default_diff_options, sizeof(*options));
3629
3630        options->file = stdout;
3631
3632        options->abbrev = DEFAULT_ABBREV;
3633        options->line_termination = '\n';
3634        options->break_opt = -1;
3635        options->rename_limit = -1;
3636        options->dirstat_permille = diff_dirstat_permille_default;
3637        options->context = diff_context_default;
3638        options->interhunkcontext = diff_interhunk_context_default;
3639        options->ws_error_highlight = ws_error_highlight_default;
3640        DIFF_OPT_SET(options, RENAME_EMPTY);
3641
3642        /* pathchange left =NULL by default */
3643        options->change = diff_change;
3644        options->add_remove = diff_addremove;
3645        options->use_color = diff_use_color_default;
3646        options->detect_rename = diff_detect_rename_default;
3647        options->xdl_opts |= diff_algorithm;
3648        if (diff_indent_heuristic)
3649                DIFF_XDL_SET(options, INDENT_HEURISTIC);
3650
3651        options->orderfile = diff_order_file_cfg;
3652
3653        if (diff_no_prefix) {
3654                options->a_prefix = options->b_prefix = "";
3655        } else if (!diff_mnemonic_prefix) {
3656                options->a_prefix = "a/";
3657                options->b_prefix = "b/";
3658        }
3659}
3660
3661void diff_setup_done(struct diff_options *options)
3662{
3663        int count = 0;
3664
3665        if (options->set_default)
3666                options->set_default(options);
3667
3668        if (options->output_format & DIFF_FORMAT_NAME)
3669                count++;
3670        if (options->output_format & DIFF_FORMAT_NAME_STATUS)
3671                count++;
3672        if (options->output_format & DIFF_FORMAT_CHECKDIFF)
3673                count++;
3674        if (options->output_format & DIFF_FORMAT_NO_OUTPUT)
3675                count++;
3676        if (count > 1)
3677                die(_("--name-only, --name-status, --check and -s are mutually exclusive"));
3678
3679        /*
3680         * Most of the time we can say "there are changes"
3681         * only by checking if there are changed paths, but
3682         * --ignore-whitespace* options force us to look
3683         * inside contents.
3684         */
3685
3686        if (DIFF_XDL_TST(options, IGNORE_WHITESPACE) ||
3687            DIFF_XDL_TST(options, IGNORE_WHITESPACE_CHANGE) ||
3688            DIFF_XDL_TST(options, IGNORE_WHITESPACE_AT_EOL))
3689                DIFF_OPT_SET(options, DIFF_FROM_CONTENTS);
3690        else
3691                DIFF_OPT_CLR(options, DIFF_FROM_CONTENTS);
3692
3693        if (DIFF_OPT_TST(options, FIND_COPIES_HARDER))
3694                options->detect_rename = DIFF_DETECT_COPY;
3695
3696        if (!DIFF_OPT_TST(options, RELATIVE_NAME))
3697                options->prefix = NULL;
3698        if (options->prefix)
3699                options->prefix_length = strlen(options->prefix);
3700        else
3701                options->prefix_length = 0;
3702
3703        if (options->output_format & (DIFF_FORMAT_NAME |
3704                                      DIFF_FORMAT_NAME_STATUS |
3705                                      DIFF_FORMAT_CHECKDIFF |
3706                                      DIFF_FORMAT_NO_OUTPUT))
3707                options->output_format &= ~(DIFF_FORMAT_RAW |
3708                                            DIFF_FORMAT_NUMSTAT |
3709                                            DIFF_FORMAT_DIFFSTAT |
3710                                            DIFF_FORMAT_SHORTSTAT |
3711                                            DIFF_FORMAT_DIRSTAT |
3712                                            DIFF_FORMAT_SUMMARY |
3713                                            DIFF_FORMAT_PATCH);
3714
3715        /*
3716         * These cases always need recursive; we do not drop caller-supplied
3717         * recursive bits for other formats here.
3718         */
3719        if (options->output_format & (DIFF_FORMAT_PATCH |
3720                                      DIFF_FORMAT_NUMSTAT |
3721                                      DIFF_FORMAT_DIFFSTAT |
3722                                      DIFF_FORMAT_SHORTSTAT |
3723                                      DIFF_FORMAT_DIRSTAT |
3724                                      DIFF_FORMAT_SUMMARY |
3725                                      DIFF_FORMAT_CHECKDIFF))
3726                DIFF_OPT_SET(options, RECURSIVE);
3727        /*
3728         * Also pickaxe would not work very well if you do not say recursive
3729         */
3730        if (options->pickaxe)
3731                DIFF_OPT_SET(options, RECURSIVE);
3732        /*
3733         * When patches are generated, submodules diffed against the work tree
3734         * must be checked for dirtiness too so it can be shown in the output
3735         */
3736        if (options->output_format & DIFF_FORMAT_PATCH)
3737                DIFF_OPT_SET(options, DIRTY_SUBMODULES);
3738
3739        if (options->detect_rename && options->rename_limit < 0)
3740                options->rename_limit = diff_rename_limit_default;
3741        if (options->setup & DIFF_SETUP_USE_CACHE) {
3742                if (!active_cache)
3743                        /* read-cache does not die even when it fails
3744                         * so it is safe for us to do this here.  Also
3745                         * it does not smudge active_cache or active_nr
3746                         * when it fails, so we do not have to worry about
3747                         * cleaning it up ourselves either.
3748                         */
3749                        read_cache();
3750        }
3751        if (40 < options->abbrev)
3752                options->abbrev = 40; /* full */
3753
3754        /*
3755         * It does not make sense to show the first hit we happened
3756         * to have found.  It does not make sense not to return with
3757         * exit code in such a case either.
3758         */
3759        if (DIFF_OPT_TST(options, QUICK)) {
3760                options->output_format = DIFF_FORMAT_NO_OUTPUT;
3761                DIFF_OPT_SET(options, EXIT_WITH_STATUS);
3762        }
3763
3764        options->diff_path_counter = 0;
3765
3766        if (DIFF_OPT_TST(options, FOLLOW_RENAMES) && options->pathspec.nr != 1)
3767                die(_("--follow requires exactly one pathspec"));
3768}
3769
3770static int opt_arg(const char *arg, int arg_short, const char *arg_long, int *val)
3771{
3772        char c, *eq;
3773        int len;
3774
3775        if (*arg != '-')
3776                return 0;
3777        c = *++arg;
3778        if (!c)
3779                return 0;
3780        if (c == arg_short) {
3781                c = *++arg;
3782                if (!c)
3783                        return 1;
3784                if (val && isdigit(c)) {
3785                        char *end;
3786                        int n = strtoul(arg, &end, 10);
3787                        if (*end)
3788                                return 0;
3789                        *val = n;
3790                        return 1;
3791                }
3792                return 0;
3793        }
3794        if (c != '-')
3795                return 0;
3796        arg++;
3797        eq = strchrnul(arg, '=');
3798        len = eq - arg;
3799        if (!len || strncmp(arg, arg_long, len))
3800                return 0;
3801        if (*eq) {
3802                int n;
3803                char *end;
3804                if (!isdigit(*++eq))
3805                        return 0;
3806                n = strtoul(eq, &end, 10);
3807                if (*end)
3808                        return 0;
3809                *val = n;
3810        }
3811        return 1;
3812}
3813
3814static int diff_scoreopt_parse(const char *opt);
3815
3816static inline int short_opt(char opt, const char **argv,
3817                            const char **optarg)
3818{
3819        const char *arg = argv[0];
3820        if (arg[0] != '-' || arg[1] != opt)
3821                return 0;
3822        if (arg[2] != '\0') {
3823                *optarg = arg + 2;
3824                return 1;
3825        }
3826        if (!argv[1])
3827                die("Option '%c' requires a value", opt);
3828        *optarg = argv[1];
3829        return 2;
3830}
3831
3832int parse_long_opt(const char *opt, const char **argv,
3833                   const char **optarg)
3834{
3835        const char *arg = argv[0];
3836        if (!skip_prefix(arg, "--", &arg))
3837                return 0;
3838        if (!skip_prefix(arg, opt, &arg))
3839                return 0;
3840        if (*arg == '=') { /* stuck form: --option=value */
3841                *optarg = arg + 1;
3842                return 1;
3843        }
3844        if (*arg != '\0')
3845                return 0;
3846        /* separate form: --option value */
3847        if (!argv[1])
3848                die("Option '--%s' requires a value", opt);
3849        *optarg = argv[1];
3850        return 2;
3851}
3852
3853static int stat_opt(struct diff_options *options, const char **av)
3854{
3855        const char *arg = av[0];
3856        char *end;
3857        int width = options->stat_width;
3858        int name_width = options->stat_name_width;
3859        int graph_width = options->stat_graph_width;
3860        int count = options->stat_count;
3861        int argcount = 1;
3862
3863        if (!skip_prefix(arg, "--stat", &arg))
3864                die("BUG: stat option does not begin with --stat: %s", arg);
3865        end = (char *)arg;
3866
3867        switch (*arg) {
3868        case '-':
3869                if (skip_prefix(arg, "-width", &arg)) {
3870                        if (*arg == '=')
3871                                width = strtoul(arg + 1, &end, 10);
3872                        else if (!*arg && !av[1])
3873                                die_want_option("--stat-width");
3874                        else if (!*arg) {
3875                                width = strtoul(av[1], &end, 10);
3876                                argcount = 2;
3877                        }
3878                } else if (skip_prefix(arg, "-name-width", &arg)) {
3879                        if (*arg == '=')
3880                                name_width = strtoul(arg + 1, &end, 10);
3881                        else if (!*arg && !av[1])
3882                                die_want_option("--stat-name-width");
3883                        else if (!*arg) {
3884                                name_width = strtoul(av[1], &end, 10);
3885                                argcount = 2;
3886                        }
3887                } else if (skip_prefix(arg, "-graph-width", &arg)) {
3888                        if (*arg == '=')
3889                                graph_width = strtoul(arg + 1, &end, 10);
3890                        else if (!*arg && !av[1])
3891                                die_want_option("--stat-graph-width");
3892                        else if (!*arg) {
3893                                graph_width = strtoul(av[1], &end, 10);
3894                                argcount = 2;
3895                        }
3896                } else if (skip_prefix(arg, "-count", &arg)) {
3897                        if (*arg == '=')
3898                                count = strtoul(arg + 1, &end, 10);
3899                        else if (!*arg && !av[1])
3900                                die_want_option("--stat-count");
3901                        else if (!*arg) {
3902                                count = strtoul(av[1], &end, 10);
3903                                argcount = 2;
3904                        }
3905                }
3906                break;
3907        case '=':
3908                width = strtoul(arg+1, &end, 10);
3909                if (*end == ',')
3910                        name_width = strtoul(end+1, &end, 10);
3911                if (*end == ',')
3912                        count = strtoul(end+1, &end, 10);
3913        }
3914
3915        /* Important! This checks all the error cases! */
3916        if (*end)
3917                return 0;
3918        options->output_format |= DIFF_FORMAT_DIFFSTAT;
3919        options->stat_name_width = name_width;
3920        options->stat_graph_width = graph_width;
3921        options->stat_width = width;
3922        options->stat_count = count;
3923        return argcount;
3924}
3925
3926static int parse_dirstat_opt(struct diff_options *options, const char *params)
3927{
3928        struct strbuf errmsg = STRBUF_INIT;
3929        if (parse_dirstat_params(options, params, &errmsg))
3930                die(_("Failed to parse --dirstat/-X option parameter:\n%s"),
3931                    errmsg.buf);
3932        strbuf_release(&errmsg);
3933        /*
3934         * The caller knows a dirstat-related option is given from the command
3935         * line; allow it to say "return this_function();"
3936         */
3937        options->output_format |= DIFF_FORMAT_DIRSTAT;
3938        return 1;
3939}
3940
3941static int parse_submodule_opt(struct diff_options *options, const char *value)
3942{
3943        if (parse_submodule_params(options, value))
3944                die(_("Failed to parse --submodule option parameter: '%s'"),
3945                        value);
3946        return 1;
3947}
3948
3949static const char diff_status_letters[] = {
3950        DIFF_STATUS_ADDED,
3951        DIFF_STATUS_COPIED,
3952        DIFF_STATUS_DELETED,
3953        DIFF_STATUS_MODIFIED,
3954        DIFF_STATUS_RENAMED,
3955        DIFF_STATUS_TYPE_CHANGED,
3956        DIFF_STATUS_UNKNOWN,
3957        DIFF_STATUS_UNMERGED,
3958        DIFF_STATUS_FILTER_AON,
3959        DIFF_STATUS_FILTER_BROKEN,
3960        '\0',
3961};
3962
3963static unsigned int filter_bit['Z' + 1];
3964
3965static void prepare_filter_bits(void)
3966{
3967        int i;
3968
3969        if (!filter_bit[DIFF_STATUS_ADDED]) {
3970                for (i = 0; diff_status_letters[i]; i++)
3971                        filter_bit[(int) diff_status_letters[i]] = (1 << i);
3972        }
3973}
3974
3975static unsigned filter_bit_tst(char status, const struct diff_options *opt)
3976{
3977        return opt->filter & filter_bit[(int) status];
3978}
3979
3980static int parse_diff_filter_opt(const char *optarg, struct diff_options *opt)
3981{
3982        int i, optch;
3983
3984        prepare_filter_bits();
3985
3986        /*
3987         * If there is a negation e.g. 'd' in the input, and we haven't
3988         * initialized the filter field with another --diff-filter, start
3989         * from full set of bits, except for AON.
3990         */
3991        if (!opt->filter) {
3992                for (i = 0; (optch = optarg[i]) != '\0'; i++) {
3993                        if (optch < 'a' || 'z' < optch)
3994                                continue;
3995                        opt->filter = (1 << (ARRAY_SIZE(diff_status_letters) - 1)) - 1;
3996                        opt->filter &= ~filter_bit[DIFF_STATUS_FILTER_AON];
3997                        break;
3998                }
3999        }
4000
4001        for (i = 0; (optch = optarg[i]) != '\0'; i++) {
4002                unsigned int bit;
4003                int negate;
4004
4005                if ('a' <= optch && optch <= 'z') {
4006                        negate = 1;
4007                        optch = toupper(optch);
4008                } else {
4009                        negate = 0;
4010                }
4011
4012                bit = (0 <= optch && optch <= 'Z') ? filter_bit[optch] : 0;
4013                if (!bit)
4014                        return optarg[i];
4015                if (negate)
4016                        opt->filter &= ~bit;
4017                else
4018                        opt->filter |= bit;
4019        }
4020        return 0;
4021}
4022
4023static void enable_patch_output(int *fmt) {
4024        *fmt &= ~DIFF_FORMAT_NO_OUTPUT;
4025        *fmt |= DIFF_FORMAT_PATCH;
4026}
4027
4028static int parse_ws_error_highlight_opt(struct diff_options *opt, const char *arg)
4029{
4030        int val = parse_ws_error_highlight(arg);
4031
4032        if (val < 0) {
4033                error("unknown value after ws-error-highlight=%.*s",
4034                      -1 - val, arg);
4035                return 0;
4036        }
4037        opt->ws_error_highlight = val;
4038        return 1;
4039}
4040
4041int diff_opt_parse(struct diff_options *options,
4042                   const char **av, int ac, const char *prefix)
4043{
4044        const char *arg = av[0];
4045        const char *optarg;
4046        int argcount;
4047
4048        if (!prefix)
4049                prefix = "";
4050
4051        /* Output format options */
4052        if (!strcmp(arg, "-p") || !strcmp(arg, "-u") || !strcmp(arg, "--patch")
4053            || opt_arg(arg, 'U', "unified", &options->context))
4054                enable_patch_output(&options->output_format);
4055        else if (!strcmp(arg, "--raw"))
4056                options->output_format |= DIFF_FORMAT_RAW;
4057        else if (!strcmp(arg, "--patch-with-raw")) {
4058                enable_patch_output(&options->output_format);
4059                options->output_format |= DIFF_FORMAT_RAW;
4060        } else if (!strcmp(arg, "--numstat"))
4061                options->output_format |= DIFF_FORMAT_NUMSTAT;
4062        else if (!strcmp(arg, "--shortstat"))
4063                options->output_format |= DIFF_FORMAT_SHORTSTAT;
4064        else if (!strcmp(arg, "-X") || !strcmp(arg, "--dirstat"))
4065                return parse_dirstat_opt(options, "");
4066        else if (skip_prefix(arg, "-X", &arg))
4067                return parse_dirstat_opt(options, arg);
4068        else if (skip_prefix(arg, "--dirstat=", &arg))
4069                return parse_dirstat_opt(options, arg);
4070        else if (!strcmp(arg, "--cumulative"))
4071                return parse_dirstat_opt(options, "cumulative");
4072        else if (!strcmp(arg, "--dirstat-by-file"))
4073                return parse_dirstat_opt(options, "files");
4074        else if (skip_prefix(arg, "--dirstat-by-file=", &arg)) {
4075                parse_dirstat_opt(options, "files");
4076                return parse_dirstat_opt(options, arg);
4077        }
4078        else if (!strcmp(arg, "--check"))
4079                options->output_format |= DIFF_FORMAT_CHECKDIFF;
4080        else if (!strcmp(arg, "--summary"))
4081                options->output_format |= DIFF_FORMAT_SUMMARY;
4082        else if (!strcmp(arg, "--patch-with-stat")) {
4083                enable_patch_output(&options->output_format);
4084                options->output_format |= DIFF_FORMAT_DIFFSTAT;
4085        } else if (!strcmp(arg, "--name-only"))
4086                options->output_format |= DIFF_FORMAT_NAME;
4087        else if (!strcmp(arg, "--name-status"))
4088                options->output_format |= DIFF_FORMAT_NAME_STATUS;
4089        else if (!strcmp(arg, "-s") || !strcmp(arg, "--no-patch"))
4090                options->output_format |= DIFF_FORMAT_NO_OUTPUT;
4091        else if (starts_with(arg, "--stat"))
4092                /* --stat, --stat-width, --stat-name-width, or --stat-count */
4093                return stat_opt(options, av);
4094
4095        /* renames options */
4096        else if (starts_with(arg, "-B") || starts_with(arg, "--break-rewrites=") ||
4097                 !strcmp(arg, "--break-rewrites")) {
4098                if ((options->break_opt = diff_scoreopt_parse(arg)) == -1)
4099                        return error("invalid argument to -B: %s", arg+2);
4100        }
4101        else if (starts_with(arg, "-M") || starts_with(arg, "--find-renames=") ||
4102                 !strcmp(arg, "--find-renames")) {
4103                if ((options->rename_score = diff_scoreopt_parse(arg)) == -1)
4104                        return error("invalid argument to -M: %s", arg+2);
4105                options->detect_rename = DIFF_DETECT_RENAME;
4106        }
4107        else if (!strcmp(arg, "-D") || !strcmp(arg, "--irreversible-delete")) {
4108                options->irreversible_delete = 1;
4109        }
4110        else if (starts_with(arg, "-C") || starts_with(arg, "--find-copies=") ||
4111                 !strcmp(arg, "--find-copies")) {
4112                if (options->detect_rename == DIFF_DETECT_COPY)
4113                        DIFF_OPT_SET(options, FIND_COPIES_HARDER);
4114                if ((options->rename_score = diff_scoreopt_parse(arg)) == -1)
4115                        return error("invalid argument to -C: %s", arg+2);
4116                options->detect_rename = DIFF_DETECT_COPY;
4117        }
4118        else if (!strcmp(arg, "--no-renames"))
4119                options->detect_rename = 0;
4120        else if (!strcmp(arg, "--rename-empty"))
4121                DIFF_OPT_SET(options, RENAME_EMPTY);
4122        else if (!strcmp(arg, "--no-rename-empty"))
4123                DIFF_OPT_CLR(options, RENAME_EMPTY);
4124        else if (!strcmp(arg, "--relative"))
4125                DIFF_OPT_SET(options, RELATIVE_NAME);
4126        else if (skip_prefix(arg, "--relative=", &arg)) {
4127                DIFF_OPT_SET(options, RELATIVE_NAME);
4128                options->prefix = arg;
4129        }
4130
4131        /* xdiff options */
4132        else if (!strcmp(arg, "--minimal"))
4133                DIFF_XDL_SET(options, NEED_MINIMAL);
4134        else if (!strcmp(arg, "--no-minimal"))
4135                DIFF_XDL_CLR(options, NEED_MINIMAL);
4136        else if (!strcmp(arg, "-w") || !strcmp(arg, "--ignore-all-space"))
4137                DIFF_XDL_SET(options, IGNORE_WHITESPACE);
4138        else if (!strcmp(arg, "-b") || !strcmp(arg, "--ignore-space-change"))
4139                DIFF_XDL_SET(options, IGNORE_WHITESPACE_CHANGE);
4140        else if (!strcmp(arg, "--ignore-space-at-eol"))
4141                DIFF_XDL_SET(options, IGNORE_WHITESPACE_AT_EOL);
4142        else if (!strcmp(arg, "--ignore-blank-lines"))
4143                DIFF_XDL_SET(options, IGNORE_BLANK_LINES);
4144        else if (!strcmp(arg, "--indent-heuristic"))
4145                DIFF_XDL_SET(options, INDENT_HEURISTIC);
4146        else if (!strcmp(arg, "--no-indent-heuristic"))
4147                DIFF_XDL_CLR(options, INDENT_HEURISTIC);
4148        else if (!strcmp(arg, "--patience"))
4149                options->xdl_opts = DIFF_WITH_ALG(options, PATIENCE_DIFF);
4150        else if (!strcmp(arg, "--histogram"))
4151                options->xdl_opts = DIFF_WITH_ALG(options, HISTOGRAM_DIFF);
4152        else if ((argcount = parse_long_opt("diff-algorithm", av, &optarg))) {
4153                long value = parse_algorithm_value(optarg);
4154                if (value < 0)
4155                        return error("option diff-algorithm accepts \"myers\", "
4156                                     "\"minimal\", \"patience\" and \"histogram\"");
4157                /* clear out previous settings */
4158                DIFF_XDL_CLR(options, NEED_MINIMAL);
4159                options->xdl_opts &= ~XDF_DIFF_ALGORITHM_MASK;
4160                options->xdl_opts |= value;
4161                return argcount;
4162        }
4163
4164        /* flags options */
4165        else if (!strcmp(arg, "--binary")) {
4166                enable_patch_output(&options->output_format);
4167                DIFF_OPT_SET(options, BINARY);
4168        }
4169        else if (!strcmp(arg, "--full-index"))
4170                DIFF_OPT_SET(options, FULL_INDEX);
4171        else if (!strcmp(arg, "-a") || !strcmp(arg, "--text"))
4172                DIFF_OPT_SET(options, TEXT);
4173        else if (!strcmp(arg, "-R"))
4174                DIFF_OPT_SET(options, REVERSE_DIFF);
4175        else if (!strcmp(arg, "--find-copies-harder"))
4176                DIFF_OPT_SET(options, FIND_COPIES_HARDER);
4177        else if (!strcmp(arg, "--follow"))
4178                DIFF_OPT_SET(options, FOLLOW_RENAMES);
4179        else if (!strcmp(arg, "--no-follow")) {
4180                DIFF_OPT_CLR(options, FOLLOW_RENAMES);
4181                DIFF_OPT_CLR(options, DEFAULT_FOLLOW_RENAMES);
4182        } else if (!strcmp(arg, "--color"))
4183                options->use_color = 1;
4184        else if (skip_prefix(arg, "--color=", &arg)) {
4185                int value = git_config_colorbool(NULL, arg);
4186                if (value < 0)
4187                        return error("option `color' expects \"always\", \"auto\", or \"never\"");
4188                options->use_color = value;
4189        }
4190        else if (!strcmp(arg, "--no-color"))
4191                options->use_color = 0;
4192        else if (!strcmp(arg, "--color-words")) {
4193                options->use_color = 1;
4194                options->word_diff = DIFF_WORDS_COLOR;
4195        }
4196        else if (skip_prefix(arg, "--color-words=", &arg)) {
4197                options->use_color = 1;
4198                options->word_diff = DIFF_WORDS_COLOR;
4199                options->word_regex = arg;
4200        }
4201        else if (!strcmp(arg, "--word-diff")) {
4202                if (options->word_diff == DIFF_WORDS_NONE)
4203                        options->word_diff = DIFF_WORDS_PLAIN;
4204        }
4205        else if (skip_prefix(arg, "--word-diff=", &arg)) {
4206                if (!strcmp(arg, "plain"))
4207                        options->word_diff = DIFF_WORDS_PLAIN;
4208                else if (!strcmp(arg, "color")) {
4209                        options->use_color = 1;
4210                        options->word_diff = DIFF_WORDS_COLOR;
4211                }
4212                else if (!strcmp(arg, "porcelain"))
4213                        options->word_diff = DIFF_WORDS_PORCELAIN;
4214                else if (!strcmp(arg, "none"))
4215                        options->word_diff = DIFF_WORDS_NONE;
4216                else
4217                        die("bad --word-diff argument: %s", arg);
4218        }
4219        else if ((argcount = parse_long_opt("word-diff-regex", av, &optarg))) {
4220                if (options->word_diff == DIFF_WORDS_NONE)
4221                        options->word_diff = DIFF_WORDS_PLAIN;
4222                options->word_regex = optarg;
4223                return argcount;
4224        }
4225        else if (!strcmp(arg, "--exit-code"))
4226                DIFF_OPT_SET(options, EXIT_WITH_STATUS);
4227        else if (!strcmp(arg, "--quiet"))
4228                DIFF_OPT_SET(options, QUICK);
4229        else if (!strcmp(arg, "--ext-diff"))
4230                DIFF_OPT_SET(options, ALLOW_EXTERNAL);
4231        else if (!strcmp(arg, "--no-ext-diff"))
4232                DIFF_OPT_CLR(options, ALLOW_EXTERNAL);
4233        else if (!strcmp(arg, "--textconv"))
4234                DIFF_OPT_SET(options, ALLOW_TEXTCONV);
4235        else if (!strcmp(arg, "--no-textconv"))
4236                DIFF_OPT_CLR(options, ALLOW_TEXTCONV);
4237        else if (!strcmp(arg, "--ignore-submodules")) {
4238                DIFF_OPT_SET(options, OVERRIDE_SUBMODULE_CONFIG);
4239                handle_ignore_submodules_arg(options, "all");
4240        } else if (skip_prefix(arg, "--ignore-submodules=", &arg)) {
4241                DIFF_OPT_SET(options, OVERRIDE_SUBMODULE_CONFIG);
4242                handle_ignore_submodules_arg(options, arg);
4243        } else if (!strcmp(arg, "--submodule"))
4244                options->submodule_format = DIFF_SUBMODULE_LOG;
4245        else if (skip_prefix(arg, "--submodule=", &arg))
4246                return parse_submodule_opt(options, arg);
4247        else if (skip_prefix(arg, "--ws-error-highlight=", &arg))
4248                return parse_ws_error_highlight_opt(options, arg);
4249        else if (!strcmp(arg, "--ita-invisible-in-index"))
4250                options->ita_invisible_in_index = 1;
4251        else if (!strcmp(arg, "--ita-visible-in-index"))
4252                options->ita_invisible_in_index = 0;
4253
4254        /* misc options */
4255        else if (!strcmp(arg, "-z"))
4256                options->line_termination = 0;
4257        else if ((argcount = short_opt('l', av, &optarg))) {
4258                options->rename_limit = strtoul(optarg, NULL, 10);
4259                return argcount;
4260        }
4261        else if ((argcount = short_opt('S', av, &optarg))) {
4262                options->pickaxe = optarg;
4263                options->pickaxe_opts |= DIFF_PICKAXE_KIND_S;
4264                return argcount;
4265        } else if ((argcount = short_opt('G', av, &optarg))) {
4266                options->pickaxe = optarg;
4267                options->pickaxe_opts |= DIFF_PICKAXE_KIND_G;
4268                return argcount;
4269        }
4270        else if (!strcmp(arg, "--pickaxe-all"))
4271                options->pickaxe_opts |= DIFF_PICKAXE_ALL;
4272        else if (!strcmp(arg, "--pickaxe-regex"))
4273                options->pickaxe_opts |= DIFF_PICKAXE_REGEX;
4274        else if ((argcount = short_opt('O', av, &optarg))) {
4275                options->orderfile = prefix_filename(prefix, optarg);
4276                return argcount;
4277        }
4278        else if ((argcount = parse_long_opt("diff-filter", av, &optarg))) {
4279                int offending = parse_diff_filter_opt(optarg, options);
4280                if (offending)
4281                        die("unknown change class '%c' in --diff-filter=%s",
4282                            offending, optarg);
4283                return argcount;
4284        }
4285        else if (!strcmp(arg, "--no-abbrev"))
4286                options->abbrev = 0;
4287        else if (!strcmp(arg, "--abbrev"))
4288                options->abbrev = DEFAULT_ABBREV;
4289        else if (skip_prefix(arg, "--abbrev=", &arg)) {
4290                options->abbrev = strtoul(arg, NULL, 10);
4291                if (options->abbrev < MINIMUM_ABBREV)
4292                        options->abbrev = MINIMUM_ABBREV;
4293                else if (40 < options->abbrev)
4294                        options->abbrev = 40;
4295        }
4296        else if ((argcount = parse_long_opt("src-prefix", av, &optarg))) {
4297                options->a_prefix = optarg;
4298                return argcount;
4299        }
4300        else if ((argcount = parse_long_opt("line-prefix", av, &optarg))) {
4301                options->line_prefix = optarg;
4302                options->line_prefix_length = strlen(options->line_prefix);
4303                graph_setup_line_prefix(options);
4304                return argcount;
4305        }
4306        else if ((argcount = parse_long_opt("dst-prefix", av, &optarg))) {
4307                options->b_prefix = optarg;
4308                return argcount;
4309        }
4310        else if (!strcmp(arg, "--no-prefix"))
4311                options->a_prefix = options->b_prefix = "";
4312        else if (opt_arg(arg, '\0', "inter-hunk-context",
4313                         &options->interhunkcontext))
4314                ;
4315        else if (!strcmp(arg, "-W"))
4316                DIFF_OPT_SET(options, FUNCCONTEXT);
4317        else if (!strcmp(arg, "--function-context"))
4318                DIFF_OPT_SET(options, FUNCCONTEXT);
4319        else if (!strcmp(arg, "--no-function-context"))
4320                DIFF_OPT_CLR(options, FUNCCONTEXT);
4321        else if ((argcount = parse_long_opt("output", av, &optarg))) {
4322                char *path = prefix_filename(prefix, optarg);
4323                options->file = xfopen(path, "w");
4324                options->close_file = 1;
4325                if (options->use_color != GIT_COLOR_ALWAYS)
4326                        options->use_color = GIT_COLOR_NEVER;
4327                free(path);
4328                return argcount;
4329        } else
4330                return 0;
4331        return 1;
4332}
4333
4334int parse_rename_score(const char **cp_p)
4335{
4336        unsigned long num, scale;
4337        int ch, dot;
4338        const char *cp = *cp_p;
4339
4340        num = 0;
4341        scale = 1;
4342        dot = 0;
4343        for (;;) {
4344                ch = *cp;
4345                if ( !dot && ch == '.' ) {
4346                        scale = 1;
4347                        dot = 1;
4348                } else if ( ch == '%' ) {
4349                        scale = dot ? scale*100 : 100;
4350                        cp++;   /* % is always at the end */
4351                        break;
4352                } else if ( ch >= '0' && ch <= '9' ) {
4353                        if ( scale < 100000 ) {
4354                                scale *= 10;
4355                                num = (num*10) + (ch-'0');
4356                        }
4357                } else {
4358                        break;
4359                }
4360                cp++;
4361        }
4362        *cp_p = cp;
4363
4364        /* user says num divided by scale and we say internally that
4365         * is MAX_SCORE * num / scale.
4366         */
4367        return (int)((num >= scale) ? MAX_SCORE : (MAX_SCORE * num / scale));
4368}
4369
4370static int diff_scoreopt_parse(const char *opt)
4371{
4372        int opt1, opt2, cmd;
4373
4374        if (*opt++ != '-')
4375                return -1;
4376        cmd = *opt++;
4377        if (cmd == '-') {
4378                /* convert the long-form arguments into short-form versions */
4379                if (skip_prefix(opt, "break-rewrites", &opt)) {
4380                        if (*opt == 0 || *opt++ == '=')
4381                                cmd = 'B';
4382                } else if (skip_prefix(opt, "find-copies", &opt)) {
4383                        if (*opt == 0 || *opt++ == '=')
4384                                cmd = 'C';
4385                } else if (skip_prefix(opt, "find-renames", &opt)) {
4386                        if (*opt == 0 || *opt++ == '=')
4387                                cmd = 'M';
4388                }
4389        }
4390        if (cmd != 'M' && cmd != 'C' && cmd != 'B')
4391                return -1; /* that is not a -M, -C, or -B option */
4392
4393        opt1 = parse_rename_score(&opt);
4394        if (cmd != 'B')
4395                opt2 = 0;
4396        else {
4397                if (*opt == 0)
4398                        opt2 = 0;
4399                else if (*opt != '/')
4400                        return -1; /* we expect -B80/99 or -B80 */
4401                else {
4402                        opt++;
4403                        opt2 = parse_rename_score(&opt);
4404                }
4405        }
4406        if (*opt != 0)
4407                return -1;
4408        return opt1 | (opt2 << 16);
4409}
4410
4411struct diff_queue_struct diff_queued_diff;
4412
4413void diff_q(struct diff_queue_struct *queue, struct diff_filepair *dp)
4414{
4415        ALLOC_GROW(queue->queue, queue->nr + 1, queue->alloc);
4416        queue->queue[queue->nr++] = dp;
4417}
4418
4419struct diff_filepair *diff_queue(struct diff_queue_struct *queue,
4420                                 struct diff_filespec *one,
4421                                 struct diff_filespec *two)
4422{
4423        struct diff_filepair *dp = xcalloc(1, sizeof(*dp));
4424        dp->one = one;
4425        dp->two = two;
4426        if (queue)
4427                diff_q(queue, dp);
4428        return dp;
4429}
4430
4431void diff_free_filepair(struct diff_filepair *p)
4432{
4433        free_filespec(p->one);
4434        free_filespec(p->two);
4435        free(p);
4436}
4437
4438const char *diff_aligned_abbrev(const struct object_id *oid, int len)
4439{
4440        int abblen;
4441        const char *abbrev;
4442
4443        if (len == GIT_SHA1_HEXSZ)
4444                return oid_to_hex(oid);
4445
4446        abbrev = diff_abbrev_oid(oid, len);
4447        abblen = strlen(abbrev);
4448
4449        /*
4450         * In well-behaved cases, where the abbbreviated result is the
4451         * same as the requested length, append three dots after the
4452         * abbreviation (hence the whole logic is limited to the case
4453         * where abblen < 37); when the actual abbreviated result is a
4454         * bit longer than the requested length, we reduce the number
4455         * of dots so that they match the well-behaved ones.  However,
4456         * if the actual abbreviation is longer than the requested
4457         * length by more than three, we give up on aligning, and add
4458         * three dots anyway, to indicate that the output is not the
4459         * full object name.  Yes, this may be suboptimal, but this
4460         * appears only in "diff --raw --abbrev" output and it is not
4461         * worth the effort to change it now.  Note that this would
4462         * likely to work fine when the automatic sizing of default
4463         * abbreviation length is used--we would be fed -1 in "len" in
4464         * that case, and will end up always appending three-dots, but
4465         * the automatic sizing is supposed to give abblen that ensures
4466         * uniqueness across all objects (statistically speaking).
4467         */
4468        if (abblen < GIT_SHA1_HEXSZ - 3) {
4469                static char hex[GIT_MAX_HEXSZ + 1];
4470                if (len < abblen && abblen <= len + 2)
4471                        xsnprintf(hex, sizeof(hex), "%s%.*s", abbrev, len+3-abblen, "..");
4472                else
4473                        xsnprintf(hex, sizeof(hex), "%s...", abbrev);
4474                return hex;
4475        }
4476
4477        return oid_to_hex(oid);
4478}
4479
4480static void diff_flush_raw(struct diff_filepair *p, struct diff_options *opt)
4481{
4482        int line_termination = opt->line_termination;
4483        int inter_name_termination = line_termination ? '\t' : '\0';
4484
4485        fprintf(opt->file, "%s", diff_line_prefix(opt));
4486        if (!(opt->output_format & DIFF_FORMAT_NAME_STATUS)) {
4487                fprintf(opt->file, ":%06o %06o %s ", p->one->mode, p->two->mode,
4488                        diff_aligned_abbrev(&p->one->oid, opt->abbrev));
4489                fprintf(opt->file, "%s ",
4490                        diff_aligned_abbrev(&p->two->oid, opt->abbrev));
4491        }
4492        if (p->score) {
4493                fprintf(opt->file, "%c%03d%c", p->status, similarity_index(p),
4494                        inter_name_termination);
4495        } else {
4496                fprintf(opt->file, "%c%c", p->status, inter_name_termination);
4497        }
4498
4499        if (p->status == DIFF_STATUS_COPIED ||
4500            p->status == DIFF_STATUS_RENAMED) {
4501                const char *name_a, *name_b;
4502                name_a = p->one->path;
4503                name_b = p->two->path;
4504                strip_prefix(opt->prefix_length, &name_a, &name_b);
4505                write_name_quoted(name_a, opt->file, inter_name_termination);
4506                write_name_quoted(name_b, opt->file, line_termination);
4507        } else {
4508                const char *name_a, *name_b;
4509                name_a = p->one->mode ? p->one->path : p->two->path;
4510                name_b = NULL;
4511                strip_prefix(opt->prefix_length, &name_a, &name_b);
4512                write_name_quoted(name_a, opt->file, line_termination);
4513        }
4514}
4515
4516int diff_unmodified_pair(struct diff_filepair *p)
4517{
4518        /* This function is written stricter than necessary to support
4519         * the currently implemented transformers, but the idea is to
4520         * let transformers to produce diff_filepairs any way they want,
4521         * and filter and clean them up here before producing the output.
4522         */
4523        struct diff_filespec *one = p->one, *two = p->two;
4524
4525        if (DIFF_PAIR_UNMERGED(p))
4526                return 0; /* unmerged is interesting */
4527
4528        /* deletion, addition, mode or type change
4529         * and rename are all interesting.
4530         */
4531        if (DIFF_FILE_VALID(one) != DIFF_FILE_VALID(two) ||
4532            DIFF_PAIR_MODE_CHANGED(p) ||
4533            strcmp(one->path, two->path))
4534                return 0;
4535
4536        /* both are valid and point at the same path.  that is, we are
4537         * dealing with a change.
4538         */
4539        if (one->oid_valid && two->oid_valid &&
4540            !oidcmp(&one->oid, &two->oid) &&
4541            !one->dirty_submodule && !two->dirty_submodule)
4542                return 1; /* no change */
4543        if (!one->oid_valid && !two->oid_valid)
4544                return 1; /* both look at the same file on the filesystem. */
4545        return 0;
4546}
4547
4548static void diff_flush_patch(struct diff_filepair *p, struct diff_options *o)
4549{
4550        if (diff_unmodified_pair(p))
4551                return;
4552
4553        if ((DIFF_FILE_VALID(p->one) && S_ISDIR(p->one->mode)) ||
4554            (DIFF_FILE_VALID(p->two) && S_ISDIR(p->two->mode)))
4555                return; /* no tree diffs in patch format */
4556
4557        run_diff(p, o);
4558}
4559
4560static void diff_flush_stat(struct diff_filepair *p, struct diff_options *o,
4561                            struct diffstat_t *diffstat)
4562{
4563        if (diff_unmodified_pair(p))
4564                return;
4565
4566        if ((DIFF_FILE_VALID(p->one) && S_ISDIR(p->one->mode)) ||
4567            (DIFF_FILE_VALID(p->two) && S_ISDIR(p->two->mode)))
4568                return; /* no useful stat for tree diffs */
4569
4570        run_diffstat(p, o, diffstat);
4571}
4572
4573static void diff_flush_checkdiff(struct diff_filepair *p,
4574                struct diff_options *o)
4575{
4576        if (diff_unmodified_pair(p))
4577                return;
4578
4579        if ((DIFF_FILE_VALID(p->one) && S_ISDIR(p->one->mode)) ||
4580            (DIFF_FILE_VALID(p->two) && S_ISDIR(p->two->mode)))
4581                return; /* nothing to check in tree diffs */
4582
4583        run_checkdiff(p, o);
4584}
4585
4586int diff_queue_is_empty(void)
4587{
4588        struct diff_queue_struct *q = &diff_queued_diff;
4589        int i;
4590        for (i = 0; i < q->nr; i++)
4591                if (!diff_unmodified_pair(q->queue[i]))
4592                        return 0;
4593        return 1;
4594}
4595
4596#if DIFF_DEBUG
4597void diff_debug_filespec(struct diff_filespec *s, int x, const char *one)
4598{
4599        fprintf(stderr, "queue[%d] %s (%s) %s %06o %s\n",
4600                x, one ? one : "",
4601                s->path,
4602                DIFF_FILE_VALID(s) ? "valid" : "invalid",
4603                s->mode,
4604                s->oid_valid ? oid_to_hex(&s->oid) : "");
4605        fprintf(stderr, "queue[%d] %s size %lu\n",
4606                x, one ? one : "",
4607                s->size);
4608}
4609
4610void diff_debug_filepair(const struct diff_filepair *p, int i)
4611{
4612        diff_debug_filespec(p->one, i, "one");
4613        diff_debug_filespec(p->two, i, "two");
4614        fprintf(stderr, "score %d, status %c rename_used %d broken %d\n",
4615                p->score, p->status ? p->status : '?',
4616                p->one->rename_used, p->broken_pair);
4617}
4618
4619void diff_debug_queue(const char *msg, struct diff_queue_struct *q)
4620{
4621        int i;
4622        if (msg)
4623                fprintf(stderr, "%s\n", msg);
4624        fprintf(stderr, "q->nr = %d\n", q->nr);
4625        for (i = 0; i < q->nr; i++) {
4626                struct diff_filepair *p = q->queue[i];
4627                diff_debug_filepair(p, i);
4628        }
4629}
4630#endif
4631
4632static void diff_resolve_rename_copy(void)
4633{
4634        int i;
4635        struct diff_filepair *p;
4636        struct diff_queue_struct *q = &diff_queued_diff;
4637
4638        diff_debug_queue("resolve-rename-copy", q);
4639
4640        for (i = 0; i < q->nr; i++) {
4641                p = q->queue[i];
4642                p->status = 0; /* undecided */
4643                if (DIFF_PAIR_UNMERGED(p))
4644                        p->status = DIFF_STATUS_UNMERGED;
4645                else if (!DIFF_FILE_VALID(p->one))
4646                        p->status = DIFF_STATUS_ADDED;
4647                else if (!DIFF_FILE_VALID(p->two))
4648                        p->status = DIFF_STATUS_DELETED;
4649                else if (DIFF_PAIR_TYPE_CHANGED(p))
4650                        p->status = DIFF_STATUS_TYPE_CHANGED;
4651
4652                /* from this point on, we are dealing with a pair
4653                 * whose both sides are valid and of the same type, i.e.
4654                 * either in-place edit or rename/copy edit.
4655                 */
4656                else if (DIFF_PAIR_RENAME(p)) {
4657                        /*
4658                         * A rename might have re-connected a broken
4659                         * pair up, causing the pathnames to be the
4660                         * same again. If so, that's not a rename at
4661                         * all, just a modification..
4662                         *
4663                         * Otherwise, see if this source was used for
4664                         * multiple renames, in which case we decrement
4665                         * the count, and call it a copy.
4666                         */
4667                        if (!strcmp(p->one->path, p->two->path))
4668                                p->status = DIFF_STATUS_MODIFIED;
4669                        else if (--p->one->rename_used > 0)
4670                                p->status = DIFF_STATUS_COPIED;
4671                        else
4672                                p->status = DIFF_STATUS_RENAMED;
4673                }
4674                else if (oidcmp(&p->one->oid, &p->two->oid) ||
4675                         p->one->mode != p->two->mode ||
4676                         p->one->dirty_submodule ||
4677                         p->two->dirty_submodule ||
4678                         is_null_oid(&p->one->oid))
4679                        p->status = DIFF_STATUS_MODIFIED;
4680                else {
4681                        /* This is a "no-change" entry and should not
4682                         * happen anymore, but prepare for broken callers.
4683                         */
4684                        error("feeding unmodified %s to diffcore",
4685                              p->one->path);
4686                        p->status = DIFF_STATUS_UNKNOWN;
4687                }
4688        }
4689        diff_debug_queue("resolve-rename-copy done", q);
4690}
4691
4692static int check_pair_status(struct diff_filepair *p)
4693{
4694        switch (p->status) {
4695        case DIFF_STATUS_UNKNOWN:
4696                return 0;
4697        case 0:
4698                die("internal error in diff-resolve-rename-copy");
4699        default:
4700                return 1;
4701        }
4702}
4703
4704static void flush_one_pair(struct diff_filepair *p, struct diff_options *opt)
4705{
4706        int fmt = opt->output_format;
4707
4708        if (fmt & DIFF_FORMAT_CHECKDIFF)
4709                diff_flush_checkdiff(p, opt);
4710        else if (fmt & (DIFF_FORMAT_RAW | DIFF_FORMAT_NAME_STATUS))
4711                diff_flush_raw(p, opt);
4712        else if (fmt & DIFF_FORMAT_NAME) {
4713                const char *name_a, *name_b;
4714                name_a = p->two->path;
4715                name_b = NULL;
4716                strip_prefix(opt->prefix_length, &name_a, &name_b);
4717                fprintf(opt->file, "%s", diff_line_prefix(opt));
4718                write_name_quoted(name_a, opt->file, opt->line_termination);
4719        }
4720}
4721
4722static void show_file_mode_name(struct diff_options *opt, const char *newdelete, struct diff_filespec *fs)
4723{
4724        struct strbuf sb = STRBUF_INIT;
4725        if (fs->mode)
4726                strbuf_addf(&sb, " %s mode %06o ", newdelete, fs->mode);
4727        else
4728                strbuf_addf(&sb, " %s ", newdelete);
4729
4730        quote_c_style(fs->path, &sb, NULL, 0);
4731        strbuf_addch(&sb, '\n');
4732        emit_diff_symbol(opt, DIFF_SYMBOL_SUMMARY,
4733                         sb.buf, sb.len, 0);
4734        strbuf_release(&sb);
4735}
4736
4737static void show_mode_change(struct diff_options *opt, struct diff_filepair *p,
4738                int show_name)
4739{
4740        if (p->one->mode && p->two->mode && p->one->mode != p->two->mode) {
4741                struct strbuf sb = STRBUF_INIT;
4742                strbuf_addf(&sb, " mode change %06o => %06o",
4743                            p->one->mode, p->two->mode);
4744                if (show_name) {
4745                        strbuf_addch(&sb, ' ');
4746                        quote_c_style(p->two->path, &sb, NULL, 0);
4747                }
4748                emit_diff_symbol(opt, DIFF_SYMBOL_SUMMARY,
4749                                 sb.buf, sb.len, 0);
4750                strbuf_release(&sb);
4751        }
4752}
4753
4754static void show_rename_copy(struct diff_options *opt, const char *renamecopy,
4755                struct diff_filepair *p)
4756{
4757        struct strbuf sb = STRBUF_INIT;
4758        char *names = pprint_rename(p->one->path, p->two->path);
4759        strbuf_addf(&sb, " %s %s (%d%%)\n",
4760                        renamecopy, names, similarity_index(p));
4761        free(names);
4762        emit_diff_symbol(opt, DIFF_SYMBOL_SUMMARY,
4763                                 sb.buf, sb.len, 0);
4764        show_mode_change(opt, p, 0);
4765}
4766
4767static void diff_summary(struct diff_options *opt, struct diff_filepair *p)
4768{
4769        switch(p->status) {
4770        case DIFF_STATUS_DELETED:
4771                show_file_mode_name(opt, "delete", p->one);
4772                break;
4773        case DIFF_STATUS_ADDED:
4774                show_file_mode_name(opt, "create", p->two);
4775                break;
4776        case DIFF_STATUS_COPIED:
4777                show_rename_copy(opt, "copy", p);
4778                break;
4779        case DIFF_STATUS_RENAMED:
4780                show_rename_copy(opt, "rename", p);
4781                break;
4782        default:
4783                if (p->score) {
4784                        struct strbuf sb = STRBUF_INIT;
4785                        strbuf_addstr(&sb, " rewrite ");
4786                        quote_c_style(p->two->path, &sb, NULL, 0);
4787                        strbuf_addf(&sb, " (%d%%)\n", similarity_index(p));
4788                        emit_diff_symbol(opt, DIFF_SYMBOL_SUMMARY,
4789                                         sb.buf, sb.len, 0);
4790                }
4791                show_mode_change(opt, p, !p->score);
4792                break;
4793        }
4794}
4795
4796struct patch_id_t {
4797        git_SHA_CTX *ctx;
4798        int patchlen;
4799};
4800
4801static int remove_space(char *line, int len)
4802{
4803        int i;
4804        char *dst = line;
4805        unsigned char c;
4806
4807        for (i = 0; i < len; i++)
4808                if (!isspace((c = line[i])))
4809                        *dst++ = c;
4810
4811        return dst - line;
4812}
4813
4814static void patch_id_consume(void *priv, char *line, unsigned long len)
4815{
4816        struct patch_id_t *data = priv;
4817        int new_len;
4818
4819        /* Ignore line numbers when computing the SHA1 of the patch */
4820        if (starts_with(line, "@@ -"))
4821                return;
4822
4823        new_len = remove_space(line, len);
4824
4825        git_SHA1_Update(data->ctx, line, new_len);
4826        data->patchlen += new_len;
4827}
4828
4829static void patch_id_add_string(git_SHA_CTX *ctx, const char *str)
4830{
4831        git_SHA1_Update(ctx, str, strlen(str));
4832}
4833
4834static void patch_id_add_mode(git_SHA_CTX *ctx, unsigned mode)
4835{
4836        /* large enough for 2^32 in octal */
4837        char buf[12];
4838        int len = xsnprintf(buf, sizeof(buf), "%06o", mode);
4839        git_SHA1_Update(ctx, buf, len);
4840}
4841
4842/* returns 0 upon success, and writes result into sha1 */
4843static int diff_get_patch_id(struct diff_options *options, struct object_id *oid, int diff_header_only)
4844{
4845        struct diff_queue_struct *q = &diff_queued_diff;
4846        int i;
4847        git_SHA_CTX ctx;
4848        struct patch_id_t data;
4849
4850        git_SHA1_Init(&ctx);
4851        memset(&data, 0, sizeof(struct patch_id_t));
4852        data.ctx = &ctx;
4853
4854        for (i = 0; i < q->nr; i++) {
4855                xpparam_t xpp;
4856                xdemitconf_t xecfg;
4857                mmfile_t mf1, mf2;
4858                struct diff_filepair *p = q->queue[i];
4859                int len1, len2;
4860
4861                memset(&xpp, 0, sizeof(xpp));
4862                memset(&xecfg, 0, sizeof(xecfg));
4863                if (p->status == 0)
4864                        return error("internal diff status error");
4865                if (p->status == DIFF_STATUS_UNKNOWN)
4866                        continue;
4867                if (diff_unmodified_pair(p))
4868                        continue;
4869                if ((DIFF_FILE_VALID(p->one) && S_ISDIR(p->one->mode)) ||
4870                    (DIFF_FILE_VALID(p->two) && S_ISDIR(p->two->mode)))
4871                        continue;
4872                if (DIFF_PAIR_UNMERGED(p))
4873                        continue;
4874
4875                diff_fill_oid_info(p->one);
4876                diff_fill_oid_info(p->two);
4877
4878                len1 = remove_space(p->one->path, strlen(p->one->path));
4879                len2 = remove_space(p->two->path, strlen(p->two->path));
4880                patch_id_add_string(&ctx, "diff--git");
4881                patch_id_add_string(&ctx, "a/");
4882                git_SHA1_Update(&ctx, p->one->path, len1);
4883                patch_id_add_string(&ctx, "b/");
4884                git_SHA1_Update(&ctx, p->two->path, len2);
4885
4886                if (p->one->mode == 0) {
4887                        patch_id_add_string(&ctx, "newfilemode");
4888                        patch_id_add_mode(&ctx, p->two->mode);
4889                        patch_id_add_string(&ctx, "---/dev/null");
4890                        patch_id_add_string(&ctx, "+++b/");
4891                        git_SHA1_Update(&ctx, p->two->path, len2);
4892                } else if (p->two->mode == 0) {
4893                        patch_id_add_string(&ctx, "deletedfilemode");
4894                        patch_id_add_mode(&ctx, p->one->mode);
4895                        patch_id_add_string(&ctx, "---a/");
4896                        git_SHA1_Update(&ctx, p->one->path, len1);
4897                        patch_id_add_string(&ctx, "+++/dev/null");
4898                } else {
4899                        patch_id_add_string(&ctx, "---a/");
4900                        git_SHA1_Update(&ctx, p->one->path, len1);
4901                        patch_id_add_string(&ctx, "+++b/");
4902                        git_SHA1_Update(&ctx, p->two->path, len2);
4903                }
4904
4905                if (diff_header_only)
4906                        continue;
4907
4908                if (fill_mmfile(&mf1, p->one) < 0 ||
4909                    fill_mmfile(&mf2, p->two) < 0)
4910                        return error("unable to read files to diff");
4911
4912                if (diff_filespec_is_binary(p->one) ||
4913                    diff_filespec_is_binary(p->two)) {
4914                        git_SHA1_Update(&ctx, oid_to_hex(&p->one->oid),
4915                                        GIT_SHA1_HEXSZ);
4916                        git_SHA1_Update(&ctx, oid_to_hex(&p->two->oid),
4917                                        GIT_SHA1_HEXSZ);
4918                        continue;
4919                }
4920
4921                xpp.flags = 0;
4922                xecfg.ctxlen = 3;
4923                xecfg.flags = 0;
4924                if (xdi_diff_outf(&mf1, &mf2, patch_id_consume, &data,
4925                                  &xpp, &xecfg))
4926                        return error("unable to generate patch-id diff for %s",
4927                                     p->one->path);
4928        }
4929
4930        git_SHA1_Final(oid->hash, &ctx);
4931        return 0;
4932}
4933
4934int diff_flush_patch_id(struct diff_options *options, struct object_id *oid, int diff_header_only)
4935{
4936        struct diff_queue_struct *q = &diff_queued_diff;
4937        int i;
4938        int result = diff_get_patch_id(options, oid, diff_header_only);
4939
4940        for (i = 0; i < q->nr; i++)
4941                diff_free_filepair(q->queue[i]);
4942
4943        free(q->queue);
4944        DIFF_QUEUE_CLEAR(q);
4945
4946        return result;
4947}
4948
4949static int is_summary_empty(const struct diff_queue_struct *q)
4950{
4951        int i;
4952
4953        for (i = 0; i < q->nr; i++) {
4954                const struct diff_filepair *p = q->queue[i];
4955
4956                switch (p->status) {
4957                case DIFF_STATUS_DELETED:
4958                case DIFF_STATUS_ADDED:
4959                case DIFF_STATUS_COPIED:
4960                case DIFF_STATUS_RENAMED:
4961                        return 0;
4962                default:
4963                        if (p->score)
4964                                return 0;
4965                        if (p->one->mode && p->two->mode &&
4966                            p->one->mode != p->two->mode)
4967                                return 0;
4968                        break;
4969                }
4970        }
4971        return 1;
4972}
4973
4974static const char rename_limit_warning[] =
4975N_("inexact rename detection was skipped due to too many files.");
4976
4977static const char degrade_cc_to_c_warning[] =
4978N_("only found copies from modified paths due to too many files.");
4979
4980static const char rename_limit_advice[] =
4981N_("you may want to set your %s variable to at least "
4982   "%d and retry the command.");
4983
4984void diff_warn_rename_limit(const char *varname, int needed, int degraded_cc)
4985{
4986        if (degraded_cc)
4987                warning(_(degrade_cc_to_c_warning));
4988        else if (needed)
4989                warning(_(rename_limit_warning));
4990        else
4991                return;
4992        if (0 < needed && needed < 32767)
4993                warning(_(rename_limit_advice), varname, needed);
4994}
4995
4996static void diff_flush_patch_all_file_pairs(struct diff_options *o)
4997{
4998        int i;
4999        struct diff_queue_struct *q = &diff_queued_diff;
5000
5001        if (WSEH_NEW & WS_RULE_MASK)
5002                die("BUG: WS rules bit mask overlaps with diff symbol flags");
5003
5004        for (i = 0; i < q->nr; i++) {
5005                struct diff_filepair *p = q->queue[i];
5006                if (check_pair_status(p))
5007                        diff_flush_patch(p, o);
5008        }
5009}
5010
5011void diff_flush(struct diff_options *options)
5012{
5013        struct diff_queue_struct *q = &diff_queued_diff;
5014        int i, output_format = options->output_format;
5015        int separator = 0;
5016        int dirstat_by_line = 0;
5017
5018        /*
5019         * Order: raw, stat, summary, patch
5020         * or:    name/name-status/checkdiff (other bits clear)
5021         */
5022        if (!q->nr)
5023                goto free_queue;
5024
5025        if (output_format & (DIFF_FORMAT_RAW |
5026                             DIFF_FORMAT_NAME |
5027                             DIFF_FORMAT_NAME_STATUS |
5028                             DIFF_FORMAT_CHECKDIFF)) {
5029                for (i = 0; i < q->nr; i++) {
5030                        struct diff_filepair *p = q->queue[i];
5031                        if (check_pair_status(p))
5032                                flush_one_pair(p, options);
5033                }
5034                separator++;
5035        }
5036
5037        if (output_format & DIFF_FORMAT_DIRSTAT && DIFF_OPT_TST(options, DIRSTAT_BY_LINE))
5038                dirstat_by_line = 1;
5039
5040        if (output_format & (DIFF_FORMAT_DIFFSTAT|DIFF_FORMAT_SHORTSTAT|DIFF_FORMAT_NUMSTAT) ||
5041            dirstat_by_line) {
5042                struct diffstat_t diffstat;
5043
5044                memset(&diffstat, 0, sizeof(struct diffstat_t));
5045                for (i = 0; i < q->nr; i++) {
5046                        struct diff_filepair *p = q->queue[i];
5047                        if (check_pair_status(p))
5048                                diff_flush_stat(p, options, &diffstat);
5049                }
5050                if (output_format & DIFF_FORMAT_NUMSTAT)
5051                        show_numstat(&diffstat, options);
5052                if (output_format & DIFF_FORMAT_DIFFSTAT)
5053                        show_stats(&diffstat, options);
5054                if (output_format & DIFF_FORMAT_SHORTSTAT)
5055                        show_shortstats(&diffstat, options);
5056                if (output_format & DIFF_FORMAT_DIRSTAT && dirstat_by_line)
5057                        show_dirstat_by_line(&diffstat, options);
5058                free_diffstat_info(&diffstat);
5059                separator++;
5060        }
5061        if ((output_format & DIFF_FORMAT_DIRSTAT) && !dirstat_by_line)
5062                show_dirstat(options);
5063
5064        if (output_format & DIFF_FORMAT_SUMMARY && !is_summary_empty(q)) {
5065                for (i = 0; i < q->nr; i++) {
5066                        diff_summary(options, q->queue[i]);
5067                }
5068                separator++;
5069        }
5070
5071        if (output_format & DIFF_FORMAT_NO_OUTPUT &&
5072            DIFF_OPT_TST(options, EXIT_WITH_STATUS) &&
5073            DIFF_OPT_TST(options, DIFF_FROM_CONTENTS)) {
5074                /*
5075                 * run diff_flush_patch for the exit status. setting
5076                 * options->file to /dev/null should be safe, because we
5077                 * aren't supposed to produce any output anyway.
5078                 */
5079                if (options->close_file)
5080                        fclose(options->file);
5081                options->file = xfopen("/dev/null", "w");
5082                options->close_file = 1;
5083                for (i = 0; i < q->nr; i++) {
5084                        struct diff_filepair *p = q->queue[i];
5085                        if (check_pair_status(p))
5086                                diff_flush_patch(p, options);
5087                        if (options->found_changes)
5088                                break;
5089                }
5090        }
5091
5092        if (output_format & DIFF_FORMAT_PATCH) {
5093                if (separator) {
5094                        emit_diff_symbol(options, DIFF_SYMBOL_SEPARATOR, NULL, 0, 0);
5095                        if (options->stat_sep)
5096                                /* attach patch instead of inline */
5097                                emit_diff_symbol(options, DIFF_SYMBOL_STAT_SEP,
5098                                                 NULL, 0, 0);
5099                }
5100
5101                diff_flush_patch_all_file_pairs(options);
5102        }
5103
5104        if (output_format & DIFF_FORMAT_CALLBACK)
5105                options->format_callback(q, options, options->format_callback_data);
5106
5107        for (i = 0; i < q->nr; i++)
5108                diff_free_filepair(q->queue[i]);
5109free_queue:
5110        free(q->queue);
5111        DIFF_QUEUE_CLEAR(q);
5112        if (options->close_file)
5113                fclose(options->file);
5114
5115        /*
5116         * Report the content-level differences with HAS_CHANGES;
5117         * diff_addremove/diff_change does not set the bit when
5118         * DIFF_FROM_CONTENTS is in effect (e.g. with -w).
5119         */
5120        if (DIFF_OPT_TST(options, DIFF_FROM_CONTENTS)) {
5121                if (options->found_changes)
5122                        DIFF_OPT_SET(options, HAS_CHANGES);
5123                else
5124                        DIFF_OPT_CLR(options, HAS_CHANGES);
5125        }
5126}
5127
5128static int match_filter(const struct diff_options *options, const struct diff_filepair *p)
5129{
5130        return (((p->status == DIFF_STATUS_MODIFIED) &&
5131                 ((p->score &&
5132                   filter_bit_tst(DIFF_STATUS_FILTER_BROKEN, options)) ||
5133                  (!p->score &&
5134                   filter_bit_tst(DIFF_STATUS_MODIFIED, options)))) ||
5135                ((p->status != DIFF_STATUS_MODIFIED) &&
5136                 filter_bit_tst(p->status, options)));
5137}
5138
5139static void diffcore_apply_filter(struct diff_options *options)
5140{
5141        int i;
5142        struct diff_queue_struct *q = &diff_queued_diff;
5143        struct diff_queue_struct outq;
5144
5145        DIFF_QUEUE_CLEAR(&outq);
5146
5147        if (!options->filter)
5148                return;
5149
5150        if (filter_bit_tst(DIFF_STATUS_FILTER_AON, options)) {
5151                int found;
5152                for (i = found = 0; !found && i < q->nr; i++) {
5153                        if (match_filter(options, q->queue[i]))
5154                                found++;
5155                }
5156                if (found)
5157                        return;
5158
5159                /* otherwise we will clear the whole queue
5160                 * by copying the empty outq at the end of this
5161                 * function, but first clear the current entries
5162                 * in the queue.
5163                 */
5164                for (i = 0; i < q->nr; i++)
5165                        diff_free_filepair(q->queue[i]);
5166        }
5167        else {
5168                /* Only the matching ones */
5169                for (i = 0; i < q->nr; i++) {
5170                        struct diff_filepair *p = q->queue[i];
5171                        if (match_filter(options, p))
5172                                diff_q(&outq, p);
5173                        else
5174                                diff_free_filepair(p);
5175                }
5176        }
5177        free(q->queue);
5178        *q = outq;
5179}
5180
5181/* Check whether two filespecs with the same mode and size are identical */
5182static int diff_filespec_is_identical(struct diff_filespec *one,
5183                                      struct diff_filespec *two)
5184{
5185        if (S_ISGITLINK(one->mode))
5186                return 0;
5187        if (diff_populate_filespec(one, 0))
5188                return 0;
5189        if (diff_populate_filespec(two, 0))
5190                return 0;
5191        return !memcmp(one->data, two->data, one->size);
5192}
5193
5194static int diff_filespec_check_stat_unmatch(struct diff_filepair *p)
5195{
5196        if (p->done_skip_stat_unmatch)
5197                return p->skip_stat_unmatch_result;
5198
5199        p->done_skip_stat_unmatch = 1;
5200        p->skip_stat_unmatch_result = 0;
5201        /*
5202         * 1. Entries that come from stat info dirtiness
5203         *    always have both sides (iow, not create/delete),
5204         *    one side of the object name is unknown, with
5205         *    the same mode and size.  Keep the ones that
5206         *    do not match these criteria.  They have real
5207         *    differences.
5208         *
5209         * 2. At this point, the file is known to be modified,
5210         *    with the same mode and size, and the object
5211         *    name of one side is unknown.  Need to inspect
5212         *    the identical contents.
5213         */
5214        if (!DIFF_FILE_VALID(p->one) || /* (1) */
5215            !DIFF_FILE_VALID(p->two) ||
5216            (p->one->oid_valid && p->two->oid_valid) ||
5217            (p->one->mode != p->two->mode) ||
5218            diff_populate_filespec(p->one, CHECK_SIZE_ONLY) ||
5219            diff_populate_filespec(p->two, CHECK_SIZE_ONLY) ||
5220            (p->one->size != p->two->size) ||
5221            !diff_filespec_is_identical(p->one, p->two)) /* (2) */
5222                p->skip_stat_unmatch_result = 1;
5223        return p->skip_stat_unmatch_result;
5224}
5225
5226static void diffcore_skip_stat_unmatch(struct diff_options *diffopt)
5227{
5228        int i;
5229        struct diff_queue_struct *q = &diff_queued_diff;
5230        struct diff_queue_struct outq;
5231        DIFF_QUEUE_CLEAR(&outq);
5232
5233        for (i = 0; i < q->nr; i++) {
5234                struct diff_filepair *p = q->queue[i];
5235
5236                if (diff_filespec_check_stat_unmatch(p))
5237                        diff_q(&outq, p);
5238                else {
5239                        /*
5240                         * The caller can subtract 1 from skip_stat_unmatch
5241                         * to determine how many paths were dirty only
5242                         * due to stat info mismatch.
5243                         */
5244                        if (!DIFF_OPT_TST(diffopt, NO_INDEX))
5245                                diffopt->skip_stat_unmatch++;
5246                        diff_free_filepair(p);
5247                }
5248        }
5249        free(q->queue);
5250        *q = outq;
5251}
5252
5253static int diffnamecmp(const void *a_, const void *b_)
5254{
5255        const struct diff_filepair *a = *((const struct diff_filepair **)a_);
5256        const struct diff_filepair *b = *((const struct diff_filepair **)b_);
5257        const char *name_a, *name_b;
5258
5259        name_a = a->one ? a->one->path : a->two->path;
5260        name_b = b->one ? b->one->path : b->two->path;
5261        return strcmp(name_a, name_b);
5262}
5263
5264void diffcore_fix_diff_index(struct diff_options *options)
5265{
5266        struct diff_queue_struct *q = &diff_queued_diff;
5267        QSORT(q->queue, q->nr, diffnamecmp);
5268}
5269
5270void diffcore_std(struct diff_options *options)
5271{
5272        /* NOTE please keep the following in sync with diff_tree_combined() */
5273        if (options->skip_stat_unmatch)
5274                diffcore_skip_stat_unmatch(options);
5275        if (!options->found_follow) {
5276                /* See try_to_follow_renames() in tree-diff.c */
5277                if (options->break_opt != -1)
5278                        diffcore_break(options->break_opt);
5279                if (options->detect_rename)
5280                        diffcore_rename(options);
5281                if (options->break_opt != -1)
5282                        diffcore_merge_broken();
5283        }
5284        if (options->pickaxe)
5285                diffcore_pickaxe(options);
5286        if (options->orderfile)
5287                diffcore_order(options->orderfile);
5288        if (!options->found_follow)
5289                /* See try_to_follow_renames() in tree-diff.c */
5290                diff_resolve_rename_copy();
5291        diffcore_apply_filter(options);
5292
5293        if (diff_queued_diff.nr && !DIFF_OPT_TST(options, DIFF_FROM_CONTENTS))
5294                DIFF_OPT_SET(options, HAS_CHANGES);
5295        else
5296                DIFF_OPT_CLR(options, HAS_CHANGES);
5297
5298        options->found_follow = 0;
5299}
5300
5301int diff_result_code(struct diff_options *opt, int status)
5302{
5303        int result = 0;
5304
5305        diff_warn_rename_limit("diff.renameLimit",
5306                               opt->needed_rename_limit,
5307                               opt->degraded_cc_to_c);
5308        if (!DIFF_OPT_TST(opt, EXIT_WITH_STATUS) &&
5309            !(opt->output_format & DIFF_FORMAT_CHECKDIFF))
5310                return status;
5311        if (DIFF_OPT_TST(opt, EXIT_WITH_STATUS) &&
5312            DIFF_OPT_TST(opt, HAS_CHANGES))
5313                result |= 01;
5314        if ((opt->output_format & DIFF_FORMAT_CHECKDIFF) &&
5315            DIFF_OPT_TST(opt, CHECK_FAILED))
5316                result |= 02;
5317        return result;
5318}
5319
5320int diff_can_quit_early(struct diff_options *opt)
5321{
5322        return (DIFF_OPT_TST(opt, QUICK) &&
5323                !opt->filter &&
5324                DIFF_OPT_TST(opt, HAS_CHANGES));
5325}
5326
5327/*
5328 * Shall changes to this submodule be ignored?
5329 *
5330 * Submodule changes can be configured to be ignored separately for each path,
5331 * but that configuration can be overridden from the command line.
5332 */
5333static int is_submodule_ignored(const char *path, struct diff_options *options)
5334{
5335        int ignored = 0;
5336        unsigned orig_flags = options->flags;
5337        if (!DIFF_OPT_TST(options, OVERRIDE_SUBMODULE_CONFIG))
5338                set_diffopt_flags_from_submodule_config(options, path);
5339        if (DIFF_OPT_TST(options, IGNORE_SUBMODULES))
5340                ignored = 1;
5341        options->flags = orig_flags;
5342        return ignored;
5343}
5344
5345void diff_addremove(struct diff_options *options,
5346                    int addremove, unsigned mode,
5347                    const struct object_id *oid,
5348                    int oid_valid,
5349                    const char *concatpath, unsigned dirty_submodule)
5350{
5351        struct diff_filespec *one, *two;
5352
5353        if (S_ISGITLINK(mode) && is_submodule_ignored(concatpath, options))
5354                return;
5355
5356        /* This may look odd, but it is a preparation for
5357         * feeding "there are unchanged files which should
5358         * not produce diffs, but when you are doing copy
5359         * detection you would need them, so here they are"
5360         * entries to the diff-core.  They will be prefixed
5361         * with something like '=' or '*' (I haven't decided
5362         * which but should not make any difference).
5363         * Feeding the same new and old to diff_change()
5364         * also has the same effect.
5365         * Before the final output happens, they are pruned after
5366         * merged into rename/copy pairs as appropriate.
5367         */
5368        if (DIFF_OPT_TST(options, REVERSE_DIFF))
5369                addremove = (addremove == '+' ? '-' :
5370                             addremove == '-' ? '+' : addremove);
5371
5372        if (options->prefix &&
5373            strncmp(concatpath, options->prefix, options->prefix_length))
5374                return;
5375
5376        one = alloc_filespec(concatpath);
5377        two = alloc_filespec(concatpath);
5378
5379        if (addremove != '+')
5380                fill_filespec(one, oid, oid_valid, mode);
5381        if (addremove != '-') {
5382                fill_filespec(two, oid, oid_valid, mode);
5383                two->dirty_submodule = dirty_submodule;
5384        }
5385
5386        diff_queue(&diff_queued_diff, one, two);
5387        if (!DIFF_OPT_TST(options, DIFF_FROM_CONTENTS))
5388                DIFF_OPT_SET(options, HAS_CHANGES);
5389}
5390
5391void diff_change(struct diff_options *options,
5392                 unsigned old_mode, unsigned new_mode,
5393                 const struct object_id *old_oid,
5394                 const struct object_id *new_oid,
5395                 int old_oid_valid, int new_oid_valid,
5396                 const char *concatpath,
5397                 unsigned old_dirty_submodule, unsigned new_dirty_submodule)
5398{
5399        struct diff_filespec *one, *two;
5400        struct diff_filepair *p;
5401
5402        if (S_ISGITLINK(old_mode) && S_ISGITLINK(new_mode) &&
5403            is_submodule_ignored(concatpath, options))
5404                return;
5405
5406        if (DIFF_OPT_TST(options, REVERSE_DIFF)) {
5407                SWAP(old_mode, new_mode);
5408                SWAP(old_oid, new_oid);
5409                SWAP(old_oid_valid, new_oid_valid);
5410                SWAP(old_dirty_submodule, new_dirty_submodule);
5411        }
5412
5413        if (options->prefix &&
5414            strncmp(concatpath, options->prefix, options->prefix_length))
5415                return;
5416
5417        one = alloc_filespec(concatpath);
5418        two = alloc_filespec(concatpath);
5419        fill_filespec(one, old_oid, old_oid_valid, old_mode);
5420        fill_filespec(two, new_oid, new_oid_valid, new_mode);
5421        one->dirty_submodule = old_dirty_submodule;
5422        two->dirty_submodule = new_dirty_submodule;
5423        p = diff_queue(&diff_queued_diff, one, two);
5424
5425        if (DIFF_OPT_TST(options, DIFF_FROM_CONTENTS))
5426                return;
5427
5428        if (DIFF_OPT_TST(options, QUICK) && options->skip_stat_unmatch &&
5429            !diff_filespec_check_stat_unmatch(p))
5430                return;
5431
5432        DIFF_OPT_SET(options, HAS_CHANGES);
5433}
5434
5435struct diff_filepair *diff_unmerge(struct diff_options *options, const char *path)
5436{
5437        struct diff_filepair *pair;
5438        struct diff_filespec *one, *two;
5439
5440        if (options->prefix &&
5441            strncmp(path, options->prefix, options->prefix_length))
5442                return NULL;
5443
5444        one = alloc_filespec(path);
5445        two = alloc_filespec(path);
5446        pair = diff_queue(&diff_queued_diff, one, two);
5447        pair->is_unmerged = 1;
5448        return pair;
5449}
5450
5451static char *run_textconv(const char *pgm, struct diff_filespec *spec,
5452                size_t *outsize)
5453{
5454        struct diff_tempfile *temp;
5455        const char *argv[3];
5456        const char **arg = argv;
5457        struct child_process child = CHILD_PROCESS_INIT;
5458        struct strbuf buf = STRBUF_INIT;
5459        int err = 0;
5460
5461        temp = prepare_temp_file(spec->path, spec);
5462        *arg++ = pgm;
5463        *arg++ = temp->name;
5464        *arg = NULL;
5465
5466        child.use_shell = 1;
5467        child.argv = argv;
5468        child.out = -1;
5469        if (start_command(&child)) {
5470                remove_tempfile();
5471                return NULL;
5472        }
5473
5474        if (strbuf_read(&buf, child.out, 0) < 0)
5475                err = error("error reading from textconv command '%s'", pgm);
5476        close(child.out);
5477
5478        if (finish_command(&child) || err) {
5479                strbuf_release(&buf);
5480                remove_tempfile();
5481                return NULL;
5482        }
5483        remove_tempfile();
5484
5485        return strbuf_detach(&buf, outsize);
5486}
5487
5488size_t fill_textconv(struct userdiff_driver *driver,
5489                     struct diff_filespec *df,
5490                     char **outbuf)
5491{
5492        size_t size;
5493
5494        if (!driver) {
5495                if (!DIFF_FILE_VALID(df)) {
5496                        *outbuf = "";
5497                        return 0;
5498                }
5499                if (diff_populate_filespec(df, 0))
5500                        die("unable to read files to diff");
5501                *outbuf = df->data;
5502                return df->size;
5503        }
5504
5505        if (!driver->textconv)
5506                die("BUG: fill_textconv called with non-textconv driver");
5507
5508        if (driver->textconv_cache && df->oid_valid) {
5509                *outbuf = notes_cache_get(driver->textconv_cache,
5510                                          &df->oid,
5511                                          &size);
5512                if (*outbuf)
5513                        return size;
5514        }
5515
5516        *outbuf = run_textconv(driver->textconv, df, &size);
5517        if (!*outbuf)
5518                die("unable to read files to diff");
5519
5520        if (driver->textconv_cache && df->oid_valid) {
5521                /* ignore errors, as we might be in a readonly repository */
5522                notes_cache_put(driver->textconv_cache, &df->oid, *outbuf,
5523                                size);
5524                /*
5525                 * we could save up changes and flush them all at the end,
5526                 * but we would need an extra call after all diffing is done.
5527                 * Since generating a cache entry is the slow path anyway,
5528                 * this extra overhead probably isn't a big deal.
5529                 */
5530                notes_cache_write(driver->textconv_cache);
5531        }
5532
5533        return size;
5534}
5535
5536int textconv_object(const char *path,
5537                    unsigned mode,
5538                    const struct object_id *oid,
5539                    int oid_valid,
5540                    char **buf,
5541                    unsigned long *buf_size)
5542{
5543        struct diff_filespec *df;
5544        struct userdiff_driver *textconv;
5545
5546        df = alloc_filespec(path);
5547        fill_filespec(df, oid, oid_valid, mode);
5548        textconv = get_textconv(df);
5549        if (!textconv) {
5550                free_filespec(df);
5551                return 0;
5552        }
5553
5554        *buf_size = fill_textconv(textconv, df, buf);
5555        free_filespec(df);
5556        return 1;
5557}
5558
5559void setup_diff_pager(struct diff_options *opt)
5560{
5561        /*
5562         * If the user asked for our exit code, then either they want --quiet
5563         * or --exit-code. We should definitely not bother with a pager in the
5564         * former case, as we will generate no output. Since we still properly
5565         * report our exit code even when a pager is run, we _could_ run a
5566         * pager with --exit-code. But since we have not done so historically,
5567         * and because it is easy to find people oneline advising "git diff
5568         * --exit-code" in hooks and other scripts, we do not do so.
5569         */
5570        if (!DIFF_OPT_TST(opt, EXIT_WITH_STATUS) &&
5571            check_pager_config("diff") != 0)
5572                setup_pager();
5573}