diff.con commit rev-parse: document --is-inside-git-dir (4faac24)
   1/*
   2 * Copyright (C) 2005 Junio C Hamano
   3 */
   4#include "cache.h"
   5#include "quote.h"
   6#include "diff.h"
   7#include "diffcore.h"
   8#include "delta.h"
   9#include "xdiff-interface.h"
  10#include "color.h"
  11#include "attr.h"
  12
  13#ifdef NO_FAST_WORKING_DIRECTORY
  14#define FAST_WORKING_DIRECTORY 0
  15#else
  16#define FAST_WORKING_DIRECTORY 1
  17#endif
  18
  19static int diff_detect_rename_default;
  20static int diff_rename_limit_default = -1;
  21static int diff_use_color_default;
  22
  23static char diff_colors[][COLOR_MAXLEN] = {
  24        "\033[m",       /* reset */
  25        "",             /* PLAIN (normal) */
  26        "\033[1m",      /* METAINFO (bold) */
  27        "\033[36m",     /* FRAGINFO (cyan) */
  28        "\033[31m",     /* OLD (red) */
  29        "\033[32m",     /* NEW (green) */
  30        "\033[33m",     /* COMMIT (yellow) */
  31        "\033[41m",     /* WHITESPACE (red background) */
  32};
  33
  34static int parse_diff_color_slot(const char *var, int ofs)
  35{
  36        if (!strcasecmp(var+ofs, "plain"))
  37                return DIFF_PLAIN;
  38        if (!strcasecmp(var+ofs, "meta"))
  39                return DIFF_METAINFO;
  40        if (!strcasecmp(var+ofs, "frag"))
  41                return DIFF_FRAGINFO;
  42        if (!strcasecmp(var+ofs, "old"))
  43                return DIFF_FILE_OLD;
  44        if (!strcasecmp(var+ofs, "new"))
  45                return DIFF_FILE_NEW;
  46        if (!strcasecmp(var+ofs, "commit"))
  47                return DIFF_COMMIT;
  48        if (!strcasecmp(var+ofs, "whitespace"))
  49                return DIFF_WHITESPACE;
  50        die("bad config variable '%s'", var);
  51}
  52
  53static struct ll_diff_driver {
  54        const char *name;
  55        struct ll_diff_driver *next;
  56        char *cmd;
  57} *user_diff, **user_diff_tail;
  58
  59/*
  60 * Currently there is only "diff.<drivername>.command" variable;
  61 * because there are "diff.color.<slot>" variables, we are parsing
  62 * this in a bit convoluted way to allow low level diff driver
  63 * called "color".
  64 */
  65static int parse_lldiff_command(const char *var, const char *ep, const char *value)
  66{
  67        const char *name;
  68        int namelen;
  69        struct ll_diff_driver *drv;
  70
  71        name = var + 5;
  72        namelen = ep - name;
  73        for (drv = user_diff; drv; drv = drv->next)
  74                if (!strncmp(drv->name, name, namelen) && !drv->name[namelen])
  75                        break;
  76        if (!drv) {
  77                char *namebuf;
  78                drv = xcalloc(1, sizeof(struct ll_diff_driver));
  79                namebuf = xmalloc(namelen + 1);
  80                memcpy(namebuf, name, namelen);
  81                namebuf[namelen] = 0;
  82                drv->name = namebuf;
  83                drv->next = NULL;
  84                if (!user_diff_tail)
  85                        user_diff_tail = &user_diff;
  86                *user_diff_tail = drv;
  87                user_diff_tail = &(drv->next);
  88        }
  89
  90        if (!value)
  91                return error("%s: lacks value", var);
  92        drv->cmd = strdup(value);
  93        return 0;
  94}
  95
  96/*
  97 * These are to give UI layer defaults.
  98 * The core-level commands such as git-diff-files should
  99 * never be affected by the setting of diff.renames
 100 * the user happens to have in the configuration file.
 101 */
 102int git_diff_ui_config(const char *var, const char *value)
 103{
 104        if (!strcmp(var, "diff.renamelimit")) {
 105                diff_rename_limit_default = git_config_int(var, value);
 106                return 0;
 107        }
 108        if (!strcmp(var, "diff.color") || !strcmp(var, "color.diff")) {
 109                diff_use_color_default = git_config_colorbool(var, value);
 110                return 0;
 111        }
 112        if (!strcmp(var, "diff.renames")) {
 113                if (!value)
 114                        diff_detect_rename_default = DIFF_DETECT_RENAME;
 115                else if (!strcasecmp(value, "copies") ||
 116                         !strcasecmp(value, "copy"))
 117                        diff_detect_rename_default = DIFF_DETECT_COPY;
 118                else if (git_config_bool(var,value))
 119                        diff_detect_rename_default = DIFF_DETECT_RENAME;
 120                return 0;
 121        }
 122        if (!prefixcmp(var, "diff.")) {
 123                const char *ep = strrchr(var, '.');
 124
 125                if (ep != var + 4 && !strcmp(ep, ".command"))
 126                        return parse_lldiff_command(var, ep, value);
 127        }
 128        if (!prefixcmp(var, "diff.color.") || !prefixcmp(var, "color.diff.")) {
 129                int slot = parse_diff_color_slot(var, 11);
 130                color_parse(value, var, diff_colors[slot]);
 131                return 0;
 132        }
 133
 134        return git_default_config(var, value);
 135}
 136
 137static char *quote_one(const char *str)
 138{
 139        int needlen;
 140        char *xp;
 141
 142        if (!str)
 143                return NULL;
 144        needlen = quote_c_style(str, NULL, NULL, 0);
 145        if (!needlen)
 146                return xstrdup(str);
 147        xp = xmalloc(needlen + 1);
 148        quote_c_style(str, xp, NULL, 0);
 149        return xp;
 150}
 151
 152static char *quote_two(const char *one, const char *two)
 153{
 154        int need_one = quote_c_style(one, NULL, NULL, 1);
 155        int need_two = quote_c_style(two, NULL, NULL, 1);
 156        char *xp;
 157
 158        if (need_one + need_two) {
 159                if (!need_one) need_one = strlen(one);
 160                if (!need_two) need_one = strlen(two);
 161
 162                xp = xmalloc(need_one + need_two + 3);
 163                xp[0] = '"';
 164                quote_c_style(one, xp + 1, NULL, 1);
 165                quote_c_style(two, xp + need_one + 1, NULL, 1);
 166                strcpy(xp + need_one + need_two + 1, "\"");
 167                return xp;
 168        }
 169        need_one = strlen(one);
 170        need_two = strlen(two);
 171        xp = xmalloc(need_one + need_two + 1);
 172        strcpy(xp, one);
 173        strcpy(xp + need_one, two);
 174        return xp;
 175}
 176
 177static const char *external_diff(void)
 178{
 179        static const char *external_diff_cmd = NULL;
 180        static int done_preparing = 0;
 181
 182        if (done_preparing)
 183                return external_diff_cmd;
 184        external_diff_cmd = getenv("GIT_EXTERNAL_DIFF");
 185        done_preparing = 1;
 186        return external_diff_cmd;
 187}
 188
 189static struct diff_tempfile {
 190        const char *name; /* filename external diff should read from */
 191        char hex[41];
 192        char mode[10];
 193        char tmp_path[PATH_MAX];
 194} diff_temp[2];
 195
 196static int count_lines(const char *data, int size)
 197{
 198        int count, ch, completely_empty = 1, nl_just_seen = 0;
 199        count = 0;
 200        while (0 < size--) {
 201                ch = *data++;
 202                if (ch == '\n') {
 203                        count++;
 204                        nl_just_seen = 1;
 205                        completely_empty = 0;
 206                }
 207                else {
 208                        nl_just_seen = 0;
 209                        completely_empty = 0;
 210                }
 211        }
 212        if (completely_empty)
 213                return 0;
 214        if (!nl_just_seen)
 215                count++; /* no trailing newline */
 216        return count;
 217}
 218
 219static void print_line_count(int count)
 220{
 221        switch (count) {
 222        case 0:
 223                printf("0,0");
 224                break;
 225        case 1:
 226                printf("1");
 227                break;
 228        default:
 229                printf("1,%d", count);
 230                break;
 231        }
 232}
 233
 234static void copy_file(int prefix, const char *data, int size,
 235                const char *set, const char *reset)
 236{
 237        int ch, nl_just_seen = 1;
 238        while (0 < size--) {
 239                ch = *data++;
 240                if (nl_just_seen) {
 241                        fputs(set, stdout);
 242                        putchar(prefix);
 243                }
 244                if (ch == '\n') {
 245                        nl_just_seen = 1;
 246                        fputs(reset, stdout);
 247                } else
 248                        nl_just_seen = 0;
 249                putchar(ch);
 250        }
 251        if (!nl_just_seen)
 252                printf("%s\n\\ No newline at end of file\n", reset);
 253}
 254
 255static void emit_rewrite_diff(const char *name_a,
 256                              const char *name_b,
 257                              struct diff_filespec *one,
 258                              struct diff_filespec *two,
 259                              int color_diff)
 260{
 261        int lc_a, lc_b;
 262        const char *name_a_tab, *name_b_tab;
 263        const char *metainfo = diff_get_color(color_diff, DIFF_METAINFO);
 264        const char *fraginfo = diff_get_color(color_diff, DIFF_FRAGINFO);
 265        const char *old = diff_get_color(color_diff, DIFF_FILE_OLD);
 266        const char *new = diff_get_color(color_diff, DIFF_FILE_NEW);
 267        const char *reset = diff_get_color(color_diff, DIFF_RESET);
 268
 269        name_a += (*name_a == '/');
 270        name_b += (*name_b == '/');
 271        name_a_tab = strchr(name_a, ' ') ? "\t" : "";
 272        name_b_tab = strchr(name_b, ' ') ? "\t" : "";
 273
 274        diff_populate_filespec(one, 0);
 275        diff_populate_filespec(two, 0);
 276        lc_a = count_lines(one->data, one->size);
 277        lc_b = count_lines(two->data, two->size);
 278        printf("%s--- a/%s%s%s\n%s+++ b/%s%s%s\n%s@@ -",
 279               metainfo, name_a, name_a_tab, reset,
 280               metainfo, name_b, name_b_tab, reset, fraginfo);
 281        print_line_count(lc_a);
 282        printf(" +");
 283        print_line_count(lc_b);
 284        printf(" @@%s\n", reset);
 285        if (lc_a)
 286                copy_file('-', one->data, one->size, old, reset);
 287        if (lc_b)
 288                copy_file('+', two->data, two->size, new, reset);
 289}
 290
 291static int fill_mmfile(mmfile_t *mf, struct diff_filespec *one)
 292{
 293        if (!DIFF_FILE_VALID(one)) {
 294                mf->ptr = (char *)""; /* does not matter */
 295                mf->size = 0;
 296                return 0;
 297        }
 298        else if (diff_populate_filespec(one, 0))
 299                return -1;
 300        mf->ptr = one->data;
 301        mf->size = one->size;
 302        return 0;
 303}
 304
 305struct diff_words_buffer {
 306        mmfile_t text;
 307        long alloc;
 308        long current; /* output pointer */
 309        int suppressed_newline;
 310};
 311
 312static void diff_words_append(char *line, unsigned long len,
 313                struct diff_words_buffer *buffer)
 314{
 315        if (buffer->text.size + len > buffer->alloc) {
 316                buffer->alloc = (buffer->text.size + len) * 3 / 2;
 317                buffer->text.ptr = xrealloc(buffer->text.ptr, buffer->alloc);
 318        }
 319        line++;
 320        len--;
 321        memcpy(buffer->text.ptr + buffer->text.size, line, len);
 322        buffer->text.size += len;
 323}
 324
 325struct diff_words_data {
 326        struct xdiff_emit_state xm;
 327        struct diff_words_buffer minus, plus;
 328};
 329
 330static void print_word(struct diff_words_buffer *buffer, int len, int color,
 331                int suppress_newline)
 332{
 333        const char *ptr;
 334        int eol = 0;
 335
 336        if (len == 0)
 337                return;
 338
 339        ptr  = buffer->text.ptr + buffer->current;
 340        buffer->current += len;
 341
 342        if (ptr[len - 1] == '\n') {
 343                eol = 1;
 344                len--;
 345        }
 346
 347        fputs(diff_get_color(1, color), stdout);
 348        fwrite(ptr, len, 1, stdout);
 349        fputs(diff_get_color(1, DIFF_RESET), stdout);
 350
 351        if (eol) {
 352                if (suppress_newline)
 353                        buffer->suppressed_newline = 1;
 354                else
 355                        putchar('\n');
 356        }
 357}
 358
 359static void fn_out_diff_words_aux(void *priv, char *line, unsigned long len)
 360{
 361        struct diff_words_data *diff_words = priv;
 362
 363        if (diff_words->minus.suppressed_newline) {
 364                if (line[0] != '+')
 365                        putchar('\n');
 366                diff_words->minus.suppressed_newline = 0;
 367        }
 368
 369        len--;
 370        switch (line[0]) {
 371                case '-':
 372                        print_word(&diff_words->minus, len, DIFF_FILE_OLD, 1);
 373                        break;
 374                case '+':
 375                        print_word(&diff_words->plus, len, DIFF_FILE_NEW, 0);
 376                        break;
 377                case ' ':
 378                        print_word(&diff_words->plus, len, DIFF_PLAIN, 0);
 379                        diff_words->minus.current += len;
 380                        break;
 381        }
 382}
 383
 384/* this executes the word diff on the accumulated buffers */
 385static void diff_words_show(struct diff_words_data *diff_words)
 386{
 387        xpparam_t xpp;
 388        xdemitconf_t xecfg;
 389        xdemitcb_t ecb;
 390        mmfile_t minus, plus;
 391        int i;
 392
 393        minus.size = diff_words->minus.text.size;
 394        minus.ptr = xmalloc(minus.size);
 395        memcpy(minus.ptr, diff_words->minus.text.ptr, minus.size);
 396        for (i = 0; i < minus.size; i++)
 397                if (isspace(minus.ptr[i]))
 398                        minus.ptr[i] = '\n';
 399        diff_words->minus.current = 0;
 400
 401        plus.size = diff_words->plus.text.size;
 402        plus.ptr = xmalloc(plus.size);
 403        memcpy(plus.ptr, diff_words->plus.text.ptr, plus.size);
 404        for (i = 0; i < plus.size; i++)
 405                if (isspace(plus.ptr[i]))
 406                        plus.ptr[i] = '\n';
 407        diff_words->plus.current = 0;
 408
 409        xpp.flags = XDF_NEED_MINIMAL;
 410        xecfg.ctxlen = diff_words->minus.alloc + diff_words->plus.alloc;
 411        xecfg.flags = 0;
 412        ecb.outf = xdiff_outf;
 413        ecb.priv = diff_words;
 414        diff_words->xm.consume = fn_out_diff_words_aux;
 415        xdl_diff(&minus, &plus, &xpp, &xecfg, &ecb);
 416
 417        free(minus.ptr);
 418        free(plus.ptr);
 419        diff_words->minus.text.size = diff_words->plus.text.size = 0;
 420
 421        if (diff_words->minus.suppressed_newline) {
 422                putchar('\n');
 423                diff_words->minus.suppressed_newline = 0;
 424        }
 425}
 426
 427struct emit_callback {
 428        struct xdiff_emit_state xm;
 429        int nparents, color_diff;
 430        const char **label_path;
 431        struct diff_words_data *diff_words;
 432        int *found_changesp;
 433};
 434
 435static void free_diff_words_data(struct emit_callback *ecbdata)
 436{
 437        if (ecbdata->diff_words) {
 438                /* flush buffers */
 439                if (ecbdata->diff_words->minus.text.size ||
 440                                ecbdata->diff_words->plus.text.size)
 441                        diff_words_show(ecbdata->diff_words);
 442
 443                if (ecbdata->diff_words->minus.text.ptr)
 444                        free (ecbdata->diff_words->minus.text.ptr);
 445                if (ecbdata->diff_words->plus.text.ptr)
 446                        free (ecbdata->diff_words->plus.text.ptr);
 447                free(ecbdata->diff_words);
 448                ecbdata->diff_words = NULL;
 449        }
 450}
 451
 452const char *diff_get_color(int diff_use_color, enum color_diff ix)
 453{
 454        if (diff_use_color)
 455                return diff_colors[ix];
 456        return "";
 457}
 458
 459static void emit_line(const char *set, const char *reset, const char *line, int len)
 460{
 461        if (len > 0 && line[len-1] == '\n')
 462                len--;
 463        fputs(set, stdout);
 464        fwrite(line, len, 1, stdout);
 465        puts(reset);
 466}
 467
 468static void emit_line_with_ws(int nparents,
 469                const char *set, const char *reset, const char *ws,
 470                const char *line, int len)
 471{
 472        int col0 = nparents;
 473        int last_tab_in_indent = -1;
 474        int last_space_in_indent = -1;
 475        int i;
 476        int tail = len;
 477        int need_highlight_leading_space = 0;
 478        /* The line is a newly added line.  Does it have funny leading
 479         * whitespaces?  In indent, SP should never precede a TAB.
 480         */
 481        for (i = col0; i < len; i++) {
 482                if (line[i] == '\t') {
 483                        last_tab_in_indent = i;
 484                        if (0 <= last_space_in_indent)
 485                                need_highlight_leading_space = 1;
 486                }
 487                else if (line[i] == ' ')
 488                        last_space_in_indent = i;
 489                else
 490                        break;
 491        }
 492        fputs(set, stdout);
 493        fwrite(line, col0, 1, stdout);
 494        fputs(reset, stdout);
 495        if (((i == len) || line[i] == '\n') && i != col0) {
 496                /* The whole line was indent */
 497                emit_line(ws, reset, line + col0, len - col0);
 498                return;
 499        }
 500        i = col0;
 501        if (need_highlight_leading_space) {
 502                while (i < last_tab_in_indent) {
 503                        if (line[i] == ' ') {
 504                                fputs(ws, stdout);
 505                                putchar(' ');
 506                                fputs(reset, stdout);
 507                        }
 508                        else
 509                                putchar(line[i]);
 510                        i++;
 511                }
 512        }
 513        tail = len - 1;
 514        if (line[tail] == '\n' && i < tail)
 515                tail--;
 516        while (i < tail) {
 517                if (!isspace(line[tail]))
 518                        break;
 519                tail--;
 520        }
 521        if ((i < tail && line[tail + 1] != '\n')) {
 522                /* This has whitespace between tail+1..len */
 523                fputs(set, stdout);
 524                fwrite(line + i, tail - i + 1, 1, stdout);
 525                fputs(reset, stdout);
 526                emit_line(ws, reset, line + tail + 1, len - tail - 1);
 527        }
 528        else
 529                emit_line(set, reset, line + i, len - i);
 530}
 531
 532static void emit_add_line(const char *reset, struct emit_callback *ecbdata, const char *line, int len)
 533{
 534        const char *ws = diff_get_color(ecbdata->color_diff, DIFF_WHITESPACE);
 535        const char *set = diff_get_color(ecbdata->color_diff, DIFF_FILE_NEW);
 536
 537        if (!*ws)
 538                emit_line(set, reset, line, len);
 539        else
 540                emit_line_with_ws(ecbdata->nparents, set, reset, ws,
 541                                line, len);
 542}
 543
 544static void fn_out_consume(void *priv, char *line, unsigned long len)
 545{
 546        int i;
 547        int color;
 548        struct emit_callback *ecbdata = priv;
 549        const char *set = diff_get_color(ecbdata->color_diff, DIFF_METAINFO);
 550        const char *reset = diff_get_color(ecbdata->color_diff, DIFF_RESET);
 551
 552        *(ecbdata->found_changesp) = 1;
 553
 554        if (ecbdata->label_path[0]) {
 555                const char *name_a_tab, *name_b_tab;
 556
 557                name_a_tab = strchr(ecbdata->label_path[0], ' ') ? "\t" : "";
 558                name_b_tab = strchr(ecbdata->label_path[1], ' ') ? "\t" : "";
 559
 560                printf("%s--- %s%s%s\n",
 561                       set, ecbdata->label_path[0], reset, name_a_tab);
 562                printf("%s+++ %s%s%s\n",
 563                       set, ecbdata->label_path[1], reset, name_b_tab);
 564                ecbdata->label_path[0] = ecbdata->label_path[1] = NULL;
 565        }
 566
 567        /* This is not really necessary for now because
 568         * this codepath only deals with two-way diffs.
 569         */
 570        for (i = 0; i < len && line[i] == '@'; i++)
 571                ;
 572        if (2 <= i && i < len && line[i] == ' ') {
 573                ecbdata->nparents = i - 1;
 574                emit_line(diff_get_color(ecbdata->color_diff, DIFF_FRAGINFO),
 575                          reset, line, len);
 576                return;
 577        }
 578
 579        if (len < ecbdata->nparents) {
 580                set = reset;
 581                emit_line(reset, reset, line, len);
 582                return;
 583        }
 584
 585        color = DIFF_PLAIN;
 586        if (ecbdata->diff_words && ecbdata->nparents != 1)
 587                /* fall back to normal diff */
 588                free_diff_words_data(ecbdata);
 589        if (ecbdata->diff_words) {
 590                if (line[0] == '-') {
 591                        diff_words_append(line, len,
 592                                          &ecbdata->diff_words->minus);
 593                        return;
 594                } else if (line[0] == '+') {
 595                        diff_words_append(line, len,
 596                                          &ecbdata->diff_words->plus);
 597                        return;
 598                }
 599                if (ecbdata->diff_words->minus.text.size ||
 600                    ecbdata->diff_words->plus.text.size)
 601                        diff_words_show(ecbdata->diff_words);
 602                line++;
 603                len--;
 604                emit_line(set, reset, line, len);
 605                return;
 606        }
 607        for (i = 0; i < ecbdata->nparents && len; i++) {
 608                if (line[i] == '-')
 609                        color = DIFF_FILE_OLD;
 610                else if (line[i] == '+')
 611                        color = DIFF_FILE_NEW;
 612        }
 613
 614        if (color != DIFF_FILE_NEW) {
 615                emit_line(diff_get_color(ecbdata->color_diff, color),
 616                          reset, line, len);
 617                return;
 618        }
 619        emit_add_line(reset, ecbdata, line, len);
 620}
 621
 622static char *pprint_rename(const char *a, const char *b)
 623{
 624        const char *old = a;
 625        const char *new = b;
 626        char *name = NULL;
 627        int pfx_length, sfx_length;
 628        int len_a = strlen(a);
 629        int len_b = strlen(b);
 630        int qlen_a = quote_c_style(a, NULL, NULL, 0);
 631        int qlen_b = quote_c_style(b, NULL, NULL, 0);
 632
 633        if (qlen_a || qlen_b) {
 634                if (qlen_a) len_a = qlen_a;
 635                if (qlen_b) len_b = qlen_b;
 636                name = xmalloc( len_a + len_b + 5 );
 637                if (qlen_a)
 638                        quote_c_style(a, name, NULL, 0);
 639                else
 640                        memcpy(name, a, len_a);
 641                memcpy(name + len_a, " => ", 4);
 642                if (qlen_b)
 643                        quote_c_style(b, name + len_a + 4, NULL, 0);
 644                else
 645                        memcpy(name + len_a + 4, b, len_b + 1);
 646                return name;
 647        }
 648
 649        /* Find common prefix */
 650        pfx_length = 0;
 651        while (*old && *new && *old == *new) {
 652                if (*old == '/')
 653                        pfx_length = old - a + 1;
 654                old++;
 655                new++;
 656        }
 657
 658        /* Find common suffix */
 659        old = a + len_a;
 660        new = b + len_b;
 661        sfx_length = 0;
 662        while (a <= old && b <= new && *old == *new) {
 663                if (*old == '/')
 664                        sfx_length = len_a - (old - a);
 665                old--;
 666                new--;
 667        }
 668
 669        /*
 670         * pfx{mid-a => mid-b}sfx
 671         * {pfx-a => pfx-b}sfx
 672         * pfx{sfx-a => sfx-b}
 673         * name-a => name-b
 674         */
 675        if (pfx_length + sfx_length) {
 676                int a_midlen = len_a - pfx_length - sfx_length;
 677                int b_midlen = len_b - pfx_length - sfx_length;
 678                if (a_midlen < 0) a_midlen = 0;
 679                if (b_midlen < 0) b_midlen = 0;
 680
 681                name = xmalloc(pfx_length + a_midlen + b_midlen + sfx_length + 7);
 682                sprintf(name, "%.*s{%.*s => %.*s}%s",
 683                        pfx_length, a,
 684                        a_midlen, a + pfx_length,
 685                        b_midlen, b + pfx_length,
 686                        a + len_a - sfx_length);
 687        }
 688        else {
 689                name = xmalloc(len_a + len_b + 5);
 690                sprintf(name, "%s => %s", a, b);
 691        }
 692        return name;
 693}
 694
 695struct diffstat_t {
 696        struct xdiff_emit_state xm;
 697
 698        int nr;
 699        int alloc;
 700        struct diffstat_file {
 701                char *name;
 702                unsigned is_unmerged:1;
 703                unsigned is_binary:1;
 704                unsigned is_renamed:1;
 705                unsigned int added, deleted;
 706        } **files;
 707};
 708
 709static struct diffstat_file *diffstat_add(struct diffstat_t *diffstat,
 710                                          const char *name_a,
 711                                          const char *name_b)
 712{
 713        struct diffstat_file *x;
 714        x = xcalloc(sizeof (*x), 1);
 715        if (diffstat->nr == diffstat->alloc) {
 716                diffstat->alloc = alloc_nr(diffstat->alloc);
 717                diffstat->files = xrealloc(diffstat->files,
 718                                diffstat->alloc * sizeof(x));
 719        }
 720        diffstat->files[diffstat->nr++] = x;
 721        if (name_b) {
 722                x->name = pprint_rename(name_a, name_b);
 723                x->is_renamed = 1;
 724        }
 725        else
 726                x->name = xstrdup(name_a);
 727        return x;
 728}
 729
 730static void diffstat_consume(void *priv, char *line, unsigned long len)
 731{
 732        struct diffstat_t *diffstat = priv;
 733        struct diffstat_file *x = diffstat->files[diffstat->nr - 1];
 734
 735        if (line[0] == '+')
 736                x->added++;
 737        else if (line[0] == '-')
 738                x->deleted++;
 739}
 740
 741const char mime_boundary_leader[] = "------------";
 742
 743static int scale_linear(int it, int width, int max_change)
 744{
 745        /*
 746         * make sure that at least one '-' is printed if there were deletions,
 747         * and likewise for '+'.
 748         */
 749        if (max_change < 2)
 750                return it;
 751        return ((it - 1) * (width - 1) + max_change - 1) / (max_change - 1);
 752}
 753
 754static void show_name(const char *prefix, const char *name, int len,
 755                      const char *reset, const char *set)
 756{
 757        printf(" %s%s%-*s%s |", set, prefix, len, name, reset);
 758}
 759
 760static void show_graph(char ch, int cnt, const char *set, const char *reset)
 761{
 762        if (cnt <= 0)
 763                return;
 764        printf("%s", set);
 765        while (cnt--)
 766                putchar(ch);
 767        printf("%s", reset);
 768}
 769
 770static void show_stats(struct diffstat_t* data, struct diff_options *options)
 771{
 772        int i, len, add, del, total, adds = 0, dels = 0;
 773        int max_change = 0, max_len = 0;
 774        int total_files = data->nr;
 775        int width, name_width;
 776        const char *reset, *set, *add_c, *del_c;
 777
 778        if (data->nr == 0)
 779                return;
 780
 781        width = options->stat_width ? options->stat_width : 80;
 782        name_width = options->stat_name_width ? options->stat_name_width : 50;
 783
 784        /* Sanity: give at least 5 columns to the graph,
 785         * but leave at least 10 columns for the name.
 786         */
 787        if (width < name_width + 15) {
 788                if (name_width <= 25)
 789                        width = name_width + 15;
 790                else
 791                        name_width = width - 15;
 792        }
 793
 794        /* Find the longest filename and max number of changes */
 795        reset = diff_get_color(options->color_diff, DIFF_RESET);
 796        set = diff_get_color(options->color_diff, DIFF_PLAIN);
 797        add_c = diff_get_color(options->color_diff, DIFF_FILE_NEW);
 798        del_c = diff_get_color(options->color_diff, DIFF_FILE_OLD);
 799
 800        for (i = 0; i < data->nr; i++) {
 801                struct diffstat_file *file = data->files[i];
 802                int change = file->added + file->deleted;
 803
 804                if (!file->is_renamed) {  /* renames are already quoted by pprint_rename */
 805                        len = quote_c_style(file->name, NULL, NULL, 0);
 806                        if (len) {
 807                                char *qname = xmalloc(len + 1);
 808                                quote_c_style(file->name, qname, NULL, 0);
 809                                free(file->name);
 810                                file->name = qname;
 811                        }
 812                }
 813
 814                len = strlen(file->name);
 815                if (max_len < len)
 816                        max_len = len;
 817
 818                if (file->is_binary || file->is_unmerged)
 819                        continue;
 820                if (max_change < change)
 821                        max_change = change;
 822        }
 823
 824        /* Compute the width of the graph part;
 825         * 10 is for one blank at the beginning of the line plus
 826         * " | count " between the name and the graph.
 827         *
 828         * From here on, name_width is the width of the name area,
 829         * and width is the width of the graph area.
 830         */
 831        name_width = (name_width < max_len) ? name_width : max_len;
 832        if (width < (name_width + 10) + max_change)
 833                width = width - (name_width + 10);
 834        else
 835                width = max_change;
 836
 837        for (i = 0; i < data->nr; i++) {
 838                const char *prefix = "";
 839                char *name = data->files[i]->name;
 840                int added = data->files[i]->added;
 841                int deleted = data->files[i]->deleted;
 842                int name_len;
 843
 844                /*
 845                 * "scale" the filename
 846                 */
 847                len = name_width;
 848                name_len = strlen(name);
 849                if (name_width < name_len) {
 850                        char *slash;
 851                        prefix = "...";
 852                        len -= 3;
 853                        name += name_len - len;
 854                        slash = strchr(name, '/');
 855                        if (slash)
 856                                name = slash;
 857                }
 858
 859                if (data->files[i]->is_binary) {
 860                        show_name(prefix, name, len, reset, set);
 861                        printf("  Bin ");
 862                        printf("%s%d%s", del_c, deleted, reset);
 863                        printf(" -> ");
 864                        printf("%s%d%s", add_c, added, reset);
 865                        printf(" bytes");
 866                        printf("\n");
 867                        goto free_diffstat_file;
 868                }
 869                else if (data->files[i]->is_unmerged) {
 870                        show_name(prefix, name, len, reset, set);
 871                        printf("  Unmerged\n");
 872                        goto free_diffstat_file;
 873                }
 874                else if (!data->files[i]->is_renamed &&
 875                         (added + deleted == 0)) {
 876                        total_files--;
 877                        goto free_diffstat_file;
 878                }
 879
 880                /*
 881                 * scale the add/delete
 882                 */
 883                add = added;
 884                del = deleted;
 885                total = add + del;
 886                adds += add;
 887                dels += del;
 888
 889                if (width <= max_change) {
 890                        add = scale_linear(add, width, max_change);
 891                        del = scale_linear(del, width, max_change);
 892                        total = add + del;
 893                }
 894                show_name(prefix, name, len, reset, set);
 895                printf("%5d ", added + deleted);
 896                show_graph('+', add, add_c, reset);
 897                show_graph('-', del, del_c, reset);
 898                putchar('\n');
 899        free_diffstat_file:
 900                free(data->files[i]->name);
 901                free(data->files[i]);
 902        }
 903        free(data->files);
 904        printf("%s %d files changed, %d insertions(+), %d deletions(-)%s\n",
 905               set, total_files, adds, dels, reset);
 906}
 907
 908static void show_shortstats(struct diffstat_t* data)
 909{
 910        int i, adds = 0, dels = 0, total_files = data->nr;
 911
 912        if (data->nr == 0)
 913                return;
 914
 915        for (i = 0; i < data->nr; i++) {
 916                if (!data->files[i]->is_binary &&
 917                    !data->files[i]->is_unmerged) {
 918                        int added = data->files[i]->added;
 919                        int deleted= data->files[i]->deleted;
 920                        if (!data->files[i]->is_renamed &&
 921                            (added + deleted == 0)) {
 922                                total_files--;
 923                        } else {
 924                                adds += added;
 925                                dels += deleted;
 926                        }
 927                }
 928                free(data->files[i]->name);
 929                free(data->files[i]);
 930        }
 931        free(data->files);
 932
 933        printf(" %d files changed, %d insertions(+), %d deletions(-)\n",
 934               total_files, adds, dels);
 935}
 936
 937static void show_numstat(struct diffstat_t* data, struct diff_options *options)
 938{
 939        int i;
 940
 941        for (i = 0; i < data->nr; i++) {
 942                struct diffstat_file *file = data->files[i];
 943
 944                if (file->is_binary)
 945                        printf("-\t-\t");
 946                else
 947                        printf("%d\t%d\t", file->added, file->deleted);
 948                if (options->line_termination && !file->is_renamed &&
 949                    quote_c_style(file->name, NULL, NULL, 0))
 950                        quote_c_style(file->name, NULL, stdout, 0);
 951                else
 952                        fputs(file->name, stdout);
 953                putchar(options->line_termination);
 954        }
 955}
 956
 957struct checkdiff_t {
 958        struct xdiff_emit_state xm;
 959        const char *filename;
 960        int lineno, color_diff;
 961};
 962
 963static void checkdiff_consume(void *priv, char *line, unsigned long len)
 964{
 965        struct checkdiff_t *data = priv;
 966        const char *ws = diff_get_color(data->color_diff, DIFF_WHITESPACE);
 967        const char *reset = diff_get_color(data->color_diff, DIFF_RESET);
 968        const char *set = diff_get_color(data->color_diff, DIFF_FILE_NEW);
 969
 970        if (line[0] == '+') {
 971                int i, spaces = 0, space_before_tab = 0, white_space_at_end = 0;
 972
 973                /* check space before tab */
 974                for (i = 1; i < len && (line[i] == ' ' || line[i] == '\t'); i++)
 975                        if (line[i] == ' ')
 976                                spaces++;
 977                if (line[i - 1] == '\t' && spaces)
 978                        space_before_tab = 1;
 979
 980                /* check white space at line end */
 981                if (line[len - 1] == '\n')
 982                        len--;
 983                if (isspace(line[len - 1]))
 984                        white_space_at_end = 1;
 985
 986                if (space_before_tab || white_space_at_end) {
 987                        printf("%s:%d: %s", data->filename, data->lineno, ws);
 988                        if (space_before_tab) {
 989                                printf("space before tab");
 990                                if (white_space_at_end)
 991                                        putchar(',');
 992                        }
 993                        if (white_space_at_end)
 994                                printf("white space at end");
 995                        printf(":%s ", reset);
 996                        emit_line_with_ws(1, set, reset, ws, line, len);
 997                }
 998
 999                data->lineno++;
1000        } else if (line[0] == ' ')
1001                data->lineno++;
1002        else if (line[0] == '@') {
1003                char *plus = strchr(line, '+');
1004                if (plus)
1005                        data->lineno = strtol(plus, NULL, 10);
1006                else
1007                        die("invalid diff");
1008        }
1009}
1010
1011static unsigned char *deflate_it(char *data,
1012                                 unsigned long size,
1013                                 unsigned long *result_size)
1014{
1015        int bound;
1016        unsigned char *deflated;
1017        z_stream stream;
1018
1019        memset(&stream, 0, sizeof(stream));
1020        deflateInit(&stream, zlib_compression_level);
1021        bound = deflateBound(&stream, size);
1022        deflated = xmalloc(bound);
1023        stream.next_out = deflated;
1024        stream.avail_out = bound;
1025
1026        stream.next_in = (unsigned char *)data;
1027        stream.avail_in = size;
1028        while (deflate(&stream, Z_FINISH) == Z_OK)
1029                ; /* nothing */
1030        deflateEnd(&stream);
1031        *result_size = stream.total_out;
1032        return deflated;
1033}
1034
1035static void emit_binary_diff_body(mmfile_t *one, mmfile_t *two)
1036{
1037        void *cp;
1038        void *delta;
1039        void *deflated;
1040        void *data;
1041        unsigned long orig_size;
1042        unsigned long delta_size;
1043        unsigned long deflate_size;
1044        unsigned long data_size;
1045
1046        /* We could do deflated delta, or we could do just deflated two,
1047         * whichever is smaller.
1048         */
1049        delta = NULL;
1050        deflated = deflate_it(two->ptr, two->size, &deflate_size);
1051        if (one->size && two->size) {
1052                delta = diff_delta(one->ptr, one->size,
1053                                   two->ptr, two->size,
1054                                   &delta_size, deflate_size);
1055                if (delta) {
1056                        void *to_free = delta;
1057                        orig_size = delta_size;
1058                        delta = deflate_it(delta, delta_size, &delta_size);
1059                        free(to_free);
1060                }
1061        }
1062
1063        if (delta && delta_size < deflate_size) {
1064                printf("delta %lu\n", orig_size);
1065                free(deflated);
1066                data = delta;
1067                data_size = delta_size;
1068        }
1069        else {
1070                printf("literal %lu\n", two->size);
1071                free(delta);
1072                data = deflated;
1073                data_size = deflate_size;
1074        }
1075
1076        /* emit data encoded in base85 */
1077        cp = data;
1078        while (data_size) {
1079                int bytes = (52 < data_size) ? 52 : data_size;
1080                char line[70];
1081                data_size -= bytes;
1082                if (bytes <= 26)
1083                        line[0] = bytes + 'A' - 1;
1084                else
1085                        line[0] = bytes - 26 + 'a' - 1;
1086                encode_85(line + 1, cp, bytes);
1087                cp = (char *) cp + bytes;
1088                puts(line);
1089        }
1090        printf("\n");
1091        free(data);
1092}
1093
1094static void emit_binary_diff(mmfile_t *one, mmfile_t *two)
1095{
1096        printf("GIT binary patch\n");
1097        emit_binary_diff_body(one, two);
1098        emit_binary_diff_body(two, one);
1099}
1100
1101static void setup_diff_attr_check(struct git_attr_check *check)
1102{
1103        static struct git_attr *attr_diff;
1104
1105        if (!attr_diff)
1106                attr_diff = git_attr("diff", 4);
1107        check->attr = attr_diff;
1108}
1109
1110static int file_is_binary(struct diff_filespec *one)
1111{
1112        struct git_attr_check attr_diff_check;
1113
1114        setup_diff_attr_check(&attr_diff_check);
1115        if (!git_checkattr(one->path, 1, &attr_diff_check)) {
1116                const char *value = attr_diff_check.value;
1117                if (ATTR_TRUE(value))
1118                        return 0;
1119                else if (ATTR_FALSE(value))
1120                        return 1;
1121        }
1122
1123        if (!one->data) {
1124                if (!DIFF_FILE_VALID(one))
1125                        return 0;
1126                diff_populate_filespec(one, 0);
1127        }
1128        return buffer_is_binary(one->data, one->size);
1129}
1130
1131static void builtin_diff(const char *name_a,
1132                         const char *name_b,
1133                         struct diff_filespec *one,
1134                         struct diff_filespec *two,
1135                         const char *xfrm_msg,
1136                         struct diff_options *o,
1137                         int complete_rewrite)
1138{
1139        mmfile_t mf1, mf2;
1140        const char *lbl[2];
1141        char *a_one, *b_two;
1142        const char *set = diff_get_color(o->color_diff, DIFF_METAINFO);
1143        const char *reset = diff_get_color(o->color_diff, DIFF_RESET);
1144
1145        a_one = quote_two("a/", name_a + (*name_a == '/'));
1146        b_two = quote_two("b/", name_b + (*name_b == '/'));
1147        lbl[0] = DIFF_FILE_VALID(one) ? a_one : "/dev/null";
1148        lbl[1] = DIFF_FILE_VALID(two) ? b_two : "/dev/null";
1149        printf("%sdiff --git %s %s%s\n", set, a_one, b_two, reset);
1150        if (lbl[0][0] == '/') {
1151                /* /dev/null */
1152                printf("%snew file mode %06o%s\n", set, two->mode, reset);
1153                if (xfrm_msg && xfrm_msg[0])
1154                        printf("%s%s%s\n", set, xfrm_msg, reset);
1155        }
1156        else if (lbl[1][0] == '/') {
1157                printf("%sdeleted file mode %06o%s\n", set, one->mode, reset);
1158                if (xfrm_msg && xfrm_msg[0])
1159                        printf("%s%s%s\n", set, xfrm_msg, reset);
1160        }
1161        else {
1162                if (one->mode != two->mode) {
1163                        printf("%sold mode %06o%s\n", set, one->mode, reset);
1164                        printf("%snew mode %06o%s\n", set, two->mode, reset);
1165                }
1166                if (xfrm_msg && xfrm_msg[0])
1167                        printf("%s%s%s\n", set, xfrm_msg, reset);
1168                /*
1169                 * we do not run diff between different kind
1170                 * of objects.
1171                 */
1172                if ((one->mode ^ two->mode) & S_IFMT)
1173                        goto free_ab_and_return;
1174                if (complete_rewrite) {
1175                        emit_rewrite_diff(name_a, name_b, one, two,
1176                                        o->color_diff);
1177                        o->found_changes = 1;
1178                        goto free_ab_and_return;
1179                }
1180        }
1181
1182        if (fill_mmfile(&mf1, one) < 0 || fill_mmfile(&mf2, two) < 0)
1183                die("unable to read files to diff");
1184
1185        if (!o->text && (file_is_binary(one) || file_is_binary(two))) {
1186                /* Quite common confusing case */
1187                if (mf1.size == mf2.size &&
1188                    !memcmp(mf1.ptr, mf2.ptr, mf1.size))
1189                        goto free_ab_and_return;
1190                if (o->binary)
1191                        emit_binary_diff(&mf1, &mf2);
1192                else
1193                        printf("Binary files %s and %s differ\n",
1194                               lbl[0], lbl[1]);
1195                o->found_changes = 1;
1196        }
1197        else {
1198                /* Crazy xdl interfaces.. */
1199                const char *diffopts = getenv("GIT_DIFF_OPTS");
1200                xpparam_t xpp;
1201                xdemitconf_t xecfg;
1202                xdemitcb_t ecb;
1203                struct emit_callback ecbdata;
1204
1205                memset(&ecbdata, 0, sizeof(ecbdata));
1206                ecbdata.label_path = lbl;
1207                ecbdata.color_diff = o->color_diff;
1208                ecbdata.found_changesp = &o->found_changes;
1209                xpp.flags = XDF_NEED_MINIMAL | o->xdl_opts;
1210                xecfg.ctxlen = o->context;
1211                xecfg.flags = XDL_EMIT_FUNCNAMES;
1212                if (!diffopts)
1213                        ;
1214                else if (!prefixcmp(diffopts, "--unified="))
1215                        xecfg.ctxlen = strtoul(diffopts + 10, NULL, 10);
1216                else if (!prefixcmp(diffopts, "-u"))
1217                        xecfg.ctxlen = strtoul(diffopts + 2, NULL, 10);
1218                ecb.outf = xdiff_outf;
1219                ecb.priv = &ecbdata;
1220                ecbdata.xm.consume = fn_out_consume;
1221                if (o->color_diff_words)
1222                        ecbdata.diff_words =
1223                                xcalloc(1, sizeof(struct diff_words_data));
1224                xdl_diff(&mf1, &mf2, &xpp, &xecfg, &ecb);
1225                if (o->color_diff_words)
1226                        free_diff_words_data(&ecbdata);
1227        }
1228
1229 free_ab_and_return:
1230        diff_free_filespec_data(one);
1231        diff_free_filespec_data(two);
1232        free(a_one);
1233        free(b_two);
1234        return;
1235}
1236
1237static void builtin_diffstat(const char *name_a, const char *name_b,
1238                             struct diff_filespec *one,
1239                             struct diff_filespec *two,
1240                             struct diffstat_t *diffstat,
1241                             struct diff_options *o,
1242                             int complete_rewrite)
1243{
1244        mmfile_t mf1, mf2;
1245        struct diffstat_file *data;
1246
1247        data = diffstat_add(diffstat, name_a, name_b);
1248
1249        if (!one || !two) {
1250                data->is_unmerged = 1;
1251                return;
1252        }
1253        if (complete_rewrite) {
1254                diff_populate_filespec(one, 0);
1255                diff_populate_filespec(two, 0);
1256                data->deleted = count_lines(one->data, one->size);
1257                data->added = count_lines(two->data, two->size);
1258                goto free_and_return;
1259        }
1260        if (fill_mmfile(&mf1, one) < 0 || fill_mmfile(&mf2, two) < 0)
1261                die("unable to read files to diff");
1262
1263        if (file_is_binary(one) || file_is_binary(two)) {
1264                data->is_binary = 1;
1265                data->added = mf2.size;
1266                data->deleted = mf1.size;
1267        } else {
1268                /* Crazy xdl interfaces.. */
1269                xpparam_t xpp;
1270                xdemitconf_t xecfg;
1271                xdemitcb_t ecb;
1272
1273                xpp.flags = XDF_NEED_MINIMAL | o->xdl_opts;
1274                xecfg.ctxlen = 0;
1275                xecfg.flags = 0;
1276                ecb.outf = xdiff_outf;
1277                ecb.priv = diffstat;
1278                xdl_diff(&mf1, &mf2, &xpp, &xecfg, &ecb);
1279        }
1280
1281 free_and_return:
1282        diff_free_filespec_data(one);
1283        diff_free_filespec_data(two);
1284}
1285
1286static void builtin_checkdiff(const char *name_a, const char *name_b,
1287                             struct diff_filespec *one,
1288                             struct diff_filespec *two, struct diff_options *o)
1289{
1290        mmfile_t mf1, mf2;
1291        struct checkdiff_t data;
1292
1293        if (!two)
1294                return;
1295
1296        memset(&data, 0, sizeof(data));
1297        data.xm.consume = checkdiff_consume;
1298        data.filename = name_b ? name_b : name_a;
1299        data.lineno = 0;
1300        data.color_diff = o->color_diff;
1301
1302        if (fill_mmfile(&mf1, one) < 0 || fill_mmfile(&mf2, two) < 0)
1303                die("unable to read files to diff");
1304
1305        if (file_is_binary(two))
1306                goto free_and_return;
1307        else {
1308                /* Crazy xdl interfaces.. */
1309                xpparam_t xpp;
1310                xdemitconf_t xecfg;
1311                xdemitcb_t ecb;
1312
1313                xpp.flags = XDF_NEED_MINIMAL;
1314                xecfg.ctxlen = 0;
1315                xecfg.flags = 0;
1316                ecb.outf = xdiff_outf;
1317                ecb.priv = &data;
1318                xdl_diff(&mf1, &mf2, &xpp, &xecfg, &ecb);
1319        }
1320 free_and_return:
1321        diff_free_filespec_data(one);
1322        diff_free_filespec_data(two);
1323}
1324
1325struct diff_filespec *alloc_filespec(const char *path)
1326{
1327        int namelen = strlen(path);
1328        struct diff_filespec *spec = xmalloc(sizeof(*spec) + namelen + 1);
1329
1330        memset(spec, 0, sizeof(*spec));
1331        spec->path = (char *)(spec + 1);
1332        memcpy(spec->path, path, namelen+1);
1333        return spec;
1334}
1335
1336void fill_filespec(struct diff_filespec *spec, const unsigned char *sha1,
1337                   unsigned short mode)
1338{
1339        if (mode) {
1340                spec->mode = canon_mode(mode);
1341                hashcpy(spec->sha1, sha1);
1342                spec->sha1_valid = !is_null_sha1(sha1);
1343        }
1344}
1345
1346/*
1347 * Given a name and sha1 pair, if the index tells us the file in
1348 * the work tree has that object contents, return true, so that
1349 * prepare_temp_file() does not have to inflate and extract.
1350 */
1351static int reuse_worktree_file(const char *name, const unsigned char *sha1, int want_file)
1352{
1353        struct cache_entry *ce;
1354        struct stat st;
1355        int pos, len;
1356
1357        /* We do not read the cache ourselves here, because the
1358         * benchmark with my previous version that always reads cache
1359         * shows that it makes things worse for diff-tree comparing
1360         * two linux-2.6 kernel trees in an already checked out work
1361         * tree.  This is because most diff-tree comparisons deal with
1362         * only a small number of files, while reading the cache is
1363         * expensive for a large project, and its cost outweighs the
1364         * savings we get by not inflating the object to a temporary
1365         * file.  Practically, this code only helps when we are used
1366         * by diff-cache --cached, which does read the cache before
1367         * calling us.
1368         */
1369        if (!active_cache)
1370                return 0;
1371
1372        /* We want to avoid the working directory if our caller
1373         * doesn't need the data in a normal file, this system
1374         * is rather slow with its stat/open/mmap/close syscalls,
1375         * and the object is contained in a pack file.  The pack
1376         * is probably already open and will be faster to obtain
1377         * the data through than the working directory.  Loose
1378         * objects however would tend to be slower as they need
1379         * to be individually opened and inflated.
1380         */
1381        if (!FAST_WORKING_DIRECTORY && !want_file && has_sha1_pack(sha1, NULL))
1382                return 0;
1383
1384        len = strlen(name);
1385        pos = cache_name_pos(name, len);
1386        if (pos < 0)
1387                return 0;
1388        ce = active_cache[pos];
1389        if ((lstat(name, &st) < 0) ||
1390            !S_ISREG(st.st_mode) || /* careful! */
1391            ce_match_stat(ce, &st, 0) ||
1392            hashcmp(sha1, ce->sha1))
1393                return 0;
1394        /* we return 1 only when we can stat, it is a regular file,
1395         * stat information matches, and sha1 recorded in the cache
1396         * matches.  I.e. we know the file in the work tree really is
1397         * the same as the <name, sha1> pair.
1398         */
1399        return 1;
1400}
1401
1402static int populate_from_stdin(struct diff_filespec *s)
1403{
1404#define INCREMENT 1024
1405        char *buf;
1406        unsigned long size;
1407        ssize_t got;
1408
1409        size = 0;
1410        buf = NULL;
1411        while (1) {
1412                buf = xrealloc(buf, size + INCREMENT);
1413                got = xread(0, buf + size, INCREMENT);
1414                if (!got)
1415                        break; /* EOF */
1416                if (got < 0)
1417                        return error("error while reading from stdin %s",
1418                                     strerror(errno));
1419                size += got;
1420        }
1421        s->should_munmap = 0;
1422        s->data = buf;
1423        s->size = size;
1424        s->should_free = 1;
1425        return 0;
1426}
1427
1428static int diff_populate_gitlink(struct diff_filespec *s, int size_only)
1429{
1430        int len;
1431        char *data = xmalloc(100);
1432        len = snprintf(data, 100,
1433                "Subproject commit %s\n", sha1_to_hex(s->sha1));
1434        s->data = data;
1435        s->size = len;
1436        s->should_free = 1;
1437        if (size_only) {
1438                s->data = NULL;
1439                free(data);
1440        }
1441        return 0;
1442}
1443
1444/*
1445 * While doing rename detection and pickaxe operation, we may need to
1446 * grab the data for the blob (or file) for our own in-core comparison.
1447 * diff_filespec has data and size fields for this purpose.
1448 */
1449int diff_populate_filespec(struct diff_filespec *s, int size_only)
1450{
1451        int err = 0;
1452        if (!DIFF_FILE_VALID(s))
1453                die("internal error: asking to populate invalid file.");
1454        if (S_ISDIR(s->mode))
1455                return -1;
1456
1457        if (s->data)
1458                return 0;
1459
1460        if (size_only && 0 < s->size)
1461                return 0;
1462
1463        if (S_ISGITLINK(s->mode))
1464                return diff_populate_gitlink(s, size_only);
1465
1466        if (!s->sha1_valid ||
1467            reuse_worktree_file(s->path, s->sha1, 0)) {
1468                struct stat st;
1469                int fd;
1470                char *buf;
1471                unsigned long size;
1472
1473                if (!strcmp(s->path, "-"))
1474                        return populate_from_stdin(s);
1475
1476                if (lstat(s->path, &st) < 0) {
1477                        if (errno == ENOENT) {
1478                        err_empty:
1479                                err = -1;
1480                        empty:
1481                                s->data = (char *)"";
1482                                s->size = 0;
1483                                return err;
1484                        }
1485                }
1486                s->size = xsize_t(st.st_size);
1487                if (!s->size)
1488                        goto empty;
1489                if (size_only)
1490                        return 0;
1491                if (S_ISLNK(st.st_mode)) {
1492                        int ret;
1493                        s->data = xmalloc(s->size);
1494                        s->should_free = 1;
1495                        ret = readlink(s->path, s->data, s->size);
1496                        if (ret < 0) {
1497                                free(s->data);
1498                                goto err_empty;
1499                        }
1500                        return 0;
1501                }
1502                fd = open(s->path, O_RDONLY);
1503                if (fd < 0)
1504                        goto err_empty;
1505                s->data = xmmap(NULL, s->size, PROT_READ, MAP_PRIVATE, fd, 0);
1506                close(fd);
1507                s->should_munmap = 1;
1508
1509                /*
1510                 * Convert from working tree format to canonical git format
1511                 */
1512                size = s->size;
1513                buf = convert_to_git(s->path, s->data, &size);
1514                if (buf) {
1515                        munmap(s->data, s->size);
1516                        s->should_munmap = 0;
1517                        s->data = buf;
1518                        s->size = size;
1519                        s->should_free = 1;
1520                }
1521        }
1522        else {
1523                enum object_type type;
1524                if (size_only)
1525                        type = sha1_object_info(s->sha1, &s->size);
1526                else {
1527                        s->data = read_sha1_file(s->sha1, &type, &s->size);
1528                        s->should_free = 1;
1529                }
1530        }
1531        return 0;
1532}
1533
1534void diff_free_filespec_data(struct diff_filespec *s)
1535{
1536        if (s->should_free)
1537                free(s->data);
1538        else if (s->should_munmap)
1539                munmap(s->data, s->size);
1540
1541        if (s->should_free || s->should_munmap) {
1542                s->should_free = s->should_munmap = 0;
1543                s->data = NULL;
1544        }
1545        free(s->cnt_data);
1546        s->cnt_data = NULL;
1547}
1548
1549static void prep_temp_blob(struct diff_tempfile *temp,
1550                           void *blob,
1551                           unsigned long size,
1552                           const unsigned char *sha1,
1553                           int mode)
1554{
1555        int fd;
1556
1557        fd = git_mkstemp(temp->tmp_path, PATH_MAX, ".diff_XXXXXX");
1558        if (fd < 0)
1559                die("unable to create temp-file");
1560        if (write_in_full(fd, blob, size) != size)
1561                die("unable to write temp-file");
1562        close(fd);
1563        temp->name = temp->tmp_path;
1564        strcpy(temp->hex, sha1_to_hex(sha1));
1565        temp->hex[40] = 0;
1566        sprintf(temp->mode, "%06o", mode);
1567}
1568
1569static void prepare_temp_file(const char *name,
1570                              struct diff_tempfile *temp,
1571                              struct diff_filespec *one)
1572{
1573        if (!DIFF_FILE_VALID(one)) {
1574        not_a_valid_file:
1575                /* A '-' entry produces this for file-2, and
1576                 * a '+' entry produces this for file-1.
1577                 */
1578                temp->name = "/dev/null";
1579                strcpy(temp->hex, ".");
1580                strcpy(temp->mode, ".");
1581                return;
1582        }
1583
1584        if (!one->sha1_valid ||
1585            reuse_worktree_file(name, one->sha1, 1)) {
1586                struct stat st;
1587                if (lstat(name, &st) < 0) {
1588                        if (errno == ENOENT)
1589                                goto not_a_valid_file;
1590                        die("stat(%s): %s", name, strerror(errno));
1591                }
1592                if (S_ISLNK(st.st_mode)) {
1593                        int ret;
1594                        char buf[PATH_MAX + 1]; /* ought to be SYMLINK_MAX */
1595                        size_t sz = xsize_t(st.st_size);
1596                        if (sizeof(buf) <= st.st_size)
1597                                die("symlink too long: %s", name);
1598                        ret = readlink(name, buf, sz);
1599                        if (ret < 0)
1600                                die("readlink(%s)", name);
1601                        prep_temp_blob(temp, buf, sz,
1602                                       (one->sha1_valid ?
1603                                        one->sha1 : null_sha1),
1604                                       (one->sha1_valid ?
1605                                        one->mode : S_IFLNK));
1606                }
1607                else {
1608                        /* we can borrow from the file in the work tree */
1609                        temp->name = name;
1610                        if (!one->sha1_valid)
1611                                strcpy(temp->hex, sha1_to_hex(null_sha1));
1612                        else
1613                                strcpy(temp->hex, sha1_to_hex(one->sha1));
1614                        /* Even though we may sometimes borrow the
1615                         * contents from the work tree, we always want
1616                         * one->mode.  mode is trustworthy even when
1617                         * !(one->sha1_valid), as long as
1618                         * DIFF_FILE_VALID(one).
1619                         */
1620                        sprintf(temp->mode, "%06o", one->mode);
1621                }
1622                return;
1623        }
1624        else {
1625                if (diff_populate_filespec(one, 0))
1626                        die("cannot read data blob for %s", one->path);
1627                prep_temp_blob(temp, one->data, one->size,
1628                               one->sha1, one->mode);
1629        }
1630}
1631
1632static void remove_tempfile(void)
1633{
1634        int i;
1635
1636        for (i = 0; i < 2; i++)
1637                if (diff_temp[i].name == diff_temp[i].tmp_path) {
1638                        unlink(diff_temp[i].name);
1639                        diff_temp[i].name = NULL;
1640                }
1641}
1642
1643static void remove_tempfile_on_signal(int signo)
1644{
1645        remove_tempfile();
1646        signal(SIGINT, SIG_DFL);
1647        raise(signo);
1648}
1649
1650static int spawn_prog(const char *pgm, const char **arg)
1651{
1652        pid_t pid;
1653        int status;
1654
1655        fflush(NULL);
1656        pid = fork();
1657        if (pid < 0)
1658                die("unable to fork");
1659        if (!pid) {
1660                execvp(pgm, (char *const*) arg);
1661                exit(255);
1662        }
1663
1664        while (waitpid(pid, &status, 0) < 0) {
1665                if (errno == EINTR)
1666                        continue;
1667                return -1;
1668        }
1669
1670        /* Earlier we did not check the exit status because
1671         * diff exits non-zero if files are different, and
1672         * we are not interested in knowing that.  It was a
1673         * mistake which made it harder to quit a diff-*
1674         * session that uses the git-apply-patch-script as
1675         * the GIT_EXTERNAL_DIFF.  A custom GIT_EXTERNAL_DIFF
1676         * should also exit non-zero only when it wants to
1677         * abort the entire diff-* session.
1678         */
1679        if (WIFEXITED(status) && !WEXITSTATUS(status))
1680                return 0;
1681        return -1;
1682}
1683
1684/* An external diff command takes:
1685 *
1686 * diff-cmd name infile1 infile1-sha1 infile1-mode \
1687 *               infile2 infile2-sha1 infile2-mode [ rename-to ]
1688 *
1689 */
1690static void run_external_diff(const char *pgm,
1691                              const char *name,
1692                              const char *other,
1693                              struct diff_filespec *one,
1694                              struct diff_filespec *two,
1695                              const char *xfrm_msg,
1696                              int complete_rewrite)
1697{
1698        const char *spawn_arg[10];
1699        struct diff_tempfile *temp = diff_temp;
1700        int retval;
1701        static int atexit_asked = 0;
1702        const char *othername;
1703        const char **arg = &spawn_arg[0];
1704
1705        othername = (other? other : name);
1706        if (one && two) {
1707                prepare_temp_file(name, &temp[0], one);
1708                prepare_temp_file(othername, &temp[1], two);
1709                if (! atexit_asked &&
1710                    (temp[0].name == temp[0].tmp_path ||
1711                     temp[1].name == temp[1].tmp_path)) {
1712                        atexit_asked = 1;
1713                        atexit(remove_tempfile);
1714                }
1715                signal(SIGINT, remove_tempfile_on_signal);
1716        }
1717
1718        if (one && two) {
1719                *arg++ = pgm;
1720                *arg++ = name;
1721                *arg++ = temp[0].name;
1722                *arg++ = temp[0].hex;
1723                *arg++ = temp[0].mode;
1724                *arg++ = temp[1].name;
1725                *arg++ = temp[1].hex;
1726                *arg++ = temp[1].mode;
1727                if (other) {
1728                        *arg++ = other;
1729                        *arg++ = xfrm_msg;
1730                }
1731        } else {
1732                *arg++ = pgm;
1733                *arg++ = name;
1734        }
1735        *arg = NULL;
1736        retval = spawn_prog(pgm, spawn_arg);
1737        remove_tempfile();
1738        if (retval) {
1739                fprintf(stderr, "external diff died, stopping at %s.\n", name);
1740                exit(1);
1741        }
1742}
1743
1744static const char *external_diff_attr(const char *name)
1745{
1746        struct git_attr_check attr_diff_check;
1747
1748        setup_diff_attr_check(&attr_diff_check);
1749        if (!git_checkattr(name, 1, &attr_diff_check)) {
1750                const char *value = attr_diff_check.value;
1751                if (!ATTR_TRUE(value) &&
1752                    !ATTR_FALSE(value) &&
1753                    !ATTR_UNSET(value)) {
1754                        struct ll_diff_driver *drv;
1755
1756                        if (!user_diff_tail) {
1757                                user_diff_tail = &user_diff;
1758                                git_config(git_diff_ui_config);
1759                        }
1760                        for (drv = user_diff; drv; drv = drv->next)
1761                                if (!strcmp(drv->name, value))
1762                                        return drv->cmd;
1763                }
1764        }
1765        return NULL;
1766}
1767
1768static void run_diff_cmd(const char *pgm,
1769                         const char *name,
1770                         const char *other,
1771                         struct diff_filespec *one,
1772                         struct diff_filespec *two,
1773                         const char *xfrm_msg,
1774                         struct diff_options *o,
1775                         int complete_rewrite)
1776{
1777        if (!o->allow_external)
1778                pgm = NULL;
1779        else {
1780                const char *cmd = external_diff_attr(name);
1781                if (cmd)
1782                        pgm = cmd;
1783        }
1784
1785        if (pgm) {
1786                run_external_diff(pgm, name, other, one, two, xfrm_msg,
1787                                  complete_rewrite);
1788                return;
1789        }
1790        if (one && two)
1791                builtin_diff(name, other ? other : name,
1792                             one, two, xfrm_msg, o, complete_rewrite);
1793        else
1794                printf("* Unmerged path %s\n", name);
1795}
1796
1797static void diff_fill_sha1_info(struct diff_filespec *one)
1798{
1799        if (DIFF_FILE_VALID(one)) {
1800                if (!one->sha1_valid) {
1801                        struct stat st;
1802                        if (!strcmp(one->path, "-")) {
1803                                hashcpy(one->sha1, null_sha1);
1804                                return;
1805                        }
1806                        if (lstat(one->path, &st) < 0)
1807                                die("stat %s", one->path);
1808                        if (index_path(one->sha1, one->path, &st, 0))
1809                                die("cannot hash %s\n", one->path);
1810                }
1811        }
1812        else
1813                hashclr(one->sha1);
1814}
1815
1816static void run_diff(struct diff_filepair *p, struct diff_options *o)
1817{
1818        const char *pgm = external_diff();
1819        char msg[PATH_MAX*2+300], *xfrm_msg;
1820        struct diff_filespec *one;
1821        struct diff_filespec *two;
1822        const char *name;
1823        const char *other;
1824        char *name_munged, *other_munged;
1825        int complete_rewrite = 0;
1826        int len;
1827
1828        if (DIFF_PAIR_UNMERGED(p)) {
1829                /* unmerged */
1830                run_diff_cmd(pgm, p->one->path, NULL, NULL, NULL, NULL, o, 0);
1831                return;
1832        }
1833
1834        name = p->one->path;
1835        other = (strcmp(name, p->two->path) ? p->two->path : NULL);
1836        name_munged = quote_one(name);
1837        other_munged = quote_one(other);
1838        one = p->one; two = p->two;
1839
1840        diff_fill_sha1_info(one);
1841        diff_fill_sha1_info(two);
1842
1843        len = 0;
1844        switch (p->status) {
1845        case DIFF_STATUS_COPIED:
1846                len += snprintf(msg + len, sizeof(msg) - len,
1847                                "similarity index %d%%\n"
1848                                "copy from %s\n"
1849                                "copy to %s\n",
1850                                (int)(0.5 + p->score * 100.0/MAX_SCORE),
1851                                name_munged, other_munged);
1852                break;
1853        case DIFF_STATUS_RENAMED:
1854                len += snprintf(msg + len, sizeof(msg) - len,
1855                                "similarity index %d%%\n"
1856                                "rename from %s\n"
1857                                "rename to %s\n",
1858                                (int)(0.5 + p->score * 100.0/MAX_SCORE),
1859                                name_munged, other_munged);
1860                break;
1861        case DIFF_STATUS_MODIFIED:
1862                if (p->score) {
1863                        len += snprintf(msg + len, sizeof(msg) - len,
1864                                        "dissimilarity index %d%%\n",
1865                                        (int)(0.5 + p->score *
1866                                              100.0/MAX_SCORE));
1867                        complete_rewrite = 1;
1868                        break;
1869                }
1870                /* fallthru */
1871        default:
1872                /* nothing */
1873                ;
1874        }
1875
1876        if (hashcmp(one->sha1, two->sha1)) {
1877                int abbrev = o->full_index ? 40 : DEFAULT_ABBREV;
1878
1879                if (o->binary) {
1880                        mmfile_t mf;
1881                        if ((!fill_mmfile(&mf, one) && file_is_binary(one)) ||
1882                            (!fill_mmfile(&mf, two) && file_is_binary(two)))
1883                                abbrev = 40;
1884                }
1885                len += snprintf(msg + len, sizeof(msg) - len,
1886                                "index %.*s..%.*s",
1887                                abbrev, sha1_to_hex(one->sha1),
1888                                abbrev, sha1_to_hex(two->sha1));
1889                if (one->mode == two->mode)
1890                        len += snprintf(msg + len, sizeof(msg) - len,
1891                                        " %06o", one->mode);
1892                len += snprintf(msg + len, sizeof(msg) - len, "\n");
1893        }
1894
1895        if (len)
1896                msg[--len] = 0;
1897        xfrm_msg = len ? msg : NULL;
1898
1899        if (!pgm &&
1900            DIFF_FILE_VALID(one) && DIFF_FILE_VALID(two) &&
1901            (S_IFMT & one->mode) != (S_IFMT & two->mode)) {
1902                /* a filepair that changes between file and symlink
1903                 * needs to be split into deletion and creation.
1904                 */
1905                struct diff_filespec *null = alloc_filespec(two->path);
1906                run_diff_cmd(NULL, name, other, one, null, xfrm_msg, o, 0);
1907                free(null);
1908                null = alloc_filespec(one->path);
1909                run_diff_cmd(NULL, name, other, null, two, xfrm_msg, o, 0);
1910                free(null);
1911        }
1912        else
1913                run_diff_cmd(pgm, name, other, one, two, xfrm_msg, o,
1914                             complete_rewrite);
1915
1916        free(name_munged);
1917        free(other_munged);
1918}
1919
1920static void run_diffstat(struct diff_filepair *p, struct diff_options *o,
1921                         struct diffstat_t *diffstat)
1922{
1923        const char *name;
1924        const char *other;
1925        int complete_rewrite = 0;
1926
1927        if (DIFF_PAIR_UNMERGED(p)) {
1928                /* unmerged */
1929                builtin_diffstat(p->one->path, NULL, NULL, NULL, diffstat, o, 0);
1930                return;
1931        }
1932
1933        name = p->one->path;
1934        other = (strcmp(name, p->two->path) ? p->two->path : NULL);
1935
1936        diff_fill_sha1_info(p->one);
1937        diff_fill_sha1_info(p->two);
1938
1939        if (p->status == DIFF_STATUS_MODIFIED && p->score)
1940                complete_rewrite = 1;
1941        builtin_diffstat(name, other, p->one, p->two, diffstat, o, complete_rewrite);
1942}
1943
1944static void run_checkdiff(struct diff_filepair *p, struct diff_options *o)
1945{
1946        const char *name;
1947        const char *other;
1948
1949        if (DIFF_PAIR_UNMERGED(p)) {
1950                /* unmerged */
1951                return;
1952        }
1953
1954        name = p->one->path;
1955        other = (strcmp(name, p->two->path) ? p->two->path : NULL);
1956
1957        diff_fill_sha1_info(p->one);
1958        diff_fill_sha1_info(p->two);
1959
1960        builtin_checkdiff(name, other, p->one, p->two, o);
1961}
1962
1963void diff_setup(struct diff_options *options)
1964{
1965        memset(options, 0, sizeof(*options));
1966        options->line_termination = '\n';
1967        options->break_opt = -1;
1968        options->rename_limit = -1;
1969        options->context = 3;
1970        options->msg_sep = "";
1971
1972        options->change = diff_change;
1973        options->add_remove = diff_addremove;
1974        options->color_diff = diff_use_color_default;
1975        options->detect_rename = diff_detect_rename_default;
1976}
1977
1978int diff_setup_done(struct diff_options *options)
1979{
1980        int count = 0;
1981
1982        if (options->output_format & DIFF_FORMAT_NAME)
1983                count++;
1984        if (options->output_format & DIFF_FORMAT_NAME_STATUS)
1985                count++;
1986        if (options->output_format & DIFF_FORMAT_CHECKDIFF)
1987                count++;
1988        if (options->output_format & DIFF_FORMAT_NO_OUTPUT)
1989                count++;
1990        if (count > 1)
1991                die("--name-only, --name-status, --check and -s are mutually exclusive");
1992
1993        if (options->find_copies_harder)
1994                options->detect_rename = DIFF_DETECT_COPY;
1995
1996        if (options->output_format & (DIFF_FORMAT_NAME |
1997                                      DIFF_FORMAT_NAME_STATUS |
1998                                      DIFF_FORMAT_CHECKDIFF |
1999                                      DIFF_FORMAT_NO_OUTPUT))
2000                options->output_format &= ~(DIFF_FORMAT_RAW |
2001                                            DIFF_FORMAT_NUMSTAT |
2002                                            DIFF_FORMAT_DIFFSTAT |
2003                                            DIFF_FORMAT_SHORTSTAT |
2004                                            DIFF_FORMAT_SUMMARY |
2005                                            DIFF_FORMAT_PATCH);
2006
2007        /*
2008         * These cases always need recursive; we do not drop caller-supplied
2009         * recursive bits for other formats here.
2010         */
2011        if (options->output_format & (DIFF_FORMAT_PATCH |
2012                                      DIFF_FORMAT_NUMSTAT |
2013                                      DIFF_FORMAT_DIFFSTAT |
2014                                      DIFF_FORMAT_SHORTSTAT |
2015                                      DIFF_FORMAT_SUMMARY |
2016                                      DIFF_FORMAT_CHECKDIFF))
2017                options->recursive = 1;
2018        /*
2019         * Also pickaxe would not work very well if you do not say recursive
2020         */
2021        if (options->pickaxe)
2022                options->recursive = 1;
2023
2024        if (options->detect_rename && options->rename_limit < 0)
2025                options->rename_limit = diff_rename_limit_default;
2026        if (options->setup & DIFF_SETUP_USE_CACHE) {
2027                if (!active_cache)
2028                        /* read-cache does not die even when it fails
2029                         * so it is safe for us to do this here.  Also
2030                         * it does not smudge active_cache or active_nr
2031                         * when it fails, so we do not have to worry about
2032                         * cleaning it up ourselves either.
2033                         */
2034                        read_cache();
2035        }
2036        if (options->abbrev <= 0 || 40 < options->abbrev)
2037                options->abbrev = 40; /* full */
2038
2039        /*
2040         * It does not make sense to show the first hit we happened
2041         * to have found.  It does not make sense not to return with
2042         * exit code in such a case either.
2043         */
2044        if (options->quiet) {
2045                options->output_format = DIFF_FORMAT_NO_OUTPUT;
2046                options->exit_with_status = 1;
2047        }
2048
2049        /*
2050         * If we postprocess in diffcore, we cannot simply return
2051         * upon the first hit.  We need to run diff as usual.
2052         */
2053        if (options->pickaxe || options->filter)
2054                options->quiet = 0;
2055
2056        return 0;
2057}
2058
2059static int opt_arg(const char *arg, int arg_short, const char *arg_long, int *val)
2060{
2061        char c, *eq;
2062        int len;
2063
2064        if (*arg != '-')
2065                return 0;
2066        c = *++arg;
2067        if (!c)
2068                return 0;
2069        if (c == arg_short) {
2070                c = *++arg;
2071                if (!c)
2072                        return 1;
2073                if (val && isdigit(c)) {
2074                        char *end;
2075                        int n = strtoul(arg, &end, 10);
2076                        if (*end)
2077                                return 0;
2078                        *val = n;
2079                        return 1;
2080                }
2081                return 0;
2082        }
2083        if (c != '-')
2084                return 0;
2085        arg++;
2086        eq = strchr(arg, '=');
2087        if (eq)
2088                len = eq - arg;
2089        else
2090                len = strlen(arg);
2091        if (!len || strncmp(arg, arg_long, len))
2092                return 0;
2093        if (eq) {
2094                int n;
2095                char *end;
2096                if (!isdigit(*++eq))
2097                        return 0;
2098                n = strtoul(eq, &end, 10);
2099                if (*end)
2100                        return 0;
2101                *val = n;
2102        }
2103        return 1;
2104}
2105
2106int diff_opt_parse(struct diff_options *options, const char **av, int ac)
2107{
2108        const char *arg = av[0];
2109        if (!strcmp(arg, "-p") || !strcmp(arg, "-u"))
2110                options->output_format |= DIFF_FORMAT_PATCH;
2111        else if (opt_arg(arg, 'U', "unified", &options->context))
2112                options->output_format |= DIFF_FORMAT_PATCH;
2113        else if (!strcmp(arg, "--raw"))
2114                options->output_format |= DIFF_FORMAT_RAW;
2115        else if (!strcmp(arg, "--patch-with-raw")) {
2116                options->output_format |= DIFF_FORMAT_PATCH | DIFF_FORMAT_RAW;
2117        }
2118        else if (!strcmp(arg, "--numstat")) {
2119                options->output_format |= DIFF_FORMAT_NUMSTAT;
2120        }
2121        else if (!strcmp(arg, "--shortstat")) {
2122                options->output_format |= DIFF_FORMAT_SHORTSTAT;
2123        }
2124        else if (!prefixcmp(arg, "--stat")) {
2125                char *end;
2126                int width = options->stat_width;
2127                int name_width = options->stat_name_width;
2128                arg += 6;
2129                end = (char *)arg;
2130
2131                switch (*arg) {
2132                case '-':
2133                        if (!prefixcmp(arg, "-width="))
2134                                width = strtoul(arg + 7, &end, 10);
2135                        else if (!prefixcmp(arg, "-name-width="))
2136                                name_width = strtoul(arg + 12, &end, 10);
2137                        break;
2138                case '=':
2139                        width = strtoul(arg+1, &end, 10);
2140                        if (*end == ',')
2141                                name_width = strtoul(end+1, &end, 10);
2142                }
2143
2144                /* Important! This checks all the error cases! */
2145                if (*end)
2146                        return 0;
2147                options->output_format |= DIFF_FORMAT_DIFFSTAT;
2148                options->stat_name_width = name_width;
2149                options->stat_width = width;
2150        }
2151        else if (!strcmp(arg, "--check"))
2152                options->output_format |= DIFF_FORMAT_CHECKDIFF;
2153        else if (!strcmp(arg, "--summary"))
2154                options->output_format |= DIFF_FORMAT_SUMMARY;
2155        else if (!strcmp(arg, "--patch-with-stat")) {
2156                options->output_format |= DIFF_FORMAT_PATCH | DIFF_FORMAT_DIFFSTAT;
2157        }
2158        else if (!strcmp(arg, "-z"))
2159                options->line_termination = 0;
2160        else if (!prefixcmp(arg, "-l"))
2161                options->rename_limit = strtoul(arg+2, NULL, 10);
2162        else if (!strcmp(arg, "--full-index"))
2163                options->full_index = 1;
2164        else if (!strcmp(arg, "--binary")) {
2165                options->output_format |= DIFF_FORMAT_PATCH;
2166                options->binary = 1;
2167        }
2168        else if (!strcmp(arg, "-a") || !strcmp(arg, "--text")) {
2169                options->text = 1;
2170        }
2171        else if (!strcmp(arg, "--name-only"))
2172                options->output_format |= DIFF_FORMAT_NAME;
2173        else if (!strcmp(arg, "--name-status"))
2174                options->output_format |= DIFF_FORMAT_NAME_STATUS;
2175        else if (!strcmp(arg, "-R"))
2176                options->reverse_diff = 1;
2177        else if (!prefixcmp(arg, "-S"))
2178                options->pickaxe = arg + 2;
2179        else if (!strcmp(arg, "-s")) {
2180                options->output_format |= DIFF_FORMAT_NO_OUTPUT;
2181        }
2182        else if (!prefixcmp(arg, "-O"))
2183                options->orderfile = arg + 2;
2184        else if (!prefixcmp(arg, "--diff-filter="))
2185                options->filter = arg + 14;
2186        else if (!strcmp(arg, "--pickaxe-all"))
2187                options->pickaxe_opts = DIFF_PICKAXE_ALL;
2188        else if (!strcmp(arg, "--pickaxe-regex"))
2189                options->pickaxe_opts = DIFF_PICKAXE_REGEX;
2190        else if (!prefixcmp(arg, "-B")) {
2191                if ((options->break_opt =
2192                     diff_scoreopt_parse(arg)) == -1)
2193                        return -1;
2194        }
2195        else if (!prefixcmp(arg, "-M")) {
2196                if ((options->rename_score =
2197                     diff_scoreopt_parse(arg)) == -1)
2198                        return -1;
2199                options->detect_rename = DIFF_DETECT_RENAME;
2200        }
2201        else if (!prefixcmp(arg, "-C")) {
2202                if ((options->rename_score =
2203                     diff_scoreopt_parse(arg)) == -1)
2204                        return -1;
2205                options->detect_rename = DIFF_DETECT_COPY;
2206        }
2207        else if (!strcmp(arg, "--find-copies-harder"))
2208                options->find_copies_harder = 1;
2209        else if (!strcmp(arg, "--abbrev"))
2210                options->abbrev = DEFAULT_ABBREV;
2211        else if (!prefixcmp(arg, "--abbrev=")) {
2212                options->abbrev = strtoul(arg + 9, NULL, 10);
2213                if (options->abbrev < MINIMUM_ABBREV)
2214                        options->abbrev = MINIMUM_ABBREV;
2215                else if (40 < options->abbrev)
2216                        options->abbrev = 40;
2217        }
2218        else if (!strcmp(arg, "--color"))
2219                options->color_diff = 1;
2220        else if (!strcmp(arg, "--no-color"))
2221                options->color_diff = 0;
2222        else if (!strcmp(arg, "-w") || !strcmp(arg, "--ignore-all-space"))
2223                options->xdl_opts |= XDF_IGNORE_WHITESPACE;
2224        else if (!strcmp(arg, "-b") || !strcmp(arg, "--ignore-space-change"))
2225                options->xdl_opts |= XDF_IGNORE_WHITESPACE_CHANGE;
2226        else if (!strcmp(arg, "--ignore-space-at-eol"))
2227                options->xdl_opts |= XDF_IGNORE_WHITESPACE_AT_EOL;
2228        else if (!strcmp(arg, "--color-words"))
2229                options->color_diff = options->color_diff_words = 1;
2230        else if (!strcmp(arg, "--no-renames"))
2231                options->detect_rename = 0;
2232        else if (!strcmp(arg, "--exit-code"))
2233                options->exit_with_status = 1;
2234        else if (!strcmp(arg, "--quiet"))
2235                options->quiet = 1;
2236        else
2237                return 0;
2238        return 1;
2239}
2240
2241static int parse_num(const char **cp_p)
2242{
2243        unsigned long num, scale;
2244        int ch, dot;
2245        const char *cp = *cp_p;
2246
2247        num = 0;
2248        scale = 1;
2249        dot = 0;
2250        for(;;) {
2251                ch = *cp;
2252                if ( !dot && ch == '.' ) {
2253                        scale = 1;
2254                        dot = 1;
2255                } else if ( ch == '%' ) {
2256                        scale = dot ? scale*100 : 100;
2257                        cp++;   /* % is always at the end */
2258                        break;
2259                } else if ( ch >= '0' && ch <= '9' ) {
2260                        if ( scale < 100000 ) {
2261                                scale *= 10;
2262                                num = (num*10) + (ch-'0');
2263                        }
2264                } else {
2265                        break;
2266                }
2267                cp++;
2268        }
2269        *cp_p = cp;
2270
2271        /* user says num divided by scale and we say internally that
2272         * is MAX_SCORE * num / scale.
2273         */
2274        return (int)((num >= scale) ? MAX_SCORE : (MAX_SCORE * num / scale));
2275}
2276
2277int diff_scoreopt_parse(const char *opt)
2278{
2279        int opt1, opt2, cmd;
2280
2281        if (*opt++ != '-')
2282                return -1;
2283        cmd = *opt++;
2284        if (cmd != 'M' && cmd != 'C' && cmd != 'B')
2285                return -1; /* that is not a -M, -C nor -B option */
2286
2287        opt1 = parse_num(&opt);
2288        if (cmd != 'B')
2289                opt2 = 0;
2290        else {
2291                if (*opt == 0)
2292                        opt2 = 0;
2293                else if (*opt != '/')
2294                        return -1; /* we expect -B80/99 or -B80 */
2295                else {
2296                        opt++;
2297                        opt2 = parse_num(&opt);
2298                }
2299        }
2300        if (*opt != 0)
2301                return -1;
2302        return opt1 | (opt2 << 16);
2303}
2304
2305struct diff_queue_struct diff_queued_diff;
2306
2307void diff_q(struct diff_queue_struct *queue, struct diff_filepair *dp)
2308{
2309        if (queue->alloc <= queue->nr) {
2310                queue->alloc = alloc_nr(queue->alloc);
2311                queue->queue = xrealloc(queue->queue,
2312                                        sizeof(dp) * queue->alloc);
2313        }
2314        queue->queue[queue->nr++] = dp;
2315}
2316
2317struct diff_filepair *diff_queue(struct diff_queue_struct *queue,
2318                                 struct diff_filespec *one,
2319                                 struct diff_filespec *two)
2320{
2321        struct diff_filepair *dp = xcalloc(1, sizeof(*dp));
2322        dp->one = one;
2323        dp->two = two;
2324        if (queue)
2325                diff_q(queue, dp);
2326        return dp;
2327}
2328
2329void diff_free_filepair(struct diff_filepair *p)
2330{
2331        diff_free_filespec_data(p->one);
2332        diff_free_filespec_data(p->two);
2333        free(p->one);
2334        free(p->two);
2335        free(p);
2336}
2337
2338/* This is different from find_unique_abbrev() in that
2339 * it stuffs the result with dots for alignment.
2340 */
2341const char *diff_unique_abbrev(const unsigned char *sha1, int len)
2342{
2343        int abblen;
2344        const char *abbrev;
2345        if (len == 40)
2346                return sha1_to_hex(sha1);
2347
2348        abbrev = find_unique_abbrev(sha1, len);
2349        if (!abbrev)
2350                return sha1_to_hex(sha1);
2351        abblen = strlen(abbrev);
2352        if (abblen < 37) {
2353                static char hex[41];
2354                if (len < abblen && abblen <= len + 2)
2355                        sprintf(hex, "%s%.*s", abbrev, len+3-abblen, "..");
2356                else
2357                        sprintf(hex, "%s...", abbrev);
2358                return hex;
2359        }
2360        return sha1_to_hex(sha1);
2361}
2362
2363static void diff_flush_raw(struct diff_filepair *p,
2364                           struct diff_options *options)
2365{
2366        int two_paths;
2367        char status[10];
2368        int abbrev = options->abbrev;
2369        const char *path_one, *path_two;
2370        int inter_name_termination = '\t';
2371        int line_termination = options->line_termination;
2372
2373        if (!line_termination)
2374                inter_name_termination = 0;
2375
2376        path_one = p->one->path;
2377        path_two = p->two->path;
2378        if (line_termination) {
2379                path_one = quote_one(path_one);
2380                path_two = quote_one(path_two);
2381        }
2382
2383        if (p->score)
2384                sprintf(status, "%c%03d", p->status,
2385                        (int)(0.5 + p->score * 100.0/MAX_SCORE));
2386        else {
2387                status[0] = p->status;
2388                status[1] = 0;
2389        }
2390        switch (p->status) {
2391        case DIFF_STATUS_COPIED:
2392        case DIFF_STATUS_RENAMED:
2393                two_paths = 1;
2394                break;
2395        case DIFF_STATUS_ADDED:
2396        case DIFF_STATUS_DELETED:
2397                two_paths = 0;
2398                break;
2399        default:
2400                two_paths = 0;
2401                break;
2402        }
2403        if (!(options->output_format & DIFF_FORMAT_NAME_STATUS)) {
2404                printf(":%06o %06o %s ",
2405                       p->one->mode, p->two->mode,
2406                       diff_unique_abbrev(p->one->sha1, abbrev));
2407                printf("%s ",
2408                       diff_unique_abbrev(p->two->sha1, abbrev));
2409        }
2410        printf("%s%c%s", status, inter_name_termination, path_one);
2411        if (two_paths)
2412                printf("%c%s", inter_name_termination, path_two);
2413        putchar(line_termination);
2414        if (path_one != p->one->path)
2415                free((void*)path_one);
2416        if (path_two != p->two->path)
2417                free((void*)path_two);
2418}
2419
2420static void diff_flush_name(struct diff_filepair *p, struct diff_options *opt)
2421{
2422        char *path = p->two->path;
2423
2424        if (opt->line_termination)
2425                path = quote_one(p->two->path);
2426        printf("%s%c", path, opt->line_termination);
2427        if (p->two->path != path)
2428                free(path);
2429}
2430
2431int diff_unmodified_pair(struct diff_filepair *p)
2432{
2433        /* This function is written stricter than necessary to support
2434         * the currently implemented transformers, but the idea is to
2435         * let transformers to produce diff_filepairs any way they want,
2436         * and filter and clean them up here before producing the output.
2437         */
2438        struct diff_filespec *one, *two;
2439
2440        if (DIFF_PAIR_UNMERGED(p))
2441                return 0; /* unmerged is interesting */
2442
2443        one = p->one;
2444        two = p->two;
2445
2446        /* deletion, addition, mode or type change
2447         * and rename are all interesting.
2448         */
2449        if (DIFF_FILE_VALID(one) != DIFF_FILE_VALID(two) ||
2450            DIFF_PAIR_MODE_CHANGED(p) ||
2451            strcmp(one->path, two->path))
2452                return 0;
2453
2454        /* both are valid and point at the same path.  that is, we are
2455         * dealing with a change.
2456         */
2457        if (one->sha1_valid && two->sha1_valid &&
2458            !hashcmp(one->sha1, two->sha1))
2459                return 1; /* no change */
2460        if (!one->sha1_valid && !two->sha1_valid)
2461                return 1; /* both look at the same file on the filesystem. */
2462        return 0;
2463}
2464
2465static void diff_flush_patch(struct diff_filepair *p, struct diff_options *o)
2466{
2467        if (diff_unmodified_pair(p))
2468                return;
2469
2470        if ((DIFF_FILE_VALID(p->one) && S_ISDIR(p->one->mode)) ||
2471            (DIFF_FILE_VALID(p->two) && S_ISDIR(p->two->mode)))
2472                return; /* no tree diffs in patch format */
2473
2474        run_diff(p, o);
2475}
2476
2477static void diff_flush_stat(struct diff_filepair *p, struct diff_options *o,
2478                            struct diffstat_t *diffstat)
2479{
2480        if (diff_unmodified_pair(p))
2481                return;
2482
2483        if ((DIFF_FILE_VALID(p->one) && S_ISDIR(p->one->mode)) ||
2484            (DIFF_FILE_VALID(p->two) && S_ISDIR(p->two->mode)))
2485                return; /* no tree diffs in patch format */
2486
2487        run_diffstat(p, o, diffstat);
2488}
2489
2490static void diff_flush_checkdiff(struct diff_filepair *p,
2491                struct diff_options *o)
2492{
2493        if (diff_unmodified_pair(p))
2494                return;
2495
2496        if ((DIFF_FILE_VALID(p->one) && S_ISDIR(p->one->mode)) ||
2497            (DIFF_FILE_VALID(p->two) && S_ISDIR(p->two->mode)))
2498                return; /* no tree diffs in patch format */
2499
2500        run_checkdiff(p, o);
2501}
2502
2503int diff_queue_is_empty(void)
2504{
2505        struct diff_queue_struct *q = &diff_queued_diff;
2506        int i;
2507        for (i = 0; i < q->nr; i++)
2508                if (!diff_unmodified_pair(q->queue[i]))
2509                        return 0;
2510        return 1;
2511}
2512
2513#if DIFF_DEBUG
2514void diff_debug_filespec(struct diff_filespec *s, int x, const char *one)
2515{
2516        fprintf(stderr, "queue[%d] %s (%s) %s %06o %s\n",
2517                x, one ? one : "",
2518                s->path,
2519                DIFF_FILE_VALID(s) ? "valid" : "invalid",
2520                s->mode,
2521                s->sha1_valid ? sha1_to_hex(s->sha1) : "");
2522        fprintf(stderr, "queue[%d] %s size %lu flags %d\n",
2523                x, one ? one : "",
2524                s->size, s->xfrm_flags);
2525}
2526
2527void diff_debug_filepair(const struct diff_filepair *p, int i)
2528{
2529        diff_debug_filespec(p->one, i, "one");
2530        diff_debug_filespec(p->two, i, "two");
2531        fprintf(stderr, "score %d, status %c stays %d broken %d\n",
2532                p->score, p->status ? p->status : '?',
2533                p->source_stays, p->broken_pair);
2534}
2535
2536void diff_debug_queue(const char *msg, struct diff_queue_struct *q)
2537{
2538        int i;
2539        if (msg)
2540                fprintf(stderr, "%s\n", msg);
2541        fprintf(stderr, "q->nr = %d\n", q->nr);
2542        for (i = 0; i < q->nr; i++) {
2543                struct diff_filepair *p = q->queue[i];
2544                diff_debug_filepair(p, i);
2545        }
2546}
2547#endif
2548
2549static void diff_resolve_rename_copy(void)
2550{
2551        int i, j;
2552        struct diff_filepair *p, *pp;
2553        struct diff_queue_struct *q = &diff_queued_diff;
2554
2555        diff_debug_queue("resolve-rename-copy", q);
2556
2557        for (i = 0; i < q->nr; i++) {
2558                p = q->queue[i];
2559                p->status = 0; /* undecided */
2560                if (DIFF_PAIR_UNMERGED(p))
2561                        p->status = DIFF_STATUS_UNMERGED;
2562                else if (!DIFF_FILE_VALID(p->one))
2563                        p->status = DIFF_STATUS_ADDED;
2564                else if (!DIFF_FILE_VALID(p->two))
2565                        p->status = DIFF_STATUS_DELETED;
2566                else if (DIFF_PAIR_TYPE_CHANGED(p))
2567                        p->status = DIFF_STATUS_TYPE_CHANGED;
2568
2569                /* from this point on, we are dealing with a pair
2570                 * whose both sides are valid and of the same type, i.e.
2571                 * either in-place edit or rename/copy edit.
2572                 */
2573                else if (DIFF_PAIR_RENAME(p)) {
2574                        if (p->source_stays) {
2575                                p->status = DIFF_STATUS_COPIED;
2576                                continue;
2577                        }
2578                        /* See if there is some other filepair that
2579                         * copies from the same source as us.  If so
2580                         * we are a copy.  Otherwise we are either a
2581                         * copy if the path stays, or a rename if it
2582                         * does not, but we already handled "stays" case.
2583                         */
2584                        for (j = i + 1; j < q->nr; j++) {
2585                                pp = q->queue[j];
2586                                if (strcmp(pp->one->path, p->one->path))
2587                                        continue; /* not us */
2588                                if (!DIFF_PAIR_RENAME(pp))
2589                                        continue; /* not a rename/copy */
2590                                /* pp is a rename/copy from the same source */
2591                                p->status = DIFF_STATUS_COPIED;
2592                                break;
2593                        }
2594                        if (!p->status)
2595                                p->status = DIFF_STATUS_RENAMED;
2596                }
2597                else if (hashcmp(p->one->sha1, p->two->sha1) ||
2598                         p->one->mode != p->two->mode ||
2599                         is_null_sha1(p->one->sha1))
2600                        p->status = DIFF_STATUS_MODIFIED;
2601                else {
2602                        /* This is a "no-change" entry and should not
2603                         * happen anymore, but prepare for broken callers.
2604                         */
2605                        error("feeding unmodified %s to diffcore",
2606                              p->one->path);
2607                        p->status = DIFF_STATUS_UNKNOWN;
2608                }
2609        }
2610        diff_debug_queue("resolve-rename-copy done", q);
2611}
2612
2613static int check_pair_status(struct diff_filepair *p)
2614{
2615        switch (p->status) {
2616        case DIFF_STATUS_UNKNOWN:
2617                return 0;
2618        case 0:
2619                die("internal error in diff-resolve-rename-copy");
2620        default:
2621                return 1;
2622        }
2623}
2624
2625static void flush_one_pair(struct diff_filepair *p, struct diff_options *opt)
2626{
2627        int fmt = opt->output_format;
2628
2629        if (fmt & DIFF_FORMAT_CHECKDIFF)
2630                diff_flush_checkdiff(p, opt);
2631        else if (fmt & (DIFF_FORMAT_RAW | DIFF_FORMAT_NAME_STATUS))
2632                diff_flush_raw(p, opt);
2633        else if (fmt & DIFF_FORMAT_NAME)
2634                diff_flush_name(p, opt);
2635}
2636
2637static void show_file_mode_name(const char *newdelete, struct diff_filespec *fs)
2638{
2639        char *name = quote_one(fs->path);
2640        if (fs->mode)
2641                printf(" %s mode %06o %s\n", newdelete, fs->mode, name);
2642        else
2643                printf(" %s %s\n", newdelete, name);
2644        free(name);
2645}
2646
2647
2648static void show_mode_change(struct diff_filepair *p, int show_name)
2649{
2650        if (p->one->mode && p->two->mode && p->one->mode != p->two->mode) {
2651                if (show_name) {
2652                        char *name = quote_one(p->two->path);
2653                        printf(" mode change %06o => %06o %s\n",
2654                               p->one->mode, p->two->mode, name);
2655                        free(name);
2656                }
2657                else
2658                        printf(" mode change %06o => %06o\n",
2659                               p->one->mode, p->two->mode);
2660        }
2661}
2662
2663static void show_rename_copy(const char *renamecopy, struct diff_filepair *p)
2664{
2665        char *names = pprint_rename(p->one->path, p->two->path);
2666
2667        printf(" %s %s (%d%%)\n", renamecopy, names,
2668               (int)(0.5 + p->score * 100.0/MAX_SCORE));
2669        free(names);
2670        show_mode_change(p, 0);
2671}
2672
2673static void diff_summary(struct diff_filepair *p)
2674{
2675        switch(p->status) {
2676        case DIFF_STATUS_DELETED:
2677                show_file_mode_name("delete", p->one);
2678                break;
2679        case DIFF_STATUS_ADDED:
2680                show_file_mode_name("create", p->two);
2681                break;
2682        case DIFF_STATUS_COPIED:
2683                show_rename_copy("copy", p);
2684                break;
2685        case DIFF_STATUS_RENAMED:
2686                show_rename_copy("rename", p);
2687                break;
2688        default:
2689                if (p->score) {
2690                        char *name = quote_one(p->two->path);
2691                        printf(" rewrite %s (%d%%)\n", name,
2692                                (int)(0.5 + p->score * 100.0/MAX_SCORE));
2693                        free(name);
2694                        show_mode_change(p, 0);
2695                } else  show_mode_change(p, 1);
2696                break;
2697        }
2698}
2699
2700struct patch_id_t {
2701        struct xdiff_emit_state xm;
2702        SHA_CTX *ctx;
2703        int patchlen;
2704};
2705
2706static int remove_space(char *line, int len)
2707{
2708        int i;
2709        char *dst = line;
2710        unsigned char c;
2711
2712        for (i = 0; i < len; i++)
2713                if (!isspace((c = line[i])))
2714                        *dst++ = c;
2715
2716        return dst - line;
2717}
2718
2719static void patch_id_consume(void *priv, char *line, unsigned long len)
2720{
2721        struct patch_id_t *data = priv;
2722        int new_len;
2723
2724        /* Ignore line numbers when computing the SHA1 of the patch */
2725        if (!prefixcmp(line, "@@ -"))
2726                return;
2727
2728        new_len = remove_space(line, len);
2729
2730        SHA1_Update(data->ctx, line, new_len);
2731        data->patchlen += new_len;
2732}
2733
2734/* returns 0 upon success, and writes result into sha1 */
2735static int diff_get_patch_id(struct diff_options *options, unsigned char *sha1)
2736{
2737        struct diff_queue_struct *q = &diff_queued_diff;
2738        int i;
2739        SHA_CTX ctx;
2740        struct patch_id_t data;
2741        char buffer[PATH_MAX * 4 + 20];
2742
2743        SHA1_Init(&ctx);
2744        memset(&data, 0, sizeof(struct patch_id_t));
2745        data.ctx = &ctx;
2746        data.xm.consume = patch_id_consume;
2747
2748        for (i = 0; i < q->nr; i++) {
2749                xpparam_t xpp;
2750                xdemitconf_t xecfg;
2751                xdemitcb_t ecb;
2752                mmfile_t mf1, mf2;
2753                struct diff_filepair *p = q->queue[i];
2754                int len1, len2;
2755
2756                if (p->status == 0)
2757                        return error("internal diff status error");
2758                if (p->status == DIFF_STATUS_UNKNOWN)
2759                        continue;
2760                if (diff_unmodified_pair(p))
2761                        continue;
2762                if ((DIFF_FILE_VALID(p->one) && S_ISDIR(p->one->mode)) ||
2763                    (DIFF_FILE_VALID(p->two) && S_ISDIR(p->two->mode)))
2764                        continue;
2765                if (DIFF_PAIR_UNMERGED(p))
2766                        continue;
2767
2768                diff_fill_sha1_info(p->one);
2769                diff_fill_sha1_info(p->two);
2770                if (fill_mmfile(&mf1, p->one) < 0 ||
2771                                fill_mmfile(&mf2, p->two) < 0)
2772                        return error("unable to read files to diff");
2773
2774                /* Maybe hash p->two? into the patch id? */
2775                if (file_is_binary(p->two))
2776                        continue;
2777
2778                len1 = remove_space(p->one->path, strlen(p->one->path));
2779                len2 = remove_space(p->two->path, strlen(p->two->path));
2780                if (p->one->mode == 0)
2781                        len1 = snprintf(buffer, sizeof(buffer),
2782                                        "diff--gita/%.*sb/%.*s"
2783                                        "newfilemode%06o"
2784                                        "---/dev/null"
2785                                        "+++b/%.*s",
2786                                        len1, p->one->path,
2787                                        len2, p->two->path,
2788                                        p->two->mode,
2789                                        len2, p->two->path);
2790                else if (p->two->mode == 0)
2791                        len1 = snprintf(buffer, sizeof(buffer),
2792                                        "diff--gita/%.*sb/%.*s"
2793                                        "deletedfilemode%06o"
2794                                        "---a/%.*s"
2795                                        "+++/dev/null",
2796                                        len1, p->one->path,
2797                                        len2, p->two->path,
2798                                        p->one->mode,
2799                                        len1, p->one->path);
2800                else
2801                        len1 = snprintf(buffer, sizeof(buffer),
2802                                        "diff--gita/%.*sb/%.*s"
2803                                        "---a/%.*s"
2804                                        "+++b/%.*s",
2805                                        len1, p->one->path,
2806                                        len2, p->two->path,
2807                                        len1, p->one->path,
2808                                        len2, p->two->path);
2809                SHA1_Update(&ctx, buffer, len1);
2810
2811                xpp.flags = XDF_NEED_MINIMAL;
2812                xecfg.ctxlen = 3;
2813                xecfg.flags = XDL_EMIT_FUNCNAMES;
2814                ecb.outf = xdiff_outf;
2815                ecb.priv = &data;
2816                xdl_diff(&mf1, &mf2, &xpp, &xecfg, &ecb);
2817        }
2818
2819        SHA1_Final(sha1, &ctx);
2820        return 0;
2821}
2822
2823int diff_flush_patch_id(struct diff_options *options, unsigned char *sha1)
2824{
2825        struct diff_queue_struct *q = &diff_queued_diff;
2826        int i;
2827        int result = diff_get_patch_id(options, sha1);
2828
2829        for (i = 0; i < q->nr; i++)
2830                diff_free_filepair(q->queue[i]);
2831
2832        free(q->queue);
2833        q->queue = NULL;
2834        q->nr = q->alloc = 0;
2835
2836        return result;
2837}
2838
2839static int is_summary_empty(const struct diff_queue_struct *q)
2840{
2841        int i;
2842
2843        for (i = 0; i < q->nr; i++) {
2844                const struct diff_filepair *p = q->queue[i];
2845
2846                switch (p->status) {
2847                case DIFF_STATUS_DELETED:
2848                case DIFF_STATUS_ADDED:
2849                case DIFF_STATUS_COPIED:
2850                case DIFF_STATUS_RENAMED:
2851                        return 0;
2852                default:
2853                        if (p->score)
2854                                return 0;
2855                        if (p->one->mode && p->two->mode &&
2856                            p->one->mode != p->two->mode)
2857                                return 0;
2858                        break;
2859                }
2860        }
2861        return 1;
2862}
2863
2864void diff_flush(struct diff_options *options)
2865{
2866        struct diff_queue_struct *q = &diff_queued_diff;
2867        int i, output_format = options->output_format;
2868        int separator = 0;
2869
2870        /*
2871         * Order: raw, stat, summary, patch
2872         * or:    name/name-status/checkdiff (other bits clear)
2873         */
2874        if (!q->nr)
2875                goto free_queue;
2876
2877        if (output_format & (DIFF_FORMAT_RAW |
2878                             DIFF_FORMAT_NAME |
2879                             DIFF_FORMAT_NAME_STATUS |
2880                             DIFF_FORMAT_CHECKDIFF)) {
2881                for (i = 0; i < q->nr; i++) {
2882                        struct diff_filepair *p = q->queue[i];
2883                        if (check_pair_status(p))
2884                                flush_one_pair(p, options);
2885                }
2886                separator++;
2887        }
2888
2889        if (output_format & (DIFF_FORMAT_DIFFSTAT|DIFF_FORMAT_SHORTSTAT|DIFF_FORMAT_NUMSTAT)) {
2890                struct diffstat_t diffstat;
2891
2892                memset(&diffstat, 0, sizeof(struct diffstat_t));
2893                diffstat.xm.consume = diffstat_consume;
2894                for (i = 0; i < q->nr; i++) {
2895                        struct diff_filepair *p = q->queue[i];
2896                        if (check_pair_status(p))
2897                                diff_flush_stat(p, options, &diffstat);
2898                }
2899                if (output_format & DIFF_FORMAT_NUMSTAT)
2900                        show_numstat(&diffstat, options);
2901                if (output_format & DIFF_FORMAT_DIFFSTAT)
2902                        show_stats(&diffstat, options);
2903                else if (output_format & DIFF_FORMAT_SHORTSTAT)
2904                        show_shortstats(&diffstat);
2905                separator++;
2906        }
2907
2908        if (output_format & DIFF_FORMAT_SUMMARY && !is_summary_empty(q)) {
2909                for (i = 0; i < q->nr; i++)
2910                        diff_summary(q->queue[i]);
2911                separator++;
2912        }
2913
2914        if (output_format & DIFF_FORMAT_PATCH) {
2915                if (separator) {
2916                        if (options->stat_sep) {
2917                                /* attach patch instead of inline */
2918                                fputs(options->stat_sep, stdout);
2919                        } else {
2920                                putchar(options->line_termination);
2921                        }
2922                }
2923
2924                for (i = 0; i < q->nr; i++) {
2925                        struct diff_filepair *p = q->queue[i];
2926                        if (check_pair_status(p))
2927                                diff_flush_patch(p, options);
2928                }
2929        }
2930
2931        if (output_format & DIFF_FORMAT_CALLBACK)
2932                options->format_callback(q, options, options->format_callback_data);
2933
2934        for (i = 0; i < q->nr; i++)
2935                diff_free_filepair(q->queue[i]);
2936free_queue:
2937        free(q->queue);
2938        q->queue = NULL;
2939        q->nr = q->alloc = 0;
2940}
2941
2942static void diffcore_apply_filter(const char *filter)
2943{
2944        int i;
2945        struct diff_queue_struct *q = &diff_queued_diff;
2946        struct diff_queue_struct outq;
2947        outq.queue = NULL;
2948        outq.nr = outq.alloc = 0;
2949
2950        if (!filter)
2951                return;
2952
2953        if (strchr(filter, DIFF_STATUS_FILTER_AON)) {
2954                int found;
2955                for (i = found = 0; !found && i < q->nr; i++) {
2956                        struct diff_filepair *p = q->queue[i];
2957                        if (((p->status == DIFF_STATUS_MODIFIED) &&
2958                             ((p->score &&
2959                               strchr(filter, DIFF_STATUS_FILTER_BROKEN)) ||
2960                              (!p->score &&
2961                               strchr(filter, DIFF_STATUS_MODIFIED)))) ||
2962                            ((p->status != DIFF_STATUS_MODIFIED) &&
2963                             strchr(filter, p->status)))
2964                                found++;
2965                }
2966                if (found)
2967                        return;
2968
2969                /* otherwise we will clear the whole queue
2970                 * by copying the empty outq at the end of this
2971                 * function, but first clear the current entries
2972                 * in the queue.
2973                 */
2974                for (i = 0; i < q->nr; i++)
2975                        diff_free_filepair(q->queue[i]);
2976        }
2977        else {
2978                /* Only the matching ones */
2979                for (i = 0; i < q->nr; i++) {
2980                        struct diff_filepair *p = q->queue[i];
2981
2982                        if (((p->status == DIFF_STATUS_MODIFIED) &&
2983                             ((p->score &&
2984                               strchr(filter, DIFF_STATUS_FILTER_BROKEN)) ||
2985                              (!p->score &&
2986                               strchr(filter, DIFF_STATUS_MODIFIED)))) ||
2987                            ((p->status != DIFF_STATUS_MODIFIED) &&
2988                             strchr(filter, p->status)))
2989                                diff_q(&outq, p);
2990                        else
2991                                diff_free_filepair(p);
2992                }
2993        }
2994        free(q->queue);
2995        *q = outq;
2996}
2997
2998void diffcore_std(struct diff_options *options)
2999{
3000        if (options->quiet)
3001                return;
3002        if (options->break_opt != -1)
3003                diffcore_break(options->break_opt);
3004        if (options->detect_rename)
3005                diffcore_rename(options);
3006        if (options->break_opt != -1)
3007                diffcore_merge_broken();
3008        if (options->pickaxe)
3009                diffcore_pickaxe(options->pickaxe, options->pickaxe_opts);
3010        if (options->orderfile)
3011                diffcore_order(options->orderfile);
3012        diff_resolve_rename_copy();
3013        diffcore_apply_filter(options->filter);
3014
3015        options->has_changes = !!diff_queued_diff.nr;
3016}
3017
3018
3019void diff_addremove(struct diff_options *options,
3020                    int addremove, unsigned mode,
3021                    const unsigned char *sha1,
3022                    const char *base, const char *path)
3023{
3024        char concatpath[PATH_MAX];
3025        struct diff_filespec *one, *two;
3026
3027        /* This may look odd, but it is a preparation for
3028         * feeding "there are unchanged files which should
3029         * not produce diffs, but when you are doing copy
3030         * detection you would need them, so here they are"
3031         * entries to the diff-core.  They will be prefixed
3032         * with something like '=' or '*' (I haven't decided
3033         * which but should not make any difference).
3034         * Feeding the same new and old to diff_change() 
3035         * also has the same effect.
3036         * Before the final output happens, they are pruned after
3037         * merged into rename/copy pairs as appropriate.
3038         */
3039        if (options->reverse_diff)
3040                addremove = (addremove == '+' ? '-' :
3041                             addremove == '-' ? '+' : addremove);
3042
3043        if (!path) path = "";
3044        sprintf(concatpath, "%s%s", base, path);
3045        one = alloc_filespec(concatpath);
3046        two = alloc_filespec(concatpath);
3047
3048        if (addremove != '+')
3049                fill_filespec(one, sha1, mode);
3050        if (addremove != '-')
3051                fill_filespec(two, sha1, mode);
3052
3053        diff_queue(&diff_queued_diff, one, two);
3054        options->has_changes = 1;
3055}
3056
3057void diff_change(struct diff_options *options,
3058                 unsigned old_mode, unsigned new_mode,
3059                 const unsigned char *old_sha1,
3060                 const unsigned char *new_sha1,
3061                 const char *base, const char *path) 
3062{
3063        char concatpath[PATH_MAX];
3064        struct diff_filespec *one, *two;
3065
3066        if (options->reverse_diff) {
3067                unsigned tmp;
3068                const unsigned char *tmp_c;
3069                tmp = old_mode; old_mode = new_mode; new_mode = tmp;
3070                tmp_c = old_sha1; old_sha1 = new_sha1; new_sha1 = tmp_c;
3071        }
3072        if (!path) path = "";
3073        sprintf(concatpath, "%s%s", base, path);
3074        one = alloc_filespec(concatpath);
3075        two = alloc_filespec(concatpath);
3076        fill_filespec(one, old_sha1, old_mode);
3077        fill_filespec(two, new_sha1, new_mode);
3078
3079        diff_queue(&diff_queued_diff, one, two);
3080        options->has_changes = 1;
3081}
3082
3083void diff_unmerge(struct diff_options *options,
3084                  const char *path,
3085                  unsigned mode, const unsigned char *sha1)
3086{
3087        struct diff_filespec *one, *two;
3088        one = alloc_filespec(path);
3089        two = alloc_filespec(path);
3090        fill_filespec(one, sha1, mode);
3091        diff_queue(&diff_queued_diff, one, two)->is_unmerged = 1;
3092}