diff.con commit diff --color: use $GIT_DIR/config (801235c)
   1/*
   2 * Copyright (C) 2005 Junio C Hamano
   3 */
   4#include <sys/types.h>
   5#include <sys/wait.h>
   6#include <signal.h>
   7#include "cache.h"
   8#include "quote.h"
   9#include "diff.h"
  10#include "diffcore.h"
  11#include "delta.h"
  12#include "xdiff-interface.h"
  13
  14static int use_size_cache;
  15
  16static int diff_rename_limit_default = -1;
  17static int diff_use_color_default = 0;
  18
  19enum color_diff {
  20        DIFF_RESET = 0,
  21        DIFF_PLAIN = 1,
  22        DIFF_METAINFO = 2,
  23        DIFF_FRAGINFO = 3,
  24        DIFF_FILE_OLD = 4,
  25        DIFF_FILE_NEW = 5,
  26};
  27
  28#define COLOR_NORMAL  ""
  29#define COLOR_BOLD    "\033[1m"
  30#define COLOR_DIM     "\033[2m"
  31#define COLOR_UL      "\033[4m"
  32#define COLOR_BLINK   "\033[5m"
  33#define COLOR_REVERSE "\033[7m"
  34#define COLOR_RESET   "\033[m"
  35
  36#define COLOR_BLACK   "\033[30m"
  37#define COLOR_RED     "\033[31m"
  38#define COLOR_GREEN   "\033[32m"
  39#define COLOR_YELLOW  "\033[33m"
  40#define COLOR_BLUE    "\033[34m"
  41#define COLOR_MAGENTA "\033[35m"
  42#define COLOR_CYAN    "\033[36m"
  43#define COLOR_WHITE   "\033[37m"
  44
  45static const char *diff_colors[] = {
  46        [DIFF_RESET]    = COLOR_RESET,
  47        [DIFF_PLAIN]    = COLOR_NORMAL,
  48        [DIFF_METAINFO] = COLOR_BOLD,
  49        [DIFF_FRAGINFO] = COLOR_CYAN,
  50        [DIFF_FILE_OLD] = COLOR_RED,
  51        [DIFF_FILE_NEW] = COLOR_GREEN,
  52};
  53
  54static int parse_diff_color_slot(const char *var, int ofs)
  55{
  56        if (!strcasecmp(var+ofs, "plain"))
  57                return DIFF_PLAIN;
  58        if (!strcasecmp(var+ofs, "meta"))
  59                return DIFF_METAINFO;
  60        if (!strcasecmp(var+ofs, "frag"))
  61                return DIFF_FRAGINFO;
  62        if (!strcasecmp(var+ofs, "old"))
  63                return DIFF_FILE_OLD;
  64        if (!strcasecmp(var+ofs, "new"))
  65                return DIFF_FILE_NEW;
  66        die("bad config variable '%s'", var);
  67}
  68
  69static const char *parse_diff_color_value(const char *value, const char *var)
  70{
  71        if (!strcasecmp(value, "normal"))
  72                return COLOR_NORMAL;
  73        if (!strcasecmp(value, "bold"))
  74                return COLOR_BOLD;
  75        if (!strcasecmp(value, "dim"))
  76                return COLOR_DIM;
  77        if (!strcasecmp(value, "ul"))
  78                return COLOR_UL;
  79        if (!strcasecmp(value, "blink"))
  80                return COLOR_BLINK;
  81        if (!strcasecmp(value, "reverse"))
  82                return COLOR_REVERSE;
  83        if (!strcasecmp(value, "reset"))
  84                return COLOR_RESET;
  85        if (!strcasecmp(value, "black"))
  86                return COLOR_BLACK;
  87        if (!strcasecmp(value, "red"))
  88                return COLOR_RED;
  89        if (!strcasecmp(value, "green"))
  90                return COLOR_GREEN;
  91        if (!strcasecmp(value, "yellow"))
  92                return COLOR_YELLOW;
  93        if (!strcasecmp(value, "blue"))
  94                return COLOR_BLUE;
  95        if (!strcasecmp(value, "magenta"))
  96                return COLOR_MAGENTA;
  97        if (!strcasecmp(value, "cyan"))
  98                return COLOR_CYAN;
  99        if (!strcasecmp(value, "white"))
 100                return COLOR_WHITE;
 101        die("bad config value '%s' for variable '%s'", value, var);
 102}
 103
 104int git_diff_config(const char *var, const char *value)
 105{
 106        if (!strcmp(var, "diff.renamelimit")) {
 107                diff_rename_limit_default = git_config_int(var, value);
 108                return 0;
 109        }
 110        if (!strcmp(var, "diff.color")) {
 111                if (!value)
 112                        diff_use_color_default = 1; /* bool */
 113                else if (!strcasecmp(value, "auto"))
 114                        diff_use_color_default = isatty(1);
 115                else if (!strcasecmp(value, "never"))
 116                        diff_use_color_default = 0;
 117                else if (!strcasecmp(value, "always"))
 118                        diff_use_color_default = 1;
 119                else
 120                        diff_use_color_default = git_config_bool(var, value);
 121                return 0;
 122        }
 123        if (!strncmp(var, "diff.color.", 11)) {
 124                int slot = parse_diff_color_slot(var, 11);
 125                diff_colors[slot] = parse_diff_color_value(value, var);
 126                return 0;
 127        }
 128        return git_default_config(var, value);
 129}
 130
 131static char *quote_one(const char *str)
 132{
 133        int needlen;
 134        char *xp;
 135
 136        if (!str)
 137                return NULL;
 138        needlen = quote_c_style(str, NULL, NULL, 0);
 139        if (!needlen)
 140                return strdup(str);
 141        xp = xmalloc(needlen + 1);
 142        quote_c_style(str, xp, NULL, 0);
 143        return xp;
 144}
 145
 146static char *quote_two(const char *one, const char *two)
 147{
 148        int need_one = quote_c_style(one, NULL, NULL, 1);
 149        int need_two = quote_c_style(two, NULL, NULL, 1);
 150        char *xp;
 151
 152        if (need_one + need_two) {
 153                if (!need_one) need_one = strlen(one);
 154                if (!need_two) need_one = strlen(two);
 155
 156                xp = xmalloc(need_one + need_two + 3);
 157                xp[0] = '"';
 158                quote_c_style(one, xp + 1, NULL, 1);
 159                quote_c_style(two, xp + need_one + 1, NULL, 1);
 160                strcpy(xp + need_one + need_two + 1, "\"");
 161                return xp;
 162        }
 163        need_one = strlen(one);
 164        need_two = strlen(two);
 165        xp = xmalloc(need_one + need_two + 1);
 166        strcpy(xp, one);
 167        strcpy(xp + need_one, two);
 168        return xp;
 169}
 170
 171static const char *external_diff(void)
 172{
 173        static const char *external_diff_cmd = NULL;
 174        static int done_preparing = 0;
 175
 176        if (done_preparing)
 177                return external_diff_cmd;
 178        external_diff_cmd = getenv("GIT_EXTERNAL_DIFF");
 179        done_preparing = 1;
 180        return external_diff_cmd;
 181}
 182
 183#define TEMPFILE_PATH_LEN               50
 184
 185static struct diff_tempfile {
 186        const char *name; /* filename external diff should read from */
 187        char hex[41];
 188        char mode[10];
 189        char tmp_path[TEMPFILE_PATH_LEN];
 190} diff_temp[2];
 191
 192static int count_lines(const char *data, int size)
 193{
 194        int count, ch, completely_empty = 1, nl_just_seen = 0;
 195        count = 0;
 196        while (0 < size--) {
 197                ch = *data++;
 198                if (ch == '\n') {
 199                        count++;
 200                        nl_just_seen = 1;
 201                        completely_empty = 0;
 202                }
 203                else {
 204                        nl_just_seen = 0;
 205                        completely_empty = 0;
 206                }
 207        }
 208        if (completely_empty)
 209                return 0;
 210        if (!nl_just_seen)
 211                count++; /* no trailing newline */
 212        return count;
 213}
 214
 215static void print_line_count(int count)
 216{
 217        switch (count) {
 218        case 0:
 219                printf("0,0");
 220                break;
 221        case 1:
 222                printf("1");
 223                break;
 224        default:
 225                printf("1,%d", count);
 226                break;
 227        }
 228}
 229
 230static void copy_file(int prefix, const char *data, int size)
 231{
 232        int ch, nl_just_seen = 1;
 233        while (0 < size--) {
 234                ch = *data++;
 235                if (nl_just_seen)
 236                        putchar(prefix);
 237                putchar(ch);
 238                if (ch == '\n')
 239                        nl_just_seen = 1;
 240                else
 241                        nl_just_seen = 0;
 242        }
 243        if (!nl_just_seen)
 244                printf("\n\\ No newline at end of file\n");
 245}
 246
 247static void emit_rewrite_diff(const char *name_a,
 248                              const char *name_b,
 249                              struct diff_filespec *one,
 250                              struct diff_filespec *two)
 251{
 252        int lc_a, lc_b;
 253        diff_populate_filespec(one, 0);
 254        diff_populate_filespec(two, 0);
 255        lc_a = count_lines(one->data, one->size);
 256        lc_b = count_lines(two->data, two->size);
 257        printf("--- %s\n+++ %s\n@@ -", name_a, name_b);
 258        print_line_count(lc_a);
 259        printf(" +");
 260        print_line_count(lc_b);
 261        printf(" @@\n");
 262        if (lc_a)
 263                copy_file('-', one->data, one->size);
 264        if (lc_b)
 265                copy_file('+', two->data, two->size);
 266}
 267
 268static int fill_mmfile(mmfile_t *mf, struct diff_filespec *one)
 269{
 270        if (!DIFF_FILE_VALID(one)) {
 271                mf->ptr = (char *)""; /* does not matter */
 272                mf->size = 0;
 273                return 0;
 274        }
 275        else if (diff_populate_filespec(one, 0))
 276                return -1;
 277        mf->ptr = one->data;
 278        mf->size = one->size;
 279        return 0;
 280}
 281
 282struct emit_callback {
 283        struct xdiff_emit_state xm;
 284        int nparents, color_diff;
 285        const char **label_path;
 286};
 287
 288static inline const char *get_color(int diff_use_color, enum color_diff ix)
 289{
 290        if (diff_use_color)
 291                return diff_colors[ix];
 292        return "";
 293}
 294
 295static void fn_out_consume(void *priv, char *line, unsigned long len)
 296{
 297        int i;
 298        struct emit_callback *ecbdata = priv;
 299        const char *set = get_color(ecbdata->color_diff, DIFF_METAINFO);
 300        const char *reset = get_color(ecbdata->color_diff, DIFF_RESET);
 301
 302        if (ecbdata->label_path[0]) {
 303                printf("%s--- %s%s\n", set, ecbdata->label_path[0], reset);
 304                printf("%s+++ %s%s\n", set, ecbdata->label_path[1], reset);
 305                ecbdata->label_path[0] = ecbdata->label_path[1] = NULL;
 306        }
 307
 308        /* This is not really necessary for now because
 309         * this codepath only deals with two-way diffs.
 310         */
 311        for (i = 0; i < len && line[i] == '@'; i++)
 312                ;
 313        if (2 <= i && i < len && line[i] == ' ') {
 314                ecbdata->nparents = i - 1;
 315                set = get_color(ecbdata->color_diff, DIFF_FRAGINFO);
 316        }
 317        else if (len < ecbdata->nparents)
 318                set = reset;
 319        else {
 320                int nparents = ecbdata->nparents;
 321                int color = DIFF_PLAIN;
 322                for (i = 0; i < nparents && len; i++) {
 323                        if (line[i] == '-')
 324                                color = DIFF_FILE_OLD;
 325                        else if (line[i] == '+')
 326                                color = DIFF_FILE_NEW;
 327                }
 328                set = get_color(ecbdata->color_diff, color);
 329        }
 330        if (len > 0 && line[len-1] == '\n')
 331                len--;
 332        printf("%s%.*s%s\n", set, (int) len, line, reset);
 333}
 334
 335static char *pprint_rename(const char *a, const char *b)
 336{
 337        const char *old = a;
 338        const char *new = b;
 339        char *name = NULL;
 340        int pfx_length, sfx_length;
 341        int len_a = strlen(a);
 342        int len_b = strlen(b);
 343
 344        /* Find common prefix */
 345        pfx_length = 0;
 346        while (*old && *new && *old == *new) {
 347                if (*old == '/')
 348                        pfx_length = old - a + 1;
 349                old++;
 350                new++;
 351        }
 352
 353        /* Find common suffix */
 354        old = a + len_a;
 355        new = b + len_b;
 356        sfx_length = 0;
 357        while (a <= old && b <= new && *old == *new) {
 358                if (*old == '/')
 359                        sfx_length = len_a - (old - a);
 360                old--;
 361                new--;
 362        }
 363
 364        /*
 365         * pfx{mid-a => mid-b}sfx
 366         * {pfx-a => pfx-b}sfx
 367         * pfx{sfx-a => sfx-b}
 368         * name-a => name-b
 369         */
 370        if (pfx_length + sfx_length) {
 371                int a_midlen = len_a - pfx_length - sfx_length;
 372                int b_midlen = len_b - pfx_length - sfx_length;
 373                if (a_midlen < 0) a_midlen = 0;
 374                if (b_midlen < 0) b_midlen = 0;
 375
 376                name = xmalloc(pfx_length + a_midlen + b_midlen + sfx_length + 7);
 377                sprintf(name, "%.*s{%.*s => %.*s}%s",
 378                        pfx_length, a,
 379                        a_midlen, a + pfx_length,
 380                        b_midlen, b + pfx_length,
 381                        a + len_a - sfx_length);
 382        }
 383        else {
 384                name = xmalloc(len_a + len_b + 5);
 385                sprintf(name, "%s => %s", a, b);
 386        }
 387        return name;
 388}
 389
 390struct diffstat_t {
 391        struct xdiff_emit_state xm;
 392
 393        int nr;
 394        int alloc;
 395        struct diffstat_file {
 396                char *name;
 397                unsigned is_unmerged:1;
 398                unsigned is_binary:1;
 399                unsigned is_renamed:1;
 400                unsigned int added, deleted;
 401        } **files;
 402};
 403
 404static struct diffstat_file *diffstat_add(struct diffstat_t *diffstat,
 405                                          const char *name_a,
 406                                          const char *name_b)
 407{
 408        struct diffstat_file *x;
 409        x = xcalloc(sizeof (*x), 1);
 410        if (diffstat->nr == diffstat->alloc) {
 411                diffstat->alloc = alloc_nr(diffstat->alloc);
 412                diffstat->files = xrealloc(diffstat->files,
 413                                diffstat->alloc * sizeof(x));
 414        }
 415        diffstat->files[diffstat->nr++] = x;
 416        if (name_b) {
 417                x->name = pprint_rename(name_a, name_b);
 418                x->is_renamed = 1;
 419        }
 420        else
 421                x->name = strdup(name_a);
 422        return x;
 423}
 424
 425static void diffstat_consume(void *priv, char *line, unsigned long len)
 426{
 427        struct diffstat_t *diffstat = priv;
 428        struct diffstat_file *x = diffstat->files[diffstat->nr - 1];
 429
 430        if (line[0] == '+')
 431                x->added++;
 432        else if (line[0] == '-')
 433                x->deleted++;
 434}
 435
 436static const char pluses[] = "++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++";
 437static const char minuses[]= "----------------------------------------------------------------------";
 438const char mime_boundary_leader[] = "------------";
 439
 440static void show_stats(struct diffstat_t* data)
 441{
 442        int i, len, add, del, total, adds = 0, dels = 0;
 443        int max, max_change = 0, max_len = 0;
 444        int total_files = data->nr;
 445
 446        if (data->nr == 0)
 447                return;
 448
 449        for (i = 0; i < data->nr; i++) {
 450                struct diffstat_file *file = data->files[i];
 451
 452                len = strlen(file->name);
 453                if (max_len < len)
 454                        max_len = len;
 455
 456                if (file->is_binary || file->is_unmerged)
 457                        continue;
 458                if (max_change < file->added + file->deleted)
 459                        max_change = file->added + file->deleted;
 460        }
 461
 462        for (i = 0; i < data->nr; i++) {
 463                const char *prefix = "";
 464                char *name = data->files[i]->name;
 465                int added = data->files[i]->added;
 466                int deleted = data->files[i]->deleted;
 467
 468                if (0 < (len = quote_c_style(name, NULL, NULL, 0))) {
 469                        char *qname = xmalloc(len + 1);
 470                        quote_c_style(name, qname, NULL, 0);
 471                        free(name);
 472                        data->files[i]->name = name = qname;
 473                }
 474
 475                /*
 476                 * "scale" the filename
 477                 */
 478                len = strlen(name);
 479                max = max_len;
 480                if (max > 50)
 481                        max = 50;
 482                if (len > max) {
 483                        char *slash;
 484                        prefix = "...";
 485                        max -= 3;
 486                        name += len - max;
 487                        slash = strchr(name, '/');
 488                        if (slash)
 489                                name = slash;
 490                }
 491                len = max;
 492
 493                /*
 494                 * scale the add/delete
 495                 */
 496                max = max_change;
 497                if (max + len > 70)
 498                        max = 70 - len;
 499
 500                if (data->files[i]->is_binary) {
 501                        printf(" %s%-*s |  Bin\n", prefix, len, name);
 502                        goto free_diffstat_file;
 503                }
 504                else if (data->files[i]->is_unmerged) {
 505                        printf(" %s%-*s |  Unmerged\n", prefix, len, name);
 506                        goto free_diffstat_file;
 507                }
 508                else if (!data->files[i]->is_renamed &&
 509                         (added + deleted == 0)) {
 510                        total_files--;
 511                        goto free_diffstat_file;
 512                }
 513
 514                add = added;
 515                del = deleted;
 516                total = add + del;
 517                adds += add;
 518                dels += del;
 519
 520                if (max_change > 0) {
 521                        total = (total * max + max_change / 2) / max_change;
 522                        add = (add * max + max_change / 2) / max_change;
 523                        del = total - add;
 524                }
 525                printf(" %s%-*s |%5d %.*s%.*s\n", prefix,
 526                                len, name, added + deleted,
 527                                add, pluses, del, minuses);
 528        free_diffstat_file:
 529                free(data->files[i]->name);
 530                free(data->files[i]);
 531        }
 532        free(data->files);
 533        printf(" %d files changed, %d insertions(+), %d deletions(-)\n",
 534                        total_files, adds, dels);
 535}
 536
 537struct checkdiff_t {
 538        struct xdiff_emit_state xm;
 539        const char *filename;
 540        int lineno;
 541};
 542
 543static void checkdiff_consume(void *priv, char *line, unsigned long len)
 544{
 545        struct checkdiff_t *data = priv;
 546
 547        if (line[0] == '+') {
 548                int i, spaces = 0;
 549
 550                data->lineno++;
 551
 552                /* check space before tab */
 553                for (i = 1; i < len && (line[i] == ' ' || line[i] == '\t'); i++)
 554                        if (line[i] == ' ')
 555                                spaces++;
 556                if (line[i - 1] == '\t' && spaces)
 557                        printf("%s:%d: space before tab:%.*s\n",
 558                                data->filename, data->lineno, (int)len, line);
 559
 560                /* check white space at line end */
 561                if (line[len - 1] == '\n')
 562                        len--;
 563                if (isspace(line[len - 1]))
 564                        printf("%s:%d: white space at end: %.*s\n",
 565                                data->filename, data->lineno, (int)len, line);
 566        } else if (line[0] == ' ')
 567                data->lineno++;
 568        else if (line[0] == '@') {
 569                char *plus = strchr(line, '+');
 570                if (plus)
 571                        data->lineno = strtol(plus, NULL, 10);
 572                else
 573                        die("invalid diff");
 574        }
 575}
 576
 577static unsigned char *deflate_it(char *data,
 578                                 unsigned long size,
 579                                 unsigned long *result_size)
 580{
 581        int bound;
 582        unsigned char *deflated;
 583        z_stream stream;
 584
 585        memset(&stream, 0, sizeof(stream));
 586        deflateInit(&stream, Z_BEST_COMPRESSION);
 587        bound = deflateBound(&stream, size);
 588        deflated = xmalloc(bound);
 589        stream.next_out = deflated;
 590        stream.avail_out = bound;
 591
 592        stream.next_in = (unsigned char *)data;
 593        stream.avail_in = size;
 594        while (deflate(&stream, Z_FINISH) == Z_OK)
 595                ; /* nothing */
 596        deflateEnd(&stream);
 597        *result_size = stream.total_out;
 598        return deflated;
 599}
 600
 601static void emit_binary_diff(mmfile_t *one, mmfile_t *two)
 602{
 603        void *cp;
 604        void *delta;
 605        void *deflated;
 606        void *data;
 607        unsigned long orig_size;
 608        unsigned long delta_size;
 609        unsigned long deflate_size;
 610        unsigned long data_size;
 611
 612        printf("GIT binary patch\n");
 613        /* We could do deflated delta, or we could do just deflated two,
 614         * whichever is smaller.
 615         */
 616        delta = NULL;
 617        deflated = deflate_it(two->ptr, two->size, &deflate_size);
 618        if (one->size && two->size) {
 619                delta = diff_delta(one->ptr, one->size,
 620                                   two->ptr, two->size,
 621                                   &delta_size, deflate_size);
 622                if (delta) {
 623                        void *to_free = delta;
 624                        orig_size = delta_size;
 625                        delta = deflate_it(delta, delta_size, &delta_size);
 626                        free(to_free);
 627                }
 628        }
 629
 630        if (delta && delta_size < deflate_size) {
 631                printf("delta %lu\n", orig_size);
 632                free(deflated);
 633                data = delta;
 634                data_size = delta_size;
 635        }
 636        else {
 637                printf("literal %lu\n", two->size);
 638                free(delta);
 639                data = deflated;
 640                data_size = deflate_size;
 641        }
 642
 643        /* emit data encoded in base85 */
 644        cp = data;
 645        while (data_size) {
 646                int bytes = (52 < data_size) ? 52 : data_size;
 647                char line[70];
 648                data_size -= bytes;
 649                if (bytes <= 26)
 650                        line[0] = bytes + 'A' - 1;
 651                else
 652                        line[0] = bytes - 26 + 'a' - 1;
 653                encode_85(line + 1, cp, bytes);
 654                cp = (char *) cp + bytes;
 655                puts(line);
 656        }
 657        printf("\n");
 658        free(data);
 659}
 660
 661#define FIRST_FEW_BYTES 8000
 662static int mmfile_is_binary(mmfile_t *mf)
 663{
 664        long sz = mf->size;
 665        if (FIRST_FEW_BYTES < sz)
 666                sz = FIRST_FEW_BYTES;
 667        if (memchr(mf->ptr, 0, sz))
 668                return 1;
 669        return 0;
 670}
 671
 672static void builtin_diff(const char *name_a,
 673                         const char *name_b,
 674                         struct diff_filespec *one,
 675                         struct diff_filespec *two,
 676                         const char *xfrm_msg,
 677                         struct diff_options *o,
 678                         int complete_rewrite)
 679{
 680        mmfile_t mf1, mf2;
 681        const char *lbl[2];
 682        char *a_one, *b_two;
 683        const char *set = get_color(o->color_diff, DIFF_METAINFO);
 684        const char *reset = get_color(o->color_diff, DIFF_RESET);
 685
 686        a_one = quote_two("a/", name_a);
 687        b_two = quote_two("b/", name_b);
 688        lbl[0] = DIFF_FILE_VALID(one) ? a_one : "/dev/null";
 689        lbl[1] = DIFF_FILE_VALID(two) ? b_two : "/dev/null";
 690        printf("%sdiff --git %s %s%s\n", set, a_one, b_two, reset);
 691        if (lbl[0][0] == '/') {
 692                /* /dev/null */
 693                printf("%snew file mode %06o%s\n", set, two->mode, reset);
 694                if (xfrm_msg && xfrm_msg[0])
 695                        printf("%s%s%s\n", set, xfrm_msg, reset);
 696        }
 697        else if (lbl[1][0] == '/') {
 698                printf("%sdeleted file mode %06o%s\n", set, one->mode, reset);
 699                if (xfrm_msg && xfrm_msg[0])
 700                        printf("%s%s%s\n", set, xfrm_msg, reset);
 701        }
 702        else {
 703                if (one->mode != two->mode) {
 704                        printf("%sold mode %06o%s\n", set, one->mode, reset);
 705                        printf("%snew mode %06o%s\n", set, two->mode, reset);
 706                }
 707                if (xfrm_msg && xfrm_msg[0])
 708                        printf("%s%s%s\n", set, xfrm_msg, reset);
 709                /*
 710                 * we do not run diff between different kind
 711                 * of objects.
 712                 */
 713                if ((one->mode ^ two->mode) & S_IFMT)
 714                        goto free_ab_and_return;
 715                if (complete_rewrite) {
 716                        emit_rewrite_diff(name_a, name_b, one, two);
 717                        goto free_ab_and_return;
 718                }
 719        }
 720
 721        if (fill_mmfile(&mf1, one) < 0 || fill_mmfile(&mf2, two) < 0)
 722                die("unable to read files to diff");
 723
 724        if (mmfile_is_binary(&mf1) || mmfile_is_binary(&mf2)) {
 725                /* Quite common confusing case */
 726                if (mf1.size == mf2.size &&
 727                    !memcmp(mf1.ptr, mf2.ptr, mf1.size))
 728                        goto free_ab_and_return;
 729                if (o->binary)
 730                        emit_binary_diff(&mf1, &mf2);
 731                else
 732                        printf("Binary files %s and %s differ\n",
 733                               lbl[0], lbl[1]);
 734        }
 735        else {
 736                /* Crazy xdl interfaces.. */
 737                const char *diffopts = getenv("GIT_DIFF_OPTS");
 738                xpparam_t xpp;
 739                xdemitconf_t xecfg;
 740                xdemitcb_t ecb;
 741                struct emit_callback ecbdata;
 742
 743                memset(&ecbdata, 0, sizeof(ecbdata));
 744                ecbdata.label_path = lbl;
 745                ecbdata.color_diff = o->color_diff;
 746                xpp.flags = XDF_NEED_MINIMAL;
 747                xecfg.ctxlen = o->context;
 748                xecfg.flags = XDL_EMIT_FUNCNAMES;
 749                if (!diffopts)
 750                        ;
 751                else if (!strncmp(diffopts, "--unified=", 10))
 752                        xecfg.ctxlen = strtoul(diffopts + 10, NULL, 10);
 753                else if (!strncmp(diffopts, "-u", 2))
 754                        xecfg.ctxlen = strtoul(diffopts + 2, NULL, 10);
 755                ecb.outf = xdiff_outf;
 756                ecb.priv = &ecbdata;
 757                ecbdata.xm.consume = fn_out_consume;
 758                xdl_diff(&mf1, &mf2, &xpp, &xecfg, &ecb);
 759        }
 760
 761 free_ab_and_return:
 762        free(a_one);
 763        free(b_two);
 764        return;
 765}
 766
 767static void builtin_diffstat(const char *name_a, const char *name_b,
 768                             struct diff_filespec *one,
 769                             struct diff_filespec *two,
 770                             struct diffstat_t *diffstat,
 771                             int complete_rewrite)
 772{
 773        mmfile_t mf1, mf2;
 774        struct diffstat_file *data;
 775
 776        data = diffstat_add(diffstat, name_a, name_b);
 777
 778        if (!one || !two) {
 779                data->is_unmerged = 1;
 780                return;
 781        }
 782        if (complete_rewrite) {
 783                diff_populate_filespec(one, 0);
 784                diff_populate_filespec(two, 0);
 785                data->deleted = count_lines(one->data, one->size);
 786                data->added = count_lines(two->data, two->size);
 787                return;
 788        }
 789        if (fill_mmfile(&mf1, one) < 0 || fill_mmfile(&mf2, two) < 0)
 790                die("unable to read files to diff");
 791
 792        if (mmfile_is_binary(&mf1) || mmfile_is_binary(&mf2))
 793                data->is_binary = 1;
 794        else {
 795                /* Crazy xdl interfaces.. */
 796                xpparam_t xpp;
 797                xdemitconf_t xecfg;
 798                xdemitcb_t ecb;
 799
 800                xpp.flags = XDF_NEED_MINIMAL;
 801                xecfg.ctxlen = 0;
 802                xecfg.flags = 0;
 803                ecb.outf = xdiff_outf;
 804                ecb.priv = diffstat;
 805                xdl_diff(&mf1, &mf2, &xpp, &xecfg, &ecb);
 806        }
 807}
 808
 809static void builtin_checkdiff(const char *name_a, const char *name_b,
 810                             struct diff_filespec *one,
 811                             struct diff_filespec *two)
 812{
 813        mmfile_t mf1, mf2;
 814        struct checkdiff_t data;
 815
 816        if (!two)
 817                return;
 818
 819        memset(&data, 0, sizeof(data));
 820        data.xm.consume = checkdiff_consume;
 821        data.filename = name_b ? name_b : name_a;
 822        data.lineno = 0;
 823
 824        if (fill_mmfile(&mf1, one) < 0 || fill_mmfile(&mf2, two) < 0)
 825                die("unable to read files to diff");
 826
 827        if (mmfile_is_binary(&mf2))
 828                return;
 829        else {
 830                /* Crazy xdl interfaces.. */
 831                xpparam_t xpp;
 832                xdemitconf_t xecfg;
 833                xdemitcb_t ecb;
 834
 835                xpp.flags = XDF_NEED_MINIMAL;
 836                xecfg.ctxlen = 0;
 837                xecfg.flags = 0;
 838                ecb.outf = xdiff_outf;
 839                ecb.priv = &data;
 840                xdl_diff(&mf1, &mf2, &xpp, &xecfg, &ecb);
 841        }
 842}
 843
 844struct diff_filespec *alloc_filespec(const char *path)
 845{
 846        int namelen = strlen(path);
 847        struct diff_filespec *spec = xmalloc(sizeof(*spec) + namelen + 1);
 848
 849        memset(spec, 0, sizeof(*spec));
 850        spec->path = (char *)(spec + 1);
 851        memcpy(spec->path, path, namelen+1);
 852        return spec;
 853}
 854
 855void fill_filespec(struct diff_filespec *spec, const unsigned char *sha1,
 856                   unsigned short mode)
 857{
 858        if (mode) {
 859                spec->mode = canon_mode(mode);
 860                memcpy(spec->sha1, sha1, 20);
 861                spec->sha1_valid = !!memcmp(sha1, null_sha1, 20);
 862        }
 863}
 864
 865/*
 866 * Given a name and sha1 pair, if the dircache tells us the file in
 867 * the work tree has that object contents, return true, so that
 868 * prepare_temp_file() does not have to inflate and extract.
 869 */
 870static int work_tree_matches(const char *name, const unsigned char *sha1)
 871{
 872        struct cache_entry *ce;
 873        struct stat st;
 874        int pos, len;
 875
 876        /* We do not read the cache ourselves here, because the
 877         * benchmark with my previous version that always reads cache
 878         * shows that it makes things worse for diff-tree comparing
 879         * two linux-2.6 kernel trees in an already checked out work
 880         * tree.  This is because most diff-tree comparisons deal with
 881         * only a small number of files, while reading the cache is
 882         * expensive for a large project, and its cost outweighs the
 883         * savings we get by not inflating the object to a temporary
 884         * file.  Practically, this code only helps when we are used
 885         * by diff-cache --cached, which does read the cache before
 886         * calling us.
 887         */
 888        if (!active_cache)
 889                return 0;
 890
 891        len = strlen(name);
 892        pos = cache_name_pos(name, len);
 893        if (pos < 0)
 894                return 0;
 895        ce = active_cache[pos];
 896        if ((lstat(name, &st) < 0) ||
 897            !S_ISREG(st.st_mode) || /* careful! */
 898            ce_match_stat(ce, &st, 0) ||
 899            memcmp(sha1, ce->sha1, 20))
 900                return 0;
 901        /* we return 1 only when we can stat, it is a regular file,
 902         * stat information matches, and sha1 recorded in the cache
 903         * matches.  I.e. we know the file in the work tree really is
 904         * the same as the <name, sha1> pair.
 905         */
 906        return 1;
 907}
 908
 909static struct sha1_size_cache {
 910        unsigned char sha1[20];
 911        unsigned long size;
 912} **sha1_size_cache;
 913static int sha1_size_cache_nr, sha1_size_cache_alloc;
 914
 915static struct sha1_size_cache *locate_size_cache(unsigned char *sha1,
 916                                                 int find_only,
 917                                                 unsigned long size)
 918{
 919        int first, last;
 920        struct sha1_size_cache *e;
 921
 922        first = 0;
 923        last = sha1_size_cache_nr;
 924        while (last > first) {
 925                int cmp, next = (last + first) >> 1;
 926                e = sha1_size_cache[next];
 927                cmp = memcmp(e->sha1, sha1, 20);
 928                if (!cmp)
 929                        return e;
 930                if (cmp < 0) {
 931                        last = next;
 932                        continue;
 933                }
 934                first = next+1;
 935        }
 936        /* not found */
 937        if (find_only)
 938                return NULL;
 939        /* insert to make it at "first" */
 940        if (sha1_size_cache_alloc <= sha1_size_cache_nr) {
 941                sha1_size_cache_alloc = alloc_nr(sha1_size_cache_alloc);
 942                sha1_size_cache = xrealloc(sha1_size_cache,
 943                                           sha1_size_cache_alloc *
 944                                           sizeof(*sha1_size_cache));
 945        }
 946        sha1_size_cache_nr++;
 947        if (first < sha1_size_cache_nr)
 948                memmove(sha1_size_cache + first + 1, sha1_size_cache + first,
 949                        (sha1_size_cache_nr - first - 1) *
 950                        sizeof(*sha1_size_cache));
 951        e = xmalloc(sizeof(struct sha1_size_cache));
 952        sha1_size_cache[first] = e;
 953        memcpy(e->sha1, sha1, 20);
 954        e->size = size;
 955        return e;
 956}
 957
 958/*
 959 * While doing rename detection and pickaxe operation, we may need to
 960 * grab the data for the blob (or file) for our own in-core comparison.
 961 * diff_filespec has data and size fields for this purpose.
 962 */
 963int diff_populate_filespec(struct diff_filespec *s, int size_only)
 964{
 965        int err = 0;
 966        if (!DIFF_FILE_VALID(s))
 967                die("internal error: asking to populate invalid file.");
 968        if (S_ISDIR(s->mode))
 969                return -1;
 970
 971        if (!use_size_cache)
 972                size_only = 0;
 973
 974        if (s->data)
 975                return err;
 976        if (!s->sha1_valid ||
 977            work_tree_matches(s->path, s->sha1)) {
 978                struct stat st;
 979                int fd;
 980                if (lstat(s->path, &st) < 0) {
 981                        if (errno == ENOENT) {
 982                        err_empty:
 983                                err = -1;
 984                        empty:
 985                                s->data = (char *)"";
 986                                s->size = 0;
 987                                return err;
 988                        }
 989                }
 990                s->size = st.st_size;
 991                if (!s->size)
 992                        goto empty;
 993                if (size_only)
 994                        return 0;
 995                if (S_ISLNK(st.st_mode)) {
 996                        int ret;
 997                        s->data = xmalloc(s->size);
 998                        s->should_free = 1;
 999                        ret = readlink(s->path, s->data, s->size);
1000                        if (ret < 0) {
1001                                free(s->data);
1002                                goto err_empty;
1003                        }
1004                        return 0;
1005                }
1006                fd = open(s->path, O_RDONLY);
1007                if (fd < 0)
1008                        goto err_empty;
1009                s->data = mmap(NULL, s->size, PROT_READ, MAP_PRIVATE, fd, 0);
1010                close(fd);
1011                if (s->data == MAP_FAILED)
1012                        goto err_empty;
1013                s->should_munmap = 1;
1014        }
1015        else {
1016                char type[20];
1017                struct sha1_size_cache *e;
1018
1019                if (size_only) {
1020                        e = locate_size_cache(s->sha1, 1, 0);
1021                        if (e) {
1022                                s->size = e->size;
1023                                return 0;
1024                        }
1025                        if (!sha1_object_info(s->sha1, type, &s->size))
1026                                locate_size_cache(s->sha1, 0, s->size);
1027                }
1028                else {
1029                        s->data = read_sha1_file(s->sha1, type, &s->size);
1030                        s->should_free = 1;
1031                }
1032        }
1033        return 0;
1034}
1035
1036void diff_free_filespec_data(struct diff_filespec *s)
1037{
1038        if (s->should_free)
1039                free(s->data);
1040        else if (s->should_munmap)
1041                munmap(s->data, s->size);
1042        s->should_free = s->should_munmap = 0;
1043        s->data = NULL;
1044        free(s->cnt_data);
1045        s->cnt_data = NULL;
1046}
1047
1048static void prep_temp_blob(struct diff_tempfile *temp,
1049                           void *blob,
1050                           unsigned long size,
1051                           const unsigned char *sha1,
1052                           int mode)
1053{
1054        int fd;
1055
1056        fd = git_mkstemp(temp->tmp_path, TEMPFILE_PATH_LEN, ".diff_XXXXXX");
1057        if (fd < 0)
1058                die("unable to create temp-file");
1059        if (write(fd, blob, size) != size)
1060                die("unable to write temp-file");
1061        close(fd);
1062        temp->name = temp->tmp_path;
1063        strcpy(temp->hex, sha1_to_hex(sha1));
1064        temp->hex[40] = 0;
1065        sprintf(temp->mode, "%06o", mode);
1066}
1067
1068static void prepare_temp_file(const char *name,
1069                              struct diff_tempfile *temp,
1070                              struct diff_filespec *one)
1071{
1072        if (!DIFF_FILE_VALID(one)) {
1073        not_a_valid_file:
1074                /* A '-' entry produces this for file-2, and
1075                 * a '+' entry produces this for file-1.
1076                 */
1077                temp->name = "/dev/null";
1078                strcpy(temp->hex, ".");
1079                strcpy(temp->mode, ".");
1080                return;
1081        }
1082
1083        if (!one->sha1_valid ||
1084            work_tree_matches(name, one->sha1)) {
1085                struct stat st;
1086                if (lstat(name, &st) < 0) {
1087                        if (errno == ENOENT)
1088                                goto not_a_valid_file;
1089                        die("stat(%s): %s", name, strerror(errno));
1090                }
1091                if (S_ISLNK(st.st_mode)) {
1092                        int ret;
1093                        char buf[PATH_MAX + 1]; /* ought to be SYMLINK_MAX */
1094                        if (sizeof(buf) <= st.st_size)
1095                                die("symlink too long: %s", name);
1096                        ret = readlink(name, buf, st.st_size);
1097                        if (ret < 0)
1098                                die("readlink(%s)", name);
1099                        prep_temp_blob(temp, buf, st.st_size,
1100                                       (one->sha1_valid ?
1101                                        one->sha1 : null_sha1),
1102                                       (one->sha1_valid ?
1103                                        one->mode : S_IFLNK));
1104                }
1105                else {
1106                        /* we can borrow from the file in the work tree */
1107                        temp->name = name;
1108                        if (!one->sha1_valid)
1109                                strcpy(temp->hex, sha1_to_hex(null_sha1));
1110                        else
1111                                strcpy(temp->hex, sha1_to_hex(one->sha1));
1112                        /* Even though we may sometimes borrow the
1113                         * contents from the work tree, we always want
1114                         * one->mode.  mode is trustworthy even when
1115                         * !(one->sha1_valid), as long as
1116                         * DIFF_FILE_VALID(one).
1117                         */
1118                        sprintf(temp->mode, "%06o", one->mode);
1119                }
1120                return;
1121        }
1122        else {
1123                if (diff_populate_filespec(one, 0))
1124                        die("cannot read data blob for %s", one->path);
1125                prep_temp_blob(temp, one->data, one->size,
1126                               one->sha1, one->mode);
1127        }
1128}
1129
1130static void remove_tempfile(void)
1131{
1132        int i;
1133
1134        for (i = 0; i < 2; i++)
1135                if (diff_temp[i].name == diff_temp[i].tmp_path) {
1136                        unlink(diff_temp[i].name);
1137                        diff_temp[i].name = NULL;
1138                }
1139}
1140
1141static void remove_tempfile_on_signal(int signo)
1142{
1143        remove_tempfile();
1144        signal(SIGINT, SIG_DFL);
1145        raise(signo);
1146}
1147
1148static int spawn_prog(const char *pgm, const char **arg)
1149{
1150        pid_t pid;
1151        int status;
1152
1153        fflush(NULL);
1154        pid = fork();
1155        if (pid < 0)
1156                die("unable to fork");
1157        if (!pid) {
1158                execvp(pgm, (char *const*) arg);
1159                exit(255);
1160        }
1161
1162        while (waitpid(pid, &status, 0) < 0) {
1163                if (errno == EINTR)
1164                        continue;
1165                return -1;
1166        }
1167
1168        /* Earlier we did not check the exit status because
1169         * diff exits non-zero if files are different, and
1170         * we are not interested in knowing that.  It was a
1171         * mistake which made it harder to quit a diff-*
1172         * session that uses the git-apply-patch-script as
1173         * the GIT_EXTERNAL_DIFF.  A custom GIT_EXTERNAL_DIFF
1174         * should also exit non-zero only when it wants to
1175         * abort the entire diff-* session.
1176         */
1177        if (WIFEXITED(status) && !WEXITSTATUS(status))
1178                return 0;
1179        return -1;
1180}
1181
1182/* An external diff command takes:
1183 *
1184 * diff-cmd name infile1 infile1-sha1 infile1-mode \
1185 *               infile2 infile2-sha1 infile2-mode [ rename-to ]
1186 *
1187 */
1188static void run_external_diff(const char *pgm,
1189                              const char *name,
1190                              const char *other,
1191                              struct diff_filespec *one,
1192                              struct diff_filespec *two,
1193                              const char *xfrm_msg,
1194                              int complete_rewrite)
1195{
1196        const char *spawn_arg[10];
1197        struct diff_tempfile *temp = diff_temp;
1198        int retval;
1199        static int atexit_asked = 0;
1200        const char *othername;
1201        const char **arg = &spawn_arg[0];
1202
1203        othername = (other? other : name);
1204        if (one && two) {
1205                prepare_temp_file(name, &temp[0], one);
1206                prepare_temp_file(othername, &temp[1], two);
1207                if (! atexit_asked &&
1208                    (temp[0].name == temp[0].tmp_path ||
1209                     temp[1].name == temp[1].tmp_path)) {
1210                        atexit_asked = 1;
1211                        atexit(remove_tempfile);
1212                }
1213                signal(SIGINT, remove_tempfile_on_signal);
1214        }
1215
1216        if (one && two) {
1217                *arg++ = pgm;
1218                *arg++ = name;
1219                *arg++ = temp[0].name;
1220                *arg++ = temp[0].hex;
1221                *arg++ = temp[0].mode;
1222                *arg++ = temp[1].name;
1223                *arg++ = temp[1].hex;
1224                *arg++ = temp[1].mode;
1225                if (other) {
1226                        *arg++ = other;
1227                        *arg++ = xfrm_msg;
1228                }
1229        } else {
1230                *arg++ = pgm;
1231                *arg++ = name;
1232        }
1233        *arg = NULL;
1234        retval = spawn_prog(pgm, spawn_arg);
1235        remove_tempfile();
1236        if (retval) {
1237                fprintf(stderr, "external diff died, stopping at %s.\n", name);
1238                exit(1);
1239        }
1240}
1241
1242static void run_diff_cmd(const char *pgm,
1243                         const char *name,
1244                         const char *other,
1245                         struct diff_filespec *one,
1246                         struct diff_filespec *two,
1247                         const char *xfrm_msg,
1248                         struct diff_options *o,
1249                         int complete_rewrite)
1250{
1251        if (pgm) {
1252                run_external_diff(pgm, name, other, one, two, xfrm_msg,
1253                                  complete_rewrite);
1254                return;
1255        }
1256        if (one && two)
1257                builtin_diff(name, other ? other : name,
1258                             one, two, xfrm_msg, o, complete_rewrite);
1259        else
1260                printf("* Unmerged path %s\n", name);
1261}
1262
1263static void diff_fill_sha1_info(struct diff_filespec *one)
1264{
1265        if (DIFF_FILE_VALID(one)) {
1266                if (!one->sha1_valid) {
1267                        struct stat st;
1268                        if (lstat(one->path, &st) < 0)
1269                                die("stat %s", one->path);
1270                        if (index_path(one->sha1, one->path, &st, 0))
1271                                die("cannot hash %s\n", one->path);
1272                }
1273        }
1274        else
1275                memset(one->sha1, 0, 20);
1276}
1277
1278static void run_diff(struct diff_filepair *p, struct diff_options *o)
1279{
1280        const char *pgm = external_diff();
1281        char msg[PATH_MAX*2+300], *xfrm_msg;
1282        struct diff_filespec *one;
1283        struct diff_filespec *two;
1284        const char *name;
1285        const char *other;
1286        char *name_munged, *other_munged;
1287        int complete_rewrite = 0;
1288        int len;
1289
1290        if (DIFF_PAIR_UNMERGED(p)) {
1291                /* unmerged */
1292                run_diff_cmd(pgm, p->one->path, NULL, NULL, NULL, NULL, o, 0);
1293                return;
1294        }
1295
1296        name = p->one->path;
1297        other = (strcmp(name, p->two->path) ? p->two->path : NULL);
1298        name_munged = quote_one(name);
1299        other_munged = quote_one(other);
1300        one = p->one; two = p->two;
1301
1302        diff_fill_sha1_info(one);
1303        diff_fill_sha1_info(two);
1304
1305        len = 0;
1306        switch (p->status) {
1307        case DIFF_STATUS_COPIED:
1308                len += snprintf(msg + len, sizeof(msg) - len,
1309                                "similarity index %d%%\n"
1310                                "copy from %s\n"
1311                                "copy to %s\n",
1312                                (int)(0.5 + p->score * 100.0/MAX_SCORE),
1313                                name_munged, other_munged);
1314                break;
1315        case DIFF_STATUS_RENAMED:
1316                len += snprintf(msg + len, sizeof(msg) - len,
1317                                "similarity index %d%%\n"
1318                                "rename from %s\n"
1319                                "rename to %s\n",
1320                                (int)(0.5 + p->score * 100.0/MAX_SCORE),
1321                                name_munged, other_munged);
1322                break;
1323        case DIFF_STATUS_MODIFIED:
1324                if (p->score) {
1325                        len += snprintf(msg + len, sizeof(msg) - len,
1326                                        "dissimilarity index %d%%\n",
1327                                        (int)(0.5 + p->score *
1328                                              100.0/MAX_SCORE));
1329                        complete_rewrite = 1;
1330                        break;
1331                }
1332                /* fallthru */
1333        default:
1334                /* nothing */
1335                ;
1336        }
1337
1338        if (memcmp(one->sha1, two->sha1, 20)) {
1339                int abbrev = o->full_index ? 40 : DEFAULT_ABBREV;
1340
1341                len += snprintf(msg + len, sizeof(msg) - len,
1342                                "index %.*s..%.*s",
1343                                abbrev, sha1_to_hex(one->sha1),
1344                                abbrev, sha1_to_hex(two->sha1));
1345                if (one->mode == two->mode)
1346                        len += snprintf(msg + len, sizeof(msg) - len,
1347                                        " %06o", one->mode);
1348                len += snprintf(msg + len, sizeof(msg) - len, "\n");
1349        }
1350
1351        if (len)
1352                msg[--len] = 0;
1353        xfrm_msg = len ? msg : NULL;
1354
1355        if (!pgm &&
1356            DIFF_FILE_VALID(one) && DIFF_FILE_VALID(two) &&
1357            (S_IFMT & one->mode) != (S_IFMT & two->mode)) {
1358                /* a filepair that changes between file and symlink
1359                 * needs to be split into deletion and creation.
1360                 */
1361                struct diff_filespec *null = alloc_filespec(two->path);
1362                run_diff_cmd(NULL, name, other, one, null, xfrm_msg, o, 0);
1363                free(null);
1364                null = alloc_filespec(one->path);
1365                run_diff_cmd(NULL, name, other, null, two, xfrm_msg, o, 0);
1366                free(null);
1367        }
1368        else
1369                run_diff_cmd(pgm, name, other, one, two, xfrm_msg, o,
1370                             complete_rewrite);
1371
1372        free(name_munged);
1373        free(other_munged);
1374}
1375
1376static void run_diffstat(struct diff_filepair *p, struct diff_options *o,
1377                         struct diffstat_t *diffstat)
1378{
1379        const char *name;
1380        const char *other;
1381        int complete_rewrite = 0;
1382
1383        if (DIFF_PAIR_UNMERGED(p)) {
1384                /* unmerged */
1385                builtin_diffstat(p->one->path, NULL, NULL, NULL, diffstat, 0);
1386                return;
1387        }
1388
1389        name = p->one->path;
1390        other = (strcmp(name, p->two->path) ? p->two->path : NULL);
1391
1392        diff_fill_sha1_info(p->one);
1393        diff_fill_sha1_info(p->two);
1394
1395        if (p->status == DIFF_STATUS_MODIFIED && p->score)
1396                complete_rewrite = 1;
1397        builtin_diffstat(name, other, p->one, p->two, diffstat, complete_rewrite);
1398}
1399
1400static void run_checkdiff(struct diff_filepair *p, struct diff_options *o)
1401{
1402        const char *name;
1403        const char *other;
1404
1405        if (DIFF_PAIR_UNMERGED(p)) {
1406                /* unmerged */
1407                return;
1408        }
1409
1410        name = p->one->path;
1411        other = (strcmp(name, p->two->path) ? p->two->path : NULL);
1412
1413        diff_fill_sha1_info(p->one);
1414        diff_fill_sha1_info(p->two);
1415
1416        builtin_checkdiff(name, other, p->one, p->two);
1417}
1418
1419void diff_setup(struct diff_options *options)
1420{
1421        memset(options, 0, sizeof(*options));
1422        options->output_format = DIFF_FORMAT_RAW;
1423        options->line_termination = '\n';
1424        options->break_opt = -1;
1425        options->rename_limit = -1;
1426        options->context = 3;
1427
1428        options->change = diff_change;
1429        options->add_remove = diff_addremove;
1430        options->color_diff = diff_use_color_default;
1431}
1432
1433int diff_setup_done(struct diff_options *options)
1434{
1435        if ((options->find_copies_harder &&
1436             options->detect_rename != DIFF_DETECT_COPY) ||
1437            (0 <= options->rename_limit && !options->detect_rename))
1438                return -1;
1439
1440        /*
1441         * These cases always need recursive; we do not drop caller-supplied
1442         * recursive bits for other formats here.
1443         */
1444        if ((options->output_format == DIFF_FORMAT_PATCH) ||
1445            (options->output_format == DIFF_FORMAT_DIFFSTAT) ||
1446            (options->output_format == DIFF_FORMAT_CHECKDIFF))
1447                options->recursive = 1;
1448
1449        /*
1450         * These combinations do not make sense.
1451         */
1452        if (options->output_format == DIFF_FORMAT_RAW)
1453                options->with_raw = 0;
1454        if (options->output_format == DIFF_FORMAT_DIFFSTAT)
1455                options->with_stat  = 0;
1456
1457        if (options->detect_rename && options->rename_limit < 0)
1458                options->rename_limit = diff_rename_limit_default;
1459        if (options->setup & DIFF_SETUP_USE_CACHE) {
1460                if (!active_cache)
1461                        /* read-cache does not die even when it fails
1462                         * so it is safe for us to do this here.  Also
1463                         * it does not smudge active_cache or active_nr
1464                         * when it fails, so we do not have to worry about
1465                         * cleaning it up ourselves either.
1466                         */
1467                        read_cache();
1468        }
1469        if (options->setup & DIFF_SETUP_USE_SIZE_CACHE)
1470                use_size_cache = 1;
1471        if (options->abbrev <= 0 || 40 < options->abbrev)
1472                options->abbrev = 40; /* full */
1473
1474        return 0;
1475}
1476
1477static int opt_arg(const char *arg, int arg_short, const char *arg_long, int *val)
1478{
1479        char c, *eq;
1480        int len;
1481
1482        if (*arg != '-')
1483                return 0;
1484        c = *++arg;
1485        if (!c)
1486                return 0;
1487        if (c == arg_short) {
1488                c = *++arg;
1489                if (!c)
1490                        return 1;
1491                if (val && isdigit(c)) {
1492                        char *end;
1493                        int n = strtoul(arg, &end, 10);
1494                        if (*end)
1495                                return 0;
1496                        *val = n;
1497                        return 1;
1498                }
1499                return 0;
1500        }
1501        if (c != '-')
1502                return 0;
1503        arg++;
1504        eq = strchr(arg, '=');
1505        if (eq)
1506                len = eq - arg;
1507        else
1508                len = strlen(arg);
1509        if (!len || strncmp(arg, arg_long, len))
1510                return 0;
1511        if (eq) {
1512                int n;
1513                char *end;
1514                if (!isdigit(*++eq))
1515                        return 0;
1516                n = strtoul(eq, &end, 10);
1517                if (*end)
1518                        return 0;
1519                *val = n;
1520        }
1521        return 1;
1522}
1523
1524int diff_opt_parse(struct diff_options *options, const char **av, int ac)
1525{
1526        const char *arg = av[0];
1527        if (!strcmp(arg, "-p") || !strcmp(arg, "-u"))
1528                options->output_format = DIFF_FORMAT_PATCH;
1529        else if (opt_arg(arg, 'U', "unified", &options->context))
1530                options->output_format = DIFF_FORMAT_PATCH;
1531        else if (!strcmp(arg, "--patch-with-raw")) {
1532                options->output_format = DIFF_FORMAT_PATCH;
1533                options->with_raw = 1;
1534        }
1535        else if (!strcmp(arg, "--stat"))
1536                options->output_format = DIFF_FORMAT_DIFFSTAT;
1537        else if (!strcmp(arg, "--check"))
1538                options->output_format = DIFF_FORMAT_CHECKDIFF;
1539        else if (!strcmp(arg, "--summary"))
1540                options->summary = 1;
1541        else if (!strcmp(arg, "--patch-with-stat")) {
1542                options->output_format = DIFF_FORMAT_PATCH;
1543                options->with_stat = 1;
1544        }
1545        else if (!strcmp(arg, "-z"))
1546                options->line_termination = 0;
1547        else if (!strncmp(arg, "-l", 2))
1548                options->rename_limit = strtoul(arg+2, NULL, 10);
1549        else if (!strcmp(arg, "--full-index"))
1550                options->full_index = 1;
1551        else if (!strcmp(arg, "--binary")) {
1552                options->output_format = DIFF_FORMAT_PATCH;
1553                options->full_index = options->binary = 1;
1554        }
1555        else if (!strcmp(arg, "--name-only"))
1556                options->output_format = DIFF_FORMAT_NAME;
1557        else if (!strcmp(arg, "--name-status"))
1558                options->output_format = DIFF_FORMAT_NAME_STATUS;
1559        else if (!strcmp(arg, "-R"))
1560                options->reverse_diff = 1;
1561        else if (!strncmp(arg, "-S", 2))
1562                options->pickaxe = arg + 2;
1563        else if (!strcmp(arg, "-s"))
1564                options->output_format = DIFF_FORMAT_NO_OUTPUT;
1565        else if (!strncmp(arg, "-O", 2))
1566                options->orderfile = arg + 2;
1567        else if (!strncmp(arg, "--diff-filter=", 14))
1568                options->filter = arg + 14;
1569        else if (!strcmp(arg, "--pickaxe-all"))
1570                options->pickaxe_opts = DIFF_PICKAXE_ALL;
1571        else if (!strcmp(arg, "--pickaxe-regex"))
1572                options->pickaxe_opts = DIFF_PICKAXE_REGEX;
1573        else if (!strncmp(arg, "-B", 2)) {
1574                if ((options->break_opt =
1575                     diff_scoreopt_parse(arg)) == -1)
1576                        return -1;
1577        }
1578        else if (!strncmp(arg, "-M", 2)) {
1579                if ((options->rename_score =
1580                     diff_scoreopt_parse(arg)) == -1)
1581                        return -1;
1582                options->detect_rename = DIFF_DETECT_RENAME;
1583        }
1584        else if (!strncmp(arg, "-C", 2)) {
1585                if ((options->rename_score =
1586                     diff_scoreopt_parse(arg)) == -1)
1587                        return -1;
1588                options->detect_rename = DIFF_DETECT_COPY;
1589        }
1590        else if (!strcmp(arg, "--find-copies-harder"))
1591                options->find_copies_harder = 1;
1592        else if (!strcmp(arg, "--abbrev"))
1593                options->abbrev = DEFAULT_ABBREV;
1594        else if (!strncmp(arg, "--abbrev=", 9)) {
1595                options->abbrev = strtoul(arg + 9, NULL, 10);
1596                if (options->abbrev < MINIMUM_ABBREV)
1597                        options->abbrev = MINIMUM_ABBREV;
1598                else if (40 < options->abbrev)
1599                        options->abbrev = 40;
1600        }
1601        else if (!strcmp(arg, "--color"))
1602                options->color_diff = 1;
1603        else
1604                return 0;
1605        return 1;
1606}
1607
1608static int parse_num(const char **cp_p)
1609{
1610        unsigned long num, scale;
1611        int ch, dot;
1612        const char *cp = *cp_p;
1613
1614        num = 0;
1615        scale = 1;
1616        dot = 0;
1617        for(;;) {
1618                ch = *cp;
1619                if ( !dot && ch == '.' ) {
1620                        scale = 1;
1621                        dot = 1;
1622                } else if ( ch == '%' ) {
1623                        scale = dot ? scale*100 : 100;
1624                        cp++;   /* % is always at the end */
1625                        break;
1626                } else if ( ch >= '0' && ch <= '9' ) {
1627                        if ( scale < 100000 ) {
1628                                scale *= 10;
1629                                num = (num*10) + (ch-'0');
1630                        }
1631                } else {
1632                        break;
1633                }
1634                cp++;
1635        }
1636        *cp_p = cp;
1637
1638        /* user says num divided by scale and we say internally that
1639         * is MAX_SCORE * num / scale.
1640         */
1641        return (num >= scale) ? MAX_SCORE : (MAX_SCORE * num / scale);
1642}
1643
1644int diff_scoreopt_parse(const char *opt)
1645{
1646        int opt1, opt2, cmd;
1647
1648        if (*opt++ != '-')
1649                return -1;
1650        cmd = *opt++;
1651        if (cmd != 'M' && cmd != 'C' && cmd != 'B')
1652                return -1; /* that is not a -M, -C nor -B option */
1653
1654        opt1 = parse_num(&opt);
1655        if (cmd != 'B')
1656                opt2 = 0;
1657        else {
1658                if (*opt == 0)
1659                        opt2 = 0;
1660                else if (*opt != '/')
1661                        return -1; /* we expect -B80/99 or -B80 */
1662                else {
1663                        opt++;
1664                        opt2 = parse_num(&opt);
1665                }
1666        }
1667        if (*opt != 0)
1668                return -1;
1669        return opt1 | (opt2 << 16);
1670}
1671
1672struct diff_queue_struct diff_queued_diff;
1673
1674void diff_q(struct diff_queue_struct *queue, struct diff_filepair *dp)
1675{
1676        if (queue->alloc <= queue->nr) {
1677                queue->alloc = alloc_nr(queue->alloc);
1678                queue->queue = xrealloc(queue->queue,
1679                                        sizeof(dp) * queue->alloc);
1680        }
1681        queue->queue[queue->nr++] = dp;
1682}
1683
1684struct diff_filepair *diff_queue(struct diff_queue_struct *queue,
1685                                 struct diff_filespec *one,
1686                                 struct diff_filespec *two)
1687{
1688        struct diff_filepair *dp = xmalloc(sizeof(*dp));
1689        dp->one = one;
1690        dp->two = two;
1691        dp->score = 0;
1692        dp->status = 0;
1693        dp->source_stays = 0;
1694        dp->broken_pair = 0;
1695        if (queue)
1696                diff_q(queue, dp);
1697        return dp;
1698}
1699
1700void diff_free_filepair(struct diff_filepair *p)
1701{
1702        diff_free_filespec_data(p->one);
1703        diff_free_filespec_data(p->two);
1704        free(p->one);
1705        free(p->two);
1706        free(p);
1707}
1708
1709/* This is different from find_unique_abbrev() in that
1710 * it stuffs the result with dots for alignment.
1711 */
1712const char *diff_unique_abbrev(const unsigned char *sha1, int len)
1713{
1714        int abblen;
1715        const char *abbrev;
1716        if (len == 40)
1717                return sha1_to_hex(sha1);
1718
1719        abbrev = find_unique_abbrev(sha1, len);
1720        if (!abbrev)
1721                return sha1_to_hex(sha1);
1722        abblen = strlen(abbrev);
1723        if (abblen < 37) {
1724                static char hex[41];
1725                if (len < abblen && abblen <= len + 2)
1726                        sprintf(hex, "%s%.*s", abbrev, len+3-abblen, "..");
1727                else
1728                        sprintf(hex, "%s...", abbrev);
1729                return hex;
1730        }
1731        return sha1_to_hex(sha1);
1732}
1733
1734static void diff_flush_raw(struct diff_filepair *p,
1735                           int line_termination,
1736                           int inter_name_termination,
1737                           struct diff_options *options,
1738                           int output_format)
1739{
1740        int two_paths;
1741        char status[10];
1742        int abbrev = options->abbrev;
1743        const char *path_one, *path_two;
1744
1745        path_one = p->one->path;
1746        path_two = p->two->path;
1747        if (line_termination) {
1748                path_one = quote_one(path_one);
1749                path_two = quote_one(path_two);
1750        }
1751
1752        if (p->score)
1753                sprintf(status, "%c%03d", p->status,
1754                        (int)(0.5 + p->score * 100.0/MAX_SCORE));
1755        else {
1756                status[0] = p->status;
1757                status[1] = 0;
1758        }
1759        switch (p->status) {
1760        case DIFF_STATUS_COPIED:
1761        case DIFF_STATUS_RENAMED:
1762                two_paths = 1;
1763                break;
1764        case DIFF_STATUS_ADDED:
1765        case DIFF_STATUS_DELETED:
1766                two_paths = 0;
1767                break;
1768        default:
1769                two_paths = 0;
1770                break;
1771        }
1772        if (output_format != DIFF_FORMAT_NAME_STATUS) {
1773                printf(":%06o %06o %s ",
1774                       p->one->mode, p->two->mode,
1775                       diff_unique_abbrev(p->one->sha1, abbrev));
1776                printf("%s ",
1777                       diff_unique_abbrev(p->two->sha1, abbrev));
1778        }
1779        printf("%s%c%s", status, inter_name_termination, path_one);
1780        if (two_paths)
1781                printf("%c%s", inter_name_termination, path_two);
1782        putchar(line_termination);
1783        if (path_one != p->one->path)
1784                free((void*)path_one);
1785        if (path_two != p->two->path)
1786                free((void*)path_two);
1787}
1788
1789static void diff_flush_name(struct diff_filepair *p, int line_termination)
1790{
1791        char *path = p->two->path;
1792
1793        if (line_termination)
1794                path = quote_one(p->two->path);
1795        printf("%s%c", path, line_termination);
1796        if (p->two->path != path)
1797                free(path);
1798}
1799
1800int diff_unmodified_pair(struct diff_filepair *p)
1801{
1802        /* This function is written stricter than necessary to support
1803         * the currently implemented transformers, but the idea is to
1804         * let transformers to produce diff_filepairs any way they want,
1805         * and filter and clean them up here before producing the output.
1806         */
1807        struct diff_filespec *one, *two;
1808
1809        if (DIFF_PAIR_UNMERGED(p))
1810                return 0; /* unmerged is interesting */
1811
1812        one = p->one;
1813        two = p->two;
1814
1815        /* deletion, addition, mode or type change
1816         * and rename are all interesting.
1817         */
1818        if (DIFF_FILE_VALID(one) != DIFF_FILE_VALID(two) ||
1819            DIFF_PAIR_MODE_CHANGED(p) ||
1820            strcmp(one->path, two->path))
1821                return 0;
1822
1823        /* both are valid and point at the same path.  that is, we are
1824         * dealing with a change.
1825         */
1826        if (one->sha1_valid && two->sha1_valid &&
1827            !memcmp(one->sha1, two->sha1, sizeof(one->sha1)))
1828                return 1; /* no change */
1829        if (!one->sha1_valid && !two->sha1_valid)
1830                return 1; /* both look at the same file on the filesystem. */
1831        return 0;
1832}
1833
1834static void diff_flush_patch(struct diff_filepair *p, struct diff_options *o)
1835{
1836        if (diff_unmodified_pair(p))
1837                return;
1838
1839        if ((DIFF_FILE_VALID(p->one) && S_ISDIR(p->one->mode)) ||
1840            (DIFF_FILE_VALID(p->two) && S_ISDIR(p->two->mode)))
1841                return; /* no tree diffs in patch format */
1842
1843        run_diff(p, o);
1844}
1845
1846static void diff_flush_stat(struct diff_filepair *p, struct diff_options *o,
1847                            struct diffstat_t *diffstat)
1848{
1849        if (diff_unmodified_pair(p))
1850                return;
1851
1852        if ((DIFF_FILE_VALID(p->one) && S_ISDIR(p->one->mode)) ||
1853            (DIFF_FILE_VALID(p->two) && S_ISDIR(p->two->mode)))
1854                return; /* no tree diffs in patch format */
1855
1856        run_diffstat(p, o, diffstat);
1857}
1858
1859static void diff_flush_checkdiff(struct diff_filepair *p,
1860                struct diff_options *o)
1861{
1862        if (diff_unmodified_pair(p))
1863                return;
1864
1865        if ((DIFF_FILE_VALID(p->one) && S_ISDIR(p->one->mode)) ||
1866            (DIFF_FILE_VALID(p->two) && S_ISDIR(p->two->mode)))
1867                return; /* no tree diffs in patch format */
1868
1869        run_checkdiff(p, o);
1870}
1871
1872int diff_queue_is_empty(void)
1873{
1874        struct diff_queue_struct *q = &diff_queued_diff;
1875        int i;
1876        for (i = 0; i < q->nr; i++)
1877                if (!diff_unmodified_pair(q->queue[i]))
1878                        return 0;
1879        return 1;
1880}
1881
1882#if DIFF_DEBUG
1883void diff_debug_filespec(struct diff_filespec *s, int x, const char *one)
1884{
1885        fprintf(stderr, "queue[%d] %s (%s) %s %06o %s\n",
1886                x, one ? one : "",
1887                s->path,
1888                DIFF_FILE_VALID(s) ? "valid" : "invalid",
1889                s->mode,
1890                s->sha1_valid ? sha1_to_hex(s->sha1) : "");
1891        fprintf(stderr, "queue[%d] %s size %lu flags %d\n",
1892                x, one ? one : "",
1893                s->size, s->xfrm_flags);
1894}
1895
1896void diff_debug_filepair(const struct diff_filepair *p, int i)
1897{
1898        diff_debug_filespec(p->one, i, "one");
1899        diff_debug_filespec(p->two, i, "two");
1900        fprintf(stderr, "score %d, status %c stays %d broken %d\n",
1901                p->score, p->status ? p->status : '?',
1902                p->source_stays, p->broken_pair);
1903}
1904
1905void diff_debug_queue(const char *msg, struct diff_queue_struct *q)
1906{
1907        int i;
1908        if (msg)
1909                fprintf(stderr, "%s\n", msg);
1910        fprintf(stderr, "q->nr = %d\n", q->nr);
1911        for (i = 0; i < q->nr; i++) {
1912                struct diff_filepair *p = q->queue[i];
1913                diff_debug_filepair(p, i);
1914        }
1915}
1916#endif
1917
1918static void diff_resolve_rename_copy(void)
1919{
1920        int i, j;
1921        struct diff_filepair *p, *pp;
1922        struct diff_queue_struct *q = &diff_queued_diff;
1923
1924        diff_debug_queue("resolve-rename-copy", q);
1925
1926        for (i = 0; i < q->nr; i++) {
1927                p = q->queue[i];
1928                p->status = 0; /* undecided */
1929                if (DIFF_PAIR_UNMERGED(p))
1930                        p->status = DIFF_STATUS_UNMERGED;
1931                else if (!DIFF_FILE_VALID(p->one))
1932                        p->status = DIFF_STATUS_ADDED;
1933                else if (!DIFF_FILE_VALID(p->two))
1934                        p->status = DIFF_STATUS_DELETED;
1935                else if (DIFF_PAIR_TYPE_CHANGED(p))
1936                        p->status = DIFF_STATUS_TYPE_CHANGED;
1937
1938                /* from this point on, we are dealing with a pair
1939                 * whose both sides are valid and of the same type, i.e.
1940                 * either in-place edit or rename/copy edit.
1941                 */
1942                else if (DIFF_PAIR_RENAME(p)) {
1943                        if (p->source_stays) {
1944                                p->status = DIFF_STATUS_COPIED;
1945                                continue;
1946                        }
1947                        /* See if there is some other filepair that
1948                         * copies from the same source as us.  If so
1949                         * we are a copy.  Otherwise we are either a
1950                         * copy if the path stays, or a rename if it
1951                         * does not, but we already handled "stays" case.
1952                         */
1953                        for (j = i + 1; j < q->nr; j++) {
1954                                pp = q->queue[j];
1955                                if (strcmp(pp->one->path, p->one->path))
1956                                        continue; /* not us */
1957                                if (!DIFF_PAIR_RENAME(pp))
1958                                        continue; /* not a rename/copy */
1959                                /* pp is a rename/copy from the same source */
1960                                p->status = DIFF_STATUS_COPIED;
1961                                break;
1962                        }
1963                        if (!p->status)
1964                                p->status = DIFF_STATUS_RENAMED;
1965                }
1966                else if (memcmp(p->one->sha1, p->two->sha1, 20) ||
1967                         p->one->mode != p->two->mode)
1968                        p->status = DIFF_STATUS_MODIFIED;
1969                else {
1970                        /* This is a "no-change" entry and should not
1971                         * happen anymore, but prepare for broken callers.
1972                         */
1973                        error("feeding unmodified %s to diffcore",
1974                              p->one->path);
1975                        p->status = DIFF_STATUS_UNKNOWN;
1976                }
1977        }
1978        diff_debug_queue("resolve-rename-copy done", q);
1979}
1980
1981static void flush_one_pair(struct diff_filepair *p,
1982                           int diff_output_format,
1983                           struct diff_options *options,
1984                           struct diffstat_t *diffstat)
1985{
1986        int inter_name_termination = '\t';
1987        int line_termination = options->line_termination;
1988        if (!line_termination)
1989                inter_name_termination = 0;
1990
1991        switch (p->status) {
1992        case DIFF_STATUS_UNKNOWN:
1993                break;
1994        case 0:
1995                die("internal error in diff-resolve-rename-copy");
1996                break;
1997        default:
1998                switch (diff_output_format) {
1999                case DIFF_FORMAT_DIFFSTAT:
2000                        diff_flush_stat(p, options, diffstat);
2001                        break;
2002                case DIFF_FORMAT_CHECKDIFF:
2003                        diff_flush_checkdiff(p, options);
2004                        break;
2005                case DIFF_FORMAT_PATCH:
2006                        diff_flush_patch(p, options);
2007                        break;
2008                case DIFF_FORMAT_RAW:
2009                case DIFF_FORMAT_NAME_STATUS:
2010                        diff_flush_raw(p, line_termination,
2011                                       inter_name_termination,
2012                                       options, diff_output_format);
2013                        break;
2014                case DIFF_FORMAT_NAME:
2015                        diff_flush_name(p, line_termination);
2016                        break;
2017                case DIFF_FORMAT_NO_OUTPUT:
2018                        break;
2019                }
2020        }
2021}
2022
2023static void show_file_mode_name(const char *newdelete, struct diff_filespec *fs)
2024{
2025        if (fs->mode)
2026                printf(" %s mode %06o %s\n", newdelete, fs->mode, fs->path);
2027        else
2028                printf(" %s %s\n", newdelete, fs->path);
2029}
2030
2031
2032static void show_mode_change(struct diff_filepair *p, int show_name)
2033{
2034        if (p->one->mode && p->two->mode && p->one->mode != p->two->mode) {
2035                if (show_name)
2036                        printf(" mode change %06o => %06o %s\n",
2037                               p->one->mode, p->two->mode, p->two->path);
2038                else
2039                        printf(" mode change %06o => %06o\n",
2040                               p->one->mode, p->two->mode);
2041        }
2042}
2043
2044static void show_rename_copy(const char *renamecopy, struct diff_filepair *p)
2045{
2046        const char *old, *new;
2047
2048        /* Find common prefix */
2049        old = p->one->path;
2050        new = p->two->path;
2051        while (1) {
2052                const char *slash_old, *slash_new;
2053                slash_old = strchr(old, '/');
2054                slash_new = strchr(new, '/');
2055                if (!slash_old ||
2056                    !slash_new ||
2057                    slash_old - old != slash_new - new ||
2058                    memcmp(old, new, slash_new - new))
2059                        break;
2060                old = slash_old + 1;
2061                new = slash_new + 1;
2062        }
2063        /* p->one->path thru old is the common prefix, and old and new
2064         * through the end of names are renames
2065         */
2066        if (old != p->one->path)
2067                printf(" %s %.*s{%s => %s} (%d%%)\n", renamecopy,
2068                       (int)(old - p->one->path), p->one->path,
2069                       old, new, (int)(0.5 + p->score * 100.0/MAX_SCORE));
2070        else
2071                printf(" %s %s => %s (%d%%)\n", renamecopy,
2072                       p->one->path, p->two->path,
2073                       (int)(0.5 + p->score * 100.0/MAX_SCORE));
2074        show_mode_change(p, 0);
2075}
2076
2077static void diff_summary(struct diff_filepair *p)
2078{
2079        switch(p->status) {
2080        case DIFF_STATUS_DELETED:
2081                show_file_mode_name("delete", p->one);
2082                break;
2083        case DIFF_STATUS_ADDED:
2084                show_file_mode_name("create", p->two);
2085                break;
2086        case DIFF_STATUS_COPIED:
2087                show_rename_copy("copy", p);
2088                break;
2089        case DIFF_STATUS_RENAMED:
2090                show_rename_copy("rename", p);
2091                break;
2092        default:
2093                if (p->score) {
2094                        printf(" rewrite %s (%d%%)\n", p->two->path,
2095                                (int)(0.5 + p->score * 100.0/MAX_SCORE));
2096                        show_mode_change(p, 0);
2097                } else  show_mode_change(p, 1);
2098                break;
2099        }
2100}
2101
2102void diff_flush(struct diff_options *options)
2103{
2104        struct diff_queue_struct *q = &diff_queued_diff;
2105        int i;
2106        int diff_output_format = options->output_format;
2107        struct diffstat_t *diffstat = NULL;
2108
2109        if (diff_output_format == DIFF_FORMAT_DIFFSTAT || options->with_stat) {
2110                diffstat = xcalloc(sizeof (struct diffstat_t), 1);
2111                diffstat->xm.consume = diffstat_consume;
2112        }
2113
2114        if (options->with_raw) {
2115                for (i = 0; i < q->nr; i++) {
2116                        struct diff_filepair *p = q->queue[i];
2117                        flush_one_pair(p, DIFF_FORMAT_RAW, options, NULL);
2118                }
2119                putchar(options->line_termination);
2120        }
2121        if (options->with_stat) {
2122                for (i = 0; i < q->nr; i++) {
2123                        struct diff_filepair *p = q->queue[i];
2124                        flush_one_pair(p, DIFF_FORMAT_DIFFSTAT, options,
2125                                       diffstat);
2126                }
2127                show_stats(diffstat);
2128                free(diffstat);
2129                diffstat = NULL;
2130                if (options->summary)
2131                        for (i = 0; i < q->nr; i++)
2132                                diff_summary(q->queue[i]);
2133                if (options->stat_sep)
2134                        fputs(options->stat_sep, stdout);
2135                else
2136                        putchar(options->line_termination);
2137        }
2138        for (i = 0; i < q->nr; i++) {
2139                struct diff_filepair *p = q->queue[i];
2140                flush_one_pair(p, diff_output_format, options, diffstat);
2141        }
2142
2143        if (diffstat) {
2144                show_stats(diffstat);
2145                free(diffstat);
2146        }
2147
2148        for (i = 0; i < q->nr; i++) {
2149                if (diffstat && options->summary)
2150                        diff_summary(q->queue[i]);
2151                diff_free_filepair(q->queue[i]);
2152        }
2153
2154        free(q->queue);
2155        q->queue = NULL;
2156        q->nr = q->alloc = 0;
2157}
2158
2159static void diffcore_apply_filter(const char *filter)
2160{
2161        int i;
2162        struct diff_queue_struct *q = &diff_queued_diff;
2163        struct diff_queue_struct outq;
2164        outq.queue = NULL;
2165        outq.nr = outq.alloc = 0;
2166
2167        if (!filter)
2168                return;
2169
2170        if (strchr(filter, DIFF_STATUS_FILTER_AON)) {
2171                int found;
2172                for (i = found = 0; !found && i < q->nr; i++) {
2173                        struct diff_filepair *p = q->queue[i];
2174                        if (((p->status == DIFF_STATUS_MODIFIED) &&
2175                             ((p->score &&
2176                               strchr(filter, DIFF_STATUS_FILTER_BROKEN)) ||
2177                              (!p->score &&
2178                               strchr(filter, DIFF_STATUS_MODIFIED)))) ||
2179                            ((p->status != DIFF_STATUS_MODIFIED) &&
2180                             strchr(filter, p->status)))
2181                                found++;
2182                }
2183                if (found)
2184                        return;
2185
2186                /* otherwise we will clear the whole queue
2187                 * by copying the empty outq at the end of this
2188                 * function, but first clear the current entries
2189                 * in the queue.
2190                 */
2191                for (i = 0; i < q->nr; i++)
2192                        diff_free_filepair(q->queue[i]);
2193        }
2194        else {
2195                /* Only the matching ones */
2196                for (i = 0; i < q->nr; i++) {
2197                        struct diff_filepair *p = q->queue[i];
2198
2199                        if (((p->status == DIFF_STATUS_MODIFIED) &&
2200                             ((p->score &&
2201                               strchr(filter, DIFF_STATUS_FILTER_BROKEN)) ||
2202                              (!p->score &&
2203                               strchr(filter, DIFF_STATUS_MODIFIED)))) ||
2204                            ((p->status != DIFF_STATUS_MODIFIED) &&
2205                             strchr(filter, p->status)))
2206                                diff_q(&outq, p);
2207                        else
2208                                diff_free_filepair(p);
2209                }
2210        }
2211        free(q->queue);
2212        *q = outq;
2213}
2214
2215void diffcore_std(struct diff_options *options)
2216{
2217        if (options->break_opt != -1)
2218                diffcore_break(options->break_opt);
2219        if (options->detect_rename)
2220                diffcore_rename(options);
2221        if (options->break_opt != -1)
2222                diffcore_merge_broken();
2223        if (options->pickaxe)
2224                diffcore_pickaxe(options->pickaxe, options->pickaxe_opts);
2225        if (options->orderfile)
2226                diffcore_order(options->orderfile);
2227        diff_resolve_rename_copy();
2228        diffcore_apply_filter(options->filter);
2229}
2230
2231
2232void diffcore_std_no_resolve(struct diff_options *options)
2233{
2234        if (options->pickaxe)
2235                diffcore_pickaxe(options->pickaxe, options->pickaxe_opts);
2236        if (options->orderfile)
2237                diffcore_order(options->orderfile);
2238        diffcore_apply_filter(options->filter);
2239}
2240
2241void diff_addremove(struct diff_options *options,
2242                    int addremove, unsigned mode,
2243                    const unsigned char *sha1,
2244                    const char *base, const char *path)
2245{
2246        char concatpath[PATH_MAX];
2247        struct diff_filespec *one, *two;
2248
2249        /* This may look odd, but it is a preparation for
2250         * feeding "there are unchanged files which should
2251         * not produce diffs, but when you are doing copy
2252         * detection you would need them, so here they are"
2253         * entries to the diff-core.  They will be prefixed
2254         * with something like '=' or '*' (I haven't decided
2255         * which but should not make any difference).
2256         * Feeding the same new and old to diff_change() 
2257         * also has the same effect.
2258         * Before the final output happens, they are pruned after
2259         * merged into rename/copy pairs as appropriate.
2260         */
2261        if (options->reverse_diff)
2262                addremove = (addremove == '+' ? '-' :
2263                             addremove == '-' ? '+' : addremove);
2264
2265        if (!path) path = "";
2266        sprintf(concatpath, "%s%s", base, path);
2267        one = alloc_filespec(concatpath);
2268        two = alloc_filespec(concatpath);
2269
2270        if (addremove != '+')
2271                fill_filespec(one, sha1, mode);
2272        if (addremove != '-')
2273                fill_filespec(two, sha1, mode);
2274
2275        diff_queue(&diff_queued_diff, one, two);
2276}
2277
2278void diff_change(struct diff_options *options,
2279                 unsigned old_mode, unsigned new_mode,
2280                 const unsigned char *old_sha1,
2281                 const unsigned char *new_sha1,
2282                 const char *base, const char *path) 
2283{
2284        char concatpath[PATH_MAX];
2285        struct diff_filespec *one, *two;
2286
2287        if (options->reverse_diff) {
2288                unsigned tmp;
2289                const unsigned char *tmp_c;
2290                tmp = old_mode; old_mode = new_mode; new_mode = tmp;
2291                tmp_c = old_sha1; old_sha1 = new_sha1; new_sha1 = tmp_c;
2292        }
2293        if (!path) path = "";
2294        sprintf(concatpath, "%s%s", base, path);
2295        one = alloc_filespec(concatpath);
2296        two = alloc_filespec(concatpath);
2297        fill_filespec(one, old_sha1, old_mode);
2298        fill_filespec(two, new_sha1, new_mode);
2299
2300        diff_queue(&diff_queued_diff, one, two);
2301}
2302
2303void diff_unmerge(struct diff_options *options,
2304                  const char *path)
2305{
2306        struct diff_filespec *one, *two;
2307        one = alloc_filespec(path);
2308        two = alloc_filespec(path);
2309        diff_queue(&diff_queued_diff, one, two);
2310}