diff.c

   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 "xdiff/xdiff.h"
  12
  13 static int use_size_cache;
  14
  15 int diff_rename_limit_default = -1;
  16
  17 int git_diff_config(const char *var, const char *value)
  18 {
  19         if (!strcmp(var, "diff.renamelimit")) {
  20                 diff_rename_limit_default = git_config_int(var, value);
  21                 return 0;
  22         }
  23
  24         return git_default_config(var, value);
  25 }
  26
  27 static char *quote_one(const char *str)
  28 {
  29         int needlen;
  30         char *xp;
  31
  32         if (!str)
  33                 return NULL;
  34         needlen = quote_c_style(str, NULL, NULL, 0);
  35         if (!needlen)
  36                 return strdup(str);
  37         xp = xmalloc(needlen + 1);
  38         quote_c_style(str, xp, NULL, 0);
  39         return xp;
  40 }
  41
  42 static char *quote_two(const char *one, const char *two)
  43 {
  44         int need_one = quote_c_style(one, NULL, NULL, 1);
  45         int need_two = quote_c_style(two, NULL, NULL, 1);
  46         char *xp;
  47
  48         if (need_one + need_two) {
  49                 if (!need_one) need_one = strlen(one);
  50                 if (!need_two) need_one = strlen(two);
  51
  52                 xp = xmalloc(need_one + need_two + 3);
  53                 xp[0] = '"';
  54                 quote_c_style(one, xp + 1, NULL, 1);
  55                 quote_c_style(two, xp + need_one + 1, NULL, 1);
  56                 strcpy(xp + need_one + need_two + 1, "\"");
  57                 return xp;
  58         }
  59         need_one = strlen(one);
  60         need_two = strlen(two);
  61         xp = xmalloc(need_one + need_two + 1);
  62         strcpy(xp, one);
  63         strcpy(xp + need_one, two);
  64         return xp;
  65 }
  66
  67 static const char *external_diff(void)
  68 {
  69         static const char *external_diff_cmd = NULL;
  70         static int done_preparing = 0;
  71
  72         if (done_preparing)
  73                 return external_diff_cmd;
  74         external_diff_cmd = getenv("GIT_EXTERNAL_DIFF");
  75         done_preparing = 1;
  76         return external_diff_cmd;
  77 }
  78
  79 #define TEMPFILE_PATH_LEN               50
  80
  81 static struct diff_tempfile {
  82         const char *name; /* filename external diff should read from */
  83         char hex[41];
  84         char mode[10];
  85         char tmp_path[TEMPFILE_PATH_LEN];
  86 } diff_temp[2];
  87
  88 static int count_lines(const char *data, int size)
  89 {
  90         int count, ch, completely_empty = 1, nl_just_seen = 0;
  91         count = 0;
  92         while (0 < size--) {
  93                 ch = *data++;
  94                 if (ch == '\n') {
  95                         count++;
  96                         nl_just_seen = 1;
  97                         completely_empty = 0;
  98                 }
  99                 else {
 100                         nl_just_seen = 0;
 101                         completely_empty = 0;
 102                 }
 103         }
 104         if (completely_empty)
 105                 return 0;
 106         if (!nl_just_seen)
 107                 count++; /* no trailing newline */
 108         return count;
 109 }
 110
 111 static void print_line_count(int count)
 112 {
 113         switch (count) {
 114         case 0:
 115                 printf("0,0");
 116                 break;
 117         case 1:
 118                 printf("1");
 119                 break;
 120         default:
 121                 printf("1,%d", count);
 122                 break;
 123         }
 124 }
 125
 126 static void copy_file(int prefix, const char *data, int size)
 127 {
 128         int ch, nl_just_seen = 1;
 129         while (0 < size--) {
 130                 ch = *data++;
 131                 if (nl_just_seen)
 132                         putchar(prefix);
 133                 putchar(ch);
 134                 if (ch == '\n')
 135                         nl_just_seen = 1;
 136                 else
 137                         nl_just_seen = 0;
 138         }
 139         if (!nl_just_seen)
 140                 printf("\n\\ No newline at end of file\n");
 141 }
 142
 143 static void emit_rewrite_diff(const char *name_a,
 144                               const char *name_b,
 145                               struct diff_filespec *one,
 146                               struct diff_filespec *two)
 147 {
 148         /* Use temp[i].name as input, name_a and name_b as labels */
 149         int lc_a, lc_b;
 150         lc_a = count_lines(one->data, one->size);
 151         lc_b = count_lines(two->data, two->size);
 152         printf("--- %s\n+++ %s\n@@ -", name_a, name_b);
 153         print_line_count(lc_a);
 154         printf(" +");
 155         print_line_count(lc_b);
 156         printf(" @@\n");
 157         if (lc_a)
 158                 copy_file('-', one->data, one->size);
 159         if (lc_b)
 160                 copy_file('+', two->data, two->size);
 161 }
 162
 163 static int fill_mmfile(mmfile_t *mf, struct diff_filespec *one)
 164 {
 165         if (!DIFF_FILE_VALID(one)) {
 166                 mf->ptr = ""; /* does not matter */
 167                 mf->size = 0;
 168                 return 0;
 169         }
 170         else if (diff_populate_filespec(one, 0))
 171                 return -1;
 172         mf->ptr = one->data;
 173         mf->size = one->size;
 174         return 0;
 175 }
 176
 177 struct emit_callback {
 178         const char **label_path;
 179 };
 180
 181 static int fn_out(void *priv, mmbuffer_t *mb, int nbuf)
 182 {
 183         int i;
 184         struct emit_callback *ecbdata = priv;
 185
 186         if (ecbdata->label_path[0]) {
 187                 printf("--- %s\n", ecbdata->label_path[0]);
 188                 printf("+++ %s\n", ecbdata->label_path[1]);
 189                 ecbdata->label_path[0] = ecbdata->label_path[1] = NULL;
 190         }
 191         for (i = 0; i < nbuf; i++)
 192                 if (!fwrite(mb[i].ptr, mb[i].size, 1, stdout))
 193                         return -1;
 194         return 0;
 195 }
 196
 197 #define FIRST_FEW_BYTES 8000
 198 static int mmfile_is_binary(mmfile_t *mf)
 199 {
 200         long sz = mf->size;
 201         if (FIRST_FEW_BYTES < sz)
 202                 sz = FIRST_FEW_BYTES;
 203         if (memchr(mf->ptr, 0, sz))
 204                 return 1;
 205         return 0;
 206 }
 207
 208 static void builtin_diff(const char *name_a,
 209                          const char *name_b,
 210                          struct diff_filespec *one,
 211                          struct diff_filespec *two,
 212                          const char *xfrm_msg,
 213                          int complete_rewrite)
 214 {
 215         mmfile_t mf1, mf2;
 216         const char *lbl[2];
 217         char *a_one, *b_two;
 218
 219         a_one = quote_two("a/", name_a);
 220         b_two = quote_two("b/", name_b);
 221         lbl[0] = DIFF_FILE_VALID(one) ? a_one : "/dev/null";
 222         lbl[1] = DIFF_FILE_VALID(two) ? b_two : "/dev/null";
 223         printf("diff --git %s %s\n", a_one, b_two);
 224         if (lbl[0][0] == '/') {
 225                 /* /dev/null */
 226                 printf("new file mode %06o\n", two->mode);
 227                 if (xfrm_msg && xfrm_msg[0])
 228                         puts(xfrm_msg);
 229         }
 230         else if (lbl[1][0] == '/') {
 231                 printf("deleted file mode %06o\n", one->mode);
 232                 if (xfrm_msg && xfrm_msg[0])
 233                         puts(xfrm_msg);
 234         }
 235         else {
 236                 if (one->mode != two->mode) {
 237                         printf("old mode %06o\n", one->mode);
 238                         printf("new mode %06o\n", two->mode);
 239                 }
 240                 if (xfrm_msg && xfrm_msg[0])
 241                         puts(xfrm_msg);
 242                 /*
 243                  * we do not run diff between different kind
 244                  * of objects.
 245                  */
 246                 if ((one->mode ^ two->mode) & S_IFMT)
 247                         goto free_ab_and_return;
 248                 if (complete_rewrite) {
 249                         emit_rewrite_diff(name_a, name_b, one, two);
 250                         goto free_ab_and_return;
 251                 }
 252         }
 253
 254         if (fill_mmfile(&mf1, one) < 0 || fill_mmfile(&mf2, two) < 0)
 255                 die("unable to read files to diff");
 256
 257         if (mmfile_is_binary(&mf1) || mmfile_is_binary(&mf2))
 258                 printf("Binary files %s and %s differ\n", lbl[0], lbl[1]);
 259         else {
 260                 /* Crazy xdl interfaces.. */
 261                 const char *diffopts = getenv("GIT_DIFF_OPTS");
 262                 xpparam_t xpp;
 263                 xdemitconf_t xecfg;
 264                 xdemitcb_t ecb;
 265                 struct emit_callback ecbdata;
 266
 267                 ecbdata.label_path = lbl;
 268                 xpp.flags = XDF_NEED_MINIMAL;
 269                 xecfg.ctxlen = 3;
 270                 if (!diffopts)
 271                         ;
 272                 else if (!strncmp(diffopts, "--unified=", 10))
 273                         xecfg.ctxlen = strtoul(diffopts + 10, NULL, 10);
 274                 else if (!strncmp(diffopts, "-u", 2))
 275                         xecfg.ctxlen = strtoul(diffopts + 2, NULL, 10);
 276                 ecb.outf = fn_out;
 277                 ecb.priv = &ecbdata;
 278                 xdl_diff(&mf1, &mf2, &xpp, &xecfg, &ecb);
 279         }
 280
 281  free_ab_and_return:
 282         free(a_one);
 283         free(b_two);
 284         return;
 285 }
 286
 287 struct diff_filespec *alloc_filespec(const char *path)
 288 {
 289         int namelen = strlen(path);
 290         struct diff_filespec *spec = xmalloc(sizeof(*spec) + namelen + 1);
 291
 292         memset(spec, 0, sizeof(*spec));
 293         spec->path = (char *)(spec + 1);
 294         memcpy(spec->path, path, namelen+1);
 295         return spec;
 296 }
 297
 298 void fill_filespec(struct diff_filespec *spec, const unsigned char *sha1,
 299                    unsigned short mode)
 300 {
 301         if (mode) {
 302                 spec->mode = DIFF_FILE_CANON_MODE(mode);
 303                 memcpy(spec->sha1, sha1, 20);
 304                 spec->sha1_valid = !!memcmp(sha1, null_sha1, 20);
 305         }
 306 }
 307
 308 /*
 309  * Given a name and sha1 pair, if the dircache tells us the file in
 310  * the work tree has that object contents, return true, so that
 311  * prepare_temp_file() does not have to inflate and extract.
 312  */
 313 static int work_tree_matches(const char *name, const unsigned char *sha1)
 314 {
 315         struct cache_entry *ce;
 316         struct stat st;
 317         int pos, len;
 318
 319         /* We do not read the cache ourselves here, because the
 320          * benchmark with my previous version that always reads cache
 321          * shows that it makes things worse for diff-tree comparing
 322          * two linux-2.6 kernel trees in an already checked out work
 323          * tree.  This is because most diff-tree comparisons deal with
 324          * only a small number of files, while reading the cache is
 325          * expensive for a large project, and its cost outweighs the
 326          * savings we get by not inflating the object to a temporary
 327          * file.  Practically, this code only helps when we are used
 328          * by diff-cache --cached, which does read the cache before
 329          * calling us.
 330          */
 331         if (!active_cache)
 332                 return 0;
 333
 334         len = strlen(name);
 335         pos = cache_name_pos(name, len);
 336         if (pos < 0)
 337                 return 0;
 338         ce = active_cache[pos];
 339         if ((lstat(name, &st) < 0) ||
 340             !S_ISREG(st.st_mode) || /* careful! */
 341             ce_match_stat(ce, &st, 0) ||
 342             memcmp(sha1, ce->sha1, 20))
 343                 return 0;
 344         /* we return 1 only when we can stat, it is a regular file,
 345          * stat information matches, and sha1 recorded in the cache
 346          * matches.  I.e. we know the file in the work tree really is
 347          * the same as the <name, sha1> pair.
 348          */
 349         return 1;
 350 }
 351
 352 static struct sha1_size_cache {
 353         unsigned char sha1[20];
 354         unsigned long size;
 355 } **sha1_size_cache;
 356 static int sha1_size_cache_nr, sha1_size_cache_alloc;
 357
 358 static struct sha1_size_cache *locate_size_cache(unsigned char *sha1,
 359                                                  int find_only,
 360                                                  unsigned long size)
 361 {
 362         int first, last;
 363         struct sha1_size_cache *e;
 364
 365         first = 0;
 366         last = sha1_size_cache_nr;
 367         while (last > first) {
 368                 int cmp, next = (last + first) >> 1;
 369                 e = sha1_size_cache[next];
 370                 cmp = memcmp(e->sha1, sha1, 20);
 371                 if (!cmp)
 372                         return e;
 373                 if (cmp < 0) {
 374                         last = next;
 375                         continue;
 376                 }
 377                 first = next+1;
 378         }
 379         /* not found */
 380         if (find_only)
 381                 return NULL;
 382         /* insert to make it at "first" */
 383         if (sha1_size_cache_alloc <= sha1_size_cache_nr) {
 384                 sha1_size_cache_alloc = alloc_nr(sha1_size_cache_alloc);
 385                 sha1_size_cache = xrealloc(sha1_size_cache,
 386                                            sha1_size_cache_alloc *
 387                                            sizeof(*sha1_size_cache));
 388         }
 389         sha1_size_cache_nr++;
 390         if (first < sha1_size_cache_nr)
 391                 memmove(sha1_size_cache + first + 1, sha1_size_cache + first,
 392                         (sha1_size_cache_nr - first - 1) *
 393                         sizeof(*sha1_size_cache));
 394         e = xmalloc(sizeof(struct sha1_size_cache));
 395         sha1_size_cache[first] = e;
 396         memcpy(e->sha1, sha1, 20);
 397         e->size = size;
 398         return e;
 399 }
 400
 401 /*
 402  * While doing rename detection and pickaxe operation, we may need to
 403  * grab the data for the blob (or file) for our own in-core comparison.
 404  * diff_filespec has data and size fields for this purpose.
 405  */
 406 int diff_populate_filespec(struct diff_filespec *s, int size_only)
 407 {
 408         int err = 0;
 409         if (!DIFF_FILE_VALID(s))
 410                 die("internal error: asking to populate invalid file.");
 411         if (S_ISDIR(s->mode))
 412                 return -1;
 413
 414         if (!use_size_cache)
 415                 size_only = 0;
 416
 417         if (s->data)
 418                 return err;
 419         if (!s->sha1_valid ||
 420             work_tree_matches(s->path, s->sha1)) {
 421                 struct stat st;
 422                 int fd;
 423                 if (lstat(s->path, &st) < 0) {
 424                         if (errno == ENOENT) {
 425                         err_empty:
 426                                 err = -1;
 427                         empty:
 428                                 s->data = "";
 429                                 s->size = 0;
 430                                 return err;
 431                         }
 432                 }
 433                 s->size = st.st_size;
 434                 if (!s->size)
 435                         goto empty;
 436                 if (size_only)
 437                         return 0;
 438                 if (S_ISLNK(st.st_mode)) {
 439                         int ret;
 440                         s->data = xmalloc(s->size);
 441                         s->should_free = 1;
 442                         ret = readlink(s->path, s->data, s->size);
 443                         if (ret < 0) {
 444                                 free(s->data);
 445                                 goto err_empty;
 446                         }
 447                         return 0;
 448                 }
 449                 fd = open(s->path, O_RDONLY);
 450                 if (fd < 0)
 451                         goto err_empty;
 452                 s->data = mmap(NULL, s->size, PROT_READ, MAP_PRIVATE, fd, 0);
 453                 close(fd);
 454                 if (s->data == MAP_FAILED)
 455                         goto err_empty;
 456                 s->should_munmap = 1;
 457         }
 458         else {
 459                 char type[20];
 460                 struct sha1_size_cache *e;
 461
 462                 if (size_only) {
 463                         e = locate_size_cache(s->sha1, 1, 0);
 464                         if (e) {
 465                                 s->size = e->size;
 466                                 return 0;
 467                         }
 468                         if (!sha1_object_info(s->sha1, type, &s->size))
 469                                 locate_size_cache(s->sha1, 0, s->size);
 470                 }
 471                 else {
 472                         s->data = read_sha1_file(s->sha1, type, &s->size);
 473                         s->should_free = 1;
 474                 }
 475         }
 476         return 0;
 477 }
 478
 479 void diff_free_filespec_data(struct diff_filespec *s)
 480 {
 481         if (s->should_free)
 482                 free(s->data);
 483         else if (s->should_munmap)
 484                 munmap(s->data, s->size);
 485         s->should_free = s->should_munmap = 0;
 486         s->data = NULL;
 487         free(s->cnt_data);
 488         s->cnt_data = NULL;
 489 }
 490
 491 static void prep_temp_blob(struct diff_tempfile *temp,
 492                            void *blob,
 493                            unsigned long size,
 494                            const unsigned char *sha1,
 495                            int mode)
 496 {
 497         int fd;
 498
 499         fd = git_mkstemp(temp->tmp_path, TEMPFILE_PATH_LEN, ".diff_XXXXXX");
 500         if (fd < 0)
 501                 die("unable to create temp-file");
 502         if (write(fd, blob, size) != size)
 503                 die("unable to write temp-file");
 504         close(fd);
 505         temp->name = temp->tmp_path;
 506         strcpy(temp->hex, sha1_to_hex(sha1));
 507         temp->hex[40] = 0;
 508         sprintf(temp->mode, "%06o", mode);
 509 }
 510
 511 static void prepare_temp_file(const char *name,
 512                               struct diff_tempfile *temp,
 513                               struct diff_filespec *one)
 514 {
 515         if (!DIFF_FILE_VALID(one)) {
 516         not_a_valid_file:
 517                 /* A '-' entry produces this for file-2, and
 518                  * a '+' entry produces this for file-1.
 519                  */
 520                 temp->name = "/dev/null";
 521                 strcpy(temp->hex, ".");
 522                 strcpy(temp->mode, ".");
 523                 return;
 524         }
 525
 526         if (!one->sha1_valid ||
 527             work_tree_matches(name, one->sha1)) {
 528                 struct stat st;
 529                 if (lstat(name, &st) < 0) {
 530                         if (errno == ENOENT)
 531                                 goto not_a_valid_file;
 532                         die("stat(%s): %s", name, strerror(errno));
 533                 }
 534                 if (S_ISLNK(st.st_mode)) {
 535                         int ret;
 536                         char buf[PATH_MAX + 1]; /* ought to be SYMLINK_MAX */
 537                         if (sizeof(buf) <= st.st_size)
 538                                 die("symlink too long: %s", name);
 539                         ret = readlink(name, buf, st.st_size);
 540                         if (ret < 0)
 541                                 die("readlink(%s)", name);
 542                         prep_temp_blob(temp, buf, st.st_size,
 543                                        (one->sha1_valid ?
 544                                         one->sha1 : null_sha1),
 545                                        (one->sha1_valid ?
 546                                         one->mode : S_IFLNK));
 547                 }
 548                 else {
 549                         /* we can borrow from the file in the work tree */
 550                         temp->name = name;
 551                         if (!one->sha1_valid)
 552                                 strcpy(temp->hex, sha1_to_hex(null_sha1));
 553                         else
 554                                 strcpy(temp->hex, sha1_to_hex(one->sha1));
 555                         /* Even though we may sometimes borrow the
 556                          * contents from the work tree, we always want
 557                          * one->mode.  mode is trustworthy even when
 558                          * !(one->sha1_valid), as long as
 559                          * DIFF_FILE_VALID(one).
 560                          */
 561                         sprintf(temp->mode, "%06o", one->mode);
 562                 }
 563                 return;
 564         }
 565         else {
 566                 if (diff_populate_filespec(one, 0))
 567                         die("cannot read data blob for %s", one->path);
 568                 prep_temp_blob(temp, one->data, one->size,
 569                                one->sha1, one->mode);
 570         }
 571 }
 572
 573 static void remove_tempfile(void)
 574 {
 575         int i;
 576
 577         for (i = 0; i < 2; i++)
 578                 if (diff_temp[i].name == diff_temp[i].tmp_path) {
 579                         unlink(diff_temp[i].name);
 580                         diff_temp[i].name = NULL;
 581                 }
 582 }
 583
 584 static void remove_tempfile_on_signal(int signo)
 585 {
 586         remove_tempfile();
 587         signal(SIGINT, SIG_DFL);
 588         raise(signo);
 589 }
 590
 591 static int spawn_prog(const char *pgm, const char **arg)
 592 {
 593         pid_t pid;
 594         int status;
 595
 596         fflush(NULL);
 597         pid = fork();
 598         if (pid < 0)
 599                 die("unable to fork");
 600         if (!pid) {
 601                 execvp(pgm, (char *const*) arg);
 602                 exit(255);
 603         }
 604
 605         while (waitpid(pid, &status, 0) < 0) {
 606                 if (errno == EINTR)
 607                         continue;
 608                 return -1;
 609         }
 610
 611         /* Earlier we did not check the exit status because
 612          * diff exits non-zero if files are different, and
 613          * we are not interested in knowing that.  It was a
 614          * mistake which made it harder to quit a diff-*
 615          * session that uses the git-apply-patch-script as
 616          * the GIT_EXTERNAL_DIFF.  A custom GIT_EXTERNAL_DIFF
 617          * should also exit non-zero only when it wants to
 618          * abort the entire diff-* session.
 619          */
 620         if (WIFEXITED(status) && !WEXITSTATUS(status))
 621                 return 0;
 622         return -1;
 623 }
 624
 625 /* An external diff command takes:
 626  *
 627  * diff-cmd name infile1 infile1-sha1 infile1-mode \
 628  *               infile2 infile2-sha1 infile2-mode [ rename-to ]
 629  *
 630  */
 631 static void run_external_diff(const char *pgm,
 632                               const char *name,
 633                               const char *other,
 634                               struct diff_filespec *one,
 635                               struct diff_filespec *two,
 636                               const char *xfrm_msg,
 637                               int complete_rewrite)
 638 {
 639         const char *spawn_arg[10];
 640         struct diff_tempfile *temp = diff_temp;
 641         int retval;
 642         static int atexit_asked = 0;
 643         const char *othername;
 644         const char **arg = &spawn_arg[0];
 645
 646         othername = (other? other : name);
 647         if (one && two) {
 648                 prepare_temp_file(name, &temp[0], one);
 649                 prepare_temp_file(othername, &temp[1], two);
 650                 if (! atexit_asked &&
 651                     (temp[0].name == temp[0].tmp_path ||
 652                      temp[1].name == temp[1].tmp_path)) {
 653                         atexit_asked = 1;
 654                         atexit(remove_tempfile);
 655                 }
 656                 signal(SIGINT, remove_tempfile_on_signal);
 657         }
 658
 659         if (one && two) {
 660                 *arg++ = pgm;
 661                 *arg++ = name;
 662                 *arg++ = temp[0].name;
 663                 *arg++ = temp[0].hex;
 664                 *arg++ = temp[0].mode;
 665                 *arg++ = temp[1].name;
 666                 *arg++ = temp[1].hex;
 667                 *arg++ = temp[1].mode;
 668                 if (other) {
 669                         *arg++ = other;
 670                         *arg++ = xfrm_msg;
 671                 }
 672         } else {
 673                 *arg++ = pgm;
 674                 *arg++ = name;
 675         }
 676         *arg = NULL;
 677         retval = spawn_prog(pgm, spawn_arg);
 678         remove_tempfile();
 679         if (retval) {
 680                 fprintf(stderr, "external diff died, stopping at %s.\n", name);
 681                 exit(1);
 682         }
 683 }
 684
 685 static void run_diff_cmd(const char *pgm,
 686                          const char *name,
 687                          const char *other,
 688                          struct diff_filespec *one,
 689                          struct diff_filespec *two,
 690                          const char *xfrm_msg,
 691                          int complete_rewrite)
 692 {
 693         if (pgm) {
 694                 run_external_diff(pgm, name, other, one, two, xfrm_msg,
 695                                   complete_rewrite);
 696                 return;
 697         }
 698         if (one && two)
 699                 builtin_diff(name, other ? other : name,
 700                              one, two, xfrm_msg, complete_rewrite);
 701         else
 702                 printf("* Unmerged path %s\n", name);
 703 }
 704
 705 static void diff_fill_sha1_info(struct diff_filespec *one)
 706 {
 707         if (DIFF_FILE_VALID(one)) {
 708                 if (!one->sha1_valid) {
 709                         struct stat st;
 710                         if (lstat(one->path, &st) < 0)
 711                                 die("stat %s", one->path);
 712                         if (index_path(one->sha1, one->path, &st, 0))
 713                                 die("cannot hash %s\n", one->path);
 714                 }
 715         }
 716         else
 717                 memset(one->sha1, 0, 20);
 718 }
 719
 720 static void run_diff(struct diff_filepair *p, struct diff_options *o)
 721 {
 722         const char *pgm = external_diff();
 723         char msg[PATH_MAX*2+300], *xfrm_msg;
 724         struct diff_filespec *one;
 725         struct diff_filespec *two;
 726         const char *name;
 727         const char *other;
 728         char *name_munged, *other_munged;
 729         int complete_rewrite = 0;
 730         int len;
 731
 732         if (DIFF_PAIR_UNMERGED(p)) {
 733                 /* unmerged */
 734                 run_diff_cmd(pgm, p->one->path, NULL, NULL, NULL, NULL, 0);
 735                 return;
 736         }
 737
 738         name = p->one->path;
 739         other = (strcmp(name, p->two->path) ? p->two->path : NULL);
 740         name_munged = quote_one(name);
 741         other_munged = quote_one(other);
 742         one = p->one; two = p->two;
 743
 744         diff_fill_sha1_info(one);
 745         diff_fill_sha1_info(two);
 746
 747         len = 0;
 748         switch (p->status) {
 749         case DIFF_STATUS_COPIED:
 750                 len += snprintf(msg + len, sizeof(msg) - len,
 751                                 "similarity index %d%%\n"
 752                                 "copy from %s\n"
 753                                 "copy to %s\n",
 754                                 (int)(0.5 + p->score * 100.0/MAX_SCORE),
 755                                 name_munged, other_munged);
 756                 break;
 757         case DIFF_STATUS_RENAMED:
 758                 len += snprintf(msg + len, sizeof(msg) - len,
 759                                 "similarity index %d%%\n"
 760                                 "rename from %s\n"
 761                                 "rename to %s\n",
 762                                 (int)(0.5 + p->score * 100.0/MAX_SCORE),
 763                                 name_munged, other_munged);
 764                 break;
 765         case DIFF_STATUS_MODIFIED:
 766                 if (p->score) {
 767                         len += snprintf(msg + len, sizeof(msg) - len,
 768                                         "dissimilarity index %d%%\n",
 769                                         (int)(0.5 + p->score *
 770                                               100.0/MAX_SCORE));
 771                         complete_rewrite = 1;
 772                         break;
 773                 }
 774                 /* fallthru */
 775         default:
 776                 /* nothing */
 777                 ;
 778         }
 779
 780         if (memcmp(one->sha1, two->sha1, 20)) {
 781                 char one_sha1[41];
 782                 int abbrev = o->full_index ? 40 : DEFAULT_ABBREV;
 783                 memcpy(one_sha1, sha1_to_hex(one->sha1), 41);
 784
 785                 len += snprintf(msg + len, sizeof(msg) - len,
 786                                 "index %.*s..%.*s",
 787                                 abbrev, one_sha1, abbrev,
 788                                 sha1_to_hex(two->sha1));
 789                 if (one->mode == two->mode)
 790                         len += snprintf(msg + len, sizeof(msg) - len,
 791                                         " %06o", one->mode);
 792                 len += snprintf(msg + len, sizeof(msg) - len, "\n");
 793         }
 794
 795         if (len)
 796                 msg[--len] = 0;
 797         xfrm_msg = len ? msg : NULL;
 798
 799         if (!pgm &&
 800             DIFF_FILE_VALID(one) && DIFF_FILE_VALID(two) &&
 801             (S_IFMT & one->mode) != (S_IFMT & two->mode)) {
 802                 /* a filepair that changes between file and symlink
 803                  * needs to be split into deletion and creation.
 804                  */
 805                 struct diff_filespec *null = alloc_filespec(two->path);
 806                 run_diff_cmd(NULL, name, other, one, null, xfrm_msg, 0);
 807                 free(null);
 808                 null = alloc_filespec(one->path);
 809                 run_diff_cmd(NULL, name, other, null, two, xfrm_msg, 0);
 810                 free(null);
 811         }
 812         else
 813                 run_diff_cmd(pgm, name, other, one, two, xfrm_msg,
 814                              complete_rewrite);
 815
 816         free(name_munged);
 817         free(other_munged);
 818 }
 819
 820 void diff_setup(struct diff_options *options)
 821 {
 822         memset(options, 0, sizeof(*options));
 823         options->output_format = DIFF_FORMAT_RAW;
 824         options->line_termination = '\n';
 825         options->break_opt = -1;
 826         options->rename_limit = -1;
 827
 828         options->change = diff_change;
 829         options->add_remove = diff_addremove;
 830 }
 831
 832 int diff_setup_done(struct diff_options *options)
 833 {
 834         if ((options->find_copies_harder &&
 835              options->detect_rename != DIFF_DETECT_COPY) ||
 836             (0 <= options->rename_limit && !options->detect_rename))
 837                 return -1;
 838         if (options->detect_rename && options->rename_limit < 0)
 839                 options->rename_limit = diff_rename_limit_default;
 840         if (options->setup & DIFF_SETUP_USE_CACHE) {
 841                 if (!active_cache)
 842                         /* read-cache does not die even when it fails
 843                          * so it is safe for us to do this here.  Also
 844                          * it does not smudge active_cache or active_nr
 845                          * when it fails, so we do not have to worry about
 846                          * cleaning it up ourselves either.
 847                          */
 848                         read_cache();
 849         }
 850         if (options->setup & DIFF_SETUP_USE_SIZE_CACHE)
 851                 use_size_cache = 1;
 852         if (options->abbrev <= 0 || 40 < options->abbrev)
 853                 options->abbrev = 40; /* full */
 854
 855         return 0;
 856 }
 857
 858 int diff_opt_parse(struct diff_options *options, const char **av, int ac)
 859 {
 860         const char *arg = av[0];
 861         if (!strcmp(arg, "-p") || !strcmp(arg, "-u"))
 862                 options->output_format = DIFF_FORMAT_PATCH;
 863         else if (!strcmp(arg, "-z"))
 864                 options->line_termination = 0;
 865         else if (!strncmp(arg, "-l", 2))
 866                 options->rename_limit = strtoul(arg+2, NULL, 10);
 867         else if (!strcmp(arg, "--full-index"))
 868                 options->full_index = 1;
 869         else if (!strcmp(arg, "--name-only"))
 870                 options->output_format = DIFF_FORMAT_NAME;
 871         else if (!strcmp(arg, "--name-status"))
 872                 options->output_format = DIFF_FORMAT_NAME_STATUS;
 873         else if (!strcmp(arg, "-R"))
 874                 options->reverse_diff = 1;
 875         else if (!strncmp(arg, "-S", 2))
 876                 options->pickaxe = arg + 2;
 877         else if (!strcmp(arg, "-s"))
 878                 options->output_format = DIFF_FORMAT_NO_OUTPUT;
 879         else if (!strncmp(arg, "-O", 2))
 880                 options->orderfile = arg + 2;
 881         else if (!strncmp(arg, "--diff-filter=", 14))
 882                 options->filter = arg + 14;
 883         else if (!strcmp(arg, "--pickaxe-all"))
 884                 options->pickaxe_opts = DIFF_PICKAXE_ALL;
 885         else if (!strncmp(arg, "-B", 2)) {
 886                 if ((options->break_opt =
 887                      diff_scoreopt_parse(arg)) == -1)
 888                         return -1;
 889         }
 890         else if (!strncmp(arg, "-M", 2)) {
 891                 if ((options->rename_score =
 892                      diff_scoreopt_parse(arg)) == -1)
 893                         return -1;
 894                 options->detect_rename = DIFF_DETECT_RENAME;
 895         }
 896         else if (!strncmp(arg, "-C", 2)) {
 897                 if ((options->rename_score =
 898                      diff_scoreopt_parse(arg)) == -1)
 899                         return -1;
 900                 options->detect_rename = DIFF_DETECT_COPY;
 901         }
 902         else if (!strcmp(arg, "--find-copies-harder"))
 903                 options->find_copies_harder = 1;
 904         else if (!strcmp(arg, "--abbrev"))
 905                 options->abbrev = DEFAULT_ABBREV;
 906         else if (!strncmp(arg, "--abbrev=", 9)) {
 907                 options->abbrev = strtoul(arg + 9, NULL, 10);
 908                 if (options->abbrev < MINIMUM_ABBREV)
 909                         options->abbrev = MINIMUM_ABBREV;
 910                 else if (40 < options->abbrev)
 911                         options->abbrev = 40;
 912         }
 913         else
 914                 return 0;
 915         return 1;
 916 }
 917
 918 static int parse_num(const char **cp_p)
 919 {
 920         unsigned long num, scale;
 921         int ch, dot;
 922         const char *cp = *cp_p;
 923
 924         num = 0;
 925         scale = 1;
 926         dot = 0;
 927         for(;;) {
 928                 ch = *cp;
 929                 if ( !dot && ch == '.' ) {
 930                         scale = 1;
 931                         dot = 1;
 932                 } else if ( ch == '%' ) {
 933                         scale = dot ? scale*100 : 100;
 934                         cp++;   /* % is always at the end */
 935                         break;
 936                 } else if ( ch >= '0' && ch <= '9' ) {
 937                         if ( scale < 100000 ) {
 938                                 scale *= 10;
 939                                 num = (num*10) + (ch-'0');
 940                         }
 941                 } else {
 942                         break;
 943                 }
 944                 cp++;
 945         }
 946         *cp_p = cp;
 947
 948         /* user says num divided by scale and we say internally that
 949          * is MAX_SCORE * num / scale.
 950          */
 951         return (num >= scale) ? MAX_SCORE : (MAX_SCORE * num / scale);
 952 }
 953
 954 int diff_scoreopt_parse(const char *opt)
 955 {
 956         int opt1, opt2, cmd;
 957
 958         if (*opt++ != '-')
 959                 return -1;
 960         cmd = *opt++;
 961         if (cmd != 'M' && cmd != 'C' && cmd != 'B')
 962                 return -1; /* that is not a -M, -C nor -B option */
 963
 964         opt1 = parse_num(&opt);
 965         if (cmd != 'B')
 966                 opt2 = 0;
 967         else {
 968                 if (*opt == 0)
 969                         opt2 = 0;
 970                 else if (*opt != '/')
 971                         return -1; /* we expect -B80/99 or -B80 */
 972                 else {
 973                         opt++;
 974                         opt2 = parse_num(&opt);
 975                 }
 976         }
 977         if (*opt != 0)
 978                 return -1;
 979         return opt1 | (opt2 << 16);
 980 }
 981
 982 struct diff_queue_struct diff_queued_diff;
 983
 984 void diff_q(struct diff_queue_struct *queue, struct diff_filepair *dp)
 985 {
 986         if (queue->alloc <= queue->nr) {
 987                 queue->alloc = alloc_nr(queue->alloc);
 988                 queue->queue = xrealloc(queue->queue,
 989                                         sizeof(dp) * queue->alloc);
 990         }
 991         queue->queue[queue->nr++] = dp;
 992 }
 993
 994 struct diff_filepair *diff_queue(struct diff_queue_struct *queue,
 995                                  struct diff_filespec *one,
 996                                  struct diff_filespec *two)
 997 {
 998         struct diff_filepair *dp = xmalloc(sizeof(*dp));
 999         dp->one = one;
1000         dp->two = two;
1001         dp->score = 0;
1002         dp->status = 0;
1003         dp->source_stays = 0;
1004         dp->broken_pair = 0;
1005         if (queue)
1006                 diff_q(queue, dp);
1007         return dp;
1008 }
1009
1010 void diff_free_filepair(struct diff_filepair *p)
1011 {
1012         diff_free_filespec_data(p->one);
1013         diff_free_filespec_data(p->two);
1014         free(p->one);
1015         free(p->two);
1016         free(p);
1017 }
1018
1019 /* This is different from find_unique_abbrev() in that
1020  * it stuffs the result with dots for alignment.
1021  */
1022 const char *diff_unique_abbrev(const unsigned char *sha1, int len)
1023 {
1024         int abblen;
1025         const char *abbrev;
1026         if (len == 40)
1027                 return sha1_to_hex(sha1);
1028
1029         abbrev = find_unique_abbrev(sha1, len);
1030         if (!abbrev)
1031                 return sha1_to_hex(sha1);
1032         abblen = strlen(abbrev);
1033         if (abblen < 37) {
1034                 static char hex[41];
1035                 if (len < abblen && abblen <= len + 2)
1036                         sprintf(hex, "%s%.*s", abbrev, len+3-abblen, "..");
1037                 else
1038                         sprintf(hex, "%s...", abbrev);
1039                 return hex;
1040         }
1041         return sha1_to_hex(sha1);
1042 }
1043
1044 static void diff_flush_raw(struct diff_filepair *p,
1045                            int line_termination,
1046                            int inter_name_termination,
1047                            struct diff_options *options)
1048 {
1049         int two_paths;
1050         char status[10];
1051         int abbrev = options->abbrev;
1052         const char *path_one, *path_two;
1053         int output_format = options->output_format;
1054
1055         path_one = p->one->path;
1056         path_two = p->two->path;
1057         if (line_termination) {
1058                 path_one = quote_one(path_one);
1059                 path_two = quote_one(path_two);
1060         }
1061
1062         if (p->score)
1063                 sprintf(status, "%c%03d", p->status,
1064                         (int)(0.5 + p->score * 100.0/MAX_SCORE));
1065         else {
1066                 status[0] = p->status;
1067                 status[1] = 0;
1068         }
1069         switch (p->status) {
1070         case DIFF_STATUS_COPIED:
1071         case DIFF_STATUS_RENAMED:
1072                 two_paths = 1;
1073                 break;
1074         case DIFF_STATUS_ADDED:
1075         case DIFF_STATUS_DELETED:
1076                 two_paths = 0;
1077                 break;
1078         default:
1079                 two_paths = 0;
1080                 break;
1081         }
1082         if (output_format != DIFF_FORMAT_NAME_STATUS) {
1083                 printf(":%06o %06o %s ",
1084                        p->one->mode, p->two->mode,
1085                        diff_unique_abbrev(p->one->sha1, abbrev));
1086                 printf("%s ",
1087                        diff_unique_abbrev(p->two->sha1, abbrev));
1088         }
1089         printf("%s%c%s", status, inter_name_termination, path_one);
1090         if (two_paths)
1091                 printf("%c%s", inter_name_termination, path_two);
1092         putchar(line_termination);
1093         if (path_one != p->one->path)
1094                 free((void*)path_one);
1095         if (path_two != p->two->path)
1096                 free((void*)path_two);
1097 }
1098
1099 static void diff_flush_name(struct diff_filepair *p,
1100                             int inter_name_termination,
1101                             int line_termination)
1102 {
1103         char *path = p->two->path;
1104
1105         if (line_termination)
1106                 path = quote_one(p->two->path);
1107         else
1108                 path = p->two->path;
1109         printf("%s%c", path, line_termination);
1110         if (p->two->path != path)
1111                 free(path);
1112 }
1113
1114 int diff_unmodified_pair(struct diff_filepair *p)
1115 {
1116         /* This function is written stricter than necessary to support
1117          * the currently implemented transformers, but the idea is to
1118          * let transformers to produce diff_filepairs any way they want,
1119          * and filter and clean them up here before producing the output.
1120          */
1121         struct diff_filespec *one, *two;
1122
1123         if (DIFF_PAIR_UNMERGED(p))
1124                 return 0; /* unmerged is interesting */
1125
1126         one = p->one;
1127         two = p->two;
1128
1129         /* deletion, addition, mode or type change
1130          * and rename are all interesting.
1131          */
1132         if (DIFF_FILE_VALID(one) != DIFF_FILE_VALID(two) ||
1133             DIFF_PAIR_MODE_CHANGED(p) ||
1134             strcmp(one->path, two->path))
1135                 return 0;
1136
1137         /* both are valid and point at the same path.  that is, we are
1138          * dealing with a change.
1139          */
1140         if (one->sha1_valid && two->sha1_valid &&
1141             !memcmp(one->sha1, two->sha1, sizeof(one->sha1)))
1142                 return 1; /* no change */
1143         if (!one->sha1_valid && !two->sha1_valid)
1144                 return 1; /* both look at the same file on the filesystem. */
1145         return 0;
1146 }
1147
1148 static void diff_flush_patch(struct diff_filepair *p, struct diff_options *o)
1149 {
1150         if (diff_unmodified_pair(p))
1151                 return;
1152
1153         if ((DIFF_FILE_VALID(p->one) && S_ISDIR(p->one->mode)) ||
1154             (DIFF_FILE_VALID(p->two) && S_ISDIR(p->two->mode)))
1155                 return; /* no tree diffs in patch format */
1156
1157         run_diff(p, o);
1158 }
1159
1160 int diff_queue_is_empty(void)
1161 {
1162         struct diff_queue_struct *q = &diff_queued_diff;
1163         int i;
1164         for (i = 0; i < q->nr; i++)
1165                 if (!diff_unmodified_pair(q->queue[i]))
1166                         return 0;
1167         return 1;
1168 }
1169
1170 #if DIFF_DEBUG
1171 void diff_debug_filespec(struct diff_filespec *s, int x, const char *one)
1172 {
1173         fprintf(stderr, "queue[%d] %s (%s) %s %06o %s\n",
1174                 x, one ? one : "",
1175                 s->path,
1176                 DIFF_FILE_VALID(s) ? "valid" : "invalid",
1177                 s->mode,
1178                 s->sha1_valid ? sha1_to_hex(s->sha1) : "");
1179         fprintf(stderr, "queue[%d] %s size %lu flags %d\n",
1180                 x, one ? one : "",
1181                 s->size, s->xfrm_flags);
1182 }
1183
1184 void diff_debug_filepair(const struct diff_filepair *p, int i)
1185 {
1186         diff_debug_filespec(p->one, i, "one");
1187         diff_debug_filespec(p->two, i, "two");
1188         fprintf(stderr, "score %d, status %c stays %d broken %d\n",
1189                 p->score, p->status ? p->status : '?',
1190                 p->source_stays, p->broken_pair);
1191 }
1192
1193 void diff_debug_queue(const char *msg, struct diff_queue_struct *q)
1194 {
1195         int i;
1196         if (msg)
1197                 fprintf(stderr, "%s\n", msg);
1198         fprintf(stderr, "q->nr = %d\n", q->nr);
1199         for (i = 0; i < q->nr; i++) {
1200                 struct diff_filepair *p = q->queue[i];
1201                 diff_debug_filepair(p, i);
1202         }
1203 }
1204 #endif
1205
1206 static void diff_resolve_rename_copy(void)
1207 {
1208         int i, j;
1209         struct diff_filepair *p, *pp;
1210         struct diff_queue_struct *q = &diff_queued_diff;
1211
1212         diff_debug_queue("resolve-rename-copy", q);
1213
1214         for (i = 0; i < q->nr; i++) {
1215                 p = q->queue[i];
1216                 p->status = 0; /* undecided */
1217                 if (DIFF_PAIR_UNMERGED(p))
1218                         p->status = DIFF_STATUS_UNMERGED;
1219                 else if (!DIFF_FILE_VALID(p->one))
1220                         p->status = DIFF_STATUS_ADDED;
1221                 else if (!DIFF_FILE_VALID(p->two))
1222                         p->status = DIFF_STATUS_DELETED;
1223                 else if (DIFF_PAIR_TYPE_CHANGED(p))
1224                         p->status = DIFF_STATUS_TYPE_CHANGED;
1225
1226                 /* from this point on, we are dealing with a pair
1227                  * whose both sides are valid and of the same type, i.e.
1228                  * either in-place edit or rename/copy edit.
1229                  */
1230                 else if (DIFF_PAIR_RENAME(p)) {
1231                         if (p->source_stays) {
1232                                 p->status = DIFF_STATUS_COPIED;
1233                                 continue;
1234                         }
1235                         /* See if there is some other filepair that
1236                          * copies from the same source as us.  If so
1237                          * we are a copy.  Otherwise we are either a
1238                          * copy if the path stays, or a rename if it
1239                          * does not, but we already handled "stays" case.
1240                          */
1241                         for (j = i + 1; j < q->nr; j++) {
1242                                 pp = q->queue[j];
1243                                 if (strcmp(pp->one->path, p->one->path))
1244                                         continue; /* not us */
1245                                 if (!DIFF_PAIR_RENAME(pp))
1246                                         continue; /* not a rename/copy */
1247                                 /* pp is a rename/copy from the same source */
1248                                 p->status = DIFF_STATUS_COPIED;
1249                                 break;
1250                         }
1251                         if (!p->status)
1252                                 p->status = DIFF_STATUS_RENAMED;
1253                 }
1254                 else if (memcmp(p->one->sha1, p->two->sha1, 20) ||
1255                          p->one->mode != p->two->mode)
1256                         p->status = DIFF_STATUS_MODIFIED;
1257                 else {
1258                         /* This is a "no-change" entry and should not
1259                          * happen anymore, but prepare for broken callers.
1260                          */
1261                         error("feeding unmodified %s to diffcore",
1262                               p->one->path);
1263                         p->status = DIFF_STATUS_UNKNOWN;
1264                 }
1265         }
1266         diff_debug_queue("resolve-rename-copy done", q);
1267 }
1268
1269 void diff_flush(struct diff_options *options)
1270 {
1271         struct diff_queue_struct *q = &diff_queued_diff;
1272         int i;
1273         int inter_name_termination = '\t';
1274         int diff_output_format = options->output_format;
1275         int line_termination = options->line_termination;
1276
1277         if (!line_termination)
1278                 inter_name_termination = 0;
1279
1280         for (i = 0; i < q->nr; i++) {
1281                 struct diff_filepair *p = q->queue[i];
1282                 if ((diff_output_format == DIFF_FORMAT_NO_OUTPUT) ||
1283                     (p->status == DIFF_STATUS_UNKNOWN))
1284                         continue;
1285                 if (p->status == 0)
1286                         die("internal error in diff-resolve-rename-copy");
1287                 switch (diff_output_format) {
1288                 case DIFF_FORMAT_PATCH:
1289                         diff_flush_patch(p, options);
1290                         break;
1291                 case DIFF_FORMAT_RAW:
1292                 case DIFF_FORMAT_NAME_STATUS:
1293                         diff_flush_raw(p, line_termination,
1294                                        inter_name_termination,
1295                                        options);
1296                         break;
1297                 case DIFF_FORMAT_NAME:
1298                         diff_flush_name(p,
1299                                         inter_name_termination,
1300                                         line_termination);
1301                         break;
1302                 }
1303                 diff_free_filepair(q->queue[i]);
1304         }
1305         free(q->queue);
1306         q->queue = NULL;
1307         q->nr = q->alloc = 0;
1308 }
1309
1310 static void diffcore_apply_filter(const char *filter)
1311 {
1312         int i;
1313         struct diff_queue_struct *q = &diff_queued_diff;
1314         struct diff_queue_struct outq;
1315         outq.queue = NULL;
1316         outq.nr = outq.alloc = 0;
1317
1318         if (!filter)
1319                 return;
1320
1321         if (strchr(filter, DIFF_STATUS_FILTER_AON)) {
1322                 int found;
1323                 for (i = found = 0; !found && i < q->nr; i++) {
1324                         struct diff_filepair *p = q->queue[i];
1325                         if (((p->status == DIFF_STATUS_MODIFIED) &&
1326                              ((p->score &&
1327                                strchr(filter, DIFF_STATUS_FILTER_BROKEN)) ||
1328                               (!p->score &&
1329                                strchr(filter, DIFF_STATUS_MODIFIED)))) ||
1330                             ((p->status != DIFF_STATUS_MODIFIED) &&
1331                              strchr(filter, p->status)))
1332                                 found++;
1333                 }
1334                 if (found)
1335                         return;
1336
1337                 /* otherwise we will clear the whole queue
1338                  * by copying the empty outq at the end of this
1339                  * function, but first clear the current entries
1340                  * in the queue.
1341                  */
1342                 for (i = 0; i < q->nr; i++)
1343                         diff_free_filepair(q->queue[i]);
1344         }
1345         else {
1346                 /* Only the matching ones */
1347                 for (i = 0; i < q->nr; i++) {
1348                         struct diff_filepair *p = q->queue[i];
1349
1350                         if (((p->status == DIFF_STATUS_MODIFIED) &&
1351                              ((p->score &&
1352                                strchr(filter, DIFF_STATUS_FILTER_BROKEN)) ||
1353                               (!p->score &&
1354                                strchr(filter, DIFF_STATUS_MODIFIED)))) ||
1355                             ((p->status != DIFF_STATUS_MODIFIED) &&
1356                              strchr(filter, p->status)))
1357                                 diff_q(&outq, p);
1358                         else
1359                                 diff_free_filepair(p);
1360                 }
1361         }
1362         free(q->queue);
1363         *q = outq;
1364 }
1365
1366 void diffcore_std(struct diff_options *options)
1367 {
1368         if (options->paths && options->paths[0])
1369                 diffcore_pathspec(options->paths);
1370         if (options->break_opt != -1)
1371                 diffcore_break(options->break_opt);
1372         if (options->detect_rename)
1373                 diffcore_rename(options);
1374         if (options->break_opt != -1)
1375                 diffcore_merge_broken();
1376         if (options->pickaxe)
1377                 diffcore_pickaxe(options->pickaxe, options->pickaxe_opts);
1378         if (options->orderfile)
1379                 diffcore_order(options->orderfile);
1380         diff_resolve_rename_copy();
1381         diffcore_apply_filter(options->filter);
1382 }
1383
1384
1385 void diffcore_std_no_resolve(struct diff_options *options)
1386 {
1387         if (options->pickaxe)
1388                 diffcore_pickaxe(options->pickaxe, options->pickaxe_opts);
1389         if (options->orderfile)
1390                 diffcore_order(options->orderfile);
1391         diffcore_apply_filter(options->filter);
1392 }
1393
1394 void diff_addremove(struct diff_options *options,
1395                     int addremove, unsigned mode,
1396                     const unsigned char *sha1,
1397                     const char *base, const char *path)
1398 {
1399         char concatpath[PATH_MAX];
1400         struct diff_filespec *one, *two;
1401
1402         /* This may look odd, but it is a preparation for
1403          * feeding "there are unchanged files which should
1404          * not produce diffs, but when you are doing copy
1405          * detection you would need them, so here they are"
1406          * entries to the diff-core.  They will be prefixed
1407          * with something like '=' or '*' (I haven't decided
1408          * which but should not make any difference).
1409          * Feeding the same new and old to diff_change()
1410          * also has the same effect.
1411          * Before the final output happens, they are pruned after
1412          * merged into rename/copy pairs as appropriate.
1413          */
1414         if (options->reverse_diff)
1415                 addremove = (addremove == '+' ? '-' :
1416                              addremove == '-' ? '+' : addremove);
1417
1418         if (!path) path = "";
1419         sprintf(concatpath, "%s%s", base, path);
1420         one = alloc_filespec(concatpath);
1421         two = alloc_filespec(concatpath);
1422
1423         if (addremove != '+')
1424                 fill_filespec(one, sha1, mode);
1425         if (addremove != '-')
1426                 fill_filespec(two, sha1, mode);
1427
1428         diff_queue(&diff_queued_diff, one, two);
1429 }
1430
1431 void diff_change(struct diff_options *options,
1432                  unsigned old_mode, unsigned new_mode,
1433                  const unsigned char *old_sha1,
1434                  const unsigned char *new_sha1,
1435                  const char *base, const char *path)
1436 {
1437         char concatpath[PATH_MAX];
1438         struct diff_filespec *one, *two;
1439
1440         if (options->reverse_diff) {
1441                 unsigned tmp;
1442                 const unsigned char *tmp_c;
1443                 tmp = old_mode; old_mode = new_mode; new_mode = tmp;
1444                 tmp_c = old_sha1; old_sha1 = new_sha1; new_sha1 = tmp_c;
1445         }
1446         if (!path) path = "";
1447         sprintf(concatpath, "%s%s", base, path);
1448         one = alloc_filespec(concatpath);
1449         two = alloc_filespec(concatpath);
1450         fill_filespec(one, old_sha1, old_mode);
1451         fill_filespec(two, new_sha1, new_mode);
1452
1453         diff_queue(&diff_queued_diff, one, two);
1454 }
1455
1456 void diff_unmerge(struct diff_options *options,
1457                   const char *path)
1458 {
1459         struct diff_filespec *one, *two;
1460         one = alloc_filespec(path);
1461         two = alloc_filespec(path);
1462         diff_queue(&diff_queued_diff, one, two);
1463 }