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 }
 488
 489 static void prep_temp_blob(struct diff_tempfile *temp,
 490                            void *blob,
 491                            unsigned long size,
 492                            const unsigned char *sha1,
 493                            int mode)
 494 {
 495         int fd;
 496
 497         fd = git_mkstemp(temp->tmp_path, TEMPFILE_PATH_LEN, ".diff_XXXXXX");
 498         if (fd < 0)
 499                 die("unable to create temp-file");
 500         if (write(fd, blob, size) != size)
 501                 die("unable to write temp-file");
 502         close(fd);
 503         temp->name = temp->tmp_path;
 504         strcpy(temp->hex, sha1_to_hex(sha1));
 505         temp->hex[40] = 0;
 506         sprintf(temp->mode, "%06o", mode);
 507 }
 508
 509 static void prepare_temp_file(const char *name,
 510                               struct diff_tempfile *temp,
 511                               struct diff_filespec *one)
 512 {
 513         if (!DIFF_FILE_VALID(one)) {
 514         not_a_valid_file:
 515                 /* A '-' entry produces this for file-2, and
 516                  * a '+' entry produces this for file-1.
 517                  */
 518                 temp->name = "/dev/null";
 519                 strcpy(temp->hex, ".");
 520                 strcpy(temp->mode, ".");
 521                 return;
 522         }
 523
 524         if (!one->sha1_valid ||
 525             work_tree_matches(name, one->sha1)) {
 526                 struct stat st;
 527                 if (lstat(name, &st) < 0) {
 528                         if (errno == ENOENT)
 529                                 goto not_a_valid_file;
 530                         die("stat(%s): %s", name, strerror(errno));
 531                 }
 532                 if (S_ISLNK(st.st_mode)) {
 533                         int ret;
 534                         char buf[PATH_MAX + 1]; /* ought to be SYMLINK_MAX */
 535                         if (sizeof(buf) <= st.st_size)
 536                                 die("symlink too long: %s", name);
 537                         ret = readlink(name, buf, st.st_size);
 538                         if (ret < 0)
 539                                 die("readlink(%s)", name);
 540                         prep_temp_blob(temp, buf, st.st_size,
 541                                        (one->sha1_valid ?
 542                                         one->sha1 : null_sha1),
 543                                        (one->sha1_valid ?
 544                                         one->mode : S_IFLNK));
 545                 }
 546                 else {
 547                         /* we can borrow from the file in the work tree */
 548                         temp->name = name;
 549                         if (!one->sha1_valid)
 550                                 strcpy(temp->hex, sha1_to_hex(null_sha1));
 551                         else
 552                                 strcpy(temp->hex, sha1_to_hex(one->sha1));
 553                         /* Even though we may sometimes borrow the
 554                          * contents from the work tree, we always want
 555                          * one->mode.  mode is trustworthy even when
 556                          * !(one->sha1_valid), as long as
 557                          * DIFF_FILE_VALID(one).
 558                          */
 559                         sprintf(temp->mode, "%06o", one->mode);
 560                 }
 561                 return;
 562         }
 563         else {
 564                 if (diff_populate_filespec(one, 0))
 565                         die("cannot read data blob for %s", one->path);
 566                 prep_temp_blob(temp, one->data, one->size,
 567                                one->sha1, one->mode);
 568         }
 569 }
 570
 571 static void remove_tempfile(void)
 572 {
 573         int i;
 574
 575         for (i = 0; i < 2; i++)
 576                 if (diff_temp[i].name == diff_temp[i].tmp_path) {
 577                         unlink(diff_temp[i].name);
 578                         diff_temp[i].name = NULL;
 579                 }
 580 }
 581
 582 static void remove_tempfile_on_signal(int signo)
 583 {
 584         remove_tempfile();
 585         signal(SIGINT, SIG_DFL);
 586         raise(signo);
 587 }
 588
 589 static int spawn_prog(const char *pgm, const char **arg)
 590 {
 591         pid_t pid;
 592         int status;
 593
 594         fflush(NULL);
 595         pid = fork();
 596         if (pid < 0)
 597                 die("unable to fork");
 598         if (!pid) {
 599                 execvp(pgm, (char *const*) arg);
 600                 exit(255);
 601         }
 602
 603         while (waitpid(pid, &status, 0) < 0) {
 604                 if (errno == EINTR)
 605                         continue;
 606                 return -1;
 607         }
 608
 609         /* Earlier we did not check the exit status because
 610          * diff exits non-zero if files are different, and
 611          * we are not interested in knowing that.  It was a
 612          * mistake which made it harder to quit a diff-*
 613          * session that uses the git-apply-patch-script as
 614          * the GIT_EXTERNAL_DIFF.  A custom GIT_EXTERNAL_DIFF
 615          * should also exit non-zero only when it wants to
 616          * abort the entire diff-* session.
 617          */
 618         if (WIFEXITED(status) && !WEXITSTATUS(status))
 619                 return 0;
 620         return -1;
 621 }
 622
 623 /* An external diff command takes:
 624  *
 625  * diff-cmd name infile1 infile1-sha1 infile1-mode \
 626  *               infile2 infile2-sha1 infile2-mode [ rename-to ]
 627  *
 628  */
 629 static void run_external_diff(const char *pgm,
 630                               const char *name,
 631                               const char *other,
 632                               struct diff_filespec *one,
 633                               struct diff_filespec *two,
 634                               const char *xfrm_msg,
 635                               int complete_rewrite)
 636 {
 637         const char *spawn_arg[10];
 638         struct diff_tempfile *temp = diff_temp;
 639         int retval;
 640         static int atexit_asked = 0;
 641         const char *othername;
 642         const char **arg = &spawn_arg[0];
 643
 644         othername = (other? other : name);
 645         if (one && two) {
 646                 prepare_temp_file(name, &temp[0], one);
 647                 prepare_temp_file(othername, &temp[1], two);
 648                 if (! atexit_asked &&
 649                     (temp[0].name == temp[0].tmp_path ||
 650                      temp[1].name == temp[1].tmp_path)) {
 651                         atexit_asked = 1;
 652                         atexit(remove_tempfile);
 653                 }
 654                 signal(SIGINT, remove_tempfile_on_signal);
 655         }
 656
 657         if (one && two) {
 658                 *arg++ = pgm;
 659                 *arg++ = name;
 660                 *arg++ = temp[0].name;
 661                 *arg++ = temp[0].hex;
 662                 *arg++ = temp[0].mode;
 663                 *arg++ = temp[1].name;
 664                 *arg++ = temp[1].hex;
 665                 *arg++ = temp[1].mode;
 666                 if (other) {
 667                         *arg++ = other;
 668                         *arg++ = xfrm_msg;
 669                 }
 670         } else {
 671                 *arg++ = pgm;
 672                 *arg++ = name;
 673         }
 674         *arg = NULL;
 675         retval = spawn_prog(pgm, spawn_arg);
 676         remove_tempfile();
 677         if (retval) {
 678                 fprintf(stderr, "external diff died, stopping at %s.\n", name);
 679                 exit(1);
 680         }
 681 }
 682
 683 static void run_diff_cmd(const char *pgm,
 684                          const char *name,
 685                          const char *other,
 686                          struct diff_filespec *one,
 687                          struct diff_filespec *two,
 688                          const char *xfrm_msg,
 689                          int complete_rewrite)
 690 {
 691         if (pgm) {
 692                 run_external_diff(pgm, name, other, one, two, xfrm_msg,
 693                                   complete_rewrite);
 694                 return;
 695         }
 696         if (one && two)
 697                 builtin_diff(name, other ? other : name,
 698                              one, two, xfrm_msg, complete_rewrite);
 699         else
 700                 printf("* Unmerged path %s\n", name);
 701 }
 702
 703 static void diff_fill_sha1_info(struct diff_filespec *one)
 704 {
 705         if (DIFF_FILE_VALID(one)) {
 706                 if (!one->sha1_valid) {
 707                         struct stat st;
 708                         if (lstat(one->path, &st) < 0)
 709                                 die("stat %s", one->path);
 710                         if (index_path(one->sha1, one->path, &st, 0))
 711                                 die("cannot hash %s\n", one->path);
 712                 }
 713         }
 714         else
 715                 memset(one->sha1, 0, 20);
 716 }
 717
 718 static void run_diff(struct diff_filepair *p, struct diff_options *o)
 719 {
 720         const char *pgm = external_diff();
 721         char msg[PATH_MAX*2+300], *xfrm_msg;
 722         struct diff_filespec *one;
 723         struct diff_filespec *two;
 724         const char *name;
 725         const char *other;
 726         char *name_munged, *other_munged;
 727         int complete_rewrite = 0;
 728         int len;
 729
 730         if (DIFF_PAIR_UNMERGED(p)) {
 731                 /* unmerged */
 732                 run_diff_cmd(pgm, p->one->path, NULL, NULL, NULL, NULL, 0);
 733                 return;
 734         }
 735
 736         name = p->one->path;
 737         other = (strcmp(name, p->two->path) ? p->two->path : NULL);
 738         name_munged = quote_one(name);
 739         other_munged = quote_one(other);
 740         one = p->one; two = p->two;
 741
 742         diff_fill_sha1_info(one);
 743         diff_fill_sha1_info(two);
 744
 745         len = 0;
 746         switch (p->status) {
 747         case DIFF_STATUS_COPIED:
 748                 len += snprintf(msg + len, sizeof(msg) - len,
 749                                 "similarity index %d%%\n"
 750                                 "copy from %s\n"
 751                                 "copy to %s\n",
 752                                 (int)(0.5 + p->score * 100.0/MAX_SCORE),
 753                                 name_munged, other_munged);
 754                 break;
 755         case DIFF_STATUS_RENAMED:
 756                 len += snprintf(msg + len, sizeof(msg) - len,
 757                                 "similarity index %d%%\n"
 758                                 "rename from %s\n"
 759                                 "rename to %s\n",
 760                                 (int)(0.5 + p->score * 100.0/MAX_SCORE),
 761                                 name_munged, other_munged);
 762                 break;
 763         case DIFF_STATUS_MODIFIED:
 764                 if (p->score) {
 765                         len += snprintf(msg + len, sizeof(msg) - len,
 766                                         "dissimilarity index %d%%\n",
 767                                         (int)(0.5 + p->score *
 768                                               100.0/MAX_SCORE));
 769                         complete_rewrite = 1;
 770                         break;
 771                 }
 772                 /* fallthru */
 773         default:
 774                 /* nothing */
 775                 ;
 776         }
 777
 778         if (memcmp(one->sha1, two->sha1, 20)) {
 779                 char one_sha1[41];
 780                 int abbrev = o->full_index ? 40 : DEFAULT_ABBREV;
 781                 memcpy(one_sha1, sha1_to_hex(one->sha1), 41);
 782
 783                 len += snprintf(msg + len, sizeof(msg) - len,
 784                                 "index %.*s..%.*s",
 785                                 abbrev, one_sha1, abbrev,
 786                                 sha1_to_hex(two->sha1));
 787                 if (one->mode == two->mode)
 788                         len += snprintf(msg + len, sizeof(msg) - len,
 789                                         " %06o", one->mode);
 790                 len += snprintf(msg + len, sizeof(msg) - len, "\n");
 791         }
 792
 793         if (len)
 794                 msg[--len] = 0;
 795         xfrm_msg = len ? msg : NULL;
 796
 797         if (!pgm &&
 798             DIFF_FILE_VALID(one) && DIFF_FILE_VALID(two) &&
 799             (S_IFMT & one->mode) != (S_IFMT & two->mode)) {
 800                 /* a filepair that changes between file and symlink
 801                  * needs to be split into deletion and creation.
 802                  */
 803                 struct diff_filespec *null = alloc_filespec(two->path);
 804                 run_diff_cmd(NULL, name, other, one, null, xfrm_msg, 0);
 805                 free(null);
 806                 null = alloc_filespec(one->path);
 807                 run_diff_cmd(NULL, name, other, null, two, xfrm_msg, 0);
 808                 free(null);
 809         }
 810         else
 811                 run_diff_cmd(pgm, name, other, one, two, xfrm_msg,
 812                              complete_rewrite);
 813
 814         free(name_munged);
 815         free(other_munged);
 816 }
 817
 818 void diff_setup(struct diff_options *options)
 819 {
 820         memset(options, 0, sizeof(*options));
 821         options->output_format = DIFF_FORMAT_RAW;
 822         options->line_termination = '\n';
 823         options->break_opt = -1;
 824         options->rename_limit = -1;
 825
 826         options->change = diff_change;
 827         options->add_remove = diff_addremove;
 828 }
 829
 830 int diff_setup_done(struct diff_options *options)
 831 {
 832         if ((options->find_copies_harder &&
 833              options->detect_rename != DIFF_DETECT_COPY) ||
 834             (0 <= options->rename_limit && !options->detect_rename))
 835                 return -1;
 836         if (options->detect_rename && options->rename_limit < 0)
 837                 options->rename_limit = diff_rename_limit_default;
 838         if (options->setup & DIFF_SETUP_USE_CACHE) {
 839                 if (!active_cache)
 840                         /* read-cache does not die even when it fails
 841                          * so it is safe for us to do this here.  Also
 842                          * it does not smudge active_cache or active_nr
 843                          * when it fails, so we do not have to worry about
 844                          * cleaning it up ourselves either.
 845                          */
 846                         read_cache();
 847         }
 848         if (options->setup & DIFF_SETUP_USE_SIZE_CACHE)
 849                 use_size_cache = 1;
 850         if (options->abbrev <= 0 || 40 < options->abbrev)
 851                 options->abbrev = 40; /* full */
 852
 853         return 0;
 854 }
 855
 856 int diff_opt_parse(struct diff_options *options, const char **av, int ac)
 857 {
 858         const char *arg = av[0];
 859         if (!strcmp(arg, "-p") || !strcmp(arg, "-u"))
 860                 options->output_format = DIFF_FORMAT_PATCH;
 861         else if (!strcmp(arg, "-z"))
 862                 options->line_termination = 0;
 863         else if (!strncmp(arg, "-l", 2))
 864                 options->rename_limit = strtoul(arg+2, NULL, 10);
 865         else if (!strcmp(arg, "--full-index"))
 866                 options->full_index = 1;
 867         else if (!strcmp(arg, "--name-only"))
 868                 options->output_format = DIFF_FORMAT_NAME;
 869         else if (!strcmp(arg, "--name-status"))
 870                 options->output_format = DIFF_FORMAT_NAME_STATUS;
 871         else if (!strcmp(arg, "-R"))
 872                 options->reverse_diff = 1;
 873         else if (!strncmp(arg, "-S", 2))
 874                 options->pickaxe = arg + 2;
 875         else if (!strcmp(arg, "-s"))
 876                 options->output_format = DIFF_FORMAT_NO_OUTPUT;
 877         else if (!strncmp(arg, "-O", 2))
 878                 options->orderfile = arg + 2;
 879         else if (!strncmp(arg, "--diff-filter=", 14))
 880                 options->filter = arg + 14;
 881         else if (!strcmp(arg, "--pickaxe-all"))
 882                 options->pickaxe_opts = DIFF_PICKAXE_ALL;
 883         else if (!strncmp(arg, "-B", 2)) {
 884                 if ((options->break_opt =
 885                      diff_scoreopt_parse(arg)) == -1)
 886                         return -1;
 887         }
 888         else if (!strncmp(arg, "-M", 2)) {
 889                 if ((options->rename_score =
 890                      diff_scoreopt_parse(arg)) == -1)
 891                         return -1;
 892                 options->detect_rename = DIFF_DETECT_RENAME;
 893         }
 894         else if (!strncmp(arg, "-C", 2)) {
 895                 if ((options->rename_score =
 896                      diff_scoreopt_parse(arg)) == -1)
 897                         return -1;
 898                 options->detect_rename = DIFF_DETECT_COPY;
 899         }
 900         else if (!strcmp(arg, "--find-copies-harder"))
 901                 options->find_copies_harder = 1;
 902         else if (!strcmp(arg, "--abbrev"))
 903                 options->abbrev = DEFAULT_ABBREV;
 904         else if (!strncmp(arg, "--abbrev=", 9)) {
 905                 options->abbrev = strtoul(arg + 9, NULL, 10);
 906                 if (options->abbrev < MINIMUM_ABBREV)
 907                         options->abbrev = MINIMUM_ABBREV;
 908                 else if (40 < options->abbrev)
 909                         options->abbrev = 40;
 910         }
 911         else
 912                 return 0;
 913         return 1;
 914 }
 915
 916 static int parse_num(const char **cp_p)
 917 {
 918         unsigned long num, scale;
 919         int ch, dot;
 920         const char *cp = *cp_p;
 921
 922         num = 0;
 923         scale = 1;
 924         dot = 0;
 925         for(;;) {
 926                 ch = *cp;
 927                 if ( !dot && ch == '.' ) {
 928                         scale = 1;
 929                         dot = 1;
 930                 } else if ( ch == '%' ) {
 931                         scale = dot ? scale*100 : 100;
 932                         cp++;   /* % is always at the end */
 933                         break;
 934                 } else if ( ch >= '0' && ch <= '9' ) {
 935                         if ( scale < 100000 ) {
 936                                 scale *= 10;
 937                                 num = (num*10) + (ch-'0');
 938                         }
 939                 } else {
 940                         break;
 941                 }
 942                 cp++;
 943         }
 944         *cp_p = cp;
 945
 946         /* user says num divided by scale and we say internally that
 947          * is MAX_SCORE * num / scale.
 948          */
 949         return (num >= scale) ? MAX_SCORE : (MAX_SCORE * num / scale);
 950 }
 951
 952 int diff_scoreopt_parse(const char *opt)
 953 {
 954         int opt1, opt2, cmd;
 955
 956         if (*opt++ != '-')
 957                 return -1;
 958         cmd = *opt++;
 959         if (cmd != 'M' && cmd != 'C' && cmd != 'B')
 960                 return -1; /* that is not a -M, -C nor -B option */
 961
 962         opt1 = parse_num(&opt);
 963         if (cmd != 'B')
 964                 opt2 = 0;
 965         else {
 966                 if (*opt == 0)
 967                         opt2 = 0;
 968                 else if (*opt != '/')
 969                         return -1; /* we expect -B80/99 or -B80 */
 970                 else {
 971                         opt++;
 972                         opt2 = parse_num(&opt);
 973                 }
 974         }
 975         if (*opt != 0)
 976                 return -1;
 977         return opt1 | (opt2 << 16);
 978 }
 979
 980 struct diff_queue_struct diff_queued_diff;
 981
 982 void diff_q(struct diff_queue_struct *queue, struct diff_filepair *dp)
 983 {
 984         if (queue->alloc <= queue->nr) {
 985                 queue->alloc = alloc_nr(queue->alloc);
 986                 queue->queue = xrealloc(queue->queue,
 987                                         sizeof(dp) * queue->alloc);
 988         }
 989         queue->queue[queue->nr++] = dp;
 990 }
 991
 992 struct diff_filepair *diff_queue(struct diff_queue_struct *queue,
 993                                  struct diff_filespec *one,
 994                                  struct diff_filespec *two)
 995 {
 996         struct diff_filepair *dp = xmalloc(sizeof(*dp));
 997         dp->one = one;
 998         dp->two = two;
 999         dp->score = 0;
1000         dp->status = 0;
1001         dp->source_stays = 0;
1002         dp->broken_pair = 0;
1003         if (queue)
1004                 diff_q(queue, dp);
1005         return dp;
1006 }
1007
1008 void diff_free_filepair(struct diff_filepair *p)
1009 {
1010         diff_free_filespec_data(p->one);
1011         diff_free_filespec_data(p->two);
1012         free(p->one);
1013         free(p->two);
1014         free(p);
1015 }
1016
1017 /* This is different from find_unique_abbrev() in that
1018  * it stuffs the result with dots for alignment.
1019  */
1020 const char *diff_unique_abbrev(const unsigned char *sha1, int len)
1021 {
1022         int abblen;
1023         const char *abbrev;
1024         if (len == 40)
1025                 return sha1_to_hex(sha1);
1026
1027         abbrev = find_unique_abbrev(sha1, len);
1028         if (!abbrev)
1029                 return sha1_to_hex(sha1);
1030         abblen = strlen(abbrev);
1031         if (abblen < 37) {
1032                 static char hex[41];
1033                 if (len < abblen && abblen <= len + 2)
1034                         sprintf(hex, "%s%.*s", abbrev, len+3-abblen, "..");
1035                 else
1036                         sprintf(hex, "%s...", abbrev);
1037                 return hex;
1038         }
1039         return sha1_to_hex(sha1);
1040 }
1041
1042 static void diff_flush_raw(struct diff_filepair *p,
1043                            int line_termination,
1044                            int inter_name_termination,
1045                            struct diff_options *options)
1046 {
1047         int two_paths;
1048         char status[10];
1049         int abbrev = options->abbrev;
1050         const char *path_one, *path_two;
1051         int output_format = options->output_format;
1052
1053         path_one = p->one->path;
1054         path_two = p->two->path;
1055         if (line_termination) {
1056                 path_one = quote_one(path_one);
1057                 path_two = quote_one(path_two);
1058         }
1059
1060         if (p->score)
1061                 sprintf(status, "%c%03d", p->status,
1062                         (int)(0.5 + p->score * 100.0/MAX_SCORE));
1063         else {
1064                 status[0] = p->status;
1065                 status[1] = 0;
1066         }
1067         switch (p->status) {
1068         case DIFF_STATUS_COPIED:
1069         case DIFF_STATUS_RENAMED:
1070                 two_paths = 1;
1071                 break;
1072         case DIFF_STATUS_ADDED:
1073         case DIFF_STATUS_DELETED:
1074                 two_paths = 0;
1075                 break;
1076         default:
1077                 two_paths = 0;
1078                 break;
1079         }
1080         if (output_format != DIFF_FORMAT_NAME_STATUS) {
1081                 printf(":%06o %06o %s ",
1082                        p->one->mode, p->two->mode,
1083                        diff_unique_abbrev(p->one->sha1, abbrev));
1084                 printf("%s ",
1085                        diff_unique_abbrev(p->two->sha1, abbrev));
1086         }
1087         printf("%s%c%s", status, inter_name_termination, path_one);
1088         if (two_paths)
1089                 printf("%c%s", inter_name_termination, path_two);
1090         putchar(line_termination);
1091         if (path_one != p->one->path)
1092                 free((void*)path_one);
1093         if (path_two != p->two->path)
1094                 free((void*)path_two);
1095 }
1096
1097 static void diff_flush_name(struct diff_filepair *p,
1098                             int inter_name_termination,
1099                             int line_termination)
1100 {
1101         char *path = p->two->path;
1102
1103         if (line_termination)
1104                 path = quote_one(p->two->path);
1105         else
1106                 path = p->two->path;
1107         printf("%s%c", path, line_termination);
1108         if (p->two->path != path)
1109                 free(path);
1110 }
1111
1112 int diff_unmodified_pair(struct diff_filepair *p)
1113 {
1114         /* This function is written stricter than necessary to support
1115          * the currently implemented transformers, but the idea is to
1116          * let transformers to produce diff_filepairs any way they want,
1117          * and filter and clean them up here before producing the output.
1118          */
1119         struct diff_filespec *one, *two;
1120
1121         if (DIFF_PAIR_UNMERGED(p))
1122                 return 0; /* unmerged is interesting */
1123
1124         one = p->one;
1125         two = p->two;
1126
1127         /* deletion, addition, mode or type change
1128          * and rename are all interesting.
1129          */
1130         if (DIFF_FILE_VALID(one) != DIFF_FILE_VALID(two) ||
1131             DIFF_PAIR_MODE_CHANGED(p) ||
1132             strcmp(one->path, two->path))
1133                 return 0;
1134
1135         /* both are valid and point at the same path.  that is, we are
1136          * dealing with a change.
1137          */
1138         if (one->sha1_valid && two->sha1_valid &&
1139             !memcmp(one->sha1, two->sha1, sizeof(one->sha1)))
1140                 return 1; /* no change */
1141         if (!one->sha1_valid && !two->sha1_valid)
1142                 return 1; /* both look at the same file on the filesystem. */
1143         return 0;
1144 }
1145
1146 static void diff_flush_patch(struct diff_filepair *p, struct diff_options *o)
1147 {
1148         if (diff_unmodified_pair(p))
1149                 return;
1150
1151         if ((DIFF_FILE_VALID(p->one) && S_ISDIR(p->one->mode)) ||
1152             (DIFF_FILE_VALID(p->two) && S_ISDIR(p->two->mode)))
1153                 return; /* no tree diffs in patch format */
1154
1155         run_diff(p, o);
1156 }
1157
1158 int diff_queue_is_empty(void)
1159 {
1160         struct diff_queue_struct *q = &diff_queued_diff;
1161         int i;
1162         for (i = 0; i < q->nr; i++)
1163                 if (!diff_unmodified_pair(q->queue[i]))
1164                         return 0;
1165         return 1;
1166 }
1167
1168 #if DIFF_DEBUG
1169 void diff_debug_filespec(struct diff_filespec *s, int x, const char *one)
1170 {
1171         fprintf(stderr, "queue[%d] %s (%s) %s %06o %s\n",
1172                 x, one ? one : "",
1173                 s->path,
1174                 DIFF_FILE_VALID(s) ? "valid" : "invalid",
1175                 s->mode,
1176                 s->sha1_valid ? sha1_to_hex(s->sha1) : "");
1177         fprintf(stderr, "queue[%d] %s size %lu flags %d\n",
1178                 x, one ? one : "",
1179                 s->size, s->xfrm_flags);
1180 }
1181
1182 void diff_debug_filepair(const struct diff_filepair *p, int i)
1183 {
1184         diff_debug_filespec(p->one, i, "one");
1185         diff_debug_filespec(p->two, i, "two");
1186         fprintf(stderr, "score %d, status %c stays %d broken %d\n",
1187                 p->score, p->status ? p->status : '?',
1188                 p->source_stays, p->broken_pair);
1189 }
1190
1191 void diff_debug_queue(const char *msg, struct diff_queue_struct *q)
1192 {
1193         int i;
1194         if (msg)
1195                 fprintf(stderr, "%s\n", msg);
1196         fprintf(stderr, "q->nr = %d\n", q->nr);
1197         for (i = 0; i < q->nr; i++) {
1198                 struct diff_filepair *p = q->queue[i];
1199                 diff_debug_filepair(p, i);
1200         }
1201 }
1202 #endif
1203
1204 static void diff_resolve_rename_copy(void)
1205 {
1206         int i, j;
1207         struct diff_filepair *p, *pp;
1208         struct diff_queue_struct *q = &diff_queued_diff;
1209
1210         diff_debug_queue("resolve-rename-copy", q);
1211
1212         for (i = 0; i < q->nr; i++) {
1213                 p = q->queue[i];
1214                 p->status = 0; /* undecided */
1215                 if (DIFF_PAIR_UNMERGED(p))
1216                         p->status = DIFF_STATUS_UNMERGED;
1217                 else if (!DIFF_FILE_VALID(p->one))
1218                         p->status = DIFF_STATUS_ADDED;
1219                 else if (!DIFF_FILE_VALID(p->two))
1220                         p->status = DIFF_STATUS_DELETED;
1221                 else if (DIFF_PAIR_TYPE_CHANGED(p))
1222                         p->status = DIFF_STATUS_TYPE_CHANGED;
1223
1224                 /* from this point on, we are dealing with a pair
1225                  * whose both sides are valid and of the same type, i.e.
1226                  * either in-place edit or rename/copy edit.
1227                  */
1228                 else if (DIFF_PAIR_RENAME(p)) {
1229                         if (p->source_stays) {
1230                                 p->status = DIFF_STATUS_COPIED;
1231                                 continue;
1232                         }
1233                         /* See if there is some other filepair that
1234                          * copies from the same source as us.  If so
1235                          * we are a copy.  Otherwise we are either a
1236                          * copy if the path stays, or a rename if it
1237                          * does not, but we already handled "stays" case.
1238                          */
1239                         for (j = i + 1; j < q->nr; j++) {
1240                                 pp = q->queue[j];
1241                                 if (strcmp(pp->one->path, p->one->path))
1242                                         continue; /* not us */
1243                                 if (!DIFF_PAIR_RENAME(pp))
1244                                         continue; /* not a rename/copy */
1245                                 /* pp is a rename/copy from the same source */
1246                                 p->status = DIFF_STATUS_COPIED;
1247                                 break;
1248                         }
1249                         if (!p->status)
1250                                 p->status = DIFF_STATUS_RENAMED;
1251                 }
1252                 else if (memcmp(p->one->sha1, p->two->sha1, 20) ||
1253                          p->one->mode != p->two->mode)
1254                         p->status = DIFF_STATUS_MODIFIED;
1255                 else {
1256                         /* This is a "no-change" entry and should not
1257                          * happen anymore, but prepare for broken callers.
1258                          */
1259                         error("feeding unmodified %s to diffcore",
1260                               p->one->path);
1261                         p->status = DIFF_STATUS_UNKNOWN;
1262                 }
1263         }
1264         diff_debug_queue("resolve-rename-copy done", q);
1265 }
1266
1267 void diff_flush(struct diff_options *options)
1268 {
1269         struct diff_queue_struct *q = &diff_queued_diff;
1270         int i;
1271         int inter_name_termination = '\t';
1272         int diff_output_format = options->output_format;
1273         int line_termination = options->line_termination;
1274
1275         if (!line_termination)
1276                 inter_name_termination = 0;
1277
1278         for (i = 0; i < q->nr; i++) {
1279                 struct diff_filepair *p = q->queue[i];
1280                 if ((diff_output_format == DIFF_FORMAT_NO_OUTPUT) ||
1281                     (p->status == DIFF_STATUS_UNKNOWN))
1282                         continue;
1283                 if (p->status == 0)
1284                         die("internal error in diff-resolve-rename-copy");
1285                 switch (diff_output_format) {
1286                 case DIFF_FORMAT_PATCH:
1287                         diff_flush_patch(p, options);
1288                         break;
1289                 case DIFF_FORMAT_RAW:
1290                 case DIFF_FORMAT_NAME_STATUS:
1291                         diff_flush_raw(p, line_termination,
1292                                        inter_name_termination,
1293                                        options);
1294                         break;
1295                 case DIFF_FORMAT_NAME:
1296                         diff_flush_name(p,
1297                                         inter_name_termination,
1298                                         line_termination);
1299                         break;
1300                 }
1301                 diff_free_filepair(q->queue[i]);
1302         }
1303         free(q->queue);
1304         q->queue = NULL;
1305         q->nr = q->alloc = 0;
1306 }
1307
1308 static void diffcore_apply_filter(const char *filter)
1309 {
1310         int i;
1311         struct diff_queue_struct *q = &diff_queued_diff;
1312         struct diff_queue_struct outq;
1313         outq.queue = NULL;
1314         outq.nr = outq.alloc = 0;
1315
1316         if (!filter)
1317                 return;
1318
1319         if (strchr(filter, DIFF_STATUS_FILTER_AON)) {
1320                 int found;
1321                 for (i = found = 0; !found && i < q->nr; i++) {
1322                         struct diff_filepair *p = q->queue[i];
1323                         if (((p->status == DIFF_STATUS_MODIFIED) &&
1324                              ((p->score &&
1325                                strchr(filter, DIFF_STATUS_FILTER_BROKEN)) ||
1326                               (!p->score &&
1327                                strchr(filter, DIFF_STATUS_MODIFIED)))) ||
1328                             ((p->status != DIFF_STATUS_MODIFIED) &&
1329                              strchr(filter, p->status)))
1330                                 found++;
1331                 }
1332                 if (found)
1333                         return;
1334
1335                 /* otherwise we will clear the whole queue
1336                  * by copying the empty outq at the end of this
1337                  * function, but first clear the current entries
1338                  * in the queue.
1339                  */
1340                 for (i = 0; i < q->nr; i++)
1341                         diff_free_filepair(q->queue[i]);
1342         }
1343         else {
1344                 /* Only the matching ones */
1345                 for (i = 0; i < q->nr; i++) {
1346                         struct diff_filepair *p = q->queue[i];
1347
1348                         if (((p->status == DIFF_STATUS_MODIFIED) &&
1349                              ((p->score &&
1350                                strchr(filter, DIFF_STATUS_FILTER_BROKEN)) ||
1351                               (!p->score &&
1352                                strchr(filter, DIFF_STATUS_MODIFIED)))) ||
1353                             ((p->status != DIFF_STATUS_MODIFIED) &&
1354                              strchr(filter, p->status)))
1355                                 diff_q(&outq, p);
1356                         else
1357                                 diff_free_filepair(p);
1358                 }
1359         }
1360         free(q->queue);
1361         *q = outq;
1362 }
1363
1364 void diffcore_std(struct diff_options *options)
1365 {
1366         if (options->paths && options->paths[0])
1367                 diffcore_pathspec(options->paths);
1368         if (options->break_opt != -1)
1369                 diffcore_break(options->break_opt);
1370         if (options->detect_rename)
1371                 diffcore_rename(options);
1372         if (options->break_opt != -1)
1373                 diffcore_merge_broken();
1374         if (options->pickaxe)
1375                 diffcore_pickaxe(options->pickaxe, options->pickaxe_opts);
1376         if (options->orderfile)
1377                 diffcore_order(options->orderfile);
1378         diff_resolve_rename_copy();
1379         diffcore_apply_filter(options->filter);
1380 }
1381
1382
1383 void diffcore_std_no_resolve(struct diff_options *options)
1384 {
1385         if (options->pickaxe)
1386                 diffcore_pickaxe(options->pickaxe, options->pickaxe_opts);
1387         if (options->orderfile)
1388                 diffcore_order(options->orderfile);
1389         diffcore_apply_filter(options->filter);
1390 }
1391
1392 void diff_addremove(struct diff_options *options,
1393                     int addremove, unsigned mode,
1394                     const unsigned char *sha1,
1395                     const char *base, const char *path)
1396 {
1397         char concatpath[PATH_MAX];
1398         struct diff_filespec *one, *two;
1399
1400         /* This may look odd, but it is a preparation for
1401          * feeding "there are unchanged files which should
1402          * not produce diffs, but when you are doing copy
1403          * detection you would need them, so here they are"
1404          * entries to the diff-core.  They will be prefixed
1405          * with something like '=' or '*' (I haven't decided
1406          * which but should not make any difference).
1407          * Feeding the same new and old to diff_change()
1408          * also has the same effect.
1409          * Before the final output happens, they are pruned after
1410          * merged into rename/copy pairs as appropriate.
1411          */
1412         if (options->reverse_diff)
1413                 addremove = (addremove == '+' ? '-' :
1414                              addremove == '-' ? '+' : addremove);
1415
1416         if (!path) path = "";
1417         sprintf(concatpath, "%s%s", base, path);
1418         one = alloc_filespec(concatpath);
1419         two = alloc_filespec(concatpath);
1420
1421         if (addremove != '+')
1422                 fill_filespec(one, sha1, mode);
1423         if (addremove != '-')
1424                 fill_filespec(two, sha1, mode);
1425
1426         diff_queue(&diff_queued_diff, one, two);
1427 }
1428
1429 void diff_change(struct diff_options *options,
1430                  unsigned old_mode, unsigned new_mode,
1431                  const unsigned char *old_sha1,
1432                  const unsigned char *new_sha1,
1433                  const char *base, const char *path)
1434 {
1435         char concatpath[PATH_MAX];
1436         struct diff_filespec *one, *two;
1437
1438         if (options->reverse_diff) {
1439                 unsigned tmp;
1440                 const unsigned char *tmp_c;
1441                 tmp = old_mode; old_mode = new_mode; new_mode = tmp;
1442                 tmp_c = old_sha1; old_sha1 = new_sha1; new_sha1 = tmp_c;
1443         }
1444         if (!path) path = "";
1445         sprintf(concatpath, "%s%s", base, path);
1446         one = alloc_filespec(concatpath);
1447         two = alloc_filespec(concatpath);
1448         fill_filespec(one, old_sha1, old_mode);
1449         fill_filespec(two, new_sha1, new_mode);
1450
1451         diff_queue(&diff_queued_diff, one, two);
1452 }
1453
1454 void diff_unmerge(struct diff_options *options,
1455                   const char *path)
1456 {
1457         struct diff_filespec *one, *two;
1458         one = alloc_filespec(path);
1459         two = alloc_filespec(path);
1460         diff_queue(&diff_queued_diff, one, two);
1461 }