diff-tree.c

   1 #include <ctype.h>
   2 #include "cache.h"
   3 #include "diff.h"
   4 #include "commit.h"
   5
   6 static int show_root_diff = 0;
   7 static int verbose_header = 0;
   8 static int ignore_merges = 1;
   9 static int recursive = 0;
  10 static int show_tree_entry_in_recursive = 0;
  11 static int read_stdin = 0;
  12 static int diff_output_format = DIFF_FORMAT_HUMAN;
  13 static int detect_rename = 0;
  14 static int find_copies_harder = 0;
  15 static int diff_setup_opt = 0;
  16 static int diff_score_opt = 0;
  17 static const char *pickaxe = NULL;
  18 static int pickaxe_opts = 0;
  19 static int diff_break_opt = -1;
  20 static const char *orderfile = NULL;
  21 static const char *header = NULL;
  22 static const char *header_prefix = "";
  23 static enum cmit_fmt commit_format = CMIT_FMT_RAW;
  24
  25 // What paths are we interested in?
  26 static int nr_paths = 0;
  27 static const char **paths = NULL;
  28 static int *pathlens = NULL;
  29
  30 static int diff_tree_sha1(const unsigned char *old, const unsigned char *new, const char *base);
  31
  32 static void update_tree_entry(void **bufp, unsigned long *sizep)
  33 {
  34         void *buf = *bufp;
  35         unsigned long size = *sizep;
  36         int len = strlen(buf) + 1 + 20;
  37
  38         if (size < len)
  39                 die("corrupt tree file");
  40         *bufp = buf + len;
  41         *sizep = size - len;
  42 }
  43
  44 static const unsigned char *extract(void *tree, unsigned long size, const char **pathp, unsigned int *modep)
  45 {
  46         int len = strlen(tree)+1;
  47         const unsigned char *sha1 = tree + len;
  48         const char *path = strchr(tree, ' ');
  49         unsigned int mode;
  50
  51         if (!path || size < len + 20 || sscanf(tree, "%o", &mode) != 1)
  52                 die("corrupt tree file");
  53         *pathp = path+1;
  54         *modep = DIFF_FILE_CANON_MODE(mode);
  55         return sha1;
  56 }
  57
  58 static char *malloc_base(const char *base, const char *path, int pathlen)
  59 {
  60         int baselen = strlen(base);
  61         char *newbase = xmalloc(baselen + pathlen + 2);
  62         memcpy(newbase, base, baselen);
  63         memcpy(newbase + baselen, path, pathlen);
  64         memcpy(newbase + baselen + pathlen, "/", 2);
  65         return newbase;
  66 }
  67
  68 static void show_file(const char *prefix, void *tree, unsigned long size, const char *base);
  69 static void show_tree(const char *prefix, void *tree, unsigned long size, const char *base);
  70
  71 /* A file entry went away or appeared */
  72 static void show_file(const char *prefix, void *tree, unsigned long size, const char *base)
  73 {
  74         unsigned mode;
  75         const char *path;
  76         const unsigned char *sha1 = extract(tree, size, &path, &mode);
  77
  78         if (recursive && S_ISDIR(mode)) {
  79                 char type[20];
  80                 unsigned long size;
  81                 char *newbase = malloc_base(base, path, strlen(path));
  82                 void *tree;
  83
  84                 tree = read_sha1_file(sha1, type, &size);
  85                 if (!tree || strcmp(type, "tree"))
  86                         die("corrupt tree sha %s", sha1_to_hex(sha1));
  87
  88                 show_tree(prefix, tree, size, newbase);
  89
  90                 free(tree);
  91                 free(newbase);
  92                 return;
  93         }
  94
  95         diff_addremove(prefix[0], mode, sha1, base, path);
  96 }
  97
  98 static int compare_tree_entry(void *tree1, unsigned long size1, void *tree2, unsigned long size2, const char *base)
  99 {
 100         unsigned mode1, mode2;
 101         const char *path1, *path2;
 102         const unsigned char *sha1, *sha2;
 103         int cmp, pathlen1, pathlen2;
 104
 105         sha1 = extract(tree1, size1, &path1, &mode1);
 106         sha2 = extract(tree2, size2, &path2, &mode2);
 107
 108         pathlen1 = strlen(path1);
 109         pathlen2 = strlen(path2);
 110         cmp = base_name_compare(path1, pathlen1, mode1, path2, pathlen2, mode2);
 111         if (cmp < 0) {
 112                 show_file("-", tree1, size1, base);
 113                 return -1;
 114         }
 115         if (cmp > 0) {
 116                 show_file("+", tree2, size2, base);
 117                 return 1;
 118         }
 119         if (!find_copies_harder && !memcmp(sha1, sha2, 20) && mode1 == mode2)
 120                 return 0;
 121
 122         /*
 123          * If the filemode has changed to/from a directory from/to a regular
 124          * file, we need to consider it a remove and an add.
 125          */
 126         if (S_ISDIR(mode1) != S_ISDIR(mode2)) {
 127                 show_file("-", tree1, size1, base);
 128                 show_file("+", tree2, size2, base);
 129                 return 0;
 130         }
 131
 132         if (recursive && S_ISDIR(mode1)) {
 133                 int retval;
 134                 char *newbase = malloc_base(base, path1, pathlen1);
 135                 if (show_tree_entry_in_recursive)
 136                         diff_change(mode1, mode2, sha1, sha2, base, path1);
 137                 retval = diff_tree_sha1(sha1, sha2, newbase);
 138                 free(newbase);
 139                 return retval;
 140         }
 141
 142         diff_change(mode1, mode2, sha1, sha2, base, path1);
 143         return 0;
 144 }
 145
 146 static int interesting(void *tree, unsigned long size, const char *base)
 147 {
 148         const char *path;
 149         unsigned mode;
 150         int i;
 151         int baselen, pathlen;
 152
 153         if (!nr_paths)
 154                 return 1;
 155
 156         (void)extract(tree, size, &path, &mode);
 157
 158         pathlen = strlen(path);
 159         baselen = strlen(base);
 160
 161         for (i=0; i < nr_paths; i++) {
 162                 const char *match = paths[i];
 163                 int matchlen = pathlens[i];
 164
 165                 if (baselen >= matchlen) {
 166                         /* If it doesn't match, move along... */
 167                         if (strncmp(base, match, matchlen))
 168                                 continue;
 169
 170                         /* The base is a subdirectory of a path which was specified. */
 171                         return 1;
 172                 }
 173
 174                 /* Does the base match? */
 175                 if (strncmp(base, match, baselen))
 176                         continue;
 177
 178                 match += baselen;
 179                 matchlen -= baselen;
 180
 181                 if (pathlen > matchlen)
 182                         continue;
 183
 184                 if (matchlen > pathlen) {
 185                         if (match[pathlen] != '/')
 186                                 continue;
 187                         if (!S_ISDIR(mode))
 188                                 continue;
 189                 }
 190
 191                 if (strncmp(path, match, pathlen))
 192                         continue;
 193
 194                 return 1;
 195         }
 196         return 0; /* No matches */
 197 }
 198
 199 /* A whole sub-tree went away or appeared */
 200 static void show_tree(const char *prefix, void *tree, unsigned long size, const char *base)
 201 {
 202         while (size) {
 203                 if (find_copies_harder || interesting(tree, size, base))
 204                         show_file(prefix, tree, size, base);
 205                 update_tree_entry(&tree, &size);
 206         }
 207 }
 208
 209 static int diff_tree(void *tree1, unsigned long size1, void *tree2, unsigned long size2, const char *base)
 210 {
 211         while (size1 | size2) {
 212                 if (nr_paths && size1 && !interesting(tree1, size1, base)) {
 213                         update_tree_entry(&tree1, &size1);
 214                         continue;
 215                 }
 216                 if (nr_paths && size2 && !interesting(tree2, size2, base)) {
 217                         update_tree_entry(&tree2, &size2);
 218                         continue;
 219                 }
 220                 if (!size1) {
 221                         show_file("+", tree2, size2, base);
 222                         update_tree_entry(&tree2, &size2);
 223                         continue;
 224                 }
 225                 if (!size2) {
 226                         show_file("-", tree1, size1, base);
 227                         update_tree_entry(&tree1, &size1);
 228                         continue;
 229                 }
 230                 switch (compare_tree_entry(tree1, size1, tree2, size2, base)) {
 231                 case -1:
 232                         update_tree_entry(&tree1, &size1);
 233                         continue;
 234                 case 0:
 235                         update_tree_entry(&tree1, &size1);
 236                         /* Fallthrough */
 237                 case 1:
 238                         update_tree_entry(&tree2, &size2);
 239                         continue;
 240                 }
 241                 die("git-diff-tree: internal error");
 242         }
 243         return 0;
 244 }
 245
 246 static int diff_tree_sha1(const unsigned char *old, const unsigned char *new, const char *base)
 247 {
 248         void *tree1, *tree2;
 249         unsigned long size1, size2;
 250         int retval;
 251
 252         tree1 = read_object_with_reference(old, "tree", &size1, NULL);
 253         if (!tree1)
 254                 die("unable to read source tree (%s)", sha1_to_hex(old));
 255         tree2 = read_object_with_reference(new, "tree", &size2, NULL);
 256         if (!tree2)
 257                 die("unable to read destination tree (%s)", sha1_to_hex(new));
 258         retval = diff_tree(tree1, size1, tree2, size2, base);
 259         free(tree1);
 260         free(tree2);
 261         return retval;
 262 }
 263
 264 static void call_diff_setup(void)
 265 {
 266         diff_setup(diff_setup_opt);
 267 }
 268
 269 static int call_diff_flush(void)
 270 {
 271         diffcore_std(find_copies_harder ? paths : 0,
 272                      detect_rename, diff_score_opt,
 273                      pickaxe, pickaxe_opts,
 274                      diff_break_opt,
 275                      orderfile);
 276         if (diff_queue_is_empty()) {
 277                 diff_flush(DIFF_FORMAT_NO_OUTPUT, 0);
 278                 return 0;
 279         }
 280         if (header) {
 281                 const char *fmt = "%s";
 282                 if (diff_output_format == DIFF_FORMAT_MACHINE)
 283                         fmt = "%s%c";
 284
 285                 printf(fmt, header, 0);
 286                 header = NULL;
 287         }
 288         diff_flush(diff_output_format, 1);
 289         return 1;
 290 }
 291
 292 static int diff_tree_sha1_top(const unsigned char *old,
 293                               const unsigned char *new, const char *base)
 294 {
 295         int ret;
 296
 297         call_diff_setup();
 298         ret = diff_tree_sha1(old, new, base);
 299         call_diff_flush();
 300         return ret;
 301 }
 302
 303 static int diff_root_tree(const unsigned char *new, const char *base)
 304 {
 305         int retval;
 306         void *tree;
 307         unsigned long size;
 308
 309         call_diff_setup();
 310         tree = read_object_with_reference(new, "tree", &size, NULL);
 311         if (!tree)
 312                 die("unable to read root tree (%s)", sha1_to_hex(new));
 313         retval = diff_tree("", 0, tree, size, base);
 314         free(tree);
 315         call_diff_flush();
 316         return retval;
 317 }
 318
 319 static char *generate_header(const char *commit, const char *parent, const char *msg, unsigned long len)
 320 {
 321         static char this_header[16384];
 322         int offset;
 323
 324         offset = sprintf(this_header, "%s%s (from %s)\n", header_prefix, commit, parent);
 325         if (verbose_header) {
 326                 offset += pretty_print_commit(commit_format, msg, len, this_header + offset, sizeof(this_header) - offset);
 327                 this_header[offset++] = '\n';
 328                 this_header[offset++] = 0;
 329         }
 330
 331         return this_header;
 332 }
 333
 334 static int diff_tree_commit(const unsigned char *commit, const char *name)
 335 {
 336         unsigned long size, offset;
 337         char *buf = read_object_with_reference(commit, "commit", &size, NULL);
 338
 339         if (!buf)
 340                 return -1;
 341
 342         if (!name) {
 343                 static char commit_name[60];
 344                 strcpy(commit_name, sha1_to_hex(commit));
 345                 name = commit_name;
 346         }
 347
 348         /* Root commit? */
 349         if (show_root_diff && memcmp(buf + 46, "parent ", 7)) {
 350                 header = generate_header(name, "root", buf, size);
 351                 diff_root_tree(commit, "");
 352         }
 353
 354         /* More than one parent? */
 355         if (ignore_merges) {
 356                 if (!memcmp(buf + 46 + 48, "parent ", 7))
 357                         return 0;
 358         }
 359
 360         offset = 46;
 361         while (offset + 48 < size && !memcmp(buf + offset, "parent ", 7)) {
 362                 unsigned char parent[20];
 363                 if (get_sha1_hex(buf + offset + 7, parent))
 364                         return -1;
 365                 header = generate_header(name, sha1_to_hex(parent), buf, size);
 366                 diff_tree_sha1_top(parent, commit, "");
 367                 if (!header && verbose_header) {
 368                         header_prefix = "\ndiff-tree ";
 369                         /*
 370                          * Don't print multiple merge entries if we
 371                          * don't print the diffs.
 372                          */
 373                 }
 374                 offset += 48;
 375         }
 376         return 0;
 377 }
 378
 379 static int diff_tree_stdin(char *line)
 380 {
 381         int len = strlen(line);
 382         unsigned char commit[20], parent[20];
 383         static char this_header[1000];
 384
 385         if (!len || line[len-1] != '\n')
 386                 return -1;
 387         line[len-1] = 0;
 388         if (get_sha1_hex(line, commit))
 389                 return -1;
 390         if (isspace(line[40]) && !get_sha1_hex(line+41, parent)) {
 391                 line[40] = 0;
 392                 line[81] = 0;
 393                 sprintf(this_header, "%s (from %s)\n", line, line+41);
 394                 header = this_header;
 395                 return diff_tree_sha1_top(parent, commit, "");
 396         }
 397         line[40] = 0;
 398         return diff_tree_commit(commit, line);
 399 }
 400
 401 static char *diff_tree_usage =
 402 "git-diff-tree [-p] [-r] [-z] [--stdin] [-M] [-C] [-R] [-S<string>] [-O<orderfile>] [-m] [-s] [-v] [--pretty] [-t] <tree-ish> <tree-ish>";
 403
 404 static enum cmit_fmt get_commit_format(const char *arg)
 405 {
 406         if (!*arg)
 407                 return CMIT_FMT_DEFAULT;
 408         if (!strcmp(arg, "=raw"))
 409                 return CMIT_FMT_RAW;
 410         if (!strcmp(arg, "=medium"))
 411                 return CMIT_FMT_MEDIUM;
 412         if (!strcmp(arg, "=short"))
 413                 return CMIT_FMT_SHORT;
 414         usage(diff_tree_usage);
 415 }
 416
 417 int main(int argc, const char **argv)
 418 {
 419         int nr_sha1;
 420         char line[1000];
 421         unsigned char sha1[2][20];
 422
 423         nr_sha1 = 0;
 424         for (;;) {
 425                 const char *arg;
 426
 427                 argv++;
 428                 argc--;
 429                 arg = *argv;
 430                 if (!arg)
 431                         break;
 432
 433                 if (*arg != '-') {
 434                         if (nr_sha1 < 2 && !get_sha1(arg, sha1[nr_sha1])) {
 435                                 nr_sha1++;
 436                                 continue;
 437                         }
 438                         break;
 439                 }
 440
 441                 if (!strcmp(arg, "--")) {
 442                         argv++;
 443                         argc--;
 444                         break;
 445                 }
 446                 if (!strcmp(arg, "-r")) {
 447                         recursive = 1;
 448                         continue;
 449                 }
 450                 if (!strcmp(arg, "-t")) {
 451                         recursive = show_tree_entry_in_recursive = 1;
 452                         continue;
 453                 }
 454                 if (!strcmp(arg, "-R")) {
 455                         diff_setup_opt |= DIFF_SETUP_REVERSE;
 456                         continue;
 457                 }
 458                 if (!strcmp(arg, "-p")) {
 459                         diff_output_format = DIFF_FORMAT_PATCH;
 460                         recursive = 1;
 461                         continue;
 462                 }
 463                 if (!strncmp(arg, "-S", 2)) {
 464                         pickaxe = arg + 2;
 465                         continue;
 466                 }
 467                 if (!strncmp(arg, "-O", 2)) {
 468                         orderfile = arg + 2;
 469                         continue;
 470                 }
 471                 if (!strcmp(arg, "--pickaxe-all")) {
 472                         pickaxe_opts = DIFF_PICKAXE_ALL;
 473                         continue;
 474                 }
 475                 if (!strncmp(arg, "-M", 2)) {
 476                         detect_rename = DIFF_DETECT_RENAME;
 477                         if ((diff_score_opt = diff_scoreopt_parse(arg)) == -1)
 478                                 usage(diff_tree_usage);
 479                         continue;
 480                 }
 481                 if (!strncmp(arg, "-C", 2)) {
 482                         detect_rename = DIFF_DETECT_COPY;
 483                         if ((diff_score_opt = diff_scoreopt_parse(arg)) == -1)
 484                                 usage(diff_tree_usage);
 485                         continue;
 486                 }
 487                 if (!strncmp(arg, "-B", 2)) {
 488                         if ((diff_break_opt = diff_scoreopt_parse(arg)) == -1)
 489                                 usage(diff_tree_usage);
 490                         continue;
 491                 }
 492                 if (!strcmp(arg, "--find-copies-harder")) {
 493                         find_copies_harder = 1;
 494                         continue;
 495                 }
 496                 if (!strcmp(arg, "-z")) {
 497                         diff_output_format = DIFF_FORMAT_MACHINE;
 498                         continue;
 499                 }
 500                 if (!strcmp(arg, "-m")) {
 501                         ignore_merges = 0;
 502                         continue;
 503                 }
 504                 if (!strcmp(arg, "-s")) {
 505                         diff_output_format = DIFF_FORMAT_NO_OUTPUT;
 506                         continue;
 507                 }
 508                 if (!strcmp(arg, "-v")) {
 509                         verbose_header = 1;
 510                         header_prefix = "diff-tree ";
 511                         continue;
 512                 }
 513                 if (!strncmp(arg, "--pretty", 8)) {
 514                         verbose_header = 1;
 515                         header_prefix = "diff-tree ";
 516                         commit_format = get_commit_format(arg+8);
 517                         continue;
 518                 }
 519                 if (!strcmp(arg, "--stdin")) {
 520                         read_stdin = 1;
 521                         continue;
 522                 }
 523                 if (!strcmp(arg, "--root")) {
 524                         show_root_diff = 1;
 525                         continue;
 526                 }
 527                 usage(diff_tree_usage);
 528         }
 529         if (find_copies_harder && detect_rename != DIFF_DETECT_COPY)
 530                 usage(diff_tree_usage);
 531
 532         if (argc > 0) {
 533                 int i;
 534
 535                 paths = argv;
 536                 nr_paths = argc;
 537                 pathlens = xmalloc(nr_paths * sizeof(int));
 538                 for (i=0; i<nr_paths; i++)
 539                         pathlens[i] = strlen(paths[i]);
 540         }
 541
 542         switch (nr_sha1) {
 543         case 0:
 544                 if (!read_stdin)
 545                         usage(diff_tree_usage);
 546                 break;
 547         case 1:
 548                 diff_tree_commit(sha1[0], NULL);
 549                 break;
 550         case 2:
 551                 diff_tree_sha1_top(sha1[0], sha1[1], "");
 552                 break;
 553         }
 554
 555         if (!read_stdin)
 556                 return 0;
 557
 558         if (detect_rename)
 559                 diff_setup_opt |= (DIFF_SETUP_USE_SIZE_CACHE |
 560                                    DIFF_SETUP_USE_CACHE);
 561         while (fgets(line, sizeof(line), stdin))
 562                 diff_tree_stdin(line);
 563
 564         return 0;
 565 }