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_RAW;
  13 static int diff_line_termination = '\n';
  14 static int detect_rename = 0;
  15 static int find_copies_harder = 0;
  16 static int diff_setup_opt = 0;
  17 static int diff_score_opt = 0;
  18 static const char *pickaxe = NULL;
  19 static int pickaxe_opts = 0;
  20 static int diff_break_opt = -1;
  21 static const char *orderfile = NULL;
  22 static const char *diff_filter = NULL;
  23 static const char *header = NULL;
  24 static const char *header_prefix = "";
  25 static enum cmit_fmt commit_format = CMIT_FMT_RAW;
  26
  27 // What paths are we interested in?
  28 static int nr_paths = 0;
  29 static const char **paths = NULL;
  30 static int *pathlens = NULL;
  31
  32 static int diff_tree_sha1(const unsigned char *old, const unsigned char *new, const char *base);
  33
  34 static void update_tree_entry(void **bufp, unsigned long *sizep)
  35 {
  36         void *buf = *bufp;
  37         unsigned long size = *sizep;
  38         int len = strlen(buf) + 1 + 20;
  39
  40         if (size < len)
  41                 die("corrupt tree file");
  42         *bufp = buf + len;
  43         *sizep = size - len;
  44 }
  45
  46 static const unsigned char *extract(void *tree, unsigned long size, const char **pathp, unsigned int *modep)
  47 {
  48         int len = strlen(tree)+1;
  49         const unsigned char *sha1 = tree + len;
  50         const char *path = strchr(tree, ' ');
  51         unsigned int mode;
  52
  53         if (!path || size < len + 20 || sscanf(tree, "%o", &mode) != 1)
  54                 die("corrupt tree file");
  55         *pathp = path+1;
  56         *modep = DIFF_FILE_CANON_MODE(mode);
  57         return sha1;
  58 }
  59
  60 static char *malloc_base(const char *base, const char *path, int pathlen)
  61 {
  62         int baselen = strlen(base);
  63         char *newbase = xmalloc(baselen + pathlen + 2);
  64         memcpy(newbase, base, baselen);
  65         memcpy(newbase + baselen, path, pathlen);
  66         memcpy(newbase + baselen + pathlen, "/", 2);
  67         return newbase;
  68 }
  69
  70 static void show_file(const char *prefix, void *tree, unsigned long size, const char *base);
  71 static void show_tree(const char *prefix, void *tree, unsigned long size, const char *base);
  72
  73 /* A file entry went away or appeared */
  74 static void show_file(const char *prefix, void *tree, unsigned long size, const char *base)
  75 {
  76         unsigned mode;
  77         const char *path;
  78         const unsigned char *sha1 = extract(tree, size, &path, &mode);
  79
  80         if (recursive && S_ISDIR(mode)) {
  81                 char type[20];
  82                 unsigned long size;
  83                 char *newbase = malloc_base(base, path, strlen(path));
  84                 void *tree;
  85
  86                 tree = read_sha1_file(sha1, type, &size);
  87                 if (!tree || strcmp(type, "tree"))
  88                         die("corrupt tree sha %s", sha1_to_hex(sha1));
  89
  90                 show_tree(prefix, tree, size, newbase);
  91
  92                 free(tree);
  93                 free(newbase);
  94                 return;
  95         }
  96
  97         diff_addremove(prefix[0], mode, sha1, base, path);
  98 }
  99
 100 static int compare_tree_entry(void *tree1, unsigned long size1, void *tree2, unsigned long size2, const char *base)
 101 {
 102         unsigned mode1, mode2;
 103         const char *path1, *path2;
 104         const unsigned char *sha1, *sha2;
 105         int cmp, pathlen1, pathlen2;
 106
 107         sha1 = extract(tree1, size1, &path1, &mode1);
 108         sha2 = extract(tree2, size2, &path2, &mode2);
 109
 110         pathlen1 = strlen(path1);
 111         pathlen2 = strlen(path2);
 112         cmp = base_name_compare(path1, pathlen1, mode1, path2, pathlen2, mode2);
 113         if (cmp < 0) {
 114                 show_file("-", tree1, size1, base);
 115                 return -1;
 116         }
 117         if (cmp > 0) {
 118                 show_file("+", tree2, size2, base);
 119                 return 1;
 120         }
 121         if (!find_copies_harder && !memcmp(sha1, sha2, 20) && mode1 == mode2)
 122                 return 0;
 123
 124         /*
 125          * If the filemode has changed to/from a directory from/to a regular
 126          * file, we need to consider it a remove and an add.
 127          */
 128         if (S_ISDIR(mode1) != S_ISDIR(mode2)) {
 129                 show_file("-", tree1, size1, base);
 130                 show_file("+", tree2, size2, base);
 131                 return 0;
 132         }
 133
 134         if (recursive && S_ISDIR(mode1)) {
 135                 int retval;
 136                 char *newbase = malloc_base(base, path1, pathlen1);
 137                 if (show_tree_entry_in_recursive)
 138                         diff_change(mode1, mode2, sha1, sha2, base, path1);
 139                 retval = diff_tree_sha1(sha1, sha2, newbase);
 140                 free(newbase);
 141                 return retval;
 142         }
 143
 144         diff_change(mode1, mode2, sha1, sha2, base, path1);
 145         return 0;
 146 }
 147
 148 static int interesting(void *tree, unsigned long size, const char *base)
 149 {
 150         const char *path;
 151         unsigned mode;
 152         int i;
 153         int baselen, pathlen;
 154
 155         if (!nr_paths)
 156                 return 1;
 157
 158         (void)extract(tree, size, &path, &mode);
 159
 160         pathlen = strlen(path);
 161         baselen = strlen(base);
 162
 163         for (i=0; i < nr_paths; i++) {
 164                 const char *match = paths[i];
 165                 int matchlen = pathlens[i];
 166
 167                 if (baselen >= matchlen) {
 168                         /* If it doesn't match, move along... */
 169                         if (strncmp(base, match, matchlen))
 170                                 continue;
 171
 172                         /* The base is a subdirectory of a path which was specified. */
 173                         return 1;
 174                 }
 175
 176                 /* Does the base match? */
 177                 if (strncmp(base, match, baselen))
 178                         continue;
 179
 180                 match += baselen;
 181                 matchlen -= baselen;
 182
 183                 if (pathlen > matchlen)
 184                         continue;
 185
 186                 if (matchlen > pathlen) {
 187                         if (match[pathlen] != '/')
 188                                 continue;
 189                         if (!S_ISDIR(mode))
 190                                 continue;
 191                 }
 192
 193                 if (strncmp(path, match, pathlen))
 194                         continue;
 195
 196                 return 1;
 197         }
 198         return 0; /* No matches */
 199 }
 200
 201 /* A whole sub-tree went away or appeared */
 202 static void show_tree(const char *prefix, void *tree, unsigned long size, const char *base)
 203 {
 204         while (size) {
 205                 if (interesting(tree, size, base))
 206                         show_file(prefix, tree, size, base);
 207                 update_tree_entry(&tree, &size);
 208         }
 209 }
 210
 211 static int diff_tree(void *tree1, unsigned long size1, void *tree2, unsigned long size2, const char *base)
 212 {
 213         while (size1 | size2) {
 214                 if (nr_paths && size1 && !interesting(tree1, size1, base)) {
 215                         update_tree_entry(&tree1, &size1);
 216                         continue;
 217                 }
 218                 if (nr_paths && size2 && !interesting(tree2, size2, base)) {
 219                         update_tree_entry(&tree2, &size2);
 220                         continue;
 221                 }
 222                 if (!size1) {
 223                         show_file("+", tree2, size2, base);
 224                         update_tree_entry(&tree2, &size2);
 225                         continue;
 226                 }
 227                 if (!size2) {
 228                         show_file("-", tree1, size1, base);
 229                         update_tree_entry(&tree1, &size1);
 230                         continue;
 231                 }
 232                 switch (compare_tree_entry(tree1, size1, tree2, size2, base)) {
 233                 case -1:
 234                         update_tree_entry(&tree1, &size1);
 235                         continue;
 236                 case 0:
 237                         update_tree_entry(&tree1, &size1);
 238                         /* Fallthrough */
 239                 case 1:
 240                         update_tree_entry(&tree2, &size2);
 241                         continue;
 242                 }
 243                 die("git-diff-tree: internal error");
 244         }
 245         return 0;
 246 }
 247
 248 static int diff_tree_sha1(const unsigned char *old, const unsigned char *new, const char *base)
 249 {
 250         void *tree1, *tree2;
 251         unsigned long size1, size2;
 252         int retval;
 253
 254         tree1 = read_object_with_reference(old, "tree", &size1, NULL);
 255         if (!tree1)
 256                 die("unable to read source tree (%s)", sha1_to_hex(old));
 257         tree2 = read_object_with_reference(new, "tree", &size2, NULL);
 258         if (!tree2)
 259                 die("unable to read destination tree (%s)", sha1_to_hex(new));
 260         retval = diff_tree(tree1, size1, tree2, size2, base);
 261         free(tree1);
 262         free(tree2);
 263         return retval;
 264 }
 265
 266 static void call_diff_setup(void)
 267 {
 268         diff_setup(diff_setup_opt);
 269 }
 270
 271 static int call_diff_flush(void)
 272 {
 273         diffcore_std(NULL,
 274                      detect_rename, diff_score_opt,
 275                      pickaxe, pickaxe_opts,
 276                      diff_break_opt,
 277                      orderfile,
 278                      diff_filter);
 279         if (diff_queue_is_empty()) {
 280                 diff_flush(DIFF_FORMAT_NO_OUTPUT, diff_line_termination);
 281                 return 0;
 282         }
 283         if (header) {
 284                 printf("%s%c", header, diff_line_termination);
 285                 header = NULL;
 286         }
 287         diff_flush(diff_output_format, diff_line_termination);
 288         return 1;
 289 }
 290
 291 static int diff_tree_sha1_top(const unsigned char *old,
 292                               const unsigned char *new, const char *base)
 293 {
 294         int ret;
 295
 296         call_diff_setup();
 297         ret = diff_tree_sha1(old, new, base);
 298         call_diff_flush();
 299         return ret;
 300 }
 301
 302 static int diff_root_tree(const unsigned char *new, const char *base)
 303 {
 304         int retval;
 305         void *tree;
 306         unsigned long size;
 307
 308         call_diff_setup();
 309         tree = read_object_with_reference(new, "tree", &size, NULL);
 310         if (!tree)
 311                 die("unable to read root tree (%s)", sha1_to_hex(new));
 312         retval = diff_tree("", 0, tree, size, base);
 313         free(tree);
 314         call_diff_flush();
 315         return retval;
 316 }
 317
 318 static const char *generate_header(const char *commit, const char *parent, const char *msg, unsigned long len)
 319 {
 320         static char this_header[16384];
 321         int offset;
 322
 323         if (!verbose_header)
 324                 return commit;
 325
 326         offset = sprintf(this_header, "%s%s (from %s)\n", header_prefix, commit, parent);
 327         offset += pretty_print_commit(commit_format, msg, len, this_header + offset, sizeof(this_header) - offset);
 328         return this_header;
 329 }
 330
 331 static int diff_tree_commit(const unsigned char *commit, const char *name)
 332 {
 333         unsigned long size, offset;
 334         char *buf = read_object_with_reference(commit, "commit", &size, NULL);
 335
 336         if (!buf)
 337                 return -1;
 338
 339         if (!name) {
 340                 static char commit_name[60];
 341                 strcpy(commit_name, sha1_to_hex(commit));
 342                 name = commit_name;
 343         }
 344
 345         /* Root commit? */
 346         if (show_root_diff && memcmp(buf + 46, "parent ", 7)) {
 347                 header = generate_header(name, "root", buf, size);
 348                 diff_root_tree(commit, "");
 349         }
 350
 351         /* More than one parent? */
 352         if (ignore_merges) {
 353                 if (!memcmp(buf + 46 + 48, "parent ", 7))
 354                         return 0;
 355         }
 356
 357         offset = 46;
 358         while (offset + 48 < size && !memcmp(buf + offset, "parent ", 7)) {
 359                 unsigned char parent[20];
 360                 if (get_sha1_hex(buf + offset + 7, parent))
 361                         return -1;
 362                 header = generate_header(name, sha1_to_hex(parent), buf, size);
 363                 diff_tree_sha1_top(parent, commit, "");
 364                 if (!header && verbose_header) {
 365                         header_prefix = "\ndiff-tree ";
 366                         /*
 367                          * Don't print multiple merge entries if we
 368                          * don't print the diffs.
 369                          */
 370                 }
 371                 offset += 48;
 372         }
 373         free(buf);
 374         return 0;
 375 }
 376
 377 static int diff_tree_stdin(char *line)
 378 {
 379         int len = strlen(line);
 380         unsigned char commit[20], parent[20];
 381         static char this_header[1000];
 382
 383         if (!len || line[len-1] != '\n')
 384                 return -1;
 385         line[len-1] = 0;
 386         if (get_sha1_hex(line, commit))
 387                 return -1;
 388         if (isspace(line[40]) && !get_sha1_hex(line+41, parent)) {
 389                 line[40] = 0;
 390                 line[81] = 0;
 391                 sprintf(this_header, "%s (from %s)\n", line, line+41);
 392                 header = this_header;
 393                 return diff_tree_sha1_top(parent, commit, "");
 394         }
 395         line[40] = 0;
 396         return diff_tree_commit(commit, line);
 397 }
 398
 399 static int count_paths(const char **paths)
 400 {
 401         int i = 0;
 402         while (*paths++)
 403                 i++;
 404         return i;
 405 }
 406
 407 static const char diff_tree_usage[] =
 408 "git-diff-tree [--stdin] [-m] [-s] [-v] [--pretty] [-t] "
 409 "[<common diff options>] <tree-ish> <tree-ish>"
 410 COMMON_DIFF_OPTIONS_HELP;
 411
 412 int main(int argc, char **argv)
 413 {
 414         int nr_sha1;
 415         char line[1000];
 416         unsigned char sha1[2][20];
 417         const char *prefix = setup_git_directory();
 418
 419         nr_sha1 = 0;
 420         for (;;) {
 421                 const char *arg;
 422
 423                 argv++;
 424                 argc--;
 425                 arg = *argv;
 426                 if (!arg)
 427                         break;
 428
 429                 if (*arg != '-') {
 430                         if (nr_sha1 < 2 && !get_sha1(arg, sha1[nr_sha1])) {
 431                                 nr_sha1++;
 432                                 continue;
 433                         }
 434                         break;
 435                 }
 436
 437                 if (!strcmp(arg, "--")) {
 438                         argv++;
 439                         argc--;
 440                         break;
 441                 }
 442                 if (!strcmp(arg, "-r")) {
 443                         recursive = 1;
 444                         continue;
 445                 }
 446                 if (!strcmp(arg, "-t")) {
 447                         recursive = show_tree_entry_in_recursive = 1;
 448                         continue;
 449                 }
 450                 if (!strcmp(arg, "-R")) {
 451                         diff_setup_opt |= DIFF_SETUP_REVERSE;
 452                         continue;
 453                 }
 454                 if (!strcmp(arg, "-p") || !strcmp(arg, "-u")) {
 455                         diff_output_format = DIFF_FORMAT_PATCH;
 456                         recursive = 1;
 457                         continue;
 458                 }
 459                 if (!strncmp(arg, "-S", 2)) {
 460                         pickaxe = arg + 2;
 461                         continue;
 462                 }
 463                 if (!strncmp(arg, "-O", 2)) {
 464                         orderfile = arg + 2;
 465                         continue;
 466                 }
 467                 if (!strncmp(arg, "--diff-filter=", 14)) {
 468                         diff_filter = arg + 14;
 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, "--name-only")) {
 497                         diff_output_format = DIFF_FORMAT_NAME;
 498                         continue;
 499                 }
 500                 if (!strcmp(arg, "-z")) {
 501                         diff_line_termination = 0;
 502                         continue;
 503                 }
 504                 if (!strcmp(arg, "-m")) {
 505                         ignore_merges = 0;
 506                         continue;
 507                 }
 508                 if (!strcmp(arg, "-s")) {
 509                         diff_output_format = DIFF_FORMAT_NO_OUTPUT;
 510                         continue;
 511                 }
 512                 if (!strcmp(arg, "-v")) {
 513                         verbose_header = 1;
 514                         header_prefix = "diff-tree ";
 515                         continue;
 516                 }
 517                 if (!strncmp(arg, "--pretty", 8)) {
 518                         verbose_header = 1;
 519                         header_prefix = "diff-tree ";
 520                         commit_format = get_commit_format(arg+8);
 521                         continue;
 522                 }
 523                 if (!strcmp(arg, "--stdin")) {
 524                         read_stdin = 1;
 525                         continue;
 526                 }
 527                 if (!strcmp(arg, "--root")) {
 528                         show_root_diff = 1;
 529                         continue;
 530                 }
 531                 usage(diff_tree_usage);
 532         }
 533         if (find_copies_harder && detect_rename != DIFF_DETECT_COPY)
 534                 usage(diff_tree_usage);
 535
 536         paths = get_pathspec(prefix, argv);
 537         if (paths) {
 538                 int i;
 539
 540                 nr_paths = count_paths(paths);
 541                 pathlens = xmalloc(nr_paths * sizeof(int));
 542                 for (i=0; i<nr_paths; i++)
 543                         pathlens[i] = strlen(paths[i]);
 544         }
 545
 546         switch (nr_sha1) {
 547         case 0:
 548                 if (!read_stdin)
 549                         usage(diff_tree_usage);
 550                 break;
 551         case 1:
 552                 diff_tree_commit(sha1[0], NULL);
 553                 break;
 554         case 2:
 555                 diff_tree_sha1_top(sha1[0], sha1[1], "");
 556                 break;
 557         }
 558
 559         if (!read_stdin)
 560                 return 0;
 561
 562         if (detect_rename)
 563                 diff_setup_opt |= (DIFF_SETUP_USE_SIZE_CACHE |
 564                                    DIFF_SETUP_USE_CACHE);
 565         while (fgets(line, sizeof(line), stdin))
 566                 diff_tree_stdin(line);
 567
 568         return 0;
 569 }