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 *diff_filter = NULL;
  22 static const char *header = NULL;
  23 static const char *header_prefix = "";
  24 static enum cmit_fmt commit_format = CMIT_FMT_RAW;
  25
  26 // What paths are we interested in?
  27 static int nr_paths = 0;
  28 static const char **paths = NULL;
  29 static int *pathlens = NULL;
  30
  31 static int diff_tree_sha1(const unsigned char *old, const unsigned char *new, const char *base);
  32
  33 static void update_tree_entry(void **bufp, unsigned long *sizep)
  34 {
  35         void *buf = *bufp;
  36         unsigned long size = *sizep;
  37         int len = strlen(buf) + 1 + 20;
  38
  39         if (size < len)
  40                 die("corrupt tree file");
  41         *bufp = buf + len;
  42         *sizep = size - len;
  43 }
  44
  45 static const unsigned char *extract(void *tree, unsigned long size, const char **pathp, unsigned int *modep)
  46 {
  47         int len = strlen(tree)+1;
  48         const unsigned char *sha1 = tree + len;
  49         const char *path = strchr(tree, ' ');
  50         unsigned int mode;
  51
  52         if (!path || size < len + 20 || sscanf(tree, "%o", &mode) != 1)
  53                 die("corrupt tree file");
  54         *pathp = path+1;
  55         *modep = DIFF_FILE_CANON_MODE(mode);
  56         return sha1;
  57 }
  58
  59 static char *malloc_base(const char *base, const char *path, int pathlen)
  60 {
  61         int baselen = strlen(base);
  62         char *newbase = xmalloc(baselen + pathlen + 2);
  63         memcpy(newbase, base, baselen);
  64         memcpy(newbase + baselen, path, pathlen);
  65         memcpy(newbase + baselen + pathlen, "/", 2);
  66         return newbase;
  67 }
  68
  69 static void show_file(const char *prefix, void *tree, unsigned long size, const char *base);
  70 static void show_tree(const char *prefix, void *tree, unsigned long size, const char *base);
  71
  72 /* A file entry went away or appeared */
  73 static void show_file(const char *prefix, void *tree, unsigned long size, const char *base)
  74 {
  75         unsigned mode;
  76         const char *path;
  77         const unsigned char *sha1 = extract(tree, size, &path, &mode);
  78
  79         if (recursive && S_ISDIR(mode)) {
  80                 char type[20];
  81                 unsigned long size;
  82                 char *newbase = malloc_base(base, path, strlen(path));
  83                 void *tree;
  84
  85                 tree = read_sha1_file(sha1, type, &size);
  86                 if (!tree || strcmp(type, "tree"))
  87                         die("corrupt tree sha %s", sha1_to_hex(sha1));
  88
  89                 show_tree(prefix, tree, size, newbase);
  90
  91                 free(tree);
  92                 free(newbase);
  93                 return;
  94         }
  95
  96         diff_addremove(prefix[0], mode, sha1, base, path);
  97 }
  98
  99 static int compare_tree_entry(void *tree1, unsigned long size1, void *tree2, unsigned long size2, const char *base)
 100 {
 101         unsigned mode1, mode2;
 102         const char *path1, *path2;
 103         const unsigned char *sha1, *sha2;
 104         int cmp, pathlen1, pathlen2;
 105
 106         sha1 = extract(tree1, size1, &path1, &mode1);
 107         sha2 = extract(tree2, size2, &path2, &mode2);
 108
 109         pathlen1 = strlen(path1);
 110         pathlen2 = strlen(path2);
 111         cmp = base_name_compare(path1, pathlen1, mode1, path2, pathlen2, mode2);
 112         if (cmp < 0) {
 113                 show_file("-", tree1, size1, base);
 114                 return -1;
 115         }
 116         if (cmp > 0) {
 117                 show_file("+", tree2, size2, base);
 118                 return 1;
 119         }
 120         if (!find_copies_harder && !memcmp(sha1, sha2, 20) && mode1 == mode2)
 121                 return 0;
 122
 123         /*
 124          * If the filemode has changed to/from a directory from/to a regular
 125          * file, we need to consider it a remove and an add.
 126          */
 127         if (S_ISDIR(mode1) != S_ISDIR(mode2)) {
 128                 show_file("-", tree1, size1, base);
 129                 show_file("+", tree2, size2, base);
 130                 return 0;
 131         }
 132
 133         if (recursive && S_ISDIR(mode1)) {
 134                 int retval;
 135                 char *newbase = malloc_base(base, path1, pathlen1);
 136                 if (show_tree_entry_in_recursive)
 137                         diff_change(mode1, mode2, sha1, sha2, base, path1);
 138                 retval = diff_tree_sha1(sha1, sha2, newbase);
 139                 free(newbase);
 140                 return retval;
 141         }
 142
 143         diff_change(mode1, mode2, sha1, sha2, base, path1);
 144         return 0;
 145 }
 146
 147 static int interesting(void *tree, unsigned long size, const char *base)
 148 {
 149         const char *path;
 150         unsigned mode;
 151         int i;
 152         int baselen, pathlen;
 153
 154         if (!nr_paths)
 155                 return 1;
 156
 157         (void)extract(tree, size, &path, &mode);
 158
 159         pathlen = strlen(path);
 160         baselen = strlen(base);
 161
 162         for (i=0; i < nr_paths; i++) {
 163                 const char *match = paths[i];
 164                 int matchlen = pathlens[i];
 165
 166                 if (baselen >= matchlen) {
 167                         /* If it doesn't match, move along... */
 168                         if (strncmp(base, match, matchlen))
 169                                 continue;
 170
 171                         /* The base is a subdirectory of a path which was specified. */
 172                         return 1;
 173                 }
 174
 175                 /* Does the base match? */
 176                 if (strncmp(base, match, baselen))
 177                         continue;
 178
 179                 match += baselen;
 180                 matchlen -= baselen;
 181
 182                 if (pathlen > matchlen)
 183                         continue;
 184
 185                 if (matchlen > pathlen) {
 186                         if (match[pathlen] != '/')
 187                                 continue;
 188                         if (!S_ISDIR(mode))
 189                                 continue;
 190                 }
 191
 192                 if (strncmp(path, match, pathlen))
 193                         continue;
 194
 195                 return 1;
 196         }
 197         return 0; /* No matches */
 198 }
 199
 200 /* A whole sub-tree went away or appeared */
 201 static void show_tree(const char *prefix, void *tree, unsigned long size, const char *base)
 202 {
 203         while (size) {
 204                 if (find_copies_harder || interesting(tree, size, base))
 205                         show_file(prefix, tree, size, base);
 206                 update_tree_entry(&tree, &size);
 207         }
 208 }
 209
 210 static int diff_tree(void *tree1, unsigned long size1, void *tree2, unsigned long size2, const char *base)
 211 {
 212         while (size1 | size2) {
 213                 if (nr_paths && size1 && !interesting(tree1, size1, base)) {
 214                         update_tree_entry(&tree1, &size1);
 215                         continue;
 216                 }
 217                 if (nr_paths && size2 && !interesting(tree2, size2, base)) {
 218                         update_tree_entry(&tree2, &size2);
 219                         continue;
 220                 }
 221                 if (!size1) {
 222                         show_file("+", tree2, size2, base);
 223                         update_tree_entry(&tree2, &size2);
 224                         continue;
 225                 }
 226                 if (!size2) {
 227                         show_file("-", tree1, size1, base);
 228                         update_tree_entry(&tree1, &size1);
 229                         continue;
 230                 }
 231                 switch (compare_tree_entry(tree1, size1, tree2, size2, base)) {
 232                 case -1:
 233                         update_tree_entry(&tree1, &size1);
 234                         continue;
 235                 case 0:
 236                         update_tree_entry(&tree1, &size1);
 237                         /* Fallthrough */
 238                 case 1:
 239                         update_tree_entry(&tree2, &size2);
 240                         continue;
 241                 }
 242                 die("git-diff-tree: internal error");
 243         }
 244         return 0;
 245 }
 246
 247 static int diff_tree_sha1(const unsigned char *old, const unsigned char *new, const char *base)
 248 {
 249         void *tree1, *tree2;
 250         unsigned long size1, size2;
 251         int retval;
 252
 253         tree1 = read_object_with_reference(old, "tree", &size1, NULL);
 254         if (!tree1)
 255                 die("unable to read source tree (%s)", sha1_to_hex(old));
 256         tree2 = read_object_with_reference(new, "tree", &size2, NULL);
 257         if (!tree2)
 258                 die("unable to read destination tree (%s)", sha1_to_hex(new));
 259         retval = diff_tree(tree1, size1, tree2, size2, base);
 260         free(tree1);
 261         free(tree2);
 262         return retval;
 263 }
 264
 265 static void call_diff_setup(void)
 266 {
 267         diff_setup(diff_setup_opt);
 268 }
 269
 270 static int call_diff_flush(void)
 271 {
 272         diffcore_std(find_copies_harder ? paths : 0,
 273                      detect_rename, diff_score_opt,
 274                      pickaxe, pickaxe_opts,
 275                      diff_break_opt,
 276                      orderfile,
 277                      diff_filter);
 278         if (diff_queue_is_empty()) {
 279                 diff_flush(DIFF_FORMAT_NO_OUTPUT);
 280                 return 0;
 281         }
 282         if (header) {
 283                 const char *fmt = "%s";
 284                 if (diff_output_format == DIFF_FORMAT_MACHINE)
 285                         fmt = "%s%c";
 286
 287                 printf(fmt, header, 0);
 288                 header = NULL;
 289         }
 290         diff_flush(diff_output_format);
 291         return 1;
 292 }
 293
 294 static int diff_tree_sha1_top(const unsigned char *old,
 295                               const unsigned char *new, const char *base)
 296 {
 297         int ret;
 298
 299         call_diff_setup();
 300         ret = diff_tree_sha1(old, new, base);
 301         call_diff_flush();
 302         return ret;
 303 }
 304
 305 static int diff_root_tree(const unsigned char *new, const char *base)
 306 {
 307         int retval;
 308         void *tree;
 309         unsigned long size;
 310
 311         call_diff_setup();
 312         tree = read_object_with_reference(new, "tree", &size, NULL);
 313         if (!tree)
 314                 die("unable to read root tree (%s)", sha1_to_hex(new));
 315         retval = diff_tree("", 0, tree, size, base);
 316         free(tree);
 317         call_diff_flush();
 318         return retval;
 319 }
 320
 321 static char *generate_header(const char *commit, const char *parent, const char *msg, unsigned long len)
 322 {
 323         static char this_header[16384];
 324         int offset;
 325
 326         offset = sprintf(this_header, "%s%s (from %s)\n", header_prefix, commit, parent);
 327         if (verbose_header) {
 328                 offset += pretty_print_commit(commit_format, msg, len, this_header + offset, sizeof(this_header) - offset);
 329                 this_header[offset++] = '\n';
 330                 this_header[offset++] = 0;
 331         }
 332
 333         return this_header;
 334 }
 335
 336 static int diff_tree_commit(const unsigned char *commit, const char *name)
 337 {
 338         unsigned long size, offset;
 339         char *buf = read_object_with_reference(commit, "commit", &size, NULL);
 340
 341         if (!buf)
 342                 return -1;
 343
 344         if (!name) {
 345                 static char commit_name[60];
 346                 strcpy(commit_name, sha1_to_hex(commit));
 347                 name = commit_name;
 348         }
 349
 350         /* Root commit? */
 351         if (show_root_diff && memcmp(buf + 46, "parent ", 7)) {
 352                 header = generate_header(name, "root", buf, size);
 353                 diff_root_tree(commit, "");
 354         }
 355
 356         /* More than one parent? */
 357         if (ignore_merges) {
 358                 if (!memcmp(buf + 46 + 48, "parent ", 7))
 359                         return 0;
 360         }
 361
 362         offset = 46;
 363         while (offset + 48 < size && !memcmp(buf + offset, "parent ", 7)) {
 364                 unsigned char parent[20];
 365                 if (get_sha1_hex(buf + offset + 7, parent))
 366                         return -1;
 367                 header = generate_header(name, sha1_to_hex(parent), buf, size);
 368                 diff_tree_sha1_top(parent, commit, "");
 369                 if (!header && verbose_header) {
 370                         header_prefix = "\ndiff-tree ";
 371                         /*
 372                          * Don't print multiple merge entries if we
 373                          * don't print the diffs.
 374                          */
 375                 }
 376                 offset += 48;
 377         }
 378         return 0;
 379 }
 380
 381 static int diff_tree_stdin(char *line)
 382 {
 383         int len = strlen(line);
 384         unsigned char commit[20], parent[20];
 385         static char this_header[1000];
 386
 387         if (!len || line[len-1] != '\n')
 388                 return -1;
 389         line[len-1] = 0;
 390         if (get_sha1_hex(line, commit))
 391                 return -1;
 392         if (isspace(line[40]) && !get_sha1_hex(line+41, parent)) {
 393                 line[40] = 0;
 394                 line[81] = 0;
 395                 sprintf(this_header, "%s (from %s)\n", line, line+41);
 396                 header = this_header;
 397                 return diff_tree_sha1_top(parent, commit, "");
 398         }
 399         line[40] = 0;
 400         return diff_tree_commit(commit, line);
 401 }
 402
 403 static char *diff_tree_usage =
 404 "git-diff-tree [-p] [-r] [-z] [--stdin] [-M] [-C] [-R] [-S<string>] [-O<orderfile>] [-m] [-s] [-v] [--pretty] [-t] <tree-ish> <tree-ish>";
 405
 406 static enum cmit_fmt get_commit_format(const char *arg)
 407 {
 408         if (!*arg)
 409                 return CMIT_FMT_DEFAULT;
 410         if (!strcmp(arg, "=raw"))
 411                 return CMIT_FMT_RAW;
 412         if (!strcmp(arg, "=medium"))
 413                 return CMIT_FMT_MEDIUM;
 414         if (!strcmp(arg, "=short"))
 415                 return CMIT_FMT_SHORT;
 416         usage(diff_tree_usage);
 417 }
 418
 419 int main(int argc, const char **argv)
 420 {
 421         int nr_sha1;
 422         char line[1000];
 423         unsigned char sha1[2][20];
 424
 425         nr_sha1 = 0;
 426         for (;;) {
 427                 const char *arg;
 428
 429                 argv++;
 430                 argc--;
 431                 arg = *argv;
 432                 if (!arg)
 433                         break;
 434
 435                 if (*arg != '-') {
 436                         if (nr_sha1 < 2 && !get_sha1(arg, sha1[nr_sha1])) {
 437                                 nr_sha1++;
 438                                 continue;
 439                         }
 440                         break;
 441                 }
 442
 443                 if (!strcmp(arg, "--")) {
 444                         argv++;
 445                         argc--;
 446                         break;
 447                 }
 448                 if (!strcmp(arg, "-r")) {
 449                         recursive = 1;
 450                         continue;
 451                 }
 452                 if (!strcmp(arg, "-t")) {
 453                         recursive = show_tree_entry_in_recursive = 1;
 454                         continue;
 455                 }
 456                 if (!strcmp(arg, "-R")) {
 457                         diff_setup_opt |= DIFF_SETUP_REVERSE;
 458                         continue;
 459                 }
 460                 if (!strcmp(arg, "-p")) {
 461                         diff_output_format = DIFF_FORMAT_PATCH;
 462                         recursive = 1;
 463                         continue;
 464                 }
 465                 if (!strncmp(arg, "-S", 2)) {
 466                         pickaxe = arg + 2;
 467                         continue;
 468                 }
 469                 if (!strncmp(arg, "-O", 2)) {
 470                         orderfile = arg + 2;
 471                         continue;
 472                 }
 473                 if (!strncmp(arg, "--diff-filter=", 14)) {
 474                         diff_filter = arg + 14;
 475                         continue;
 476                 }
 477                 if (!strcmp(arg, "--pickaxe-all")) {
 478                         pickaxe_opts = DIFF_PICKAXE_ALL;
 479                         continue;
 480                 }
 481                 if (!strncmp(arg, "-M", 2)) {
 482                         detect_rename = DIFF_DETECT_RENAME;
 483                         if ((diff_score_opt = diff_scoreopt_parse(arg)) == -1)
 484                                 usage(diff_tree_usage);
 485                         continue;
 486                 }
 487                 if (!strncmp(arg, "-C", 2)) {
 488                         detect_rename = DIFF_DETECT_COPY;
 489                         if ((diff_score_opt = diff_scoreopt_parse(arg)) == -1)
 490                                 usage(diff_tree_usage);
 491                         continue;
 492                 }
 493                 if (!strncmp(arg, "-B", 2)) {
 494                         if ((diff_break_opt = diff_scoreopt_parse(arg)) == -1)
 495                                 usage(diff_tree_usage);
 496                         continue;
 497                 }
 498                 if (!strcmp(arg, "--find-copies-harder")) {
 499                         find_copies_harder = 1;
 500                         continue;
 501                 }
 502                 if (!strcmp(arg, "-z")) {
 503                         diff_output_format = DIFF_FORMAT_MACHINE;
 504                         continue;
 505                 }
 506                 if (!strcmp(arg, "-m")) {
 507                         ignore_merges = 0;
 508                         continue;
 509                 }
 510                 if (!strcmp(arg, "-s")) {
 511                         diff_output_format = DIFF_FORMAT_NO_OUTPUT;
 512                         continue;
 513                 }
 514                 if (!strcmp(arg, "-v")) {
 515                         verbose_header = 1;
 516                         header_prefix = "diff-tree ";
 517                         continue;
 518                 }
 519                 if (!strncmp(arg, "--pretty", 8)) {
 520                         verbose_header = 1;
 521                         header_prefix = "diff-tree ";
 522                         commit_format = get_commit_format(arg+8);
 523                         continue;
 524                 }
 525                 if (!strcmp(arg, "--stdin")) {
 526                         read_stdin = 1;
 527                         continue;
 528                 }
 529                 if (!strcmp(arg, "--root")) {
 530                         show_root_diff = 1;
 531                         continue;
 532                 }
 533                 usage(diff_tree_usage);
 534         }
 535         if (find_copies_harder && detect_rename != DIFF_DETECT_COPY)
 536                 usage(diff_tree_usage);
 537
 538         if (argc > 0) {
 539                 int i;
 540
 541                 paths = argv;
 542                 nr_paths = argc;
 543                 pathlens = xmalloc(nr_paths * sizeof(int));
 544                 for (i=0; i<nr_paths; i++)
 545                         pathlens[i] = strlen(paths[i]);
 546         }
 547
 548         switch (nr_sha1) {
 549         case 0:
 550                 if (!read_stdin)
 551                         usage(diff_tree_usage);
 552                 break;
 553         case 1:
 554                 diff_tree_commit(sha1[0], NULL);
 555                 break;
 556         case 2:
 557                 diff_tree_sha1_top(sha1[0], sha1[1], "");
 558                 break;
 559         }
 560
 561         if (!read_stdin)
 562                 return 0;
 563
 564         if (detect_rename)
 565                 diff_setup_opt |= (DIFF_SETUP_USE_SIZE_CACHE |
 566                                    DIFF_SETUP_USE_CACHE);
 567         while (fgets(line, sizeof(line), stdin))
 568                 diff_tree_stdin(line);
 569
 570         return 0;
 571 }