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 (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(NULL,
 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                 printf("%s%c", header, diff_output_format == DIFF_FORMAT_MACHINE ? 0 : '\n');
 284                 header = NULL;
 285         }
 286         diff_flush(diff_output_format);
 287         return 1;
 288 }
 289
 290 static int diff_tree_sha1_top(const unsigned char *old,
 291                               const unsigned char *new, const char *base)
 292 {
 293         int ret;
 294
 295         call_diff_setup();
 296         ret = diff_tree_sha1(old, new, base);
 297         call_diff_flush();
 298         return ret;
 299 }
 300
 301 static int diff_root_tree(const unsigned char *new, const char *base)
 302 {
 303         int retval;
 304         void *tree;
 305         unsigned long size;
 306
 307         call_diff_setup();
 308         tree = read_object_with_reference(new, "tree", &size, NULL);
 309         if (!tree)
 310                 die("unable to read root tree (%s)", sha1_to_hex(new));
 311         retval = diff_tree("", 0, tree, size, base);
 312         free(tree);
 313         call_diff_flush();
 314         return retval;
 315 }
 316
 317 static const char *generate_header(const char *commit, const char *parent, const char *msg, unsigned long len)
 318 {
 319         static char this_header[16384];
 320         int offset;
 321
 322         if (!verbose_header)
 323                 return commit;
 324
 325         offset = sprintf(this_header, "%s%s (from %s)\n", header_prefix, commit, parent);
 326         offset += pretty_print_commit(commit_format, msg, len, this_header + offset, sizeof(this_header) - offset);
 327         return this_header;
 328 }
 329
 330 static int diff_tree_commit(const unsigned char *commit, const char *name)
 331 {
 332         unsigned long size, offset;
 333         char *buf = read_object_with_reference(commit, "commit", &size, NULL);
 334
 335         if (!buf)
 336                 return -1;
 337
 338         if (!name) {
 339                 static char commit_name[60];
 340                 strcpy(commit_name, sha1_to_hex(commit));
 341                 name = commit_name;
 342         }
 343
 344         /* Root commit? */
 345         if (show_root_diff && memcmp(buf + 46, "parent ", 7)) {
 346                 header = generate_header(name, "root", buf, size);
 347                 diff_root_tree(commit, "");
 348         }
 349
 350         /* More than one parent? */
 351         if (ignore_merges) {
 352                 if (!memcmp(buf + 46 + 48, "parent ", 7))
 353                         return 0;
 354         }
 355
 356         offset = 46;
 357         while (offset + 48 < size && !memcmp(buf + offset, "parent ", 7)) {
 358                 unsigned char parent[20];
 359                 if (get_sha1_hex(buf + offset + 7, parent))
 360                         return -1;
 361                 header = generate_header(name, sha1_to_hex(parent), buf, size);
 362                 diff_tree_sha1_top(parent, commit, "");
 363                 if (!header && verbose_header) {
 364                         header_prefix = "\ndiff-tree ";
 365                         /*
 366                          * Don't print multiple merge entries if we
 367                          * don't print the diffs.
 368                          */
 369                 }
 370                 offset += 48;
 371         }
 372         return 0;
 373 }
 374
 375 static int diff_tree_stdin(char *line)
 376 {
 377         int len = strlen(line);
 378         unsigned char commit[20], parent[20];
 379         static char this_header[1000];
 380
 381         if (!len || line[len-1] != '\n')
 382                 return -1;
 383         line[len-1] = 0;
 384         if (get_sha1_hex(line, commit))
 385                 return -1;
 386         if (isspace(line[40]) && !get_sha1_hex(line+41, parent)) {
 387                 line[40] = 0;
 388                 line[81] = 0;
 389                 sprintf(this_header, "%s (from %s)\n", line, line+41);
 390                 header = this_header;
 391                 return diff_tree_sha1_top(parent, commit, "");
 392         }
 393         line[40] = 0;
 394         return diff_tree_commit(commit, line);
 395 }
 396
 397 static char *diff_tree_usage =
 398 "git-diff-tree [-p] [-r] [-z] [--stdin] [-m] [-s] [-v] [--pretty] [-t] [-R] [-B] [-M] [-C] [--find-copies-header] [-O<orderfile>] [-S<string>] [--pickaxe-all] <tree-ish> <tree-ish>";
 399
 400 int main(int argc, const char **argv)
 401 {
 402         int nr_sha1;
 403         char line[1000];
 404         unsigned char sha1[2][20];
 405
 406         nr_sha1 = 0;
 407         for (;;) {
 408                 const char *arg;
 409
 410                 argv++;
 411                 argc--;
 412                 arg = *argv;
 413                 if (!arg)
 414                         break;
 415
 416                 if (*arg != '-') {
 417                         if (nr_sha1 < 2 && !get_sha1(arg, sha1[nr_sha1])) {
 418                                 nr_sha1++;
 419                                 continue;
 420                         }
 421                         break;
 422                 }
 423
 424                 if (!strcmp(arg, "--")) {
 425                         argv++;
 426                         argc--;
 427                         break;
 428                 }
 429                 if (!strcmp(arg, "-r")) {
 430                         recursive = 1;
 431                         continue;
 432                 }
 433                 if (!strcmp(arg, "-t")) {
 434                         recursive = show_tree_entry_in_recursive = 1;
 435                         continue;
 436                 }
 437                 if (!strcmp(arg, "-R")) {
 438                         diff_setup_opt |= DIFF_SETUP_REVERSE;
 439                         continue;
 440                 }
 441                 if (!strcmp(arg, "-p")) {
 442                         diff_output_format = DIFF_FORMAT_PATCH;
 443                         recursive = 1;
 444                         continue;
 445                 }
 446                 if (!strncmp(arg, "-S", 2)) {
 447                         pickaxe = arg + 2;
 448                         continue;
 449                 }
 450                 if (!strncmp(arg, "-O", 2)) {
 451                         orderfile = arg + 2;
 452                         continue;
 453                 }
 454                 if (!strncmp(arg, "--diff-filter=", 14)) {
 455                         diff_filter = arg + 14;
 456                         continue;
 457                 }
 458                 if (!strcmp(arg, "--pickaxe-all")) {
 459                         pickaxe_opts = DIFF_PICKAXE_ALL;
 460                         continue;
 461                 }
 462                 if (!strncmp(arg, "-M", 2)) {
 463                         detect_rename = DIFF_DETECT_RENAME;
 464                         if ((diff_score_opt = diff_scoreopt_parse(arg)) == -1)
 465                                 usage(diff_tree_usage);
 466                         continue;
 467                 }
 468                 if (!strncmp(arg, "-C", 2)) {
 469                         detect_rename = DIFF_DETECT_COPY;
 470                         if ((diff_score_opt = diff_scoreopt_parse(arg)) == -1)
 471                                 usage(diff_tree_usage);
 472                         continue;
 473                 }
 474                 if (!strncmp(arg, "-B", 2)) {
 475                         if ((diff_break_opt = diff_scoreopt_parse(arg)) == -1)
 476                                 usage(diff_tree_usage);
 477                         continue;
 478                 }
 479                 if (!strcmp(arg, "--find-copies-harder")) {
 480                         find_copies_harder = 1;
 481                         continue;
 482                 }
 483                 if (!strcmp(arg, "-z")) {
 484                         diff_output_format = DIFF_FORMAT_MACHINE;
 485                         continue;
 486                 }
 487                 if (!strcmp(arg, "-m")) {
 488                         ignore_merges = 0;
 489                         continue;
 490                 }
 491                 if (!strcmp(arg, "-s")) {
 492                         diff_output_format = DIFF_FORMAT_NO_OUTPUT;
 493                         continue;
 494                 }
 495                 if (!strcmp(arg, "-v")) {
 496                         verbose_header = 1;
 497                         header_prefix = "diff-tree ";
 498                         continue;
 499                 }
 500                 if (!strncmp(arg, "--pretty", 8)) {
 501                         verbose_header = 1;
 502                         header_prefix = "diff-tree ";
 503                         commit_format = get_commit_format(arg+8);
 504                         continue;
 505                 }
 506                 if (!strcmp(arg, "--stdin")) {
 507                         read_stdin = 1;
 508                         continue;
 509                 }
 510                 if (!strcmp(arg, "--root")) {
 511                         show_root_diff = 1;
 512                         continue;
 513                 }
 514                 usage(diff_tree_usage);
 515         }
 516         if (find_copies_harder && detect_rename != DIFF_DETECT_COPY)
 517                 usage(diff_tree_usage);
 518
 519         if (argc > 0) {
 520                 int i;
 521
 522                 paths = argv;
 523                 nr_paths = argc;
 524                 pathlens = xmalloc(nr_paths * sizeof(int));
 525                 for (i=0; i<nr_paths; i++)
 526                         pathlens[i] = strlen(paths[i]);
 527         }
 528
 529         switch (nr_sha1) {
 530         case 0:
 531                 if (!read_stdin)
 532                         usage(diff_tree_usage);
 533                 break;
 534         case 1:
 535                 diff_tree_commit(sha1[0], NULL);
 536                 break;
 537         case 2:
 538                 diff_tree_sha1_top(sha1[0], sha1[1], "");
 539                 break;
 540         }
 541
 542         if (!read_stdin)
 543                 return 0;
 544
 545         if (detect_rename)
 546                 diff_setup_opt |= (DIFF_SETUP_USE_SIZE_CACHE |
 547                                    DIFF_SETUP_USE_CACHE);
 548         while (fgets(line, sizeof(line), stdin))
 549                 diff_tree_stdin(line);
 550
 551         return 0;
 552 }