diff-tree.c

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