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