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