diff-tree.c

   1 #include <ctype.h>
   2 #include "cache.h"
   3 #include "diff.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 static int diff_output_format = DIFF_FORMAT_HUMAN;
  12 static int detect_rename = 0;
  13 static int diff_setup_opt = 0;
  14 static int diff_score_opt = 0;
  15 static const char *pickaxe = NULL;
  16 static int pickaxe_opts = 0;
  17 static int diff_break_opt = -1;
  18 static const char *orderfile = NULL;
  19 static const char *header = NULL;
  20 static const char *header_prefix = "";
  21
  22 // What paths are we interested in?
  23 static int nr_paths = 0;
  24 static const char **paths = NULL;
  25 static int *pathlens = NULL;
  26
  27 static int diff_tree_sha1(const unsigned char *old, const unsigned char *new, const char *base);
  28
  29 static void update_tree_entry(void **bufp, unsigned long *sizep)
  30 {
  31         void *buf = *bufp;
  32         unsigned long size = *sizep;
  33         int len = strlen(buf) + 1 + 20;
  34
  35         if (size < len)
  36                 die("corrupt tree file");
  37         *bufp = buf + len;
  38         *sizep = size - len;
  39 }
  40
  41 static const unsigned char *extract(void *tree, unsigned long size, const char **pathp, unsigned int *modep)
  42 {
  43         int len = strlen(tree)+1;
  44         const unsigned char *sha1 = tree + len;
  45         const char *path = strchr(tree, ' ');
  46
  47         if (!path || size < len + 20 || sscanf(tree, "%o", modep) != 1)
  48                 die("corrupt tree file");
  49         *pathp = path+1;
  50         return sha1;
  51 }
  52
  53 static char *malloc_base(const char *base, const char *path, int pathlen)
  54 {
  55         int baselen = strlen(base);
  56         char *newbase = xmalloc(baselen + pathlen + 2);
  57         memcpy(newbase, base, baselen);
  58         memcpy(newbase + baselen, path, pathlen);
  59         memcpy(newbase + baselen + pathlen, "/", 2);
  60         return newbase;
  61 }
  62
  63 static void show_file(const char *prefix, void *tree, unsigned long size, const char *base);
  64 static void show_tree(const char *prefix, void *tree, unsigned long size, const char *base);
  65
  66 /* A file entry went away or appeared */
  67 static void show_file(const char *prefix, void *tree, unsigned long size, const char *base)
  68 {
  69         unsigned mode;
  70         const char *path;
  71         const unsigned char *sha1 = extract(tree, size, &path, &mode);
  72
  73         if (recursive && S_ISDIR(mode)) {
  74                 char type[20];
  75                 unsigned long size;
  76                 char *newbase = malloc_base(base, path, strlen(path));
  77                 void *tree;
  78
  79                 tree = read_sha1_file(sha1, type, &size);
  80                 if (!tree || strcmp(type, "tree"))
  81                         die("corrupt tree sha %s", sha1_to_hex(sha1));
  82
  83                 show_tree(prefix, tree, size, newbase);
  84
  85                 free(tree);
  86                 free(newbase);
  87                 return;
  88         }
  89
  90         diff_addremove(prefix[0], mode, sha1, base, path);
  91 }
  92
  93 static int compare_tree_entry(void *tree1, unsigned long size1, void *tree2, unsigned long size2, const char *base)
  94 {
  95         unsigned mode1, mode2;
  96         const char *path1, *path2;
  97         const unsigned char *sha1, *sha2;
  98         int cmp, pathlen1, pathlen2;
  99
 100         sha1 = extract(tree1, size1, &path1, &mode1);
 101         sha2 = extract(tree2, size2, &path2, &mode2);
 102
 103         pathlen1 = strlen(path1);
 104         pathlen2 = strlen(path2);
 105         cmp = base_name_compare(path1, pathlen1, mode1, path2, pathlen2, mode2);
 106         if (cmp < 0) {
 107                 show_file("-", tree1, size1, base);
 108                 return -1;
 109         }
 110         if (cmp > 0) {
 111                 show_file("+", tree2, size2, base);
 112                 return 1;
 113         }
 114         if (!memcmp(sha1, sha2, 20) && mode1 == mode2)
 115                 return 0;
 116
 117         /*
 118          * If the filemode has changed to/from a directory from/to a regular
 119          * file, we need to consider it a remove and an add.
 120          */
 121         if (S_ISDIR(mode1) != S_ISDIR(mode2)) {
 122                 show_file("-", tree1, size1, base);
 123                 show_file("+", tree2, size2, base);
 124                 return 0;
 125         }
 126
 127         if (recursive && S_ISDIR(mode1)) {
 128                 int retval;
 129                 char *newbase = malloc_base(base, path1, pathlen1);
 130                 if (show_tree_entry_in_recursive)
 131                         diff_change(mode1, mode2, sha1, sha2, base, path1);
 132                 retval = diff_tree_sha1(sha1, sha2, newbase);
 133                 free(newbase);
 134                 return retval;
 135         }
 136
 137         diff_change(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(void)
 260 {
 261         diff_setup(diff_setup_opt);
 262 }
 263
 264 static int call_diff_flush(void)
 265 {
 266         diffcore_std(0,
 267                      detect_rename, diff_score_opt,
 268                      pickaxe, pickaxe_opts,
 269                      diff_break_opt,
 270                      orderfile);
 271         if (diff_queue_is_empty()) {
 272                 diff_flush(DIFF_FORMAT_NO_OUTPUT, 0);
 273                 return 0;
 274         }
 275         if (header) {
 276                 const char *fmt = "%s";
 277                 if (diff_output_format == DIFF_FORMAT_MACHINE)
 278                         fmt = "%s%c";
 279
 280                 printf(fmt, header, 0);
 281                 header = NULL;
 282         }
 283         diff_flush(diff_output_format, 1);
 284         return 1;
 285 }
 286
 287 static int diff_tree_sha1_top(const unsigned char *old,
 288                               const unsigned char *new, const char *base)
 289 {
 290         int ret;
 291
 292         call_diff_setup();
 293         ret = diff_tree_sha1(old, new, base);
 294         call_diff_flush();
 295         return ret;
 296 }
 297
 298 static int diff_root_tree(const unsigned char *new, const char *base)
 299 {
 300         int retval;
 301         void *tree;
 302         unsigned long size;
 303
 304         call_diff_setup();
 305         tree = read_object_with_reference(new, "tree", &size, NULL);
 306         if (!tree)
 307                 die("unable to read root tree (%s)", sha1_to_hex(new));
 308         retval = diff_tree("", 0, tree, size, base);
 309         free(tree);
 310         call_diff_flush();
 311         return retval;
 312 }
 313
 314 static int get_one_line(const char *msg, unsigned long len)
 315 {
 316         int ret = 0;
 317
 318         while (len--) {
 319                 ret++;
 320                 if (*msg++ == '\n')
 321                         break;
 322         }
 323         return ret;
 324 }
 325
 326 static int add_author_info(char *buf, const char *line, int len)
 327 {
 328         char *date;
 329         unsigned int namelen;
 330         unsigned long time;
 331         int tz;
 332
 333         line += strlen("author ");
 334         date = strchr(line, '>');
 335         if (!date)
 336                 return 0;
 337         namelen = ++date - line;
 338         time = strtoul(date, &date, 10);
 339         tz = strtol(date, NULL, 10);
 340
 341         return sprintf(buf, "Author: %.*s\nDate:   %s\n",
 342                 namelen, line,
 343                 show_date(time, tz));
 344 }
 345
 346 static char *generate_header(const char *commit, const char *parent, const char *msg, unsigned long len)
 347 {
 348         static char this_header[16384];
 349         int offset;
 350
 351         offset = sprintf(this_header, "%s%s (from %s)\n", header_prefix, commit, parent);
 352         if (verbose_header) {
 353                 int hdr = 1;
 354
 355                 for (;;) {
 356                         const char *line = msg;
 357                         int linelen = get_one_line(msg, len);
 358
 359                         if (!linelen)
 360                                 break;
 361
 362                         /*
 363                          * We want some slop for indentation and a possible
 364                          * final "...". Thus the "+ 20".
 365                          */
 366                         if (offset + linelen + 20 > sizeof(this_header)) {
 367                                 memcpy(this_header + offset, "    ...\n", 8);
 368                                 offset += 8;
 369                                 break;
 370                         }
 371
 372                         msg += linelen;
 373                         len -= linelen;
 374                         if (linelen == 1)
 375                                 hdr = 0;
 376                         if (hdr) {
 377                                 if (!memcmp(line, "author ", 7))
 378                                         offset += add_author_info(this_header + offset, line, linelen);
 379                                 continue;
 380                         }
 381                         memset(this_header + offset, ' ', 4);
 382                         memcpy(this_header + offset + 4, line, linelen);
 383                         offset += linelen + 4;
 384                 }
 385                 /* Make sure there is an EOLN */
 386                 if (this_header[offset-1] != '\n')
 387                         this_header[offset++] = '\n';
 388                 /* Add _another_ EOLN if we are doing diff output */
 389                 this_header[offset++] = '\n';
 390                 this_header[offset] = 0;
 391         }
 392
 393         return this_header;
 394 }
 395
 396 static int diff_tree_commit(const unsigned char *commit, const char *name)
 397 {
 398         unsigned long size, offset;
 399         char *buf = read_object_with_reference(commit, "commit", &size, NULL);
 400
 401         if (!buf)
 402                 return -1;
 403
 404         if (!name) {
 405                 static char commit_name[60];
 406                 strcpy(commit_name, sha1_to_hex(commit));
 407                 name = commit_name;
 408         }
 409
 410         /* Root commit? */
 411         if (show_root_diff && memcmp(buf + 46, "parent ", 7)) {
 412                 header = generate_header(name, "root", buf, size);
 413                 diff_root_tree(commit, "");
 414         }
 415
 416         /* More than one parent? */
 417         if (ignore_merges) {
 418                 if (!memcmp(buf + 46 + 48, "parent ", 7))
 419                         return 0;
 420         }
 421
 422         offset = 46;
 423         while (offset + 48 < size && !memcmp(buf + offset, "parent ", 7)) {
 424                 unsigned char parent[20];
 425                 if (get_sha1_hex(buf + offset + 7, parent))
 426                         return -1;
 427                 header = generate_header(name, sha1_to_hex(parent), buf, size);
 428                 diff_tree_sha1_top(parent, commit, "");
 429                 if (!header && verbose_header) {
 430                         header_prefix = "\ndiff-tree ";
 431                         /*
 432                          * Don't print multiple merge entries if we
 433                          * don't print the diffs.
 434                          */
 435                 }
 436                 offset += 48;
 437         }
 438         return 0;
 439 }
 440
 441 static int diff_tree_stdin(char *line)
 442 {
 443         int len = strlen(line);
 444         unsigned char commit[20], parent[20];
 445         static char this_header[1000];
 446
 447         if (!len || line[len-1] != '\n')
 448                 return -1;
 449         line[len-1] = 0;
 450         if (get_sha1_hex(line, commit))
 451                 return -1;
 452         if (isspace(line[40]) && !get_sha1_hex(line+41, parent)) {
 453                 line[40] = 0;
 454                 line[81] = 0;
 455                 sprintf(this_header, "%s (from %s)\n", line, line+41);
 456                 header = this_header;
 457                 return diff_tree_sha1_top(parent, commit, "");
 458         }
 459         line[40] = 0;
 460         return diff_tree_commit(commit, line);
 461 }
 462
 463 static char *diff_tree_usage =
 464 "git-diff-tree [-p] [-r] [-z] [--stdin] [-M] [-C] [-R] [-S<string>] [-m] [-s] [-v] [-t] <tree-ish> <tree-ish>";
 465
 466 int main(int argc, const char **argv)
 467 {
 468         int nr_sha1;
 469         char line[1000];
 470         unsigned char sha1[2][20];
 471
 472         nr_sha1 = 0;
 473         for (;;) {
 474                 const char *arg;
 475
 476                 argv++;
 477                 argc--;
 478                 arg = *argv;
 479                 if (!arg)
 480                         break;
 481
 482                 if (*arg != '-') {
 483                         if (nr_sha1 < 2 && !get_sha1(arg, sha1[nr_sha1])) {
 484                                 nr_sha1++;
 485                                 continue;
 486                         }
 487                         break;
 488                 }
 489
 490                 if (!strcmp(arg, "--")) {
 491                         argv++;
 492                         argc--;
 493                         break;
 494                 }
 495                 if (!strcmp(arg, "-r")) {
 496                         recursive = 1;
 497                         continue;
 498                 }
 499                 if (!strcmp(arg, "-t")) {
 500                         recursive = show_tree_entry_in_recursive = 1;
 501                         continue;
 502                 }
 503                 if (!strcmp(arg, "-R")) {
 504                         diff_setup_opt |= DIFF_SETUP_REVERSE;
 505                         continue;
 506                 }
 507                 if (!strcmp(arg, "-p")) {
 508                         diff_output_format = DIFF_FORMAT_PATCH;
 509                         recursive = 1;
 510                         continue;
 511                 }
 512                 if (!strncmp(arg, "-S", 2)) {
 513                         pickaxe = arg + 2;
 514                         continue;
 515                 }
 516                 if (!strncmp(arg, "-O", 2)) {
 517                         orderfile = arg + 2;
 518                         continue;
 519                 }
 520                 if (!strcmp(arg, "--pickaxe-all")) {
 521                         pickaxe_opts = DIFF_PICKAXE_ALL;
 522                         continue;
 523                 }
 524                 if (!strncmp(arg, "-M", 2)) {
 525                         detect_rename = DIFF_DETECT_RENAME;
 526                         diff_score_opt = diff_scoreopt_parse(arg);
 527                         continue;
 528                 }
 529                 if (!strncmp(arg, "-C", 2)) {
 530                         detect_rename = DIFF_DETECT_COPY;
 531                         diff_score_opt = diff_scoreopt_parse(arg);
 532                         continue;
 533                 }
 534                 if (!strncmp(arg, "-B", 2)) {
 535                         diff_break_opt = diff_scoreopt_parse(arg);
 536                         continue;
 537                 }
 538                 if (!strcmp(arg, "-z")) {
 539                         diff_output_format = DIFF_FORMAT_MACHINE;
 540                         continue;
 541                 }
 542                 if (!strcmp(arg, "-m")) {
 543                         ignore_merges = 0;
 544                         continue;
 545                 }
 546                 if (!strcmp(arg, "-s")) {
 547                         diff_output_format = DIFF_FORMAT_NO_OUTPUT;
 548                         continue;
 549                 }
 550                 if (!strcmp(arg, "-v")) {
 551                         verbose_header = 1;
 552                         header_prefix = "diff-tree ";
 553                         continue;
 554                 }
 555                 if (!strcmp(arg, "--stdin")) {
 556                         read_stdin = 1;
 557                         continue;
 558                 }
 559                 if (!strcmp(arg, "--root")) {
 560                         show_root_diff = 1;
 561                         continue;
 562                 }
 563                 usage(diff_tree_usage);
 564         }
 565
 566         if (argc > 0) {
 567                 int i;
 568
 569                 paths = argv;
 570                 nr_paths = argc;
 571                 pathlens = xmalloc(nr_paths * sizeof(int));
 572                 for (i=0; i<nr_paths; i++)
 573                         pathlens[i] = strlen(paths[i]);
 574         }
 575
 576         switch (nr_sha1) {
 577         case 0:
 578                 if (!read_stdin)
 579                         usage(diff_tree_usage);
 580                 break;
 581         case 1:
 582                 diff_tree_commit(sha1[0], NULL);
 583                 break;
 584         case 2:
 585                 diff_tree_sha1_top(sha1[0], sha1[1], "");
 586                 break;
 587         }
 588
 589         if (!read_stdin)
 590                 return 0;
 591
 592         if (detect_rename)
 593                 diff_setup_opt |= (DIFF_SETUP_USE_SIZE_CACHE |
 594                                    DIFF_SETUP_USE_CACHE);
 595         while (fgets(line, sizeof(line), stdin))
 596                 diff_tree_stdin(line);
 597
 598         return 0;
 599 }