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
  48         if (!path || size < len + 20 || sscanf(tree, "%o", modep) != 1)
  49                 die("corrupt tree file");
  50         *pathp = path+1;
  51         return sha1;
  52 }
  53
  54 static char *malloc_base(const char *base, const char *path, int pathlen)
  55 {
  56         int baselen = strlen(base);
  57         char *newbase = xmalloc(baselen + pathlen + 2);
  58         memcpy(newbase, base, baselen);
  59         memcpy(newbase + baselen, path, pathlen);
  60         memcpy(newbase + baselen + pathlen, "/", 2);
  61         return newbase;
  62 }
  63
  64 static void show_file(const char *prefix, void *tree, unsigned long size, const char *base);
  65 static void show_tree(const char *prefix, void *tree, unsigned long size, const char *base);
  66
  67 /* A file entry went away or appeared */
  68 static void show_file(const char *prefix, void *tree, unsigned long size, const char *base)
  69 {
  70         unsigned mode;
  71         const char *path;
  72         const unsigned char *sha1 = extract(tree, size, &path, &mode);
  73
  74         if (recursive && S_ISDIR(mode)) {
  75                 char type[20];
  76                 unsigned long size;
  77                 char *newbase = malloc_base(base, path, strlen(path));
  78                 void *tree;
  79
  80                 tree = read_sha1_file(sha1, type, &size);
  81                 if (!tree || strcmp(type, "tree"))
  82                         die("corrupt tree sha %s", sha1_to_hex(sha1));
  83
  84                 show_tree(prefix, tree, size, newbase);
  85
  86                 free(tree);
  87                 free(newbase);
  88                 return;
  89         }
  90
  91         diff_addremove(prefix[0], mode, sha1, base, path);
  92 }
  93
  94 static int compare_tree_entry(void *tree1, unsigned long size1, void *tree2, unsigned long size2, const char *base)
  95 {
  96         unsigned mode1, mode2;
  97         const char *path1, *path2;
  98         const unsigned char *sha1, *sha2;
  99         int cmp, pathlen1, pathlen2;
 100
 101         sha1 = extract(tree1, size1, &path1, &mode1);
 102         sha2 = extract(tree2, size2, &path2, &mode2);
 103
 104         pathlen1 = strlen(path1);
 105         pathlen2 = strlen(path2);
 106         cmp = base_name_compare(path1, pathlen1, mode1, path2, pathlen2, mode2);
 107         if (cmp < 0) {
 108                 show_file("-", tree1, size1, base);
 109                 return -1;
 110         }
 111         if (cmp > 0) {
 112                 show_file("+", tree2, size2, base);
 113                 return 1;
 114         }
 115         if (!memcmp(sha1, sha2, 20) && mode1 == mode2)
 116                 return 0;
 117
 118         /*
 119          * If the filemode has changed to/from a directory from/to a regular
 120          * file, we need to consider it a remove and an add.
 121          */
 122         if (S_ISDIR(mode1) != S_ISDIR(mode2)) {
 123                 show_file("-", tree1, size1, base);
 124                 show_file("+", tree2, size2, base);
 125                 return 0;
 126         }
 127
 128         if (recursive && S_ISDIR(mode1)) {
 129                 int retval;
 130                 char *newbase = malloc_base(base, path1, pathlen1);
 131                 if (show_tree_entry_in_recursive)
 132                         diff_change(mode1, mode2, sha1, sha2, base, path1);
 133                 retval = diff_tree_sha1(sha1, sha2, newbase);
 134                 free(newbase);
 135                 return retval;
 136         }
 137
 138         diff_change(mode1, mode2, sha1, sha2, base, path1);
 139         return 0;
 140 }
 141
 142 static int interesting(void *tree, unsigned long size, const char *base)
 143 {
 144         const char *path;
 145         unsigned mode;
 146         int i;
 147         int baselen, pathlen;
 148
 149         if (!nr_paths)
 150                 return 1;
 151
 152         (void)extract(tree, size, &path, &mode);
 153
 154         pathlen = strlen(path);
 155         baselen = strlen(base);
 156
 157         for (i=0; i < nr_paths; i++) {
 158                 const char *match = paths[i];
 159                 int matchlen = pathlens[i];
 160
 161                 if (baselen >= matchlen) {
 162                         /* If it doesn't match, move along... */
 163                         if (strncmp(base, match, matchlen))
 164                                 continue;
 165
 166                         /* The base is a subdirectory of a path which was specified. */
 167                         return 1;
 168                 }
 169
 170                 /* Does the base match? */
 171                 if (strncmp(base, match, baselen))
 172                         continue;
 173
 174                 match += baselen;
 175                 matchlen -= baselen;
 176
 177                 if (pathlen > matchlen)
 178                         continue;
 179
 180                 if (matchlen > pathlen) {
 181                         if (match[pathlen] != '/')
 182                                 continue;
 183                         if (!S_ISDIR(mode))
 184                                 continue;
 185                 }
 186
 187                 if (strncmp(path, match, pathlen))
 188                         continue;
 189
 190                 return 1;
 191         }
 192         return 0; /* No matches */
 193 }
 194
 195 /* A whole sub-tree went away or appeared */
 196 static void show_tree(const char *prefix, void *tree, unsigned long size, const char *base)
 197 {
 198         while (size) {
 199                 if (interesting(tree, size, base))
 200                         show_file(prefix, tree, size, base);
 201                 update_tree_entry(&tree, &size);
 202         }
 203 }
 204
 205 static int diff_tree(void *tree1, unsigned long size1, void *tree2, unsigned long size2, const char *base)
 206 {
 207         while (size1 | size2) {
 208                 if (nr_paths && size1 && !interesting(tree1, size1, base)) {
 209                         update_tree_entry(&tree1, &size1);
 210                         continue;
 211                 }
 212                 if (nr_paths && size2 && !interesting(tree2, size2, base)) {
 213                         update_tree_entry(&tree2, &size2);
 214                         continue;
 215                 }
 216                 if (!size1) {
 217                         show_file("+", tree2, size2, base);
 218                         update_tree_entry(&tree2, &size2);
 219                         continue;
 220                 }
 221                 if (!size2) {
 222                         show_file("-", tree1, size1, base);
 223                         update_tree_entry(&tree1, &size1);
 224                         continue;
 225                 }
 226                 switch (compare_tree_entry(tree1, size1, tree2, size2, base)) {
 227                 case -1:
 228                         update_tree_entry(&tree1, &size1);
 229                         continue;
 230                 case 0:
 231                         update_tree_entry(&tree1, &size1);
 232                         /* Fallthrough */
 233                 case 1:
 234                         update_tree_entry(&tree2, &size2);
 235                         continue;
 236                 }
 237                 die("git-diff-tree: internal error");
 238         }
 239         return 0;
 240 }
 241
 242 static int diff_tree_sha1(const unsigned char *old, const unsigned char *new, const char *base)
 243 {
 244         void *tree1, *tree2;
 245         unsigned long size1, size2;
 246         int retval;
 247
 248         tree1 = read_object_with_reference(old, "tree", &size1, NULL);
 249         if (!tree1)
 250                 die("unable to read source tree (%s)", sha1_to_hex(old));
 251         tree2 = read_object_with_reference(new, "tree", &size2, NULL);
 252         if (!tree2)
 253                 die("unable to read destination tree (%s)", sha1_to_hex(new));
 254         retval = diff_tree(tree1, size1, tree2, size2, base);
 255         free(tree1);
 256         free(tree2);
 257         return retval;
 258 }
 259
 260 static void call_diff_setup(void)
 261 {
 262         diff_setup(diff_setup_opt);
 263 }
 264
 265 static int call_diff_flush(void)
 266 {
 267         diffcore_std(0,
 268                      detect_rename, diff_score_opt,
 269                      pickaxe, pickaxe_opts,
 270                      diff_break_opt,
 271                      orderfile);
 272         if (diff_queue_is_empty()) {
 273                 diff_flush(DIFF_FORMAT_NO_OUTPUT, 0);
 274                 return 0;
 275         }
 276         if (header) {
 277                 const char *fmt = "%s";
 278                 if (diff_output_format == DIFF_FORMAT_MACHINE)
 279                         fmt = "%s%c";
 280
 281                 printf(fmt, header, 0);
 282                 header = NULL;
 283         }
 284         diff_flush(diff_output_format, 1);
 285         return 1;
 286 }
 287
 288 static int diff_tree_sha1_top(const unsigned char *old,
 289                               const unsigned char *new, const char *base)
 290 {
 291         int ret;
 292
 293         call_diff_setup();
 294         ret = diff_tree_sha1(old, new, base);
 295         call_diff_flush();
 296         return ret;
 297 }
 298
 299 static int diff_root_tree(const unsigned char *new, const char *base)
 300 {
 301         int retval;
 302         void *tree;
 303         unsigned long size;
 304
 305         call_diff_setup();
 306         tree = read_object_with_reference(new, "tree", &size, NULL);
 307         if (!tree)
 308                 die("unable to read root tree (%s)", sha1_to_hex(new));
 309         retval = diff_tree("", 0, tree, size, base);
 310         free(tree);
 311         call_diff_flush();
 312         return retval;
 313 }
 314
 315 static char *generate_header(const char *commit, const char *parent, const char *msg, unsigned long len)
 316 {
 317         static char this_header[16384];
 318         int offset;
 319
 320         offset = sprintf(this_header, "%s%s (from %s)\n", header_prefix, commit, parent);
 321         if (verbose_header) {
 322                 offset += pretty_print_commit(msg, len, this_header + offset, sizeof(this_header) - offset);
 323                 this_header[offset++] = '\n';
 324                 this_header[offset++] = 0;
 325         }
 326
 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] [-C] [-R] [-S<string>] [-m] [-s] [-v] [-t] <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 (!strcmp(arg, "--pickaxe-all")) {
 455                         pickaxe_opts = DIFF_PICKAXE_ALL;
 456                         continue;
 457                 }
 458                 if (!strncmp(arg, "-M", 2)) {
 459                         detect_rename = DIFF_DETECT_RENAME;
 460                         diff_score_opt = diff_scoreopt_parse(arg);
 461                         continue;
 462                 }
 463                 if (!strncmp(arg, "-C", 2)) {
 464                         detect_rename = DIFF_DETECT_COPY;
 465                         diff_score_opt = diff_scoreopt_parse(arg);
 466                         continue;
 467                 }
 468                 if (!strncmp(arg, "-B", 2)) {
 469                         diff_break_opt = diff_scoreopt_parse(arg);
 470                         continue;
 471                 }
 472                 if (!strcmp(arg, "-z")) {
 473                         diff_output_format = DIFF_FORMAT_MACHINE;
 474                         continue;
 475                 }
 476                 if (!strcmp(arg, "-m")) {
 477                         ignore_merges = 0;
 478                         continue;
 479                 }
 480                 if (!strcmp(arg, "-s")) {
 481                         diff_output_format = DIFF_FORMAT_NO_OUTPUT;
 482                         continue;
 483                 }
 484                 if (!strcmp(arg, "-v")) {
 485                         verbose_header = 1;
 486                         header_prefix = "diff-tree ";
 487                         continue;
 488                 }
 489                 if (!strcmp(arg, "--stdin")) {
 490                         read_stdin = 1;
 491                         continue;
 492                 }
 493                 if (!strcmp(arg, "--root")) {
 494                         show_root_diff = 1;
 495                         continue;
 496                 }
 497                 usage(diff_tree_usage);
 498         }
 499
 500         if (argc > 0) {
 501                 int i;
 502
 503                 paths = argv;
 504                 nr_paths = argc;
 505                 pathlens = xmalloc(nr_paths * sizeof(int));
 506                 for (i=0; i<nr_paths; i++)
 507                         pathlens[i] = strlen(paths[i]);
 508         }
 509
 510         switch (nr_sha1) {
 511         case 0:
 512                 if (!read_stdin)
 513                         usage(diff_tree_usage);
 514                 break;
 515         case 1:
 516                 diff_tree_commit(sha1[0], NULL);
 517                 break;
 518         case 2:
 519                 diff_tree_sha1_top(sha1[0], sha1[1], "");
 520                 break;
 521         }
 522
 523         if (!read_stdin)
 524                 return 0;
 525
 526         if (detect_rename)
 527                 diff_setup_opt |= (DIFF_SETUP_USE_SIZE_CACHE |
 528                                    DIFF_SETUP_USE_CACHE);
 529         while (fgets(line, sizeof(line), stdin))
 530                 diff_tree_stdin(line);
 531
 532         return 0;
 533 }