Andrew's git / gitweb.git / diff-tree.c
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diff-tree.con commit Merge branch 'fixes' (82ed2bc)
   1#include <ctype.h>
   2#include "cache.h"
   3#include "diff.h"
   4#include "commit.h"
   5
   6static int show_root_diff = 0;
   7static int verbose_header = 0;
   8static int ignore_merges = 1;
   9static int recursive = 0;
  10static int show_tree_entry_in_recursive = 0;
  11static int read_stdin = 0;
  12
  13static struct diff_options diff_options;
  14
  15static const char *header = NULL;
  16static const char *header_prefix = "";
  17static enum cmit_fmt commit_format = CMIT_FMT_RAW;
  18
  19// What paths are we interested in?
  20static int nr_paths = 0;
  21static const char **paths = NULL;
  22static int *pathlens = NULL;
  23
  24static int diff_tree_sha1(const unsigned char *old, const unsigned char *new, const char *base);
  25
  26static void update_tree_entry(void **bufp, unsigned long *sizep)
  27{
  28        void *buf = *bufp;
  29        unsigned long size = *sizep;
  30        int len = strlen(buf) + 1 + 20;
  31
  32        if (size < len)
  33                die("corrupt tree file");
  34        *bufp = buf + len;
  35        *sizep = size - len;
  36}
  37
  38static const unsigned char *extract(void *tree, unsigned long size, const char **pathp, unsigned int *modep)
  39{
  40        int len = strlen(tree)+1;
  41        const unsigned char *sha1 = tree + len;
  42        const char *path = strchr(tree, ' ');
  43        unsigned int mode;
  44
  45        if (!path || size < len + 20 || sscanf(tree, "%o", &mode) != 1)
  46                die("corrupt tree file");
  47        *pathp = path+1;
  48        *modep = DIFF_FILE_CANON_MODE(mode);
  49        return sha1;
  50}
  51
  52static char *malloc_base(const char *base, const char *path, int pathlen)
  53{
  54        int baselen = strlen(base);
  55        char *newbase = xmalloc(baselen + pathlen + 2);
  56        memcpy(newbase, base, baselen);
  57        memcpy(newbase + baselen, path, pathlen);
  58        memcpy(newbase + baselen + pathlen, "/", 2);
  59        return newbase;
  60}
  61
  62static void show_file(const char *prefix, void *tree, unsigned long size, const char *base);
  63static void show_tree(const char *prefix, void *tree, unsigned long size, const char *base);
  64
  65/* A file entry went away or appeared */
  66static void show_file(const char *prefix, void *tree, unsigned long size, const char *base)
  67{
  68        unsigned mode;
  69        const char *path;
  70        const unsigned char *sha1 = extract(tree, size, &path, &mode);
  71
  72        if (recursive && S_ISDIR(mode)) {
  73                char type[20];
  74                unsigned long size;
  75                char *newbase = malloc_base(base, path, strlen(path));
  76                void *tree;
  77
  78                tree = read_sha1_file(sha1, type, &size);
  79                if (!tree || strcmp(type, "tree"))
  80                        die("corrupt tree sha %s", sha1_to_hex(sha1));
  81
  82                show_tree(prefix, tree, size, newbase);
  83
  84                free(tree);
  85                free(newbase);
  86                return;
  87        }
  88
  89        diff_addremove(&diff_options, prefix[0], mode, sha1, base, path);
  90}
  91
  92static int compare_tree_entry(void *tree1, unsigned long size1, void *tree2, unsigned long size2, const char *base)
  93{
  94        unsigned mode1, mode2;
  95        const char *path1, *path2;
  96        const unsigned char *sha1, *sha2;
  97        int cmp, pathlen1, pathlen2;
  98
  99        sha1 = extract(tree1, size1, &path1, &mode1);
 100        sha2 = extract(tree2, size2, &path2, &mode2);
 101
 102        pathlen1 = strlen(path1);
 103        pathlen2 = strlen(path2);
 104        cmp = base_name_compare(path1, pathlen1, mode1, path2, pathlen2, mode2);
 105        if (cmp < 0) {
 106                show_file("-", tree1, size1, base);
 107                return -1;
 108        }
 109        if (cmp > 0) {
 110                show_file("+", tree2, size2, base);
 111                return 1;
 112        }
 113        if (!diff_options.find_copies_harder &&
 114            !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(&diff_options, mode1, mode2,
 132                                    sha1, sha2, base, path1);
 133                retval = diff_tree_sha1(sha1, sha2, newbase);
 134                free(newbase);
 135                return retval;
 136        }
 137
 138        diff_change(&diff_options, mode1, mode2, sha1, sha2, base, path1);
 139        return 0;
 140}
 141
 142static 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 */
 196static 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
 205static 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
 242static 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
 260static void call_diff_setup_done(void)
 261{
 262        diff_setup_done(&diff_options);
 263}
 264
 265static int call_diff_flush(void)
 266{
 267        diffcore_std(&diff_options);
 268        if (diff_queue_is_empty()) {
 269                int saved_fmt = diff_options.output_format;
 270                diff_options.output_format = DIFF_FORMAT_NO_OUTPUT;
 271                diff_flush(&diff_options);
 272                diff_options.output_format = saved_fmt;
 273                return 0;
 274        }
 275        if (header) {
 276                printf("%s%c", header, diff_options.line_termination);
 277                header = NULL;
 278        }
 279        diff_flush(&diff_options);
 280        return 1;
 281}
 282
 283static int diff_tree_sha1_top(const unsigned char *old,
 284                              const unsigned char *new, const char *base)
 285{
 286        int ret;
 287
 288        call_diff_setup_done();
 289        ret = diff_tree_sha1(old, new, base);
 290        call_diff_flush();
 291        return ret;
 292}
 293
 294static int diff_root_tree(const unsigned char *new, const char *base)
 295{
 296        int retval;
 297        void *tree;
 298        unsigned long size;
 299
 300        call_diff_setup_done();
 301        tree = read_object_with_reference(new, "tree", &size, NULL);
 302        if (!tree)
 303                die("unable to read root tree (%s)", sha1_to_hex(new));
 304        retval = diff_tree("", 0, tree, size, base);
 305        free(tree);
 306        call_diff_flush();
 307        return retval;
 308}
 309
 310static const char *generate_header(const char *commit, const char *parent, const char *msg, unsigned long len)
 311{
 312        static char this_header[16384];
 313        int offset;
 314
 315        if (!verbose_header)
 316                return commit;
 317
 318        offset = sprintf(this_header, "%s%s (from %s)\n", header_prefix, commit, parent);
 319        offset += pretty_print_commit(commit_format, msg, len, this_header + offset, sizeof(this_header) - offset);
 320        return this_header;
 321}
 322
 323static int diff_tree_commit(const unsigned char *commit, const char *name)
 324{
 325        unsigned long size, offset;
 326        char *buf = read_object_with_reference(commit, "commit", &size, NULL);
 327
 328        if (!buf)
 329                return -1;
 330
 331        if (!name) {
 332                static char commit_name[60];
 333                strcpy(commit_name, sha1_to_hex(commit));
 334                name = commit_name;
 335        }
 336
 337        /* Root commit? */
 338        if (show_root_diff && memcmp(buf + 46, "parent ", 7)) {
 339                header = generate_header(name, "root", buf, size);
 340                diff_root_tree(commit, "");
 341        }
 342
 343        /* More than one parent? */
 344        if (ignore_merges) {
 345                if (!memcmp(buf + 46 + 48, "parent ", 7))
 346                        return 0;
 347        }
 348
 349        offset = 46;
 350        while (offset + 48 < size && !memcmp(buf + offset, "parent ", 7)) {
 351                unsigned char parent[20];
 352                if (get_sha1_hex(buf + offset + 7, parent))
 353                        return -1;
 354                header = generate_header(name, sha1_to_hex(parent), buf, size);
 355                diff_tree_sha1_top(parent, commit, "");
 356                if (!header && verbose_header) {
 357                        header_prefix = "\ndiff-tree ";
 358                        /*
 359                         * Don't print multiple merge entries if we
 360                         * don't print the diffs.
 361                         */
 362                }
 363                offset += 48;
 364        }
 365        free(buf);
 366        return 0;
 367}
 368
 369static int diff_tree_stdin(char *line)
 370{
 371        int len = strlen(line);
 372        unsigned char commit[20], parent[20];
 373        static char this_header[1000];
 374
 375        if (!len || line[len-1] != '\n')
 376                return -1;
 377        line[len-1] = 0;
 378        if (get_sha1_hex(line, commit))
 379                return -1;
 380        if (isspace(line[40]) && !get_sha1_hex(line+41, parent)) {
 381                line[40] = 0;
 382                line[81] = 0;
 383                sprintf(this_header, "%s (from %s)\n", line, line+41);
 384                header = this_header;
 385                return diff_tree_sha1_top(parent, commit, "");
 386        }
 387        line[40] = 0;
 388        return diff_tree_commit(commit, line);
 389}
 390
 391static int count_paths(const char **paths)
 392{
 393        int i = 0;
 394        while (*paths++)
 395                i++;
 396        return i;
 397}
 398
 399static const char diff_tree_usage[] =
 400"git-diff-tree [--stdin] [-m] [-s] [-v] [--pretty] [-t] "
 401"[<common diff options>] <tree-ish> <tree-ish>"
 402COMMON_DIFF_OPTIONS_HELP;
 403
 404int main(int argc, const char **argv)
 405{
 406        int nr_sha1;
 407        char line[1000];
 408        unsigned char sha1[2][20];
 409        const char *prefix = setup_git_directory();
 410
 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}