Andrew's git / gitweb.git / diff-tree.c
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diff-tree.con commit Add "commit" helper script (a3e870f)
   1#include <ctype.h>
   2#include "cache.h"
   3#include "diff.h"
   4
   5static int show_root_diff = 0;
   6static int verbose_header = 0;
   7static int ignore_merges = 1;
   8static int recursive = 0;
   9static int show_tree_entry_in_recursive = 0;
  10static int read_stdin = 0;
  11static int diff_output_format = DIFF_FORMAT_HUMAN;
  12static int detect_rename = 0;
  13static int diff_setup_opt = 0;
  14static int diff_score_opt = 0;
  15static const char *pickaxe = NULL;
  16static int pickaxe_opts = 0;
  17static int diff_break_opt = -1;
  18static const char *header = NULL;
  19static const char *header_prefix = "";
  20
  21// What paths are we interested in?
  22static int nr_paths = 0;
  23static const char **paths = NULL;
  24static int *pathlens = NULL;
  25
  26static int diff_tree_sha1(const unsigned char *old, const unsigned char *new, const char *base);
  27
  28static void update_tree_entry(void **bufp, unsigned long *sizep)
  29{
  30        void *buf = *bufp;
  31        unsigned long size = *sizep;
  32        int len = strlen(buf) + 1 + 20;
  33
  34        if (size < len)
  35                die("corrupt tree file");
  36        *bufp = buf + len;
  37        *sizep = size - len;
  38}
  39
  40static const unsigned char *extract(void *tree, unsigned long size, const char **pathp, unsigned int *modep)
  41{
  42        int len = strlen(tree)+1;
  43        const unsigned char *sha1 = tree + len;
  44        const char *path = strchr(tree, ' ');
  45
  46        if (!path || size < len + 20 || sscanf(tree, "%o", modep) != 1)
  47                die("corrupt tree file");
  48        *pathp = path+1;
  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(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 (!memcmp(sha1, sha2, 20) && mode1 == mode2)
 114                return 0;
 115
 116        /*
 117         * If the filemode has changed to/from a directory from/to a regular
 118         * file, we need to consider it a remove and an add.
 119         */
 120        if (S_ISDIR(mode1) != S_ISDIR(mode2)) {
 121                show_file("-", tree1, size1, base);
 122                show_file("+", tree2, size2, base);
 123                return 0;
 124        }
 125
 126        if (recursive && S_ISDIR(mode1)) {
 127                int retval;
 128                char *newbase = malloc_base(base, path1, pathlen1);
 129                if (show_tree_entry_in_recursive)
 130                        diff_change(mode1, mode2, sha1, sha2, base, path1);
 131                retval = diff_tree_sha1(sha1, sha2, newbase);
 132                free(newbase);
 133                return retval;
 134        }
 135
 136        diff_change(mode1, mode2, sha1, sha2, base, path1);
 137        return 0;
 138}
 139
 140static int interesting(void *tree, unsigned long size, const char *base)
 141{
 142        const char *path;
 143        unsigned mode;
 144        int i;
 145        int baselen, pathlen;
 146
 147        if (!nr_paths)
 148                return 1;
 149
 150        (void)extract(tree, size, &path, &mode);
 151
 152        pathlen = strlen(path);
 153        baselen = strlen(base);
 154
 155        for (i=0; i < nr_paths; i++) {
 156                const char *match = paths[i];
 157                int matchlen = pathlens[i];
 158
 159                if (baselen >= matchlen) {
 160                        /* If it doesn't match, move along... */
 161                        if (strncmp(base, match, matchlen))
 162                                continue;
 163
 164                        /* The base is a subdirectory of a path which was specified. */
 165                        return 1;
 166                }
 167
 168                /* Does the base match? */
 169                if (strncmp(base, match, baselen))
 170                        continue;
 171
 172                match += baselen;
 173                matchlen -= baselen;
 174
 175                if (pathlen > matchlen)
 176                        continue;
 177
 178                if (matchlen > pathlen) {
 179                        if (match[pathlen] != '/')
 180                                continue;
 181                        if (!S_ISDIR(mode))
 182                                continue;
 183                }
 184
 185                if (strncmp(path, match, pathlen))
 186                        continue;
 187
 188                return 1;
 189        }
 190        return 0; /* No matches */
 191}
 192
 193/* A whole sub-tree went away or appeared */
 194static void show_tree(const char *prefix, void *tree, unsigned long size, const char *base)
 195{
 196        while (size) {
 197                if (interesting(tree, size, base))
 198                        show_file(prefix, tree, size, base);
 199                update_tree_entry(&tree, &size);
 200        }
 201}
 202
 203static int diff_tree(void *tree1, unsigned long size1, void *tree2, unsigned long size2, const char *base)
 204{
 205        while (size1 | size2) {
 206                if (nr_paths && size1 && !interesting(tree1, size1, base)) {
 207                        update_tree_entry(&tree1, &size1);
 208                        continue;
 209                }
 210                if (nr_paths && size2 && !interesting(tree2, size2, base)) {
 211                        update_tree_entry(&tree2, &size2);
 212                        continue;
 213                }
 214                if (!size1) {
 215                        show_file("+", tree2, size2, base);
 216                        update_tree_entry(&tree2, &size2);
 217                        continue;
 218                }
 219                if (!size2) {
 220                        show_file("-", tree1, size1, base);
 221                        update_tree_entry(&tree1, &size1);
 222                        continue;
 223                }
 224                switch (compare_tree_entry(tree1, size1, tree2, size2, base)) {
 225                case -1:
 226                        update_tree_entry(&tree1, &size1);
 227                        continue;
 228                case 0:
 229                        update_tree_entry(&tree1, &size1);
 230                        /* Fallthrough */
 231                case 1:
 232                        update_tree_entry(&tree2, &size2);
 233                        continue;
 234                }
 235                die("git-diff-tree: internal error");
 236        }
 237        return 0;
 238}
 239
 240static int diff_tree_sha1(const unsigned char *old, const unsigned char *new, const char *base)
 241{
 242        void *tree1, *tree2;
 243        unsigned long size1, size2;
 244        int retval;
 245
 246        tree1 = read_object_with_reference(old, "tree", &size1, NULL);
 247        if (!tree1)
 248                die("unable to read source tree (%s)", sha1_to_hex(old));
 249        tree2 = read_object_with_reference(new, "tree", &size2, NULL);
 250        if (!tree2)
 251                die("unable to read destination tree (%s)", sha1_to_hex(new));
 252        retval = diff_tree(tree1, size1, tree2, size2, base);
 253        free(tree1);
 254        free(tree2);
 255        return retval;
 256}
 257
 258static void call_diff_setup(void)
 259{
 260        diff_setup(diff_setup_opt);
 261}
 262
 263static int call_diff_flush(void)
 264{
 265        diffcore_std(0,
 266                     detect_rename, diff_score_opt,
 267                     pickaxe, pickaxe_opts,
 268                     diff_break_opt);
 269        if (diff_queue_is_empty()) {
 270                diff_flush(DIFF_FORMAT_NO_OUTPUT, 0);
 271                return 0;
 272        }
 273        if (header) {
 274                const char *fmt = "%s";
 275                if (diff_output_format == DIFF_FORMAT_MACHINE)
 276                        fmt = "%s%c";
 277                
 278                printf(fmt, header, 0);
 279                header = NULL;
 280        }
 281        diff_flush(diff_output_format, 1);
 282        return 1;
 283}
 284
 285static int diff_tree_sha1_top(const unsigned char *old,
 286                              const unsigned char *new, const char *base)
 287{
 288        int ret;
 289
 290        call_diff_setup();
 291        ret = diff_tree_sha1(old, new, base);
 292        call_diff_flush();
 293        return ret;
 294}
 295
 296static int diff_root_tree(const unsigned char *new, const char *base)
 297{
 298        int retval;
 299        void *tree;
 300        unsigned long size;
 301
 302        call_diff_setup();
 303        tree = read_object_with_reference(new, "tree", &size, NULL);
 304        if (!tree)
 305                die("unable to read root tree (%s)", sha1_to_hex(new));
 306        retval = diff_tree("", 0, tree, size, base);
 307        free(tree);
 308        call_diff_flush();
 309        return retval;
 310}
 311
 312static int get_one_line(const char *msg, unsigned long len)
 313{
 314        int ret = 0;
 315
 316        while (len--) {
 317                ret++;
 318                if (*msg++ == '\n')
 319                        break;
 320        }
 321        return ret;
 322}
 323
 324static int add_author_info(char *buf, const char *line, int len)
 325{
 326        char *date;
 327        unsigned int namelen;
 328        unsigned long time;
 329        int tz;
 330
 331        line += strlen("author ");
 332        date = strchr(line, '>');
 333        if (!date)
 334                return 0;
 335        namelen = ++date - line;
 336        time = strtoul(date, &date, 10);
 337        tz = strtol(date, NULL, 10);
 338
 339        return sprintf(buf, "Author: %.*s\nDate:   %s\n",
 340                namelen, line,
 341                show_date(time, tz));
 342}
 343
 344static char *generate_header(const char *commit, const char *parent, const char *msg, unsigned long len)
 345{
 346        static char this_header[16384];
 347        int offset;
 348
 349        offset = sprintf(this_header, "%s%s (from %s)\n", header_prefix, commit, parent);
 350        if (verbose_header) {
 351                int hdr = 1;
 352
 353                for (;;) {
 354                        const char *line = msg;
 355                        int linelen = get_one_line(msg, len);
 356
 357                        if (!linelen)
 358                                break;
 359
 360                        /*
 361                         * We want some slop for indentation and a possible
 362                         * final "...". Thus the "+ 20".
 363                         */
 364                        if (offset + linelen + 20 > sizeof(this_header)) {
 365                                memcpy(this_header + offset, "    ...\n", 8);
 366                                offset += 8;
 367                                break;
 368                        }
 369
 370                        msg += linelen;
 371                        len -= linelen;
 372                        if (linelen == 1)
 373                                hdr = 0;
 374                        if (hdr) {
 375                                if (!memcmp(line, "author ", 7))
 376                                        offset += add_author_info(this_header + offset, line, linelen);
 377                                continue;
 378                        }
 379                        memset(this_header + offset, ' ', 4);
 380                        memcpy(this_header + offset + 4, line, linelen);
 381                        offset += linelen + 4;
 382                }
 383                /* Make sure there is an EOLN */
 384                if (this_header[offset-1] != '\n')
 385                        this_header[offset++] = '\n';
 386                /* Add _another_ EOLN if we are doing diff output */
 387                this_header[offset++] = '\n';
 388                this_header[offset] = 0;
 389        }
 390
 391        return this_header;
 392}
 393
 394static int diff_tree_commit(const unsigned char *commit, const char *name)
 395{
 396        unsigned long size, offset;
 397        char *buf = read_object_with_reference(commit, "commit", &size, NULL);
 398
 399        if (!buf)
 400                return -1;
 401
 402        if (!name) {
 403                static char commit_name[60];
 404                strcpy(commit_name, sha1_to_hex(commit));
 405                name = commit_name;
 406        }
 407
 408        /* Root commit? */
 409        if (show_root_diff && memcmp(buf + 46, "parent ", 7)) {
 410                header = generate_header(name, "root", buf, size);
 411                diff_root_tree(commit, "");
 412        }
 413
 414        /* More than one parent? */
 415        if (ignore_merges) {
 416                if (!memcmp(buf + 46 + 48, "parent ", 7))
 417                        return 0;
 418        }
 419
 420        offset = 46;
 421        while (offset + 48 < size && !memcmp(buf + offset, "parent ", 7)) {
 422                unsigned char parent[20];
 423                if (get_sha1_hex(buf + offset + 7, parent))
 424                        return -1;
 425                header = generate_header(name, sha1_to_hex(parent), buf, size);
 426                diff_tree_sha1_top(parent, commit, "");
 427                if (!header && verbose_header) {
 428                        header_prefix = "\ndiff-tree ";
 429                        /*
 430                         * Don't print multiple merge entries if we
 431                         * don't print the diffs.
 432                         */
 433                }
 434                offset += 48;
 435        }
 436        return 0;
 437}
 438
 439static int diff_tree_stdin(char *line)
 440{
 441        int len = strlen(line);
 442        unsigned char commit[20], parent[20];
 443        static char this_header[1000];
 444
 445        if (!len || line[len-1] != '\n')
 446                return -1;
 447        line[len-1] = 0;
 448        if (get_sha1_hex(line, commit))
 449                return -1;
 450        if (isspace(line[40]) && !get_sha1_hex(line+41, parent)) {
 451                line[40] = 0;
 452                line[81] = 0;
 453                sprintf(this_header, "%s (from %s)\n", line, line+41);
 454                header = this_header;
 455                return diff_tree_sha1_top(parent, commit, "");
 456        }
 457        line[40] = 0;
 458        return diff_tree_commit(commit, line);
 459}
 460
 461static char *diff_tree_usage =
 462"git-diff-tree [-p] [-r] [-z] [--stdin] [-M] [-C] [-R] [-S<string>] [-m] [-s] [-v] [-t] <tree-ish> <tree-ish>";
 463
 464int main(int argc, const char **argv)
 465{
 466        int nr_sha1;
 467        char line[1000];
 468        unsigned char sha1[2][20];
 469
 470        nr_sha1 = 0;
 471        for (;;) {
 472                const char *arg;
 473
 474                argv++;
 475                argc--;
 476                arg = *argv;
 477                if (!arg)
 478                        break;
 479
 480                if (*arg != '-') {
 481                        if (nr_sha1 < 2 && !get_sha1(arg, sha1[nr_sha1])) {
 482                                nr_sha1++;
 483                                continue;
 484                        }
 485                        break;
 486                }
 487
 488                if (!strcmp(arg, "--")) {
 489                        argv++;
 490                        argc--;
 491                        break;
 492                }
 493                if (!strcmp(arg, "-r")) {
 494                        recursive = 1;
 495                        continue;
 496                }
 497                if (!strcmp(arg, "-t")) {
 498                        recursive = show_tree_entry_in_recursive = 1;
 499                        continue;
 500                }
 501                if (!strcmp(arg, "-R")) {
 502                        diff_setup_opt |= DIFF_SETUP_REVERSE;
 503                        continue;
 504                }
 505                if (!strcmp(arg, "-p")) {
 506                        diff_output_format = DIFF_FORMAT_PATCH;
 507                        recursive = 1;
 508                        continue;
 509                }
 510                if (!strncmp(arg, "-S", 2)) {
 511                        pickaxe = arg + 2;
 512                        continue;
 513                }
 514                if (!strcmp(arg, "--pickaxe-all")) {
 515                        pickaxe_opts = DIFF_PICKAXE_ALL;
 516                        continue;
 517                }
 518                if (!strncmp(arg, "-M", 2)) {
 519                        detect_rename = DIFF_DETECT_RENAME;
 520                        diff_score_opt = diff_scoreopt_parse(arg);
 521                        continue;
 522                }
 523                if (!strncmp(arg, "-C", 2)) {
 524                        detect_rename = DIFF_DETECT_COPY;
 525                        diff_score_opt = diff_scoreopt_parse(arg);
 526                        continue;
 527                }
 528                if (!strncmp(arg, "-B", 2)) {
 529                        diff_break_opt = diff_scoreopt_parse(arg);
 530                        continue;
 531                }
 532                if (!strcmp(arg, "-z")) {
 533                        diff_output_format = DIFF_FORMAT_MACHINE;
 534                        continue;
 535                }
 536                if (!strcmp(arg, "-m")) {
 537                        ignore_merges = 0;
 538                        continue;
 539                }
 540                if (!strcmp(arg, "-s")) {
 541                        diff_output_format = DIFF_FORMAT_NO_OUTPUT;
 542                        continue;
 543                }
 544                if (!strcmp(arg, "-v")) {
 545                        verbose_header = 1;
 546                        header_prefix = "diff-tree ";
 547                        continue;
 548                }
 549                if (!strcmp(arg, "--stdin")) {
 550                        read_stdin = 1;
 551                        continue;
 552                }
 553                if (!strcmp(arg, "--root")) {
 554                        show_root_diff = 1;
 555                        continue;
 556                }
 557                usage(diff_tree_usage);
 558        }
 559
 560        if (argc > 0) {
 561                int i;
 562
 563                paths = argv;
 564                nr_paths = argc;
 565                pathlens = xmalloc(nr_paths * sizeof(int));
 566                for (i=0; i<nr_paths; i++)
 567                        pathlens[i] = strlen(paths[i]);
 568        }
 569
 570        switch (nr_sha1) {
 571        case 0:
 572                if (!read_stdin)
 573                        usage(diff_tree_usage);
 574                break;
 575        case 1:
 576                diff_tree_commit(sha1[0], NULL);
 577                break;
 578        case 2:
 579                diff_tree_sha1_top(sha1[0], sha1[1], "");
 580                break;
 581        }
 582
 583        if (!read_stdin)
 584                return 0;
 585
 586        if (detect_rename)
 587                diff_setup_opt |= (DIFF_SETUP_USE_SIZE_CACHE |
 588                                   DIFF_SETUP_USE_CACHE);
 589        while (fgets(line, sizeof(line), stdin))
 590                diff_tree_stdin(line);
 591
 592        return 0;
 593}