Andrew's git / gitweb.git / diff-tree.c
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diff-tree.con commit git-init-db: set up the full default environment (cad88fd)
   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 const char *header = NULL;
  18static const char *header_prefix = "";
  19
  20// What paths are we interested in?
  21static int nr_paths = 0;
  22static const char **paths = NULL;
  23static int *pathlens = NULL;
  24
  25static int diff_tree_sha1(const unsigned char *old, const unsigned char *new, const char *base);
  26
  27static void update_tree_entry(void **bufp, unsigned long *sizep)
  28{
  29        void *buf = *bufp;
  30        unsigned long size = *sizep;
  31        int len = strlen(buf) + 1 + 20;
  32
  33        if (size < len)
  34                die("corrupt tree file");
  35        *bufp = buf + len;
  36        *sizep = size - len;
  37}
  38
  39static const unsigned char *extract(void *tree, unsigned long size, const char **pathp, unsigned int *modep)
  40{
  41        int len = strlen(tree)+1;
  42        const unsigned char *sha1 = tree + len;
  43        const char *path = strchr(tree, ' ');
  44
  45        if (!path || size < len + 20 || sscanf(tree, "%o", modep) != 1)
  46                die("corrupt tree file");
  47        *pathp = path+1;
  48        return sha1;
  49}
  50
  51static char *malloc_base(const char *base, const char *path, int pathlen)
  52{
  53        int baselen = strlen(base);
  54        char *newbase = xmalloc(baselen + pathlen + 2);
  55        memcpy(newbase, base, baselen);
  56        memcpy(newbase + baselen, path, pathlen);
  57        memcpy(newbase + baselen + pathlen, "/", 2);
  58        return newbase;
  59}
  60
  61static void show_file(const char *prefix, void *tree, unsigned long size, const char *base);
  62static void show_tree(const char *prefix, void *tree, unsigned long size, const char *base);
  63
  64/* A file entry went away or appeared */
  65static void show_file(const char *prefix, void *tree, unsigned long size, const char *base)
  66{
  67        unsigned mode;
  68        const char *path;
  69        const unsigned char *sha1 = extract(tree, size, &path, &mode);
  70
  71        if (recursive && S_ISDIR(mode)) {
  72                char type[20];
  73                unsigned long size;
  74                char *newbase = malloc_base(base, path, strlen(path));
  75                void *tree;
  76
  77                tree = read_sha1_file(sha1, type, &size);
  78                if (!tree || strcmp(type, "tree"))
  79                        die("corrupt tree sha %s", sha1_to_hex(sha1));
  80
  81                show_tree(prefix, tree, size, newbase);
  82
  83                free(tree);
  84                free(newbase);
  85                return;
  86        }
  87
  88        diff_addremove(prefix[0], mode, sha1, base, path);
  89}
  90
  91static int compare_tree_entry(void *tree1, unsigned long size1, void *tree2, unsigned long size2, const char *base)
  92{
  93        unsigned mode1, mode2;
  94        const char *path1, *path2;
  95        const unsigned char *sha1, *sha2;
  96        int cmp, pathlen1, pathlen2;
  97
  98        sha1 = extract(tree1, size1, &path1, &mode1);
  99        sha2 = extract(tree2, size2, &path2, &mode2);
 100
 101        pathlen1 = strlen(path1);
 102        pathlen2 = strlen(path2);
 103        cmp = base_name_compare(path1, pathlen1, mode1, path2, pathlen2, mode2);
 104        if (cmp < 0) {
 105                show_file("-", tree1, size1, base);
 106                return -1;
 107        }
 108        if (cmp > 0) {
 109                show_file("+", tree2, size2, base);
 110                return 1;
 111        }
 112        if (!memcmp(sha1, sha2, 20) && mode1 == mode2)
 113                return 0;
 114
 115        /*
 116         * If the filemode has changed to/from a directory from/to a regular
 117         * file, we need to consider it a remove and an add.
 118         */
 119        if (S_ISDIR(mode1) != S_ISDIR(mode2)) {
 120                show_file("-", tree1, size1, base);
 121                show_file("+", tree2, size2, base);
 122                return 0;
 123        }
 124
 125        if (recursive && S_ISDIR(mode1)) {
 126                int retval;
 127                char *newbase = malloc_base(base, path1, pathlen1);
 128                if (show_tree_entry_in_recursive)
 129                        diff_change(mode1, mode2, sha1, sha2, base, path1);
 130                retval = diff_tree_sha1(sha1, sha2, newbase);
 131                free(newbase);
 132                return retval;
 133        }
 134
 135        diff_change(mode1, mode2, sha1, sha2, base, path1);
 136        return 0;
 137}
 138
 139static int interesting(void *tree, unsigned long size, const char *base)
 140{
 141        const char *path;
 142        unsigned mode;
 143        int i;
 144        int baselen, pathlen;
 145
 146        if (!nr_paths)
 147                return 1;
 148
 149        (void)extract(tree, size, &path, &mode);
 150
 151        pathlen = strlen(path);
 152        baselen = strlen(base);
 153
 154        for (i=0; i < nr_paths; i++) {
 155                const char *match = paths[i];
 156                int matchlen = pathlens[i];
 157
 158                if (baselen >= matchlen) {
 159                        /* If it doesn't match, move along... */
 160                        if (strncmp(base, match, matchlen))
 161                                continue;
 162
 163                        /* The base is a subdirectory of a path which was specified. */
 164                        return 1;
 165                }
 166
 167                /* Does the base match? */
 168                if (strncmp(base, match, baselen))
 169                        continue;
 170
 171                match += baselen;
 172                matchlen -= baselen;
 173
 174                if (pathlen > matchlen)
 175                        continue;
 176
 177                if (matchlen > pathlen) {
 178                        if (match[pathlen] != '/')
 179                                continue;
 180                        if (!S_ISDIR(mode))
 181                                continue;
 182                }
 183
 184                if (strncmp(path, match, pathlen))
 185                        continue;
 186
 187                return 1;
 188        }
 189        return 0; /* No matches */
 190}
 191
 192/* A whole sub-tree went away or appeared */
 193static void show_tree(const char *prefix, void *tree, unsigned long size, const char *base)
 194{
 195        while (size) {
 196                if (interesting(tree, size, base))
 197                        show_file(prefix, tree, size, base);
 198                update_tree_entry(&tree, &size);
 199        }
 200}
 201
 202static int diff_tree(void *tree1, unsigned long size1, void *tree2, unsigned long size2, const char *base)
 203{
 204        while (size1 | size2) {
 205                if (nr_paths && size1 && !interesting(tree1, size1, base)) {
 206                        update_tree_entry(&tree1, &size1);
 207                        continue;
 208                }
 209                if (nr_paths && size2 && !interesting(tree2, size2, base)) {
 210                        update_tree_entry(&tree2, &size2);
 211                        continue;
 212                }
 213                if (!size1) {
 214                        show_file("+", tree2, size2, base);
 215                        update_tree_entry(&tree2, &size2);
 216                        continue;
 217                }
 218                if (!size2) {
 219                        show_file("-", tree1, size1, base);
 220                        update_tree_entry(&tree1, &size1);
 221                        continue;
 222                }
 223                switch (compare_tree_entry(tree1, size1, tree2, size2, base)) {
 224                case -1:
 225                        update_tree_entry(&tree1, &size1);
 226                        continue;
 227                case 0:
 228                        update_tree_entry(&tree1, &size1);
 229                        /* Fallthrough */
 230                case 1:
 231                        update_tree_entry(&tree2, &size2);
 232                        continue;
 233                }
 234                die("git-diff-tree: internal error");
 235        }
 236        return 0;
 237}
 238
 239static int diff_tree_sha1(const unsigned char *old, const unsigned char *new, const char *base)
 240{
 241        void *tree1, *tree2;
 242        unsigned long size1, size2;
 243        int retval;
 244
 245        tree1 = read_object_with_reference(old, "tree", &size1, NULL);
 246        if (!tree1)
 247                die("unable to read source tree (%s)", sha1_to_hex(old));
 248        tree2 = read_object_with_reference(new, "tree", &size2, NULL);
 249        if (!tree2)
 250                die("unable to read destination tree (%s)", sha1_to_hex(new));
 251        retval = diff_tree(tree1, size1, tree2, size2, base);
 252        free(tree1);
 253        free(tree2);
 254        return retval;
 255}
 256
 257static void call_diff_setup(void)
 258{
 259        diff_setup(diff_setup_opt);
 260}
 261
 262static int call_diff_flush(void)
 263{
 264        if (detect_rename)
 265                diffcore_rename(detect_rename, diff_score_opt);
 266        if (pickaxe)
 267                diffcore_pickaxe(pickaxe, pickaxe_opts);
 268        if (diff_queue_is_empty()) {
 269                diff_flush(DIFF_FORMAT_NO_OUTPUT, 0);
 270                return 0;
 271        }
 272        if (header) {
 273                const char *fmt = "%s";
 274                if (diff_output_format == DIFF_FORMAT_MACHINE)
 275                        fmt = "%s%c";
 276                
 277                printf(fmt, header, 0);
 278                header = NULL;
 279        }
 280        diff_flush(diff_output_format, 1);
 281        return 1;
 282}
 283
 284static int diff_tree_sha1_top(const unsigned char *old,
 285                              const unsigned char *new, const char *base)
 286{
 287        int ret;
 288
 289        call_diff_setup();
 290        ret = diff_tree_sha1(old, new, base);
 291        call_diff_flush();
 292        return ret;
 293}
 294
 295static int diff_root_tree(const unsigned char *new, const char *base)
 296{
 297        int retval;
 298        void *tree;
 299        unsigned long size;
 300
 301        call_diff_setup();
 302        tree = read_object_with_reference(new, "tree", &size, NULL);
 303        if (!tree)
 304                die("unable to read root tree (%s)", sha1_to_hex(new));
 305        retval = diff_tree("", 0, tree, size, base);
 306        free(tree);
 307        call_diff_flush();
 308        return retval;
 309}
 310
 311static int get_one_line(const char *msg, unsigned long len)
 312{
 313        int ret = 0;
 314
 315        while (len--) {
 316                ret++;
 317                if (*msg++ == '\n')
 318                        break;
 319        }
 320        return ret;
 321}
 322
 323static int add_author_info(char *buf, const char *line, int len)
 324{
 325        char *date;
 326        unsigned int namelen;
 327        unsigned long time;
 328        int tz;
 329
 330        line += strlen("author ");
 331        date = strchr(line, '>');
 332        if (!date)
 333                return 0;
 334        namelen = ++date - line;
 335        time = strtoul(date, &date, 10);
 336        tz = strtol(date, NULL, 10);
 337
 338        return sprintf(buf, "Author: %.*s\nDate:   %s\n",
 339                namelen, line,
 340                show_date(time, tz));
 341}
 342
 343static char *generate_header(const char *commit, const char *parent, const char *msg, unsigned long len)
 344{
 345        static char this_header[16384];
 346        int offset;
 347
 348        offset = sprintf(this_header, "%s%s (from %s)\n", header_prefix, commit, parent);
 349        if (verbose_header) {
 350                int hdr = 1;
 351
 352                for (;;) {
 353                        const char *line = msg;
 354                        int linelen = get_one_line(msg, len);
 355
 356                        if (!linelen)
 357                                break;
 358
 359                        /*
 360                         * We want some slop for indentation and a possible
 361                         * final "...". Thus the "+ 20".
 362                         */
 363                        if (offset + linelen + 20 > sizeof(this_header)) {
 364                                memcpy(this_header + offset, "    ...\n", 8);
 365                                offset += 8;
 366                                break;
 367                        }
 368
 369                        msg += linelen;
 370                        len -= linelen;
 371                        if (linelen == 1)
 372                                hdr = 0;
 373                        if (hdr) {
 374                                if (!memcmp(line, "author ", 7))
 375                                        offset += add_author_info(this_header + offset, line, linelen);
 376                                continue;
 377                        }
 378                        memset(this_header + offset, ' ', 4);
 379                        memcpy(this_header + offset + 4, line, linelen);
 380                        offset += linelen + 4;
 381                }
 382                /* Make sure there is an EOLN */
 383                if (this_header[offset-1] != '\n')
 384                        this_header[offset++] = '\n';
 385                /* Add _another_ EOLN if we are doing diff output */
 386                this_header[offset++] = '\n';
 387                this_header[offset] = 0;
 388        }
 389
 390        return this_header;
 391}
 392
 393static int diff_tree_commit(const unsigned char *commit, const char *name)
 394{
 395        unsigned long size, offset;
 396        char *buf = read_object_with_reference(commit, "commit", &size, NULL);
 397
 398        if (!buf)
 399                return -1;
 400
 401        if (!name) {
 402                static char commit_name[60];
 403                strcpy(commit_name, sha1_to_hex(commit));
 404                name = commit_name;
 405        }
 406
 407        /* Root commit? */
 408        if (show_root_diff && memcmp(buf + 46, "parent ", 7)) {
 409                header = generate_header(name, "root", buf, size);
 410                diff_root_tree(commit, "");
 411        }
 412
 413        /* More than one parent? */
 414        if (ignore_merges) {
 415                if (!memcmp(buf + 46 + 48, "parent ", 7))
 416                        return 0;
 417        }
 418
 419        offset = 46;
 420        while (offset + 48 < size && !memcmp(buf + offset, "parent ", 7)) {
 421                unsigned char parent[20];
 422                if (get_sha1_hex(buf + offset + 7, parent))
 423                        return -1;
 424                header = generate_header(name, sha1_to_hex(parent), buf, size);
 425                diff_tree_sha1_top(parent, commit, "");
 426                if (!header && verbose_header) {
 427                        header_prefix = "\ndiff-tree ";
 428                        /*
 429                         * Don't print multiple merge entries if we
 430                         * don't print the diffs.
 431                         */
 432                }
 433                offset += 48;
 434        }
 435        return 0;
 436}
 437
 438static int diff_tree_stdin(char *line)
 439{
 440        int len = strlen(line);
 441        unsigned char commit[20], parent[20];
 442        static char this_header[1000];
 443
 444        if (!len || line[len-1] != '\n')
 445                return -1;
 446        line[len-1] = 0;
 447        if (get_sha1_hex(line, commit))
 448                return -1;
 449        if (isspace(line[40]) && !get_sha1_hex(line+41, parent)) {
 450                line[40] = 0;
 451                line[81] = 0;
 452                sprintf(this_header, "%s (from %s)\n", line, line+41);
 453                header = this_header;
 454                return diff_tree_sha1_top(parent, commit, "");
 455        }
 456        line[40] = 0;
 457        return diff_tree_commit(commit, line);
 458}
 459
 460static char *diff_tree_usage =
 461"git-diff-tree [-p] [-r] [-z] [--stdin] [-M] [-C] [-R] [-S<string>] [-m] [-s] [-v] [-t] <tree-ish> <tree-ish>";
 462
 463int main(int argc, const char **argv)
 464{
 465        int nr_sha1;
 466        char line[1000];
 467        unsigned char sha1[2][20];
 468
 469        nr_sha1 = 0;
 470        for (;;) {
 471                const char *arg;
 472
 473                argv++;
 474                argc--;
 475                arg = *argv;
 476                if (!arg)
 477                        break;
 478
 479                if (*arg != '-') {
 480                        if (nr_sha1 < 2 && !get_sha1(arg, sha1[nr_sha1])) {
 481                                nr_sha1++;
 482                                continue;
 483                        }
 484                        break;
 485                }
 486
 487                if (!strcmp(arg, "--")) {
 488                        argv++;
 489                        argc--;
 490                        break;
 491                }
 492                if (!strcmp(arg, "-r")) {
 493                        recursive = 1;
 494                        continue;
 495                }
 496                if (!strcmp(arg, "-t")) {
 497                        recursive = show_tree_entry_in_recursive = 1;
 498                        continue;
 499                }
 500                if (!strcmp(arg, "-R")) {
 501                        diff_setup_opt |= DIFF_SETUP_REVERSE;
 502                        continue;
 503                }
 504                if (!strcmp(arg, "-p")) {
 505                        diff_output_format = DIFF_FORMAT_PATCH;
 506                        recursive = 1;
 507                        continue;
 508                }
 509                if (!strncmp(arg, "-S", 2)) {
 510                        pickaxe = arg + 2;
 511                        continue;
 512                }
 513                if (!strcmp(arg, "--pickaxe-all")) {
 514                        pickaxe_opts = DIFF_PICKAXE_ALL;
 515                        continue;
 516                }
 517                if (!strncmp(arg, "-M", 2)) {
 518                        detect_rename = DIFF_DETECT_RENAME;
 519                        diff_score_opt = diff_scoreopt_parse(arg);
 520                        continue;
 521                }
 522                if (!strncmp(arg, "-C", 2)) {
 523                        detect_rename = DIFF_DETECT_COPY;
 524                        diff_score_opt = diff_scoreopt_parse(arg);
 525                        continue;
 526                }
 527                if (!strcmp(arg, "-z")) {
 528                        diff_output_format = DIFF_FORMAT_MACHINE;
 529                        continue;
 530                }
 531                if (!strcmp(arg, "-m")) {
 532                        ignore_merges = 0;
 533                        continue;
 534                }
 535                if (!strcmp(arg, "-s")) {
 536                        diff_output_format = DIFF_FORMAT_NO_OUTPUT;
 537                        continue;
 538                }
 539                if (!strcmp(arg, "-v")) {
 540                        verbose_header = 1;
 541                        header_prefix = "diff-tree ";
 542                        continue;
 543                }
 544                if (!strcmp(arg, "--stdin")) {
 545                        read_stdin = 1;
 546                        continue;
 547                }
 548                if (!strcmp(arg, "--root")) {
 549                        show_root_diff = 1;
 550                        continue;
 551                }
 552                usage(diff_tree_usage);
 553        }
 554
 555        if (argc > 0) {
 556                int i;
 557
 558                paths = argv;
 559                nr_paths = argc;
 560                pathlens = xmalloc(nr_paths * sizeof(int));
 561                for (i=0; i<nr_paths; i++)
 562                        pathlens[i] = strlen(paths[i]);
 563        }
 564
 565        switch (nr_sha1) {
 566        case 0:
 567                if (!read_stdin)
 568                        usage(diff_tree_usage);
 569                break;
 570        case 1:
 571                diff_tree_commit(sha1[0], NULL);
 572                break;
 573        case 2:
 574                diff_tree_sha1_top(sha1[0], sha1[1], "");
 575                break;
 576        }
 577
 578        if (!read_stdin)
 579                return 0;
 580
 581        if (detect_rename)
 582                diff_setup_opt |= (DIFF_SETUP_USE_SIZE_CACHE |
 583                                   DIFF_SETUP_USE_CACHE);
 584        while (fgets(line, sizeof(line), stdin))
 585                diff_tree_stdin(line);
 586
 587        return 0;
 588}