blame.c

   1 /*
   2  * Copyright (C) 2006, Fredrik Kuivinen <freku045@student.liu.se>
   3  */
   4
   5 #include <assert.h>
   6 #include <time.h>
   7 #include <sys/time.h>
   8 #include <math.h>
   9
  10 #include "cache.h"
  11 #include "refs.h"
  12 #include "tag.h"
  13 #include "commit.h"
  14 #include "tree.h"
  15 #include "blob.h"
  16 #include "diff.h"
  17 #include "diffcore.h"
  18 #include "revision.h"
  19 #include "xdiff-interface.h"
  20 #include "quote.h"
  21
  22 #ifndef DEBUG
  23 #define DEBUG 0
  24 #endif
  25
  26 static const char blame_usage[] =
  27 "git-blame [-c] [-l] [-t] [-f] [-n] [-p] [-S <revs-file>] [--] file [commit]\n"
  28 "  -c, --compatibility Use the same output mode as git-annotate (Default: off)\n"
  29 "  -l, --long          Show long commit SHA1 (Default: off)\n"
  30 "  -t, --time          Show raw timestamp (Default: off)\n"
  31 "  -f, --show-name     Show original filename (Default: auto)\n"
  32 "  -n, --show-number   Show original linenumber (Default: off)\n"
  33 "  -p, --porcelain     Show in a format designed for machine consumption\n"
  34 "  -S revs-file        Use revisions from revs-file instead of calling git-rev-list\n"
  35 "  -h, --help          This message";
  36
  37 static struct commit **blame_lines;
  38 static int num_blame_lines;
  39 static char *blame_contents;
  40 static int blame_len;
  41
  42 struct util_info {
  43         int *line_map;
  44         unsigned char sha1[20]; /* blob sha, not commit! */
  45         char *buf;
  46         unsigned long size;
  47         int num_lines;
  48         const char *pathname;
  49         unsigned meta_given:1;
  50
  51         void *topo_data;
  52 };
  53
  54 struct chunk {
  55         int off1, len1; /* --- */
  56         int off2, len2; /* +++ */
  57 };
  58
  59 struct patch {
  60         struct chunk *chunks;
  61         int num;
  62 };
  63
  64 static void get_blob(struct commit *commit);
  65
  66 /* Only used for statistics */
  67 static int num_get_patch;
  68 static int num_commits;
  69 static int patch_time;
  70
  71 struct blame_diff_state {
  72         struct xdiff_emit_state xm;
  73         struct patch *ret;
  74 };
  75
  76 static void process_u0_diff(void *state_, char *line, unsigned long len)
  77 {
  78         struct blame_diff_state *state = state_;
  79         struct chunk *chunk;
  80
  81         if (len < 4 || line[0] != '@' || line[1] != '@')
  82                 return;
  83
  84         if (DEBUG)
  85                 printf("chunk line: %.*s", (int)len, line);
  86         state->ret->num++;
  87         state->ret->chunks = xrealloc(state->ret->chunks,
  88                                       sizeof(struct chunk) * state->ret->num);
  89         chunk = &state->ret->chunks[state->ret->num - 1];
  90
  91         assert(!strncmp(line, "@@ -", 4));
  92
  93         if (parse_hunk_header(line, len,
  94                               &chunk->off1, &chunk->len1,
  95                               &chunk->off2, &chunk->len2)) {
  96                 state->ret->num--;
  97                 return;
  98         }
  99
 100         if (chunk->len1 == 0)
 101                 chunk->off1++;
 102         if (chunk->len2 == 0)
 103                 chunk->off2++;
 104
 105         if (chunk->off1 > 0)
 106                 chunk->off1--;
 107         if (chunk->off2 > 0)
 108                 chunk->off2--;
 109
 110         assert(chunk->off1 >= 0);
 111         assert(chunk->off2 >= 0);
 112 }
 113
 114 static struct patch *get_patch(struct commit *commit, struct commit *other)
 115 {
 116         struct blame_diff_state state;
 117         xpparam_t xpp;
 118         xdemitconf_t xecfg;
 119         mmfile_t file_c, file_o;
 120         xdemitcb_t ecb;
 121         struct util_info *info_c = (struct util_info *)commit->util;
 122         struct util_info *info_o = (struct util_info *)other->util;
 123         struct timeval tv_start, tv_end;
 124
 125         get_blob(commit);
 126         file_c.ptr = info_c->buf;
 127         file_c.size = info_c->size;
 128
 129         get_blob(other);
 130         file_o.ptr = info_o->buf;
 131         file_o.size = info_o->size;
 132
 133         gettimeofday(&tv_start, NULL);
 134
 135         xpp.flags = XDF_NEED_MINIMAL;
 136         xecfg.ctxlen = 0;
 137         xecfg.flags = 0;
 138         ecb.outf = xdiff_outf;
 139         ecb.priv = &state;
 140         memset(&state, 0, sizeof(state));
 141         state.xm.consume = process_u0_diff;
 142         state.ret = xmalloc(sizeof(struct patch));
 143         state.ret->chunks = NULL;
 144         state.ret->num = 0;
 145
 146         xdl_diff(&file_c, &file_o, &xpp, &xecfg, &ecb);
 147
 148         gettimeofday(&tv_end, NULL);
 149         patch_time += 1000000 * (tv_end.tv_sec - tv_start.tv_sec) +
 150                 tv_end.tv_usec - tv_start.tv_usec;
 151
 152         num_get_patch++;
 153         return state.ret;
 154 }
 155
 156 static void free_patch(struct patch *p)
 157 {
 158         free(p->chunks);
 159         free(p);
 160 }
 161
 162 static int get_blob_sha1_internal(const unsigned char *sha1, const char *base,
 163                                   int baselen, const char *pathname,
 164                                   unsigned mode, int stage);
 165
 166 static unsigned char blob_sha1[20];
 167 static const char *blame_file;
 168 static int get_blob_sha1(struct tree *t, const char *pathname,
 169                          unsigned char *sha1)
 170 {
 171         const char *pathspec[2];
 172         blame_file = pathname;
 173         pathspec[0] = pathname;
 174         pathspec[1] = NULL;
 175         hashclr(blob_sha1);
 176         read_tree_recursive(t, "", 0, 0, pathspec, get_blob_sha1_internal);
 177
 178         if (is_null_sha1(blob_sha1))
 179                 return -1;
 180
 181         hashcpy(sha1, blob_sha1);
 182         return 0;
 183 }
 184
 185 static int get_blob_sha1_internal(const unsigned char *sha1, const char *base,
 186                                   int baselen, const char *pathname,
 187                                   unsigned mode, int stage)
 188 {
 189         if (S_ISDIR(mode))
 190                 return READ_TREE_RECURSIVE;
 191
 192         if (strncmp(blame_file, base, baselen) ||
 193             strcmp(blame_file + baselen, pathname))
 194                 return -1;
 195
 196         hashcpy(blob_sha1, sha1);
 197         return -1;
 198 }
 199
 200 static void get_blob(struct commit *commit)
 201 {
 202         struct util_info *info = commit->util;
 203         char type[20];
 204
 205         if (info->buf)
 206                 return;
 207
 208         info->buf = read_sha1_file(info->sha1, type, &info->size);
 209
 210         assert(!strcmp(type, blob_type));
 211 }
 212
 213 /* For debugging only */
 214 static void print_patch(struct patch *p)
 215 {
 216         int i;
 217         printf("Num chunks: %d\n", p->num);
 218         for (i = 0; i < p->num; i++) {
 219                 printf("%d,%d %d,%d\n", p->chunks[i].off1, p->chunks[i].len1,
 220                        p->chunks[i].off2, p->chunks[i].len2);
 221         }
 222 }
 223
 224 #if DEBUG
 225 /* For debugging only */
 226 static void print_map(struct commit *cmit, struct commit *other)
 227 {
 228         struct util_info *util = cmit->util;
 229         struct util_info *util2 = other->util;
 230
 231         int i;
 232         int max =
 233             util->num_lines >
 234             util2->num_lines ? util->num_lines : util2->num_lines;
 235         int num;
 236
 237         if (print_map == NULL)
 238                 ; /* to avoid "unused function" warning */
 239
 240         for (i = 0; i < max; i++) {
 241                 printf("i: %d ", i);
 242                 num = -1;
 243
 244                 if (i < util->num_lines) {
 245                         num = util->line_map[i];
 246                         printf("%d\t", num);
 247                 }
 248                 else
 249                         printf("\t");
 250
 251                 if (i < util2->num_lines) {
 252                         int num2 = util2->line_map[i];
 253                         printf("%d\t", num2);
 254                         if (num != -1 && num2 != num)
 255                                 printf("---");
 256                 }
 257                 else
 258                         printf("\t");
 259
 260                 printf("\n");
 261         }
 262 }
 263 #endif
 264
 265 /* p is a patch from commit to other. */
 266 static void fill_line_map(struct commit *commit, struct commit *other,
 267                           struct patch *p)
 268 {
 269         struct util_info *util = commit->util;
 270         struct util_info *util2 = other->util;
 271         int *map = util->line_map;
 272         int *map2 = util2->line_map;
 273         int cur_chunk = 0;
 274         int i1, i2;
 275
 276         if (DEBUG) {
 277                 if (p->num)
 278                         print_patch(p);
 279                 printf("num lines 1: %d num lines 2: %d\n", util->num_lines,
 280                        util2->num_lines);
 281         }
 282
 283         for (i1 = 0, i2 = 0; i1 < util->num_lines; i1++, i2++) {
 284                 struct chunk *chunk = NULL;
 285                 if (cur_chunk < p->num)
 286                         chunk = &p->chunks[cur_chunk];
 287
 288                 if (chunk && chunk->off1 == i1) {
 289                         if (DEBUG && i2 != chunk->off2)
 290                                 printf("i2: %d off2: %d\n", i2, chunk->off2);
 291
 292                         assert(i2 == chunk->off2);
 293
 294                         i1--;
 295                         i2--;
 296                         if (chunk->len1 > 0)
 297                                 i1 += chunk->len1;
 298
 299                         if (chunk->len2 > 0)
 300                                 i2 += chunk->len2;
 301
 302                         cur_chunk++;
 303                 }
 304                 else {
 305                         if (i2 >= util2->num_lines)
 306                                 break;
 307
 308                         if (map[i1] != map2[i2] && map[i1] != -1) {
 309                                 if (DEBUG)
 310                                         printf("map: i1: %d %d %p i2: %d %d %p\n",
 311                                                i1, map[i1],
 312                                                (void *) (i1 != -1 ? blame_lines[map[i1]] : NULL),
 313                                                i2, map2[i2],
 314                                                (void *) (i2 != -1 ? blame_lines[map2[i2]] : NULL));
 315                                 if (map2[i2] != -1 &&
 316                                     blame_lines[map[i1]] &&
 317                                     !blame_lines[map2[i2]])
 318                                         map[i1] = map2[i2];
 319                         }
 320
 321                         if (map[i1] == -1 && map2[i2] != -1)
 322                                 map[i1] = map2[i2];
 323                 }
 324
 325                 if (DEBUG > 1)
 326                         printf("l1: %d l2: %d i1: %d i2: %d\n",
 327                                map[i1], map2[i2], i1, i2);
 328         }
 329 }
 330
 331 static int map_line(struct commit *commit, int line)
 332 {
 333         struct util_info *info = commit->util;
 334         assert(line >= 0 && line < info->num_lines);
 335         return info->line_map[line];
 336 }
 337
 338 static struct util_info *get_util(struct commit *commit)
 339 {
 340         struct util_info *util = commit->util;
 341
 342         if (util)
 343                 return util;
 344
 345         util = xcalloc(1, sizeof(struct util_info));
 346         util->num_lines = -1;
 347         commit->util = util;
 348         return util;
 349 }
 350
 351 static int fill_util_info(struct commit *commit)
 352 {
 353         struct util_info *util = commit->util;
 354
 355         assert(util);
 356         assert(util->pathname);
 357
 358         return !!get_blob_sha1(commit->tree, util->pathname, util->sha1);
 359 }
 360
 361 static void alloc_line_map(struct commit *commit)
 362 {
 363         struct util_info *util = commit->util;
 364         int i;
 365
 366         if (util->line_map)
 367                 return;
 368
 369         get_blob(commit);
 370
 371         util->num_lines = 0;
 372         for (i = 0; i < util->size; i++) {
 373                 if (util->buf[i] == '\n')
 374                         util->num_lines++;
 375         }
 376         if (util->buf[util->size - 1] != '\n')
 377                 util->num_lines++;
 378
 379         util->line_map = xmalloc(sizeof(int) * util->num_lines);
 380
 381         for (i = 0; i < util->num_lines; i++)
 382                 util->line_map[i] = -1;
 383 }
 384
 385 static void init_first_commit(struct commit *commit, const char *filename)
 386 {
 387         struct util_info *util = commit->util;
 388         int i;
 389
 390         util->pathname = filename;
 391         if (fill_util_info(commit))
 392                 die("fill_util_info failed");
 393
 394         alloc_line_map(commit);
 395
 396         util = commit->util;
 397
 398         for (i = 0; i < util->num_lines; i++)
 399                 util->line_map[i] = i;
 400 }
 401
 402 static void process_commits(struct rev_info *rev, const char *path,
 403                             struct commit **initial)
 404 {
 405         int i;
 406         struct util_info *util;
 407         int lines_left;
 408         int *blame_p;
 409         int *new_lines;
 410         int new_lines_len;
 411
 412         struct commit *commit = get_revision(rev);
 413         assert(commit);
 414         init_first_commit(commit, path);
 415
 416         util = commit->util;
 417         num_blame_lines = util->num_lines;
 418         blame_lines = xmalloc(sizeof(struct commit *) * num_blame_lines);
 419         blame_contents = util->buf;
 420         blame_len = util->size;
 421
 422         for (i = 0; i < num_blame_lines; i++)
 423                 blame_lines[i] = NULL;
 424
 425         lines_left = num_blame_lines;
 426         blame_p = xmalloc(sizeof(int) * num_blame_lines);
 427         new_lines = xmalloc(sizeof(int) * num_blame_lines);
 428         do {
 429                 struct commit_list *parents;
 430                 int num_parents;
 431                 struct util_info *util;
 432
 433                 if (DEBUG)
 434                         printf("\nProcessing commit: %d %s\n", num_commits,
 435                                sha1_to_hex(commit->object.sha1));
 436
 437                 if (lines_left == 0)
 438                         return;
 439
 440                 num_commits++;
 441                 memset(blame_p, 0, sizeof(int) * num_blame_lines);
 442                 new_lines_len = 0;
 443                 num_parents = 0;
 444                 for (parents = commit->parents;
 445                      parents != NULL; parents = parents->next)
 446                         num_parents++;
 447
 448                 if (num_parents == 0)
 449                         *initial = commit;
 450
 451                 if (fill_util_info(commit))
 452                         continue;
 453
 454                 alloc_line_map(commit);
 455                 util = commit->util;
 456
 457                 for (parents = commit->parents;
 458                      parents != NULL; parents = parents->next) {
 459                         struct commit *parent = parents->item;
 460                         struct patch *patch;
 461
 462                         if (parse_commit(parent) < 0)
 463                                 die("parse_commit error");
 464
 465                         if (DEBUG)
 466                                 printf("parent: %s\n",
 467                                        sha1_to_hex(parent->object.sha1));
 468
 469                         if (fill_util_info(parent)) {
 470                                 num_parents--;
 471                                 continue;
 472                         }
 473
 474                         patch = get_patch(parent, commit);
 475                         alloc_line_map(parent);
 476                         fill_line_map(parent, commit, patch);
 477
 478                         for (i = 0; i < patch->num; i++) {
 479                             int l;
 480                             for (l = 0; l < patch->chunks[i].len2; l++) {
 481                                 int mapped_line =
 482                                     map_line(commit, patch->chunks[i].off2 + l);
 483                                 if (mapped_line != -1) {
 484                                     blame_p[mapped_line]++;
 485                                     if (blame_p[mapped_line] == num_parents)
 486                                         new_lines[new_lines_len++] = mapped_line;
 487                                 }
 488                             }
 489                         }
 490                         free_patch(patch);
 491                 }
 492
 493                 if (DEBUG)
 494                         printf("parents: %d\n", num_parents);
 495
 496                 for (i = 0; i < new_lines_len; i++) {
 497                         int mapped_line = new_lines[i];
 498                         if (blame_lines[mapped_line] == NULL) {
 499                                 blame_lines[mapped_line] = commit;
 500                                 lines_left--;
 501                                 if (DEBUG)
 502                                         printf("blame: mapped: %d i: %d\n",
 503                                                mapped_line, i);
 504                         }
 505                 }
 506         } while ((commit = get_revision(rev)) != NULL);
 507 }
 508
 509 static int compare_tree_path(struct rev_info *revs,
 510                              struct commit *c1, struct commit *c2)
 511 {
 512         int ret;
 513         const char *paths[2];
 514         struct util_info *util = c2->util;
 515         paths[0] = util->pathname;
 516         paths[1] = NULL;
 517
 518         diff_tree_setup_paths(get_pathspec(revs->prefix, paths),
 519                               &revs->pruning);
 520         ret = rev_compare_tree(revs, c1->tree, c2->tree);
 521         diff_tree_release_paths(&revs->pruning);
 522         return ret;
 523 }
 524
 525 static int same_tree_as_empty_path(struct rev_info *revs, struct tree *t1,
 526                                    const char *path)
 527 {
 528         int ret;
 529         const char *paths[2];
 530         paths[0] = path;
 531         paths[1] = NULL;
 532
 533         diff_tree_setup_paths(get_pathspec(revs->prefix, paths),
 534                               &revs->pruning);
 535         ret = rev_same_tree_as_empty(revs, t1);
 536         diff_tree_release_paths(&revs->pruning);
 537         return ret;
 538 }
 539
 540 static const char *find_rename(struct commit *commit, struct commit *parent)
 541 {
 542         struct util_info *cutil = commit->util;
 543         struct diff_options diff_opts;
 544         const char *paths[1];
 545         int i;
 546
 547         if (DEBUG) {
 548                 printf("find_rename commit: %s ",
 549                        sha1_to_hex(commit->object.sha1));
 550                 puts(sha1_to_hex(parent->object.sha1));
 551         }
 552
 553         diff_setup(&diff_opts);
 554         diff_opts.recursive = 1;
 555         diff_opts.detect_rename = DIFF_DETECT_RENAME;
 556         paths[0] = NULL;
 557         diff_tree_setup_paths(paths, &diff_opts);
 558         if (diff_setup_done(&diff_opts) < 0)
 559                 die("diff_setup_done failed");
 560
 561         diff_tree_sha1(commit->tree->object.sha1, parent->tree->object.sha1,
 562                        "", &diff_opts);
 563         diffcore_std(&diff_opts);
 564
 565         for (i = 0; i < diff_queued_diff.nr; i++) {
 566                 struct diff_filepair *p = diff_queued_diff.queue[i];
 567
 568                 if (p->status == 'R' &&
 569                     !strcmp(p->one->path, cutil->pathname)) {
 570                         if (DEBUG)
 571                                 printf("rename %s -> %s\n",
 572                                        p->one->path, p->two->path);
 573                         return p->two->path;
 574                 }
 575         }
 576
 577         return 0;
 578 }
 579
 580 static void simplify_commit(struct rev_info *revs, struct commit *commit)
 581 {
 582         struct commit_list **pp, *parent;
 583
 584         if (!commit->tree)
 585                 return;
 586
 587         if (!commit->parents) {
 588                 struct util_info *util = commit->util;
 589                 if (!same_tree_as_empty_path(revs, commit->tree,
 590                                              util->pathname))
 591                         commit->object.flags |= TREECHANGE;
 592                 return;
 593         }
 594
 595         pp = &commit->parents;
 596         while ((parent = *pp) != NULL) {
 597                 struct commit *p = parent->item;
 598
 599                 if (p->object.flags & UNINTERESTING) {
 600                         pp = &parent->next;
 601                         continue;
 602                 }
 603
 604                 parse_commit(p);
 605                 switch (compare_tree_path(revs, p, commit)) {
 606                 case REV_TREE_SAME:
 607                         parent->next = NULL;
 608                         commit->parents = parent;
 609                         get_util(p)->pathname = get_util(commit)->pathname;
 610                         return;
 611
 612                 case REV_TREE_NEW:
 613                 {
 614                         struct util_info *util = commit->util;
 615                         if (revs->remove_empty_trees &&
 616                             same_tree_as_empty_path(revs, p->tree,
 617                                                     util->pathname)) {
 618                                 const char *new_name = find_rename(commit, p);
 619                                 if (new_name) {
 620                                         struct util_info *putil = get_util(p);
 621                                         if (!putil->pathname)
 622                                                 putil->pathname = xstrdup(new_name);
 623                                 }
 624                                 else {
 625                                         *pp = parent->next;
 626                                         continue;
 627                                 }
 628                         }
 629                 }
 630
 631                 /* fallthrough */
 632                 case REV_TREE_DIFFERENT:
 633                         pp = &parent->next;
 634                         if (!get_util(p)->pathname)
 635                                 get_util(p)->pathname =
 636                                         get_util(commit)->pathname;
 637                         continue;
 638                 }
 639                 die("bad tree compare for commit %s",
 640                     sha1_to_hex(commit->object.sha1));
 641         }
 642         commit->object.flags |= TREECHANGE;
 643 }
 644
 645 struct commit_info
 646 {
 647         char *author;
 648         char *author_mail;
 649         unsigned long author_time;
 650         char *author_tz;
 651
 652         /* filled only when asked for details */
 653         char *committer;
 654         char *committer_mail;
 655         unsigned long committer_time;
 656         char *committer_tz;
 657
 658         char *summary;
 659 };
 660
 661 static void get_ac_line(const char *inbuf, const char *what,
 662                         int bufsz, char *person, char **mail,
 663                         unsigned long *time, char **tz)
 664 {
 665         int len;
 666         char *tmp, *endp;
 667
 668         tmp = strstr(inbuf, what);
 669         if (!tmp)
 670                 goto error_out;
 671         tmp += strlen(what);
 672         endp = strchr(tmp, '\n');
 673         if (!endp)
 674                 len = strlen(tmp);
 675         else
 676                 len = endp - tmp;
 677         if (bufsz <= len) {
 678         error_out:
 679                 /* Ugh */
 680                 person = *mail = *tz = "(unknown)";
 681                 *time = 0;
 682                 return;
 683         }
 684         memcpy(person, tmp, len);
 685
 686         tmp = person;
 687         tmp += len;
 688         *tmp = 0;
 689         while (*tmp != ' ')
 690                 tmp--;
 691         *tz = tmp+1;
 692
 693         *tmp = 0;
 694         while (*tmp != ' ')
 695                 tmp--;
 696         *time = strtoul(tmp, NULL, 10);
 697
 698         *tmp = 0;
 699         while (*tmp != ' ')
 700                 tmp--;
 701         *mail = tmp + 1;
 702         *tmp = 0;
 703 }
 704
 705 static void get_commit_info(struct commit *commit, struct commit_info *ret, int detailed)
 706 {
 707         int len;
 708         char *tmp, *endp;
 709         static char author_buf[1024];
 710         static char committer_buf[1024];
 711         static char summary_buf[1024];
 712
 713         ret->author = author_buf;
 714         get_ac_line(commit->buffer, "\nauthor ",
 715                     sizeof(author_buf), author_buf, &ret->author_mail,
 716                     &ret->author_time, &ret->author_tz);
 717
 718         if (!detailed)
 719                 return;
 720
 721         ret->committer = committer_buf;
 722         get_ac_line(commit->buffer, "\ncommitter ",
 723                     sizeof(committer_buf), committer_buf, &ret->committer_mail,
 724                     &ret->committer_time, &ret->committer_tz);
 725
 726         ret->summary = summary_buf;
 727         tmp = strstr(commit->buffer, "\n\n");
 728         if (!tmp) {
 729         error_out:
 730                 sprintf(summary_buf, "(%s)", sha1_to_hex(commit->object.sha1));
 731                 return;
 732         }
 733         tmp += 2;
 734         endp = strchr(tmp, '\n');
 735         if (!endp)
 736                 goto error_out;
 737         len = endp - tmp;
 738         if (len >= sizeof(summary_buf))
 739                 goto error_out;
 740         memcpy(summary_buf, tmp, len);
 741         summary_buf[len] = 0;
 742 }
 743
 744 static const char *format_time(unsigned long time, const char *tz_str,
 745                                int show_raw_time)
 746 {
 747         static char time_buf[128];
 748         time_t t = time;
 749         int minutes, tz;
 750         struct tm *tm;
 751
 752         if (show_raw_time) {
 753                 sprintf(time_buf, "%lu %s", time, tz_str);
 754                 return time_buf;
 755         }
 756
 757         tz = atoi(tz_str);
 758         minutes = tz < 0 ? -tz : tz;
 759         minutes = (minutes / 100)*60 + (minutes % 100);
 760         minutes = tz < 0 ? -minutes : minutes;
 761         t = time + minutes * 60;
 762         tm = gmtime(&t);
 763
 764         strftime(time_buf, sizeof(time_buf), "%Y-%m-%d %H:%M:%S ", tm);
 765         strcat(time_buf, tz_str);
 766         return time_buf;
 767 }
 768
 769 static void topo_setter(struct commit *c, void *data)
 770 {
 771         struct util_info *util = c->util;
 772         util->topo_data = data;
 773 }
 774
 775 static void *topo_getter(struct commit *c)
 776 {
 777         struct util_info *util = c->util;
 778         return util->topo_data;
 779 }
 780
 781 static int read_ancestry(const char *graft_file,
 782                          unsigned char **start_sha1)
 783 {
 784         FILE *fp = fopen(graft_file, "r");
 785         char buf[1024];
 786         if (!fp)
 787                 return -1;
 788         while (fgets(buf, sizeof(buf), fp)) {
 789                 /* The format is just "Commit Parent1 Parent2 ...\n" */
 790                 int len = strlen(buf);
 791                 struct commit_graft *graft = read_graft_line(buf, len);
 792                 register_commit_graft(graft, 0);
 793                 if (!*start_sha1)
 794                         *start_sha1 = graft->sha1;
 795         }
 796         fclose(fp);
 797         return 0;
 798 }
 799
 800 static int lineno_width(int lines)
 801 {
 802         int i, width;
 803
 804         for (width = 1, i = 10; i <= lines + 1; width++)
 805                 i *= 10;
 806         return width;
 807 }
 808
 809 static int find_orig_linenum(struct util_info *u, int lineno)
 810 {
 811         int i;
 812
 813         for (i = 0; i < u->num_lines; i++)
 814                 if (lineno == u->line_map[i])
 815                         return i + 1;
 816         return 0;
 817 }
 818
 819 static void emit_meta(struct commit *c, int lno,
 820                       int sha1_len, int compatibility, int porcelain,
 821                       int show_name, int show_number, int show_raw_time,
 822                       int longest_file, int longest_author,
 823                       int max_digits, int max_orig_digits)
 824 {
 825         struct util_info *u;
 826         int lineno;
 827         struct commit_info ci;
 828
 829         u = c->util;
 830         lineno = find_orig_linenum(u, lno);
 831
 832         if (porcelain) {
 833                 int group_size = -1;
 834                 struct commit *cc = (lno == 0) ? NULL : blame_lines[lno-1];
 835                 if (cc != c) {
 836                         /* This is the beginning of this group */
 837                         int i;
 838                         for (i = lno + 1; i < num_blame_lines; i++)
 839                                 if (blame_lines[i] != c)
 840                                         break;
 841                         group_size = i - lno;
 842                 }
 843                 if (0 < group_size)
 844                         printf("%s %d %d %d\n", sha1_to_hex(c->object.sha1),
 845                                lineno, lno + 1, group_size);
 846                 else
 847                         printf("%s %d %d\n", sha1_to_hex(c->object.sha1),
 848                                lineno, lno + 1);
 849                 if (!u->meta_given) {
 850                         get_commit_info(c, &ci, 1);
 851                         printf("author %s\n", ci.author);
 852                         printf("author-mail %s\n", ci.author_mail);
 853                         printf("author-time %lu\n", ci.author_time);
 854                         printf("author-tz %s\n", ci.author_tz);
 855                         printf("committer %s\n", ci.committer);
 856                         printf("committer-mail %s\n", ci.committer_mail);
 857                         printf("committer-time %lu\n", ci.committer_time);
 858                         printf("committer-tz %s\n", ci.committer_tz);
 859                         printf("filename ");
 860                         if (quote_c_style(u->pathname, NULL, NULL, 0))
 861                                 quote_c_style(u->pathname, NULL, stdout, 0);
 862                         else
 863                                 fputs(u->pathname, stdout);
 864                         printf("\nsummary %s\n", ci.summary);
 865
 866                         u->meta_given = 1;
 867                 }
 868                 putchar('\t');
 869                 return;
 870         }
 871
 872         get_commit_info(c, &ci, 0);
 873         fwrite(sha1_to_hex(c->object.sha1), sha1_len, 1, stdout);
 874         if (compatibility) {
 875                 printf("\t(%10s\t%10s\t%d)", ci.author,
 876                        format_time(ci.author_time, ci.author_tz,
 877                                    show_raw_time),
 878                        lno + 1);
 879         }
 880         else {
 881                 if (show_name)
 882                         printf(" %-*.*s", longest_file, longest_file,
 883                                u->pathname);
 884                 if (show_number)
 885                         printf(" %*d", max_orig_digits,
 886                                lineno);
 887                 printf(" (%-*.*s %10s %*d) ",
 888                        longest_author, longest_author, ci.author,
 889                        format_time(ci.author_time, ci.author_tz,
 890                                    show_raw_time),
 891                        max_digits, lno + 1);
 892         }
 893 }
 894
 895 int main(int argc, const char **argv)
 896 {
 897         int i;
 898         struct commit *initial = NULL;
 899         unsigned char sha1[20], *sha1_p = NULL;
 900
 901         const char *filename = NULL, *commit = NULL;
 902         char filename_buf[256];
 903         int sha1_len = 8;
 904         int compatibility = 0;
 905         int show_raw_time = 0;
 906         int options = 1;
 907         struct commit *start_commit;
 908
 909         const char *args[10];
 910         struct rev_info rev;
 911
 912         struct commit_info ci;
 913         const char *buf;
 914         int max_digits, max_orig_digits;
 915         int longest_file, longest_author, longest_file_lines;
 916         int show_name = 0;
 917         int show_number = 0;
 918         int porcelain = 0;
 919
 920         const char *prefix = setup_git_directory();
 921         git_config(git_default_config);
 922
 923         for (i = 1; i < argc; i++) {
 924                 if (options) {
 925                         if (!strcmp(argv[i], "-h") ||
 926                            !strcmp(argv[i], "--help"))
 927                                 usage(blame_usage);
 928                         if (!strcmp(argv[i], "-l") ||
 929                             !strcmp(argv[i], "--long")) {
 930                                 sha1_len = 40;
 931                                 continue;
 932                         }
 933                         if (!strcmp(argv[i], "-c") ||
 934                             !strcmp(argv[i], "--compatibility")) {
 935                                 compatibility = 1;
 936                                 continue;
 937                         }
 938                         if (!strcmp(argv[i], "-t") ||
 939                             !strcmp(argv[i], "--time")) {
 940                                 show_raw_time = 1;
 941                                 continue;
 942                         }
 943                         if (!strcmp(argv[i], "-S")) {
 944                                 if (i + 1 < argc &&
 945                                     !read_ancestry(argv[i + 1], &sha1_p)) {
 946                                         compatibility = 1;
 947                                         i++;
 948                                         continue;
 949                                 }
 950                                 usage(blame_usage);
 951                         }
 952                         if (!strcmp(argv[i], "-f") ||
 953                             !strcmp(argv[i], "--show-name")) {
 954                                 show_name = 1;
 955                                 continue;
 956                         }
 957                         if (!strcmp(argv[i], "-n") ||
 958                             !strcmp(argv[i], "--show-number")) {
 959                                 show_number = 1;
 960                                 continue;
 961                         }
 962                         if (!strcmp(argv[i], "-p") ||
 963                             !strcmp(argv[i], "--porcelain")) {
 964                                 porcelain = 1;
 965                                 sha1_len = 40;
 966                                 show_raw_time = 1;
 967                                 continue;
 968                         }
 969                         if (!strcmp(argv[i], "--")) {
 970                                 options = 0;
 971                                 continue;
 972                         }
 973                         if (argv[i][0] == '-')
 974                                 usage(blame_usage);
 975                         options = 0;
 976                 }
 977
 978                 if (!options) {
 979                         if (!filename)
 980                                 filename = argv[i];
 981                         else if (!commit)
 982                                 commit = argv[i];
 983                         else
 984                                 usage(blame_usage);
 985                 }
 986         }
 987
 988         if (!filename)
 989                 usage(blame_usage);
 990         if (commit && sha1_p)
 991                 usage(blame_usage);
 992         else if (!commit)
 993                 commit = "HEAD";
 994
 995         if (prefix)
 996                 sprintf(filename_buf, "%s%s", prefix, filename);
 997         else
 998                 strcpy(filename_buf, filename);
 999         filename = filename_buf;
1000
1001         if (!sha1_p) {
1002                 if (get_sha1(commit, sha1))
1003                         die("get_sha1 failed, commit '%s' not found", commit);
1004                 sha1_p = sha1;
1005         }
1006         start_commit = lookup_commit_reference(sha1_p);
1007         get_util(start_commit)->pathname = filename;
1008         if (fill_util_info(start_commit)) {
1009                 printf("%s not found in %s\n", filename, commit);
1010                 return 1;
1011         }
1012
1013         init_revisions(&rev, setup_git_directory());
1014         rev.remove_empty_trees = 1;
1015         rev.topo_order = 1;
1016         rev.prune_fn = simplify_commit;
1017         rev.topo_setter = topo_setter;
1018         rev.topo_getter = topo_getter;
1019         rev.parents = 1;
1020         rev.limited = 1;
1021
1022         commit_list_insert(start_commit, &rev.commits);
1023
1024         args[0] = filename;
1025         args[1] = NULL;
1026         diff_tree_setup_paths(args, &rev.pruning);
1027         prepare_revision_walk(&rev);
1028         process_commits(&rev, filename, &initial);
1029
1030         for (i = 0; i < num_blame_lines; i++)
1031                 if (!blame_lines[i])
1032                         blame_lines[i] = initial;
1033
1034         buf = blame_contents;
1035         max_digits = lineno_width(num_blame_lines);
1036
1037         longest_file = 0;
1038         longest_author = 0;
1039         longest_file_lines = 0;
1040         for (i = 0; i < num_blame_lines; i++) {
1041                 struct commit *c = blame_lines[i];
1042                 struct util_info *u;
1043                 u = c->util;
1044
1045                 if (!show_name && strcmp(filename, u->pathname))
1046                         show_name = 1;
1047                 if (longest_file < strlen(u->pathname))
1048                         longest_file = strlen(u->pathname);
1049                 if (longest_file_lines < u->num_lines)
1050                         longest_file_lines = u->num_lines;
1051                 get_commit_info(c, &ci, 0);
1052                 if (longest_author < strlen(ci.author))
1053                         longest_author = strlen(ci.author);
1054         }
1055
1056         max_orig_digits = lineno_width(longest_file_lines);
1057
1058         for (i = 0; i < num_blame_lines; i++) {
1059                 emit_meta(blame_lines[i], i,
1060                           sha1_len, compatibility, porcelain,
1061                           show_name, show_number, show_raw_time,
1062                           longest_file, longest_author,
1063                           max_digits, max_orig_digits);
1064
1065                 if (i == num_blame_lines - 1) {
1066                         fwrite(buf, blame_len - (buf - blame_contents),
1067                                1, stdout);
1068                         if (blame_contents[blame_len-1] != '\n')
1069                                 putc('\n', stdout);
1070                 }
1071                 else {
1072                         char *next_buf = strchr(buf, '\n') + 1;
1073                         fwrite(buf, next_buf - buf, 1, stdout);
1074                         buf = next_buf;
1075                 }
1076         }
1077
1078         if (DEBUG) {
1079                 printf("num get patch: %d\n", num_get_patch);
1080                 printf("num commits: %d\n", num_commits);
1081                 printf("patch time: %f\n", patch_time / 1000000.0);
1082                 printf("initial: %s\n", sha1_to_hex(initial->object.sha1));
1083         }
1084
1085         return 0;
1086 }