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