Build-in merge-recursive
[git/dscho.git] / builtin-blame.c
blobc7e68874e7f02ac150343ab6d7a0aa95601f2ba3
1 /*
2  * Pickaxe
3  *
4  * Copyright (c) 2006, Junio C Hamano
5  */
7 #include "cache.h"
8 #include "builtin.h"
9 #include "blob.h"
10 #include "commit.h"
11 #include "tag.h"
12 #include "tree-walk.h"
13 #include "diff.h"
14 #include "diffcore.h"
15 #include "revision.h"
16 #include "quote.h"
17 #include "xdiff-interface.h"
18 #include "cache-tree.h"
19 #include "path-list.h"
20 #include "mailmap.h"
22 static char blame_usage[] =
23 "git-blame [-c] [-b] [-l] [--root] [-t] [-f] [-n] [-s] [-p] [-w] [-L n,m] [-S <revs-file>] [-M] [-C] [-C] [--contents <filename>] [--incremental] [commit] [--] file\n"
24 "  -c                  Use the same output mode as git-annotate (Default: off)\n"
25 "  -b                  Show blank SHA-1 for boundary commits (Default: off)\n"
26 "  -l                  Show long commit SHA1 (Default: off)\n"
27 "  --root              Do not treat root commits as boundaries (Default: off)\n"
28 "  -t                  Show raw timestamp (Default: off)\n"
29 "  -f, --show-name     Show original filename (Default: auto)\n"
30 "  -n, --show-number   Show original linenumber (Default: off)\n"
31 "  -s                  Suppress author name and timestamp (Default: off)\n"
32 "  -p, --porcelain     Show in a format designed for machine consumption\n"
33 "  -w                  Ignore whitespace differences\n"
34 "  -L n,m              Process only line range n,m, counting from 1\n"
35 "  -M, -C              Find line movements within and across files\n"
36 "  --incremental       Show blame entries as we find them, incrementally\n"
37 "  --contents file     Use <file>'s contents as the final image\n"
38 "  -S revs-file        Use revisions from revs-file instead of calling git-rev-list\n";
40 static int longest_file;
41 static int longest_author;
42 static int max_orig_digits;
43 static int max_digits;
44 static int max_score_digits;
45 static int show_root;
46 static int blank_boundary;
47 static int incremental;
48 static int cmd_is_annotate;
49 static int xdl_opts = XDF_NEED_MINIMAL;
50 static struct path_list mailmap;
52 #ifndef DEBUG
53 #define DEBUG 0
54 #endif
56 /* stats */
57 static int num_read_blob;
58 static int num_get_patch;
59 static int num_commits;
61 #define PICKAXE_BLAME_MOVE              01
62 #define PICKAXE_BLAME_COPY              02
63 #define PICKAXE_BLAME_COPY_HARDER       04
64 #define PICKAXE_BLAME_COPY_HARDEST      010
67  * blame for a blame_entry with score lower than these thresholds
68  * is not passed to the parent using move/copy logic.
69  */
70 static unsigned blame_move_score;
71 static unsigned blame_copy_score;
72 #define BLAME_DEFAULT_MOVE_SCORE        20
73 #define BLAME_DEFAULT_COPY_SCORE        40
75 /* bits #0..7 in revision.h, #8..11 used for merge_bases() in commit.c */
76 #define METAINFO_SHOWN          (1u<<12)
77 #define MORE_THAN_ONE_PATH      (1u<<13)
80  * One blob in a commit that is being suspected
81  */
82 struct origin {
83         int refcnt;
84         struct commit *commit;
85         mmfile_t file;
86         unsigned char blob_sha1[20];
87         char path[FLEX_ARRAY];
91  * Given an origin, prepare mmfile_t structure to be used by the
92  * diff machinery
93  */
94 static char *fill_origin_blob(struct origin *o, mmfile_t *file)
96         if (!o->file.ptr) {
97                 enum object_type type;
98                 num_read_blob++;
99                 file->ptr = read_sha1_file(o->blob_sha1, &type,
100                                            (unsigned long *)(&(file->size)));
101                 if (!file->ptr)
102                         die("Cannot read blob %s for path %s",
103                             sha1_to_hex(o->blob_sha1),
104                             o->path);
105                 o->file = *file;
106         }
107         else
108                 *file = o->file;
109         return file->ptr;
113  * Origin is refcounted and usually we keep the blob contents to be
114  * reused.
115  */
116 static inline struct origin *origin_incref(struct origin *o)
118         if (o)
119                 o->refcnt++;
120         return o;
123 static void origin_decref(struct origin *o)
125         if (o && --o->refcnt <= 0) {
126                 if (o->file.ptr)
127                         free(o->file.ptr);
128                 free(o);
129         }
132 static void drop_origin_blob(struct origin *o)
134         if (o->file.ptr) {
135                 free(o->file.ptr);
136                 o->file.ptr = NULL;
137         }
141  * Each group of lines is described by a blame_entry; it can be split
142  * as we pass blame to the parents.  They form a linked list in the
143  * scoreboard structure, sorted by the target line number.
144  */
145 struct blame_entry {
146         struct blame_entry *prev;
147         struct blame_entry *next;
149         /* the first line of this group in the final image;
150          * internally all line numbers are 0 based.
151          */
152         int lno;
154         /* how many lines this group has */
155         int num_lines;
157         /* the commit that introduced this group into the final image */
158         struct origin *suspect;
160         /* true if the suspect is truly guilty; false while we have not
161          * checked if the group came from one of its parents.
162          */
163         char guilty;
165         /* the line number of the first line of this group in the
166          * suspect's file; internally all line numbers are 0 based.
167          */
168         int s_lno;
170         /* how significant this entry is -- cached to avoid
171          * scanning the lines over and over.
172          */
173         unsigned score;
177  * The current state of the blame assignment.
178  */
179 struct scoreboard {
180         /* the final commit (i.e. where we started digging from) */
181         struct commit *final;
183         const char *path;
185         /*
186          * The contents in the final image.
187          * Used by many functions to obtain contents of the nth line,
188          * indexed with scoreboard.lineno[blame_entry.lno].
189          */
190         const char *final_buf;
191         unsigned long final_buf_size;
193         /* linked list of blames */
194         struct blame_entry *ent;
196         /* look-up a line in the final buffer */
197         int num_lines;
198         int *lineno;
201 static inline int same_suspect(struct origin *a, struct origin *b)
203         if (a == b)
204                 return 1;
205         if (a->commit != b->commit)
206                 return 0;
207         return !strcmp(a->path, b->path);
210 static void sanity_check_refcnt(struct scoreboard *);
213  * If two blame entries that are next to each other came from
214  * contiguous lines in the same origin (i.e. <commit, path> pair),
215  * merge them together.
216  */
217 static void coalesce(struct scoreboard *sb)
219         struct blame_entry *ent, *next;
221         for (ent = sb->ent; ent && (next = ent->next); ent = next) {
222                 if (same_suspect(ent->suspect, next->suspect) &&
223                     ent->guilty == next->guilty &&
224                     ent->s_lno + ent->num_lines == next->s_lno) {
225                         ent->num_lines += next->num_lines;
226                         ent->next = next->next;
227                         if (ent->next)
228                                 ent->next->prev = ent;
229                         origin_decref(next->suspect);
230                         free(next);
231                         ent->score = 0;
232                         next = ent; /* again */
233                 }
234         }
236         if (DEBUG) /* sanity */
237                 sanity_check_refcnt(sb);
241  * Given a commit and a path in it, create a new origin structure.
242  * The callers that add blame to the scoreboard should use
243  * get_origin() to obtain shared, refcounted copy instead of calling
244  * this function directly.
245  */
246 static struct origin *make_origin(struct commit *commit, const char *path)
248         struct origin *o;
249         o = xcalloc(1, sizeof(*o) + strlen(path) + 1);
250         o->commit = commit;
251         o->refcnt = 1;
252         strcpy(o->path, path);
253         return o;
257  * Locate an existing origin or create a new one.
258  */
259 static struct origin *get_origin(struct scoreboard *sb,
260                                  struct commit *commit,
261                                  const char *path)
263         struct blame_entry *e;
265         for (e = sb->ent; e; e = e->next) {
266                 if (e->suspect->commit == commit &&
267                     !strcmp(e->suspect->path, path))
268                         return origin_incref(e->suspect);
269         }
270         return make_origin(commit, path);
274  * Fill the blob_sha1 field of an origin if it hasn't, so that later
275  * call to fill_origin_blob() can use it to locate the data.  blob_sha1
276  * for an origin is also used to pass the blame for the entire file to
277  * the parent to detect the case where a child's blob is identical to
278  * that of its parent's.
279  */
280 static int fill_blob_sha1(struct origin *origin)
282         unsigned mode;
284         if (!is_null_sha1(origin->blob_sha1))
285                 return 0;
286         if (get_tree_entry(origin->commit->object.sha1,
287                            origin->path,
288                            origin->blob_sha1, &mode))
289                 goto error_out;
290         if (sha1_object_info(origin->blob_sha1, NULL) != OBJ_BLOB)
291                 goto error_out;
292         return 0;
293  error_out:
294         hashclr(origin->blob_sha1);
295         return -1;
299  * We have an origin -- check if the same path exists in the
300  * parent and return an origin structure to represent it.
301  */
302 static struct origin *find_origin(struct scoreboard *sb,
303                                   struct commit *parent,
304                                   struct origin *origin)
306         struct origin *porigin = NULL;
307         struct diff_options diff_opts;
308         const char *paths[2];
310         if (parent->util) {
311                 /*
312                  * Each commit object can cache one origin in that
313                  * commit.  This is a freestanding copy of origin and
314                  * not refcounted.
315                  */
316                 struct origin *cached = parent->util;
317                 if (!strcmp(cached->path, origin->path)) {
318                         /*
319                          * The same path between origin and its parent
320                          * without renaming -- the most common case.
321                          */
322                         porigin = get_origin(sb, parent, cached->path);
324                         /*
325                          * If the origin was newly created (i.e. get_origin
326                          * would call make_origin if none is found in the
327                          * scoreboard), it does not know the blob_sha1,
328                          * so copy it.  Otherwise porigin was in the
329                          * scoreboard and already knows blob_sha1.
330                          */
331                         if (porigin->refcnt == 1)
332                                 hashcpy(porigin->blob_sha1, cached->blob_sha1);
333                         return porigin;
334                 }
335                 /* otherwise it was not very useful; free it */
336                 free(parent->util);
337                 parent->util = NULL;
338         }
340         /* See if the origin->path is different between parent
341          * and origin first.  Most of the time they are the
342          * same and diff-tree is fairly efficient about this.
343          */
344         diff_setup(&diff_opts);
345         DIFF_OPT_SET(&diff_opts, RECURSIVE);
346         diff_opts.detect_rename = 0;
347         diff_opts.output_format = DIFF_FORMAT_NO_OUTPUT;
348         paths[0] = origin->path;
349         paths[1] = NULL;
351         diff_tree_setup_paths(paths, &diff_opts);
352         if (diff_setup_done(&diff_opts) < 0)
353                 die("diff-setup");
355         if (is_null_sha1(origin->commit->object.sha1))
356                 do_diff_cache(parent->tree->object.sha1, &diff_opts);
357         else
358                 diff_tree_sha1(parent->tree->object.sha1,
359                                origin->commit->tree->object.sha1,
360                                "", &diff_opts);
361         diffcore_std(&diff_opts);
363         /* It is either one entry that says "modified", or "created",
364          * or nothing.
365          */
366         if (!diff_queued_diff.nr) {
367                 /* The path is the same as parent */
368                 porigin = get_origin(sb, parent, origin->path);
369                 hashcpy(porigin->blob_sha1, origin->blob_sha1);
370         }
371         else if (diff_queued_diff.nr != 1)
372                 die("internal error in blame::find_origin");
373         else {
374                 struct diff_filepair *p = diff_queued_diff.queue[0];
375                 switch (p->status) {
376                 default:
377                         die("internal error in blame::find_origin (%c)",
378                             p->status);
379                 case 'M':
380                         porigin = get_origin(sb, parent, origin->path);
381                         hashcpy(porigin->blob_sha1, p->one->sha1);
382                         break;
383                 case 'A':
384                 case 'T':
385                         /* Did not exist in parent, or type changed */
386                         break;
387                 }
388         }
389         diff_flush(&diff_opts);
390         diff_tree_release_paths(&diff_opts);
391         if (porigin) {
392                 /*
393                  * Create a freestanding copy that is not part of
394                  * the refcounted origin found in the scoreboard, and
395                  * cache it in the commit.
396                  */
397                 struct origin *cached;
399                 cached = make_origin(porigin->commit, porigin->path);
400                 hashcpy(cached->blob_sha1, porigin->blob_sha1);
401                 parent->util = cached;
402         }
403         return porigin;
407  * We have an origin -- find the path that corresponds to it in its
408  * parent and return an origin structure to represent it.
409  */
410 static struct origin *find_rename(struct scoreboard *sb,
411                                   struct commit *parent,
412                                   struct origin *origin)
414         struct origin *porigin = NULL;
415         struct diff_options diff_opts;
416         int i;
417         const char *paths[2];
419         diff_setup(&diff_opts);
420         DIFF_OPT_SET(&diff_opts, RECURSIVE);
421         diff_opts.detect_rename = DIFF_DETECT_RENAME;
422         diff_opts.output_format = DIFF_FORMAT_NO_OUTPUT;
423         diff_opts.single_follow = origin->path;
424         paths[0] = NULL;
425         diff_tree_setup_paths(paths, &diff_opts);
426         if (diff_setup_done(&diff_opts) < 0)
427                 die("diff-setup");
429         if (is_null_sha1(origin->commit->object.sha1))
430                 do_diff_cache(parent->tree->object.sha1, &diff_opts);
431         else
432                 diff_tree_sha1(parent->tree->object.sha1,
433                                origin->commit->tree->object.sha1,
434                                "", &diff_opts);
435         diffcore_std(&diff_opts);
437         for (i = 0; i < diff_queued_diff.nr; i++) {
438                 struct diff_filepair *p = diff_queued_diff.queue[i];
439                 if ((p->status == 'R' || p->status == 'C') &&
440                     !strcmp(p->two->path, origin->path)) {
441                         porigin = get_origin(sb, parent, p->one->path);
442                         hashcpy(porigin->blob_sha1, p->one->sha1);
443                         break;
444                 }
445         }
446         diff_flush(&diff_opts);
447         diff_tree_release_paths(&diff_opts);
448         return porigin;
452  * Parsing of patch chunks...
453  */
454 struct chunk {
455         /* line number in postimage; up to but not including this
456          * line is the same as preimage
457          */
458         int same;
460         /* preimage line number after this chunk */
461         int p_next;
463         /* postimage line number after this chunk */
464         int t_next;
467 struct patch {
468         struct chunk *chunks;
469         int num;
472 struct blame_diff_state {
473         struct xdiff_emit_state xm;
474         struct patch *ret;
475         unsigned hunk_post_context;
476         unsigned hunk_in_pre_context : 1;
479 static void process_u_diff(void *state_, char *line, unsigned long len)
481         struct blame_diff_state *state = state_;
482         struct chunk *chunk;
483         int off1, off2, len1, len2, num;
485         num = state->ret->num;
486         if (len < 4 || line[0] != '@' || line[1] != '@') {
487                 if (state->hunk_in_pre_context && line[0] == ' ')
488                         state->ret->chunks[num - 1].same++;
489                 else {
490                         state->hunk_in_pre_context = 0;
491                         if (line[0] == ' ')
492                                 state->hunk_post_context++;
493                         else
494                                 state->hunk_post_context = 0;
495                 }
496                 return;
497         }
499         if (num && state->hunk_post_context) {
500                 chunk = &state->ret->chunks[num - 1];
501                 chunk->p_next -= state->hunk_post_context;
502                 chunk->t_next -= state->hunk_post_context;
503         }
504         state->ret->num = ++num;
505         state->ret->chunks = xrealloc(state->ret->chunks,
506                                       sizeof(struct chunk) * num);
507         chunk = &state->ret->chunks[num - 1];
508         if (parse_hunk_header(line, len, &off1, &len1, &off2, &len2)) {
509                 state->ret->num--;
510                 return;
511         }
513         /* Line numbers in patch output are one based. */
514         off1--;
515         off2--;
517         chunk->same = len2 ? off2 : (off2 + 1);
519         chunk->p_next = off1 + (len1 ? len1 : 1);
520         chunk->t_next = chunk->same + len2;
521         state->hunk_in_pre_context = 1;
522         state->hunk_post_context = 0;
525 static struct patch *compare_buffer(mmfile_t *file_p, mmfile_t *file_o,
526                                     int context)
528         struct blame_diff_state state;
529         xpparam_t xpp;
530         xdemitconf_t xecfg;
531         xdemitcb_t ecb;
533         xpp.flags = xdl_opts;
534         memset(&xecfg, 0, sizeof(xecfg));
535         xecfg.ctxlen = context;
536         ecb.outf = xdiff_outf;
537         ecb.priv = &state;
538         memset(&state, 0, sizeof(state));
539         state.xm.consume = process_u_diff;
540         state.ret = xmalloc(sizeof(struct patch));
541         state.ret->chunks = NULL;
542         state.ret->num = 0;
544         xdi_diff(file_p, file_o, &xpp, &xecfg, &ecb);
546         if (state.ret->num) {
547                 struct chunk *chunk;
548                 chunk = &state.ret->chunks[state.ret->num - 1];
549                 chunk->p_next -= state.hunk_post_context;
550                 chunk->t_next -= state.hunk_post_context;
551         }
552         return state.ret;
556  * Run diff between two origins and grab the patch output, so that
557  * we can pass blame for lines origin is currently suspected for
558  * to its parent.
559  */
560 static struct patch *get_patch(struct origin *parent, struct origin *origin)
562         mmfile_t file_p, file_o;
563         struct patch *patch;
565         fill_origin_blob(parent, &file_p);
566         fill_origin_blob(origin, &file_o);
567         if (!file_p.ptr || !file_o.ptr)
568                 return NULL;
569         patch = compare_buffer(&file_p, &file_o, 0);
570         num_get_patch++;
571         return patch;
574 static void free_patch(struct patch *p)
576         free(p->chunks);
577         free(p);
581  * Link in a new blame entry to the scoreboard.  Entries that cover the
582  * same line range have been removed from the scoreboard previously.
583  */
584 static void add_blame_entry(struct scoreboard *sb, struct blame_entry *e)
586         struct blame_entry *ent, *prev = NULL;
588         origin_incref(e->suspect);
590         for (ent = sb->ent; ent && ent->lno < e->lno; ent = ent->next)
591                 prev = ent;
593         /* prev, if not NULL, is the last one that is below e */
594         e->prev = prev;
595         if (prev) {
596                 e->next = prev->next;
597                 prev->next = e;
598         }
599         else {
600                 e->next = sb->ent;
601                 sb->ent = e;
602         }
603         if (e->next)
604                 e->next->prev = e;
608  * src typically is on-stack; we want to copy the information in it to
609  * a malloced blame_entry that is already on the linked list of the
610  * scoreboard.  The origin of dst loses a refcnt while the origin of src
611  * gains one.
612  */
613 static void dup_entry(struct blame_entry *dst, struct blame_entry *src)
615         struct blame_entry *p, *n;
617         p = dst->prev;
618         n = dst->next;
619         origin_incref(src->suspect);
620         origin_decref(dst->suspect);
621         memcpy(dst, src, sizeof(*src));
622         dst->prev = p;
623         dst->next = n;
624         dst->score = 0;
627 static const char *nth_line(struct scoreboard *sb, int lno)
629         return sb->final_buf + sb->lineno[lno];
633  * It is known that lines between tlno to same came from parent, and e
634  * has an overlap with that range.  it also is known that parent's
635  * line plno corresponds to e's line tlno.
637  *                <---- e ----->
638  *                   <------>
639  *                   <------------>
640  *             <------------>
641  *             <------------------>
643  * Split e into potentially three parts; before this chunk, the chunk
644  * to be blamed for the parent, and after that portion.
645  */
646 static void split_overlap(struct blame_entry *split,
647                           struct blame_entry *e,
648                           int tlno, int plno, int same,
649                           struct origin *parent)
651         int chunk_end_lno;
652         memset(split, 0, sizeof(struct blame_entry [3]));
654         if (e->s_lno < tlno) {
655                 /* there is a pre-chunk part not blamed on parent */
656                 split[0].suspect = origin_incref(e->suspect);
657                 split[0].lno = e->lno;
658                 split[0].s_lno = e->s_lno;
659                 split[0].num_lines = tlno - e->s_lno;
660                 split[1].lno = e->lno + tlno - e->s_lno;
661                 split[1].s_lno = plno;
662         }
663         else {
664                 split[1].lno = e->lno;
665                 split[1].s_lno = plno + (e->s_lno - tlno);
666         }
668         if (same < e->s_lno + e->num_lines) {
669                 /* there is a post-chunk part not blamed on parent */
670                 split[2].suspect = origin_incref(e->suspect);
671                 split[2].lno = e->lno + (same - e->s_lno);
672                 split[2].s_lno = e->s_lno + (same - e->s_lno);
673                 split[2].num_lines = e->s_lno + e->num_lines - same;
674                 chunk_end_lno = split[2].lno;
675         }
676         else
677                 chunk_end_lno = e->lno + e->num_lines;
678         split[1].num_lines = chunk_end_lno - split[1].lno;
680         /*
681          * if it turns out there is nothing to blame the parent for,
682          * forget about the splitting.  !split[1].suspect signals this.
683          */
684         if (split[1].num_lines < 1)
685                 return;
686         split[1].suspect = origin_incref(parent);
690  * split_overlap() divided an existing blame e into up to three parts
691  * in split.  Adjust the linked list of blames in the scoreboard to
692  * reflect the split.
693  */
694 static void split_blame(struct scoreboard *sb,
695                         struct blame_entry *split,
696                         struct blame_entry *e)
698         struct blame_entry *new_entry;
700         if (split[0].suspect && split[2].suspect) {
701                 /* The first part (reuse storage for the existing entry e) */
702                 dup_entry(e, &split[0]);
704                 /* The last part -- me */
705                 new_entry = xmalloc(sizeof(*new_entry));
706                 memcpy(new_entry, &(split[2]), sizeof(struct blame_entry));
707                 add_blame_entry(sb, new_entry);
709                 /* ... and the middle part -- parent */
710                 new_entry = xmalloc(sizeof(*new_entry));
711                 memcpy(new_entry, &(split[1]), sizeof(struct blame_entry));
712                 add_blame_entry(sb, new_entry);
713         }
714         else if (!split[0].suspect && !split[2].suspect)
715                 /*
716                  * The parent covers the entire area; reuse storage for
717                  * e and replace it with the parent.
718                  */
719                 dup_entry(e, &split[1]);
720         else if (split[0].suspect) {
721                 /* me and then parent */
722                 dup_entry(e, &split[0]);
724                 new_entry = xmalloc(sizeof(*new_entry));
725                 memcpy(new_entry, &(split[1]), sizeof(struct blame_entry));
726                 add_blame_entry(sb, new_entry);
727         }
728         else {
729                 /* parent and then me */
730                 dup_entry(e, &split[1]);
732                 new_entry = xmalloc(sizeof(*new_entry));
733                 memcpy(new_entry, &(split[2]), sizeof(struct blame_entry));
734                 add_blame_entry(sb, new_entry);
735         }
737         if (DEBUG) { /* sanity */
738                 struct blame_entry *ent;
739                 int lno = sb->ent->lno, corrupt = 0;
741                 for (ent = sb->ent; ent; ent = ent->next) {
742                         if (lno != ent->lno)
743                                 corrupt = 1;
744                         if (ent->s_lno < 0)
745                                 corrupt = 1;
746                         lno += ent->num_lines;
747                 }
748                 if (corrupt) {
749                         lno = sb->ent->lno;
750                         for (ent = sb->ent; ent; ent = ent->next) {
751                                 printf("L %8d l %8d n %8d\n",
752                                        lno, ent->lno, ent->num_lines);
753                                 lno = ent->lno + ent->num_lines;
754                         }
755                         die("oops");
756                 }
757         }
761  * After splitting the blame, the origins used by the
762  * on-stack blame_entry should lose one refcnt each.
763  */
764 static void decref_split(struct blame_entry *split)
766         int i;
768         for (i = 0; i < 3; i++)
769                 origin_decref(split[i].suspect);
773  * Helper for blame_chunk().  blame_entry e is known to overlap with
774  * the patch hunk; split it and pass blame to the parent.
775  */
776 static void blame_overlap(struct scoreboard *sb, struct blame_entry *e,
777                           int tlno, int plno, int same,
778                           struct origin *parent)
780         struct blame_entry split[3];
782         split_overlap(split, e, tlno, plno, same, parent);
783         if (split[1].suspect)
784                 split_blame(sb, split, e);
785         decref_split(split);
789  * Find the line number of the last line the target is suspected for.
790  */
791 static int find_last_in_target(struct scoreboard *sb, struct origin *target)
793         struct blame_entry *e;
794         int last_in_target = -1;
796         for (e = sb->ent; e; e = e->next) {
797                 if (e->guilty || !same_suspect(e->suspect, target))
798                         continue;
799                 if (last_in_target < e->s_lno + e->num_lines)
800                         last_in_target = e->s_lno + e->num_lines;
801         }
802         return last_in_target;
806  * Process one hunk from the patch between the current suspect for
807  * blame_entry e and its parent.  Find and split the overlap, and
808  * pass blame to the overlapping part to the parent.
809  */
810 static void blame_chunk(struct scoreboard *sb,
811                         int tlno, int plno, int same,
812                         struct origin *target, struct origin *parent)
814         struct blame_entry *e;
816         for (e = sb->ent; e; e = e->next) {
817                 if (e->guilty || !same_suspect(e->suspect, target))
818                         continue;
819                 if (same <= e->s_lno)
820                         continue;
821                 if (tlno < e->s_lno + e->num_lines)
822                         blame_overlap(sb, e, tlno, plno, same, parent);
823         }
827  * We are looking at the origin 'target' and aiming to pass blame
828  * for the lines it is suspected to its parent.  Run diff to find
829  * which lines came from parent and pass blame for them.
830  */
831 static int pass_blame_to_parent(struct scoreboard *sb,
832                                 struct origin *target,
833                                 struct origin *parent)
835         int i, last_in_target, plno, tlno;
836         struct patch *patch;
838         last_in_target = find_last_in_target(sb, target);
839         if (last_in_target < 0)
840                 return 1; /* nothing remains for this target */
842         patch = get_patch(parent, target);
843         plno = tlno = 0;
844         for (i = 0; i < patch->num; i++) {
845                 struct chunk *chunk = &patch->chunks[i];
847                 blame_chunk(sb, tlno, plno, chunk->same, target, parent);
848                 plno = chunk->p_next;
849                 tlno = chunk->t_next;
850         }
851         /* The rest (i.e. anything after tlno) are the same as the parent */
852         blame_chunk(sb, tlno, plno, last_in_target, target, parent);
854         free_patch(patch);
855         return 0;
859  * The lines in blame_entry after splitting blames many times can become
860  * very small and trivial, and at some point it becomes pointless to
861  * blame the parents.  E.g. "\t\t}\n\t}\n\n" appears everywhere in any
862  * ordinary C program, and it is not worth to say it was copied from
863  * totally unrelated file in the parent.
865  * Compute how trivial the lines in the blame_entry are.
866  */
867 static unsigned ent_score(struct scoreboard *sb, struct blame_entry *e)
869         unsigned score;
870         const char *cp, *ep;
872         if (e->score)
873                 return e->score;
875         score = 1;
876         cp = nth_line(sb, e->lno);
877         ep = nth_line(sb, e->lno + e->num_lines);
878         while (cp < ep) {
879                 unsigned ch = *((unsigned char *)cp);
880                 if (isalnum(ch))
881                         score++;
882                 cp++;
883         }
884         e->score = score;
885         return score;
889  * best_so_far[] and this[] are both a split of an existing blame_entry
890  * that passes blame to the parent.  Maintain best_so_far the best split
891  * so far, by comparing this and best_so_far and copying this into
892  * bst_so_far as needed.
893  */
894 static void copy_split_if_better(struct scoreboard *sb,
895                                  struct blame_entry *best_so_far,
896                                  struct blame_entry *this)
898         int i;
900         if (!this[1].suspect)
901                 return;
902         if (best_so_far[1].suspect) {
903                 if (ent_score(sb, &this[1]) < ent_score(sb, &best_so_far[1]))
904                         return;
905         }
907         for (i = 0; i < 3; i++)
908                 origin_incref(this[i].suspect);
909         decref_split(best_so_far);
910         memcpy(best_so_far, this, sizeof(struct blame_entry [3]));
914  * We are looking at a part of the final image represented by
915  * ent (tlno and same are offset by ent->s_lno).
916  * tlno is where we are looking at in the final image.
917  * up to (but not including) same match preimage.
918  * plno is where we are looking at in the preimage.
920  * <-------------- final image ---------------------->
921  *       <------ent------>
922  *         ^tlno ^same
923  *    <---------preimage----->
924  *         ^plno
926  * All line numbers are 0-based.
927  */
928 static void handle_split(struct scoreboard *sb,
929                          struct blame_entry *ent,
930                          int tlno, int plno, int same,
931                          struct origin *parent,
932                          struct blame_entry *split)
934         if (ent->num_lines <= tlno)
935                 return;
936         if (tlno < same) {
937                 struct blame_entry this[3];
938                 tlno += ent->s_lno;
939                 same += ent->s_lno;
940                 split_overlap(this, ent, tlno, plno, same, parent);
941                 copy_split_if_better(sb, split, this);
942                 decref_split(this);
943         }
947  * Find the lines from parent that are the same as ent so that
948  * we can pass blames to it.  file_p has the blob contents for
949  * the parent.
950  */
951 static void find_copy_in_blob(struct scoreboard *sb,
952                               struct blame_entry *ent,
953                               struct origin *parent,
954                               struct blame_entry *split,
955                               mmfile_t *file_p)
957         const char *cp;
958         int cnt;
959         mmfile_t file_o;
960         struct patch *patch;
961         int i, plno, tlno;
963         /*
964          * Prepare mmfile that contains only the lines in ent.
965          */
966         cp = nth_line(sb, ent->lno);
967         file_o.ptr = (char*) cp;
968         cnt = ent->num_lines;
970         while (cnt && cp < sb->final_buf + sb->final_buf_size) {
971                 if (*cp++ == '\n')
972                         cnt--;
973         }
974         file_o.size = cp - file_o.ptr;
976         patch = compare_buffer(file_p, &file_o, 1);
978         /*
979          * file_o is a part of final image we are annotating.
980          * file_p partially may match that image.
981          */
982         memset(split, 0, sizeof(struct blame_entry [3]));
983         plno = tlno = 0;
984         for (i = 0; i < patch->num; i++) {
985                 struct chunk *chunk = &patch->chunks[i];
987                 handle_split(sb, ent, tlno, plno, chunk->same, parent, split);
988                 plno = chunk->p_next;
989                 tlno = chunk->t_next;
990         }
991         /* remainder, if any, all match the preimage */
992         handle_split(sb, ent, tlno, plno, ent->num_lines, parent, split);
993         free_patch(patch);
997  * See if lines currently target is suspected for can be attributed to
998  * parent.
999  */
1000 static int find_move_in_parent(struct scoreboard *sb,
1001                                struct origin *target,
1002                                struct origin *parent)
1004         int last_in_target, made_progress;
1005         struct blame_entry *e, split[3];
1006         mmfile_t file_p;
1008         last_in_target = find_last_in_target(sb, target);
1009         if (last_in_target < 0)
1010                 return 1; /* nothing remains for this target */
1012         fill_origin_blob(parent, &file_p);
1013         if (!file_p.ptr)
1014                 return 0;
1016         made_progress = 1;
1017         while (made_progress) {
1018                 made_progress = 0;
1019                 for (e = sb->ent; e; e = e->next) {
1020                         if (e->guilty || !same_suspect(e->suspect, target))
1021                                 continue;
1022                         find_copy_in_blob(sb, e, parent, split, &file_p);
1023                         if (split[1].suspect &&
1024                             blame_move_score < ent_score(sb, &split[1])) {
1025                                 split_blame(sb, split, e);
1026                                 made_progress = 1;
1027                         }
1028                         decref_split(split);
1029                 }
1030         }
1031         return 0;
1034 struct blame_list {
1035         struct blame_entry *ent;
1036         struct blame_entry split[3];
1040  * Count the number of entries the target is suspected for,
1041  * and prepare a list of entry and the best split.
1042  */
1043 static struct blame_list *setup_blame_list(struct scoreboard *sb,
1044                                            struct origin *target,
1045                                            int *num_ents_p)
1047         struct blame_entry *e;
1048         int num_ents, i;
1049         struct blame_list *blame_list = NULL;
1051         for (e = sb->ent, num_ents = 0; e; e = e->next)
1052                 if (!e->guilty && same_suspect(e->suspect, target))
1053                         num_ents++;
1054         if (num_ents) {
1055                 blame_list = xcalloc(num_ents, sizeof(struct blame_list));
1056                 for (e = sb->ent, i = 0; e; e = e->next)
1057                         if (!e->guilty && same_suspect(e->suspect, target))
1058                                 blame_list[i++].ent = e;
1059         }
1060         *num_ents_p = num_ents;
1061         return blame_list;
1065  * For lines target is suspected for, see if we can find code movement
1066  * across file boundary from the parent commit.  porigin is the path
1067  * in the parent we already tried.
1068  */
1069 static int find_copy_in_parent(struct scoreboard *sb,
1070                                struct origin *target,
1071                                struct commit *parent,
1072                                struct origin *porigin,
1073                                int opt)
1075         struct diff_options diff_opts;
1076         const char *paths[1];
1077         int i, j;
1078         int retval;
1079         struct blame_list *blame_list;
1080         int num_ents;
1082         blame_list = setup_blame_list(sb, target, &num_ents);
1083         if (!blame_list)
1084                 return 1; /* nothing remains for this target */
1086         diff_setup(&diff_opts);
1087         DIFF_OPT_SET(&diff_opts, RECURSIVE);
1088         diff_opts.output_format = DIFF_FORMAT_NO_OUTPUT;
1090         paths[0] = NULL;
1091         diff_tree_setup_paths(paths, &diff_opts);
1092         if (diff_setup_done(&diff_opts) < 0)
1093                 die("diff-setup");
1095         /* Try "find copies harder" on new path if requested;
1096          * we do not want to use diffcore_rename() actually to
1097          * match things up; find_copies_harder is set only to
1098          * force diff_tree_sha1() to feed all filepairs to diff_queue,
1099          * and this code needs to be after diff_setup_done(), which
1100          * usually makes find-copies-harder imply copy detection.
1101          */
1102         if ((opt & PICKAXE_BLAME_COPY_HARDEST)
1103             || ((opt & PICKAXE_BLAME_COPY_HARDER)
1104                 && (!porigin || strcmp(target->path, porigin->path))))
1105                 DIFF_OPT_SET(&diff_opts, FIND_COPIES_HARDER);
1107         if (is_null_sha1(target->commit->object.sha1))
1108                 do_diff_cache(parent->tree->object.sha1, &diff_opts);
1109         else
1110                 diff_tree_sha1(parent->tree->object.sha1,
1111                                target->commit->tree->object.sha1,
1112                                "", &diff_opts);
1114         if (!DIFF_OPT_TST(&diff_opts, FIND_COPIES_HARDER))
1115                 diffcore_std(&diff_opts);
1117         retval = 0;
1118         while (1) {
1119                 int made_progress = 0;
1121                 for (i = 0; i < diff_queued_diff.nr; i++) {
1122                         struct diff_filepair *p = diff_queued_diff.queue[i];
1123                         struct origin *norigin;
1124                         mmfile_t file_p;
1125                         struct blame_entry this[3];
1127                         if (!DIFF_FILE_VALID(p->one))
1128                                 continue; /* does not exist in parent */
1129                         if (porigin && !strcmp(p->one->path, porigin->path))
1130                                 /* find_move already dealt with this path */
1131                                 continue;
1133                         norigin = get_origin(sb, parent, p->one->path);
1134                         hashcpy(norigin->blob_sha1, p->one->sha1);
1135                         fill_origin_blob(norigin, &file_p);
1136                         if (!file_p.ptr)
1137                                 continue;
1139                         for (j = 0; j < num_ents; j++) {
1140                                 find_copy_in_blob(sb, blame_list[j].ent,
1141                                                   norigin, this, &file_p);
1142                                 copy_split_if_better(sb, blame_list[j].split,
1143                                                      this);
1144                                 decref_split(this);
1145                         }
1146                         origin_decref(norigin);
1147                 }
1149                 for (j = 0; j < num_ents; j++) {
1150                         struct blame_entry *split = blame_list[j].split;
1151                         if (split[1].suspect &&
1152                             blame_copy_score < ent_score(sb, &split[1])) {
1153                                 split_blame(sb, split, blame_list[j].ent);
1154                                 made_progress = 1;
1155                         }
1156                         decref_split(split);
1157                 }
1158                 free(blame_list);
1160                 if (!made_progress)
1161                         break;
1162                 blame_list = setup_blame_list(sb, target, &num_ents);
1163                 if (!blame_list) {
1164                         retval = 1;
1165                         break;
1166                 }
1167         }
1168         diff_flush(&diff_opts);
1169         diff_tree_release_paths(&diff_opts);
1170         return retval;
1174  * The blobs of origin and porigin exactly match, so everything
1175  * origin is suspected for can be blamed on the parent.
1176  */
1177 static void pass_whole_blame(struct scoreboard *sb,
1178                              struct origin *origin, struct origin *porigin)
1180         struct blame_entry *e;
1182         if (!porigin->file.ptr && origin->file.ptr) {
1183                 /* Steal its file */
1184                 porigin->file = origin->file;
1185                 origin->file.ptr = NULL;
1186         }
1187         for (e = sb->ent; e; e = e->next) {
1188                 if (!same_suspect(e->suspect, origin))
1189                         continue;
1190                 origin_incref(porigin);
1191                 origin_decref(e->suspect);
1192                 e->suspect = porigin;
1193         }
1196 #define MAXPARENT 16
1198 static void pass_blame(struct scoreboard *sb, struct origin *origin, int opt)
1200         int i, pass;
1201         struct commit *commit = origin->commit;
1202         struct commit_list *parent;
1203         struct origin *parent_origin[MAXPARENT], *porigin;
1205         memset(parent_origin, 0, sizeof(parent_origin));
1207         /* The first pass looks for unrenamed path to optimize for
1208          * common cases, then we look for renames in the second pass.
1209          */
1210         for (pass = 0; pass < 2; pass++) {
1211                 struct origin *(*find)(struct scoreboard *,
1212                                        struct commit *, struct origin *);
1213                 find = pass ? find_rename : find_origin;
1215                 for (i = 0, parent = commit->parents;
1216                      i < MAXPARENT && parent;
1217                      parent = parent->next, i++) {
1218                         struct commit *p = parent->item;
1219                         int j, same;
1221                         if (parent_origin[i])
1222                                 continue;
1223                         if (parse_commit(p))
1224                                 continue;
1225                         porigin = find(sb, p, origin);
1226                         if (!porigin)
1227                                 continue;
1228                         if (!hashcmp(porigin->blob_sha1, origin->blob_sha1)) {
1229                                 pass_whole_blame(sb, origin, porigin);
1230                                 origin_decref(porigin);
1231                                 goto finish;
1232                         }
1233                         for (j = same = 0; j < i; j++)
1234                                 if (parent_origin[j] &&
1235                                     !hashcmp(parent_origin[j]->blob_sha1,
1236                                              porigin->blob_sha1)) {
1237                                         same = 1;
1238                                         break;
1239                                 }
1240                         if (!same)
1241                                 parent_origin[i] = porigin;
1242                         else
1243                                 origin_decref(porigin);
1244                 }
1245         }
1247         num_commits++;
1248         for (i = 0, parent = commit->parents;
1249              i < MAXPARENT && parent;
1250              parent = parent->next, i++) {
1251                 struct origin *porigin = parent_origin[i];
1252                 if (!porigin)
1253                         continue;
1254                 if (pass_blame_to_parent(sb, origin, porigin))
1255                         goto finish;
1256         }
1258         /*
1259          * Optionally find moves in parents' files.
1260          */
1261         if (opt & PICKAXE_BLAME_MOVE)
1262                 for (i = 0, parent = commit->parents;
1263                      i < MAXPARENT && parent;
1264                      parent = parent->next, i++) {
1265                         struct origin *porigin = parent_origin[i];
1266                         if (!porigin)
1267                                 continue;
1268                         if (find_move_in_parent(sb, origin, porigin))
1269                                 goto finish;
1270                 }
1272         /*
1273          * Optionally find copies from parents' files.
1274          */
1275         if (opt & PICKAXE_BLAME_COPY)
1276                 for (i = 0, parent = commit->parents;
1277                      i < MAXPARENT && parent;
1278                      parent = parent->next, i++) {
1279                         struct origin *porigin = parent_origin[i];
1280                         if (find_copy_in_parent(sb, origin, parent->item,
1281                                                 porigin, opt))
1282                                 goto finish;
1283                 }
1285  finish:
1286         for (i = 0; i < MAXPARENT; i++) {
1287                 if (parent_origin[i]) {
1288                         drop_origin_blob(parent_origin[i]);
1289                         origin_decref(parent_origin[i]);
1290                 }
1291         }
1292         drop_origin_blob(origin);
1296  * Information on commits, used for output.
1297  */
1298 struct commit_info
1300         const char *author;
1301         const char *author_mail;
1302         unsigned long author_time;
1303         const char *author_tz;
1305         /* filled only when asked for details */
1306         const char *committer;
1307         const char *committer_mail;
1308         unsigned long committer_time;
1309         const char *committer_tz;
1311         const char *summary;
1315  * Parse author/committer line in the commit object buffer
1316  */
1317 static void get_ac_line(const char *inbuf, const char *what,
1318                         int bufsz, char *person, const char **mail,
1319                         unsigned long *time, const char **tz)
1321         int len, tzlen, maillen;
1322         char *tmp, *endp, *timepos;
1324         tmp = strstr(inbuf, what);
1325         if (!tmp)
1326                 goto error_out;
1327         tmp += strlen(what);
1328         endp = strchr(tmp, '\n');
1329         if (!endp)
1330                 len = strlen(tmp);
1331         else
1332                 len = endp - tmp;
1333         if (bufsz <= len) {
1334         error_out:
1335                 /* Ugh */
1336                 *mail = *tz = "(unknown)";
1337                 *time = 0;
1338                 return;
1339         }
1340         memcpy(person, tmp, len);
1342         tmp = person;
1343         tmp += len;
1344         *tmp = 0;
1345         while (*tmp != ' ')
1346                 tmp--;
1347         *tz = tmp+1;
1348         tzlen = (person+len)-(tmp+1);
1350         *tmp = 0;
1351         while (*tmp != ' ')
1352                 tmp--;
1353         *time = strtoul(tmp, NULL, 10);
1354         timepos = tmp;
1356         *tmp = 0;
1357         while (*tmp != ' ')
1358                 tmp--;
1359         *mail = tmp + 1;
1360         *tmp = 0;
1361         maillen = timepos - tmp;
1363         if (!mailmap.nr)
1364                 return;
1366         /*
1367          * mailmap expansion may make the name longer.
1368          * make room by pushing stuff down.
1369          */
1370         tmp = person + bufsz - (tzlen + 1);
1371         memmove(tmp, *tz, tzlen);
1372         tmp[tzlen] = 0;
1373         *tz = tmp;
1375         tmp = tmp - (maillen + 1);
1376         memmove(tmp, *mail, maillen);
1377         tmp[maillen] = 0;
1378         *mail = tmp;
1380         /*
1381          * Now, convert e-mail using mailmap
1382          */
1383         map_email(&mailmap, tmp + 1, person, tmp-person-1);
1386 static void get_commit_info(struct commit *commit,
1387                             struct commit_info *ret,
1388                             int detailed)
1390         int len;
1391         char *tmp, *endp;
1392         static char author_buf[1024];
1393         static char committer_buf[1024];
1394         static char summary_buf[1024];
1396         /*
1397          * We've operated without save_commit_buffer, so
1398          * we now need to populate them for output.
1399          */
1400         if (!commit->buffer) {
1401                 enum object_type type;
1402                 unsigned long size;
1403                 commit->buffer =
1404                         read_sha1_file(commit->object.sha1, &type, &size);
1405                 if (!commit->buffer)
1406                         die("Cannot read commit %s",
1407                             sha1_to_hex(commit->object.sha1));
1408         }
1409         ret->author = author_buf;
1410         get_ac_line(commit->buffer, "\nauthor ",
1411                     sizeof(author_buf), author_buf, &ret->author_mail,
1412                     &ret->author_time, &ret->author_tz);
1414         if (!detailed)
1415                 return;
1417         ret->committer = committer_buf;
1418         get_ac_line(commit->buffer, "\ncommitter ",
1419                     sizeof(committer_buf), committer_buf, &ret->committer_mail,
1420                     &ret->committer_time, &ret->committer_tz);
1422         ret->summary = summary_buf;
1423         tmp = strstr(commit->buffer, "\n\n");
1424         if (!tmp) {
1425         error_out:
1426                 sprintf(summary_buf, "(%s)", sha1_to_hex(commit->object.sha1));
1427                 return;
1428         }
1429         tmp += 2;
1430         endp = strchr(tmp, '\n');
1431         if (!endp)
1432                 endp = tmp + strlen(tmp);
1433         len = endp - tmp;
1434         if (len >= sizeof(summary_buf) || len == 0)
1435                 goto error_out;
1436         memcpy(summary_buf, tmp, len);
1437         summary_buf[len] = 0;
1441  * To allow LF and other nonportable characters in pathnames,
1442  * they are c-style quoted as needed.
1443  */
1444 static void write_filename_info(const char *path)
1446         printf("filename ");
1447         write_name_quoted(path, stdout, '\n');
1451  * The blame_entry is found to be guilty for the range.  Mark it
1452  * as such, and show it in incremental output.
1453  */
1454 static void found_guilty_entry(struct blame_entry *ent)
1456         if (ent->guilty)
1457                 return;
1458         ent->guilty = 1;
1459         if (incremental) {
1460                 struct origin *suspect = ent->suspect;
1462                 printf("%s %d %d %d\n",
1463                        sha1_to_hex(suspect->commit->object.sha1),
1464                        ent->s_lno + 1, ent->lno + 1, ent->num_lines);
1465                 if (!(suspect->commit->object.flags & METAINFO_SHOWN)) {
1466                         struct commit_info ci;
1467                         suspect->commit->object.flags |= METAINFO_SHOWN;
1468                         get_commit_info(suspect->commit, &ci, 1);
1469                         printf("author %s\n", ci.author);
1470                         printf("author-mail %s\n", ci.author_mail);
1471                         printf("author-time %lu\n", ci.author_time);
1472                         printf("author-tz %s\n", ci.author_tz);
1473                         printf("committer %s\n", ci.committer);
1474                         printf("committer-mail %s\n", ci.committer_mail);
1475                         printf("committer-time %lu\n", ci.committer_time);
1476                         printf("committer-tz %s\n", ci.committer_tz);
1477                         printf("summary %s\n", ci.summary);
1478                         if (suspect->commit->object.flags & UNINTERESTING)
1479                                 printf("boundary\n");
1480                 }
1481                 write_filename_info(suspect->path);
1482                 maybe_flush_or_die(stdout, "stdout");
1483         }
1487  * The main loop -- while the scoreboard has lines whose true origin
1488  * is still unknown, pick one blame_entry, and allow its current
1489  * suspect to pass blames to its parents.
1490  */
1491 static void assign_blame(struct scoreboard *sb, struct rev_info *revs, int opt)
1493         while (1) {
1494                 struct blame_entry *ent;
1495                 struct commit *commit;
1496                 struct origin *suspect = NULL;
1498                 /* find one suspect to break down */
1499                 for (ent = sb->ent; !suspect && ent; ent = ent->next)
1500                         if (!ent->guilty)
1501                                 suspect = ent->suspect;
1502                 if (!suspect)
1503                         return; /* all done */
1505                 /*
1506                  * We will use this suspect later in the loop,
1507                  * so hold onto it in the meantime.
1508                  */
1509                 origin_incref(suspect);
1510                 commit = suspect->commit;
1511                 if (!commit->object.parsed)
1512                         parse_commit(commit);
1513                 if (!(commit->object.flags & UNINTERESTING) &&
1514                     !(revs->max_age != -1 && commit->date < revs->max_age))
1515                         pass_blame(sb, suspect, opt);
1516                 else {
1517                         commit->object.flags |= UNINTERESTING;
1518                         if (commit->object.parsed)
1519                                 mark_parents_uninteresting(commit);
1520                 }
1521                 /* treat root commit as boundary */
1522                 if (!commit->parents && !show_root)
1523                         commit->object.flags |= UNINTERESTING;
1525                 /* Take responsibility for the remaining entries */
1526                 for (ent = sb->ent; ent; ent = ent->next)
1527                         if (same_suspect(ent->suspect, suspect))
1528                                 found_guilty_entry(ent);
1529                 origin_decref(suspect);
1531                 if (DEBUG) /* sanity */
1532                         sanity_check_refcnt(sb);
1533         }
1536 static const char *format_time(unsigned long time, const char *tz_str,
1537                                int show_raw_time)
1539         static char time_buf[128];
1540         time_t t = time;
1541         int minutes, tz;
1542         struct tm *tm;
1544         if (show_raw_time) {
1545                 sprintf(time_buf, "%lu %s", time, tz_str);
1546                 return time_buf;
1547         }
1549         tz = atoi(tz_str);
1550         minutes = tz < 0 ? -tz : tz;
1551         minutes = (minutes / 100)*60 + (minutes % 100);
1552         minutes = tz < 0 ? -minutes : minutes;
1553         t = time + minutes * 60;
1554         tm = gmtime(&t);
1556         strftime(time_buf, sizeof(time_buf), "%Y-%m-%d %H:%M:%S ", tm);
1557         strcat(time_buf, tz_str);
1558         return time_buf;
1561 #define OUTPUT_ANNOTATE_COMPAT  001
1562 #define OUTPUT_LONG_OBJECT_NAME 002
1563 #define OUTPUT_RAW_TIMESTAMP    004
1564 #define OUTPUT_PORCELAIN        010
1565 #define OUTPUT_SHOW_NAME        020
1566 #define OUTPUT_SHOW_NUMBER      040
1567 #define OUTPUT_SHOW_SCORE      0100
1568 #define OUTPUT_NO_AUTHOR       0200
1570 static void emit_porcelain(struct scoreboard *sb, struct blame_entry *ent)
1572         int cnt;
1573         const char *cp;
1574         struct origin *suspect = ent->suspect;
1575         char hex[41];
1577         strcpy(hex, sha1_to_hex(suspect->commit->object.sha1));
1578         printf("%s%c%d %d %d\n",
1579                hex,
1580                ent->guilty ? ' ' : '*', // purely for debugging
1581                ent->s_lno + 1,
1582                ent->lno + 1,
1583                ent->num_lines);
1584         if (!(suspect->commit->object.flags & METAINFO_SHOWN)) {
1585                 struct commit_info ci;
1586                 suspect->commit->object.flags |= METAINFO_SHOWN;
1587                 get_commit_info(suspect->commit, &ci, 1);
1588                 printf("author %s\n", ci.author);
1589                 printf("author-mail %s\n", ci.author_mail);
1590                 printf("author-time %lu\n", ci.author_time);
1591                 printf("author-tz %s\n", ci.author_tz);
1592                 printf("committer %s\n", ci.committer);
1593                 printf("committer-mail %s\n", ci.committer_mail);
1594                 printf("committer-time %lu\n", ci.committer_time);
1595                 printf("committer-tz %s\n", ci.committer_tz);
1596                 write_filename_info(suspect->path);
1597                 printf("summary %s\n", ci.summary);
1598                 if (suspect->commit->object.flags & UNINTERESTING)
1599                         printf("boundary\n");
1600         }
1601         else if (suspect->commit->object.flags & MORE_THAN_ONE_PATH)
1602                 write_filename_info(suspect->path);
1604         cp = nth_line(sb, ent->lno);
1605         for (cnt = 0; cnt < ent->num_lines; cnt++) {
1606                 char ch;
1607                 if (cnt)
1608                         printf("%s %d %d\n", hex,
1609                                ent->s_lno + 1 + cnt,
1610                                ent->lno + 1 + cnt);
1611                 putchar('\t');
1612                 do {
1613                         ch = *cp++;
1614                         putchar(ch);
1615                 } while (ch != '\n' &&
1616                          cp < sb->final_buf + sb->final_buf_size);
1617         }
1620 static void emit_other(struct scoreboard *sb, struct blame_entry *ent, int opt)
1622         int cnt;
1623         const char *cp;
1624         struct origin *suspect = ent->suspect;
1625         struct commit_info ci;
1626         char hex[41];
1627         int show_raw_time = !!(opt & OUTPUT_RAW_TIMESTAMP);
1629         get_commit_info(suspect->commit, &ci, 1);
1630         strcpy(hex, sha1_to_hex(suspect->commit->object.sha1));
1632         cp = nth_line(sb, ent->lno);
1633         for (cnt = 0; cnt < ent->num_lines; cnt++) {
1634                 char ch;
1635                 int length = (opt & OUTPUT_LONG_OBJECT_NAME) ? 40 : 8;
1637                 if (suspect->commit->object.flags & UNINTERESTING) {
1638                         if (blank_boundary)
1639                                 memset(hex, ' ', length);
1640                         else if (!cmd_is_annotate) {
1641                                 length--;
1642                                 putchar('^');
1643                         }
1644                 }
1646                 printf("%.*s", length, hex);
1647                 if (opt & OUTPUT_ANNOTATE_COMPAT)
1648                         printf("\t(%10s\t%10s\t%d)", ci.author,
1649                                format_time(ci.author_time, ci.author_tz,
1650                                            show_raw_time),
1651                                ent->lno + 1 + cnt);
1652                 else {
1653                         if (opt & OUTPUT_SHOW_SCORE)
1654                                 printf(" %*d %02d",
1655                                        max_score_digits, ent->score,
1656                                        ent->suspect->refcnt);
1657                         if (opt & OUTPUT_SHOW_NAME)
1658                                 printf(" %-*.*s", longest_file, longest_file,
1659                                        suspect->path);
1660                         if (opt & OUTPUT_SHOW_NUMBER)
1661                                 printf(" %*d", max_orig_digits,
1662                                        ent->s_lno + 1 + cnt);
1664                         if (!(opt & OUTPUT_NO_AUTHOR))
1665                                 printf(" (%-*.*s %10s",
1666                                        longest_author, longest_author,
1667                                        ci.author,
1668                                        format_time(ci.author_time,
1669                                                    ci.author_tz,
1670                                                    show_raw_time));
1671                         printf(" %*d) ",
1672                                max_digits, ent->lno + 1 + cnt);
1673                 }
1674                 do {
1675                         ch = *cp++;
1676                         putchar(ch);
1677                 } while (ch != '\n' &&
1678                          cp < sb->final_buf + sb->final_buf_size);
1679         }
1682 static void output(struct scoreboard *sb, int option)
1684         struct blame_entry *ent;
1686         if (option & OUTPUT_PORCELAIN) {
1687                 for (ent = sb->ent; ent; ent = ent->next) {
1688                         struct blame_entry *oth;
1689                         struct origin *suspect = ent->suspect;
1690                         struct commit *commit = suspect->commit;
1691                         if (commit->object.flags & MORE_THAN_ONE_PATH)
1692                                 continue;
1693                         for (oth = ent->next; oth; oth = oth->next) {
1694                                 if ((oth->suspect->commit != commit) ||
1695                                     !strcmp(oth->suspect->path, suspect->path))
1696                                         continue;
1697                                 commit->object.flags |= MORE_THAN_ONE_PATH;
1698                                 break;
1699                         }
1700                 }
1701         }
1703         for (ent = sb->ent; ent; ent = ent->next) {
1704                 if (option & OUTPUT_PORCELAIN)
1705                         emit_porcelain(sb, ent);
1706                 else {
1707                         emit_other(sb, ent, option);
1708                 }
1709         }
1713  * To allow quick access to the contents of nth line in the
1714  * final image, prepare an index in the scoreboard.
1715  */
1716 static int prepare_lines(struct scoreboard *sb)
1718         const char *buf = sb->final_buf;
1719         unsigned long len = sb->final_buf_size;
1720         int num = 0, incomplete = 0, bol = 1;
1722         if (len && buf[len-1] != '\n')
1723                 incomplete++; /* incomplete line at the end */
1724         while (len--) {
1725                 if (bol) {
1726                         sb->lineno = xrealloc(sb->lineno,
1727                                               sizeof(int* ) * (num + 1));
1728                         sb->lineno[num] = buf - sb->final_buf;
1729                         bol = 0;
1730                 }
1731                 if (*buf++ == '\n') {
1732                         num++;
1733                         bol = 1;
1734                 }
1735         }
1736         sb->lineno = xrealloc(sb->lineno,
1737                               sizeof(int* ) * (num + incomplete + 1));
1738         sb->lineno[num + incomplete] = buf - sb->final_buf;
1739         sb->num_lines = num + incomplete;
1740         return sb->num_lines;
1744  * Add phony grafts for use with -S; this is primarily to
1745  * support git-cvsserver that wants to give a linear history
1746  * to its clients.
1747  */
1748 static int read_ancestry(const char *graft_file)
1750         FILE *fp = fopen(graft_file, "r");
1751         char buf[1024];
1752         if (!fp)
1753                 return -1;
1754         while (fgets(buf, sizeof(buf), fp)) {
1755                 /* The format is just "Commit Parent1 Parent2 ...\n" */
1756                 int len = strlen(buf);
1757                 struct commit_graft *graft = read_graft_line(buf, len);
1758                 if (graft)
1759                         register_commit_graft(graft, 0);
1760         }
1761         fclose(fp);
1762         return 0;
1766  * How many columns do we need to show line numbers in decimal?
1767  */
1768 static int lineno_width(int lines)
1770         int i, width;
1772         for (width = 1, i = 10; i <= lines + 1; width++)
1773                 i *= 10;
1774         return width;
1778  * How many columns do we need to show line numbers, authors,
1779  * and filenames?
1780  */
1781 static void find_alignment(struct scoreboard *sb, int *option)
1783         int longest_src_lines = 0;
1784         int longest_dst_lines = 0;
1785         unsigned largest_score = 0;
1786         struct blame_entry *e;
1788         for (e = sb->ent; e; e = e->next) {
1789                 struct origin *suspect = e->suspect;
1790                 struct commit_info ci;
1791                 int num;
1793                 if (strcmp(suspect->path, sb->path))
1794                         *option |= OUTPUT_SHOW_NAME;
1795                 num = strlen(suspect->path);
1796                 if (longest_file < num)
1797                         longest_file = num;
1798                 if (!(suspect->commit->object.flags & METAINFO_SHOWN)) {
1799                         suspect->commit->object.flags |= METAINFO_SHOWN;
1800                         get_commit_info(suspect->commit, &ci, 1);
1801                         num = strlen(ci.author);
1802                         if (longest_author < num)
1803                                 longest_author = num;
1804                 }
1805                 num = e->s_lno + e->num_lines;
1806                 if (longest_src_lines < num)
1807                         longest_src_lines = num;
1808                 num = e->lno + e->num_lines;
1809                 if (longest_dst_lines < num)
1810                         longest_dst_lines = num;
1811                 if (largest_score < ent_score(sb, e))
1812                         largest_score = ent_score(sb, e);
1813         }
1814         max_orig_digits = lineno_width(longest_src_lines);
1815         max_digits = lineno_width(longest_dst_lines);
1816         max_score_digits = lineno_width(largest_score);
1820  * For debugging -- origin is refcounted, and this asserts that
1821  * we do not underflow.
1822  */
1823 static void sanity_check_refcnt(struct scoreboard *sb)
1825         int baa = 0;
1826         struct blame_entry *ent;
1828         for (ent = sb->ent; ent; ent = ent->next) {
1829                 /* Nobody should have zero or negative refcnt */
1830                 if (ent->suspect->refcnt <= 0) {
1831                         fprintf(stderr, "%s in %s has negative refcnt %d\n",
1832                                 ent->suspect->path,
1833                                 sha1_to_hex(ent->suspect->commit->object.sha1),
1834                                 ent->suspect->refcnt);
1835                         baa = 1;
1836                 }
1837         }
1838         for (ent = sb->ent; ent; ent = ent->next) {
1839                 /* Mark the ones that haven't been checked */
1840                 if (0 < ent->suspect->refcnt)
1841                         ent->suspect->refcnt = -ent->suspect->refcnt;
1842         }
1843         for (ent = sb->ent; ent; ent = ent->next) {
1844                 /*
1845                  * ... then pick each and see if they have the the
1846                  * correct refcnt.
1847                  */
1848                 int found;
1849                 struct blame_entry *e;
1850                 struct origin *suspect = ent->suspect;
1852                 if (0 < suspect->refcnt)
1853                         continue;
1854                 suspect->refcnt = -suspect->refcnt; /* Unmark */
1855                 for (found = 0, e = sb->ent; e; e = e->next) {
1856                         if (e->suspect != suspect)
1857                                 continue;
1858                         found++;
1859                 }
1860                 if (suspect->refcnt != found) {
1861                         fprintf(stderr, "%s in %s has refcnt %d, not %d\n",
1862                                 ent->suspect->path,
1863                                 sha1_to_hex(ent->suspect->commit->object.sha1),
1864                                 ent->suspect->refcnt, found);
1865                         baa = 2;
1866                 }
1867         }
1868         if (baa) {
1869                 int opt = 0160;
1870                 find_alignment(sb, &opt);
1871                 output(sb, opt);
1872                 die("Baa %d!", baa);
1873         }
1877  * Used for the command line parsing; check if the path exists
1878  * in the working tree.
1879  */
1880 static int has_path_in_work_tree(const char *path)
1882         struct stat st;
1883         return !lstat(path, &st);
1886 static unsigned parse_score(const char *arg)
1888         char *end;
1889         unsigned long score = strtoul(arg, &end, 10);
1890         if (*end)
1891                 return 0;
1892         return score;
1895 static const char *add_prefix(const char *prefix, const char *path)
1897         if (!prefix || !prefix[0])
1898                 return path;
1899         return prefix_path(prefix, strlen(prefix), path);
1903  * Parsing of (comma separated) one item in the -L option
1904  */
1905 static const char *parse_loc(const char *spec,
1906                              struct scoreboard *sb, long lno,
1907                              long begin, long *ret)
1909         char *term;
1910         const char *line;
1911         long num;
1912         int reg_error;
1913         regex_t regexp;
1914         regmatch_t match[1];
1916         /* Allow "-L <something>,+20" to mean starting at <something>
1917          * for 20 lines, or "-L <something>,-5" for 5 lines ending at
1918          * <something>.
1919          */
1920         if (1 < begin && (spec[0] == '+' || spec[0] == '-')) {
1921                 num = strtol(spec + 1, &term, 10);
1922                 if (term != spec + 1) {
1923                         if (spec[0] == '-')
1924                                 num = 0 - num;
1925                         if (0 < num)
1926                                 *ret = begin + num - 2;
1927                         else if (!num)
1928                                 *ret = begin;
1929                         else
1930                                 *ret = begin + num;
1931                         return term;
1932                 }
1933                 return spec;
1934         }
1935         num = strtol(spec, &term, 10);
1936         if (term != spec) {
1937                 *ret = num;
1938                 return term;
1939         }
1940         if (spec[0] != '/')
1941                 return spec;
1943         /* it could be a regexp of form /.../ */
1944         for (term = (char*) spec + 1; *term && *term != '/'; term++) {
1945                 if (*term == '\\')
1946                         term++;
1947         }
1948         if (*term != '/')
1949                 return spec;
1951         /* try [spec+1 .. term-1] as regexp */
1952         *term = 0;
1953         begin--; /* input is in human terms */
1954         line = nth_line(sb, begin);
1956         if (!(reg_error = regcomp(&regexp, spec + 1, REG_NEWLINE)) &&
1957             !(reg_error = regexec(&regexp, line, 1, match, 0))) {
1958                 const char *cp = line + match[0].rm_so;
1959                 const char *nline;
1961                 while (begin++ < lno) {
1962                         nline = nth_line(sb, begin);
1963                         if (line <= cp && cp < nline)
1964                                 break;
1965                         line = nline;
1966                 }
1967                 *ret = begin;
1968                 regfree(&regexp);
1969                 *term++ = '/';
1970                 return term;
1971         }
1972         else {
1973                 char errbuf[1024];
1974                 regerror(reg_error, &regexp, errbuf, 1024);
1975                 die("-L parameter '%s': %s", spec + 1, errbuf);
1976         }
1980  * Parsing of -L option
1981  */
1982 static void prepare_blame_range(struct scoreboard *sb,
1983                                 const char *bottomtop,
1984                                 long lno,
1985                                 long *bottom, long *top)
1987         const char *term;
1989         term = parse_loc(bottomtop, sb, lno, 1, bottom);
1990         if (*term == ',') {
1991                 term = parse_loc(term + 1, sb, lno, *bottom + 1, top);
1992                 if (*term)
1993                         usage(blame_usage);
1994         }
1995         if (*term)
1996                 usage(blame_usage);
1999 static int git_blame_config(const char *var, const char *value)
2001         if (!strcmp(var, "blame.showroot")) {
2002                 show_root = git_config_bool(var, value);
2003                 return 0;
2004         }
2005         if (!strcmp(var, "blame.blankboundary")) {
2006                 blank_boundary = git_config_bool(var, value);
2007                 return 0;
2008         }
2009         return git_default_config(var, value);
2012 static struct commit *fake_working_tree_commit(const char *path, const char *contents_from)
2014         struct commit *commit;
2015         struct origin *origin;
2016         unsigned char head_sha1[20];
2017         struct strbuf buf;
2018         const char *ident;
2019         time_t now;
2020         int size, len;
2021         struct cache_entry *ce;
2022         unsigned mode;
2024         if (get_sha1("HEAD", head_sha1))
2025                 die("No such ref: HEAD");
2027         time(&now);
2028         commit = xcalloc(1, sizeof(*commit));
2029         commit->parents = xcalloc(1, sizeof(*commit->parents));
2030         commit->parents->item = lookup_commit_reference(head_sha1);
2031         commit->object.parsed = 1;
2032         commit->date = now;
2033         commit->object.type = OBJ_COMMIT;
2035         origin = make_origin(commit, path);
2037         strbuf_init(&buf, 0);
2038         if (!contents_from || strcmp("-", contents_from)) {
2039                 struct stat st;
2040                 const char *read_from;
2041                 unsigned long fin_size;
2043                 if (contents_from) {
2044                         if (stat(contents_from, &st) < 0)
2045                                 die("Cannot stat %s", contents_from);
2046                         read_from = contents_from;
2047                 }
2048                 else {
2049                         if (lstat(path, &st) < 0)
2050                                 die("Cannot lstat %s", path);
2051                         read_from = path;
2052                 }
2053                 fin_size = xsize_t(st.st_size);
2054                 mode = canon_mode(st.st_mode);
2055                 switch (st.st_mode & S_IFMT) {
2056                 case S_IFREG:
2057                         if (strbuf_read_file(&buf, read_from, st.st_size) != st.st_size)
2058                                 die("cannot open or read %s", read_from);
2059                         break;
2060                 case S_IFLNK:
2061                         if (readlink(read_from, buf.buf, buf.alloc) != fin_size)
2062                                 die("cannot readlink %s", read_from);
2063                         buf.len = fin_size;
2064                         break;
2065                 default:
2066                         die("unsupported file type %s", read_from);
2067                 }
2068         }
2069         else {
2070                 /* Reading from stdin */
2071                 contents_from = "standard input";
2072                 mode = 0;
2073                 if (strbuf_read(&buf, 0, 0) < 0)
2074                         die("read error %s from stdin", strerror(errno));
2075         }
2076         convert_to_git(path, buf.buf, buf.len, &buf);
2077         origin->file.ptr = buf.buf;
2078         origin->file.size = buf.len;
2079         pretend_sha1_file(buf.buf, buf.len, OBJ_BLOB, origin->blob_sha1);
2080         commit->util = origin;
2082         /*
2083          * Read the current index, replace the path entry with
2084          * origin->blob_sha1 without mucking with its mode or type
2085          * bits; we are not going to write this index out -- we just
2086          * want to run "diff-index --cached".
2087          */
2088         discard_cache();
2089         read_cache();
2091         len = strlen(path);
2092         if (!mode) {
2093                 int pos = cache_name_pos(path, len);
2094                 if (0 <= pos)
2095                         mode = active_cache[pos]->ce_mode;
2096                 else
2097                         /* Let's not bother reading from HEAD tree */
2098                         mode = S_IFREG | 0644;
2099         }
2100         size = cache_entry_size(len);
2101         ce = xcalloc(1, size);
2102         hashcpy(ce->sha1, origin->blob_sha1);
2103         memcpy(ce->name, path, len);
2104         ce->ce_flags = create_ce_flags(len, 0);
2105         ce->ce_mode = create_ce_mode(mode);
2106         add_cache_entry(ce, ADD_CACHE_OK_TO_ADD|ADD_CACHE_OK_TO_REPLACE);
2108         /*
2109          * We are not going to write this out, so this does not matter
2110          * right now, but someday we might optimize diff-index --cached
2111          * with cache-tree information.
2112          */
2113         cache_tree_invalidate_path(active_cache_tree, path);
2115         commit->buffer = xmalloc(400);
2116         ident = fmt_ident("Not Committed Yet", "not.committed.yet", NULL, 0);
2117         snprintf(commit->buffer, 400,
2118                 "tree 0000000000000000000000000000000000000000\n"
2119                 "parent %s\n"
2120                 "author %s\n"
2121                 "committer %s\n\n"
2122                 "Version of %s from %s\n",
2123                 sha1_to_hex(head_sha1),
2124                 ident, ident, path, contents_from ? contents_from : path);
2125         return commit;
2128 int cmd_blame(int argc, const char **argv, const char *prefix)
2130         struct rev_info revs;
2131         const char *path;
2132         struct scoreboard sb;
2133         struct origin *o;
2134         struct blame_entry *ent;
2135         int i, seen_dashdash, unk, opt;
2136         long bottom, top, lno;
2137         int output_option = 0;
2138         int show_stats = 0;
2139         const char *revs_file = NULL;
2140         const char *final_commit_name = NULL;
2141         enum object_type type;
2142         const char *bottomtop = NULL;
2143         const char *contents_from = NULL;
2145         cmd_is_annotate = !strcmp(argv[0], "annotate");
2147         git_config(git_blame_config);
2148         save_commit_buffer = 0;
2150         opt = 0;
2151         seen_dashdash = 0;
2152         for (unk = i = 1; i < argc; i++) {
2153                 const char *arg = argv[i];
2154                 if (*arg != '-')
2155                         break;
2156                 else if (!strcmp("-b", arg))
2157                         blank_boundary = 1;
2158                 else if (!strcmp("--root", arg))
2159                         show_root = 1;
2160                 else if (!strcmp(arg, "--show-stats"))
2161                         show_stats = 1;
2162                 else if (!strcmp("-c", arg))
2163                         output_option |= OUTPUT_ANNOTATE_COMPAT;
2164                 else if (!strcmp("-t", arg))
2165                         output_option |= OUTPUT_RAW_TIMESTAMP;
2166                 else if (!strcmp("-l", arg))
2167                         output_option |= OUTPUT_LONG_OBJECT_NAME;
2168                 else if (!strcmp("-s", arg))
2169                         output_option |= OUTPUT_NO_AUTHOR;
2170                 else if (!strcmp("-w", arg))
2171                         xdl_opts |= XDF_IGNORE_WHITESPACE;
2172                 else if (!strcmp("-S", arg) && ++i < argc)
2173                         revs_file = argv[i];
2174                 else if (!prefixcmp(arg, "-M")) {
2175                         opt |= PICKAXE_BLAME_MOVE;
2176                         blame_move_score = parse_score(arg+2);
2177                 }
2178                 else if (!prefixcmp(arg, "-C")) {
2179                         /*
2180                          * -C enables copy from removed files;
2181                          * -C -C enables copy from existing files, but only
2182                          *       when blaming a new file;
2183                          * -C -C -C enables copy from existing files for
2184                          *          everybody
2185                          */
2186                         if (opt & PICKAXE_BLAME_COPY_HARDER)
2187                                 opt |= PICKAXE_BLAME_COPY_HARDEST;
2188                         if (opt & PICKAXE_BLAME_COPY)
2189                                 opt |= PICKAXE_BLAME_COPY_HARDER;
2190                         opt |= PICKAXE_BLAME_COPY | PICKAXE_BLAME_MOVE;
2191                         blame_copy_score = parse_score(arg+2);
2192                 }
2193                 else if (!prefixcmp(arg, "-L")) {
2194                         if (!arg[2]) {
2195                                 if (++i >= argc)
2196                                         usage(blame_usage);
2197                                 arg = argv[i];
2198                         }
2199                         else
2200                                 arg += 2;
2201                         if (bottomtop)
2202                                 die("More than one '-L n,m' option given");
2203                         bottomtop = arg;
2204                 }
2205                 else if (!strcmp("--contents", arg)) {
2206                         if (++i >= argc)
2207                                 usage(blame_usage);
2208                         contents_from = argv[i];
2209                 }
2210                 else if (!strcmp("--incremental", arg))
2211                         incremental = 1;
2212                 else if (!strcmp("--score-debug", arg))
2213                         output_option |= OUTPUT_SHOW_SCORE;
2214                 else if (!strcmp("-f", arg) ||
2215                          !strcmp("--show-name", arg))
2216                         output_option |= OUTPUT_SHOW_NAME;
2217                 else if (!strcmp("-n", arg) ||
2218                          !strcmp("--show-number", arg))
2219                         output_option |= OUTPUT_SHOW_NUMBER;
2220                 else if (!strcmp("-p", arg) ||
2221                          !strcmp("--porcelain", arg))
2222                         output_option |= OUTPUT_PORCELAIN;
2223                 else if (!strcmp("--", arg)) {
2224                         seen_dashdash = 1;
2225                         i++;
2226                         break;
2227                 }
2228                 else
2229                         argv[unk++] = arg;
2230         }
2232         if (!blame_move_score)
2233                 blame_move_score = BLAME_DEFAULT_MOVE_SCORE;
2234         if (!blame_copy_score)
2235                 blame_copy_score = BLAME_DEFAULT_COPY_SCORE;
2237         /*
2238          * We have collected options unknown to us in argv[1..unk]
2239          * which are to be passed to revision machinery if we are
2240          * going to do the "bottom" processing.
2241          *
2242          * The remaining are:
2243          *
2244          * (1) if seen_dashdash, its either
2245          *     "-options -- <path>" or
2246          *     "-options -- <path> <rev>".
2247          *     but the latter is allowed only if there is no
2248          *     options that we passed to revision machinery.
2249          *
2250          * (2) otherwise, we may have "--" somewhere later and
2251          *     might be looking at the first one of multiple 'rev'
2252          *     parameters (e.g. " master ^next ^maint -- path").
2253          *     See if there is a dashdash first, and give the
2254          *     arguments before that to revision machinery.
2255          *     After that there must be one 'path'.
2256          *
2257          * (3) otherwise, its one of the three:
2258          *     "-options <path> <rev>"
2259          *     "-options <rev> <path>"
2260          *     "-options <path>"
2261          *     but again the first one is allowed only if
2262          *     there is no options that we passed to revision
2263          *     machinery.
2264          */
2266         if (seen_dashdash) {
2267                 /* (1) */
2268                 if (argc <= i)
2269                         usage(blame_usage);
2270                 path = add_prefix(prefix, argv[i]);
2271                 if (i + 1 == argc - 1) {
2272                         if (unk != 1)
2273                                 usage(blame_usage);
2274                         argv[unk++] = argv[i + 1];
2275                 }
2276                 else if (i + 1 != argc)
2277                         /* garbage at end */
2278                         usage(blame_usage);
2279         }
2280         else {
2281                 int j;
2282                 for (j = i; !seen_dashdash && j < argc; j++)
2283                         if (!strcmp(argv[j], "--"))
2284                                 seen_dashdash = j;
2285                 if (seen_dashdash) {
2286                         /* (2) */
2287                         if (seen_dashdash + 1 != argc - 1)
2288                                 usage(blame_usage);
2289                         path = add_prefix(prefix, argv[seen_dashdash + 1]);
2290                         for (j = i; j < seen_dashdash; j++)
2291                                 argv[unk++] = argv[j];
2292                 }
2293                 else {
2294                         /* (3) */
2295                         if (argc <= i)
2296                                 usage(blame_usage);
2297                         path = add_prefix(prefix, argv[i]);
2298                         if (i + 1 == argc - 1) {
2299                                 final_commit_name = argv[i + 1];
2301                                 /* if (unk == 1) we could be getting
2302                                  * old-style
2303                                  */
2304                                 if (unk == 1 && !has_path_in_work_tree(path)) {
2305                                         path = add_prefix(prefix, argv[i + 1]);
2306                                         final_commit_name = argv[i];
2307                                 }
2308                         }
2309                         else if (i != argc - 1)
2310                                 usage(blame_usage); /* garbage at end */
2312                         setup_work_tree();
2313                         if (!has_path_in_work_tree(path))
2314                                 die("cannot stat path %s: %s",
2315                                     path, strerror(errno));
2316                 }
2317         }
2319         if (final_commit_name)
2320                 argv[unk++] = final_commit_name;
2322         /*
2323          * Now we got rev and path.  We do not want the path pruning
2324          * but we may want "bottom" processing.
2325          */
2326         argv[unk++] = "--"; /* terminate the rev name */
2327         argv[unk] = NULL;
2329         init_revisions(&revs, NULL);
2330         setup_revisions(unk, argv, &revs, NULL);
2331         memset(&sb, 0, sizeof(sb));
2333         /*
2334          * There must be one and only one positive commit in the
2335          * revs->pending array.
2336          */
2337         for (i = 0; i < revs.pending.nr; i++) {
2338                 struct object *obj = revs.pending.objects[i].item;
2339                 if (obj->flags & UNINTERESTING)
2340                         continue;
2341                 while (obj->type == OBJ_TAG)
2342                         obj = deref_tag(obj, NULL, 0);
2343                 if (obj->type != OBJ_COMMIT)
2344                         die("Non commit %s?",
2345                             revs.pending.objects[i].name);
2346                 if (sb.final)
2347                         die("More than one commit to dig from %s and %s?",
2348                             revs.pending.objects[i].name,
2349                             final_commit_name);
2350                 sb.final = (struct commit *) obj;
2351                 final_commit_name = revs.pending.objects[i].name;
2352         }
2354         if (!sb.final) {
2355                 /*
2356                  * "--not A B -- path" without anything positive;
2357                  * do not default to HEAD, but use the working tree
2358                  * or "--contents".
2359                  */
2360                 setup_work_tree();
2361                 sb.final = fake_working_tree_commit(path, contents_from);
2362                 add_pending_object(&revs, &(sb.final->object), ":");
2363         }
2364         else if (contents_from)
2365                 die("Cannot use --contents with final commit object name");
2367         /*
2368          * If we have bottom, this will mark the ancestors of the
2369          * bottom commits we would reach while traversing as
2370          * uninteresting.
2371          */
2372         prepare_revision_walk(&revs);
2374         if (is_null_sha1(sb.final->object.sha1)) {
2375                 char *buf;
2376                 o = sb.final->util;
2377                 buf = xmalloc(o->file.size + 1);
2378                 memcpy(buf, o->file.ptr, o->file.size + 1);
2379                 sb.final_buf = buf;
2380                 sb.final_buf_size = o->file.size;
2381         }
2382         else {
2383                 o = get_origin(&sb, sb.final, path);
2384                 if (fill_blob_sha1(o))
2385                         die("no such path %s in %s", path, final_commit_name);
2387                 sb.final_buf = read_sha1_file(o->blob_sha1, &type,
2388                                               &sb.final_buf_size);
2389                 if (!sb.final_buf)
2390                         die("Cannot read blob %s for path %s",
2391                             sha1_to_hex(o->blob_sha1),
2392                             path);
2393         }
2394         num_read_blob++;
2395         lno = prepare_lines(&sb);
2397         bottom = top = 0;
2398         if (bottomtop)
2399                 prepare_blame_range(&sb, bottomtop, lno, &bottom, &top);
2400         if (bottom && top && top < bottom) {
2401                 long tmp;
2402                 tmp = top; top = bottom; bottom = tmp;
2403         }
2404         if (bottom < 1)
2405                 bottom = 1;
2406         if (top < 1)
2407                 top = lno;
2408         bottom--;
2409         if (lno < top)
2410                 die("file %s has only %lu lines", path, lno);
2412         ent = xcalloc(1, sizeof(*ent));
2413         ent->lno = bottom;
2414         ent->num_lines = top - bottom;
2415         ent->suspect = o;
2416         ent->s_lno = bottom;
2418         sb.ent = ent;
2419         sb.path = path;
2421         if (revs_file && read_ancestry(revs_file))
2422                 die("reading graft file %s failed: %s",
2423                     revs_file, strerror(errno));
2425         read_mailmap(&mailmap, ".mailmap", NULL);
2427         if (!incremental)
2428                 setup_pager();
2430         assign_blame(&sb, &revs, opt);
2432         if (incremental)
2433                 return 0;
2435         coalesce(&sb);
2437         if (!(output_option & OUTPUT_PORCELAIN))
2438                 find_alignment(&sb, &output_option);
2440         output(&sb, output_option);
2441         free((void *)sb.final_buf);
2442         for (ent = sb.ent; ent; ) {
2443                 struct blame_entry *e = ent->next;
2444                 free(ent);
2445                 ent = e;
2446         }
2448         if (show_stats) {
2449                 printf("num read blob: %d\n", num_read_blob);
2450                 printf("num get patch: %d\n", num_get_patch);
2451                 printf("num commits: %d\n", num_commits);
2452         }
2453         return 0;