xmkstemp(): avoid showing truncated template more carefully
[git/git.git] / builtin / blame.c
1 /*
2 * Blame
3 *
4 * Copyright (c) 2006, Junio C Hamano
5 */
6
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 "string-list.h"
20 #include "mailmap.h"
21 #include "parse-options.h"
22 #include "utf8.h"
23 #include "userdiff.h"
24
25 static char blame_usage[] = "git blame [options] [rev-opts] [rev] [--] file";
26
27 static const char *blame_opt_usage[] = {
28 blame_usage,
29 "",
30 "[rev-opts] are documented in git-rev-list(1)",
31 NULL
32 };
33
34 static int longest_file;
35 static int longest_author;
36 static int max_orig_digits;
37 static int max_digits;
38 static int max_score_digits;
39 static int show_root;
40 static int reverse;
41 static int blank_boundary;
42 static int incremental;
43 static int xdl_opts;
44 static int abbrev = -1;
45
46 static enum date_mode blame_date_mode = DATE_ISO8601;
47 static size_t blame_date_width;
48
49 static struct string_list mailmap;
50
51 #ifndef DEBUG
52 #define DEBUG 0
53 #endif
54
55 /* stats */
56 static int num_read_blob;
57 static int num_get_patch;
58 static int num_commits;
59
60 #define PICKAXE_BLAME_MOVE 01
61 #define PICKAXE_BLAME_COPY 02
62 #define PICKAXE_BLAME_COPY_HARDER 04
63 #define PICKAXE_BLAME_COPY_HARDEST 010
64
65 /*
66 * blame for a blame_entry with score lower than these thresholds
67 * is not passed to the parent using move/copy logic.
68 */
69 static unsigned blame_move_score;
70 static unsigned blame_copy_score;
71 #define BLAME_DEFAULT_MOVE_SCORE 20
72 #define BLAME_DEFAULT_COPY_SCORE 40
73
74 /* bits #0..7 in revision.h, #8..11 used for merge_bases() in commit.c */
75 #define METAINFO_SHOWN (1u<<12)
76 #define MORE_THAN_ONE_PATH (1u<<13)
77
78 /*
79 * One blob in a commit that is being suspected
80 */
81 struct origin {
82 int refcnt;
83 struct origin *previous;
84 struct commit *commit;
85 mmfile_t file;
86 unsigned char blob_sha1[20];
87 unsigned mode;
88 char path[FLEX_ARRAY];
89 };
90
91 static int diff_hunks(mmfile_t *file_a, mmfile_t *file_b, long ctxlen,
92 xdl_emit_hunk_consume_func_t hunk_func, void *cb_data)
93 {
94 xpparam_t xpp = {0};
95 xdemitconf_t xecfg = {0};
96 xdemitcb_t ecb = {NULL};
97
98 xpp.flags = xdl_opts;
99 xecfg.ctxlen = ctxlen;
100 xecfg.hunk_func = hunk_func;
101 ecb.priv = cb_data;
102 return xdi_diff(file_a, file_b, &xpp, &xecfg, &ecb);
103 }
104
105 /*
106 * Prepare diff_filespec and convert it using diff textconv API
107 * if the textconv driver exists.
108 * Return 1 if the conversion succeeds, 0 otherwise.
109 */
110 int textconv_object(const char *path,
111 unsigned mode,
112 const unsigned char *sha1,
113 int sha1_valid,
114 char **buf,
115 unsigned long *buf_size)
116 {
117 struct diff_filespec *df;
118 struct userdiff_driver *textconv;
119
120 df = alloc_filespec(path);
121 fill_filespec(df, sha1, sha1_valid, mode);
122 textconv = get_textconv(df);
123 if (!textconv) {
124 free_filespec(df);
125 return 0;
126 }
127
128 *buf_size = fill_textconv(textconv, df, buf);
129 free_filespec(df);
130 return 1;
131 }
132
133 /*
134 * Given an origin, prepare mmfile_t structure to be used by the
135 * diff machinery
136 */
137 static void fill_origin_blob(struct diff_options *opt,
138 struct origin *o, mmfile_t *file)
139 {
140 if (!o->file.ptr) {
141 enum object_type type;
142 unsigned long file_size;
143
144 num_read_blob++;
145 if (DIFF_OPT_TST(opt, ALLOW_TEXTCONV) &&
146 textconv_object(o->path, o->mode, o->blob_sha1, 1, &file->ptr, &file_size))
147 ;
148 else
149 file->ptr = read_sha1_file(o->blob_sha1, &type, &file_size);
150 file->size = file_size;
151
152 if (!file->ptr)
153 die("Cannot read blob %s for path %s",
154 sha1_to_hex(o->blob_sha1),
155 o->path);
156 o->file = *file;
157 }
158 else
159 *file = o->file;
160 }
161
162 /*
163 * Origin is refcounted and usually we keep the blob contents to be
164 * reused.
165 */
166 static inline struct origin *origin_incref(struct origin *o)
167 {
168 if (o)
169 o->refcnt++;
170 return o;
171 }
172
173 static void origin_decref(struct origin *o)
174 {
175 if (o && --o->refcnt <= 0) {
176 if (o->previous)
177 origin_decref(o->previous);
178 free(o->file.ptr);
179 free(o);
180 }
181 }
182
183 static void drop_origin_blob(struct origin *o)
184 {
185 if (o->file.ptr) {
186 free(o->file.ptr);
187 o->file.ptr = NULL;
188 }
189 }
190
191 /*
192 * Each group of lines is described by a blame_entry; it can be split
193 * as we pass blame to the parents. They form a linked list in the
194 * scoreboard structure, sorted by the target line number.
195 */
196 struct blame_entry {
197 struct blame_entry *prev;
198 struct blame_entry *next;
199
200 /* the first line of this group in the final image;
201 * internally all line numbers are 0 based.
202 */
203 int lno;
204
205 /* how many lines this group has */
206 int num_lines;
207
208 /* the commit that introduced this group into the final image */
209 struct origin *suspect;
210
211 /* true if the suspect is truly guilty; false while we have not
212 * checked if the group came from one of its parents.
213 */
214 char guilty;
215
216 /* true if the entry has been scanned for copies in the current parent
217 */
218 char scanned;
219
220 /* the line number of the first line of this group in the
221 * suspect's file; internally all line numbers are 0 based.
222 */
223 int s_lno;
224
225 /* how significant this entry is -- cached to avoid
226 * scanning the lines over and over.
227 */
228 unsigned score;
229 };
230
231 /*
232 * The current state of the blame assignment.
233 */
234 struct scoreboard {
235 /* the final commit (i.e. where we started digging from) */
236 struct commit *final;
237 struct rev_info *revs;
238 const char *path;
239
240 /*
241 * The contents in the final image.
242 * Used by many functions to obtain contents of the nth line,
243 * indexed with scoreboard.lineno[blame_entry.lno].
244 */
245 const char *final_buf;
246 unsigned long final_buf_size;
247
248 /* linked list of blames */
249 struct blame_entry *ent;
250
251 /* look-up a line in the final buffer */
252 int num_lines;
253 int *lineno;
254 };
255
256 static inline int same_suspect(struct origin *a, struct origin *b)
257 {
258 if (a == b)
259 return 1;
260 if (a->commit != b->commit)
261 return 0;
262 return !strcmp(a->path, b->path);
263 }
264
265 static void sanity_check_refcnt(struct scoreboard *);
266
267 /*
268 * If two blame entries that are next to each other came from
269 * contiguous lines in the same origin (i.e. <commit, path> pair),
270 * merge them together.
271 */
272 static void coalesce(struct scoreboard *sb)
273 {
274 struct blame_entry *ent, *next;
275
276 for (ent = sb->ent; ent && (next = ent->next); ent = next) {
277 if (same_suspect(ent->suspect, next->suspect) &&
278 ent->guilty == next->guilty &&
279 ent->s_lno + ent->num_lines == next->s_lno) {
280 ent->num_lines += next->num_lines;
281 ent->next = next->next;
282 if (ent->next)
283 ent->next->prev = ent;
284 origin_decref(next->suspect);
285 free(next);
286 ent->score = 0;
287 next = ent; /* again */
288 }
289 }
290
291 if (DEBUG) /* sanity */
292 sanity_check_refcnt(sb);
293 }
294
295 /*
296 * Given a commit and a path in it, create a new origin structure.
297 * The callers that add blame to the scoreboard should use
298 * get_origin() to obtain shared, refcounted copy instead of calling
299 * this function directly.
300 */
301 static struct origin *make_origin(struct commit *commit, const char *path)
302 {
303 struct origin *o;
304 o = xcalloc(1, sizeof(*o) + strlen(path) + 1);
305 o->commit = commit;
306 o->refcnt = 1;
307 strcpy(o->path, path);
308 return o;
309 }
310
311 /*
312 * Locate an existing origin or create a new one.
313 */
314 static struct origin *get_origin(struct scoreboard *sb,
315 struct commit *commit,
316 const char *path)
317 {
318 struct blame_entry *e;
319
320 for (e = sb->ent; e; e = e->next) {
321 if (e->suspect->commit == commit &&
322 !strcmp(e->suspect->path, path))
323 return origin_incref(e->suspect);
324 }
325 return make_origin(commit, path);
326 }
327
328 /*
329 * Fill the blob_sha1 field of an origin if it hasn't, so that later
330 * call to fill_origin_blob() can use it to locate the data. blob_sha1
331 * for an origin is also used to pass the blame for the entire file to
332 * the parent to detect the case where a child's blob is identical to
333 * that of its parent's.
334 *
335 * This also fills origin->mode for corresponding tree path.
336 */
337 static int fill_blob_sha1_and_mode(struct origin *origin)
338 {
339 if (!is_null_sha1(origin->blob_sha1))
340 return 0;
341 if (get_tree_entry(origin->commit->object.sha1,
342 origin->path,
343 origin->blob_sha1, &origin->mode))
344 goto error_out;
345 if (sha1_object_info(origin->blob_sha1, NULL) != OBJ_BLOB)
346 goto error_out;
347 return 0;
348 error_out:
349 hashclr(origin->blob_sha1);
350 origin->mode = S_IFINVALID;
351 return -1;
352 }
353
354 /*
355 * We have an origin -- check if the same path exists in the
356 * parent and return an origin structure to represent it.
357 */
358 static struct origin *find_origin(struct scoreboard *sb,
359 struct commit *parent,
360 struct origin *origin)
361 {
362 struct origin *porigin = NULL;
363 struct diff_options diff_opts;
364 const char *paths[2];
365
366 if (parent->util) {
367 /*
368 * Each commit object can cache one origin in that
369 * commit. This is a freestanding copy of origin and
370 * not refcounted.
371 */
372 struct origin *cached = parent->util;
373 if (!strcmp(cached->path, origin->path)) {
374 /*
375 * The same path between origin and its parent
376 * without renaming -- the most common case.
377 */
378 porigin = get_origin(sb, parent, cached->path);
379
380 /*
381 * If the origin was newly created (i.e. get_origin
382 * would call make_origin if none is found in the
383 * scoreboard), it does not know the blob_sha1/mode,
384 * so copy it. Otherwise porigin was in the
385 * scoreboard and already knows blob_sha1/mode.
386 */
387 if (porigin->refcnt == 1) {
388 hashcpy(porigin->blob_sha1, cached->blob_sha1);
389 porigin->mode = cached->mode;
390 }
391 return porigin;
392 }
393 /* otherwise it was not very useful; free it */
394 free(parent->util);
395 parent->util = NULL;
396 }
397
398 /* See if the origin->path is different between parent
399 * and origin first. Most of the time they are the
400 * same and diff-tree is fairly efficient about this.
401 */
402 diff_setup(&diff_opts);
403 DIFF_OPT_SET(&diff_opts, RECURSIVE);
404 diff_opts.detect_rename = 0;
405 diff_opts.output_format = DIFF_FORMAT_NO_OUTPUT;
406 paths[0] = origin->path;
407 paths[1] = NULL;
408
409 diff_tree_setup_paths(paths, &diff_opts);
410 diff_setup_done(&diff_opts);
411
412 if (is_null_sha1(origin->commit->object.sha1))
413 do_diff_cache(parent->tree->object.sha1, &diff_opts);
414 else
415 diff_tree_sha1(parent->tree->object.sha1,
416 origin->commit->tree->object.sha1,
417 "", &diff_opts);
418 diffcore_std(&diff_opts);
419
420 if (!diff_queued_diff.nr) {
421 /* The path is the same as parent */
422 porigin = get_origin(sb, parent, origin->path);
423 hashcpy(porigin->blob_sha1, origin->blob_sha1);
424 porigin->mode = origin->mode;
425 } else {
426 /*
427 * Since origin->path is a pathspec, if the parent
428 * commit had it as a directory, we will see a whole
429 * bunch of deletion of files in the directory that we
430 * do not care about.
431 */
432 int i;
433 struct diff_filepair *p = NULL;
434 for (i = 0; i < diff_queued_diff.nr; i++) {
435 const char *name;
436 p = diff_queued_diff.queue[i];
437 name = p->one->path ? p->one->path : p->two->path;
438 if (!strcmp(name, origin->path))
439 break;
440 }
441 if (!p)
442 die("internal error in blame::find_origin");
443 switch (p->status) {
444 default:
445 die("internal error in blame::find_origin (%c)",
446 p->status);
447 case 'M':
448 porigin = get_origin(sb, parent, origin->path);
449 hashcpy(porigin->blob_sha1, p->one->sha1);
450 porigin->mode = p->one->mode;
451 break;
452 case 'A':
453 case 'T':
454 /* Did not exist in parent, or type changed */
455 break;
456 }
457 }
458 diff_flush(&diff_opts);
459 diff_tree_release_paths(&diff_opts);
460 if (porigin) {
461 /*
462 * Create a freestanding copy that is not part of
463 * the refcounted origin found in the scoreboard, and
464 * cache it in the commit.
465 */
466 struct origin *cached;
467
468 cached = make_origin(porigin->commit, porigin->path);
469 hashcpy(cached->blob_sha1, porigin->blob_sha1);
470 cached->mode = porigin->mode;
471 parent->util = cached;
472 }
473 return porigin;
474 }
475
476 /*
477 * We have an origin -- find the path that corresponds to it in its
478 * parent and return an origin structure to represent it.
479 */
480 static struct origin *find_rename(struct scoreboard *sb,
481 struct commit *parent,
482 struct origin *origin)
483 {
484 struct origin *porigin = NULL;
485 struct diff_options diff_opts;
486 int i;
487 const char *paths[2];
488
489 diff_setup(&diff_opts);
490 DIFF_OPT_SET(&diff_opts, RECURSIVE);
491 diff_opts.detect_rename = DIFF_DETECT_RENAME;
492 diff_opts.output_format = DIFF_FORMAT_NO_OUTPUT;
493 diff_opts.single_follow = origin->path;
494 paths[0] = NULL;
495 diff_tree_setup_paths(paths, &diff_opts);
496 diff_setup_done(&diff_opts);
497
498 if (is_null_sha1(origin->commit->object.sha1))
499 do_diff_cache(parent->tree->object.sha1, &diff_opts);
500 else
501 diff_tree_sha1(parent->tree->object.sha1,
502 origin->commit->tree->object.sha1,
503 "", &diff_opts);
504 diffcore_std(&diff_opts);
505
506 for (i = 0; i < diff_queued_diff.nr; i++) {
507 struct diff_filepair *p = diff_queued_diff.queue[i];
508 if ((p->status == 'R' || p->status == 'C') &&
509 !strcmp(p->two->path, origin->path)) {
510 porigin = get_origin(sb, parent, p->one->path);
511 hashcpy(porigin->blob_sha1, p->one->sha1);
512 porigin->mode = p->one->mode;
513 break;
514 }
515 }
516 diff_flush(&diff_opts);
517 diff_tree_release_paths(&diff_opts);
518 return porigin;
519 }
520
521 /*
522 * Link in a new blame entry to the scoreboard. Entries that cover the
523 * same line range have been removed from the scoreboard previously.
524 */
525 static void add_blame_entry(struct scoreboard *sb, struct blame_entry *e)
526 {
527 struct blame_entry *ent, *prev = NULL;
528
529 origin_incref(e->suspect);
530
531 for (ent = sb->ent; ent && ent->lno < e->lno; ent = ent->next)
532 prev = ent;
533
534 /* prev, if not NULL, is the last one that is below e */
535 e->prev = prev;
536 if (prev) {
537 e->next = prev->next;
538 prev->next = e;
539 }
540 else {
541 e->next = sb->ent;
542 sb->ent = e;
543 }
544 if (e->next)
545 e->next->prev = e;
546 }
547
548 /*
549 * src typically is on-stack; we want to copy the information in it to
550 * a malloced blame_entry that is already on the linked list of the
551 * scoreboard. The origin of dst loses a refcnt while the origin of src
552 * gains one.
553 */
554 static void dup_entry(struct blame_entry *dst, struct blame_entry *src)
555 {
556 struct blame_entry *p, *n;
557
558 p = dst->prev;
559 n = dst->next;
560 origin_incref(src->suspect);
561 origin_decref(dst->suspect);
562 memcpy(dst, src, sizeof(*src));
563 dst->prev = p;
564 dst->next = n;
565 dst->score = 0;
566 }
567
568 static const char *nth_line(struct scoreboard *sb, int lno)
569 {
570 return sb->final_buf + sb->lineno[lno];
571 }
572
573 /*
574 * It is known that lines between tlno to same came from parent, and e
575 * has an overlap with that range. it also is known that parent's
576 * line plno corresponds to e's line tlno.
577 *
578 * <---- e ----->
579 * <------>
580 * <------------>
581 * <------------>
582 * <------------------>
583 *
584 * Split e into potentially three parts; before this chunk, the chunk
585 * to be blamed for the parent, and after that portion.
586 */
587 static void split_overlap(struct blame_entry *split,
588 struct blame_entry *e,
589 int tlno, int plno, int same,
590 struct origin *parent)
591 {
592 int chunk_end_lno;
593 memset(split, 0, sizeof(struct blame_entry [3]));
594
595 if (e->s_lno < tlno) {
596 /* there is a pre-chunk part not blamed on parent */
597 split[0].suspect = origin_incref(e->suspect);
598 split[0].lno = e->lno;
599 split[0].s_lno = e->s_lno;
600 split[0].num_lines = tlno - e->s_lno;
601 split[1].lno = e->lno + tlno - e->s_lno;
602 split[1].s_lno = plno;
603 }
604 else {
605 split[1].lno = e->lno;
606 split[1].s_lno = plno + (e->s_lno - tlno);
607 }
608
609 if (same < e->s_lno + e->num_lines) {
610 /* there is a post-chunk part not blamed on parent */
611 split[2].suspect = origin_incref(e->suspect);
612 split[2].lno = e->lno + (same - e->s_lno);
613 split[2].s_lno = e->s_lno + (same - e->s_lno);
614 split[2].num_lines = e->s_lno + e->num_lines - same;
615 chunk_end_lno = split[2].lno;
616 }
617 else
618 chunk_end_lno = e->lno + e->num_lines;
619 split[1].num_lines = chunk_end_lno - split[1].lno;
620
621 /*
622 * if it turns out there is nothing to blame the parent for,
623 * forget about the splitting. !split[1].suspect signals this.
624 */
625 if (split[1].num_lines < 1)
626 return;
627 split[1].suspect = origin_incref(parent);
628 }
629
630 /*
631 * split_overlap() divided an existing blame e into up to three parts
632 * in split. Adjust the linked list of blames in the scoreboard to
633 * reflect the split.
634 */
635 static void split_blame(struct scoreboard *sb,
636 struct blame_entry *split,
637 struct blame_entry *e)
638 {
639 struct blame_entry *new_entry;
640
641 if (split[0].suspect && split[2].suspect) {
642 /* The first part (reuse storage for the existing entry e) */
643 dup_entry(e, &split[0]);
644
645 /* The last part -- me */
646 new_entry = xmalloc(sizeof(*new_entry));
647 memcpy(new_entry, &(split[2]), sizeof(struct blame_entry));
648 add_blame_entry(sb, new_entry);
649
650 /* ... and the middle part -- parent */
651 new_entry = xmalloc(sizeof(*new_entry));
652 memcpy(new_entry, &(split[1]), sizeof(struct blame_entry));
653 add_blame_entry(sb, new_entry);
654 }
655 else if (!split[0].suspect && !split[2].suspect)
656 /*
657 * The parent covers the entire area; reuse storage for
658 * e and replace it with the parent.
659 */
660 dup_entry(e, &split[1]);
661 else if (split[0].suspect) {
662 /* me and then parent */
663 dup_entry(e, &split[0]);
664
665 new_entry = xmalloc(sizeof(*new_entry));
666 memcpy(new_entry, &(split[1]), sizeof(struct blame_entry));
667 add_blame_entry(sb, new_entry);
668 }
669 else {
670 /* parent and then me */
671 dup_entry(e, &split[1]);
672
673 new_entry = xmalloc(sizeof(*new_entry));
674 memcpy(new_entry, &(split[2]), sizeof(struct blame_entry));
675 add_blame_entry(sb, new_entry);
676 }
677
678 if (DEBUG) { /* sanity */
679 struct blame_entry *ent;
680 int lno = sb->ent->lno, corrupt = 0;
681
682 for (ent = sb->ent; ent; ent = ent->next) {
683 if (lno != ent->lno)
684 corrupt = 1;
685 if (ent->s_lno < 0)
686 corrupt = 1;
687 lno += ent->num_lines;
688 }
689 if (corrupt) {
690 lno = sb->ent->lno;
691 for (ent = sb->ent; ent; ent = ent->next) {
692 printf("L %8d l %8d n %8d\n",
693 lno, ent->lno, ent->num_lines);
694 lno = ent->lno + ent->num_lines;
695 }
696 die("oops");
697 }
698 }
699 }
700
701 /*
702 * After splitting the blame, the origins used by the
703 * on-stack blame_entry should lose one refcnt each.
704 */
705 static void decref_split(struct blame_entry *split)
706 {
707 int i;
708
709 for (i = 0; i < 3; i++)
710 origin_decref(split[i].suspect);
711 }
712
713 /*
714 * Helper for blame_chunk(). blame_entry e is known to overlap with
715 * the patch hunk; split it and pass blame to the parent.
716 */
717 static void blame_overlap(struct scoreboard *sb, struct blame_entry *e,
718 int tlno, int plno, int same,
719 struct origin *parent)
720 {
721 struct blame_entry split[3];
722
723 split_overlap(split, e, tlno, plno, same, parent);
724 if (split[1].suspect)
725 split_blame(sb, split, e);
726 decref_split(split);
727 }
728
729 /*
730 * Find the line number of the last line the target is suspected for.
731 */
732 static int find_last_in_target(struct scoreboard *sb, struct origin *target)
733 {
734 struct blame_entry *e;
735 int last_in_target = -1;
736
737 for (e = sb->ent; e; e = e->next) {
738 if (e->guilty || !same_suspect(e->suspect, target))
739 continue;
740 if (last_in_target < e->s_lno + e->num_lines)
741 last_in_target = e->s_lno + e->num_lines;
742 }
743 return last_in_target;
744 }
745
746 /*
747 * Process one hunk from the patch between the current suspect for
748 * blame_entry e and its parent. Find and split the overlap, and
749 * pass blame to the overlapping part to the parent.
750 */
751 static void blame_chunk(struct scoreboard *sb,
752 int tlno, int plno, int same,
753 struct origin *target, struct origin *parent)
754 {
755 struct blame_entry *e;
756
757 for (e = sb->ent; e; e = e->next) {
758 if (e->guilty || !same_suspect(e->suspect, target))
759 continue;
760 if (same <= e->s_lno)
761 continue;
762 if (tlno < e->s_lno + e->num_lines)
763 blame_overlap(sb, e, tlno, plno, same, parent);
764 }
765 }
766
767 struct blame_chunk_cb_data {
768 struct scoreboard *sb;
769 struct origin *target;
770 struct origin *parent;
771 long plno;
772 long tlno;
773 };
774
775 static int blame_chunk_cb(long start_a, long count_a,
776 long start_b, long count_b, void *data)
777 {
778 struct blame_chunk_cb_data *d = data;
779 blame_chunk(d->sb, d->tlno, d->plno, start_b, d->target, d->parent);
780 d->plno = start_a + count_a;
781 d->tlno = start_b + count_b;
782 return 0;
783 }
784
785 /*
786 * We are looking at the origin 'target' and aiming to pass blame
787 * for the lines it is suspected to its parent. Run diff to find
788 * which lines came from parent and pass blame for them.
789 */
790 static int pass_blame_to_parent(struct scoreboard *sb,
791 struct origin *target,
792 struct origin *parent)
793 {
794 int last_in_target;
795 mmfile_t file_p, file_o;
796 struct blame_chunk_cb_data d;
797
798 memset(&d, 0, sizeof(d));
799 d.sb = sb; d.target = target; d.parent = parent;
800 last_in_target = find_last_in_target(sb, target);
801 if (last_in_target < 0)
802 return 1; /* nothing remains for this target */
803
804 fill_origin_blob(&sb->revs->diffopt, parent, &file_p);
805 fill_origin_blob(&sb->revs->diffopt, target, &file_o);
806 num_get_patch++;
807
808 diff_hunks(&file_p, &file_o, 0, blame_chunk_cb, &d);
809 /* The rest (i.e. anything after tlno) are the same as the parent */
810 blame_chunk(sb, d.tlno, d.plno, last_in_target, target, parent);
811
812 return 0;
813 }
814
815 /*
816 * The lines in blame_entry after splitting blames many times can become
817 * very small and trivial, and at some point it becomes pointless to
818 * blame the parents. E.g. "\t\t}\n\t}\n\n" appears everywhere in any
819 * ordinary C program, and it is not worth to say it was copied from
820 * totally unrelated file in the parent.
821 *
822 * Compute how trivial the lines in the blame_entry are.
823 */
824 static unsigned ent_score(struct scoreboard *sb, struct blame_entry *e)
825 {
826 unsigned score;
827 const char *cp, *ep;
828
829 if (e->score)
830 return e->score;
831
832 score = 1;
833 cp = nth_line(sb, e->lno);
834 ep = nth_line(sb, e->lno + e->num_lines);
835 while (cp < ep) {
836 unsigned ch = *((unsigned char *)cp);
837 if (isalnum(ch))
838 score++;
839 cp++;
840 }
841 e->score = score;
842 return score;
843 }
844
845 /*
846 * best_so_far[] and this[] are both a split of an existing blame_entry
847 * that passes blame to the parent. Maintain best_so_far the best split
848 * so far, by comparing this and best_so_far and copying this into
849 * bst_so_far as needed.
850 */
851 static void copy_split_if_better(struct scoreboard *sb,
852 struct blame_entry *best_so_far,
853 struct blame_entry *this)
854 {
855 int i;
856
857 if (!this[1].suspect)
858 return;
859 if (best_so_far[1].suspect) {
860 if (ent_score(sb, &this[1]) < ent_score(sb, &best_so_far[1]))
861 return;
862 }
863
864 for (i = 0; i < 3; i++)
865 origin_incref(this[i].suspect);
866 decref_split(best_so_far);
867 memcpy(best_so_far, this, sizeof(struct blame_entry [3]));
868 }
869
870 /*
871 * We are looking at a part of the final image represented by
872 * ent (tlno and same are offset by ent->s_lno).
873 * tlno is where we are looking at in the final image.
874 * up to (but not including) same match preimage.
875 * plno is where we are looking at in the preimage.
876 *
877 * <-------------- final image ---------------------->
878 * <------ent------>
879 * ^tlno ^same
880 * <---------preimage----->
881 * ^plno
882 *
883 * All line numbers are 0-based.
884 */
885 static void handle_split(struct scoreboard *sb,
886 struct blame_entry *ent,
887 int tlno, int plno, int same,
888 struct origin *parent,
889 struct blame_entry *split)
890 {
891 if (ent->num_lines <= tlno)
892 return;
893 if (tlno < same) {
894 struct blame_entry this[3];
895 tlno += ent->s_lno;
896 same += ent->s_lno;
897 split_overlap(this, ent, tlno, plno, same, parent);
898 copy_split_if_better(sb, split, this);
899 decref_split(this);
900 }
901 }
902
903 struct handle_split_cb_data {
904 struct scoreboard *sb;
905 struct blame_entry *ent;
906 struct origin *parent;
907 struct blame_entry *split;
908 long plno;
909 long tlno;
910 };
911
912 static int handle_split_cb(long start_a, long count_a,
913 long start_b, long count_b, void *data)
914 {
915 struct handle_split_cb_data *d = data;
916 handle_split(d->sb, d->ent, d->tlno, d->plno, start_b, d->parent,
917 d->split);
918 d->plno = start_a + count_a;
919 d->tlno = start_b + count_b;
920 return 0;
921 }
922
923 /*
924 * Find the lines from parent that are the same as ent so that
925 * we can pass blames to it. file_p has the blob contents for
926 * the parent.
927 */
928 static void find_copy_in_blob(struct scoreboard *sb,
929 struct blame_entry *ent,
930 struct origin *parent,
931 struct blame_entry *split,
932 mmfile_t *file_p)
933 {
934 const char *cp;
935 int cnt;
936 mmfile_t file_o;
937 struct handle_split_cb_data d;
938
939 memset(&d, 0, sizeof(d));
940 d.sb = sb; d.ent = ent; d.parent = parent; d.split = split;
941 /*
942 * Prepare mmfile that contains only the lines in ent.
943 */
944 cp = nth_line(sb, ent->lno);
945 file_o.ptr = (char *) cp;
946 cnt = ent->num_lines;
947
948 while (cnt && cp < sb->final_buf + sb->final_buf_size) {
949 if (*cp++ == '\n')
950 cnt--;
951 }
952 file_o.size = cp - file_o.ptr;
953
954 /*
955 * file_o is a part of final image we are annotating.
956 * file_p partially may match that image.
957 */
958 memset(split, 0, sizeof(struct blame_entry [3]));
959 diff_hunks(file_p, &file_o, 1, handle_split_cb, &d);
960 /* remainder, if any, all match the preimage */
961 handle_split(sb, ent, d.tlno, d.plno, ent->num_lines, parent, split);
962 }
963
964 /*
965 * See if lines currently target is suspected for can be attributed to
966 * parent.
967 */
968 static int find_move_in_parent(struct scoreboard *sb,
969 struct origin *target,
970 struct origin *parent)
971 {
972 int last_in_target, made_progress;
973 struct blame_entry *e, split[3];
974 mmfile_t file_p;
975
976 last_in_target = find_last_in_target(sb, target);
977 if (last_in_target < 0)
978 return 1; /* nothing remains for this target */
979
980 fill_origin_blob(&sb->revs->diffopt, parent, &file_p);
981 if (!file_p.ptr)
982 return 0;
983
984 made_progress = 1;
985 while (made_progress) {
986 made_progress = 0;
987 for (e = sb->ent; e; e = e->next) {
988 if (e->guilty || !same_suspect(e->suspect, target) ||
989 ent_score(sb, e) < blame_move_score)
990 continue;
991 find_copy_in_blob(sb, e, parent, split, &file_p);
992 if (split[1].suspect &&
993 blame_move_score < ent_score(sb, &split[1])) {
994 split_blame(sb, split, e);
995 made_progress = 1;
996 }
997 decref_split(split);
998 }
999 }
1000 return 0;
1001 }
1002
1003 struct blame_list {
1004 struct blame_entry *ent;
1005 struct blame_entry split[3];
1006 };
1007
1008 /*
1009 * Count the number of entries the target is suspected for,
1010 * and prepare a list of entry and the best split.
1011 */
1012 static struct blame_list *setup_blame_list(struct scoreboard *sb,
1013 struct origin *target,
1014 int min_score,
1015 int *num_ents_p)
1016 {
1017 struct blame_entry *e;
1018 int num_ents, i;
1019 struct blame_list *blame_list = NULL;
1020
1021 for (e = sb->ent, num_ents = 0; e; e = e->next)
1022 if (!e->scanned && !e->guilty &&
1023 same_suspect(e->suspect, target) &&
1024 min_score < ent_score(sb, e))
1025 num_ents++;
1026 if (num_ents) {
1027 blame_list = xcalloc(num_ents, sizeof(struct blame_list));
1028 for (e = sb->ent, i = 0; e; e = e->next)
1029 if (!e->scanned && !e->guilty &&
1030 same_suspect(e->suspect, target) &&
1031 min_score < ent_score(sb, e))
1032 blame_list[i++].ent = e;
1033 }
1034 *num_ents_p = num_ents;
1035 return blame_list;
1036 }
1037
1038 /*
1039 * Reset the scanned status on all entries.
1040 */
1041 static void reset_scanned_flag(struct scoreboard *sb)
1042 {
1043 struct blame_entry *e;
1044 for (e = sb->ent; e; e = e->next)
1045 e->scanned = 0;
1046 }
1047
1048 /*
1049 * For lines target is suspected for, see if we can find code movement
1050 * across file boundary from the parent commit. porigin is the path
1051 * in the parent we already tried.
1052 */
1053 static int find_copy_in_parent(struct scoreboard *sb,
1054 struct origin *target,
1055 struct commit *parent,
1056 struct origin *porigin,
1057 int opt)
1058 {
1059 struct diff_options diff_opts;
1060 const char *paths[1];
1061 int i, j;
1062 int retval;
1063 struct blame_list *blame_list;
1064 int num_ents;
1065
1066 blame_list = setup_blame_list(sb, target, blame_copy_score, &num_ents);
1067 if (!blame_list)
1068 return 1; /* nothing remains for this target */
1069
1070 diff_setup(&diff_opts);
1071 DIFF_OPT_SET(&diff_opts, RECURSIVE);
1072 diff_opts.output_format = DIFF_FORMAT_NO_OUTPUT;
1073
1074 paths[0] = NULL;
1075 diff_tree_setup_paths(paths, &diff_opts);
1076 diff_setup_done(&diff_opts);
1077
1078 /* Try "find copies harder" on new path if requested;
1079 * we do not want to use diffcore_rename() actually to
1080 * match things up; find_copies_harder is set only to
1081 * force diff_tree_sha1() to feed all filepairs to diff_queue,
1082 * and this code needs to be after diff_setup_done(), which
1083 * usually makes find-copies-harder imply copy detection.
1084 */
1085 if ((opt & PICKAXE_BLAME_COPY_HARDEST)
1086 || ((opt & PICKAXE_BLAME_COPY_HARDER)
1087 && (!porigin || strcmp(target->path, porigin->path))))
1088 DIFF_OPT_SET(&diff_opts, FIND_COPIES_HARDER);
1089
1090 if (is_null_sha1(target->commit->object.sha1))
1091 do_diff_cache(parent->tree->object.sha1, &diff_opts);
1092 else
1093 diff_tree_sha1(parent->tree->object.sha1,
1094 target->commit->tree->object.sha1,
1095 "", &diff_opts);
1096
1097 if (!DIFF_OPT_TST(&diff_opts, FIND_COPIES_HARDER))
1098 diffcore_std(&diff_opts);
1099
1100 retval = 0;
1101 while (1) {
1102 int made_progress = 0;
1103
1104 for (i = 0; i < diff_queued_diff.nr; i++) {
1105 struct diff_filepair *p = diff_queued_diff.queue[i];
1106 struct origin *norigin;
1107 mmfile_t file_p;
1108 struct blame_entry this[3];
1109
1110 if (!DIFF_FILE_VALID(p->one))
1111 continue; /* does not exist in parent */
1112 if (S_ISGITLINK(p->one->mode))
1113 continue; /* ignore git links */
1114 if (porigin && !strcmp(p->one->path, porigin->path))
1115 /* find_move already dealt with this path */
1116 continue;
1117
1118 norigin = get_origin(sb, parent, p->one->path);
1119 hashcpy(norigin->blob_sha1, p->one->sha1);
1120 norigin->mode = p->one->mode;
1121 fill_origin_blob(&sb->revs->diffopt, norigin, &file_p);
1122 if (!file_p.ptr)
1123 continue;
1124
1125 for (j = 0; j < num_ents; j++) {
1126 find_copy_in_blob(sb, blame_list[j].ent,
1127 norigin, this, &file_p);
1128 copy_split_if_better(sb, blame_list[j].split,
1129 this);
1130 decref_split(this);
1131 }
1132 origin_decref(norigin);
1133 }
1134
1135 for (j = 0; j < num_ents; j++) {
1136 struct blame_entry *split = blame_list[j].split;
1137 if (split[1].suspect &&
1138 blame_copy_score < ent_score(sb, &split[1])) {
1139 split_blame(sb, split, blame_list[j].ent);
1140 made_progress = 1;
1141 }
1142 else
1143 blame_list[j].ent->scanned = 1;
1144 decref_split(split);
1145 }
1146 free(blame_list);
1147
1148 if (!made_progress)
1149 break;
1150 blame_list = setup_blame_list(sb, target, blame_copy_score, &num_ents);
1151 if (!blame_list) {
1152 retval = 1;
1153 break;
1154 }
1155 }
1156 reset_scanned_flag(sb);
1157 diff_flush(&diff_opts);
1158 diff_tree_release_paths(&diff_opts);
1159 return retval;
1160 }
1161
1162 /*
1163 * The blobs of origin and porigin exactly match, so everything
1164 * origin is suspected for can be blamed on the parent.
1165 */
1166 static void pass_whole_blame(struct scoreboard *sb,
1167 struct origin *origin, struct origin *porigin)
1168 {
1169 struct blame_entry *e;
1170
1171 if (!porigin->file.ptr && origin->file.ptr) {
1172 /* Steal its file */
1173 porigin->file = origin->file;
1174 origin->file.ptr = NULL;
1175 }
1176 for (e = sb->ent; e; e = e->next) {
1177 if (!same_suspect(e->suspect, origin))
1178 continue;
1179 origin_incref(porigin);
1180 origin_decref(e->suspect);
1181 e->suspect = porigin;
1182 }
1183 }
1184
1185 /*
1186 * We pass blame from the current commit to its parents. We keep saying
1187 * "parent" (and "porigin"), but what we mean is to find scapegoat to
1188 * exonerate ourselves.
1189 */
1190 static struct commit_list *first_scapegoat(struct rev_info *revs, struct commit *commit)
1191 {
1192 if (!reverse)
1193 return commit->parents;
1194 return lookup_decoration(&revs->children, &commit->object);
1195 }
1196
1197 static int num_scapegoats(struct rev_info *revs, struct commit *commit)
1198 {
1199 int cnt;
1200 struct commit_list *l = first_scapegoat(revs, commit);
1201 for (cnt = 0; l; l = l->next)
1202 cnt++;
1203 return cnt;
1204 }
1205
1206 #define MAXSG 16
1207
1208 static void pass_blame(struct scoreboard *sb, struct origin *origin, int opt)
1209 {
1210 struct rev_info *revs = sb->revs;
1211 int i, pass, num_sg;
1212 struct commit *commit = origin->commit;
1213 struct commit_list *sg;
1214 struct origin *sg_buf[MAXSG];
1215 struct origin *porigin, **sg_origin = sg_buf;
1216
1217 num_sg = num_scapegoats(revs, commit);
1218 if (!num_sg)
1219 goto finish;
1220 else if (num_sg < ARRAY_SIZE(sg_buf))
1221 memset(sg_buf, 0, sizeof(sg_buf));
1222 else
1223 sg_origin = xcalloc(num_sg, sizeof(*sg_origin));
1224
1225 /*
1226 * The first pass looks for unrenamed path to optimize for
1227 * common cases, then we look for renames in the second pass.
1228 */
1229 for (pass = 0; pass < 2; pass++) {
1230 struct origin *(*find)(struct scoreboard *,
1231 struct commit *, struct origin *);
1232 find = pass ? find_rename : find_origin;
1233
1234 for (i = 0, sg = first_scapegoat(revs, commit);
1235 i < num_sg && sg;
1236 sg = sg->next, i++) {
1237 struct commit *p = sg->item;
1238 int j, same;
1239
1240 if (sg_origin[i])
1241 continue;
1242 if (parse_commit(p))
1243 continue;
1244 porigin = find(sb, p, origin);
1245 if (!porigin)
1246 continue;
1247 if (!hashcmp(porigin->blob_sha1, origin->blob_sha1)) {
1248 pass_whole_blame(sb, origin, porigin);
1249 origin_decref(porigin);
1250 goto finish;
1251 }
1252 for (j = same = 0; j < i; j++)
1253 if (sg_origin[j] &&
1254 !hashcmp(sg_origin[j]->blob_sha1,
1255 porigin->blob_sha1)) {
1256 same = 1;
1257 break;
1258 }
1259 if (!same)
1260 sg_origin[i] = porigin;
1261 else
1262 origin_decref(porigin);
1263 }
1264 }
1265
1266 num_commits++;
1267 for (i = 0, sg = first_scapegoat(revs, commit);
1268 i < num_sg && sg;
1269 sg = sg->next, i++) {
1270 struct origin *porigin = sg_origin[i];
1271 if (!porigin)
1272 continue;
1273 if (!origin->previous) {
1274 origin_incref(porigin);
1275 origin->previous = porigin;
1276 }
1277 if (pass_blame_to_parent(sb, origin, porigin))
1278 goto finish;
1279 }
1280
1281 /*
1282 * Optionally find moves in parents' files.
1283 */
1284 if (opt & PICKAXE_BLAME_MOVE)
1285 for (i = 0, sg = first_scapegoat(revs, commit);
1286 i < num_sg && sg;
1287 sg = sg->next, i++) {
1288 struct origin *porigin = sg_origin[i];
1289 if (!porigin)
1290 continue;
1291 if (find_move_in_parent(sb, origin, porigin))
1292 goto finish;
1293 }
1294
1295 /*
1296 * Optionally find copies from parents' files.
1297 */
1298 if (opt & PICKAXE_BLAME_COPY)
1299 for (i = 0, sg = first_scapegoat(revs, commit);
1300 i < num_sg && sg;
1301 sg = sg->next, i++) {
1302 struct origin *porigin = sg_origin[i];
1303 if (find_copy_in_parent(sb, origin, sg->item,
1304 porigin, opt))
1305 goto finish;
1306 }
1307
1308 finish:
1309 for (i = 0; i < num_sg; i++) {
1310 if (sg_origin[i]) {
1311 drop_origin_blob(sg_origin[i]);
1312 origin_decref(sg_origin[i]);
1313 }
1314 }
1315 drop_origin_blob(origin);
1316 if (sg_buf != sg_origin)
1317 free(sg_origin);
1318 }
1319
1320 /*
1321 * Information on commits, used for output.
1322 */
1323 struct commit_info {
1324 const char *author;
1325 const char *author_mail;
1326 unsigned long author_time;
1327 const char *author_tz;
1328
1329 /* filled only when asked for details */
1330 const char *committer;
1331 const char *committer_mail;
1332 unsigned long committer_time;
1333 const char *committer_tz;
1334
1335 const char *summary;
1336 };
1337
1338 /*
1339 * Parse author/committer line in the commit object buffer
1340 */
1341 static void get_ac_line(const char *inbuf, const char *what,
1342 int person_len, char *person,
1343 int mail_len, char *mail,
1344 unsigned long *time, const char **tz)
1345 {
1346 int len, tzlen, maillen;
1347 char *tmp, *endp, *timepos, *mailpos;
1348
1349 tmp = strstr(inbuf, what);
1350 if (!tmp)
1351 goto error_out;
1352 tmp += strlen(what);
1353 endp = strchr(tmp, '\n');
1354 if (!endp)
1355 len = strlen(tmp);
1356 else
1357 len = endp - tmp;
1358 if (person_len <= len) {
1359 error_out:
1360 /* Ugh */
1361 *tz = "(unknown)";
1362 strcpy(person, *tz);
1363 strcpy(mail, *tz);
1364 *time = 0;
1365 return;
1366 }
1367 memcpy(person, tmp, len);
1368
1369 tmp = person;
1370 tmp += len;
1371 *tmp = 0;
1372 while (person < tmp && *tmp != ' ')
1373 tmp--;
1374 if (tmp <= person)
1375 goto error_out;
1376 *tz = tmp+1;
1377 tzlen = (person+len)-(tmp+1);
1378
1379 *tmp = 0;
1380 while (person < tmp && *tmp != ' ')
1381 tmp--;
1382 if (tmp <= person)
1383 goto error_out;
1384 *time = strtoul(tmp, NULL, 10);
1385 timepos = tmp;
1386
1387 *tmp = 0;
1388 while (person < tmp && !(*tmp == ' ' && tmp[1] == '<'))
1389 tmp--;
1390 if (tmp <= person)
1391 return;
1392 mailpos = tmp + 1;
1393 *tmp = 0;
1394 maillen = timepos - tmp;
1395 memcpy(mail, mailpos, maillen);
1396
1397 if (!mailmap.nr)
1398 return;
1399
1400 /*
1401 * mailmap expansion may make the name longer.
1402 * make room by pushing stuff down.
1403 */
1404 tmp = person + person_len - (tzlen + 1);
1405 memmove(tmp, *tz, tzlen);
1406 tmp[tzlen] = 0;
1407 *tz = tmp;
1408
1409 /*
1410 * Now, convert both name and e-mail using mailmap
1411 */
1412 if (map_user(&mailmap, mail+1, mail_len-1, person, tmp-person-1)) {
1413 /* Add a trailing '>' to email, since map_user returns plain emails
1414 Note: It already has '<', since we replace from mail+1 */
1415 mailpos = memchr(mail, '\0', mail_len);
1416 if (mailpos && mailpos-mail < mail_len - 1) {
1417 *mailpos = '>';
1418 *(mailpos+1) = '\0';
1419 }
1420 }
1421 }
1422
1423 static void get_commit_info(struct commit *commit,
1424 struct commit_info *ret,
1425 int detailed)
1426 {
1427 int len;
1428 const char *subject;
1429 char *reencoded, *message;
1430 static char author_name[1024];
1431 static char author_mail[1024];
1432 static char committer_name[1024];
1433 static char committer_mail[1024];
1434 static char summary_buf[1024];
1435
1436 /*
1437 * We've operated without save_commit_buffer, so
1438 * we now need to populate them for output.
1439 */
1440 if (!commit->buffer) {
1441 enum object_type type;
1442 unsigned long size;
1443 commit->buffer =
1444 read_sha1_file(commit->object.sha1, &type, &size);
1445 if (!commit->buffer)
1446 die("Cannot read commit %s",
1447 sha1_to_hex(commit->object.sha1));
1448 }
1449 reencoded = reencode_commit_message(commit, NULL);
1450 message = reencoded ? reencoded : commit->buffer;
1451 ret->author = author_name;
1452 ret->author_mail = author_mail;
1453 get_ac_line(message, "\nauthor ",
1454 sizeof(author_name), author_name,
1455 sizeof(author_mail), author_mail,
1456 &ret->author_time, &ret->author_tz);
1457
1458 if (!detailed) {
1459 free(reencoded);
1460 return;
1461 }
1462
1463 ret->committer = committer_name;
1464 ret->committer_mail = committer_mail;
1465 get_ac_line(message, "\ncommitter ",
1466 sizeof(committer_name), committer_name,
1467 sizeof(committer_mail), committer_mail,
1468 &ret->committer_time, &ret->committer_tz);
1469
1470 ret->summary = summary_buf;
1471 len = find_commit_subject(message, &subject);
1472 if (len && len < sizeof(summary_buf)) {
1473 memcpy(summary_buf, subject, len);
1474 summary_buf[len] = 0;
1475 } else {
1476 sprintf(summary_buf, "(%s)", sha1_to_hex(commit->object.sha1));
1477 }
1478 free(reencoded);
1479 }
1480
1481 /*
1482 * To allow LF and other nonportable characters in pathnames,
1483 * they are c-style quoted as needed.
1484 */
1485 static void write_filename_info(const char *path)
1486 {
1487 printf("filename ");
1488 write_name_quoted(path, stdout, '\n');
1489 }
1490
1491 /*
1492 * Porcelain/Incremental format wants to show a lot of details per
1493 * commit. Instead of repeating this every line, emit it only once,
1494 * the first time each commit appears in the output (unless the
1495 * user has specifically asked for us to repeat).
1496 */
1497 static int emit_one_suspect_detail(struct origin *suspect, int repeat)
1498 {
1499 struct commit_info ci;
1500
1501 if (!repeat && (suspect->commit->object.flags & METAINFO_SHOWN))
1502 return 0;
1503
1504 suspect->commit->object.flags |= METAINFO_SHOWN;
1505 get_commit_info(suspect->commit, &ci, 1);
1506 printf("author %s\n", ci.author);
1507 printf("author-mail %s\n", ci.author_mail);
1508 printf("author-time %lu\n", ci.author_time);
1509 printf("author-tz %s\n", ci.author_tz);
1510 printf("committer %s\n", ci.committer);
1511 printf("committer-mail %s\n", ci.committer_mail);
1512 printf("committer-time %lu\n", ci.committer_time);
1513 printf("committer-tz %s\n", ci.committer_tz);
1514 printf("summary %s\n", ci.summary);
1515 if (suspect->commit->object.flags & UNINTERESTING)
1516 printf("boundary\n");
1517 if (suspect->previous) {
1518 struct origin *prev = suspect->previous;
1519 printf("previous %s ", sha1_to_hex(prev->commit->object.sha1));
1520 write_name_quoted(prev->path, stdout, '\n');
1521 }
1522 return 1;
1523 }
1524
1525 /*
1526 * The blame_entry is found to be guilty for the range. Mark it
1527 * as such, and show it in incremental output.
1528 */
1529 static void found_guilty_entry(struct blame_entry *ent)
1530 {
1531 if (ent->guilty)
1532 return;
1533 ent->guilty = 1;
1534 if (incremental) {
1535 struct origin *suspect = ent->suspect;
1536
1537 printf("%s %d %d %d\n",
1538 sha1_to_hex(suspect->commit->object.sha1),
1539 ent->s_lno + 1, ent->lno + 1, ent->num_lines);
1540 emit_one_suspect_detail(suspect, 0);
1541 write_filename_info(suspect->path);
1542 maybe_flush_or_die(stdout, "stdout");
1543 }
1544 }
1545
1546 /*
1547 * The main loop -- while the scoreboard has lines whose true origin
1548 * is still unknown, pick one blame_entry, and allow its current
1549 * suspect to pass blames to its parents.
1550 */
1551 static void assign_blame(struct scoreboard *sb, int opt)
1552 {
1553 struct rev_info *revs = sb->revs;
1554
1555 while (1) {
1556 struct blame_entry *ent;
1557 struct commit *commit;
1558 struct origin *suspect = NULL;
1559
1560 /* find one suspect to break down */
1561 for (ent = sb->ent; !suspect && ent; ent = ent->next)
1562 if (!ent->guilty)
1563 suspect = ent->suspect;
1564 if (!suspect)
1565 return; /* all done */
1566
1567 /*
1568 * We will use this suspect later in the loop,
1569 * so hold onto it in the meantime.
1570 */
1571 origin_incref(suspect);
1572 commit = suspect->commit;
1573 if (!commit->object.parsed)
1574 parse_commit(commit);
1575 if (reverse ||
1576 (!(commit->object.flags & UNINTERESTING) &&
1577 !(revs->max_age != -1 && commit->date < revs->max_age)))
1578 pass_blame(sb, suspect, opt);
1579 else {
1580 commit->object.flags |= UNINTERESTING;
1581 if (commit->object.parsed)
1582 mark_parents_uninteresting(commit);
1583 }
1584 /* treat root commit as boundary */
1585 if (!commit->parents && !show_root)
1586 commit->object.flags |= UNINTERESTING;
1587
1588 /* Take responsibility for the remaining entries */
1589 for (ent = sb->ent; ent; ent = ent->next)
1590 if (same_suspect(ent->suspect, suspect))
1591 found_guilty_entry(ent);
1592 origin_decref(suspect);
1593
1594 if (DEBUG) /* sanity */
1595 sanity_check_refcnt(sb);
1596 }
1597 }
1598
1599 static const char *format_time(unsigned long time, const char *tz_str,
1600 int show_raw_time)
1601 {
1602 static char time_buf[128];
1603 const char *time_str;
1604 int time_len;
1605 int tz;
1606
1607 if (show_raw_time) {
1608 snprintf(time_buf, sizeof(time_buf), "%lu %s", time, tz_str);
1609 }
1610 else {
1611 tz = atoi(tz_str);
1612 time_str = show_date(time, tz, blame_date_mode);
1613 time_len = strlen(time_str);
1614 memcpy(time_buf, time_str, time_len);
1615 memset(time_buf + time_len, ' ', blame_date_width - time_len);
1616 }
1617 return time_buf;
1618 }
1619
1620 #define OUTPUT_ANNOTATE_COMPAT 001
1621 #define OUTPUT_LONG_OBJECT_NAME 002
1622 #define OUTPUT_RAW_TIMESTAMP 004
1623 #define OUTPUT_PORCELAIN 010
1624 #define OUTPUT_SHOW_NAME 020
1625 #define OUTPUT_SHOW_NUMBER 040
1626 #define OUTPUT_SHOW_SCORE 0100
1627 #define OUTPUT_NO_AUTHOR 0200
1628 #define OUTPUT_SHOW_EMAIL 0400
1629 #define OUTPUT_LINE_PORCELAIN 01000
1630
1631 static void emit_porcelain_details(struct origin *suspect, int repeat)
1632 {
1633 if (emit_one_suspect_detail(suspect, repeat) ||
1634 (suspect->commit->object.flags & MORE_THAN_ONE_PATH))
1635 write_filename_info(suspect->path);
1636 }
1637
1638 static void emit_porcelain(struct scoreboard *sb, struct blame_entry *ent,
1639 int opt)
1640 {
1641 int repeat = opt & OUTPUT_LINE_PORCELAIN;
1642 int cnt;
1643 const char *cp;
1644 struct origin *suspect = ent->suspect;
1645 char hex[41];
1646
1647 strcpy(hex, sha1_to_hex(suspect->commit->object.sha1));
1648 printf("%s%c%d %d %d\n",
1649 hex,
1650 ent->guilty ? ' ' : '*', /* purely for debugging */
1651 ent->s_lno + 1,
1652 ent->lno + 1,
1653 ent->num_lines);
1654 emit_porcelain_details(suspect, repeat);
1655
1656 cp = nth_line(sb, ent->lno);
1657 for (cnt = 0; cnt < ent->num_lines; cnt++) {
1658 char ch;
1659 if (cnt) {
1660 printf("%s %d %d\n", hex,
1661 ent->s_lno + 1 + cnt,
1662 ent->lno + 1 + cnt);
1663 if (repeat)
1664 emit_porcelain_details(suspect, 1);
1665 }
1666 putchar('\t');
1667 do {
1668 ch = *cp++;
1669 putchar(ch);
1670 } while (ch != '\n' &&
1671 cp < sb->final_buf + sb->final_buf_size);
1672 }
1673
1674 if (sb->final_buf_size && cp[-1] != '\n')
1675 putchar('\n');
1676 }
1677
1678 static void emit_other(struct scoreboard *sb, struct blame_entry *ent, int opt)
1679 {
1680 int cnt;
1681 const char *cp;
1682 struct origin *suspect = ent->suspect;
1683 struct commit_info ci;
1684 char hex[41];
1685 int show_raw_time = !!(opt & OUTPUT_RAW_TIMESTAMP);
1686
1687 get_commit_info(suspect->commit, &ci, 1);
1688 strcpy(hex, sha1_to_hex(suspect->commit->object.sha1));
1689
1690 cp = nth_line(sb, ent->lno);
1691 for (cnt = 0; cnt < ent->num_lines; cnt++) {
1692 char ch;
1693 int length = (opt & OUTPUT_LONG_OBJECT_NAME) ? 40 : abbrev;
1694
1695 if (suspect->commit->object.flags & UNINTERESTING) {
1696 if (blank_boundary)
1697 memset(hex, ' ', length);
1698 else if (!(opt & OUTPUT_ANNOTATE_COMPAT)) {
1699 length--;
1700 putchar('^');
1701 }
1702 }
1703
1704 printf("%.*s", length, hex);
1705 if (opt & OUTPUT_ANNOTATE_COMPAT) {
1706 const char *name;
1707 if (opt & OUTPUT_SHOW_EMAIL)
1708 name = ci.author_mail;
1709 else
1710 name = ci.author;
1711 printf("\t(%10s\t%10s\t%d)", name,
1712 format_time(ci.author_time, ci.author_tz,
1713 show_raw_time),
1714 ent->lno + 1 + cnt);
1715 } else {
1716 if (opt & OUTPUT_SHOW_SCORE)
1717 printf(" %*d %02d",
1718 max_score_digits, ent->score,
1719 ent->suspect->refcnt);
1720 if (opt & OUTPUT_SHOW_NAME)
1721 printf(" %-*.*s", longest_file, longest_file,
1722 suspect->path);
1723 if (opt & OUTPUT_SHOW_NUMBER)
1724 printf(" %*d", max_orig_digits,
1725 ent->s_lno + 1 + cnt);
1726
1727 if (!(opt & OUTPUT_NO_AUTHOR)) {
1728 const char *name;
1729 int pad;
1730 if (opt & OUTPUT_SHOW_EMAIL)
1731 name = ci.author_mail;
1732 else
1733 name = ci.author;
1734 pad = longest_author - utf8_strwidth(name);
1735 printf(" (%s%*s %10s",
1736 name, pad, "",
1737 format_time(ci.author_time,
1738 ci.author_tz,
1739 show_raw_time));
1740 }
1741 printf(" %*d) ",
1742 max_digits, ent->lno + 1 + cnt);
1743 }
1744 do {
1745 ch = *cp++;
1746 putchar(ch);
1747 } while (ch != '\n' &&
1748 cp < sb->final_buf + sb->final_buf_size);
1749 }
1750
1751 if (sb->final_buf_size && cp[-1] != '\n')
1752 putchar('\n');
1753 }
1754
1755 static void output(struct scoreboard *sb, int option)
1756 {
1757 struct blame_entry *ent;
1758
1759 if (option & OUTPUT_PORCELAIN) {
1760 for (ent = sb->ent; ent; ent = ent->next) {
1761 struct blame_entry *oth;
1762 struct origin *suspect = ent->suspect;
1763 struct commit *commit = suspect->commit;
1764 if (commit->object.flags & MORE_THAN_ONE_PATH)
1765 continue;
1766 for (oth = ent->next; oth; oth = oth->next) {
1767 if ((oth->suspect->commit != commit) ||
1768 !strcmp(oth->suspect->path, suspect->path))
1769 continue;
1770 commit->object.flags |= MORE_THAN_ONE_PATH;
1771 break;
1772 }
1773 }
1774 }
1775
1776 for (ent = sb->ent; ent; ent = ent->next) {
1777 if (option & OUTPUT_PORCELAIN)
1778 emit_porcelain(sb, ent, option);
1779 else {
1780 emit_other(sb, ent, option);
1781 }
1782 }
1783 }
1784
1785 /*
1786 * To allow quick access to the contents of nth line in the
1787 * final image, prepare an index in the scoreboard.
1788 */
1789 static int prepare_lines(struct scoreboard *sb)
1790 {
1791 const char *buf = sb->final_buf;
1792 unsigned long len = sb->final_buf_size;
1793 int num = 0, incomplete = 0, bol = 1;
1794
1795 if (len && buf[len-1] != '\n')
1796 incomplete++; /* incomplete line at the end */
1797 while (len--) {
1798 if (bol) {
1799 sb->lineno = xrealloc(sb->lineno,
1800 sizeof(int *) * (num + 1));
1801 sb->lineno[num] = buf - sb->final_buf;
1802 bol = 0;
1803 }
1804 if (*buf++ == '\n') {
1805 num++;
1806 bol = 1;
1807 }
1808 }
1809 sb->lineno = xrealloc(sb->lineno,
1810 sizeof(int *) * (num + incomplete + 1));
1811 sb->lineno[num + incomplete] = buf - sb->final_buf;
1812 sb->num_lines = num + incomplete;
1813 return sb->num_lines;
1814 }
1815
1816 /*
1817 * Add phony grafts for use with -S; this is primarily to
1818 * support git's cvsserver that wants to give a linear history
1819 * to its clients.
1820 */
1821 static int read_ancestry(const char *graft_file)
1822 {
1823 FILE *fp = fopen(graft_file, "r");
1824 char buf[1024];
1825 if (!fp)
1826 return -1;
1827 while (fgets(buf, sizeof(buf), fp)) {
1828 /* The format is just "Commit Parent1 Parent2 ...\n" */
1829 int len = strlen(buf);
1830 struct commit_graft *graft = read_graft_line(buf, len);
1831 if (graft)
1832 register_commit_graft(graft, 0);
1833 }
1834 fclose(fp);
1835 return 0;
1836 }
1837
1838 static int update_auto_abbrev(int auto_abbrev, struct origin *suspect)
1839 {
1840 const char *uniq = find_unique_abbrev(suspect->commit->object.sha1,
1841 auto_abbrev);
1842 int len = strlen(uniq);
1843 if (auto_abbrev < len)
1844 return len;
1845 return auto_abbrev;
1846 }
1847
1848 /*
1849 * How many columns do we need to show line numbers, authors,
1850 * and filenames?
1851 */
1852 static void find_alignment(struct scoreboard *sb, int *option)
1853 {
1854 int longest_src_lines = 0;
1855 int longest_dst_lines = 0;
1856 unsigned largest_score = 0;
1857 struct blame_entry *e;
1858 int compute_auto_abbrev = (abbrev < 0);
1859 int auto_abbrev = default_abbrev;
1860
1861 for (e = sb->ent; e; e = e->next) {
1862 struct origin *suspect = e->suspect;
1863 struct commit_info ci;
1864 int num;
1865
1866 if (compute_auto_abbrev)
1867 auto_abbrev = update_auto_abbrev(auto_abbrev, suspect);
1868 if (strcmp(suspect->path, sb->path))
1869 *option |= OUTPUT_SHOW_NAME;
1870 num = strlen(suspect->path);
1871 if (longest_file < num)
1872 longest_file = num;
1873 if (!(suspect->commit->object.flags & METAINFO_SHOWN)) {
1874 suspect->commit->object.flags |= METAINFO_SHOWN;
1875 get_commit_info(suspect->commit, &ci, 1);
1876 if (*option & OUTPUT_SHOW_EMAIL)
1877 num = utf8_strwidth(ci.author_mail);
1878 else
1879 num = utf8_strwidth(ci.author);
1880 if (longest_author < num)
1881 longest_author = num;
1882 }
1883 num = e->s_lno + e->num_lines;
1884 if (longest_src_lines < num)
1885 longest_src_lines = num;
1886 num = e->lno + e->num_lines;
1887 if (longest_dst_lines < num)
1888 longest_dst_lines = num;
1889 if (largest_score < ent_score(sb, e))
1890 largest_score = ent_score(sb, e);
1891 }
1892 max_orig_digits = decimal_width(longest_src_lines);
1893 max_digits = decimal_width(longest_dst_lines);
1894 max_score_digits = decimal_width(largest_score);
1895
1896 if (compute_auto_abbrev)
1897 /* one more abbrev length is needed for the boundary commit */
1898 abbrev = auto_abbrev + 1;
1899 }
1900
1901 /*
1902 * For debugging -- origin is refcounted, and this asserts that
1903 * we do not underflow.
1904 */
1905 static void sanity_check_refcnt(struct scoreboard *sb)
1906 {
1907 int baa = 0;
1908 struct blame_entry *ent;
1909
1910 for (ent = sb->ent; ent; ent = ent->next) {
1911 /* Nobody should have zero or negative refcnt */
1912 if (ent->suspect->refcnt <= 0) {
1913 fprintf(stderr, "%s in %s has negative refcnt %d\n",
1914 ent->suspect->path,
1915 sha1_to_hex(ent->suspect->commit->object.sha1),
1916 ent->suspect->refcnt);
1917 baa = 1;
1918 }
1919 }
1920 if (baa) {
1921 int opt = 0160;
1922 find_alignment(sb, &opt);
1923 output(sb, opt);
1924 die("Baa %d!", baa);
1925 }
1926 }
1927
1928 /*
1929 * Used for the command line parsing; check if the path exists
1930 * in the working tree.
1931 */
1932 static int has_string_in_work_tree(const char *path)
1933 {
1934 struct stat st;
1935 return !lstat(path, &st);
1936 }
1937
1938 static unsigned parse_score(const char *arg)
1939 {
1940 char *end;
1941 unsigned long score = strtoul(arg, &end, 10);
1942 if (*end)
1943 return 0;
1944 return score;
1945 }
1946
1947 static const char *add_prefix(const char *prefix, const char *path)
1948 {
1949 return prefix_path(prefix, prefix ? strlen(prefix) : 0, path);
1950 }
1951
1952 /*
1953 * Parsing of (comma separated) one item in the -L option
1954 */
1955 static const char *parse_loc(const char *spec,
1956 struct scoreboard *sb, long lno,
1957 long begin, long *ret)
1958 {
1959 char *term;
1960 const char *line;
1961 long num;
1962 int reg_error;
1963 regex_t regexp;
1964 regmatch_t match[1];
1965
1966 /* Allow "-L <something>,+20" to mean starting at <something>
1967 * for 20 lines, or "-L <something>,-5" for 5 lines ending at
1968 * <something>.
1969 */
1970 if (1 < begin && (spec[0] == '+' || spec[0] == '-')) {
1971 num = strtol(spec + 1, &term, 10);
1972 if (term != spec + 1) {
1973 if (spec[0] == '-')
1974 num = 0 - num;
1975 if (0 < num)
1976 *ret = begin + num - 2;
1977 else if (!num)
1978 *ret = begin;
1979 else
1980 *ret = begin + num;
1981 return term;
1982 }
1983 return spec;
1984 }
1985 num = strtol(spec, &term, 10);
1986 if (term != spec) {
1987 *ret = num;
1988 return term;
1989 }
1990 if (spec[0] != '/')
1991 return spec;
1992
1993 /* it could be a regexp of form /.../ */
1994 for (term = (char *) spec + 1; *term && *term != '/'; term++) {
1995 if (*term == '\\')
1996 term++;
1997 }
1998 if (*term != '/')
1999 return spec;
2000
2001 /* try [spec+1 .. term-1] as regexp */
2002 *term = 0;
2003 begin--; /* input is in human terms */
2004 line = nth_line(sb, begin);
2005
2006 if (!(reg_error = regcomp(&regexp, spec + 1, REG_NEWLINE)) &&
2007 !(reg_error = regexec(&regexp, line, 1, match, 0))) {
2008 const char *cp = line + match[0].rm_so;
2009 const char *nline;
2010
2011 while (begin++ < lno) {
2012 nline = nth_line(sb, begin);
2013 if (line <= cp && cp < nline)
2014 break;
2015 line = nline;
2016 }
2017 *ret = begin;
2018 regfree(&regexp);
2019 *term++ = '/';
2020 return term;
2021 }
2022 else {
2023 char errbuf[1024];
2024 regerror(reg_error, &regexp, errbuf, 1024);
2025 die("-L parameter '%s': %s", spec + 1, errbuf);
2026 }
2027 }
2028
2029 /*
2030 * Parsing of -L option
2031 */
2032 static void prepare_blame_range(struct scoreboard *sb,
2033 const char *bottomtop,
2034 long lno,
2035 long *bottom, long *top)
2036 {
2037 const char *term;
2038
2039 term = parse_loc(bottomtop, sb, lno, 1, bottom);
2040 if (*term == ',') {
2041 term = parse_loc(term + 1, sb, lno, *bottom + 1, top);
2042 if (*term)
2043 usage(blame_usage);
2044 }
2045 if (*term)
2046 usage(blame_usage);
2047 }
2048
2049 static int git_blame_config(const char *var, const char *value, void *cb)
2050 {
2051 if (!strcmp(var, "blame.showroot")) {
2052 show_root = git_config_bool(var, value);
2053 return 0;
2054 }
2055 if (!strcmp(var, "blame.blankboundary")) {
2056 blank_boundary = git_config_bool(var, value);
2057 return 0;
2058 }
2059 if (!strcmp(var, "blame.date")) {
2060 if (!value)
2061 return config_error_nonbool(var);
2062 blame_date_mode = parse_date_format(value);
2063 return 0;
2064 }
2065
2066 if (userdiff_config(var, value) < 0)
2067 return -1;
2068
2069 return git_default_config(var, value, cb);
2070 }
2071
2072 static void verify_working_tree_path(struct commit *work_tree, const char *path)
2073 {
2074 struct commit_list *parents;
2075
2076 for (parents = work_tree->parents; parents; parents = parents->next) {
2077 const unsigned char *commit_sha1 = parents->item->object.sha1;
2078 unsigned char blob_sha1[20];
2079 unsigned mode;
2080
2081 if (!get_tree_entry(commit_sha1, path, blob_sha1, &mode) &&
2082 sha1_object_info(blob_sha1, NULL) == OBJ_BLOB)
2083 return;
2084 }
2085 die("no such path '%s' in HEAD", path);
2086 }
2087
2088 static struct commit_list **append_parent(struct commit_list **tail, const unsigned char *sha1)
2089 {
2090 struct commit *parent;
2091
2092 parent = lookup_commit_reference(sha1);
2093 if (!parent)
2094 die("no such commit %s", sha1_to_hex(sha1));
2095 return &commit_list_insert(parent, tail)->next;
2096 }
2097
2098 static void append_merge_parents(struct commit_list **tail)
2099 {
2100 int merge_head;
2101 const char *merge_head_file = git_path("MERGE_HEAD");
2102 struct strbuf line = STRBUF_INIT;
2103
2104 merge_head = open(merge_head_file, O_RDONLY);
2105 if (merge_head < 0) {
2106 if (errno == ENOENT)
2107 return;
2108 die("cannot open '%s' for reading", merge_head_file);
2109 }
2110
2111 while (!strbuf_getwholeline_fd(&line, merge_head, '\n')) {
2112 unsigned char sha1[20];
2113 if (line.len < 40 || get_sha1_hex(line.buf, sha1))
2114 die("unknown line in '%s': %s", merge_head_file, line.buf);
2115 tail = append_parent(tail, sha1);
2116 }
2117 close(merge_head);
2118 strbuf_release(&line);
2119 }
2120
2121 /*
2122 * Prepare a dummy commit that represents the work tree (or staged) item.
2123 * Note that annotating work tree item never works in the reverse.
2124 */
2125 static struct commit *fake_working_tree_commit(struct diff_options *opt,
2126 const char *path,
2127 const char *contents_from)
2128 {
2129 struct commit *commit;
2130 struct origin *origin;
2131 struct commit_list **parent_tail, *parent;
2132 unsigned char head_sha1[20];
2133 struct strbuf buf = STRBUF_INIT;
2134 const char *ident;
2135 time_t now;
2136 int size, len;
2137 struct cache_entry *ce;
2138 unsigned mode;
2139 struct strbuf msg = STRBUF_INIT;
2140
2141 time(&now);
2142 commit = xcalloc(1, sizeof(*commit));
2143 commit->object.parsed = 1;
2144 commit->date = now;
2145 commit->object.type = OBJ_COMMIT;
2146 parent_tail = &commit->parents;
2147
2148 if (!resolve_ref_unsafe("HEAD", head_sha1, 1, NULL))
2149 die("no such ref: HEAD");
2150
2151 parent_tail = append_parent(parent_tail, head_sha1);
2152 append_merge_parents(parent_tail);
2153 verify_working_tree_path(commit, path);
2154
2155 origin = make_origin(commit, path);
2156
2157 ident = fmt_ident("Not Committed Yet", "not.committed.yet", NULL, 0);
2158 strbuf_addstr(&msg, "tree 0000000000000000000000000000000000000000\n");
2159 for (parent = commit->parents; parent; parent = parent->next)
2160 strbuf_addf(&msg, "parent %s\n",
2161 sha1_to_hex(parent->item->object.sha1));
2162 strbuf_addf(&msg,
2163 "author %s\n"
2164 "committer %s\n\n"
2165 "Version of %s from %s\n",
2166 ident, ident, path,
2167 (!contents_from ? path :
2168 (!strcmp(contents_from, "-") ? "standard input" : contents_from)));
2169 commit->buffer = strbuf_detach(&msg, NULL);
2170
2171 if (!contents_from || strcmp("-", contents_from)) {
2172 struct stat st;
2173 const char *read_from;
2174 char *buf_ptr;
2175 unsigned long buf_len;
2176
2177 if (contents_from) {
2178 if (stat(contents_from, &st) < 0)
2179 die_errno("Cannot stat '%s'", contents_from);
2180 read_from = contents_from;
2181 }
2182 else {
2183 if (lstat(path, &st) < 0)
2184 die_errno("Cannot lstat '%s'", path);
2185 read_from = path;
2186 }
2187 mode = canon_mode(st.st_mode);
2188
2189 switch (st.st_mode & S_IFMT) {
2190 case S_IFREG:
2191 if (DIFF_OPT_TST(opt, ALLOW_TEXTCONV) &&
2192 textconv_object(read_from, mode, null_sha1, 0, &buf_ptr, &buf_len))
2193 strbuf_attach(&buf, buf_ptr, buf_len, buf_len + 1);
2194 else if (strbuf_read_file(&buf, read_from, st.st_size) != st.st_size)
2195 die_errno("cannot open or read '%s'", read_from);
2196 break;
2197 case S_IFLNK:
2198 if (strbuf_readlink(&buf, read_from, st.st_size) < 0)
2199 die_errno("cannot readlink '%s'", read_from);
2200 break;
2201 default:
2202 die("unsupported file type %s", read_from);
2203 }
2204 }
2205 else {
2206 /* Reading from stdin */
2207 mode = 0;
2208 if (strbuf_read(&buf, 0, 0) < 0)
2209 die_errno("failed to read from stdin");
2210 }
2211 convert_to_git(path, buf.buf, buf.len, &buf, 0);
2212 origin->file.ptr = buf.buf;
2213 origin->file.size = buf.len;
2214 pretend_sha1_file(buf.buf, buf.len, OBJ_BLOB, origin->blob_sha1);
2215 commit->util = origin;
2216
2217 /*
2218 * Read the current index, replace the path entry with
2219 * origin->blob_sha1 without mucking with its mode or type
2220 * bits; we are not going to write this index out -- we just
2221 * want to run "diff-index --cached".
2222 */
2223 discard_cache();
2224 read_cache();
2225
2226 len = strlen(path);
2227 if (!mode) {
2228 int pos = cache_name_pos(path, len);
2229 if (0 <= pos)
2230 mode = active_cache[pos]->ce_mode;
2231 else
2232 /* Let's not bother reading from HEAD tree */
2233 mode = S_IFREG | 0644;
2234 }
2235 size = cache_entry_size(len);
2236 ce = xcalloc(1, size);
2237 hashcpy(ce->sha1, origin->blob_sha1);
2238 memcpy(ce->name, path, len);
2239 ce->ce_flags = create_ce_flags(0);
2240 ce->ce_namelen = len;
2241 ce->ce_mode = create_ce_mode(mode);
2242 add_cache_entry(ce, ADD_CACHE_OK_TO_ADD|ADD_CACHE_OK_TO_REPLACE);
2243
2244 /*
2245 * We are not going to write this out, so this does not matter
2246 * right now, but someday we might optimize diff-index --cached
2247 * with cache-tree information.
2248 */
2249 cache_tree_invalidate_path(active_cache_tree, path);
2250
2251 return commit;
2252 }
2253
2254 static const char *prepare_final(struct scoreboard *sb)
2255 {
2256 int i;
2257 const char *final_commit_name = NULL;
2258 struct rev_info *revs = sb->revs;
2259
2260 /*
2261 * There must be one and only one positive commit in the
2262 * revs->pending array.
2263 */
2264 for (i = 0; i < revs->pending.nr; i++) {
2265 struct object *obj = revs->pending.objects[i].item;
2266 if (obj->flags & UNINTERESTING)
2267 continue;
2268 while (obj->type == OBJ_TAG)
2269 obj = deref_tag(obj, NULL, 0);
2270 if (obj->type != OBJ_COMMIT)
2271 die("Non commit %s?", revs->pending.objects[i].name);
2272 if (sb->final)
2273 die("More than one commit to dig from %s and %s?",
2274 revs->pending.objects[i].name,
2275 final_commit_name);
2276 sb->final = (struct commit *) obj;
2277 final_commit_name = revs->pending.objects[i].name;
2278 }
2279 return final_commit_name;
2280 }
2281
2282 static const char *prepare_initial(struct scoreboard *sb)
2283 {
2284 int i;
2285 const char *final_commit_name = NULL;
2286 struct rev_info *revs = sb->revs;
2287
2288 /*
2289 * There must be one and only one negative commit, and it must be
2290 * the boundary.
2291 */
2292 for (i = 0; i < revs->pending.nr; i++) {
2293 struct object *obj = revs->pending.objects[i].item;
2294 if (!(obj->flags & UNINTERESTING))
2295 continue;
2296 while (obj->type == OBJ_TAG)
2297 obj = deref_tag(obj, NULL, 0);
2298 if (obj->type != OBJ_COMMIT)
2299 die("Non commit %s?", revs->pending.objects[i].name);
2300 if (sb->final)
2301 die("More than one commit to dig down to %s and %s?",
2302 revs->pending.objects[i].name,
2303 final_commit_name);
2304 sb->final = (struct commit *) obj;
2305 final_commit_name = revs->pending.objects[i].name;
2306 }
2307 if (!final_commit_name)
2308 die("No commit to dig down to?");
2309 return final_commit_name;
2310 }
2311
2312 static int blame_copy_callback(const struct option *option, const char *arg, int unset)
2313 {
2314 int *opt = option->value;
2315
2316 /*
2317 * -C enables copy from removed files;
2318 * -C -C enables copy from existing files, but only
2319 * when blaming a new file;
2320 * -C -C -C enables copy from existing files for
2321 * everybody
2322 */
2323 if (*opt & PICKAXE_BLAME_COPY_HARDER)
2324 *opt |= PICKAXE_BLAME_COPY_HARDEST;
2325 if (*opt & PICKAXE_BLAME_COPY)
2326 *opt |= PICKAXE_BLAME_COPY_HARDER;
2327 *opt |= PICKAXE_BLAME_COPY | PICKAXE_BLAME_MOVE;
2328
2329 if (arg)
2330 blame_copy_score = parse_score(arg);
2331 return 0;
2332 }
2333
2334 static int blame_move_callback(const struct option *option, const char *arg, int unset)
2335 {
2336 int *opt = option->value;
2337
2338 *opt |= PICKAXE_BLAME_MOVE;
2339
2340 if (arg)
2341 blame_move_score = parse_score(arg);
2342 return 0;
2343 }
2344
2345 static int blame_bottomtop_callback(const struct option *option, const char *arg, int unset)
2346 {
2347 const char **bottomtop = option->value;
2348 if (!arg)
2349 return -1;
2350 if (*bottomtop)
2351 die("More than one '-L n,m' option given");
2352 *bottomtop = arg;
2353 return 0;
2354 }
2355
2356 int cmd_blame(int argc, const char **argv, const char *prefix)
2357 {
2358 struct rev_info revs;
2359 const char *path;
2360 struct scoreboard sb;
2361 struct origin *o;
2362 struct blame_entry *ent;
2363 long dashdash_pos, bottom, top, lno;
2364 const char *final_commit_name = NULL;
2365 enum object_type type;
2366
2367 static const char *bottomtop = NULL;
2368 static int output_option = 0, opt = 0;
2369 static int show_stats = 0;
2370 static const char *revs_file = NULL;
2371 static const char *contents_from = NULL;
2372 static const struct option options[] = {
2373 OPT_BOOLEAN(0, "incremental", &incremental, "Show blame entries as we find them, incrementally"),
2374 OPT_BOOLEAN('b', NULL, &blank_boundary, "Show blank SHA-1 for boundary commits (Default: off)"),
2375 OPT_BOOLEAN(0, "root", &show_root, "Do not treat root commits as boundaries (Default: off)"),
2376 OPT_BOOLEAN(0, "show-stats", &show_stats, "Show work cost statistics"),
2377 OPT_BIT(0, "score-debug", &output_option, "Show output score for blame entries", OUTPUT_SHOW_SCORE),
2378 OPT_BIT('f', "show-name", &output_option, "Show original filename (Default: auto)", OUTPUT_SHOW_NAME),
2379 OPT_BIT('n', "show-number", &output_option, "Show original linenumber (Default: off)", OUTPUT_SHOW_NUMBER),
2380 OPT_BIT('p', "porcelain", &output_option, "Show in a format designed for machine consumption", OUTPUT_PORCELAIN),
2381 OPT_BIT(0, "line-porcelain", &output_option, "Show porcelain format with per-line commit information", OUTPUT_PORCELAIN|OUTPUT_LINE_PORCELAIN),
2382 OPT_BIT('c', NULL, &output_option, "Use the same output mode as git-annotate (Default: off)", OUTPUT_ANNOTATE_COMPAT),
2383 OPT_BIT('t', NULL, &output_option, "Show raw timestamp (Default: off)", OUTPUT_RAW_TIMESTAMP),
2384 OPT_BIT('l', NULL, &output_option, "Show long commit SHA1 (Default: off)", OUTPUT_LONG_OBJECT_NAME),
2385 OPT_BIT('s', NULL, &output_option, "Suppress author name and timestamp (Default: off)", OUTPUT_NO_AUTHOR),
2386 OPT_BIT('e', "show-email", &output_option, "Show author email instead of name (Default: off)", OUTPUT_SHOW_EMAIL),
2387 OPT_BIT('w', NULL, &xdl_opts, "Ignore whitespace differences", XDF_IGNORE_WHITESPACE),
2388 OPT_BIT(0, "minimal", &xdl_opts, "Spend extra cycles to find better match", XDF_NEED_MINIMAL),
2389 OPT_STRING('S', NULL, &revs_file, "file", "Use revisions from <file> instead of calling git-rev-list"),
2390 OPT_STRING(0, "contents", &contents_from, "file", "Use <file>'s contents as the final image"),
2391 { OPTION_CALLBACK, 'C', NULL, &opt, "score", "Find line copies within and across files", PARSE_OPT_OPTARG, blame_copy_callback },
2392 { OPTION_CALLBACK, 'M', NULL, &opt, "score", "Find line movements within and across files", PARSE_OPT_OPTARG, blame_move_callback },
2393 OPT_CALLBACK('L', NULL, &bottomtop, "n,m", "Process only line range n,m, counting from 1", blame_bottomtop_callback),
2394 OPT__ABBREV(&abbrev),
2395 OPT_END()
2396 };
2397
2398 struct parse_opt_ctx_t ctx;
2399 int cmd_is_annotate = !strcmp(argv[0], "annotate");
2400
2401 git_config(git_blame_config, NULL);
2402 init_revisions(&revs, NULL);
2403 revs.date_mode = blame_date_mode;
2404 DIFF_OPT_SET(&revs.diffopt, ALLOW_TEXTCONV);
2405
2406 save_commit_buffer = 0;
2407 dashdash_pos = 0;
2408
2409 parse_options_start(&ctx, argc, argv, prefix, options,
2410 PARSE_OPT_KEEP_DASHDASH | PARSE_OPT_KEEP_ARGV0);
2411 for (;;) {
2412 switch (parse_options_step(&ctx, options, blame_opt_usage)) {
2413 case PARSE_OPT_HELP:
2414 exit(129);
2415 case PARSE_OPT_DONE:
2416 if (ctx.argv[0])
2417 dashdash_pos = ctx.cpidx;
2418 goto parse_done;
2419 }
2420
2421 if (!strcmp(ctx.argv[0], "--reverse")) {
2422 ctx.argv[0] = "--children";
2423 reverse = 1;
2424 }
2425 parse_revision_opt(&revs, &ctx, options, blame_opt_usage);
2426 }
2427 parse_done:
2428 argc = parse_options_end(&ctx);
2429
2430 if (0 < abbrev)
2431 /* one more abbrev length is needed for the boundary commit */
2432 abbrev++;
2433
2434 if (revs_file && read_ancestry(revs_file))
2435 die_errno("reading graft file '%s' failed", revs_file);
2436
2437 if (cmd_is_annotate) {
2438 output_option |= OUTPUT_ANNOTATE_COMPAT;
2439 blame_date_mode = DATE_ISO8601;
2440 } else {
2441 blame_date_mode = revs.date_mode;
2442 }
2443
2444 /* The maximum width used to show the dates */
2445 switch (blame_date_mode) {
2446 case DATE_RFC2822:
2447 blame_date_width = sizeof("Thu, 19 Oct 2006 16:00:04 -0700");
2448 break;
2449 case DATE_ISO8601:
2450 blame_date_width = sizeof("2006-10-19 16:00:04 -0700");
2451 break;
2452 case DATE_RAW:
2453 blame_date_width = sizeof("1161298804 -0700");
2454 break;
2455 case DATE_SHORT:
2456 blame_date_width = sizeof("2006-10-19");
2457 break;
2458 case DATE_RELATIVE:
2459 /* "normal" is used as the fallback for "relative" */
2460 case DATE_LOCAL:
2461 case DATE_NORMAL:
2462 blame_date_width = sizeof("Thu Oct 19 16:00:04 2006 -0700");
2463 break;
2464 }
2465 blame_date_width -= 1; /* strip the null */
2466
2467 if (DIFF_OPT_TST(&revs.diffopt, FIND_COPIES_HARDER))
2468 opt |= (PICKAXE_BLAME_COPY | PICKAXE_BLAME_MOVE |
2469 PICKAXE_BLAME_COPY_HARDER);
2470
2471 if (!blame_move_score)
2472 blame_move_score = BLAME_DEFAULT_MOVE_SCORE;
2473 if (!blame_copy_score)
2474 blame_copy_score = BLAME_DEFAULT_COPY_SCORE;
2475
2476 /*
2477 * We have collected options unknown to us in argv[1..unk]
2478 * which are to be passed to revision machinery if we are
2479 * going to do the "bottom" processing.
2480 *
2481 * The remaining are:
2482 *
2483 * (1) if dashdash_pos != 0, it is either
2484 * "blame [revisions] -- <path>" or
2485 * "blame -- <path> <rev>"
2486 *
2487 * (2) otherwise, it is one of the two:
2488 * "blame [revisions] <path>"
2489 * "blame <path> <rev>"
2490 *
2491 * Note that we must strip out <path> from the arguments: we do not
2492 * want the path pruning but we may want "bottom" processing.
2493 */
2494 if (dashdash_pos) {
2495 switch (argc - dashdash_pos - 1) {
2496 case 2: /* (1b) */
2497 if (argc != 4)
2498 usage_with_options(blame_opt_usage, options);
2499 /* reorder for the new way: <rev> -- <path> */
2500 argv[1] = argv[3];
2501 argv[3] = argv[2];
2502 argv[2] = "--";
2503 /* FALLTHROUGH */
2504 case 1: /* (1a) */
2505 path = add_prefix(prefix, argv[--argc]);
2506 argv[argc] = NULL;
2507 break;
2508 default:
2509 usage_with_options(blame_opt_usage, options);
2510 }
2511 } else {
2512 if (argc < 2)
2513 usage_with_options(blame_opt_usage, options);
2514 path = add_prefix(prefix, argv[argc - 1]);
2515 if (argc == 3 && !has_string_in_work_tree(path)) { /* (2b) */
2516 path = add_prefix(prefix, argv[1]);
2517 argv[1] = argv[2];
2518 }
2519 argv[argc - 1] = "--";
2520
2521 setup_work_tree();
2522 if (!has_string_in_work_tree(path))
2523 die_errno("cannot stat path '%s'", path);
2524 }
2525
2526 revs.disable_stdin = 1;
2527 setup_revisions(argc, argv, &revs, NULL);
2528 memset(&sb, 0, sizeof(sb));
2529
2530 sb.revs = &revs;
2531 if (!reverse)
2532 final_commit_name = prepare_final(&sb);
2533 else if (contents_from)
2534 die("--contents and --children do not blend well.");
2535 else
2536 final_commit_name = prepare_initial(&sb);
2537
2538 if (!sb.final) {
2539 /*
2540 * "--not A B -- path" without anything positive;
2541 * do not default to HEAD, but use the working tree
2542 * or "--contents".
2543 */
2544 setup_work_tree();
2545 sb.final = fake_working_tree_commit(&sb.revs->diffopt,
2546 path, contents_from);
2547 add_pending_object(&revs, &(sb.final->object), ":");
2548 }
2549 else if (contents_from)
2550 die("Cannot use --contents with final commit object name");
2551
2552 /*
2553 * If we have bottom, this will mark the ancestors of the
2554 * bottom commits we would reach while traversing as
2555 * uninteresting.
2556 */
2557 if (prepare_revision_walk(&revs))
2558 die("revision walk setup failed");
2559
2560 if (is_null_sha1(sb.final->object.sha1)) {
2561 char *buf;
2562 o = sb.final->util;
2563 buf = xmalloc(o->file.size + 1);
2564 memcpy(buf, o->file.ptr, o->file.size + 1);
2565 sb.final_buf = buf;
2566 sb.final_buf_size = o->file.size;
2567 }
2568 else {
2569 o = get_origin(&sb, sb.final, path);
2570 if (fill_blob_sha1_and_mode(o))
2571 die("no such path %s in %s", path, final_commit_name);
2572
2573 if (DIFF_OPT_TST(&sb.revs->diffopt, ALLOW_TEXTCONV) &&
2574 textconv_object(path, o->mode, o->blob_sha1, 1, (char **) &sb.final_buf,
2575 &sb.final_buf_size))
2576 ;
2577 else
2578 sb.final_buf = read_sha1_file(o->blob_sha1, &type,
2579 &sb.final_buf_size);
2580
2581 if (!sb.final_buf)
2582 die("Cannot read blob %s for path %s",
2583 sha1_to_hex(o->blob_sha1),
2584 path);
2585 }
2586 num_read_blob++;
2587 lno = prepare_lines(&sb);
2588
2589 bottom = top = 0;
2590 if (bottomtop)
2591 prepare_blame_range(&sb, bottomtop, lno, &bottom, &top);
2592 if (bottom && top && top < bottom) {
2593 long tmp;
2594 tmp = top; top = bottom; bottom = tmp;
2595 }
2596 if (bottom < 1)
2597 bottom = 1;
2598 if (top < 1)
2599 top = lno;
2600 bottom--;
2601 if (lno < top || lno < bottom)
2602 die("file %s has only %lu lines", path, lno);
2603
2604 ent = xcalloc(1, sizeof(*ent));
2605 ent->lno = bottom;
2606 ent->num_lines = top - bottom;
2607 ent->suspect = o;
2608 ent->s_lno = bottom;
2609
2610 sb.ent = ent;
2611 sb.path = path;
2612
2613 read_mailmap(&mailmap, NULL);
2614
2615 if (!incremental)
2616 setup_pager();
2617
2618 assign_blame(&sb, opt);
2619
2620 if (incremental)
2621 return 0;
2622
2623 coalesce(&sb);
2624
2625 if (!(output_option & OUTPUT_PORCELAIN))
2626 find_alignment(&sb, &output_option);
2627
2628 output(&sb, output_option);
2629 free((void *)sb.final_buf);
2630 for (ent = sb.ent; ent; ) {
2631 struct blame_entry *e = ent->next;
2632 free(ent);
2633 ent = e;
2634 }
2635
2636 if (show_stats) {
2637 printf("num read blob: %d\n", num_read_blob);
2638 printf("num get patch: %d\n", num_get_patch);
2639 printf("num commits: %d\n", num_commits);
2640 }
2641 return 0;
2642 }