Implement line-history search (git log -L)
[git/git.git] / line-log.c
1 #include "git-compat-util.h"
2 #include "line-range.h"
3 #include "cache.h"
4 #include "tag.h"
5 #include "blob.h"
6 #include "tree.h"
7 #include "diff.h"
8 #include "commit.h"
9 #include "decorate.h"
10 #include "revision.h"
11 #include "xdiff-interface.h"
12 #include "strbuf.h"
13 #include "log-tree.h"
14 #include "graph.h"
15 #include "line-log.h"
16
17 static void range_set_grow(struct range_set *rs, size_t extra)
18 {
19 ALLOC_GROW(rs->ranges, rs->nr + extra, rs->alloc);
20 }
21
22 /* Either initialization would be fine */
23 #define RANGE_SET_INIT {0}
24
25 static void range_set_init(struct range_set *rs, size_t prealloc)
26 {
27 rs->alloc = rs->nr = 0;
28 rs->ranges = NULL;
29 if (prealloc)
30 range_set_grow(rs, prealloc);
31 }
32
33 static void range_set_release(struct range_set *rs)
34 {
35 free(rs->ranges);
36 rs->alloc = rs->nr = 0;
37 rs->ranges = NULL;
38 }
39
40 /* dst must be uninitialized! */
41 static void range_set_copy(struct range_set *dst, struct range_set *src)
42 {
43 range_set_init(dst, src->nr);
44 memcpy(dst->ranges, src->ranges, src->nr*sizeof(struct range_set));
45 dst->nr = src->nr;
46 }
47 static void range_set_move(struct range_set *dst, struct range_set *src)
48 {
49 range_set_release(dst);
50 dst->ranges = src->ranges;
51 dst->nr = src->nr;
52 dst->alloc = src->alloc;
53 src->ranges = NULL;
54 src->alloc = src->nr = 0;
55 }
56
57 /* tack on a _new_ range _at the end_ */
58 static void range_set_append(struct range_set *rs, long a, long b)
59 {
60 assert(a <= b);
61 assert(rs->nr == 0 || rs->ranges[rs->nr-1].end <= a);
62 range_set_grow(rs, 1);
63 rs->ranges[rs->nr].start = a;
64 rs->ranges[rs->nr].end = b;
65 rs->nr++;
66 }
67
68 static int range_cmp(const void *_r, const void *_s)
69 {
70 const struct range *r = _r;
71 const struct range *s = _s;
72
73 /* this could be simply 'return r.start-s.start', but for the types */
74 if (r->start == s->start)
75 return 0;
76 if (r->start < s->start)
77 return -1;
78 return 1;
79 }
80
81 /*
82 * Helper: In-place pass of sorting and merging the ranges in the
83 * range set, to re-establish the invariants after another operation
84 *
85 * NEEDSWORK currently not needed
86 */
87 static void sort_and_merge_range_set(struct range_set *rs)
88 {
89 int i;
90 int o = 1; /* output cursor */
91
92 qsort(rs->ranges, rs->nr, sizeof(struct range), range_cmp);
93
94 for (i = 1; i < rs->nr; i++) {
95 if (rs->ranges[i].start <= rs->ranges[o-1].end) {
96 rs->ranges[o-1].end = rs->ranges[i].end;
97 } else {
98 rs->ranges[o].start = rs->ranges[i].start;
99 rs->ranges[o].end = rs->ranges[i].end;
100 o++;
101 }
102 }
103 assert(o <= rs->nr);
104 rs->nr = o;
105 }
106
107 /*
108 * Union of range sets (i.e., sets of line numbers). Used to merge
109 * them when searches meet at a common ancestor.
110 *
111 * This is also where the ranges are consolidated into canonical form:
112 * overlapping and adjacent ranges are merged, and empty ranges are
113 * removed.
114 */
115 static void range_set_union(struct range_set *out,
116 struct range_set *a, struct range_set *b)
117 {
118 int i = 0, j = 0, o = 0;
119 struct range *ra = a->ranges;
120 struct range *rb = b->ranges;
121 /* cannot make an alias of out->ranges: it may change during grow */
122
123 assert(out->nr == 0);
124 while (i < a->nr || j < b->nr) {
125 struct range *new;
126 if (i < a->nr && j < b->nr) {
127 if (ra[i].start < rb[j].start)
128 new = &ra[i++];
129 else if (ra[i].start > rb[j].start)
130 new = &rb[j++];
131 else if (ra[i].end < rb[j].end)
132 new = &ra[i++];
133 else
134 new = &rb[j++];
135 } else if (i < a->nr) /* b exhausted */
136 new = &ra[i++];
137 else /* a exhausted */
138 new = &rb[j++];
139 if (new->start == new->end)
140 ; /* empty range */
141 else if (!o || out->ranges[o-1].end < new->start) {
142 range_set_grow(out, 1);
143 out->ranges[o].start = new->start;
144 out->ranges[o].end = new->end;
145 o++;
146 } else if (out->ranges[o-1].end < new->end) {
147 out->ranges[o-1].end = new->end;
148 }
149 }
150 out->nr = o;
151 }
152
153 /*
154 * Difference of range sets (out = a \ b). Pass the "interesting"
155 * ranges as 'a' and the target side of the diff as 'b': it removes
156 * the ranges for which the commit is responsible.
157 */
158 static void range_set_difference(struct range_set *out,
159 struct range_set *a, struct range_set *b)
160 {
161 int i, j = 0;
162 for (i = 0; i < a->nr; i++) {
163 long start = a->ranges[i].start;
164 long end = a->ranges[i].end;
165 while (start < end) {
166 while (j < b->nr && start >= b->ranges[j].end)
167 /*
168 * a: |-------
169 * b: ------|
170 */
171 j++;
172 if (j >= b->nr || end < b->ranges[j].start) {
173 /*
174 * b exhausted, or
175 * a: ----|
176 * b: |----
177 */
178 range_set_append(out, start, end);
179 break;
180 }
181 if (start >= b->ranges[j].start) {
182 /*
183 * a: |--????
184 * b: |------|
185 */
186 start = b->ranges[j].end;
187 } else if (end > b->ranges[j].start) {
188 /*
189 * a: |-----|
190 * b: |--?????
191 */
192 if (start < b->ranges[j].start)
193 range_set_append(out, start, b->ranges[j].start);
194 start = b->ranges[j].end;
195 }
196 }
197 }
198 }
199
200 static void diff_ranges_init(struct diff_ranges *diff)
201 {
202 range_set_init(&diff->parent, 0);
203 range_set_init(&diff->target, 0);
204 }
205
206 static void diff_ranges_release(struct diff_ranges *diff)
207 {
208 range_set_release(&diff->parent);
209 range_set_release(&diff->target);
210 }
211
212 void line_log_data_init(struct line_log_data *r)
213 {
214 memset(r, 0, sizeof(struct line_log_data));
215 range_set_init(&r->ranges, 0);
216 }
217
218 static void line_log_data_clear(struct line_log_data *r)
219 {
220 range_set_release(&r->ranges);
221 if (r->pair)
222 diff_free_filepair(r->pair);
223 }
224
225 static void free_line_log_data(struct line_log_data *r)
226 {
227 while (r) {
228 struct line_log_data *next = r->next;
229 line_log_data_clear(r);
230 free(r);
231 r = next;
232 }
233 }
234
235 static struct line_log_data *
236 search_line_log_data(struct line_log_data *list, const char *path,
237 struct line_log_data **insertion_point)
238 {
239 struct line_log_data *p = list;
240 if (insertion_point)
241 *insertion_point = NULL;
242 while (p) {
243 int cmp = strcmp(p->spec->path, path);
244 if (!cmp)
245 return p;
246 if (insertion_point && cmp < 0)
247 *insertion_point = p;
248 p = p->next;
249 }
250 return NULL;
251 }
252
253 static void line_log_data_insert(struct line_log_data **list,
254 struct diff_filespec *spec,
255 long begin, long end)
256 {
257 struct line_log_data *ip;
258 struct line_log_data *p = search_line_log_data(*list, spec->path, &ip);
259
260 if (p) {
261 range_set_append(&p->ranges, begin, end);
262 sort_and_merge_range_set(&p->ranges);
263 free_filespec(spec);
264 return;
265 }
266
267 p = xcalloc(1, sizeof(struct line_log_data));
268 p->spec = spec;
269 range_set_append(&p->ranges, begin, end);
270 if (ip) {
271 p->next = ip->next;
272 ip->next = p;
273 } else {
274 p->next = *list;
275 *list = p;
276 }
277 }
278
279 struct collect_diff_cbdata {
280 struct diff_ranges *diff;
281 };
282
283 static int collect_diff_cb(long start_a, long count_a,
284 long start_b, long count_b,
285 void *data)
286 {
287 struct collect_diff_cbdata *d = data;
288
289 if (count_a >= 0)
290 range_set_append(&d->diff->parent, start_a, start_a + count_a);
291 if (count_b >= 0)
292 range_set_append(&d->diff->target, start_b, start_b + count_b);
293
294 return 0;
295 }
296
297 static void collect_diff(mmfile_t *parent, mmfile_t *target, struct diff_ranges *out)
298 {
299 struct collect_diff_cbdata cbdata = {NULL};
300 xpparam_t xpp;
301 xdemitconf_t xecfg;
302 xdemitcb_t ecb;
303
304 memset(&xpp, 0, sizeof(xpp));
305 memset(&xecfg, 0, sizeof(xecfg));
306 xecfg.ctxlen = xecfg.interhunkctxlen = 0;
307
308 cbdata.diff = out;
309 xecfg.hunk_func = collect_diff_cb;
310 memset(&ecb, 0, sizeof(ecb));
311 ecb.priv = &cbdata;
312 xdi_diff(parent, target, &xpp, &xecfg, &ecb);
313 }
314
315 /*
316 * These are handy for debugging. Removing them with #if 0 silences
317 * the "unused function" warning.
318 */
319 #if 0
320 static void dump_range_set(struct range_set *rs, const char *desc)
321 {
322 int i;
323 printf("range set %s (%d items):\n", desc, rs->nr);
324 for (i = 0; i < rs->nr; i++)
325 printf("\t[%ld,%ld]\n", rs->ranges[i].start, rs->ranges[i].end);
326 }
327
328 static void dump_line_log_data(struct line_log_data *r)
329 {
330 char buf[4096];
331 while (r) {
332 snprintf(buf, 4096, "file %s\n", r->spec->path);
333 dump_range_set(&r->ranges, buf);
334 r = r->next;
335 }
336 }
337
338 static void dump_diff_ranges(struct diff_ranges *diff, const char *desc)
339 {
340 int i;
341 assert(diff->parent.nr == diff->target.nr);
342 printf("diff ranges %s (%d items):\n", desc, diff->parent.nr);
343 printf("\tparent\ttarget\n");
344 for (i = 0; i < diff->parent.nr; i++) {
345 printf("\t[%ld,%ld]\t[%ld,%ld]\n",
346 diff->parent.ranges[i].start,
347 diff->parent.ranges[i].end,
348 diff->target.ranges[i].start,
349 diff->target.ranges[i].end);
350 }
351 }
352 #endif
353
354
355 static int ranges_overlap(struct range *a, struct range *b)
356 {
357 return !(a->end <= b->start || b->end <= a->start);
358 }
359
360 /*
361 * Given a diff and the set of interesting ranges, determine all hunks
362 * of the diff which touch (overlap) at least one of the interesting
363 * ranges in the target.
364 */
365 static void diff_ranges_filter_touched(struct diff_ranges *out,
366 struct diff_ranges *diff,
367 struct range_set *rs)
368 {
369 int i, j = 0;
370
371 assert(out->target.nr == 0);
372
373 for (i = 0; i < diff->target.nr; i++) {
374 while (diff->target.ranges[i].start > rs->ranges[j].end) {
375 j++;
376 if (j == rs->nr)
377 return;
378 }
379 if (ranges_overlap(&diff->target.ranges[i], &rs->ranges[j])) {
380 range_set_append(&out->parent,
381 diff->parent.ranges[i].start,
382 diff->parent.ranges[i].end);
383 range_set_append(&out->target,
384 diff->target.ranges[i].start,
385 diff->target.ranges[i].end);
386 }
387 }
388 }
389
390 /*
391 * Adjust the line counts in 'rs' to account for the lines
392 * added/removed in the diff.
393 */
394 static void range_set_shift_diff(struct range_set *out,
395 struct range_set *rs,
396 struct diff_ranges *diff)
397 {
398 int i, j = 0;
399 long offset = 0;
400 struct range *src = rs->ranges;
401 struct range *target = diff->target.ranges;
402 struct range *parent = diff->parent.ranges;
403
404 for (i = 0; i < rs->nr; i++) {
405 while (j < diff->target.nr && src[i].start >= target[j].start) {
406 offset += (parent[j].end-parent[j].start)
407 - (target[j].end-target[j].start);
408 j++;
409 }
410 range_set_append(out, src[i].start+offset, src[i].end+offset);
411 }
412 }
413
414 /*
415 * Given a diff and the set of interesting ranges, map the ranges
416 * across the diff. That is: observe that the target commit takes
417 * blame for all the + (target-side) ranges. So for every pair of
418 * ranges in the diff that was touched, we remove the latter and add
419 * its parent side.
420 */
421 static void range_set_map_across_diff(struct range_set *out,
422 struct range_set *rs,
423 struct diff_ranges *diff,
424 struct diff_ranges **touched_out)
425 {
426 struct diff_ranges *touched = xmalloc(sizeof(*touched));
427 struct range_set tmp1 = RANGE_SET_INIT;
428 struct range_set tmp2 = RANGE_SET_INIT;
429
430 diff_ranges_init(touched);
431 diff_ranges_filter_touched(touched, diff, rs);
432 range_set_difference(&tmp1, rs, &touched->target);
433 range_set_shift_diff(&tmp2, &tmp1, diff);
434 range_set_union(out, &tmp2, &touched->parent);
435 range_set_release(&tmp1);
436 range_set_release(&tmp2);
437
438 *touched_out = touched;
439 }
440
441
442 static struct commit *check_single_commit(struct rev_info *revs)
443 {
444 struct object *commit = NULL;
445 int found = -1;
446 int i;
447
448 for (i = 0; i < revs->pending.nr; i++) {
449 struct object *obj = revs->pending.objects[i].item;
450 if (obj->flags & UNINTERESTING)
451 continue;
452 while (obj->type == OBJ_TAG)
453 obj = deref_tag(obj, NULL, 0);
454 if (obj->type != OBJ_COMMIT)
455 die("Non commit %s?", revs->pending.objects[i].name);
456 if (commit)
457 die("More than one commit to dig from: %s and %s?",
458 revs->pending.objects[i].name,
459 revs->pending.objects[found].name);
460 commit = obj;
461 found = i;
462 }
463
464 if (!commit)
465 die("No commit specified?");
466
467 return (struct commit *) commit;
468 }
469
470 static void fill_blob_sha1(struct commit *commit, struct diff_filespec *spec)
471 {
472 unsigned mode;
473 unsigned char sha1[20];
474
475 if (get_tree_entry(commit->object.sha1, spec->path,
476 sha1, &mode))
477 die("There is no path %s in the commit", spec->path);
478 fill_filespec(spec, sha1, 1, mode);
479
480 return;
481 }
482
483 static void fill_line_ends(struct diff_filespec *spec, long *lines,
484 unsigned long **line_ends)
485 {
486 int num = 0, size = 50;
487 long cur = 0;
488 unsigned long *ends = NULL;
489 char *data = NULL;
490
491 if (diff_populate_filespec(spec, 0))
492 die("Cannot read blob %s", sha1_to_hex(spec->sha1));
493
494 ends = xmalloc(size * sizeof(*ends));
495 ends[cur++] = 0;
496 data = spec->data;
497 while (num < spec->size) {
498 if (data[num] == '\n' || num == spec->size - 1) {
499 ALLOC_GROW(ends, (cur + 1), size);
500 ends[cur++] = num;
501 }
502 num++;
503 }
504
505 /* shrink the array to fit the elements */
506 ends = xrealloc(ends, cur * sizeof(*ends));
507 *lines = cur-1;
508 *line_ends = ends;
509 }
510
511 struct nth_line_cb {
512 struct diff_filespec *spec;
513 long lines;
514 unsigned long *line_ends;
515 };
516
517 static const char *nth_line(void *data, long line)
518 {
519 struct nth_line_cb *d = data;
520 assert(d && line <= d->lines);
521 assert(d->spec && d->spec->data);
522
523 if (line == 0)
524 return (char *)d->spec->data;
525 else
526 return (char *)d->spec->data + d->line_ends[line] + 1;
527 }
528
529 static struct line_log_data *
530 parse_lines(struct commit *commit, const char *prefix, struct string_list *args)
531 {
532 long lines = 0;
533 unsigned long *ends = NULL;
534 struct nth_line_cb cb_data;
535 struct string_list_item *item;
536 struct line_log_data *ranges = NULL;
537
538 for_each_string_list_item(item, args) {
539 const char *name_part, *range_part;
540 const char *full_name;
541 struct diff_filespec *spec;
542 long begin = 0, end = 0;
543
544 name_part = skip_range_arg(item->string);
545 if (!name_part || *name_part != ':' || !name_part[1])
546 die("-L argument '%s' not of the form start,end:file",
547 item->string);
548 range_part = xstrndup(item->string, name_part - item->string);
549 name_part++;
550
551 full_name = prefix_path(prefix, prefix ? strlen(prefix) : 0,
552 name_part);
553
554 spec = alloc_filespec(full_name);
555 fill_blob_sha1(commit, spec);
556 fill_line_ends(spec, &lines, &ends);
557 cb_data.spec = spec;
558 cb_data.lines = lines;
559 cb_data.line_ends = ends;
560
561 if (parse_range_arg(range_part, nth_line, &cb_data,
562 lines, &begin, &end))
563 die("malformed -L argument '%s'", range_part);
564 if (begin < 1)
565 begin = 1;
566 if (end < 1)
567 end = lines;
568 begin--;
569 if (lines < end || lines < begin)
570 die("file %s has only %ld lines", name_part, lines);
571 line_log_data_insert(&ranges, spec, begin, end);
572
573 free(ends);
574 ends = NULL;
575 }
576
577 return ranges;
578 }
579
580 static struct line_log_data *line_log_data_copy_one(struct line_log_data *r)
581 {
582 struct line_log_data *ret = xmalloc(sizeof(*ret));
583
584 assert(r);
585 line_log_data_init(ret);
586 range_set_copy(&ret->ranges, &r->ranges);
587
588 ret->spec = r->spec;
589 assert(ret->spec);
590 ret->spec->count++;
591
592 return ret;
593 }
594
595 static struct line_log_data *
596 line_log_data_copy(struct line_log_data *r)
597 {
598 struct line_log_data *ret = NULL;
599 struct line_log_data *tmp = NULL, *prev = NULL;
600
601 assert(r);
602 ret = tmp = prev = line_log_data_copy_one(r);
603 r = r->next;
604 while (r) {
605 tmp = line_log_data_copy_one(r);
606 prev->next = tmp;
607 prev = tmp;
608 r = r->next;
609 }
610
611 return ret;
612 }
613
614 /* merge two range sets across files */
615 static struct line_log_data *line_log_data_merge(struct line_log_data *a,
616 struct line_log_data *b)
617 {
618 struct line_log_data *head = NULL, **pp = &head;
619
620 while (a || b) {
621 struct line_log_data *src;
622 struct line_log_data *src2 = NULL;
623 struct line_log_data *d;
624 int cmp;
625 if (!a)
626 cmp = 1;
627 else if (!b)
628 cmp = -1;
629 else
630 cmp = strcmp(a->spec->path, b->spec->path);
631 if (cmp < 0) {
632 src = a;
633 a = a->next;
634 } else if (cmp == 0) {
635 src = a;
636 a = a->next;
637 src2 = b;
638 b = b->next;
639 } else {
640 src = b;
641 b = b->next;
642 }
643 d = xmalloc(sizeof(struct line_log_data));
644 line_log_data_init(d);
645 d->spec = src->spec;
646 d->spec->count++;
647 *pp = d;
648 pp = &d->next;
649 if (src2)
650 range_set_union(&d->ranges, &src->ranges, &src2->ranges);
651 else
652 range_set_copy(&d->ranges, &src->ranges);
653 }
654
655 return head;
656 }
657
658 static void add_line_range(struct rev_info *revs, struct commit *commit,
659 struct line_log_data *range)
660 {
661 struct line_log_data *old = NULL;
662 struct line_log_data *new = NULL;
663
664 old = lookup_decoration(&revs->line_log_data, &commit->object);
665 if (old && range) {
666 new = line_log_data_merge(old, range);
667 free_line_log_data(old);
668 } else if (range)
669 new = line_log_data_copy(range);
670
671 if (new)
672 add_decoration(&revs->line_log_data, &commit->object, new);
673 }
674
675 static void clear_commit_line_range(struct rev_info *revs, struct commit *commit)
676 {
677 struct line_log_data *r;
678 r = lookup_decoration(&revs->line_log_data, &commit->object);
679 if (!r)
680 return;
681 free_line_log_data(r);
682 add_decoration(&revs->line_log_data, &commit->object, NULL);
683 }
684
685 static struct line_log_data *lookup_line_range(struct rev_info *revs,
686 struct commit *commit)
687 {
688 struct line_log_data *ret = NULL;
689
690 ret = lookup_decoration(&revs->line_log_data, &commit->object);
691 return ret;
692 }
693
694 void line_log_init(struct rev_info *rev, const char *prefix, struct string_list *args)
695 {
696 struct commit *commit = NULL;
697 struct line_log_data *range;
698
699 commit = check_single_commit(rev);
700 range = parse_lines(commit, prefix, args);
701 add_line_range(rev, commit, range);
702
703 if (!rev->diffopt.detect_rename) {
704 int i, count = 0;
705 struct line_log_data *r = range;
706 const char **paths;
707 while (r) {
708 count++;
709 r = r->next;
710 }
711 paths = xmalloc((count+1)*sizeof(char *));
712 r = range;
713 for (i = 0; i < count; i++) {
714 paths[i] = xstrdup(r->spec->path);
715 r = r->next;
716 }
717 paths[count] = NULL;
718 init_pathspec(&rev->diffopt.pathspec, paths);
719 free(paths);
720 }
721 }
722
723 static void load_tree_desc(struct tree_desc *desc, void **tree,
724 const unsigned char *sha1)
725 {
726 unsigned long size;
727 *tree = read_object_with_reference(sha1, tree_type, &size, NULL);
728 if (!*tree)
729 die("Unable to read tree (%s)", sha1_to_hex(sha1));
730 init_tree_desc(desc, *tree, size);
731 }
732
733 static int count_parents(struct commit *commit)
734 {
735 struct commit_list *parents = commit->parents;
736 int count = 0;
737 while (parents) {
738 count++;
739 parents = parents->next;
740 }
741 return count;
742 }
743
744 static void move_diff_queue(struct diff_queue_struct *dst,
745 struct diff_queue_struct *src)
746 {
747 assert(src != dst);
748 memcpy(dst, src, sizeof(struct diff_queue_struct));
749 DIFF_QUEUE_CLEAR(src);
750 }
751
752 static void queue_diffs(struct diff_options *opt,
753 struct diff_queue_struct *queue,
754 struct commit *commit, struct commit *parent)
755 {
756 void *tree1 = NULL, *tree2 = NULL;
757 struct tree_desc desc1, desc2;
758
759 assert(commit);
760 load_tree_desc(&desc2, &tree2, commit->tree->object.sha1);
761 if (parent)
762 load_tree_desc(&desc1, &tree1, parent->tree->object.sha1);
763 else
764 init_tree_desc(&desc1, "", 0);
765
766 DIFF_QUEUE_CLEAR(&diff_queued_diff);
767 diff_tree(&desc1, &desc2, "", opt);
768 diffcore_std(opt);
769 move_diff_queue(queue, &diff_queued_diff);
770
771 if (tree1)
772 free(tree1);
773 if (tree2)
774 free(tree2);
775 }
776
777 static char *get_nth_line(long line, unsigned long *ends, void *data)
778 {
779 if (line == 0)
780 return (char *)data;
781 else
782 return (char *)data + ends[line] + 1;
783 }
784
785 static void print_line(const char *prefix, char first,
786 long line, unsigned long *ends, void *data,
787 const char *color, const char *reset)
788 {
789 char *begin = get_nth_line(line, ends, data);
790 char *end = get_nth_line(line+1, ends, data);
791 int had_nl = 0;
792
793 if (end > begin && end[-1] == '\n') {
794 end--;
795 had_nl = 1;
796 }
797
798 fputs(prefix, stdout);
799 fputs(color, stdout);
800 putchar(first);
801 fwrite(begin, 1, end-begin, stdout);
802 fputs(reset, stdout);
803 putchar('\n');
804 if (!had_nl)
805 fputs("\\ No newline at end of file\n", stdout);
806 }
807
808 static char *output_prefix(struct diff_options *opt)
809 {
810 char *prefix = "";
811
812 if (opt->output_prefix) {
813 struct strbuf *sb = opt->output_prefix(opt, opt->output_prefix_data);
814 prefix = sb->buf;
815 }
816
817 return prefix;
818 }
819
820 static void dump_diff_hacky_one(struct rev_info *rev, struct line_log_data *range)
821 {
822 int i, j = 0;
823 long p_lines, t_lines;
824 unsigned long *p_ends = NULL, *t_ends = NULL;
825 struct diff_filepair *pair = range->pair;
826 struct diff_ranges *diff = &range->diff;
827
828 struct diff_options *opt = &rev->diffopt;
829 char *prefix = output_prefix(opt);
830 const char *c_reset = diff_get_color(opt->use_color, DIFF_RESET);
831 const char *c_frag = diff_get_color(opt->use_color, DIFF_FRAGINFO);
832 const char *c_meta = diff_get_color(opt->use_color, DIFF_METAINFO);
833 const char *c_old = diff_get_color(opt->use_color, DIFF_FILE_OLD);
834 const char *c_new = diff_get_color(opt->use_color, DIFF_FILE_NEW);
835 const char *c_plain = diff_get_color(opt->use_color, DIFF_PLAIN);
836
837 if (!pair || !diff)
838 return;
839
840 if (pair->one->sha1_valid)
841 fill_line_ends(pair->one, &p_lines, &p_ends);
842 fill_line_ends(pair->two, &t_lines, &t_ends);
843
844 printf("%s%sdiff --git a/%s b/%s%s\n", prefix, c_meta, pair->one->path, pair->two->path, c_reset);
845 printf("%s%s--- %s%s%s\n", prefix, c_meta,
846 pair->one->sha1_valid ? "a/" : "",
847 pair->one->sha1_valid ? pair->one->path : "/dev/null",
848 c_reset);
849 printf("%s%s+++ b/%s%s\n", prefix, c_meta, pair->two->path, c_reset);
850 for (i = 0; i < range->ranges.nr; i++) {
851 long p_start, p_end;
852 long t_start = range->ranges.ranges[i].start;
853 long t_end = range->ranges.ranges[i].end;
854 long t_cur = t_start;
855 int j_last;
856
857 while (j < diff->target.nr && diff->target.ranges[j].end < t_start)
858 j++;
859 if (j == diff->target.nr || diff->target.ranges[j].start > t_end)
860 continue;
861
862 /* Scan ahead to determine the last diff that falls in this range */
863 j_last = j;
864 while (j_last < diff->target.nr && diff->target.ranges[j_last].start < t_end)
865 j_last++;
866 if (j_last > j)
867 j_last--;
868
869 /*
870 * Compute parent hunk headers: we know that the diff
871 * has the correct line numbers (but not all hunks).
872 * So it suffices to shift the start/end according to
873 * the line numbers of the first/last hunk(s) that
874 * fall in this range.
875 */
876 if (t_start < diff->target.ranges[j].start)
877 p_start = diff->parent.ranges[j].start - (diff->target.ranges[j].start-t_start);
878 else
879 p_start = diff->parent.ranges[j].start;
880 if (t_end > diff->target.ranges[j_last].end)
881 p_end = diff->parent.ranges[j_last].end + (t_end-diff->target.ranges[j_last].end);
882 else
883 p_end = diff->parent.ranges[j_last].end;
884
885 if (!p_start && !p_end) {
886 p_start = -1;
887 p_end = -1;
888 }
889
890 /* Now output a diff hunk for this range */
891 printf("%s%s@@ -%ld,%ld +%ld,%ld @@%s\n",
892 prefix, c_frag,
893 p_start+1, p_end-p_start, t_start+1, t_end-t_start,
894 c_reset);
895 while (j < diff->target.nr && diff->target.ranges[j].start < t_end) {
896 int k;
897 for (; t_cur < diff->target.ranges[j].start; t_cur++)
898 print_line(prefix, ' ', t_cur, t_ends, pair->two->data,
899 c_plain, c_reset);
900 for (k = diff->parent.ranges[j].start; k < diff->parent.ranges[j].end; k++)
901 print_line(prefix, '-', k, p_ends, pair->one->data,
902 c_old, c_reset);
903 for (; t_cur < diff->target.ranges[j].end && t_cur < t_end; t_cur++)
904 print_line(prefix, '+', t_cur, t_ends, pair->two->data,
905 c_new, c_reset);
906 j++;
907 }
908 for (; t_cur < t_end; t_cur++)
909 print_line(prefix, ' ', t_cur, t_ends, pair->two->data,
910 c_plain, c_reset);
911 }
912
913 free(p_ends);
914 free(t_ends);
915 }
916
917 /*
918 * NEEDSWORK: manually building a diff here is not the Right
919 * Thing(tm). log -L should be built into the diff pipeline.
920 */
921 static void dump_diff_hacky(struct rev_info *rev, struct line_log_data *range)
922 {
923 puts(output_prefix(&rev->diffopt));
924 while (range) {
925 dump_diff_hacky_one(rev, range);
926 range = range->next;
927 }
928 }
929
930 /*
931 * Unlike most other functions, this destructively operates on
932 * 'range'.
933 */
934 static int process_diff_filepair(struct rev_info *rev,
935 struct diff_filepair *pair,
936 struct line_log_data *range,
937 struct diff_ranges **diff_out)
938 {
939 struct line_log_data *rg = range;
940 struct range_set tmp;
941 struct diff_ranges diff;
942 mmfile_t file_parent, file_target;
943
944 assert(pair->two->path);
945 while (rg) {
946 assert(rg->spec->path);
947 if (!strcmp(rg->spec->path, pair->two->path))
948 break;
949 rg = rg->next;
950 }
951
952 if (!rg)
953 return 0;
954 if (rg->ranges.nr == 0)
955 return 0;
956
957 assert(pair->two->sha1_valid);
958 diff_populate_filespec(pair->two, 0);
959 file_target.ptr = pair->two->data;
960 file_target.size = pair->two->size;
961
962 if (pair->one->sha1_valid) {
963 diff_populate_filespec(pair->one, 0);
964 file_parent.ptr = pair->one->data;
965 file_parent.size = pair->one->size;
966 } else {
967 file_parent.ptr = "";
968 file_parent.size = 0;
969 }
970
971 diff_ranges_init(&diff);
972 collect_diff(&file_parent, &file_target, &diff);
973
974 /* NEEDSWORK should apply some heuristics to prevent mismatches */
975 rg->spec->path = xstrdup(pair->one->path);
976
977 range_set_init(&tmp, 0);
978 range_set_map_across_diff(&tmp, &rg->ranges, &diff, diff_out);
979 range_set_release(&rg->ranges);
980 range_set_move(&rg->ranges, &tmp);
981
982 diff_ranges_release(&diff);
983
984 return ((*diff_out)->parent.nr > 0);
985 }
986
987 static struct diff_filepair *diff_filepair_dup(struct diff_filepair *pair)
988 {
989 struct diff_filepair *new = xmalloc(sizeof(struct diff_filepair));
990 new->one = pair->one;
991 new->two = pair->two;
992 new->one->count++;
993 new->two->count++;
994 return new;
995 }
996
997 static void free_diffqueues(int n, struct diff_queue_struct *dq)
998 {
999 int i, j;
1000 for (i = 0; i < n; i++)
1001 for (j = 0; j < dq[i].nr; j++)
1002 diff_free_filepair(dq[i].queue[j]);
1003 free(dq);
1004 }
1005
1006 static int process_all_files(struct line_log_data **range_out,
1007 struct rev_info *rev,
1008 struct diff_queue_struct *queue,
1009 struct line_log_data *range)
1010 {
1011 int i, changed = 0;
1012
1013 *range_out = line_log_data_copy(range);
1014
1015 for (i = 0; i < queue->nr; i++) {
1016 struct diff_ranges *pairdiff = NULL;
1017 if (process_diff_filepair(rev, queue->queue[i], *range_out, &pairdiff)) {
1018 struct line_log_data *rg = range;
1019 changed++;
1020 /* NEEDSWORK tramples over data structures not owned here */
1021 while (rg && strcmp(rg->spec->path, queue->queue[i]->two->path))
1022 rg = rg->next;
1023 assert(rg);
1024 rg->pair = diff_filepair_dup(queue->queue[i]);
1025 memcpy(&rg->diff, pairdiff, sizeof(struct diff_ranges));
1026 }
1027 }
1028
1029 return changed;
1030 }
1031
1032 int line_log_print(struct rev_info *rev, struct commit *commit)
1033 {
1034 struct line_log_data *range = lookup_line_range(rev, commit);
1035
1036 show_log(rev);
1037 dump_diff_hacky(rev, range);
1038 return 1;
1039 }
1040
1041 static int process_ranges_ordinary_commit(struct rev_info *rev, struct commit *commit,
1042 struct line_log_data *range)
1043 {
1044 struct commit *parent = NULL;
1045 struct diff_queue_struct queue;
1046 struct line_log_data *parent_range;
1047 int changed;
1048
1049 if (commit->parents)
1050 parent = commit->parents->item;
1051
1052 queue_diffs(&rev->diffopt, &queue, commit, parent);
1053 changed = process_all_files(&parent_range, rev, &queue, range);
1054 if (parent)
1055 add_line_range(rev, parent, parent_range);
1056 return changed;
1057 }
1058
1059 static int process_ranges_merge_commit(struct rev_info *rev, struct commit *commit,
1060 struct line_log_data *range)
1061 {
1062 struct diff_queue_struct *diffqueues;
1063 struct line_log_data **cand;
1064 struct commit **parents;
1065 struct commit_list *p;
1066 int i;
1067 int nparents = count_parents(commit);
1068
1069 diffqueues = xmalloc(nparents * sizeof(*diffqueues));
1070 cand = xmalloc(nparents * sizeof(*cand));
1071 parents = xmalloc(nparents * sizeof(*parents));
1072
1073 p = commit->parents;
1074 for (i = 0; i < nparents; i++) {
1075 parents[i] = p->item;
1076 p = p->next;
1077 queue_diffs(&rev->diffopt, &diffqueues[i], commit, parents[i]);
1078 }
1079
1080 for (i = 0; i < nparents; i++) {
1081 int changed;
1082 cand[i] = NULL;
1083 changed = process_all_files(&cand[i], rev, &diffqueues[i], range);
1084 if (!changed) {
1085 /*
1086 * This parent can take all the blame, so we
1087 * don't follow any other path in history
1088 */
1089 add_line_range(rev, parents[i], cand[i]);
1090 clear_commit_line_range(rev, commit);
1091 commit->parents = xmalloc(sizeof(struct commit_list));
1092 commit->parents->item = parents[i];
1093 commit->parents->next = NULL;
1094 free(parents);
1095 free(cand);
1096 free_diffqueues(nparents, diffqueues);
1097 /* NEEDSWORK leaking like a sieve */
1098 return 0;
1099 }
1100 }
1101
1102 /*
1103 * No single parent took the blame. We add the candidates
1104 * from the above loop to the parents.
1105 */
1106 for (i = 0; i < nparents; i++) {
1107 add_line_range(rev, parents[i], cand[i]);
1108 }
1109
1110 clear_commit_line_range(rev, commit);
1111 free(parents);
1112 free(cand);
1113 free_diffqueues(nparents, diffqueues);
1114 return 1;
1115
1116 /* NEEDSWORK evil merge detection stuff */
1117 /* NEEDSWORK leaking like a sieve */
1118 }
1119
1120 static int process_ranges_arbitrary_commit(struct rev_info *rev, struct commit *commit)
1121 {
1122 struct line_log_data *range = lookup_line_range(rev, commit);
1123 int changed = 0;
1124
1125 if (range) {
1126 if (!commit->parents || !commit->parents->next)
1127 changed = process_ranges_ordinary_commit(rev, commit, range);
1128 else
1129 changed = process_ranges_merge_commit(rev, commit, range);
1130 }
1131
1132 if (!changed)
1133 commit->object.flags |= TREESAME;
1134
1135 return changed;
1136 }
1137
1138 static enum rewrite_result line_log_rewrite_one(struct rev_info *rev, struct commit **pp)
1139 {
1140 for (;;) {
1141 struct commit *p = *pp;
1142 if (p->parents && p->parents->next)
1143 return rewrite_one_ok;
1144 if (p->object.flags & UNINTERESTING)
1145 return rewrite_one_ok;
1146 if (!(p->object.flags & TREESAME))
1147 return rewrite_one_ok;
1148 if (!p->parents)
1149 return rewrite_one_noparents;
1150 *pp = p->parents->item;
1151 }
1152 }
1153
1154 int line_log_filter(struct rev_info *rev)
1155 {
1156 struct commit *commit;
1157 struct commit_list *list = rev->commits;
1158 struct commit_list *out = NULL, **pp = &out;
1159
1160 while (list) {
1161 struct commit_list *to_free = NULL;
1162 commit = list->item;
1163 if (process_ranges_arbitrary_commit(rev, commit)) {
1164 *pp = list;
1165 pp = &list->next;
1166 } else
1167 to_free = list;
1168 list = list->next;
1169 free(to_free);
1170 }
1171 *pp = NULL;
1172
1173 for (list = out; list; list = list->next)
1174 rewrite_parents(rev, list->item, line_log_rewrite_one);
1175
1176 rev->commits = out;
1177
1178 return 0;
1179 }