Merge branch 'rs/plug-leak-in-pack-bitmaps' into maint
[git.git] / combine-diff.c
blob91edce58e15b82428fcc5f3b006e23bf5380d38c
1 #include "cache.h"
2 #include "commit.h"
3 #include "blob.h"
4 #include "diff.h"
5 #include "diffcore.h"
6 #include "quote.h"
7 #include "xdiff-interface.h"
8 #include "xdiff/xmacros.h"
9 #include "log-tree.h"
10 #include "refs.h"
11 #include "userdiff.h"
12 #include "sha1-array.h"
13 #include "revision.h"
15 static int compare_paths(const struct combine_diff_path *one,
16 const struct diff_filespec *two)
18 if (!S_ISDIR(one->mode) && !S_ISDIR(two->mode))
19 return strcmp(one->path, two->path);
21 return base_name_compare(one->path, strlen(one->path), one->mode,
22 two->path, strlen(two->path), two->mode);
25 static struct combine_diff_path *intersect_paths(struct combine_diff_path *curr, int n, int num_parent)
27 struct diff_queue_struct *q = &diff_queued_diff;
28 struct combine_diff_path *p, **tail = &curr;
29 int i, cmp;
31 if (!n) {
32 for (i = 0; i < q->nr; i++) {
33 int len;
34 const char *path;
35 if (diff_unmodified_pair(q->queue[i]))
36 continue;
37 path = q->queue[i]->two->path;
38 len = strlen(path);
39 p = xmalloc(combine_diff_path_size(num_parent, len));
40 p->path = (char *) &(p->parent[num_parent]);
41 memcpy(p->path, path, len);
42 p->path[len] = 0;
43 p->next = NULL;
44 memset(p->parent, 0,
45 sizeof(p->parent[0]) * num_parent);
47 hashcpy(p->sha1, q->queue[i]->two->sha1);
48 p->mode = q->queue[i]->two->mode;
49 hashcpy(p->parent[n].sha1, q->queue[i]->one->sha1);
50 p->parent[n].mode = q->queue[i]->one->mode;
51 p->parent[n].status = q->queue[i]->status;
52 *tail = p;
53 tail = &p->next;
55 return curr;
59 * paths in curr (linked list) and q->queue[] (array) are
60 * both sorted in the tree order.
62 i = 0;
63 while ((p = *tail) != NULL) {
64 cmp = ((i >= q->nr)
65 ? -1 : compare_paths(p, q->queue[i]->two));
67 if (cmp < 0) {
68 /* p->path not in q->queue[]; drop it */
69 *tail = p->next;
70 free(p);
71 continue;
74 if (cmp > 0) {
75 /* q->queue[i] not in p->path; skip it */
76 i++;
77 continue;
80 hashcpy(p->parent[n].sha1, q->queue[i]->one->sha1);
81 p->parent[n].mode = q->queue[i]->one->mode;
82 p->parent[n].status = q->queue[i]->status;
84 tail = &p->next;
85 i++;
87 return curr;
90 /* Lines lost from parent */
91 struct lline {
92 struct lline *next, *prev;
93 int len;
94 unsigned long parent_map;
95 char line[FLEX_ARRAY];
98 /* Lines lost from current parent (before coalescing) */
99 struct plost {
100 struct lline *lost_head, *lost_tail;
101 int len;
104 /* Lines surviving in the merge result */
105 struct sline {
106 /* Accumulated and coalesced lost lines */
107 struct lline *lost;
108 int lenlost;
109 struct plost plost;
110 char *bol;
111 int len;
112 /* bit 0 up to (N-1) are on if the parent has this line (i.e.
113 * we did not change it).
114 * bit N is used for "interesting" lines, including context.
115 * bit (N+1) is used for "do not show deletion before this".
117 unsigned long flag;
118 unsigned long *p_lno;
121 static int match_string_spaces(const char *line1, int len1,
122 const char *line2, int len2,
123 long flags)
125 if (flags & XDF_WHITESPACE_FLAGS) {
126 for (; len1 > 0 && XDL_ISSPACE(line1[len1 - 1]); len1--);
127 for (; len2 > 0 && XDL_ISSPACE(line2[len2 - 1]); len2--);
130 if (!(flags & (XDF_IGNORE_WHITESPACE | XDF_IGNORE_WHITESPACE_CHANGE)))
131 return (len1 == len2 && !memcmp(line1, line2, len1));
133 while (len1 > 0 && len2 > 0) {
134 len1--;
135 len2--;
136 if (XDL_ISSPACE(line1[len1]) || XDL_ISSPACE(line2[len2])) {
137 if ((flags & XDF_IGNORE_WHITESPACE_CHANGE) &&
138 (!XDL_ISSPACE(line1[len1]) || !XDL_ISSPACE(line2[len2])))
139 return 0;
141 for (; len1 > 0 && XDL_ISSPACE(line1[len1]); len1--);
142 for (; len2 > 0 && XDL_ISSPACE(line2[len2]); len2--);
144 if (line1[len1] != line2[len2])
145 return 0;
148 if (flags & XDF_IGNORE_WHITESPACE) {
149 /* Consume remaining spaces */
150 for (; len1 > 0 && XDL_ISSPACE(line1[len1 - 1]); len1--);
151 for (; len2 > 0 && XDL_ISSPACE(line2[len2 - 1]); len2--);
154 /* We matched full line1 and line2 */
155 if (!len1 && !len2)
156 return 1;
158 return 0;
161 enum coalesce_direction { MATCH, BASE, NEW };
163 /* Coalesce new lines into base by finding LCS */
164 static struct lline *coalesce_lines(struct lline *base, int *lenbase,
165 struct lline *new, int lennew,
166 unsigned long parent, long flags)
168 int **lcs;
169 enum coalesce_direction **directions;
170 struct lline *baseend, *newend = NULL;
171 int i, j, origbaselen = *lenbase;
173 if (new == NULL)
174 return base;
176 if (base == NULL) {
177 *lenbase = lennew;
178 return new;
182 * Coalesce new lines into base by finding the LCS
183 * - Create the table to run dynamic programming
184 * - Compute the LCS
185 * - Then reverse read the direction structure:
186 * - If we have MATCH, assign parent to base flag, and consume
187 * both baseend and newend
188 * - Else if we have BASE, consume baseend
189 * - Else if we have NEW, insert newend lline into base and
190 * consume newend
192 lcs = xcalloc(origbaselen + 1, sizeof(int*));
193 directions = xcalloc(origbaselen + 1, sizeof(enum coalesce_direction*));
194 for (i = 0; i < origbaselen + 1; i++) {
195 lcs[i] = xcalloc(lennew + 1, sizeof(int));
196 directions[i] = xcalloc(lennew + 1, sizeof(enum coalesce_direction));
197 directions[i][0] = BASE;
199 for (j = 1; j < lennew + 1; j++)
200 directions[0][j] = NEW;
202 for (i = 1, baseend = base; i < origbaselen + 1; i++) {
203 for (j = 1, newend = new; j < lennew + 1; j++) {
204 if (match_string_spaces(baseend->line, baseend->len,
205 newend->line, newend->len, flags)) {
206 lcs[i][j] = lcs[i - 1][j - 1] + 1;
207 directions[i][j] = MATCH;
208 } else if (lcs[i][j - 1] >= lcs[i - 1][j]) {
209 lcs[i][j] = lcs[i][j - 1];
210 directions[i][j] = NEW;
211 } else {
212 lcs[i][j] = lcs[i - 1][j];
213 directions[i][j] = BASE;
215 if (newend->next)
216 newend = newend->next;
218 if (baseend->next)
219 baseend = baseend->next;
222 for (i = 0; i < origbaselen + 1; i++)
223 free(lcs[i]);
224 free(lcs);
226 /* At this point, baseend and newend point to the end of each lists */
227 i--;
228 j--;
229 while (i != 0 || j != 0) {
230 if (directions[i][j] == MATCH) {
231 baseend->parent_map |= 1<<parent;
232 baseend = baseend->prev;
233 newend = newend->prev;
234 i--;
235 j--;
236 } else if (directions[i][j] == NEW) {
237 struct lline *lline;
239 lline = newend;
240 /* Remove lline from new list and update newend */
241 if (lline->prev)
242 lline->prev->next = lline->next;
243 else
244 new = lline->next;
245 if (lline->next)
246 lline->next->prev = lline->prev;
248 newend = lline->prev;
249 j--;
251 /* Add lline to base list */
252 if (baseend) {
253 lline->next = baseend->next;
254 lline->prev = baseend;
255 if (lline->prev)
256 lline->prev->next = lline;
258 else {
259 lline->next = base;
260 base = lline;
262 (*lenbase)++;
264 if (lline->next)
265 lline->next->prev = lline;
267 } else {
268 baseend = baseend->prev;
269 i--;
273 newend = new;
274 while (newend) {
275 struct lline *lline = newend;
276 newend = newend->next;
277 free(lline);
280 for (i = 0; i < origbaselen + 1; i++)
281 free(directions[i]);
282 free(directions);
284 return base;
287 static char *grab_blob(const unsigned char *sha1, unsigned int mode,
288 unsigned long *size, struct userdiff_driver *textconv,
289 const char *path)
291 char *blob;
292 enum object_type type;
294 if (S_ISGITLINK(mode)) {
295 blob = xmalloc(100);
296 *size = snprintf(blob, 100,
297 "Subproject commit %s\n", sha1_to_hex(sha1));
298 } else if (is_null_sha1(sha1)) {
299 /* deleted blob */
300 *size = 0;
301 return xcalloc(1, 1);
302 } else if (textconv) {
303 struct diff_filespec *df = alloc_filespec(path);
304 fill_filespec(df, sha1, 1, mode);
305 *size = fill_textconv(textconv, df, &blob);
306 free_filespec(df);
307 } else {
308 blob = read_sha1_file(sha1, &type, size);
309 if (type != OBJ_BLOB)
310 die("object '%s' is not a blob!", sha1_to_hex(sha1));
312 return blob;
315 static void append_lost(struct sline *sline, int n, const char *line, int len)
317 struct lline *lline;
318 unsigned long this_mask = (1UL<<n);
319 if (line[len-1] == '\n')
320 len--;
322 lline = xmalloc(sizeof(*lline) + len + 1);
323 lline->len = len;
324 lline->next = NULL;
325 lline->prev = sline->plost.lost_tail;
326 if (lline->prev)
327 lline->prev->next = lline;
328 else
329 sline->plost.lost_head = lline;
330 sline->plost.lost_tail = lline;
331 sline->plost.len++;
332 lline->parent_map = this_mask;
333 memcpy(lline->line, line, len);
334 lline->line[len] = 0;
337 struct combine_diff_state {
338 unsigned int lno;
339 int ob, on, nb, nn;
340 unsigned long nmask;
341 int num_parent;
342 int n;
343 struct sline *sline;
344 struct sline *lost_bucket;
347 static void consume_line(void *state_, char *line, unsigned long len)
349 struct combine_diff_state *state = state_;
350 if (5 < len && !memcmp("@@ -", line, 4)) {
351 if (parse_hunk_header(line, len,
352 &state->ob, &state->on,
353 &state->nb, &state->nn))
354 return;
355 state->lno = state->nb;
356 if (state->nn == 0) {
357 /* @@ -X,Y +N,0 @@ removed Y lines
358 * that would have come *after* line N
359 * in the result. Our lost buckets hang
360 * to the line after the removed lines,
362 * Note that this is correct even when N == 0,
363 * in which case the hunk removes the first
364 * line in the file.
366 state->lost_bucket = &state->sline[state->nb];
367 if (!state->nb)
368 state->nb = 1;
369 } else {
370 state->lost_bucket = &state->sline[state->nb-1];
372 if (!state->sline[state->nb-1].p_lno)
373 state->sline[state->nb-1].p_lno =
374 xcalloc(state->num_parent,
375 sizeof(unsigned long));
376 state->sline[state->nb-1].p_lno[state->n] = state->ob;
377 return;
379 if (!state->lost_bucket)
380 return; /* not in any hunk yet */
381 switch (line[0]) {
382 case '-':
383 append_lost(state->lost_bucket, state->n, line+1, len-1);
384 break;
385 case '+':
386 state->sline[state->lno-1].flag |= state->nmask;
387 state->lno++;
388 break;
392 static void combine_diff(const unsigned char *parent, unsigned int mode,
393 mmfile_t *result_file,
394 struct sline *sline, unsigned int cnt, int n,
395 int num_parent, int result_deleted,
396 struct userdiff_driver *textconv,
397 const char *path, long flags)
399 unsigned int p_lno, lno;
400 unsigned long nmask = (1UL << n);
401 xpparam_t xpp;
402 xdemitconf_t xecfg;
403 mmfile_t parent_file;
404 struct combine_diff_state state;
405 unsigned long sz;
407 if (result_deleted)
408 return; /* result deleted */
410 parent_file.ptr = grab_blob(parent, mode, &sz, textconv, path);
411 parent_file.size = sz;
412 memset(&xpp, 0, sizeof(xpp));
413 xpp.flags = flags;
414 memset(&xecfg, 0, sizeof(xecfg));
415 memset(&state, 0, sizeof(state));
416 state.nmask = nmask;
417 state.sline = sline;
418 state.lno = 1;
419 state.num_parent = num_parent;
420 state.n = n;
422 xdi_diff_outf(&parent_file, result_file, consume_line, &state,
423 &xpp, &xecfg);
424 free(parent_file.ptr);
426 /* Assign line numbers for this parent.
428 * sline[lno].p_lno[n] records the first line number
429 * (counting from 1) for parent N if the final hunk display
430 * started by showing sline[lno] (possibly showing the lost
431 * lines attached to it first).
433 for (lno = 0, p_lno = 1; lno <= cnt; lno++) {
434 struct lline *ll;
435 sline[lno].p_lno[n] = p_lno;
437 /* Coalesce new lines */
438 if (sline[lno].plost.lost_head) {
439 struct sline *sl = &sline[lno];
440 sl->lost = coalesce_lines(sl->lost, &sl->lenlost,
441 sl->plost.lost_head,
442 sl->plost.len, n, flags);
443 sl->plost.lost_head = sl->plost.lost_tail = NULL;
444 sl->plost.len = 0;
447 /* How many lines would this sline advance the p_lno? */
448 ll = sline[lno].lost;
449 while (ll) {
450 if (ll->parent_map & nmask)
451 p_lno++; /* '-' means parent had it */
452 ll = ll->next;
454 if (lno < cnt && !(sline[lno].flag & nmask))
455 p_lno++; /* no '+' means parent had it */
457 sline[lno].p_lno[n] = p_lno; /* trailer */
460 static unsigned long context = 3;
461 static char combine_marker = '@';
463 static int interesting(struct sline *sline, unsigned long all_mask)
465 /* If some parents lost lines here, or if we have added to
466 * some parent, it is interesting.
468 return ((sline->flag & all_mask) || sline->lost);
471 static unsigned long adjust_hunk_tail(struct sline *sline,
472 unsigned long all_mask,
473 unsigned long hunk_begin,
474 unsigned long i)
476 /* i points at the first uninteresting line. If the last line
477 * of the hunk was interesting only because it has some
478 * deletion, then it is not all that interesting for the
479 * purpose of giving trailing context lines. This is because
480 * we output '-' line and then unmodified sline[i-1] itself in
481 * that case which gives us one extra context line.
483 if ((hunk_begin + 1 <= i) && !(sline[i-1].flag & all_mask))
484 i--;
485 return i;
488 static unsigned long find_next(struct sline *sline,
489 unsigned long mark,
490 unsigned long i,
491 unsigned long cnt,
492 int look_for_uninteresting)
494 /* We have examined up to i-1 and are about to look at i.
495 * Find next interesting or uninteresting line. Here,
496 * "interesting" does not mean interesting(), but marked by
497 * the give_context() function below (i.e. it includes context
498 * lines that are not interesting to interesting() function
499 * that are surrounded by interesting() ones.
501 while (i <= cnt)
502 if (look_for_uninteresting
503 ? !(sline[i].flag & mark)
504 : (sline[i].flag & mark))
505 return i;
506 else
507 i++;
508 return i;
511 static int give_context(struct sline *sline, unsigned long cnt, int num_parent)
513 unsigned long all_mask = (1UL<<num_parent) - 1;
514 unsigned long mark = (1UL<<num_parent);
515 unsigned long no_pre_delete = (2UL<<num_parent);
516 unsigned long i;
518 /* Two groups of interesting lines may have a short gap of
519 * uninteresting lines. Connect such groups to give them a
520 * bit of context.
522 * We first start from what the interesting() function says,
523 * and mark them with "mark", and paint context lines with the
524 * mark. So interesting() would still say false for such context
525 * lines but they are treated as "interesting" in the end.
527 i = find_next(sline, mark, 0, cnt, 0);
528 if (cnt < i)
529 return 0;
531 while (i <= cnt) {
532 unsigned long j = (context < i) ? (i - context) : 0;
533 unsigned long k;
535 /* Paint a few lines before the first interesting line. */
536 while (j < i) {
537 if (!(sline[j].flag & mark))
538 sline[j].flag |= no_pre_delete;
539 sline[j++].flag |= mark;
542 again:
543 /* we know up to i is to be included. where does the
544 * next uninteresting one start?
546 j = find_next(sline, mark, i, cnt, 1);
547 if (cnt < j)
548 break; /* the rest are all interesting */
550 /* lookahead context lines */
551 k = find_next(sline, mark, j, cnt, 0);
552 j = adjust_hunk_tail(sline, all_mask, i, j);
554 if (k < j + context) {
555 /* k is interesting and [j,k) are not, but
556 * paint them interesting because the gap is small.
558 while (j < k)
559 sline[j++].flag |= mark;
560 i = k;
561 goto again;
564 /* j is the first uninteresting line and there is
565 * no overlap beyond it within context lines. Paint
566 * the trailing edge a bit.
568 i = k;
569 k = (j + context < cnt+1) ? j + context : cnt+1;
570 while (j < k)
571 sline[j++].flag |= mark;
573 return 1;
576 static int make_hunks(struct sline *sline, unsigned long cnt,
577 int num_parent, int dense)
579 unsigned long all_mask = (1UL<<num_parent) - 1;
580 unsigned long mark = (1UL<<num_parent);
581 unsigned long i;
582 int has_interesting = 0;
584 for (i = 0; i <= cnt; i++) {
585 if (interesting(&sline[i], all_mask))
586 sline[i].flag |= mark;
587 else
588 sline[i].flag &= ~mark;
590 if (!dense)
591 return give_context(sline, cnt, num_parent);
593 /* Look at each hunk, and if we have changes from only one
594 * parent, or the changes are the same from all but one
595 * parent, mark that uninteresting.
597 i = 0;
598 while (i <= cnt) {
599 unsigned long j, hunk_begin, hunk_end;
600 unsigned long same_diff;
601 while (i <= cnt && !(sline[i].flag & mark))
602 i++;
603 if (cnt < i)
604 break; /* No more interesting hunks */
605 hunk_begin = i;
606 for (j = i + 1; j <= cnt; j++) {
607 if (!(sline[j].flag & mark)) {
608 /* Look beyond the end to see if there
609 * is an interesting line after this
610 * hunk within context span.
612 unsigned long la; /* lookahead */
613 int contin = 0;
614 la = adjust_hunk_tail(sline, all_mask,
615 hunk_begin, j);
616 la = (la + context < cnt + 1) ?
617 (la + context) : cnt + 1;
618 while (la && j <= --la) {
619 if (sline[la].flag & mark) {
620 contin = 1;
621 break;
624 if (!contin)
625 break;
626 j = la;
629 hunk_end = j;
631 /* [i..hunk_end) are interesting. Now is it really
632 * interesting? We check if there are only two versions
633 * and the result matches one of them. That is, we look
634 * at:
635 * (+) line, which records lines added to which parents;
636 * this line appears in the result.
637 * (-) line, which records from what parents the line
638 * was removed; this line does not appear in the result.
639 * then check the set of parents the result has difference
640 * from, from all lines. If there are lines that has
641 * different set of parents that the result has differences
642 * from, that means we have more than two versions.
644 * Even when we have only two versions, if the result does
645 * not match any of the parents, the it should be considered
646 * interesting. In such a case, we would have all '+' line.
647 * After passing the above "two versions" test, that would
648 * appear as "the same set of parents" to be "all parents".
650 same_diff = 0;
651 has_interesting = 0;
652 for (j = i; j < hunk_end && !has_interesting; j++) {
653 unsigned long this_diff = sline[j].flag & all_mask;
654 struct lline *ll = sline[j].lost;
655 if (this_diff) {
656 /* This has some changes. Is it the
657 * same as others?
659 if (!same_diff)
660 same_diff = this_diff;
661 else if (same_diff != this_diff) {
662 has_interesting = 1;
663 break;
666 while (ll && !has_interesting) {
667 /* Lost this line from these parents;
668 * who are they? Are they the same?
670 this_diff = ll->parent_map;
671 if (!same_diff)
672 same_diff = this_diff;
673 else if (same_diff != this_diff) {
674 has_interesting = 1;
676 ll = ll->next;
680 if (!has_interesting && same_diff != all_mask) {
681 /* This hunk is not that interesting after all */
682 for (j = hunk_begin; j < hunk_end; j++)
683 sline[j].flag &= ~mark;
685 i = hunk_end;
688 has_interesting = give_context(sline, cnt, num_parent);
689 return has_interesting;
692 static void show_parent_lno(struct sline *sline, unsigned long l0, unsigned long l1, int n, unsigned long null_context)
694 l0 = sline[l0].p_lno[n];
695 l1 = sline[l1].p_lno[n];
696 printf(" -%lu,%lu", l0, l1-l0-null_context);
699 static int hunk_comment_line(const char *bol)
701 int ch;
703 if (!bol)
704 return 0;
705 ch = *bol & 0xff;
706 return (isalpha(ch) || ch == '_' || ch == '$');
709 static void show_line_to_eol(const char *line, int len, const char *reset)
711 int saw_cr_at_eol = 0;
712 if (len < 0)
713 len = strlen(line);
714 saw_cr_at_eol = (len && line[len-1] == '\r');
716 printf("%.*s%s%s\n", len - saw_cr_at_eol, line,
717 reset,
718 saw_cr_at_eol ? "\r" : "");
721 static void dump_sline(struct sline *sline, const char *line_prefix,
722 unsigned long cnt, int num_parent,
723 int use_color, int result_deleted)
725 unsigned long mark = (1UL<<num_parent);
726 unsigned long no_pre_delete = (2UL<<num_parent);
727 int i;
728 unsigned long lno = 0;
729 const char *c_frag = diff_get_color(use_color, DIFF_FRAGINFO);
730 const char *c_func = diff_get_color(use_color, DIFF_FUNCINFO);
731 const char *c_new = diff_get_color(use_color, DIFF_FILE_NEW);
732 const char *c_old = diff_get_color(use_color, DIFF_FILE_OLD);
733 const char *c_plain = diff_get_color(use_color, DIFF_PLAIN);
734 const char *c_reset = diff_get_color(use_color, DIFF_RESET);
736 if (result_deleted)
737 return; /* result deleted */
739 while (1) {
740 unsigned long hunk_end;
741 unsigned long rlines;
742 const char *hunk_comment = NULL;
743 unsigned long null_context = 0;
745 while (lno <= cnt && !(sline[lno].flag & mark)) {
746 if (hunk_comment_line(sline[lno].bol))
747 hunk_comment = sline[lno].bol;
748 lno++;
750 if (cnt < lno)
751 break;
752 else {
753 for (hunk_end = lno + 1; hunk_end <= cnt; hunk_end++)
754 if (!(sline[hunk_end].flag & mark))
755 break;
757 rlines = hunk_end - lno;
758 if (cnt < hunk_end)
759 rlines--; /* pointing at the last delete hunk */
761 if (!context) {
763 * Even when running with --unified=0, all
764 * lines in the hunk needs to be processed in
765 * the loop below in order to show the
766 * deletion recorded in lost_head. However,
767 * we do not want to show the resulting line
768 * with all blank context markers in such a
769 * case. Compensate.
771 unsigned long j;
772 for (j = lno; j < hunk_end; j++)
773 if (!(sline[j].flag & (mark-1)))
774 null_context++;
775 rlines -= null_context;
778 printf("%s%s", line_prefix, c_frag);
779 for (i = 0; i <= num_parent; i++) putchar(combine_marker);
780 for (i = 0; i < num_parent; i++)
781 show_parent_lno(sline, lno, hunk_end, i, null_context);
782 printf(" +%lu,%lu ", lno+1, rlines);
783 for (i = 0; i <= num_parent; i++) putchar(combine_marker);
785 if (hunk_comment) {
786 int comment_end = 0;
787 for (i = 0; i < 40; i++) {
788 int ch = hunk_comment[i] & 0xff;
789 if (!ch || ch == '\n')
790 break;
791 if (!isspace(ch))
792 comment_end = i;
794 if (comment_end)
795 printf("%s%s %s%s", c_reset,
796 c_plain, c_reset,
797 c_func);
798 for (i = 0; i < comment_end; i++)
799 putchar(hunk_comment[i]);
802 printf("%s\n", c_reset);
803 while (lno < hunk_end) {
804 struct lline *ll;
805 int j;
806 unsigned long p_mask;
807 struct sline *sl = &sline[lno++];
808 ll = (sl->flag & no_pre_delete) ? NULL : sl->lost;
809 while (ll) {
810 printf("%s%s", line_prefix, c_old);
811 for (j = 0; j < num_parent; j++) {
812 if (ll->parent_map & (1UL<<j))
813 putchar('-');
814 else
815 putchar(' ');
817 show_line_to_eol(ll->line, -1, c_reset);
818 ll = ll->next;
820 if (cnt < lno)
821 break;
822 p_mask = 1;
823 fputs(line_prefix, stdout);
824 if (!(sl->flag & (mark-1))) {
826 * This sline was here to hang the
827 * lost lines in front of it.
829 if (!context)
830 continue;
831 fputs(c_plain, stdout);
833 else
834 fputs(c_new, stdout);
835 for (j = 0; j < num_parent; j++) {
836 if (p_mask & sl->flag)
837 putchar('+');
838 else
839 putchar(' ');
840 p_mask <<= 1;
842 show_line_to_eol(sl->bol, sl->len, c_reset);
847 static void reuse_combine_diff(struct sline *sline, unsigned long cnt,
848 int i, int j)
850 /* We have already examined parent j and we know parent i
851 * and parent j are the same, so reuse the combined result
852 * of parent j for parent i.
854 unsigned long lno, imask, jmask;
855 imask = (1UL<<i);
856 jmask = (1UL<<j);
858 for (lno = 0; lno <= cnt; lno++) {
859 struct lline *ll = sline->lost;
860 sline->p_lno[i] = sline->p_lno[j];
861 while (ll) {
862 if (ll->parent_map & jmask)
863 ll->parent_map |= imask;
864 ll = ll->next;
866 if (sline->flag & jmask)
867 sline->flag |= imask;
868 sline++;
870 /* the overall size of the file (sline[cnt]) */
871 sline->p_lno[i] = sline->p_lno[j];
874 static void dump_quoted_path(const char *head,
875 const char *prefix,
876 const char *path,
877 const char *line_prefix,
878 const char *c_meta, const char *c_reset)
880 static struct strbuf buf = STRBUF_INIT;
882 strbuf_reset(&buf);
883 strbuf_addstr(&buf, line_prefix);
884 strbuf_addstr(&buf, c_meta);
885 strbuf_addstr(&buf, head);
886 quote_two_c_style(&buf, prefix, path, 0);
887 strbuf_addstr(&buf, c_reset);
888 puts(buf.buf);
891 static void show_combined_header(struct combine_diff_path *elem,
892 int num_parent,
893 int dense,
894 struct rev_info *rev,
895 const char *line_prefix,
896 int mode_differs,
897 int show_file_header)
899 struct diff_options *opt = &rev->diffopt;
900 int abbrev = DIFF_OPT_TST(opt, FULL_INDEX) ? 40 : DEFAULT_ABBREV;
901 const char *a_prefix = opt->a_prefix ? opt->a_prefix : "a/";
902 const char *b_prefix = opt->b_prefix ? opt->b_prefix : "b/";
903 const char *c_meta = diff_get_color_opt(opt, DIFF_METAINFO);
904 const char *c_reset = diff_get_color_opt(opt, DIFF_RESET);
905 const char *abb;
906 int added = 0;
907 int deleted = 0;
908 int i;
910 if (rev->loginfo && !rev->no_commit_id)
911 show_log(rev);
913 dump_quoted_path(dense ? "diff --cc " : "diff --combined ",
914 "", elem->path, line_prefix, c_meta, c_reset);
915 printf("%s%sindex ", line_prefix, c_meta);
916 for (i = 0; i < num_parent; i++) {
917 abb = find_unique_abbrev(elem->parent[i].sha1,
918 abbrev);
919 printf("%s%s", i ? "," : "", abb);
921 abb = find_unique_abbrev(elem->sha1, abbrev);
922 printf("..%s%s\n", abb, c_reset);
924 if (mode_differs) {
925 deleted = !elem->mode;
927 /* We say it was added if nobody had it */
928 added = !deleted;
929 for (i = 0; added && i < num_parent; i++)
930 if (elem->parent[i].status !=
931 DIFF_STATUS_ADDED)
932 added = 0;
933 if (added)
934 printf("%s%snew file mode %06o",
935 line_prefix, c_meta, elem->mode);
936 else {
937 if (deleted)
938 printf("%s%sdeleted file ",
939 line_prefix, c_meta);
940 printf("mode ");
941 for (i = 0; i < num_parent; i++) {
942 printf("%s%06o", i ? "," : "",
943 elem->parent[i].mode);
945 if (elem->mode)
946 printf("..%06o", elem->mode);
948 printf("%s\n", c_reset);
951 if (!show_file_header)
952 return;
954 if (added)
955 dump_quoted_path("--- ", "", "/dev/null",
956 line_prefix, c_meta, c_reset);
957 else
958 dump_quoted_path("--- ", a_prefix, elem->path,
959 line_prefix, c_meta, c_reset);
960 if (deleted)
961 dump_quoted_path("+++ ", "", "/dev/null",
962 line_prefix, c_meta, c_reset);
963 else
964 dump_quoted_path("+++ ", b_prefix, elem->path,
965 line_prefix, c_meta, c_reset);
968 static void show_patch_diff(struct combine_diff_path *elem, int num_parent,
969 int dense, int working_tree_file,
970 struct rev_info *rev)
972 struct diff_options *opt = &rev->diffopt;
973 unsigned long result_size, cnt, lno;
974 int result_deleted = 0;
975 char *result, *cp;
976 struct sline *sline; /* survived lines */
977 int mode_differs = 0;
978 int i, show_hunks;
979 mmfile_t result_file;
980 struct userdiff_driver *userdiff;
981 struct userdiff_driver *textconv = NULL;
982 int is_binary;
983 const char *line_prefix = diff_line_prefix(opt);
985 context = opt->context;
986 userdiff = userdiff_find_by_path(elem->path);
987 if (!userdiff)
988 userdiff = userdiff_find_by_name("default");
989 if (DIFF_OPT_TST(opt, ALLOW_TEXTCONV))
990 textconv = userdiff_get_textconv(userdiff);
992 /* Read the result of merge first */
993 if (!working_tree_file)
994 result = grab_blob(elem->sha1, elem->mode, &result_size,
995 textconv, elem->path);
996 else {
997 /* Used by diff-tree to read from the working tree */
998 struct stat st;
999 int fd = -1;
1001 if (lstat(elem->path, &st) < 0)
1002 goto deleted_file;
1004 if (S_ISLNK(st.st_mode)) {
1005 struct strbuf buf = STRBUF_INIT;
1007 if (strbuf_readlink(&buf, elem->path, st.st_size) < 0) {
1008 error("readlink(%s): %s", elem->path,
1009 strerror(errno));
1010 return;
1012 result_size = buf.len;
1013 result = strbuf_detach(&buf, NULL);
1014 elem->mode = canon_mode(st.st_mode);
1015 } else if (S_ISDIR(st.st_mode)) {
1016 unsigned char sha1[20];
1017 if (resolve_gitlink_ref(elem->path, "HEAD", sha1) < 0)
1018 result = grab_blob(elem->sha1, elem->mode,
1019 &result_size, NULL, NULL);
1020 else
1021 result = grab_blob(sha1, elem->mode,
1022 &result_size, NULL, NULL);
1023 } else if (textconv) {
1024 struct diff_filespec *df = alloc_filespec(elem->path);
1025 fill_filespec(df, null_sha1, 0, st.st_mode);
1026 result_size = fill_textconv(textconv, df, &result);
1027 free_filespec(df);
1028 } else if (0 <= (fd = open(elem->path, O_RDONLY))) {
1029 size_t len = xsize_t(st.st_size);
1030 ssize_t done;
1031 int is_file, i;
1033 elem->mode = canon_mode(st.st_mode);
1034 /* if symlinks don't work, assume symlink if all parents
1035 * are symlinks
1037 is_file = has_symlinks;
1038 for (i = 0; !is_file && i < num_parent; i++)
1039 is_file = !S_ISLNK(elem->parent[i].mode);
1040 if (!is_file)
1041 elem->mode = canon_mode(S_IFLNK);
1043 result_size = len;
1044 result = xmalloc(len + 1);
1046 done = read_in_full(fd, result, len);
1047 if (done < 0)
1048 die_errno("read error '%s'", elem->path);
1049 else if (done < len)
1050 die("early EOF '%s'", elem->path);
1052 result[len] = 0;
1054 /* If not a fake symlink, apply filters, e.g. autocrlf */
1055 if (is_file) {
1056 struct strbuf buf = STRBUF_INIT;
1058 if (convert_to_git(elem->path, result, len, &buf, safe_crlf)) {
1059 free(result);
1060 result = strbuf_detach(&buf, &len);
1061 result_size = len;
1065 else {
1066 deleted_file:
1067 result_deleted = 1;
1068 result_size = 0;
1069 elem->mode = 0;
1070 result = xcalloc(1, 1);
1073 if (0 <= fd)
1074 close(fd);
1077 for (i = 0; i < num_parent; i++) {
1078 if (elem->parent[i].mode != elem->mode) {
1079 mode_differs = 1;
1080 break;
1084 if (textconv)
1085 is_binary = 0;
1086 else if (userdiff->binary != -1)
1087 is_binary = userdiff->binary;
1088 else {
1089 is_binary = buffer_is_binary(result, result_size);
1090 for (i = 0; !is_binary && i < num_parent; i++) {
1091 char *buf;
1092 unsigned long size;
1093 buf = grab_blob(elem->parent[i].sha1,
1094 elem->parent[i].mode,
1095 &size, NULL, NULL);
1096 if (buffer_is_binary(buf, size))
1097 is_binary = 1;
1098 free(buf);
1101 if (is_binary) {
1102 show_combined_header(elem, num_parent, dense, rev,
1103 line_prefix, mode_differs, 0);
1104 printf("Binary files differ\n");
1105 free(result);
1106 return;
1109 for (cnt = 0, cp = result; cp < result + result_size; cp++) {
1110 if (*cp == '\n')
1111 cnt++;
1113 if (result_size && result[result_size-1] != '\n')
1114 cnt++; /* incomplete line */
1116 sline = xcalloc(cnt+2, sizeof(*sline));
1117 sline[0].bol = result;
1118 for (lno = 0, cp = result; cp < result + result_size; cp++) {
1119 if (*cp == '\n') {
1120 sline[lno].len = cp - sline[lno].bol;
1121 lno++;
1122 if (lno < cnt)
1123 sline[lno].bol = cp + 1;
1126 if (result_size && result[result_size-1] != '\n')
1127 sline[cnt-1].len = result_size - (sline[cnt-1].bol - result);
1129 result_file.ptr = result;
1130 result_file.size = result_size;
1132 /* Even p_lno[cnt+1] is valid -- that is for the end line number
1133 * for deletion hunk at the end.
1135 sline[0].p_lno = xcalloc((cnt+2) * num_parent, sizeof(unsigned long));
1136 for (lno = 0; lno <= cnt; lno++)
1137 sline[lno+1].p_lno = sline[lno].p_lno + num_parent;
1139 for (i = 0; i < num_parent; i++) {
1140 int j;
1141 for (j = 0; j < i; j++) {
1142 if (!hashcmp(elem->parent[i].sha1,
1143 elem->parent[j].sha1)) {
1144 reuse_combine_diff(sline, cnt, i, j);
1145 break;
1148 if (i <= j)
1149 combine_diff(elem->parent[i].sha1,
1150 elem->parent[i].mode,
1151 &result_file, sline,
1152 cnt, i, num_parent, result_deleted,
1153 textconv, elem->path, opt->xdl_opts);
1156 show_hunks = make_hunks(sline, cnt, num_parent, dense);
1158 if (show_hunks || mode_differs || working_tree_file) {
1159 show_combined_header(elem, num_parent, dense, rev,
1160 line_prefix, mode_differs, 1);
1161 dump_sline(sline, line_prefix, cnt, num_parent,
1162 opt->use_color, result_deleted);
1164 free(result);
1166 for (lno = 0; lno < cnt; lno++) {
1167 if (sline[lno].lost) {
1168 struct lline *ll = sline[lno].lost;
1169 while (ll) {
1170 struct lline *tmp = ll;
1171 ll = ll->next;
1172 free(tmp);
1176 free(sline[0].p_lno);
1177 free(sline);
1180 static void show_raw_diff(struct combine_diff_path *p, int num_parent, struct rev_info *rev)
1182 struct diff_options *opt = &rev->diffopt;
1183 int line_termination, inter_name_termination, i;
1184 const char *line_prefix = diff_line_prefix(opt);
1186 line_termination = opt->line_termination;
1187 inter_name_termination = '\t';
1188 if (!line_termination)
1189 inter_name_termination = 0;
1191 if (rev->loginfo && !rev->no_commit_id)
1192 show_log(rev);
1195 if (opt->output_format & DIFF_FORMAT_RAW) {
1196 printf("%s", line_prefix);
1198 /* As many colons as there are parents */
1199 for (i = 0; i < num_parent; i++)
1200 putchar(':');
1202 /* Show the modes */
1203 for (i = 0; i < num_parent; i++)
1204 printf("%06o ", p->parent[i].mode);
1205 printf("%06o", p->mode);
1207 /* Show sha1's */
1208 for (i = 0; i < num_parent; i++)
1209 printf(" %s", diff_unique_abbrev(p->parent[i].sha1,
1210 opt->abbrev));
1211 printf(" %s ", diff_unique_abbrev(p->sha1, opt->abbrev));
1214 if (opt->output_format & (DIFF_FORMAT_RAW | DIFF_FORMAT_NAME_STATUS)) {
1215 for (i = 0; i < num_parent; i++)
1216 putchar(p->parent[i].status);
1217 putchar(inter_name_termination);
1220 write_name_quoted(p->path, stdout, line_termination);
1224 * The result (p->elem) is from the working tree and their
1225 * parents are typically from multiple stages during a merge
1226 * (i.e. diff-files) or the state in HEAD and in the index
1227 * (i.e. diff-index).
1229 void show_combined_diff(struct combine_diff_path *p,
1230 int num_parent,
1231 int dense,
1232 struct rev_info *rev)
1234 struct diff_options *opt = &rev->diffopt;
1236 if (opt->output_format & (DIFF_FORMAT_RAW |
1237 DIFF_FORMAT_NAME |
1238 DIFF_FORMAT_NAME_STATUS))
1239 show_raw_diff(p, num_parent, rev);
1240 else if (opt->output_format & DIFF_FORMAT_PATCH)
1241 show_patch_diff(p, num_parent, dense, 1, rev);
1244 static void free_combined_pair(struct diff_filepair *pair)
1246 free(pair->two);
1247 free(pair);
1251 * A combine_diff_path expresses N parents on the LHS against 1 merge
1252 * result. Synthesize a diff_filepair that has N entries on the "one"
1253 * side and 1 entry on the "two" side.
1255 * In the future, we might want to add more data to combine_diff_path
1256 * so that we can fill fields we are ignoring (most notably, size) here,
1257 * but currently nobody uses it, so this should suffice for now.
1259 static struct diff_filepair *combined_pair(struct combine_diff_path *p,
1260 int num_parent)
1262 int i;
1263 struct diff_filepair *pair;
1264 struct diff_filespec *pool;
1266 pair = xmalloc(sizeof(*pair));
1267 pool = xcalloc(num_parent + 1, sizeof(struct diff_filespec));
1268 pair->one = pool + 1;
1269 pair->two = pool;
1271 for (i = 0; i < num_parent; i++) {
1272 pair->one[i].path = p->path;
1273 pair->one[i].mode = p->parent[i].mode;
1274 hashcpy(pair->one[i].sha1, p->parent[i].sha1);
1275 pair->one[i].sha1_valid = !is_null_sha1(p->parent[i].sha1);
1276 pair->one[i].has_more_entries = 1;
1278 pair->one[num_parent - 1].has_more_entries = 0;
1280 pair->two->path = p->path;
1281 pair->two->mode = p->mode;
1282 hashcpy(pair->two->sha1, p->sha1);
1283 pair->two->sha1_valid = !is_null_sha1(p->sha1);
1284 return pair;
1287 static void handle_combined_callback(struct diff_options *opt,
1288 struct combine_diff_path *paths,
1289 int num_parent,
1290 int num_paths)
1292 struct combine_diff_path *p;
1293 struct diff_queue_struct q;
1294 int i;
1296 q.queue = xcalloc(num_paths, sizeof(struct diff_filepair *));
1297 q.alloc = num_paths;
1298 q.nr = num_paths;
1299 for (i = 0, p = paths; p; p = p->next)
1300 q.queue[i++] = combined_pair(p, num_parent);
1301 opt->format_callback(&q, opt, opt->format_callback_data);
1302 for (i = 0; i < num_paths; i++)
1303 free_combined_pair(q.queue[i]);
1304 free(q.queue);
1307 static const char *path_path(void *obj)
1309 struct combine_diff_path *path = (struct combine_diff_path *)obj;
1311 return path->path;
1315 /* find set of paths that every parent touches */
1316 static struct combine_diff_path *find_paths_generic(const unsigned char *sha1,
1317 const struct sha1_array *parents, struct diff_options *opt)
1319 struct combine_diff_path *paths = NULL;
1320 int i, num_parent = parents->nr;
1322 int output_format = opt->output_format;
1323 const char *orderfile = opt->orderfile;
1325 opt->output_format = DIFF_FORMAT_NO_OUTPUT;
1326 /* tell diff_tree to emit paths in sorted (=tree) order */
1327 opt->orderfile = NULL;
1329 /* D(A,P1...Pn) = D(A,P1) ^ ... ^ D(A,Pn) (wrt paths) */
1330 for (i = 0; i < num_parent; i++) {
1332 * show stat against the first parent even when doing
1333 * combined diff.
1335 int stat_opt = (output_format &
1336 (DIFF_FORMAT_NUMSTAT|DIFF_FORMAT_DIFFSTAT));
1337 if (i == 0 && stat_opt)
1338 opt->output_format = stat_opt;
1339 else
1340 opt->output_format = DIFF_FORMAT_NO_OUTPUT;
1341 diff_tree_sha1(parents->sha1[i], sha1, "", opt);
1342 diffcore_std(opt);
1343 paths = intersect_paths(paths, i, num_parent);
1345 /* if showing diff, show it in requested order */
1346 if (opt->output_format != DIFF_FORMAT_NO_OUTPUT &&
1347 orderfile) {
1348 diffcore_order(orderfile);
1351 diff_flush(opt);
1354 opt->output_format = output_format;
1355 opt->orderfile = orderfile;
1356 return paths;
1361 * find set of paths that everybody touches, assuming diff is run without
1362 * rename/copy detection, etc, comparing all trees simultaneously (= faster).
1364 static struct combine_diff_path *find_paths_multitree(
1365 const unsigned char *sha1, const struct sha1_array *parents,
1366 struct diff_options *opt)
1368 int i, nparent = parents->nr;
1369 const unsigned char **parents_sha1;
1370 struct combine_diff_path paths_head;
1371 struct strbuf base;
1373 parents_sha1 = xmalloc(nparent * sizeof(parents_sha1[0]));
1374 for (i = 0; i < nparent; i++)
1375 parents_sha1[i] = parents->sha1[i];
1377 /* fake list head, so worker can assume it is non-NULL */
1378 paths_head.next = NULL;
1380 strbuf_init(&base, PATH_MAX);
1381 diff_tree_paths(&paths_head, sha1, parents_sha1, nparent, &base, opt);
1383 strbuf_release(&base);
1384 free(parents_sha1);
1385 return paths_head.next;
1389 void diff_tree_combined(const unsigned char *sha1,
1390 const struct sha1_array *parents,
1391 int dense,
1392 struct rev_info *rev)
1394 struct diff_options *opt = &rev->diffopt;
1395 struct diff_options diffopts;
1396 struct combine_diff_path *p, *paths;
1397 int i, num_paths, needsep, show_log_first, num_parent = parents->nr;
1398 int need_generic_pathscan;
1400 /* nothing to do, if no parents */
1401 if (!num_parent)
1402 return;
1404 show_log_first = !!rev->loginfo && !rev->no_commit_id;
1405 needsep = 0;
1406 if (show_log_first) {
1407 show_log(rev);
1409 if (rev->verbose_header && opt->output_format &&
1410 opt->output_format != DIFF_FORMAT_NO_OUTPUT &&
1411 !commit_format_is_empty(rev->commit_format))
1412 printf("%s%c", diff_line_prefix(opt),
1413 opt->line_termination);
1416 diffopts = *opt;
1417 copy_pathspec(&diffopts.pathspec, &opt->pathspec);
1418 DIFF_OPT_SET(&diffopts, RECURSIVE);
1419 DIFF_OPT_CLR(&diffopts, ALLOW_EXTERNAL);
1421 /* find set of paths that everybody touches
1423 * NOTE
1425 * Diffcore transformations are bound to diff_filespec and logic
1426 * comparing two entries - i.e. they do not apply directly to combine
1427 * diff.
1429 * If some of such transformations is requested - we launch generic
1430 * path scanning, which works significantly slower compared to
1431 * simultaneous all-trees-in-one-go scan in find_paths_multitree().
1433 * TODO some of the filters could be ported to work on
1434 * combine_diff_paths - i.e. all functionality that skips paths, so in
1435 * theory, we could end up having only multitree path scanning.
1437 * NOTE please keep this semantically in sync with diffcore_std()
1439 need_generic_pathscan = opt->skip_stat_unmatch ||
1440 DIFF_OPT_TST(opt, FOLLOW_RENAMES) ||
1441 opt->break_opt != -1 ||
1442 opt->detect_rename ||
1443 opt->pickaxe ||
1444 opt->filter;
1447 if (need_generic_pathscan) {
1449 * NOTE generic case also handles --stat, as it computes
1450 * diff(sha1,parent_i) for all i to do the job, specifically
1451 * for parent0.
1453 paths = find_paths_generic(sha1, parents, &diffopts);
1455 else {
1456 int stat_opt;
1457 paths = find_paths_multitree(sha1, parents, &diffopts);
1460 * show stat against the first parent even
1461 * when doing combined diff.
1463 stat_opt = (opt->output_format &
1464 (DIFF_FORMAT_NUMSTAT|DIFF_FORMAT_DIFFSTAT));
1465 if (stat_opt) {
1466 diffopts.output_format = stat_opt;
1468 diff_tree_sha1(parents->sha1[0], sha1, "", &diffopts);
1469 diffcore_std(&diffopts);
1470 if (opt->orderfile)
1471 diffcore_order(opt->orderfile);
1472 diff_flush(&diffopts);
1476 /* find out number of surviving paths */
1477 for (num_paths = 0, p = paths; p; p = p->next)
1478 num_paths++;
1480 /* order paths according to diffcore_order */
1481 if (opt->orderfile && num_paths) {
1482 struct obj_order *o;
1484 o = xmalloc(sizeof(*o) * num_paths);
1485 for (i = 0, p = paths; p; p = p->next, i++)
1486 o[i].obj = p;
1487 order_objects(opt->orderfile, path_path, o, num_paths);
1488 for (i = 0; i < num_paths - 1; i++) {
1489 p = o[i].obj;
1490 p->next = o[i+1].obj;
1493 p = o[num_paths-1].obj;
1494 p->next = NULL;
1495 paths = o[0].obj;
1496 free(o);
1500 if (num_paths) {
1501 if (opt->output_format & (DIFF_FORMAT_RAW |
1502 DIFF_FORMAT_NAME |
1503 DIFF_FORMAT_NAME_STATUS)) {
1504 for (p = paths; p; p = p->next)
1505 show_raw_diff(p, num_parent, rev);
1506 needsep = 1;
1508 else if (opt->output_format &
1509 (DIFF_FORMAT_NUMSTAT|DIFF_FORMAT_DIFFSTAT))
1510 needsep = 1;
1511 else if (opt->output_format & DIFF_FORMAT_CALLBACK)
1512 handle_combined_callback(opt, paths, num_parent, num_paths);
1514 if (opt->output_format & DIFF_FORMAT_PATCH) {
1515 if (needsep)
1516 printf("%s%c", diff_line_prefix(opt),
1517 opt->line_termination);
1518 for (p = paths; p; p = p->next)
1519 show_patch_diff(p, num_parent, dense,
1520 0, rev);
1524 /* Clean things up */
1525 while (paths) {
1526 struct combine_diff_path *tmp = paths;
1527 paths = paths->next;
1528 free(tmp);
1531 free_pathspec(&diffopts.pathspec);
1534 void diff_tree_combined_merge(const struct commit *commit, int dense,
1535 struct rev_info *rev)
1537 struct commit_list *parent = get_saved_parents(rev, commit);
1538 struct sha1_array parents = SHA1_ARRAY_INIT;
1540 while (parent) {
1541 sha1_array_append(&parents, parent->item->object.sha1);
1542 parent = parent->next;
1544 diff_tree_combined(commit->object.sha1, &parents, dense, rev);
1545 sha1_array_clear(&parents);