7 #include "xdiff-interface.h"
9 static int uninteresting(struct diff_filepair *p)
11 if (diff_unmodified_pair(p))
16 static struct combine_diff_path *intersect_paths(struct combine_diff_path *curr, int n, int num_parent)
18 struct diff_queue_struct *q = &diff_queued_diff;
19 struct combine_diff_path *p;
23 struct combine_diff_path *list = NULL, **tail = &list;
24 for (i = 0; i < q->nr; i++) {
27 if (uninteresting(q->queue[i]))
29 path = q->queue[i]->two->path;
31 p = xmalloc(combine_diff_path_size(num_parent, len));
32 p->path = (char*) &(p->parent[num_parent]);
33 memcpy(p->path, path, len);
38 sizeof(p->parent[0]) * num_parent);
40 memcpy(p->sha1, q->queue[i]->two->sha1, 20);
41 p->mode = q->queue[i]->two->mode;
42 memcpy(p->parent[n].sha1, q->queue[i]->one->sha1, 20);
43 p->parent[n].mode = q->queue[i]->one->mode;
44 p->parent[n].status = q->queue[i]->status;
51 for (p = curr; p; p = p->next) {
55 for (i = 0; i < q->nr; i++) {
59 if (uninteresting(q->queue[i]))
61 path = q->queue[i]->two->path;
63 if (len == p->len && !memcmp(path, p->path, len)) {
65 memcpy(p->parent[n].sha1,
66 q->queue[i]->one->sha1, 20);
67 p->parent[n].mode = q->queue[i]->one->mode;
68 p->parent[n].status = q->queue[i]->status;
78 /* Lines lost from parent */
82 unsigned long parent_map;
83 char line[FLEX_ARRAY];
86 /* Lines surviving in the merge result */
88 struct lline *lost_head, **lost_tail;
91 /* bit 0 up to (N-1) are on if the parent has this line (i.e.
92 * we did not change it).
93 * bit N is used for "interesting" lines, including context.
99 static char *grab_blob(const unsigned char *sha1, unsigned long *size)
103 if (!memcmp(sha1, null_sha1, 20)) {
106 return xcalloc(1, 1);
108 blob = read_sha1_file(sha1, type, size);
109 if (strcmp(type, blob_type))
110 die("object '%s' is not a blob!", sha1_to_hex(sha1));
114 static void append_lost(struct sline *sline, int n, const char *line, int len)
117 unsigned long this_mask = (1UL<<n);
118 if (line[len-1] == '\n')
121 /* Check to see if we can squash things */
122 if (sline->lost_head) {
123 struct lline *last_one = NULL;
124 /* We cannot squash it with earlier one */
125 for (lline = sline->lost_head;
128 if (lline->parent_map & this_mask)
130 lline = last_one ? last_one->next : sline->lost_head;
132 if (lline->len == len &&
133 !memcmp(lline->line, line, len)) {
134 lline->parent_map |= this_mask;
141 lline = xmalloc(sizeof(*lline) + len + 1);
144 lline->parent_map = this_mask;
145 memcpy(lline->line, line, len);
146 lline->line[len] = 0;
147 *sline->lost_tail = lline;
148 sline->lost_tail = &lline->next;
151 struct combine_diff_state {
152 struct xdiff_emit_state xm;
154 unsigned int lno, ob, on, nb, nn;
159 struct sline *lost_bucket;
162 static void consume_line(void *state_, char *line, unsigned long len)
164 struct combine_diff_state *state = state_;
165 if (5 < len && !memcmp("@@ -", line, 4)) {
166 if (parse_hunk_header(line, len,
167 &state->ob, &state->on,
168 &state->nb, &state->nn))
170 state->lno = state->nb;
172 /* @@ -1,2 +0,0 @@ to remove the
177 /* @@ -X,Y +N,0 @@ removed Y lines
178 * that would have come *after* line N
179 * in the result. Our lost buckets hang
180 * to the line after the removed lines,
182 state->lost_bucket = &state->sline[state->nb];
184 state->lost_bucket = &state->sline[state->nb-1];
185 if (!state->sline[state->nb-1].p_lno)
186 state->sline[state->nb-1].p_lno =
187 xcalloc(state->num_parent,
188 sizeof(unsigned long));
189 state->sline[state->nb-1].p_lno[state->n] = state->ob;
192 if (!state->lost_bucket)
193 return; /* not in any hunk yet */
196 append_lost(state->lost_bucket, state->n, line+1, len-1);
199 state->sline[state->lno-1].flag |= state->nmask;
205 static void combine_diff(const unsigned char *parent, mmfile_t *result_file,
206 struct sline *sline, int cnt, int n, int num_parent)
208 unsigned int p_lno, lno;
209 unsigned long nmask = (1UL << n);
212 mmfile_t parent_file;
214 struct combine_diff_state state;
218 return; /* result deleted */
220 parent_file.ptr = grab_blob(parent, &sz);
221 parent_file.size = sz;
222 xpp.flags = XDF_NEED_MINIMAL;
225 ecb.outf = xdiff_outf;
227 memset(&state, 0, sizeof(state));
228 state.xm.consume = consume_line;
232 state.num_parent = num_parent;
235 xdl_diff(&parent_file, result_file, &xpp, &xecfg, &ecb);
236 free(parent_file.ptr);
238 /* Assign line numbers for this parent.
240 * sline[lno].p_lno[n] records the first line number
241 * (counting from 1) for parent N if the final hunk display
242 * started by showing sline[lno] (possibly showing the lost
243 * lines attached to it first).
245 for (lno = 0, p_lno = 1; lno < cnt; lno++) {
247 sline[lno].p_lno[n] = p_lno;
249 /* How many lines would this sline advance the p_lno? */
250 ll = sline[lno].lost_head;
252 if (ll->parent_map & nmask)
253 p_lno++; /* '-' means parent had it */
256 if (!(sline[lno].flag & nmask))
257 p_lno++; /* no '+' means parent had it */
259 sline[lno].p_lno[n] = p_lno; /* trailer */
262 static unsigned long context = 3;
263 static char combine_marker = '@';
265 static int interesting(struct sline *sline, unsigned long all_mask)
267 /* If some parents lost lines here, or if we have added to
268 * some parent, it is interesting.
270 return ((sline->flag & all_mask) || sline->lost_head);
273 static unsigned long adjust_hunk_tail(struct sline *sline,
274 unsigned long all_mask,
275 unsigned long hunk_begin,
278 /* i points at the first uninteresting line. If the last line
279 * of the hunk was interesting only because it has some
280 * deletion, then it is not all that interesting for the
281 * purpose of giving trailing context lines. This is because
282 * we output '-' line and then unmodified sline[i-1] itself in
283 * that case which gives us one extra context line.
285 if ((hunk_begin + 1 <= i) && !(sline[i-1].flag & all_mask))
290 static unsigned long find_next(struct sline *sline,
296 /* We have examined up to i-1 and are about to look at i.
297 * Find next interesting or uninteresting line. Here,
298 * "interesting" does not mean interesting(), but marked by
299 * the give_context() function below (i.e. it includes context
300 * lines that are not interesting to interesting() function
301 * that are surrounded by interesting() ones.
305 ? !(sline[i].flag & mark)
306 : (sline[i].flag & mark))
313 static int give_context(struct sline *sline, unsigned long cnt, int num_parent)
315 unsigned long all_mask = (1UL<<num_parent) - 1;
316 unsigned long mark = (1UL<<num_parent);
319 /* Two groups of interesting lines may have a short gap of
320 * unintersting lines. Connect such groups to give them a
323 * We first start from what the interesting() function says,
324 * and mark them with "mark", and paint context lines with the
325 * mark. So interesting() would still say false for such context
326 * lines but they are treated as "interesting" in the end.
328 i = find_next(sline, mark, 0, cnt, 0);
333 unsigned long j = (context < i) ? (i - context) : 0;
336 /* Paint a few lines before the first interesting line. */
338 sline[j++].flag |= mark;
341 /* we know up to i is to be included. where does the
342 * next uninteresting one start?
344 j = find_next(sline, mark, i, cnt, 1);
346 break; /* the rest are all interesting */
348 /* lookahead context lines */
349 k = find_next(sline, mark, j, cnt, 0);
350 j = adjust_hunk_tail(sline, all_mask, i, j);
352 if (k < j + context) {
353 /* k is interesting and [j,k) are not, but
354 * paint them interesting because the gap is small.
357 sline[j++].flag |= mark;
362 /* j is the first uninteresting line and there is
363 * no overlap beyond it within context lines. Paint
364 * the trailing edge a bit.
367 k = (j + context < cnt) ? j + context : cnt;
369 sline[j++].flag |= mark;
374 static int make_hunks(struct sline *sline, unsigned long cnt,
375 int num_parent, int dense)
377 unsigned long all_mask = (1UL<<num_parent) - 1;
378 unsigned long mark = (1UL<<num_parent);
380 int has_interesting = 0;
382 for (i = 0; i < cnt; i++) {
383 if (interesting(&sline[i], all_mask))
384 sline[i].flag |= mark;
386 sline[i].flag &= ~mark;
389 return give_context(sline, cnt, num_parent);
391 /* Look at each hunk, and if we have changes from only one
392 * parent, or the changes are the same from all but one
393 * parent, mark that uninteresting.
397 unsigned long j, hunk_begin, hunk_end;
398 unsigned long same_diff;
399 while (i < cnt && !(sline[i].flag & mark))
402 break; /* No more interesting hunks */
404 for (j = i + 1; j < cnt; j++) {
405 if (!(sline[j].flag & mark)) {
406 /* Look beyond the end to see if there
407 * is an interesting line after this
408 * hunk within context span.
410 unsigned long la; /* lookahead */
412 la = adjust_hunk_tail(sline, all_mask,
414 la = (la + context < cnt) ?
415 (la + context) : cnt;
417 if (sline[la].flag & mark) {
429 /* [i..hunk_end) are interesting. Now is it really
430 * interesting? We check if there are only two versions
431 * and the result matches one of them. That is, we look
433 * (+) line, which records lines added to which parents;
434 * this line appears in the result.
435 * (-) line, which records from what parents the line
436 * was removed; this line does not appear in the result.
437 * then check the set of parents the result has difference
438 * from, from all lines. If there are lines that has
439 * different set of parents that the result has differences
440 * from, that means we have more than two versions.
442 * Even when we have only two versions, if the result does
443 * not match any of the parents, the it should be considered
444 * interesting. In such a case, we would have all '+' line.
445 * After passing the above "two versions" test, that would
446 * appear as "the same set of parents" to be "all parents".
450 for (j = i; j < hunk_end && !has_interesting; j++) {
451 unsigned long this_diff = sline[j].flag & all_mask;
452 struct lline *ll = sline[j].lost_head;
454 /* This has some changes. Is it the
458 same_diff = this_diff;
459 else if (same_diff != this_diff) {
464 while (ll && !has_interesting) {
465 /* Lost this line from these parents;
466 * who are they? Are they the same?
468 this_diff = ll->parent_map;
470 same_diff = this_diff;
471 else if (same_diff != this_diff) {
478 if (!has_interesting && same_diff != all_mask) {
479 /* This hunk is not that interesting after all */
480 for (j = hunk_begin; j < hunk_end; j++)
481 sline[j].flag &= ~mark;
486 has_interesting = give_context(sline, cnt, num_parent);
487 return has_interesting;
490 static void show_parent_lno(struct sline *sline, unsigned long l0, unsigned long l1, unsigned long cnt, int n)
492 l0 = sline[l0].p_lno[n];
493 l1 = sline[l1].p_lno[n];
494 printf(" -%lu,%lu", l0, l1-l0);
497 static void dump_sline(struct sline *sline, unsigned long cnt, int num_parent)
499 unsigned long mark = (1UL<<num_parent);
501 unsigned long lno = 0;
504 return; /* result deleted */
507 struct sline *sl = &sline[lno];
509 while (lno < cnt && !(sline[lno].flag & mark))
513 for (hunk_end = lno + 1; hunk_end < cnt; hunk_end++)
514 if (!(sline[hunk_end].flag & mark))
516 for (i = 0; i <= num_parent; i++) putchar(combine_marker);
517 for (i = 0; i < num_parent; i++)
518 show_parent_lno(sline, lno, hunk_end, cnt, i);
519 printf(" +%lu,%lu ", lno+1, hunk_end-lno);
520 for (i = 0; i <= num_parent; i++) putchar(combine_marker);
522 while (lno < hunk_end) {
525 unsigned long p_mask;
529 for (j = 0; j < num_parent; j++) {
530 if (ll->parent_map & (1UL<<j))
539 for (j = 0; j < num_parent; j++) {
540 if (p_mask & sl->flag)
546 printf("%.*s\n", sl->len, sl->bol);
551 static void reuse_combine_diff(struct sline *sline, unsigned long cnt,
554 /* We have already examined parent j and we know parent i
555 * and parent j are the same, so reuse the combined result
556 * of parent j for parent i.
558 unsigned long lno, imask, jmask;
562 for (lno = 0; lno < cnt; lno++) {
563 struct lline *ll = sline->lost_head;
564 sline->p_lno[i] = sline->p_lno[j];
566 if (ll->parent_map & jmask)
567 ll->parent_map |= imask;
570 if (sline->flag & jmask)
571 sline->flag |= imask;
574 /* the overall size of the file (sline[cnt]) */
575 sline->p_lno[i] = sline->p_lno[j];
578 static int show_patch_diff(struct combine_diff_path *elem, int num_parent,
579 int dense, const char *header,
580 struct diff_options *opt)
582 unsigned long result_size, cnt, lno;
583 char *result, *cp, *ep;
584 struct sline *sline; /* survived lines */
585 int mode_differs = 0;
586 int i, show_hunks, shown_header = 0;
587 int working_tree_file = !memcmp(elem->sha1, null_sha1, 20);
588 int abbrev = opt->full_index ? 40 : DEFAULT_ABBREV;
589 mmfile_t result_file;
591 /* Read the result of merge first */
592 if (!working_tree_file)
593 result = grab_blob(elem->sha1, &result_size);
595 /* Used by diff-tree to read from the working tree */
598 if (0 <= (fd = open(elem->path, O_RDONLY)) &&
600 int len = st.st_size;
603 elem->mode = canon_mode(st.st_mode);
605 result = xmalloc(len + 1);
607 int done = xread(fd, result+cnt, len-cnt);
611 die("read error '%s'", elem->path);
627 for (cnt = 0, cp = result; cp - result < result_size; cp++) {
631 if (result_size && result[result_size-1] != '\n')
632 cnt++; /* incomplete line */
634 sline = xcalloc(cnt+1, sizeof(*sline));
636 sline[0].bol = result;
637 for (lno = 0; lno <= cnt; lno++) {
638 sline[lno].lost_tail = &sline[lno].lost_head;
641 for (lno = 0, cp = result; cp - result < result_size; cp++) {
643 sline[lno].len = cp - sline[lno].bol;
646 sline[lno].bol = cp + 1;
649 if (result_size && result[result_size-1] != '\n')
650 sline[cnt-1].len = result_size - (sline[cnt-1].bol - result);
652 result_file.ptr = result;
653 result_file.size = result_size;
655 sline[0].p_lno = xcalloc((cnt+1) * num_parent, sizeof(unsigned long));
656 for (lno = 0; lno < cnt; lno++)
657 sline[lno+1].p_lno = sline[lno].p_lno + num_parent;
659 for (i = 0; i < num_parent; i++) {
661 for (j = 0; j < i; j++) {
662 if (!memcmp(elem->parent[i].sha1,
663 elem->parent[j].sha1, 20)) {
664 reuse_combine_diff(sline, cnt, i, j);
669 combine_diff(elem->parent[i].sha1, &result_file, sline,
671 if (elem->parent[i].mode != elem->mode)
675 show_hunks = make_hunks(sline, cnt, num_parent, dense);
677 if (show_hunks || mode_differs || working_tree_file) {
682 printf("%s%c", header, opt->line_termination);
684 printf("diff --%s ", dense ? "cc" : "combined");
685 if (quote_c_style(elem->path, NULL, NULL, 0))
686 quote_c_style(elem->path, NULL, stdout, 0);
688 printf("%s", elem->path);
691 for (i = 0; i < num_parent; i++) {
692 abb = find_unique_abbrev(elem->parent[i].sha1,
694 printf("%s%s", i ? "," : "", abb);
696 abb = find_unique_abbrev(elem->sha1, abbrev);
697 printf("..%s\n", abb);
700 int added = !!elem->mode;
701 for (i = 0; added && i < num_parent; i++)
702 if (elem->parent[i].status !=
706 printf("new file mode %06o", elem->mode);
709 printf("deleted file ");
711 for (i = 0; i < num_parent; i++) {
712 printf("%s%06o", i ? "," : "",
713 elem->parent[i].mode);
716 printf("..%06o", elem->mode);
720 dump_sline(sline, cnt, num_parent);
724 for (i = 0; i < cnt; i++) {
725 if (sline[i].lost_head) {
726 struct lline *ll = sline[i].lost_head;
728 struct lline *tmp = ll;
734 free(sline[0].p_lno);
739 #define COLONS "::::::::::::::::::::::::::::::::"
741 static void show_raw_diff(struct combine_diff_path *p, int num_parent, const char *header, struct diff_options *opt)
743 int i, offset, mod_type = 'A';
745 int line_termination, inter_name_termination;
747 line_termination = opt->line_termination;
748 inter_name_termination = '\t';
749 if (!line_termination)
750 inter_name_termination = 0;
753 printf("%s%c", header, line_termination);
755 for (i = 0; i < num_parent; i++) {
756 if (p->parent[i].mode)
762 if (opt->output_format == DIFF_FORMAT_RAW) {
763 offset = strlen(COLONS) - num_parent;
766 prefix = COLONS + offset;
769 for (i = 0; i < num_parent; i++) {
770 printf("%s%06o", prefix, p->parent[i].mode);
773 printf("%s%06o", prefix, p->mode);
776 for (i = 0; i < num_parent; i++)
777 printf(" %s", diff_unique_abbrev(p->parent[i].sha1,
779 printf(" %s ", diff_unique_abbrev(p->sha1, opt->abbrev));
782 if (opt->output_format == DIFF_FORMAT_RAW ||
783 opt->output_format == DIFF_FORMAT_NAME_STATUS) {
784 for (i = 0; i < num_parent; i++)
785 putchar(p->parent[i].status);
786 putchar(inter_name_termination);
789 if (line_termination) {
790 if (quote_c_style(p->path, NULL, NULL, 0))
791 quote_c_style(p->path, NULL, stdout, 0);
793 printf("%s", p->path);
794 putchar(line_termination);
797 printf("%s%c", p->path, line_termination);
801 int show_combined_diff(struct combine_diff_path *p,
805 struct diff_options *opt)
809 switch (opt->output_format) {
810 case DIFF_FORMAT_RAW:
811 case DIFF_FORMAT_NAME_STATUS:
812 case DIFF_FORMAT_NAME:
813 show_raw_diff(p, num_parent, header, opt);
817 case DIFF_FORMAT_PATCH:
818 return show_patch_diff(p, num_parent, dense, header, opt);
822 const char *diff_tree_combined_merge(const unsigned char *sha1,
823 const char *header, int dense,
824 struct diff_options *opt)
826 struct commit *commit = lookup_commit(sha1);
827 struct diff_options diffopts;
828 struct commit_list *parents;
829 struct combine_diff_path *p, *paths = NULL;
830 int num_parent, i, num_paths;
833 diffopts.output_format = DIFF_FORMAT_NO_OUTPUT;
834 diffopts.recursive = 1;
837 for (parents = commit->parents, num_parent = 0;
839 parents = parents->next, num_parent++)
842 /* find set of paths that everybody touches */
843 for (parents = commit->parents, i = 0;
845 parents = parents->next, i++) {
846 struct commit *parent = parents->item;
847 diff_tree_sha1(parent->object.sha1, commit->object.sha1, "",
849 diffcore_std(&diffopts);
850 paths = intersect_paths(paths, i, num_parent);
851 diff_flush(&diffopts);
854 /* find out surviving paths */
855 for (num_paths = 0, p = paths; p; p = p->next) {
860 for (p = paths; p; p = p->next) {
861 if (show_combined_diff(p, num_parent, dense,
867 /* Clean things up */
869 struct combine_diff_path *tmp = paths;