7 #include "xdiff-interface.h"
10 static int uninteresting(struct diff_filepair *p)
12 if (diff_unmodified_pair(p))
17 static struct combine_diff_path *intersect_paths(struct combine_diff_path *curr, int n, int num_parent)
19 struct diff_queue_struct *q = &diff_queued_diff;
20 struct combine_diff_path *p;
24 struct combine_diff_path *list = NULL, **tail = &list;
25 for (i = 0; i < q->nr; i++) {
28 if (uninteresting(q->queue[i]))
30 path = q->queue[i]->two->path;
32 p = xmalloc(combine_diff_path_size(num_parent, len));
33 p->path = (char*) &(p->parent[num_parent]);
34 memcpy(p->path, path, len);
39 sizeof(p->parent[0]) * num_parent);
41 memcpy(p->sha1, q->queue[i]->two->sha1, 20);
42 p->mode = q->queue[i]->two->mode;
43 memcpy(p->parent[n].sha1, q->queue[i]->one->sha1, 20);
44 p->parent[n].mode = q->queue[i]->one->mode;
45 p->parent[n].status = q->queue[i]->status;
52 for (p = curr; p; p = p->next) {
56 for (i = 0; i < q->nr; i++) {
60 if (uninteresting(q->queue[i]))
62 path = q->queue[i]->two->path;
64 if (len == p->len && !memcmp(path, p->path, len)) {
66 memcpy(p->parent[n].sha1,
67 q->queue[i]->one->sha1, 20);
68 p->parent[n].mode = q->queue[i]->one->mode;
69 p->parent[n].status = q->queue[i]->status;
79 /* Lines lost from parent */
83 unsigned long parent_map;
84 char line[FLEX_ARRAY];
87 /* Lines surviving in the merge result */
89 struct lline *lost_head, **lost_tail;
92 /* bit 0 up to (N-1) are on if the parent has this line (i.e.
93 * we did not change it).
94 * bit N is used for "interesting" lines, including context.
100 static char *grab_blob(const unsigned char *sha1, unsigned long *size)
104 if (!memcmp(sha1, null_sha1, 20)) {
107 return xcalloc(1, 1);
109 blob = read_sha1_file(sha1, type, size);
110 if (strcmp(type, blob_type))
111 die("object '%s' is not a blob!", sha1_to_hex(sha1));
115 static void append_lost(struct sline *sline, int n, const char *line, int len)
118 unsigned long this_mask = (1UL<<n);
119 if (line[len-1] == '\n')
122 /* Check to see if we can squash things */
123 if (sline->lost_head) {
124 struct lline *last_one = NULL;
125 /* We cannot squash it with earlier one */
126 for (lline = sline->lost_head;
129 if (lline->parent_map & this_mask)
131 lline = last_one ? last_one->next : sline->lost_head;
133 if (lline->len == len &&
134 !memcmp(lline->line, line, len)) {
135 lline->parent_map |= this_mask;
142 lline = xmalloc(sizeof(*lline) + len + 1);
145 lline->parent_map = this_mask;
146 memcpy(lline->line, line, len);
147 lline->line[len] = 0;
148 *sline->lost_tail = lline;
149 sline->lost_tail = &lline->next;
152 struct combine_diff_state {
153 struct xdiff_emit_state xm;
161 struct sline *lost_bucket;
164 static void consume_line(void *state_, char *line, unsigned long len)
166 struct combine_diff_state *state = state_;
167 if (5 < len && !memcmp("@@ -", line, 4)) {
168 if (parse_hunk_header(line, len,
169 &state->ob, &state->on,
170 &state->nb, &state->nn))
172 state->lno = state->nb;
174 /* @@ -1,2 +0,0 @@ to remove the
179 /* @@ -X,Y +N,0 @@ removed Y lines
180 * that would have come *after* line N
181 * in the result. Our lost buckets hang
182 * to the line after the removed lines,
184 state->lost_bucket = &state->sline[state->nb];
186 state->lost_bucket = &state->sline[state->nb-1];
187 if (!state->sline[state->nb-1].p_lno)
188 state->sline[state->nb-1].p_lno =
189 xcalloc(state->num_parent,
190 sizeof(unsigned long));
191 state->sline[state->nb-1].p_lno[state->n] = state->ob;
194 if (!state->lost_bucket)
195 return; /* not in any hunk yet */
198 append_lost(state->lost_bucket, state->n, line+1, len-1);
201 state->sline[state->lno-1].flag |= state->nmask;
207 static void combine_diff(const unsigned char *parent, mmfile_t *result_file,
208 struct sline *sline, unsigned int cnt, int n,
211 unsigned int p_lno, lno;
212 unsigned long nmask = (1UL << n);
215 mmfile_t parent_file;
217 struct combine_diff_state state;
221 return; /* result deleted */
223 parent_file.ptr = grab_blob(parent, &sz);
224 parent_file.size = sz;
225 xpp.flags = XDF_NEED_MINIMAL;
228 ecb.outf = xdiff_outf;
230 memset(&state, 0, sizeof(state));
231 state.xm.consume = consume_line;
235 state.num_parent = num_parent;
238 xdl_diff(&parent_file, result_file, &xpp, &xecfg, &ecb);
239 free(parent_file.ptr);
241 /* Assign line numbers for this parent.
243 * sline[lno].p_lno[n] records the first line number
244 * (counting from 1) for parent N if the final hunk display
245 * started by showing sline[lno] (possibly showing the lost
246 * lines attached to it first).
248 for (lno = 0, p_lno = 1; lno <= cnt; lno++) {
250 sline[lno].p_lno[n] = p_lno;
252 /* How many lines would this sline advance the p_lno? */
253 ll = sline[lno].lost_head;
255 if (ll->parent_map & nmask)
256 p_lno++; /* '-' means parent had it */
259 if (lno < cnt && !(sline[lno].flag & nmask))
260 p_lno++; /* no '+' means parent had it */
262 sline[lno].p_lno[n] = p_lno; /* trailer */
265 static unsigned long context = 3;
266 static char combine_marker = '@';
268 static int interesting(struct sline *sline, unsigned long all_mask)
270 /* If some parents lost lines here, or if we have added to
271 * some parent, it is interesting.
273 return ((sline->flag & all_mask) || sline->lost_head);
276 static unsigned long adjust_hunk_tail(struct sline *sline,
277 unsigned long all_mask,
278 unsigned long hunk_begin,
281 /* i points at the first uninteresting line. If the last line
282 * of the hunk was interesting only because it has some
283 * deletion, then it is not all that interesting for the
284 * purpose of giving trailing context lines. This is because
285 * we output '-' line and then unmodified sline[i-1] itself in
286 * that case which gives us one extra context line.
288 if ((hunk_begin + 1 <= i) && !(sline[i-1].flag & all_mask))
293 static unsigned long find_next(struct sline *sline,
297 int look_for_uninteresting)
299 /* We have examined up to i-1 and are about to look at i.
300 * Find next interesting or uninteresting line. Here,
301 * "interesting" does not mean interesting(), but marked by
302 * the give_context() function below (i.e. it includes context
303 * lines that are not interesting to interesting() function
304 * that are surrounded by interesting() ones.
307 if (look_for_uninteresting
308 ? !(sline[i].flag & mark)
309 : (sline[i].flag & mark))
316 static int give_context(struct sline *sline, unsigned long cnt, int num_parent)
318 unsigned long all_mask = (1UL<<num_parent) - 1;
319 unsigned long mark = (1UL<<num_parent);
322 /* Two groups of interesting lines may have a short gap of
323 * uninteresting lines. Connect such groups to give them a
326 * We first start from what the interesting() function says,
327 * and mark them with "mark", and paint context lines with the
328 * mark. So interesting() would still say false for such context
329 * lines but they are treated as "interesting" in the end.
331 i = find_next(sline, mark, 0, cnt, 0);
336 unsigned long j = (context < i) ? (i - context) : 0;
339 /* Paint a few lines before the first interesting line. */
341 sline[j++].flag |= mark;
344 /* we know up to i is to be included. where does the
345 * next uninteresting one start?
347 j = find_next(sline, mark, i, cnt, 1);
349 break; /* the rest are all interesting */
351 /* lookahead context lines */
352 k = find_next(sline, mark, j, cnt, 0);
353 j = adjust_hunk_tail(sline, all_mask, i, j);
355 if (k < j + context) {
356 /* k is interesting and [j,k) are not, but
357 * paint them interesting because the gap is small.
360 sline[j++].flag |= mark;
365 /* j is the first uninteresting line and there is
366 * no overlap beyond it within context lines. Paint
367 * the trailing edge a bit.
370 k = (j + context < cnt+1) ? j + context : cnt+1;
372 sline[j++].flag |= mark;
377 static int make_hunks(struct sline *sline, unsigned long cnt,
378 int num_parent, int dense)
380 unsigned long all_mask = (1UL<<num_parent) - 1;
381 unsigned long mark = (1UL<<num_parent);
383 int has_interesting = 0;
385 for (i = 0; i <= cnt; i++) {
386 if (interesting(&sline[i], all_mask))
387 sline[i].flag |= mark;
389 sline[i].flag &= ~mark;
392 return give_context(sline, cnt, num_parent);
394 /* Look at each hunk, and if we have changes from only one
395 * parent, or the changes are the same from all but one
396 * parent, mark that uninteresting.
400 unsigned long j, hunk_begin, hunk_end;
401 unsigned long same_diff;
402 while (i <= cnt && !(sline[i].flag & mark))
405 break; /* No more interesting hunks */
407 for (j = i + 1; j <= cnt; j++) {
408 if (!(sline[j].flag & mark)) {
409 /* Look beyond the end to see if there
410 * is an interesting line after this
411 * hunk within context span.
413 unsigned long la; /* lookahead */
415 la = adjust_hunk_tail(sline, all_mask,
417 la = (la + context < cnt + 1) ?
418 (la + context) : cnt + 1;
420 if (sline[la].flag & mark) {
432 /* [i..hunk_end) are interesting. Now is it really
433 * interesting? We check if there are only two versions
434 * and the result matches one of them. That is, we look
436 * (+) line, which records lines added to which parents;
437 * this line appears in the result.
438 * (-) line, which records from what parents the line
439 * was removed; this line does not appear in the result.
440 * then check the set of parents the result has difference
441 * from, from all lines. If there are lines that has
442 * different set of parents that the result has differences
443 * from, that means we have more than two versions.
445 * Even when we have only two versions, if the result does
446 * not match any of the parents, the it should be considered
447 * interesting. In such a case, we would have all '+' line.
448 * After passing the above "two versions" test, that would
449 * appear as "the same set of parents" to be "all parents".
453 for (j = i; j < hunk_end && !has_interesting; j++) {
454 unsigned long this_diff = sline[j].flag & all_mask;
455 struct lline *ll = sline[j].lost_head;
457 /* This has some changes. Is it the
461 same_diff = this_diff;
462 else if (same_diff != this_diff) {
467 while (ll && !has_interesting) {
468 /* Lost this line from these parents;
469 * who are they? Are they the same?
471 this_diff = ll->parent_map;
473 same_diff = this_diff;
474 else if (same_diff != this_diff) {
481 if (!has_interesting && same_diff != all_mask) {
482 /* This hunk is not that interesting after all */
483 for (j = hunk_begin; j < hunk_end; j++)
484 sline[j].flag &= ~mark;
489 has_interesting = give_context(sline, cnt, num_parent);
490 return has_interesting;
493 static void show_parent_lno(struct sline *sline, unsigned long l0, unsigned long l1, int n)
495 l0 = sline[l0].p_lno[n];
496 l1 = sline[l1].p_lno[n];
497 printf(" -%lu,%lu", l0, l1-l0);
500 static void dump_sline(struct sline *sline, unsigned long cnt, int num_parent,
503 unsigned long mark = (1UL<<num_parent);
505 unsigned long lno = 0;
506 const char *c_frag = diff_get_color(use_color, DIFF_FRAGINFO);
507 const char *c_new = diff_get_color(use_color, DIFF_FILE_NEW);
508 const char *c_old = diff_get_color(use_color, DIFF_FILE_OLD);
509 const char *c_plain = diff_get_color(use_color, DIFF_PLAIN);
510 const char *c_reset = diff_get_color(use_color, DIFF_RESET);
513 return; /* result deleted */
516 struct sline *sl = &sline[lno];
517 unsigned long hunk_end;
518 unsigned long rlines;
519 while (lno <= cnt && !(sline[lno].flag & mark))
524 for (hunk_end = lno + 1; hunk_end <= cnt; hunk_end++)
525 if (!(sline[hunk_end].flag & mark))
528 rlines = hunk_end - lno;
530 rlines--; /* pointing at the last delete hunk */
531 fputs(c_frag, stdout);
532 for (i = 0; i <= num_parent; i++) putchar(combine_marker);
533 for (i = 0; i < num_parent; i++)
534 show_parent_lno(sline, lno, hunk_end, i);
535 printf(" +%lu,%lu ", lno+1, rlines);
536 for (i = 0; i <= num_parent; i++) putchar(combine_marker);
537 printf("%s\n", c_reset);
538 while (lno < hunk_end) {
541 unsigned long p_mask;
545 fputs(c_old, stdout);
546 for (j = 0; j < num_parent; j++) {
547 if (ll->parent_map & (1UL<<j))
552 printf("%s%s\n", ll->line, c_reset);
558 if (!(sl->flag & (mark-1)))
559 fputs(c_plain, stdout);
561 fputs(c_new, stdout);
562 for (j = 0; j < num_parent; j++) {
563 if (p_mask & sl->flag)
569 printf("%.*s%s\n", sl->len, sl->bol, c_reset);
574 static void reuse_combine_diff(struct sline *sline, unsigned long cnt,
577 /* We have already examined parent j and we know parent i
578 * and parent j are the same, so reuse the combined result
579 * of parent j for parent i.
581 unsigned long lno, imask, jmask;
585 for (lno = 0; lno <= cnt; lno++) {
586 struct lline *ll = sline->lost_head;
587 sline->p_lno[i] = sline->p_lno[j];
589 if (ll->parent_map & jmask)
590 ll->parent_map |= imask;
593 if (sline->flag & jmask)
594 sline->flag |= imask;
597 /* the overall size of the file (sline[cnt]) */
598 sline->p_lno[i] = sline->p_lno[j];
601 static void dump_quoted_path(const char *prefix, const char *path,
602 const char *c_meta, const char *c_reset)
604 printf("%s%s", c_meta, prefix);
605 if (quote_c_style(path, NULL, NULL, 0))
606 quote_c_style(path, NULL, stdout, 0);
609 printf("%s\n", c_reset);
612 static int show_patch_diff(struct combine_diff_path *elem, int num_parent,
613 int dense, struct rev_info *rev)
615 struct diff_options *opt = &rev->diffopt;
616 unsigned long result_size, cnt, lno;
618 struct sline *sline; /* survived lines */
619 int mode_differs = 0;
620 int i, show_hunks, shown_header = 0;
621 int working_tree_file = !memcmp(elem->sha1, null_sha1, 20);
622 int abbrev = opt->full_index ? 40 : DEFAULT_ABBREV;
623 mmfile_t result_file;
625 context = opt->context;
626 /* Read the result of merge first */
627 if (!working_tree_file)
628 result = grab_blob(elem->sha1, &result_size);
630 /* Used by diff-tree to read from the working tree */
633 if (0 <= (fd = open(elem->path, O_RDONLY)) &&
635 int len = st.st_size;
638 elem->mode = canon_mode(st.st_mode);
640 result = xmalloc(len + 1);
642 int done = xread(fd, result+sz, len-sz);
646 die("read error '%s'", elem->path);
655 result = xcalloc(1, 1);
661 for (cnt = 0, cp = result; cp < result + result_size; cp++) {
665 if (result_size && result[result_size-1] != '\n')
666 cnt++; /* incomplete line */
668 sline = xcalloc(cnt+2, sizeof(*sline));
669 sline[0].bol = result;
670 for (lno = 0; lno <= cnt + 1; lno++) {
671 sline[lno].lost_tail = &sline[lno].lost_head;
674 for (lno = 0, cp = result; cp < result + result_size; cp++) {
676 sline[lno].len = cp - sline[lno].bol;
679 sline[lno].bol = cp + 1;
682 if (result_size && result[result_size-1] != '\n')
683 sline[cnt-1].len = result_size - (sline[cnt-1].bol - result);
685 result_file.ptr = result;
686 result_file.size = result_size;
688 /* Even p_lno[cnt+1] is valid -- that is for the end line number
689 * for deletion hunk at the end.
691 sline[0].p_lno = xcalloc((cnt+2) * num_parent, sizeof(unsigned long));
692 for (lno = 0; lno <= cnt; lno++)
693 sline[lno+1].p_lno = sline[lno].p_lno + num_parent;
695 for (i = 0; i < num_parent; i++) {
697 for (j = 0; j < i; j++) {
698 if (!memcmp(elem->parent[i].sha1,
699 elem->parent[j].sha1, 20)) {
700 reuse_combine_diff(sline, cnt, i, j);
705 combine_diff(elem->parent[i].sha1, &result_file, sline,
707 if (elem->parent[i].mode != elem->mode)
711 show_hunks = make_hunks(sline, cnt, num_parent, dense);
713 if (show_hunks || mode_differs || working_tree_file) {
715 int use_color = opt->color_diff;
716 const char *c_meta = diff_get_color(use_color, DIFF_METAINFO);
717 const char *c_reset = diff_get_color(use_color, DIFF_RESET);
720 show_log(rev, opt->msg_sep);
721 dump_quoted_path(dense ? "diff --cc " : "diff --combined ",
722 elem->path, c_meta, c_reset);
723 printf("%sindex ", c_meta);
724 for (i = 0; i < num_parent; i++) {
725 abb = find_unique_abbrev(elem->parent[i].sha1,
727 printf("%s%s", i ? "," : "", abb);
729 abb = find_unique_abbrev(elem->sha1, abbrev);
730 printf("..%s%s\n", abb, c_reset);
733 int added = !!elem->mode;
734 for (i = 0; added && i < num_parent; i++)
735 if (elem->parent[i].status !=
739 printf("%snew file mode %06o",
743 printf("%sdeleted file ", c_meta);
745 for (i = 0; i < num_parent; i++) {
746 printf("%s%06o", i ? "," : "",
747 elem->parent[i].mode);
750 printf("..%06o", elem->mode);
752 printf("%s\n", c_reset);
754 dump_quoted_path("--- a/", elem->path, c_meta, c_reset);
755 dump_quoted_path("+++ b/", elem->path, c_meta, c_reset);
756 dump_sline(sline, cnt, num_parent, opt->color_diff);
760 for (lno = 0; lno < cnt; lno++) {
761 if (sline[lno].lost_head) {
762 struct lline *ll = sline[lno].lost_head;
764 struct lline *tmp = ll;
770 free(sline[0].p_lno);
775 #define COLONS "::::::::::::::::::::::::::::::::"
777 static void show_raw_diff(struct combine_diff_path *p, int num_parent, struct rev_info *rev)
779 struct diff_options *opt = &rev->diffopt;
782 int line_termination, inter_name_termination;
784 line_termination = opt->line_termination;
785 inter_name_termination = '\t';
786 if (!line_termination)
787 inter_name_termination = 0;
790 show_log(rev, opt->msg_sep);
792 if (opt->output_format & DIFF_FORMAT_RAW) {
793 offset = strlen(COLONS) - num_parent;
796 prefix = COLONS + offset;
799 for (i = 0; i < num_parent; i++) {
800 printf("%s%06o", prefix, p->parent[i].mode);
803 printf("%s%06o", prefix, p->mode);
806 for (i = 0; i < num_parent; i++)
807 printf(" %s", diff_unique_abbrev(p->parent[i].sha1,
809 printf(" %s ", diff_unique_abbrev(p->sha1, opt->abbrev));
812 if (opt->output_format & (DIFF_FORMAT_RAW | DIFF_FORMAT_NAME_STATUS)) {
813 for (i = 0; i < num_parent; i++)
814 putchar(p->parent[i].status);
815 putchar(inter_name_termination);
818 if (line_termination) {
819 if (quote_c_style(p->path, NULL, NULL, 0))
820 quote_c_style(p->path, NULL, stdout, 0);
822 printf("%s", p->path);
823 putchar(line_termination);
826 printf("%s%c", p->path, line_termination);
830 void show_combined_diff(struct combine_diff_path *p,
833 struct rev_info *rev)
835 struct diff_options *opt = &rev->diffopt;
838 if (opt->output_format & (DIFF_FORMAT_RAW |
840 DIFF_FORMAT_NAME_STATUS)) {
841 show_raw_diff(p, num_parent, rev);
842 } else if (opt->output_format & DIFF_FORMAT_PATCH) {
843 show_patch_diff(p, num_parent, dense, rev);
847 void diff_tree_combined(const unsigned char *sha1,
848 const unsigned char parent[][20],
851 struct rev_info *rev)
853 struct diff_options *opt = &rev->diffopt;
854 struct diff_options diffopts;
855 struct combine_diff_path *p, *paths = NULL;
856 int i, num_paths, needsep, show_log_first;
859 diffopts.output_format = DIFF_FORMAT_NO_OUTPUT;
860 diffopts.recursive = 1;
862 show_log_first = !!rev->loginfo;
864 /* find set of paths that everybody touches */
865 for (i = 0; i < num_parent; i++) {
866 /* show stat against the first parent even
867 * when doing combined diff.
869 if (i == 0 && opt->output_format & DIFF_FORMAT_DIFFSTAT)
870 diffopts.output_format = DIFF_FORMAT_DIFFSTAT;
872 diffopts.output_format = DIFF_FORMAT_NO_OUTPUT;
873 diff_tree_sha1(parent[i], sha1, "", &diffopts);
874 diffcore_std(&diffopts);
875 paths = intersect_paths(paths, i, num_parent);
877 if (show_log_first && i == 0) {
878 show_log(rev, opt->msg_sep);
879 if (rev->verbose_header && opt->output_format)
880 putchar(opt->line_termination);
882 diff_flush(&diffopts);
885 /* find out surviving paths */
886 for (num_paths = 0, p = paths; p; p = p->next) {
891 if (opt->output_format & (DIFF_FORMAT_RAW |
893 DIFF_FORMAT_NAME_STATUS)) {
894 for (p = paths; p; p = p->next) {
896 show_raw_diff(p, num_parent, rev);
900 else if (opt->output_format & DIFF_FORMAT_DIFFSTAT)
902 if (opt->output_format & DIFF_FORMAT_PATCH) {
904 putchar(opt->line_termination);
905 for (p = paths; p; p = p->next) {
907 show_patch_diff(p, num_parent, dense,
913 /* Clean things up */
915 struct combine_diff_path *tmp = paths;
921 void diff_tree_combined_merge(const unsigned char *sha1,
922 int dense, struct rev_info *rev)
925 const unsigned char (*parent)[20];
926 struct commit *commit = lookup_commit(sha1);
927 struct commit_list *parents;
930 for (parents = commit->parents, num_parent = 0;
932 parents = parents->next, num_parent++)
935 parent = xmalloc(num_parent * sizeof(*parent));
936 for (parents = commit->parents, num_parent = 0;
938 parents = parents->next, num_parent++)
939 memcpy(parent + num_parent, parents->item->object.sha1, 20);
940 diff_tree_combined(sha1, parent, num_parent, dense, rev);