Small typofix in mailsplit.c
[git/dscho.git] / diff.c
blob3e52fec18792056e230420bdeabff0f9dab5b35a
1 /*
2 * Copyright (C) 2005 Junio C Hamano
3 */
4 #include <sys/types.h>
5 #include <sys/wait.h>
6 #include <signal.h>
7 #include "cache.h"
8 #include "quote.h"
9 #include "diff.h"
10 #include "diffcore.h"
12 static const char *diff_opts = "-pu";
13 static unsigned char null_sha1[20] = { 0, };
15 static int reverse_diff;
16 static int use_size_cache;
18 static const char *external_diff(void)
20 static const char *external_diff_cmd = NULL;
21 static int done_preparing = 0;
23 if (done_preparing)
24 return external_diff_cmd;
27 * Default values above are meant to match the
28 * Linux kernel development style. Examples of
29 * alternative styles you can specify via environment
30 * variables are:
32 * GIT_DIFF_OPTS="-c";
34 if (gitenv("GIT_EXTERNAL_DIFF"))
35 external_diff_cmd = gitenv("GIT_EXTERNAL_DIFF");
37 /* In case external diff fails... */
38 diff_opts = gitenv("GIT_DIFF_OPTS") ? : diff_opts;
40 done_preparing = 1;
41 return external_diff_cmd;
44 #define TEMPFILE_PATH_LEN 50
46 static struct diff_tempfile {
47 const char *name; /* filename external diff should read from */
48 char hex[41];
49 char mode[10];
50 char tmp_path[TEMPFILE_PATH_LEN];
51 } diff_temp[2];
53 static int count_lines(const char *filename)
55 FILE *in;
56 int count, ch, completely_empty = 1, nl_just_seen = 0;
57 in = fopen(filename, "r");
58 count = 0;
59 while ((ch = fgetc(in)) != EOF)
60 if (ch == '\n') {
61 count++;
62 nl_just_seen = 1;
63 completely_empty = 0;
65 else {
66 nl_just_seen = 0;
67 completely_empty = 0;
69 fclose(in);
70 if (completely_empty)
71 return 0;
72 if (!nl_just_seen)
73 count++; /* no trailing newline */
74 return count;
77 static void print_line_count(int count)
79 switch (count) {
80 case 0:
81 printf("0,0");
82 break;
83 case 1:
84 printf("1");
85 break;
86 default:
87 printf("1,%d", count);
88 break;
92 static void copy_file(int prefix, const char *filename)
94 FILE *in;
95 int ch, nl_just_seen = 1;
96 in = fopen(filename, "r");
97 while ((ch = fgetc(in)) != EOF) {
98 if (nl_just_seen)
99 putchar(prefix);
100 putchar(ch);
101 if (ch == '\n')
102 nl_just_seen = 1;
103 else
104 nl_just_seen = 0;
106 fclose(in);
107 if (!nl_just_seen)
108 printf("\n\\ No newline at end of file\n");
111 static void emit_rewrite_diff(const char *name_a,
112 const char *name_b,
113 struct diff_tempfile *temp)
115 /* Use temp[i].name as input, name_a and name_b as labels */
116 int lc_a, lc_b;
117 lc_a = count_lines(temp[0].name);
118 lc_b = count_lines(temp[1].name);
119 printf("--- %s\n+++ %s\n@@ -", name_a, name_b);
120 print_line_count(lc_a);
121 printf(" +");
122 print_line_count(lc_b);
123 printf(" @@\n");
124 if (lc_a)
125 copy_file('-', temp[0].name);
126 if (lc_b)
127 copy_file('+', temp[1].name);
130 static void builtin_diff(const char *name_a,
131 const char *name_b,
132 struct diff_tempfile *temp,
133 const char *xfrm_msg,
134 int complete_rewrite)
136 int i, next_at, cmd_size;
137 const char *const diff_cmd = "diff -L%s%s -L%s%s";
138 const char *const diff_arg = "%s %s||:"; /* "||:" is to return 0 */
139 const char *input_name_sq[2];
140 const char *path0[2];
141 const char *path1[2];
142 const char *name_sq[2];
143 char *cmd;
145 name_sq[0] = sq_quote(name_a);
146 name_sq[1] = sq_quote(name_b);
148 /* diff_cmd and diff_arg have 6 %s in total which makes
149 * the sum of these strings 12 bytes larger than required.
150 * we use 2 spaces around diff-opts, and we need to count
151 * terminating NUL, so we subtract 9 here.
153 cmd_size = (strlen(diff_cmd) + strlen(diff_opts) +
154 strlen(diff_arg) - 9);
155 for (i = 0; i < 2; i++) {
156 input_name_sq[i] = sq_quote(temp[i].name);
157 if (!strcmp(temp[i].name, "/dev/null")) {
158 path0[i] = "/dev/null";
159 path1[i] = "";
160 } else {
161 path0[i] = i ? "b/" : "a/";
162 path1[i] = name_sq[i];
164 cmd_size += (strlen(path0[i]) + strlen(path1[i]) +
165 strlen(input_name_sq[i]));
168 cmd = xmalloc(cmd_size);
170 next_at = 0;
171 next_at += snprintf(cmd+next_at, cmd_size-next_at,
172 diff_cmd,
173 path0[0], path1[0], path0[1], path1[1]);
174 next_at += snprintf(cmd+next_at, cmd_size-next_at,
175 " %s ", diff_opts);
176 next_at += snprintf(cmd+next_at, cmd_size-next_at,
177 diff_arg, input_name_sq[0], input_name_sq[1]);
179 printf("diff --git a/%s b/%s\n", name_a, name_b);
180 if (!path1[0][0]) {
181 printf("new file mode %s\n", temp[1].mode);
182 if (xfrm_msg && xfrm_msg[0])
183 puts(xfrm_msg);
185 else if (!path1[1][0]) {
186 printf("deleted file mode %s\n", temp[0].mode);
187 if (xfrm_msg && xfrm_msg[0])
188 puts(xfrm_msg);
190 else {
191 if (strcmp(temp[0].mode, temp[1].mode)) {
192 printf("old mode %s\n", temp[0].mode);
193 printf("new mode %s\n", temp[1].mode);
195 if (xfrm_msg && xfrm_msg[0])
196 puts(xfrm_msg);
197 if (strncmp(temp[0].mode, temp[1].mode, 3))
198 /* we do not run diff between different kind
199 * of objects.
201 exit(0);
202 if (complete_rewrite) {
203 fflush(NULL);
204 emit_rewrite_diff(name_a, name_b, temp);
205 exit(0);
208 fflush(NULL);
209 execlp("/bin/sh","sh", "-c", cmd, NULL);
212 struct diff_filespec *alloc_filespec(const char *path)
214 int namelen = strlen(path);
215 struct diff_filespec *spec = xmalloc(sizeof(*spec) + namelen + 1);
216 spec->path = (char *)(spec + 1);
217 strcpy(spec->path, path);
218 spec->should_free = spec->should_munmap = 0;
219 spec->xfrm_flags = 0;
220 spec->size = 0;
221 spec->data = NULL;
222 spec->mode = 0;
223 memset(spec->sha1, 0, 20);
224 return spec;
227 void fill_filespec(struct diff_filespec *spec, const unsigned char *sha1,
228 unsigned short mode)
230 if (mode) {
231 spec->mode = DIFF_FILE_CANON_MODE(mode);
232 memcpy(spec->sha1, sha1, 20);
233 spec->sha1_valid = !!memcmp(sha1, null_sha1, 20);
238 * Given a name and sha1 pair, if the dircache tells us the file in
239 * the work tree has that object contents, return true, so that
240 * prepare_temp_file() does not have to inflate and extract.
242 static int work_tree_matches(const char *name, const unsigned char *sha1)
244 struct cache_entry *ce;
245 struct stat st;
246 int pos, len;
248 /* We do not read the cache ourselves here, because the
249 * benchmark with my previous version that always reads cache
250 * shows that it makes things worse for diff-tree comparing
251 * two linux-2.6 kernel trees in an already checked out work
252 * tree. This is because most diff-tree comparisons deal with
253 * only a small number of files, while reading the cache is
254 * expensive for a large project, and its cost outweighs the
255 * savings we get by not inflating the object to a temporary
256 * file. Practically, this code only helps when we are used
257 * by diff-cache --cached, which does read the cache before
258 * calling us.
260 if (!active_cache)
261 return 0;
263 len = strlen(name);
264 pos = cache_name_pos(name, len);
265 if (pos < 0)
266 return 0;
267 ce = active_cache[pos];
268 if ((lstat(name, &st) < 0) ||
269 !S_ISREG(st.st_mode) || /* careful! */
270 ce_match_stat(ce, &st) ||
271 memcmp(sha1, ce->sha1, 20))
272 return 0;
273 /* we return 1 only when we can stat, it is a regular file,
274 * stat information matches, and sha1 recorded in the cache
275 * matches. I.e. we know the file in the work tree really is
276 * the same as the <name, sha1> pair.
278 return 1;
281 static struct sha1_size_cache {
282 unsigned char sha1[20];
283 unsigned long size;
284 } **sha1_size_cache;
285 static int sha1_size_cache_nr, sha1_size_cache_alloc;
287 static struct sha1_size_cache *locate_size_cache(unsigned char *sha1,
288 int find_only,
289 unsigned long size)
291 int first, last;
292 struct sha1_size_cache *e;
294 first = 0;
295 last = sha1_size_cache_nr;
296 while (last > first) {
297 int cmp, next = (last + first) >> 1;
298 e = sha1_size_cache[next];
299 cmp = memcmp(e->sha1, sha1, 20);
300 if (!cmp)
301 return e;
302 if (cmp < 0) {
303 last = next;
304 continue;
306 first = next+1;
308 /* not found */
309 if (find_only)
310 return NULL;
311 /* insert to make it at "first" */
312 if (sha1_size_cache_alloc <= sha1_size_cache_nr) {
313 sha1_size_cache_alloc = alloc_nr(sha1_size_cache_alloc);
314 sha1_size_cache = xrealloc(sha1_size_cache,
315 sha1_size_cache_alloc *
316 sizeof(*sha1_size_cache));
318 sha1_size_cache_nr++;
319 if (first < sha1_size_cache_nr)
320 memmove(sha1_size_cache + first + 1, sha1_size_cache + first,
321 (sha1_size_cache_nr - first - 1) *
322 sizeof(*sha1_size_cache));
323 e = xmalloc(sizeof(struct sha1_size_cache));
324 sha1_size_cache[first] = e;
325 memcpy(e->sha1, sha1, 20);
326 e->size = size;
327 return e;
331 * While doing rename detection and pickaxe operation, we may need to
332 * grab the data for the blob (or file) for our own in-core comparison.
333 * diff_filespec has data and size fields for this purpose.
335 int diff_populate_filespec(struct diff_filespec *s, int size_only)
337 int err = 0;
338 if (!DIFF_FILE_VALID(s))
339 die("internal error: asking to populate invalid file.");
340 if (S_ISDIR(s->mode))
341 return -1;
343 if (!use_size_cache)
344 size_only = 0;
346 if (s->data)
347 return err;
348 if (!s->sha1_valid ||
349 work_tree_matches(s->path, s->sha1)) {
350 struct stat st;
351 int fd;
352 if (lstat(s->path, &st) < 0) {
353 if (errno == ENOENT) {
354 err_empty:
355 err = -1;
356 empty:
357 s->data = "";
358 s->size = 0;
359 return err;
362 s->size = st.st_size;
363 if (!s->size)
364 goto empty;
365 if (size_only)
366 return 0;
367 if (S_ISLNK(st.st_mode)) {
368 int ret;
369 s->data = xmalloc(s->size);
370 s->should_free = 1;
371 ret = readlink(s->path, s->data, s->size);
372 if (ret < 0) {
373 free(s->data);
374 goto err_empty;
376 return 0;
378 fd = open(s->path, O_RDONLY);
379 if (fd < 0)
380 goto err_empty;
381 s->data = mmap(NULL, s->size, PROT_READ, MAP_PRIVATE, fd, 0);
382 close(fd);
383 if (s->data == MAP_FAILED)
384 goto err_empty;
385 s->should_munmap = 1;
387 else {
388 char type[20];
389 struct sha1_size_cache *e;
391 if (size_only) {
392 e = locate_size_cache(s->sha1, 1, 0);
393 if (e) {
394 s->size = e->size;
395 return 0;
397 if (!sha1_object_info(s->sha1, type, &s->size))
398 locate_size_cache(s->sha1, 0, s->size);
400 else {
401 s->data = read_sha1_file(s->sha1, type, &s->size);
402 s->should_free = 1;
405 return 0;
408 void diff_free_filespec_data(struct diff_filespec *s)
410 if (s->should_free)
411 free(s->data);
412 else if (s->should_munmap)
413 munmap(s->data, s->size);
414 s->should_free = s->should_munmap = 0;
415 s->data = NULL;
418 static void prep_temp_blob(struct diff_tempfile *temp,
419 void *blob,
420 unsigned long size,
421 unsigned char *sha1,
422 int mode)
424 int fd;
426 fd = git_mkstemp(temp->tmp_path, TEMPFILE_PATH_LEN, ".diff_XXXXXX");
427 if (fd < 0)
428 die("unable to create temp-file");
429 if (write(fd, blob, size) != size)
430 die("unable to write temp-file");
431 close(fd);
432 temp->name = temp->tmp_path;
433 strcpy(temp->hex, sha1_to_hex(sha1));
434 temp->hex[40] = 0;
435 sprintf(temp->mode, "%06o", mode);
438 static void prepare_temp_file(const char *name,
439 struct diff_tempfile *temp,
440 struct diff_filespec *one)
442 if (!DIFF_FILE_VALID(one)) {
443 not_a_valid_file:
444 /* A '-' entry produces this for file-2, and
445 * a '+' entry produces this for file-1.
447 temp->name = "/dev/null";
448 strcpy(temp->hex, ".");
449 strcpy(temp->mode, ".");
450 return;
453 if (!one->sha1_valid ||
454 work_tree_matches(name, one->sha1)) {
455 struct stat st;
456 if (lstat(name, &st) < 0) {
457 if (errno == ENOENT)
458 goto not_a_valid_file;
459 die("stat(%s): %s", name, strerror(errno));
461 if (S_ISLNK(st.st_mode)) {
462 int ret;
463 char *buf, buf_[1024];
464 buf = ((sizeof(buf_) < st.st_size) ?
465 xmalloc(st.st_size) : buf_);
466 ret = readlink(name, buf, st.st_size);
467 if (ret < 0)
468 die("readlink(%s)", name);
469 prep_temp_blob(temp, buf, st.st_size,
470 (one->sha1_valid ?
471 one->sha1 : null_sha1),
472 (one->sha1_valid ?
473 one->mode : S_IFLNK));
475 else {
476 /* we can borrow from the file in the work tree */
477 temp->name = name;
478 if (!one->sha1_valid)
479 strcpy(temp->hex, sha1_to_hex(null_sha1));
480 else
481 strcpy(temp->hex, sha1_to_hex(one->sha1));
482 /* Even though we may sometimes borrow the
483 * contents from the work tree, we always want
484 * one->mode. mode is trustworthy even when
485 * !(one->sha1_valid), as long as
486 * DIFF_FILE_VALID(one).
488 sprintf(temp->mode, "%06o", one->mode);
490 return;
492 else {
493 if (diff_populate_filespec(one, 0))
494 die("cannot read data blob for %s", one->path);
495 prep_temp_blob(temp, one->data, one->size,
496 one->sha1, one->mode);
500 static void remove_tempfile(void)
502 int i;
504 for (i = 0; i < 2; i++)
505 if (diff_temp[i].name == diff_temp[i].tmp_path) {
506 unlink(diff_temp[i].name);
507 diff_temp[i].name = NULL;
511 static void remove_tempfile_on_signal(int signo)
513 remove_tempfile();
516 /* An external diff command takes:
518 * diff-cmd name infile1 infile1-sha1 infile1-mode \
519 * infile2 infile2-sha1 infile2-mode [ rename-to ]
522 static void run_external_diff(const char *pgm,
523 const char *name,
524 const char *other,
525 struct diff_filespec *one,
526 struct diff_filespec *two,
527 const char *xfrm_msg,
528 int complete_rewrite)
530 struct diff_tempfile *temp = diff_temp;
531 pid_t pid;
532 int status;
533 static int atexit_asked = 0;
535 if (one && two) {
536 prepare_temp_file(name, &temp[0], one);
537 prepare_temp_file(other ? : name, &temp[1], two);
538 if (! atexit_asked &&
539 (temp[0].name == temp[0].tmp_path ||
540 temp[1].name == temp[1].tmp_path)) {
541 atexit_asked = 1;
542 atexit(remove_tempfile);
544 signal(SIGINT, remove_tempfile_on_signal);
547 fflush(NULL);
548 pid = fork();
549 if (pid < 0)
550 die("unable to fork");
551 if (!pid) {
552 if (pgm) {
553 if (one && two) {
554 const char *exec_arg[10];
555 const char **arg = &exec_arg[0];
556 *arg++ = pgm;
557 *arg++ = name;
558 *arg++ = temp[0].name;
559 *arg++ = temp[0].hex;
560 *arg++ = temp[0].mode;
561 *arg++ = temp[1].name;
562 *arg++ = temp[1].hex;
563 *arg++ = temp[1].mode;
564 if (other) {
565 *arg++ = other;
566 *arg++ = xfrm_msg;
568 *arg = NULL;
569 execvp(pgm, (char *const*) exec_arg);
571 else
572 execlp(pgm, pgm, name, NULL);
575 * otherwise we use the built-in one.
577 if (one && two)
578 builtin_diff(name, other ? : name, temp, xfrm_msg,
579 complete_rewrite);
580 else
581 printf("* Unmerged path %s\n", name);
582 exit(0);
584 if (waitpid(pid, &status, 0) < 0 ||
585 !WIFEXITED(status) || WEXITSTATUS(status)) {
586 /* Earlier we did not check the exit status because
587 * diff exits non-zero if files are different, and
588 * we are not interested in knowing that. It was a
589 * mistake which made it harder to quit a diff-*
590 * session that uses the git-apply-patch-script as
591 * the GIT_EXTERNAL_DIFF. A custom GIT_EXTERNAL_DIFF
592 * should also exit non-zero only when it wants to
593 * abort the entire diff-* session.
595 remove_tempfile();
596 fprintf(stderr, "external diff died, stopping at %s.\n", name);
597 exit(1);
599 remove_tempfile();
602 static void run_diff(struct diff_filepair *p)
604 const char *pgm = external_diff();
605 char msg_[PATH_MAX*2+200], *xfrm_msg;
606 struct diff_filespec *one;
607 struct diff_filespec *two;
608 const char *name;
609 const char *other;
610 int complete_rewrite = 0;
612 if (DIFF_PAIR_UNMERGED(p)) {
613 /* unmerged */
614 run_external_diff(pgm, p->one->path, NULL, NULL, NULL, NULL,
616 return;
619 name = p->one->path;
620 other = (strcmp(name, p->two->path) ? p->two->path : NULL);
621 one = p->one; two = p->two;
622 switch (p->status) {
623 case DIFF_STATUS_COPIED:
624 sprintf(msg_,
625 "similarity index %d%%\n"
626 "copy from %s\n"
627 "copy to %s",
628 (int)(0.5 + p->score * 100.0/MAX_SCORE),
629 name, other);
630 xfrm_msg = msg_;
631 break;
632 case DIFF_STATUS_RENAMED:
633 sprintf(msg_,
634 "similarity index %d%%\n"
635 "rename from %s\n"
636 "rename to %s",
637 (int)(0.5 + p->score * 100.0/MAX_SCORE),
638 name, other);
639 xfrm_msg = msg_;
640 break;
641 case DIFF_STATUS_MODIFIED:
642 if (p->score) {
643 sprintf(msg_,
644 "dissimilarity index %d%%",
645 (int)(0.5 + p->score * 100.0/MAX_SCORE));
646 xfrm_msg = msg_;
647 complete_rewrite = 1;
648 break;
650 /* fallthru */
651 default:
652 xfrm_msg = NULL;
655 if (!pgm &&
656 DIFF_FILE_VALID(one) && DIFF_FILE_VALID(two) &&
657 (S_IFMT & one->mode) != (S_IFMT & two->mode)) {
658 /* a filepair that changes between file and symlink
659 * needs to be split into deletion and creation.
661 struct diff_filespec *null = alloc_filespec(two->path);
662 run_external_diff(NULL, name, other, one, null, xfrm_msg, 0);
663 free(null);
664 null = alloc_filespec(one->path);
665 run_external_diff(NULL, name, other, null, two, xfrm_msg, 0);
666 free(null);
668 else
669 run_external_diff(pgm, name, other, one, two, xfrm_msg,
670 complete_rewrite);
673 void diff_setup(int flags)
675 if (flags & DIFF_SETUP_REVERSE)
676 reverse_diff = 1;
677 if (flags & DIFF_SETUP_USE_CACHE) {
678 if (!active_cache)
679 /* read-cache does not die even when it fails
680 * so it is safe for us to do this here. Also
681 * it does not smudge active_cache or active_nr
682 * when it fails, so we do not have to worry about
683 * cleaning it up oufselves either.
685 read_cache();
687 if (flags & DIFF_SETUP_USE_SIZE_CACHE)
688 use_size_cache = 1;
692 static int parse_num(const char **cp_p)
694 int num, scale, ch, cnt;
695 const char *cp = *cp_p;
697 cnt = num = 0;
698 scale = 1;
699 while ('0' <= (ch = *cp) && ch <= '9') {
700 if (cnt++ < 5) {
701 /* We simply ignore more than 5 digits precision. */
702 scale *= 10;
703 num = num * 10 + ch - '0';
705 *cp++;
707 *cp_p = cp;
709 /* user says num divided by scale and we say internally that
710 * is MAX_SCORE * num / scale.
712 return (MAX_SCORE * num / scale);
715 int diff_scoreopt_parse(const char *opt)
717 int opt1, opt2, cmd;
719 if (*opt++ != '-')
720 return -1;
721 cmd = *opt++;
722 if (cmd != 'M' && cmd != 'C' && cmd != 'B')
723 return -1; /* that is not a -M, -C nor -B option */
725 opt1 = parse_num(&opt);
726 if (cmd != 'B')
727 opt2 = 0;
728 else {
729 if (*opt == 0)
730 opt2 = 0;
731 else if (*opt != '/')
732 return -1; /* we expect -B80/99 or -B80 */
733 else {
734 opt++;
735 opt2 = parse_num(&opt);
738 if (*opt != 0)
739 return -1;
740 return opt1 | (opt2 << 16);
743 struct diff_queue_struct diff_queued_diff;
745 void diff_q(struct diff_queue_struct *queue, struct diff_filepair *dp)
747 if (queue->alloc <= queue->nr) {
748 queue->alloc = alloc_nr(queue->alloc);
749 queue->queue = xrealloc(queue->queue,
750 sizeof(dp) * queue->alloc);
752 queue->queue[queue->nr++] = dp;
755 struct diff_filepair *diff_queue(struct diff_queue_struct *queue,
756 struct diff_filespec *one,
757 struct diff_filespec *two)
759 struct diff_filepair *dp = xmalloc(sizeof(*dp));
760 dp->one = one;
761 dp->two = two;
762 dp->score = 0;
763 dp->status = 0;
764 dp->source_stays = 0;
765 dp->broken_pair = 0;
766 diff_q(queue, dp);
767 return dp;
770 void diff_free_filepair(struct diff_filepair *p)
772 diff_free_filespec_data(p->one);
773 diff_free_filespec_data(p->two);
774 free(p);
777 static void diff_flush_raw(struct diff_filepair *p,
778 int line_termination,
779 int inter_name_termination)
781 int two_paths;
782 char status[10];
784 if (line_termination) {
785 const char *const err =
786 "path %s cannot be expressed without -z";
787 if (strchr(p->one->path, line_termination) ||
788 strchr(p->one->path, inter_name_termination))
789 die(err, p->one->path);
790 if (strchr(p->two->path, line_termination) ||
791 strchr(p->two->path, inter_name_termination))
792 die(err, p->two->path);
795 if (p->score)
796 sprintf(status, "%c%03d", p->status,
797 (int)(0.5 + p->score * 100.0/MAX_SCORE));
798 else {
799 status[0] = p->status;
800 status[1] = 0;
802 switch (p->status) {
803 case DIFF_STATUS_COPIED:
804 case DIFF_STATUS_RENAMED:
805 two_paths = 1;
806 break;
807 case DIFF_STATUS_ADDED:
808 case DIFF_STATUS_DELETED:
809 two_paths = 0;
810 break;
811 default:
812 two_paths = 0;
813 break;
815 printf(":%06o %06o %s ",
816 p->one->mode, p->two->mode, sha1_to_hex(p->one->sha1));
817 printf("%s %s%c%s",
818 sha1_to_hex(p->two->sha1),
819 status,
820 inter_name_termination,
821 p->one->path);
822 if (two_paths)
823 printf("%c%s", inter_name_termination, p->two->path);
824 putchar(line_termination);
827 static void diff_flush_name(struct diff_filepair *p,
828 int line_termination)
830 printf("%s%c", p->two->path, line_termination);
833 int diff_unmodified_pair(struct diff_filepair *p)
835 /* This function is written stricter than necessary to support
836 * the currently implemented transformers, but the idea is to
837 * let transformers to produce diff_filepairs any way they want,
838 * and filter and clean them up here before producing the output.
840 struct diff_filespec *one, *two;
842 if (DIFF_PAIR_UNMERGED(p))
843 return 0; /* unmerged is interesting */
845 one = p->one;
846 two = p->two;
848 /* deletion, addition, mode or type change
849 * and rename are all interesting.
851 if (DIFF_FILE_VALID(one) != DIFF_FILE_VALID(two) ||
852 DIFF_PAIR_MODE_CHANGED(p) ||
853 strcmp(one->path, two->path))
854 return 0;
856 /* both are valid and point at the same path. that is, we are
857 * dealing with a change.
859 if (one->sha1_valid && two->sha1_valid &&
860 !memcmp(one->sha1, two->sha1, sizeof(one->sha1)))
861 return 1; /* no change */
862 if (!one->sha1_valid && !two->sha1_valid)
863 return 1; /* both look at the same file on the filesystem. */
864 return 0;
867 static void diff_flush_patch(struct diff_filepair *p)
869 if (diff_unmodified_pair(p))
870 return;
872 if ((DIFF_FILE_VALID(p->one) && S_ISDIR(p->one->mode)) ||
873 (DIFF_FILE_VALID(p->two) && S_ISDIR(p->two->mode)))
874 return; /* no tree diffs in patch format */
876 run_diff(p);
879 int diff_queue_is_empty(void)
881 struct diff_queue_struct *q = &diff_queued_diff;
882 int i;
883 for (i = 0; i < q->nr; i++)
884 if (!diff_unmodified_pair(q->queue[i]))
885 return 0;
886 return 1;
889 #if DIFF_DEBUG
890 void diff_debug_filespec(struct diff_filespec *s, int x, const char *one)
892 fprintf(stderr, "queue[%d] %s (%s) %s %06o %s\n",
893 x, one ? : "",
894 s->path,
895 DIFF_FILE_VALID(s) ? "valid" : "invalid",
896 s->mode,
897 s->sha1_valid ? sha1_to_hex(s->sha1) : "");
898 fprintf(stderr, "queue[%d] %s size %lu flags %d\n",
899 x, one ? : "",
900 s->size, s->xfrm_flags);
903 void diff_debug_filepair(const struct diff_filepair *p, int i)
905 diff_debug_filespec(p->one, i, "one");
906 diff_debug_filespec(p->two, i, "two");
907 fprintf(stderr, "score %d, status %c stays %d broken %d\n",
908 p->score, p->status ? : '?',
909 p->source_stays, p->broken_pair);
912 void diff_debug_queue(const char *msg, struct diff_queue_struct *q)
914 int i;
915 if (msg)
916 fprintf(stderr, "%s\n", msg);
917 fprintf(stderr, "q->nr = %d\n", q->nr);
918 for (i = 0; i < q->nr; i++) {
919 struct diff_filepair *p = q->queue[i];
920 diff_debug_filepair(p, i);
923 #endif
925 static void diff_resolve_rename_copy(void)
927 int i, j;
928 struct diff_filepair *p, *pp;
929 struct diff_queue_struct *q = &diff_queued_diff;
931 diff_debug_queue("resolve-rename-copy", q);
933 for (i = 0; i < q->nr; i++) {
934 p = q->queue[i];
935 p->status = 0; /* undecided */
936 if (DIFF_PAIR_UNMERGED(p))
937 p->status = DIFF_STATUS_UNMERGED;
938 else if (!DIFF_FILE_VALID(p->one))
939 p->status = DIFF_STATUS_ADDED;
940 else if (!DIFF_FILE_VALID(p->two))
941 p->status = DIFF_STATUS_DELETED;
942 else if (DIFF_PAIR_TYPE_CHANGED(p))
943 p->status = DIFF_STATUS_TYPE_CHANGED;
945 /* from this point on, we are dealing with a pair
946 * whose both sides are valid and of the same type, i.e.
947 * either in-place edit or rename/copy edit.
949 else if (DIFF_PAIR_RENAME(p)) {
950 if (p->source_stays) {
951 p->status = DIFF_STATUS_COPIED;
952 continue;
954 /* See if there is some other filepair that
955 * copies from the same source as us. If so
956 * we are a copy. Otherwise we are a rename.
958 for (j = i + 1; j < q->nr; j++) {
959 pp = q->queue[j];
960 if (strcmp(pp->one->path, p->one->path))
961 continue; /* not us */
962 if (!DIFF_PAIR_RENAME(pp))
963 continue; /* not a rename/copy */
964 /* pp is a rename/copy from the same source */
965 p->status = DIFF_STATUS_COPIED;
966 break;
968 if (!p->status)
969 p->status = DIFF_STATUS_RENAMED;
971 else if (memcmp(p->one->sha1, p->two->sha1, 20) ||
972 p->one->mode != p->two->mode)
973 p->status = DIFF_STATUS_MODIFIED;
974 else {
975 /* This is a "no-change" entry and should not
976 * happen anymore, but prepare for broken callers.
978 error("feeding unmodified %s to diffcore",
979 p->one->path);
980 p->status = DIFF_STATUS_UNKNOWN;
983 diff_debug_queue("resolve-rename-copy done", q);
986 void diff_flush(int diff_output_style, int line_termination)
988 struct diff_queue_struct *q = &diff_queued_diff;
989 int i;
990 int inter_name_termination = '\t';
992 if (!line_termination)
993 inter_name_termination = 0;
995 for (i = 0; i < q->nr; i++) {
996 struct diff_filepair *p = q->queue[i];
997 if ((diff_output_style == DIFF_FORMAT_NO_OUTPUT) ||
998 (p->status == DIFF_STATUS_UNKNOWN))
999 continue;
1000 if (p->status == 0)
1001 die("internal error in diff-resolve-rename-copy");
1002 switch (diff_output_style) {
1003 case DIFF_FORMAT_PATCH:
1004 diff_flush_patch(p);
1005 break;
1006 case DIFF_FORMAT_RAW:
1007 diff_flush_raw(p, line_termination,
1008 inter_name_termination);
1009 break;
1010 case DIFF_FORMAT_NAME:
1011 diff_flush_name(p, line_termination);
1012 break;
1015 for (i = 0; i < q->nr; i++)
1016 diff_free_filepair(q->queue[i]);
1017 free(q->queue);
1018 q->queue = NULL;
1019 q->nr = q->alloc = 0;
1022 static void diffcore_apply_filter(const char *filter)
1024 int i;
1025 struct diff_queue_struct *q = &diff_queued_diff;
1026 struct diff_queue_struct outq;
1027 outq.queue = NULL;
1028 outq.nr = outq.alloc = 0;
1030 if (!filter)
1031 return;
1033 if (strchr(filter, DIFF_STATUS_FILTER_AON)) {
1034 int found;
1035 for (i = found = 0; !found && i < q->nr; i++) {
1036 struct diff_filepair *p = q->queue[i];
1037 if (((p->status == DIFF_STATUS_MODIFIED) &&
1038 ((p->score &&
1039 strchr(filter, DIFF_STATUS_FILTER_BROKEN)) ||
1040 (!p->score &&
1041 strchr(filter, DIFF_STATUS_MODIFIED)))) ||
1042 ((p->status != DIFF_STATUS_MODIFIED) &&
1043 strchr(filter, p->status)))
1044 found++;
1046 if (found)
1047 return;
1049 /* otherwise we will clear the whole queue
1050 * by copying the empty outq at the end of this
1051 * function, but first clear the current entries
1052 * in the queue.
1054 for (i = 0; i < q->nr; i++)
1055 diff_free_filepair(q->queue[i]);
1057 else {
1058 /* Only the matching ones */
1059 for (i = 0; i < q->nr; i++) {
1060 struct diff_filepair *p = q->queue[i];
1062 if (((p->status == DIFF_STATUS_MODIFIED) &&
1063 ((p->score &&
1064 strchr(filter, DIFF_STATUS_FILTER_BROKEN)) ||
1065 (!p->score &&
1066 strchr(filter, DIFF_STATUS_MODIFIED)))) ||
1067 ((p->status != DIFF_STATUS_MODIFIED) &&
1068 strchr(filter, p->status)))
1069 diff_q(&outq, p);
1070 else
1071 diff_free_filepair(p);
1074 free(q->queue);
1075 *q = outq;
1078 void diffcore_std(const char **paths,
1079 int detect_rename, int rename_score,
1080 const char *pickaxe, int pickaxe_opts,
1081 int break_opt,
1082 const char *orderfile,
1083 const char *filter)
1085 if (paths && paths[0])
1086 diffcore_pathspec(paths);
1087 if (break_opt != -1)
1088 diffcore_break(break_opt);
1089 if (detect_rename)
1090 diffcore_rename(detect_rename, rename_score);
1091 if (break_opt != -1)
1092 diffcore_merge_broken();
1093 if (pickaxe)
1094 diffcore_pickaxe(pickaxe, pickaxe_opts);
1095 if (orderfile)
1096 diffcore_order(orderfile);
1097 diff_resolve_rename_copy();
1098 diffcore_apply_filter(filter);
1102 void diffcore_std_no_resolve(const char **paths,
1103 const char *pickaxe, int pickaxe_opts,
1104 const char *orderfile,
1105 const char *filter)
1107 if (paths && paths[0])
1108 diffcore_pathspec(paths);
1109 if (pickaxe)
1110 diffcore_pickaxe(pickaxe, pickaxe_opts);
1111 if (orderfile)
1112 diffcore_order(orderfile);
1113 diffcore_apply_filter(filter);
1116 void diff_addremove(int addremove, unsigned mode,
1117 const unsigned char *sha1,
1118 const char *base, const char *path)
1120 char concatpath[PATH_MAX];
1121 struct diff_filespec *one, *two;
1123 /* This may look odd, but it is a preparation for
1124 * feeding "there are unchanged files which should
1125 * not produce diffs, but when you are doing copy
1126 * detection you would need them, so here they are"
1127 * entries to the diff-core. They will be prefixed
1128 * with something like '=' or '*' (I haven't decided
1129 * which but should not make any difference).
1130 * Feeding the same new and old to diff_change()
1131 * also has the same effect.
1132 * Before the final output happens, they are pruned after
1133 * merged into rename/copy pairs as appropriate.
1135 if (reverse_diff)
1136 addremove = (addremove == '+' ? '-' :
1137 addremove == '-' ? '+' : addremove);
1139 if (!path) path = "";
1140 sprintf(concatpath, "%s%s", base, path);
1141 one = alloc_filespec(concatpath);
1142 two = alloc_filespec(concatpath);
1144 if (addremove != '+')
1145 fill_filespec(one, sha1, mode);
1146 if (addremove != '-')
1147 fill_filespec(two, sha1, mode);
1149 diff_queue(&diff_queued_diff, one, two);
1152 void diff_helper_input(unsigned old_mode,
1153 unsigned new_mode,
1154 const unsigned char *old_sha1,
1155 const unsigned char *new_sha1,
1156 const char *old_path,
1157 int status,
1158 int score,
1159 const char *new_path)
1161 struct diff_filespec *one, *two;
1162 struct diff_filepair *dp;
1164 one = alloc_filespec(old_path);
1165 two = alloc_filespec(new_path);
1166 if (old_mode)
1167 fill_filespec(one, old_sha1, old_mode);
1168 if (new_mode)
1169 fill_filespec(two, new_sha1, new_mode);
1170 dp = diff_queue(&diff_queued_diff, one, two);
1171 dp->score = score * MAX_SCORE / 100;
1172 dp->status = status;
1175 void diff_change(unsigned old_mode, unsigned new_mode,
1176 const unsigned char *old_sha1,
1177 const unsigned char *new_sha1,
1178 const char *base, const char *path)
1180 char concatpath[PATH_MAX];
1181 struct diff_filespec *one, *two;
1183 if (reverse_diff) {
1184 unsigned tmp;
1185 const unsigned char *tmp_c;
1186 tmp = old_mode; old_mode = new_mode; new_mode = tmp;
1187 tmp_c = old_sha1; old_sha1 = new_sha1; new_sha1 = tmp_c;
1189 if (!path) path = "";
1190 sprintf(concatpath, "%s%s", base, path);
1191 one = alloc_filespec(concatpath);
1192 two = alloc_filespec(concatpath);
1193 fill_filespec(one, old_sha1, old_mode);
1194 fill_filespec(two, new_sha1, new_mode);
1196 diff_queue(&diff_queued_diff, one, two);
1199 void diff_unmerge(const char *path)
1201 struct diff_filespec *one, *two;
1202 one = alloc_filespec(path);
1203 two = alloc_filespec(path);
1204 diff_queue(&diff_queued_diff, one, two);