Use git-update-ref in scripts.
[git/gitweb.git] / diff.c
blob9bded28729d6608f0449c483707f35279c24b1d5
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 use_size_cache;
17 static const char *external_diff(void)
19 static const char *external_diff_cmd = NULL;
20 static int done_preparing = 0;
21 const char *env_diff_opts;
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 external_diff_cmd = getenv("GIT_EXTERNAL_DIFF");
36 /* In case external diff fails... */
37 env_diff_opts = getenv("GIT_DIFF_OPTS");
38 if (env_diff_opts) diff_opts = env_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);
217 memset(spec, 0, sizeof(*spec));
218 spec->path = (char *)(spec + 1);
219 memcpy(spec->path, path, namelen+1);
220 return spec;
223 void fill_filespec(struct diff_filespec *spec, const unsigned char *sha1,
224 unsigned short mode)
226 if (mode) {
227 spec->mode = DIFF_FILE_CANON_MODE(mode);
228 memcpy(spec->sha1, sha1, 20);
229 spec->sha1_valid = !!memcmp(sha1, null_sha1, 20);
234 * Given a name and sha1 pair, if the dircache tells us the file in
235 * the work tree has that object contents, return true, so that
236 * prepare_temp_file() does not have to inflate and extract.
238 static int work_tree_matches(const char *name, const unsigned char *sha1)
240 struct cache_entry *ce;
241 struct stat st;
242 int pos, len;
244 /* We do not read the cache ourselves here, because the
245 * benchmark with my previous version that always reads cache
246 * shows that it makes things worse for diff-tree comparing
247 * two linux-2.6 kernel trees in an already checked out work
248 * tree. This is because most diff-tree comparisons deal with
249 * only a small number of files, while reading the cache is
250 * expensive for a large project, and its cost outweighs the
251 * savings we get by not inflating the object to a temporary
252 * file. Practically, this code only helps when we are used
253 * by diff-cache --cached, which does read the cache before
254 * calling us.
256 if (!active_cache)
257 return 0;
259 len = strlen(name);
260 pos = cache_name_pos(name, len);
261 if (pos < 0)
262 return 0;
263 ce = active_cache[pos];
264 if ((lstat(name, &st) < 0) ||
265 !S_ISREG(st.st_mode) || /* careful! */
266 ce_match_stat(ce, &st) ||
267 memcmp(sha1, ce->sha1, 20))
268 return 0;
269 /* we return 1 only when we can stat, it is a regular file,
270 * stat information matches, and sha1 recorded in the cache
271 * matches. I.e. we know the file in the work tree really is
272 * the same as the <name, sha1> pair.
274 return 1;
277 static struct sha1_size_cache {
278 unsigned char sha1[20];
279 unsigned long size;
280 } **sha1_size_cache;
281 static int sha1_size_cache_nr, sha1_size_cache_alloc;
283 static struct sha1_size_cache *locate_size_cache(unsigned char *sha1,
284 int find_only,
285 unsigned long size)
287 int first, last;
288 struct sha1_size_cache *e;
290 first = 0;
291 last = sha1_size_cache_nr;
292 while (last > first) {
293 int cmp, next = (last + first) >> 1;
294 e = sha1_size_cache[next];
295 cmp = memcmp(e->sha1, sha1, 20);
296 if (!cmp)
297 return e;
298 if (cmp < 0) {
299 last = next;
300 continue;
302 first = next+1;
304 /* not found */
305 if (find_only)
306 return NULL;
307 /* insert to make it at "first" */
308 if (sha1_size_cache_alloc <= sha1_size_cache_nr) {
309 sha1_size_cache_alloc = alloc_nr(sha1_size_cache_alloc);
310 sha1_size_cache = xrealloc(sha1_size_cache,
311 sha1_size_cache_alloc *
312 sizeof(*sha1_size_cache));
314 sha1_size_cache_nr++;
315 if (first < sha1_size_cache_nr)
316 memmove(sha1_size_cache + first + 1, sha1_size_cache + first,
317 (sha1_size_cache_nr - first - 1) *
318 sizeof(*sha1_size_cache));
319 e = xmalloc(sizeof(struct sha1_size_cache));
320 sha1_size_cache[first] = e;
321 memcpy(e->sha1, sha1, 20);
322 e->size = size;
323 return e;
327 * While doing rename detection and pickaxe operation, we may need to
328 * grab the data for the blob (or file) for our own in-core comparison.
329 * diff_filespec has data and size fields for this purpose.
331 int diff_populate_filespec(struct diff_filespec *s, int size_only)
333 int err = 0;
334 if (!DIFF_FILE_VALID(s))
335 die("internal error: asking to populate invalid file.");
336 if (S_ISDIR(s->mode))
337 return -1;
339 if (!use_size_cache)
340 size_only = 0;
342 if (s->data)
343 return err;
344 if (!s->sha1_valid ||
345 work_tree_matches(s->path, s->sha1)) {
346 struct stat st;
347 int fd;
348 if (lstat(s->path, &st) < 0) {
349 if (errno == ENOENT) {
350 err_empty:
351 err = -1;
352 empty:
353 s->data = "";
354 s->size = 0;
355 return err;
358 s->size = st.st_size;
359 if (!s->size)
360 goto empty;
361 if (size_only)
362 return 0;
363 if (S_ISLNK(st.st_mode)) {
364 int ret;
365 s->data = xmalloc(s->size);
366 s->should_free = 1;
367 ret = readlink(s->path, s->data, s->size);
368 if (ret < 0) {
369 free(s->data);
370 goto err_empty;
372 return 0;
374 fd = open(s->path, O_RDONLY);
375 if (fd < 0)
376 goto err_empty;
377 s->data = mmap(NULL, s->size, PROT_READ, MAP_PRIVATE, fd, 0);
378 close(fd);
379 if (s->data == MAP_FAILED)
380 goto err_empty;
381 s->should_munmap = 1;
383 else {
384 char type[20];
385 struct sha1_size_cache *e;
387 if (size_only) {
388 e = locate_size_cache(s->sha1, 1, 0);
389 if (e) {
390 s->size = e->size;
391 return 0;
393 if (!sha1_object_info(s->sha1, type, &s->size))
394 locate_size_cache(s->sha1, 0, s->size);
396 else {
397 s->data = read_sha1_file(s->sha1, type, &s->size);
398 s->should_free = 1;
401 return 0;
404 void diff_free_filespec_data(struct diff_filespec *s)
406 if (s->should_free)
407 free(s->data);
408 else if (s->should_munmap)
409 munmap(s->data, s->size);
410 s->should_free = s->should_munmap = 0;
411 s->data = NULL;
414 static void prep_temp_blob(struct diff_tempfile *temp,
415 void *blob,
416 unsigned long size,
417 unsigned char *sha1,
418 int mode)
420 int fd;
422 fd = git_mkstemp(temp->tmp_path, TEMPFILE_PATH_LEN, ".diff_XXXXXX");
423 if (fd < 0)
424 die("unable to create temp-file");
425 if (write(fd, blob, size) != size)
426 die("unable to write temp-file");
427 close(fd);
428 temp->name = temp->tmp_path;
429 strcpy(temp->hex, sha1_to_hex(sha1));
430 temp->hex[40] = 0;
431 sprintf(temp->mode, "%06o", mode);
434 static void prepare_temp_file(const char *name,
435 struct diff_tempfile *temp,
436 struct diff_filespec *one)
438 if (!DIFF_FILE_VALID(one)) {
439 not_a_valid_file:
440 /* A '-' entry produces this for file-2, and
441 * a '+' entry produces this for file-1.
443 temp->name = "/dev/null";
444 strcpy(temp->hex, ".");
445 strcpy(temp->mode, ".");
446 return;
449 if (!one->sha1_valid ||
450 work_tree_matches(name, one->sha1)) {
451 struct stat st;
452 if (lstat(name, &st) < 0) {
453 if (errno == ENOENT)
454 goto not_a_valid_file;
455 die("stat(%s): %s", name, strerror(errno));
457 if (S_ISLNK(st.st_mode)) {
458 int ret;
459 char *buf, buf_[1024];
460 buf = ((sizeof(buf_) < st.st_size) ?
461 xmalloc(st.st_size) : buf_);
462 ret = readlink(name, buf, st.st_size);
463 if (ret < 0)
464 die("readlink(%s)", name);
465 prep_temp_blob(temp, buf, st.st_size,
466 (one->sha1_valid ?
467 one->sha1 : null_sha1),
468 (one->sha1_valid ?
469 one->mode : S_IFLNK));
471 else {
472 /* we can borrow from the file in the work tree */
473 temp->name = name;
474 if (!one->sha1_valid)
475 strcpy(temp->hex, sha1_to_hex(null_sha1));
476 else
477 strcpy(temp->hex, sha1_to_hex(one->sha1));
478 /* Even though we may sometimes borrow the
479 * contents from the work tree, we always want
480 * one->mode. mode is trustworthy even when
481 * !(one->sha1_valid), as long as
482 * DIFF_FILE_VALID(one).
484 sprintf(temp->mode, "%06o", one->mode);
486 return;
488 else {
489 if (diff_populate_filespec(one, 0))
490 die("cannot read data blob for %s", one->path);
491 prep_temp_blob(temp, one->data, one->size,
492 one->sha1, one->mode);
496 static void remove_tempfile(void)
498 int i;
500 for (i = 0; i < 2; i++)
501 if (diff_temp[i].name == diff_temp[i].tmp_path) {
502 unlink(diff_temp[i].name);
503 diff_temp[i].name = NULL;
507 static void remove_tempfile_on_signal(int signo)
509 remove_tempfile();
512 /* An external diff command takes:
514 * diff-cmd name infile1 infile1-sha1 infile1-mode \
515 * infile2 infile2-sha1 infile2-mode [ rename-to ]
518 static void run_external_diff(const char *pgm,
519 const char *name,
520 const char *other,
521 struct diff_filespec *one,
522 struct diff_filespec *two,
523 const char *xfrm_msg,
524 int complete_rewrite)
526 struct diff_tempfile *temp = diff_temp;
527 pid_t pid;
528 int status;
529 static int atexit_asked = 0;
530 const char *othername;
532 othername = (other? other : name);
533 if (one && two) {
534 prepare_temp_file(name, &temp[0], one);
535 prepare_temp_file(othername, &temp[1], two);
536 if (! atexit_asked &&
537 (temp[0].name == temp[0].tmp_path ||
538 temp[1].name == temp[1].tmp_path)) {
539 atexit_asked = 1;
540 atexit(remove_tempfile);
542 signal(SIGINT, remove_tempfile_on_signal);
545 fflush(NULL);
546 pid = fork();
547 if (pid < 0)
548 die("unable to fork");
549 if (!pid) {
550 if (pgm) {
551 if (one && two) {
552 const char *exec_arg[10];
553 const char **arg = &exec_arg[0];
554 *arg++ = pgm;
555 *arg++ = name;
556 *arg++ = temp[0].name;
557 *arg++ = temp[0].hex;
558 *arg++ = temp[0].mode;
559 *arg++ = temp[1].name;
560 *arg++ = temp[1].hex;
561 *arg++ = temp[1].mode;
562 if (other) {
563 *arg++ = other;
564 *arg++ = xfrm_msg;
566 *arg = NULL;
567 execvp(pgm, (char *const*) exec_arg);
569 else
570 execlp(pgm, pgm, name, NULL);
573 * otherwise we use the built-in one.
575 if (one && two)
576 builtin_diff(name, othername, temp, xfrm_msg,
577 complete_rewrite);
578 else
579 printf("* Unmerged path %s\n", name);
580 exit(0);
582 if (waitpid(pid, &status, 0) < 0 ||
583 !WIFEXITED(status) || WEXITSTATUS(status)) {
584 /* Earlier we did not check the exit status because
585 * diff exits non-zero if files are different, and
586 * we are not interested in knowing that. It was a
587 * mistake which made it harder to quit a diff-*
588 * session that uses the git-apply-patch-script as
589 * the GIT_EXTERNAL_DIFF. A custom GIT_EXTERNAL_DIFF
590 * should also exit non-zero only when it wants to
591 * abort the entire diff-* session.
593 remove_tempfile();
594 fprintf(stderr, "external diff died, stopping at %s.\n", name);
595 exit(1);
597 remove_tempfile();
600 static void run_diff(struct diff_filepair *p)
602 const char *pgm = external_diff();
603 char msg_[PATH_MAX*2+200], *xfrm_msg;
604 struct diff_filespec *one;
605 struct diff_filespec *two;
606 const char *name;
607 const char *other;
608 int complete_rewrite = 0;
610 if (DIFF_PAIR_UNMERGED(p)) {
611 /* unmerged */
612 run_external_diff(pgm, p->one->path, NULL, NULL, NULL, NULL,
614 return;
617 name = p->one->path;
618 other = (strcmp(name, p->two->path) ? p->two->path : NULL);
619 one = p->one; two = p->two;
620 switch (p->status) {
621 case DIFF_STATUS_COPIED:
622 sprintf(msg_,
623 "similarity index %d%%\n"
624 "copy from %s\n"
625 "copy to %s",
626 (int)(0.5 + p->score * 100.0/MAX_SCORE),
627 name, other);
628 xfrm_msg = msg_;
629 break;
630 case DIFF_STATUS_RENAMED:
631 sprintf(msg_,
632 "similarity index %d%%\n"
633 "rename from %s\n"
634 "rename to %s",
635 (int)(0.5 + p->score * 100.0/MAX_SCORE),
636 name, other);
637 xfrm_msg = msg_;
638 break;
639 case DIFF_STATUS_MODIFIED:
640 if (p->score) {
641 sprintf(msg_,
642 "dissimilarity index %d%%",
643 (int)(0.5 + p->score * 100.0/MAX_SCORE));
644 xfrm_msg = msg_;
645 complete_rewrite = 1;
646 break;
648 /* fallthru */
649 default:
650 xfrm_msg = NULL;
653 if (!pgm &&
654 DIFF_FILE_VALID(one) && DIFF_FILE_VALID(two) &&
655 (S_IFMT & one->mode) != (S_IFMT & two->mode)) {
656 /* a filepair that changes between file and symlink
657 * needs to be split into deletion and creation.
659 struct diff_filespec *null = alloc_filespec(two->path);
660 run_external_diff(NULL, name, other, one, null, xfrm_msg, 0);
661 free(null);
662 null = alloc_filespec(one->path);
663 run_external_diff(NULL, name, other, null, two, xfrm_msg, 0);
664 free(null);
666 else
667 run_external_diff(pgm, name, other, one, two, xfrm_msg,
668 complete_rewrite);
671 void diff_setup(struct diff_options *options)
673 memset(options, 0, sizeof(*options));
674 options->output_format = DIFF_FORMAT_RAW;
675 options->line_termination = '\n';
676 options->break_opt = -1;
677 options->rename_limit = -1;
680 int diff_setup_done(struct diff_options *options)
682 if ((options->find_copies_harder || 0 <= options->rename_limit) &&
683 options->detect_rename != DIFF_DETECT_COPY)
684 return -1;
685 if (options->setup & DIFF_SETUP_USE_CACHE) {
686 if (!active_cache)
687 /* read-cache does not die even when it fails
688 * so it is safe for us to do this here. Also
689 * it does not smudge active_cache or active_nr
690 * when it fails, so we do not have to worry about
691 * cleaning it up oufselves either.
693 read_cache();
695 if (options->setup & DIFF_SETUP_USE_SIZE_CACHE)
696 use_size_cache = 1;
698 return 0;
701 int diff_opt_parse(struct diff_options *options, const char **av, int ac)
703 const char *arg = av[0];
704 if (!strcmp(arg, "-p") || !strcmp(arg, "-u"))
705 options->output_format = DIFF_FORMAT_PATCH;
706 else if (!strcmp(arg, "-z"))
707 options->line_termination = 0;
708 else if (!strncmp(arg, "-l", 2))
709 options->rename_limit = strtoul(arg+2, NULL, 10);
710 else if (!strcmp(arg, "--name-only"))
711 options->output_format = DIFF_FORMAT_NAME;
712 else if (!strcmp(arg, "--name-status"))
713 options->output_format = DIFF_FORMAT_NAME_STATUS;
714 else if (!strcmp(arg, "-R"))
715 options->reverse_diff = 1;
716 else if (!strncmp(arg, "-S", 2))
717 options->pickaxe = arg + 2;
718 else if (!strcmp(arg, "-s"))
719 options->output_format = DIFF_FORMAT_NO_OUTPUT;
720 else if (!strncmp(arg, "-O", 2))
721 options->orderfile = arg + 2;
722 else if (!strncmp(arg, "--diff-filter=", 14))
723 options->filter = arg + 14;
724 else if (!strcmp(arg, "--pickaxe-all"))
725 options->pickaxe_opts = DIFF_PICKAXE_ALL;
726 else if (!strncmp(arg, "-B", 2)) {
727 if ((options->break_opt =
728 diff_scoreopt_parse(arg)) == -1)
729 return -1;
731 else if (!strncmp(arg, "-M", 2)) {
732 if ((options->rename_score =
733 diff_scoreopt_parse(arg)) == -1)
734 return -1;
735 options->detect_rename = DIFF_DETECT_RENAME;
737 else if (!strncmp(arg, "-C", 2)) {
738 if ((options->rename_score =
739 diff_scoreopt_parse(arg)) == -1)
740 return -1;
741 options->detect_rename = DIFF_DETECT_COPY;
743 else if (!strcmp(arg, "--find-copies-harder"))
744 options->find_copies_harder = 1;
745 else
746 return 0;
747 return 1;
750 static int parse_num(const char **cp_p)
752 int num, scale, ch, cnt;
753 const char *cp = *cp_p;
755 cnt = num = 0;
756 scale = 1;
757 while ('0' <= (ch = *cp) && ch <= '9') {
758 if (cnt++ < 5) {
759 /* We simply ignore more than 5 digits precision. */
760 scale *= 10;
761 num = num * 10 + ch - '0';
763 cp++;
765 *cp_p = cp;
767 /* user says num divided by scale and we say internally that
768 * is MAX_SCORE * num / scale.
770 return (MAX_SCORE * num / scale);
773 int diff_scoreopt_parse(const char *opt)
775 int opt1, opt2, cmd;
777 if (*opt++ != '-')
778 return -1;
779 cmd = *opt++;
780 if (cmd != 'M' && cmd != 'C' && cmd != 'B')
781 return -1; /* that is not a -M, -C nor -B option */
783 opt1 = parse_num(&opt);
784 if (cmd != 'B')
785 opt2 = 0;
786 else {
787 if (*opt == 0)
788 opt2 = 0;
789 else if (*opt != '/')
790 return -1; /* we expect -B80/99 or -B80 */
791 else {
792 opt++;
793 opt2 = parse_num(&opt);
796 if (*opt != 0)
797 return -1;
798 return opt1 | (opt2 << 16);
801 struct diff_queue_struct diff_queued_diff;
803 void diff_q(struct diff_queue_struct *queue, struct diff_filepair *dp)
805 if (queue->alloc <= queue->nr) {
806 queue->alloc = alloc_nr(queue->alloc);
807 queue->queue = xrealloc(queue->queue,
808 sizeof(dp) * queue->alloc);
810 queue->queue[queue->nr++] = dp;
813 struct diff_filepair *diff_queue(struct diff_queue_struct *queue,
814 struct diff_filespec *one,
815 struct diff_filespec *two)
817 struct diff_filepair *dp = xmalloc(sizeof(*dp));
818 dp->one = one;
819 dp->two = two;
820 dp->score = 0;
821 dp->status = 0;
822 dp->source_stays = 0;
823 dp->broken_pair = 0;
824 if (queue)
825 diff_q(queue, dp);
826 return dp;
829 void diff_free_filepair(struct diff_filepair *p)
831 diff_free_filespec_data(p->one);
832 diff_free_filespec_data(p->two);
833 free(p->one);
834 free(p->two);
835 free(p);
838 static void diff_flush_raw(struct diff_filepair *p,
839 int line_termination,
840 int inter_name_termination,
841 int output_format)
843 int two_paths;
844 char status[10];
846 if (line_termination) {
847 const char *const err =
848 "path %s cannot be expressed without -z";
849 if (strchr(p->one->path, line_termination) ||
850 strchr(p->one->path, inter_name_termination))
851 die(err, p->one->path);
852 if (strchr(p->two->path, line_termination) ||
853 strchr(p->two->path, inter_name_termination))
854 die(err, p->two->path);
857 if (p->score)
858 sprintf(status, "%c%03d", p->status,
859 (int)(0.5 + p->score * 100.0/MAX_SCORE));
860 else {
861 status[0] = p->status;
862 status[1] = 0;
864 switch (p->status) {
865 case DIFF_STATUS_COPIED:
866 case DIFF_STATUS_RENAMED:
867 two_paths = 1;
868 break;
869 case DIFF_STATUS_ADDED:
870 case DIFF_STATUS_DELETED:
871 two_paths = 0;
872 break;
873 default:
874 two_paths = 0;
875 break;
877 if (output_format != DIFF_FORMAT_NAME_STATUS) {
878 printf(":%06o %06o %s ",
879 p->one->mode, p->two->mode, sha1_to_hex(p->one->sha1));
880 printf("%s ", sha1_to_hex(p->two->sha1));
882 printf("%s%c%s",status, inter_name_termination, p->one->path);
883 if (two_paths)
884 printf("%c%s", inter_name_termination, p->two->path);
885 putchar(line_termination);
888 static void diff_flush_name(struct diff_filepair *p,
889 int line_termination)
891 printf("%s%c", p->two->path, line_termination);
894 int diff_unmodified_pair(struct diff_filepair *p)
896 /* This function is written stricter than necessary to support
897 * the currently implemented transformers, but the idea is to
898 * let transformers to produce diff_filepairs any way they want,
899 * and filter and clean them up here before producing the output.
901 struct diff_filespec *one, *two;
903 if (DIFF_PAIR_UNMERGED(p))
904 return 0; /* unmerged is interesting */
906 one = p->one;
907 two = p->two;
909 /* deletion, addition, mode or type change
910 * and rename are all interesting.
912 if (DIFF_FILE_VALID(one) != DIFF_FILE_VALID(two) ||
913 DIFF_PAIR_MODE_CHANGED(p) ||
914 strcmp(one->path, two->path))
915 return 0;
917 /* both are valid and point at the same path. that is, we are
918 * dealing with a change.
920 if (one->sha1_valid && two->sha1_valid &&
921 !memcmp(one->sha1, two->sha1, sizeof(one->sha1)))
922 return 1; /* no change */
923 if (!one->sha1_valid && !two->sha1_valid)
924 return 1; /* both look at the same file on the filesystem. */
925 return 0;
928 static void diff_flush_patch(struct diff_filepair *p)
930 if (diff_unmodified_pair(p))
931 return;
933 if ((DIFF_FILE_VALID(p->one) && S_ISDIR(p->one->mode)) ||
934 (DIFF_FILE_VALID(p->two) && S_ISDIR(p->two->mode)))
935 return; /* no tree diffs in patch format */
937 run_diff(p);
940 int diff_queue_is_empty(void)
942 struct diff_queue_struct *q = &diff_queued_diff;
943 int i;
944 for (i = 0; i < q->nr; i++)
945 if (!diff_unmodified_pair(q->queue[i]))
946 return 0;
947 return 1;
950 #if DIFF_DEBUG
951 void diff_debug_filespec(struct diff_filespec *s, int x, const char *one)
953 fprintf(stderr, "queue[%d] %s (%s) %s %06o %s\n",
954 x, one ? one : "",
955 s->path,
956 DIFF_FILE_VALID(s) ? "valid" : "invalid",
957 s->mode,
958 s->sha1_valid ? sha1_to_hex(s->sha1) : "");
959 fprintf(stderr, "queue[%d] %s size %lu flags %d\n",
960 x, one ? one : "",
961 s->size, s->xfrm_flags);
964 void diff_debug_filepair(const struct diff_filepair *p, int i)
966 diff_debug_filespec(p->one, i, "one");
967 diff_debug_filespec(p->two, i, "two");
968 fprintf(stderr, "score %d, status %c stays %d broken %d\n",
969 p->score, p->status ? p->status : '?',
970 p->source_stays, p->broken_pair);
973 void diff_debug_queue(const char *msg, struct diff_queue_struct *q)
975 int i;
976 if (msg)
977 fprintf(stderr, "%s\n", msg);
978 fprintf(stderr, "q->nr = %d\n", q->nr);
979 for (i = 0; i < q->nr; i++) {
980 struct diff_filepair *p = q->queue[i];
981 diff_debug_filepair(p, i);
984 #endif
986 static void diff_resolve_rename_copy(void)
988 int i, j;
989 struct diff_filepair *p, *pp;
990 struct diff_queue_struct *q = &diff_queued_diff;
992 diff_debug_queue("resolve-rename-copy", q);
994 for (i = 0; i < q->nr; i++) {
995 p = q->queue[i];
996 p->status = 0; /* undecided */
997 if (DIFF_PAIR_UNMERGED(p))
998 p->status = DIFF_STATUS_UNMERGED;
999 else if (!DIFF_FILE_VALID(p->one))
1000 p->status = DIFF_STATUS_ADDED;
1001 else if (!DIFF_FILE_VALID(p->two))
1002 p->status = DIFF_STATUS_DELETED;
1003 else if (DIFF_PAIR_TYPE_CHANGED(p))
1004 p->status = DIFF_STATUS_TYPE_CHANGED;
1006 /* from this point on, we are dealing with a pair
1007 * whose both sides are valid and of the same type, i.e.
1008 * either in-place edit or rename/copy edit.
1010 else if (DIFF_PAIR_RENAME(p)) {
1011 if (p->source_stays) {
1012 p->status = DIFF_STATUS_COPIED;
1013 continue;
1015 /* See if there is some other filepair that
1016 * copies from the same source as us. If so
1017 * we are a copy. Otherwise we are either a
1018 * copy if the path stays, or a rename if it
1019 * does not, but we already handled "stays" case.
1021 for (j = i + 1; j < q->nr; j++) {
1022 pp = q->queue[j];
1023 if (strcmp(pp->one->path, p->one->path))
1024 continue; /* not us */
1025 if (!DIFF_PAIR_RENAME(pp))
1026 continue; /* not a rename/copy */
1027 /* pp is a rename/copy from the same source */
1028 p->status = DIFF_STATUS_COPIED;
1029 break;
1031 if (!p->status)
1032 p->status = DIFF_STATUS_RENAMED;
1034 else if (memcmp(p->one->sha1, p->two->sha1, 20) ||
1035 p->one->mode != p->two->mode)
1036 p->status = DIFF_STATUS_MODIFIED;
1037 else {
1038 /* This is a "no-change" entry and should not
1039 * happen anymore, but prepare for broken callers.
1041 error("feeding unmodified %s to diffcore",
1042 p->one->path);
1043 p->status = DIFF_STATUS_UNKNOWN;
1046 diff_debug_queue("resolve-rename-copy done", q);
1049 void diff_flush(struct diff_options *options)
1051 struct diff_queue_struct *q = &diff_queued_diff;
1052 int i;
1053 int inter_name_termination = '\t';
1054 int diff_output_format = options->output_format;
1055 int line_termination = options->line_termination;
1057 if (!line_termination)
1058 inter_name_termination = 0;
1060 for (i = 0; i < q->nr; i++) {
1061 struct diff_filepair *p = q->queue[i];
1062 if ((diff_output_format == DIFF_FORMAT_NO_OUTPUT) ||
1063 (p->status == DIFF_STATUS_UNKNOWN))
1064 continue;
1065 if (p->status == 0)
1066 die("internal error in diff-resolve-rename-copy");
1067 switch (diff_output_format) {
1068 case DIFF_FORMAT_PATCH:
1069 diff_flush_patch(p);
1070 break;
1071 case DIFF_FORMAT_RAW:
1072 case DIFF_FORMAT_NAME_STATUS:
1073 diff_flush_raw(p, line_termination,
1074 inter_name_termination,
1075 diff_output_format);
1076 break;
1077 case DIFF_FORMAT_NAME:
1078 diff_flush_name(p, line_termination);
1079 break;
1081 diff_free_filepair(q->queue[i]);
1083 free(q->queue);
1084 q->queue = NULL;
1085 q->nr = q->alloc = 0;
1088 static void diffcore_apply_filter(const char *filter)
1090 int i;
1091 struct diff_queue_struct *q = &diff_queued_diff;
1092 struct diff_queue_struct outq;
1093 outq.queue = NULL;
1094 outq.nr = outq.alloc = 0;
1096 if (!filter)
1097 return;
1099 if (strchr(filter, DIFF_STATUS_FILTER_AON)) {
1100 int found;
1101 for (i = found = 0; !found && i < q->nr; i++) {
1102 struct diff_filepair *p = q->queue[i];
1103 if (((p->status == DIFF_STATUS_MODIFIED) &&
1104 ((p->score &&
1105 strchr(filter, DIFF_STATUS_FILTER_BROKEN)) ||
1106 (!p->score &&
1107 strchr(filter, DIFF_STATUS_MODIFIED)))) ||
1108 ((p->status != DIFF_STATUS_MODIFIED) &&
1109 strchr(filter, p->status)))
1110 found++;
1112 if (found)
1113 return;
1115 /* otherwise we will clear the whole queue
1116 * by copying the empty outq at the end of this
1117 * function, but first clear the current entries
1118 * in the queue.
1120 for (i = 0; i < q->nr; i++)
1121 diff_free_filepair(q->queue[i]);
1123 else {
1124 /* Only the matching ones */
1125 for (i = 0; i < q->nr; i++) {
1126 struct diff_filepair *p = q->queue[i];
1128 if (((p->status == DIFF_STATUS_MODIFIED) &&
1129 ((p->score &&
1130 strchr(filter, DIFF_STATUS_FILTER_BROKEN)) ||
1131 (!p->score &&
1132 strchr(filter, DIFF_STATUS_MODIFIED)))) ||
1133 ((p->status != DIFF_STATUS_MODIFIED) &&
1134 strchr(filter, p->status)))
1135 diff_q(&outq, p);
1136 else
1137 diff_free_filepair(p);
1140 free(q->queue);
1141 *q = outq;
1144 void diffcore_std(struct diff_options *options)
1146 if (options->paths && options->paths[0])
1147 diffcore_pathspec(options->paths);
1148 if (options->break_opt != -1)
1149 diffcore_break(options->break_opt);
1150 if (options->detect_rename)
1151 diffcore_rename(options);
1152 if (options->break_opt != -1)
1153 diffcore_merge_broken();
1154 if (options->pickaxe)
1155 diffcore_pickaxe(options->pickaxe, options->pickaxe_opts);
1156 if (options->orderfile)
1157 diffcore_order(options->orderfile);
1158 diff_resolve_rename_copy();
1159 diffcore_apply_filter(options->filter);
1163 void diffcore_std_no_resolve(struct diff_options *options)
1165 if (options->pickaxe)
1166 diffcore_pickaxe(options->pickaxe, options->pickaxe_opts);
1167 if (options->orderfile)
1168 diffcore_order(options->orderfile);
1169 diffcore_apply_filter(options->filter);
1172 void diff_addremove(struct diff_options *options,
1173 int addremove, unsigned mode,
1174 const unsigned char *sha1,
1175 const char *base, const char *path)
1177 char concatpath[PATH_MAX];
1178 struct diff_filespec *one, *two;
1180 /* This may look odd, but it is a preparation for
1181 * feeding "there are unchanged files which should
1182 * not produce diffs, but when you are doing copy
1183 * detection you would need them, so here they are"
1184 * entries to the diff-core. They will be prefixed
1185 * with something like '=' or '*' (I haven't decided
1186 * which but should not make any difference).
1187 * Feeding the same new and old to diff_change()
1188 * also has the same effect.
1189 * Before the final output happens, they are pruned after
1190 * merged into rename/copy pairs as appropriate.
1192 if (options->reverse_diff)
1193 addremove = (addremove == '+' ? '-' :
1194 addremove == '-' ? '+' : addremove);
1196 if (!path) path = "";
1197 sprintf(concatpath, "%s%s", base, path);
1198 one = alloc_filespec(concatpath);
1199 two = alloc_filespec(concatpath);
1201 if (addremove != '+')
1202 fill_filespec(one, sha1, mode);
1203 if (addremove != '-')
1204 fill_filespec(two, sha1, mode);
1206 diff_queue(&diff_queued_diff, one, two);
1209 void diff_change(struct diff_options *options,
1210 unsigned old_mode, unsigned new_mode,
1211 const unsigned char *old_sha1,
1212 const unsigned char *new_sha1,
1213 const char *base, const char *path)
1215 char concatpath[PATH_MAX];
1216 struct diff_filespec *one, *two;
1218 if (options->reverse_diff) {
1219 unsigned tmp;
1220 const unsigned char *tmp_c;
1221 tmp = old_mode; old_mode = new_mode; new_mode = tmp;
1222 tmp_c = old_sha1; old_sha1 = new_sha1; new_sha1 = tmp_c;
1224 if (!path) path = "";
1225 sprintf(concatpath, "%s%s", base, path);
1226 one = alloc_filespec(concatpath);
1227 two = alloc_filespec(concatpath);
1228 fill_filespec(one, old_sha1, old_mode);
1229 fill_filespec(two, new_sha1, new_mode);
1231 diff_queue(&diff_queued_diff, one, two);
1234 void diff_unmerge(struct diff_options *options,
1235 const char *path)
1237 struct diff_filespec *one, *two;
1238 one = alloc_filespec(path);
1239 two = alloc_filespec(path);
1240 diff_queue(&diff_queued_diff, one, two);