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"
11
12static const char *diff_opts = "-pu";
13static unsigned char null_sha1[20] = { 0, };
14
15static int reverse_diff;
16static int use_size_cache;
17
18static const char *external_diff(void)
19{
20 static const char *external_diff_cmd = NULL;
21 static int done_preparing = 0;
22 const char *env_diff_opts;
23
24 if (done_preparing)
25 return external_diff_cmd;
26
27 /*
28 * Default values above are meant to match the
29 * Linux kernel development style. Examples of
30 * alternative styles you can specify via environment
31 * variables are:
32 *
33 * GIT_DIFF_OPTS="-c";
34 */
35 external_diff_cmd = getenv("GIT_EXTERNAL_DIFF");
36
37 /* In case external diff fails... */
38 env_diff_opts = getenv("GIT_DIFF_OPTS");
39 if (env_diff_opts) diff_opts = env_diff_opts;
40
41 done_preparing = 1;
42 return external_diff_cmd;
43}
44
45#define TEMPFILE_PATH_LEN 50
46
47static struct diff_tempfile {
48 const char *name; /* filename external diff should read from */
49 char hex[41];
50 char mode[10];
51 char tmp_path[TEMPFILE_PATH_LEN];
52} diff_temp[2];
53
54static int count_lines(const char *filename)
55{
56 FILE *in;
57 int count, ch, completely_empty = 1, nl_just_seen = 0;
58 in = fopen(filename, "r");
59 count = 0;
60 while ((ch = fgetc(in)) != EOF)
61 if (ch == '\n') {
62 count++;
63 nl_just_seen = 1;
64 completely_empty = 0;
65 }
66 else {
67 nl_just_seen = 0;
68 completely_empty = 0;
69 }
70 fclose(in);
71 if (completely_empty)
72 return 0;
73 if (!nl_just_seen)
74 count++; /* no trailing newline */
75 return count;
76}
77
78static void print_line_count(int count)
79{
80 switch (count) {
81 case 0:
82 printf("0,0");
83 break;
84 case 1:
85 printf("1");
86 break;
87 default:
88 printf("1,%d", count);
89 break;
90 }
91}
92
93static void copy_file(int prefix, const char *filename)
94{
95 FILE *in;
96 int ch, nl_just_seen = 1;
97 in = fopen(filename, "r");
98 while ((ch = fgetc(in)) != EOF) {
99 if (nl_just_seen)
100 putchar(prefix);
101 putchar(ch);
102 if (ch == '\n')
103 nl_just_seen = 1;
104 else
105 nl_just_seen = 0;
106 }
107 fclose(in);
108 if (!nl_just_seen)
109 printf("\n\\ No newline at end of file\n");
110}
111
112static void emit_rewrite_diff(const char *name_a,
113 const char *name_b,
114 struct diff_tempfile *temp)
115{
116 /* Use temp[i].name as input, name_a and name_b as labels */
117 int lc_a, lc_b;
118 lc_a = count_lines(temp[0].name);
119 lc_b = count_lines(temp[1].name);
120 printf("--- %s\n+++ %s\n@@ -", name_a, name_b);
121 print_line_count(lc_a);
122 printf(" +");
123 print_line_count(lc_b);
124 printf(" @@\n");
125 if (lc_a)
126 copy_file('-', temp[0].name);
127 if (lc_b)
128 copy_file('+', temp[1].name);
129}
130
131static void builtin_diff(const char *name_a,
132 const char *name_b,
133 struct diff_tempfile *temp,
134 const char *xfrm_msg,
135 int complete_rewrite)
136{
137 int i, next_at, cmd_size;
138 const char *const diff_cmd = "diff -L%s%s -L%s%s";
139 const char *const diff_arg = "%s %s||:"; /* "||:" is to return 0 */
140 const char *input_name_sq[2];
141 const char *path0[2];
142 const char *path1[2];
143 const char *name_sq[2];
144 char *cmd;
145
146 name_sq[0] = sq_quote(name_a);
147 name_sq[1] = sq_quote(name_b);
148
149 /* diff_cmd and diff_arg have 6 %s in total which makes
150 * the sum of these strings 12 bytes larger than required.
151 * we use 2 spaces around diff-opts, and we need to count
152 * terminating NUL, so we subtract 9 here.
153 */
154 cmd_size = (strlen(diff_cmd) + strlen(diff_opts) +
155 strlen(diff_arg) - 9);
156 for (i = 0; i < 2; i++) {
157 input_name_sq[i] = sq_quote(temp[i].name);
158 if (!strcmp(temp[i].name, "/dev/null")) {
159 path0[i] = "/dev/null";
160 path1[i] = "";
161 } else {
162 path0[i] = i ? "b/" : "a/";
163 path1[i] = name_sq[i];
164 }
165 cmd_size += (strlen(path0[i]) + strlen(path1[i]) +
166 strlen(input_name_sq[i]));
167 }
168
169 cmd = xmalloc(cmd_size);
170
171 next_at = 0;
172 next_at += snprintf(cmd+next_at, cmd_size-next_at,
173 diff_cmd,
174 path0[0], path1[0], path0[1], path1[1]);
175 next_at += snprintf(cmd+next_at, cmd_size-next_at,
176 " %s ", diff_opts);
177 next_at += snprintf(cmd+next_at, cmd_size-next_at,
178 diff_arg, input_name_sq[0], input_name_sq[1]);
179
180 printf("diff --git a/%s b/%s\n", name_a, name_b);
181 if (!path1[0][0]) {
182 printf("new file mode %s\n", temp[1].mode);
183 if (xfrm_msg && xfrm_msg[0])
184 puts(xfrm_msg);
185 }
186 else if (!path1[1][0]) {
187 printf("deleted file mode %s\n", temp[0].mode);
188 if (xfrm_msg && xfrm_msg[0])
189 puts(xfrm_msg);
190 }
191 else {
192 if (strcmp(temp[0].mode, temp[1].mode)) {
193 printf("old mode %s\n", temp[0].mode);
194 printf("new mode %s\n", temp[1].mode);
195 }
196 if (xfrm_msg && xfrm_msg[0])
197 puts(xfrm_msg);
198 if (strncmp(temp[0].mode, temp[1].mode, 3))
199 /* we do not run diff between different kind
200 * of objects.
201 */
202 exit(0);
203 if (complete_rewrite) {
204 fflush(NULL);
205 emit_rewrite_diff(name_a, name_b, temp);
206 exit(0);
207 }
208 }
209 fflush(NULL);
210 execlp("/bin/sh","sh", "-c", cmd, NULL);
211}
212
213struct diff_filespec *alloc_filespec(const char *path)
214{
215 int namelen = strlen(path);
216 struct diff_filespec *spec = xmalloc(sizeof(*spec) + namelen + 1);
217
218 memset(spec, 0, sizeof(*spec));
219 spec->path = (char *)(spec + 1);
220 memcpy(spec->path, path, namelen+1);
221 return spec;
222}
223
224void fill_filespec(struct diff_filespec *spec, const unsigned char *sha1,
225 unsigned short mode)
226{
227 if (mode) {
228 spec->mode = DIFF_FILE_CANON_MODE(mode);
229 memcpy(spec->sha1, sha1, 20);
230 spec->sha1_valid = !!memcmp(sha1, null_sha1, 20);
231 }
232}
233
234/*
235 * Given a name and sha1 pair, if the dircache tells us the file in
236 * the work tree has that object contents, return true, so that
237 * prepare_temp_file() does not have to inflate and extract.
238 */
239static int work_tree_matches(const char *name, const unsigned char *sha1)
240{
241 struct cache_entry *ce;
242 struct stat st;
243 int pos, len;
244
245 /* We do not read the cache ourselves here, because the
246 * benchmark with my previous version that always reads cache
247 * shows that it makes things worse for diff-tree comparing
248 * two linux-2.6 kernel trees in an already checked out work
249 * tree. This is because most diff-tree comparisons deal with
250 * only a small number of files, while reading the cache is
251 * expensive for a large project, and its cost outweighs the
252 * savings we get by not inflating the object to a temporary
253 * file. Practically, this code only helps when we are used
254 * by diff-cache --cached, which does read the cache before
255 * calling us.
256 */
257 if (!active_cache)
258 return 0;
259
260 len = strlen(name);
261 pos = cache_name_pos(name, len);
262 if (pos < 0)
263 return 0;
264 ce = active_cache[pos];
265 if ((lstat(name, &st) < 0) ||
266 !S_ISREG(st.st_mode) || /* careful! */
267 ce_match_stat(ce, &st) ||
268 memcmp(sha1, ce->sha1, 20))
269 return 0;
270 /* we return 1 only when we can stat, it is a regular file,
271 * stat information matches, and sha1 recorded in the cache
272 * matches. I.e. we know the file in the work tree really is
273 * the same as the <name, sha1> pair.
274 */
275 return 1;
276}
277
278static struct sha1_size_cache {
279 unsigned char sha1[20];
280 unsigned long size;
281} **sha1_size_cache;
282static int sha1_size_cache_nr, sha1_size_cache_alloc;
283
284static struct sha1_size_cache *locate_size_cache(unsigned char *sha1,
285 int find_only,
286 unsigned long size)
287{
288 int first, last;
289 struct sha1_size_cache *e;
290
291 first = 0;
292 last = sha1_size_cache_nr;
293 while (last > first) {
294 int cmp, next = (last + first) >> 1;
295 e = sha1_size_cache[next];
296 cmp = memcmp(e->sha1, sha1, 20);
297 if (!cmp)
298 return e;
299 if (cmp < 0) {
300 last = next;
301 continue;
302 }
303 first = next+1;
304 }
305 /* not found */
306 if (find_only)
307 return NULL;
308 /* insert to make it at "first" */
309 if (sha1_size_cache_alloc <= sha1_size_cache_nr) {
310 sha1_size_cache_alloc = alloc_nr(sha1_size_cache_alloc);
311 sha1_size_cache = xrealloc(sha1_size_cache,
312 sha1_size_cache_alloc *
313 sizeof(*sha1_size_cache));
314 }
315 sha1_size_cache_nr++;
316 if (first < sha1_size_cache_nr)
317 memmove(sha1_size_cache + first + 1, sha1_size_cache + first,
318 (sha1_size_cache_nr - first - 1) *
319 sizeof(*sha1_size_cache));
320 e = xmalloc(sizeof(struct sha1_size_cache));
321 sha1_size_cache[first] = e;
322 memcpy(e->sha1, sha1, 20);
323 e->size = size;
324 return e;
325}
326
327/*
328 * While doing rename detection and pickaxe operation, we may need to
329 * grab the data for the blob (or file) for our own in-core comparison.
330 * diff_filespec has data and size fields for this purpose.
331 */
332int diff_populate_filespec(struct diff_filespec *s, int size_only)
333{
334 int err = 0;
335 if (!DIFF_FILE_VALID(s))
336 die("internal error: asking to populate invalid file.");
337 if (S_ISDIR(s->mode))
338 return -1;
339
340 if (!use_size_cache)
341 size_only = 0;
342
343 if (s->data)
344 return err;
345 if (!s->sha1_valid ||
346 work_tree_matches(s->path, s->sha1)) {
347 struct stat st;
348 int fd;
349 if (lstat(s->path, &st) < 0) {
350 if (errno == ENOENT) {
351 err_empty:
352 err = -1;
353 empty:
354 s->data = "";
355 s->size = 0;
356 return err;
357 }
358 }
359 s->size = st.st_size;
360 if (!s->size)
361 goto empty;
362 if (size_only)
363 return 0;
364 if (S_ISLNK(st.st_mode)) {
365 int ret;
366 s->data = xmalloc(s->size);
367 s->should_free = 1;
368 ret = readlink(s->path, s->data, s->size);
369 if (ret < 0) {
370 free(s->data);
371 goto err_empty;
372 }
373 return 0;
374 }
375 fd = open(s->path, O_RDONLY);
376 if (fd < 0)
377 goto err_empty;
378 s->data = mmap(NULL, s->size, PROT_READ, MAP_PRIVATE, fd, 0);
379 close(fd);
380 if (s->data == MAP_FAILED)
381 goto err_empty;
382 s->should_munmap = 1;
383 }
384 else {
385 char type[20];
386 struct sha1_size_cache *e;
387
388 if (size_only) {
389 e = locate_size_cache(s->sha1, 1, 0);
390 if (e) {
391 s->size = e->size;
392 return 0;
393 }
394 if (!sha1_object_info(s->sha1, type, &s->size))
395 locate_size_cache(s->sha1, 0, s->size);
396 }
397 else {
398 s->data = read_sha1_file(s->sha1, type, &s->size);
399 s->should_free = 1;
400 }
401 }
402 return 0;
403}
404
405void diff_free_filespec_data(struct diff_filespec *s)
406{
407 if (s->should_free)
408 free(s->data);
409 else if (s->should_munmap)
410 munmap(s->data, s->size);
411 s->should_free = s->should_munmap = 0;
412 s->data = NULL;
413}
414
415static void prep_temp_blob(struct diff_tempfile *temp,
416 void *blob,
417 unsigned long size,
418 unsigned char *sha1,
419 int mode)
420{
421 int fd;
422
423 fd = git_mkstemp(temp->tmp_path, TEMPFILE_PATH_LEN, ".diff_XXXXXX");
424 if (fd < 0)
425 die("unable to create temp-file");
426 if (write(fd, blob, size) != size)
427 die("unable to write temp-file");
428 close(fd);
429 temp->name = temp->tmp_path;
430 strcpy(temp->hex, sha1_to_hex(sha1));
431 temp->hex[40] = 0;
432 sprintf(temp->mode, "%06o", mode);
433}
434
435static void prepare_temp_file(const char *name,
436 struct diff_tempfile *temp,
437 struct diff_filespec *one)
438{
439 if (!DIFF_FILE_VALID(one)) {
440 not_a_valid_file:
441 /* A '-' entry produces this for file-2, and
442 * a '+' entry produces this for file-1.
443 */
444 temp->name = "/dev/null";
445 strcpy(temp->hex, ".");
446 strcpy(temp->mode, ".");
447 return;
448 }
449
450 if (!one->sha1_valid ||
451 work_tree_matches(name, one->sha1)) {
452 struct stat st;
453 if (lstat(name, &st) < 0) {
454 if (errno == ENOENT)
455 goto not_a_valid_file;
456 die("stat(%s): %s", name, strerror(errno));
457 }
458 if (S_ISLNK(st.st_mode)) {
459 int ret;
460 char *buf, buf_[1024];
461 buf = ((sizeof(buf_) < st.st_size) ?
462 xmalloc(st.st_size) : buf_);
463 ret = readlink(name, buf, st.st_size);
464 if (ret < 0)
465 die("readlink(%s)", name);
466 prep_temp_blob(temp, buf, st.st_size,
467 (one->sha1_valid ?
468 one->sha1 : null_sha1),
469 (one->sha1_valid ?
470 one->mode : S_IFLNK));
471 }
472 else {
473 /* we can borrow from the file in the work tree */
474 temp->name = name;
475 if (!one->sha1_valid)
476 strcpy(temp->hex, sha1_to_hex(null_sha1));
477 else
478 strcpy(temp->hex, sha1_to_hex(one->sha1));
479 /* Even though we may sometimes borrow the
480 * contents from the work tree, we always want
481 * one->mode. mode is trustworthy even when
482 * !(one->sha1_valid), as long as
483 * DIFF_FILE_VALID(one).
484 */
485 sprintf(temp->mode, "%06o", one->mode);
486 }
487 return;
488 }
489 else {
490 if (diff_populate_filespec(one, 0))
491 die("cannot read data blob for %s", one->path);
492 prep_temp_blob(temp, one->data, one->size,
493 one->sha1, one->mode);
494 }
495}
496
497static void remove_tempfile(void)
498{
499 int i;
500
501 for (i = 0; i < 2; i++)
502 if (diff_temp[i].name == diff_temp[i].tmp_path) {
503 unlink(diff_temp[i].name);
504 diff_temp[i].name = NULL;
505 }
506}
507
508static void remove_tempfile_on_signal(int signo)
509{
510 remove_tempfile();
511}
512
513/* An external diff command takes:
514 *
515 * diff-cmd name infile1 infile1-sha1 infile1-mode \
516 * infile2 infile2-sha1 infile2-mode [ rename-to ]
517 *
518 */
519static void run_external_diff(const char *pgm,
520 const char *name,
521 const char *other,
522 struct diff_filespec *one,
523 struct diff_filespec *two,
524 const char *xfrm_msg,
525 int complete_rewrite)
526{
527 struct diff_tempfile *temp = diff_temp;
528 pid_t pid;
529 int status;
530 static int atexit_asked = 0;
531 const char *othername;
532
533 othername = (other? other : name);
534 if (one && two) {
535 prepare_temp_file(name, &temp[0], one);
536 prepare_temp_file(othername, &temp[1], two);
537 if (! atexit_asked &&
538 (temp[0].name == temp[0].tmp_path ||
539 temp[1].name == temp[1].tmp_path)) {
540 atexit_asked = 1;
541 atexit(remove_tempfile);
542 }
543 signal(SIGINT, remove_tempfile_on_signal);
544 }
545
546 fflush(NULL);
547 pid = fork();
548 if (pid < 0)
549 die("unable to fork");
550 if (!pid) {
551 if (pgm) {
552 if (one && two) {
553 const char *exec_arg[10];
554 const char **arg = &exec_arg[0];
555 *arg++ = pgm;
556 *arg++ = name;
557 *arg++ = temp[0].name;
558 *arg++ = temp[0].hex;
559 *arg++ = temp[0].mode;
560 *arg++ = temp[1].name;
561 *arg++ = temp[1].hex;
562 *arg++ = temp[1].mode;
563 if (other) {
564 *arg++ = other;
565 *arg++ = xfrm_msg;
566 }
567 *arg = NULL;
568 execvp(pgm, (char *const*) exec_arg);
569 }
570 else
571 execlp(pgm, pgm, name, NULL);
572 }
573 /*
574 * otherwise we use the built-in one.
575 */
576 if (one && two)
577 builtin_diff(name, othername, temp, xfrm_msg,
578 complete_rewrite);
579 else
580 printf("* Unmerged path %s\n", name);
581 exit(0);
582 }
583 if (waitpid(pid, &status, 0) < 0 ||
584 !WIFEXITED(status) || WEXITSTATUS(status)) {
585 /* Earlier we did not check the exit status because
586 * diff exits non-zero if files are different, and
587 * we are not interested in knowing that. It was a
588 * mistake which made it harder to quit a diff-*
589 * session that uses the git-apply-patch-script as
590 * the GIT_EXTERNAL_DIFF. A custom GIT_EXTERNAL_DIFF
591 * should also exit non-zero only when it wants to
592 * abort the entire diff-* session.
593 */
594 remove_tempfile();
595 fprintf(stderr, "external diff died, stopping at %s.\n", name);
596 exit(1);
597 }
598 remove_tempfile();
599}
600
601static void run_diff(struct diff_filepair *p)
602{
603 const char *pgm = external_diff();
604 char msg_[PATH_MAX*2+200], *xfrm_msg;
605 struct diff_filespec *one;
606 struct diff_filespec *two;
607 const char *name;
608 const char *other;
609 int complete_rewrite = 0;
610
611 if (DIFF_PAIR_UNMERGED(p)) {
612 /* unmerged */
613 run_external_diff(pgm, p->one->path, NULL, NULL, NULL, NULL,
614 0);
615 return;
616 }
617
618 name = p->one->path;
619 other = (strcmp(name, p->two->path) ? p->two->path : NULL);
620 one = p->one; two = p->two;
621 switch (p->status) {
622 case DIFF_STATUS_COPIED:
623 sprintf(msg_,
624 "similarity index %d%%\n"
625 "copy from %s\n"
626 "copy to %s",
627 (int)(0.5 + p->score * 100.0/MAX_SCORE),
628 name, other);
629 xfrm_msg = msg_;
630 break;
631 case DIFF_STATUS_RENAMED:
632 sprintf(msg_,
633 "similarity index %d%%\n"
634 "rename from %s\n"
635 "rename to %s",
636 (int)(0.5 + p->score * 100.0/MAX_SCORE),
637 name, other);
638 xfrm_msg = msg_;
639 break;
640 case DIFF_STATUS_MODIFIED:
641 if (p->score) {
642 sprintf(msg_,
643 "dissimilarity index %d%%",
644 (int)(0.5 + p->score * 100.0/MAX_SCORE));
645 xfrm_msg = msg_;
646 complete_rewrite = 1;
647 break;
648 }
649 /* fallthru */
650 default:
651 xfrm_msg = NULL;
652 }
653
654 if (!pgm &&
655 DIFF_FILE_VALID(one) && DIFF_FILE_VALID(two) &&
656 (S_IFMT & one->mode) != (S_IFMT & two->mode)) {
657 /* a filepair that changes between file and symlink
658 * needs to be split into deletion and creation.
659 */
660 struct diff_filespec *null = alloc_filespec(two->path);
661 run_external_diff(NULL, name, other, one, null, xfrm_msg, 0);
662 free(null);
663 null = alloc_filespec(one->path);
664 run_external_diff(NULL, name, other, null, two, xfrm_msg, 0);
665 free(null);
666 }
667 else
668 run_external_diff(pgm, name, other, one, two, xfrm_msg,
669 complete_rewrite);
670}
671
672void diff_setup(int flags)
673{
674 if (flags & DIFF_SETUP_REVERSE)
675 reverse_diff = 1;
676 if (flags & DIFF_SETUP_USE_CACHE) {
677 if (!active_cache)
678 /* read-cache does not die even when it fails
679 * so it is safe for us to do this here. Also
680 * it does not smudge active_cache or active_nr
681 * when it fails, so we do not have to worry about
682 * cleaning it up oufselves either.
683 */
684 read_cache();
685 }
686 if (flags & DIFF_SETUP_USE_SIZE_CACHE)
687 use_size_cache = 1;
688
689}
690
691static int parse_num(const char **cp_p)
692{
693 int num, scale, ch, cnt;
694 const char *cp = *cp_p;
695
696 cnt = num = 0;
697 scale = 1;
698 while ('0' <= (ch = *cp) && ch <= '9') {
699 if (cnt++ < 5) {
700 /* We simply ignore more than 5 digits precision. */
701 scale *= 10;
702 num = num * 10 + ch - '0';
703 }
704 cp++;
705 }
706 *cp_p = cp;
707
708 /* user says num divided by scale and we say internally that
709 * is MAX_SCORE * num / scale.
710 */
711 return (MAX_SCORE * num / scale);
712}
713
714int diff_scoreopt_parse(const char *opt)
715{
716 int opt1, opt2, cmd;
717
718 if (*opt++ != '-')
719 return -1;
720 cmd = *opt++;
721 if (cmd != 'M' && cmd != 'C' && cmd != 'B')
722 return -1; /* that is not a -M, -C nor -B option */
723
724 opt1 = parse_num(&opt);
725 if (cmd != 'B')
726 opt2 = 0;
727 else {
728 if (*opt == 0)
729 opt2 = 0;
730 else if (*opt != '/')
731 return -1; /* we expect -B80/99 or -B80 */
732 else {
733 opt++;
734 opt2 = parse_num(&opt);
735 }
736 }
737 if (*opt != 0)
738 return -1;
739 return opt1 | (opt2 << 16);
740}
741
742struct diff_queue_struct diff_queued_diff;
743
744void diff_q(struct diff_queue_struct *queue, struct diff_filepair *dp)
745{
746 if (queue->alloc <= queue->nr) {
747 queue->alloc = alloc_nr(queue->alloc);
748 queue->queue = xrealloc(queue->queue,
749 sizeof(dp) * queue->alloc);
750 }
751 queue->queue[queue->nr++] = dp;
752}
753
754struct diff_filepair *diff_queue(struct diff_queue_struct *queue,
755 struct diff_filespec *one,
756 struct diff_filespec *two)
757{
758 struct diff_filepair *dp = xmalloc(sizeof(*dp));
759 dp->one = one;
760 dp->two = two;
761 dp->score = 0;
762 dp->status = 0;
763 dp->source_stays = 0;
764 dp->broken_pair = 0;
765 if (queue)
766 diff_q(queue, dp);
767 return dp;
768}
769
770void diff_free_filepair(struct diff_filepair *p)
771{
772 diff_free_filespec_data(p->one);
773 diff_free_filespec_data(p->two);
774 free(p->one);
775 free(p->two);
776 free(p);
777}
778
779static void diff_flush_raw(struct diff_filepair *p,
780 int line_termination,
781 int inter_name_termination)
782{
783 int two_paths;
784 char status[10];
785
786 if (line_termination) {
787 const char *const err =
788 "path %s cannot be expressed without -z";
789 if (strchr(p->one->path, line_termination) ||
790 strchr(p->one->path, inter_name_termination))
791 die(err, p->one->path);
792 if (strchr(p->two->path, line_termination) ||
793 strchr(p->two->path, inter_name_termination))
794 die(err, p->two->path);
795 }
796
797 if (p->score)
798 sprintf(status, "%c%03d", p->status,
799 (int)(0.5 + p->score * 100.0/MAX_SCORE));
800 else {
801 status[0] = p->status;
802 status[1] = 0;
803 }
804 switch (p->status) {
805 case DIFF_STATUS_COPIED:
806 case DIFF_STATUS_RENAMED:
807 two_paths = 1;
808 break;
809 case DIFF_STATUS_ADDED:
810 case DIFF_STATUS_DELETED:
811 two_paths = 0;
812 break;
813 default:
814 two_paths = 0;
815 break;
816 }
817 printf(":%06o %06o %s ",
818 p->one->mode, p->two->mode, sha1_to_hex(p->one->sha1));
819 printf("%s %s%c%s",
820 sha1_to_hex(p->two->sha1),
821 status,
822 inter_name_termination,
823 p->one->path);
824 if (two_paths)
825 printf("%c%s", inter_name_termination, p->two->path);
826 putchar(line_termination);
827}
828
829static void diff_flush_name(struct diff_filepair *p,
830 int line_termination)
831{
832 printf("%s%c", p->two->path, line_termination);
833}
834
835int diff_unmodified_pair(struct diff_filepair *p)
836{
837 /* This function is written stricter than necessary to support
838 * the currently implemented transformers, but the idea is to
839 * let transformers to produce diff_filepairs any way they want,
840 * and filter and clean them up here before producing the output.
841 */
842 struct diff_filespec *one, *two;
843
844 if (DIFF_PAIR_UNMERGED(p))
845 return 0; /* unmerged is interesting */
846
847 one = p->one;
848 two = p->two;
849
850 /* deletion, addition, mode or type change
851 * and rename are all interesting.
852 */
853 if (DIFF_FILE_VALID(one) != DIFF_FILE_VALID(two) ||
854 DIFF_PAIR_MODE_CHANGED(p) ||
855 strcmp(one->path, two->path))
856 return 0;
857
858 /* both are valid and point at the same path. that is, we are
859 * dealing with a change.
860 */
861 if (one->sha1_valid && two->sha1_valid &&
862 !memcmp(one->sha1, two->sha1, sizeof(one->sha1)))
863 return 1; /* no change */
864 if (!one->sha1_valid && !two->sha1_valid)
865 return 1; /* both look at the same file on the filesystem. */
866 return 0;
867}
868
869static void diff_flush_patch(struct diff_filepair *p)
870{
871 if (diff_unmodified_pair(p))
872 return;
873
874 if ((DIFF_FILE_VALID(p->one) && S_ISDIR(p->one->mode)) ||
875 (DIFF_FILE_VALID(p->two) && S_ISDIR(p->two->mode)))
876 return; /* no tree diffs in patch format */
877
878 run_diff(p);
879}
880
881int diff_queue_is_empty(void)
882{
883 struct diff_queue_struct *q = &diff_queued_diff;
884 int i;
885 for (i = 0; i < q->nr; i++)
886 if (!diff_unmodified_pair(q->queue[i]))
887 return 0;
888 return 1;
889}
890
891#if DIFF_DEBUG
892void diff_debug_filespec(struct diff_filespec *s, int x, const char *one)
893{
894 fprintf(stderr, "queue[%d] %s (%s) %s %06o %s\n",
895 x, one ? one : "",
896 s->path,
897 DIFF_FILE_VALID(s) ? "valid" : "invalid",
898 s->mode,
899 s->sha1_valid ? sha1_to_hex(s->sha1) : "");
900 fprintf(stderr, "queue[%d] %s size %lu flags %d\n",
901 x, one ? one : "",
902 s->size, s->xfrm_flags);
903}
904
905void diff_debug_filepair(const struct diff_filepair *p, int i)
906{
907 diff_debug_filespec(p->one, i, "one");
908 diff_debug_filespec(p->two, i, "two");
909 fprintf(stderr, "score %d, status %c stays %d broken %d\n",
910 p->score, p->status ? p->status : '?',
911 p->source_stays, p->broken_pair);
912}
913
914void diff_debug_queue(const char *msg, struct diff_queue_struct *q)
915{
916 int i;
917 if (msg)
918 fprintf(stderr, "%s\n", msg);
919 fprintf(stderr, "q->nr = %d\n", q->nr);
920 for (i = 0; i < q->nr; i++) {
921 struct diff_filepair *p = q->queue[i];
922 diff_debug_filepair(p, i);
923 }
924}
925#endif
926
927static void diff_resolve_rename_copy(void)
928{
929 int i, j;
930 struct diff_filepair *p, *pp;
931 struct diff_queue_struct *q = &diff_queued_diff;
932
933 diff_debug_queue("resolve-rename-copy", q);
934
935 for (i = 0; i < q->nr; i++) {
936 p = q->queue[i];
937 p->status = 0; /* undecided */
938 if (DIFF_PAIR_UNMERGED(p))
939 p->status = DIFF_STATUS_UNMERGED;
940 else if (!DIFF_FILE_VALID(p->one))
941 p->status = DIFF_STATUS_ADDED;
942 else if (!DIFF_FILE_VALID(p->two))
943 p->status = DIFF_STATUS_DELETED;
944 else if (DIFF_PAIR_TYPE_CHANGED(p))
945 p->status = DIFF_STATUS_TYPE_CHANGED;
946
947 /* from this point on, we are dealing with a pair
948 * whose both sides are valid and of the same type, i.e.
949 * either in-place edit or rename/copy edit.
950 */
951 else if (DIFF_PAIR_RENAME(p)) {
952 if (p->source_stays) {
953 p->status = DIFF_STATUS_COPIED;
954 continue;
955 }
956 /* See if there is some other filepair that
957 * copies from the same source as us. If so
958 * we are a copy. Otherwise we are either a
959 * copy if the path stays, or a rename if it
960 * does not, but we already handled "stays" case.
961 */
962 for (j = i + 1; j < q->nr; j++) {
963 pp = q->queue[j];
964 if (strcmp(pp->one->path, p->one->path))
965 continue; /* not us */
966 if (!DIFF_PAIR_RENAME(pp))
967 continue; /* not a rename/copy */
968 /* pp is a rename/copy from the same source */
969 p->status = DIFF_STATUS_COPIED;
970 break;
971 }
972 if (!p->status)
973 p->status = DIFF_STATUS_RENAMED;
974 }
975 else if (memcmp(p->one->sha1, p->two->sha1, 20) ||
976 p->one->mode != p->two->mode)
977 p->status = DIFF_STATUS_MODIFIED;
978 else {
979 /* This is a "no-change" entry and should not
980 * happen anymore, but prepare for broken callers.
981 */
982 error("feeding unmodified %s to diffcore",
983 p->one->path);
984 p->status = DIFF_STATUS_UNKNOWN;
985 }
986 }
987 diff_debug_queue("resolve-rename-copy done", q);
988}
989
990void diff_flush(int diff_output_style, int line_termination)
991{
992 struct diff_queue_struct *q = &diff_queued_diff;
993 int i;
994 int inter_name_termination = '\t';
995
996 if (!line_termination)
997 inter_name_termination = 0;
998
999 for (i = 0; i < q->nr; i++) {
1000 struct diff_filepair *p = q->queue[i];
1001 if ((diff_output_style == DIFF_FORMAT_NO_OUTPUT) ||
1002 (p->status == DIFF_STATUS_UNKNOWN))
1003 continue;
1004 if (p->status == 0)
1005 die("internal error in diff-resolve-rename-copy");
1006 switch (diff_output_style) {
1007 case DIFF_FORMAT_PATCH:
1008 diff_flush_patch(p);
1009 break;
1010 case DIFF_FORMAT_RAW:
1011 diff_flush_raw(p, line_termination,
1012 inter_name_termination);
1013 break;
1014 case DIFF_FORMAT_NAME:
1015 diff_flush_name(p, line_termination);
1016 break;
1017 }
1018 diff_free_filepair(q->queue[i]);
1019 }
1020 free(q->queue);
1021 q->queue = NULL;
1022 q->nr = q->alloc = 0;
1023}
1024
1025static void diffcore_apply_filter(const char *filter)
1026{
1027 int i;
1028 struct diff_queue_struct *q = &diff_queued_diff;
1029 struct diff_queue_struct outq;
1030 outq.queue = NULL;
1031 outq.nr = outq.alloc = 0;
1032
1033 if (!filter)
1034 return;
1035
1036 if (strchr(filter, DIFF_STATUS_FILTER_AON)) {
1037 int found;
1038 for (i = found = 0; !found && i < q->nr; i++) {
1039 struct diff_filepair *p = q->queue[i];
1040 if (((p->status == DIFF_STATUS_MODIFIED) &&
1041 ((p->score &&
1042 strchr(filter, DIFF_STATUS_FILTER_BROKEN)) ||
1043 (!p->score &&
1044 strchr(filter, DIFF_STATUS_MODIFIED)))) ||
1045 ((p->status != DIFF_STATUS_MODIFIED) &&
1046 strchr(filter, p->status)))
1047 found++;
1048 }
1049 if (found)
1050 return;
1051
1052 /* otherwise we will clear the whole queue
1053 * by copying the empty outq at the end of this
1054 * function, but first clear the current entries
1055 * in the queue.
1056 */
1057 for (i = 0; i < q->nr; i++)
1058 diff_free_filepair(q->queue[i]);
1059 }
1060 else {
1061 /* Only the matching ones */
1062 for (i = 0; i < q->nr; i++) {
1063 struct diff_filepair *p = q->queue[i];
1064
1065 if (((p->status == DIFF_STATUS_MODIFIED) &&
1066 ((p->score &&
1067 strchr(filter, DIFF_STATUS_FILTER_BROKEN)) ||
1068 (!p->score &&
1069 strchr(filter, DIFF_STATUS_MODIFIED)))) ||
1070 ((p->status != DIFF_STATUS_MODIFIED) &&
1071 strchr(filter, p->status)))
1072 diff_q(&outq, p);
1073 else
1074 diff_free_filepair(p);
1075 }
1076 }
1077 free(q->queue);
1078 *q = outq;
1079}
1080
1081void diffcore_std(const char **paths,
1082 int detect_rename, int rename_score,
1083 const char *pickaxe, int pickaxe_opts,
1084 int break_opt,
1085 const char *orderfile,
1086 const char *filter)
1087{
1088 if (paths && paths[0])
1089 diffcore_pathspec(paths);
1090 if (break_opt != -1)
1091 diffcore_break(break_opt);
1092 if (detect_rename)
1093 diffcore_rename(detect_rename, rename_score);
1094 if (break_opt != -1)
1095 diffcore_merge_broken();
1096 if (pickaxe)
1097 diffcore_pickaxe(pickaxe, pickaxe_opts);
1098 if (orderfile)
1099 diffcore_order(orderfile);
1100 diff_resolve_rename_copy();
1101 diffcore_apply_filter(filter);
1102}
1103
1104
1105void diffcore_std_no_resolve(const char **paths,
1106 const char *pickaxe, int pickaxe_opts,
1107 const char *orderfile,
1108 const char *filter)
1109{
1110 if (paths && paths[0])
1111 diffcore_pathspec(paths);
1112 if (pickaxe)
1113 diffcore_pickaxe(pickaxe, pickaxe_opts);
1114 if (orderfile)
1115 diffcore_order(orderfile);
1116 diffcore_apply_filter(filter);
1117}
1118
1119void diff_addremove(int addremove, unsigned mode,
1120 const unsigned char *sha1,
1121 const char *base, const char *path)
1122{
1123 char concatpath[PATH_MAX];
1124 struct diff_filespec *one, *two;
1125
1126 /* This may look odd, but it is a preparation for
1127 * feeding "there are unchanged files which should
1128 * not produce diffs, but when you are doing copy
1129 * detection you would need them, so here they are"
1130 * entries to the diff-core. They will be prefixed
1131 * with something like '=' or '*' (I haven't decided
1132 * which but should not make any difference).
1133 * Feeding the same new and old to diff_change()
1134 * also has the same effect.
1135 * Before the final output happens, they are pruned after
1136 * merged into rename/copy pairs as appropriate.
1137 */
1138 if (reverse_diff)
1139 addremove = (addremove == '+' ? '-' :
1140 addremove == '-' ? '+' : addremove);
1141
1142 if (!path) path = "";
1143 sprintf(concatpath, "%s%s", base, path);
1144 one = alloc_filespec(concatpath);
1145 two = alloc_filespec(concatpath);
1146
1147 if (addremove != '+')
1148 fill_filespec(one, sha1, mode);
1149 if (addremove != '-')
1150 fill_filespec(two, sha1, mode);
1151
1152 diff_queue(&diff_queued_diff, one, two);
1153}
1154
1155void diff_change(unsigned old_mode, unsigned new_mode,
1156 const unsigned char *old_sha1,
1157 const unsigned char *new_sha1,
1158 const char *base, const char *path)
1159{
1160 char concatpath[PATH_MAX];
1161 struct diff_filespec *one, *two;
1162
1163 if (reverse_diff) {
1164 unsigned tmp;
1165 const unsigned char *tmp_c;
1166 tmp = old_mode; old_mode = new_mode; new_mode = tmp;
1167 tmp_c = old_sha1; old_sha1 = new_sha1; new_sha1 = tmp_c;
1168 }
1169 if (!path) path = "";
1170 sprintf(concatpath, "%s%s", base, path);
1171 one = alloc_filespec(concatpath);
1172 two = alloc_filespec(concatpath);
1173 fill_filespec(one, old_sha1, old_mode);
1174 fill_filespec(two, new_sha1, new_mode);
1175
1176 diff_queue(&diff_queued_diff, one, two);
1177}
1178
1179void diff_unmerge(const char *path)
1180{
1181 struct diff_filespec *one, *two;
1182 one = alloc_filespec(path);
1183 two = alloc_filespec(path);
1184 diff_queue(&diff_queued_diff, one, two);
1185}