[PATCH] RPM spec updates.
[git/dscho.git] / apply.c
blobc671d9e86cc04e2c6756212e3496c4ef5db8207a
1 /*
2 * apply.c
4 * Copyright (C) Linus Torvalds, 2005
6 * This applies patches on top of some (arbitrary) version of the SCM.
8 * NOTE! It does all its work in the index file, and only cares about
9 * the files in the working directory if you tell it to "merge" the
10 * patch apply.
12 * Even when merging it always takes the source from the index, and
13 * uses the working tree as a "branch" for a 3-way merge.
15 #include <ctype.h>
16 #include <fnmatch.h>
17 #include "cache.h"
19 // We default to the merge behaviour, since that's what most people would
20 // expect.
22 // --check turns on checking that the working tree matches the
23 // files that are being modified, but doesn't apply the patch
24 // --stat does just a diffstat, and doesn't actually apply
25 // --show-files shows the directory changes
27 static int merge_patch = 1;
28 static int check_index = 0;
29 static int write_index = 0;
30 static int diffstat = 0;
31 static int summary = 0;
32 static int check = 0;
33 static int apply = 1;
34 static int show_files = 0;
35 static const char apply_usage[] =
36 "git-apply [--no-merge] [--stat] [--summary] [--check] [--index] [--apply] [--show-files] <patch>...";
39 * For "diff-stat" like behaviour, we keep track of the biggest change
40 * we've seen, and the longest filename. That allows us to do simple
41 * scaling.
43 static int max_change, max_len;
46 * Various "current state", notably line numbers and what
47 * file (and how) we're patching right now.. The "is_xxxx"
48 * things are flags, where -1 means "don't know yet".
50 static int linenr = 1;
52 struct fragment {
53 unsigned long oldpos, oldlines;
54 unsigned long newpos, newlines;
55 const char *patch;
56 int size;
57 struct fragment *next;
60 struct patch {
61 char *new_name, *old_name, *def_name;
62 unsigned int old_mode, new_mode;
63 int is_rename, is_copy, is_new, is_delete;
64 int lines_added, lines_deleted;
65 int score;
66 struct fragment *fragments;
67 char *result;
68 unsigned long resultsize;
69 struct patch *next;
72 #define CHUNKSIZE (8192)
73 #define SLOP (16)
75 static void *read_patch_file(int fd, unsigned long *sizep)
77 unsigned long size = 0, alloc = CHUNKSIZE;
78 void *buffer = xmalloc(alloc);
80 for (;;) {
81 int nr = alloc - size;
82 if (nr < 1024) {
83 alloc += CHUNKSIZE;
84 buffer = xrealloc(buffer, alloc);
85 nr = alloc - size;
87 nr = read(fd, buffer + size, nr);
88 if (!nr)
89 break;
90 if (nr < 0) {
91 if (errno == EAGAIN)
92 continue;
93 die("git-apply: read returned %s", strerror(errno));
95 size += nr;
97 *sizep = size;
100 * Make sure that we have some slop in the buffer
101 * so that we can do speculative "memcmp" etc, and
102 * see to it that it is NUL-filled.
104 if (alloc < size + SLOP)
105 buffer = xrealloc(buffer, size + SLOP);
106 memset(buffer + size, 0, SLOP);
107 return buffer;
110 static unsigned long linelen(const char *buffer, unsigned long size)
112 unsigned long len = 0;
113 while (size--) {
114 len++;
115 if (*buffer++ == '\n')
116 break;
118 return len;
121 static int is_dev_null(const char *str)
123 return !memcmp("/dev/null", str, 9) && isspace(str[9]);
126 #define TERM_SPACE 1
127 #define TERM_TAB 2
129 static int name_terminate(const char *name, int namelen, int c, int terminate)
131 if (c == ' ' && !(terminate & TERM_SPACE))
132 return 0;
133 if (c == '\t' && !(terminate & TERM_TAB))
134 return 0;
136 return 1;
139 static char * find_name(const char *line, char *def, int p_value, int terminate)
141 int len;
142 const char *start = line;
143 char *name;
145 for (;;) {
146 char c = *line;
148 if (isspace(c)) {
149 if (c == '\n')
150 break;
151 if (name_terminate(start, line-start, c, terminate))
152 break;
154 line++;
155 if (c == '/' && !--p_value)
156 start = line;
158 if (!start)
159 return def;
160 len = line - start;
161 if (!len)
162 return def;
165 * Generally we prefer the shorter name, especially
166 * if the other one is just a variation of that with
167 * something else tacked on to the end (ie "file.orig"
168 * or "file~").
170 if (def) {
171 int deflen = strlen(def);
172 if (deflen < len && !strncmp(start, def, deflen))
173 return def;
176 name = xmalloc(len + 1);
177 memcpy(name, start, len);
178 name[len] = 0;
179 free(def);
180 return name;
184 * Get the name etc info from the --/+++ lines of a traditional patch header
186 * NOTE! This hardcodes "-p1" behaviour in filename detection.
188 * FIXME! The end-of-filename heuristics are kind of screwy. For existing
189 * files, we can happily check the index for a match, but for creating a
190 * new file we should try to match whatever "patch" does. I have no idea.
192 static void parse_traditional_patch(const char *first, const char *second, struct patch *patch)
194 int p_value = 1;
195 char *name;
197 first += 4; // skip "--- "
198 second += 4; // skip "+++ "
199 if (is_dev_null(first)) {
200 patch->is_new = 1;
201 patch->is_delete = 0;
202 name = find_name(second, NULL, p_value, TERM_SPACE | TERM_TAB);
203 patch->new_name = name;
204 } else if (is_dev_null(second)) {
205 patch->is_new = 0;
206 patch->is_delete = 1;
207 name = find_name(first, NULL, p_value, TERM_SPACE | TERM_TAB);
208 patch->old_name = name;
209 } else {
210 name = find_name(first, NULL, p_value, TERM_SPACE | TERM_TAB);
211 name = find_name(second, name, p_value, TERM_SPACE | TERM_TAB);
212 patch->old_name = patch->new_name = name;
214 if (!name)
215 die("unable to find filename in patch at line %d", linenr);
218 static int gitdiff_hdrend(const char *line, struct patch *patch)
220 return -1;
224 * We're anal about diff header consistency, to make
225 * sure that we don't end up having strange ambiguous
226 * patches floating around.
228 * As a result, gitdiff_{old|new}name() will check
229 * their names against any previous information, just
230 * to make sure..
232 static char *gitdiff_verify_name(const char *line, int isnull, char *orig_name, const char *oldnew)
234 int len;
235 const char *name;
237 if (!orig_name && !isnull)
238 return find_name(line, NULL, 1, 0);
240 name = "/dev/null";
241 len = 9;
242 if (orig_name) {
243 name = orig_name;
244 len = strlen(name);
245 if (isnull)
246 die("git-apply: bad git-diff - expected /dev/null, got %s on line %d", name, linenr);
249 if (*name == '/')
250 goto absolute_path;
252 for (;;) {
253 char c = *line++;
254 if (c == '\n')
255 break;
256 if (c != '/')
257 continue;
258 absolute_path:
259 if (memcmp(line, name, len) || line[len] != '\n')
260 break;
261 return orig_name;
263 die("git-apply: bad git-diff - inconsistent %s filename on line %d", oldnew, linenr);
264 return NULL;
267 static int gitdiff_oldname(const char *line, struct patch *patch)
269 patch->old_name = gitdiff_verify_name(line, patch->is_new, patch->old_name, "old");
270 return 0;
273 static int gitdiff_newname(const char *line, struct patch *patch)
275 patch->new_name = gitdiff_verify_name(line, patch->is_delete, patch->new_name, "new");
276 return 0;
279 static int gitdiff_oldmode(const char *line, struct patch *patch)
281 patch->old_mode = strtoul(line, NULL, 8);
282 return 0;
285 static int gitdiff_newmode(const char *line, struct patch *patch)
287 patch->new_mode = strtoul(line, NULL, 8);
288 return 0;
291 static int gitdiff_delete(const char *line, struct patch *patch)
293 patch->is_delete = 1;
294 patch->old_name = patch->def_name;
295 return gitdiff_oldmode(line, patch);
298 static int gitdiff_newfile(const char *line, struct patch *patch)
300 patch->is_new = 1;
301 patch->new_name = patch->def_name;
302 return gitdiff_newmode(line, patch);
305 static int gitdiff_copysrc(const char *line, struct patch *patch)
307 patch->is_copy = 1;
308 patch->old_name = find_name(line, NULL, 0, 0);
309 return 0;
312 static int gitdiff_copydst(const char *line, struct patch *patch)
314 patch->is_copy = 1;
315 patch->new_name = find_name(line, NULL, 0, 0);
316 return 0;
319 static int gitdiff_renamesrc(const char *line, struct patch *patch)
321 patch->is_rename = 1;
322 patch->old_name = find_name(line, NULL, 0, 0);
323 return 0;
326 static int gitdiff_renamedst(const char *line, struct patch *patch)
328 patch->is_rename = 1;
329 patch->new_name = find_name(line, NULL, 0, 0);
330 return 0;
333 static int gitdiff_similarity(const char *line, struct patch *patch)
335 if ((patch->score = strtoul(line, NULL, 10)) == ULONG_MAX)
336 patch->score = 0;
337 return 0;
340 static int gitdiff_dissimilarity(const char *line, struct patch *patch)
342 if ((patch->score = strtoul(line, NULL, 10)) == ULONG_MAX)
343 patch->score = 0;
344 return 0;
348 * This is normal for a diff that doesn't change anything: we'll fall through
349 * into the next diff. Tell the parser to break out.
351 static int gitdiff_unrecognized(const char *line, struct patch *patch)
353 return -1;
356 static char *git_header_name(char *line)
358 int len;
359 char *name, *second;
362 * Find the first '/'
364 name = line;
365 for (;;) {
366 char c = *name++;
367 if (c == '\n')
368 return NULL;
369 if (c == '/')
370 break;
374 * We don't accept absolute paths (/dev/null) as possibly valid
376 if (name == line+1)
377 return NULL;
380 * Accept a name only if it shows up twice, exactly the same
381 * form.
383 for (len = 0 ; ; len++) {
384 char c = name[len];
386 switch (c) {
387 default:
388 continue;
389 case '\n':
390 break;
391 case '\t': case ' ':
392 second = name+len;
393 for (;;) {
394 char c = *second++;
395 if (c == '\n')
396 return NULL;
397 if (c == '/')
398 break;
400 if (second[len] == '\n' && !memcmp(name, second, len)) {
401 char *ret = xmalloc(len + 1);
402 memcpy(ret, name, len);
403 ret[len] = 0;
404 return ret;
408 return NULL;
411 /* Verify that we recognize the lines following a git header */
412 static int parse_git_header(char *line, int len, unsigned int size, struct patch *patch)
414 unsigned long offset;
416 /* A git diff has explicit new/delete information, so we don't guess */
417 patch->is_new = 0;
418 patch->is_delete = 0;
421 * Some things may not have the old name in the
422 * rest of the headers anywhere (pure mode changes,
423 * or removing or adding empty files), so we get
424 * the default name from the header.
426 patch->def_name = git_header_name(line + strlen("diff --git "));
428 line += len;
429 size -= len;
430 linenr++;
431 for (offset = len ; size > 0 ; offset += len, size -= len, line += len, linenr++) {
432 static const struct opentry {
433 const char *str;
434 int (*fn)(const char *, struct patch *);
435 } optable[] = {
436 { "@@ -", gitdiff_hdrend },
437 { "--- ", gitdiff_oldname },
438 { "+++ ", gitdiff_newname },
439 { "old mode ", gitdiff_oldmode },
440 { "new mode ", gitdiff_newmode },
441 { "deleted file mode ", gitdiff_delete },
442 { "new file mode ", gitdiff_newfile },
443 { "copy from ", gitdiff_copysrc },
444 { "copy to ", gitdiff_copydst },
445 { "rename old ", gitdiff_renamesrc },
446 { "rename new ", gitdiff_renamedst },
447 { "rename from ", gitdiff_renamesrc },
448 { "rename to ", gitdiff_renamedst },
449 { "similarity index ", gitdiff_similarity },
450 { "dissimilarity index ", gitdiff_dissimilarity },
451 { "", gitdiff_unrecognized },
453 int i;
455 len = linelen(line, size);
456 if (!len || line[len-1] != '\n')
457 break;
458 for (i = 0; i < sizeof(optable) / sizeof(optable[0]); i++) {
459 const struct opentry *p = optable + i;
460 int oplen = strlen(p->str);
461 if (len < oplen || memcmp(p->str, line, oplen))
462 continue;
463 if (p->fn(line + oplen, patch) < 0)
464 return offset;
465 break;
469 return offset;
472 static int parse_num(const char *line, unsigned long *p)
474 char *ptr;
476 if (!isdigit(*line))
477 return 0;
478 *p = strtoul(line, &ptr, 10);
479 return ptr - line;
482 static int parse_range(const char *line, int len, int offset, const char *expect,
483 unsigned long *p1, unsigned long *p2)
485 int digits, ex;
487 if (offset < 0 || offset >= len)
488 return -1;
489 line += offset;
490 len -= offset;
492 digits = parse_num(line, p1);
493 if (!digits)
494 return -1;
496 offset += digits;
497 line += digits;
498 len -= digits;
500 *p2 = *p1;
501 if (*line == ',') {
502 digits = parse_num(line+1, p2);
503 if (!digits)
504 return -1;
506 offset += digits+1;
507 line += digits+1;
508 len -= digits+1;
511 ex = strlen(expect);
512 if (ex > len)
513 return -1;
514 if (memcmp(line, expect, ex))
515 return -1;
517 return offset + ex;
521 * Parse a unified diff fragment header of the
522 * form "@@ -a,b +c,d @@"
524 static int parse_fragment_header(char *line, int len, struct fragment *fragment)
526 int offset;
528 if (!len || line[len-1] != '\n')
529 return -1;
531 /* Figure out the number of lines in a fragment */
532 offset = parse_range(line, len, 4, " +", &fragment->oldpos, &fragment->oldlines);
533 offset = parse_range(line, len, offset, " @@", &fragment->newpos, &fragment->newlines);
535 return offset;
538 static int find_header(char *line, unsigned long size, int *hdrsize, struct patch *patch)
540 unsigned long offset, len;
542 patch->is_rename = patch->is_copy = 0;
543 patch->is_new = patch->is_delete = -1;
544 patch->old_mode = patch->new_mode = 0;
545 patch->old_name = patch->new_name = NULL;
546 for (offset = 0; size > 0; offset += len, size -= len, line += len, linenr++) {
547 unsigned long nextlen;
549 len = linelen(line, size);
550 if (!len)
551 break;
553 /* Testing this early allows us to take a few shortcuts.. */
554 if (len < 6)
555 continue;
558 * Make sure we don't find any unconnected patch fragmants.
559 * That's a sign that we didn't find a header, and that a
560 * patch has become corrupted/broken up.
562 if (!memcmp("@@ -", line, 4)) {
563 struct fragment dummy;
564 if (parse_fragment_header(line, len, &dummy) < 0)
565 continue;
566 error("patch fragment without header at line %d: %.*s", linenr, len-1, line);
569 if (size < len + 6)
570 break;
573 * Git patch? It might not have a real patch, just a rename
574 * or mode change, so we handle that specially
576 if (!memcmp("diff --git ", line, 11)) {
577 int git_hdr_len = parse_git_header(line, len, size, patch);
578 if (git_hdr_len <= len)
579 continue;
580 if (!patch->old_name && !patch->new_name) {
581 if (!patch->def_name)
582 die("git diff header lacks filename information (line %d)", linenr);
583 patch->old_name = patch->new_name = patch->def_name;
585 *hdrsize = git_hdr_len;
586 return offset;
589 /** --- followed by +++ ? */
590 if (memcmp("--- ", line, 4) || memcmp("+++ ", line + len, 4))
591 continue;
594 * We only accept unified patches, so we want it to
595 * at least have "@@ -a,b +c,d @@\n", which is 14 chars
596 * minimum
598 nextlen = linelen(line + len, size - len);
599 if (size < nextlen + 14 || memcmp("@@ -", line + len + nextlen, 4))
600 continue;
602 /* Ok, we'll consider it a patch */
603 parse_traditional_patch(line, line+len, patch);
604 *hdrsize = len + nextlen;
605 linenr += 2;
606 return offset;
608 return -1;
612 * Parse a unified diff. Note that this really needs
613 * to parse each fragment separately, since the only
614 * way to know the difference between a "---" that is
615 * part of a patch, and a "---" that starts the next
616 * patch is to look at the line counts..
618 static int parse_fragment(char *line, unsigned long size, struct patch *patch, struct fragment *fragment)
620 int added, deleted;
621 int len = linelen(line, size), offset;
622 unsigned long oldlines, newlines;
624 offset = parse_fragment_header(line, len, fragment);
625 if (offset < 0)
626 return -1;
627 oldlines = fragment->oldlines;
628 newlines = fragment->newlines;
630 if (patch->is_new < 0) {
631 patch->is_new = !oldlines;
632 if (!oldlines)
633 patch->old_name = NULL;
635 if (patch->is_delete < 0) {
636 patch->is_delete = !newlines;
637 if (!newlines)
638 patch->new_name = NULL;
641 if (patch->is_new != !oldlines)
642 return error("new file depends on old contents");
643 if (patch->is_delete != !newlines) {
644 if (newlines)
645 return error("deleted file still has contents");
646 fprintf(stderr, "** warning: file %s becomes empty but is not deleted\n", patch->new_name);
649 /* Parse the thing.. */
650 line += len;
651 size -= len;
652 linenr++;
653 added = deleted = 0;
654 for (offset = len; size > 0; offset += len, size -= len, line += len, linenr++) {
655 if (!oldlines && !newlines)
656 break;
657 len = linelen(line, size);
658 if (!len || line[len-1] != '\n')
659 return -1;
660 switch (*line) {
661 default:
662 return -1;
663 case ' ':
664 oldlines--;
665 newlines--;
666 break;
667 case '-':
668 deleted++;
669 oldlines--;
670 break;
671 case '+':
672 added++;
673 newlines--;
674 break;
675 /* We allow "\ No newline at end of file" */
676 case '\\':
677 if (len < 12 || memcmp(line, "\\ No newline", 12))
678 return -1;
679 break;
682 /* If a fragment ends with an incomplete line, we failed to include
683 * it in the above loop because we hit oldlines == newlines == 0
684 * before seeing it.
686 if (12 < size && !memcmp(line, "\\ No newline", 12))
687 offset += linelen(line, size);
689 patch->lines_added += added;
690 patch->lines_deleted += deleted;
691 return offset;
694 static int parse_single_patch(char *line, unsigned long size, struct patch *patch)
696 unsigned long offset = 0;
697 struct fragment **fragp = &patch->fragments;
699 while (size > 4 && !memcmp(line, "@@ -", 4)) {
700 struct fragment *fragment;
701 int len;
703 fragment = xmalloc(sizeof(*fragment));
704 memset(fragment, 0, sizeof(*fragment));
705 len = parse_fragment(line, size, patch, fragment);
706 if (len <= 0)
707 die("corrupt patch at line %d", linenr);
709 fragment->patch = line;
710 fragment->size = len;
712 *fragp = fragment;
713 fragp = &fragment->next;
715 offset += len;
716 line += len;
717 size -= len;
719 return offset;
722 static int parse_chunk(char *buffer, unsigned long size, struct patch *patch)
724 int hdrsize, patchsize;
725 int offset = find_header(buffer, size, &hdrsize, patch);
727 if (offset < 0)
728 return offset;
730 patchsize = parse_single_patch(buffer + offset + hdrsize, size - offset - hdrsize, patch);
732 return offset + hdrsize + patchsize;
735 static const char pluses[] = "++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++";
736 static const char minuses[]= "----------------------------------------------------------------------";
738 static void show_stats(struct patch *patch)
740 const char *prefix = "";
741 char *name = patch->new_name;
742 int len, max, add, del, total;
744 if (!name)
745 name = patch->old_name;
748 * "scale" the filename
750 len = strlen(name);
751 max = max_len;
752 if (max > 50)
753 max = 50;
754 if (len > max) {
755 char *slash;
756 prefix = "...";
757 max -= 3;
758 name += len - max;
759 slash = strchr(name, '/');
760 if (slash)
761 name = slash;
763 len = max;
766 * scale the add/delete
768 max = max_change;
769 if (max + len > 70)
770 max = 70 - len;
772 add = patch->lines_added;
773 del = patch->lines_deleted;
774 total = add + del;
776 if (max_change > 0) {
777 total = (total * max + max_change / 2) / max_change;
778 add = (add * max + max_change / 2) / max_change;
779 del = total - add;
781 printf(" %s%-*s |%5d %.*s%.*s\n", prefix,
782 len, name, patch->lines_added + patch->lines_deleted,
783 add, pluses, del, minuses);
786 static int read_old_data(struct stat *st, const char *path, void *buf, unsigned long size)
788 int fd;
789 unsigned long got;
791 switch (st->st_mode & S_IFMT) {
792 case S_IFLNK:
793 return readlink(path, buf, size);
794 case S_IFREG:
795 fd = open(path, O_RDONLY);
796 if (fd < 0)
797 return error("unable to open %s", path);
798 got = 0;
799 for (;;) {
800 int ret = read(fd, buf + got, size - got);
801 if (ret < 0) {
802 if (errno == EAGAIN)
803 continue;
804 break;
806 if (!ret)
807 break;
808 got += ret;
810 close(fd);
811 return got;
813 default:
814 return -1;
818 static int find_offset(const char *buf, unsigned long size, const char *fragment, unsigned long fragsize, int line)
820 int i;
821 unsigned long start, backwards, forwards;
823 if (fragsize > size)
824 return -1;
826 start = 0;
827 if (line > 1) {
828 unsigned long offset = 0;
829 i = line-1;
830 while (offset + fragsize <= size) {
831 if (buf[offset++] == '\n') {
832 start = offset;
833 if (!--i)
834 break;
839 /* Exact line number? */
840 if (!memcmp(buf + start, fragment, fragsize))
841 return start;
844 * There's probably some smart way to do this, but I'll leave
845 * that to the smart and beautiful people. I'm simple and stupid.
847 backwards = start;
848 forwards = start;
849 for (i = 0; ; i++) {
850 unsigned long try;
851 int n;
853 /* "backward" */
854 if (i & 1) {
855 if (!backwards) {
856 if (forwards + fragsize > size)
857 break;
858 continue;
860 do {
861 --backwards;
862 } while (backwards && buf[backwards-1] != '\n');
863 try = backwards;
864 } else {
865 while (forwards + fragsize <= size) {
866 if (buf[forwards++] == '\n')
867 break;
869 try = forwards;
872 if (try + fragsize > size)
873 continue;
874 if (memcmp(buf + try, fragment, fragsize))
875 continue;
876 n = (i >> 1)+1;
877 if (i & 1)
878 n = -n;
879 return try;
883 * We should start searching forward and backward.
885 return -1;
888 struct buffer_desc {
889 char *buffer;
890 unsigned long size;
891 unsigned long alloc;
894 static int apply_one_fragment(struct buffer_desc *desc, struct fragment *frag)
896 char *buf = desc->buffer;
897 const char *patch = frag->patch;
898 int offset, size = frag->size;
899 char *old = xmalloc(size);
900 char *new = xmalloc(size);
901 int oldsize = 0, newsize = 0;
903 while (size > 0) {
904 int len = linelen(patch, size);
905 int plen;
907 if (!len)
908 break;
911 * "plen" is how much of the line we should use for
912 * the actual patch data. Normally we just remove the
913 * first character on the line, but if the line is
914 * followed by "\ No newline", then we also remove the
915 * last one (which is the newline, of course).
917 plen = len-1;
918 if (len < size && patch[len] == '\\')
919 plen--;
920 switch (*patch) {
921 case ' ':
922 case '-':
923 memcpy(old + oldsize, patch + 1, plen);
924 oldsize += plen;
925 if (*patch == '-')
926 break;
927 /* Fall-through for ' ' */
928 case '+':
929 memcpy(new + newsize, patch + 1, plen);
930 newsize += plen;
931 break;
932 case '@': case '\\':
933 /* Ignore it, we already handled it */
934 break;
935 default:
936 return -1;
938 patch += len;
939 size -= len;
942 offset = find_offset(buf, desc->size, old, oldsize, frag->newpos);
943 if (offset >= 0) {
944 int diff = newsize - oldsize;
945 unsigned long size = desc->size + diff;
946 unsigned long alloc = desc->alloc;
948 if (size > alloc) {
949 alloc = size + 8192;
950 desc->alloc = alloc;
951 buf = xrealloc(buf, alloc);
952 desc->buffer = buf;
954 desc->size = size;
955 memmove(buf + offset + newsize, buf + offset + oldsize, size - offset - newsize);
956 memcpy(buf + offset, new, newsize);
957 offset = 0;
960 free(old);
961 free(new);
962 return offset;
965 static int apply_fragments(struct buffer_desc *desc, struct patch *patch)
967 struct fragment *frag = patch->fragments;
969 while (frag) {
970 if (apply_one_fragment(desc, frag) < 0)
971 return error("patch failed: %s:%d", patch->old_name, frag->oldpos);
972 frag = frag->next;
974 return 0;
977 static int apply_data(struct patch *patch, struct stat *st)
979 char *buf;
980 unsigned long size, alloc;
981 struct buffer_desc desc;
983 size = 0;
984 alloc = 0;
985 buf = NULL;
986 if (patch->old_name) {
987 size = st->st_size;
988 alloc = size + 8192;
989 buf = xmalloc(alloc);
990 if (read_old_data(st, patch->old_name, buf, alloc) != size)
991 return error("read of %s failed", patch->old_name);
994 desc.size = size;
995 desc.alloc = alloc;
996 desc.buffer = buf;
997 if (apply_fragments(&desc, patch) < 0)
998 return -1;
999 patch->result = desc.buffer;
1000 patch->resultsize = desc.size;
1002 if (patch->is_delete && patch->resultsize)
1003 return error("removal patch leaves file contents");
1005 return 0;
1008 static int check_patch(struct patch *patch)
1010 struct stat st;
1011 const char *old_name = patch->old_name;
1012 const char *new_name = patch->new_name;
1014 if (old_name) {
1015 int changed;
1017 if (lstat(old_name, &st) < 0)
1018 return error("%s: %s", old_name, strerror(errno));
1019 if (check_index) {
1020 int pos = cache_name_pos(old_name, strlen(old_name));
1021 if (pos < 0)
1022 return error("%s: does not exist in index", old_name);
1023 changed = ce_match_stat(active_cache[pos], &st);
1024 if (changed)
1025 return error("%s: does not match index", old_name);
1027 if (patch->is_new < 0)
1028 patch->is_new = 0;
1029 st.st_mode = ntohl(create_ce_mode(st.st_mode));
1030 if (!patch->old_mode)
1031 patch->old_mode = st.st_mode;
1032 if ((st.st_mode ^ patch->old_mode) & S_IFMT)
1033 return error("%s: wrong type", old_name);
1034 if (st.st_mode != patch->old_mode)
1035 fprintf(stderr, "warning: %s has type %o, expected %o\n",
1036 old_name, st.st_mode, patch->old_mode);
1039 if (new_name && (patch->is_new | patch->is_rename | patch->is_copy)) {
1040 if (check_index && cache_name_pos(new_name, strlen(new_name)) >= 0)
1041 return error("%s: already exists in index", new_name);
1042 if (!lstat(new_name, &st))
1043 return error("%s: already exists in working directory", new_name);
1044 if (errno != ENOENT)
1045 return error("%s: %s", new_name, strerror(errno));
1046 if (!patch->new_mode)
1047 patch->new_mode = S_IFREG | 0644;
1050 if (new_name && old_name) {
1051 int same = !strcmp(old_name, new_name);
1052 if (!patch->new_mode)
1053 patch->new_mode = patch->old_mode;
1054 if ((patch->old_mode ^ patch->new_mode) & S_IFMT)
1055 return error("new mode (%o) of %s does not match old mode (%o)%s%s",
1056 patch->new_mode, new_name, patch->old_mode,
1057 same ? "" : " of ", same ? "" : old_name);
1060 if (apply_data(patch, &st) < 0)
1061 return error("%s: patch does not apply", old_name);
1062 return 0;
1065 static int check_patch_list(struct patch *patch)
1067 int error = 0;
1069 for (;patch ; patch = patch->next)
1070 error |= check_patch(patch);
1071 return error;
1074 static void show_file(int c, unsigned int mode, const char *name)
1076 printf("%c %o %s\n", c, mode, name);
1079 static void show_file_list(struct patch *patch)
1081 for (;patch ; patch = patch->next) {
1082 if (patch->is_rename) {
1083 show_file('-', patch->old_mode, patch->old_name);
1084 show_file('+', patch->new_mode, patch->new_name);
1085 continue;
1087 if (patch->is_copy || patch->is_new) {
1088 show_file('+', patch->new_mode, patch->new_name);
1089 continue;
1091 if (patch->is_delete) {
1092 show_file('-', patch->old_mode, patch->old_name);
1093 continue;
1095 if (patch->old_mode && patch->new_mode && patch->old_mode != patch->new_mode) {
1096 printf("M %o:%o %s\n", patch->old_mode, patch->new_mode, patch->old_name);
1097 continue;
1099 printf("M %o %s\n", patch->old_mode, patch->old_name);
1103 static void stat_patch_list(struct patch *patch)
1105 int files, adds, dels;
1107 for (files = adds = dels = 0 ; patch ; patch = patch->next) {
1108 files++;
1109 adds += patch->lines_added;
1110 dels += patch->lines_deleted;
1111 show_stats(patch);
1114 printf(" %d files changed, %d insertions(+), %d deletions(-)\n", files, adds, dels);
1117 static void show_file_mode_name(const char *newdelete, unsigned int mode, const char *name)
1119 if (mode)
1120 printf(" %s mode %06o %s\n", newdelete, mode, name);
1121 else
1122 printf(" %s %s\n", newdelete, name);
1125 static void show_mode_change(struct patch *p, int show_name)
1127 if (p->old_mode && p->new_mode && p->old_mode != p->new_mode) {
1128 if (show_name)
1129 printf(" mode change %06o => %06o %s\n",
1130 p->old_mode, p->new_mode, p->new_name);
1131 else
1132 printf(" mode change %06o => %06o\n",
1133 p->old_mode, p->new_mode);
1137 static void show_rename_copy(struct patch *p)
1139 const char *renamecopy = p->is_rename ? "rename" : "copy";
1140 const char *old, *new;
1142 /* Find common prefix */
1143 old = p->old_name;
1144 new = p->new_name;
1145 while (1) {
1146 const char *slash_old, *slash_new;
1147 slash_old = strchr(old, '/');
1148 slash_new = strchr(new, '/');
1149 if (!slash_old ||
1150 !slash_new ||
1151 slash_old - old != slash_new - new ||
1152 memcmp(old, new, slash_new - new))
1153 break;
1154 old = slash_old + 1;
1155 new = slash_new + 1;
1157 /* p->old_name thru old is the common prefix, and old and new
1158 * through the end of names are renames
1160 if (old != p->old_name)
1161 printf(" %s %.*s{%s => %s} (%d%%)\n", renamecopy,
1162 (int)(old - p->old_name), p->old_name,
1163 old, new, p->score);
1164 else
1165 printf(" %s %s => %s (%d%%)\n", renamecopy,
1166 p->old_name, p->new_name, p->score);
1167 show_mode_change(p, 0);
1170 static void summary_patch_list(struct patch *patch)
1172 struct patch *p;
1174 for (p = patch; p; p = p->next) {
1175 if (p->is_new)
1176 show_file_mode_name("create", p->new_mode, p->new_name);
1177 else if (p->is_delete)
1178 show_file_mode_name("delete", p->old_mode, p->old_name);
1179 else {
1180 if (p->is_rename || p->is_copy)
1181 show_rename_copy(p);
1182 else {
1183 if (p->score) {
1184 printf(" rewrite %s (%d%%)\n",
1185 p->new_name, p->score);
1186 show_mode_change(p, 0);
1188 else
1189 show_mode_change(p, 1);
1195 static void patch_stats(struct patch *patch)
1197 int lines = patch->lines_added + patch->lines_deleted;
1199 if (lines > max_change)
1200 max_change = lines;
1201 if (patch->old_name) {
1202 int len = strlen(patch->old_name);
1203 if (len > max_len)
1204 max_len = len;
1206 if (patch->new_name) {
1207 int len = strlen(patch->new_name);
1208 if (len > max_len)
1209 max_len = len;
1213 static void remove_file(struct patch *patch)
1215 if (write_index) {
1216 if (remove_file_from_cache(patch->old_name) < 0)
1217 die("unable to remove %s from index", patch->old_name);
1219 unlink(patch->old_name);
1222 static void add_index_file(const char *path, unsigned mode, void *buf, unsigned long size)
1224 struct stat st;
1225 struct cache_entry *ce;
1226 int namelen = strlen(path);
1227 unsigned ce_size = cache_entry_size(namelen);
1229 if (!write_index)
1230 return;
1232 ce = xmalloc(ce_size);
1233 memset(ce, 0, ce_size);
1234 memcpy(ce->name, path, namelen);
1235 ce->ce_mode = create_ce_mode(mode);
1236 ce->ce_flags = htons(namelen);
1237 if (lstat(path, &st) < 0)
1238 die("unable to stat newly created file %s", path);
1239 fill_stat_cache_info(ce, &st);
1240 if (write_sha1_file(buf, size, "blob", ce->sha1) < 0)
1241 die("unable to create backing store for newly created file %s", path);
1242 if (add_cache_entry(ce, ADD_CACHE_OK_TO_ADD) < 0)
1243 die("unable to add cache entry for %s", path);
1246 static void create_subdirectories(const char *path)
1248 int len = strlen(path);
1249 char *buf = xmalloc(len + 1);
1250 const char *slash = path;
1252 while ((slash = strchr(slash+1, '/')) != NULL) {
1253 len = slash - path;
1254 memcpy(buf, path, len);
1255 buf[len] = 0;
1256 if (mkdir(buf, 0777) < 0) {
1257 if (errno != EEXIST)
1258 break;
1261 free(buf);
1264 static int try_create_file(const char *path, unsigned int mode, const char *buf, unsigned long size)
1266 int fd;
1268 if (S_ISLNK(mode))
1269 return symlink(buf, path);
1270 fd = open(path, O_CREAT | O_EXCL | O_WRONLY | O_TRUNC, (mode & 0100) ? 0777 : 0666);
1271 if (fd < 0)
1272 return -1;
1273 while (size) {
1274 int written = write(fd, buf, size);
1275 if (written < 0) {
1276 if (errno == EINTR || errno == EAGAIN)
1277 continue;
1278 die("writing file %s: %s", path, strerror(errno));
1280 if (!written)
1281 die("out of space writing file %s", path);
1282 buf += written;
1283 size -= written;
1285 if (close(fd) < 0)
1286 die("closing file %s: %s", path, strerror(errno));
1287 return 0;
1291 * We optimistically assume that the directories exist,
1292 * which is true 99% of the time anyway. If they don't,
1293 * we create them and try again.
1295 static void create_one_file(const char *path, unsigned mode, const char *buf, unsigned long size)
1297 if (!try_create_file(path, mode, buf, size))
1298 return;
1300 if (errno == ENOENT) {
1301 create_subdirectories(path);
1302 if (!try_create_file(path, mode, buf, size))
1303 return;
1306 if (errno == EEXIST) {
1307 unsigned int nr = getpid();
1309 for (;;) {
1310 const char *newpath;
1311 newpath = mkpath("%s~%u", path, nr);
1312 if (!try_create_file(newpath, mode, buf, size)) {
1313 if (!rename(newpath, path))
1314 return;
1315 unlink(newpath);
1316 break;
1318 if (errno != EEXIST)
1319 break;
1322 die("unable to write file %s mode %o", path, mode);
1325 static void create_file(struct patch *patch)
1327 const char *path = patch->new_name;
1328 unsigned mode = patch->new_mode;
1329 unsigned long size = patch->resultsize;
1330 char *buf = patch->result;
1332 if (!mode)
1333 mode = S_IFREG | 0644;
1334 create_one_file(path, mode, buf, size);
1335 add_index_file(path, mode, buf, size);
1338 static void write_out_one_result(struct patch *patch)
1340 if (patch->is_delete > 0) {
1341 remove_file(patch);
1342 return;
1344 if (patch->is_new > 0 || patch->is_copy) {
1345 create_file(patch);
1346 return;
1349 * Rename or modification boils down to the same
1350 * thing: remove the old, write the new
1352 remove_file(patch);
1353 create_file(patch);
1356 static void write_out_results(struct patch *list, int skipped_patch)
1358 if (!list && !skipped_patch)
1359 die("No changes");
1361 while (list) {
1362 write_out_one_result(list);
1363 list = list->next;
1367 static struct cache_file cache_file;
1369 static struct excludes {
1370 struct excludes *next;
1371 const char *path;
1372 } *excludes;
1374 static int use_patch(struct patch *p)
1376 const char *pathname = p->new_name ? : p->old_name;
1377 struct excludes *x = excludes;
1378 while (x) {
1379 if (fnmatch(x->path, pathname, 0) == 0)
1380 return 0;
1381 x = x->next;
1383 return 1;
1386 static int apply_patch(int fd)
1388 int newfd;
1389 unsigned long offset, size;
1390 char *buffer = read_patch_file(fd, &size);
1391 struct patch *list = NULL, **listp = &list;
1392 int skipped_patch = 0;
1394 if (!buffer)
1395 return -1;
1396 offset = 0;
1397 while (size > 0) {
1398 struct patch *patch;
1399 int nr;
1401 patch = xmalloc(sizeof(*patch));
1402 memset(patch, 0, sizeof(*patch));
1403 nr = parse_chunk(buffer + offset, size, patch);
1404 if (nr < 0)
1405 break;
1406 if (use_patch(patch)) {
1407 patch_stats(patch);
1408 *listp = patch;
1409 listp = &patch->next;
1410 } else {
1411 /* perhaps free it a bit better? */
1412 free(patch);
1413 skipped_patch++;
1415 offset += nr;
1416 size -= nr;
1419 newfd = -1;
1420 write_index = check_index && apply;
1421 if (write_index)
1422 newfd = hold_index_file_for_update(&cache_file, get_index_file());
1423 if (check_index) {
1424 if (read_cache() < 0)
1425 die("unable to read index file");
1428 if ((check || apply) && check_patch_list(list) < 0)
1429 exit(1);
1431 if (apply)
1432 write_out_results(list, skipped_patch);
1434 if (write_index) {
1435 if (write_cache(newfd, active_cache, active_nr) ||
1436 commit_index_file(&cache_file))
1437 die("Unable to write new cachefile");
1440 if (show_files)
1441 show_file_list(list);
1443 if (diffstat)
1444 stat_patch_list(list);
1446 if (summary)
1447 summary_patch_list(list);
1449 free(buffer);
1450 return 0;
1453 int main(int argc, char **argv)
1455 int i;
1456 int read_stdin = 1;
1458 for (i = 1; i < argc; i++) {
1459 const char *arg = argv[i];
1460 int fd;
1462 if (!strcmp(arg, "-")) {
1463 apply_patch(0);
1464 read_stdin = 0;
1465 continue;
1467 if (!strncmp(arg, "--exclude=", 10)) {
1468 struct excludes *x = xmalloc(sizeof(*x));
1469 x->path = arg + 10;
1470 x->next = excludes;
1471 excludes = x;
1472 continue;
1474 /* NEEDSWORK: this does not do anything at this moment. */
1475 if (!strcmp(arg, "--no-merge")) {
1476 merge_patch = 0;
1477 continue;
1479 if (!strcmp(arg, "--stat")) {
1480 apply = 0;
1481 diffstat = 1;
1482 continue;
1484 if (!strcmp(arg, "--summary")) {
1485 apply = 0;
1486 summary = 1;
1487 continue;
1489 if (!strcmp(arg, "--check")) {
1490 apply = 0;
1491 check = 1;
1492 continue;
1494 if (!strcmp(arg, "--index")) {
1495 check_index = 1;
1496 continue;
1498 if (!strcmp(arg, "--apply")) {
1499 apply = 1;
1500 continue;
1502 if (!strcmp(arg, "--show-files")) {
1503 show_files = 1;
1504 continue;
1506 fd = open(arg, O_RDONLY);
1507 if (fd < 0)
1508 usage(apply_usage);
1509 read_stdin = 0;
1510 apply_patch(fd);
1511 close(fd);
1513 if (read_stdin)
1514 apply_patch(0);
1515 return 0;