Allow hierarchical section names
[git] / apply.c
1 /*
2  * apply.c
3  *
4  * Copyright (C) Linus Torvalds, 2005
5  *
6  * This applies patches on top of some (arbitrary) version of the SCM.
7  *
8  */
9 #include <fnmatch.h>
10 #include "cache.h"
11 #include "quote.h"
12
13 //  --check turns on checking that the working tree matches the
14 //    files that are being modified, but doesn't apply the patch
15 //  --stat does just a diffstat, and doesn't actually apply
16 //  --numstat does numeric diffstat, and doesn't actually apply
17 //  --index-info shows the old and new index info for paths if available.
18 //
19 static int allow_binary_replacement = 0;
20 static int check_index = 0;
21 static int write_index = 0;
22 static int diffstat = 0;
23 static int numstat = 0;
24 static int summary = 0;
25 static int check = 0;
26 static int apply = 1;
27 static int no_add = 0;
28 static int show_index_info = 0;
29 static int line_termination = '\n';
30 static const char apply_usage[] =
31 "git-apply [--stat] [--numstat] [--summary] [--check] [--index] [--apply] [--no-add] [--index-info] [--allow-binary-replacement] [-z] <patch>...";
32
33 /*
34  * For "diff-stat" like behaviour, we keep track of the biggest change
35  * we've seen, and the longest filename. That allows us to do simple
36  * scaling.
37  */
38 static int max_change, max_len;
39
40 /*
41  * Various "current state", notably line numbers and what
42  * file (and how) we're patching right now.. The "is_xxxx"
43  * things are flags, where -1 means "don't know yet".
44  */
45 static int linenr = 1;
46
47 struct fragment {
48         unsigned long oldpos, oldlines;
49         unsigned long newpos, newlines;
50         const char *patch;
51         int size;
52         struct fragment *next;
53 };
54
55 struct patch {
56         char *new_name, *old_name, *def_name;
57         unsigned int old_mode, new_mode;
58         int is_rename, is_copy, is_new, is_delete, is_binary;
59         int lines_added, lines_deleted;
60         int score;
61         struct fragment *fragments;
62         char *result;
63         unsigned long resultsize;
64         char old_sha1_prefix[41];
65         char new_sha1_prefix[41];
66         struct patch *next;
67 };
68
69 #define CHUNKSIZE (8192)
70 #define SLOP (16)
71
72 static void *read_patch_file(int fd, unsigned long *sizep)
73 {
74         unsigned long size = 0, alloc = CHUNKSIZE;
75         void *buffer = xmalloc(alloc);
76
77         for (;;) {
78                 int nr = alloc - size;
79                 if (nr < 1024) {
80                         alloc += CHUNKSIZE;
81                         buffer = xrealloc(buffer, alloc);
82                         nr = alloc - size;
83                 }
84                 nr = read(fd, buffer + size, nr);
85                 if (!nr)
86                         break;
87                 if (nr < 0) {
88                         if (errno == EAGAIN)
89                                 continue;
90                         die("git-apply: read returned %s", strerror(errno));
91                 }
92                 size += nr;
93         }
94         *sizep = size;
95
96         /*
97          * Make sure that we have some slop in the buffer
98          * so that we can do speculative "memcmp" etc, and
99          * see to it that it is NUL-filled.
100          */
101         if (alloc < size + SLOP)
102                 buffer = xrealloc(buffer, size + SLOP);
103         memset(buffer + size, 0, SLOP);
104         return buffer;
105 }
106
107 static unsigned long linelen(const char *buffer, unsigned long size)
108 {
109         unsigned long len = 0;
110         while (size--) {
111                 len++;
112                 if (*buffer++ == '\n')
113                         break;
114         }
115         return len;
116 }
117
118 static int is_dev_null(const char *str)
119 {
120         return !memcmp("/dev/null", str, 9) && isspace(str[9]);
121 }
122
123 #define TERM_SPACE      1
124 #define TERM_TAB        2
125
126 static int name_terminate(const char *name, int namelen, int c, int terminate)
127 {
128         if (c == ' ' && !(terminate & TERM_SPACE))
129                 return 0;
130         if (c == '\t' && !(terminate & TERM_TAB))
131                 return 0;
132
133         return 1;
134 }
135
136 static char * find_name(const char *line, char *def, int p_value, int terminate)
137 {
138         int len;
139         const char *start = line;
140         char *name;
141
142         if (*line == '"') {
143                 /* Proposed "new-style" GNU patch/diff format; see
144                  * http://marc.theaimsgroup.com/?l=git&m=112927316408690&w=2
145                  */
146                 name = unquote_c_style(line, NULL);
147                 if (name) {
148                         char *cp = name;
149                         while (p_value) {
150                                 cp = strchr(name, '/');
151                                 if (!cp)
152                                         break;
153                                 cp++;
154                                 p_value--;
155                         }
156                         if (cp) {
157                                 /* name can later be freed, so we need
158                                  * to memmove, not just return cp
159                                  */
160                                 memmove(name, cp, strlen(cp) + 1);
161                                 free(def);
162                                 return name;
163                         }
164                         else {
165                                 free(name);
166                                 name = NULL;
167                         }
168                 }
169         }
170
171         for (;;) {
172                 char c = *line;
173
174                 if (isspace(c)) {
175                         if (c == '\n')
176                                 break;
177                         if (name_terminate(start, line-start, c, terminate))
178                                 break;
179                 }
180                 line++;
181                 if (c == '/' && !--p_value)
182                         start = line;
183         }
184         if (!start)
185                 return def;
186         len = line - start;
187         if (!len)
188                 return def;
189
190         /*
191          * Generally we prefer the shorter name, especially
192          * if the other one is just a variation of that with
193          * something else tacked on to the end (ie "file.orig"
194          * or "file~").
195          */
196         if (def) {
197                 int deflen = strlen(def);
198                 if (deflen < len && !strncmp(start, def, deflen))
199                         return def;
200         }
201
202         name = xmalloc(len + 1);
203         memcpy(name, start, len);
204         name[len] = 0;
205         free(def);
206         return name;
207 }
208
209 /*
210  * Get the name etc info from the --/+++ lines of a traditional patch header
211  *
212  * NOTE! This hardcodes "-p1" behaviour in filename detection.
213  *
214  * FIXME! The end-of-filename heuristics are kind of screwy. For existing
215  * files, we can happily check the index for a match, but for creating a
216  * new file we should try to match whatever "patch" does. I have no idea.
217  */
218 static void parse_traditional_patch(const char *first, const char *second, struct patch *patch)
219 {
220         int p_value = 1;
221         char *name;
222
223         first += 4;     // skip "--- "
224         second += 4;    // skip "+++ "
225         if (is_dev_null(first)) {
226                 patch->is_new = 1;
227                 patch->is_delete = 0;
228                 name = find_name(second, NULL, p_value, TERM_SPACE | TERM_TAB);
229                 patch->new_name = name;
230         } else if (is_dev_null(second)) {
231                 patch->is_new = 0;
232                 patch->is_delete = 1;
233                 name = find_name(first, NULL, p_value, TERM_SPACE | TERM_TAB);
234                 patch->old_name = name;
235         } else {
236                 name = find_name(first, NULL, p_value, TERM_SPACE | TERM_TAB);
237                 name = find_name(second, name, p_value, TERM_SPACE | TERM_TAB);
238                 patch->old_name = patch->new_name = name;
239         }
240         if (!name)
241                 die("unable to find filename in patch at line %d", linenr);
242 }
243
244 static int gitdiff_hdrend(const char *line, struct patch *patch)
245 {
246         return -1;
247 }
248
249 /*
250  * We're anal about diff header consistency, to make
251  * sure that we don't end up having strange ambiguous
252  * patches floating around.
253  *
254  * As a result, gitdiff_{old|new}name() will check
255  * their names against any previous information, just
256  * to make sure..
257  */
258 static char *gitdiff_verify_name(const char *line, int isnull, char *orig_name, const char *oldnew)
259 {
260         if (!orig_name && !isnull)
261                 return find_name(line, NULL, 1, 0);
262
263         if (orig_name) {
264                 int len;
265                 const char *name;
266                 char *another;
267                 name = orig_name;
268                 len = strlen(name);
269                 if (isnull)
270                         die("git-apply: bad git-diff - expected /dev/null, got %s on line %d", name, linenr);
271                 another = find_name(line, NULL, 1, 0);
272                 if (!another || memcmp(another, name, len))
273                         die("git-apply: bad git-diff - inconsistent %s filename on line %d", oldnew, linenr);
274                 free(another);
275                 return orig_name;
276         }
277         else {
278                 /* expect "/dev/null" */
279                 if (memcmp("/dev/null", line, 9) || line[9] != '\n')
280                         die("git-apply: bad git-diff - expected /dev/null on line %d", linenr);
281                 return NULL;
282         }
283 }
284
285 static int gitdiff_oldname(const char *line, struct patch *patch)
286 {
287         patch->old_name = gitdiff_verify_name(line, patch->is_new, patch->old_name, "old");
288         return 0;
289 }
290
291 static int gitdiff_newname(const char *line, struct patch *patch)
292 {
293         patch->new_name = gitdiff_verify_name(line, patch->is_delete, patch->new_name, "new");
294         return 0;
295 }
296
297 static int gitdiff_oldmode(const char *line, struct patch *patch)
298 {
299         patch->old_mode = strtoul(line, NULL, 8);
300         return 0;
301 }
302
303 static int gitdiff_newmode(const char *line, struct patch *patch)
304 {
305         patch->new_mode = strtoul(line, NULL, 8);
306         return 0;
307 }
308
309 static int gitdiff_delete(const char *line, struct patch *patch)
310 {
311         patch->is_delete = 1;
312         patch->old_name = patch->def_name;
313         return gitdiff_oldmode(line, patch);
314 }
315
316 static int gitdiff_newfile(const char *line, struct patch *patch)
317 {
318         patch->is_new = 1;
319         patch->new_name = patch->def_name;
320         return gitdiff_newmode(line, patch);
321 }
322
323 static int gitdiff_copysrc(const char *line, struct patch *patch)
324 {
325         patch->is_copy = 1;
326         patch->old_name = find_name(line, NULL, 0, 0);
327         return 0;
328 }
329
330 static int gitdiff_copydst(const char *line, struct patch *patch)
331 {
332         patch->is_copy = 1;
333         patch->new_name = find_name(line, NULL, 0, 0);
334         return 0;
335 }
336
337 static int gitdiff_renamesrc(const char *line, struct patch *patch)
338 {
339         patch->is_rename = 1;
340         patch->old_name = find_name(line, NULL, 0, 0);
341         return 0;
342 }
343
344 static int gitdiff_renamedst(const char *line, struct patch *patch)
345 {
346         patch->is_rename = 1;
347         patch->new_name = find_name(line, NULL, 0, 0);
348         return 0;
349 }
350
351 static int gitdiff_similarity(const char *line, struct patch *patch)
352 {
353         if ((patch->score = strtoul(line, NULL, 10)) == ULONG_MAX)
354                 patch->score = 0;
355         return 0;
356 }
357
358 static int gitdiff_dissimilarity(const char *line, struct patch *patch)
359 {
360         if ((patch->score = strtoul(line, NULL, 10)) == ULONG_MAX)
361                 patch->score = 0;
362         return 0;
363 }
364
365 static int gitdiff_index(const char *line, struct patch *patch)
366 {
367         /* index line is N hexadecimal, "..", N hexadecimal,
368          * and optional space with octal mode.
369          */
370         const char *ptr, *eol;
371         int len;
372
373         ptr = strchr(line, '.');
374         if (!ptr || ptr[1] != '.' || 40 < ptr - line)
375                 return 0;
376         len = ptr - line;
377         memcpy(patch->old_sha1_prefix, line, len);
378         patch->old_sha1_prefix[len] = 0;
379
380         line = ptr + 2;
381         ptr = strchr(line, ' ');
382         eol = strchr(line, '\n');
383
384         if (!ptr || eol < ptr)
385                 ptr = eol;
386         len = ptr - line;
387
388         if (40 < len)
389                 return 0;
390         memcpy(patch->new_sha1_prefix, line, len);
391         patch->new_sha1_prefix[len] = 0;
392         if (*ptr == ' ')
393                 patch->new_mode = patch->old_mode = strtoul(ptr+1, NULL, 8);
394         return 0;
395 }
396
397 /*
398  * This is normal for a diff that doesn't change anything: we'll fall through
399  * into the next diff. Tell the parser to break out.
400  */
401 static int gitdiff_unrecognized(const char *line, struct patch *patch)
402 {
403         return -1;
404 }
405
406 static const char *stop_at_slash(const char *line, int llen)
407 {
408         int i;
409
410         for (i = 0; i < llen; i++) {
411                 int ch = line[i];
412                 if (ch == '/')
413                         return line + i;
414         }
415         return NULL;
416 }
417
418 /* This is to extract the same name that appears on "diff --git"
419  * line.  We do not find and return anything if it is a rename
420  * patch, and it is OK because we will find the name elsewhere.
421  * We need to reliably find name only when it is mode-change only,
422  * creation or deletion of an empty file.  In any of these cases,
423  * both sides are the same name under a/ and b/ respectively.
424  */
425 static char *git_header_name(char *line, int llen)
426 {
427         int len;
428         const char *name;
429         const char *second = NULL;
430
431         line += strlen("diff --git ");
432         llen -= strlen("diff --git ");
433
434         if (*line == '"') {
435                 const char *cp;
436                 char *first = unquote_c_style(line, &second);
437                 if (!first)
438                         return NULL;
439
440                 /* advance to the first slash */
441                 cp = stop_at_slash(first, strlen(first));
442                 if (!cp || cp == first) {
443                         /* we do not accept absolute paths */
444                 free_first_and_fail:
445                         free(first);
446                         return NULL;
447                 }
448                 len = strlen(cp+1);
449                 memmove(first, cp+1, len+1); /* including NUL */
450
451                 /* second points at one past closing dq of name.
452                  * find the second name.
453                  */
454                 while ((second < line + llen) && isspace(*second))
455                         second++;
456
457                 if (line + llen <= second)
458                         goto free_first_and_fail;
459                 if (*second == '"') {
460                         char *sp = unquote_c_style(second, NULL);
461                         if (!sp)
462                                 goto free_first_and_fail;
463                         cp = stop_at_slash(sp, strlen(sp));
464                         if (!cp || cp == sp) {
465                         free_both_and_fail:
466                                 free(sp);
467                                 goto free_first_and_fail;
468                         }
469                         /* They must match, otherwise ignore */
470                         if (strcmp(cp+1, first))
471                                 goto free_both_and_fail;
472                         free(sp);
473                         return first;
474                 }
475
476                 /* unquoted second */
477                 cp = stop_at_slash(second, line + llen - second);
478                 if (!cp || cp == second)
479                         goto free_first_and_fail;
480                 cp++;
481                 if (line + llen - cp != len + 1 ||
482                     memcmp(first, cp, len))
483                         goto free_first_and_fail;
484                 return first;
485         }
486
487         /* unquoted first name */
488         name = stop_at_slash(line, llen);
489         if (!name || name == line)
490                 return NULL;
491
492         name++;
493
494         /* since the first name is unquoted, a dq if exists must be
495          * the beginning of the second name.
496          */
497         for (second = name; second < line + llen; second++) {
498                 if (*second == '"') {
499                         const char *cp = second;
500                         const char *np;
501                         char *sp = unquote_c_style(second, NULL);
502
503                         if (!sp)
504                                 return NULL;
505                         np = stop_at_slash(sp, strlen(sp));
506                         if (!np || np == sp) {
507                         free_second_and_fail:
508                                 free(sp);
509                                 return NULL;
510                         }
511                         np++;
512                         len = strlen(np);
513                         if (len < cp - name &&
514                             !strncmp(np, name, len) &&
515                             isspace(name[len])) {
516                                 /* Good */
517                                 memmove(sp, np, len + 1);
518                                 return sp;
519                         }
520                         goto free_second_and_fail;
521                 }
522         }
523
524         /*
525          * Accept a name only if it shows up twice, exactly the same
526          * form.
527          */
528         for (len = 0 ; ; len++) {
529                 char c = name[len];
530
531                 switch (c) {
532                 default:
533                         continue;
534                 case '\n':
535                         return NULL;
536                 case '\t': case ' ':
537                         second = name+len;
538                         for (;;) {
539                                 char c = *second++;
540                                 if (c == '\n')
541                                         return NULL;
542                                 if (c == '/')
543                                         break;
544                         }
545                         if (second[len] == '\n' && !memcmp(name, second, len)) {
546                                 char *ret = xmalloc(len + 1);
547                                 memcpy(ret, name, len);
548                                 ret[len] = 0;
549                                 return ret;
550                         }
551                 }
552         }
553         return NULL;
554 }
555
556 /* Verify that we recognize the lines following a git header */
557 static int parse_git_header(char *line, int len, unsigned int size, struct patch *patch)
558 {
559         unsigned long offset;
560
561         /* A git diff has explicit new/delete information, so we don't guess */
562         patch->is_new = 0;
563         patch->is_delete = 0;
564
565         /*
566          * Some things may not have the old name in the
567          * rest of the headers anywhere (pure mode changes,
568          * or removing or adding empty files), so we get
569          * the default name from the header.
570          */
571         patch->def_name = git_header_name(line, len);
572
573         line += len;
574         size -= len;
575         linenr++;
576         for (offset = len ; size > 0 ; offset += len, size -= len, line += len, linenr++) {
577                 static const struct opentry {
578                         const char *str;
579                         int (*fn)(const char *, struct patch *);
580                 } optable[] = {
581                         { "@@ -", gitdiff_hdrend },
582                         { "--- ", gitdiff_oldname },
583                         { "+++ ", gitdiff_newname },
584                         { "old mode ", gitdiff_oldmode },
585                         { "new mode ", gitdiff_newmode },
586                         { "deleted file mode ", gitdiff_delete },
587                         { "new file mode ", gitdiff_newfile },
588                         { "copy from ", gitdiff_copysrc },
589                         { "copy to ", gitdiff_copydst },
590                         { "rename old ", gitdiff_renamesrc },
591                         { "rename new ", gitdiff_renamedst },
592                         { "rename from ", gitdiff_renamesrc },
593                         { "rename to ", gitdiff_renamedst },
594                         { "similarity index ", gitdiff_similarity },
595                         { "dissimilarity index ", gitdiff_dissimilarity },
596                         { "index ", gitdiff_index },
597                         { "", gitdiff_unrecognized },
598                 };
599                 int i;
600
601                 len = linelen(line, size);
602                 if (!len || line[len-1] != '\n')
603                         break;
604                 for (i = 0; i < sizeof(optable) / sizeof(optable[0]); i++) {
605                         const struct opentry *p = optable + i;
606                         int oplen = strlen(p->str);
607                         if (len < oplen || memcmp(p->str, line, oplen))
608                                 continue;
609                         if (p->fn(line + oplen, patch) < 0)
610                                 return offset;
611                         break;
612                 }
613         }
614
615         return offset;
616 }
617
618 static int parse_num(const char *line, unsigned long *p)
619 {
620         char *ptr;
621
622         if (!isdigit(*line))
623                 return 0;
624         *p = strtoul(line, &ptr, 10);
625         return ptr - line;
626 }
627
628 static int parse_range(const char *line, int len, int offset, const char *expect,
629                         unsigned long *p1, unsigned long *p2)
630 {
631         int digits, ex;
632
633         if (offset < 0 || offset >= len)
634                 return -1;
635         line += offset;
636         len -= offset;
637
638         digits = parse_num(line, p1);
639         if (!digits)
640                 return -1;
641
642         offset += digits;
643         line += digits;
644         len -= digits;
645
646         *p2 = *p1;
647         if (*line == ',') {
648                 digits = parse_num(line+1, p2);
649                 if (!digits)
650                         return -1;
651
652                 offset += digits+1;
653                 line += digits+1;
654                 len -= digits+1;
655         }
656
657         ex = strlen(expect);
658         if (ex > len)
659                 return -1;
660         if (memcmp(line, expect, ex))
661                 return -1;
662
663         return offset + ex;
664 }
665
666 /*
667  * Parse a unified diff fragment header of the
668  * form "@@ -a,b +c,d @@"
669  */
670 static int parse_fragment_header(char *line, int len, struct fragment *fragment)
671 {
672         int offset;
673
674         if (!len || line[len-1] != '\n')
675                 return -1;
676
677         /* Figure out the number of lines in a fragment */
678         offset = parse_range(line, len, 4, " +", &fragment->oldpos, &fragment->oldlines);
679         offset = parse_range(line, len, offset, " @@", &fragment->newpos, &fragment->newlines);
680
681         return offset;
682 }
683
684 static int find_header(char *line, unsigned long size, int *hdrsize, struct patch *patch)
685 {
686         unsigned long offset, len;
687
688         patch->is_rename = patch->is_copy = 0;
689         patch->is_new = patch->is_delete = -1;
690         patch->old_mode = patch->new_mode = 0;
691         patch->old_name = patch->new_name = NULL;
692         for (offset = 0; size > 0; offset += len, size -= len, line += len, linenr++) {
693                 unsigned long nextlen;
694
695                 len = linelen(line, size);
696                 if (!len)
697                         break;
698
699                 /* Testing this early allows us to take a few shortcuts.. */
700                 if (len < 6)
701                         continue;
702
703                 /*
704                  * Make sure we don't find any unconnected patch fragmants.
705                  * That's a sign that we didn't find a header, and that a
706                  * patch has become corrupted/broken up.
707                  */
708                 if (!memcmp("@@ -", line, 4)) {
709                         struct fragment dummy;
710                         if (parse_fragment_header(line, len, &dummy) < 0)
711                                 continue;
712                         error("patch fragment without header at line %d: %.*s", linenr, (int)len-1, line);
713                 }
714
715                 if (size < len + 6)
716                         break;
717
718                 /*
719                  * Git patch? It might not have a real patch, just a rename
720                  * or mode change, so we handle that specially
721                  */
722                 if (!memcmp("diff --git ", line, 11)) {
723                         int git_hdr_len = parse_git_header(line, len, size, patch);
724                         if (git_hdr_len <= len)
725                                 continue;
726                         if (!patch->old_name && !patch->new_name) {
727                                 if (!patch->def_name)
728                                         die("git diff header lacks filename information (line %d)", linenr);
729                                 patch->old_name = patch->new_name = patch->def_name;
730                         }
731                         *hdrsize = git_hdr_len;
732                         return offset;
733                 }
734
735                 /** --- followed by +++ ? */
736                 if (memcmp("--- ", line,  4) || memcmp("+++ ", line + len, 4))
737                         continue;
738
739                 /*
740                  * We only accept unified patches, so we want it to
741                  * at least have "@@ -a,b +c,d @@\n", which is 14 chars
742                  * minimum
743                  */
744                 nextlen = linelen(line + len, size - len);
745                 if (size < nextlen + 14 || memcmp("@@ -", line + len + nextlen, 4))
746                         continue;
747
748                 /* Ok, we'll consider it a patch */
749                 parse_traditional_patch(line, line+len, patch);
750                 *hdrsize = len + nextlen;
751                 linenr += 2;
752                 return offset;
753         }
754         return -1;
755 }
756
757 /*
758  * Parse a unified diff. Note that this really needs
759  * to parse each fragment separately, since the only
760  * way to know the difference between a "---" that is
761  * part of a patch, and a "---" that starts the next
762  * patch is to look at the line counts..
763  */
764 static int parse_fragment(char *line, unsigned long size, struct patch *patch, struct fragment *fragment)
765 {
766         int added, deleted;
767         int len = linelen(line, size), offset;
768         unsigned long oldlines, newlines;
769
770         offset = parse_fragment_header(line, len, fragment);
771         if (offset < 0)
772                 return -1;
773         oldlines = fragment->oldlines;
774         newlines = fragment->newlines;
775
776         if (patch->is_new < 0) {
777                 patch->is_new =  !oldlines;
778                 if (!oldlines)
779                         patch->old_name = NULL;
780         }
781         if (patch->is_delete < 0) {
782                 patch->is_delete = !newlines;
783                 if (!newlines)
784                         patch->new_name = NULL;
785         }
786
787         if (patch->is_new != !oldlines)
788                 return error("new file depends on old contents");
789         if (patch->is_delete != !newlines) {
790                 if (newlines)
791                         return error("deleted file still has contents");
792                 fprintf(stderr, "** warning: file %s becomes empty but is not deleted\n", patch->new_name);
793         }
794
795         /* Parse the thing.. */
796         line += len;
797         size -= len;
798         linenr++;
799         added = deleted = 0;
800         for (offset = len; size > 0; offset += len, size -= len, line += len, linenr++) {
801                 if (!oldlines && !newlines)
802                         break;
803                 len = linelen(line, size);
804                 if (!len || line[len-1] != '\n')
805                         return -1;
806                 switch (*line) {
807                 default:
808                         return -1;
809                 case ' ':
810                         oldlines--;
811                         newlines--;
812                         break;
813                 case '-':
814                         deleted++;
815                         oldlines--;
816                         break;
817                 case '+':
818                         added++;
819                         newlines--;
820                         break;
821
822                 /* We allow "\ No newline at end of file". Depending
823                  * on locale settings when the patch was produced we
824                  * don't know what this line looks like. The only
825                  * thing we do know is that it begins with "\ ".
826                  * Checking for 12 is just for sanity check -- any
827                  * l10n of "\ No newline..." is at least that long.
828                  */
829                 case '\\':
830                         if (len < 12 || memcmp(line, "\\ ", 2))
831                                 return -1;
832                         break;
833                 }
834         }
835         /* If a fragment ends with an incomplete line, we failed to include
836          * it in the above loop because we hit oldlines == newlines == 0
837          * before seeing it.
838          */
839         if (12 < size && !memcmp(line, "\\ ", 2))
840                 offset += linelen(line, size);
841
842         patch->lines_added += added;
843         patch->lines_deleted += deleted;
844         return offset;
845 }
846
847 static int parse_single_patch(char *line, unsigned long size, struct patch *patch)
848 {
849         unsigned long offset = 0;
850         struct fragment **fragp = &patch->fragments;
851
852         while (size > 4 && !memcmp(line, "@@ -", 4)) {
853                 struct fragment *fragment;
854                 int len;
855
856                 fragment = xmalloc(sizeof(*fragment));
857                 memset(fragment, 0, sizeof(*fragment));
858                 len = parse_fragment(line, size, patch, fragment);
859                 if (len <= 0)
860                         die("corrupt patch at line %d", linenr);
861
862                 fragment->patch = line;
863                 fragment->size = len;
864
865                 *fragp = fragment;
866                 fragp = &fragment->next;
867
868                 offset += len;
869                 line += len;
870                 size -= len;
871         }
872         return offset;
873 }
874
875 static inline int metadata_changes(struct patch *patch)
876 {
877         return  patch->is_rename > 0 ||
878                 patch->is_copy > 0 ||
879                 patch->is_new > 0 ||
880                 patch->is_delete ||
881                 (patch->old_mode && patch->new_mode &&
882                  patch->old_mode != patch->new_mode);
883 }
884
885 static int parse_chunk(char *buffer, unsigned long size, struct patch *patch)
886 {
887         int hdrsize, patchsize;
888         int offset = find_header(buffer, size, &hdrsize, patch);
889
890         if (offset < 0)
891                 return offset;
892
893         patchsize = parse_single_patch(buffer + offset + hdrsize, size - offset - hdrsize, patch);
894
895         if (!patchsize) {
896                 static const char *binhdr[] = {
897                         "Binary files ",
898                         "Files ",
899                         NULL,
900                 };
901                 int i;
902                 int hd = hdrsize + offset;
903                 unsigned long llen = linelen(buffer + hd, size - hd);
904
905                 if (!memcmp(" differ\n", buffer + hd + llen - 8, 8))
906                         for (i = 0; binhdr[i]; i++) {
907                                 int len = strlen(binhdr[i]);
908                                 if (len < size - hd &&
909                                     !memcmp(binhdr[i], buffer + hd, len)) {
910                                         patch->is_binary = 1;
911                                         break;
912                                 }
913                         }
914
915                 /* Empty patch cannot be applied if:
916                  * - it is a binary patch and we do not do binary_replace, or
917                  * - text patch without metadata change
918                  */
919                 if ((apply || check) &&
920                     (patch->is_binary
921                      ? !allow_binary_replacement
922                      : !metadata_changes(patch)))
923                         die("patch with only garbage at line %d", linenr);
924         }
925
926         return offset + hdrsize + patchsize;
927 }
928
929 static const char pluses[] = "++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++";
930 static const char minuses[]= "----------------------------------------------------------------------";
931
932 static void show_stats(struct patch *patch)
933 {
934         const char *prefix = "";
935         char *name = patch->new_name;
936         char *qname = NULL;
937         int len, max, add, del, total;
938
939         if (!name)
940                 name = patch->old_name;
941
942         if (0 < (len = quote_c_style(name, NULL, NULL, 0))) {
943                 qname = xmalloc(len + 1);
944                 quote_c_style(name, qname, NULL, 0);
945                 name = qname;
946         }
947
948         /*
949          * "scale" the filename
950          */
951         len = strlen(name);
952         max = max_len;
953         if (max > 50)
954                 max = 50;
955         if (len > max) {
956                 char *slash;
957                 prefix = "...";
958                 max -= 3;
959                 name += len - max;
960                 slash = strchr(name, '/');
961                 if (slash)
962                         name = slash;
963         }
964         len = max;
965
966         /*
967          * scale the add/delete
968          */
969         max = max_change;
970         if (max + len > 70)
971                 max = 70 - len;
972
973         add = patch->lines_added;
974         del = patch->lines_deleted;
975         total = add + del;
976
977         if (max_change > 0) {
978                 total = (total * max + max_change / 2) / max_change;
979                 add = (add * max + max_change / 2) / max_change;
980                 del = total - add;
981         }
982         if (patch->is_binary)
983                 printf(" %s%-*s |  Bin\n", prefix, len, name);
984         else
985                 printf(" %s%-*s |%5d %.*s%.*s\n", prefix,
986                        len, name, patch->lines_added + patch->lines_deleted,
987                        add, pluses, del, minuses);
988         if (qname)
989                 free(qname);
990 }
991
992 static int read_old_data(struct stat *st, const char *path, void *buf, unsigned long size)
993 {
994         int fd;
995         unsigned long got;
996
997         switch (st->st_mode & S_IFMT) {
998         case S_IFLNK:
999                 return readlink(path, buf, size);
1000         case S_IFREG:
1001                 fd = open(path, O_RDONLY);
1002                 if (fd < 0)
1003                         return error("unable to open %s", path);
1004                 got = 0;
1005                 for (;;) {
1006                         int ret = read(fd, buf + got, size - got);
1007                         if (ret < 0) {
1008                                 if (errno == EAGAIN)
1009                                         continue;
1010                                 break;
1011                         }
1012                         if (!ret)
1013                                 break;
1014                         got += ret;
1015                 }
1016                 close(fd);
1017                 return got;
1018
1019         default:
1020                 return -1;
1021         }
1022 }
1023
1024 static int find_offset(const char *buf, unsigned long size, const char *fragment, unsigned long fragsize, int line)
1025 {
1026         int i;
1027         unsigned long start, backwards, forwards;
1028
1029         if (fragsize > size)
1030                 return -1;
1031
1032         start = 0;
1033         if (line > 1) {
1034                 unsigned long offset = 0;
1035                 i = line-1;
1036                 while (offset + fragsize <= size) {
1037                         if (buf[offset++] == '\n') {
1038                                 start = offset;
1039                                 if (!--i)
1040                                         break;
1041                         }
1042                 }
1043         }
1044
1045         /* Exact line number? */
1046         if (!memcmp(buf + start, fragment, fragsize))
1047                 return start;
1048
1049         /*
1050          * There's probably some smart way to do this, but I'll leave
1051          * that to the smart and beautiful people. I'm simple and stupid.
1052          */
1053         backwards = start;
1054         forwards = start;
1055         for (i = 0; ; i++) {
1056                 unsigned long try;
1057                 int n;
1058
1059                 /* "backward" */
1060                 if (i & 1) {
1061                         if (!backwards) {
1062                                 if (forwards + fragsize > size)
1063                                         break;
1064                                 continue;
1065                         }
1066                         do {
1067                                 --backwards;
1068                         } while (backwards && buf[backwards-1] != '\n');
1069                         try = backwards;
1070                 } else {
1071                         while (forwards + fragsize <= size) {
1072                                 if (buf[forwards++] == '\n')
1073                                         break;
1074                         }
1075                         try = forwards;
1076                 }
1077
1078                 if (try + fragsize > size)
1079                         continue;
1080                 if (memcmp(buf + try, fragment, fragsize))
1081                         continue;
1082                 n = (i >> 1)+1;
1083                 if (i & 1)
1084                         n = -n;
1085                 return try;
1086         }
1087
1088         /*
1089          * We should start searching forward and backward.
1090          */
1091         return -1;
1092 }
1093
1094 struct buffer_desc {
1095         char *buffer;
1096         unsigned long size;
1097         unsigned long alloc;
1098 };
1099
1100 static int apply_one_fragment(struct buffer_desc *desc, struct fragment *frag)
1101 {
1102         char *buf = desc->buffer;
1103         const char *patch = frag->patch;
1104         int offset, size = frag->size;
1105         char *old = xmalloc(size);
1106         char *new = xmalloc(size);
1107         int oldsize = 0, newsize = 0;
1108
1109         while (size > 0) {
1110                 int len = linelen(patch, size);
1111                 int plen;
1112
1113                 if (!len)
1114                         break;
1115
1116                 /*
1117                  * "plen" is how much of the line we should use for
1118                  * the actual patch data. Normally we just remove the
1119                  * first character on the line, but if the line is
1120                  * followed by "\ No newline", then we also remove the
1121                  * last one (which is the newline, of course).
1122                  */
1123                 plen = len-1;
1124                 if (len < size && patch[len] == '\\')
1125                         plen--;
1126                 switch (*patch) {
1127                 case ' ':
1128                 case '-':
1129                         memcpy(old + oldsize, patch + 1, plen);
1130                         oldsize += plen;
1131                         if (*patch == '-')
1132                                 break;
1133                 /* Fall-through for ' ' */
1134                 case '+':
1135                         if (*patch != '+' || !no_add) {
1136                                 memcpy(new + newsize, patch + 1, plen);
1137                                 newsize += plen;
1138                         }
1139                         break;
1140                 case '@': case '\\':
1141                         /* Ignore it, we already handled it */
1142                         break;
1143                 default:
1144                         return -1;
1145                 }
1146                 patch += len;
1147                 size -= len;
1148         }
1149
1150         offset = find_offset(buf, desc->size, old, oldsize, frag->newpos);
1151         if (offset >= 0) {
1152                 int diff = newsize - oldsize;
1153                 unsigned long size = desc->size + diff;
1154                 unsigned long alloc = desc->alloc;
1155
1156                 if (size > alloc) {
1157                         alloc = size + 8192;
1158                         desc->alloc = alloc;
1159                         buf = xrealloc(buf, alloc);
1160                         desc->buffer = buf;
1161                 }
1162                 desc->size = size;
1163                 memmove(buf + offset + newsize, buf + offset + oldsize, size - offset - newsize);
1164                 memcpy(buf + offset, new, newsize);
1165                 offset = 0;
1166         }
1167
1168         free(old);
1169         free(new);
1170         return offset;
1171 }
1172
1173 static int apply_fragments(struct buffer_desc *desc, struct patch *patch)
1174 {
1175         struct fragment *frag = patch->fragments;
1176         const char *name = patch->old_name ? patch->old_name : patch->new_name;
1177
1178         if (patch->is_binary) {
1179                 unsigned char sha1[20];
1180
1181                 if (!allow_binary_replacement)
1182                         return error("cannot apply binary patch to '%s' "
1183                                      "without --allow-binary-replacement",
1184                                      name);
1185
1186                 /* For safety, we require patch index line to contain
1187                  * full 40-byte textual SHA1 for old and new, at least for now.
1188                  */
1189                 if (strlen(patch->old_sha1_prefix) != 40 ||
1190                     strlen(patch->new_sha1_prefix) != 40 ||
1191                     get_sha1_hex(patch->old_sha1_prefix, sha1) ||
1192                     get_sha1_hex(patch->new_sha1_prefix, sha1))
1193                         return error("cannot apply binary patch to '%s' "
1194                                      "without full index line", name);
1195
1196                 if (patch->old_name) {
1197                         unsigned char hdr[50];
1198                         int hdrlen;
1199
1200                         /* See if the old one matches what the patch
1201                          * applies to.
1202                          */
1203                         write_sha1_file_prepare(desc->buffer, desc->size,
1204                                                 "blob", sha1, hdr, &hdrlen);
1205                         if (strcmp(sha1_to_hex(sha1), patch->old_sha1_prefix))
1206                                 return error("the patch applies to '%s' (%s), "
1207                                              "which does not match the "
1208                                              "current contents.",
1209                                              name, sha1_to_hex(sha1));
1210                 }
1211                 else {
1212                         /* Otherwise, the old one must be empty. */
1213                         if (desc->size)
1214                                 return error("the patch applies to an empty "
1215                                              "'%s' but it is not empty", name);
1216                 }
1217
1218                 /* For now, we do not record post-image data in the patch,
1219                  * and require the object already present in the recipient's
1220                  * object database.
1221                  */
1222                 if (desc->buffer) {
1223                         free(desc->buffer);
1224                         desc->alloc = desc->size = 0;
1225                 }
1226                 get_sha1_hex(patch->new_sha1_prefix, sha1);
1227
1228                 if (memcmp(sha1, null_sha1, 20)) {
1229                         char type[10];
1230                         unsigned long size;
1231
1232                         desc->buffer = read_sha1_file(sha1, type, &size);
1233                         if (!desc->buffer)
1234                                 return error("the necessary postimage %s for "
1235                                              "'%s' does not exist",
1236                                              patch->new_sha1_prefix, name);
1237                         desc->alloc = desc->size = size;
1238                 }
1239
1240                 return 0;
1241         }
1242
1243         while (frag) {
1244                 if (apply_one_fragment(desc, frag) < 0)
1245                         return error("patch failed: %s:%ld",
1246                                      name, frag->oldpos);
1247                 frag = frag->next;
1248         }
1249         return 0;
1250 }
1251
1252 static int apply_data(struct patch *patch, struct stat *st)
1253 {
1254         char *buf;
1255         unsigned long size, alloc;
1256         struct buffer_desc desc;
1257
1258         size = 0;
1259         alloc = 0;
1260         buf = NULL;
1261         if (patch->old_name) {
1262                 size = st->st_size;
1263                 alloc = size + 8192;
1264                 buf = xmalloc(alloc);
1265                 if (read_old_data(st, patch->old_name, buf, alloc) != size)
1266                         return error("read of %s failed", patch->old_name);
1267         }
1268
1269         desc.size = size;
1270         desc.alloc = alloc;
1271         desc.buffer = buf;
1272         if (apply_fragments(&desc, patch) < 0)
1273                 return -1;
1274         patch->result = desc.buffer;
1275         patch->resultsize = desc.size;
1276
1277         if (patch->is_delete && patch->resultsize)
1278                 return error("removal patch leaves file contents");
1279
1280         return 0;
1281 }
1282
1283 static int check_patch(struct patch *patch)
1284 {
1285         struct stat st;
1286         const char *old_name = patch->old_name;
1287         const char *new_name = patch->new_name;
1288         const char *name = old_name ? old_name : new_name;
1289
1290         if (old_name) {
1291                 int changed;
1292                 int stat_ret = lstat(old_name, &st);
1293
1294                 if (check_index) {
1295                         int pos = cache_name_pos(old_name, strlen(old_name));
1296                         if (pos < 0)
1297                                 return error("%s: does not exist in index",
1298                                              old_name);
1299                         if (stat_ret < 0) {
1300                                 struct checkout costate;
1301                                 if (errno != ENOENT)
1302                                         return error("%s: %s", old_name,
1303                                                      strerror(errno));
1304                                 /* checkout */
1305                                 costate.base_dir = "";
1306                                 costate.base_dir_len = 0;
1307                                 costate.force = 0;
1308                                 costate.quiet = 0;
1309                                 costate.not_new = 0;
1310                                 costate.refresh_cache = 1;
1311                                 if (checkout_entry(active_cache[pos],
1312                                                    &costate) ||
1313                                     lstat(old_name, &st))
1314                                         return -1;
1315                         }
1316
1317                         changed = ce_match_stat(active_cache[pos], &st);
1318                         if (changed)
1319                                 return error("%s: does not match index",
1320                                              old_name);
1321                 }
1322                 else if (stat_ret < 0)
1323                         return error("%s: %s", old_name, strerror(errno));
1324
1325                 if (patch->is_new < 0)
1326                         patch->is_new = 0;
1327                 st.st_mode = ntohl(create_ce_mode(st.st_mode));
1328                 if (!patch->old_mode)
1329                         patch->old_mode = st.st_mode;
1330                 if ((st.st_mode ^ patch->old_mode) & S_IFMT)
1331                         return error("%s: wrong type", old_name);
1332                 if (st.st_mode != patch->old_mode)
1333                         fprintf(stderr, "warning: %s has type %o, expected %o\n",
1334                                 old_name, st.st_mode, patch->old_mode);
1335         }
1336
1337         if (new_name && (patch->is_new | patch->is_rename | patch->is_copy)) {
1338                 if (check_index && cache_name_pos(new_name, strlen(new_name)) >= 0)
1339                         return error("%s: already exists in index", new_name);
1340                 if (!lstat(new_name, &st))
1341                         return error("%s: already exists in working directory", new_name);
1342                 if (errno != ENOENT)
1343                         return error("%s: %s", new_name, strerror(errno));
1344                 if (!patch->new_mode) {
1345                         if (patch->is_new)
1346                                 patch->new_mode = S_IFREG | 0644;
1347                         else
1348                                 patch->new_mode = patch->old_mode;
1349                 }
1350         }
1351
1352         if (new_name && old_name) {
1353                 int same = !strcmp(old_name, new_name);
1354                 if (!patch->new_mode)
1355                         patch->new_mode = patch->old_mode;
1356                 if ((patch->old_mode ^ patch->new_mode) & S_IFMT)
1357                         return error("new mode (%o) of %s does not match old mode (%o)%s%s",
1358                                 patch->new_mode, new_name, patch->old_mode,
1359                                 same ? "" : " of ", same ? "" : old_name);
1360         }       
1361
1362         if (apply_data(patch, &st) < 0)
1363                 return error("%s: patch does not apply", name);
1364         return 0;
1365 }
1366
1367 static int check_patch_list(struct patch *patch)
1368 {
1369         int error = 0;
1370
1371         for (;patch ; patch = patch->next)
1372                 error |= check_patch(patch);
1373         return error;
1374 }
1375
1376 static inline int is_null_sha1(const unsigned char *sha1)
1377 {
1378         return !memcmp(sha1, null_sha1, 20);
1379 }
1380
1381 static void show_index_list(struct patch *list)
1382 {
1383         struct patch *patch;
1384
1385         /* Once we start supporting the reverse patch, it may be
1386          * worth showing the new sha1 prefix, but until then...
1387          */
1388         for (patch = list; patch; patch = patch->next) {
1389                 const unsigned char *sha1_ptr;
1390                 unsigned char sha1[20];
1391                 const char *name;
1392
1393                 name = patch->old_name ? patch->old_name : patch->new_name;
1394                 if (patch->is_new)
1395                         sha1_ptr = null_sha1;
1396                 else if (get_sha1(patch->old_sha1_prefix, sha1))
1397                         die("sha1 information is lacking or useless (%s).",
1398                             name);
1399                 else
1400                         sha1_ptr = sha1;
1401
1402                 printf("%06o %s ",patch->old_mode, sha1_to_hex(sha1_ptr));
1403                 if (line_termination && quote_c_style(name, NULL, NULL, 0))
1404                         quote_c_style(name, NULL, stdout, 0);
1405                 else
1406                         fputs(name, stdout);
1407                 putchar(line_termination);
1408         }
1409 }
1410
1411 static void stat_patch_list(struct patch *patch)
1412 {
1413         int files, adds, dels;
1414
1415         for (files = adds = dels = 0 ; patch ; patch = patch->next) {
1416                 files++;
1417                 adds += patch->lines_added;
1418                 dels += patch->lines_deleted;
1419                 show_stats(patch);
1420         }
1421
1422         printf(" %d files changed, %d insertions(+), %d deletions(-)\n", files, adds, dels);
1423 }
1424
1425 static void numstat_patch_list(struct patch *patch)
1426 {
1427         for ( ; patch; patch = patch->next) {
1428                 const char *name;
1429                 name = patch->old_name ? patch->old_name : patch->new_name;
1430                 printf("%d\t%d\t", patch->lines_added, patch->lines_deleted);
1431                 if (line_termination && quote_c_style(name, NULL, NULL, 0))
1432                         quote_c_style(name, NULL, stdout, 0);
1433                 else
1434                         fputs(name, stdout);
1435                 putchar('\n');
1436         }
1437 }
1438
1439 static void show_file_mode_name(const char *newdelete, unsigned int mode, const char *name)
1440 {
1441         if (mode)
1442                 printf(" %s mode %06o %s\n", newdelete, mode, name);
1443         else
1444                 printf(" %s %s\n", newdelete, name);
1445 }
1446
1447 static void show_mode_change(struct patch *p, int show_name)
1448 {
1449         if (p->old_mode && p->new_mode && p->old_mode != p->new_mode) {
1450                 if (show_name)
1451                         printf(" mode change %06o => %06o %s\n",
1452                                p->old_mode, p->new_mode, p->new_name);
1453                 else
1454                         printf(" mode change %06o => %06o\n",
1455                                p->old_mode, p->new_mode);
1456         }
1457 }
1458
1459 static void show_rename_copy(struct patch *p)
1460 {
1461         const char *renamecopy = p->is_rename ? "rename" : "copy";
1462         const char *old, *new;
1463
1464         /* Find common prefix */
1465         old = p->old_name;
1466         new = p->new_name;
1467         while (1) {
1468                 const char *slash_old, *slash_new;
1469                 slash_old = strchr(old, '/');
1470                 slash_new = strchr(new, '/');
1471                 if (!slash_old ||
1472                     !slash_new ||
1473                     slash_old - old != slash_new - new ||
1474                     memcmp(old, new, slash_new - new))
1475                         break;
1476                 old = slash_old + 1;
1477                 new = slash_new + 1;
1478         }
1479         /* p->old_name thru old is the common prefix, and old and new
1480          * through the end of names are renames
1481          */
1482         if (old != p->old_name)
1483                 printf(" %s %.*s{%s => %s} (%d%%)\n", renamecopy,
1484                        (int)(old - p->old_name), p->old_name,
1485                        old, new, p->score);
1486         else
1487                 printf(" %s %s => %s (%d%%)\n", renamecopy,
1488                        p->old_name, p->new_name, p->score);
1489         show_mode_change(p, 0);
1490 }
1491
1492 static void summary_patch_list(struct patch *patch)
1493 {
1494         struct patch *p;
1495
1496         for (p = patch; p; p = p->next) {
1497                 if (p->is_new)
1498                         show_file_mode_name("create", p->new_mode, p->new_name);
1499                 else if (p->is_delete)
1500                         show_file_mode_name("delete", p->old_mode, p->old_name);
1501                 else {
1502                         if (p->is_rename || p->is_copy)
1503                                 show_rename_copy(p);
1504                         else {
1505                                 if (p->score) {
1506                                         printf(" rewrite %s (%d%%)\n",
1507                                                p->new_name, p->score);
1508                                         show_mode_change(p, 0);
1509                                 }
1510                                 else
1511                                         show_mode_change(p, 1);
1512                         }
1513                 }
1514         }
1515 }
1516
1517 static void patch_stats(struct patch *patch)
1518 {
1519         int lines = patch->lines_added + patch->lines_deleted;
1520
1521         if (lines > max_change)
1522                 max_change = lines;
1523         if (patch->old_name) {
1524                 int len = quote_c_style(patch->old_name, NULL, NULL, 0);
1525                 if (!len)
1526                         len = strlen(patch->old_name);
1527                 if (len > max_len)
1528                         max_len = len;
1529         }
1530         if (patch->new_name) {
1531                 int len = quote_c_style(patch->new_name, NULL, NULL, 0);
1532                 if (!len)
1533                         len = strlen(patch->new_name);
1534                 if (len > max_len)
1535                         max_len = len;
1536         }
1537 }
1538
1539 static void remove_file(struct patch *patch)
1540 {
1541         if (write_index) {
1542                 if (remove_file_from_cache(patch->old_name) < 0)
1543                         die("unable to remove %s from index", patch->old_name);
1544         }
1545         unlink(patch->old_name);
1546 }
1547
1548 static void add_index_file(const char *path, unsigned mode, void *buf, unsigned long size)
1549 {
1550         struct stat st;
1551         struct cache_entry *ce;
1552         int namelen = strlen(path);
1553         unsigned ce_size = cache_entry_size(namelen);
1554
1555         if (!write_index)
1556                 return;
1557
1558         ce = xmalloc(ce_size);
1559         memset(ce, 0, ce_size);
1560         memcpy(ce->name, path, namelen);
1561         ce->ce_mode = create_ce_mode(mode);
1562         ce->ce_flags = htons(namelen);
1563         if (lstat(path, &st) < 0)
1564                 die("unable to stat newly created file %s", path);
1565         fill_stat_cache_info(ce, &st);
1566         if (write_sha1_file(buf, size, "blob", ce->sha1) < 0)
1567                 die("unable to create backing store for newly created file %s", path);
1568         if (add_cache_entry(ce, ADD_CACHE_OK_TO_ADD) < 0)
1569                 die("unable to add cache entry for %s", path);
1570 }
1571
1572 static void create_subdirectories(const char *path)
1573 {
1574         int len = strlen(path);
1575         char *buf = xmalloc(len + 1);
1576         const char *slash = path;
1577
1578         while ((slash = strchr(slash+1, '/')) != NULL) {
1579                 len = slash - path;
1580                 memcpy(buf, path, len);
1581                 buf[len] = 0;
1582                 if (mkdir(buf, 0777) < 0) {
1583                         if (errno != EEXIST)
1584                                 break;
1585                 }
1586         }
1587         free(buf);
1588 }
1589
1590 static int try_create_file(const char *path, unsigned int mode, const char *buf, unsigned long size)
1591 {
1592         int fd;
1593
1594         if (S_ISLNK(mode))
1595                 return symlink(buf, path);
1596         fd = open(path, O_CREAT | O_EXCL | O_WRONLY | O_TRUNC, (mode & 0100) ? 0777 : 0666);
1597         if (fd < 0)
1598                 return -1;
1599         while (size) {
1600                 int written = write(fd, buf, size);
1601                 if (written < 0) {
1602                         if (errno == EINTR || errno == EAGAIN)
1603                                 continue;
1604                         die("writing file %s: %s", path, strerror(errno));
1605                 }
1606                 if (!written)
1607                         die("out of space writing file %s", path);
1608                 buf += written;
1609                 size -= written;
1610         }
1611         if (close(fd) < 0)
1612                 die("closing file %s: %s", path, strerror(errno));
1613         return 0;
1614 }
1615
1616 /*
1617  * We optimistically assume that the directories exist,
1618  * which is true 99% of the time anyway. If they don't,
1619  * we create them and try again.
1620  */
1621 static void create_one_file(const char *path, unsigned mode, const char *buf, unsigned long size)
1622 {
1623         if (!try_create_file(path, mode, buf, size))
1624                 return;
1625
1626         if (errno == ENOENT) {
1627                 create_subdirectories(path);
1628                 if (!try_create_file(path, mode, buf, size))
1629                         return;
1630         }
1631
1632         if (errno == EEXIST) {
1633                 unsigned int nr = getpid();
1634
1635                 for (;;) {
1636                         const char *newpath;
1637                         newpath = mkpath("%s~%u", path, nr);
1638                         if (!try_create_file(newpath, mode, buf, size)) {
1639                                 if (!rename(newpath, path))
1640                                         return;
1641                                 unlink(newpath);
1642                                 break;
1643                         }
1644                         if (errno != EEXIST)
1645                                 break;
1646                 }                       
1647         }
1648         die("unable to write file %s mode %o", path, mode);
1649 }
1650
1651 static void create_file(struct patch *patch)
1652 {
1653         const char *path = patch->new_name;
1654         unsigned mode = patch->new_mode;
1655         unsigned long size = patch->resultsize;
1656         char *buf = patch->result;
1657
1658         if (!mode)
1659                 mode = S_IFREG | 0644;
1660         create_one_file(path, mode, buf, size); 
1661         add_index_file(path, mode, buf, size);
1662 }
1663
1664 static void write_out_one_result(struct patch *patch)
1665 {
1666         if (patch->is_delete > 0) {
1667                 remove_file(patch);
1668                 return;
1669         }
1670         if (patch->is_new > 0 || patch->is_copy) {
1671                 create_file(patch);
1672                 return;
1673         }
1674         /*
1675          * Rename or modification boils down to the same
1676          * thing: remove the old, write the new
1677          */
1678         remove_file(patch);
1679         create_file(patch);
1680 }
1681
1682 static void write_out_results(struct patch *list, int skipped_patch)
1683 {
1684         if (!list && !skipped_patch)
1685                 die("No changes");
1686
1687         while (list) {
1688                 write_out_one_result(list);
1689                 list = list->next;
1690         }
1691 }
1692
1693 static struct cache_file cache_file;
1694
1695 static struct excludes {
1696         struct excludes *next;
1697         const char *path;
1698 } *excludes;
1699
1700 static int use_patch(struct patch *p)
1701 {
1702         const char *pathname = p->new_name ? p->new_name : p->old_name;
1703         struct excludes *x = excludes;
1704         while (x) {
1705                 if (fnmatch(x->path, pathname, 0) == 0)
1706                         return 0;
1707                 x = x->next;
1708         }
1709         return 1;
1710 }
1711
1712 static int apply_patch(int fd)
1713 {
1714         int newfd;
1715         unsigned long offset, size;
1716         char *buffer = read_patch_file(fd, &size);
1717         struct patch *list = NULL, **listp = &list;
1718         int skipped_patch = 0;
1719
1720         if (!buffer)
1721                 return -1;
1722         offset = 0;
1723         while (size > 0) {
1724                 struct patch *patch;
1725                 int nr;
1726
1727                 patch = xmalloc(sizeof(*patch));
1728                 memset(patch, 0, sizeof(*patch));
1729                 nr = parse_chunk(buffer + offset, size, patch);
1730                 if (nr < 0)
1731                         break;
1732                 if (use_patch(patch)) {
1733                         patch_stats(patch);
1734                         *listp = patch;
1735                         listp = &patch->next;
1736                 } else {
1737                         /* perhaps free it a bit better? */
1738                         free(patch);
1739                         skipped_patch++;
1740                 }
1741                 offset += nr;
1742                 size -= nr;
1743         }
1744
1745         newfd = -1;
1746         write_index = check_index && apply;
1747         if (write_index)
1748                 newfd = hold_index_file_for_update(&cache_file, get_index_file());
1749         if (check_index) {
1750                 if (read_cache() < 0)
1751                         die("unable to read index file");
1752         }
1753
1754         if ((check || apply) && check_patch_list(list) < 0)
1755                 exit(1);
1756
1757         if (apply)
1758                 write_out_results(list, skipped_patch);
1759
1760         if (write_index) {
1761                 if (write_cache(newfd, active_cache, active_nr) ||
1762                     commit_index_file(&cache_file))
1763                         die("Unable to write new cachefile");
1764         }
1765
1766         if (show_index_info)
1767                 show_index_list(list);
1768
1769         if (diffstat)
1770                 stat_patch_list(list);
1771
1772         if (numstat)
1773                 numstat_patch_list(list);
1774
1775         if (summary)
1776                 summary_patch_list(list);
1777
1778         free(buffer);
1779         return 0;
1780 }
1781
1782 int main(int argc, char **argv)
1783 {
1784         int i;
1785         int read_stdin = 1;
1786
1787         for (i = 1; i < argc; i++) {
1788                 const char *arg = argv[i];
1789                 int fd;
1790
1791                 if (!strcmp(arg, "-")) {
1792                         apply_patch(0);
1793                         read_stdin = 0;
1794                         continue;
1795                 }
1796                 if (!strncmp(arg, "--exclude=", 10)) {
1797                         struct excludes *x = xmalloc(sizeof(*x));
1798                         x->path = arg + 10;
1799                         x->next = excludes;
1800                         excludes = x;
1801                         continue;
1802                 }
1803                 if (!strcmp(arg, "--no-add")) {
1804                         no_add = 1;
1805                         continue;
1806                 }
1807                 if (!strcmp(arg, "--stat")) {
1808                         apply = 0;
1809                         diffstat = 1;
1810                         continue;
1811                 }
1812                 if (!strcmp(arg, "--allow-binary-replacement")) {
1813                         allow_binary_replacement = 1;
1814                         continue;
1815                 }
1816                 if (!strcmp(arg, "--numstat")) {
1817                         apply = 0;
1818                         numstat = 1;
1819                         continue;
1820                 }
1821                 if (!strcmp(arg, "--summary")) {
1822                         apply = 0;
1823                         summary = 1;
1824                         continue;
1825                 }
1826                 if (!strcmp(arg, "--check")) {
1827                         apply = 0;
1828                         check = 1;
1829                         continue;
1830                 }
1831                 if (!strcmp(arg, "--index")) {
1832                         check_index = 1;
1833                         continue;
1834                 }
1835                 if (!strcmp(arg, "--apply")) {
1836                         apply = 1;
1837                         continue;
1838                 }
1839                 if (!strcmp(arg, "--index-info")) {
1840                         apply = 0;
1841                         show_index_info = 1;
1842                         continue;
1843                 }
1844                 if (!strcmp(arg, "-z")) {
1845                         line_termination = 0;
1846                         continue;
1847                 }
1848                 fd = open(arg, O_RDONLY);
1849                 if (fd < 0)
1850                         usage(apply_usage);
1851                 read_stdin = 0;
1852                 apply_patch(fd);
1853                 close(fd);
1854         }
1855         if (read_stdin)
1856                 apply_patch(0);
1857         return 0;
1858 }