af9900ff1e8281e9a1d1c4b2ec98e6408ae49027
[git.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 const char *prefix;
20 static int prefix_length = -1;
21
22 static int p_value = 1;
23 static int allow_binary_replacement = 0;
24 static int check_index = 0;
25 static int write_index = 0;
26 static int diffstat = 0;
27 static int numstat = 0;
28 static int summary = 0;
29 static int check = 0;
30 static int apply = 1;
31 static int no_add = 0;
32 static int show_index_info = 0;
33 static int line_termination = '\n';
34 static const char apply_usage[] =
35 "git-apply [--stat] [--numstat] [--summary] [--check] [--index] [--apply] [--no-add] [--index-info] [--allow-binary-replacement] [-z] [-pNUM] <patch>...";
36
37 static enum whitespace_eol {
38         nowarn_whitespace,
39         warn_on_whitespace,
40         error_on_whitespace,
41         strip_whitespace,
42 } new_whitespace = warn_on_whitespace;
43 static int whitespace_error = 0;
44 static int squelch_whitespace_errors = 5;
45 static int applied_after_stripping = 0;
46 static const char *patch_input_file = NULL;
47
48 static void parse_whitespace_option(const char *option)
49 {
50         if (!option) {
51                 new_whitespace = warn_on_whitespace;
52                 return;
53         }
54         if (!strcmp(option, "warn")) {
55                 new_whitespace = warn_on_whitespace;
56                 return;
57         }
58         if (!strcmp(option, "nowarn")) {
59                 new_whitespace = nowarn_whitespace;
60                 return;
61         }
62         if (!strcmp(option, "error")) {
63                 new_whitespace = error_on_whitespace;
64                 return;
65         }
66         if (!strcmp(option, "error-all")) {
67                 new_whitespace = error_on_whitespace;
68                 squelch_whitespace_errors = 0;
69                 return;
70         }
71         if (!strcmp(option, "strip")) {
72                 new_whitespace = strip_whitespace;
73                 return;
74         }
75         die("unrecognized whitespace option '%s'", option);
76 }
77
78 /*
79  * For "diff-stat" like behaviour, we keep track of the biggest change
80  * we've seen, and the longest filename. That allows us to do simple
81  * scaling.
82  */
83 static int max_change, max_len;
84
85 /*
86  * Various "current state", notably line numbers and what
87  * file (and how) we're patching right now.. The "is_xxxx"
88  * things are flags, where -1 means "don't know yet".
89  */
90 static int linenr = 1;
91
92 struct fragment {
93         unsigned long oldpos, oldlines;
94         unsigned long newpos, newlines;
95         const char *patch;
96         int size;
97         struct fragment *next;
98 };
99
100 struct patch {
101         char *new_name, *old_name, *def_name;
102         unsigned int old_mode, new_mode;
103         int is_rename, is_copy, is_new, is_delete, is_binary;
104         int lines_added, lines_deleted;
105         int score;
106         struct fragment *fragments;
107         char *result;
108         unsigned long resultsize;
109         char old_sha1_prefix[41];
110         char new_sha1_prefix[41];
111         struct patch *next;
112 };
113
114 #define CHUNKSIZE (8192)
115 #define SLOP (16)
116
117 static void *read_patch_file(int fd, unsigned long *sizep)
118 {
119         unsigned long size = 0, alloc = CHUNKSIZE;
120         void *buffer = xmalloc(alloc);
121
122         for (;;) {
123                 int nr = alloc - size;
124                 if (nr < 1024) {
125                         alloc += CHUNKSIZE;
126                         buffer = xrealloc(buffer, alloc);
127                         nr = alloc - size;
128                 }
129                 nr = xread(fd, buffer + size, nr);
130                 if (!nr)
131                         break;
132                 if (nr < 0)
133                         die("git-apply: read returned %s", strerror(errno));
134                 size += nr;
135         }
136         *sizep = size;
137
138         /*
139          * Make sure that we have some slop in the buffer
140          * so that we can do speculative "memcmp" etc, and
141          * see to it that it is NUL-filled.
142          */
143         if (alloc < size + SLOP)
144                 buffer = xrealloc(buffer, size + SLOP);
145         memset(buffer + size, 0, SLOP);
146         return buffer;
147 }
148
149 static unsigned long linelen(const char *buffer, unsigned long size)
150 {
151         unsigned long len = 0;
152         while (size--) {
153                 len++;
154                 if (*buffer++ == '\n')
155                         break;
156         }
157         return len;
158 }
159
160 static int is_dev_null(const char *str)
161 {
162         return !memcmp("/dev/null", str, 9) && isspace(str[9]);
163 }
164
165 #define TERM_SPACE      1
166 #define TERM_TAB        2
167
168 static int name_terminate(const char *name, int namelen, int c, int terminate)
169 {
170         if (c == ' ' && !(terminate & TERM_SPACE))
171                 return 0;
172         if (c == '\t' && !(terminate & TERM_TAB))
173                 return 0;
174
175         return 1;
176 }
177
178 static char * find_name(const char *line, char *def, int p_value, int terminate)
179 {
180         int len;
181         const char *start = line;
182         char *name;
183
184         if (*line == '"') {
185                 /* Proposed "new-style" GNU patch/diff format; see
186                  * http://marc.theaimsgroup.com/?l=git&m=112927316408690&w=2
187                  */
188                 name = unquote_c_style(line, NULL);
189                 if (name) {
190                         char *cp = name;
191                         while (p_value) {
192                                 cp = strchr(name, '/');
193                                 if (!cp)
194                                         break;
195                                 cp++;
196                                 p_value--;
197                         }
198                         if (cp) {
199                                 /* name can later be freed, so we need
200                                  * to memmove, not just return cp
201                                  */
202                                 memmove(name, cp, strlen(cp) + 1);
203                                 free(def);
204                                 return name;
205                         }
206                         else {
207                                 free(name);
208                                 name = NULL;
209                         }
210                 }
211         }
212
213         for (;;) {
214                 char c = *line;
215
216                 if (isspace(c)) {
217                         if (c == '\n')
218                                 break;
219                         if (name_terminate(start, line-start, c, terminate))
220                                 break;
221                 }
222                 line++;
223                 if (c == '/' && !--p_value)
224                         start = line;
225         }
226         if (!start)
227                 return def;
228         len = line - start;
229         if (!len)
230                 return def;
231
232         /*
233          * Generally we prefer the shorter name, especially
234          * if the other one is just a variation of that with
235          * something else tacked on to the end (ie "file.orig"
236          * or "file~").
237          */
238         if (def) {
239                 int deflen = strlen(def);
240                 if (deflen < len && !strncmp(start, def, deflen))
241                         return def;
242         }
243
244         name = xmalloc(len + 1);
245         memcpy(name, start, len);
246         name[len] = 0;
247         free(def);
248         return name;
249 }
250
251 /*
252  * Get the name etc info from the --/+++ lines of a traditional patch header
253  *
254  * NOTE! This hardcodes "-p1" behaviour in filename detection.
255  *
256  * FIXME! The end-of-filename heuristics are kind of screwy. For existing
257  * files, we can happily check the index for a match, but for creating a
258  * new file we should try to match whatever "patch" does. I have no idea.
259  */
260 static void parse_traditional_patch(const char *first, const char *second, struct patch *patch)
261 {
262         char *name;
263
264         first += 4;     // skip "--- "
265         second += 4;    // skip "+++ "
266         if (is_dev_null(first)) {
267                 patch->is_new = 1;
268                 patch->is_delete = 0;
269                 name = find_name(second, NULL, p_value, TERM_SPACE | TERM_TAB);
270                 patch->new_name = name;
271         } else if (is_dev_null(second)) {
272                 patch->is_new = 0;
273                 patch->is_delete = 1;
274                 name = find_name(first, NULL, p_value, TERM_SPACE | TERM_TAB);
275                 patch->old_name = name;
276         } else {
277                 name = find_name(first, NULL, p_value, TERM_SPACE | TERM_TAB);
278                 name = find_name(second, name, p_value, TERM_SPACE | TERM_TAB);
279                 patch->old_name = patch->new_name = name;
280         }
281         if (!name)
282                 die("unable to find filename in patch at line %d", linenr);
283 }
284
285 static int gitdiff_hdrend(const char *line, struct patch *patch)
286 {
287         return -1;
288 }
289
290 /*
291  * We're anal about diff header consistency, to make
292  * sure that we don't end up having strange ambiguous
293  * patches floating around.
294  *
295  * As a result, gitdiff_{old|new}name() will check
296  * their names against any previous information, just
297  * to make sure..
298  */
299 static char *gitdiff_verify_name(const char *line, int isnull, char *orig_name, const char *oldnew)
300 {
301         if (!orig_name && !isnull)
302                 return find_name(line, NULL, 1, 0);
303
304         if (orig_name) {
305                 int len;
306                 const char *name;
307                 char *another;
308                 name = orig_name;
309                 len = strlen(name);
310                 if (isnull)
311                         die("git-apply: bad git-diff - expected /dev/null, got %s on line %d", name, linenr);
312                 another = find_name(line, NULL, 1, 0);
313                 if (!another || memcmp(another, name, len))
314                         die("git-apply: bad git-diff - inconsistent %s filename on line %d", oldnew, linenr);
315                 free(another);
316                 return orig_name;
317         }
318         else {
319                 /* expect "/dev/null" */
320                 if (memcmp("/dev/null", line, 9) || line[9] != '\n')
321                         die("git-apply: bad git-diff - expected /dev/null on line %d", linenr);
322                 return NULL;
323         }
324 }
325
326 static int gitdiff_oldname(const char *line, struct patch *patch)
327 {
328         patch->old_name = gitdiff_verify_name(line, patch->is_new, patch->old_name, "old");
329         return 0;
330 }
331
332 static int gitdiff_newname(const char *line, struct patch *patch)
333 {
334         patch->new_name = gitdiff_verify_name(line, patch->is_delete, patch->new_name, "new");
335         return 0;
336 }
337
338 static int gitdiff_oldmode(const char *line, struct patch *patch)
339 {
340         patch->old_mode = strtoul(line, NULL, 8);
341         return 0;
342 }
343
344 static int gitdiff_newmode(const char *line, struct patch *patch)
345 {
346         patch->new_mode = strtoul(line, NULL, 8);
347         return 0;
348 }
349
350 static int gitdiff_delete(const char *line, struct patch *patch)
351 {
352         patch->is_delete = 1;
353         patch->old_name = patch->def_name;
354         return gitdiff_oldmode(line, patch);
355 }
356
357 static int gitdiff_newfile(const char *line, struct patch *patch)
358 {
359         patch->is_new = 1;
360         patch->new_name = patch->def_name;
361         return gitdiff_newmode(line, patch);
362 }
363
364 static int gitdiff_copysrc(const char *line, struct patch *patch)
365 {
366         patch->is_copy = 1;
367         patch->old_name = find_name(line, NULL, 0, 0);
368         return 0;
369 }
370
371 static int gitdiff_copydst(const char *line, struct patch *patch)
372 {
373         patch->is_copy = 1;
374         patch->new_name = find_name(line, NULL, 0, 0);
375         return 0;
376 }
377
378 static int gitdiff_renamesrc(const char *line, struct patch *patch)
379 {
380         patch->is_rename = 1;
381         patch->old_name = find_name(line, NULL, 0, 0);
382         return 0;
383 }
384
385 static int gitdiff_renamedst(const char *line, struct patch *patch)
386 {
387         patch->is_rename = 1;
388         patch->new_name = find_name(line, NULL, 0, 0);
389         return 0;
390 }
391
392 static int gitdiff_similarity(const char *line, struct patch *patch)
393 {
394         if ((patch->score = strtoul(line, NULL, 10)) == ULONG_MAX)
395                 patch->score = 0;
396         return 0;
397 }
398
399 static int gitdiff_dissimilarity(const char *line, struct patch *patch)
400 {
401         if ((patch->score = strtoul(line, NULL, 10)) == ULONG_MAX)
402                 patch->score = 0;
403         return 0;
404 }
405
406 static int gitdiff_index(const char *line, struct patch *patch)
407 {
408         /* index line is N hexadecimal, "..", N hexadecimal,
409          * and optional space with octal mode.
410          */
411         const char *ptr, *eol;
412         int len;
413
414         ptr = strchr(line, '.');
415         if (!ptr || ptr[1] != '.' || 40 < ptr - line)
416                 return 0;
417         len = ptr - line;
418         memcpy(patch->old_sha1_prefix, line, len);
419         patch->old_sha1_prefix[len] = 0;
420
421         line = ptr + 2;
422         ptr = strchr(line, ' ');
423         eol = strchr(line, '\n');
424
425         if (!ptr || eol < ptr)
426                 ptr = eol;
427         len = ptr - line;
428
429         if (40 < len)
430                 return 0;
431         memcpy(patch->new_sha1_prefix, line, len);
432         patch->new_sha1_prefix[len] = 0;
433         if (*ptr == ' ')
434                 patch->new_mode = patch->old_mode = strtoul(ptr+1, NULL, 8);
435         return 0;
436 }
437
438 /*
439  * This is normal for a diff that doesn't change anything: we'll fall through
440  * into the next diff. Tell the parser to break out.
441  */
442 static int gitdiff_unrecognized(const char *line, struct patch *patch)
443 {
444         return -1;
445 }
446
447 static const char *stop_at_slash(const char *line, int llen)
448 {
449         int i;
450
451         for (i = 0; i < llen; i++) {
452                 int ch = line[i];
453                 if (ch == '/')
454                         return line + i;
455         }
456         return NULL;
457 }
458
459 /* This is to extract the same name that appears on "diff --git"
460  * line.  We do not find and return anything if it is a rename
461  * patch, and it is OK because we will find the name elsewhere.
462  * We need to reliably find name only when it is mode-change only,
463  * creation or deletion of an empty file.  In any of these cases,
464  * both sides are the same name under a/ and b/ respectively.
465  */
466 static char *git_header_name(char *line, int llen)
467 {
468         int len;
469         const char *name;
470         const char *second = NULL;
471
472         line += strlen("diff --git ");
473         llen -= strlen("diff --git ");
474
475         if (*line == '"') {
476                 const char *cp;
477                 char *first = unquote_c_style(line, &second);
478                 if (!first)
479                         return NULL;
480
481                 /* advance to the first slash */
482                 cp = stop_at_slash(first, strlen(first));
483                 if (!cp || cp == first) {
484                         /* we do not accept absolute paths */
485                 free_first_and_fail:
486                         free(first);
487                         return NULL;
488                 }
489                 len = strlen(cp+1);
490                 memmove(first, cp+1, len+1); /* including NUL */
491
492                 /* second points at one past closing dq of name.
493                  * find the second name.
494                  */
495                 while ((second < line + llen) && isspace(*second))
496                         second++;
497
498                 if (line + llen <= second)
499                         goto free_first_and_fail;
500                 if (*second == '"') {
501                         char *sp = unquote_c_style(second, NULL);
502                         if (!sp)
503                                 goto free_first_and_fail;
504                         cp = stop_at_slash(sp, strlen(sp));
505                         if (!cp || cp == sp) {
506                         free_both_and_fail:
507                                 free(sp);
508                                 goto free_first_and_fail;
509                         }
510                         /* They must match, otherwise ignore */
511                         if (strcmp(cp+1, first))
512                                 goto free_both_and_fail;
513                         free(sp);
514                         return first;
515                 }
516
517                 /* unquoted second */
518                 cp = stop_at_slash(second, line + llen - second);
519                 if (!cp || cp == second)
520                         goto free_first_and_fail;
521                 cp++;
522                 if (line + llen - cp != len + 1 ||
523                     memcmp(first, cp, len))
524                         goto free_first_and_fail;
525                 return first;
526         }
527
528         /* unquoted first name */
529         name = stop_at_slash(line, llen);
530         if (!name || name == line)
531                 return NULL;
532
533         name++;
534
535         /* since the first name is unquoted, a dq if exists must be
536          * the beginning of the second name.
537          */
538         for (second = name; second < line + llen; second++) {
539                 if (*second == '"') {
540                         const char *cp = second;
541                         const char *np;
542                         char *sp = unquote_c_style(second, NULL);
543
544                         if (!sp)
545                                 return NULL;
546                         np = stop_at_slash(sp, strlen(sp));
547                         if (!np || np == sp) {
548                         free_second_and_fail:
549                                 free(sp);
550                                 return NULL;
551                         }
552                         np++;
553                         len = strlen(np);
554                         if (len < cp - name &&
555                             !strncmp(np, name, len) &&
556                             isspace(name[len])) {
557                                 /* Good */
558                                 memmove(sp, np, len + 1);
559                                 return sp;
560                         }
561                         goto free_second_and_fail;
562                 }
563         }
564
565         /*
566          * Accept a name only if it shows up twice, exactly the same
567          * form.
568          */
569         for (len = 0 ; ; len++) {
570                 char c = name[len];
571
572                 switch (c) {
573                 default:
574                         continue;
575                 case '\n':
576                         return NULL;
577                 case '\t': case ' ':
578                         second = name+len;
579                         for (;;) {
580                                 char c = *second++;
581                                 if (c == '\n')
582                                         return NULL;
583                                 if (c == '/')
584                                         break;
585                         }
586                         if (second[len] == '\n' && !memcmp(name, second, len)) {
587                                 char *ret = xmalloc(len + 1);
588                                 memcpy(ret, name, len);
589                                 ret[len] = 0;
590                                 return ret;
591                         }
592                 }
593         }
594         return NULL;
595 }
596
597 /* Verify that we recognize the lines following a git header */
598 static int parse_git_header(char *line, int len, unsigned int size, struct patch *patch)
599 {
600         unsigned long offset;
601
602         /* A git diff has explicit new/delete information, so we don't guess */
603         patch->is_new = 0;
604         patch->is_delete = 0;
605
606         /*
607          * Some things may not have the old name in the
608          * rest of the headers anywhere (pure mode changes,
609          * or removing or adding empty files), so we get
610          * the default name from the header.
611          */
612         patch->def_name = git_header_name(line, len);
613
614         line += len;
615         size -= len;
616         linenr++;
617         for (offset = len ; size > 0 ; offset += len, size -= len, line += len, linenr++) {
618                 static const struct opentry {
619                         const char *str;
620                         int (*fn)(const char *, struct patch *);
621                 } optable[] = {
622                         { "@@ -", gitdiff_hdrend },
623                         { "--- ", gitdiff_oldname },
624                         { "+++ ", gitdiff_newname },
625                         { "old mode ", gitdiff_oldmode },
626                         { "new mode ", gitdiff_newmode },
627                         { "deleted file mode ", gitdiff_delete },
628                         { "new file mode ", gitdiff_newfile },
629                         { "copy from ", gitdiff_copysrc },
630                         { "copy to ", gitdiff_copydst },
631                         { "rename old ", gitdiff_renamesrc },
632                         { "rename new ", gitdiff_renamedst },
633                         { "rename from ", gitdiff_renamesrc },
634                         { "rename to ", gitdiff_renamedst },
635                         { "similarity index ", gitdiff_similarity },
636                         { "dissimilarity index ", gitdiff_dissimilarity },
637                         { "index ", gitdiff_index },
638                         { "", gitdiff_unrecognized },
639                 };
640                 int i;
641
642                 len = linelen(line, size);
643                 if (!len || line[len-1] != '\n')
644                         break;
645                 for (i = 0; i < sizeof(optable) / sizeof(optable[0]); i++) {
646                         const struct opentry *p = optable + i;
647                         int oplen = strlen(p->str);
648                         if (len < oplen || memcmp(p->str, line, oplen))
649                                 continue;
650                         if (p->fn(line + oplen, patch) < 0)
651                                 return offset;
652                         break;
653                 }
654         }
655
656         return offset;
657 }
658
659 static int parse_num(const char *line, unsigned long *p)
660 {
661         char *ptr;
662
663         if (!isdigit(*line))
664                 return 0;
665         *p = strtoul(line, &ptr, 10);
666         return ptr - line;
667 }
668
669 static int parse_range(const char *line, int len, int offset, const char *expect,
670                         unsigned long *p1, unsigned long *p2)
671 {
672         int digits, ex;
673
674         if (offset < 0 || offset >= len)
675                 return -1;
676         line += offset;
677         len -= offset;
678
679         digits = parse_num(line, p1);
680         if (!digits)
681                 return -1;
682
683         offset += digits;
684         line += digits;
685         len -= digits;
686
687         *p2 = *p1;
688         if (*line == ',') {
689                 digits = parse_num(line+1, p2);
690                 if (!digits)
691                         return -1;
692
693                 offset += digits+1;
694                 line += digits+1;
695                 len -= digits+1;
696         }
697
698         ex = strlen(expect);
699         if (ex > len)
700                 return -1;
701         if (memcmp(line, expect, ex))
702                 return -1;
703
704         return offset + ex;
705 }
706
707 /*
708  * Parse a unified diff fragment header of the
709  * form "@@ -a,b +c,d @@"
710  */
711 static int parse_fragment_header(char *line, int len, struct fragment *fragment)
712 {
713         int offset;
714
715         if (!len || line[len-1] != '\n')
716                 return -1;
717
718         /* Figure out the number of lines in a fragment */
719         offset = parse_range(line, len, 4, " +", &fragment->oldpos, &fragment->oldlines);
720         offset = parse_range(line, len, offset, " @@", &fragment->newpos, &fragment->newlines);
721
722         return offset;
723 }
724
725 static int find_header(char *line, unsigned long size, int *hdrsize, struct patch *patch)
726 {
727         unsigned long offset, len;
728
729         patch->is_rename = patch->is_copy = 0;
730         patch->is_new = patch->is_delete = -1;
731         patch->old_mode = patch->new_mode = 0;
732         patch->old_name = patch->new_name = NULL;
733         for (offset = 0; size > 0; offset += len, size -= len, line += len, linenr++) {
734                 unsigned long nextlen;
735
736                 len = linelen(line, size);
737                 if (!len)
738                         break;
739
740                 /* Testing this early allows us to take a few shortcuts.. */
741                 if (len < 6)
742                         continue;
743
744                 /*
745                  * Make sure we don't find any unconnected patch fragmants.
746                  * That's a sign that we didn't find a header, and that a
747                  * patch has become corrupted/broken up.
748                  */
749                 if (!memcmp("@@ -", line, 4)) {
750                         struct fragment dummy;
751                         if (parse_fragment_header(line, len, &dummy) < 0)
752                                 continue;
753                         error("patch fragment without header at line %d: %.*s", linenr, (int)len-1, line);
754                 }
755
756                 if (size < len + 6)
757                         break;
758
759                 /*
760                  * Git patch? It might not have a real patch, just a rename
761                  * or mode change, so we handle that specially
762                  */
763                 if (!memcmp("diff --git ", line, 11)) {
764                         int git_hdr_len = parse_git_header(line, len, size, patch);
765                         if (git_hdr_len <= len)
766                                 continue;
767                         if (!patch->old_name && !patch->new_name) {
768                                 if (!patch->def_name)
769                                         die("git diff header lacks filename information (line %d)", linenr);
770                                 patch->old_name = patch->new_name = patch->def_name;
771                         }
772                         *hdrsize = git_hdr_len;
773                         return offset;
774                 }
775
776                 /** --- followed by +++ ? */
777                 if (memcmp("--- ", line,  4) || memcmp("+++ ", line + len, 4))
778                         continue;
779
780                 /*
781                  * We only accept unified patches, so we want it to
782                  * at least have "@@ -a,b +c,d @@\n", which is 14 chars
783                  * minimum
784                  */
785                 nextlen = linelen(line + len, size - len);
786                 if (size < nextlen + 14 || memcmp("@@ -", line + len + nextlen, 4))
787                         continue;
788
789                 /* Ok, we'll consider it a patch */
790                 parse_traditional_patch(line, line+len, patch);
791                 *hdrsize = len + nextlen;
792                 linenr += 2;
793                 return offset;
794         }
795         return -1;
796 }
797
798 /*
799  * Parse a unified diff. Note that this really needs
800  * to parse each fragment separately, since the only
801  * way to know the difference between a "---" that is
802  * part of a patch, and a "---" that starts the next
803  * patch is to look at the line counts..
804  */
805 static int parse_fragment(char *line, unsigned long size, struct patch *patch, struct fragment *fragment)
806 {
807         int added, deleted;
808         int len = linelen(line, size), offset;
809         unsigned long oldlines, newlines;
810
811         offset = parse_fragment_header(line, len, fragment);
812         if (offset < 0)
813                 return -1;
814         oldlines = fragment->oldlines;
815         newlines = fragment->newlines;
816
817         if (patch->is_new < 0) {
818                 patch->is_new =  !oldlines;
819                 if (!oldlines)
820                         patch->old_name = NULL;
821         }
822         if (patch->is_delete < 0) {
823                 patch->is_delete = !newlines;
824                 if (!newlines)
825                         patch->new_name = NULL;
826         }
827
828         if (patch->is_new != !oldlines)
829                 return error("new file depends on old contents");
830         if (patch->is_delete != !newlines) {
831                 if (newlines)
832                         return error("deleted file still has contents");
833                 fprintf(stderr, "** warning: file %s becomes empty but is not deleted\n", patch->new_name);
834         }
835
836         /* Parse the thing.. */
837         line += len;
838         size -= len;
839         linenr++;
840         added = deleted = 0;
841         for (offset = len; size > 0; offset += len, size -= len, line += len, linenr++) {
842                 if (!oldlines && !newlines)
843                         break;
844                 len = linelen(line, size);
845                 if (!len || line[len-1] != '\n')
846                         return -1;
847                 switch (*line) {
848                 default:
849                         return -1;
850                 case ' ':
851                         oldlines--;
852                         newlines--;
853                         break;
854                 case '-':
855                         deleted++;
856                         oldlines--;
857                         break;
858                 case '+':
859                         /*
860                          * We know len is at least two, since we have a '+' and
861                          * we checked that the last character was a '\n' above.
862                          * That is, an addition of an empty line would check
863                          * the '+' here.  Sneaky...
864                          */
865                         if ((new_whitespace != nowarn_whitespace) &&
866                             isspace(line[len-2])) {
867                                 whitespace_error++;
868                                 if (squelch_whitespace_errors &&
869                                     squelch_whitespace_errors <
870                                     whitespace_error)
871                                         ;
872                                 else {
873                                         fprintf(stderr, "Adds trailing whitespace.\n%s:%d:%.*s\n",
874                                                 patch_input_file,
875                                                 linenr, len-2, line+1);
876                                 }
877                         }
878                         added++;
879                         newlines--;
880                         break;
881
882                 /* We allow "\ No newline at end of file". Depending
883                  * on locale settings when the patch was produced we
884                  * don't know what this line looks like. The only
885                  * thing we do know is that it begins with "\ ".
886                  * Checking for 12 is just for sanity check -- any
887                  * l10n of "\ No newline..." is at least that long.
888                  */
889                 case '\\':
890                         if (len < 12 || memcmp(line, "\\ ", 2))
891                                 return -1;
892                         break;
893                 }
894         }
895         /* If a fragment ends with an incomplete line, we failed to include
896          * it in the above loop because we hit oldlines == newlines == 0
897          * before seeing it.
898          */
899         if (12 < size && !memcmp(line, "\\ ", 2))
900                 offset += linelen(line, size);
901
902         patch->lines_added += added;
903         patch->lines_deleted += deleted;
904         return offset;
905 }
906
907 static int parse_single_patch(char *line, unsigned long size, struct patch *patch)
908 {
909         unsigned long offset = 0;
910         struct fragment **fragp = &patch->fragments;
911
912         while (size > 4 && !memcmp(line, "@@ -", 4)) {
913                 struct fragment *fragment;
914                 int len;
915
916                 fragment = xmalloc(sizeof(*fragment));
917                 memset(fragment, 0, sizeof(*fragment));
918                 len = parse_fragment(line, size, patch, fragment);
919                 if (len <= 0)
920                         die("corrupt patch at line %d", linenr);
921
922                 fragment->patch = line;
923                 fragment->size = len;
924
925                 *fragp = fragment;
926                 fragp = &fragment->next;
927
928                 offset += len;
929                 line += len;
930                 size -= len;
931         }
932         return offset;
933 }
934
935 static inline int metadata_changes(struct patch *patch)
936 {
937         return  patch->is_rename > 0 ||
938                 patch->is_copy > 0 ||
939                 patch->is_new > 0 ||
940                 patch->is_delete ||
941                 (patch->old_mode && patch->new_mode &&
942                  patch->old_mode != patch->new_mode);
943 }
944
945 static int parse_chunk(char *buffer, unsigned long size, struct patch *patch)
946 {
947         int hdrsize, patchsize;
948         int offset = find_header(buffer, size, &hdrsize, patch);
949
950         if (offset < 0)
951                 return offset;
952
953         patchsize = parse_single_patch(buffer + offset + hdrsize, size - offset - hdrsize, patch);
954
955         if (!patchsize) {
956                 static const char *binhdr[] = {
957                         "Binary files ",
958                         "Files ",
959                         NULL,
960                 };
961                 int i;
962                 int hd = hdrsize + offset;
963                 unsigned long llen = linelen(buffer + hd, size - hd);
964
965                 if (!memcmp(" differ\n", buffer + hd + llen - 8, 8))
966                         for (i = 0; binhdr[i]; i++) {
967                                 int len = strlen(binhdr[i]);
968                                 if (len < size - hd &&
969                                     !memcmp(binhdr[i], buffer + hd, len)) {
970                                         patch->is_binary = 1;
971                                         break;
972                                 }
973                         }
974
975                 /* Empty patch cannot be applied if:
976                  * - it is a binary patch and we do not do binary_replace, or
977                  * - text patch without metadata change
978                  */
979                 if ((apply || check) &&
980                     (patch->is_binary
981                      ? !allow_binary_replacement
982                      : !metadata_changes(patch)))
983                         die("patch with only garbage at line %d", linenr);
984         }
985
986         return offset + hdrsize + patchsize;
987 }
988
989 static const char pluses[] = "++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++";
990 static const char minuses[]= "----------------------------------------------------------------------";
991
992 static void show_stats(struct patch *patch)
993 {
994         const char *prefix = "";
995         char *name = patch->new_name;
996         char *qname = NULL;
997         int len, max, add, del, total;
998
999         if (!name)
1000                 name = patch->old_name;
1001
1002         if (0 < (len = quote_c_style(name, NULL, NULL, 0))) {
1003                 qname = xmalloc(len + 1);
1004                 quote_c_style(name, qname, NULL, 0);
1005                 name = qname;
1006         }
1007
1008         /*
1009          * "scale" the filename
1010          */
1011         len = strlen(name);
1012         max = max_len;
1013         if (max > 50)
1014                 max = 50;
1015         if (len > max) {
1016                 char *slash;
1017                 prefix = "...";
1018                 max -= 3;
1019                 name += len - max;
1020                 slash = strchr(name, '/');
1021                 if (slash)
1022                         name = slash;
1023         }
1024         len = max;
1025
1026         /*
1027          * scale the add/delete
1028          */
1029         max = max_change;
1030         if (max + len > 70)
1031                 max = 70 - len;
1032
1033         add = patch->lines_added;
1034         del = patch->lines_deleted;
1035         total = add + del;
1036
1037         if (max_change > 0) {
1038                 total = (total * max + max_change / 2) / max_change;
1039                 add = (add * max + max_change / 2) / max_change;
1040                 del = total - add;
1041         }
1042         if (patch->is_binary)
1043                 printf(" %s%-*s |  Bin\n", prefix, len, name);
1044         else
1045                 printf(" %s%-*s |%5d %.*s%.*s\n", prefix,
1046                        len, name, patch->lines_added + patch->lines_deleted,
1047                        add, pluses, del, minuses);
1048         if (qname)
1049                 free(qname);
1050 }
1051
1052 static int read_old_data(struct stat *st, const char *path, void *buf, unsigned long size)
1053 {
1054         int fd;
1055         unsigned long got;
1056
1057         switch (st->st_mode & S_IFMT) {
1058         case S_IFLNK:
1059                 return readlink(path, buf, size);
1060         case S_IFREG:
1061                 fd = open(path, O_RDONLY);
1062                 if (fd < 0)
1063                         return error("unable to open %s", path);
1064                 got = 0;
1065                 for (;;) {
1066                         int ret = xread(fd, buf + got, size - got);
1067                         if (ret <= 0)
1068                                 break;
1069                         got += ret;
1070                 }
1071                 close(fd);
1072                 return got;
1073
1074         default:
1075                 return -1;
1076         }
1077 }
1078
1079 static int find_offset(const char *buf, unsigned long size, const char *fragment, unsigned long fragsize, int line)
1080 {
1081         int i;
1082         unsigned long start, backwards, forwards;
1083
1084         if (fragsize > size)
1085                 return -1;
1086
1087         start = 0;
1088         if (line > 1) {
1089                 unsigned long offset = 0;
1090                 i = line-1;
1091                 while (offset + fragsize <= size) {
1092                         if (buf[offset++] == '\n') {
1093                                 start = offset;
1094                                 if (!--i)
1095                                         break;
1096                         }
1097                 }
1098         }
1099
1100         /* Exact line number? */
1101         if (!memcmp(buf + start, fragment, fragsize))
1102                 return start;
1103
1104         /*
1105          * There's probably some smart way to do this, but I'll leave
1106          * that to the smart and beautiful people. I'm simple and stupid.
1107          */
1108         backwards = start;
1109         forwards = start;
1110         for (i = 0; ; i++) {
1111                 unsigned long try;
1112                 int n;
1113
1114                 /* "backward" */
1115                 if (i & 1) {
1116                         if (!backwards) {
1117                                 if (forwards + fragsize > size)
1118                                         break;
1119                                 continue;
1120                         }
1121                         do {
1122                                 --backwards;
1123                         } while (backwards && buf[backwards-1] != '\n');
1124                         try = backwards;
1125                 } else {
1126                         while (forwards + fragsize <= size) {
1127                                 if (buf[forwards++] == '\n')
1128                                         break;
1129                         }
1130                         try = forwards;
1131                 }
1132
1133                 if (try + fragsize > size)
1134                         continue;
1135                 if (memcmp(buf + try, fragment, fragsize))
1136                         continue;
1137                 n = (i >> 1)+1;
1138                 if (i & 1)
1139                         n = -n;
1140                 return try;
1141         }
1142
1143         /*
1144          * We should start searching forward and backward.
1145          */
1146         return -1;
1147 }
1148
1149 struct buffer_desc {
1150         char *buffer;
1151         unsigned long size;
1152         unsigned long alloc;
1153 };
1154
1155 static int apply_line(char *output, const char *patch, int plen)
1156 {
1157         /* plen is number of bytes to be copied from patch,
1158          * starting at patch+1 (patch[0] is '+').  Typically
1159          * patch[plen] is '\n'.
1160          */
1161         int add_nl_to_tail = 0;
1162         if ((new_whitespace == strip_whitespace) &&
1163             1 < plen && isspace(patch[plen-1])) {
1164                 if (patch[plen] == '\n')
1165                         add_nl_to_tail = 1;
1166                 plen--;
1167                 while (0 < plen && isspace(patch[plen]))
1168                         plen--;
1169                 applied_after_stripping++;
1170         }
1171         memcpy(output, patch + 1, plen);
1172         if (add_nl_to_tail)
1173                 output[plen++] = '\n';
1174         return plen;
1175 }
1176
1177 static int apply_one_fragment(struct buffer_desc *desc, struct fragment *frag)
1178 {
1179         char *buf = desc->buffer;
1180         const char *patch = frag->patch;
1181         int offset, size = frag->size;
1182         char *old = xmalloc(size);
1183         char *new = xmalloc(size);
1184         int oldsize = 0, newsize = 0;
1185
1186         while (size > 0) {
1187                 int len = linelen(patch, size);
1188                 int plen;
1189
1190                 if (!len)
1191                         break;
1192
1193                 /*
1194                  * "plen" is how much of the line we should use for
1195                  * the actual patch data. Normally we just remove the
1196                  * first character on the line, but if the line is
1197                  * followed by "\ No newline", then we also remove the
1198                  * last one (which is the newline, of course).
1199                  */
1200                 plen = len-1;
1201                 if (len < size && patch[len] == '\\')
1202                         plen--;
1203                 switch (*patch) {
1204                 case ' ':
1205                 case '-':
1206                         memcpy(old + oldsize, patch + 1, plen);
1207                         oldsize += plen;
1208                         if (*patch == '-')
1209                                 break;
1210                 /* Fall-through for ' ' */
1211                 case '+':
1212                         if (*patch != '+' || !no_add)
1213                                 newsize += apply_line(new + newsize, patch,
1214                                                       plen);
1215                         break;
1216                 case '@': case '\\':
1217                         /* Ignore it, we already handled it */
1218                         break;
1219                 default:
1220                         return -1;
1221                 }
1222                 patch += len;
1223                 size -= len;
1224         }
1225
1226         offset = find_offset(buf, desc->size, old, oldsize, frag->newpos);
1227         if (offset >= 0) {
1228                 int diff = newsize - oldsize;
1229                 unsigned long size = desc->size + diff;
1230                 unsigned long alloc = desc->alloc;
1231
1232                 if (size > alloc) {
1233                         alloc = size + 8192;
1234                         desc->alloc = alloc;
1235                         buf = xrealloc(buf, alloc);
1236                         desc->buffer = buf;
1237                 }
1238                 desc->size = size;
1239                 memmove(buf + offset + newsize, buf + offset + oldsize, size - offset - newsize);
1240                 memcpy(buf + offset, new, newsize);
1241                 offset = 0;
1242         }
1243
1244         free(old);
1245         free(new);
1246         return offset;
1247 }
1248
1249 static int apply_fragments(struct buffer_desc *desc, struct patch *patch)
1250 {
1251         struct fragment *frag = patch->fragments;
1252         const char *name = patch->old_name ? patch->old_name : patch->new_name;
1253
1254         if (patch->is_binary) {
1255                 unsigned char sha1[20];
1256
1257                 if (!allow_binary_replacement)
1258                         return error("cannot apply binary patch to '%s' "
1259                                      "without --allow-binary-replacement",
1260                                      name);
1261
1262                 /* For safety, we require patch index line to contain
1263                  * full 40-byte textual SHA1 for old and new, at least for now.
1264                  */
1265                 if (strlen(patch->old_sha1_prefix) != 40 ||
1266                     strlen(patch->new_sha1_prefix) != 40 ||
1267                     get_sha1_hex(patch->old_sha1_prefix, sha1) ||
1268                     get_sha1_hex(patch->new_sha1_prefix, sha1))
1269                         return error("cannot apply binary patch to '%s' "
1270                                      "without full index line", name);
1271
1272                 if (patch->old_name) {
1273                         unsigned char hdr[50];
1274                         int hdrlen;
1275
1276                         /* See if the old one matches what the patch
1277                          * applies to.
1278                          */
1279                         write_sha1_file_prepare(desc->buffer, desc->size,
1280                                                 "blob", sha1, hdr, &hdrlen);
1281                         if (strcmp(sha1_to_hex(sha1), patch->old_sha1_prefix))
1282                                 return error("the patch applies to '%s' (%s), "
1283                                              "which does not match the "
1284                                              "current contents.",
1285                                              name, sha1_to_hex(sha1));
1286                 }
1287                 else {
1288                         /* Otherwise, the old one must be empty. */
1289                         if (desc->size)
1290                                 return error("the patch applies to an empty "
1291                                              "'%s' but it is not empty", name);
1292                 }
1293
1294                 /* For now, we do not record post-image data in the patch,
1295                  * and require the object already present in the recipient's
1296                  * object database.
1297                  */
1298                 if (desc->buffer) {
1299                         free(desc->buffer);
1300                         desc->alloc = desc->size = 0;
1301                 }
1302                 get_sha1_hex(patch->new_sha1_prefix, sha1);
1303
1304                 if (memcmp(sha1, null_sha1, 20)) {
1305                         char type[10];
1306                         unsigned long size;
1307
1308                         desc->buffer = read_sha1_file(sha1, type, &size);
1309                         if (!desc->buffer)
1310                                 return error("the necessary postimage %s for "
1311                                              "'%s' does not exist",
1312                                              patch->new_sha1_prefix, name);
1313                         desc->alloc = desc->size = size;
1314                 }
1315
1316                 return 0;
1317         }
1318
1319         while (frag) {
1320                 if (apply_one_fragment(desc, frag) < 0)
1321                         return error("patch failed: %s:%ld",
1322                                      name, frag->oldpos);
1323                 frag = frag->next;
1324         }
1325         return 0;
1326 }
1327
1328 static int apply_data(struct patch *patch, struct stat *st)
1329 {
1330         char *buf;
1331         unsigned long size, alloc;
1332         struct buffer_desc desc;
1333
1334         size = 0;
1335         alloc = 0;
1336         buf = NULL;
1337         if (patch->old_name) {
1338                 size = st->st_size;
1339                 alloc = size + 8192;
1340                 buf = xmalloc(alloc);
1341                 if (read_old_data(st, patch->old_name, buf, alloc) != size)
1342                         return error("read of %s failed", patch->old_name);
1343         }
1344
1345         desc.size = size;
1346         desc.alloc = alloc;
1347         desc.buffer = buf;
1348         if (apply_fragments(&desc, patch) < 0)
1349                 return -1;
1350         patch->result = desc.buffer;
1351         patch->resultsize = desc.size;
1352
1353         if (patch->is_delete && patch->resultsize)
1354                 return error("removal patch leaves file contents");
1355
1356         return 0;
1357 }
1358
1359 static int check_patch(struct patch *patch)
1360 {
1361         struct stat st;
1362         const char *old_name = patch->old_name;
1363         const char *new_name = patch->new_name;
1364         const char *name = old_name ? old_name : new_name;
1365
1366         if (old_name) {
1367                 int changed;
1368                 int stat_ret = lstat(old_name, &st);
1369
1370                 if (check_index) {
1371                         int pos = cache_name_pos(old_name, strlen(old_name));
1372                         if (pos < 0)
1373                                 return error("%s: does not exist in index",
1374                                              old_name);
1375                         if (stat_ret < 0) {
1376                                 struct checkout costate;
1377                                 if (errno != ENOENT)
1378                                         return error("%s: %s", old_name,
1379                                                      strerror(errno));
1380                                 /* checkout */
1381                                 costate.base_dir = "";
1382                                 costate.base_dir_len = 0;
1383                                 costate.force = 0;
1384                                 costate.quiet = 0;
1385                                 costate.not_new = 0;
1386                                 costate.refresh_cache = 1;
1387                                 if (checkout_entry(active_cache[pos],
1388                                                    &costate) ||
1389                                     lstat(old_name, &st))
1390                                         return -1;
1391                         }
1392
1393                         changed = ce_match_stat(active_cache[pos], &st);
1394                         if (changed)
1395                                 return error("%s: does not match index",
1396                                              old_name);
1397                 }
1398                 else if (stat_ret < 0)
1399                         return error("%s: %s", old_name, strerror(errno));
1400
1401                 if (patch->is_new < 0)
1402                         patch->is_new = 0;
1403                 st.st_mode = ntohl(create_ce_mode(st.st_mode));
1404                 if (!patch->old_mode)
1405                         patch->old_mode = st.st_mode;
1406                 if ((st.st_mode ^ patch->old_mode) & S_IFMT)
1407                         return error("%s: wrong type", old_name);
1408                 if (st.st_mode != patch->old_mode)
1409                         fprintf(stderr, "warning: %s has type %o, expected %o\n",
1410                                 old_name, st.st_mode, patch->old_mode);
1411         }
1412
1413         if (new_name && (patch->is_new | patch->is_rename | patch->is_copy)) {
1414                 if (check_index && cache_name_pos(new_name, strlen(new_name)) >= 0)
1415                         return error("%s: already exists in index", new_name);
1416                 if (!lstat(new_name, &st))
1417                         return error("%s: already exists in working directory", new_name);
1418                 if (errno != ENOENT)
1419                         return error("%s: %s", new_name, strerror(errno));
1420                 if (!patch->new_mode) {
1421                         if (patch->is_new)
1422                                 patch->new_mode = S_IFREG | 0644;
1423                         else
1424                                 patch->new_mode = patch->old_mode;
1425                 }
1426         }
1427
1428         if (new_name && old_name) {
1429                 int same = !strcmp(old_name, new_name);
1430                 if (!patch->new_mode)
1431                         patch->new_mode = patch->old_mode;
1432                 if ((patch->old_mode ^ patch->new_mode) & S_IFMT)
1433                         return error("new mode (%o) of %s does not match old mode (%o)%s%s",
1434                                 patch->new_mode, new_name, patch->old_mode,
1435                                 same ? "" : " of ", same ? "" : old_name);
1436         }       
1437
1438         if (apply_data(patch, &st) < 0)
1439                 return error("%s: patch does not apply", name);
1440         return 0;
1441 }
1442
1443 static int check_patch_list(struct patch *patch)
1444 {
1445         int error = 0;
1446
1447         for (;patch ; patch = patch->next)
1448                 error |= check_patch(patch);
1449         return error;
1450 }
1451
1452 static inline int is_null_sha1(const unsigned char *sha1)
1453 {
1454         return !memcmp(sha1, null_sha1, 20);
1455 }
1456
1457 static void show_index_list(struct patch *list)
1458 {
1459         struct patch *patch;
1460
1461         /* Once we start supporting the reverse patch, it may be
1462          * worth showing the new sha1 prefix, but until then...
1463          */
1464         for (patch = list; patch; patch = patch->next) {
1465                 const unsigned char *sha1_ptr;
1466                 unsigned char sha1[20];
1467                 const char *name;
1468
1469                 name = patch->old_name ? patch->old_name : patch->new_name;
1470                 if (patch->is_new)
1471                         sha1_ptr = null_sha1;
1472                 else if (get_sha1(patch->old_sha1_prefix, sha1))
1473                         die("sha1 information is lacking or useless (%s).",
1474                             name);
1475                 else
1476                         sha1_ptr = sha1;
1477
1478                 printf("%06o %s ",patch->old_mode, sha1_to_hex(sha1_ptr));
1479                 if (line_termination && quote_c_style(name, NULL, NULL, 0))
1480                         quote_c_style(name, NULL, stdout, 0);
1481                 else
1482                         fputs(name, stdout);
1483                 putchar(line_termination);
1484         }
1485 }
1486
1487 static void stat_patch_list(struct patch *patch)
1488 {
1489         int files, adds, dels;
1490
1491         for (files = adds = dels = 0 ; patch ; patch = patch->next) {
1492                 files++;
1493                 adds += patch->lines_added;
1494                 dels += patch->lines_deleted;
1495                 show_stats(patch);
1496         }
1497
1498         printf(" %d files changed, %d insertions(+), %d deletions(-)\n", files, adds, dels);
1499 }
1500
1501 static void numstat_patch_list(struct patch *patch)
1502 {
1503         for ( ; patch; patch = patch->next) {
1504                 const char *name;
1505                 name = patch->old_name ? patch->old_name : patch->new_name;
1506                 printf("%d\t%d\t", patch->lines_added, patch->lines_deleted);
1507                 if (line_termination && quote_c_style(name, NULL, NULL, 0))
1508                         quote_c_style(name, NULL, stdout, 0);
1509                 else
1510                         fputs(name, stdout);
1511                 putchar('\n');
1512         }
1513 }
1514
1515 static void show_file_mode_name(const char *newdelete, unsigned int mode, const char *name)
1516 {
1517         if (mode)
1518                 printf(" %s mode %06o %s\n", newdelete, mode, name);
1519         else
1520                 printf(" %s %s\n", newdelete, name);
1521 }
1522
1523 static void show_mode_change(struct patch *p, int show_name)
1524 {
1525         if (p->old_mode && p->new_mode && p->old_mode != p->new_mode) {
1526                 if (show_name)
1527                         printf(" mode change %06o => %06o %s\n",
1528                                p->old_mode, p->new_mode, p->new_name);
1529                 else
1530                         printf(" mode change %06o => %06o\n",
1531                                p->old_mode, p->new_mode);
1532         }
1533 }
1534
1535 static void show_rename_copy(struct patch *p)
1536 {
1537         const char *renamecopy = p->is_rename ? "rename" : "copy";
1538         const char *old, *new;
1539
1540         /* Find common prefix */
1541         old = p->old_name;
1542         new = p->new_name;
1543         while (1) {
1544                 const char *slash_old, *slash_new;
1545                 slash_old = strchr(old, '/');
1546                 slash_new = strchr(new, '/');
1547                 if (!slash_old ||
1548                     !slash_new ||
1549                     slash_old - old != slash_new - new ||
1550                     memcmp(old, new, slash_new - new))
1551                         break;
1552                 old = slash_old + 1;
1553                 new = slash_new + 1;
1554         }
1555         /* p->old_name thru old is the common prefix, and old and new
1556          * through the end of names are renames
1557          */
1558         if (old != p->old_name)
1559                 printf(" %s %.*s{%s => %s} (%d%%)\n", renamecopy,
1560                        (int)(old - p->old_name), p->old_name,
1561                        old, new, p->score);
1562         else
1563                 printf(" %s %s => %s (%d%%)\n", renamecopy,
1564                        p->old_name, p->new_name, p->score);
1565         show_mode_change(p, 0);
1566 }
1567
1568 static void summary_patch_list(struct patch *patch)
1569 {
1570         struct patch *p;
1571
1572         for (p = patch; p; p = p->next) {
1573                 if (p->is_new)
1574                         show_file_mode_name("create", p->new_mode, p->new_name);
1575                 else if (p->is_delete)
1576                         show_file_mode_name("delete", p->old_mode, p->old_name);
1577                 else {
1578                         if (p->is_rename || p->is_copy)
1579                                 show_rename_copy(p);
1580                         else {
1581                                 if (p->score) {
1582                                         printf(" rewrite %s (%d%%)\n",
1583                                                p->new_name, p->score);
1584                                         show_mode_change(p, 0);
1585                                 }
1586                                 else
1587                                         show_mode_change(p, 1);
1588                         }
1589                 }
1590         }
1591 }
1592
1593 static void patch_stats(struct patch *patch)
1594 {
1595         int lines = patch->lines_added + patch->lines_deleted;
1596
1597         if (lines > max_change)
1598                 max_change = lines;
1599         if (patch->old_name) {
1600                 int len = quote_c_style(patch->old_name, NULL, NULL, 0);
1601                 if (!len)
1602                         len = strlen(patch->old_name);
1603                 if (len > max_len)
1604                         max_len = len;
1605         }
1606         if (patch->new_name) {
1607                 int len = quote_c_style(patch->new_name, NULL, NULL, 0);
1608                 if (!len)
1609                         len = strlen(patch->new_name);
1610                 if (len > max_len)
1611                         max_len = len;
1612         }
1613 }
1614
1615 static void remove_file(struct patch *patch)
1616 {
1617         if (write_index) {
1618                 if (remove_file_from_cache(patch->old_name) < 0)
1619                         die("unable to remove %s from index", patch->old_name);
1620         }
1621         unlink(patch->old_name);
1622 }
1623
1624 static void add_index_file(const char *path, unsigned mode, void *buf, unsigned long size)
1625 {
1626         struct stat st;
1627         struct cache_entry *ce;
1628         int namelen = strlen(path);
1629         unsigned ce_size = cache_entry_size(namelen);
1630
1631         if (!write_index)
1632                 return;
1633
1634         ce = xmalloc(ce_size);
1635         memset(ce, 0, ce_size);
1636         memcpy(ce->name, path, namelen);
1637         ce->ce_mode = create_ce_mode(mode);
1638         ce->ce_flags = htons(namelen);
1639         if (lstat(path, &st) < 0)
1640                 die("unable to stat newly created file %s", path);
1641         fill_stat_cache_info(ce, &st);
1642         if (write_sha1_file(buf, size, "blob", ce->sha1) < 0)
1643                 die("unable to create backing store for newly created file %s", path);
1644         if (add_cache_entry(ce, ADD_CACHE_OK_TO_ADD) < 0)
1645                 die("unable to add cache entry for %s", path);
1646 }
1647
1648 static int try_create_file(const char *path, unsigned int mode, const char *buf, unsigned long size)
1649 {
1650         int fd;
1651
1652         if (S_ISLNK(mode))
1653                 return symlink(buf, path);
1654         fd = open(path, O_CREAT | O_EXCL | O_WRONLY, (mode & 0100) ? 0777 : 0666);
1655         if (fd < 0)
1656                 return -1;
1657         while (size) {
1658                 int written = xwrite(fd, buf, size);
1659                 if (written < 0)
1660                         die("writing file %s: %s", path, strerror(errno));
1661                 if (!written)
1662                         die("out of space writing file %s", path);
1663                 buf += written;
1664                 size -= written;
1665         }
1666         if (close(fd) < 0)
1667                 die("closing file %s: %s", path, strerror(errno));
1668         return 0;
1669 }
1670
1671 /*
1672  * We optimistically assume that the directories exist,
1673  * which is true 99% of the time anyway. If they don't,
1674  * we create them and try again.
1675  */
1676 static void create_one_file(char *path, unsigned mode, const char *buf, unsigned long size)
1677 {
1678         if (!try_create_file(path, mode, buf, size))
1679                 return;
1680
1681         if (errno == ENOENT) {
1682                 if (safe_create_leading_directories(path))
1683                         return;
1684                 if (!try_create_file(path, mode, buf, size))
1685                         return;
1686         }
1687
1688         if (errno == EEXIST) {
1689                 unsigned int nr = getpid();
1690
1691                 for (;;) {
1692                         const char *newpath;
1693                         newpath = mkpath("%s~%u", path, nr);
1694                         if (!try_create_file(newpath, mode, buf, size)) {
1695                                 if (!rename(newpath, path))
1696                                         return;
1697                                 unlink(newpath);
1698                                 break;
1699                         }
1700                         if (errno != EEXIST)
1701                                 break;
1702                         ++nr;
1703                 }
1704         }
1705         die("unable to write file %s mode %o", path, mode);
1706 }
1707
1708 static void create_file(struct patch *patch)
1709 {
1710         char *path = patch->new_name;
1711         unsigned mode = patch->new_mode;
1712         unsigned long size = patch->resultsize;
1713         char *buf = patch->result;
1714
1715         if (!mode)
1716                 mode = S_IFREG | 0644;
1717         create_one_file(path, mode, buf, size); 
1718         add_index_file(path, mode, buf, size);
1719 }
1720
1721 static void write_out_one_result(struct patch *patch)
1722 {
1723         if (patch->is_delete > 0) {
1724                 remove_file(patch);
1725                 return;
1726         }
1727         if (patch->is_new > 0 || patch->is_copy) {
1728                 create_file(patch);
1729                 return;
1730         }
1731         /*
1732          * Rename or modification boils down to the same
1733          * thing: remove the old, write the new
1734          */
1735         remove_file(patch);
1736         create_file(patch);
1737 }
1738
1739 static void write_out_results(struct patch *list, int skipped_patch)
1740 {
1741         if (!list && !skipped_patch)
1742                 die("No changes");
1743
1744         while (list) {
1745                 write_out_one_result(list);
1746                 list = list->next;
1747         }
1748 }
1749
1750 static struct cache_file cache_file;
1751
1752 static struct excludes {
1753         struct excludes *next;
1754         const char *path;
1755 } *excludes;
1756
1757 static int use_patch(struct patch *p)
1758 {
1759         const char *pathname = p->new_name ? p->new_name : p->old_name;
1760         struct excludes *x = excludes;
1761         while (x) {
1762                 if (fnmatch(x->path, pathname, 0) == 0)
1763                         return 0;
1764                 x = x->next;
1765         }
1766         if (0 < prefix_length) {
1767                 int pathlen = strlen(pathname);
1768                 if (pathlen <= prefix_length ||
1769                     memcmp(prefix, pathname, prefix_length))
1770                         return 0;
1771         }
1772         return 1;
1773 }
1774
1775 static int apply_patch(int fd, const char *filename)
1776 {
1777         int newfd;
1778         unsigned long offset, size;
1779         char *buffer = read_patch_file(fd, &size);
1780         struct patch *list = NULL, **listp = &list;
1781         int skipped_patch = 0;
1782
1783         patch_input_file = filename;
1784         if (!buffer)
1785                 return -1;
1786         offset = 0;
1787         while (size > 0) {
1788                 struct patch *patch;
1789                 int nr;
1790
1791                 patch = xmalloc(sizeof(*patch));
1792                 memset(patch, 0, sizeof(*patch));
1793                 nr = parse_chunk(buffer + offset, size, patch);
1794                 if (nr < 0)
1795                         break;
1796                 if (use_patch(patch)) {
1797                         patch_stats(patch);
1798                         *listp = patch;
1799                         listp = &patch->next;
1800                 } else {
1801                         /* perhaps free it a bit better? */
1802                         free(patch);
1803                         skipped_patch++;
1804                 }
1805                 offset += nr;
1806                 size -= nr;
1807         }
1808
1809         newfd = -1;
1810         if (whitespace_error && (new_whitespace == error_on_whitespace))
1811                 apply = 0;
1812
1813         write_index = check_index && apply;
1814         if (write_index)
1815                 newfd = hold_index_file_for_update(&cache_file, get_index_file());
1816         if (check_index) {
1817                 if (read_cache() < 0)
1818                         die("unable to read index file");
1819         }
1820
1821         if ((check || apply) && check_patch_list(list) < 0)
1822                 exit(1);
1823
1824         if (apply)
1825                 write_out_results(list, skipped_patch);
1826
1827         if (write_index) {
1828                 if (write_cache(newfd, active_cache, active_nr) ||
1829                     commit_index_file(&cache_file))
1830                         die("Unable to write new cachefile");
1831         }
1832
1833         if (show_index_info)
1834                 show_index_list(list);
1835
1836         if (diffstat)
1837                 stat_patch_list(list);
1838
1839         if (numstat)
1840                 numstat_patch_list(list);
1841
1842         if (summary)
1843                 summary_patch_list(list);
1844
1845         free(buffer);
1846         return 0;
1847 }
1848
1849 static int git_apply_config(const char *var, const char *value)
1850 {
1851         if (!strcmp(var, "apply.whitespace")) {
1852                 apply_default_whitespace = strdup(value);
1853                 return 0;
1854         }
1855         return git_default_config(var, value);
1856 }
1857
1858
1859 int main(int argc, char **argv)
1860 {
1861         int i;
1862         int read_stdin = 1;
1863         const char *whitespace_option = NULL;
1864
1865         for (i = 1; i < argc; i++) {
1866                 const char *arg = argv[i];
1867                 int fd;
1868
1869                 if (!strcmp(arg, "-")) {
1870                         apply_patch(0, "<stdin>");
1871                         read_stdin = 0;
1872                         continue;
1873                 }
1874                 if (!strncmp(arg, "--exclude=", 10)) {
1875                         struct excludes *x = xmalloc(sizeof(*x));
1876                         x->path = arg + 10;
1877                         x->next = excludes;
1878                         excludes = x;
1879                         continue;
1880                 }
1881                 if (!strncmp(arg, "-p", 2)) {
1882                         p_value = atoi(arg + 2);
1883                         continue;
1884                 }
1885                 if (!strcmp(arg, "--no-add")) {
1886                         no_add = 1;
1887                         continue;
1888                 }
1889                 if (!strcmp(arg, "--stat")) {
1890                         apply = 0;
1891                         diffstat = 1;
1892                         continue;
1893                 }
1894                 if (!strcmp(arg, "--allow-binary-replacement")) {
1895                         allow_binary_replacement = 1;
1896                         continue;
1897                 }
1898                 if (!strcmp(arg, "--numstat")) {
1899                         apply = 0;
1900                         numstat = 1;
1901                         continue;
1902                 }
1903                 if (!strcmp(arg, "--summary")) {
1904                         apply = 0;
1905                         summary = 1;
1906                         continue;
1907                 }
1908                 if (!strcmp(arg, "--check")) {
1909                         apply = 0;
1910                         check = 1;
1911                         continue;
1912                 }
1913                 if (!strcmp(arg, "--index")) {
1914                         check_index = 1;
1915                         continue;
1916                 }
1917                 if (!strcmp(arg, "--apply")) {
1918                         apply = 1;
1919                         continue;
1920                 }
1921                 if (!strcmp(arg, "--index-info")) {
1922                         apply = 0;
1923                         show_index_info = 1;
1924                         continue;
1925                 }
1926                 if (!strcmp(arg, "-z")) {
1927                         line_termination = 0;
1928                         continue;
1929                 }
1930                 if (!strncmp(arg, "--whitespace=", 13)) {
1931                         whitespace_option = arg + 13;
1932                         parse_whitespace_option(arg + 13);
1933                         continue;
1934                 }
1935
1936                 if (check_index && prefix_length < 0) {
1937                         prefix = setup_git_directory();
1938                         prefix_length = prefix ? strlen(prefix) : 0;
1939                         git_config(git_apply_config);
1940                         if (!whitespace_option && apply_default_whitespace)
1941                                 parse_whitespace_option(apply_default_whitespace);
1942                 }
1943                 if (0 < prefix_length)
1944                         arg = prefix_filename(prefix, prefix_length, arg);
1945
1946                 fd = open(arg, O_RDONLY);
1947                 if (fd < 0)
1948                         usage(apply_usage);
1949                 read_stdin = 0;
1950                 apply_patch(fd, arg);
1951                 close(fd);
1952         }
1953         if (read_stdin)
1954                 apply_patch(0, "<stdin>");
1955         if (whitespace_error) {
1956                 if (squelch_whitespace_errors &&
1957                     squelch_whitespace_errors < whitespace_error) {
1958                         int squelched =
1959                                 whitespace_error - squelch_whitespace_errors;
1960                         fprintf(stderr, "warning: squelched %d whitespace error%s\n",
1961                                 squelched,
1962                                 squelched == 1 ? "" : "s");
1963                 }
1964                 if (new_whitespace == error_on_whitespace)
1965                         die("%d line%s add%s trailing whitespaces.",
1966                             whitespace_error,
1967                             whitespace_error == 1 ? "" : "s",
1968                             whitespace_error == 1 ? "s" : "");
1969                 if (applied_after_stripping)
1970                         fprintf(stderr, "warning: %d line%s applied after"
1971                                 " stripping trailing whitespaces.\n",
1972                                 applied_after_stripping,
1973                                 applied_after_stripping == 1 ? "" : "s");
1974                 else if (whitespace_error)
1975                         fprintf(stderr, "warning: %d line%s add%s trailing"
1976                                 " whitespaces.\n",
1977                                 whitespace_error,
1978                                 whitespace_error == 1 ? "" : "s",
1979                                 whitespace_error == 1 ? "s" : "");
1980         }
1981         return 0;
1982 }