Merge branch 'maint'
[git] / builtin-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 "cache.h"
10 #include "cache-tree.h"
11 #include "quote.h"
12 #include "blob.h"
13 #include "delta.h"
14 #include "builtin.h"
15 #include "string-list.h"
16 #include "dir.h"
17
18 /*
19  *  --check turns on checking that the working tree matches the
20  *    files that are being modified, but doesn't apply the patch
21  *  --stat does just a diffstat, and doesn't actually apply
22  *  --numstat does numeric diffstat, and doesn't actually apply
23  *  --index-info shows the old and new index info for paths if available.
24  *  --index updates the cache as well.
25  *  --cached updates only the cache without ever touching the working tree.
26  */
27 static const char *prefix;
28 static int prefix_length = -1;
29 static int newfd = -1;
30
31 static int unidiff_zero;
32 static int p_value = 1;
33 static int p_value_known;
34 static int check_index;
35 static int update_index;
36 static int cached;
37 static int diffstat;
38 static int numstat;
39 static int summary;
40 static int check;
41 static int apply = 1;
42 static int apply_in_reverse;
43 static int apply_with_reject;
44 static int apply_verbosely;
45 static int no_add;
46 static const char *fake_ancestor;
47 static int line_termination = '\n';
48 static unsigned long p_context = ULONG_MAX;
49 static const char apply_usage[] =
50 "git apply [--stat] [--numstat] [--summary] [--check] [--index] [--cached] [--apply] [--no-add] [--index-info] [--allow-binary-replacement] [--reverse] [--reject] [--verbose] [-z] [-pNUM] [-CNUM] [--whitespace=<nowarn|warn|fix|error|error-all>] <patch>...";
51
52 static enum ws_error_action {
53         nowarn_ws_error,
54         warn_on_ws_error,
55         die_on_ws_error,
56         correct_ws_error,
57 } ws_error_action = warn_on_ws_error;
58 static int whitespace_error;
59 static int squelch_whitespace_errors = 5;
60 static int applied_after_fixing_ws;
61 static const char *patch_input_file;
62 static const char *root;
63 static int root_len;
64
65 static void parse_whitespace_option(const char *option)
66 {
67         if (!option) {
68                 ws_error_action = warn_on_ws_error;
69                 return;
70         }
71         if (!strcmp(option, "warn")) {
72                 ws_error_action = warn_on_ws_error;
73                 return;
74         }
75         if (!strcmp(option, "nowarn")) {
76                 ws_error_action = nowarn_ws_error;
77                 return;
78         }
79         if (!strcmp(option, "error")) {
80                 ws_error_action = die_on_ws_error;
81                 return;
82         }
83         if (!strcmp(option, "error-all")) {
84                 ws_error_action = die_on_ws_error;
85                 squelch_whitespace_errors = 0;
86                 return;
87         }
88         if (!strcmp(option, "strip") || !strcmp(option, "fix")) {
89                 ws_error_action = correct_ws_error;
90                 return;
91         }
92         die("unrecognized whitespace option '%s'", option);
93 }
94
95 static void set_default_whitespace_mode(const char *whitespace_option)
96 {
97         if (!whitespace_option && !apply_default_whitespace)
98                 ws_error_action = (apply ? warn_on_ws_error : nowarn_ws_error);
99 }
100
101 /*
102  * For "diff-stat" like behaviour, we keep track of the biggest change
103  * we've seen, and the longest filename. That allows us to do simple
104  * scaling.
105  */
106 static int max_change, max_len;
107
108 /*
109  * Various "current state", notably line numbers and what
110  * file (and how) we're patching right now.. The "is_xxxx"
111  * things are flags, where -1 means "don't know yet".
112  */
113 static int linenr = 1;
114
115 /*
116  * This represents one "hunk" from a patch, starting with
117  * "@@ -oldpos,oldlines +newpos,newlines @@" marker.  The
118  * patch text is pointed at by patch, and its byte length
119  * is stored in size.  leading and trailing are the number
120  * of context lines.
121  */
122 struct fragment {
123         unsigned long leading, trailing;
124         unsigned long oldpos, oldlines;
125         unsigned long newpos, newlines;
126         const char *patch;
127         int size;
128         int rejected;
129         struct fragment *next;
130 };
131
132 /*
133  * When dealing with a binary patch, we reuse "leading" field
134  * to store the type of the binary hunk, either deflated "delta"
135  * or deflated "literal".
136  */
137 #define binary_patch_method leading
138 #define BINARY_DELTA_DEFLATED   1
139 #define BINARY_LITERAL_DEFLATED 2
140
141 /*
142  * This represents a "patch" to a file, both metainfo changes
143  * such as creation/deletion, filemode and content changes represented
144  * as a series of fragments.
145  */
146 struct patch {
147         char *new_name, *old_name, *def_name;
148         unsigned int old_mode, new_mode;
149         int is_new, is_delete;  /* -1 = unknown, 0 = false, 1 = true */
150         int rejected;
151         unsigned ws_rule;
152         unsigned long deflate_origlen;
153         int lines_added, lines_deleted;
154         int score;
155         unsigned int is_toplevel_relative:1;
156         unsigned int inaccurate_eof:1;
157         unsigned int is_binary:1;
158         unsigned int is_copy:1;
159         unsigned int is_rename:1;
160         unsigned int recount:1;
161         struct fragment *fragments;
162         char *result;
163         size_t resultsize;
164         char old_sha1_prefix[41];
165         char new_sha1_prefix[41];
166         struct patch *next;
167 };
168
169 /*
170  * A line in a file, len-bytes long (includes the terminating LF,
171  * except for an incomplete line at the end if the file ends with
172  * one), and its contents hashes to 'hash'.
173  */
174 struct line {
175         size_t len;
176         unsigned hash : 24;
177         unsigned flag : 8;
178 #define LINE_COMMON     1
179 };
180
181 /*
182  * This represents a "file", which is an array of "lines".
183  */
184 struct image {
185         char *buf;
186         size_t len;
187         size_t nr;
188         size_t alloc;
189         struct line *line_allocated;
190         struct line *line;
191 };
192
193 /*
194  * Records filenames that have been touched, in order to handle
195  * the case where more than one patches touch the same file.
196  */
197
198 static struct string_list fn_table;
199
200 static uint32_t hash_line(const char *cp, size_t len)
201 {
202         size_t i;
203         uint32_t h;
204         for (i = 0, h = 0; i < len; i++) {
205                 if (!isspace(cp[i])) {
206                         h = h * 3 + (cp[i] & 0xff);
207                 }
208         }
209         return h;
210 }
211
212 static void add_line_info(struct image *img, const char *bol, size_t len, unsigned flag)
213 {
214         ALLOC_GROW(img->line_allocated, img->nr + 1, img->alloc);
215         img->line_allocated[img->nr].len = len;
216         img->line_allocated[img->nr].hash = hash_line(bol, len);
217         img->line_allocated[img->nr].flag = flag;
218         img->nr++;
219 }
220
221 static void prepare_image(struct image *image, char *buf, size_t len,
222                           int prepare_linetable)
223 {
224         const char *cp, *ep;
225
226         memset(image, 0, sizeof(*image));
227         image->buf = buf;
228         image->len = len;
229
230         if (!prepare_linetable)
231                 return;
232
233         ep = image->buf + image->len;
234         cp = image->buf;
235         while (cp < ep) {
236                 const char *next;
237                 for (next = cp; next < ep && *next != '\n'; next++)
238                         ;
239                 if (next < ep)
240                         next++;
241                 add_line_info(image, cp, next - cp, 0);
242                 cp = next;
243         }
244         image->line = image->line_allocated;
245 }
246
247 static void clear_image(struct image *image)
248 {
249         free(image->buf);
250         image->buf = NULL;
251         image->len = 0;
252 }
253
254 static void say_patch_name(FILE *output, const char *pre,
255                            struct patch *patch, const char *post)
256 {
257         fputs(pre, output);
258         if (patch->old_name && patch->new_name &&
259             strcmp(patch->old_name, patch->new_name)) {
260                 quote_c_style(patch->old_name, NULL, output, 0);
261                 fputs(" => ", output);
262                 quote_c_style(patch->new_name, NULL, output, 0);
263         } else {
264                 const char *n = patch->new_name;
265                 if (!n)
266                         n = patch->old_name;
267                 quote_c_style(n, NULL, output, 0);
268         }
269         fputs(post, output);
270 }
271
272 #define CHUNKSIZE (8192)
273 #define SLOP (16)
274
275 static void read_patch_file(struct strbuf *sb, int fd)
276 {
277         if (strbuf_read(sb, fd, 0) < 0)
278                 die("git apply: read returned %s", strerror(errno));
279
280         /*
281          * Make sure that we have some slop in the buffer
282          * so that we can do speculative "memcmp" etc, and
283          * see to it that it is NUL-filled.
284          */
285         strbuf_grow(sb, SLOP);
286         memset(sb->buf + sb->len, 0, SLOP);
287 }
288
289 static unsigned long linelen(const char *buffer, unsigned long size)
290 {
291         unsigned long len = 0;
292         while (size--) {
293                 len++;
294                 if (*buffer++ == '\n')
295                         break;
296         }
297         return len;
298 }
299
300 static int is_dev_null(const char *str)
301 {
302         return !memcmp("/dev/null", str, 9) && isspace(str[9]);
303 }
304
305 #define TERM_SPACE      1
306 #define TERM_TAB        2
307
308 static int name_terminate(const char *name, int namelen, int c, int terminate)
309 {
310         if (c == ' ' && !(terminate & TERM_SPACE))
311                 return 0;
312         if (c == '\t' && !(terminate & TERM_TAB))
313                 return 0;
314
315         return 1;
316 }
317
318 static char *find_name(const char *line, char *def, int p_value, int terminate)
319 {
320         int len;
321         const char *start = line;
322
323         if (*line == '"') {
324                 struct strbuf name = STRBUF_INIT;
325
326                 /*
327                  * Proposed "new-style" GNU patch/diff format; see
328                  * http://marc.theaimsgroup.com/?l=git&m=112927316408690&w=2
329                  */
330                 if (!unquote_c_style(&name, line, NULL)) {
331                         char *cp;
332
333                         for (cp = name.buf; p_value; p_value--) {
334                                 cp = strchr(cp, '/');
335                                 if (!cp)
336                                         break;
337                                 cp++;
338                         }
339                         if (cp) {
340                                 /* name can later be freed, so we need
341                                  * to memmove, not just return cp
342                                  */
343                                 strbuf_remove(&name, 0, cp - name.buf);
344                                 free(def);
345                                 if (root)
346                                         strbuf_insert(&name, 0, root, root_len);
347                                 return strbuf_detach(&name, NULL);
348                         }
349                 }
350                 strbuf_release(&name);
351         }
352
353         for (;;) {
354                 char c = *line;
355
356                 if (isspace(c)) {
357                         if (c == '\n')
358                                 break;
359                         if (name_terminate(start, line-start, c, terminate))
360                                 break;
361                 }
362                 line++;
363                 if (c == '/' && !--p_value)
364                         start = line;
365         }
366         if (!start)
367                 return def;
368         len = line - start;
369         if (!len)
370                 return def;
371
372         /*
373          * Generally we prefer the shorter name, especially
374          * if the other one is just a variation of that with
375          * something else tacked on to the end (ie "file.orig"
376          * or "file~").
377          */
378         if (def) {
379                 int deflen = strlen(def);
380                 if (deflen < len && !strncmp(start, def, deflen))
381                         return def;
382                 free(def);
383         }
384
385         if (root) {
386                 char *ret = xmalloc(root_len + len + 1);
387                 strcpy(ret, root);
388                 memcpy(ret + root_len, start, len);
389                 ret[root_len + len] = '\0';
390                 return ret;
391         }
392
393         return xmemdupz(start, len);
394 }
395
396 static int count_slashes(const char *cp)
397 {
398         int cnt = 0;
399         char ch;
400
401         while ((ch = *cp++))
402                 if (ch == '/')
403                         cnt++;
404         return cnt;
405 }
406
407 /*
408  * Given the string after "--- " or "+++ ", guess the appropriate
409  * p_value for the given patch.
410  */
411 static int guess_p_value(const char *nameline)
412 {
413         char *name, *cp;
414         int val = -1;
415
416         if (is_dev_null(nameline))
417                 return -1;
418         name = find_name(nameline, NULL, 0, TERM_SPACE | TERM_TAB);
419         if (!name)
420                 return -1;
421         cp = strchr(name, '/');
422         if (!cp)
423                 val = 0;
424         else if (prefix) {
425                 /*
426                  * Does it begin with "a/$our-prefix" and such?  Then this is
427                  * very likely to apply to our directory.
428                  */
429                 if (!strncmp(name, prefix, prefix_length))
430                         val = count_slashes(prefix);
431                 else {
432                         cp++;
433                         if (!strncmp(cp, prefix, prefix_length))
434                                 val = count_slashes(prefix) + 1;
435                 }
436         }
437         free(name);
438         return val;
439 }
440
441 /*
442  * Get the name etc info from the ---/+++ lines of a traditional patch header
443  *
444  * FIXME! The end-of-filename heuristics are kind of screwy. For existing
445  * files, we can happily check the index for a match, but for creating a
446  * new file we should try to match whatever "patch" does. I have no idea.
447  */
448 static void parse_traditional_patch(const char *first, const char *second, struct patch *patch)
449 {
450         char *name;
451
452         first += 4;     /* skip "--- " */
453         second += 4;    /* skip "+++ " */
454         if (!p_value_known) {
455                 int p, q;
456                 p = guess_p_value(first);
457                 q = guess_p_value(second);
458                 if (p < 0) p = q;
459                 if (0 <= p && p == q) {
460                         p_value = p;
461                         p_value_known = 1;
462                 }
463         }
464         if (is_dev_null(first)) {
465                 patch->is_new = 1;
466                 patch->is_delete = 0;
467                 name = find_name(second, NULL, p_value, TERM_SPACE | TERM_TAB);
468                 patch->new_name = name;
469         } else if (is_dev_null(second)) {
470                 patch->is_new = 0;
471                 patch->is_delete = 1;
472                 name = find_name(first, NULL, p_value, TERM_SPACE | TERM_TAB);
473                 patch->old_name = name;
474         } else {
475                 name = find_name(first, NULL, p_value, TERM_SPACE | TERM_TAB);
476                 name = find_name(second, name, p_value, TERM_SPACE | TERM_TAB);
477                 patch->old_name = patch->new_name = name;
478         }
479         if (!name)
480                 die("unable to find filename in patch at line %d", linenr);
481 }
482
483 static int gitdiff_hdrend(const char *line, struct patch *patch)
484 {
485         return -1;
486 }
487
488 /*
489  * We're anal about diff header consistency, to make
490  * sure that we don't end up having strange ambiguous
491  * patches floating around.
492  *
493  * As a result, gitdiff_{old|new}name() will check
494  * their names against any previous information, just
495  * to make sure..
496  */
497 static char *gitdiff_verify_name(const char *line, int isnull, char *orig_name, const char *oldnew)
498 {
499         if (!orig_name && !isnull)
500                 return find_name(line, NULL, p_value, TERM_TAB);
501
502         if (orig_name) {
503                 int len;
504                 const char *name;
505                 char *another;
506                 name = orig_name;
507                 len = strlen(name);
508                 if (isnull)
509                         die("git apply: bad git-diff - expected /dev/null, got %s on line %d", name, linenr);
510                 another = find_name(line, NULL, p_value, TERM_TAB);
511                 if (!another || memcmp(another, name, len))
512                         die("git apply: bad git-diff - inconsistent %s filename on line %d", oldnew, linenr);
513                 free(another);
514                 return orig_name;
515         }
516         else {
517                 /* expect "/dev/null" */
518                 if (memcmp("/dev/null", line, 9) || line[9] != '\n')
519                         die("git apply: bad git-diff - expected /dev/null on line %d", linenr);
520                 return NULL;
521         }
522 }
523
524 static int gitdiff_oldname(const char *line, struct patch *patch)
525 {
526         patch->old_name = gitdiff_verify_name(line, patch->is_new, patch->old_name, "old");
527         return 0;
528 }
529
530 static int gitdiff_newname(const char *line, struct patch *patch)
531 {
532         patch->new_name = gitdiff_verify_name(line, patch->is_delete, patch->new_name, "new");
533         return 0;
534 }
535
536 static int gitdiff_oldmode(const char *line, struct patch *patch)
537 {
538         patch->old_mode = strtoul(line, NULL, 8);
539         return 0;
540 }
541
542 static int gitdiff_newmode(const char *line, struct patch *patch)
543 {
544         patch->new_mode = strtoul(line, NULL, 8);
545         return 0;
546 }
547
548 static int gitdiff_delete(const char *line, struct patch *patch)
549 {
550         patch->is_delete = 1;
551         patch->old_name = patch->def_name;
552         return gitdiff_oldmode(line, patch);
553 }
554
555 static int gitdiff_newfile(const char *line, struct patch *patch)
556 {
557         patch->is_new = 1;
558         patch->new_name = patch->def_name;
559         return gitdiff_newmode(line, patch);
560 }
561
562 static int gitdiff_copysrc(const char *line, struct patch *patch)
563 {
564         patch->is_copy = 1;
565         patch->old_name = find_name(line, NULL, 0, 0);
566         return 0;
567 }
568
569 static int gitdiff_copydst(const char *line, struct patch *patch)
570 {
571         patch->is_copy = 1;
572         patch->new_name = find_name(line, NULL, 0, 0);
573         return 0;
574 }
575
576 static int gitdiff_renamesrc(const char *line, struct patch *patch)
577 {
578         patch->is_rename = 1;
579         patch->old_name = find_name(line, NULL, 0, 0);
580         return 0;
581 }
582
583 static int gitdiff_renamedst(const char *line, struct patch *patch)
584 {
585         patch->is_rename = 1;
586         patch->new_name = find_name(line, NULL, 0, 0);
587         return 0;
588 }
589
590 static int gitdiff_similarity(const char *line, struct patch *patch)
591 {
592         if ((patch->score = strtoul(line, NULL, 10)) == ULONG_MAX)
593                 patch->score = 0;
594         return 0;
595 }
596
597 static int gitdiff_dissimilarity(const char *line, struct patch *patch)
598 {
599         if ((patch->score = strtoul(line, NULL, 10)) == ULONG_MAX)
600                 patch->score = 0;
601         return 0;
602 }
603
604 static int gitdiff_index(const char *line, struct patch *patch)
605 {
606         /*
607          * index line is N hexadecimal, "..", N hexadecimal,
608          * and optional space with octal mode.
609          */
610         const char *ptr, *eol;
611         int len;
612
613         ptr = strchr(line, '.');
614         if (!ptr || ptr[1] != '.' || 40 < ptr - line)
615                 return 0;
616         len = ptr - line;
617         memcpy(patch->old_sha1_prefix, line, len);
618         patch->old_sha1_prefix[len] = 0;
619
620         line = ptr + 2;
621         ptr = strchr(line, ' ');
622         eol = strchr(line, '\n');
623
624         if (!ptr || eol < ptr)
625                 ptr = eol;
626         len = ptr - line;
627
628         if (40 < len)
629                 return 0;
630         memcpy(patch->new_sha1_prefix, line, len);
631         patch->new_sha1_prefix[len] = 0;
632         if (*ptr == ' ')
633                 patch->new_mode = patch->old_mode = strtoul(ptr+1, NULL, 8);
634         return 0;
635 }
636
637 /*
638  * This is normal for a diff that doesn't change anything: we'll fall through
639  * into the next diff. Tell the parser to break out.
640  */
641 static int gitdiff_unrecognized(const char *line, struct patch *patch)
642 {
643         return -1;
644 }
645
646 static const char *stop_at_slash(const char *line, int llen)
647 {
648         int i;
649
650         for (i = 0; i < llen; i++) {
651                 int ch = line[i];
652                 if (ch == '/')
653                         return line + i;
654         }
655         return NULL;
656 }
657
658 /*
659  * This is to extract the same name that appears on "diff --git"
660  * line.  We do not find and return anything if it is a rename
661  * patch, and it is OK because we will find the name elsewhere.
662  * We need to reliably find name only when it is mode-change only,
663  * creation or deletion of an empty file.  In any of these cases,
664  * both sides are the same name under a/ and b/ respectively.
665  */
666 static char *git_header_name(char *line, int llen)
667 {
668         const char *name;
669         const char *second = NULL;
670         size_t len;
671
672         line += strlen("diff --git ");
673         llen -= strlen("diff --git ");
674
675         if (*line == '"') {
676                 const char *cp;
677                 struct strbuf first = STRBUF_INIT;
678                 struct strbuf sp = STRBUF_INIT;
679
680                 if (unquote_c_style(&first, line, &second))
681                         goto free_and_fail1;
682
683                 /* advance to the first slash */
684                 cp = stop_at_slash(first.buf, first.len);
685                 /* we do not accept absolute paths */
686                 if (!cp || cp == first.buf)
687                         goto free_and_fail1;
688                 strbuf_remove(&first, 0, cp + 1 - first.buf);
689
690                 /*
691                  * second points at one past closing dq of name.
692                  * find the second name.
693                  */
694                 while ((second < line + llen) && isspace(*second))
695                         second++;
696
697                 if (line + llen <= second)
698                         goto free_and_fail1;
699                 if (*second == '"') {
700                         if (unquote_c_style(&sp, second, NULL))
701                                 goto free_and_fail1;
702                         cp = stop_at_slash(sp.buf, sp.len);
703                         if (!cp || cp == sp.buf)
704                                 goto free_and_fail1;
705                         /* They must match, otherwise ignore */
706                         if (strcmp(cp + 1, first.buf))
707                                 goto free_and_fail1;
708                         strbuf_release(&sp);
709                         return strbuf_detach(&first, NULL);
710                 }
711
712                 /* unquoted second */
713                 cp = stop_at_slash(second, line + llen - second);
714                 if (!cp || cp == second)
715                         goto free_and_fail1;
716                 cp++;
717                 if (line + llen - cp != first.len + 1 ||
718                     memcmp(first.buf, cp, first.len))
719                         goto free_and_fail1;
720                 return strbuf_detach(&first, NULL);
721
722         free_and_fail1:
723                 strbuf_release(&first);
724                 strbuf_release(&sp);
725                 return NULL;
726         }
727
728         /* unquoted first name */
729         name = stop_at_slash(line, llen);
730         if (!name || name == line)
731                 return NULL;
732         name++;
733
734         /*
735          * since the first name is unquoted, a dq if exists must be
736          * the beginning of the second name.
737          */
738         for (second = name; second < line + llen; second++) {
739                 if (*second == '"') {
740                         struct strbuf sp = STRBUF_INIT;
741                         const char *np;
742
743                         if (unquote_c_style(&sp, second, NULL))
744                                 goto free_and_fail2;
745
746                         np = stop_at_slash(sp.buf, sp.len);
747                         if (!np || np == sp.buf)
748                                 goto free_and_fail2;
749                         np++;
750
751                         len = sp.buf + sp.len - np;
752                         if (len < second - name &&
753                             !strncmp(np, name, len) &&
754                             isspace(name[len])) {
755                                 /* Good */
756                                 strbuf_remove(&sp, 0, np - sp.buf);
757                                 return strbuf_detach(&sp, NULL);
758                         }
759
760                 free_and_fail2:
761                         strbuf_release(&sp);
762                         return NULL;
763                 }
764         }
765
766         /*
767          * Accept a name only if it shows up twice, exactly the same
768          * form.
769          */
770         for (len = 0 ; ; len++) {
771                 switch (name[len]) {
772                 default:
773                         continue;
774                 case '\n':
775                         return NULL;
776                 case '\t': case ' ':
777                         second = name+len;
778                         for (;;) {
779                                 char c = *second++;
780                                 if (c == '\n')
781                                         return NULL;
782                                 if (c == '/')
783                                         break;
784                         }
785                         if (second[len] == '\n' && !memcmp(name, second, len)) {
786                                 return xmemdupz(name, len);
787                         }
788                 }
789         }
790 }
791
792 /* Verify that we recognize the lines following a git header */
793 static int parse_git_header(char *line, int len, unsigned int size, struct patch *patch)
794 {
795         unsigned long offset;
796
797         /* A git diff has explicit new/delete information, so we don't guess */
798         patch->is_new = 0;
799         patch->is_delete = 0;
800
801         /*
802          * Some things may not have the old name in the
803          * rest of the headers anywhere (pure mode changes,
804          * or removing or adding empty files), so we get
805          * the default name from the header.
806          */
807         patch->def_name = git_header_name(line, len);
808         if (patch->def_name && root) {
809                 char *s = xmalloc(root_len + strlen(patch->def_name) + 1);
810                 strcpy(s, root);
811                 strcpy(s + root_len, patch->def_name);
812                 free(patch->def_name);
813                 patch->def_name = s;
814         }
815
816         line += len;
817         size -= len;
818         linenr++;
819         for (offset = len ; size > 0 ; offset += len, size -= len, line += len, linenr++) {
820                 static const struct opentry {
821                         const char *str;
822                         int (*fn)(const char *, struct patch *);
823                 } optable[] = {
824                         { "@@ -", gitdiff_hdrend },
825                         { "--- ", gitdiff_oldname },
826                         { "+++ ", gitdiff_newname },
827                         { "old mode ", gitdiff_oldmode },
828                         { "new mode ", gitdiff_newmode },
829                         { "deleted file mode ", gitdiff_delete },
830                         { "new file mode ", gitdiff_newfile },
831                         { "copy from ", gitdiff_copysrc },
832                         { "copy to ", gitdiff_copydst },
833                         { "rename old ", gitdiff_renamesrc },
834                         { "rename new ", gitdiff_renamedst },
835                         { "rename from ", gitdiff_renamesrc },
836                         { "rename to ", gitdiff_renamedst },
837                         { "similarity index ", gitdiff_similarity },
838                         { "dissimilarity index ", gitdiff_dissimilarity },
839                         { "index ", gitdiff_index },
840                         { "", gitdiff_unrecognized },
841                 };
842                 int i;
843
844                 len = linelen(line, size);
845                 if (!len || line[len-1] != '\n')
846                         break;
847                 for (i = 0; i < ARRAY_SIZE(optable); i++) {
848                         const struct opentry *p = optable + i;
849                         int oplen = strlen(p->str);
850                         if (len < oplen || memcmp(p->str, line, oplen))
851                                 continue;
852                         if (p->fn(line + oplen, patch) < 0)
853                                 return offset;
854                         break;
855                 }
856         }
857
858         return offset;
859 }
860
861 static int parse_num(const char *line, unsigned long *p)
862 {
863         char *ptr;
864
865         if (!isdigit(*line))
866                 return 0;
867         *p = strtoul(line, &ptr, 10);
868         return ptr - line;
869 }
870
871 static int parse_range(const char *line, int len, int offset, const char *expect,
872                        unsigned long *p1, unsigned long *p2)
873 {
874         int digits, ex;
875
876         if (offset < 0 || offset >= len)
877                 return -1;
878         line += offset;
879         len -= offset;
880
881         digits = parse_num(line, p1);
882         if (!digits)
883                 return -1;
884
885         offset += digits;
886         line += digits;
887         len -= digits;
888
889         *p2 = 1;
890         if (*line == ',') {
891                 digits = parse_num(line+1, p2);
892                 if (!digits)
893                         return -1;
894
895                 offset += digits+1;
896                 line += digits+1;
897                 len -= digits+1;
898         }
899
900         ex = strlen(expect);
901         if (ex > len)
902                 return -1;
903         if (memcmp(line, expect, ex))
904                 return -1;
905
906         return offset + ex;
907 }
908
909 static void recount_diff(char *line, int size, struct fragment *fragment)
910 {
911         int oldlines = 0, newlines = 0, ret = 0;
912
913         if (size < 1) {
914                 warning("recount: ignore empty hunk");
915                 return;
916         }
917
918         for (;;) {
919                 int len = linelen(line, size);
920                 size -= len;
921                 line += len;
922
923                 if (size < 1)
924                         break;
925
926                 switch (*line) {
927                 case ' ': case '\n':
928                         newlines++;
929                         /* fall through */
930                 case '-':
931                         oldlines++;
932                         continue;
933                 case '+':
934                         newlines++;
935                         continue;
936                 case '\\':
937                         continue;
938                 case '@':
939                         ret = size < 3 || prefixcmp(line, "@@ ");
940                         break;
941                 case 'd':
942                         ret = size < 5 || prefixcmp(line, "diff ");
943                         break;
944                 default:
945                         ret = -1;
946                         break;
947                 }
948                 if (ret) {
949                         warning("recount: unexpected line: %.*s",
950                                 (int)linelen(line, size), line);
951                         return;
952                 }
953                 break;
954         }
955         fragment->oldlines = oldlines;
956         fragment->newlines = newlines;
957 }
958
959 /*
960  * Parse a unified diff fragment header of the
961  * form "@@ -a,b +c,d @@"
962  */
963 static int parse_fragment_header(char *line, int len, struct fragment *fragment)
964 {
965         int offset;
966
967         if (!len || line[len-1] != '\n')
968                 return -1;
969
970         /* Figure out the number of lines in a fragment */
971         offset = parse_range(line, len, 4, " +", &fragment->oldpos, &fragment->oldlines);
972         offset = parse_range(line, len, offset, " @@", &fragment->newpos, &fragment->newlines);
973
974         return offset;
975 }
976
977 static int find_header(char *line, unsigned long size, int *hdrsize, struct patch *patch)
978 {
979         unsigned long offset, len;
980
981         patch->is_toplevel_relative = 0;
982         patch->is_rename = patch->is_copy = 0;
983         patch->is_new = patch->is_delete = -1;
984         patch->old_mode = patch->new_mode = 0;
985         patch->old_name = patch->new_name = NULL;
986         for (offset = 0; size > 0; offset += len, size -= len, line += len, linenr++) {
987                 unsigned long nextlen;
988
989                 len = linelen(line, size);
990                 if (!len)
991                         break;
992
993                 /* Testing this early allows us to take a few shortcuts.. */
994                 if (len < 6)
995                         continue;
996
997                 /*
998                  * Make sure we don't find any unconnected patch fragments.
999                  * That's a sign that we didn't find a header, and that a
1000                  * patch has become corrupted/broken up.
1001                  */
1002                 if (!memcmp("@@ -", line, 4)) {
1003                         struct fragment dummy;
1004                         if (parse_fragment_header(line, len, &dummy) < 0)
1005                                 continue;
1006                         die("patch fragment without header at line %d: %.*s",
1007                             linenr, (int)len-1, line);
1008                 }
1009
1010                 if (size < len + 6)
1011                         break;
1012
1013                 /*
1014                  * Git patch? It might not have a real patch, just a rename
1015                  * or mode change, so we handle that specially
1016                  */
1017                 if (!memcmp("diff --git ", line, 11)) {
1018                         int git_hdr_len = parse_git_header(line, len, size, patch);
1019                         if (git_hdr_len <= len)
1020                                 continue;
1021                         if (!patch->old_name && !patch->new_name) {
1022                                 if (!patch->def_name)
1023                                         die("git diff header lacks filename information (line %d)", linenr);
1024                                 patch->old_name = patch->new_name = patch->def_name;
1025                         }
1026                         patch->is_toplevel_relative = 1;
1027                         *hdrsize = git_hdr_len;
1028                         return offset;
1029                 }
1030
1031                 /* --- followed by +++ ? */
1032                 if (memcmp("--- ", line,  4) || memcmp("+++ ", line + len, 4))
1033                         continue;
1034
1035                 /*
1036                  * We only accept unified patches, so we want it to
1037                  * at least have "@@ -a,b +c,d @@\n", which is 14 chars
1038                  * minimum ("@@ -0,0 +1 @@\n" is the shortest).
1039                  */
1040                 nextlen = linelen(line + len, size - len);
1041                 if (size < nextlen + 14 || memcmp("@@ -", line + len + nextlen, 4))
1042                         continue;
1043
1044                 /* Ok, we'll consider it a patch */
1045                 parse_traditional_patch(line, line+len, patch);
1046                 *hdrsize = len + nextlen;
1047                 linenr += 2;
1048                 return offset;
1049         }
1050         return -1;
1051 }
1052
1053 static void check_whitespace(const char *line, int len, unsigned ws_rule)
1054 {
1055         char *err;
1056         unsigned result = ws_check(line + 1, len - 1, ws_rule);
1057         if (!result)
1058                 return;
1059
1060         whitespace_error++;
1061         if (squelch_whitespace_errors &&
1062             squelch_whitespace_errors < whitespace_error)
1063                 ;
1064         else {
1065                 err = whitespace_error_string(result);
1066                 fprintf(stderr, "%s:%d: %s.\n%.*s\n",
1067                         patch_input_file, linenr, err, len - 2, line + 1);
1068                 free(err);
1069         }
1070 }
1071
1072 /*
1073  * Parse a unified diff. Note that this really needs to parse each
1074  * fragment separately, since the only way to know the difference
1075  * between a "---" that is part of a patch, and a "---" that starts
1076  * the next patch is to look at the line counts..
1077  */
1078 static int parse_fragment(char *line, unsigned long size,
1079                           struct patch *patch, struct fragment *fragment)
1080 {
1081         int added, deleted;
1082         int len = linelen(line, size), offset;
1083         unsigned long oldlines, newlines;
1084         unsigned long leading, trailing;
1085
1086         offset = parse_fragment_header(line, len, fragment);
1087         if (offset < 0)
1088                 return -1;
1089         if (offset > 0 && patch->recount)
1090                 recount_diff(line + offset, size - offset, fragment);
1091         oldlines = fragment->oldlines;
1092         newlines = fragment->newlines;
1093         leading = 0;
1094         trailing = 0;
1095
1096         /* Parse the thing.. */
1097         line += len;
1098         size -= len;
1099         linenr++;
1100         added = deleted = 0;
1101         for (offset = len;
1102              0 < size;
1103              offset += len, size -= len, line += len, linenr++) {
1104                 if (!oldlines && !newlines)
1105                         break;
1106                 len = linelen(line, size);
1107                 if (!len || line[len-1] != '\n')
1108                         return -1;
1109                 switch (*line) {
1110                 default:
1111                         return -1;
1112                 case '\n': /* newer GNU diff, an empty context line */
1113                 case ' ':
1114                         oldlines--;
1115                         newlines--;
1116                         if (!deleted && !added)
1117                                 leading++;
1118                         trailing++;
1119                         break;
1120                 case '-':
1121                         if (apply_in_reverse &&
1122                             ws_error_action != nowarn_ws_error)
1123                                 check_whitespace(line, len, patch->ws_rule);
1124                         deleted++;
1125                         oldlines--;
1126                         trailing = 0;
1127                         break;
1128                 case '+':
1129                         if (!apply_in_reverse &&
1130                             ws_error_action != nowarn_ws_error)
1131                                 check_whitespace(line, len, patch->ws_rule);
1132                         added++;
1133                         newlines--;
1134                         trailing = 0;
1135                         break;
1136
1137                 /*
1138                  * We allow "\ No newline at end of file". Depending
1139                  * on locale settings when the patch was produced we
1140                  * don't know what this line looks like. The only
1141                  * thing we do know is that it begins with "\ ".
1142                  * Checking for 12 is just for sanity check -- any
1143                  * l10n of "\ No newline..." is at least that long.
1144                  */
1145                 case '\\':
1146                         if (len < 12 || memcmp(line, "\\ ", 2))
1147                                 return -1;
1148                         break;
1149                 }
1150         }
1151         if (oldlines || newlines)
1152                 return -1;
1153         fragment->leading = leading;
1154         fragment->trailing = trailing;
1155
1156         /*
1157          * If a fragment ends with an incomplete line, we failed to include
1158          * it in the above loop because we hit oldlines == newlines == 0
1159          * before seeing it.
1160          */
1161         if (12 < size && !memcmp(line, "\\ ", 2))
1162                 offset += linelen(line, size);
1163
1164         patch->lines_added += added;
1165         patch->lines_deleted += deleted;
1166
1167         if (0 < patch->is_new && oldlines)
1168                 return error("new file depends on old contents");
1169         if (0 < patch->is_delete && newlines)
1170                 return error("deleted file still has contents");
1171         return offset;
1172 }
1173
1174 static int parse_single_patch(char *line, unsigned long size, struct patch *patch)
1175 {
1176         unsigned long offset = 0;
1177         unsigned long oldlines = 0, newlines = 0, context = 0;
1178         struct fragment **fragp = &patch->fragments;
1179
1180         while (size > 4 && !memcmp(line, "@@ -", 4)) {
1181                 struct fragment *fragment;
1182                 int len;
1183
1184                 fragment = xcalloc(1, sizeof(*fragment));
1185                 len = parse_fragment(line, size, patch, fragment);
1186                 if (len <= 0)
1187                         die("corrupt patch at line %d", linenr);
1188                 fragment->patch = line;
1189                 fragment->size = len;
1190                 oldlines += fragment->oldlines;
1191                 newlines += fragment->newlines;
1192                 context += fragment->leading + fragment->trailing;
1193
1194                 *fragp = fragment;
1195                 fragp = &fragment->next;
1196
1197                 offset += len;
1198                 line += len;
1199                 size -= len;
1200         }
1201
1202         /*
1203          * If something was removed (i.e. we have old-lines) it cannot
1204          * be creation, and if something was added it cannot be
1205          * deletion.  However, the reverse is not true; --unified=0
1206          * patches that only add are not necessarily creation even
1207          * though they do not have any old lines, and ones that only
1208          * delete are not necessarily deletion.
1209          *
1210          * Unfortunately, a real creation/deletion patch do _not_ have
1211          * any context line by definition, so we cannot safely tell it
1212          * apart with --unified=0 insanity.  At least if the patch has
1213          * more than one hunk it is not creation or deletion.
1214          */
1215         if (patch->is_new < 0 &&
1216             (oldlines || (patch->fragments && patch->fragments->next)))
1217                 patch->is_new = 0;
1218         if (patch->is_delete < 0 &&
1219             (newlines || (patch->fragments && patch->fragments->next)))
1220                 patch->is_delete = 0;
1221
1222         if (0 < patch->is_new && oldlines)
1223                 die("new file %s depends on old contents", patch->new_name);
1224         if (0 < patch->is_delete && newlines)
1225                 die("deleted file %s still has contents", patch->old_name);
1226         if (!patch->is_delete && !newlines && context)
1227                 fprintf(stderr, "** warning: file %s becomes empty but "
1228                         "is not deleted\n", patch->new_name);
1229
1230         return offset;
1231 }
1232
1233 static inline int metadata_changes(struct patch *patch)
1234 {
1235         return  patch->is_rename > 0 ||
1236                 patch->is_copy > 0 ||
1237                 patch->is_new > 0 ||
1238                 patch->is_delete ||
1239                 (patch->old_mode && patch->new_mode &&
1240                  patch->old_mode != patch->new_mode);
1241 }
1242
1243 static char *inflate_it(const void *data, unsigned long size,
1244                         unsigned long inflated_size)
1245 {
1246         z_stream stream;
1247         void *out;
1248         int st;
1249
1250         memset(&stream, 0, sizeof(stream));
1251
1252         stream.next_in = (unsigned char *)data;
1253         stream.avail_in = size;
1254         stream.next_out = out = xmalloc(inflated_size);
1255         stream.avail_out = inflated_size;
1256         inflateInit(&stream);
1257         st = inflate(&stream, Z_FINISH);
1258         if ((st != Z_STREAM_END) || stream.total_out != inflated_size) {
1259                 free(out);
1260                 return NULL;
1261         }
1262         return out;
1263 }
1264
1265 static struct fragment *parse_binary_hunk(char **buf_p,
1266                                           unsigned long *sz_p,
1267                                           int *status_p,
1268                                           int *used_p)
1269 {
1270         /*
1271          * Expect a line that begins with binary patch method ("literal"
1272          * or "delta"), followed by the length of data before deflating.
1273          * a sequence of 'length-byte' followed by base-85 encoded data
1274          * should follow, terminated by a newline.
1275          *
1276          * Each 5-byte sequence of base-85 encodes up to 4 bytes,
1277          * and we would limit the patch line to 66 characters,
1278          * so one line can fit up to 13 groups that would decode
1279          * to 52 bytes max.  The length byte 'A'-'Z' corresponds
1280          * to 1-26 bytes, and 'a'-'z' corresponds to 27-52 bytes.
1281          */
1282         int llen, used;
1283         unsigned long size = *sz_p;
1284         char *buffer = *buf_p;
1285         int patch_method;
1286         unsigned long origlen;
1287         char *data = NULL;
1288         int hunk_size = 0;
1289         struct fragment *frag;
1290
1291         llen = linelen(buffer, size);
1292         used = llen;
1293
1294         *status_p = 0;
1295
1296         if (!prefixcmp(buffer, "delta ")) {
1297                 patch_method = BINARY_DELTA_DEFLATED;
1298                 origlen = strtoul(buffer + 6, NULL, 10);
1299         }
1300         else if (!prefixcmp(buffer, "literal ")) {
1301                 patch_method = BINARY_LITERAL_DEFLATED;
1302                 origlen = strtoul(buffer + 8, NULL, 10);
1303         }
1304         else
1305                 return NULL;
1306
1307         linenr++;
1308         buffer += llen;
1309         while (1) {
1310                 int byte_length, max_byte_length, newsize;
1311                 llen = linelen(buffer, size);
1312                 used += llen;
1313                 linenr++;
1314                 if (llen == 1) {
1315                         /* consume the blank line */
1316                         buffer++;
1317                         size--;
1318                         break;
1319                 }
1320                 /*
1321                  * Minimum line is "A00000\n" which is 7-byte long,
1322                  * and the line length must be multiple of 5 plus 2.
1323                  */
1324                 if ((llen < 7) || (llen-2) % 5)
1325                         goto corrupt;
1326                 max_byte_length = (llen - 2) / 5 * 4;
1327                 byte_length = *buffer;
1328                 if ('A' <= byte_length && byte_length <= 'Z')
1329                         byte_length = byte_length - 'A' + 1;
1330                 else if ('a' <= byte_length && byte_length <= 'z')
1331                         byte_length = byte_length - 'a' + 27;
1332                 else
1333                         goto corrupt;
1334                 /* if the input length was not multiple of 4, we would
1335                  * have filler at the end but the filler should never
1336                  * exceed 3 bytes
1337                  */
1338                 if (max_byte_length < byte_length ||
1339                     byte_length <= max_byte_length - 4)
1340                         goto corrupt;
1341                 newsize = hunk_size + byte_length;
1342                 data = xrealloc(data, newsize);
1343                 if (decode_85(data + hunk_size, buffer + 1, byte_length))
1344                         goto corrupt;
1345                 hunk_size = newsize;
1346                 buffer += llen;
1347                 size -= llen;
1348         }
1349
1350         frag = xcalloc(1, sizeof(*frag));
1351         frag->patch = inflate_it(data, hunk_size, origlen);
1352         if (!frag->patch)
1353                 goto corrupt;
1354         free(data);
1355         frag->size = origlen;
1356         *buf_p = buffer;
1357         *sz_p = size;
1358         *used_p = used;
1359         frag->binary_patch_method = patch_method;
1360         return frag;
1361
1362  corrupt:
1363         free(data);
1364         *status_p = -1;
1365         error("corrupt binary patch at line %d: %.*s",
1366               linenr-1, llen-1, buffer);
1367         return NULL;
1368 }
1369
1370 static int parse_binary(char *buffer, unsigned long size, struct patch *patch)
1371 {
1372         /*
1373          * We have read "GIT binary patch\n"; what follows is a line
1374          * that says the patch method (currently, either "literal" or
1375          * "delta") and the length of data before deflating; a
1376          * sequence of 'length-byte' followed by base-85 encoded data
1377          * follows.
1378          *
1379          * When a binary patch is reversible, there is another binary
1380          * hunk in the same format, starting with patch method (either
1381          * "literal" or "delta") with the length of data, and a sequence
1382          * of length-byte + base-85 encoded data, terminated with another
1383          * empty line.  This data, when applied to the postimage, produces
1384          * the preimage.
1385          */
1386         struct fragment *forward;
1387         struct fragment *reverse;
1388         int status;
1389         int used, used_1;
1390
1391         forward = parse_binary_hunk(&buffer, &size, &status, &used);
1392         if (!forward && !status)
1393                 /* there has to be one hunk (forward hunk) */
1394                 return error("unrecognized binary patch at line %d", linenr-1);
1395         if (status)
1396                 /* otherwise we already gave an error message */
1397                 return status;
1398
1399         reverse = parse_binary_hunk(&buffer, &size, &status, &used_1);
1400         if (reverse)
1401                 used += used_1;
1402         else if (status) {
1403                 /*
1404                  * Not having reverse hunk is not an error, but having
1405                  * a corrupt reverse hunk is.
1406                  */
1407                 free((void*) forward->patch);
1408                 free(forward);
1409                 return status;
1410         }
1411         forward->next = reverse;
1412         patch->fragments = forward;
1413         patch->is_binary = 1;
1414         return used;
1415 }
1416
1417 static int parse_chunk(char *buffer, unsigned long size, struct patch *patch)
1418 {
1419         int hdrsize, patchsize;
1420         int offset = find_header(buffer, size, &hdrsize, patch);
1421
1422         if (offset < 0)
1423                 return offset;
1424
1425         patch->ws_rule = whitespace_rule(patch->new_name
1426                                          ? patch->new_name
1427                                          : patch->old_name);
1428
1429         patchsize = parse_single_patch(buffer + offset + hdrsize,
1430                                        size - offset - hdrsize, patch);
1431
1432         if (!patchsize) {
1433                 static const char *binhdr[] = {
1434                         "Binary files ",
1435                         "Files ",
1436                         NULL,
1437                 };
1438                 static const char git_binary[] = "GIT binary patch\n";
1439                 int i;
1440                 int hd = hdrsize + offset;
1441                 unsigned long llen = linelen(buffer + hd, size - hd);
1442
1443                 if (llen == sizeof(git_binary) - 1 &&
1444                     !memcmp(git_binary, buffer + hd, llen)) {
1445                         int used;
1446                         linenr++;
1447                         used = parse_binary(buffer + hd + llen,
1448                                             size - hd - llen, patch);
1449                         if (used)
1450                                 patchsize = used + llen;
1451                         else
1452                                 patchsize = 0;
1453                 }
1454                 else if (!memcmp(" differ\n", buffer + hd + llen - 8, 8)) {
1455                         for (i = 0; binhdr[i]; i++) {
1456                                 int len = strlen(binhdr[i]);
1457                                 if (len < size - hd &&
1458                                     !memcmp(binhdr[i], buffer + hd, len)) {
1459                                         linenr++;
1460                                         patch->is_binary = 1;
1461                                         patchsize = llen;
1462                                         break;
1463                                 }
1464                         }
1465                 }
1466
1467                 /* Empty patch cannot be applied if it is a text patch
1468                  * without metadata change.  A binary patch appears
1469                  * empty to us here.
1470                  */
1471                 if ((apply || check) &&
1472                     (!patch->is_binary && !metadata_changes(patch)))
1473                         die("patch with only garbage at line %d", linenr);
1474         }
1475
1476         return offset + hdrsize + patchsize;
1477 }
1478
1479 #define swap(a,b) myswap((a),(b),sizeof(a))
1480
1481 #define myswap(a, b, size) do {         \
1482         unsigned char mytmp[size];      \
1483         memcpy(mytmp, &a, size);                \
1484         memcpy(&a, &b, size);           \
1485         memcpy(&b, mytmp, size);                \
1486 } while (0)
1487
1488 static void reverse_patches(struct patch *p)
1489 {
1490         for (; p; p = p->next) {
1491                 struct fragment *frag = p->fragments;
1492
1493                 swap(p->new_name, p->old_name);
1494                 swap(p->new_mode, p->old_mode);
1495                 swap(p->is_new, p->is_delete);
1496                 swap(p->lines_added, p->lines_deleted);
1497                 swap(p->old_sha1_prefix, p->new_sha1_prefix);
1498
1499                 for (; frag; frag = frag->next) {
1500                         swap(frag->newpos, frag->oldpos);
1501                         swap(frag->newlines, frag->oldlines);
1502                 }
1503         }
1504 }
1505
1506 static const char pluses[] =
1507 "++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++";
1508 static const char minuses[]=
1509 "----------------------------------------------------------------------";
1510
1511 static void show_stats(struct patch *patch)
1512 {
1513         struct strbuf qname = STRBUF_INIT;
1514         char *cp = patch->new_name ? patch->new_name : patch->old_name;
1515         int max, add, del;
1516
1517         quote_c_style(cp, &qname, NULL, 0);
1518
1519         /*
1520          * "scale" the filename
1521          */
1522         max = max_len;
1523         if (max > 50)
1524                 max = 50;
1525
1526         if (qname.len > max) {
1527                 cp = strchr(qname.buf + qname.len + 3 - max, '/');
1528                 if (!cp)
1529                         cp = qname.buf + qname.len + 3 - max;
1530                 strbuf_splice(&qname, 0, cp - qname.buf, "...", 3);
1531         }
1532
1533         if (patch->is_binary) {
1534                 printf(" %-*s |  Bin\n", max, qname.buf);
1535                 strbuf_release(&qname);
1536                 return;
1537         }
1538
1539         printf(" %-*s |", max, qname.buf);
1540         strbuf_release(&qname);
1541
1542         /*
1543          * scale the add/delete
1544          */
1545         max = max + max_change > 70 ? 70 - max : max_change;
1546         add = patch->lines_added;
1547         del = patch->lines_deleted;
1548
1549         if (max_change > 0) {
1550                 int total = ((add + del) * max + max_change / 2) / max_change;
1551                 add = (add * max + max_change / 2) / max_change;
1552                 del = total - add;
1553         }
1554         printf("%5d %.*s%.*s\n", patch->lines_added + patch->lines_deleted,
1555                 add, pluses, del, minuses);
1556 }
1557
1558 static int read_old_data(struct stat *st, const char *path, struct strbuf *buf)
1559 {
1560         switch (st->st_mode & S_IFMT) {
1561         case S_IFLNK:
1562                 strbuf_grow(buf, st->st_size);
1563                 if (readlink(path, buf->buf, st->st_size) != st->st_size)
1564                         return -1;
1565                 strbuf_setlen(buf, st->st_size);
1566                 return 0;
1567         case S_IFREG:
1568                 if (strbuf_read_file(buf, path, st->st_size) != st->st_size)
1569                         return error("unable to open or read %s", path);
1570                 convert_to_git(path, buf->buf, buf->len, buf, 0);
1571                 return 0;
1572         default:
1573                 return -1;
1574         }
1575 }
1576
1577 static void update_pre_post_images(struct image *preimage,
1578                                    struct image *postimage,
1579                                    char *buf,
1580                                    size_t len)
1581 {
1582         int i, ctx;
1583         char *new, *old, *fixed;
1584         struct image fixed_preimage;
1585
1586         /*
1587          * Update the preimage with whitespace fixes.  Note that we
1588          * are not losing preimage->buf -- apply_one_fragment() will
1589          * free "oldlines".
1590          */
1591         prepare_image(&fixed_preimage, buf, len, 1);
1592         assert(fixed_preimage.nr == preimage->nr);
1593         for (i = 0; i < preimage->nr; i++)
1594                 fixed_preimage.line[i].flag = preimage->line[i].flag;
1595         free(preimage->line_allocated);
1596         *preimage = fixed_preimage;
1597
1598         /*
1599          * Adjust the common context lines in postimage, in place.
1600          * This is possible because whitespace fixing does not make
1601          * the string grow.
1602          */
1603         new = old = postimage->buf;
1604         fixed = preimage->buf;
1605         for (i = ctx = 0; i < postimage->nr; i++) {
1606                 size_t len = postimage->line[i].len;
1607                 if (!(postimage->line[i].flag & LINE_COMMON)) {
1608                         /* an added line -- no counterparts in preimage */
1609                         memmove(new, old, len);
1610                         old += len;
1611                         new += len;
1612                         continue;
1613                 }
1614
1615                 /* a common context -- skip it in the original postimage */
1616                 old += len;
1617
1618                 /* and find the corresponding one in the fixed preimage */
1619                 while (ctx < preimage->nr &&
1620                        !(preimage->line[ctx].flag & LINE_COMMON)) {
1621                         fixed += preimage->line[ctx].len;
1622                         ctx++;
1623                 }
1624                 if (preimage->nr <= ctx)
1625                         die("oops");
1626
1627                 /* and copy it in, while fixing the line length */
1628                 len = preimage->line[ctx].len;
1629                 memcpy(new, fixed, len);
1630                 new += len;
1631                 fixed += len;
1632                 postimage->line[i].len = len;
1633                 ctx++;
1634         }
1635
1636         /* Fix the length of the whole thing */
1637         postimage->len = new - postimage->buf;
1638 }
1639
1640 static int match_fragment(struct image *img,
1641                           struct image *preimage,
1642                           struct image *postimage,
1643                           unsigned long try,
1644                           int try_lno,
1645                           unsigned ws_rule,
1646                           int match_beginning, int match_end)
1647 {
1648         int i;
1649         char *fixed_buf, *buf, *orig, *target;
1650
1651         if (preimage->nr + try_lno > img->nr)
1652                 return 0;
1653
1654         if (match_beginning && try_lno)
1655                 return 0;
1656
1657         if (match_end && preimage->nr + try_lno != img->nr)
1658                 return 0;
1659
1660         /* Quick hash check */
1661         for (i = 0; i < preimage->nr; i++)
1662                 if (preimage->line[i].hash != img->line[try_lno + i].hash)
1663                         return 0;
1664
1665         /*
1666          * Do we have an exact match?  If we were told to match
1667          * at the end, size must be exactly at try+fragsize,
1668          * otherwise try+fragsize must be still within the preimage,
1669          * and either case, the old piece should match the preimage
1670          * exactly.
1671          */
1672         if ((match_end
1673              ? (try + preimage->len == img->len)
1674              : (try + preimage->len <= img->len)) &&
1675             !memcmp(img->buf + try, preimage->buf, preimage->len))
1676                 return 1;
1677
1678         if (ws_error_action != correct_ws_error)
1679                 return 0;
1680
1681         /*
1682          * The hunk does not apply byte-by-byte, but the hash says
1683          * it might with whitespace fuzz.
1684          */
1685         fixed_buf = xmalloc(preimage->len + 1);
1686         buf = fixed_buf;
1687         orig = preimage->buf;
1688         target = img->buf + try;
1689         for (i = 0; i < preimage->nr; i++) {
1690                 size_t fixlen; /* length after fixing the preimage */
1691                 size_t oldlen = preimage->line[i].len;
1692                 size_t tgtlen = img->line[try_lno + i].len;
1693                 size_t tgtfixlen; /* length after fixing the target line */
1694                 char tgtfixbuf[1024], *tgtfix;
1695                 int match;
1696
1697                 /* Try fixing the line in the preimage */
1698                 fixlen = ws_fix_copy(buf, orig, oldlen, ws_rule, NULL);
1699
1700                 /* Try fixing the line in the target */
1701                 if (sizeof(tgtfixbuf) > tgtlen)
1702                         tgtfix = tgtfixbuf;
1703                 else
1704                         tgtfix = xmalloc(tgtlen);
1705                 tgtfixlen = ws_fix_copy(tgtfix, target, tgtlen, ws_rule, NULL);
1706
1707                 /*
1708                  * If they match, either the preimage was based on
1709                  * a version before our tree fixed whitespace breakage,
1710                  * or we are lacking a whitespace-fix patch the tree
1711                  * the preimage was based on already had (i.e. target
1712                  * has whitespace breakage, the preimage doesn't).
1713                  * In either case, we are fixing the whitespace breakages
1714                  * so we might as well take the fix together with their
1715                  * real change.
1716                  */
1717                 match = (tgtfixlen == fixlen && !memcmp(tgtfix, buf, fixlen));
1718
1719                 if (tgtfix != tgtfixbuf)
1720                         free(tgtfix);
1721                 if (!match)
1722                         goto unmatch_exit;
1723
1724                 orig += oldlen;
1725                 buf += fixlen;
1726                 target += tgtlen;
1727         }
1728
1729         /*
1730          * Yes, the preimage is based on an older version that still
1731          * has whitespace breakages unfixed, and fixing them makes the
1732          * hunk match.  Update the context lines in the postimage.
1733          */
1734         update_pre_post_images(preimage, postimage,
1735                                fixed_buf, buf - fixed_buf);
1736         return 1;
1737
1738  unmatch_exit:
1739         free(fixed_buf);
1740         return 0;
1741 }
1742
1743 static int find_pos(struct image *img,
1744                     struct image *preimage,
1745                     struct image *postimage,
1746                     int line,
1747                     unsigned ws_rule,
1748                     int match_beginning, int match_end)
1749 {
1750         int i;
1751         unsigned long backwards, forwards, try;
1752         int backwards_lno, forwards_lno, try_lno;
1753
1754         if (preimage->nr > img->nr)
1755                 return -1;
1756
1757         /*
1758          * If match_begining or match_end is specified, there is no
1759          * point starting from a wrong line that will never match and
1760          * wander around and wait for a match at the specified end.
1761          */
1762         if (match_beginning)
1763                 line = 0;
1764         else if (match_end)
1765                 line = img->nr - preimage->nr;
1766
1767         if (line > img->nr)
1768                 line = img->nr;
1769
1770         try = 0;
1771         for (i = 0; i < line; i++)
1772                 try += img->line[i].len;
1773
1774         /*
1775          * There's probably some smart way to do this, but I'll leave
1776          * that to the smart and beautiful people. I'm simple and stupid.
1777          */
1778         backwards = try;
1779         backwards_lno = line;
1780         forwards = try;
1781         forwards_lno = line;
1782         try_lno = line;
1783
1784         for (i = 0; ; i++) {
1785                 if (match_fragment(img, preimage, postimage,
1786                                    try, try_lno, ws_rule,
1787                                    match_beginning, match_end))
1788                         return try_lno;
1789
1790         again:
1791                 if (backwards_lno == 0 && forwards_lno == img->nr)
1792                         break;
1793
1794                 if (i & 1) {
1795                         if (backwards_lno == 0) {
1796                                 i++;
1797                                 goto again;
1798                         }
1799                         backwards_lno--;
1800                         backwards -= img->line[backwards_lno].len;
1801                         try = backwards;
1802                         try_lno = backwards_lno;
1803                 } else {
1804                         if (forwards_lno == img->nr) {
1805                                 i++;
1806                                 goto again;
1807                         }
1808                         forwards += img->line[forwards_lno].len;
1809                         forwards_lno++;
1810                         try = forwards;
1811                         try_lno = forwards_lno;
1812                 }
1813
1814         }
1815         return -1;
1816 }
1817
1818 static void remove_first_line(struct image *img)
1819 {
1820         img->buf += img->line[0].len;
1821         img->len -= img->line[0].len;
1822         img->line++;
1823         img->nr--;
1824 }
1825
1826 static void remove_last_line(struct image *img)
1827 {
1828         img->len -= img->line[--img->nr].len;
1829 }
1830
1831 static void update_image(struct image *img,
1832                          int applied_pos,
1833                          struct image *preimage,
1834                          struct image *postimage)
1835 {
1836         /*
1837          * remove the copy of preimage at offset in img
1838          * and replace it with postimage
1839          */
1840         int i, nr;
1841         size_t remove_count, insert_count, applied_at = 0;
1842         char *result;
1843
1844         for (i = 0; i < applied_pos; i++)
1845                 applied_at += img->line[i].len;
1846
1847         remove_count = 0;
1848         for (i = 0; i < preimage->nr; i++)
1849                 remove_count += img->line[applied_pos + i].len;
1850         insert_count = postimage->len;
1851
1852         /* Adjust the contents */
1853         result = xmalloc(img->len + insert_count - remove_count + 1);
1854         memcpy(result, img->buf, applied_at);
1855         memcpy(result + applied_at, postimage->buf, postimage->len);
1856         memcpy(result + applied_at + postimage->len,
1857                img->buf + (applied_at + remove_count),
1858                img->len - (applied_at + remove_count));
1859         free(img->buf);
1860         img->buf = result;
1861         img->len += insert_count - remove_count;
1862         result[img->len] = '\0';
1863
1864         /* Adjust the line table */
1865         nr = img->nr + postimage->nr - preimage->nr;
1866         if (preimage->nr < postimage->nr) {
1867                 /*
1868                  * NOTE: this knows that we never call remove_first_line()
1869                  * on anything other than pre/post image.
1870                  */
1871                 img->line = xrealloc(img->line, nr * sizeof(*img->line));
1872                 img->line_allocated = img->line;
1873         }
1874         if (preimage->nr != postimage->nr)
1875                 memmove(img->line + applied_pos + postimage->nr,
1876                         img->line + applied_pos + preimage->nr,
1877                         (img->nr - (applied_pos + preimage->nr)) *
1878                         sizeof(*img->line));
1879         memcpy(img->line + applied_pos,
1880                postimage->line,
1881                postimage->nr * sizeof(*img->line));
1882         img->nr = nr;
1883 }
1884
1885 static int apply_one_fragment(struct image *img, struct fragment *frag,
1886                               int inaccurate_eof, unsigned ws_rule)
1887 {
1888         int match_beginning, match_end;
1889         const char *patch = frag->patch;
1890         int size = frag->size;
1891         char *old, *new, *oldlines, *newlines;
1892         int new_blank_lines_at_end = 0;
1893         unsigned long leading, trailing;
1894         int pos, applied_pos;
1895         struct image preimage;
1896         struct image postimage;
1897
1898         memset(&preimage, 0, sizeof(preimage));
1899         memset(&postimage, 0, sizeof(postimage));
1900         oldlines = xmalloc(size);
1901         newlines = xmalloc(size);
1902
1903         old = oldlines;
1904         new = newlines;
1905         while (size > 0) {
1906                 char first;
1907                 int len = linelen(patch, size);
1908                 int plen, added;
1909                 int added_blank_line = 0;
1910
1911                 if (!len)
1912                         break;
1913
1914                 /*
1915                  * "plen" is how much of the line we should use for
1916                  * the actual patch data. Normally we just remove the
1917                  * first character on the line, but if the line is
1918                  * followed by "\ No newline", then we also remove the
1919                  * last one (which is the newline, of course).
1920                  */
1921                 plen = len - 1;
1922                 if (len < size && patch[len] == '\\')
1923                         plen--;
1924                 first = *patch;
1925                 if (apply_in_reverse) {
1926                         if (first == '-')
1927                                 first = '+';
1928                         else if (first == '+')
1929                                 first = '-';
1930                 }
1931
1932                 switch (first) {
1933                 case '\n':
1934                         /* Newer GNU diff, empty context line */
1935                         if (plen < 0)
1936                                 /* ... followed by '\No newline'; nothing */
1937                                 break;
1938                         *old++ = '\n';
1939                         *new++ = '\n';
1940                         add_line_info(&preimage, "\n", 1, LINE_COMMON);
1941                         add_line_info(&postimage, "\n", 1, LINE_COMMON);
1942                         break;
1943                 case ' ':
1944                 case '-':
1945                         memcpy(old, patch + 1, plen);
1946                         add_line_info(&preimage, old, plen,
1947                                       (first == ' ' ? LINE_COMMON : 0));
1948                         old += plen;
1949                         if (first == '-')
1950                                 break;
1951                 /* Fall-through for ' ' */
1952                 case '+':
1953                         /* --no-add does not add new lines */
1954                         if (first == '+' && no_add)
1955                                 break;
1956
1957                         if (first != '+' ||
1958                             !whitespace_error ||
1959                             ws_error_action != correct_ws_error) {
1960                                 memcpy(new, patch + 1, plen);
1961                                 added = plen;
1962                         }
1963                         else {
1964                                 added = ws_fix_copy(new, patch + 1, plen, ws_rule, &applied_after_fixing_ws);
1965                         }
1966                         add_line_info(&postimage, new, added,
1967                                       (first == '+' ? 0 : LINE_COMMON));
1968                         new += added;
1969                         if (first == '+' &&
1970                             added == 1 && new[-1] == '\n')
1971                                 added_blank_line = 1;
1972                         break;
1973                 case '@': case '\\':
1974                         /* Ignore it, we already handled it */
1975                         break;
1976                 default:
1977                         if (apply_verbosely)
1978                                 error("invalid start of line: '%c'", first);
1979                         return -1;
1980                 }
1981                 if (added_blank_line)
1982                         new_blank_lines_at_end++;
1983                 else
1984                         new_blank_lines_at_end = 0;
1985                 patch += len;
1986                 size -= len;
1987         }
1988         if (inaccurate_eof &&
1989             old > oldlines && old[-1] == '\n' &&
1990             new > newlines && new[-1] == '\n') {
1991                 old--;
1992                 new--;
1993         }
1994
1995         leading = frag->leading;
1996         trailing = frag->trailing;
1997
1998         /*
1999          * A hunk to change lines at the beginning would begin with
2000          * @@ -1,L +N,M @@
2001          * but we need to be careful.  -U0 that inserts before the second
2002          * line also has this pattern.
2003          *
2004          * And a hunk to add to an empty file would begin with
2005          * @@ -0,0 +N,M @@
2006          *
2007          * In other words, a hunk that is (frag->oldpos <= 1) with or
2008          * without leading context must match at the beginning.
2009          */
2010         match_beginning = (!frag->oldpos ||
2011                            (frag->oldpos == 1 && !unidiff_zero));
2012
2013         /*
2014          * A hunk without trailing lines must match at the end.
2015          * However, we simply cannot tell if a hunk must match end
2016          * from the lack of trailing lines if the patch was generated
2017          * with unidiff without any context.
2018          */
2019         match_end = !unidiff_zero && !trailing;
2020
2021         pos = frag->newpos ? (frag->newpos - 1) : 0;
2022         preimage.buf = oldlines;
2023         preimage.len = old - oldlines;
2024         postimage.buf = newlines;
2025         postimage.len = new - newlines;
2026         preimage.line = preimage.line_allocated;
2027         postimage.line = postimage.line_allocated;
2028
2029         for (;;) {
2030
2031                 applied_pos = find_pos(img, &preimage, &postimage, pos,
2032                                        ws_rule, match_beginning, match_end);
2033
2034                 if (applied_pos >= 0)
2035                         break;
2036
2037                 /* Am I at my context limits? */
2038                 if ((leading <= p_context) && (trailing <= p_context))
2039                         break;
2040                 if (match_beginning || match_end) {
2041                         match_beginning = match_end = 0;
2042                         continue;
2043                 }
2044
2045                 /*
2046                  * Reduce the number of context lines; reduce both
2047                  * leading and trailing if they are equal otherwise
2048                  * just reduce the larger context.
2049                  */
2050                 if (leading >= trailing) {
2051                         remove_first_line(&preimage);
2052                         remove_first_line(&postimage);
2053                         pos--;
2054                         leading--;
2055                 }
2056                 if (trailing > leading) {
2057                         remove_last_line(&preimage);
2058                         remove_last_line(&postimage);
2059                         trailing--;
2060                 }
2061         }
2062
2063         if (applied_pos >= 0) {
2064                 if (ws_error_action == correct_ws_error &&
2065                     new_blank_lines_at_end &&
2066                     postimage.nr + applied_pos == img->nr) {
2067                         /*
2068                          * If the patch application adds blank lines
2069                          * at the end, and if the patch applies at the
2070                          * end of the image, remove those added blank
2071                          * lines.
2072                          */
2073                         while (new_blank_lines_at_end--)
2074                                 remove_last_line(&postimage);
2075                 }
2076
2077                 /*
2078                  * Warn if it was necessary to reduce the number
2079                  * of context lines.
2080                  */
2081                 if ((leading != frag->leading) ||
2082                     (trailing != frag->trailing))
2083                         fprintf(stderr, "Context reduced to (%ld/%ld)"
2084                                 " to apply fragment at %d\n",
2085                                 leading, trailing, applied_pos+1);
2086                 update_image(img, applied_pos, &preimage, &postimage);
2087         } else {
2088                 if (apply_verbosely)
2089                         error("while searching for:\n%.*s",
2090                               (int)(old - oldlines), oldlines);
2091         }
2092
2093         free(oldlines);
2094         free(newlines);
2095         free(preimage.line_allocated);
2096         free(postimage.line_allocated);
2097
2098         return (applied_pos < 0);
2099 }
2100
2101 static int apply_binary_fragment(struct image *img, struct patch *patch)
2102 {
2103         struct fragment *fragment = patch->fragments;
2104         unsigned long len;
2105         void *dst;
2106
2107         /* Binary patch is irreversible without the optional second hunk */
2108         if (apply_in_reverse) {
2109                 if (!fragment->next)
2110                         return error("cannot reverse-apply a binary patch "
2111                                      "without the reverse hunk to '%s'",
2112                                      patch->new_name
2113                                      ? patch->new_name : patch->old_name);
2114                 fragment = fragment->next;
2115         }
2116         switch (fragment->binary_patch_method) {
2117         case BINARY_DELTA_DEFLATED:
2118                 dst = patch_delta(img->buf, img->len, fragment->patch,
2119                                   fragment->size, &len);
2120                 if (!dst)
2121                         return -1;
2122                 clear_image(img);
2123                 img->buf = dst;
2124                 img->len = len;
2125                 return 0;
2126         case BINARY_LITERAL_DEFLATED:
2127                 clear_image(img);
2128                 img->len = fragment->size;
2129                 img->buf = xmalloc(img->len+1);
2130                 memcpy(img->buf, fragment->patch, img->len);
2131                 img->buf[img->len] = '\0';
2132                 return 0;
2133         }
2134         return -1;
2135 }
2136
2137 static int apply_binary(struct image *img, struct patch *patch)
2138 {
2139         const char *name = patch->old_name ? patch->old_name : patch->new_name;
2140         unsigned char sha1[20];
2141
2142         /*
2143          * For safety, we require patch index line to contain
2144          * full 40-byte textual SHA1 for old and new, at least for now.
2145          */
2146         if (strlen(patch->old_sha1_prefix) != 40 ||
2147             strlen(patch->new_sha1_prefix) != 40 ||
2148             get_sha1_hex(patch->old_sha1_prefix, sha1) ||
2149             get_sha1_hex(patch->new_sha1_prefix, sha1))
2150                 return error("cannot apply binary patch to '%s' "
2151                              "without full index line", name);
2152
2153         if (patch->old_name) {
2154                 /*
2155                  * See if the old one matches what the patch
2156                  * applies to.
2157                  */
2158                 hash_sha1_file(img->buf, img->len, blob_type, sha1);
2159                 if (strcmp(sha1_to_hex(sha1), patch->old_sha1_prefix))
2160                         return error("the patch applies to '%s' (%s), "
2161                                      "which does not match the "
2162                                      "current contents.",
2163                                      name, sha1_to_hex(sha1));
2164         }
2165         else {
2166                 /* Otherwise, the old one must be empty. */
2167                 if (img->len)
2168                         return error("the patch applies to an empty "
2169                                      "'%s' but it is not empty", name);
2170         }
2171
2172         get_sha1_hex(patch->new_sha1_prefix, sha1);
2173         if (is_null_sha1(sha1)) {
2174                 clear_image(img);
2175                 return 0; /* deletion patch */
2176         }
2177
2178         if (has_sha1_file(sha1)) {
2179                 /* We already have the postimage */
2180                 enum object_type type;
2181                 unsigned long size;
2182                 char *result;
2183
2184                 result = read_sha1_file(sha1, &type, &size);
2185                 if (!result)
2186                         return error("the necessary postimage %s for "
2187                                      "'%s' cannot be read",
2188                                      patch->new_sha1_prefix, name);
2189                 clear_image(img);
2190                 img->buf = result;
2191                 img->len = size;
2192         } else {
2193                 /*
2194                  * We have verified buf matches the preimage;
2195                  * apply the patch data to it, which is stored
2196                  * in the patch->fragments->{patch,size}.
2197                  */
2198                 if (apply_binary_fragment(img, patch))
2199                         return error("binary patch does not apply to '%s'",
2200                                      name);
2201
2202                 /* verify that the result matches */
2203                 hash_sha1_file(img->buf, img->len, blob_type, sha1);
2204                 if (strcmp(sha1_to_hex(sha1), patch->new_sha1_prefix))
2205                         return error("binary patch to '%s' creates incorrect result (expecting %s, got %s)",
2206                                 name, patch->new_sha1_prefix, sha1_to_hex(sha1));
2207         }
2208
2209         return 0;
2210 }
2211
2212 static int apply_fragments(struct image *img, struct patch *patch)
2213 {
2214         struct fragment *frag = patch->fragments;
2215         const char *name = patch->old_name ? patch->old_name : patch->new_name;
2216         unsigned ws_rule = patch->ws_rule;
2217         unsigned inaccurate_eof = patch->inaccurate_eof;
2218
2219         if (patch->is_binary)
2220                 return apply_binary(img, patch);
2221
2222         while (frag) {
2223                 if (apply_one_fragment(img, frag, inaccurate_eof, ws_rule)) {
2224                         error("patch failed: %s:%ld", name, frag->oldpos);
2225                         if (!apply_with_reject)
2226                                 return -1;
2227                         frag->rejected = 1;
2228                 }
2229                 frag = frag->next;
2230         }
2231         return 0;
2232 }
2233
2234 static int read_file_or_gitlink(struct cache_entry *ce, struct strbuf *buf)
2235 {
2236         if (!ce)
2237                 return 0;
2238
2239         if (S_ISGITLINK(ce->ce_mode)) {
2240                 strbuf_grow(buf, 100);
2241                 strbuf_addf(buf, "Subproject commit %s\n", sha1_to_hex(ce->sha1));
2242         } else {
2243                 enum object_type type;
2244                 unsigned long sz;
2245                 char *result;
2246
2247                 result = read_sha1_file(ce->sha1, &type, &sz);
2248                 if (!result)
2249                         return -1;
2250                 /* XXX read_sha1_file NUL-terminates */
2251                 strbuf_attach(buf, result, sz, sz + 1);
2252         }
2253         return 0;
2254 }
2255
2256 static struct patch *in_fn_table(const char *name)
2257 {
2258         struct string_list_item *item;
2259
2260         if (name == NULL)
2261                 return NULL;
2262
2263         item = string_list_lookup(name, &fn_table);
2264         if (item != NULL)
2265                 return (struct patch *)item->util;
2266
2267         return NULL;
2268 }
2269
2270 static void add_to_fn_table(struct patch *patch)
2271 {
2272         struct string_list_item *item;
2273
2274         /*
2275          * Always add new_name unless patch is a deletion
2276          * This should cover the cases for normal diffs,
2277          * file creations and copies
2278          */
2279         if (patch->new_name != NULL) {
2280                 item = string_list_insert(patch->new_name, &fn_table);
2281                 item->util = patch;
2282         }
2283
2284         /*
2285          * store a failure on rename/deletion cases because
2286          * later chunks shouldn't patch old names
2287          */
2288         if ((patch->new_name == NULL) || (patch->is_rename)) {
2289                 item = string_list_insert(patch->old_name, &fn_table);
2290                 item->util = (struct patch *) -1;
2291         }
2292 }
2293
2294 static int apply_data(struct patch *patch, struct stat *st, struct cache_entry *ce)
2295 {
2296         struct strbuf buf = STRBUF_INIT;
2297         struct image image;
2298         size_t len;
2299         char *img;
2300         struct patch *tpatch;
2301
2302         if (!(patch->is_copy || patch->is_rename) &&
2303             ((tpatch = in_fn_table(patch->old_name)) != NULL)) {
2304                 if (tpatch == (struct patch *) -1) {
2305                         return error("patch %s has been renamed/deleted",
2306                                 patch->old_name);
2307                 }
2308                 /* We have a patched copy in memory use that */
2309                 strbuf_add(&buf, tpatch->result, tpatch->resultsize);
2310         } else if (cached) {
2311                 if (read_file_or_gitlink(ce, &buf))
2312                         return error("read of %s failed", patch->old_name);
2313         } else if (patch->old_name) {
2314                 if (S_ISGITLINK(patch->old_mode)) {
2315                         if (ce) {
2316                                 read_file_or_gitlink(ce, &buf);
2317                         } else {
2318                                 /*
2319                                  * There is no way to apply subproject
2320                                  * patch without looking at the index.
2321                                  */
2322                                 patch->fragments = NULL;
2323                         }
2324                 } else {
2325                         if (read_old_data(st, patch->old_name, &buf))
2326                                 return error("read of %s failed", patch->old_name);
2327                 }
2328         }
2329
2330         img = strbuf_detach(&buf, &len);
2331         prepare_image(&image, img, len, !patch->is_binary);
2332
2333         if (apply_fragments(&image, patch) < 0)
2334                 return -1; /* note with --reject this succeeds. */
2335         patch->result = image.buf;
2336         patch->resultsize = image.len;
2337         add_to_fn_table(patch);
2338         free(image.line_allocated);
2339
2340         if (0 < patch->is_delete && patch->resultsize)
2341                 return error("removal patch leaves file contents");
2342
2343         return 0;
2344 }
2345
2346 static int check_to_create_blob(const char *new_name, int ok_if_exists)
2347 {
2348         struct stat nst;
2349         if (!lstat(new_name, &nst)) {
2350                 if (S_ISDIR(nst.st_mode) || ok_if_exists)
2351                         return 0;
2352                 /*
2353                  * A leading component of new_name might be a symlink
2354                  * that is going to be removed with this patch, but
2355                  * still pointing at somewhere that has the path.
2356                  * In such a case, path "new_name" does not exist as
2357                  * far as git is concerned.
2358                  */
2359                 if (has_symlink_leading_path(strlen(new_name), new_name))
2360                         return 0;
2361
2362                 return error("%s: already exists in working directory", new_name);
2363         }
2364         else if ((errno != ENOENT) && (errno != ENOTDIR))
2365                 return error("%s: %s", new_name, strerror(errno));
2366         return 0;
2367 }
2368
2369 static int verify_index_match(struct cache_entry *ce, struct stat *st)
2370 {
2371         if (S_ISGITLINK(ce->ce_mode)) {
2372                 if (!S_ISDIR(st->st_mode))
2373                         return -1;
2374                 return 0;
2375         }
2376         return ce_match_stat(ce, st, CE_MATCH_IGNORE_VALID);
2377 }
2378
2379 static int check_preimage(struct patch *patch, struct cache_entry **ce, struct stat *st)
2380 {
2381         const char *old_name = patch->old_name;
2382         struct patch *tpatch = NULL;
2383         int stat_ret = 0;
2384         unsigned st_mode = 0;
2385
2386         /*
2387          * Make sure that we do not have local modifications from the
2388          * index when we are looking at the index.  Also make sure
2389          * we have the preimage file to be patched in the work tree,
2390          * unless --cached, which tells git to apply only in the index.
2391          */
2392         if (!old_name)
2393                 return 0;
2394
2395         assert(patch->is_new <= 0);
2396
2397         if (!(patch->is_copy || patch->is_rename) &&
2398             (tpatch = in_fn_table(old_name)) != NULL) {
2399                 if (tpatch == (struct patch *) -1) {
2400                         return error("%s: has been deleted/renamed", old_name);
2401                 }
2402                 st_mode = tpatch->new_mode;
2403         } else if (!cached) {
2404                 stat_ret = lstat(old_name, st);
2405                 if (stat_ret && errno != ENOENT)
2406                         return error("%s: %s", old_name, strerror(errno));
2407         }
2408
2409         if (check_index && !tpatch) {
2410                 int pos = cache_name_pos(old_name, strlen(old_name));
2411                 if (pos < 0) {
2412                         if (patch->is_new < 0)
2413                                 goto is_new;
2414                         return error("%s: does not exist in index", old_name);
2415                 }
2416                 *ce = active_cache[pos];
2417                 if (stat_ret < 0) {
2418                         struct checkout costate;
2419                         /* checkout */
2420                         costate.base_dir = "";
2421                         costate.base_dir_len = 0;
2422                         costate.force = 0;
2423                         costate.quiet = 0;
2424                         costate.not_new = 0;
2425                         costate.refresh_cache = 1;
2426                         if (checkout_entry(*ce, &costate, NULL) ||
2427                             lstat(old_name, st))
2428                                 return -1;
2429                 }
2430                 if (!cached && verify_index_match(*ce, st))
2431                         return error("%s: does not match index", old_name);
2432                 if (cached)
2433                         st_mode = (*ce)->ce_mode;
2434         } else if (stat_ret < 0) {
2435                 if (patch->is_new < 0)
2436                         goto is_new;
2437                 return error("%s: %s", old_name, strerror(errno));
2438         }
2439
2440         if (!cached)
2441                 st_mode = ce_mode_from_stat(*ce, st->st_mode);
2442
2443         if (patch->is_new < 0)
2444                 patch->is_new = 0;
2445         if (!patch->old_mode)
2446                 patch->old_mode = st_mode;
2447         if ((st_mode ^ patch->old_mode) & S_IFMT)
2448                 return error("%s: wrong type", old_name);
2449         if (st_mode != patch->old_mode)
2450                 fprintf(stderr, "warning: %s has type %o, expected %o\n",
2451                         old_name, st_mode, patch->old_mode);
2452         return 0;
2453
2454  is_new:
2455         patch->is_new = 1;
2456         patch->is_delete = 0;
2457         patch->old_name = NULL;
2458         return 0;
2459 }
2460
2461 static int check_patch(struct patch *patch)
2462 {
2463         struct stat st;
2464         const char *old_name = patch->old_name;
2465         const char *new_name = patch->new_name;
2466         const char *name = old_name ? old_name : new_name;
2467         struct cache_entry *ce = NULL;
2468         int ok_if_exists;
2469         int status;
2470
2471         patch->rejected = 1; /* we will drop this after we succeed */
2472
2473         status = check_preimage(patch, &ce, &st);
2474         if (status)
2475                 return status;
2476         old_name = patch->old_name;
2477
2478         if (in_fn_table(new_name) == (struct patch *) -1)
2479                 /*
2480                  * A type-change diff is always split into a patch to
2481                  * delete old, immediately followed by a patch to
2482                  * create new (see diff.c::run_diff()); in such a case
2483                  * it is Ok that the entry to be deleted by the
2484                  * previous patch is still in the working tree and in
2485                  * the index.
2486                  */
2487                 ok_if_exists = 1;
2488         else
2489                 ok_if_exists = 0;
2490
2491         if (new_name &&
2492             ((0 < patch->is_new) | (0 < patch->is_rename) | patch->is_copy)) {
2493                 if (check_index &&
2494                     cache_name_pos(new_name, strlen(new_name)) >= 0 &&
2495                     !ok_if_exists)
2496                         return error("%s: already exists in index", new_name);
2497                 if (!cached) {
2498                         int err = check_to_create_blob(new_name, ok_if_exists);
2499                         if (err)
2500                                 return err;
2501                 }
2502                 if (!patch->new_mode) {
2503                         if (0 < patch->is_new)
2504                                 patch->new_mode = S_IFREG | 0644;
2505                         else
2506                                 patch->new_mode = patch->old_mode;
2507                 }
2508         }
2509
2510         if (new_name && old_name) {
2511                 int same = !strcmp(old_name, new_name);
2512                 if (!patch->new_mode)
2513                         patch->new_mode = patch->old_mode;
2514                 if ((patch->old_mode ^ patch->new_mode) & S_IFMT)
2515                         return error("new mode (%o) of %s does not match old mode (%o)%s%s",
2516                                 patch->new_mode, new_name, patch->old_mode,
2517                                 same ? "" : " of ", same ? "" : old_name);
2518         }
2519
2520         if (apply_data(patch, &st, ce) < 0)
2521                 return error("%s: patch does not apply", name);
2522         patch->rejected = 0;
2523         return 0;
2524 }
2525
2526 static int check_patch_list(struct patch *patch)
2527 {
2528         int err = 0;
2529
2530         while (patch) {
2531                 if (apply_verbosely)
2532                         say_patch_name(stderr,
2533                                        "Checking patch ", patch, "...\n");
2534                 err |= check_patch(patch);
2535                 patch = patch->next;
2536         }
2537         return err;
2538 }
2539
2540 /* This function tries to read the sha1 from the current index */
2541 static int get_current_sha1(const char *path, unsigned char *sha1)
2542 {
2543         int pos;
2544
2545         if (read_cache() < 0)
2546                 return -1;
2547         pos = cache_name_pos(path, strlen(path));
2548         if (pos < 0)
2549                 return -1;
2550         hashcpy(sha1, active_cache[pos]->sha1);
2551         return 0;
2552 }
2553
2554 /* Build an index that contains the just the files needed for a 3way merge */
2555 static void build_fake_ancestor(struct patch *list, const char *filename)
2556 {
2557         struct patch *patch;
2558         struct index_state result = { 0 };
2559         int fd;
2560
2561         /* Once we start supporting the reverse patch, it may be
2562          * worth showing the new sha1 prefix, but until then...
2563          */
2564         for (patch = list; patch; patch = patch->next) {
2565                 const unsigned char *sha1_ptr;
2566                 unsigned char sha1[20];
2567                 struct cache_entry *ce;
2568                 const char *name;
2569
2570                 name = patch->old_name ? patch->old_name : patch->new_name;
2571                 if (0 < patch->is_new)
2572                         continue;
2573                 else if (get_sha1(patch->old_sha1_prefix, sha1))
2574                         /* git diff has no index line for mode/type changes */
2575                         if (!patch->lines_added && !patch->lines_deleted) {
2576                                 if (get_current_sha1(patch->new_name, sha1) ||
2577                                     get_current_sha1(patch->old_name, sha1))
2578                                         die("mode change for %s, which is not "
2579                                                 "in current HEAD", name);
2580                                 sha1_ptr = sha1;
2581                         } else
2582                                 die("sha1 information is lacking or useless "
2583                                         "(%s).", name);
2584                 else
2585                         sha1_ptr = sha1;
2586
2587                 ce = make_cache_entry(patch->old_mode, sha1_ptr, name, 0, 0);
2588                 if (!ce)
2589                         die("make_cache_entry failed for path '%s'", name);
2590                 if (add_index_entry(&result, ce, ADD_CACHE_OK_TO_ADD))
2591                         die ("Could not add %s to temporary index", name);
2592         }
2593
2594         fd = open(filename, O_WRONLY | O_CREAT, 0666);
2595         if (fd < 0 || write_index(&result, fd) || close(fd))
2596                 die ("Could not write temporary index to %s", filename);
2597
2598         discard_index(&result);
2599 }
2600
2601 static void stat_patch_list(struct patch *patch)
2602 {
2603         int files, adds, dels;
2604
2605         for (files = adds = dels = 0 ; patch ; patch = patch->next) {
2606                 files++;
2607                 adds += patch->lines_added;
2608                 dels += patch->lines_deleted;
2609                 show_stats(patch);
2610         }
2611
2612         printf(" %d files changed, %d insertions(+), %d deletions(-)\n", files, adds, dels);
2613 }
2614
2615 static void numstat_patch_list(struct patch *patch)
2616 {
2617         for ( ; patch; patch = patch->next) {
2618                 const char *name;
2619                 name = patch->new_name ? patch->new_name : patch->old_name;
2620                 if (patch->is_binary)
2621                         printf("-\t-\t");
2622                 else
2623                         printf("%d\t%d\t", patch->lines_added, patch->lines_deleted);
2624                 write_name_quoted(name, stdout, line_termination);
2625         }
2626 }
2627
2628 static void show_file_mode_name(const char *newdelete, unsigned int mode, const char *name)
2629 {
2630         if (mode)
2631                 printf(" %s mode %06o %s\n", newdelete, mode, name);
2632         else
2633                 printf(" %s %s\n", newdelete, name);
2634 }
2635
2636 static void show_mode_change(struct patch *p, int show_name)
2637 {
2638         if (p->old_mode && p->new_mode && p->old_mode != p->new_mode) {
2639                 if (show_name)
2640                         printf(" mode change %06o => %06o %s\n",
2641                                p->old_mode, p->new_mode, p->new_name);
2642                 else
2643                         printf(" mode change %06o => %06o\n",
2644                                p->old_mode, p->new_mode);
2645         }
2646 }
2647
2648 static void show_rename_copy(struct patch *p)
2649 {
2650         const char *renamecopy = p->is_rename ? "rename" : "copy";
2651         const char *old, *new;
2652
2653         /* Find common prefix */
2654         old = p->old_name;
2655         new = p->new_name;
2656         while (1) {
2657                 const char *slash_old, *slash_new;
2658                 slash_old = strchr(old, '/');
2659                 slash_new = strchr(new, '/');
2660                 if (!slash_old ||
2661                     !slash_new ||
2662                     slash_old - old != slash_new - new ||
2663                     memcmp(old, new, slash_new - new))
2664                         break;
2665                 old = slash_old + 1;
2666                 new = slash_new + 1;
2667         }
2668         /* p->old_name thru old is the common prefix, and old and new
2669          * through the end of names are renames
2670          */
2671         if (old != p->old_name)
2672                 printf(" %s %.*s{%s => %s} (%d%%)\n", renamecopy,
2673                        (int)(old - p->old_name), p->old_name,
2674                        old, new, p->score);
2675         else
2676                 printf(" %s %s => %s (%d%%)\n", renamecopy,
2677                        p->old_name, p->new_name, p->score);
2678         show_mode_change(p, 0);
2679 }
2680
2681 static void summary_patch_list(struct patch *patch)
2682 {
2683         struct patch *p;
2684
2685         for (p = patch; p; p = p->next) {
2686                 if (p->is_new)
2687                         show_file_mode_name("create", p->new_mode, p->new_name);
2688                 else if (p->is_delete)
2689                         show_file_mode_name("delete", p->old_mode, p->old_name);
2690                 else {
2691                         if (p->is_rename || p->is_copy)
2692                                 show_rename_copy(p);
2693                         else {
2694                                 if (p->score) {
2695                                         printf(" rewrite %s (%d%%)\n",
2696                                                p->new_name, p->score);
2697                                         show_mode_change(p, 0);
2698                                 }
2699                                 else
2700                                         show_mode_change(p, 1);
2701                         }
2702                 }
2703         }
2704 }
2705
2706 static void patch_stats(struct patch *patch)
2707 {
2708         int lines = patch->lines_added + patch->lines_deleted;
2709
2710         if (lines > max_change)
2711                 max_change = lines;
2712         if (patch->old_name) {
2713                 int len = quote_c_style(patch->old_name, NULL, NULL, 0);
2714                 if (!len)
2715                         len = strlen(patch->old_name);
2716                 if (len > max_len)
2717                         max_len = len;
2718         }
2719         if (patch->new_name) {
2720                 int len = quote_c_style(patch->new_name, NULL, NULL, 0);
2721                 if (!len)
2722                         len = strlen(patch->new_name);
2723                 if (len > max_len)
2724                         max_len = len;
2725         }
2726 }
2727
2728 static void remove_file(struct patch *patch, int rmdir_empty)
2729 {
2730         if (update_index) {
2731                 if (remove_file_from_cache(patch->old_name) < 0)
2732                         die("unable to remove %s from index", patch->old_name);
2733         }
2734         if (!cached) {
2735                 if (S_ISGITLINK(patch->old_mode)) {
2736                         if (rmdir(patch->old_name))
2737                                 warning("unable to remove submodule %s",
2738                                         patch->old_name);
2739                 } else if (!unlink(patch->old_name) && rmdir_empty) {
2740                         remove_path(patch->old_name);
2741                 }
2742         }
2743 }
2744
2745 static void add_index_file(const char *path, unsigned mode, void *buf, unsigned long size)
2746 {
2747         struct stat st;
2748         struct cache_entry *ce;
2749         int namelen = strlen(path);
2750         unsigned ce_size = cache_entry_size(namelen);
2751
2752         if (!update_index)
2753                 return;
2754
2755         ce = xcalloc(1, ce_size);
2756         memcpy(ce->name, path, namelen);
2757         ce->ce_mode = create_ce_mode(mode);
2758         ce->ce_flags = namelen;
2759         if (S_ISGITLINK(mode)) {
2760                 const char *s = buf;
2761
2762                 if (get_sha1_hex(s + strlen("Subproject commit "), ce->sha1))
2763                         die("corrupt patch for subproject %s", path);
2764         } else {
2765                 if (!cached) {
2766                         if (lstat(path, &st) < 0)
2767                                 die("unable to stat newly created file %s",
2768                                     path);
2769                         fill_stat_cache_info(ce, &st);
2770                 }
2771                 if (write_sha1_file(buf, size, blob_type, ce->sha1) < 0)
2772                         die("unable to create backing store for newly created file %s", path);
2773         }
2774         if (add_cache_entry(ce, ADD_CACHE_OK_TO_ADD) < 0)
2775                 die("unable to add cache entry for %s", path);
2776 }
2777
2778 static int try_create_file(const char *path, unsigned int mode, const char *buf, unsigned long size)
2779 {
2780         int fd;
2781         struct strbuf nbuf = STRBUF_INIT;
2782
2783         if (S_ISGITLINK(mode)) {
2784                 struct stat st;
2785                 if (!lstat(path, &st) && S_ISDIR(st.st_mode))
2786                         return 0;
2787                 return mkdir(path, 0777);
2788         }
2789
2790         if (has_symlinks && S_ISLNK(mode))
2791                 /* Although buf:size is counted string, it also is NUL
2792                  * terminated.
2793                  */
2794                 return symlink(buf, path);
2795
2796         fd = open(path, O_CREAT | O_EXCL | O_WRONLY, (mode & 0100) ? 0777 : 0666);
2797         if (fd < 0)
2798                 return -1;
2799
2800         if (convert_to_working_tree(path, buf, size, &nbuf)) {
2801                 size = nbuf.len;
2802                 buf  = nbuf.buf;
2803         }
2804         write_or_die(fd, buf, size);
2805         strbuf_release(&nbuf);
2806
2807         if (close(fd) < 0)
2808                 die("closing file %s: %s", path, strerror(errno));
2809         return 0;
2810 }
2811
2812 /*
2813  * We optimistically assume that the directories exist,
2814  * which is true 99% of the time anyway. If they don't,
2815  * we create them and try again.
2816  */
2817 static void create_one_file(char *path, unsigned mode, const char *buf, unsigned long size)
2818 {
2819         if (cached)
2820                 return;
2821         if (!try_create_file(path, mode, buf, size))
2822                 return;
2823
2824         if (errno == ENOENT) {
2825                 if (safe_create_leading_directories(path))
2826                         return;
2827                 if (!try_create_file(path, mode, buf, size))
2828                         return;
2829         }
2830
2831         if (errno == EEXIST || errno == EACCES) {
2832                 /* We may be trying to create a file where a directory
2833                  * used to be.
2834                  */
2835                 struct stat st;
2836                 if (!lstat(path, &st) && (!S_ISDIR(st.st_mode) || !rmdir(path)))
2837                         errno = EEXIST;
2838         }
2839
2840         if (errno == EEXIST) {
2841                 unsigned int nr = getpid();
2842
2843                 for (;;) {
2844                         const char *newpath;
2845                         newpath = mkpath("%s~%u", path, nr);
2846                         if (!try_create_file(newpath, mode, buf, size)) {
2847                                 if (!rename(newpath, path))
2848                                         return;
2849                                 unlink(newpath);
2850                                 break;
2851                         }
2852                         if (errno != EEXIST)
2853                                 break;
2854                         ++nr;
2855                 }
2856         }
2857         die("unable to write file %s mode %o", path, mode);
2858 }
2859
2860 static void create_file(struct patch *patch)
2861 {
2862         char *path = patch->new_name;
2863         unsigned mode = patch->new_mode;
2864         unsigned long size = patch->resultsize;
2865         char *buf = patch->result;
2866
2867         if (!mode)
2868                 mode = S_IFREG | 0644;
2869         create_one_file(path, mode, buf, size);
2870         add_index_file(path, mode, buf, size);
2871 }
2872
2873 /* phase zero is to remove, phase one is to create */
2874 static void write_out_one_result(struct patch *patch, int phase)
2875 {
2876         if (patch->is_delete > 0) {
2877                 if (phase == 0)
2878                         remove_file(patch, 1);
2879                 return;
2880         }
2881         if (patch->is_new > 0 || patch->is_copy) {
2882                 if (phase == 1)
2883                         create_file(patch);
2884                 return;
2885         }
2886         /*
2887          * Rename or modification boils down to the same
2888          * thing: remove the old, write the new
2889          */
2890         if (phase == 0)
2891                 remove_file(patch, patch->is_rename);
2892         if (phase == 1)
2893                 create_file(patch);
2894 }
2895
2896 static int write_out_one_reject(struct patch *patch)
2897 {
2898         FILE *rej;
2899         char namebuf[PATH_MAX];
2900         struct fragment *frag;
2901         int cnt = 0;
2902
2903         for (cnt = 0, frag = patch->fragments; frag; frag = frag->next) {
2904                 if (!frag->rejected)
2905                         continue;
2906                 cnt++;
2907         }
2908
2909         if (!cnt) {
2910                 if (apply_verbosely)
2911                         say_patch_name(stderr,
2912                                        "Applied patch ", patch, " cleanly.\n");
2913                 return 0;
2914         }
2915
2916         /* This should not happen, because a removal patch that leaves
2917          * contents are marked "rejected" at the patch level.
2918          */
2919         if (!patch->new_name)
2920                 die("internal error");
2921
2922         /* Say this even without --verbose */
2923         say_patch_name(stderr, "Applying patch ", patch, " with");
2924         fprintf(stderr, " %d rejects...\n", cnt);
2925
2926         cnt = strlen(patch->new_name);
2927         if (ARRAY_SIZE(namebuf) <= cnt + 5) {
2928                 cnt = ARRAY_SIZE(namebuf) - 5;
2929                 fprintf(stderr,
2930                         "warning: truncating .rej filename to %.*s.rej",
2931                         cnt - 1, patch->new_name);
2932         }
2933         memcpy(namebuf, patch->new_name, cnt);
2934         memcpy(namebuf + cnt, ".rej", 5);
2935
2936         rej = fopen(namebuf, "w");
2937         if (!rej)
2938                 return error("cannot open %s: %s", namebuf, strerror(errno));
2939
2940         /* Normal git tools never deal with .rej, so do not pretend
2941          * this is a git patch by saying --git nor give extended
2942          * headers.  While at it, maybe please "kompare" that wants
2943          * the trailing TAB and some garbage at the end of line ;-).
2944          */
2945         fprintf(rej, "diff a/%s b/%s\t(rejected hunks)\n",
2946                 patch->new_name, patch->new_name);
2947         for (cnt = 1, frag = patch->fragments;
2948              frag;
2949              cnt++, frag = frag->next) {
2950                 if (!frag->rejected) {
2951                         fprintf(stderr, "Hunk #%d applied cleanly.\n", cnt);
2952                         continue;
2953                 }
2954                 fprintf(stderr, "Rejected hunk #%d.\n", cnt);
2955                 fprintf(rej, "%.*s", frag->size, frag->patch);
2956                 if (frag->patch[frag->size-1] != '\n')
2957                         fputc('\n', rej);
2958         }
2959         fclose(rej);
2960         return -1;
2961 }
2962
2963 static int write_out_results(struct patch *list, int skipped_patch)
2964 {
2965         int phase;
2966         int errs = 0;
2967         struct patch *l;
2968
2969         if (!list && !skipped_patch)
2970                 return error("No changes");
2971
2972         for (phase = 0; phase < 2; phase++) {
2973                 l = list;
2974                 while (l) {
2975                         if (l->rejected)
2976                                 errs = 1;
2977                         else {
2978                                 write_out_one_result(l, phase);
2979                                 if (phase == 1 && write_out_one_reject(l))
2980                                         errs = 1;
2981                         }
2982                         l = l->next;
2983                 }
2984         }
2985         return errs;
2986 }
2987
2988 static struct lock_file lock_file;
2989
2990 static struct string_list limit_by_name;
2991 static int has_include;
2992 static void add_name_limit(const char *name, int exclude)
2993 {
2994         struct string_list_item *it;
2995
2996         it = string_list_append(name, &limit_by_name);
2997         it->util = exclude ? NULL : (void *) 1;
2998 }
2999
3000 static int use_patch(struct patch *p)
3001 {
3002         const char *pathname = p->new_name ? p->new_name : p->old_name;
3003         int i;
3004
3005         /* Paths outside are not touched regardless of "--include" */
3006         if (0 < prefix_length) {
3007                 int pathlen = strlen(pathname);
3008                 if (pathlen <= prefix_length ||
3009                     memcmp(prefix, pathname, prefix_length))
3010                         return 0;
3011         }
3012
3013         /* See if it matches any of exclude/include rule */
3014         for (i = 0; i < limit_by_name.nr; i++) {
3015                 struct string_list_item *it = &limit_by_name.items[i];
3016                 if (!fnmatch(it->string, pathname, 0))
3017                         return (it->util != NULL);
3018         }
3019
3020         /*
3021          * If we had any include, a path that does not match any rule is
3022          * not used.  Otherwise, we saw bunch of exclude rules (or none)
3023          * and such a path is used.
3024          */
3025         return !has_include;
3026 }
3027
3028
3029 static void prefix_one(char **name)
3030 {
3031         char *old_name = *name;
3032         if (!old_name)
3033                 return;
3034         *name = xstrdup(prefix_filename(prefix, prefix_length, *name));
3035         free(old_name);
3036 }
3037
3038 static void prefix_patches(struct patch *p)
3039 {
3040         if (!prefix || p->is_toplevel_relative)
3041                 return;
3042         for ( ; p; p = p->next) {
3043                 if (p->new_name == p->old_name) {
3044                         char *prefixed = p->new_name;
3045                         prefix_one(&prefixed);
3046                         p->new_name = p->old_name = prefixed;
3047                 }
3048                 else {
3049                         prefix_one(&p->new_name);
3050                         prefix_one(&p->old_name);
3051                 }
3052         }
3053 }
3054
3055 #define INACCURATE_EOF  (1<<0)
3056 #define RECOUNT         (1<<1)
3057
3058 static int apply_patch(int fd, const char *filename, int options)
3059 {
3060         size_t offset;
3061         struct strbuf buf = STRBUF_INIT;
3062         struct patch *list = NULL, **listp = &list;
3063         int skipped_patch = 0;
3064
3065         /* FIXME - memory leak when using multiple patch files as inputs */
3066         memset(&fn_table, 0, sizeof(struct string_list));
3067         patch_input_file = filename;
3068         read_patch_file(&buf, fd);
3069         offset = 0;
3070         while (offset < buf.len) {
3071                 struct patch *patch;
3072                 int nr;
3073
3074                 patch = xcalloc(1, sizeof(*patch));
3075                 patch->inaccurate_eof = !!(options & INACCURATE_EOF);
3076                 patch->recount =  !!(options & RECOUNT);
3077                 nr = parse_chunk(buf.buf + offset, buf.len - offset, patch);
3078                 if (nr < 0)
3079                         break;
3080                 if (apply_in_reverse)
3081                         reverse_patches(patch);
3082                 if (prefix)
3083                         prefix_patches(patch);
3084                 if (use_patch(patch)) {
3085                         patch_stats(patch);
3086                         *listp = patch;
3087                         listp = &patch->next;
3088                 }
3089                 else {
3090                         /* perhaps free it a bit better? */
3091                         free(patch);
3092                         skipped_patch++;
3093                 }
3094                 offset += nr;
3095         }
3096
3097         if (whitespace_error && (ws_error_action == die_on_ws_error))
3098                 apply = 0;
3099
3100         update_index = check_index && apply;
3101         if (update_index && newfd < 0)
3102                 newfd = hold_locked_index(&lock_file, 1);
3103
3104         if (check_index) {
3105                 if (read_cache() < 0)
3106                         die("unable to read index file");
3107         }
3108
3109         if ((check || apply) &&
3110             check_patch_list(list) < 0 &&
3111             !apply_with_reject)
3112                 exit(1);
3113
3114         if (apply && write_out_results(list, skipped_patch))
3115                 exit(1);
3116
3117         if (fake_ancestor)
3118                 build_fake_ancestor(list, fake_ancestor);
3119
3120         if (diffstat)
3121                 stat_patch_list(list);
3122
3123         if (numstat)
3124                 numstat_patch_list(list);
3125
3126         if (summary)
3127                 summary_patch_list(list);
3128
3129         strbuf_release(&buf);
3130         return 0;
3131 }
3132
3133 static int git_apply_config(const char *var, const char *value, void *cb)
3134 {
3135         if (!strcmp(var, "apply.whitespace"))
3136                 return git_config_string(&apply_default_whitespace, var, value);
3137         return git_default_config(var, value, cb);
3138 }
3139
3140
3141 int cmd_apply(int argc, const char **argv, const char *unused_prefix)
3142 {
3143         int i;
3144         int read_stdin = 1;
3145         int options = 0;
3146         int errs = 0;
3147         int is_not_gitdir;
3148
3149         const char *whitespace_option = NULL;
3150
3151         prefix = setup_git_directory_gently(&is_not_gitdir);
3152         prefix_length = prefix ? strlen(prefix) : 0;
3153         git_config(git_apply_config, NULL);
3154         if (apply_default_whitespace)
3155                 parse_whitespace_option(apply_default_whitespace);
3156
3157         for (i = 1; i < argc; i++) {
3158                 const char *arg = argv[i];
3159                 char *end;
3160                 int fd;
3161
3162                 if (!strcmp(arg, "-")) {
3163                         errs |= apply_patch(0, "<stdin>", options);
3164                         read_stdin = 0;
3165                         continue;
3166                 }
3167                 if (!prefixcmp(arg, "--exclude=")) {
3168                         add_name_limit(arg + 10, 1);
3169                         continue;
3170                 }
3171                 if (!prefixcmp(arg, "--include=")) {
3172                         add_name_limit(arg + 10, 0);
3173                         has_include = 1;
3174                         continue;
3175                 }
3176                 if (!prefixcmp(arg, "-p")) {
3177                         p_value = atoi(arg + 2);
3178                         p_value_known = 1;
3179                         continue;
3180                 }
3181                 if (!strcmp(arg, "--no-add")) {
3182                         no_add = 1;
3183                         continue;
3184                 }
3185                 if (!strcmp(arg, "--stat")) {
3186                         apply = 0;
3187                         diffstat = 1;
3188                         continue;
3189                 }
3190                 if (!strcmp(arg, "--allow-binary-replacement") ||
3191                     !strcmp(arg, "--binary")) {
3192                         continue; /* now no-op */
3193                 }
3194                 if (!strcmp(arg, "--numstat")) {
3195                         apply = 0;
3196                         numstat = 1;
3197                         continue;
3198                 }
3199                 if (!strcmp(arg, "--summary")) {
3200                         apply = 0;
3201                         summary = 1;
3202                         continue;
3203                 }
3204                 if (!strcmp(arg, "--check")) {
3205                         apply = 0;
3206                         check = 1;
3207                         continue;
3208                 }
3209                 if (!strcmp(arg, "--index")) {
3210                         if (is_not_gitdir)
3211                                 die("--index outside a repository");
3212                         check_index = 1;
3213                         continue;
3214                 }
3215                 if (!strcmp(arg, "--cached")) {
3216                         if (is_not_gitdir)
3217                                 die("--cached outside a repository");
3218                         check_index = 1;
3219                         cached = 1;
3220                         continue;
3221                 }
3222                 if (!strcmp(arg, "--apply")) {
3223                         apply = 1;
3224                         continue;
3225                 }
3226                 if (!strcmp(arg, "--build-fake-ancestor")) {
3227                         apply = 0;
3228                         if (++i >= argc)
3229                                 die ("need a filename");
3230                         fake_ancestor = argv[i];
3231                         continue;
3232                 }
3233                 if (!strcmp(arg, "-z")) {
3234                         line_termination = 0;
3235                         continue;
3236                 }
3237                 if (!prefixcmp(arg, "-C")) {
3238                         p_context = strtoul(arg + 2, &end, 0);
3239                         if (*end != '\0')
3240                                 die("unrecognized context count '%s'", arg + 2);
3241                         continue;
3242                 }
3243                 if (!prefixcmp(arg, "--whitespace=")) {
3244                         whitespace_option = arg + 13;
3245                         parse_whitespace_option(arg + 13);
3246                         continue;
3247                 }
3248                 if (!strcmp(arg, "-R") || !strcmp(arg, "--reverse")) {
3249                         apply_in_reverse = 1;
3250                         continue;
3251                 }
3252                 if (!strcmp(arg, "--unidiff-zero")) {
3253                         unidiff_zero = 1;
3254                         continue;
3255                 }
3256                 if (!strcmp(arg, "--reject")) {
3257                         apply = apply_with_reject = apply_verbosely = 1;
3258                         continue;
3259                 }
3260                 if (!strcmp(arg, "-v") || !strcmp(arg, "--verbose")) {
3261                         apply_verbosely = 1;
3262                         continue;
3263                 }
3264                 if (!strcmp(arg, "--inaccurate-eof")) {
3265                         options |= INACCURATE_EOF;
3266                         continue;
3267                 }
3268                 if (!strcmp(arg, "--recount")) {
3269                         options |= RECOUNT;
3270                         continue;
3271                 }
3272                 if (!prefixcmp(arg, "--directory=")) {
3273                         arg += strlen("--directory=");
3274                         root_len = strlen(arg);
3275                         if (root_len && arg[root_len - 1] != '/') {
3276                                 char *new_root;
3277                                 root = new_root = xmalloc(root_len + 2);
3278                                 strcpy(new_root, arg);
3279                                 strcpy(new_root + root_len++, "/");
3280                         } else
3281                                 root = arg;
3282                         continue;
3283                 }
3284                 if (0 < prefix_length)
3285                         arg = prefix_filename(prefix, prefix_length, arg);
3286
3287                 fd = open(arg, O_RDONLY);
3288                 if (fd < 0)
3289                         die("can't open patch '%s': %s", arg, strerror(errno));
3290                 read_stdin = 0;
3291                 set_default_whitespace_mode(whitespace_option);
3292                 errs |= apply_patch(fd, arg, options);
3293                 close(fd);
3294         }
3295         set_default_whitespace_mode(whitespace_option);
3296         if (read_stdin)
3297                 errs |= apply_patch(0, "<stdin>", options);
3298         if (whitespace_error) {
3299                 if (squelch_whitespace_errors &&
3300                     squelch_whitespace_errors < whitespace_error) {
3301                         int squelched =
3302                                 whitespace_error - squelch_whitespace_errors;
3303                         fprintf(stderr, "warning: squelched %d "
3304                                 "whitespace error%s\n",
3305                                 squelched,
3306                                 squelched == 1 ? "" : "s");
3307                 }
3308                 if (ws_error_action == die_on_ws_error)
3309                         die("%d line%s add%s whitespace errors.",
3310                             whitespace_error,
3311                             whitespace_error == 1 ? "" : "s",
3312                             whitespace_error == 1 ? "s" : "");
3313                 if (applied_after_fixing_ws && apply)
3314                         fprintf(stderr, "warning: %d line%s applied after"
3315                                 " fixing whitespace errors.\n",
3316                                 applied_after_fixing_ws,
3317                                 applied_after_fixing_ws == 1 ? "" : "s");
3318                 else if (whitespace_error)
3319                         fprintf(stderr, "warning: %d line%s add%s whitespace errors.\n",
3320                                 whitespace_error,
3321                                 whitespace_error == 1 ? "" : "s",
3322                                 whitespace_error == 1 ? "s" : "");
3323         }
3324
3325         if (update_index) {
3326                 if (write_cache(newfd, active_cache, active_nr) ||
3327                     commit_locked_index(&lock_file))
3328                         die("Unable to write new index file");
3329         }
3330
3331         return !!errs;
3332 }