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