Merge branch 'maint'
[git] / builtin-apply.c
1 /*
2  * apply.c
3  *
4  * Copyright (C) Linus Torvalds, 2005
5  *
6  * This applies patches on top of some (arbitrary) version of the SCM.
7  *
8  */
9 #include "cache.h"
10 #include "cache-tree.h"
11 #include "quote.h"
12 #include "blob.h"
13 #include "delta.h"
14 #include "builtin.h"
15 #include "string-list.h"
16 #include "dir.h"
17
18 /*
19  *  --check turns on checking that the working tree matches the
20  *    files that are being modified, but doesn't apply the patch
21  *  --stat does just a diffstat, and doesn't actually apply
22  *  --numstat does numeric diffstat, and doesn't actually apply
23  *  --index-info shows the old and new index info for paths if available.
24  *  --index updates the cache as well.
25  *  --cached updates only the cache without ever touching the working tree.
26  */
27 static const char *prefix;
28 static int prefix_length = -1;
29 static int newfd = -1;
30
31 static int unidiff_zero;
32 static int p_value = 1;
33 static int p_value_known;
34 static int check_index;
35 static int update_index;
36 static int cached;
37 static int diffstat;
38 static int numstat;
39 static int summary;
40 static int check;
41 static int apply = 1;
42 static int apply_in_reverse;
43 static int apply_with_reject;
44 static int apply_verbosely;
45 static int no_add;
46 static const char *fake_ancestor;
47 static int line_termination = '\n';
48 static unsigned long p_context = ULONG_MAX;
49 static const char apply_usage[] =
50 "git apply [--stat] [--numstat] [--summary] [--check] [--index] [--cached] [--apply] [--no-add] [--index-info] [--allow-binary-replacement] [--reverse] [--reject] [--verbose] [-z] [-pNUM] [-CNUM] [--whitespace=<nowarn|warn|fix|error|error-all>] <patch>...";
51
52 static enum ws_error_action {
53         nowarn_ws_error,
54         warn_on_ws_error,
55         die_on_ws_error,
56         correct_ws_error,
57 } ws_error_action = warn_on_ws_error;
58 static int whitespace_error;
59 static int squelch_whitespace_errors = 5;
60 static int applied_after_fixing_ws;
61 static const char *patch_input_file;
62 static const char *root;
63 static int root_len;
64
65 static void parse_whitespace_option(const char *option)
66 {
67         if (!option) {
68                 ws_error_action = warn_on_ws_error;
69                 return;
70         }
71         if (!strcmp(option, "warn")) {
72                 ws_error_action = warn_on_ws_error;
73                 return;
74         }
75         if (!strcmp(option, "nowarn")) {
76                 ws_error_action = nowarn_ws_error;
77                 return;
78         }
79         if (!strcmp(option, "error")) {
80                 ws_error_action = die_on_ws_error;
81                 return;
82         }
83         if (!strcmp(option, "error-all")) {
84                 ws_error_action = die_on_ws_error;
85                 squelch_whitespace_errors = 0;
86                 return;
87         }
88         if (!strcmp(option, "strip") || !strcmp(option, "fix")) {
89                 ws_error_action = correct_ws_error;
90                 return;
91         }
92         die("unrecognized whitespace option '%s'", option);
93 }
94
95 static void set_default_whitespace_mode(const char *whitespace_option)
96 {
97         if (!whitespace_option && !apply_default_whitespace)
98                 ws_error_action = (apply ? warn_on_ws_error : nowarn_ws_error);
99 }
100
101 /*
102  * For "diff-stat" like behaviour, we keep track of the biggest change
103  * we've seen, and the longest filename. That allows us to do simple
104  * scaling.
105  */
106 static int max_change, max_len;
107
108 /*
109  * Various "current state", notably line numbers and what
110  * file (and how) we're patching right now.. The "is_xxxx"
111  * things are flags, where -1 means "don't know yet".
112  */
113 static int linenr = 1;
114
115 /*
116  * This represents one "hunk" from a patch, starting with
117  * "@@ -oldpos,oldlines +newpos,newlines @@" marker.  The
118  * patch text is pointed at by patch, and its byte length
119  * is stored in size.  leading and trailing are the number
120  * of context lines.
121  */
122 struct fragment {
123         unsigned long leading, trailing;
124         unsigned long oldpos, oldlines;
125         unsigned long newpos, newlines;
126         const char *patch;
127         int size;
128         int rejected;
129         struct fragment *next;
130 };
131
132 /*
133  * When dealing with a binary patch, we reuse "leading" field
134  * to store the type of the binary hunk, either deflated "delta"
135  * or deflated "literal".
136  */
137 #define binary_patch_method leading
138 #define BINARY_DELTA_DEFLATED   1
139 #define BINARY_LITERAL_DEFLATED 2
140
141 /*
142  * This represents a "patch" to a file, both metainfo changes
143  * such as creation/deletion, filemode and content changes represented
144  * as a series of fragments.
145  */
146 struct patch {
147         char *new_name, *old_name, *def_name;
148         unsigned int old_mode, new_mode;
149         int is_new, is_delete;  /* -1 = unknown, 0 = false, 1 = true */
150         int rejected;
151         unsigned ws_rule;
152         unsigned long deflate_origlen;
153         int lines_added, lines_deleted;
154         int score;
155         unsigned int is_toplevel_relative:1;
156         unsigned int inaccurate_eof:1;
157         unsigned int is_binary:1;
158         unsigned int is_copy:1;
159         unsigned int is_rename:1;
160         unsigned int recount:1;
161         struct fragment *fragments;
162         char *result;
163         size_t resultsize;
164         char old_sha1_prefix[41];
165         char new_sha1_prefix[41];
166         struct patch *next;
167 };
168
169 /*
170  * A line in a file, len-bytes long (includes the terminating LF,
171  * except for an incomplete line at the end if the file ends with
172  * one), and its contents hashes to 'hash'.
173  */
174 struct line {
175         size_t len;
176         unsigned hash : 24;
177         unsigned flag : 8;
178 #define LINE_COMMON     1
179 };
180
181 /*
182  * This represents a "file", which is an array of "lines".
183  */
184 struct image {
185         char *buf;
186         size_t len;
187         size_t nr;
188         size_t alloc;
189         struct line *line_allocated;
190         struct line *line;
191 };
192
193 /*
194  * Records filenames that have been touched, in order to handle
195  * the case where more than one patches touch the same file.
196  */
197
198 static struct string_list fn_table;
199
200 static uint32_t hash_line(const char *cp, size_t len)
201 {
202         size_t i;
203         uint32_t h;
204         for (i = 0, h = 0; i < len; i++) {
205                 if (!isspace(cp[i])) {
206                         h = h * 3 + (cp[i] & 0xff);
207                 }
208         }
209         return h;
210 }
211
212 static void add_line_info(struct image *img, const char *bol, size_t len, unsigned flag)
213 {
214         ALLOC_GROW(img->line_allocated, img->nr + 1, img->alloc);
215         img->line_allocated[img->nr].len = len;
216         img->line_allocated[img->nr].hash = hash_line(bol, len);
217         img->line_allocated[img->nr].flag = flag;
218         img->nr++;
219 }
220
221 static void prepare_image(struct image *image, char *buf, size_t len,
222                           int prepare_linetable)
223 {
224         const char *cp, *ep;
225
226         memset(image, 0, sizeof(*image));
227         image->buf = buf;
228         image->len = len;
229
230         if (!prepare_linetable)
231                 return;
232
233         ep = image->buf + image->len;
234         cp = image->buf;
235         while (cp < ep) {
236                 const char *next;
237                 for (next = cp; next < ep && *next != '\n'; next++)
238                         ;
239                 if (next < ep)
240                         next++;
241                 add_line_info(image, cp, next - cp, 0);
242                 cp = next;
243         }
244         image->line = image->line_allocated;
245 }
246
247 static void clear_image(struct image *image)
248 {
249         free(image->buf);
250         image->buf = NULL;
251         image->len = 0;
252 }
253
254 static void say_patch_name(FILE *output, const char *pre,
255                            struct patch *patch, const char *post)
256 {
257         fputs(pre, output);
258         if (patch->old_name && patch->new_name &&
259             strcmp(patch->old_name, patch->new_name)) {
260                 quote_c_style(patch->old_name, NULL, output, 0);
261                 fputs(" => ", output);
262                 quote_c_style(patch->new_name, NULL, output, 0);
263         } else {
264                 const char *n = patch->new_name;
265                 if (!n)
266                         n = patch->old_name;
267                 quote_c_style(n, NULL, output, 0);
268         }
269         fputs(post, output);
270 }
271
272 #define CHUNKSIZE (8192)
273 #define SLOP (16)
274
275 static void read_patch_file(struct strbuf *sb, int fd)
276 {
277         if (strbuf_read(sb, fd, 0) < 0)
278                 die("git apply: read returned %s", strerror(errno));
279
280         /*
281          * Make sure that we have some slop in the buffer
282          * so that we can do speculative "memcmp" etc, and
283          * see to it that it is NUL-filled.
284          */
285         strbuf_grow(sb, SLOP);
286         memset(sb->buf + sb->len, 0, SLOP);
287 }
288
289 static unsigned long linelen(const char *buffer, unsigned long size)
290 {
291         unsigned long len = 0;
292         while (size--) {
293                 len++;
294                 if (*buffer++ == '\n')
295                         break;
296         }
297         return len;
298 }
299
300 static int is_dev_null(const char *str)
301 {
302         return !memcmp("/dev/null", str, 9) && isspace(str[9]);
303 }
304
305 #define TERM_SPACE      1
306 #define TERM_TAB        2
307
308 static int name_terminate(const char *name, int namelen, int c, int terminate)
309 {
310         if (c == ' ' && !(terminate & TERM_SPACE))
311                 return 0;
312         if (c == '\t' && !(terminate & TERM_TAB))
313                 return 0;
314
315         return 1;
316 }
317
318 static char *find_name(const char *line, char *def, int p_value, int terminate)
319 {
320         int len;
321         const char *start = line;
322
323         if (*line == '"') {
324                 struct strbuf name;
325
326                 /*
327                  * Proposed "new-style" GNU patch/diff format; see
328                  * http://marc.theaimsgroup.com/?l=git&m=112927316408690&w=2
329                  */
330                 strbuf_init(&name, 0);
331                 if (!unquote_c_style(&name, line, NULL)) {
332                         char *cp;
333
334                         for (cp = name.buf; p_value; p_value--) {
335                                 cp = strchr(cp, '/');
336                                 if (!cp)
337                                         break;
338                                 cp++;
339                         }
340                         if (cp) {
341                                 /* name can later be freed, so we need
342                                  * to memmove, not just return cp
343                                  */
344                                 strbuf_remove(&name, 0, cp - name.buf);
345                                 free(def);
346                                 if (root)
347                                         strbuf_insert(&name, 0, root, root_len);
348                                 return strbuf_detach(&name, NULL);
349                         }
350                 }
351                 strbuf_release(&name);
352         }
353
354         for (;;) {
355                 char c = *line;
356
357                 if (isspace(c)) {
358                         if (c == '\n')
359                                 break;
360                         if (name_terminate(start, line-start, c, terminate))
361                                 break;
362                 }
363                 line++;
364                 if (c == '/' && !--p_value)
365                         start = line;
366         }
367         if (!start)
368                 return def;
369         len = line - start;
370         if (!len)
371                 return def;
372
373         /*
374          * Generally we prefer the shorter name, especially
375          * if the other one is just a variation of that with
376          * something else tacked on to the end (ie "file.orig"
377          * or "file~").
378          */
379         if (def) {
380                 int deflen = strlen(def);
381                 if (deflen < len && !strncmp(start, def, deflen))
382                         return def;
383                 free(def);
384         }
385
386         if (root) {
387                 char *ret = xmalloc(root_len + len + 1);
388                 strcpy(ret, root);
389                 memcpy(ret + root_len, start, len);
390                 ret[root_len + len] = '\0';
391                 return ret;
392         }
393
394         return xmemdupz(start, len);
395 }
396
397 static int count_slashes(const char *cp)
398 {
399         int cnt = 0;
400         char ch;
401
402         while ((ch = *cp++))
403                 if (ch == '/')
404                         cnt++;
405         return cnt;
406 }
407
408 /*
409  * Given the string after "--- " or "+++ ", guess the appropriate
410  * p_value for the given patch.
411  */
412 static int guess_p_value(const char *nameline)
413 {
414         char *name, *cp;
415         int val = -1;
416
417         if (is_dev_null(nameline))
418                 return -1;
419         name = find_name(nameline, NULL, 0, TERM_SPACE | TERM_TAB);
420         if (!name)
421                 return -1;
422         cp = strchr(name, '/');
423         if (!cp)
424                 val = 0;
425         else if (prefix) {
426                 /*
427                  * Does it begin with "a/$our-prefix" and such?  Then this is
428                  * very likely to apply to our directory.
429                  */
430                 if (!strncmp(name, prefix, prefix_length))
431                         val = count_slashes(prefix);
432                 else {
433                         cp++;
434                         if (!strncmp(cp, prefix, prefix_length))
435                                 val = count_slashes(prefix) + 1;
436                 }
437         }
438         free(name);
439         return val;
440 }
441
442 /*
443  * Get the name etc info from the ---/+++ lines of a traditional patch header
444  *
445  * FIXME! The end-of-filename heuristics are kind of screwy. For existing
446  * files, we can happily check the index for a match, but for creating a
447  * new file we should try to match whatever "patch" does. I have no idea.
448  */
449 static void parse_traditional_patch(const char *first, const char *second, struct patch *patch)
450 {
451         char *name;
452
453         first += 4;     /* skip "--- " */
454         second += 4;    /* skip "+++ " */
455         if (!p_value_known) {
456                 int p, q;
457                 p = guess_p_value(first);
458                 q = guess_p_value(second);
459                 if (p < 0) p = q;
460                 if (0 <= p && p == q) {
461                         p_value = p;
462                         p_value_known = 1;
463                 }
464         }
465         if (is_dev_null(first)) {
466                 patch->is_new = 1;
467                 patch->is_delete = 0;
468                 name = find_name(second, NULL, p_value, TERM_SPACE | TERM_TAB);
469                 patch->new_name = name;
470         } else if (is_dev_null(second)) {
471                 patch->is_new = 0;
472                 patch->is_delete = 1;
473                 name = find_name(first, NULL, p_value, TERM_SPACE | TERM_TAB);
474                 patch->old_name = name;
475         } else {
476                 name = find_name(first, NULL, p_value, TERM_SPACE | TERM_TAB);
477                 name = find_name(second, name, p_value, TERM_SPACE | TERM_TAB);
478                 patch->old_name = patch->new_name = name;
479         }
480         if (!name)
481                 die("unable to find filename in patch at line %d", linenr);
482 }
483
484 static int gitdiff_hdrend(const char *line, struct patch *patch)
485 {
486         return -1;
487 }
488
489 /*
490  * We're anal about diff header consistency, to make
491  * sure that we don't end up having strange ambiguous
492  * patches floating around.
493  *
494  * As a result, gitdiff_{old|new}name() will check
495  * their names against any previous information, just
496  * to make sure..
497  */
498 static char *gitdiff_verify_name(const char *line, int isnull, char *orig_name, const char *oldnew)
499 {
500         if (!orig_name && !isnull)
501                 return find_name(line, NULL, p_value, TERM_TAB);
502
503         if (orig_name) {
504                 int len;
505                 const char *name;
506                 char *another;
507                 name = orig_name;
508                 len = strlen(name);
509                 if (isnull)
510                         die("git apply: bad git-diff - expected /dev/null, got %s on line %d", name, linenr);
511                 another = find_name(line, NULL, p_value, TERM_TAB);
512                 if (!another || memcmp(another, name, len))
513                         die("git apply: bad git-diff - inconsistent %s filename on line %d", oldnew, linenr);
514                 free(another);
515                 return orig_name;
516         }
517         else {
518                 /* expect "/dev/null" */
519                 if (memcmp("/dev/null", line, 9) || line[9] != '\n')
520                         die("git apply: bad git-diff - expected /dev/null on line %d", linenr);
521                 return NULL;
522         }
523 }
524
525 static int gitdiff_oldname(const char *line, struct patch *patch)
526 {
527         patch->old_name = gitdiff_verify_name(line, patch->is_new, patch->old_name, "old");
528         return 0;
529 }
530
531 static int gitdiff_newname(const char *line, struct patch *patch)
532 {
533         patch->new_name = gitdiff_verify_name(line, patch->is_delete, patch->new_name, "new");
534         return 0;
535 }
536
537 static int gitdiff_oldmode(const char *line, struct patch *patch)
538 {
539         patch->old_mode = strtoul(line, NULL, 8);
540         return 0;
541 }
542
543 static int gitdiff_newmode(const char *line, struct patch *patch)
544 {
545         patch->new_mode = strtoul(line, NULL, 8);
546         return 0;
547 }
548
549 static int gitdiff_delete(const char *line, struct patch *patch)
550 {
551         patch->is_delete = 1;
552         patch->old_name = patch->def_name;
553         return gitdiff_oldmode(line, patch);
554 }
555
556 static int gitdiff_newfile(const char *line, struct patch *patch)
557 {
558         patch->is_new = 1;
559         patch->new_name = patch->def_name;
560         return gitdiff_newmode(line, patch);
561 }
562
563 static int gitdiff_copysrc(const char *line, struct patch *patch)
564 {
565         patch->is_copy = 1;
566         patch->old_name = find_name(line, NULL, 0, 0);
567         return 0;
568 }
569
570 static int gitdiff_copydst(const char *line, struct patch *patch)
571 {
572         patch->is_copy = 1;
573         patch->new_name = find_name(line, NULL, 0, 0);
574         return 0;
575 }
576
577 static int gitdiff_renamesrc(const char *line, struct patch *patch)
578 {
579         patch->is_rename = 1;
580         patch->old_name = find_name(line, NULL, 0, 0);
581         return 0;
582 }
583
584 static int gitdiff_renamedst(const char *line, struct patch *patch)
585 {
586         patch->is_rename = 1;
587         patch->new_name = find_name(line, NULL, 0, 0);
588         return 0;
589 }
590
591 static int gitdiff_similarity(const char *line, struct patch *patch)
592 {
593         if ((patch->score = strtoul(line, NULL, 10)) == ULONG_MAX)
594                 patch->score = 0;
595         return 0;
596 }
597
598 static int gitdiff_dissimilarity(const char *line, struct patch *patch)
599 {
600         if ((patch->score = strtoul(line, NULL, 10)) == ULONG_MAX)
601                 patch->score = 0;
602         return 0;
603 }
604
605 static int gitdiff_index(const char *line, struct patch *patch)
606 {
607         /*
608          * index line is N hexadecimal, "..", N hexadecimal,
609          * and optional space with octal mode.
610          */
611         const char *ptr, *eol;
612         int len;
613
614         ptr = strchr(line, '.');
615         if (!ptr || ptr[1] != '.' || 40 < ptr - line)
616                 return 0;
617         len = ptr - line;
618         memcpy(patch->old_sha1_prefix, line, len);
619         patch->old_sha1_prefix[len] = 0;
620
621         line = ptr + 2;
622         ptr = strchr(line, ' ');
623         eol = strchr(line, '\n');
624
625         if (!ptr || eol < ptr)
626                 ptr = eol;
627         len = ptr - line;
628
629         if (40 < len)
630                 return 0;
631         memcpy(patch->new_sha1_prefix, line, len);
632         patch->new_sha1_prefix[len] = 0;
633         if (*ptr == ' ')
634                 patch->new_mode = patch->old_mode = strtoul(ptr+1, NULL, 8);
635         return 0;
636 }
637
638 /*
639  * This is normal for a diff that doesn't change anything: we'll fall through
640  * into the next diff. Tell the parser to break out.
641  */
642 static int gitdiff_unrecognized(const char *line, struct patch *patch)
643 {
644         return -1;
645 }
646
647 static const char *stop_at_slash(const char *line, int llen)
648 {
649         int i;
650
651         for (i = 0; i < llen; i++) {
652                 int ch = line[i];
653                 if (ch == '/')
654                         return line + i;
655         }
656         return NULL;
657 }
658
659 /*
660  * This is to extract the same name that appears on "diff --git"
661  * line.  We do not find and return anything if it is a rename
662  * patch, and it is OK because we will find the name elsewhere.
663  * We need to reliably find name only when it is mode-change only,
664  * creation or deletion of an empty file.  In any of these cases,
665  * both sides are the same name under a/ and b/ respectively.
666  */
667 static char *git_header_name(char *line, int llen)
668 {
669         const char *name;
670         const char *second = NULL;
671         size_t len;
672
673         line += strlen("diff --git ");
674         llen -= strlen("diff --git ");
675
676         if (*line == '"') {
677                 const char *cp;
678                 struct strbuf first;
679                 struct strbuf sp;
680
681                 strbuf_init(&first, 0);
682                 strbuf_init(&sp, 0);
683
684                 if (unquote_c_style(&first, line, &second))
685                         goto free_and_fail1;
686
687                 /* advance to the first slash */
688                 cp = stop_at_slash(first.buf, first.len);
689                 /* we do not accept absolute paths */
690                 if (!cp || cp == first.buf)
691                         goto free_and_fail1;
692                 strbuf_remove(&first, 0, cp + 1 - first.buf);
693
694                 /*
695                  * second points at one past closing dq of name.
696                  * find the second name.
697                  */
698                 while ((second < line + llen) && isspace(*second))
699                         second++;
700
701                 if (line + llen <= second)
702                         goto free_and_fail1;
703                 if (*second == '"') {
704                         if (unquote_c_style(&sp, second, NULL))
705                                 goto free_and_fail1;
706                         cp = stop_at_slash(sp.buf, sp.len);
707                         if (!cp || cp == sp.buf)
708                                 goto free_and_fail1;
709                         /* They must match, otherwise ignore */
710                         if (strcmp(cp + 1, first.buf))
711                                 goto free_and_fail1;
712                         strbuf_release(&sp);
713                         return strbuf_detach(&first, NULL);
714                 }
715
716                 /* unquoted second */
717                 cp = stop_at_slash(second, line + llen - second);
718                 if (!cp || cp == second)
719                         goto free_and_fail1;
720                 cp++;
721                 if (line + llen - cp != first.len + 1 ||
722                     memcmp(first.buf, cp, first.len))
723                         goto free_and_fail1;
724                 return strbuf_detach(&first, NULL);
725
726         free_and_fail1:
727                 strbuf_release(&first);
728                 strbuf_release(&sp);
729                 return NULL;
730         }
731
732         /* unquoted first name */
733         name = stop_at_slash(line, llen);
734         if (!name || name == line)
735                 return NULL;
736         name++;
737
738         /*
739          * since the first name is unquoted, a dq if exists must be
740          * the beginning of the second name.
741          */
742         for (second = name; second < line + llen; second++) {
743                 if (*second == '"') {
744                         struct strbuf sp;
745                         const char *np;
746
747                         strbuf_init(&sp, 0);
748                         if (unquote_c_style(&sp, second, NULL))
749                                 goto free_and_fail2;
750
751                         np = stop_at_slash(sp.buf, sp.len);
752                         if (!np || np == sp.buf)
753                                 goto free_and_fail2;
754                         np++;
755
756                         len = sp.buf + sp.len - np;
757                         if (len < second - name &&
758                             !strncmp(np, name, len) &&
759                             isspace(name[len])) {
760                                 /* Good */
761                                 strbuf_remove(&sp, 0, np - sp.buf);
762                                 return strbuf_detach(&sp, NULL);
763                         }
764
765                 free_and_fail2:
766                         strbuf_release(&sp);
767                         return NULL;
768                 }
769         }
770
771         /*
772          * Accept a name only if it shows up twice, exactly the same
773          * form.
774          */
775         for (len = 0 ; ; len++) {
776                 switch (name[len]) {
777                 default:
778                         continue;
779                 case '\n':
780                         return NULL;
781                 case '\t': case ' ':
782                         second = name+len;
783                         for (;;) {
784                                 char c = *second++;
785                                 if (c == '\n')
786                                         return NULL;
787                                 if (c == '/')
788                                         break;
789                         }
790                         if (second[len] == '\n' && !memcmp(name, second, len)) {
791                                 return xmemdupz(name, len);
792                         }
793                 }
794         }
795 }
796
797 /* Verify that we recognize the lines following a git header */
798 static int parse_git_header(char *line, int len, unsigned int size, struct patch *patch)
799 {
800         unsigned long offset;
801
802         /* A git diff has explicit new/delete information, so we don't guess */
803         patch->is_new = 0;
804         patch->is_delete = 0;
805
806         /*
807          * Some things may not have the old name in the
808          * rest of the headers anywhere (pure mode changes,
809          * or removing or adding empty files), so we get
810          * the default name from the header.
811          */
812         patch->def_name = git_header_name(line, len);
813
814         line += len;
815         size -= len;
816         linenr++;
817         for (offset = len ; size > 0 ; offset += len, size -= len, line += len, linenr++) {
818                 static const struct opentry {
819                         const char *str;
820                         int (*fn)(const char *, struct patch *);
821                 } optable[] = {
822                         { "@@ -", gitdiff_hdrend },
823                         { "--- ", gitdiff_oldname },
824                         { "+++ ", gitdiff_newname },
825                         { "old mode ", gitdiff_oldmode },
826                         { "new mode ", gitdiff_newmode },
827                         { "deleted file mode ", gitdiff_delete },
828                         { "new file mode ", gitdiff_newfile },
829                         { "copy from ", gitdiff_copysrc },
830                         { "copy to ", gitdiff_copydst },
831                         { "rename old ", gitdiff_renamesrc },
832                         { "rename new ", gitdiff_renamedst },
833                         { "rename from ", gitdiff_renamesrc },
834                         { "rename to ", gitdiff_renamedst },
835                         { "similarity index ", gitdiff_similarity },
836                         { "dissimilarity index ", gitdiff_dissimilarity },
837                         { "index ", gitdiff_index },
838                         { "", gitdiff_unrecognized },
839                 };
840                 int i;
841
842                 len = linelen(line, size);
843                 if (!len || line[len-1] != '\n')
844                         break;
845                 for (i = 0; i < ARRAY_SIZE(optable); i++) {
846                         const struct opentry *p = optable + i;
847                         int oplen = strlen(p->str);
848                         if (len < oplen || memcmp(p->str, line, oplen))
849                                 continue;
850                         if (p->fn(line + oplen, patch) < 0)
851                                 return offset;
852                         break;
853                 }
854         }
855
856         return offset;
857 }
858
859 static int parse_num(const char *line, unsigned long *p)
860 {
861         char *ptr;
862
863         if (!isdigit(*line))
864                 return 0;
865         *p = strtoul(line, &ptr, 10);
866         return ptr - line;
867 }
868
869 static int parse_range(const char *line, int len, int offset, const char *expect,
870                        unsigned long *p1, unsigned long *p2)
871 {
872         int digits, ex;
873
874         if (offset < 0 || offset >= len)
875                 return -1;
876         line += offset;
877         len -= offset;
878
879         digits = parse_num(line, p1);
880         if (!digits)
881                 return -1;
882
883         offset += digits;
884         line += digits;
885         len -= digits;
886
887         *p2 = 1;
888         if (*line == ',') {
889                 digits = parse_num(line+1, p2);
890                 if (!digits)
891                         return -1;
892
893                 offset += digits+1;
894                 line += digits+1;
895                 len -= digits+1;
896         }
897
898         ex = strlen(expect);
899         if (ex > len)
900                 return -1;
901         if (memcmp(line, expect, ex))
902                 return -1;
903
904         return offset + ex;
905 }
906
907 static void recount_diff(char *line, int size, struct fragment *fragment)
908 {
909         int oldlines = 0, newlines = 0, ret = 0;
910
911         if (size < 1) {
912                 warning("recount: ignore empty hunk");
913                 return;
914         }
915
916         for (;;) {
917                 int len = linelen(line, size);
918                 size -= len;
919                 line += len;
920
921                 if (size < 1)
922                         break;
923
924                 switch (*line) {
925                 case ' ': case '\n':
926                         newlines++;
927                         /* fall through */
928                 case '-':
929                         oldlines++;
930                         continue;
931                 case '+':
932                         newlines++;
933                         continue;
934                 case '\\':
935                         continue;
936                 case '@':
937                         ret = size < 3 || prefixcmp(line, "@@ ");
938                         break;
939                 case 'd':
940                         ret = size < 5 || prefixcmp(line, "diff ");
941                         break;
942                 default:
943                         ret = -1;
944                         break;
945                 }
946                 if (ret) {
947                         warning("recount: unexpected line: %.*s",
948                                 (int)linelen(line, size), line);
949                         return;
950                 }
951                 break;
952         }
953         fragment->oldlines = oldlines;
954         fragment->newlines = newlines;
955 }
956
957 /*
958  * Parse a unified diff fragment header of the
959  * form "@@ -a,b +c,d @@"
960  */
961 static int parse_fragment_header(char *line, int len, struct fragment *fragment)
962 {
963         int offset;
964
965         if (!len || line[len-1] != '\n')
966                 return -1;
967
968         /* Figure out the number of lines in a fragment */
969         offset = parse_range(line, len, 4, " +", &fragment->oldpos, &fragment->oldlines);
970         offset = parse_range(line, len, offset, " @@", &fragment->newpos, &fragment->newlines);
971
972         return offset;
973 }
974
975 static int find_header(char *line, unsigned long size, int *hdrsize, struct patch *patch)
976 {
977         unsigned long offset, len;
978
979         patch->is_toplevel_relative = 0;
980         patch->is_rename = patch->is_copy = 0;
981         patch->is_new = patch->is_delete = -1;
982         patch->old_mode = patch->new_mode = 0;
983         patch->old_name = patch->new_name = NULL;
984         for (offset = 0; size > 0; offset += len, size -= len, line += len, linenr++) {
985                 unsigned long nextlen;
986
987                 len = linelen(line, size);
988                 if (!len)
989                         break;
990
991                 /* Testing this early allows us to take a few shortcuts.. */
992                 if (len < 6)
993                         continue;
994
995                 /*
996                  * Make sure we don't find any unconnected patch fragments.
997                  * That's a sign that we didn't find a header, and that a
998                  * patch has become corrupted/broken up.
999                  */
1000                 if (!memcmp("@@ -", line, 4)) {
1001                         struct fragment dummy;
1002                         if (parse_fragment_header(line, len, &dummy) < 0)
1003                                 continue;
1004                         die("patch fragment without header at line %d: %.*s",
1005                             linenr, (int)len-1, line);
1006                 }
1007
1008                 if (size < len + 6)
1009                         break;
1010
1011                 /*
1012                  * Git patch? It might not have a real patch, just a rename
1013                  * or mode change, so we handle that specially
1014                  */
1015                 if (!memcmp("diff --git ", line, 11)) {
1016                         int git_hdr_len = parse_git_header(line, len, size, patch);
1017                         if (git_hdr_len <= len)
1018                                 continue;
1019                         if (!patch->old_name && !patch->new_name) {
1020                                 if (!patch->def_name)
1021                                         die("git diff header lacks filename information (line %d)", linenr);
1022                                 patch->old_name = patch->new_name = patch->def_name;
1023                         }
1024                         patch->is_toplevel_relative = 1;
1025                         *hdrsize = git_hdr_len;
1026                         return offset;
1027                 }
1028
1029                 /* --- followed by +++ ? */
1030                 if (memcmp("--- ", line,  4) || memcmp("+++ ", line + len, 4))
1031                         continue;
1032
1033                 /*
1034                  * We only accept unified patches, so we want it to
1035                  * at least have "@@ -a,b +c,d @@\n", which is 14 chars
1036                  * minimum ("@@ -0,0 +1 @@\n" is the shortest).
1037                  */
1038                 nextlen = linelen(line + len, size - len);
1039                 if (size < nextlen + 14 || memcmp("@@ -", line + len + nextlen, 4))
1040                         continue;
1041
1042                 /* Ok, we'll consider it a patch */
1043                 parse_traditional_patch(line, line+len, patch);
1044                 *hdrsize = len + nextlen;
1045                 linenr += 2;
1046                 return offset;
1047         }
1048         return -1;
1049 }
1050
1051 static void check_whitespace(const char *line, int len, unsigned ws_rule)
1052 {
1053         char *err;
1054         unsigned result = ws_check(line + 1, len - 1, ws_rule);
1055         if (!result)
1056                 return;
1057
1058         whitespace_error++;
1059         if (squelch_whitespace_errors &&
1060             squelch_whitespace_errors < whitespace_error)
1061                 ;
1062         else {
1063                 err = whitespace_error_string(result);
1064                 fprintf(stderr, "%s:%d: %s.\n%.*s\n",
1065                         patch_input_file, linenr, err, len - 2, line + 1);
1066                 free(err);
1067         }
1068 }
1069
1070 /*
1071  * Parse a unified diff. Note that this really needs to parse each
1072  * fragment separately, since the only way to know the difference
1073  * between a "---" that is part of a patch, and a "---" that starts
1074  * the next patch is to look at the line counts..
1075  */
1076 static int parse_fragment(char *line, unsigned long size,
1077                           struct patch *patch, struct fragment *fragment)
1078 {
1079         int added, deleted;
1080         int len = linelen(line, size), offset;
1081         unsigned long oldlines, newlines;
1082         unsigned long leading, trailing;
1083
1084         offset = parse_fragment_header(line, len, fragment);
1085         if (offset < 0)
1086                 return -1;
1087         if (offset > 0 && patch->recount)
1088                 recount_diff(line + offset, size - offset, fragment);
1089         oldlines = fragment->oldlines;
1090         newlines = fragment->newlines;
1091         leading = 0;
1092         trailing = 0;
1093
1094         /* Parse the thing.. */
1095         line += len;
1096         size -= len;
1097         linenr++;
1098         added = deleted = 0;
1099         for (offset = len;
1100              0 < size;
1101              offset += len, size -= len, line += len, linenr++) {
1102                 if (!oldlines && !newlines)
1103                         break;
1104                 len = linelen(line, size);
1105                 if (!len || line[len-1] != '\n')
1106                         return -1;
1107                 switch (*line) {
1108                 default:
1109                         return -1;
1110                 case '\n': /* newer GNU diff, an empty context line */
1111                 case ' ':
1112                         oldlines--;
1113                         newlines--;
1114                         if (!deleted && !added)
1115                                 leading++;
1116                         trailing++;
1117                         break;
1118                 case '-':
1119                         if (apply_in_reverse &&
1120                             ws_error_action != nowarn_ws_error)
1121                                 check_whitespace(line, len, patch->ws_rule);
1122                         deleted++;
1123                         oldlines--;
1124                         trailing = 0;
1125                         break;
1126                 case '+':
1127                         if (!apply_in_reverse &&
1128                             ws_error_action != nowarn_ws_error)
1129                                 check_whitespace(line, len, patch->ws_rule);
1130                         added++;
1131                         newlines--;
1132                         trailing = 0;
1133                         break;
1134
1135                 /*
1136                  * We allow "\ No newline at end of file". Depending
1137                  * on locale settings when the patch was produced we
1138                  * don't know what this line looks like. The only
1139                  * thing we do know is that it begins with "\ ".
1140                  * Checking for 12 is just for sanity check -- any
1141                  * l10n of "\ No newline..." is at least that long.
1142                  */
1143                 case '\\':
1144                         if (len < 12 || memcmp(line, "\\ ", 2))
1145                                 return -1;
1146                         break;
1147                 }
1148         }
1149         if (oldlines || newlines)
1150                 return -1;
1151         fragment->leading = leading;
1152         fragment->trailing = trailing;
1153
1154         /*
1155          * If a fragment ends with an incomplete line, we failed to include
1156          * it in the above loop because we hit oldlines == newlines == 0
1157          * before seeing it.
1158          */
1159         if (12 < size && !memcmp(line, "\\ ", 2))
1160                 offset += linelen(line, size);
1161
1162         patch->lines_added += added;
1163         patch->lines_deleted += deleted;
1164
1165         if (0 < patch->is_new && oldlines)
1166                 return error("new file depends on old contents");
1167         if (0 < patch->is_delete && newlines)
1168                 return error("deleted file still has contents");
1169         return offset;
1170 }
1171
1172 static int parse_single_patch(char *line, unsigned long size, struct patch *patch)
1173 {
1174         unsigned long offset = 0;
1175         unsigned long oldlines = 0, newlines = 0, context = 0;
1176         struct fragment **fragp = &patch->fragments;
1177
1178         while (size > 4 && !memcmp(line, "@@ -", 4)) {
1179                 struct fragment *fragment;
1180                 int len;
1181
1182                 fragment = xcalloc(1, sizeof(*fragment));
1183                 len = parse_fragment(line, size, patch, fragment);
1184                 if (len <= 0)
1185                         die("corrupt patch at line %d", linenr);
1186                 fragment->patch = line;
1187                 fragment->size = len;
1188                 oldlines += fragment->oldlines;
1189                 newlines += fragment->newlines;
1190                 context += fragment->leading + fragment->trailing;
1191
1192                 *fragp = fragment;
1193                 fragp = &fragment->next;
1194
1195                 offset += len;
1196                 line += len;
1197                 size -= len;
1198         }
1199
1200         /*
1201          * If something was removed (i.e. we have old-lines) it cannot
1202          * be creation, and if something was added it cannot be
1203          * deletion.  However, the reverse is not true; --unified=0
1204          * patches that only add are not necessarily creation even
1205          * though they do not have any old lines, and ones that only
1206          * delete are not necessarily deletion.
1207          *
1208          * Unfortunately, a real creation/deletion patch do _not_ have
1209          * any context line by definition, so we cannot safely tell it
1210          * apart with --unified=0 insanity.  At least if the patch has
1211          * more than one hunk it is not creation or deletion.
1212          */
1213         if (patch->is_new < 0 &&
1214             (oldlines || (patch->fragments && patch->fragments->next)))
1215                 patch->is_new = 0;
1216         if (patch->is_delete < 0 &&
1217             (newlines || (patch->fragments && patch->fragments->next)))
1218                 patch->is_delete = 0;
1219
1220         if (0 < patch->is_new && oldlines)
1221                 die("new file %s depends on old contents", patch->new_name);
1222         if (0 < patch->is_delete && newlines)
1223                 die("deleted file %s still has contents", patch->old_name);
1224         if (!patch->is_delete && !newlines && context)
1225                 fprintf(stderr, "** warning: file %s becomes empty but "
1226                         "is not deleted\n", patch->new_name);
1227
1228         return offset;
1229 }
1230
1231 static inline int metadata_changes(struct patch *patch)
1232 {
1233         return  patch->is_rename > 0 ||
1234                 patch->is_copy > 0 ||
1235                 patch->is_new > 0 ||
1236                 patch->is_delete ||
1237                 (patch->old_mode && patch->new_mode &&
1238                  patch->old_mode != patch->new_mode);
1239 }
1240
1241 static char *inflate_it(const void *data, unsigned long size,
1242                         unsigned long inflated_size)
1243 {
1244         z_stream stream;
1245         void *out;
1246         int st;
1247
1248         memset(&stream, 0, sizeof(stream));
1249
1250         stream.next_in = (unsigned char *)data;
1251         stream.avail_in = size;
1252         stream.next_out = out = xmalloc(inflated_size);
1253         stream.avail_out = inflated_size;
1254         inflateInit(&stream);
1255         st = inflate(&stream, Z_FINISH);
1256         if ((st != Z_STREAM_END) || stream.total_out != inflated_size) {
1257                 free(out);
1258                 return NULL;
1259         }
1260         return out;
1261 }
1262
1263 static struct fragment *parse_binary_hunk(char **buf_p,
1264                                           unsigned long *sz_p,
1265                                           int *status_p,
1266                                           int *used_p)
1267 {
1268         /*
1269          * Expect a line that begins with binary patch method ("literal"
1270          * or "delta"), followed by the length of data before deflating.
1271          * a sequence of 'length-byte' followed by base-85 encoded data
1272          * should follow, terminated by a newline.
1273          *
1274          * Each 5-byte sequence of base-85 encodes up to 4 bytes,
1275          * and we would limit the patch line to 66 characters,
1276          * so one line can fit up to 13 groups that would decode
1277          * to 52 bytes max.  The length byte 'A'-'Z' corresponds
1278          * to 1-26 bytes, and 'a'-'z' corresponds to 27-52 bytes.
1279          */
1280         int llen, used;
1281         unsigned long size = *sz_p;
1282         char *buffer = *buf_p;
1283         int patch_method;
1284         unsigned long origlen;
1285         char *data = NULL;
1286         int hunk_size = 0;
1287         struct fragment *frag;
1288
1289         llen = linelen(buffer, size);
1290         used = llen;
1291
1292         *status_p = 0;
1293
1294         if (!prefixcmp(buffer, "delta ")) {
1295                 patch_method = BINARY_DELTA_DEFLATED;
1296                 origlen = strtoul(buffer + 6, NULL, 10);
1297         }
1298         else if (!prefixcmp(buffer, "literal ")) {
1299                 patch_method = BINARY_LITERAL_DEFLATED;
1300                 origlen = strtoul(buffer + 8, NULL, 10);
1301         }
1302         else
1303                 return NULL;
1304
1305         linenr++;
1306         buffer += llen;
1307         while (1) {
1308                 int byte_length, max_byte_length, newsize;
1309                 llen = linelen(buffer, size);
1310                 used += llen;
1311                 linenr++;
1312                 if (llen == 1) {
1313                         /* consume the blank line */
1314                         buffer++;
1315                         size--;
1316                         break;
1317                 }
1318                 /*
1319                  * Minimum line is "A00000\n" which is 7-byte long,
1320                  * and the line length must be multiple of 5 plus 2.
1321                  */
1322                 if ((llen < 7) || (llen-2) % 5)
1323                         goto corrupt;
1324                 max_byte_length = (llen - 2) / 5 * 4;
1325                 byte_length = *buffer;
1326                 if ('A' <= byte_length && byte_length <= 'Z')
1327                         byte_length = byte_length - 'A' + 1;
1328                 else if ('a' <= byte_length && byte_length <= 'z')
1329                         byte_length = byte_length - 'a' + 27;
1330                 else
1331                         goto corrupt;
1332                 /* if the input length was not multiple of 4, we would
1333                  * have filler at the end but the filler should never
1334                  * exceed 3 bytes
1335                  */
1336                 if (max_byte_length < byte_length ||
1337                     byte_length <= max_byte_length - 4)
1338                         goto corrupt;
1339                 newsize = hunk_size + byte_length;
1340                 data = xrealloc(data, newsize);
1341                 if (decode_85(data + hunk_size, buffer + 1, byte_length))
1342                         goto corrupt;
1343                 hunk_size = newsize;
1344                 buffer += llen;
1345                 size -= llen;
1346         }
1347
1348         frag = xcalloc(1, sizeof(*frag));
1349         frag->patch = inflate_it(data, hunk_size, origlen);
1350         if (!frag->patch)
1351                 goto corrupt;
1352         free(data);
1353         frag->size = origlen;
1354         *buf_p = buffer;
1355         *sz_p = size;
1356         *used_p = used;
1357         frag->binary_patch_method = patch_method;
1358         return frag;
1359
1360  corrupt:
1361         free(data);
1362         *status_p = -1;
1363         error("corrupt binary patch at line %d: %.*s",
1364               linenr-1, llen-1, buffer);
1365         return NULL;
1366 }
1367
1368 static int parse_binary(char *buffer, unsigned long size, struct patch *patch)
1369 {
1370         /*
1371          * We have read "GIT binary patch\n"; what follows is a line
1372          * that says the patch method (currently, either "literal" or
1373          * "delta") and the length of data before deflating; a
1374          * sequence of 'length-byte' followed by base-85 encoded data
1375          * follows.
1376          *
1377          * When a binary patch is reversible, there is another binary
1378          * hunk in the same format, starting with patch method (either
1379          * "literal" or "delta") with the length of data, and a sequence
1380          * of length-byte + base-85 encoded data, terminated with another
1381          * empty line.  This data, when applied to the postimage, produces
1382          * the preimage.
1383          */
1384         struct fragment *forward;
1385         struct fragment *reverse;
1386         int status;
1387         int used, used_1;
1388
1389         forward = parse_binary_hunk(&buffer, &size, &status, &used);
1390         if (!forward && !status)
1391                 /* there has to be one hunk (forward hunk) */
1392                 return error("unrecognized binary patch at line %d", linenr-1);
1393         if (status)
1394                 /* otherwise we already gave an error message */
1395                 return status;
1396
1397         reverse = parse_binary_hunk(&buffer, &size, &status, &used_1);
1398         if (reverse)
1399                 used += used_1;
1400         else if (status) {
1401                 /*
1402                  * Not having reverse hunk is not an error, but having
1403                  * a corrupt reverse hunk is.
1404                  */
1405                 free((void*) forward->patch);
1406                 free(forward);
1407                 return status;
1408         }
1409         forward->next = reverse;
1410         patch->fragments = forward;
1411         patch->is_binary = 1;
1412         return used;
1413 }
1414
1415 static int parse_chunk(char *buffer, unsigned long size, struct patch *patch)
1416 {
1417         int hdrsize, patchsize;
1418         int offset = find_header(buffer, size, &hdrsize, patch);
1419
1420         if (offset < 0)
1421                 return offset;
1422
1423         patch->ws_rule = whitespace_rule(patch->new_name
1424                                          ? patch->new_name
1425                                          : patch->old_name);
1426
1427         patchsize = parse_single_patch(buffer + offset + hdrsize,
1428                                        size - offset - hdrsize, patch);
1429
1430         if (!patchsize) {
1431                 static const char *binhdr[] = {
1432                         "Binary files ",
1433                         "Files ",
1434                         NULL,
1435                 };
1436                 static const char git_binary[] = "GIT binary patch\n";
1437                 int i;
1438                 int hd = hdrsize + offset;
1439                 unsigned long llen = linelen(buffer + hd, size - hd);
1440
1441                 if (llen == sizeof(git_binary) - 1 &&
1442                     !memcmp(git_binary, buffer + hd, llen)) {
1443                         int used;
1444                         linenr++;
1445                         used = parse_binary(buffer + hd + llen,
1446                                             size - hd - llen, patch);
1447                         if (used)
1448                                 patchsize = used + llen;
1449                         else
1450                                 patchsize = 0;
1451                 }
1452                 else if (!memcmp(" differ\n", buffer + hd + llen - 8, 8)) {
1453                         for (i = 0; binhdr[i]; i++) {
1454                                 int len = strlen(binhdr[i]);
1455                                 if (len < size - hd &&
1456                                     !memcmp(binhdr[i], buffer + hd, len)) {
1457                                         linenr++;
1458                                         patch->is_binary = 1;
1459                                         patchsize = llen;
1460                                         break;
1461                                 }
1462                         }
1463                 }
1464
1465                 /* Empty patch cannot be applied if it is a text patch
1466                  * without metadata change.  A binary patch appears
1467                  * empty to us here.
1468                  */
1469                 if ((apply || check) &&
1470                     (!patch->is_binary && !metadata_changes(patch)))
1471                         die("patch with only garbage at line %d", linenr);
1472         }
1473
1474         return offset + hdrsize + patchsize;
1475 }
1476
1477 #define swap(a,b) myswap((a),(b),sizeof(a))
1478
1479 #define myswap(a, b, size) do {         \
1480         unsigned char mytmp[size];      \
1481         memcpy(mytmp, &a, size);                \
1482         memcpy(&a, &b, size);           \
1483         memcpy(&b, mytmp, size);                \
1484 } while (0)
1485
1486 static void reverse_patches(struct patch *p)
1487 {
1488         for (; p; p = p->next) {
1489                 struct fragment *frag = p->fragments;
1490
1491                 swap(p->new_name, p->old_name);
1492                 swap(p->new_mode, p->old_mode);
1493                 swap(p->is_new, p->is_delete);
1494                 swap(p->lines_added, p->lines_deleted);
1495                 swap(p->old_sha1_prefix, p->new_sha1_prefix);
1496
1497                 for (; frag; frag = frag->next) {
1498                         swap(frag->newpos, frag->oldpos);
1499                         swap(frag->newlines, frag->oldlines);
1500                 }
1501         }
1502 }
1503
1504 static const char pluses[] =
1505 "++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++";
1506 static const char minuses[]=
1507 "----------------------------------------------------------------------";
1508
1509 static void show_stats(struct patch *patch)
1510 {
1511         struct strbuf qname;
1512         char *cp = patch->new_name ? patch->new_name : patch->old_name;
1513         int max, add, del;
1514
1515         strbuf_init(&qname, 0);
1516         quote_c_style(cp, &qname, NULL, 0);
1517
1518         /*
1519          * "scale" the filename
1520          */
1521         max = max_len;
1522         if (max > 50)
1523                 max = 50;
1524
1525         if (qname.len > max) {
1526                 cp = strchr(qname.buf + qname.len + 3 - max, '/');
1527                 if (!cp)
1528                         cp = qname.buf + qname.len + 3 - max;
1529                 strbuf_splice(&qname, 0, cp - qname.buf, "...", 3);
1530         }
1531
1532         if (patch->is_binary) {
1533                 printf(" %-*s |  Bin\n", max, qname.buf);
1534                 strbuf_release(&qname);
1535                 return;
1536         }
1537
1538         printf(" %-*s |", max, qname.buf);
1539         strbuf_release(&qname);
1540
1541         /*
1542          * scale the add/delete
1543          */
1544         max = max + max_change > 70 ? 70 - max : max_change;
1545         add = patch->lines_added;
1546         del = patch->lines_deleted;
1547
1548         if (max_change > 0) {
1549                 int total = ((add + del) * max + max_change / 2) / max_change;
1550                 add = (add * max + max_change / 2) / max_change;
1551                 del = total - add;
1552         }
1553         printf("%5d %.*s%.*s\n", patch->lines_added + patch->lines_deleted,
1554                 add, pluses, del, minuses);
1555 }
1556
1557 static int read_old_data(struct stat *st, const char *path, struct strbuf *buf)
1558 {
1559         switch (st->st_mode & S_IFMT) {
1560         case S_IFLNK:
1561                 strbuf_grow(buf, st->st_size);
1562                 if (readlink(path, buf->buf, st->st_size) != st->st_size)
1563                         return -1;
1564                 strbuf_setlen(buf, st->st_size);
1565                 return 0;
1566         case S_IFREG:
1567                 if (strbuf_read_file(buf, path, st->st_size) != st->st_size)
1568                         return error("unable to open or read %s", path);
1569                 convert_to_git(path, buf->buf, buf->len, buf, 0);
1570                 return 0;
1571         default:
1572                 return -1;
1573         }
1574 }
1575
1576 static void update_pre_post_images(struct image *preimage,
1577                                    struct image *postimage,
1578                                    char *buf,
1579                                    size_t len)
1580 {
1581         int i, ctx;
1582         char *new, *old, *fixed;
1583         struct image fixed_preimage;
1584
1585         /*
1586          * Update the preimage with whitespace fixes.  Note that we
1587          * are not losing preimage->buf -- apply_one_fragment() will
1588          * free "oldlines".
1589          */
1590         prepare_image(&fixed_preimage, buf, len, 1);
1591         assert(fixed_preimage.nr == preimage->nr);
1592         for (i = 0; i < preimage->nr; i++)
1593                 fixed_preimage.line[i].flag = preimage->line[i].flag;
1594         free(preimage->line_allocated);
1595         *preimage = fixed_preimage;
1596
1597         /*
1598          * Adjust the common context lines in postimage, in place.
1599          * This is possible because whitespace fixing does not make
1600          * the string grow.
1601          */
1602         new = old = postimage->buf;
1603         fixed = preimage->buf;
1604         for (i = ctx = 0; i < postimage->nr; i++) {
1605                 size_t len = postimage->line[i].len;
1606                 if (!(postimage->line[i].flag & LINE_COMMON)) {
1607                         /* an added line -- no counterparts in preimage */
1608                         memmove(new, old, len);
1609                         old += len;
1610                         new += len;
1611                         continue;
1612                 }
1613
1614                 /* a common context -- skip it in the original postimage */
1615                 old += len;
1616
1617                 /* and find the corresponding one in the fixed preimage */
1618                 while (ctx < preimage->nr &&
1619                        !(preimage->line[ctx].flag & LINE_COMMON)) {
1620                         fixed += preimage->line[ctx].len;
1621                         ctx++;
1622                 }
1623                 if (preimage->nr <= ctx)
1624                         die("oops");
1625
1626                 /* and copy it in, while fixing the line length */
1627                 len = preimage->line[ctx].len;
1628                 memcpy(new, fixed, len);
1629                 new += len;
1630                 fixed += len;
1631                 postimage->line[i].len = len;
1632                 ctx++;
1633         }
1634
1635         /* Fix the length of the whole thing */
1636         postimage->len = new - postimage->buf;
1637 }
1638
1639 static int match_fragment(struct image *img,
1640                           struct image *preimage,
1641                           struct image *postimage,
1642                           unsigned long try,
1643                           int try_lno,
1644                           unsigned ws_rule,
1645                           int match_beginning, int match_end)
1646 {
1647         int i;
1648         char *fixed_buf, *buf, *orig, *target;
1649
1650         if (preimage->nr + try_lno > img->nr)
1651                 return 0;
1652
1653         if (match_beginning && try_lno)
1654                 return 0;
1655
1656         if (match_end && preimage->nr + try_lno != img->nr)
1657                 return 0;
1658
1659         /* Quick hash check */
1660         for (i = 0; i < preimage->nr; i++)
1661                 if (preimage->line[i].hash != img->line[try_lno + i].hash)
1662                         return 0;
1663
1664         /*
1665          * Do we have an exact match?  If we were told to match
1666          * at the end, size must be exactly at try+fragsize,
1667          * otherwise try+fragsize must be still within the preimage,
1668          * and either case, the old piece should match the preimage
1669          * exactly.
1670          */
1671         if ((match_end
1672              ? (try + preimage->len == img->len)
1673              : (try + preimage->len <= img->len)) &&
1674             !memcmp(img->buf + try, preimage->buf, preimage->len))
1675                 return 1;
1676
1677         if (ws_error_action != correct_ws_error)
1678                 return 0;
1679
1680         /*
1681          * The hunk does not apply byte-by-byte, but the hash says
1682          * it might with whitespace fuzz.
1683          */
1684         fixed_buf = xmalloc(preimage->len + 1);
1685         buf = fixed_buf;
1686         orig = preimage->buf;
1687         target = img->buf + try;
1688         for (i = 0; i < preimage->nr; i++) {
1689                 size_t fixlen; /* length after fixing the preimage */
1690                 size_t oldlen = preimage->line[i].len;
1691                 size_t tgtlen = img->line[try_lno + i].len;
1692                 size_t tgtfixlen; /* length after fixing the target line */
1693                 char tgtfixbuf[1024], *tgtfix;
1694                 int match;
1695
1696                 /* Try fixing the line in the preimage */
1697                 fixlen = ws_fix_copy(buf, orig, oldlen, ws_rule, NULL);
1698
1699                 /* Try fixing the line in the target */
1700                 if (sizeof(tgtfixbuf) < tgtlen)
1701                         tgtfix = tgtfixbuf;
1702                 else
1703                         tgtfix = xmalloc(tgtlen);
1704                 tgtfixlen = ws_fix_copy(tgtfix, target, tgtlen, ws_rule, NULL);
1705
1706                 /*
1707                  * If they match, either the preimage was based on
1708                  * a version before our tree fixed whitespace breakage,
1709                  * or we are lacking a whitespace-fix patch the tree
1710                  * the preimage was based on already had (i.e. target
1711                  * has whitespace breakage, the preimage doesn't).
1712                  * In either case, we are fixing the whitespace breakages
1713                  * so we might as well take the fix together with their
1714                  * real change.
1715                  */
1716                 match = (tgtfixlen == fixlen && !memcmp(tgtfix, buf, fixlen));
1717
1718                 if (tgtfix != tgtfixbuf)
1719                         free(tgtfix);
1720                 if (!match)
1721                         goto unmatch_exit;
1722
1723                 orig += oldlen;
1724                 buf += fixlen;
1725                 target += tgtlen;
1726         }
1727
1728         /*
1729          * Yes, the preimage is based on an older version that still
1730          * has whitespace breakages unfixed, and fixing them makes the
1731          * hunk match.  Update the context lines in the postimage.
1732          */
1733         update_pre_post_images(preimage, postimage,
1734                                fixed_buf, buf - fixed_buf);
1735         return 1;
1736
1737  unmatch_exit:
1738         free(fixed_buf);
1739         return 0;
1740 }
1741
1742 static int find_pos(struct image *img,
1743                     struct image *preimage,
1744                     struct image *postimage,
1745                     int line,
1746                     unsigned ws_rule,
1747                     int match_beginning, int match_end)
1748 {
1749         int i;
1750         unsigned long backwards, forwards, try;
1751         int backwards_lno, forwards_lno, try_lno;
1752
1753         if (preimage->nr > img->nr)
1754                 return -1;
1755
1756         /*
1757          * If match_begining or match_end is specified, there is no
1758          * point starting from a wrong line that will never match and
1759          * wander around and wait for a match at the specified end.
1760          */
1761         if (match_beginning)
1762                 line = 0;
1763         else if (match_end)
1764                 line = img->nr - preimage->nr;
1765
1766         if (line > img->nr)
1767                 line = img->nr;
1768
1769         try = 0;
1770         for (i = 0; i < line; i++)
1771                 try += img->line[i].len;
1772
1773         /*
1774          * There's probably some smart way to do this, but I'll leave
1775          * that to the smart and beautiful people. I'm simple and stupid.
1776          */
1777         backwards = try;
1778         backwards_lno = line;
1779         forwards = try;
1780         forwards_lno = line;
1781         try_lno = line;
1782
1783         for (i = 0; ; i++) {
1784                 if (match_fragment(img, preimage, postimage,
1785                                    try, try_lno, ws_rule,
1786                                    match_beginning, match_end))
1787                         return try_lno;
1788
1789         again:
1790                 if (backwards_lno == 0 && forwards_lno == img->nr)
1791                         break;
1792
1793                 if (i & 1) {
1794                         if (backwards_lno == 0) {
1795                                 i++;
1796                                 goto again;
1797                         }
1798                         backwards_lno--;
1799                         backwards -= img->line[backwards_lno].len;
1800                         try = backwards;
1801                         try_lno = backwards_lno;
1802                 } else {
1803                         if (forwards_lno == img->nr) {
1804                                 i++;
1805                                 goto again;
1806                         }
1807                         forwards += img->line[forwards_lno].len;
1808                         forwards_lno++;
1809                         try = forwards;
1810                         try_lno = forwards_lno;
1811                 }
1812
1813         }
1814         return -1;
1815 }
1816
1817 static void remove_first_line(struct image *img)
1818 {
1819         img->buf += img->line[0].len;
1820         img->len -= img->line[0].len;
1821         img->line++;
1822         img->nr--;
1823 }
1824
1825 static void remove_last_line(struct image *img)
1826 {
1827         img->len -= img->line[--img->nr].len;
1828 }
1829
1830 static void update_image(struct image *img,
1831                          int applied_pos,
1832                          struct image *preimage,
1833                          struct image *postimage)
1834 {
1835         /*
1836          * remove the copy of preimage at offset in img
1837          * and replace it with postimage
1838          */
1839         int i, nr;
1840         size_t remove_count, insert_count, applied_at = 0;
1841         char *result;
1842
1843         for (i = 0; i < applied_pos; i++)
1844                 applied_at += img->line[i].len;
1845
1846         remove_count = 0;
1847         for (i = 0; i < preimage->nr; i++)
1848                 remove_count += img->line[applied_pos + i].len;
1849         insert_count = postimage->len;
1850
1851         /* Adjust the contents */
1852         result = xmalloc(img->len + insert_count - remove_count + 1);
1853         memcpy(result, img->buf, applied_at);
1854         memcpy(result + applied_at, postimage->buf, postimage->len);
1855         memcpy(result + applied_at + postimage->len,
1856                img->buf + (applied_at + remove_count),
1857                img->len - (applied_at + remove_count));
1858         free(img->buf);
1859         img->buf = result;
1860         img->len += insert_count - remove_count;
1861         result[img->len] = '\0';
1862
1863         /* Adjust the line table */
1864         nr = img->nr + postimage->nr - preimage->nr;
1865         if (preimage->nr < postimage->nr) {
1866                 /*
1867                  * NOTE: this knows that we never call remove_first_line()
1868                  * on anything other than pre/post image.
1869                  */
1870                 img->line = xrealloc(img->line, nr * sizeof(*img->line));
1871                 img->line_allocated = img->line;
1872         }
1873         if (preimage->nr != postimage->nr)
1874                 memmove(img->line + applied_pos + postimage->nr,
1875                         img->line + applied_pos + preimage->nr,
1876                         (img->nr - (applied_pos + preimage->nr)) *
1877                         sizeof(*img->line));
1878         memcpy(img->line + applied_pos,
1879                postimage->line,
1880                postimage->nr * sizeof(*img->line));
1881         img->nr = nr;
1882 }
1883
1884 static int apply_one_fragment(struct image *img, struct fragment *frag,
1885                               int inaccurate_eof, unsigned ws_rule)
1886 {
1887         int match_beginning, match_end;
1888         const char *patch = frag->patch;
1889         int size = frag->size;
1890         char *old, *new, *oldlines, *newlines;
1891         int new_blank_lines_at_end = 0;
1892         unsigned long leading, trailing;
1893         int pos, applied_pos;
1894         struct image preimage;
1895         struct image postimage;
1896
1897         memset(&preimage, 0, sizeof(preimage));
1898         memset(&postimage, 0, sizeof(postimage));
1899         oldlines = xmalloc(size);
1900         newlines = xmalloc(size);
1901
1902         old = oldlines;
1903         new = newlines;
1904         while (size > 0) {
1905                 char first;
1906                 int len = linelen(patch, size);
1907                 int plen, added;
1908                 int added_blank_line = 0;
1909
1910                 if (!len)
1911                         break;
1912
1913                 /*
1914                  * "plen" is how much of the line we should use for
1915                  * the actual patch data. Normally we just remove the
1916                  * first character on the line, but if the line is
1917                  * followed by "\ No newline", then we also remove the
1918                  * last one (which is the newline, of course).
1919                  */
1920                 plen = len - 1;
1921                 if (len < size && patch[len] == '\\')
1922                         plen--;
1923                 first = *patch;
1924                 if (apply_in_reverse) {
1925                         if (first == '-')
1926                                 first = '+';
1927                         else if (first == '+')
1928                                 first = '-';
1929                 }
1930
1931                 switch (first) {
1932                 case '\n':
1933                         /* Newer GNU diff, empty context line */
1934                         if (plen < 0)
1935                                 /* ... followed by '\No newline'; nothing */
1936                                 break;
1937                         *old++ = '\n';
1938                         *new++ = '\n';
1939                         add_line_info(&preimage, "\n", 1, LINE_COMMON);
1940                         add_line_info(&postimage, "\n", 1, LINE_COMMON);
1941                         break;
1942                 case ' ':
1943                 case '-':
1944                         memcpy(old, patch + 1, plen);
1945                         add_line_info(&preimage, old, plen,
1946                                       (first == ' ' ? LINE_COMMON : 0));
1947                         old += plen;
1948                         if (first == '-')
1949                                 break;
1950                 /* Fall-through for ' ' */
1951                 case '+':
1952                         /* --no-add does not add new lines */
1953                         if (first == '+' && no_add)
1954                                 break;
1955
1956                         if (first != '+' ||
1957                             !whitespace_error ||
1958                             ws_error_action != correct_ws_error) {
1959                                 memcpy(new, patch + 1, plen);
1960                                 added = plen;
1961                         }
1962                         else {
1963                                 added = ws_fix_copy(new, patch + 1, plen, ws_rule, &applied_after_fixing_ws);
1964                         }
1965                         add_line_info(&postimage, new, added,
1966                                       (first == '+' ? 0 : LINE_COMMON));
1967                         new += added;
1968                         if (first == '+' &&
1969                             added == 1 && new[-1] == '\n')
1970                                 added_blank_line = 1;
1971                         break;
1972                 case '@': case '\\':
1973                         /* Ignore it, we already handled it */
1974                         break;
1975                 default:
1976                         if (apply_verbosely)
1977                                 error("invalid start of line: '%c'", first);
1978                         return -1;
1979                 }
1980                 if (added_blank_line)
1981                         new_blank_lines_at_end++;
1982                 else
1983                         new_blank_lines_at_end = 0;
1984                 patch += len;
1985                 size -= len;
1986         }
1987         if (inaccurate_eof &&
1988             old > oldlines && old[-1] == '\n' &&
1989             new > newlines && new[-1] == '\n') {
1990                 old--;
1991                 new--;
1992         }
1993
1994         leading = frag->leading;
1995         trailing = frag->trailing;
1996
1997         /*
1998          * A hunk to change lines at the beginning would begin with
1999          * @@ -1,L +N,M @@
2000          * but we need to be careful.  -U0 that inserts before the second
2001          * line also has this pattern.
2002          *
2003          * And a hunk to add to an empty file would begin with
2004          * @@ -0,0 +N,M @@
2005          *
2006          * In other words, a hunk that is (frag->oldpos <= 1) with or
2007          * without leading context must match at the beginning.
2008          */
2009         match_beginning = (!frag->oldpos ||
2010                            (frag->oldpos == 1 && !unidiff_zero));
2011
2012         /*
2013          * A hunk without trailing lines must match at the end.
2014          * However, we simply cannot tell if a hunk must match end
2015          * from the lack of trailing lines if the patch was generated
2016          * with unidiff without any context.
2017          */
2018         match_end = !unidiff_zero && !trailing;
2019
2020         pos = frag->newpos ? (frag->newpos - 1) : 0;
2021         preimage.buf = oldlines;
2022         preimage.len = old - oldlines;
2023         postimage.buf = newlines;
2024         postimage.len = new - newlines;
2025         preimage.line = preimage.line_allocated;
2026         postimage.line = postimage.line_allocated;
2027
2028         for (;;) {
2029
2030                 applied_pos = find_pos(img, &preimage, &postimage, pos,
2031                                        ws_rule, match_beginning, match_end);
2032
2033                 if (applied_pos >= 0)
2034                         break;
2035
2036                 /* Am I at my context limits? */
2037                 if ((leading <= p_context) && (trailing <= p_context))
2038                         break;
2039                 if (match_beginning || match_end) {
2040                         match_beginning = match_end = 0;
2041                         continue;
2042                 }
2043
2044                 /*
2045                  * Reduce the number of context lines; reduce both
2046                  * leading and trailing if they are equal otherwise
2047                  * just reduce the larger context.
2048                  */
2049                 if (leading >= trailing) {
2050                         remove_first_line(&preimage);
2051                         remove_first_line(&postimage);
2052                         pos--;
2053                         leading--;
2054                 }
2055                 if (trailing > leading) {
2056                         remove_last_line(&preimage);
2057                         remove_last_line(&postimage);
2058                         trailing--;
2059                 }
2060         }
2061
2062         if (applied_pos >= 0) {
2063                 if (ws_error_action == correct_ws_error &&
2064                     new_blank_lines_at_end &&
2065                     postimage.nr + applied_pos == img->nr) {
2066                         /*
2067                          * If the patch application adds blank lines
2068                          * at the end, and if the patch applies at the
2069                          * end of the image, remove those added blank
2070                          * lines.
2071                          */
2072                         while (new_blank_lines_at_end--)
2073                                 remove_last_line(&postimage);
2074                 }
2075
2076                 /*
2077                  * Warn if it was necessary to reduce the number
2078                  * of context lines.
2079                  */
2080                 if ((leading != frag->leading) ||
2081                     (trailing != frag->trailing))
2082                         fprintf(stderr, "Context reduced to (%ld/%ld)"
2083                                 " to apply fragment at %d\n",
2084                                 leading, trailing, applied_pos+1);
2085                 update_image(img, applied_pos, &preimage, &postimage);
2086         } else {
2087                 if (apply_verbosely)
2088                         error("while searching for:\n%.*s",
2089                               (int)(old - oldlines), oldlines);
2090         }
2091
2092         free(oldlines);
2093         free(newlines);
2094         free(preimage.line_allocated);
2095         free(postimage.line_allocated);
2096
2097         return (applied_pos < 0);
2098 }
2099
2100 static int apply_binary_fragment(struct image *img, struct patch *patch)
2101 {
2102         struct fragment *fragment = patch->fragments;
2103         unsigned long len;
2104         void *dst;
2105
2106         /* Binary patch is irreversible without the optional second hunk */
2107         if (apply_in_reverse) {
2108                 if (!fragment->next)
2109                         return error("cannot reverse-apply a binary patch "
2110                                      "without the reverse hunk to '%s'",
2111                                      patch->new_name
2112                                      ? patch->new_name : patch->old_name);
2113                 fragment = fragment->next;
2114         }
2115         switch (fragment->binary_patch_method) {
2116         case BINARY_DELTA_DEFLATED:
2117                 dst = patch_delta(img->buf, img->len, fragment->patch,
2118                                   fragment->size, &len);
2119                 if (!dst)
2120                         return -1;
2121                 clear_image(img);
2122                 img->buf = dst;
2123                 img->len = len;
2124                 return 0;
2125         case BINARY_LITERAL_DEFLATED:
2126                 clear_image(img);
2127                 img->len = fragment->size;
2128                 img->buf = xmalloc(img->len+1);
2129                 memcpy(img->buf, fragment->patch, img->len);
2130                 img->buf[img->len] = '\0';
2131                 return 0;
2132         }
2133         return -1;
2134 }
2135
2136 static int apply_binary(struct image *img, struct patch *patch)
2137 {
2138         const char *name = patch->old_name ? patch->old_name : patch->new_name;
2139         unsigned char sha1[20];
2140
2141         /*
2142          * For safety, we require patch index line to contain
2143          * full 40-byte textual SHA1 for old and new, at least for now.
2144          */
2145         if (strlen(patch->old_sha1_prefix) != 40 ||
2146             strlen(patch->new_sha1_prefix) != 40 ||
2147             get_sha1_hex(patch->old_sha1_prefix, sha1) ||
2148             get_sha1_hex(patch->new_sha1_prefix, sha1))
2149                 return error("cannot apply binary patch to '%s' "
2150                              "without full index line", name);
2151
2152         if (patch->old_name) {
2153                 /*
2154                  * See if the old one matches what the patch
2155                  * applies to.
2156                  */
2157                 hash_sha1_file(img->buf, img->len, blob_type, sha1);
2158                 if (strcmp(sha1_to_hex(sha1), patch->old_sha1_prefix))
2159                         return error("the patch applies to '%s' (%s), "
2160                                      "which does not match the "
2161                                      "current contents.",
2162                                      name, sha1_to_hex(sha1));
2163         }
2164         else {
2165                 /* Otherwise, the old one must be empty. */
2166                 if (img->len)
2167                         return error("the patch applies to an empty "
2168                                      "'%s' but it is not empty", name);
2169         }
2170
2171         get_sha1_hex(patch->new_sha1_prefix, sha1);
2172         if (is_null_sha1(sha1)) {
2173                 clear_image(img);
2174                 return 0; /* deletion patch */
2175         }
2176
2177         if (has_sha1_file(sha1)) {
2178                 /* We already have the postimage */
2179                 enum object_type type;
2180                 unsigned long size;
2181                 char *result;
2182
2183                 result = read_sha1_file(sha1, &type, &size);
2184                 if (!result)
2185                         return error("the necessary postimage %s for "
2186                                      "'%s' cannot be read",
2187                                      patch->new_sha1_prefix, name);
2188                 clear_image(img);
2189                 img->buf = result;
2190                 img->len = size;
2191         } else {
2192                 /*
2193                  * We have verified buf matches the preimage;
2194                  * apply the patch data to it, which is stored
2195                  * in the patch->fragments->{patch,size}.
2196                  */
2197                 if (apply_binary_fragment(img, patch))
2198                         return error("binary patch does not apply to '%s'",
2199                                      name);
2200
2201                 /* verify that the result matches */
2202                 hash_sha1_file(img->buf, img->len, blob_type, sha1);
2203                 if (strcmp(sha1_to_hex(sha1), patch->new_sha1_prefix))
2204                         return error("binary patch to '%s' creates incorrect result (expecting %s, got %s)",
2205                                 name, patch->new_sha1_prefix, sha1_to_hex(sha1));
2206         }
2207
2208         return 0;
2209 }
2210
2211 static int apply_fragments(struct image *img, struct patch *patch)
2212 {
2213         struct fragment *frag = patch->fragments;
2214         const char *name = patch->old_name ? patch->old_name : patch->new_name;
2215         unsigned ws_rule = patch->ws_rule;
2216         unsigned inaccurate_eof = patch->inaccurate_eof;
2217
2218         if (patch->is_binary)
2219                 return apply_binary(img, patch);
2220
2221         while (frag) {
2222                 if (apply_one_fragment(img, frag, inaccurate_eof, ws_rule)) {
2223                         error("patch failed: %s:%ld", name, frag->oldpos);
2224                         if (!apply_with_reject)
2225                                 return -1;
2226                         frag->rejected = 1;
2227                 }
2228                 frag = frag->next;
2229         }
2230         return 0;
2231 }
2232
2233 static int read_file_or_gitlink(struct cache_entry *ce, struct strbuf *buf)
2234 {
2235         if (!ce)
2236                 return 0;
2237
2238         if (S_ISGITLINK(ce->ce_mode)) {
2239                 strbuf_grow(buf, 100);
2240                 strbuf_addf(buf, "Subproject commit %s\n", sha1_to_hex(ce->sha1));
2241         } else {
2242                 enum object_type type;
2243                 unsigned long sz;
2244                 char *result;
2245
2246                 result = read_sha1_file(ce->sha1, &type, &sz);
2247                 if (!result)
2248                         return -1;
2249                 /* XXX read_sha1_file NUL-terminates */
2250                 strbuf_attach(buf, result, sz, sz + 1);
2251         }
2252         return 0;
2253 }
2254
2255 static struct patch *in_fn_table(const char *name)
2256 {
2257         struct string_list_item *item;
2258
2259         if (name == NULL)
2260                 return NULL;
2261
2262         item = string_list_lookup(name, &fn_table);
2263         if (item != NULL)
2264                 return (struct patch *)item->util;
2265
2266         return NULL;
2267 }
2268
2269 static void add_to_fn_table(struct patch *patch)
2270 {
2271         struct string_list_item *item;
2272
2273         /*
2274          * Always add new_name unless patch is a deletion
2275          * This should cover the cases for normal diffs,
2276          * file creations and copies
2277          */
2278         if (patch->new_name != NULL) {
2279                 item = string_list_insert(patch->new_name, &fn_table);
2280                 item->util = patch;
2281         }
2282
2283         /*
2284          * store a failure on rename/deletion cases because
2285          * later chunks shouldn't patch old names
2286          */
2287         if ((patch->new_name == NULL) || (patch->is_rename)) {
2288                 item = string_list_insert(patch->old_name, &fn_table);
2289                 item->util = (struct patch *) -1;
2290         }
2291 }
2292
2293 static int apply_data(struct patch *patch, struct stat *st, struct cache_entry *ce)
2294 {
2295         struct strbuf buf;
2296         struct image image;
2297         size_t len;
2298         char *img;
2299         struct patch *tpatch;
2300
2301         strbuf_init(&buf, 0);
2302
2303         if (!(patch->is_copy || patch->is_rename) &&
2304             ((tpatch = in_fn_table(patch->old_name)) != NULL)) {
2305                 if (tpatch == (struct patch *) -1) {
2306                         return error("patch %s has been renamed/deleted",
2307                                 patch->old_name);
2308                 }
2309                 /* We have a patched copy in memory use that */
2310                 strbuf_add(&buf, tpatch->result, tpatch->resultsize);
2311         } else if (cached) {
2312                 if (read_file_or_gitlink(ce, &buf))
2313                         return error("read of %s failed", patch->old_name);
2314         } else if (patch->old_name) {
2315                 if (S_ISGITLINK(patch->old_mode)) {
2316                         if (ce) {
2317                                 read_file_or_gitlink(ce, &buf);
2318                         } else {
2319                                 /*
2320                                  * There is no way to apply subproject
2321                                  * patch without looking at the index.
2322                                  */
2323                                 patch->fragments = NULL;
2324                         }
2325                 } else {
2326                         if (read_old_data(st, patch->old_name, &buf))
2327                                 return error("read of %s failed", patch->old_name);
2328                 }
2329         }
2330
2331         img = strbuf_detach(&buf, &len);
2332         prepare_image(&image, img, len, !patch->is_binary);
2333
2334         if (apply_fragments(&image, patch) < 0)
2335                 return -1; /* note with --reject this succeeds. */
2336         patch->result = image.buf;
2337         patch->resultsize = image.len;
2338         add_to_fn_table(patch);
2339         free(image.line_allocated);
2340
2341         if (0 < patch->is_delete && patch->resultsize)
2342                 return error("removal patch leaves file contents");
2343
2344         return 0;
2345 }
2346
2347 static int check_to_create_blob(const char *new_name, int ok_if_exists)
2348 {
2349         struct stat nst;
2350         if (!lstat(new_name, &nst)) {
2351                 if (S_ISDIR(nst.st_mode) || ok_if_exists)
2352                         return 0;
2353                 /*
2354                  * A leading component of new_name might be a symlink
2355                  * that is going to be removed with this patch, but
2356                  * still pointing at somewhere that has the path.
2357                  * In such a case, path "new_name" does not exist as
2358                  * far as git is concerned.
2359                  */
2360                 if (has_symlink_leading_path(strlen(new_name), new_name))
2361                         return 0;
2362
2363                 return error("%s: already exists in working directory", new_name);
2364         }
2365         else if ((errno != ENOENT) && (errno != ENOTDIR))
2366                 return error("%s: %s", new_name, strerror(errno));
2367         return 0;
2368 }
2369
2370 static int verify_index_match(struct cache_entry *ce, struct stat *st)
2371 {
2372         if (S_ISGITLINK(ce->ce_mode)) {
2373                 if (!S_ISDIR(st->st_mode))
2374                         return -1;
2375                 return 0;
2376         }
2377         return ce_match_stat(ce, st, CE_MATCH_IGNORE_VALID);
2378 }
2379
2380 static int check_preimage(struct patch *patch, struct cache_entry **ce, struct stat *st)
2381 {
2382         const char *old_name = patch->old_name;
2383         struct patch *tpatch = NULL;
2384         int stat_ret = 0;
2385         unsigned st_mode = 0;
2386
2387         /*
2388          * Make sure that we do not have local modifications from the
2389          * index when we are looking at the index.  Also make sure
2390          * we have the preimage file to be patched in the work tree,
2391          * unless --cached, which tells git to apply only in the index.
2392          */
2393         if (!old_name)
2394                 return 0;
2395
2396         assert(patch->is_new <= 0);
2397
2398         if (!(patch->is_copy || patch->is_rename) &&
2399             (tpatch = in_fn_table(old_name)) != NULL) {
2400                 if (tpatch == (struct patch *) -1) {
2401                         return error("%s: has been deleted/renamed", old_name);
2402                 }
2403                 st_mode = tpatch->new_mode;
2404         } else if (!cached) {
2405                 stat_ret = lstat(old_name, st);
2406                 if (stat_ret && errno != ENOENT)
2407                         return error("%s: %s", old_name, strerror(errno));
2408         }
2409
2410         if (check_index && !tpatch) {
2411                 int pos = cache_name_pos(old_name, strlen(old_name));
2412                 if (pos < 0) {
2413                         if (patch->is_new < 0)
2414                                 goto is_new;
2415                         return error("%s: does not exist in index", old_name);
2416                 }
2417                 *ce = active_cache[pos];
2418                 if (stat_ret < 0) {
2419                         struct checkout costate;
2420                         /* checkout */
2421                         costate.base_dir = "";
2422                         costate.base_dir_len = 0;
2423                         costate.force = 0;
2424                         costate.quiet = 0;
2425                         costate.not_new = 0;
2426                         costate.refresh_cache = 1;
2427                         if (checkout_entry(*ce, &costate, NULL) ||
2428                             lstat(old_name, st))
2429                                 return -1;
2430                 }
2431                 if (!cached && verify_index_match(*ce, st))
2432                         return error("%s: does not match index", old_name);
2433                 if (cached)
2434                         st_mode = (*ce)->ce_mode;
2435         } else if (stat_ret < 0) {
2436                 if (patch->is_new < 0)
2437                         goto is_new;
2438                 return error("%s: %s", old_name, strerror(errno));
2439         }
2440
2441         if (!cached)
2442                 st_mode = ce_mode_from_stat(*ce, st->st_mode);
2443
2444         if (patch->is_new < 0)
2445                 patch->is_new = 0;
2446         if (!patch->old_mode)
2447                 patch->old_mode = st_mode;
2448         if ((st_mode ^ patch->old_mode) & S_IFMT)
2449                 return error("%s: wrong type", old_name);
2450         if (st_mode != patch->old_mode)
2451                 fprintf(stderr, "warning: %s has type %o, expected %o\n",
2452                         old_name, st_mode, patch->old_mode);
2453         return 0;
2454
2455  is_new:
2456         patch->is_new = 1;
2457         patch->is_delete = 0;
2458         patch->old_name = NULL;
2459         return 0;
2460 }
2461
2462 static int check_patch(struct patch *patch)
2463 {
2464         struct stat st;
2465         const char *old_name = patch->old_name;
2466         const char *new_name = patch->new_name;
2467         const char *name = old_name ? old_name : new_name;
2468         struct cache_entry *ce = NULL;
2469         int ok_if_exists;
2470         int status;
2471
2472         patch->rejected = 1; /* we will drop this after we succeed */
2473
2474         status = check_preimage(patch, &ce, &st);
2475         if (status)
2476                 return status;
2477         old_name = patch->old_name;
2478
2479         if (in_fn_table(new_name) == (struct patch *) -1)
2480                 /*
2481                  * A type-change diff is always split into a patch to
2482                  * delete old, immediately followed by a patch to
2483                  * create new (see diff.c::run_diff()); in such a case
2484                  * it is Ok that the entry to be deleted by the
2485                  * previous patch is still in the working tree and in
2486                  * the index.
2487                  */
2488                 ok_if_exists = 1;
2489         else
2490                 ok_if_exists = 0;
2491
2492         if (new_name &&
2493             ((0 < patch->is_new) | (0 < patch->is_rename) | patch->is_copy)) {
2494                 if (check_index &&
2495                     cache_name_pos(new_name, strlen(new_name)) >= 0 &&
2496                     !ok_if_exists)
2497                         return error("%s: already exists in index", new_name);
2498                 if (!cached) {
2499                         int err = check_to_create_blob(new_name, ok_if_exists);
2500                         if (err)
2501                                 return err;
2502                 }
2503                 if (!patch->new_mode) {
2504                         if (0 < patch->is_new)
2505                                 patch->new_mode = S_IFREG | 0644;
2506                         else
2507                                 patch->new_mode = patch->old_mode;
2508                 }
2509         }
2510
2511         if (new_name && old_name) {
2512                 int same = !strcmp(old_name, new_name);
2513                 if (!patch->new_mode)
2514                         patch->new_mode = patch->old_mode;
2515                 if ((patch->old_mode ^ patch->new_mode) & S_IFMT)
2516                         return error("new mode (%o) of %s does not match old mode (%o)%s%s",
2517                                 patch->new_mode, new_name, patch->old_mode,
2518                                 same ? "" : " of ", same ? "" : old_name);
2519         }
2520
2521         if (apply_data(patch, &st, ce) < 0)
2522                 return error("%s: patch does not apply", name);
2523         patch->rejected = 0;
2524         return 0;
2525 }
2526
2527 static int check_patch_list(struct patch *patch)
2528 {
2529         int err = 0;
2530
2531         while (patch) {
2532                 if (apply_verbosely)
2533                         say_patch_name(stderr,
2534                                        "Checking patch ", patch, "...\n");
2535                 err |= check_patch(patch);
2536                 patch = patch->next;
2537         }
2538         return err;
2539 }
2540
2541 /* This function tries to read the sha1 from the current index */
2542 static int get_current_sha1(const char *path, unsigned char *sha1)
2543 {
2544         int pos;
2545
2546         if (read_cache() < 0)
2547                 return -1;
2548         pos = cache_name_pos(path, strlen(path));
2549         if (pos < 0)
2550                 return -1;
2551         hashcpy(sha1, active_cache[pos]->sha1);
2552         return 0;
2553 }
2554
2555 /* Build an index that contains the just the files needed for a 3way merge */
2556 static void build_fake_ancestor(struct patch *list, const char *filename)
2557 {
2558         struct patch *patch;
2559         struct index_state result = { 0 };
2560         int fd;
2561
2562         /* Once we start supporting the reverse patch, it may be
2563          * worth showing the new sha1 prefix, but until then...
2564          */
2565         for (patch = list; patch; patch = patch->next) {
2566                 const unsigned char *sha1_ptr;
2567                 unsigned char sha1[20];
2568                 struct cache_entry *ce;
2569                 const char *name;
2570
2571                 name = patch->old_name ? patch->old_name : patch->new_name;
2572                 if (0 < patch->is_new)
2573                         continue;
2574                 else if (get_sha1(patch->old_sha1_prefix, sha1))
2575                         /* git diff has no index line for mode/type changes */
2576                         if (!patch->lines_added && !patch->lines_deleted) {
2577                                 if (get_current_sha1(patch->new_name, sha1) ||
2578                                     get_current_sha1(patch->old_name, sha1))
2579                                         die("mode change for %s, which is not "
2580                                                 "in current HEAD", name);
2581                                 sha1_ptr = sha1;
2582                         } else
2583                                 die("sha1 information is lacking or useless "
2584                                         "(%s).", name);
2585                 else
2586                         sha1_ptr = sha1;
2587
2588                 ce = make_cache_entry(patch->old_mode, sha1_ptr, name, 0, 0);
2589                 if (!ce)
2590                         die("make_cache_entry failed for path '%s'", name);
2591                 if (add_index_entry(&result, ce, ADD_CACHE_OK_TO_ADD))
2592                         die ("Could not add %s to temporary index", name);
2593         }
2594
2595         fd = open(filename, O_WRONLY | O_CREAT, 0666);
2596         if (fd < 0 || write_index(&result, fd) || close(fd))
2597                 die ("Could not write temporary index to %s", filename);
2598
2599         discard_index(&result);
2600 }
2601
2602 static void stat_patch_list(struct patch *patch)
2603 {
2604         int files, adds, dels;
2605
2606         for (files = adds = dels = 0 ; patch ; patch = patch->next) {
2607                 files++;
2608                 adds += patch->lines_added;
2609                 dels += patch->lines_deleted;
2610                 show_stats(patch);
2611         }
2612
2613         printf(" %d files changed, %d insertions(+), %d deletions(-)\n", files, adds, dels);
2614 }
2615
2616 static void numstat_patch_list(struct patch *patch)
2617 {
2618         for ( ; patch; patch = patch->next) {
2619                 const char *name;
2620                 name = patch->new_name ? patch->new_name : patch->old_name;
2621                 if (patch->is_binary)
2622                         printf("-\t-\t");
2623                 else
2624                         printf("%d\t%d\t", patch->lines_added, patch->lines_deleted);
2625                 write_name_quoted(name, stdout, line_termination);
2626         }
2627 }
2628
2629 static void show_file_mode_name(const char *newdelete, unsigned int mode, const char *name)
2630 {
2631         if (mode)
2632                 printf(" %s mode %06o %s\n", newdelete, mode, name);
2633         else
2634                 printf(" %s %s\n", newdelete, name);
2635 }
2636
2637 static void show_mode_change(struct patch *p, int show_name)
2638 {
2639         if (p->old_mode && p->new_mode && p->old_mode != p->new_mode) {
2640                 if (show_name)
2641                         printf(" mode change %06o => %06o %s\n",
2642                                p->old_mode, p->new_mode, p->new_name);
2643                 else
2644                         printf(" mode change %06o => %06o\n",
2645                                p->old_mode, p->new_mode);
2646         }
2647 }
2648
2649 static void show_rename_copy(struct patch *p)
2650 {
2651         const char *renamecopy = p->is_rename ? "rename" : "copy";
2652         const char *old, *new;
2653
2654         /* Find common prefix */
2655         old = p->old_name;
2656         new = p->new_name;
2657         while (1) {
2658                 const char *slash_old, *slash_new;
2659                 slash_old = strchr(old, '/');
2660                 slash_new = strchr(new, '/');
2661                 if (!slash_old ||
2662                     !slash_new ||
2663                     slash_old - old != slash_new - new ||
2664                     memcmp(old, new, slash_new - new))
2665                         break;
2666                 old = slash_old + 1;
2667                 new = slash_new + 1;
2668         }
2669         /* p->old_name thru old is the common prefix, and old and new
2670          * through the end of names are renames
2671          */
2672         if (old != p->old_name)
2673                 printf(" %s %.*s{%s => %s} (%d%%)\n", renamecopy,
2674                        (int)(old - p->old_name), p->old_name,
2675                        old, new, p->score);
2676         else
2677                 printf(" %s %s => %s (%d%%)\n", renamecopy,
2678                        p->old_name, p->new_name, p->score);
2679         show_mode_change(p, 0);
2680 }
2681
2682 static void summary_patch_list(struct patch *patch)
2683 {
2684         struct patch *p;
2685
2686         for (p = patch; p; p = p->next) {
2687                 if (p->is_new)
2688                         show_file_mode_name("create", p->new_mode, p->new_name);
2689                 else if (p->is_delete)
2690                         show_file_mode_name("delete", p->old_mode, p->old_name);
2691                 else {
2692                         if (p->is_rename || p->is_copy)
2693                                 show_rename_copy(p);
2694                         else {
2695                                 if (p->score) {
2696                                         printf(" rewrite %s (%d%%)\n",
2697                                                p->new_name, p->score);
2698                                         show_mode_change(p, 0);
2699                                 }
2700                                 else
2701                                         show_mode_change(p, 1);
2702                         }
2703                 }
2704         }
2705 }
2706
2707 static void patch_stats(struct patch *patch)
2708 {
2709         int lines = patch->lines_added + patch->lines_deleted;
2710
2711         if (lines > max_change)
2712                 max_change = lines;
2713         if (patch->old_name) {
2714                 int len = quote_c_style(patch->old_name, NULL, NULL, 0);
2715                 if (!len)
2716                         len = strlen(patch->old_name);
2717                 if (len > max_len)
2718                         max_len = len;
2719         }
2720         if (patch->new_name) {
2721                 int len = quote_c_style(patch->new_name, NULL, NULL, 0);
2722                 if (!len)
2723                         len = strlen(patch->new_name);
2724                 if (len > max_len)
2725                         max_len = len;
2726         }
2727 }
2728
2729 static void remove_file(struct patch *patch, int rmdir_empty)
2730 {
2731         if (update_index) {
2732                 if (remove_file_from_cache(patch->old_name) < 0)
2733                         die("unable to remove %s from index", patch->old_name);
2734         }
2735         if (!cached) {
2736                 if (S_ISGITLINK(patch->old_mode)) {
2737                         if (rmdir(patch->old_name))
2738                                 warning("unable to remove submodule %s",
2739                                         patch->old_name);
2740                 } else if (!unlink(patch->old_name) && rmdir_empty) {
2741                         remove_path(patch->old_name);
2742                 }
2743         }
2744 }
2745
2746 static void add_index_file(const char *path, unsigned mode, void *buf, unsigned long size)
2747 {
2748         struct stat st;
2749         struct cache_entry *ce;
2750         int namelen = strlen(path);
2751         unsigned ce_size = cache_entry_size(namelen);
2752
2753         if (!update_index)
2754                 return;
2755
2756         ce = xcalloc(1, ce_size);
2757         memcpy(ce->name, path, namelen);
2758         ce->ce_mode = create_ce_mode(mode);
2759         ce->ce_flags = namelen;
2760         if (S_ISGITLINK(mode)) {
2761                 const char *s = buf;
2762
2763                 if (get_sha1_hex(s + strlen("Subproject commit "), ce->sha1))
2764                         die("corrupt patch for subproject %s", path);
2765         } else {
2766                 if (!cached) {
2767                         if (lstat(path, &st) < 0)
2768                                 die("unable to stat newly created file %s",
2769                                     path);
2770                         fill_stat_cache_info(ce, &st);
2771                 }
2772                 if (write_sha1_file(buf, size, blob_type, ce->sha1) < 0)
2773                         die("unable to create backing store for newly created file %s", path);
2774         }
2775         if (add_cache_entry(ce, ADD_CACHE_OK_TO_ADD) < 0)
2776                 die("unable to add cache entry for %s", path);
2777 }
2778
2779 static int try_create_file(const char *path, unsigned int mode, const char *buf, unsigned long size)
2780 {
2781         int fd;
2782         struct strbuf nbuf;
2783
2784         if (S_ISGITLINK(mode)) {
2785                 struct stat st;
2786                 if (!lstat(path, &st) && S_ISDIR(st.st_mode))
2787                         return 0;
2788                 return mkdir(path, 0777);
2789         }
2790
2791         if (has_symlinks && S_ISLNK(mode))
2792                 /* Although buf:size is counted string, it also is NUL
2793                  * terminated.
2794                  */
2795                 return symlink(buf, path);
2796
2797         fd = open(path, O_CREAT | O_EXCL | O_WRONLY, (mode & 0100) ? 0777 : 0666);
2798         if (fd < 0)
2799                 return -1;
2800
2801         strbuf_init(&nbuf, 0);
2802         if (convert_to_working_tree(path, buf, size, &nbuf)) {
2803                 size = nbuf.len;
2804                 buf  = nbuf.buf;
2805         }
2806         write_or_die(fd, buf, size);
2807         strbuf_release(&nbuf);
2808
2809         if (close(fd) < 0)
2810                 die("closing file %s: %s", path, strerror(errno));
2811         return 0;
2812 }
2813
2814 /*
2815  * We optimistically assume that the directories exist,
2816  * which is true 99% of the time anyway. If they don't,
2817  * we create them and try again.
2818  */
2819 static void create_one_file(char *path, unsigned mode, const char *buf, unsigned long size)
2820 {
2821         if (cached)
2822                 return;
2823         if (!try_create_file(path, mode, buf, size))
2824                 return;
2825
2826         if (errno == ENOENT) {
2827                 if (safe_create_leading_directories(path))
2828                         return;
2829                 if (!try_create_file(path, mode, buf, size))
2830                         return;
2831         }
2832
2833         if (errno == EEXIST || errno == EACCES) {
2834                 /* We may be trying to create a file where a directory
2835                  * used to be.
2836                  */
2837                 struct stat st;
2838                 if (!lstat(path, &st) && (!S_ISDIR(st.st_mode) || !rmdir(path)))
2839                         errno = EEXIST;
2840         }
2841
2842         if (errno == EEXIST) {
2843                 unsigned int nr = getpid();
2844
2845                 for (;;) {
2846                         const char *newpath;
2847                         newpath = mkpath("%s~%u", path, nr);
2848                         if (!try_create_file(newpath, mode, buf, size)) {
2849                                 if (!rename(newpath, path))
2850                                         return;
2851                                 unlink(newpath);
2852                                 break;
2853                         }
2854                         if (errno != EEXIST)
2855                                 break;
2856                         ++nr;
2857                 }
2858         }
2859         die("unable to write file %s mode %o", path, mode);
2860 }
2861
2862 static void create_file(struct patch *patch)
2863 {
2864         char *path = patch->new_name;
2865         unsigned mode = patch->new_mode;
2866         unsigned long size = patch->resultsize;
2867         char *buf = patch->result;
2868
2869         if (!mode)
2870                 mode = S_IFREG | 0644;
2871         create_one_file(path, mode, buf, size);
2872         add_index_file(path, mode, buf, size);
2873 }
2874
2875 /* phase zero is to remove, phase one is to create */
2876 static void write_out_one_result(struct patch *patch, int phase)
2877 {
2878         if (patch->is_delete > 0) {
2879                 if (phase == 0)
2880                         remove_file(patch, 1);
2881                 return;
2882         }
2883         if (patch->is_new > 0 || patch->is_copy) {
2884                 if (phase == 1)
2885                         create_file(patch);
2886                 return;
2887         }
2888         /*
2889          * Rename or modification boils down to the same
2890          * thing: remove the old, write the new
2891          */
2892         if (phase == 0)
2893                 remove_file(patch, patch->is_rename);
2894         if (phase == 1)
2895                 create_file(patch);
2896 }
2897
2898 static int write_out_one_reject(struct patch *patch)
2899 {
2900         FILE *rej;
2901         char namebuf[PATH_MAX];
2902         struct fragment *frag;
2903         int cnt = 0;
2904
2905         for (cnt = 0, frag = patch->fragments; frag; frag = frag->next) {
2906                 if (!frag->rejected)
2907                         continue;
2908                 cnt++;
2909         }
2910
2911         if (!cnt) {
2912                 if (apply_verbosely)
2913                         say_patch_name(stderr,
2914                                        "Applied patch ", patch, " cleanly.\n");
2915                 return 0;
2916         }
2917
2918         /* This should not happen, because a removal patch that leaves
2919          * contents are marked "rejected" at the patch level.
2920          */
2921         if (!patch->new_name)
2922                 die("internal error");
2923
2924         /* Say this even without --verbose */
2925         say_patch_name(stderr, "Applying patch ", patch, " with");
2926         fprintf(stderr, " %d rejects...\n", cnt);
2927
2928         cnt = strlen(patch->new_name);
2929         if (ARRAY_SIZE(namebuf) <= cnt + 5) {
2930                 cnt = ARRAY_SIZE(namebuf) - 5;
2931                 fprintf(stderr,
2932                         "warning: truncating .rej filename to %.*s.rej",
2933                         cnt - 1, patch->new_name);
2934         }
2935         memcpy(namebuf, patch->new_name, cnt);
2936         memcpy(namebuf + cnt, ".rej", 5);
2937
2938         rej = fopen(namebuf, "w");
2939         if (!rej)
2940                 return error("cannot open %s: %s", namebuf, strerror(errno));
2941
2942         /* Normal git tools never deal with .rej, so do not pretend
2943          * this is a git patch by saying --git nor give extended
2944          * headers.  While at it, maybe please "kompare" that wants
2945          * the trailing TAB and some garbage at the end of line ;-).
2946          */
2947         fprintf(rej, "diff a/%s b/%s\t(rejected hunks)\n",
2948                 patch->new_name, patch->new_name);
2949         for (cnt = 1, frag = patch->fragments;
2950              frag;
2951              cnt++, frag = frag->next) {
2952                 if (!frag->rejected) {
2953                         fprintf(stderr, "Hunk #%d applied cleanly.\n", cnt);
2954                         continue;
2955                 }
2956                 fprintf(stderr, "Rejected hunk #%d.\n", cnt);
2957                 fprintf(rej, "%.*s", frag->size, frag->patch);
2958                 if (frag->patch[frag->size-1] != '\n')
2959                         fputc('\n', rej);
2960         }
2961         fclose(rej);
2962         return -1;
2963 }
2964
2965 static int write_out_results(struct patch *list, int skipped_patch)
2966 {
2967         int phase;
2968         int errs = 0;
2969         struct patch *l;
2970
2971         if (!list && !skipped_patch)
2972                 return error("No changes");
2973
2974         for (phase = 0; phase < 2; phase++) {
2975                 l = list;
2976                 while (l) {
2977                         if (l->rejected)
2978                                 errs = 1;
2979                         else {
2980                                 write_out_one_result(l, phase);
2981                                 if (phase == 1 && write_out_one_reject(l))
2982                                         errs = 1;
2983                         }
2984                         l = l->next;
2985                 }
2986         }
2987         return errs;
2988 }
2989
2990 static struct lock_file lock_file;
2991
2992 static struct string_list limit_by_name;
2993 static int has_include;
2994 static void add_name_limit(const char *name, int exclude)
2995 {
2996         struct string_list_item *it;
2997
2998         it = string_list_append(name, &limit_by_name);
2999         it->util = exclude ? NULL : (void *) 1;
3000 }
3001
3002 static int use_patch(struct patch *p)
3003 {
3004         const char *pathname = p->new_name ? p->new_name : p->old_name;
3005         int i;
3006
3007         /* Paths outside are not touched regardless of "--include" */
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
3015         /* See if it matches any of exclude/include rule */
3016         for (i = 0; i < limit_by_name.nr; i++) {
3017                 struct string_list_item *it = &limit_by_name.items[i];
3018                 if (!fnmatch(it->string, pathname, 0))
3019                         return (it->util != NULL);
3020         }
3021
3022         /*
3023          * If we had any include, a path that does not match any rule is
3024          * not used.  Otherwise, we saw bunch of exclude rules (or none)
3025          * and such a path is used.
3026          */
3027         return !has_include;
3028 }
3029
3030
3031 static void prefix_one(char **name)
3032 {
3033         char *old_name = *name;
3034         if (!old_name)
3035                 return;
3036         *name = xstrdup(prefix_filename(prefix, prefix_length, *name));
3037         free(old_name);
3038 }
3039
3040 static void prefix_patches(struct patch *p)
3041 {
3042         if (!prefix || p->is_toplevel_relative)
3043                 return;
3044         for ( ; p; p = p->next) {
3045                 if (p->new_name == p->old_name) {
3046                         char *prefixed = p->new_name;
3047                         prefix_one(&prefixed);
3048                         p->new_name = p->old_name = prefixed;
3049                 }
3050                 else {
3051                         prefix_one(&p->new_name);
3052                         prefix_one(&p->old_name);
3053                 }
3054         }
3055 }
3056
3057 #define INACCURATE_EOF  (1<<0)
3058 #define RECOUNT         (1<<1)
3059
3060 static int apply_patch(int fd, const char *filename, int options)
3061 {
3062         size_t offset;
3063         struct strbuf buf;
3064         struct patch *list = NULL, **listp = &list;
3065         int skipped_patch = 0;
3066
3067         /* FIXME - memory leak when using multiple patch files as inputs */
3068         memset(&fn_table, 0, sizeof(struct string_list));
3069         strbuf_init(&buf, 0);
3070         patch_input_file = filename;
3071         read_patch_file(&buf, fd);
3072         offset = 0;
3073         while (offset < buf.len) {
3074                 struct patch *patch;
3075                 int nr;
3076
3077                 patch = xcalloc(1, sizeof(*patch));
3078                 patch->inaccurate_eof = !!(options & INACCURATE_EOF);
3079                 patch->recount =  !!(options & RECOUNT);
3080                 nr = parse_chunk(buf.buf + offset, buf.len - offset, patch);
3081                 if (nr < 0)
3082                         break;
3083                 if (apply_in_reverse)
3084                         reverse_patches(patch);
3085                 if (prefix)
3086                         prefix_patches(patch);
3087                 if (use_patch(patch)) {
3088                         patch_stats(patch);
3089                         *listp = patch;
3090                         listp = &patch->next;
3091                 }
3092                 else {
3093                         /* perhaps free it a bit better? */
3094                         free(patch);
3095                         skipped_patch++;
3096                 }
3097                 offset += nr;
3098         }
3099
3100         if (whitespace_error && (ws_error_action == die_on_ws_error))
3101                 apply = 0;
3102
3103         update_index = check_index && apply;
3104         if (update_index && newfd < 0)
3105                 newfd = hold_locked_index(&lock_file, 1);
3106
3107         if (check_index) {
3108                 if (read_cache() < 0)
3109                         die("unable to read index file");
3110         }
3111
3112         if ((check || apply) &&
3113             check_patch_list(list) < 0 &&
3114             !apply_with_reject)
3115                 exit(1);
3116
3117         if (apply && write_out_results(list, skipped_patch))
3118                 exit(1);
3119
3120         if (fake_ancestor)
3121                 build_fake_ancestor(list, fake_ancestor);
3122
3123         if (diffstat)
3124                 stat_patch_list(list);
3125
3126         if (numstat)
3127                 numstat_patch_list(list);
3128
3129         if (summary)
3130                 summary_patch_list(list);
3131
3132         strbuf_release(&buf);
3133         return 0;
3134 }
3135
3136 static int git_apply_config(const char *var, const char *value, void *cb)
3137 {
3138         if (!strcmp(var, "apply.whitespace"))
3139                 return git_config_string(&apply_default_whitespace, var, value);
3140         return git_default_config(var, value, cb);
3141 }
3142
3143
3144 int cmd_apply(int argc, const char **argv, const char *unused_prefix)
3145 {
3146         int i;
3147         int read_stdin = 1;
3148         int options = 0;
3149         int errs = 0;
3150         int is_not_gitdir;
3151
3152         const char *whitespace_option = NULL;
3153
3154         prefix = setup_git_directory_gently(&is_not_gitdir);
3155         prefix_length = prefix ? strlen(prefix) : 0;
3156         git_config(git_apply_config, NULL);
3157         if (apply_default_whitespace)
3158                 parse_whitespace_option(apply_default_whitespace);
3159
3160         for (i = 1; i < argc; i++) {
3161                 const char *arg = argv[i];
3162                 char *end;
3163                 int fd;
3164
3165                 if (!strcmp(arg, "-")) {
3166                         errs |= apply_patch(0, "<stdin>", options);
3167                         read_stdin = 0;
3168                         continue;
3169                 }
3170                 if (!prefixcmp(arg, "--exclude=")) {
3171                         add_name_limit(arg + 10, 1);
3172                         continue;
3173                 }
3174                 if (!prefixcmp(arg, "--include=")) {
3175                         add_name_limit(arg + 10, 0);
3176                         has_include = 1;
3177                         continue;
3178                 }
3179                 if (!prefixcmp(arg, "-p")) {
3180                         p_value = atoi(arg + 2);
3181                         p_value_known = 1;
3182                         continue;
3183                 }
3184                 if (!strcmp(arg, "--no-add")) {
3185                         no_add = 1;
3186                         continue;
3187                 }
3188                 if (!strcmp(arg, "--stat")) {
3189                         apply = 0;
3190                         diffstat = 1;
3191                         continue;
3192                 }
3193                 if (!strcmp(arg, "--allow-binary-replacement") ||
3194                     !strcmp(arg, "--binary")) {
3195                         continue; /* now no-op */
3196                 }
3197                 if (!strcmp(arg, "--numstat")) {
3198                         apply = 0;
3199                         numstat = 1;
3200                         continue;
3201                 }
3202                 if (!strcmp(arg, "--summary")) {
3203                         apply = 0;
3204                         summary = 1;
3205                         continue;
3206                 }
3207                 if (!strcmp(arg, "--check")) {
3208                         apply = 0;
3209                         check = 1;
3210                         continue;
3211                 }
3212                 if (!strcmp(arg, "--index")) {
3213                         if (is_not_gitdir)
3214                                 die("--index outside a repository");
3215                         check_index = 1;
3216                         continue;
3217                 }
3218                 if (!strcmp(arg, "--cached")) {
3219                         if (is_not_gitdir)
3220                                 die("--cached outside a repository");
3221                         check_index = 1;
3222                         cached = 1;
3223                         continue;
3224                 }
3225                 if (!strcmp(arg, "--apply")) {
3226                         apply = 1;
3227                         continue;
3228                 }
3229                 if (!strcmp(arg, "--build-fake-ancestor")) {
3230                         apply = 0;
3231                         if (++i >= argc)
3232                                 die ("need a filename");
3233                         fake_ancestor = argv[i];
3234                         continue;
3235                 }
3236                 if (!strcmp(arg, "-z")) {
3237                         line_termination = 0;
3238                         continue;
3239                 }
3240                 if (!prefixcmp(arg, "-C")) {
3241                         p_context = strtoul(arg + 2, &end, 0);
3242                         if (*end != '\0')
3243                                 die("unrecognized context count '%s'", arg + 2);
3244                         continue;
3245                 }
3246                 if (!prefixcmp(arg, "--whitespace=")) {
3247                         whitespace_option = arg + 13;
3248                         parse_whitespace_option(arg + 13);
3249                         continue;
3250                 }
3251                 if (!strcmp(arg, "-R") || !strcmp(arg, "--reverse")) {
3252                         apply_in_reverse = 1;
3253                         continue;
3254                 }
3255                 if (!strcmp(arg, "--unidiff-zero")) {
3256                         unidiff_zero = 1;
3257                         continue;
3258                 }
3259                 if (!strcmp(arg, "--reject")) {
3260                         apply = apply_with_reject = apply_verbosely = 1;
3261                         continue;
3262                 }
3263                 if (!strcmp(arg, "-v") || !strcmp(arg, "--verbose")) {
3264                         apply_verbosely = 1;
3265                         continue;
3266                 }
3267                 if (!strcmp(arg, "--inaccurate-eof")) {
3268                         options |= INACCURATE_EOF;
3269                         continue;
3270                 }
3271                 if (!strcmp(arg, "--recount")) {
3272                         options |= RECOUNT;
3273                         continue;
3274                 }
3275                 if (!prefixcmp(arg, "--directory=")) {
3276                         arg += strlen("--directory=");
3277                         root_len = strlen(arg);
3278                         if (root_len && arg[root_len - 1] != '/') {
3279                                 char *new_root;
3280                                 root = new_root = xmalloc(root_len + 2);
3281                                 strcpy(new_root, arg);
3282                                 strcpy(new_root + root_len++, "/");
3283                         } else
3284                                 root = arg;
3285                         continue;
3286                 }
3287                 if (0 < prefix_length)
3288                         arg = prefix_filename(prefix, prefix_length, arg);
3289
3290                 fd = open(arg, O_RDONLY);
3291                 if (fd < 0)
3292                         die("can't open patch '%s': %s", arg, strerror(errno));
3293                 read_stdin = 0;
3294                 set_default_whitespace_mode(whitespace_option);
3295                 errs |= apply_patch(fd, arg, options);
3296                 close(fd);
3297         }
3298         set_default_whitespace_mode(whitespace_option);
3299         if (read_stdin)
3300                 errs |= apply_patch(0, "<stdin>", options);
3301         if (whitespace_error) {
3302                 if (squelch_whitespace_errors &&
3303                     squelch_whitespace_errors < whitespace_error) {
3304                         int squelched =
3305                                 whitespace_error - squelch_whitespace_errors;
3306                         fprintf(stderr, "warning: squelched %d "
3307                                 "whitespace error%s\n",
3308                                 squelched,
3309                                 squelched == 1 ? "" : "s");
3310                 }
3311                 if (ws_error_action == die_on_ws_error)
3312                         die("%d line%s add%s whitespace errors.",
3313                             whitespace_error,
3314                             whitespace_error == 1 ? "" : "s",
3315                             whitespace_error == 1 ? "s" : "");
3316                 if (applied_after_fixing_ws && apply)
3317                         fprintf(stderr, "warning: %d line%s applied after"
3318                                 " fixing whitespace errors.\n",
3319                                 applied_after_fixing_ws,
3320                                 applied_after_fixing_ws == 1 ? "" : "s");
3321                 else if (whitespace_error)
3322                         fprintf(stderr, "warning: %d line%s add%s whitespace errors.\n",
3323                                 whitespace_error,
3324                                 whitespace_error == 1 ? "" : "s",
3325                                 whitespace_error == 1 ? "s" : "");
3326         }
3327
3328         if (update_index) {
3329                 if (write_cache(newfd, active_cache, active_nr) ||
3330                     commit_locked_index(&lock_file))
3331                         die("Unable to write new index file");
3332         }
3333
3334         return !!errs;
3335 }