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[git/git.git] / apply.c
CommitLineData
c1bb9350
LT
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 * NOTE! It does all its work in the index file, and only cares about
9 * the files in the working directory if you tell it to "merge" the
10 * patch apply.
11 *
12 * Even when merging it always takes the source from the index, and
13 * uses the working tree as a "branch" for a 3-way merge.
14 */
15#include <ctype.h>
16
17#include "cache.h"
18
19// We default to the merge behaviour, since that's what most people would
a577284a
LT
20// expect.
21//
22// --check turns on checking that the working tree matches the
23// files that are being modified, but doesn't apply the patch
24// --stat does just a diffstat, and doesn't actually apply
25// --show-files shows the directory changes
26//
c1bb9350 27static int merge_patch = 1;
3cca928d 28static int check_index = 0;
5aa7d94c 29static int write_index = 0;
fab2c257 30static int diffstat = 0;
a577284a
LT
31static int check = 0;
32static int apply = 1;
33static int show_files = 0;
34static const char apply_usage[] = "git-apply [--stat] [--check] [--show-files] <patch>";
c1bb9350 35
3f40315a
LT
36/*
37 * For "diff-stat" like behaviour, we keep track of the biggest change
38 * we've seen, and the longest filename. That allows us to do simple
39 * scaling.
40 */
41static int max_change, max_len;
42
a4acb0eb
LT
43/*
44 * Various "current state", notably line numbers and what
45 * file (and how) we're patching right now.. The "is_xxxx"
46 * things are flags, where -1 means "don't know yet".
47 */
46979f56 48static int linenr = 1;
19c58fb8
LT
49
50struct fragment {
51 unsigned long oldpos, oldlines;
52 unsigned long newpos, newlines;
53 const char *patch;
54 int size;
55 struct fragment *next;
56};
57
58struct patch {
5041aa70 59 char *new_name, *old_name, *def_name;
19c58fb8
LT
60 unsigned int old_mode, new_mode;
61 int is_rename, is_copy, is_new, is_delete;
3f40315a 62 int lines_added, lines_deleted;
19c58fb8 63 struct fragment *fragments;
5aa7d94c 64 char *result;
3cca928d 65 unsigned long resultsize;
19c58fb8
LT
66 struct patch *next;
67};
46979f56 68
c1bb9350 69#define CHUNKSIZE (8192)
a4acb0eb 70#define SLOP (16)
c1bb9350
LT
71
72static void *read_patch_file(int fd, unsigned long *sizep)
73{
74 unsigned long size = 0, alloc = CHUNKSIZE;
75 void *buffer = xmalloc(alloc);
76
77 for (;;) {
78 int nr = alloc - size;
79 if (nr < 1024) {
80 alloc += CHUNKSIZE;
81 buffer = xrealloc(buffer, alloc);
82 nr = alloc - size;
83 }
84 nr = read(fd, buffer + size, nr);
85 if (!nr)
86 break;
87 if (nr < 0) {
88 if (errno == EAGAIN)
89 continue;
90 die("git-apply: read returned %s", strerror(errno));
91 }
92 size += nr;
93 }
94 *sizep = size;
a4acb0eb
LT
95
96 /*
97 * Make sure that we have some slop in the buffer
98 * so that we can do speculative "memcmp" etc, and
99 * see to it that it is NUL-filled.
100 */
101 if (alloc < size + SLOP)
102 buffer = xrealloc(buffer, size + SLOP);
103 memset(buffer + size, 0, SLOP);
c1bb9350
LT
104 return buffer;
105}
106
3cca928d 107static unsigned long linelen(const char *buffer, unsigned long size)
c1bb9350
LT
108{
109 unsigned long len = 0;
110 while (size--) {
111 len++;
112 if (*buffer++ == '\n')
113 break;
114 }
115 return len;
116}
117
a4acb0eb
LT
118static int is_dev_null(const char *str)
119{
120 return !memcmp("/dev/null", str, 9) && isspace(str[9]);
121}
122
381ca9a3
LT
123#define TERM_SPACE 1
124#define TERM_TAB 2
9a4a100e
LT
125
126static int name_terminate(const char *name, int namelen, int c, int terminate)
127{
128 if (c == ' ' && !(terminate & TERM_SPACE))
129 return 0;
130 if (c == '\t' && !(terminate & TERM_TAB))
131 return 0;
132
9a4a100e
LT
133 return 1;
134}
135
136static char * find_name(const char *line, char *def, int p_value, int terminate)
c1bb9350 137{
a4acb0eb
LT
138 int len;
139 const char *start = line;
140 char *name;
141
c1bb9350 142 for (;;) {
a4acb0eb 143 char c = *line;
9a4a100e
LT
144
145 if (isspace(c)) {
146 if (c == '\n')
147 break;
148 if (name_terminate(start, line-start, c, terminate))
149 break;
150 }
a4acb0eb
LT
151 line++;
152 if (c == '/' && !--p_value)
153 start = line;
154 }
155 if (!start)
156 return def;
157 len = line - start;
158 if (!len)
159 return def;
160
161 /*
162 * Generally we prefer the shorter name, especially
163 * if the other one is just a variation of that with
164 * something else tacked on to the end (ie "file.orig"
165 * or "file~").
166 */
167 if (def) {
168 int deflen = strlen(def);
169 if (deflen < len && !strncmp(start, def, deflen))
170 return def;
c1bb9350 171 }
a4acb0eb
LT
172
173 name = xmalloc(len + 1);
174 memcpy(name, start, len);
175 name[len] = 0;
176 free(def);
177 return name;
178}
179
180/*
181 * Get the name etc info from the --/+++ lines of a traditional patch header
182 *
183 * NOTE! This hardcodes "-p1" behaviour in filename detection.
9a4a100e
LT
184 *
185 * FIXME! The end-of-filename heuristics are kind of screwy. For existing
186 * files, we can happily check the index for a match, but for creating a
187 * new file we should try to match whatever "patch" does. I have no idea.
a4acb0eb 188 */
19c58fb8 189static void parse_traditional_patch(const char *first, const char *second, struct patch *patch)
a4acb0eb
LT
190{
191 int p_value = 1;
192 char *name;
193
194 first += 4; // skip "--- "
195 second += 4; // skip "+++ "
196 if (is_dev_null(first)) {
19c58fb8
LT
197 patch->is_new = 1;
198 patch->is_delete = 0;
5041aa70 199 name = find_name(second, NULL, p_value, TERM_SPACE | TERM_TAB);
19c58fb8 200 patch->new_name = name;
a4acb0eb 201 } else if (is_dev_null(second)) {
19c58fb8
LT
202 patch->is_new = 0;
203 patch->is_delete = 1;
381ca9a3 204 name = find_name(first, NULL, p_value, TERM_SPACE | TERM_TAB);
19c58fb8 205 patch->old_name = name;
a4acb0eb 206 } else {
381ca9a3
LT
207 name = find_name(first, NULL, p_value, TERM_SPACE | TERM_TAB);
208 name = find_name(second, name, p_value, TERM_SPACE | TERM_TAB);
19c58fb8 209 patch->old_name = patch->new_name = name;
a4acb0eb
LT
210 }
211 if (!name)
212 die("unable to find filename in patch at line %d", linenr);
a4acb0eb
LT
213}
214
19c58fb8 215static int gitdiff_hdrend(const char *line, struct patch *patch)
a4acb0eb
LT
216{
217 return -1;
218}
219
1e3f6b6e
LT
220/*
221 * We're anal about diff header consistency, to make
222 * sure that we don't end up having strange ambiguous
223 * patches floating around.
224 *
225 * As a result, gitdiff_{old|new}name() will check
226 * their names against any previous information, just
227 * to make sure..
228 */
229static char *gitdiff_verify_name(const char *line, int isnull, char *orig_name, const char *oldnew)
230{
231 int len;
232 const char *name;
233
234 if (!orig_name && !isnull)
235 return find_name(line, NULL, 1, 0);
236
237 name = "/dev/null";
238 len = 9;
239 if (orig_name) {
240 name = orig_name;
241 len = strlen(name);
242 if (isnull)
243 die("git-apply: bad git-diff - expected /dev/null, got %s on line %d", name, linenr);
244 }
245
246 if (*name == '/')
247 goto absolute_path;
248
249 for (;;) {
250 char c = *line++;
251 if (c == '\n')
252 break;
253 if (c != '/')
254 continue;
255absolute_path:
256 if (memcmp(line, name, len) || line[len] != '\n')
257 break;
258 return orig_name;
259 }
260 die("git-apply: bad git-diff - inconsistent %s filename on line %d", oldnew, linenr);
261 return NULL;
262}
263
19c58fb8 264static int gitdiff_oldname(const char *line, struct patch *patch)
a4acb0eb 265{
19c58fb8 266 patch->old_name = gitdiff_verify_name(line, patch->is_new, patch->old_name, "old");
a4acb0eb
LT
267 return 0;
268}
269
19c58fb8 270static int gitdiff_newname(const char *line, struct patch *patch)
a4acb0eb 271{
19c58fb8 272 patch->new_name = gitdiff_verify_name(line, patch->is_delete, patch->new_name, "new");
a4acb0eb
LT
273 return 0;
274}
275
19c58fb8 276static int gitdiff_oldmode(const char *line, struct patch *patch)
a4acb0eb 277{
19c58fb8 278 patch->old_mode = strtoul(line, NULL, 8);
a4acb0eb
LT
279 return 0;
280}
281
19c58fb8 282static int gitdiff_newmode(const char *line, struct patch *patch)
a4acb0eb 283{
19c58fb8 284 patch->new_mode = strtoul(line, NULL, 8);
a4acb0eb
LT
285 return 0;
286}
287
19c58fb8 288static int gitdiff_delete(const char *line, struct patch *patch)
a4acb0eb 289{
19c58fb8 290 patch->is_delete = 1;
5041aa70 291 patch->old_name = patch->def_name;
19c58fb8 292 return gitdiff_oldmode(line, patch);
a4acb0eb
LT
293}
294
19c58fb8 295static int gitdiff_newfile(const char *line, struct patch *patch)
a4acb0eb 296{
19c58fb8 297 patch->is_new = 1;
5041aa70 298 patch->new_name = patch->def_name;
19c58fb8 299 return gitdiff_newmode(line, patch);
a4acb0eb
LT
300}
301
19c58fb8 302static int gitdiff_copysrc(const char *line, struct patch *patch)
a4acb0eb 303{
19c58fb8
LT
304 patch->is_copy = 1;
305 patch->old_name = find_name(line, NULL, 0, 0);
a4acb0eb
LT
306 return 0;
307}
308
19c58fb8 309static int gitdiff_copydst(const char *line, struct patch *patch)
a4acb0eb 310{
19c58fb8
LT
311 patch->is_copy = 1;
312 patch->new_name = find_name(line, NULL, 0, 0);
a4acb0eb
LT
313 return 0;
314}
315
19c58fb8 316static int gitdiff_renamesrc(const char *line, struct patch *patch)
a4acb0eb 317{
19c58fb8
LT
318 patch->is_rename = 1;
319 patch->old_name = find_name(line, NULL, 0, 0);
a4acb0eb
LT
320 return 0;
321}
322
19c58fb8 323static int gitdiff_renamedst(const char *line, struct patch *patch)
a4acb0eb 324{
19c58fb8
LT
325 patch->is_rename = 1;
326 patch->new_name = find_name(line, NULL, 0, 0);
a4acb0eb
LT
327 return 0;
328}
329
19c58fb8 330static int gitdiff_similarity(const char *line, struct patch *patch)
a4acb0eb
LT
331{
332 return 0;
c1bb9350
LT
333}
334
70aadac0
JH
335static int gitdiff_dissimilarity(const char *line, struct patch *patch)
336{
337 return 0;
338}
339
9a4a100e
LT
340/*
341 * This is normal for a diff that doesn't change anything: we'll fall through
342 * into the next diff. Tell the parser to break out.
343 */
19c58fb8 344static int gitdiff_unrecognized(const char *line, struct patch *patch)
9a4a100e
LT
345{
346 return -1;
347}
348
5041aa70
LT
349static char *git_header_name(char *line)
350{
351 int len;
352 char *name, *second;
353
354 /*
355 * Find the first '/'
356 */
357 name = line;
358 for (;;) {
359 char c = *name++;
360 if (c == '\n')
361 return NULL;
362 if (c == '/')
363 break;
364 }
365
366 /*
367 * We don't accept absolute paths (/dev/null) as possibly valid
368 */
369 if (name == line+1)
370 return NULL;
371
372 /*
373 * Accept a name only if it shows up twice, exactly the same
374 * form.
375 */
376 for (len = 0 ; ; len++) {
377 char c = name[len];
378
379 switch (c) {
380 default:
381 continue;
382 case '\n':
383 break;
384 case '\t': case ' ':
385 second = name+len;
386 for (;;) {
387 char c = *second++;
388 if (c == '\n')
389 return NULL;
390 if (c == '/')
391 break;
392 }
0e87e048 393 if (second[len] == '\n' && !memcmp(name, second, len)) {
5041aa70
LT
394 char *ret = xmalloc(len + 1);
395 memcpy(ret, name, len);
396 ret[len] = 0;
397 return ret;
398 }
399 }
400 }
401 return NULL;
402}
403
c1bb9350 404/* Verify that we recognize the lines following a git header */
19c58fb8 405static int parse_git_header(char *line, int len, unsigned int size, struct patch *patch)
c1bb9350 406{
a4acb0eb
LT
407 unsigned long offset;
408
409 /* A git diff has explicit new/delete information, so we don't guess */
19c58fb8
LT
410 patch->is_new = 0;
411 patch->is_delete = 0;
a4acb0eb 412
5041aa70
LT
413 /*
414 * Some things may not have the old name in the
415 * rest of the headers anywhere (pure mode changes,
416 * or removing or adding empty files), so we get
417 * the default name from the header.
418 */
419 patch->def_name = git_header_name(line + strlen("diff --git "));
420
a4acb0eb
LT
421 line += len;
422 size -= len;
423 linenr++;
424 for (offset = len ; size > 0 ; offset += len, size -= len, line += len, linenr++) {
425 static const struct opentry {
426 const char *str;
19c58fb8 427 int (*fn)(const char *, struct patch *);
a4acb0eb
LT
428 } optable[] = {
429 { "@@ -", gitdiff_hdrend },
430 { "--- ", gitdiff_oldname },
431 { "+++ ", gitdiff_newname },
432 { "old mode ", gitdiff_oldmode },
433 { "new mode ", gitdiff_newmode },
434 { "deleted file mode ", gitdiff_delete },
435 { "new file mode ", gitdiff_newfile },
436 { "copy from ", gitdiff_copysrc },
437 { "copy to ", gitdiff_copydst },
33f4d087
LT
438 { "rename old ", gitdiff_renamesrc },
439 { "rename new ", gitdiff_renamedst },
dc938417
LT
440 { "rename from ", gitdiff_renamesrc },
441 { "rename to ", gitdiff_renamedst },
a4acb0eb 442 { "similarity index ", gitdiff_similarity },
70aadac0 443 { "dissimilarity index ", gitdiff_dissimilarity },
9a4a100e 444 { "", gitdiff_unrecognized },
a4acb0eb
LT
445 };
446 int i;
c1bb9350 447
c1bb9350 448 len = linelen(line, size);
a4acb0eb 449 if (!len || line[len-1] != '\n')
c1bb9350 450 break;
a4acb0eb
LT
451 for (i = 0; i < sizeof(optable) / sizeof(optable[0]); i++) {
452 const struct opentry *p = optable + i;
453 int oplen = strlen(p->str);
454 if (len < oplen || memcmp(p->str, line, oplen))
455 continue;
19c58fb8 456 if (p->fn(line + oplen, patch) < 0)
a4acb0eb 457 return offset;
9a4a100e 458 break;
a4acb0eb 459 }
c1bb9350
LT
460 }
461
a4acb0eb 462 return offset;
c1bb9350
LT
463}
464
fab2c257 465static int parse_num(const char *line, unsigned long *p)
46979f56
LT
466{
467 char *ptr;
fab2c257
LT
468
469 if (!isdigit(*line))
470 return 0;
471 *p = strtoul(line, &ptr, 10);
472 return ptr - line;
473}
474
475static int parse_range(const char *line, int len, int offset, const char *expect,
476 unsigned long *p1, unsigned long *p2)
477{
46979f56
LT
478 int digits, ex;
479
480 if (offset < 0 || offset >= len)
481 return -1;
482 line += offset;
483 len -= offset;
484
fab2c257
LT
485 digits = parse_num(line, p1);
486 if (!digits)
46979f56 487 return -1;
46979f56
LT
488
489 offset += digits;
490 line += digits;
491 len -= digits;
492
fab2c257
LT
493 *p2 = *p1;
494 if (*line == ',') {
495 digits = parse_num(line+1, p2);
496 if (!digits)
497 return -1;
498
499 offset += digits+1;
500 line += digits+1;
501 len -= digits+1;
502 }
503
46979f56
LT
504 ex = strlen(expect);
505 if (ex > len)
506 return -1;
507 if (memcmp(line, expect, ex))
508 return -1;
509
510 return offset + ex;
511}
512
513/*
514 * Parse a unified diff fragment header of the
515 * form "@@ -a,b +c,d @@"
516 */
19c58fb8 517static int parse_fragment_header(char *line, int len, struct fragment *fragment)
46979f56
LT
518{
519 int offset;
520
521 if (!len || line[len-1] != '\n')
522 return -1;
523
524 /* Figure out the number of lines in a fragment */
fab2c257
LT
525 offset = parse_range(line, len, 4, " +", &fragment->oldpos, &fragment->oldlines);
526 offset = parse_range(line, len, offset, " @@", &fragment->newpos, &fragment->newlines);
46979f56
LT
527
528 return offset;
529}
530
19c58fb8 531static int find_header(char *line, unsigned long size, int *hdrsize, struct patch *patch)
c1bb9350
LT
532{
533 unsigned long offset, len;
534
19c58fb8
LT
535 patch->is_rename = patch->is_copy = 0;
536 patch->is_new = patch->is_delete = -1;
537 patch->old_mode = patch->new_mode = 0;
538 patch->old_name = patch->new_name = NULL;
46979f56 539 for (offset = 0; size > 0; offset += len, size -= len, line += len, linenr++) {
c1bb9350
LT
540 unsigned long nextlen;
541
542 len = linelen(line, size);
543 if (!len)
544 break;
545
546 /* Testing this early allows us to take a few shortcuts.. */
547 if (len < 6)
548 continue;
46979f56
LT
549
550 /*
551 * Make sure we don't find any unconnected patch fragmants.
552 * That's a sign that we didn't find a header, and that a
553 * patch has become corrupted/broken up.
554 */
555 if (!memcmp("@@ -", line, 4)) {
19c58fb8
LT
556 struct fragment dummy;
557 if (parse_fragment_header(line, len, &dummy) < 0)
46979f56
LT
558 continue;
559 error("patch fragment without header at line %d: %.*s", linenr, len-1, line);
560 }
561
c1bb9350
LT
562 if (size < len + 6)
563 break;
564
565 /*
566 * Git patch? It might not have a real patch, just a rename
567 * or mode change, so we handle that specially
568 */
569 if (!memcmp("diff --git ", line, 11)) {
19c58fb8 570 int git_hdr_len = parse_git_header(line, len, size, patch);
c1bb9350
LT
571 if (git_hdr_len < 0)
572 continue;
5041aa70 573 if (!patch->old_name && !patch->new_name)
33f4d087 574 die("git diff header lacks filename information (line %d)", linenr);
a4acb0eb 575 *hdrsize = git_hdr_len;
c1bb9350
LT
576 return offset;
577 }
578
579 /** --- followed by +++ ? */
580 if (memcmp("--- ", line, 4) || memcmp("+++ ", line + len, 4))
581 continue;
582
583 /*
584 * We only accept unified patches, so we want it to
585 * at least have "@@ -a,b +c,d @@\n", which is 14 chars
586 * minimum
587 */
588 nextlen = linelen(line + len, size - len);
589 if (size < nextlen + 14 || memcmp("@@ -", line + len + nextlen, 4))
590 continue;
591
592 /* Ok, we'll consider it a patch */
19c58fb8 593 parse_traditional_patch(line, line+len, patch);
c1bb9350 594 *hdrsize = len + nextlen;
46979f56 595 linenr += 2;
c1bb9350
LT
596 return offset;
597 }
598 return -1;
599}
600
c1bb9350
LT
601/*
602 * Parse a unified diff. Note that this really needs
603 * to parse each fragment separately, since the only
604 * way to know the difference between a "---" that is
605 * part of a patch, and a "---" that starts the next
606 * patch is to look at the line counts..
607 */
19c58fb8 608static int parse_fragment(char *line, unsigned long size, struct patch *patch, struct fragment *fragment)
c1bb9350 609{
3f40315a 610 int added, deleted;
c1bb9350 611 int len = linelen(line, size), offset;
30996652 612 unsigned long oldlines, newlines;
c1bb9350 613
19c58fb8 614 offset = parse_fragment_header(line, len, fragment);
c1bb9350
LT
615 if (offset < 0)
616 return -1;
19c58fb8
LT
617 oldlines = fragment->oldlines;
618 newlines = fragment->newlines;
c1bb9350 619
30996652
LT
620 if (patch->is_new < 0) {
621 patch->is_new = !oldlines;
622 if (!oldlines)
623 patch->old_name = NULL;
624 }
625 if (patch->is_delete < 0) {
626 patch->is_delete = !newlines;
627 if (!newlines)
628 patch->new_name = NULL;
629 }
630
631 if (patch->is_new != !oldlines)
632 return error("new file depends on old contents");
633 if (patch->is_delete != !newlines)
634 return error("deleted file still has contents");
a4acb0eb 635
c1bb9350
LT
636 /* Parse the thing.. */
637 line += len;
638 size -= len;
46979f56 639 linenr++;
3f40315a 640 added = deleted = 0;
46979f56 641 for (offset = len; size > 0; offset += len, size -= len, line += len, linenr++) {
c1bb9350
LT
642 if (!oldlines && !newlines)
643 break;
644 len = linelen(line, size);
645 if (!len || line[len-1] != '\n')
646 return -1;
647 switch (*line) {
648 default:
649 return -1;
650 case ' ':
651 oldlines--;
652 newlines--;
653 break;
654 case '-':
3f40315a 655 deleted++;
c1bb9350
LT
656 oldlines--;
657 break;
658 case '+':
3f40315a 659 added++;
c1bb9350
LT
660 newlines--;
661 break;
fab2c257
LT
662 /* We allow "\ No newline at end of file" */
663 case '\\':
3cca928d
LT
664 if (len < 12 || memcmp(line, "\\ No newline", 12))
665 return -1;
fab2c257 666 break;
c1bb9350
LT
667 }
668 }
3f40315a
LT
669 patch->lines_added += added;
670 patch->lines_deleted += deleted;
c1bb9350
LT
671 return offset;
672}
673
19c58fb8 674static int parse_single_patch(char *line, unsigned long size, struct patch *patch)
c1bb9350
LT
675{
676 unsigned long offset = 0;
19c58fb8 677 struct fragment **fragp = &patch->fragments;
c1bb9350
LT
678
679 while (size > 4 && !memcmp(line, "@@ -", 4)) {
19c58fb8
LT
680 struct fragment *fragment;
681 int len;
682
683 fragment = xmalloc(sizeof(*fragment));
684 memset(fragment, 0, sizeof(*fragment));
685 len = parse_fragment(line, size, patch, fragment);
c1bb9350 686 if (len <= 0)
46979f56 687 die("corrupt patch at line %d", linenr);
c1bb9350 688
19c58fb8
LT
689 fragment->patch = line;
690 fragment->size = len;
691
692 *fragp = fragment;
693 fragp = &fragment->next;
c1bb9350
LT
694
695 offset += len;
696 line += len;
697 size -= len;
698 }
699 return offset;
700}
701
19c58fb8 702static int parse_chunk(char *buffer, unsigned long size, struct patch *patch)
c1bb9350
LT
703{
704 int hdrsize, patchsize;
19c58fb8 705 int offset = find_header(buffer, size, &hdrsize, patch);
c1bb9350
LT
706
707 if (offset < 0)
708 return offset;
c1bb9350 709
19c58fb8 710 patchsize = parse_single_patch(buffer + offset + hdrsize, size - offset - hdrsize, patch);
c1bb9350
LT
711
712 return offset + hdrsize + patchsize;
713}
714
3f40315a
LT
715const char pluses[] = "++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++";
716const char minuses[]= "----------------------------------------------------------------------";
717
718static void show_stats(struct patch *patch)
719{
720 char *name = patch->old_name;
95bedc9e 721 int len, max, add, del, total;
3f40315a 722
5041aa70 723 if (!name)
3f40315a
LT
724 name = patch->new_name;
725
726 /*
727 * "scale" the filename
728 */
729 len = strlen(name);
730 max = max_len;
731 if (max > 50)
732 max = 50;
733 if (len > max)
734 name += len - max;
735 len = max;
736
737 /*
738 * scale the add/delete
739 */
740 max = max_change;
741 if (max + len > 70)
742 max = 70 - len;
95bedc9e
LT
743
744 add = patch->lines_added;
745 del = patch->lines_deleted;
746 total = add + del;
747
748 total = (total * max + max_change / 2) / max_change;
749 add = (add * max + max_change / 2) / max_change;
750 del = total - add;
3f40315a
LT
751 printf(" %-*s |%5d %.*s%.*s\n",
752 len, name, patch->lines_added + patch->lines_deleted,
753 add, pluses, del, minuses);
754}
755
3cca928d
LT
756static int read_old_data(struct stat *st, const char *path, void *buf, unsigned long size)
757{
758 int fd;
759 unsigned long got;
760
761 switch (st->st_mode & S_IFMT) {
762 case S_IFLNK:
763 return readlink(path, buf, size);
764 case S_IFREG:
765 fd = open(path, O_RDONLY);
766 if (fd < 0)
767 return error("unable to open %s", path);
768 got = 0;
769 for (;;) {
770 int ret = read(fd, buf + got, size - got);
771 if (ret < 0) {
772 if (errno == EAGAIN)
773 continue;
774 break;
775 }
776 if (!ret)
777 break;
778 got += ret;
779 }
780 close(fd);
781 return got;
782
783 default:
784 return -1;
785 }
786}
787
788static int find_offset(const char *buf, unsigned long size, const char *fragment, unsigned long fragsize, int line)
789{
6e7c92a9
LT
790 int i;
791 unsigned long start, backwards, forwards;
3cca928d
LT
792
793 if (fragsize > size)
794 return -1;
795
796 start = 0;
797 if (line > 1) {
3cca928d 798 unsigned long offset = 0;
6e7c92a9
LT
799 i = line-1;
800 while (offset + fragsize <= size) {
3cca928d
LT
801 if (buf[offset++] == '\n') {
802 start = offset;
6e7c92a9 803 if (!--i)
3cca928d
LT
804 break;
805 }
806 }
807 }
808
809 /* Exact line number? */
810 if (!memcmp(buf + start, fragment, fragsize))
811 return start;
812
6e7c92a9
LT
813 /*
814 * There's probably some smart way to do this, but I'll leave
815 * that to the smart and beautiful people. I'm simple and stupid.
816 */
817 backwards = start;
818 forwards = start;
819 for (i = 0; ; i++) {
820 unsigned long try;
821 int n;
822
823 /* "backward" */
824 if (i & 1) {
825 if (!backwards) {
826 if (forwards + fragsize > size)
827 break;
828 continue;
829 }
830 do {
831 --backwards;
832 } while (backwards && buf[backwards-1] != '\n');
833 try = backwards;
834 } else {
835 while (forwards + fragsize <= size) {
836 if (buf[forwards++] == '\n')
837 break;
838 }
839 try = forwards;
840 }
841
842 if (try + fragsize > size)
843 continue;
844 if (memcmp(buf + try, fragment, fragsize))
845 continue;
846 n = (i >> 1)+1;
847 if (i & 1)
848 n = -n;
849 fprintf(stderr, "Fragment applied at offset %d\n", n);
850 return try;
851 }
852
3cca928d
LT
853 /*
854 * We should start searching forward and backward.
855 */
856 return -1;
857}
858
6e7c92a9
LT
859struct buffer_desc {
860 char *buffer;
861 unsigned long size;
862 unsigned long alloc;
863};
864
865static int apply_one_fragment(struct buffer_desc *desc, struct fragment *frag)
3cca928d 866{
6e7c92a9 867 char *buf = desc->buffer;
3cca928d
LT
868 const char *patch = frag->patch;
869 int offset, size = frag->size;
870 char *old = xmalloc(size);
871 char *new = xmalloc(size);
872 int oldsize = 0, newsize = 0;
873
874 while (size > 0) {
875 int len = linelen(patch, size);
876 int plen;
877
878 if (!len)
879 break;
880
881 /*
882 * "plen" is how much of the line we should use for
883 * the actual patch data. Normally we just remove the
884 * first character on the line, but if the line is
885 * followed by "\ No newline", then we also remove the
886 * last one (which is the newline, of course).
887 */
888 plen = len-1;
889 if (len > size && patch[len] == '\\')
890 plen--;
891 switch (*patch) {
892 case ' ':
893 case '-':
894 memcpy(old + oldsize, patch + 1, plen);
895 oldsize += plen;
896 if (*patch == '-')
897 break;
898 /* Fall-through for ' ' */
899 case '+':
900 memcpy(new + newsize, patch + 1, plen);
901 newsize += plen;
902 break;
903 case '@': case '\\':
904 /* Ignore it, we already handled it */
905 break;
906 default:
907 return -1;
908 }
909 patch += len;
910 size -= len;
911 }
912
6e7c92a9 913 offset = find_offset(buf, desc->size, old, oldsize, frag->newpos);
3cca928d 914 if (offset >= 0) {
6e7c92a9
LT
915 int diff = newsize - oldsize;
916 unsigned long size = desc->size + diff;
917 unsigned long alloc = desc->alloc;
918
919 if (size > alloc) {
920 alloc = size + 8192;
921 desc->alloc = alloc;
922 buf = xrealloc(buf, alloc);
923 desc->buffer = buf;
924 }
925 desc->size = size;
926 memmove(buf + offset + newsize, buf + offset + oldsize, size - offset - newsize);
927 memcpy(buf + offset, new, newsize);
3cca928d
LT
928 offset = 0;
929 }
930
931 free(old);
932 free(new);
933 return offset;
934}
935
6e7c92a9 936static int apply_fragments(struct buffer_desc *desc, struct patch *patch)
3cca928d
LT
937{
938 struct fragment *frag = patch->fragments;
939
940 while (frag) {
6e7c92a9 941 if (apply_one_fragment(desc, frag) < 0)
3cca928d
LT
942 return error("patch failed: %s:%d", patch->old_name, frag->oldpos);
943 frag = frag->next;
944 }
30996652 945 return 0;
3cca928d
LT
946}
947
948static int apply_data(struct patch *patch, struct stat *st)
949{
6e7c92a9
LT
950 char *buf;
951 unsigned long size, alloc;
952 struct buffer_desc desc;
3cca928d 953
30996652
LT
954 size = 0;
955 alloc = 0;
956 buf = NULL;
957 if (patch->old_name) {
958 size = st->st_size;
959 alloc = size + 8192;
960 buf = xmalloc(alloc);
961 if (read_old_data(st, patch->old_name, buf, alloc) != size)
962 return error("read of %s failed", patch->old_name);
963 }
6e7c92a9
LT
964
965 desc.size = size;
966 desc.alloc = alloc;
967 desc.buffer = buf;
968 if (apply_fragments(&desc, patch) < 0)
3cca928d 969 return -1;
6e7c92a9
LT
970 patch->result = desc.buffer;
971 patch->resultsize = desc.size;
5aa7d94c
LT
972
973 if (patch->is_delete && patch->resultsize)
974 return error("removal patch leaves file contents");
975
3cca928d
LT
976 return 0;
977}
978
a577284a 979static int check_patch(struct patch *patch)
fab2c257 980{
a577284a 981 struct stat st;
fab2c257
LT
982 const char *old_name = patch->old_name;
983 const char *new_name = patch->new_name;
984
985 if (old_name) {
a577284a
LT
986 int changed;
987
a577284a
LT
988 if (lstat(old_name, &st) < 0)
989 return error("%s: %s\n", strerror(errno));
3cca928d
LT
990 if (check_index) {
991 int pos = cache_name_pos(old_name, strlen(old_name));
992 if (pos < 0)
993 return error("%s: does not exist in index", old_name);
994 changed = ce_match_stat(active_cache[pos], &st);
995 if (changed)
996 return error("%s: does not match index", old_name);
997 }
998 if (patch->is_new < 0)
999 patch->is_new = 0;
a577284a
LT
1000 if (!patch->old_mode)
1001 patch->old_mode = st.st_mode;
3cca928d
LT
1002 if ((st.st_mode ^ patch->old_mode) & S_IFMT)
1003 return error("%s: wrong type", old_name);
1004 if (st.st_mode != patch->old_mode)
1005 fprintf(stderr, "warning: %s has type %o, expected %o\n",
1006 old_name, st.st_mode, patch->old_mode);
fab2c257 1007 }
a577284a 1008
fab2c257 1009 if (new_name && (patch->is_new | patch->is_rename | patch->is_copy)) {
3cca928d 1010 if (check_index && cache_name_pos(new_name, strlen(new_name)) >= 0)
a577284a
LT
1011 return error("%s: already exists in index", new_name);
1012 if (!lstat(new_name, &st))
1013 return error("%s: already exists in working directory", new_name);
1014 if (errno != ENOENT)
1015 return error("%s: %s", new_name, strerror(errno));
5aa7d94c
LT
1016 if (!patch->new_mode)
1017 patch->new_mode = S_IFREG | 0644;
fab2c257 1018 }
3cca928d
LT
1019
1020 if (new_name && old_name) {
1021 int same = !strcmp(old_name, new_name);
1022 if (!patch->new_mode)
1023 patch->new_mode = patch->old_mode;
1024 if ((patch->old_mode ^ patch->new_mode) & S_IFMT)
1025 return error("new mode (%o) of %s does not match old mode (%o)%s%s",
1026 patch->new_mode, new_name, patch->old_mode,
1027 same ? "" : " of ", same ? "" : old_name);
1028 }
1029
1030 if (apply_data(patch, &st) < 0)
1031 return error("%s: patch does not apply", old_name);
a577284a 1032 return 0;
fab2c257
LT
1033}
1034
a577284a 1035static int check_patch_list(struct patch *patch)
19c58fb8 1036{
a577284a
LT
1037 int error = 0;
1038
1039 for (;patch ; patch = patch->next)
1040 error |= check_patch(patch);
1041 return error;
1042}
1043
1044static void show_file(int c, unsigned int mode, const char *name)
1045{
1046 printf("%c %o %s\n", c, mode, name);
1047}
3f40315a 1048
a577284a
LT
1049static void show_file_list(struct patch *patch)
1050{
1051 for (;patch ; patch = patch->next) {
1052 if (patch->is_rename) {
1053 show_file('-', patch->old_mode, patch->old_name);
1054 show_file('+', patch->new_mode, patch->new_name);
1055 continue;
1056 }
1057 if (patch->is_copy || patch->is_new) {
1058 show_file('+', patch->new_mode, patch->new_name);
1059 continue;
1060 }
1061 if (patch->is_delete) {
1062 show_file('-', patch->old_mode, patch->old_name);
1063 continue;
1064 }
1065 if (patch->old_mode && patch->new_mode && patch->old_mode != patch->new_mode) {
1066 printf("M %o:%o %s\n", patch->old_mode, patch->new_mode, patch->old_name);
1067 continue;
19c58fb8 1068 }
a577284a
LT
1069 printf("M %o %s\n", patch->old_mode, patch->old_name);
1070 }
1071}
fab2c257 1072
a577284a
LT
1073static void stat_patch_list(struct patch *patch)
1074{
1075 int files, adds, dels;
1076
1077 for (files = adds = dels = 0 ; patch ; patch = patch->next) {
1078 files++;
1079 adds += patch->lines_added;
1080 dels += patch->lines_deleted;
1081 show_stats(patch);
1082 }
1083
1084 printf(" %d files changed, %d insertions(+), %d deletions(-)\n", files, adds, dels);
3f40315a
LT
1085}
1086
1087static void patch_stats(struct patch *patch)
1088{
1089 int lines = patch->lines_added + patch->lines_deleted;
1090
1091 if (lines > max_change)
1092 max_change = lines;
1093 if (patch->old_name) {
1094 int len = strlen(patch->old_name);
1095 if (len > max_len)
1096 max_len = len;
1097 }
1098 if (patch->new_name) {
1099 int len = strlen(patch->new_name);
1100 if (len > max_len)
1101 max_len = len;
1102 }
19c58fb8
LT
1103}
1104
5aa7d94c
LT
1105static void remove_file(struct patch *patch)
1106{
1107 if (write_index) {
1108 if (remove_file_from_cache(patch->old_name) < 0)
1109 die("unable to remove %s from index", patch->old_name);
1110 }
1111 unlink(patch->old_name);
1112}
1113
1114static void add_index_file(const char *path, unsigned mode, void *buf, unsigned long size)
1115{
1116 struct stat st;
1117 struct cache_entry *ce;
1118 int namelen = strlen(path);
1119 unsigned ce_size = cache_entry_size(namelen);
1120
1121 if (!write_index)
1122 return;
1123
1124 ce = xmalloc(ce_size);
1125 memset(ce, 0, ce_size);
1126 memcpy(ce->name, path, namelen);
1127 ce->ce_mode = create_ce_mode(mode);
1128 ce->ce_flags = htons(namelen);
1129 if (lstat(path, &st) < 0)
1130 die("unable to stat newly created file %s", path);
1131 fill_stat_cache_info(ce, &st);
1132 if (write_sha1_file(buf, size, "blob", ce->sha1) < 0)
1133 die("unable to create backing store for newly created file %s", path);
1134 if (add_cache_entry(ce, ADD_CACHE_OK_TO_ADD) < 0)
1135 die("unable to add cache entry for %s", path);
1136}
1137
1138static void create_file(struct patch *patch)
1139{
1140 const char *path = patch->new_name;
1141 unsigned mode = patch->new_mode;
1142 unsigned long size = patch->resultsize;
1143 char *buf = patch->result;
1144
1145 if (!mode)
1146 mode = S_IFREG | 0644;
1147 if (S_ISREG(mode)) {
1148 int fd;
1149 mode = (mode & 0100) ? 0777 : 0666;
1150 fd = open(path, O_WRONLY | O_CREAT | O_TRUNC, mode);
1151 if (fd < 0)
1152 die("unable to create file %s (%s)", path, strerror(errno));
1153 if (write(fd, buf, size) != size)
1154 die("unable to write file %s", path);
1155 close(fd);
1156 add_index_file(path, mode, buf, size);
1157 return;
1158 }
1159 if (S_ISLNK(mode)) {
1160 if (size && buf[size-1] == '\n')
1161 size--;
1162 buf[size] = 0;
1163 if (symlink(buf, path) < 0)
1164 die("unable to write symlink %s", path);
1165 add_index_file(path, mode, buf, size);
1166 return;
1167 }
1168 die("unable to write file mode %o", mode);
1169}
1170
1171static void write_out_one_result(struct patch *patch)
1172{
1173 if (patch->is_delete > 0) {
1174 remove_file(patch);
1175 return;
1176 }
1177 if (patch->is_new > 0 || patch->is_copy) {
1178 create_file(patch);
1179 return;
1180 }
1181 /*
1182 * Rename or modification boils down to the same
1183 * thing: remove the old, write the new
1184 */
1185 remove_file(patch);
1186 create_file(patch);
1187}
1188
1189static void write_out_results(struct patch *list)
1190{
f7b79707
LT
1191 if (!list)
1192 die("No changes");
1193
5aa7d94c
LT
1194 while (list) {
1195 write_out_one_result(list);
1196 list = list->next;
1197 }
1198}
1199
1200static struct cache_file cache_file;
1201
c1bb9350
LT
1202static int apply_patch(int fd)
1203{
5aa7d94c 1204 int newfd;
c1bb9350
LT
1205 unsigned long offset, size;
1206 char *buffer = read_patch_file(fd, &size);
19c58fb8 1207 struct patch *list = NULL, **listp = &list;
c1bb9350
LT
1208
1209 if (!buffer)
1210 return -1;
1211 offset = 0;
1212 while (size > 0) {
19c58fb8
LT
1213 struct patch *patch;
1214 int nr;
1215
1216 patch = xmalloc(sizeof(*patch));
1217 memset(patch, 0, sizeof(*patch));
1218 nr = parse_chunk(buffer + offset, size, patch);
c1bb9350
LT
1219 if (nr < 0)
1220 break;
3f40315a 1221 patch_stats(patch);
19c58fb8
LT
1222 *listp = patch;
1223 listp = &patch->next;
c1bb9350
LT
1224 offset += nr;
1225 size -= nr;
1226 }
19c58fb8 1227
5aa7d94c
LT
1228 newfd = -1;
1229 write_index = check_index && apply;
1230 if (write_index)
1231 newfd = hold_index_file_for_update(&cache_file, get_index_file());
1232 if (check_index) {
1233 if (read_cache() < 0)
1234 die("unable to read index file");
1235 }
1236
a577284a
LT
1237 if ((check || apply) && check_patch_list(list) < 0)
1238 exit(1);
1239
5aa7d94c
LT
1240 if (apply)
1241 write_out_results(list);
1242
1243 if (write_index) {
1244 if (write_cache(newfd, active_cache, active_nr) ||
1245 commit_index_file(&cache_file))
1246 die("Unable to write new cachefile");
1247 }
1248
a577284a
LT
1249 if (show_files)
1250 show_file_list(list);
1251
1252 if (diffstat)
1253 stat_patch_list(list);
19c58fb8 1254
c1bb9350
LT
1255 free(buffer);
1256 return 0;
1257}
1258
1259int main(int argc, char **argv)
1260{
1261 int i;
4dfdbe10 1262 int read_stdin = 1;
c1bb9350 1263
c1bb9350
LT
1264 for (i = 1; i < argc; i++) {
1265 const char *arg = argv[i];
1266 int fd;
1267
1268 if (!strcmp(arg, "-")) {
1269 apply_patch(0);
4dfdbe10 1270 read_stdin = 0;
c1bb9350
LT
1271 continue;
1272 }
1273 if (!strcmp(arg, "--no-merge")) {
1274 merge_patch = 0;
1275 continue;
1276 }
fab2c257 1277 if (!strcmp(arg, "--stat")) {
a577284a 1278 apply = 0;
fab2c257
LT
1279 diffstat = 1;
1280 continue;
1281 }
a577284a
LT
1282 if (!strcmp(arg, "--check")) {
1283 apply = 0;
1284 check = 1;
1285 continue;
1286 }
3cca928d
LT
1287 if (!strcmp(arg, "--index")) {
1288 check_index = 1;
1289 continue;
1290 }
a577284a
LT
1291 if (!strcmp(arg, "--show-files")) {
1292 show_files = 1;
1293 continue;
1294 }
c1bb9350
LT
1295 fd = open(arg, O_RDONLY);
1296 if (fd < 0)
1297 usage(apply_usage);
4dfdbe10 1298 read_stdin = 0;
c1bb9350
LT
1299 apply_patch(fd);
1300 close(fd);
1301 }
4dfdbe10
LT
1302 if (read_stdin)
1303 apply_patch(0);
c1bb9350
LT
1304 return 0;
1305}