Make zlib compression level configurable, and change default.
[git/git.git] / config.c
1 /*
2 * GIT - The information manager from hell
3 *
4 * Copyright (C) Linus Torvalds, 2005
5 * Copyright (C) Johannes Schindelin, 2005
6 *
7 */
8 #include "cache.h"
9 #include <regex.h>
10
11 #define MAXNAME (256)
12
13 static FILE *config_file;
14 static const char *config_file_name;
15 static int config_linenr;
16 static int get_next_char(void)
17 {
18 int c;
19 FILE *f;
20
21 c = '\n';
22 if ((f = config_file) != NULL) {
23 c = fgetc(f);
24 if (c == '\r') {
25 /* DOS like systems */
26 c = fgetc(f);
27 if (c != '\n') {
28 ungetc(c, f);
29 c = '\r';
30 }
31 }
32 if (c == '\n')
33 config_linenr++;
34 if (c == EOF) {
35 config_file = NULL;
36 c = '\n';
37 }
38 }
39 return c;
40 }
41
42 static char *parse_value(void)
43 {
44 static char value[1024];
45 int quote = 0, comment = 0, len = 0, space = 0;
46
47 for (;;) {
48 int c = get_next_char();
49 if (len >= sizeof(value))
50 return NULL;
51 if (c == '\n') {
52 if (quote)
53 return NULL;
54 value[len] = 0;
55 return value;
56 }
57 if (comment)
58 continue;
59 if (isspace(c) && !quote) {
60 space = 1;
61 continue;
62 }
63 if (!quote) {
64 if (c == ';' || c == '#') {
65 comment = 1;
66 continue;
67 }
68 }
69 if (space) {
70 if (len)
71 value[len++] = ' ';
72 space = 0;
73 }
74 if (c == '\\') {
75 c = get_next_char();
76 switch (c) {
77 case '\n':
78 continue;
79 case 't':
80 c = '\t';
81 break;
82 case 'b':
83 c = '\b';
84 break;
85 case 'n':
86 c = '\n';
87 break;
88 /* Some characters escape as themselves */
89 case '\\': case '"':
90 break;
91 /* Reject unknown escape sequences */
92 default:
93 return NULL;
94 }
95 value[len++] = c;
96 continue;
97 }
98 if (c == '"') {
99 quote = 1-quote;
100 continue;
101 }
102 value[len++] = c;
103 }
104 }
105
106 static int get_value(config_fn_t fn, char *name, unsigned int len)
107 {
108 int c;
109 char *value;
110
111 /* Get the full name */
112 for (;;) {
113 c = get_next_char();
114 if (c == EOF)
115 break;
116 if (!isalnum(c))
117 break;
118 name[len++] = tolower(c);
119 if (len >= MAXNAME)
120 return -1;
121 }
122 name[len] = 0;
123 while (c == ' ' || c == '\t')
124 c = get_next_char();
125
126 value = NULL;
127 if (c != '\n') {
128 if (c != '=')
129 return -1;
130 value = parse_value();
131 if (!value)
132 return -1;
133 }
134 return fn(name, value);
135 }
136
137 static int get_extended_base_var(char *name, int baselen, int c)
138 {
139 do {
140 if (c == '\n')
141 return -1;
142 c = get_next_char();
143 } while (isspace(c));
144
145 /* We require the format to be '[base "extension"]' */
146 if (c != '"')
147 return -1;
148 name[baselen++] = '.';
149
150 for (;;) {
151 int c = get_next_char();
152 if (c == '\n')
153 return -1;
154 if (c == '"')
155 break;
156 if (c == '\\') {
157 c = get_next_char();
158 if (c == '\n')
159 return -1;
160 }
161 name[baselen++] = c;
162 if (baselen > MAXNAME / 2)
163 return -1;
164 }
165
166 /* Final ']' */
167 if (get_next_char() != ']')
168 return -1;
169 return baselen;
170 }
171
172 static int get_base_var(char *name)
173 {
174 int baselen = 0;
175
176 for (;;) {
177 int c = get_next_char();
178 if (c == EOF)
179 return -1;
180 if (c == ']')
181 return baselen;
182 if (isspace(c))
183 return get_extended_base_var(name, baselen, c);
184 if (!isalnum(c) && c != '.')
185 return -1;
186 if (baselen > MAXNAME / 2)
187 return -1;
188 name[baselen++] = tolower(c);
189 }
190 }
191
192 static int git_parse_file(config_fn_t fn)
193 {
194 int comment = 0;
195 int baselen = 0;
196 static char var[MAXNAME];
197
198 for (;;) {
199 int c = get_next_char();
200 if (c == '\n') {
201 /* EOF? */
202 if (!config_file)
203 return 0;
204 comment = 0;
205 continue;
206 }
207 if (comment || isspace(c))
208 continue;
209 if (c == '#' || c == ';') {
210 comment = 1;
211 continue;
212 }
213 if (c == '[') {
214 baselen = get_base_var(var);
215 if (baselen <= 0)
216 break;
217 var[baselen++] = '.';
218 var[baselen] = 0;
219 continue;
220 }
221 if (!isalpha(c))
222 break;
223 var[baselen] = tolower(c);
224 if (get_value(fn, var, baselen+1) < 0)
225 break;
226 }
227 die("bad config file line %d in %s", config_linenr, config_file_name);
228 }
229
230 int git_config_int(const char *name, const char *value)
231 {
232 if (value && *value) {
233 char *end;
234 int val = strtol(value, &end, 0);
235 if (!*end)
236 return val;
237 }
238 die("bad config value for '%s' in %s", name, config_file_name);
239 }
240
241 int git_config_bool(const char *name, const char *value)
242 {
243 if (!value)
244 return 1;
245 if (!*value)
246 return 0;
247 if (!strcasecmp(value, "true"))
248 return 1;
249 if (!strcasecmp(value, "false"))
250 return 0;
251 return git_config_int(name, value) != 0;
252 }
253
254 int git_default_config(const char *var, const char *value)
255 {
256 /* This needs a better name */
257 if (!strcmp(var, "core.filemode")) {
258 trust_executable_bit = git_config_bool(var, value);
259 return 0;
260 }
261
262 if (!strcmp(var, "core.ignorestat")) {
263 assume_unchanged = git_config_bool(var, value);
264 return 0;
265 }
266
267 if (!strcmp(var, "core.prefersymlinkrefs")) {
268 prefer_symlink_refs = git_config_bool(var, value);
269 return 0;
270 }
271
272 if (!strcmp(var, "core.logallrefupdates")) {
273 log_all_ref_updates = git_config_bool(var, value);
274 return 0;
275 }
276
277 if (!strcmp(var, "core.warnambiguousrefs")) {
278 warn_ambiguous_refs = git_config_bool(var, value);
279 return 0;
280 }
281
282 if (!strcmp(var, "core.compression")) {
283 int level = git_config_int(var, value);
284 if (level == -1)
285 level = Z_DEFAULT_COMPRESSION;
286 else if (level < 0 || level > Z_BEST_COMPRESSION)
287 die("bad zlib compression level %d", level);
288 zlib_compression_level = level;
289 return 0;
290 }
291
292 if (!strcmp(var, "user.name")) {
293 strlcpy(git_default_name, value, sizeof(git_default_name));
294 return 0;
295 }
296
297 if (!strcmp(var, "user.email")) {
298 strlcpy(git_default_email, value, sizeof(git_default_email));
299 return 0;
300 }
301
302 if (!strcmp(var, "i18n.commitencoding")) {
303 strlcpy(git_commit_encoding, value, sizeof(git_commit_encoding));
304 return 0;
305 }
306
307 /* Add other config variables here and to Documentation/config.txt. */
308 return 0;
309 }
310
311 int git_config_from_file(config_fn_t fn, const char *filename)
312 {
313 int ret;
314 FILE *f = fopen(filename, "r");
315
316 ret = -1;
317 if (f) {
318 config_file = f;
319 config_file_name = filename;
320 config_linenr = 1;
321 ret = git_parse_file(fn);
322 fclose(f);
323 config_file_name = NULL;
324 }
325 return ret;
326 }
327
328 int git_config(config_fn_t fn)
329 {
330 int ret = 0;
331 char *repo_config = NULL;
332 const char *home = NULL, *filename;
333
334 /* $GIT_CONFIG makes git read _only_ the given config file,
335 * $GIT_CONFIG_LOCAL will make it process it in addition to the
336 * global config file, the same way it would the per-repository
337 * config file otherwise. */
338 filename = getenv("GIT_CONFIG");
339 if (!filename) {
340 home = getenv("HOME");
341 filename = getenv("GIT_CONFIG_LOCAL");
342 if (!filename)
343 filename = repo_config = strdup(git_path("config"));
344 }
345
346 if (home) {
347 char *user_config = strdup(mkpath("%s/.gitconfig", home));
348 if (!access(user_config, R_OK))
349 ret = git_config_from_file(fn, user_config);
350 free(user_config);
351 }
352
353 ret += git_config_from_file(fn, filename);
354 if (repo_config)
355 free(repo_config);
356 return ret;
357 }
358
359 /*
360 * Find all the stuff for git_config_set() below.
361 */
362
363 #define MAX_MATCHES 512
364
365 static struct {
366 int baselen;
367 char* key;
368 int do_not_match;
369 regex_t* value_regex;
370 int multi_replace;
371 off_t offset[MAX_MATCHES];
372 enum { START, SECTION_SEEN, SECTION_END_SEEN, KEY_SEEN } state;
373 int seen;
374 } store;
375
376 static int matches(const char* key, const char* value)
377 {
378 return !strcmp(key, store.key) &&
379 (store.value_regex == NULL ||
380 (store.do_not_match ^
381 !regexec(store.value_regex, value, 0, NULL, 0)));
382 }
383
384 static int store_aux(const char* key, const char* value)
385 {
386 switch (store.state) {
387 case KEY_SEEN:
388 if (matches(key, value)) {
389 if (store.seen == 1 && store.multi_replace == 0) {
390 fprintf(stderr,
391 "Warning: %s has multiple values\n",
392 key);
393 } else if (store.seen >= MAX_MATCHES) {
394 fprintf(stderr, "Too many matches\n");
395 return 1;
396 }
397
398 store.offset[store.seen] = ftell(config_file);
399 store.seen++;
400 }
401 break;
402 case SECTION_SEEN:
403 if (strncmp(key, store.key, store.baselen+1)) {
404 store.state = SECTION_END_SEEN;
405 break;
406 } else
407 /* do not increment matches: this is no match */
408 store.offset[store.seen] = ftell(config_file);
409 /* fallthru */
410 case SECTION_END_SEEN:
411 case START:
412 if (matches(key, value)) {
413 store.offset[store.seen] = ftell(config_file);
414 store.state = KEY_SEEN;
415 store.seen++;
416 } else {
417 if (strrchr(key, '.') - key == store.baselen &&
418 !strncmp(key, store.key, store.baselen)) {
419 store.state = SECTION_SEEN;
420 store.offset[store.seen] = ftell(config_file);
421 }
422 }
423 }
424 return 0;
425 }
426
427 static void store_write_section(int fd, const char* key)
428 {
429 const char *dot = strchr(key, '.');
430 int len1 = store.baselen, len2 = -1;
431
432 dot = strchr(key, '.');
433 if (dot) {
434 int dotlen = dot - key;
435 if (dotlen < len1) {
436 len2 = len1 - dotlen - 1;
437 len1 = dotlen;
438 }
439 }
440
441 write(fd, "[", 1);
442 write(fd, key, len1);
443 if (len2 >= 0) {
444 write(fd, " \"", 2);
445 while (--len2 >= 0) {
446 unsigned char c = *++dot;
447 if (c == '"')
448 write(fd, "\\", 1);
449 write(fd, &c, 1);
450 }
451 write(fd, "\"", 1);
452 }
453 write(fd, "]\n", 2);
454 }
455
456 static void store_write_pair(int fd, const char* key, const char* value)
457 {
458 int i;
459
460 write(fd, "\t", 1);
461 write(fd, key+store.baselen+1,
462 strlen(key+store.baselen+1));
463 write(fd, " = ", 3);
464 for (i = 0; value[i]; i++)
465 switch (value[i]) {
466 case '\n': write(fd, "\\n", 2); break;
467 case '\t': write(fd, "\\t", 2); break;
468 case '"': case '\\': write(fd, "\\", 1);
469 default: write(fd, value+i, 1);
470 }
471 write(fd, "\n", 1);
472 }
473
474 static int find_beginning_of_line(const char* contents, int size,
475 int offset_, int* found_bracket)
476 {
477 int equal_offset = size, bracket_offset = size;
478 int offset;
479
480 for (offset = offset_-2; offset > 0
481 && contents[offset] != '\n'; offset--)
482 switch (contents[offset]) {
483 case '=': equal_offset = offset; break;
484 case ']': bracket_offset = offset; break;
485 }
486 if (bracket_offset < equal_offset) {
487 *found_bracket = 1;
488 offset = bracket_offset+1;
489 } else
490 offset++;
491
492 return offset;
493 }
494
495 int git_config_set(const char* key, const char* value)
496 {
497 return git_config_set_multivar(key, value, NULL, 0);
498 }
499
500 /*
501 * If value==NULL, unset in (remove from) config,
502 * if value_regex!=NULL, disregard key/value pairs where value does not match.
503 * if multi_replace==0, nothing, or only one matching key/value is replaced,
504 * else all matching key/values (regardless how many) are removed,
505 * before the new pair is written.
506 *
507 * Returns 0 on success.
508 *
509 * This function does this:
510 *
511 * - it locks the config file by creating ".git/config.lock"
512 *
513 * - it then parses the config using store_aux() as validator to find
514 * the position on the key/value pair to replace. If it is to be unset,
515 * it must be found exactly once.
516 *
517 * - the config file is mmap()ed and the part before the match (if any) is
518 * written to the lock file, then the changed part and the rest.
519 *
520 * - the config file is removed and the lock file rename()d to it.
521 *
522 */
523 int git_config_set_multivar(const char* key, const char* value,
524 const char* value_regex, int multi_replace)
525 {
526 int i, dot;
527 int fd = -1, in_fd;
528 int ret;
529 char* config_filename;
530 char* lock_file;
531 const char* last_dot = strrchr(key, '.');
532
533 config_filename = getenv("GIT_CONFIG");
534 if (!config_filename) {
535 config_filename = getenv("GIT_CONFIG_LOCAL");
536 if (!config_filename)
537 config_filename = git_path("config");
538 }
539 config_filename = strdup(config_filename);
540 lock_file = strdup(mkpath("%s.lock", config_filename));
541
542 /*
543 * Since "key" actually contains the section name and the real
544 * key name separated by a dot, we have to know where the dot is.
545 */
546
547 if (last_dot == NULL) {
548 fprintf(stderr, "key does not contain a section: %s\n", key);
549 ret = 2;
550 goto out_free;
551 }
552 store.baselen = last_dot - key;
553
554 store.multi_replace = multi_replace;
555
556 /*
557 * Validate the key and while at it, lower case it for matching.
558 */
559 store.key = (char*)malloc(strlen(key)+1);
560 dot = 0;
561 for (i = 0; key[i]; i++) {
562 unsigned char c = key[i];
563 if (c == '.')
564 dot = 1;
565 /* Leave the extended basename untouched.. */
566 if (!dot || i > store.baselen) {
567 if (!isalnum(c) || (i == store.baselen+1 && !isalpha(c))) {
568 fprintf(stderr, "invalid key: %s\n", key);
569 free(store.key);
570 ret = 1;
571 goto out_free;
572 }
573 c = tolower(c);
574 }
575 store.key[i] = c;
576 }
577 store.key[i] = 0;
578
579 /*
580 * The lock_file serves a purpose in addition to locking: the new
581 * contents of .git/config will be written into it.
582 */
583 fd = open(lock_file, O_WRONLY | O_CREAT | O_EXCL, 0666);
584 if (fd < 0 || adjust_shared_perm(lock_file)) {
585 fprintf(stderr, "could not lock config file\n");
586 free(store.key);
587 ret = -1;
588 goto out_free;
589 }
590
591 /*
592 * If .git/config does not exist yet, write a minimal version.
593 */
594 in_fd = open(config_filename, O_RDONLY);
595 if ( in_fd < 0 ) {
596 free(store.key);
597
598 if ( ENOENT != errno ) {
599 error("opening %s: %s", config_filename,
600 strerror(errno));
601 ret = 3; /* same as "invalid config file" */
602 goto out_free;
603 }
604 /* if nothing to unset, error out */
605 if (value == NULL) {
606 ret = 5;
607 goto out_free;
608 }
609
610 store.key = (char*)key;
611 store_write_section(fd, key);
612 store_write_pair(fd, key, value);
613 } else{
614 struct stat st;
615 char* contents;
616 int i, copy_begin, copy_end, new_line = 0;
617
618 if (value_regex == NULL)
619 store.value_regex = NULL;
620 else {
621 if (value_regex[0] == '!') {
622 store.do_not_match = 1;
623 value_regex++;
624 } else
625 store.do_not_match = 0;
626
627 store.value_regex = (regex_t*)malloc(sizeof(regex_t));
628 if (regcomp(store.value_regex, value_regex,
629 REG_EXTENDED)) {
630 fprintf(stderr, "Invalid pattern: %s\n",
631 value_regex);
632 free(store.value_regex);
633 ret = 6;
634 goto out_free;
635 }
636 }
637
638 store.offset[0] = 0;
639 store.state = START;
640 store.seen = 0;
641
642 /*
643 * After this, store.offset will contain the *end* offset
644 * of the last match, or remain at 0 if no match was found.
645 * As a side effect, we make sure to transform only a valid
646 * existing config file.
647 */
648 if (git_config_from_file(store_aux, config_filename)) {
649 fprintf(stderr, "invalid config file\n");
650 free(store.key);
651 if (store.value_regex != NULL) {
652 regfree(store.value_regex);
653 free(store.value_regex);
654 }
655 ret = 3;
656 goto out_free;
657 }
658
659 free(store.key);
660 if (store.value_regex != NULL) {
661 regfree(store.value_regex);
662 free(store.value_regex);
663 }
664
665 /* if nothing to unset, or too many matches, error out */
666 if ((store.seen == 0 && value == NULL) ||
667 (store.seen > 1 && multi_replace == 0)) {
668 ret = 5;
669 goto out_free;
670 }
671
672 fstat(in_fd, &st);
673 contents = mmap(NULL, st.st_size, PROT_READ,
674 MAP_PRIVATE, in_fd, 0);
675 close(in_fd);
676
677 if (store.seen == 0)
678 store.seen = 1;
679
680 for (i = 0, copy_begin = 0; i < store.seen; i++) {
681 if (store.offset[i] == 0) {
682 store.offset[i] = copy_end = st.st_size;
683 } else if (store.state != KEY_SEEN) {
684 copy_end = store.offset[i];
685 } else
686 copy_end = find_beginning_of_line(
687 contents, st.st_size,
688 store.offset[i]-2, &new_line);
689
690 /* write the first part of the config */
691 if (copy_end > copy_begin) {
692 write(fd, contents + copy_begin,
693 copy_end - copy_begin);
694 if (new_line)
695 write(fd, "\n", 1);
696 }
697 copy_begin = store.offset[i];
698 }
699
700 /* write the pair (value == NULL means unset) */
701 if (value != NULL) {
702 if (store.state == START)
703 store_write_section(fd, key);
704 store_write_pair(fd, key, value);
705 }
706
707 /* write the rest of the config */
708 if (copy_begin < st.st_size)
709 write(fd, contents + copy_begin,
710 st.st_size - copy_begin);
711
712 munmap(contents, st.st_size);
713 unlink(config_filename);
714 }
715
716 if (rename(lock_file, config_filename) < 0) {
717 fprintf(stderr, "Could not rename the lock file?\n");
718 ret = 4;
719 goto out_free;
720 }
721
722 ret = 0;
723
724 out_free:
725 if (0 <= fd)
726 close(fd);
727 if (config_filename)
728 free(config_filename);
729 if (lock_file) {
730 unlink(lock_file);
731 free(lock_file);
732 }
733 return ret;
734 }
735
736