Introduce new config option for mmap limit.
[alt-git.git] / config.c
blob0c21286cb25d6a0d1f4dca4e82e59dcb7165e0d5
1 /*
2 * GIT - The information manager from hell
4 * Copyright (C) Linus Torvalds, 2005
5 * Copyright (C) Johannes Schindelin, 2005
7 */
8 #include "cache.h"
10 #define MAXNAME (256)
12 static FILE *config_file;
13 static const char *config_file_name;
14 static int config_linenr;
15 static int get_next_char(void)
17 int c;
18 FILE *f;
20 c = '\n';
21 if ((f = config_file) != NULL) {
22 c = fgetc(f);
23 if (c == '\r') {
24 /* DOS like systems */
25 c = fgetc(f);
26 if (c != '\n') {
27 ungetc(c, f);
28 c = '\r';
31 if (c == '\n')
32 config_linenr++;
33 if (c == EOF) {
34 config_file = NULL;
35 c = '\n';
38 return c;
41 static char *parse_value(void)
43 static char value[1024];
44 int quote = 0, comment = 0, len = 0, space = 0;
46 for (;;) {
47 int c = get_next_char();
48 if (len >= sizeof(value))
49 return NULL;
50 if (c == '\n') {
51 if (quote)
52 return NULL;
53 value[len] = 0;
54 return value;
56 if (comment)
57 continue;
58 if (isspace(c) && !quote) {
59 space = 1;
60 continue;
62 if (!quote) {
63 if (c == ';' || c == '#') {
64 comment = 1;
65 continue;
68 if (space) {
69 if (len)
70 value[len++] = ' ';
71 space = 0;
73 if (c == '\\') {
74 c = get_next_char();
75 switch (c) {
76 case '\n':
77 continue;
78 case 't':
79 c = '\t';
80 break;
81 case 'b':
82 c = '\b';
83 break;
84 case 'n':
85 c = '\n';
86 break;
87 /* Some characters escape as themselves */
88 case '\\': case '"':
89 break;
90 /* Reject unknown escape sequences */
91 default:
92 return NULL;
94 value[len++] = c;
95 continue;
97 if (c == '"') {
98 quote = 1-quote;
99 continue;
101 value[len++] = c;
105 static inline int iskeychar(int c)
107 return isalnum(c) || c == '-';
110 static int get_value(config_fn_t fn, char *name, unsigned int len)
112 int c;
113 char *value;
115 /* Get the full name */
116 for (;;) {
117 c = get_next_char();
118 if (c == EOF)
119 break;
120 if (!iskeychar(c))
121 break;
122 name[len++] = tolower(c);
123 if (len >= MAXNAME)
124 return -1;
126 name[len] = 0;
127 while (c == ' ' || c == '\t')
128 c = get_next_char();
130 value = NULL;
131 if (c != '\n') {
132 if (c != '=')
133 return -1;
134 value = parse_value();
135 if (!value)
136 return -1;
138 return fn(name, value);
141 static int get_extended_base_var(char *name, int baselen, int c)
143 do {
144 if (c == '\n')
145 return -1;
146 c = get_next_char();
147 } while (isspace(c));
149 /* We require the format to be '[base "extension"]' */
150 if (c != '"')
151 return -1;
152 name[baselen++] = '.';
154 for (;;) {
155 int c = get_next_char();
156 if (c == '\n')
157 return -1;
158 if (c == '"')
159 break;
160 if (c == '\\') {
161 c = get_next_char();
162 if (c == '\n')
163 return -1;
165 name[baselen++] = c;
166 if (baselen > MAXNAME / 2)
167 return -1;
170 /* Final ']' */
171 if (get_next_char() != ']')
172 return -1;
173 return baselen;
176 static int get_base_var(char *name)
178 int baselen = 0;
180 for (;;) {
181 int c = get_next_char();
182 if (c == EOF)
183 return -1;
184 if (c == ']')
185 return baselen;
186 if (isspace(c))
187 return get_extended_base_var(name, baselen, c);
188 if (!iskeychar(c) && c != '.')
189 return -1;
190 if (baselen > MAXNAME / 2)
191 return -1;
192 name[baselen++] = tolower(c);
196 static int git_parse_file(config_fn_t fn)
198 int comment = 0;
199 int baselen = 0;
200 static char var[MAXNAME];
202 for (;;) {
203 int c = get_next_char();
204 if (c == '\n') {
205 /* EOF? */
206 if (!config_file)
207 return 0;
208 comment = 0;
209 continue;
211 if (comment || isspace(c))
212 continue;
213 if (c == '#' || c == ';') {
214 comment = 1;
215 continue;
217 if (c == '[') {
218 baselen = get_base_var(var);
219 if (baselen <= 0)
220 break;
221 var[baselen++] = '.';
222 var[baselen] = 0;
223 continue;
225 if (!isalpha(c))
226 break;
227 var[baselen] = tolower(c);
228 if (get_value(fn, var, baselen+1) < 0)
229 break;
231 die("bad config file line %d in %s", config_linenr, config_file_name);
234 int git_config_int(const char *name, const char *value)
236 if (value && *value) {
237 char *end;
238 int val = strtol(value, &end, 0);
239 if (!*end)
240 return val;
242 die("bad config value for '%s' in %s", name, config_file_name);
245 int git_config_bool(const char *name, const char *value)
247 if (!value)
248 return 1;
249 if (!*value)
250 return 0;
251 if (!strcasecmp(value, "true") || !strcasecmp(value, "yes"))
252 return 1;
253 if (!strcasecmp(value, "false") || !strcasecmp(value, "no"))
254 return 0;
255 return git_config_int(name, value) != 0;
258 int git_default_config(const char *var, const char *value)
260 /* This needs a better name */
261 if (!strcmp(var, "core.filemode")) {
262 trust_executable_bit = git_config_bool(var, value);
263 return 0;
266 if (!strcmp(var, "core.ignorestat")) {
267 assume_unchanged = git_config_bool(var, value);
268 return 0;
271 if (!strcmp(var, "core.prefersymlinkrefs")) {
272 prefer_symlink_refs = git_config_bool(var, value);
273 return 0;
276 if (!strcmp(var, "core.logallrefupdates")) {
277 log_all_ref_updates = git_config_bool(var, value);
278 return 0;
281 if (!strcmp(var, "core.warnambiguousrefs")) {
282 warn_ambiguous_refs = git_config_bool(var, value);
283 return 0;
286 if (!strcmp(var, "core.legacyheaders")) {
287 use_legacy_headers = git_config_bool(var, value);
288 return 0;
291 if (!strcmp(var, "core.compression")) {
292 int level = git_config_int(var, value);
293 if (level == -1)
294 level = Z_DEFAULT_COMPRESSION;
295 else if (level < 0 || level > Z_BEST_COMPRESSION)
296 die("bad zlib compression level %d", level);
297 zlib_compression_level = level;
298 return 0;
301 if (!strcmp(var, "core.packedgitlimit")) {
302 packed_git_limit = git_config_int(var, value);
303 return 0;
306 if (!strcmp(var, "user.name")) {
307 strlcpy(git_default_name, value, sizeof(git_default_name));
308 return 0;
311 if (!strcmp(var, "user.email")) {
312 strlcpy(git_default_email, value, sizeof(git_default_email));
313 return 0;
316 if (!strcmp(var, "i18n.commitencoding")) {
317 git_commit_encoding = strdup(value);
318 return 0;
321 if (!strcmp(var, "i18n.logoutputencoding")) {
322 git_log_output_encoding = strdup(value);
323 return 0;
327 if (!strcmp(var, "pager.color") || !strcmp(var, "color.pager")) {
328 pager_use_color = git_config_bool(var,value);
329 return 0;
332 /* Add other config variables here and to Documentation/config.txt. */
333 return 0;
336 int git_config_from_file(config_fn_t fn, const char *filename)
338 int ret;
339 FILE *f = fopen(filename, "r");
341 ret = -1;
342 if (f) {
343 config_file = f;
344 config_file_name = filename;
345 config_linenr = 1;
346 ret = git_parse_file(fn);
347 fclose(f);
348 config_file_name = NULL;
350 return ret;
353 int git_config(config_fn_t fn)
355 int ret = 0;
356 char *repo_config = NULL;
357 const char *home = NULL, *filename;
359 /* $GIT_CONFIG makes git read _only_ the given config file,
360 * $GIT_CONFIG_LOCAL will make it process it in addition to the
361 * global config file, the same way it would the per-repository
362 * config file otherwise. */
363 filename = getenv(CONFIG_ENVIRONMENT);
364 if (!filename) {
365 home = getenv("HOME");
366 filename = getenv(CONFIG_LOCAL_ENVIRONMENT);
367 if (!filename)
368 filename = repo_config = xstrdup(git_path("config"));
371 if (home) {
372 char *user_config = xstrdup(mkpath("%s/.gitconfig", home));
373 if (!access(user_config, R_OK))
374 ret = git_config_from_file(fn, user_config);
375 free(user_config);
378 ret += git_config_from_file(fn, filename);
379 free(repo_config);
380 return ret;
384 * Find all the stuff for git_config_set() below.
387 #define MAX_MATCHES 512
389 static struct {
390 int baselen;
391 char* key;
392 int do_not_match;
393 regex_t* value_regex;
394 int multi_replace;
395 off_t offset[MAX_MATCHES];
396 enum { START, SECTION_SEEN, SECTION_END_SEEN, KEY_SEEN } state;
397 int seen;
398 } store;
400 static int matches(const char* key, const char* value)
402 return !strcmp(key, store.key) &&
403 (store.value_regex == NULL ||
404 (store.do_not_match ^
405 !regexec(store.value_regex, value, 0, NULL, 0)));
408 static int store_aux(const char* key, const char* value)
410 switch (store.state) {
411 case KEY_SEEN:
412 if (matches(key, value)) {
413 if (store.seen == 1 && store.multi_replace == 0) {
414 fprintf(stderr,
415 "Warning: %s has multiple values\n",
416 key);
417 } else if (store.seen >= MAX_MATCHES) {
418 fprintf(stderr, "Too many matches\n");
419 return 1;
422 store.offset[store.seen] = ftell(config_file);
423 store.seen++;
425 break;
426 case SECTION_SEEN:
427 if (strncmp(key, store.key, store.baselen+1)) {
428 store.state = SECTION_END_SEEN;
429 break;
430 } else
431 /* do not increment matches: this is no match */
432 store.offset[store.seen] = ftell(config_file);
433 /* fallthru */
434 case SECTION_END_SEEN:
435 case START:
436 if (matches(key, value)) {
437 store.offset[store.seen] = ftell(config_file);
438 store.state = KEY_SEEN;
439 store.seen++;
440 } else {
441 if (strrchr(key, '.') - key == store.baselen &&
442 !strncmp(key, store.key, store.baselen)) {
443 store.state = SECTION_SEEN;
444 store.offset[store.seen] = ftell(config_file);
448 return 0;
451 static void store_write_section(int fd, const char* key)
453 const char *dot = strchr(key, '.');
454 int len1 = store.baselen, len2 = -1;
456 dot = strchr(key, '.');
457 if (dot) {
458 int dotlen = dot - key;
459 if (dotlen < len1) {
460 len2 = len1 - dotlen - 1;
461 len1 = dotlen;
465 write(fd, "[", 1);
466 write(fd, key, len1);
467 if (len2 >= 0) {
468 write(fd, " \"", 2);
469 while (--len2 >= 0) {
470 unsigned char c = *++dot;
471 if (c == '"')
472 write(fd, "\\", 1);
473 write(fd, &c, 1);
475 write(fd, "\"", 1);
477 write(fd, "]\n", 2);
480 static void store_write_pair(int fd, const char* key, const char* value)
482 int i;
484 write(fd, "\t", 1);
485 write(fd, key+store.baselen+1,
486 strlen(key+store.baselen+1));
487 write(fd, " = ", 3);
488 for (i = 0; value[i]; i++)
489 switch (value[i]) {
490 case '\n': write(fd, "\\n", 2); break;
491 case '\t': write(fd, "\\t", 2); break;
492 case '"': case '\\': write(fd, "\\", 1);
493 default: write(fd, value+i, 1);
495 write(fd, "\n", 1);
498 static int find_beginning_of_line(const char* contents, int size,
499 int offset_, int* found_bracket)
501 int equal_offset = size, bracket_offset = size;
502 int offset;
504 for (offset = offset_-2; offset > 0
505 && contents[offset] != '\n'; offset--)
506 switch (contents[offset]) {
507 case '=': equal_offset = offset; break;
508 case ']': bracket_offset = offset; break;
510 if (bracket_offset < equal_offset) {
511 *found_bracket = 1;
512 offset = bracket_offset+1;
513 } else
514 offset++;
516 return offset;
519 int git_config_set(const char* key, const char* value)
521 return git_config_set_multivar(key, value, NULL, 0);
525 * If value==NULL, unset in (remove from) config,
526 * if value_regex!=NULL, disregard key/value pairs where value does not match.
527 * if multi_replace==0, nothing, or only one matching key/value is replaced,
528 * else all matching key/values (regardless how many) are removed,
529 * before the new pair is written.
531 * Returns 0 on success.
533 * This function does this:
535 * - it locks the config file by creating ".git/config.lock"
537 * - it then parses the config using store_aux() as validator to find
538 * the position on the key/value pair to replace. If it is to be unset,
539 * it must be found exactly once.
541 * - the config file is mmap()ed and the part before the match (if any) is
542 * written to the lock file, then the changed part and the rest.
544 * - the config file is removed and the lock file rename()d to it.
547 int git_config_set_multivar(const char* key, const char* value,
548 const char* value_regex, int multi_replace)
550 int i, dot;
551 int fd = -1, in_fd;
552 int ret;
553 char* config_filename;
554 char* lock_file;
555 const char* last_dot = strrchr(key, '.');
557 config_filename = getenv(CONFIG_ENVIRONMENT);
558 if (!config_filename) {
559 config_filename = getenv(CONFIG_LOCAL_ENVIRONMENT);
560 if (!config_filename)
561 config_filename = git_path("config");
563 config_filename = xstrdup(config_filename);
564 lock_file = xstrdup(mkpath("%s.lock", config_filename));
567 * Since "key" actually contains the section name and the real
568 * key name separated by a dot, we have to know where the dot is.
571 if (last_dot == NULL) {
572 fprintf(stderr, "key does not contain a section: %s\n", key);
573 ret = 2;
574 goto out_free;
576 store.baselen = last_dot - key;
578 store.multi_replace = multi_replace;
581 * Validate the key and while at it, lower case it for matching.
583 store.key = xmalloc(strlen(key) + 1);
584 dot = 0;
585 for (i = 0; key[i]; i++) {
586 unsigned char c = key[i];
587 if (c == '.')
588 dot = 1;
589 /* Leave the extended basename untouched.. */
590 if (!dot || i > store.baselen) {
591 if (!iskeychar(c) || (i == store.baselen+1 && !isalpha(c))) {
592 fprintf(stderr, "invalid key: %s\n", key);
593 free(store.key);
594 ret = 1;
595 goto out_free;
597 c = tolower(c);
599 store.key[i] = c;
601 store.key[i] = 0;
604 * The lock_file serves a purpose in addition to locking: the new
605 * contents of .git/config will be written into it.
607 fd = open(lock_file, O_WRONLY | O_CREAT | O_EXCL, 0666);
608 if (fd < 0 || adjust_shared_perm(lock_file)) {
609 fprintf(stderr, "could not lock config file\n");
610 free(store.key);
611 ret = -1;
612 goto out_free;
616 * If .git/config does not exist yet, write a minimal version.
618 in_fd = open(config_filename, O_RDONLY);
619 if ( in_fd < 0 ) {
620 free(store.key);
622 if ( ENOENT != errno ) {
623 error("opening %s: %s", config_filename,
624 strerror(errno));
625 ret = 3; /* same as "invalid config file" */
626 goto out_free;
628 /* if nothing to unset, error out */
629 if (value == NULL) {
630 ret = 5;
631 goto out_free;
634 store.key = (char*)key;
635 store_write_section(fd, key);
636 store_write_pair(fd, key, value);
637 } else{
638 struct stat st;
639 char* contents;
640 int i, copy_begin, copy_end, new_line = 0;
642 if (value_regex == NULL)
643 store.value_regex = NULL;
644 else {
645 if (value_regex[0] == '!') {
646 store.do_not_match = 1;
647 value_regex++;
648 } else
649 store.do_not_match = 0;
651 store.value_regex = (regex_t*)xmalloc(sizeof(regex_t));
652 if (regcomp(store.value_regex, value_regex,
653 REG_EXTENDED)) {
654 fprintf(stderr, "Invalid pattern: %s\n",
655 value_regex);
656 free(store.value_regex);
657 ret = 6;
658 goto out_free;
662 store.offset[0] = 0;
663 store.state = START;
664 store.seen = 0;
667 * After this, store.offset will contain the *end* offset
668 * of the last match, or remain at 0 if no match was found.
669 * As a side effect, we make sure to transform only a valid
670 * existing config file.
672 if (git_config_from_file(store_aux, config_filename)) {
673 fprintf(stderr, "invalid config file\n");
674 free(store.key);
675 if (store.value_regex != NULL) {
676 regfree(store.value_regex);
677 free(store.value_regex);
679 ret = 3;
680 goto out_free;
683 free(store.key);
684 if (store.value_regex != NULL) {
685 regfree(store.value_regex);
686 free(store.value_regex);
689 /* if nothing to unset, or too many matches, error out */
690 if ((store.seen == 0 && value == NULL) ||
691 (store.seen > 1 && multi_replace == 0)) {
692 ret = 5;
693 goto out_free;
696 fstat(in_fd, &st);
697 contents = mmap(NULL, st.st_size, PROT_READ,
698 MAP_PRIVATE, in_fd, 0);
699 close(in_fd);
701 if (store.seen == 0)
702 store.seen = 1;
704 for (i = 0, copy_begin = 0; i < store.seen; i++) {
705 if (store.offset[i] == 0) {
706 store.offset[i] = copy_end = st.st_size;
707 } else if (store.state != KEY_SEEN) {
708 copy_end = store.offset[i];
709 } else
710 copy_end = find_beginning_of_line(
711 contents, st.st_size,
712 store.offset[i]-2, &new_line);
714 /* write the first part of the config */
715 if (copy_end > copy_begin) {
716 write(fd, contents + copy_begin,
717 copy_end - copy_begin);
718 if (new_line)
719 write(fd, "\n", 1);
721 copy_begin = store.offset[i];
724 /* write the pair (value == NULL means unset) */
725 if (value != NULL) {
726 if (store.state == START)
727 store_write_section(fd, key);
728 store_write_pair(fd, key, value);
731 /* write the rest of the config */
732 if (copy_begin < st.st_size)
733 write(fd, contents + copy_begin,
734 st.st_size - copy_begin);
736 munmap(contents, st.st_size);
737 unlink(config_filename);
740 if (rename(lock_file, config_filename) < 0) {
741 fprintf(stderr, "Could not rename the lock file?\n");
742 ret = 4;
743 goto out_free;
746 ret = 0;
748 out_free:
749 if (0 <= fd)
750 close(fd);
751 free(config_filename);
752 if (lock_file) {
753 unlink(lock_file);
754 free(lock_file);
756 return ret;
759 int git_config_rename_section(const char *old_name, const char *new_name)
761 int ret = 0;
762 char *config_filename;
763 struct lock_file *lock = xcalloc(sizeof(struct lock_file), 1);
764 int out_fd;
765 char buf[1024];
767 config_filename = getenv(CONFIG_ENVIRONMENT);
768 if (!config_filename) {
769 config_filename = getenv(CONFIG_LOCAL_ENVIRONMENT);
770 if (!config_filename)
771 config_filename = git_path("config");
773 config_filename = xstrdup(config_filename);
774 out_fd = hold_lock_file_for_update(lock, config_filename, 0);
775 if (out_fd < 0) {
776 ret = error("Could not lock config file!");
777 goto out;
780 if (!(config_file = fopen(config_filename, "rb"))) {
781 ret = error("Could not open config file!");
782 goto out;
785 while (fgets(buf, sizeof(buf), config_file)) {
786 int i;
787 for (i = 0; buf[i] && isspace(buf[i]); i++)
788 ; /* do nothing */
789 if (buf[i] == '[') {
790 /* it's a section */
791 int j = 0, dot = 0;
792 for (i++; buf[i] && buf[i] != ']'; i++) {
793 if (!dot && isspace(buf[i])) {
794 dot = 1;
795 if (old_name[j++] != '.')
796 break;
797 for (i++; isspace(buf[i]); i++)
798 ; /* do nothing */
799 if (buf[i] != '"')
800 break;
801 continue;
803 if (buf[i] == '\\' && dot)
804 i++;
805 else if (buf[i] == '"' && dot) {
806 for (i++; isspace(buf[i]); i++)
807 ; /* do_nothing */
808 break;
810 if (buf[i] != old_name[j++])
811 break;
813 if (buf[i] == ']') {
814 /* old_name matches */
815 ret++;
816 store.baselen = strlen(new_name);
817 store_write_section(out_fd, new_name);
818 continue;
821 write(out_fd, buf, strlen(buf));
823 fclose(config_file);
824 if (close(out_fd) || commit_lock_file(lock) < 0)
825 ret = error("Cannot commit config file!");
826 out:
827 free(config_filename);
828 return ret;