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#define MAXNAME (256)
12static FILE *config_file;
14static const char *config_file_name;
15static int config_linenr;
16static int get_next_char(void)
17{
18 int c;
19 FILE *f;
20 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}
41static char *parse_value(void)
43{
44 static char value[1024];
45 int quote = 0, comment = 0, len = 0, space = 0;
46 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}
105static int get_value(config_fn_t fn, char *name, unsigned int len)
107{
108 int c;
109 char *value;
110 /* 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 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}
136static 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 /* We require the format to be '[base "extension"]' */
146 if (c != '"')
147 return -1;
148 name[baselen++] = '.';
149 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 /* Final ']' */
167 if (get_next_char() != ']')
168 return -1;
169 return baselen;
170}
171static int get_base_var(char *name)
173{
174 int baselen = 0;
175 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}
191static int git_parse_file(config_fn_t fn)
193{
194 int comment = 0;
195 int baselen = 0;
196 static char var[MAXNAME];
197 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}
229int 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}
240int 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}
253int 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 if (!strcmp(var, "core.ignorestat")) {
263 assume_unchanged = git_config_bool(var, value);
264 return 0;
265 }
266 if (!strcmp(var, "core.prefersymlinkrefs")) {
268 prefer_symlink_refs = git_config_bool(var, value);
269 return 0;
270 }
271 if (!strcmp(var, "core.logallrefupdates")) {
273 log_all_ref_updates = git_config_bool(var, value);
274 return 0;
275 }
276 if (!strcmp(var, "core.warnambiguousrefs")) {
278 warn_ambiguous_refs = git_config_bool(var, value);
279 return 0;
280 }
281 if (!strcmp(var, "user.name")) {
283 safe_strncpy(git_default_name, value, sizeof(git_default_name));
284 return 0;
285 }
286 if (!strcmp(var, "user.email")) {
288 safe_strncpy(git_default_email, value, sizeof(git_default_email));
289 return 0;
290 }
291 if (!strcmp(var, "i18n.commitencoding")) {
293 safe_strncpy(git_commit_encoding, value, sizeof(git_commit_encoding));
294 return 0;
295 }
296 /* Add other config variables here and to Documentation/config.txt. */
298 return 0;
299}
300int git_config_from_file(config_fn_t fn, const char *filename)
302{
303 int ret;
304 FILE *f = fopen(filename, "r");
305 ret = -1;
307 if (f) {
308 config_file = f;
309 config_file_name = filename;
310 config_linenr = 1;
311 ret = git_parse_file(fn);
312 fclose(f);
313 config_file_name = NULL;
314 }
315 return ret;
316}
317int git_config(config_fn_t fn)
319{
320 const char *filename = git_path("config");
321 /* Forward-compatibility cue: $GIT_CONFIG makes git read _only_
322 * the given config file, $GIT_CONFIG_LOCAL will make it process
323 * it in addition to the global config file, the same way it would
324 * the per-repository config file otherwise. */
325 if (getenv("GIT_CONFIG")) {
326 filename = getenv("GIT_CONFIG");
327 } else if (getenv("GIT_CONFIG_LOCAL")) {
328 filename = getenv("GIT_CONFIG_LOCAL");
329 }
330 return git_config_from_file(fn, filename);
331}
332/*
334 * Find all the stuff for git_config_set() below.
335 */
336#define MAX_MATCHES 512
338static struct {
340 int baselen;
341 char* key;
342 int do_not_match;
343 regex_t* value_regex;
344 int multi_replace;
345 off_t offset[MAX_MATCHES];
346 enum { START, SECTION_SEEN, SECTION_END_SEEN, KEY_SEEN } state;
347 int seen;
348} store;
349static int matches(const char* key, const char* value)
351{
352 return !strcmp(key, store.key) &&
353 (store.value_regex == NULL ||
354 (store.do_not_match ^
355 !regexec(store.value_regex, value, 0, NULL, 0)));
356}
357static int store_aux(const char* key, const char* value)
359{
360 switch (store.state) {
361 case KEY_SEEN:
362 if (matches(key, value)) {
363 if (store.seen == 1 && store.multi_replace == 0) {
364 fprintf(stderr,
365 "Warning: %s has multiple values\n",
366 key);
367 } else if (store.seen >= MAX_MATCHES) {
368 fprintf(stderr, "Too many matches\n");
369 return 1;
370 }
371 store.offset[store.seen] = ftell(config_file);
373 store.seen++;
374 }
375 break;
376 case SECTION_SEEN:
377 if (strncmp(key, store.key, store.baselen+1)) {
378 store.state = SECTION_END_SEEN;
379 break;
380 } else
381 /* do not increment matches: this is no match */
382 store.offset[store.seen] = ftell(config_file);
383 /* fallthru */
384 case SECTION_END_SEEN:
385 case START:
386 if (matches(key, value)) {
387 store.offset[store.seen] = ftell(config_file);
388 store.state = KEY_SEEN;
389 store.seen++;
390 } else {
391 if (strrchr(key, '.') - key == store.baselen &&
392 !strncmp(key, store.key, store.baselen)) {
393 store.state = SECTION_SEEN;
394 store.offset[store.seen] = ftell(config_file);
395 }
396 }
397 }
398 return 0;
399}
400static void store_write_section(int fd, const char* key)
402{
403 const char *dot = strchr(key, '.');
404 int len1 = store.baselen, len2 = -1;
405 dot = strchr(key, '.');
407 if (dot) {
408 int dotlen = dot - key;
409 if (dotlen < len1) {
410 len2 = len1 - dotlen - 1;
411 len1 = dotlen;
412 }
413 }
414 write(fd, "[", 1);
416 write(fd, key, len1);
417 if (len2 >= 0) {
418 write(fd, " \"", 2);
419 while (--len2 >= 0) {
420 unsigned char c = *++dot;
421 if (c == '"')
422 write(fd, "\\", 1);
423 write(fd, &c, 1);
424 }
425 write(fd, "\"", 1);
426 }
427 write(fd, "]\n", 2);
428}
429static void store_write_pair(int fd, const char* key, const char* value)
431{
432 int i;
433 write(fd, "\t", 1);
435 write(fd, key+store.baselen+1,
436 strlen(key+store.baselen+1));
437 write(fd, " = ", 3);
438 for (i = 0; value[i]; i++)
439 switch (value[i]) {
440 case '\n': write(fd, "\\n", 2); break;
441 case '\t': write(fd, "\\t", 2); break;
442 case '"': case '\\': write(fd, "\\", 1);
443 default: write(fd, value+i, 1);
444 }
445 write(fd, "\n", 1);
446}
447static int find_beginning_of_line(const char* contents, int size,
449 int offset_, int* found_bracket)
450{
451 int equal_offset = size, bracket_offset = size;
452 int offset;
453 for (offset = offset_-2; offset > 0
455 && contents[offset] != '\n'; offset--)
456 switch (contents[offset]) {
457 case '=': equal_offset = offset; break;
458 case ']': bracket_offset = offset; break;
459 }
460 if (bracket_offset < equal_offset) {
461 *found_bracket = 1;
462 offset = bracket_offset+1;
463 } else
464 offset++;
465 return offset;
467}
468int git_config_set(const char* key, const char* value)
470{
471 return git_config_set_multivar(key, value, NULL, 0);
472}
473/*
475 * If value==NULL, unset in (remove from) config,
476 * if value_regex!=NULL, disregard key/value pairs where value does not match.
477 * if multi_replace==0, nothing, or only one matching key/value is replaced,
478 * else all matching key/values (regardless how many) are removed,
479 * before the new pair is written.
480 *
481 * Returns 0 on success.
482 *
483 * This function does this:
484 *
485 * - it locks the config file by creating ".git/config.lock"
486 *
487 * - it then parses the config using store_aux() as validator to find
488 * the position on the key/value pair to replace. If it is to be unset,
489 * it must be found exactly once.
490 *
491 * - the config file is mmap()ed and the part before the match (if any) is
492 * written to the lock file, then the changed part and the rest.
493 *
494 * - the config file is removed and the lock file rename()d to it.
495 *
496 */
497int git_config_set_multivar(const char* key, const char* value,
498 const char* value_regex, int multi_replace)
499{
500 int i, dot;
501 int fd = -1, in_fd;
502 int ret;
503 char* config_filename;
504 char* lock_file;
505 const char* last_dot = strrchr(key, '.');
506 config_filename = getenv("GIT_CONFIG");
508 if (!config_filename) {
509 config_filename = getenv("GIT_CONFIG_LOCAL");
510 if (!config_filename)
511 config_filename = git_path("config");
512 }
513 config_filename = strdup(config_filename);
514 lock_file = strdup(mkpath("%s.lock", config_filename));
515 /*
517 * Since "key" actually contains the section name and the real
518 * key name separated by a dot, we have to know where the dot is.
519 */
520 if (last_dot == NULL) {
522 fprintf(stderr, "key does not contain a section: %s\n", key);
523 ret = 2;
524 goto out_free;
525 }
526 store.baselen = last_dot - key;
527 store.multi_replace = multi_replace;
529 /*
531 * Validate the key and while at it, lower case it for matching.
532 */
533 store.key = (char*)malloc(strlen(key)+1);
534 dot = 0;
535 for (i = 0; key[i]; i++) {
536 unsigned char c = key[i];
537 if (c == '.')
538 dot = 1;
539 /* Leave the extended basename untouched.. */
540 if (!dot || i > store.baselen) {
541 if (!isalnum(c) || (i == store.baselen+1 && !isalpha(c))) {
542 fprintf(stderr, "invalid key: %s\n", key);
543 free(store.key);
544 ret = 1;
545 goto out_free;
546 }
547 c = tolower(c);
548 }
549 store.key[i] = c;
550 }
551 store.key[i] = 0;
552 /*
554 * The lock_file serves a purpose in addition to locking: the new
555 * contents of .git/config will be written into it.
556 */
557 fd = open(lock_file, O_WRONLY | O_CREAT | O_EXCL, 0666);
558 if (fd < 0 || adjust_shared_perm(lock_file)) {
559 fprintf(stderr, "could not lock config file\n");
560 free(store.key);
561 ret = -1;
562 goto out_free;
563 }
564 /*
566 * If .git/config does not exist yet, write a minimal version.
567 */
568 in_fd = open(config_filename, O_RDONLY);
569 if ( in_fd < 0 ) {
570 free(store.key);
571 if ( ENOENT != errno ) {
573 error("opening %s: %s", config_filename,
574 strerror(errno));
575 ret = 3; /* same as "invalid config file" */
576 goto out_free;
577 }
578 /* if nothing to unset, error out */
579 if (value == NULL) {
580 ret = 5;
581 goto out_free;
582 }
583 store.key = (char*)key;
585 store_write_section(fd, key);
586 store_write_pair(fd, key, value);
587 } else{
588 struct stat st;
589 char* contents;
590 int i, copy_begin, copy_end, new_line = 0;
591 if (value_regex == NULL)
593 store.value_regex = NULL;
594 else {
595 if (value_regex[0] == '!') {
596 store.do_not_match = 1;
597 value_regex++;
598 } else
599 store.do_not_match = 0;
600 store.value_regex = (regex_t*)malloc(sizeof(regex_t));
602 if (regcomp(store.value_regex, value_regex,
603 REG_EXTENDED)) {
604 fprintf(stderr, "Invalid pattern: %s\n",
605 value_regex);
606 free(store.value_regex);
607 ret = 6;
608 goto out_free;
609 }
610 }
611 store.offset[0] = 0;
613 store.state = START;
614 store.seen = 0;
615 /*
617 * After this, store.offset will contain the *end* offset
618 * of the last match, or remain at 0 if no match was found.
619 * As a side effect, we make sure to transform only a valid
620 * existing config file.
621 */
622 if (git_config_from_file(store_aux, config_filename)) {
623 fprintf(stderr, "invalid config file\n");
624 free(store.key);
625 if (store.value_regex != NULL) {
626 regfree(store.value_regex);
627 free(store.value_regex);
628 }
629 ret = 3;
630 goto out_free;
631 }
632 free(store.key);
634 if (store.value_regex != NULL) {
635 regfree(store.value_regex);
636 free(store.value_regex);
637 }
638 /* if nothing to unset, or too many matches, error out */
640 if ((store.seen == 0 && value == NULL) ||
641 (store.seen > 1 && multi_replace == 0)) {
642 ret = 5;
643 goto out_free;
644 }
645 fstat(in_fd, &st);
647 contents = mmap(NULL, st.st_size, PROT_READ,
648 MAP_PRIVATE, in_fd, 0);
649 close(in_fd);
650 if (store.seen == 0)
652 store.seen = 1;
653 for (i = 0, copy_begin = 0; i < store.seen; i++) {
655 if (store.offset[i] == 0) {
656 store.offset[i] = copy_end = st.st_size;
657 } else if (store.state != KEY_SEEN) {
658 copy_end = store.offset[i];
659 } else
660 copy_end = find_beginning_of_line(
661 contents, st.st_size,
662 store.offset[i]-2, &new_line);
663 /* write the first part of the config */
665 if (copy_end > copy_begin) {
666 write(fd, contents + copy_begin,
667 copy_end - copy_begin);
668 if (new_line)
669 write(fd, "\n", 1);
670 }
671 copy_begin = store.offset[i];
672 }
673 /* write the pair (value == NULL means unset) */
675 if (value != NULL) {
676 if (store.state == START)
677 store_write_section(fd, key);
678 store_write_pair(fd, key, value);
679 }
680 /* write the rest of the config */
682 if (copy_begin < st.st_size)
683 write(fd, contents + copy_begin,
684 st.st_size - copy_begin);
685 munmap(contents, st.st_size);
687 unlink(config_filename);
688 }
689 if (rename(lock_file, config_filename) < 0) {
691 fprintf(stderr, "Could not rename the lock file?\n");
692 ret = 4;
693 goto out_free;
694 }
695 ret = 0;
697out_free:
699 if (0 <= fd)
700 close(fd);
701 if (config_filename)
702 free(config_filename);
703 if (lock_file) {
704 unlink(lock_file);
705 free(lock_file);
706 }
707 return ret;
708}
709