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
13static 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
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
42static 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
106static 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
137static 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
172static 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
192static 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
230int 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
241int 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") || !strcasecmp(value, "yes"))
248 return 1;
249 if (!strcasecmp(value, "false") || !strcasecmp(value, "no"))
250 return 0;
251 return git_config_int(name, value) != 0;
252}
253
254int 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.legacyheaders")) {
283 use_legacy_headers = git_config_bool(var, value);
284 return 0;
285 }
286
287 if (!strcmp(var, "core.compression")) {
288 int level = git_config_int(var, value);
289 if (level == -1)
290 level = Z_DEFAULT_COMPRESSION;
291 else if (level < 0 || level > Z_BEST_COMPRESSION)
292 die("bad zlib compression level %d", level);
293 zlib_compression_level = level;
294 return 0;
295 }
296
297 if (!strcmp(var, "user.name")) {
298 strlcpy(git_default_name, value, sizeof(git_default_name));
299 return 0;
300 }
301
302 if (!strcmp(var, "user.email")) {
303 strlcpy(git_default_email, value, sizeof(git_default_email));
304 return 0;
305 }
306
307 if (!strcmp(var, "i18n.commitencoding")) {
308 strlcpy(git_commit_encoding, value, sizeof(git_commit_encoding));
309 return 0;
310 }
311
312 if (!strcmp(var, "pager.color")) {
313 pager_use_color = git_config_bool(var,value);
314 return 0;
315 }
316
317 /* Add other config variables here and to Documentation/config.txt. */
318 return 0;
319}
320
321int git_config_from_file(config_fn_t fn, const char *filename)
322{
323 int ret;
324 FILE *f = fopen(filename, "r");
325
326 ret = -1;
327 if (f) {
328 config_file = f;
329 config_file_name = filename;
330 config_linenr = 1;
331 ret = git_parse_file(fn);
332 fclose(f);
333 config_file_name = NULL;
334 }
335 return ret;
336}
337
338int git_config(config_fn_t fn)
339{
340 int ret = 0;
341 char *repo_config = NULL;
342 const char *home = NULL, *filename;
343
344 /* $GIT_CONFIG makes git read _only_ the given config file,
345 * $GIT_CONFIG_LOCAL will make it process it in addition to the
346 * global config file, the same way it would the per-repository
347 * config file otherwise. */
348 filename = getenv("GIT_CONFIG");
349 if (!filename) {
350 home = getenv("HOME");
351 filename = getenv("GIT_CONFIG_LOCAL");
352 if (!filename)
353 filename = repo_config = strdup(git_path("config"));
354 }
355
356 if (home) {
357 char *user_config = strdup(mkpath("%s/.gitconfig", home));
358 if (!access(user_config, R_OK))
359 ret = git_config_from_file(fn, user_config);
360 free(user_config);
361 }
362
363 ret += git_config_from_file(fn, filename);
364 if (repo_config)
365 free(repo_config);
366 return ret;
367}
368
369/*
370 * Find all the stuff for git_config_set() below.
371 */
372
373#define MAX_MATCHES 512
374
375static struct {
376 int baselen;
377 char* key;
378 int do_not_match;
379 regex_t* value_regex;
380 int multi_replace;
381 off_t offset[MAX_MATCHES];
382 enum { START, SECTION_SEEN, SECTION_END_SEEN, KEY_SEEN } state;
383 int seen;
384} store;
385
386static int matches(const char* key, const char* value)
387{
388 return !strcmp(key, store.key) &&
389 (store.value_regex == NULL ||
390 (store.do_not_match ^
391 !regexec(store.value_regex, value, 0, NULL, 0)));
392}
393
394static int store_aux(const char* key, const char* value)
395{
396 switch (store.state) {
397 case KEY_SEEN:
398 if (matches(key, value)) {
399 if (store.seen == 1 && store.multi_replace == 0) {
400 fprintf(stderr,
401 "Warning: %s has multiple values\n",
402 key);
403 } else if (store.seen >= MAX_MATCHES) {
404 fprintf(stderr, "Too many matches\n");
405 return 1;
406 }
407
408 store.offset[store.seen] = ftell(config_file);
409 store.seen++;
410 }
411 break;
412 case SECTION_SEEN:
413 if (strncmp(key, store.key, store.baselen+1)) {
414 store.state = SECTION_END_SEEN;
415 break;
416 } else
417 /* do not increment matches: this is no match */
418 store.offset[store.seen] = ftell(config_file);
419 /* fallthru */
420 case SECTION_END_SEEN:
421 case START:
422 if (matches(key, value)) {
423 store.offset[store.seen] = ftell(config_file);
424 store.state = KEY_SEEN;
425 store.seen++;
426 } else {
427 if (strrchr(key, '.') - key == store.baselen &&
428 !strncmp(key, store.key, store.baselen)) {
429 store.state = SECTION_SEEN;
430 store.offset[store.seen] = ftell(config_file);
431 }
432 }
433 }
434 return 0;
435}
436
437static void store_write_section(int fd, const char* key)
438{
439 const char *dot = strchr(key, '.');
440 int len1 = store.baselen, len2 = -1;
441
442 dot = strchr(key, '.');
443 if (dot) {
444 int dotlen = dot - key;
445 if (dotlen < len1) {
446 len2 = len1 - dotlen - 1;
447 len1 = dotlen;
448 }
449 }
450
451 write(fd, "[", 1);
452 write(fd, key, len1);
453 if (len2 >= 0) {
454 write(fd, " \"", 2);
455 while (--len2 >= 0) {
456 unsigned char c = *++dot;
457 if (c == '"')
458 write(fd, "\\", 1);
459 write(fd, &c, 1);
460 }
461 write(fd, "\"", 1);
462 }
463 write(fd, "]\n", 2);
464}
465
466static void store_write_pair(int fd, const char* key, const char* value)
467{
468 int i;
469
470 write(fd, "\t", 1);
471 write(fd, key+store.baselen+1,
472 strlen(key+store.baselen+1));
473 write(fd, " = ", 3);
474 for (i = 0; value[i]; i++)
475 switch (value[i]) {
476 case '\n': write(fd, "\\n", 2); break;
477 case '\t': write(fd, "\\t", 2); break;
478 case '"': case '\\': write(fd, "\\", 1);
479 default: write(fd, value+i, 1);
480 }
481 write(fd, "\n", 1);
482}
483
484static int find_beginning_of_line(const char* contents, int size,
485 int offset_, int* found_bracket)
486{
487 int equal_offset = size, bracket_offset = size;
488 int offset;
489
490 for (offset = offset_-2; offset > 0
491 && contents[offset] != '\n'; offset--)
492 switch (contents[offset]) {
493 case '=': equal_offset = offset; break;
494 case ']': bracket_offset = offset; break;
495 }
496 if (bracket_offset < equal_offset) {
497 *found_bracket = 1;
498 offset = bracket_offset+1;
499 } else
500 offset++;
501
502 return offset;
503}
504
505int git_config_set(const char* key, const char* value)
506{
507 return git_config_set_multivar(key, value, NULL, 0);
508}
509
510/*
511 * If value==NULL, unset in (remove from) config,
512 * if value_regex!=NULL, disregard key/value pairs where value does not match.
513 * if multi_replace==0, nothing, or only one matching key/value is replaced,
514 * else all matching key/values (regardless how many) are removed,
515 * before the new pair is written.
516 *
517 * Returns 0 on success.
518 *
519 * This function does this:
520 *
521 * - it locks the config file by creating ".git/config.lock"
522 *
523 * - it then parses the config using store_aux() as validator to find
524 * the position on the key/value pair to replace. If it is to be unset,
525 * it must be found exactly once.
526 *
527 * - the config file is mmap()ed and the part before the match (if any) is
528 * written to the lock file, then the changed part and the rest.
529 *
530 * - the config file is removed and the lock file rename()d to it.
531 *
532 */
533int git_config_set_multivar(const char* key, const char* value,
534 const char* value_regex, int multi_replace)
535{
536 int i, dot;
537 int fd = -1, in_fd;
538 int ret;
539 char* config_filename;
540 char* lock_file;
541 const char* last_dot = strrchr(key, '.');
542
543 config_filename = getenv("GIT_CONFIG");
544 if (!config_filename) {
545 config_filename = getenv("GIT_CONFIG_LOCAL");
546 if (!config_filename)
547 config_filename = git_path("config");
548 }
549 config_filename = strdup(config_filename);
550 lock_file = strdup(mkpath("%s.lock", config_filename));
551
552 /*
553 * Since "key" actually contains the section name and the real
554 * key name separated by a dot, we have to know where the dot is.
555 */
556
557 if (last_dot == NULL) {
558 fprintf(stderr, "key does not contain a section: %s\n", key);
559 ret = 2;
560 goto out_free;
561 }
562 store.baselen = last_dot - key;
563
564 store.multi_replace = multi_replace;
565
566 /*
567 * Validate the key and while at it, lower case it for matching.
568 */
569 store.key = (char*)malloc(strlen(key)+1);
570 dot = 0;
571 for (i = 0; key[i]; i++) {
572 unsigned char c = key[i];
573 if (c == '.')
574 dot = 1;
575 /* Leave the extended basename untouched.. */
576 if (!dot || i > store.baselen) {
577 if (!isalnum(c) || (i == store.baselen+1 && !isalpha(c))) {
578 fprintf(stderr, "invalid key: %s\n", key);
579 free(store.key);
580 ret = 1;
581 goto out_free;
582 }
583 c = tolower(c);
584 }
585 store.key[i] = c;
586 }
587 store.key[i] = 0;
588
589 /*
590 * The lock_file serves a purpose in addition to locking: the new
591 * contents of .git/config will be written into it.
592 */
593 fd = open(lock_file, O_WRONLY | O_CREAT | O_EXCL, 0666);
594 if (fd < 0 || adjust_shared_perm(lock_file)) {
595 fprintf(stderr, "could not lock config file\n");
596 free(store.key);
597 ret = -1;
598 goto out_free;
599 }
600
601 /*
602 * If .git/config does not exist yet, write a minimal version.
603 */
604 in_fd = open(config_filename, O_RDONLY);
605 if ( in_fd < 0 ) {
606 free(store.key);
607
608 if ( ENOENT != errno ) {
609 error("opening %s: %s", config_filename,
610 strerror(errno));
611 ret = 3; /* same as "invalid config file" */
612 goto out_free;
613 }
614 /* if nothing to unset, error out */
615 if (value == NULL) {
616 ret = 5;
617 goto out_free;
618 }
619
620 store.key = (char*)key;
621 store_write_section(fd, key);
622 store_write_pair(fd, key, value);
623 } else{
624 struct stat st;
625 char* contents;
626 int i, copy_begin, copy_end, new_line = 0;
627
628 if (value_regex == NULL)
629 store.value_regex = NULL;
630 else {
631 if (value_regex[0] == '!') {
632 store.do_not_match = 1;
633 value_regex++;
634 } else
635 store.do_not_match = 0;
636
637 store.value_regex = (regex_t*)malloc(sizeof(regex_t));
638 if (regcomp(store.value_regex, value_regex,
639 REG_EXTENDED)) {
640 fprintf(stderr, "Invalid pattern: %s\n",
641 value_regex);
642 free(store.value_regex);
643 ret = 6;
644 goto out_free;
645 }
646 }
647
648 store.offset[0] = 0;
649 store.state = START;
650 store.seen = 0;
651
652 /*
653 * After this, store.offset will contain the *end* offset
654 * of the last match, or remain at 0 if no match was found.
655 * As a side effect, we make sure to transform only a valid
656 * existing config file.
657 */
658 if (git_config_from_file(store_aux, config_filename)) {
659 fprintf(stderr, "invalid config file\n");
660 free(store.key);
661 if (store.value_regex != NULL) {
662 regfree(store.value_regex);
663 free(store.value_regex);
664 }
665 ret = 3;
666 goto out_free;
667 }
668
669 free(store.key);
670 if (store.value_regex != NULL) {
671 regfree(store.value_regex);
672 free(store.value_regex);
673 }
674
675 /* if nothing to unset, or too many matches, error out */
676 if ((store.seen == 0 && value == NULL) ||
677 (store.seen > 1 && multi_replace == 0)) {
678 ret = 5;
679 goto out_free;
680 }
681
682 fstat(in_fd, &st);
683 contents = mmap(NULL, st.st_size, PROT_READ,
684 MAP_PRIVATE, in_fd, 0);
685 close(in_fd);
686
687 if (store.seen == 0)
688 store.seen = 1;
689
690 for (i = 0, copy_begin = 0; i < store.seen; i++) {
691 if (store.offset[i] == 0) {
692 store.offset[i] = copy_end = st.st_size;
693 } else if (store.state != KEY_SEEN) {
694 copy_end = store.offset[i];
695 } else
696 copy_end = find_beginning_of_line(
697 contents, st.st_size,
698 store.offset[i]-2, &new_line);
699
700 /* write the first part of the config */
701 if (copy_end > copy_begin) {
702 write(fd, contents + copy_begin,
703 copy_end - copy_begin);
704 if (new_line)
705 write(fd, "\n", 1);
706 }
707 copy_begin = store.offset[i];
708 }
709
710 /* write the pair (value == NULL means unset) */
711 if (value != NULL) {
712 if (store.state == START)
713 store_write_section(fd, key);
714 store_write_pair(fd, key, value);
715 }
716
717 /* write the rest of the config */
718 if (copy_begin < st.st_size)
719 write(fd, contents + copy_begin,
720 st.st_size - copy_begin);
721
722 munmap(contents, st.st_size);
723 unlink(config_filename);
724 }
725
726 if (rename(lock_file, config_filename) < 0) {
727 fprintf(stderr, "Could not rename the lock file?\n");
728 ret = 4;
729 goto out_free;
730 }
731
732 ret = 0;
733
734out_free:
735 if (0 <= fd)
736 close(fd);
737 if (config_filename)
738 free(config_filename);
739 if (lock_file) {
740 unlink(lock_file);
741 free(lock_file);
742 }
743 return ret;
744}
745
746