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 strncpy(git_default_name, value, sizeof(git_default_name));
284 return 0;
285 }
286 if (!strcmp(var, "user.email")) {
288 strncpy(git_default_email, value, sizeof(git_default_email));
289 return 0;
290 }
291 if (!strcmp(var, "i18n.commitencoding")) {
293 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 return git_config_from_file(fn, git_path("config"));
321}
322/*
324 * Find all the stuff for git_config_set() below.
325 */
326#define MAX_MATCHES 512
328static struct {
330 int baselen;
331 char* key;
332 int do_not_match;
333 regex_t* value_regex;
334 int multi_replace;
335 off_t offset[MAX_MATCHES];
336 enum { START, SECTION_SEEN, SECTION_END_SEEN, KEY_SEEN } state;
337 int seen;
338} store;
339static int matches(const char* key, const char* value)
341{
342 return !strcmp(key, store.key) &&
343 (store.value_regex == NULL ||
344 (store.do_not_match ^
345 !regexec(store.value_regex, value, 0, NULL, 0)));
346}
347static int store_aux(const char* key, const char* value)
349{
350 switch (store.state) {
351 case KEY_SEEN:
352 if (matches(key, value)) {
353 if (store.seen == 1 && store.multi_replace == 0) {
354 fprintf(stderr,
355 "Warning: %s has multiple values\n",
356 key);
357 } else if (store.seen >= MAX_MATCHES) {
358 fprintf(stderr, "Too many matches\n");
359 return 1;
360 }
361 store.offset[store.seen] = ftell(config_file);
363 store.seen++;
364 }
365 break;
366 case SECTION_SEEN:
367 if (strncmp(key, store.key, store.baselen+1)) {
368 store.state = SECTION_END_SEEN;
369 break;
370 } else
371 /* do not increment matches: this is no match */
372 store.offset[store.seen] = ftell(config_file);
373 /* fallthru */
374 case SECTION_END_SEEN:
375 case START:
376 if (matches(key, value)) {
377 store.offset[store.seen] = ftell(config_file);
378 store.state = KEY_SEEN;
379 store.seen++;
380 } else {
381 if (strrchr(key, '.') - key == store.baselen &&
382 !strncmp(key, store.key, store.baselen)) {
383 store.state = SECTION_SEEN;
384 store.offset[store.seen] = ftell(config_file);
385 }
386 }
387 }
388 return 0;
389}
390static void store_write_section(int fd, const char* key)
392{
393 const char *dot = strchr(key, '.');
394 int len1 = store.baselen, len2 = -1;
395 dot = strchr(key, '.');
397 if (dot) {
398 int dotlen = dot - key;
399 if (dotlen < len1) {
400 len2 = len1 - dotlen - 1;
401 len1 = dotlen;
402 }
403 }
404 write(fd, "[", 1);
406 write(fd, key, len1);
407 if (len2 >= 0) {
408 write(fd, " \"", 2);
409 while (--len2 >= 0) {
410 unsigned char c = *++dot;
411 if (c == '"')
412 write(fd, "\\", 1);
413 write(fd, &c, 1);
414 }
415 write(fd, "\"", 1);
416 }
417 write(fd, "]\n", 2);
418}
419static void store_write_pair(int fd, const char* key, const char* value)
421{
422 int i;
423 write(fd, "\t", 1);
425 write(fd, key+store.baselen+1,
426 strlen(key+store.baselen+1));
427 write(fd, " = ", 3);
428 for (i = 0; value[i]; i++)
429 switch (value[i]) {
430 case '\n': write(fd, "\\n", 2); break;
431 case '\t': write(fd, "\\t", 2); break;
432 case '"': case '\\': write(fd, "\\", 1);
433 default: write(fd, value+i, 1);
434 }
435 write(fd, "\n", 1);
436}
437static int find_beginning_of_line(const char* contents, int size,
439 int offset_, int* found_bracket)
440{
441 int equal_offset = size, bracket_offset = size;
442 int offset;
443 for (offset = offset_-2; offset > 0
445 && contents[offset] != '\n'; offset--)
446 switch (contents[offset]) {
447 case '=': equal_offset = offset; break;
448 case ']': bracket_offset = offset; break;
449 }
450 if (bracket_offset < equal_offset) {
451 *found_bracket = 1;
452 offset = bracket_offset+1;
453 } else
454 offset++;
455 return offset;
457}
458int git_config_set(const char* key, const char* value)
460{
461 return git_config_set_multivar(key, value, NULL, 0);
462}
463/*
465 * If value==NULL, unset in (remove from) config,
466 * if value_regex!=NULL, disregard key/value pairs where value does not match.
467 * if multi_replace==0, nothing, or only one matching key/value is replaced,
468 * else all matching key/values (regardless how many) are removed,
469 * before the new pair is written.
470 *
471 * Returns 0 on success.
472 *
473 * This function does this:
474 *
475 * - it locks the config file by creating ".git/config.lock"
476 *
477 * - it then parses the config using store_aux() as validator to find
478 * the position on the key/value pair to replace. If it is to be unset,
479 * it must be found exactly once.
480 *
481 * - the config file is mmap()ed and the part before the match (if any) is
482 * written to the lock file, then the changed part and the rest.
483 *
484 * - the config file is removed and the lock file rename()d to it.
485 *
486 */
487int git_config_set_multivar(const char* key, const char* value,
488 const char* value_regex, int multi_replace)
489{
490 int i, dot;
491 int fd = -1, in_fd;
492 int ret;
493 char* config_filename = strdup(git_path("config"));
494 char* lock_file = strdup(git_path("config.lock"));
495 const char* last_dot = strrchr(key, '.');
496 /*
498 * Since "key" actually contains the section name and the real
499 * key name separated by a dot, we have to know where the dot is.
500 */
501 if (last_dot == NULL) {
503 fprintf(stderr, "key does not contain a section: %s\n", key);
504 ret = 2;
505 goto out_free;
506 }
507 store.baselen = last_dot - key;
508 store.multi_replace = multi_replace;
510 /*
512 * Validate the key and while at it, lower case it for matching.
513 */
514 store.key = (char*)malloc(strlen(key)+1);
515 dot = 0;
516 for (i = 0; key[i]; i++) {
517 unsigned char c = key[i];
518 if (c == '.')
519 dot = 1;
520 /* Leave the extended basename untouched.. */
521 if (!dot || i > store.baselen) {
522 if (!isalnum(c) || (i == store.baselen+1 && !isalpha(c))) {
523 fprintf(stderr, "invalid key: %s\n", key);
524 free(store.key);
525 ret = 1;
526 goto out_free;
527 }
528 c = tolower(c);
529 }
530 store.key[i] = c;
531 }
532 store.key[i] = 0;
533 /*
535 * The lock_file serves a purpose in addition to locking: the new
536 * contents of .git/config will be written into it.
537 */
538 fd = open(lock_file, O_WRONLY | O_CREAT | O_EXCL, 0666);
539 if (fd < 0 || adjust_shared_perm(lock_file)) {
540 fprintf(stderr, "could not lock config file\n");
541 free(store.key);
542 ret = -1;
543 goto out_free;
544 }
545 /*
547 * If .git/config does not exist yet, write a minimal version.
548 */
549 in_fd = open(config_filename, O_RDONLY);
550 if ( in_fd < 0 ) {
551 free(store.key);
552 if ( ENOENT != errno ) {
554 error("opening %s: %s", config_filename,
555 strerror(errno));
556 ret = 3; /* same as "invalid config file" */
557 goto out_free;
558 }
559 /* if nothing to unset, error out */
560 if (value == NULL) {
561 ret = 5;
562 goto out_free;
563 }
564 store.key = (char*)key;
566 store_write_section(fd, key);
567 store_write_pair(fd, key, value);
568 } else{
569 struct stat st;
570 char* contents;
571 int i, copy_begin, copy_end, new_line = 0;
572 if (value_regex == NULL)
574 store.value_regex = NULL;
575 else {
576 if (value_regex[0] == '!') {
577 store.do_not_match = 1;
578 value_regex++;
579 } else
580 store.do_not_match = 0;
581 store.value_regex = (regex_t*)malloc(sizeof(regex_t));
583 if (regcomp(store.value_regex, value_regex,
584 REG_EXTENDED)) {
585 fprintf(stderr, "Invalid pattern: %s\n",
586 value_regex);
587 free(store.value_regex);
588 ret = 6;
589 goto out_free;
590 }
591 }
592 store.offset[0] = 0;
594 store.state = START;
595 store.seen = 0;
596 /*
598 * After this, store.offset will contain the *end* offset
599 * of the last match, or remain at 0 if no match was found.
600 * As a side effect, we make sure to transform only a valid
601 * existing config file.
602 */
603 if (git_config(store_aux)) {
604 fprintf(stderr, "invalid config file\n");
605 free(store.key);
606 if (store.value_regex != NULL) {
607 regfree(store.value_regex);
608 free(store.value_regex);
609 }
610 ret = 3;
611 goto out_free;
612 }
613 free(store.key);
615 if (store.value_regex != NULL) {
616 regfree(store.value_regex);
617 free(store.value_regex);
618 }
619 /* if nothing to unset, or too many matches, error out */
621 if ((store.seen == 0 && value == NULL) ||
622 (store.seen > 1 && multi_replace == 0)) {
623 ret = 5;
624 goto out_free;
625 }
626 fstat(in_fd, &st);
628 contents = mmap(NULL, st.st_size, PROT_READ,
629 MAP_PRIVATE, in_fd, 0);
630 close(in_fd);
631 if (store.seen == 0)
633 store.seen = 1;
634 for (i = 0, copy_begin = 0; i < store.seen; i++) {
636 if (store.offset[i] == 0) {
637 store.offset[i] = copy_end = st.st_size;
638 } else if (store.state != KEY_SEEN) {
639 copy_end = store.offset[i];
640 } else
641 copy_end = find_beginning_of_line(
642 contents, st.st_size,
643 store.offset[i]-2, &new_line);
644 /* write the first part of the config */
646 if (copy_end > copy_begin) {
647 write(fd, contents + copy_begin,
648 copy_end - copy_begin);
649 if (new_line)
650 write(fd, "\n", 1);
651 }
652 copy_begin = store.offset[i];
653 }
654 /* write the pair (value == NULL means unset) */
656 if (value != NULL) {
657 if (store.state == START)
658 store_write_section(fd, key);
659 store_write_pair(fd, key, value);
660 }
661 /* write the rest of the config */
663 if (copy_begin < st.st_size)
664 write(fd, contents + copy_begin,
665 st.st_size - copy_begin);
666 munmap(contents, st.st_size);
668 unlink(config_filename);
669 }
670 if (rename(lock_file, config_filename) < 0) {
672 fprintf(stderr, "Could not rename the lock file?\n");
673 ret = 4;
674 goto out_free;
675 }
676 ret = 0;
678out_free:
680 if (0 <= fd)
681 close(fd);
682 if (config_filename)
683 free(config_filename);
684 if (lock_file) {
685 unlink(lock_file);
686 free(lock_file);
687 }
688 return ret;
689}
690