Merge git://git.kernel.org/pub/scm/gitk/gitk
[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_base_var(char *name)
138 {
139 int baselen = 0;
140
141 for (;;) {
142 int c = get_next_char();
143 if (c == EOF)
144 return -1;
145 if (c == ']')
146 return baselen;
147 if (!isalnum(c) && c != '.')
148 return -1;
149 if (baselen > MAXNAME / 2)
150 return -1;
151 name[baselen++] = tolower(c);
152 }
153 }
154
155 static int git_parse_file(config_fn_t fn)
156 {
157 int comment = 0;
158 int baselen = 0;
159 static char var[MAXNAME];
160
161 for (;;) {
162 int c = get_next_char();
163 if (c == '\n') {
164 /* EOF? */
165 if (!config_file)
166 return 0;
167 comment = 0;
168 continue;
169 }
170 if (comment || isspace(c))
171 continue;
172 if (c == '#' || c == ';') {
173 comment = 1;
174 continue;
175 }
176 if (c == '[') {
177 baselen = get_base_var(var);
178 if (baselen <= 0)
179 break;
180 var[baselen++] = '.';
181 var[baselen] = 0;
182 continue;
183 }
184 if (!isalpha(c))
185 break;
186 var[baselen] = tolower(c);
187 if (get_value(fn, var, baselen+1) < 0)
188 break;
189 }
190 die("bad config file line %d in %s", config_linenr, config_file_name);
191 }
192
193 int git_config_int(const char *name, const char *value)
194 {
195 if (value && *value) {
196 char *end;
197 int val = strtol(value, &end, 0);
198 if (!*end)
199 return val;
200 }
201 die("bad config value for '%s' in %s", name, config_file_name);
202 }
203
204 int git_config_bool(const char *name, const char *value)
205 {
206 if (!value)
207 return 1;
208 if (!*value)
209 return 0;
210 if (!strcasecmp(value, "true"))
211 return 1;
212 if (!strcasecmp(value, "false"))
213 return 0;
214 return git_config_int(name, value) != 0;
215 }
216
217 int git_default_config(const char *var, const char *value)
218 {
219 /* This needs a better name */
220 if (!strcmp(var, "core.filemode")) {
221 trust_executable_bit = git_config_bool(var, value);
222 return 0;
223 }
224
225 if (!strcmp(var, "core.ignorestat")) {
226 assume_unchanged = git_config_bool(var, value);
227 return 0;
228 }
229
230 if (!strcmp(var, "core.symrefsonly")) {
231 only_use_symrefs = git_config_bool(var, value);
232 return 0;
233 }
234
235 if (!strcmp(var, "core.warnambiguousrefs")) {
236 warn_ambiguous_refs = git_config_bool(var, value);
237 return 0;
238 }
239
240 if (!strcmp(var, "user.name")) {
241 strncpy(git_default_name, value, sizeof(git_default_name));
242 return 0;
243 }
244
245 if (!strcmp(var, "user.email")) {
246 strncpy(git_default_email, value, sizeof(git_default_email));
247 return 0;
248 }
249
250 if (!strcmp(var, "i18n.commitencoding")) {
251 strncpy(git_commit_encoding, value, sizeof(git_commit_encoding));
252 return 0;
253 }
254
255 /* Add other config variables here and to Documentation/config.txt. */
256 return 0;
257 }
258
259 int git_config_from_file(config_fn_t fn, const char *filename)
260 {
261 int ret;
262 FILE *f = fopen(filename, "r");
263
264 ret = -1;
265 if (f) {
266 config_file = f;
267 config_file_name = filename;
268 config_linenr = 1;
269 ret = git_parse_file(fn);
270 fclose(f);
271 config_file_name = NULL;
272 }
273 return ret;
274 }
275
276 int git_config(config_fn_t fn)
277 {
278 return git_config_from_file(fn, git_path("config"));
279 }
280
281 /*
282 * Find all the stuff for git_config_set() below.
283 */
284
285 #define MAX_MATCHES 512
286
287 static struct {
288 int baselen;
289 char* key;
290 int do_not_match;
291 regex_t* value_regex;
292 int multi_replace;
293 off_t offset[MAX_MATCHES];
294 enum { START, SECTION_SEEN, SECTION_END_SEEN, KEY_SEEN } state;
295 int seen;
296 } store;
297
298 static int matches(const char* key, const char* value)
299 {
300 return !strcmp(key, store.key) &&
301 (store.value_regex == NULL ||
302 (store.do_not_match ^
303 !regexec(store.value_regex, value, 0, NULL, 0)));
304 }
305
306 static int store_aux(const char* key, const char* value)
307 {
308 switch (store.state) {
309 case KEY_SEEN:
310 if (matches(key, value)) {
311 if (store.seen == 1 && store.multi_replace == 0) {
312 fprintf(stderr,
313 "Warning: %s has multiple values\n",
314 key);
315 } else if (store.seen >= MAX_MATCHES) {
316 fprintf(stderr, "Too many matches\n");
317 return 1;
318 }
319
320 store.offset[store.seen] = ftell(config_file);
321 store.seen++;
322 }
323 break;
324 case SECTION_SEEN:
325 if (strncmp(key, store.key, store.baselen+1)) {
326 store.state = SECTION_END_SEEN;
327 break;
328 } else
329 /* do not increment matches: this is no match */
330 store.offset[store.seen] = ftell(config_file);
331 /* fallthru */
332 case SECTION_END_SEEN:
333 case START:
334 if (matches(key, value)) {
335 store.offset[store.seen] = ftell(config_file);
336 store.state = KEY_SEEN;
337 store.seen++;
338 } else if(!strncmp(key, store.key, store.baselen))
339 store.state = SECTION_SEEN;
340 }
341 return 0;
342 }
343
344 static void store_write_section(int fd, const char* key)
345 {
346 write(fd, "[", 1);
347 write(fd, key, store.baselen);
348 write(fd, "]\n", 2);
349 }
350
351 static void store_write_pair(int fd, const char* key, const char* value)
352 {
353 int i;
354
355 write(fd, "\t", 1);
356 write(fd, key+store.baselen+1,
357 strlen(key+store.baselen+1));
358 write(fd, " = ", 3);
359 for (i = 0; value[i]; i++)
360 switch (value[i]) {
361 case '\n': write(fd, "\\n", 2); break;
362 case '\t': write(fd, "\\t", 2); break;
363 case '"': case '\\': write(fd, "\\", 1);
364 default: write(fd, value+i, 1);
365 }
366 write(fd, "\n", 1);
367 }
368
369 static int find_beginning_of_line(const char* contents, int size,
370 int offset_, int* found_bracket)
371 {
372 int equal_offset = size, bracket_offset = size;
373 int offset;
374
375 for (offset = offset_-2; offset > 0
376 && contents[offset] != '\n'; offset--)
377 switch (contents[offset]) {
378 case '=': equal_offset = offset; break;
379 case ']': bracket_offset = offset; break;
380 }
381 if (bracket_offset < equal_offset) {
382 *found_bracket = 1;
383 offset = bracket_offset+1;
384 } else
385 offset++;
386
387 return offset;
388 }
389
390 int git_config_set(const char* key, const char* value)
391 {
392 return git_config_set_multivar(key, value, NULL, 0);
393 }
394
395 /*
396 * If value==NULL, unset in (remove from) config,
397 * if value_regex!=NULL, disregard key/value pairs where value does not match.
398 * if multi_replace==0, nothing, or only one matching key/value is replaced,
399 * else all matching key/values (regardless how many) are removed,
400 * before the new pair is written.
401 *
402 * Returns 0 on success.
403 *
404 * This function does this:
405 *
406 * - it locks the config file by creating ".git/config.lock"
407 *
408 * - it then parses the config using store_aux() as validator to find
409 * the position on the key/value pair to replace. If it is to be unset,
410 * it must be found exactly once.
411 *
412 * - the config file is mmap()ed and the part before the match (if any) is
413 * written to the lock file, then the changed part and the rest.
414 *
415 * - the config file is removed and the lock file rename()d to it.
416 *
417 */
418 int git_config_set_multivar(const char* key, const char* value,
419 const char* value_regex, int multi_replace)
420 {
421 int i;
422 int fd, in_fd;
423 int ret;
424 char* config_filename = strdup(git_path("config"));
425 char* lock_file = strdup(git_path("config.lock"));
426 const char* last_dot = strrchr(key, '.');
427
428 /*
429 * Since "key" actually contains the section name and the real
430 * key name separated by a dot, we have to know where the dot is.
431 */
432
433 if (last_dot == NULL) {
434 fprintf(stderr, "key does not contain a section: %s\n", key);
435 ret = 2;
436 goto out_free;
437 }
438 store.baselen = last_dot - key;
439
440 store.multi_replace = multi_replace;
441
442 /*
443 * Validate the key and while at it, lower case it for matching.
444 */
445 store.key = (char*)malloc(strlen(key)+1);
446 for (i = 0; key[i]; i++)
447 if (i != store.baselen &&
448 ((!isalnum(key[i]) && key[i] != '.') ||
449 (i == store.baselen+1 && !isalpha(key[i])))) {
450 fprintf(stderr, "invalid key: %s\n", key);
451 free(store.key);
452 ret = 1;
453 goto out_free;
454 } else
455 store.key[i] = tolower(key[i]);
456 store.key[i] = 0;
457
458 /*
459 * The lock_file serves a purpose in addition to locking: the new
460 * contents of .git/config will be written into it.
461 */
462 fd = open(lock_file, O_WRONLY | O_CREAT | O_EXCL, 0666);
463 if (fd < 0) {
464 fprintf(stderr, "could not lock config file\n");
465 free(store.key);
466 ret = -1;
467 goto out_free;
468 }
469
470 /*
471 * If .git/config does not exist yet, write a minimal version.
472 */
473 in_fd = open(config_filename, O_RDONLY);
474 if ( in_fd < 0 ) {
475 free(store.key);
476
477 if ( ENOENT != errno ) {
478 error("opening %s: %s", config_filename,
479 strerror(errno));
480 close(fd);
481 unlink(lock_file);
482 ret = 3; /* same as "invalid config file" */
483 goto out_free;
484 }
485 /* if nothing to unset, error out */
486 if (value == NULL) {
487 close(fd);
488 unlink(lock_file);
489 ret = 5;
490 goto out_free;
491 }
492
493 store.key = (char*)key;
494 store_write_section(fd, key);
495 store_write_pair(fd, key, value);
496 } else{
497 struct stat st;
498 char* contents;
499 int i, copy_begin, copy_end, new_line = 0;
500
501 if (value_regex == NULL)
502 store.value_regex = NULL;
503 else {
504 if (value_regex[0] == '!') {
505 store.do_not_match = 1;
506 value_regex++;
507 } else
508 store.do_not_match = 0;
509
510 store.value_regex = (regex_t*)malloc(sizeof(regex_t));
511 if (regcomp(store.value_regex, value_regex,
512 REG_EXTENDED)) {
513 fprintf(stderr, "Invalid pattern: %s\n",
514 value_regex);
515 free(store.value_regex);
516 ret = 6;
517 goto out_free;
518 }
519 }
520
521 store.offset[0] = 0;
522 store.state = START;
523 store.seen = 0;
524
525 /*
526 * After this, store.offset will contain the *end* offset
527 * of the last match, or remain at 0 if no match was found.
528 * As a side effect, we make sure to transform only a valid
529 * existing config file.
530 */
531 if (git_config(store_aux)) {
532 fprintf(stderr, "invalid config file\n");
533 free(store.key);
534 if (store.value_regex != NULL) {
535 regfree(store.value_regex);
536 free(store.value_regex);
537 }
538 ret = 3;
539 goto out_free;
540 }
541
542 free(store.key);
543 if (store.value_regex != NULL) {
544 regfree(store.value_regex);
545 free(store.value_regex);
546 }
547
548 /* if nothing to unset, or too many matches, error out */
549 if ((store.seen == 0 && value == NULL) ||
550 (store.seen > 1 && multi_replace == 0)) {
551 close(fd);
552 unlink(lock_file);
553 ret = 5;
554 goto out_free;
555 }
556
557 fstat(in_fd, &st);
558 contents = mmap(NULL, st.st_size, PROT_READ,
559 MAP_PRIVATE, in_fd, 0);
560 close(in_fd);
561
562 if (store.seen == 0)
563 store.seen = 1;
564
565 for (i = 0, copy_begin = 0; i < store.seen; i++) {
566 if (store.offset[i] == 0) {
567 store.offset[i] = copy_end = st.st_size;
568 } else if (store.state != KEY_SEEN) {
569 copy_end = store.offset[i];
570 } else
571 copy_end = find_beginning_of_line(
572 contents, st.st_size,
573 store.offset[i]-2, &new_line);
574
575 /* write the first part of the config */
576 if (copy_end > copy_begin) {
577 write(fd, contents + copy_begin,
578 copy_end - copy_begin);
579 if (new_line)
580 write(fd, "\n", 1);
581 }
582 copy_begin = store.offset[i];
583 }
584
585 /* write the pair (value == NULL means unset) */
586 if (value != NULL) {
587 if (store.state == START)
588 store_write_section(fd, key);
589 store_write_pair(fd, key, value);
590 }
591
592 /* write the rest of the config */
593 if (copy_begin < st.st_size)
594 write(fd, contents + copy_begin,
595 st.st_size - copy_begin);
596
597 munmap(contents, st.st_size);
598 unlink(config_filename);
599 }
600
601 close(fd);
602
603 if (rename(lock_file, config_filename) < 0) {
604 fprintf(stderr, "Could not rename the lock file?\n");
605 ret = 4;
606 goto out_free;
607 }
608
609 ret = 0;
610
611 out_free:
612 if (config_filename)
613 free(config_filename);
614 if (lock_file)
615 free(lock_file);
616 return ret;
617 }
618
619