34584f62b40ef256d1d0f75e2ee16ed30b1c11fa
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 (space) {
64 if (len)
65 value[len++] = ' ';
66 space = 0;
67 }
68 if (c == '\\') {
69 c = get_next_char();
70 switch (c) {
71 case '\n':
72 continue;
73 case 't':
74 c = '\t';
75 break;
76 case 'b':
77 c = '\b';
78 break;
79 case 'n':
80 c = '\n';
81 break;
82 /* Some characters escape as themselves */
83 case '\\': case '"':
84 break;
85 /* Reject unknown escape sequences */
86 default:
87 return NULL;
88 }
89 value[len++] = c;
90 continue;
91 }
92 if (c == '"') {
93 quote = 1-quote;
94 continue;
95 }
96 if (!quote) {
97 if (c == ';' || c == '#') {
98 comment = 1;
99 continue;
100 }
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_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
155static 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
193int 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
204int 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
217int 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.symrefsonly")) {
226 only_use_symrefs = git_config_bool(var, value);
227 return 0;
228 }
229
230 if (!strcmp(var, "user.name")) {
231 strncpy(git_default_name, value, sizeof(git_default_name));
232 return 0;
233 }
234
235 if (!strcmp(var, "user.email")) {
236 strncpy(git_default_email, value, sizeof(git_default_email));
237 return 0;
238 }
239
240 if (!strcmp(var, "i18n.commitencoding")) {
241 strncpy(git_commit_encoding, value, sizeof(git_commit_encoding));
242 return 0;
243 }
244
245 /* Add other config variables here.. */
246 return 0;
247}
248
249int git_config_from_file(config_fn_t fn, const char *filename)
250{
251 int ret;
252 FILE *f = fopen(filename, "r");
253
254 ret = -1;
255 if (f) {
256 config_file = f;
257 config_file_name = filename;
258 config_linenr = 1;
259 ret = git_parse_file(fn);
260 fclose(f);
261 config_file_name = NULL;
262 }
263 return ret;
264}
265
266int git_config(config_fn_t fn)
267{
268 return git_config_from_file(fn, git_path("config"));
269}
270
271/*
272 * Find all the stuff for git_config_set() below.
273 */
274
275#define MAX_MATCHES 512
276
277static struct {
278 int baselen;
279 char* key;
280 int do_not_match;
281 regex_t* value_regex;
282 int multi_replace;
283 off_t offset[MAX_MATCHES];
284 enum { START, SECTION_SEEN, SECTION_END_SEEN, KEY_SEEN } state;
285 int seen;
286} store;
287
288static int matches(const char* key, const char* value)
289{
290 return !strcmp(key, store.key) &&
291 (store.value_regex == NULL ||
292 (store.do_not_match ^
293 !regexec(store.value_regex, value, 0, NULL, 0)));
294}
295
296static int store_aux(const char* key, const char* value)
297{
298 switch (store.state) {
299 case KEY_SEEN:
300 if (matches(key, value)) {
301 if (store.seen == 1 && store.multi_replace == 0) {
302 fprintf(stderr,
303 "Warning: %s has multiple values\n",
304 key);
305 } else if (store.seen >= MAX_MATCHES) {
306 fprintf(stderr, "Too many matches\n");
307 return 1;
308 }
309
310 store.offset[store.seen] = ftell(config_file);
311 store.seen++;
312 }
313 break;
314 case SECTION_SEEN:
315 if (strncmp(key, store.key, store.baselen+1)) {
316 store.state = SECTION_END_SEEN;
317 break;
318 } else
319 /* do not increment matches: this is no match */
320 store.offset[store.seen] = ftell(config_file);
321 /* fallthru */
322 case SECTION_END_SEEN:
323 case START:
324 if (matches(key, value)) {
325 store.offset[store.seen] = ftell(config_file);
326 store.state = KEY_SEEN;
327 store.seen++;
328 } else if(!strncmp(key, store.key, store.baselen))
329 store.state = SECTION_SEEN;
330 }
331 return 0;
332}
333
334static void store_write_section(int fd, const char* key)
335{
336 write(fd, "[", 1);
337 write(fd, key, store.baselen);
338 write(fd, "]\n", 2);
339}
340
341static void store_write_pair(int fd, const char* key, const char* value)
342{
343 int i;
344
345 write(fd, "\t", 1);
346 write(fd, key+store.baselen+1,
347 strlen(key+store.baselen+1));
348 write(fd, " = ", 3);
349 for (i = 0; value[i]; i++)
350 switch (value[i]) {
351 case '\n': write(fd, "\\n", 2); break;
352 case '\t': write(fd, "\\t", 2); break;
353 case '"': case '\\': write(fd, "\\", 1);
354 default: write(fd, value+i, 1);
355 }
356 write(fd, "\n", 1);
357}
358
359static int find_beginning_of_line(const char* contents, int size,
360 int offset_, int* found_bracket)
361{
362 int equal_offset = size, bracket_offset = size;
363 int offset;
364
365 for (offset = offset_-2; offset > 0
366 && contents[offset] != '\n'; offset--)
367 switch (contents[offset]) {
368 case '=': equal_offset = offset; break;
369 case ']': bracket_offset = offset; break;
370 }
371 if (bracket_offset < equal_offset) {
372 *found_bracket = 1;
373 offset = bracket_offset+1;
374 } else
375 offset++;
376
377 return offset;
378}
379
380int git_config_set(const char* key, const char* value)
381{
382 return git_config_set_multivar(key, value, NULL, 0);
383}
384
385/*
386 * If value==NULL, unset in (remove from) config,
387 * if value_regex!=NULL, disregard key/value pairs where value does not match.
388 * if multi_replace==0, nothing, or only one matching key/value is replaced,
389 * else all matching key/values (regardless how many) are removed,
390 * before the new pair is written.
391 *
392 * Returns 0 on success.
393 *
394 * This function does this:
395 *
396 * - it locks the config file by creating ".git/config.lock"
397 *
398 * - it then parses the config using store_aux() as validator to find
399 * the position on the key/value pair to replace. If it is to be unset,
400 * it must be found exactly once.
401 *
402 * - the config file is mmap()ed and the part before the match (if any) is
403 * written to the lock file, then the changed part and the rest.
404 *
405 * - the config file is removed and the lock file rename()d to it.
406 *
407 */
408int git_config_set_multivar(const char* key, const char* value,
409 const char* value_regex, int multi_replace)
410{
411 int i;
412 struct stat st;
413 int fd;
414 char* config_filename = strdup(git_path("config"));
415 char* lock_file = strdup(git_path("config.lock"));
416 const char* last_dot = strrchr(key, '.');
417
418 /*
419 * Since "key" actually contains the section name and the real
420 * key name separated by a dot, we have to know where the dot is.
421 */
422
423 if (last_dot == NULL) {
424 fprintf(stderr, "key does not contain a section: %s\n", key);
425 return 2;
426 }
427 store.baselen = last_dot - key;
428
429 store.multi_replace = multi_replace;
430
431 /*
432 * Validate the key and while at it, lower case it for matching.
433 */
434 store.key = (char*)malloc(strlen(key)+1);
435 for (i = 0; key[i]; i++)
436 if (i != store.baselen &&
437 ((!isalnum(key[i]) && key[i] != '.') ||
438 (i == store.baselen+1 && !isalpha(key[i])))) {
439 fprintf(stderr, "invalid key: %s\n", key);
440 free(store.key);
441 return 1;
442 } else
443 store.key[i] = tolower(key[i]);
444 store.key[i] = 0;
445
446 /*
447 * The lock_file serves a purpose in addition to locking: the new
448 * contents of .git/config will be written into it.
449 */
450 fd = open(lock_file, O_WRONLY | O_CREAT | O_EXCL, 0666);
451 if (fd < 0) {
452 fprintf(stderr, "could not lock config file\n");
453 free(store.key);
454 return -1;
455 }
456
457 /*
458 * If .git/config does not exist yet, write a minimal version.
459 */
460 if (stat(config_filename, &st)) {
461 static const char contents[] =
462 "#\n"
463 "# This is the config file\n"
464 "#\n"
465 "\n";
466
467 free(store.key);
468
469 /* if nothing to unset, error out */
470 if (value == NULL) {
471 close(fd);
472 unlink(lock_file);
473 return 5;
474 }
475
476 store.key = (char*)key;
477
478 write(fd, contents, sizeof(contents)-1);
479 store_write_section(fd, key);
480 store_write_pair(fd, key, value);
481 } else{
482 int in_fd;
483 char* contents;
484 int i, copy_begin, copy_end, new_line = 0;
485
486 if (value_regex == NULL)
487 store.value_regex = NULL;
488 else {
489 if (value_regex[0] == '!') {
490 store.do_not_match = 1;
491 value_regex++;
492 } else
493 store.do_not_match = 0;
494
495 store.value_regex = (regex_t*)malloc(sizeof(regex_t));
496 if (regcomp(store.value_regex, value_regex,
497 REG_EXTENDED)) {
498 fprintf(stderr, "Invalid pattern: %s",
499 value_regex);
500 free(store.value_regex);
501 return 6;
502 }
503 }
504
505 store.offset[0] = 0;
506 store.state = START;
507 store.seen = 0;
508
509 /*
510 * After this, store.offset will contain the *end* offset
511 * of the last match, or remain at 0 if no match was found.
512 * As a side effect, we make sure to transform only a valid
513 * existing config file.
514 */
515 if (git_config(store_aux)) {
516 fprintf(stderr, "invalid config file\n");
517 free(store.key);
518 if (store.value_regex != NULL) {
519 regfree(store.value_regex);
520 free(store.value_regex);
521 }
522 return 3;
523 }
524
525 free(store.key);
526 if (store.value_regex != NULL) {
527 regfree(store.value_regex);
528 free(store.value_regex);
529 }
530
531 /* if nothing to unset, or too many matches, error out */
532 if ((store.seen == 0 && value == NULL) ||
533 (store.seen > 1 && multi_replace == 0)) {
534 close(fd);
535 unlink(lock_file);
536 return 5;
537 }
538
539 in_fd = open(config_filename, O_RDONLY, 0666);
540 contents = mmap(NULL, st.st_size, PROT_READ,
541 MAP_PRIVATE, in_fd, 0);
542 close(in_fd);
543
544 if (store.seen == 0)
545 store.seen = 1;
546
547 for (i = 0, copy_begin = 0; i < store.seen; i++) {
548 if (store.offset[i] == 0) {
549 store.offset[i] = copy_end = st.st_size;
550 } else if (store.state != KEY_SEEN) {
551 copy_end = store.offset[i];
552 } else
553 copy_end = find_beginning_of_line(
554 contents, st.st_size,
555 store.offset[i]-2, &new_line);
556
557 /* write the first part of the config */
558 if (copy_end > copy_begin) {
559 write(fd, contents + copy_begin,
560 copy_end - copy_begin);
561 if (new_line)
562 write(fd, "\n", 1);
563 }
564 copy_begin = store.offset[i];
565 }
566
567 /* write the pair (value == NULL means unset) */
568 if (value != NULL) {
569 if (store.state == START)
570 store_write_section(fd, key);
571 store_write_pair(fd, key, value);
572 }
573
574 /* write the rest of the config */
575 if (copy_begin < st.st_size)
576 write(fd, contents + copy_begin,
577 st.st_size - copy_begin);
578
579 munmap(contents, st.st_size);
580 unlink(config_filename);
581 }
582
583 close(fd);
584
585 if (rename(lock_file, config_filename) < 0) {
586 fprintf(stderr, "Could not rename the lock file?\n");
587 return 4;
588 }
589
590 return 0;
591}
592
593