bbcafff29f115d3cb1e42d6eb945a857e6aea447
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>
11 #define MAXNAME (256)
13 static FILE *config_file;
14 static int config_linenr;
15 static int get_next_char(void)
16 {
17 int c;
18 FILE *f;
20 c = '\n';
21 if ((f = config_file) != NULL) {
22 c = fgetc(f);
23 if (c == '\r') {
24 /* DOS like systems */
25 c = fgetc(f);
26 if (c != '\n') {
27 ungetc(c, f);
28 c = '\r';
29 }
30 }
31 if (c == '\n')
32 config_linenr++;
33 if (c == EOF) {
34 config_file = NULL;
35 c = '\n';
36 }
37 }
38 return c;
39 }
41 static char *parse_value(void)
42 {
43 static char value[1024];
44 int quote = 0, comment = 0, len = 0, space = 0;
46 for (;;) {
47 int c = get_next_char();
48 if (len >= sizeof(value))
49 return NULL;
50 if (c == '\n') {
51 if (quote)
52 return NULL;
53 value[len] = 0;
54 return value;
55 }
56 if (comment)
57 continue;
58 if (isspace(c) && !quote) {
59 space = 1;
60 continue;
61 }
62 if (space) {
63 if (len)
64 value[len++] = ' ';
65 space = 0;
66 }
67 if (c == '\\') {
68 c = get_next_char();
69 switch (c) {
70 case '\n':
71 continue;
72 case 't':
73 c = '\t';
74 break;
75 case 'b':
76 c = '\b';
77 break;
78 case 'n':
79 c = '\n';
80 break;
81 /* Some characters escape as themselves */
82 case '\\': case '"':
83 break;
84 /* Reject unknown escape sequences */
85 default:
86 return NULL;
87 }
88 value[len++] = c;
89 continue;
90 }
91 if (c == '"') {
92 quote = 1-quote;
93 continue;
94 }
95 if (!quote) {
96 if (c == ';' || c == '#') {
97 comment = 1;
98 continue;
99 }
100 }
101 value[len++] = c;
102 }
103 }
105 static int get_value(config_fn_t fn, char *name, unsigned int len)
106 {
107 int c;
108 char *value;
110 /* Get the full name */
111 for (;;) {
112 c = get_next_char();
113 if (c == EOF)
114 break;
115 if (!isalnum(c))
116 break;
117 name[len++] = tolower(c);
118 if (len >= MAXNAME)
119 return -1;
120 }
121 name[len] = 0;
122 while (c == ' ' || c == '\t')
123 c = get_next_char();
125 value = NULL;
126 if (c != '\n') {
127 if (c != '=')
128 return -1;
129 value = parse_value();
130 if (!value)
131 return -1;
132 }
133 return fn(name, value);
134 }
136 static int get_base_var(char *name)
137 {
138 int baselen = 0;
140 for (;;) {
141 int c = get_next_char();
142 if (c == EOF)
143 return -1;
144 if (c == ']')
145 return baselen;
146 if (!isalnum(c))
147 return -1;
148 if (baselen > MAXNAME / 2)
149 return -1;
150 name[baselen++] = tolower(c);
151 }
152 }
154 static int git_parse_file(config_fn_t fn)
155 {
156 int comment = 0;
157 int baselen = 0;
158 static char var[MAXNAME];
160 for (;;) {
161 int c = get_next_char();
162 if (c == '\n') {
163 /* EOF? */
164 if (!config_file)
165 return 0;
166 comment = 0;
167 continue;
168 }
169 if (comment || isspace(c))
170 continue;
171 if (c == '#' || c == ';') {
172 comment = 1;
173 continue;
174 }
175 if (c == '[') {
176 baselen = get_base_var(var);
177 if (baselen <= 0)
178 break;
179 var[baselen++] = '.';
180 var[baselen] = 0;
181 continue;
182 }
183 if (!isalpha(c))
184 break;
185 var[baselen] = tolower(c);
186 if (get_value(fn, var, baselen+1) < 0)
187 break;
188 }
189 die("bad config file line %d", config_linenr);
190 }
192 int git_config_int(const char *name, const char *value)
193 {
194 if (value && *value) {
195 char *end;
196 int val = strtol(value, &end, 0);
197 if (!*end)
198 return val;
199 }
200 die("bad config value for '%s'", name);
201 }
203 int git_config_bool(const char *name, const char *value)
204 {
205 if (!value)
206 return 1;
207 if (!*value)
208 return 0;
209 if (!strcasecmp(value, "true"))
210 return 1;
211 if (!strcasecmp(value, "false"))
212 return 0;
213 return git_config_int(name, value) != 0;
214 }
216 int git_default_config(const char *var, const char *value)
217 {
218 /* This needs a better name */
219 if (!strcmp(var, "core.filemode")) {
220 trust_executable_bit = git_config_bool(var, value);
221 return 0;
222 }
224 if (!strcmp(var, "core.symrefsonly")) {
225 only_use_symrefs = git_config_bool(var, value);
226 return 0;
227 }
229 if (!strcmp(var, "user.name")) {
230 strncpy(git_default_name, value, sizeof(git_default_name));
231 return 0;
232 }
234 if (!strcmp(var, "user.email")) {
235 strncpy(git_default_email, value, sizeof(git_default_email));
236 return 0;
237 }
239 if (!strcmp(var, "diff.renamelimit")) {
240 diff_rename_limit_default = git_config_int(var, value);
241 return 0;
242 }
244 /* Add other config variables here.. */
245 return 0;
246 }
248 int git_config(config_fn_t fn)
249 {
250 int ret;
251 FILE *f = fopen(git_path("config"), "r");
253 ret = -1;
254 if (f) {
255 config_file = f;
256 config_linenr = 1;
257 ret = git_parse_file(fn);
258 fclose(f);
259 }
260 return ret;
261 }
263 /*
264 * Find all the stuff for git_config_set() below.
265 */
266 static struct {
267 int baselen;
268 char* key;
269 regex_t* value_regex;
270 off_t offset;
271 enum { START, SECTION_SEEN, SECTION_END_SEEN, KEY_SEEN } state;
272 int seen;
273 } store;
275 static int store_aux(const char* key, const char* value)
276 {
277 switch (store.state) {
278 case KEY_SEEN:
279 if (!strcmp(key, store.key) &&
280 (store.value_regex == NULL ||
281 !regexec(store.value_regex, value, 0, NULL, 0))) {
282 if (store.seen == 1) {
283 fprintf(stderr,
284 "Warning: %s has multiple values\n",
285 key);
286 }
287 store.offset = ftell(config_file);
288 store.seen++;
289 }
290 break;
291 case SECTION_SEEN:
292 if (strncmp(key, store.key, store.baselen+1)) {
293 store.state = SECTION_END_SEEN;
294 break;
295 } else
296 store.offset = ftell(config_file);
297 /* fallthru */
298 case SECTION_END_SEEN:
299 case START:
300 if (!strcmp(key, store.key) &&
301 (store.value_regex == NULL ||
302 !regexec(store.value_regex, value, 0, NULL, 0))) {
303 store.offset = ftell(config_file);
304 store.state = KEY_SEEN;
305 store.seen++;
306 } else if(!strncmp(key, store.key, store.baselen))
307 store.state = SECTION_SEEN;
308 }
309 return 0;
310 }
312 static void store_write_section(int fd, const char* key)
313 {
314 write(fd, "[", 1);
315 write(fd, key, store.baselen);
316 write(fd, "]\n", 2);
317 }
319 static void store_write_pair(int fd, const char* key, const char* value)
320 {
321 int i;
323 write(fd, "\t", 1);
324 write(fd, key+store.baselen+1,
325 strlen(key+store.baselen+1));
326 write(fd, " = ", 3);
327 for (i = 0; value[i]; i++)
328 switch (value[i]) {
329 case '\n': write(fd, "\\n", 2); break;
330 case '\t': write(fd, "\\t", 2); break;
331 case '"': case '\\': write(fd, "\\", 1);
332 default: write(fd, value+i, 1);
333 }
334 write(fd, "\n", 1);
335 }
337 int git_config_set(const char* key, const char* value)
338 {
339 return git_config_set_multivar(key, value, NULL);
340 }
342 /*
343 * If value==NULL, unset in (remove from) config,
344 * if value_regex!=NULL, disregard key/value pairs where value does not match.
345 *
346 * Returns 0 on success.
347 *
348 * This function does this:
349 *
350 * - it locks the config file by creating ".git/config.lock"
351 *
352 * - it then parses the config using store_aux() as validator to find
353 * the position on the key/value pair to replace. If it is to be unset,
354 * it must be found exactly once.
355 *
356 * - the config file is mmap()ed and the part before the match (if any) is
357 * written to the lock file, then the changed part and the rest.
358 *
359 * - the config file is removed and the lock file rename()d to it.
360 *
361 */
362 int git_config_set_multivar(const char* key, const char* value,
363 const char* value_regex)
364 {
365 int i;
366 struct stat st;
367 int fd;
368 char* config_file = strdup(git_path("config"));
369 char* lock_file = strdup(git_path("config.lock"));
371 /*
372 * Since "key" actually contains the section name and the real
373 * key name separated by a dot, we have to know where the dot is.
374 */
375 for (store.baselen = 0;
376 key[store.baselen] != '.' && key[store.baselen];
377 store.baselen++);
378 if (!key[store.baselen] || !key[store.baselen+1]) {
379 fprintf(stderr, "key does not contain a section: %s\n", key);
380 return 2;
381 }
383 /*
384 * Validate the key and while at it, lower case it for matching.
385 */
386 store.key = (char*)malloc(strlen(key)+1);
387 for (i = 0; key[i]; i++)
388 if (i != store.baselen && (!isalnum(key[i]) ||
389 (i == store.baselen+1 && !isalpha(key[i])))) {
390 fprintf(stderr, "invalid key: %s\n", key);
391 free(store.key);
392 return 1;
393 } else
394 store.key[i] = tolower(key[i]);
396 /*
397 * The lock_file serves a purpose in addition to locking: the new
398 * contents of .git/config will be written into it.
399 */
400 fd = open(lock_file, O_WRONLY | O_CREAT | O_EXCL, 0666);
401 if (fd < 0) {
402 fprintf(stderr, "could not lock config file\n");
403 free(store.key);
404 return -1;
405 }
407 /*
408 * If .git/config does not exist yet, write a minimal version.
409 */
410 if (stat(config_file, &st)) {
411 static const char contents[] =
412 "#\n"
413 "# This is the config file\n"
414 "#\n"
415 "\n";
417 free(store.key);
419 /* if nothing to unset, error out */
420 if (value == NULL) {
421 close(fd);
422 unlink(lock_file);
423 return 5;
424 }
426 store.key = (char*)key;
428 write(fd, contents, sizeof(contents)-1);
429 store_write_section(fd, key);
430 store_write_pair(fd, key, value);
431 } else{
432 int in_fd;
433 char* contents;
434 int offset, new_line = 0;
436 if (value_regex == NULL)
437 store.value_regex = NULL;
438 else {
439 store.value_regex = (regex_t*)malloc(sizeof(regex_t));
440 if (regcomp(store.value_regex, value_regex,
441 REG_EXTENDED)) {
442 fprintf(stderr, "Invalid pattern: %s",
443 value_regex);
444 free(store.value_regex);
445 return 6;
446 }
447 }
449 store.offset = 0;
450 store.state = START;
451 store.seen = 0;
453 /*
454 * After this, store.offset will contain the *end* offset
455 * of the last match, or remain at 0 if no match was found.
456 * As a side effect, we make sure to transform only a valid
457 * existing config file.
458 */
459 if (git_config(store_aux)) {
460 fprintf(stderr, "invalid config file\n");
461 free(store.key);
462 if (store.value_regex != NULL) {
463 regfree(store.value_regex);
464 free(store.value_regex);
465 }
466 return 3;
467 }
469 free(store.key);
470 if (store.value_regex != NULL) {
471 regfree(store.value_regex);
472 free(store.value_regex);
473 }
475 /* if nothing to unset, error out */
476 if (store.seen == 0 && value == NULL) {
477 close(fd);
478 unlink(lock_file);
479 return 5;
480 }
482 store.key = (char*)key;
484 in_fd = open(config_file, O_RDONLY, 0666);
485 contents = mmap(NULL, st.st_size, PROT_READ,
486 MAP_PRIVATE, in_fd, 0);
487 close(in_fd);
489 if (store.offset == 0) {
490 store.offset = offset = st.st_size;
491 } else if (store.state != KEY_SEEN) {
492 offset = store.offset;
493 } else {
494 int equal_offset = st.st_size,
495 bracket_offset = st.st_size;
497 if (value == NULL && store.seen > 1) {
498 fprintf(stderr, "Cannot remove multivar (%s has %d values\n", key, store.seen);
499 close(fd);
500 unlink(lock_file);
501 return 7;
502 }
503 for (offset = store.offset-2; offset > 0
504 && contents[offset] != '\n'; offset--)
505 switch (contents[offset]) {
506 case '=': equal_offset = offset; break;
507 case ']': bracket_offset = offset; break;
508 }
509 if (bracket_offset < equal_offset) {
510 new_line = 1;
511 offset = bracket_offset+1;
512 } else
513 offset++;
514 }
516 /* write the first part of the config */
517 write(fd, contents, offset);
518 if (new_line)
519 write(fd, "\n", 1);
521 /* write the pair (value == NULL means unset) */
522 if (value != NULL) {
523 if (store.state == START)
524 store_write_section(fd, key);
525 store_write_pair(fd, key, value);
526 }
528 /* write the rest of the config */
529 if (store.offset < st.st_size)
530 write(fd, contents + store.offset,
531 st.st_size - store.offset);
533 munmap(contents, st.st_size);
534 unlink(config_file);
535 }
537 close(fd);
539 if (rename(lock_file, config_file) < 0) {
540 fprintf(stderr, "Could not rename the lock file?\n");
541 return 4;
542 }
544 return 0;
545 }