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 (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}
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_base_var(char *name)
138{
139 int baselen = 0;
140 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}
154static int git_parse_file(config_fn_t fn)
156{
157 int comment = 0;
158 int baselen = 0;
159 static char var[MAXNAME];
160 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}
192int 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}
203int 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}
216int 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 if (!strcmp(var, "core.ignorestat")) {
226 assume_unchanged = git_config_bool(var, value);
227 return 0;
228 }
229 if (!strcmp(var, "core.symrefsonly")) {
231 only_use_symrefs = git_config_bool(var, value);
232 return 0;
233 }
234 if (!strcmp(var, "user.name")) {
236 strncpy(git_default_name, value, sizeof(git_default_name));
237 return 0;
238 }
239 if (!strcmp(var, "user.email")) {
241 strncpy(git_default_email, value, sizeof(git_default_email));
242 return 0;
243 }
244 if (!strcmp(var, "i18n.commitencoding")) {
246 strncpy(git_commit_encoding, value, sizeof(git_commit_encoding));
247 return 0;
248 }
249 /* Add other config variables here.. */
251 return 0;
252}
253int git_config_from_file(config_fn_t fn, const char *filename)
255{
256 int ret;
257 FILE *f = fopen(filename, "r");
258 ret = -1;
260 if (f) {
261 config_file = f;
262 config_file_name = filename;
263 config_linenr = 1;
264 ret = git_parse_file(fn);
265 fclose(f);
266 config_file_name = NULL;
267 }
268 return ret;
269}
270int git_config(config_fn_t fn)
272{
273 return git_config_from_file(fn, git_path("config"));
274}
275/*
277 * Find all the stuff for git_config_set() below.
278 */
279#define MAX_MATCHES 512
281static struct {
283 int baselen;
284 char* key;
285 int do_not_match;
286 regex_t* value_regex;
287 int multi_replace;
288 off_t offset[MAX_MATCHES];
289 enum { START, SECTION_SEEN, SECTION_END_SEEN, KEY_SEEN } state;
290 int seen;
291} store;
292static int matches(const char* key, const char* value)
294{
295 return !strcmp(key, store.key) &&
296 (store.value_regex == NULL ||
297 (store.do_not_match ^
298 !regexec(store.value_regex, value, 0, NULL, 0)));
299}
300static int store_aux(const char* key, const char* value)
302{
303 switch (store.state) {
304 case KEY_SEEN:
305 if (matches(key, value)) {
306 if (store.seen == 1 && store.multi_replace == 0) {
307 fprintf(stderr,
308 "Warning: %s has multiple values\n",
309 key);
310 } else if (store.seen >= MAX_MATCHES) {
311 fprintf(stderr, "Too many matches\n");
312 return 1;
313 }
314 store.offset[store.seen] = ftell(config_file);
316 store.seen++;
317 }
318 break;
319 case SECTION_SEEN:
320 if (strncmp(key, store.key, store.baselen+1)) {
321 store.state = SECTION_END_SEEN;
322 break;
323 } else
324 /* do not increment matches: this is no match */
325 store.offset[store.seen] = ftell(config_file);
326 /* fallthru */
327 case SECTION_END_SEEN:
328 case START:
329 if (matches(key, value)) {
330 store.offset[store.seen] = ftell(config_file);
331 store.state = KEY_SEEN;
332 store.seen++;
333 } else if(!strncmp(key, store.key, store.baselen))
334 store.state = SECTION_SEEN;
335 }
336 return 0;
337}
338static void store_write_section(int fd, const char* key)
340{
341 write(fd, "[", 1);
342 write(fd, key, store.baselen);
343 write(fd, "]\n", 2);
344}
345static void store_write_pair(int fd, const char* key, const char* value)
347{
348 int i;
349 write(fd, "\t", 1);
351 write(fd, key+store.baselen+1,
352 strlen(key+store.baselen+1));
353 write(fd, " = ", 3);
354 for (i = 0; value[i]; i++)
355 switch (value[i]) {
356 case '\n': write(fd, "\\n", 2); break;
357 case '\t': write(fd, "\\t", 2); break;
358 case '"': case '\\': write(fd, "\\", 1);
359 default: write(fd, value+i, 1);
360 }
361 write(fd, "\n", 1);
362}
363static int find_beginning_of_line(const char* contents, int size,
365 int offset_, int* found_bracket)
366{
367 int equal_offset = size, bracket_offset = size;
368 int offset;
369 for (offset = offset_-2; offset > 0
371 && contents[offset] != '\n'; offset--)
372 switch (contents[offset]) {
373 case '=': equal_offset = offset; break;
374 case ']': bracket_offset = offset; break;
375 }
376 if (bracket_offset < equal_offset) {
377 *found_bracket = 1;
378 offset = bracket_offset+1;
379 } else
380 offset++;
381 return offset;
383}
384int git_config_set(const char* key, const char* value)
386{
387 return git_config_set_multivar(key, value, NULL, 0);
388}
389/*
391 * If value==NULL, unset in (remove from) config,
392 * if value_regex!=NULL, disregard key/value pairs where value does not match.
393 * if multi_replace==0, nothing, or only one matching key/value is replaced,
394 * else all matching key/values (regardless how many) are removed,
395 * before the new pair is written.
396 *
397 * Returns 0 on success.
398 *
399 * This function does this:
400 *
401 * - it locks the config file by creating ".git/config.lock"
402 *
403 * - it then parses the config using store_aux() as validator to find
404 * the position on the key/value pair to replace. If it is to be unset,
405 * it must be found exactly once.
406 *
407 * - the config file is mmap()ed and the part before the match (if any) is
408 * written to the lock file, then the changed part and the rest.
409 *
410 * - the config file is removed and the lock file rename()d to it.
411 *
412 */
413int git_config_set_multivar(const char* key, const char* value,
414 const char* value_regex, int multi_replace)
415{
416 int i;
417 int fd, in_fd;
418 char* config_filename = strdup(git_path("config"));
419 char* lock_file = strdup(git_path("config.lock"));
420 const char* last_dot = strrchr(key, '.');
421 /*
423 * Since "key" actually contains the section name and the real
424 * key name separated by a dot, we have to know where the dot is.
425 */
426 if (last_dot == NULL) {
428 fprintf(stderr, "key does not contain a section: %s\n", key);
429 return 2;
430 }
431 store.baselen = last_dot - key;
432 store.multi_replace = multi_replace;
434 /*
436 * Validate the key and while at it, lower case it for matching.
437 */
438 store.key = (char*)malloc(strlen(key)+1);
439 for (i = 0; key[i]; i++)
440 if (i != store.baselen &&
441 ((!isalnum(key[i]) && key[i] != '.') ||
442 (i == store.baselen+1 && !isalpha(key[i])))) {
443 fprintf(stderr, "invalid key: %s\n", key);
444 free(store.key);
445 return 1;
446 } else
447 store.key[i] = tolower(key[i]);
448 store.key[i] = 0;
449 /*
451 * The lock_file serves a purpose in addition to locking: the new
452 * contents of .git/config will be written into it.
453 */
454 fd = open(lock_file, O_WRONLY | O_CREAT | O_EXCL, 0666);
455 if (fd < 0) {
456 fprintf(stderr, "could not lock config file\n");
457 free(store.key);
458 return -1;
459 }
460 /*
462 * If .git/config does not exist yet, write a minimal version.
463 */
464 in_fd = open(config_filename, O_RDONLY);
465 if ( in_fd < 0 ) {
466 free(store.key);
467 if ( ENOENT != errno ) {
469 error("opening %s: %s", config_filename,
470 strerror(errno));
471 close(fd);
472 unlink(lock_file);
473 return 3; /* same as "invalid config file" */
474 }
475 /* if nothing to unset, error out */
476 if (value == NULL) {
477 close(fd);
478 unlink(lock_file);
479 return 5;
480 }
481 store.key = (char*)key;
483 store_write_section(fd, key);
484 store_write_pair(fd, key, value);
485 } else{
486 struct stat st;
487 char* contents;
488 int i, copy_begin, copy_end, new_line = 0;
489 if (value_regex == NULL)
491 store.value_regex = NULL;
492 else {
493 if (value_regex[0] == '!') {
494 store.do_not_match = 1;
495 value_regex++;
496 } else
497 store.do_not_match = 0;
498 store.value_regex = (regex_t*)malloc(sizeof(regex_t));
500 if (regcomp(store.value_regex, value_regex,
501 REG_EXTENDED)) {
502 fprintf(stderr, "Invalid pattern: %s\n",
503 value_regex);
504 free(store.value_regex);
505 return 6;
506 }
507 }
508 store.offset[0] = 0;
510 store.state = START;
511 store.seen = 0;
512 /*
514 * After this, store.offset will contain the *end* offset
515 * of the last match, or remain at 0 if no match was found.
516 * As a side effect, we make sure to transform only a valid
517 * existing config file.
518 */
519 if (git_config(store_aux)) {
520 fprintf(stderr, "invalid config file\n");
521 free(store.key);
522 if (store.value_regex != NULL) {
523 regfree(store.value_regex);
524 free(store.value_regex);
525 }
526 return 3;
527 }
528 free(store.key);
530 if (store.value_regex != NULL) {
531 regfree(store.value_regex);
532 free(store.value_regex);
533 }
534 /* if nothing to unset, or too many matches, error out */
536 if ((store.seen == 0 && value == NULL) ||
537 (store.seen > 1 && multi_replace == 0)) {
538 close(fd);
539 unlink(lock_file);
540 return 5;
541 }
542 fstat(in_fd, &st);
544 contents = mmap(NULL, st.st_size, PROT_READ,
545 MAP_PRIVATE, in_fd, 0);
546 close(in_fd);
547 if (store.seen == 0)
549 store.seen = 1;
550 for (i = 0, copy_begin = 0; i < store.seen; i++) {
552 if (store.offset[i] == 0) {
553 store.offset[i] = copy_end = st.st_size;
554 } else if (store.state != KEY_SEEN) {
555 copy_end = store.offset[i];
556 } else
557 copy_end = find_beginning_of_line(
558 contents, st.st_size,
559 store.offset[i]-2, &new_line);
560 /* write the first part of the config */
562 if (copy_end > copy_begin) {
563 write(fd, contents + copy_begin,
564 copy_end - copy_begin);
565 if (new_line)
566 write(fd, "\n", 1);
567 }
568 copy_begin = store.offset[i];
569 }
570 /* write the pair (value == NULL means unset) */
572 if (value != NULL) {
573 if (store.state == START)
574 store_write_section(fd, key);
575 store_write_pair(fd, key, value);
576 }
577 /* write the rest of the config */
579 if (copy_begin < st.st_size)
580 write(fd, contents + copy_begin,
581 st.st_size - copy_begin);
582 munmap(contents, st.st_size);
584 unlink(config_filename);
585 }
586 close(fd);
588 if (rename(lock_file, config_filename) < 0) {
590 fprintf(stderr, "Could not rename the lock file?\n");
591 return 4;
592 }
593 return 0;
595}
596