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.warnambiguousrefs")) {
273 warn_ambiguous_refs = git_config_bool(var, value);
274 return 0;
275 }
276 if (!strcmp(var, "user.name")) {
278 strncpy(git_default_name, value, sizeof(git_default_name));
279 return 0;
280 }
281 if (!strcmp(var, "user.email")) {
283 strncpy(git_default_email, value, sizeof(git_default_email));
284 return 0;
285 }
286 if (!strcmp(var, "i18n.commitencoding")) {
288 strncpy(git_commit_encoding, value, sizeof(git_commit_encoding));
289 return 0;
290 }
291 /* Add other config variables here and to Documentation/config.txt. */
293 return 0;
294}
295int git_config_from_file(config_fn_t fn, const char *filename)
297{
298 int ret;
299 FILE *f = fopen(filename, "r");
300 ret = -1;
302 if (f) {
303 config_file = f;
304 config_file_name = filename;
305 config_linenr = 1;
306 ret = git_parse_file(fn);
307 fclose(f);
308 config_file_name = NULL;
309 }
310 return ret;
311}
312int git_config(config_fn_t fn)
314{
315 return git_config_from_file(fn, git_path("config"));
316}
317/*
319 * Find all the stuff for git_config_set() below.
320 */
321#define MAX_MATCHES 512
323static struct {
325 int baselen;
326 char* key;
327 int do_not_match;
328 regex_t* value_regex;
329 int multi_replace;
330 off_t offset[MAX_MATCHES];
331 enum { START, SECTION_SEEN, SECTION_END_SEEN, KEY_SEEN } state;
332 int seen;
333} store;
334static int matches(const char* key, const char* value)
336{
337 return !strcmp(key, store.key) &&
338 (store.value_regex == NULL ||
339 (store.do_not_match ^
340 !regexec(store.value_regex, value, 0, NULL, 0)));
341}
342static int store_aux(const char* key, const char* value)
344{
345 switch (store.state) {
346 case KEY_SEEN:
347 if (matches(key, value)) {
348 if (store.seen == 1 && store.multi_replace == 0) {
349 fprintf(stderr,
350 "Warning: %s has multiple values\n",
351 key);
352 } else if (store.seen >= MAX_MATCHES) {
353 fprintf(stderr, "Too many matches\n");
354 return 1;
355 }
356 store.offset[store.seen] = ftell(config_file);
358 store.seen++;
359 }
360 break;
361 case SECTION_SEEN:
362 if (strncmp(key, store.key, store.baselen+1)) {
363 store.state = SECTION_END_SEEN;
364 break;
365 } else
366 /* do not increment matches: this is no match */
367 store.offset[store.seen] = ftell(config_file);
368 /* fallthru */
369 case SECTION_END_SEEN:
370 case START:
371 if (matches(key, value)) {
372 store.offset[store.seen] = ftell(config_file);
373 store.state = KEY_SEEN;
374 store.seen++;
375 } else {
376 if (strrchr(key, '.') - key == store.baselen &&
377 !strncmp(key, store.key, store.baselen)) {
378 store.state = SECTION_SEEN;
379 store.offset[store.seen] = ftell(config_file);
380 }
381 }
382 }
383 return 0;
384}
385static void store_write_section(int fd, const char* key)
387{
388 const char *dot = strchr(key, '.');
389 int len1 = store.baselen, len2 = -1;
390 dot = strchr(key, '.');
392 if (dot) {
393 int dotlen = dot - key;
394 if (dotlen < len1) {
395 len2 = len1 - dotlen - 1;
396 len1 = dotlen;
397 }
398 }
399 write(fd, "[", 1);
401 write(fd, key, len1);
402 if (len2 >= 0) {
403 write(fd, " \"", 2);
404 while (--len2 >= 0) {
405 unsigned char c = *++dot;
406 if (c == '"')
407 write(fd, "\\", 1);
408 write(fd, &c, 1);
409 }
410 write(fd, "\"", 1);
411 }
412 write(fd, "]\n", 2);
413}
414static void store_write_pair(int fd, const char* key, const char* value)
416{
417 int i;
418 write(fd, "\t", 1);
420 write(fd, key+store.baselen+1,
421 strlen(key+store.baselen+1));
422 write(fd, " = ", 3);
423 for (i = 0; value[i]; i++)
424 switch (value[i]) {
425 case '\n': write(fd, "\\n", 2); break;
426 case '\t': write(fd, "\\t", 2); break;
427 case '"': case '\\': write(fd, "\\", 1);
428 default: write(fd, value+i, 1);
429 }
430 write(fd, "\n", 1);
431}
432static int find_beginning_of_line(const char* contents, int size,
434 int offset_, int* found_bracket)
435{
436 int equal_offset = size, bracket_offset = size;
437 int offset;
438 for (offset = offset_-2; offset > 0
440 && contents[offset] != '\n'; offset--)
441 switch (contents[offset]) {
442 case '=': equal_offset = offset; break;
443 case ']': bracket_offset = offset; break;
444 }
445 if (bracket_offset < equal_offset) {
446 *found_bracket = 1;
447 offset = bracket_offset+1;
448 } else
449 offset++;
450 return offset;
452}
453int git_config_set(const char* key, const char* value)
455{
456 return git_config_set_multivar(key, value, NULL, 0);
457}
458/*
460 * If value==NULL, unset in (remove from) config,
461 * if value_regex!=NULL, disregard key/value pairs where value does not match.
462 * if multi_replace==0, nothing, or only one matching key/value is replaced,
463 * else all matching key/values (regardless how many) are removed,
464 * before the new pair is written.
465 *
466 * Returns 0 on success.
467 *
468 * This function does this:
469 *
470 * - it locks the config file by creating ".git/config.lock"
471 *
472 * - it then parses the config using store_aux() as validator to find
473 * the position on the key/value pair to replace. If it is to be unset,
474 * it must be found exactly once.
475 *
476 * - the config file is mmap()ed and the part before the match (if any) is
477 * written to the lock file, then the changed part and the rest.
478 *
479 * - the config file is removed and the lock file rename()d to it.
480 *
481 */
482int git_config_set_multivar(const char* key, const char* value,
483 const char* value_regex, int multi_replace)
484{
485 int i, dot;
486 int fd = -1, in_fd;
487 int ret;
488 char* config_filename = strdup(git_path("config"));
489 char* lock_file = strdup(git_path("config.lock"));
490 const char* last_dot = strrchr(key, '.');
491 /*
493 * Since "key" actually contains the section name and the real
494 * key name separated by a dot, we have to know where the dot is.
495 */
496 if (last_dot == NULL) {
498 fprintf(stderr, "key does not contain a section: %s\n", key);
499 ret = 2;
500 goto out_free;
501 }
502 store.baselen = last_dot - key;
503 store.multi_replace = multi_replace;
505 /*
507 * Validate the key and while at it, lower case it for matching.
508 */
509 store.key = (char*)malloc(strlen(key)+1);
510 dot = 0;
511 for (i = 0; key[i]; i++) {
512 unsigned char c = key[i];
513 if (c == '.')
514 dot = 1;
515 /* Leave the extended basename untouched.. */
516 if (!dot || i > store.baselen) {
517 if (!isalnum(c) || (i == store.baselen+1 && !isalpha(c))) {
518 fprintf(stderr, "invalid key: %s\n", key);
519 free(store.key);
520 ret = 1;
521 goto out_free;
522 }
523 c = tolower(c);
524 }
525 store.key[i] = c;
526 }
527 store.key[i] = 0;
528 /*
530 * The lock_file serves a purpose in addition to locking: the new
531 * contents of .git/config will be written into it.
532 */
533 fd = open(lock_file, O_WRONLY | O_CREAT | O_EXCL, 0666);
534 if (fd < 0) {
535 fprintf(stderr, "could not lock config file\n");
536 free(store.key);
537 ret = -1;
538 goto out_free;
539 }
540 /*
542 * If .git/config does not exist yet, write a minimal version.
543 */
544 in_fd = open(config_filename, O_RDONLY);
545 if ( in_fd < 0 ) {
546 free(store.key);
547 if ( ENOENT != errno ) {
549 error("opening %s: %s", config_filename,
550 strerror(errno));
551 ret = 3; /* same as "invalid config file" */
552 goto out_free;
553 }
554 /* if nothing to unset, error out */
555 if (value == NULL) {
556 ret = 5;
557 goto out_free;
558 }
559 store.key = (char*)key;
561 store_write_section(fd, key);
562 store_write_pair(fd, key, value);
563 } else{
564 struct stat st;
565 char* contents;
566 int i, copy_begin, copy_end, new_line = 0;
567 if (value_regex == NULL)
569 store.value_regex = NULL;
570 else {
571 if (value_regex[0] == '!') {
572 store.do_not_match = 1;
573 value_regex++;
574 } else
575 store.do_not_match = 0;
576 store.value_regex = (regex_t*)malloc(sizeof(regex_t));
578 if (regcomp(store.value_regex, value_regex,
579 REG_EXTENDED)) {
580 fprintf(stderr, "Invalid pattern: %s\n",
581 value_regex);
582 free(store.value_regex);
583 ret = 6;
584 goto out_free;
585 }
586 }
587 store.offset[0] = 0;
589 store.state = START;
590 store.seen = 0;
591 /*
593 * After this, store.offset will contain the *end* offset
594 * of the last match, or remain at 0 if no match was found.
595 * As a side effect, we make sure to transform only a valid
596 * existing config file.
597 */
598 if (git_config(store_aux)) {
599 fprintf(stderr, "invalid config file\n");
600 free(store.key);
601 if (store.value_regex != NULL) {
602 regfree(store.value_regex);
603 free(store.value_regex);
604 }
605 ret = 3;
606 goto out_free;
607 }
608 free(store.key);
610 if (store.value_regex != NULL) {
611 regfree(store.value_regex);
612 free(store.value_regex);
613 }
614 /* if nothing to unset, or too many matches, error out */
616 if ((store.seen == 0 && value == NULL) ||
617 (store.seen > 1 && multi_replace == 0)) {
618 ret = 5;
619 goto out_free;
620 }
621 fstat(in_fd, &st);
623 contents = mmap(NULL, st.st_size, PROT_READ,
624 MAP_PRIVATE, in_fd, 0);
625 close(in_fd);
626 if (store.seen == 0)
628 store.seen = 1;
629 for (i = 0, copy_begin = 0; i < store.seen; i++) {
631 if (store.offset[i] == 0) {
632 store.offset[i] = copy_end = st.st_size;
633 } else if (store.state != KEY_SEEN) {
634 copy_end = store.offset[i];
635 } else
636 copy_end = find_beginning_of_line(
637 contents, st.st_size,
638 store.offset[i]-2, &new_line);
639 /* write the first part of the config */
641 if (copy_end > copy_begin) {
642 write(fd, contents + copy_begin,
643 copy_end - copy_begin);
644 if (new_line)
645 write(fd, "\n", 1);
646 }
647 copy_begin = store.offset[i];
648 }
649 /* write the pair (value == NULL means unset) */
651 if (value != NULL) {
652 if (store.state == START)
653 store_write_section(fd, key);
654 store_write_pair(fd, key, value);
655 }
656 /* write the rest of the config */
658 if (copy_begin < st.st_size)
659 write(fd, contents + copy_begin,
660 st.st_size - copy_begin);
661 munmap(contents, st.st_size);
663 unlink(config_filename);
664 }
665 if (rename(lock_file, config_filename) < 0) {
667 fprintf(stderr, "Could not rename the lock file?\n");
668 ret = 4;
669 goto out_free;
670 }
671 ret = 0;
673out_free:
675 if (0 <= fd)
676 close(fd);
677 if (config_filename)
678 free(config_filename);
679 if (lock_file) {
680 unlink(lock_file);
681 free(lock_file);
682 }
683 return ret;
684}
685