builtin-grep: do not use setup_revisions()
[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 (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
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