Honor GIT_REFLOG_ACTION in git-rebase.
[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
10 #define MAXNAME (256)
11
12 static FILE *config_file;
13 static const char *config_file_name;
14 static int config_linenr;
15 static int get_next_char(void)
16 {
17         int c;
18         FILE *f;
19
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 }
40
41 static char *parse_value(void)
42 {
43         static char value[1024];
44         int quote = 0, comment = 0, len = 0, space = 0;
45
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 (!quote) {
63                         if (c == ';' || c == '#') {
64                                 comment = 1;
65                                 continue;
66                         }
67                 }
68                 if (space) {
69                         if (len)
70                                 value[len++] = ' ';
71                         space = 0;
72                 }
73                 if (c == '\\') {
74                         c = get_next_char();
75                         switch (c) {
76                         case '\n':
77                                 continue;
78                         case 't':
79                                 c = '\t';
80                                 break;
81                         case 'b':
82                                 c = '\b';
83                                 break;
84                         case 'n':
85                                 c = '\n';
86                                 break;
87                         /* Some characters escape as themselves */
88                         case '\\': case '"':
89                                 break;
90                         /* Reject unknown escape sequences */
91                         default:
92                                 return NULL;
93                         }
94                         value[len++] = c;
95                         continue;
96                 }
97                 if (c == '"') {
98                         quote = 1-quote;
99                         continue;
100                 }
101                 value[len++] = c;
102         }
103 }
104
105 static inline int iskeychar(int c)
106 {
107         return isalnum(c) || c == '-';
108 }
109
110 static int get_value(config_fn_t fn, char *name, unsigned int len)
111 {
112         int c;
113         char *value;
114
115         /* Get the full name */
116         for (;;) {
117                 c = get_next_char();
118                 if (c == EOF)
119                         break;
120                 if (!iskeychar(c))
121                         break;
122                 name[len++] = tolower(c);
123                 if (len >= MAXNAME)
124                         return -1;
125         }
126         name[len] = 0;
127         while (c == ' ' || c == '\t')
128                 c = get_next_char();
129
130         value = NULL;
131         if (c != '\n') {
132                 if (c != '=')
133                         return -1;
134                 value = parse_value();
135                 if (!value)
136                         return -1;
137         }
138         return fn(name, value);
139 }
140
141 static int get_extended_base_var(char *name, int baselen, int c)
142 {
143         do {
144                 if (c == '\n')
145                         return -1;
146                 c = get_next_char();
147         } while (isspace(c));
148
149         /* We require the format to be '[base "extension"]' */
150         if (c != '"')
151                 return -1;
152         name[baselen++] = '.';
153
154         for (;;) {
155                 int c = get_next_char();
156                 if (c == '\n')
157                         return -1;
158                 if (c == '"')
159                         break;
160                 if (c == '\\') {
161                         c = get_next_char();
162                         if (c == '\n')
163                                 return -1;
164                 }
165                 name[baselen++] = c;
166                 if (baselen > MAXNAME / 2)
167                         return -1;
168         }
169
170         /* Final ']' */
171         if (get_next_char() != ']')
172                 return -1;
173         return baselen;
174 }
175
176 static int get_base_var(char *name)
177 {
178         int baselen = 0;
179
180         for (;;) {
181                 int c = get_next_char();
182                 if (c == EOF)
183                         return -1;
184                 if (c == ']')
185                         return baselen;
186                 if (isspace(c))
187                         return get_extended_base_var(name, baselen, c);
188                 if (!iskeychar(c) && c != '.')
189                         return -1;
190                 if (baselen > MAXNAME / 2)
191                         return -1;
192                 name[baselen++] = tolower(c);
193         }
194 }
195
196 static int git_parse_file(config_fn_t fn)
197 {
198         int comment = 0;
199         int baselen = 0;
200         static char var[MAXNAME];
201
202         for (;;) {
203                 int c = get_next_char();
204                 if (c == '\n') {
205                         /* EOF? */
206                         if (!config_file)
207                                 return 0;
208                         comment = 0;
209                         continue;
210                 }
211                 if (comment || isspace(c))
212                         continue;
213                 if (c == '#' || c == ';') {
214                         comment = 1;
215                         continue;
216                 }
217                 if (c == '[') {
218                         baselen = get_base_var(var);
219                         if (baselen <= 0)
220                                 break;
221                         var[baselen++] = '.';
222                         var[baselen] = 0;
223                         continue;
224                 }
225                 if (!isalpha(c))
226                         break;
227                 var[baselen] = tolower(c);
228                 if (get_value(fn, var, baselen+1) < 0)
229                         break;
230         }
231         die("bad config file line %d in %s", config_linenr, config_file_name);
232 }
233
234 int git_config_int(const char *name, const char *value)
235 {
236         if (value && *value) {
237                 char *end;
238                 int val = strtol(value, &end, 0);
239                 if (!*end)
240                         return val;
241         }
242         die("bad config value for '%s' in %s", name, config_file_name);
243 }
244
245 int git_config_bool(const char *name, const char *value)
246 {
247         if (!value)
248                 return 1;
249         if (!*value)
250                 return 0;
251         if (!strcasecmp(value, "true") || !strcasecmp(value, "yes"))
252                 return 1;
253         if (!strcasecmp(value, "false") || !strcasecmp(value, "no"))
254                 return 0;
255         return git_config_int(name, value) != 0;
256 }
257
258 int git_default_config(const char *var, const char *value)
259 {
260         /* This needs a better name */
261         if (!strcmp(var, "core.filemode")) {
262                 trust_executable_bit = git_config_bool(var, value);
263                 return 0;
264         }
265
266         if (!strcmp(var, "core.ignorestat")) {
267                 assume_unchanged = git_config_bool(var, value);
268                 return 0;
269         }
270
271         if (!strcmp(var, "core.prefersymlinkrefs")) {
272                 prefer_symlink_refs = git_config_bool(var, value);
273                 return 0;
274         }
275
276         if (!strcmp(var, "core.logallrefupdates")) {
277                 log_all_ref_updates = git_config_bool(var, value);
278                 return 0;
279         }
280
281         if (!strcmp(var, "core.warnambiguousrefs")) {
282                 warn_ambiguous_refs = git_config_bool(var, value);
283                 return 0;
284         }
285
286         if (!strcmp(var, "core.legacyheaders")) {
287                 use_legacy_headers = git_config_bool(var, value);
288                 return 0;
289         }
290
291         if (!strcmp(var, "core.compression")) {
292                 int level = git_config_int(var, value);
293                 if (level == -1)
294                         level = Z_DEFAULT_COMPRESSION;
295                 else if (level < 0 || level > Z_BEST_COMPRESSION)
296                         die("bad zlib compression level %d", level);
297                 zlib_compression_level = level;
298                 return 0;
299         }
300
301         if (!strcmp(var, "user.name")) {
302                 strlcpy(git_default_name, value, sizeof(git_default_name));
303                 return 0;
304         }
305
306         if (!strcmp(var, "user.email")) {
307                 strlcpy(git_default_email, value, sizeof(git_default_email));
308                 return 0;
309         }
310
311         if (!strcmp(var, "i18n.commitencoding")) {
312                 strlcpy(git_commit_encoding, value, sizeof(git_commit_encoding));
313                 return 0;
314         }
315
316         if (!strcmp(var, "pager.color") || !strcmp(var, "color.pager")) {
317                 pager_use_color = git_config_bool(var,value);
318                 return 0;
319         }
320
321         /* Add other config variables here and to Documentation/config.txt. */
322         return 0;
323 }
324
325 int git_config_from_file(config_fn_t fn, const char *filename)
326 {
327         int ret;
328         FILE *f = fopen(filename, "r");
329
330         ret = -1;
331         if (f) {
332                 config_file = f;
333                 config_file_name = filename;
334                 config_linenr = 1;
335                 ret = git_parse_file(fn);
336                 fclose(f);
337                 config_file_name = NULL;
338         }
339         return ret;
340 }
341
342 int git_config(config_fn_t fn)
343 {
344         int ret = 0;
345         char *repo_config = NULL;
346         const char *home = NULL, *filename;
347
348         /* $GIT_CONFIG makes git read _only_ the given config file,
349          * $GIT_CONFIG_LOCAL will make it process it in addition to the
350          * global config file, the same way it would the per-repository
351          * config file otherwise. */
352         filename = getenv(CONFIG_ENVIRONMENT);
353         if (!filename) {
354                 home = getenv("HOME");
355                 filename = getenv(CONFIG_LOCAL_ENVIRONMENT);
356                 if (!filename)
357                         filename = repo_config = xstrdup(git_path("config"));
358         }
359
360         if (home) {
361                 char *user_config = xstrdup(mkpath("%s/.gitconfig", home));
362                 if (!access(user_config, R_OK))
363                         ret = git_config_from_file(fn, user_config);
364                 free(user_config);
365         }
366
367         ret += git_config_from_file(fn, filename);
368         free(repo_config);
369         return ret;
370 }
371
372 /*
373  * Find all the stuff for git_config_set() below.
374  */
375
376 #define MAX_MATCHES 512
377
378 static struct {
379         int baselen;
380         char* key;
381         int do_not_match;
382         regex_t* value_regex;
383         int multi_replace;
384         off_t offset[MAX_MATCHES];
385         enum { START, SECTION_SEEN, SECTION_END_SEEN, KEY_SEEN } state;
386         int seen;
387 } store;
388
389 static int matches(const char* key, const char* value)
390 {
391         return !strcmp(key, store.key) &&
392                 (store.value_regex == NULL ||
393                  (store.do_not_match ^
394                   !regexec(store.value_regex, value, 0, NULL, 0)));
395 }
396
397 static int store_aux(const char* key, const char* value)
398 {
399         switch (store.state) {
400         case KEY_SEEN:
401                 if (matches(key, value)) {
402                         if (store.seen == 1 && store.multi_replace == 0) {
403                                 fprintf(stderr,
404                                         "Warning: %s has multiple values\n",
405                                         key);
406                         } else if (store.seen >= MAX_MATCHES) {
407                                 fprintf(stderr, "Too many matches\n");
408                                 return 1;
409                         }
410
411                         store.offset[store.seen] = ftell(config_file);
412                         store.seen++;
413                 }
414                 break;
415         case SECTION_SEEN:
416                 if (strncmp(key, store.key, store.baselen+1)) {
417                         store.state = SECTION_END_SEEN;
418                         break;
419                 } else
420                         /* do not increment matches: this is no match */
421                         store.offset[store.seen] = ftell(config_file);
422                 /* fallthru */
423         case SECTION_END_SEEN:
424         case START:
425                 if (matches(key, value)) {
426                         store.offset[store.seen] = ftell(config_file);
427                         store.state = KEY_SEEN;
428                         store.seen++;
429                 } else {
430                         if (strrchr(key, '.') - key == store.baselen &&
431                               !strncmp(key, store.key, store.baselen)) {
432                                         store.state = SECTION_SEEN;
433                                         store.offset[store.seen] = ftell(config_file);
434                         }
435                 }
436         }
437         return 0;
438 }
439
440 static void store_write_section(int fd, const char* key)
441 {
442         const char *dot = strchr(key, '.');
443         int len1 = store.baselen, len2 = -1;
444
445         dot = strchr(key, '.');
446         if (dot) {
447                 int dotlen = dot - key;
448                 if (dotlen < len1) {
449                         len2 = len1 - dotlen - 1;
450                         len1 = dotlen;
451                 }
452         }
453
454         write(fd, "[", 1);
455         write(fd, key, len1);
456         if (len2 >= 0) {
457                 write(fd, " \"", 2);
458                 while (--len2 >= 0) {
459                         unsigned char c = *++dot;
460                         if (c == '"')
461                                 write(fd, "\\", 1);
462                         write(fd, &c, 1);
463                 }
464                 write(fd, "\"", 1);
465         }
466         write(fd, "]\n", 2);
467 }
468
469 static void store_write_pair(int fd, const char* key, const char* value)
470 {
471         int i;
472
473         write(fd, "\t", 1);
474         write(fd, key+store.baselen+1,
475                 strlen(key+store.baselen+1));
476         write(fd, " = ", 3);
477         for (i = 0; value[i]; i++)
478                 switch (value[i]) {
479                 case '\n': write(fd, "\\n", 2); break;
480                 case '\t': write(fd, "\\t", 2); break;
481                 case '"': case '\\': write(fd, "\\", 1);
482                 default: write(fd, value+i, 1);
483         }
484         write(fd, "\n", 1);
485 }
486
487 static int find_beginning_of_line(const char* contents, int size,
488         int offset_, int* found_bracket)
489 {
490         int equal_offset = size, bracket_offset = size;
491         int offset;
492
493         for (offset = offset_-2; offset > 0 
494                         && contents[offset] != '\n'; offset--)
495                 switch (contents[offset]) {
496                         case '=': equal_offset = offset; break;
497                         case ']': bracket_offset = offset; break;
498                 }
499         if (bracket_offset < equal_offset) {
500                 *found_bracket = 1;
501                 offset = bracket_offset+1;
502         } else
503                 offset++;
504
505         return offset;
506 }
507
508 int git_config_set(const char* key, const char* value)
509 {
510         return git_config_set_multivar(key, value, NULL, 0);
511 }
512
513 /*
514  * If value==NULL, unset in (remove from) config,
515  * if value_regex!=NULL, disregard key/value pairs where value does not match.
516  * if multi_replace==0, nothing, or only one matching key/value is replaced,
517  *     else all matching key/values (regardless how many) are removed,
518  *     before the new pair is written.
519  *
520  * Returns 0 on success.
521  *
522  * This function does this:
523  *
524  * - it locks the config file by creating ".git/config.lock"
525  *
526  * - it then parses the config using store_aux() as validator to find
527  *   the position on the key/value pair to replace. If it is to be unset,
528  *   it must be found exactly once.
529  *
530  * - the config file is mmap()ed and the part before the match (if any) is
531  *   written to the lock file, then the changed part and the rest.
532  *
533  * - the config file is removed and the lock file rename()d to it.
534  *
535  */
536 int git_config_set_multivar(const char* key, const char* value,
537         const char* value_regex, int multi_replace)
538 {
539         int i, dot;
540         int fd = -1, in_fd;
541         int ret;
542         char* config_filename;
543         char* lock_file;
544         const char* last_dot = strrchr(key, '.');
545
546         config_filename = getenv(CONFIG_ENVIRONMENT);
547         if (!config_filename) {
548                 config_filename = getenv(CONFIG_LOCAL_ENVIRONMENT);
549                 if (!config_filename)
550                         config_filename  = git_path("config");
551         }
552         config_filename = xstrdup(config_filename);
553         lock_file = xstrdup(mkpath("%s.lock", config_filename));
554
555         /*
556          * Since "key" actually contains the section name and the real
557          * key name separated by a dot, we have to know where the dot is.
558          */
559
560         if (last_dot == NULL) {
561                 fprintf(stderr, "key does not contain a section: %s\n", key);
562                 ret = 2;
563                 goto out_free;
564         }
565         store.baselen = last_dot - key;
566
567         store.multi_replace = multi_replace;
568
569         /*
570          * Validate the key and while at it, lower case it for matching.
571          */
572         store.key = xmalloc(strlen(key) + 1);
573         dot = 0;
574         for (i = 0; key[i]; i++) {
575                 unsigned char c = key[i];
576                 if (c == '.')
577                         dot = 1;
578                 /* Leave the extended basename untouched.. */
579                 if (!dot || i > store.baselen) {
580                         if (!iskeychar(c) || (i == store.baselen+1 && !isalpha(c))) {
581                                 fprintf(stderr, "invalid key: %s\n", key);
582                                 free(store.key);
583                                 ret = 1;
584                                 goto out_free;
585                         }
586                         c = tolower(c);
587                 }
588                 store.key[i] = c;
589         }
590         store.key[i] = 0;
591
592         /*
593          * The lock_file serves a purpose in addition to locking: the new
594          * contents of .git/config will be written into it.
595          */
596         fd = open(lock_file, O_WRONLY | O_CREAT | O_EXCL, 0666);
597         if (fd < 0 || adjust_shared_perm(lock_file)) {
598                 fprintf(stderr, "could not lock config file\n");
599                 free(store.key);
600                 ret = -1;
601                 goto out_free;
602         }
603
604         /*
605          * If .git/config does not exist yet, write a minimal version.
606          */
607         in_fd = open(config_filename, O_RDONLY);
608         if ( in_fd < 0 ) {
609                 free(store.key);
610
611                 if ( ENOENT != errno ) {
612                         error("opening %s: %s", config_filename,
613                               strerror(errno));
614                         ret = 3; /* same as "invalid config file" */
615                         goto out_free;
616                 }
617                 /* if nothing to unset, error out */
618                 if (value == NULL) {
619                         ret = 5;
620                         goto out_free;
621                 }
622
623                 store.key = (char*)key;
624                 store_write_section(fd, key);
625                 store_write_pair(fd, key, value);
626         } else{
627                 struct stat st;
628                 char* contents;
629                 int i, copy_begin, copy_end, new_line = 0;
630
631                 if (value_regex == NULL)
632                         store.value_regex = NULL;
633                 else {
634                         if (value_regex[0] == '!') {
635                                 store.do_not_match = 1;
636                                 value_regex++;
637                         } else
638                                 store.do_not_match = 0;
639
640                         store.value_regex = (regex_t*)xmalloc(sizeof(regex_t));
641                         if (regcomp(store.value_regex, value_regex,
642                                         REG_EXTENDED)) {
643                                 fprintf(stderr, "Invalid pattern: %s\n",
644                                         value_regex);
645                                 free(store.value_regex);
646                                 ret = 6;
647                                 goto out_free;
648                         }
649                 }
650
651                 store.offset[0] = 0;
652                 store.state = START;
653                 store.seen = 0;
654
655                 /*
656                  * After this, store.offset will contain the *end* offset
657                  * of the last match, or remain at 0 if no match was found.
658                  * As a side effect, we make sure to transform only a valid
659                  * existing config file.
660                  */
661                 if (git_config_from_file(store_aux, config_filename)) {
662                         fprintf(stderr, "invalid config file\n");
663                         free(store.key);
664                         if (store.value_regex != NULL) {
665                                 regfree(store.value_regex);
666                                 free(store.value_regex);
667                         }
668                         ret = 3;
669                         goto out_free;
670                 }
671
672                 free(store.key);
673                 if (store.value_regex != NULL) {
674                         regfree(store.value_regex);
675                         free(store.value_regex);
676                 }
677
678                 /* if nothing to unset, or too many matches, error out */
679                 if ((store.seen == 0 && value == NULL) ||
680                                 (store.seen > 1 && multi_replace == 0)) {
681                         ret = 5;
682                         goto out_free;
683                 }
684
685                 fstat(in_fd, &st);
686                 contents = mmap(NULL, st.st_size, PROT_READ,
687                         MAP_PRIVATE, in_fd, 0);
688                 close(in_fd);
689
690                 if (store.seen == 0)
691                         store.seen = 1;
692
693                 for (i = 0, copy_begin = 0; i < store.seen; i++) {
694                         if (store.offset[i] == 0) {
695                                 store.offset[i] = copy_end = st.st_size;
696                         } else if (store.state != KEY_SEEN) {
697                                 copy_end = store.offset[i];
698                         } else
699                                 copy_end = find_beginning_of_line(
700                                         contents, st.st_size,
701                                         store.offset[i]-2, &new_line);
702
703                         /* write the first part of the config */
704                         if (copy_end > copy_begin) {
705                                 write(fd, contents + copy_begin,
706                                 copy_end - copy_begin);
707                                 if (new_line)
708                                         write(fd, "\n", 1);
709                         }
710                         copy_begin = store.offset[i];
711                 }
712
713                 /* write the pair (value == NULL means unset) */
714                 if (value != NULL) {
715                         if (store.state == START)
716                                 store_write_section(fd, key);
717                         store_write_pair(fd, key, value);
718                 }
719
720                 /* write the rest of the config */
721                 if (copy_begin < st.st_size)
722                         write(fd, contents + copy_begin,
723                                 st.st_size - copy_begin);
724
725                 munmap(contents, st.st_size);
726                 unlink(config_filename);
727         }
728
729         if (rename(lock_file, config_filename) < 0) {
730                 fprintf(stderr, "Could not rename the lock file?\n");
731                 ret = 4;
732                 goto out_free;
733         }
734
735         ret = 0;
736
737 out_free:
738         if (0 <= fd)
739                 close(fd);
740         free(config_filename);
741         if (lock_file) {
742                 unlink(lock_file);
743                 free(lock_file);
744         }
745         return ret;
746 }
747
748 int git_config_rename_section(const char *old_name, const char *new_name)
749 {
750         int ret = 0;
751         char *config_filename;
752         struct lock_file *lock = xcalloc(sizeof(struct lock_file), 1);
753         int out_fd;
754         char buf[1024];
755
756         config_filename = getenv(CONFIG_ENVIRONMENT);
757         if (!config_filename) {
758                 config_filename = getenv(CONFIG_LOCAL_ENVIRONMENT);
759                 if (!config_filename)
760                         config_filename  = git_path("config");
761         }
762         config_filename = xstrdup(config_filename);
763         out_fd = hold_lock_file_for_update(lock, config_filename, 0);
764         if (out_fd < 0) {
765                 ret = error("Could not lock config file!");
766                 goto out;
767         }
768
769         if (!(config_file = fopen(config_filename, "rb"))) {
770                 ret = error("Could not open config file!");
771                 goto out;
772         }
773
774         while (fgets(buf, sizeof(buf), config_file)) {
775                 int i;
776                 for (i = 0; buf[i] && isspace(buf[i]); i++)
777                         ; /* do nothing */
778                 if (buf[i] == '[') {
779                         /* it's a section */
780                         int j = 0, dot = 0;
781                         for (i++; buf[i] && buf[i] != ']'; i++) {
782                                 if (!dot && isspace(buf[i])) {
783                                         dot = 1;
784                                         if (old_name[j++] != '.')
785                                                 break;
786                                         for (i++; isspace(buf[i]); i++)
787                                                 ; /* do nothing */
788                                         if (buf[i] != '"')
789                                                 break;
790                                         continue;
791                                 }
792                                 if (buf[i] == '\\' && dot)
793                                         i++;
794                                 else if (buf[i] == '"' && dot) {
795                                         for (i++; isspace(buf[i]); i++)
796                                                 ; /* do_nothing */
797                                         break;
798                                 }
799                                 if (buf[i] != old_name[j++])
800                                         break;
801                         }
802                         if (buf[i] == ']') {
803                                 /* old_name matches */
804                                 ret++;
805                                 store.baselen = strlen(new_name);
806                                 store_write_section(out_fd, new_name);
807                                 continue;
808                         }
809                 }
810                 write(out_fd, buf, strlen(buf));
811         }
812         fclose(config_file);
813         if (close(out_fd) || commit_lock_file(lock) < 0)
814                 ret = error("Cannot commit config file!");
815  out:
816         free(config_filename);
817         return ret;
818 }
819