Use {web,instaweb,help}.browser config options.
[git/dscho.git] / config.c
blobed96213c44265289c26d46edaaf740cebd0b4c86
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 "exec_cmd.h"
11 #define MAXNAME (256)
13 static FILE *config_file;
14 static const char *config_file_name;
15 static int config_linenr;
16 static int zlib_compression_seen;
18 static int get_next_char(void)
20         int c;
21         FILE *f;
23         c = '\n';
24         if ((f = config_file) != NULL) {
25                 c = fgetc(f);
26                 if (c == '\r') {
27                         /* DOS like systems */
28                         c = fgetc(f);
29                         if (c != '\n') {
30                                 ungetc(c, f);
31                                 c = '\r';
32                         }
33                 }
34                 if (c == '\n')
35                         config_linenr++;
36                 if (c == EOF) {
37                         config_file = NULL;
38                         c = '\n';
39                 }
40         }
41         return c;
44 static char *parse_value(void)
46         static char value[1024];
47         int quote = 0, comment = 0, len = 0, space = 0;
49         for (;;) {
50                 int c = get_next_char();
51                 if (len >= sizeof(value))
52                         return NULL;
53                 if (c == '\n') {
54                         if (quote)
55                                 return NULL;
56                         value[len] = 0;
57                         return value;
58                 }
59                 if (comment)
60                         continue;
61                 if (isspace(c) && !quote) {
62                         space = 1;
63                         continue;
64                 }
65                 if (!quote) {
66                         if (c == ';' || c == '#') {
67                                 comment = 1;
68                                 continue;
69                         }
70                 }
71                 if (space) {
72                         if (len)
73                                 value[len++] = ' ';
74                         space = 0;
75                 }
76                 if (c == '\\') {
77                         c = get_next_char();
78                         switch (c) {
79                         case '\n':
80                                 continue;
81                         case 't':
82                                 c = '\t';
83                                 break;
84                         case 'b':
85                                 c = '\b';
86                                 break;
87                         case 'n':
88                                 c = '\n';
89                                 break;
90                         /* Some characters escape as themselves */
91                         case '\\': case '"':
92                                 break;
93                         /* Reject unknown escape sequences */
94                         default:
95                                 return NULL;
96                         }
97                         value[len++] = c;
98                         continue;
99                 }
100                 if (c == '"') {
101                         quote = 1-quote;
102                         continue;
103                 }
104                 value[len++] = c;
105         }
108 static inline int iskeychar(int c)
110         return isalnum(c) || c == '-';
113 static int get_value(config_fn_t fn, char *name, unsigned int len)
115         int c;
116         char *value;
118         /* Get the full name */
119         for (;;) {
120                 c = get_next_char();
121                 if (c == EOF)
122                         break;
123                 if (!iskeychar(c))
124                         break;
125                 name[len++] = tolower(c);
126                 if (len >= MAXNAME)
127                         return -1;
128         }
129         name[len] = 0;
130         while (c == ' ' || c == '\t')
131                 c = get_next_char();
133         value = NULL;
134         if (c != '\n') {
135                 if (c != '=')
136                         return -1;
137                 value = parse_value();
138                 if (!value)
139                         return -1;
140         }
141         return fn(name, value);
144 static int get_extended_base_var(char *name, int baselen, int c)
146         do {
147                 if (c == '\n')
148                         return -1;
149                 c = get_next_char();
150         } while (isspace(c));
152         /* We require the format to be '[base "extension"]' */
153         if (c != '"')
154                 return -1;
155         name[baselen++] = '.';
157         for (;;) {
158                 int c = get_next_char();
159                 if (c == '\n')
160                         return -1;
161                 if (c == '"')
162                         break;
163                 if (c == '\\') {
164                         c = get_next_char();
165                         if (c == '\n')
166                                 return -1;
167                 }
168                 name[baselen++] = c;
169                 if (baselen > MAXNAME / 2)
170                         return -1;
171         }
173         /* Final ']' */
174         if (get_next_char() != ']')
175                 return -1;
176         return baselen;
179 static int get_base_var(char *name)
181         int baselen = 0;
183         for (;;) {
184                 int c = get_next_char();
185                 if (c == EOF)
186                         return -1;
187                 if (c == ']')
188                         return baselen;
189                 if (isspace(c))
190                         return get_extended_base_var(name, baselen, c);
191                 if (!iskeychar(c) && c != '.')
192                         return -1;
193                 if (baselen > MAXNAME / 2)
194                         return -1;
195                 name[baselen++] = tolower(c);
196         }
199 static int git_parse_file(config_fn_t fn)
201         int comment = 0;
202         int baselen = 0;
203         static char var[MAXNAME];
205         for (;;) {
206                 int c = get_next_char();
207                 if (c == '\n') {
208                         /* EOF? */
209                         if (!config_file)
210                                 return 0;
211                         comment = 0;
212                         continue;
213                 }
214                 if (comment || isspace(c))
215                         continue;
216                 if (c == '#' || c == ';') {
217                         comment = 1;
218                         continue;
219                 }
220                 if (c == '[') {
221                         baselen = get_base_var(var);
222                         if (baselen <= 0)
223                                 break;
224                         var[baselen++] = '.';
225                         var[baselen] = 0;
226                         continue;
227                 }
228                 if (!isalpha(c))
229                         break;
230                 var[baselen] = tolower(c);
231                 if (get_value(fn, var, baselen+1) < 0)
232                         break;
233         }
234         die("bad config file line %d in %s", config_linenr, config_file_name);
237 static unsigned long get_unit_factor(const char *end)
239         if (!*end)
240                 return 1;
241         else if (!strcasecmp(end, "k"))
242                 return 1024;
243         else if (!strcasecmp(end, "m"))
244                 return 1024 * 1024;
245         else if (!strcasecmp(end, "g"))
246                 return 1024 * 1024 * 1024;
247         die("unknown unit: '%s'", end);
250 int git_parse_long(const char *value, long *ret)
252         if (value && *value) {
253                 char *end;
254                 long val = strtol(value, &end, 0);
255                 *ret = val * get_unit_factor(end);
256                 return 1;
257         }
258         return 0;
261 int git_parse_ulong(const char *value, unsigned long *ret)
263         if (value && *value) {
264                 char *end;
265                 unsigned long val = strtoul(value, &end, 0);
266                 *ret = val * get_unit_factor(end);
267                 return 1;
268         }
269         return 0;
272 int git_config_int(const char *name, const char *value)
274         long ret;
275         if (!git_parse_long(value, &ret))
276                 die("bad config value for '%s' in %s", name, config_file_name);
277         return ret;
280 unsigned long git_config_ulong(const char *name, const char *value)
282         unsigned long ret;
283         if (!git_parse_ulong(value, &ret))
284                 die("bad config value for '%s' in %s", name, config_file_name);
285         return ret;
288 int git_config_bool(const char *name, const char *value)
290         if (!value)
291                 return 1;
292         if (!*value)
293                 return 0;
294         if (!strcasecmp(value, "true") || !strcasecmp(value, "yes"))
295                 return 1;
296         if (!strcasecmp(value, "false") || !strcasecmp(value, "no"))
297                 return 0;
298         return git_config_int(name, value) != 0;
301 int git_default_config(const char *var, const char *value)
303         /* This needs a better name */
304         if (!strcmp(var, "core.filemode")) {
305                 trust_executable_bit = git_config_bool(var, value);
306                 return 0;
307         }
309         if (!strcmp(var, "core.quotepath")) {
310                 quote_path_fully = git_config_bool(var, value);
311                 return 0;
312         }
314         if (!strcmp(var, "core.symlinks")) {
315                 has_symlinks = git_config_bool(var, value);
316                 return 0;
317         }
319         if (!strcmp(var, "core.bare")) {
320                 is_bare_repository_cfg = git_config_bool(var, value);
321                 return 0;
322         }
324         if (!strcmp(var, "core.ignorestat")) {
325                 assume_unchanged = git_config_bool(var, value);
326                 return 0;
327         }
329         if (!strcmp(var, "core.prefersymlinkrefs")) {
330                 prefer_symlink_refs = git_config_bool(var, value);
331                 return 0;
332         }
334         if (!strcmp(var, "core.logallrefupdates")) {
335                 log_all_ref_updates = git_config_bool(var, value);
336                 return 0;
337         }
339         if (!strcmp(var, "core.warnambiguousrefs")) {
340                 warn_ambiguous_refs = git_config_bool(var, value);
341                 return 0;
342         }
344         if (!strcmp(var, "core.loosecompression")) {
345                 int level = git_config_int(var, value);
346                 if (level == -1)
347                         level = Z_DEFAULT_COMPRESSION;
348                 else if (level < 0 || level > Z_BEST_COMPRESSION)
349                         die("bad zlib compression level %d", level);
350                 zlib_compression_level = level;
351                 zlib_compression_seen = 1;
352                 return 0;
353         }
355         if (!strcmp(var, "core.compression")) {
356                 int level = git_config_int(var, value);
357                 if (level == -1)
358                         level = Z_DEFAULT_COMPRESSION;
359                 else if (level < 0 || level > Z_BEST_COMPRESSION)
360                         die("bad zlib compression level %d", level);
361                 core_compression_level = level;
362                 core_compression_seen = 1;
363                 if (!zlib_compression_seen)
364                         zlib_compression_level = level;
365                 return 0;
366         }
368         if (!strcmp(var, "core.packedgitwindowsize")) {
369                 int pgsz_x2 = getpagesize() * 2;
370                 packed_git_window_size = git_config_int(var, value);
372                 /* This value must be multiple of (pagesize * 2) */
373                 packed_git_window_size /= pgsz_x2;
374                 if (packed_git_window_size < 1)
375                         packed_git_window_size = 1;
376                 packed_git_window_size *= pgsz_x2;
377                 return 0;
378         }
380         if (!strcmp(var, "core.packedgitlimit")) {
381                 packed_git_limit = git_config_int(var, value);
382                 return 0;
383         }
385         if (!strcmp(var, "core.deltabasecachelimit")) {
386                 delta_base_cache_limit = git_config_int(var, value);
387                 return 0;
388         }
390         if (!strcmp(var, "core.autocrlf")) {
391                 if (value && !strcasecmp(value, "input")) {
392                         auto_crlf = -1;
393                         return 0;
394                 }
395                 auto_crlf = git_config_bool(var, value);
396                 return 0;
397         }
399         if (!strcmp(var, "user.name")) {
400                 strlcpy(git_default_name, value, sizeof(git_default_name));
401                 return 0;
402         }
404         if (!strcmp(var, "user.email")) {
405                 strlcpy(git_default_email, value, sizeof(git_default_email));
406                 return 0;
407         }
409         if (!strcmp(var, "i18n.commitencoding")) {
410                 git_commit_encoding = xstrdup(value);
411                 return 0;
412         }
414         if (!strcmp(var, "i18n.logoutputencoding")) {
415                 git_log_output_encoding = xstrdup(value);
416                 return 0;
417         }
420         if (!strcmp(var, "pager.color") || !strcmp(var, "color.pager")) {
421                 pager_use_color = git_config_bool(var,value);
422                 return 0;
423         }
425         if (!strcmp(var, "core.pager")) {
426                 pager_program = xstrdup(value);
427                 return 0;
428         }
430         if (!strcmp(var, "core.editor")) {
431                 editor_program = xstrdup(value);
432                 return 0;
433         }
435         if (!strcmp(var, "core.excludesfile")) {
436                 if (!value)
437                         die("core.excludesfile without value");
438                 excludes_file = xstrdup(value);
439                 return 0;
440         }
442         /* Add other config variables here and to Documentation/config.txt. */
443         return 0;
446 int git_config_from_file(config_fn_t fn, const char *filename)
448         int ret;
449         FILE *f = fopen(filename, "r");
451         ret = -1;
452         if (f) {
453                 config_file = f;
454                 config_file_name = filename;
455                 config_linenr = 1;
456                 ret = git_parse_file(fn);
457                 fclose(f);
458                 config_file_name = NULL;
459         }
460         return ret;
463 const char *git_etc_gitconfig(void)
465         static const char *system_wide;
466         if (!system_wide) {
467                 system_wide = ETC_GITCONFIG;
468                 if (!is_absolute_path(system_wide)) {
469                         /* interpret path relative to exec-dir */
470                         const char *exec_path = git_exec_path();
471                         system_wide = prefix_path(exec_path, strlen(exec_path),
472                                                 system_wide);
473                 }
474         }
475         return system_wide;
478 int git_config(config_fn_t fn)
480         int ret = 0;
481         char *repo_config = NULL;
482         const char *home = NULL, *filename;
484         /* $GIT_CONFIG makes git read _only_ the given config file,
485          * $GIT_CONFIG_LOCAL will make it process it in addition to the
486          * global config file, the same way it would the per-repository
487          * config file otherwise. */
488         filename = getenv(CONFIG_ENVIRONMENT);
489         if (!filename) {
490                 if (!access(git_etc_gitconfig(), R_OK))
491                         ret += git_config_from_file(fn, git_etc_gitconfig());
492                 home = getenv("HOME");
493                 filename = getenv(CONFIG_LOCAL_ENVIRONMENT);
494                 if (!filename)
495                         filename = repo_config = xstrdup(git_path("config"));
496         }
498         if (home) {
499                 char *user_config = xstrdup(mkpath("%s/.gitconfig", home));
500                 if (!access(user_config, R_OK))
501                         ret = git_config_from_file(fn, user_config);
502                 free(user_config);
503         }
505         ret += git_config_from_file(fn, filename);
506         free(repo_config);
507         return ret;
511  * Find all the stuff for git_config_set() below.
512  */
514 #define MAX_MATCHES 512
516 static struct {
517         int baselen;
518         char* key;
519         int do_not_match;
520         regex_t* value_regex;
521         int multi_replace;
522         size_t offset[MAX_MATCHES];
523         enum { START, SECTION_SEEN, SECTION_END_SEEN, KEY_SEEN } state;
524         int seen;
525 } store;
527 static int matches(const char* key, const char* value)
529         return !strcmp(key, store.key) &&
530                 (store.value_regex == NULL ||
531                  (store.do_not_match ^
532                   !regexec(store.value_regex, value, 0, NULL, 0)));
535 static int store_aux(const char* key, const char* value)
537         const char *ep;
538         size_t section_len;
540         switch (store.state) {
541         case KEY_SEEN:
542                 if (matches(key, value)) {
543                         if (store.seen == 1 && store.multi_replace == 0) {
544                                 fprintf(stderr,
545                                         "Warning: %s has multiple values\n",
546                                         key);
547                         } else if (store.seen >= MAX_MATCHES) {
548                                 fprintf(stderr, "Too many matches\n");
549                                 return 1;
550                         }
552                         store.offset[store.seen] = ftell(config_file);
553                         store.seen++;
554                 }
555                 break;
556         case SECTION_SEEN:
557                 /*
558                  * What we are looking for is in store.key (both
559                  * section and var), and its section part is baselen
560                  * long.  We found key (again, both section and var).
561                  * We would want to know if this key is in the same
562                  * section as what we are looking for.  We already
563                  * know we are in the same section as what should
564                  * hold store.key.
565                  */
566                 ep = strrchr(key, '.');
567                 section_len = ep - key;
569                 if ((section_len != store.baselen) ||
570                     memcmp(key, store.key, section_len+1)) {
571                         store.state = SECTION_END_SEEN;
572                         break;
573                 }
575                 /*
576                  * Do not increment matches: this is no match, but we
577                  * just made sure we are in the desired section.
578                  */
579                 store.offset[store.seen] = ftell(config_file);
580                 /* fallthru */
581         case SECTION_END_SEEN:
582         case START:
583                 if (matches(key, value)) {
584                         store.offset[store.seen] = ftell(config_file);
585                         store.state = KEY_SEEN;
586                         store.seen++;
587                 } else {
588                         if (strrchr(key, '.') - key == store.baselen &&
589                               !strncmp(key, store.key, store.baselen)) {
590                                         store.state = SECTION_SEEN;
591                                         store.offset[store.seen] = ftell(config_file);
592                         }
593                 }
594         }
595         return 0;
598 static int write_error(void)
600         fprintf(stderr, "Failed to write new configuration file\n");
602         /* Same error code as "failed to rename". */
603         return 4;
606 static int store_write_section(int fd, const char* key)
608         const char *dot = strchr(key, '.');
609         int len1 = store.baselen, len2 = -1;
611         dot = strchr(key, '.');
612         if (dot) {
613                 int dotlen = dot - key;
614                 if (dotlen < len1) {
615                         len2 = len1 - dotlen - 1;
616                         len1 = dotlen;
617                 }
618         }
620         if (write_in_full(fd, "[", 1) != 1 ||
621             write_in_full(fd, key, len1) != len1)
622                 return 0;
623         if (len2 >= 0) {
624                 if (write_in_full(fd, " \"", 2) != 2)
625                         return 0;
626                 while (--len2 >= 0) {
627                         unsigned char c = *++dot;
628                         if (c == '"')
629                                 if (write_in_full(fd, "\\", 1) != 1)
630                                         return 0;
631                         if (write_in_full(fd, &c, 1) != 1)
632                                 return 0;
633                 }
634                 if (write_in_full(fd, "\"", 1) != 1)
635                         return 0;
636         }
637         if (write_in_full(fd, "]\n", 2) != 2)
638                 return 0;
640         return 1;
643 static int store_write_pair(int fd, const char* key, const char* value)
645         int i;
646         int length = strlen(key+store.baselen+1);
647         int quote = 0;
649         /* Check to see if the value needs to be quoted. */
650         if (value[0] == ' ')
651                 quote = 1;
652         for (i = 0; value[i]; i++)
653                 if (value[i] == ';' || value[i] == '#')
654                         quote = 1;
655         if (value[i-1] == ' ')
656                 quote = 1;
658         if (write_in_full(fd, "\t", 1) != 1 ||
659             write_in_full(fd, key+store.baselen+1, length) != length ||
660             write_in_full(fd, " = ", 3) != 3)
661                 return 0;
662         if (quote && write_in_full(fd, "\"", 1) != 1)
663                 return 0;
664         for (i = 0; value[i]; i++)
665                 switch (value[i]) {
666                 case '\n':
667                         if (write_in_full(fd, "\\n", 2) != 2)
668                                 return 0;
669                         break;
670                 case '\t':
671                         if (write_in_full(fd, "\\t", 2) != 2)
672                                 return 0;
673                         break;
674                 case '"':
675                 case '\\':
676                         if (write_in_full(fd, "\\", 1) != 1)
677                                 return 0;
678                 default:
679                         if (write_in_full(fd, value+i, 1) != 1)
680                                 return 0;
681                         break;
682                 }
683         if (quote && write_in_full(fd, "\"", 1) != 1)
684                 return 0;
685         if (write_in_full(fd, "\n", 1) != 1)
686                 return 0;
687         return 1;
690 static ssize_t find_beginning_of_line(const char* contents, size_t size,
691         size_t offset_, int* found_bracket)
693         size_t equal_offset = size, bracket_offset = size;
694         ssize_t offset;
696         for (offset = offset_-2; offset > 0
697                         && contents[offset] != '\n'; offset--)
698                 switch (contents[offset]) {
699                         case '=': equal_offset = offset; break;
700                         case ']': bracket_offset = offset; break;
701                 }
702         if (bracket_offset < equal_offset) {
703                 *found_bracket = 1;
704                 offset = bracket_offset+1;
705         } else
706                 offset++;
708         return offset;
711 int git_config_set(const char* key, const char* value)
713         return git_config_set_multivar(key, value, NULL, 0);
717  * If value==NULL, unset in (remove from) config,
718  * if value_regex!=NULL, disregard key/value pairs where value does not match.
719  * if multi_replace==0, nothing, or only one matching key/value is replaced,
720  *     else all matching key/values (regardless how many) are removed,
721  *     before the new pair is written.
723  * Returns 0 on success.
725  * This function does this:
727  * - it locks the config file by creating ".git/config.lock"
729  * - it then parses the config using store_aux() as validator to find
730  *   the position on the key/value pair to replace. If it is to be unset,
731  *   it must be found exactly once.
733  * - the config file is mmap()ed and the part before the match (if any) is
734  *   written to the lock file, then the changed part and the rest.
736  * - the config file is removed and the lock file rename()d to it.
738  */
739 int git_config_set_multivar(const char* key, const char* value,
740         const char* value_regex, int multi_replace)
742         int i, dot;
743         int fd = -1, in_fd;
744         int ret;
745         char* config_filename;
746         struct lock_file *lock = NULL;
747         const char* last_dot = strrchr(key, '.');
749         config_filename = getenv(CONFIG_ENVIRONMENT);
750         if (!config_filename) {
751                 config_filename = getenv(CONFIG_LOCAL_ENVIRONMENT);
752                 if (!config_filename)
753                         config_filename  = git_path("config");
754         }
755         config_filename = xstrdup(config_filename);
757         /*
758          * Since "key" actually contains the section name and the real
759          * key name separated by a dot, we have to know where the dot is.
760          */
762         if (last_dot == NULL) {
763                 fprintf(stderr, "key does not contain a section: %s\n", key);
764                 ret = 2;
765                 goto out_free;
766         }
767         store.baselen = last_dot - key;
769         store.multi_replace = multi_replace;
771         /*
772          * Validate the key and while at it, lower case it for matching.
773          */
774         store.key = xmalloc(strlen(key) + 1);
775         dot = 0;
776         for (i = 0; key[i]; i++) {
777                 unsigned char c = key[i];
778                 if (c == '.')
779                         dot = 1;
780                 /* Leave the extended basename untouched.. */
781                 if (!dot || i > store.baselen) {
782                         if (!iskeychar(c) || (i == store.baselen+1 && !isalpha(c))) {
783                                 fprintf(stderr, "invalid key: %s\n", key);
784                                 free(store.key);
785                                 ret = 1;
786                                 goto out_free;
787                         }
788                         c = tolower(c);
789                 } else if (c == '\n') {
790                         fprintf(stderr, "invalid key (newline): %s\n", key);
791                         free(store.key);
792                         ret = 1;
793                         goto out_free;
794                 }
795                 store.key[i] = c;
796         }
797         store.key[i] = 0;
799         /*
800          * The lock serves a purpose in addition to locking: the new
801          * contents of .git/config will be written into it.
802          */
803         lock = xcalloc(sizeof(struct lock_file), 1);
804         fd = hold_lock_file_for_update(lock, config_filename, 0);
805         if (fd < 0) {
806                 fprintf(stderr, "could not lock config file\n");
807                 free(store.key);
808                 ret = -1;
809                 goto out_free;
810         }
812         /*
813          * If .git/config does not exist yet, write a minimal version.
814          */
815         in_fd = open(config_filename, O_RDONLY);
816         if ( in_fd < 0 ) {
817                 free(store.key);
819                 if ( ENOENT != errno ) {
820                         error("opening %s: %s", config_filename,
821                               strerror(errno));
822                         ret = 3; /* same as "invalid config file" */
823                         goto out_free;
824                 }
825                 /* if nothing to unset, error out */
826                 if (value == NULL) {
827                         ret = 5;
828                         goto out_free;
829                 }
831                 store.key = (char*)key;
832                 if (!store_write_section(fd, key) ||
833                     !store_write_pair(fd, key, value))
834                         goto write_err_out;
835         } else {
836                 struct stat st;
837                 char* contents;
838                 size_t contents_sz, copy_begin, copy_end;
839                 int i, new_line = 0;
841                 if (value_regex == NULL)
842                         store.value_regex = NULL;
843                 else {
844                         if (value_regex[0] == '!') {
845                                 store.do_not_match = 1;
846                                 value_regex++;
847                         } else
848                                 store.do_not_match = 0;
850                         store.value_regex = (regex_t*)xmalloc(sizeof(regex_t));
851                         if (regcomp(store.value_regex, value_regex,
852                                         REG_EXTENDED)) {
853                                 fprintf(stderr, "Invalid pattern: %s\n",
854                                         value_regex);
855                                 free(store.value_regex);
856                                 ret = 6;
857                                 goto out_free;
858                         }
859                 }
861                 store.offset[0] = 0;
862                 store.state = START;
863                 store.seen = 0;
865                 /*
866                  * After this, store.offset will contain the *end* offset
867                  * of the last match, or remain at 0 if no match was found.
868                  * As a side effect, we make sure to transform only a valid
869                  * existing config file.
870                  */
871                 if (git_config_from_file(store_aux, config_filename)) {
872                         fprintf(stderr, "invalid config file\n");
873                         free(store.key);
874                         if (store.value_regex != NULL) {
875                                 regfree(store.value_regex);
876                                 free(store.value_regex);
877                         }
878                         ret = 3;
879                         goto out_free;
880                 }
882                 free(store.key);
883                 if (store.value_regex != NULL) {
884                         regfree(store.value_regex);
885                         free(store.value_regex);
886                 }
888                 /* if nothing to unset, or too many matches, error out */
889                 if ((store.seen == 0 && value == NULL) ||
890                                 (store.seen > 1 && multi_replace == 0)) {
891                         ret = 5;
892                         goto out_free;
893                 }
895                 fstat(in_fd, &st);
896                 contents_sz = xsize_t(st.st_size);
897                 contents = xmmap(NULL, contents_sz, PROT_READ,
898                         MAP_PRIVATE, in_fd, 0);
899                 close(in_fd);
901                 if (store.seen == 0)
902                         store.seen = 1;
904                 for (i = 0, copy_begin = 0; i < store.seen; i++) {
905                         if (store.offset[i] == 0) {
906                                 store.offset[i] = copy_end = contents_sz;
907                         } else if (store.state != KEY_SEEN) {
908                                 copy_end = store.offset[i];
909                         } else
910                                 copy_end = find_beginning_of_line(
911                                         contents, contents_sz,
912                                         store.offset[i]-2, &new_line);
914                         /* write the first part of the config */
915                         if (copy_end > copy_begin) {
916                                 if (write_in_full(fd, contents + copy_begin,
917                                                   copy_end - copy_begin) <
918                                     copy_end - copy_begin)
919                                         goto write_err_out;
920                                 if (new_line &&
921                                     write_in_full(fd, "\n", 1) != 1)
922                                         goto write_err_out;
923                         }
924                         copy_begin = store.offset[i];
925                 }
927                 /* write the pair (value == NULL means unset) */
928                 if (value != NULL) {
929                         if (store.state == START) {
930                                 if (!store_write_section(fd, key))
931                                         goto write_err_out;
932                         }
933                         if (!store_write_pair(fd, key, value))
934                                 goto write_err_out;
935                 }
937                 /* write the rest of the config */
938                 if (copy_begin < contents_sz)
939                         if (write_in_full(fd, contents + copy_begin,
940                                           contents_sz - copy_begin) <
941                             contents_sz - copy_begin)
942                                 goto write_err_out;
944                 munmap(contents, contents_sz);
945         }
947         if (close(fd) || commit_lock_file(lock) < 0) {
948                 fprintf(stderr, "Cannot commit config file!\n");
949                 ret = 4;
950                 goto out_free;
951         }
953         /* fd is closed, so don't try to close it below. */
954         fd = -1;
955         /*
956          * lock is committed, so don't try to roll it back below.
957          * NOTE: Since lockfile.c keeps a linked list of all created
958          * lock_file structures, it isn't safe to free(lock).  It's
959          * better to just leave it hanging around.
960          */
961         lock = NULL;
962         ret = 0;
964 out_free:
965         if (0 <= fd)
966                 close(fd);
967         if (lock)
968                 rollback_lock_file(lock);
969         free(config_filename);
970         return ret;
972 write_err_out:
973         ret = write_error();
974         goto out_free;
978 static int section_name_match (const char *buf, const char *name)
980         int i = 0, j = 0, dot = 0;
981         for (; buf[i] && buf[i] != ']'; i++) {
982                 if (!dot && isspace(buf[i])) {
983                         dot = 1;
984                         if (name[j++] != '.')
985                                 break;
986                         for (i++; isspace(buf[i]); i++)
987                                 ; /* do nothing */
988                         if (buf[i] != '"')
989                                 break;
990                         continue;
991                 }
992                 if (buf[i] == '\\' && dot)
993                         i++;
994                 else if (buf[i] == '"' && dot) {
995                         for (i++; isspace(buf[i]); i++)
996                                 ; /* do_nothing */
997                         break;
998                 }
999                 if (buf[i] != name[j++])
1000                         break;
1001         }
1002         return (buf[i] == ']' && name[j] == 0);
1005 /* if new_name == NULL, the section is removed instead */
1006 int git_config_rename_section(const char *old_name, const char *new_name)
1008         int ret = 0, remove = 0;
1009         char *config_filename;
1010         struct lock_file *lock = xcalloc(sizeof(struct lock_file), 1);
1011         int out_fd;
1012         char buf[1024];
1014         config_filename = getenv(CONFIG_ENVIRONMENT);
1015         if (!config_filename) {
1016                 config_filename = getenv(CONFIG_LOCAL_ENVIRONMENT);
1017                 if (!config_filename)
1018                         config_filename  = git_path("config");
1019         }
1020         config_filename = xstrdup(config_filename);
1021         out_fd = hold_lock_file_for_update(lock, config_filename, 0);
1022         if (out_fd < 0) {
1023                 ret = error("Could not lock config file!");
1024                 goto out;
1025         }
1027         if (!(config_file = fopen(config_filename, "rb"))) {
1028                 /* no config file means nothing to rename, no error */
1029                 goto unlock_and_out;
1030         }
1032         while (fgets(buf, sizeof(buf), config_file)) {
1033                 int i;
1034                 int length;
1035                 for (i = 0; buf[i] && isspace(buf[i]); i++)
1036                         ; /* do nothing */
1037                 if (buf[i] == '[') {
1038                         /* it's a section */
1039                         if (section_name_match (&buf[i+1], old_name)) {
1040                                 ret++;
1041                                 if (new_name == NULL) {
1042                                         remove = 1;
1043                                         continue;
1044                                 }
1045                                 store.baselen = strlen(new_name);
1046                                 if (!store_write_section(out_fd, new_name)) {
1047                                         ret = write_error();
1048                                         goto out;
1049                                 }
1050                                 continue;
1051                         }
1052                         remove = 0;
1053                 }
1054                 if (remove)
1055                         continue;
1056                 length = strlen(buf);
1057                 if (write_in_full(out_fd, buf, length) != length) {
1058                         ret = write_error();
1059                         goto out;
1060                 }
1061         }
1062         fclose(config_file);
1063  unlock_and_out:
1064         if (close(out_fd) || commit_lock_file(lock) < 0)
1065                         ret = error("Cannot commit config file!");
1066  out:
1067         free(config_filename);
1068         return ret;