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 "exec_cmd.h"
  10 #include "strbuf.h"
  11
  12 #define MAXNAME (256)
  13
  14 static FILE *config_file;
  15 static const char *config_file_name;
  16 static int config_linenr;
  17 static int config_file_eof;
  18 static int zlib_compression_seen;
  19
  20 const char *config_exclusive_filename = NULL;
  21
  22 struct config_item
  23 {
  24         struct config_item *next;
  25         char *name;
  26         char *value;
  27 };
  28 static struct config_item *config_parameters;
  29 static struct config_item **config_parameters_tail = &config_parameters;
  30
  31 static void lowercase(char *p)
  32 {
  33         for (; *p; p++)
  34                 *p = tolower(*p);
  35 }
  36
  37 int git_config_parse_parameter(const char *text)
  38 {
  39         struct config_item *ct;
  40         struct strbuf tmp = STRBUF_INIT;
  41         struct strbuf **pair;
  42         strbuf_addstr(&tmp, text);
  43         pair = strbuf_split(&tmp, '=');
  44         if (pair[0]->len && pair[0]->buf[pair[0]->len - 1] == '=')
  45                 strbuf_setlen(pair[0], pair[0]->len - 1);
  46         strbuf_trim(pair[0]);
  47         if (!pair[0]->len) {
  48                 strbuf_list_free(pair);
  49                 return -1;
  50         }
  51         ct = xcalloc(1, sizeof(struct config_item));
  52         ct->name = strbuf_detach(pair[0], NULL);
  53         if (pair[1]) {
  54                 strbuf_trim(pair[1]);
  55                 ct->value = strbuf_detach(pair[1], NULL);
  56         }
  57         strbuf_list_free(pair);
  58         lowercase(ct->name);
  59         *config_parameters_tail = ct;
  60         config_parameters_tail = &ct->next;
  61         return 0;
  62 }
  63
  64 static int get_next_char(void)
  65 {
  66         int c;
  67         FILE *f;
  68
  69         c = '\n';
  70         if ((f = config_file) != NULL) {
  71                 c = fgetc(f);
  72                 if (c == '\r') {
  73                         /* DOS like systems */
  74                         c = fgetc(f);
  75                         if (c != '\n') {
  76                                 ungetc(c, f);
  77                                 c = '\r';
  78                         }
  79                 }
  80                 if (c == '\n')
  81                         config_linenr++;
  82                 if (c == EOF) {
  83                         config_file_eof = 1;
  84                         c = '\n';
  85                 }
  86         }
  87         return c;
  88 }
  89
  90 static char *parse_value(void)
  91 {
  92         static char value[1024];
  93         int quote = 0, comment = 0, len = 0, space = 0;
  94
  95         for (;;) {
  96                 int c = get_next_char();
  97                 if (len >= sizeof(value) - 1)
  98                         return NULL;
  99                 if (c == '\n') {
 100                         if (quote)
 101                                 return NULL;
 102                         value[len] = 0;
 103                         return value;
 104                 }
 105                 if (comment)
 106                         continue;
 107                 if (isspace(c) && !quote) {
 108                         if (len)
 109                                 space++;
 110                         continue;
 111                 }
 112                 if (!quote) {
 113                         if (c == ';' || c == '#') {
 114                                 comment = 1;
 115                                 continue;
 116                         }
 117                 }
 118                 for (; space; space--)
 119                         value[len++] = ' ';
 120                 if (c == '\\') {
 121                         c = get_next_char();
 122                         switch (c) {
 123                         case '\n':
 124                                 continue;
 125                         case 't':
 126                                 c = '\t';
 127                                 break;
 128                         case 'b':
 129                                 c = '\b';
 130                                 break;
 131                         case 'n':
 132                                 c = '\n';
 133                                 break;
 134                         /* Some characters escape as themselves */
 135                         case '\\': case '"':
 136                                 break;
 137                         /* Reject unknown escape sequences */
 138                         default:
 139                                 return NULL;
 140                         }
 141                         value[len++] = c;
 142                         continue;
 143                 }
 144                 if (c == '"') {
 145                         quote = 1-quote;
 146                         continue;
 147                 }
 148                 value[len++] = c;
 149         }
 150 }
 151
 152 static inline int iskeychar(int c)
 153 {
 154         return isalnum(c) || c == '-';
 155 }
 156
 157 static int get_value(config_fn_t fn, void *data, char *name, unsigned int len)
 158 {
 159         int c;
 160         char *value;
 161
 162         /* Get the full name */
 163         for (;;) {
 164                 c = get_next_char();
 165                 if (config_file_eof)
 166                         break;
 167                 if (!iskeychar(c))
 168                         break;
 169                 name[len++] = tolower(c);
 170                 if (len >= MAXNAME)
 171                         return -1;
 172         }
 173         name[len] = 0;
 174         while (c == ' ' || c == '\t')
 175                 c = get_next_char();
 176
 177         value = NULL;
 178         if (c != '\n') {
 179                 if (c != '=')
 180                         return -1;
 181                 value = parse_value();
 182                 if (!value)
 183                         return -1;
 184         }
 185         return fn(name, value, data);
 186 }
 187
 188 static int get_extended_base_var(char *name, int baselen, int c)
 189 {
 190         do {
 191                 if (c == '\n')
 192                         return -1;
 193                 c = get_next_char();
 194         } while (isspace(c));
 195
 196         /* We require the format to be '[base "extension"]' */
 197         if (c != '"')
 198                 return -1;
 199         name[baselen++] = '.';
 200
 201         for (;;) {
 202                 int c = get_next_char();
 203                 if (c == '\n')
 204                         return -1;
 205                 if (c == '"')
 206                         break;
 207                 if (c == '\\') {
 208                         c = get_next_char();
 209                         if (c == '\n')
 210                                 return -1;
 211                 }
 212                 name[baselen++] = c;
 213                 if (baselen > MAXNAME / 2)
 214                         return -1;
 215         }
 216
 217         /* Final ']' */
 218         if (get_next_char() != ']')
 219                 return -1;
 220         return baselen;
 221 }
 222
 223 static int get_base_var(char *name)
 224 {
 225         int baselen = 0;
 226
 227         for (;;) {
 228                 int c = get_next_char();
 229                 if (config_file_eof)
 230                         return -1;
 231                 if (c == ']')
 232                         return baselen;
 233                 if (isspace(c))
 234                         return get_extended_base_var(name, baselen, c);
 235                 if (!iskeychar(c) && c != '.')
 236                         return -1;
 237                 if (baselen > MAXNAME / 2)
 238                         return -1;
 239                 name[baselen++] = tolower(c);
 240         }
 241 }
 242
 243 static int git_parse_file(config_fn_t fn, void *data)
 244 {
 245         int comment = 0;
 246         int baselen = 0;
 247         static char var[MAXNAME];
 248
 249         /* U+FEFF Byte Order Mark in UTF8 */
 250         static const unsigned char *utf8_bom = (unsigned char *) "\xef\xbb\xbf";
 251         const unsigned char *bomptr = utf8_bom;
 252
 253         for (;;) {
 254                 int c = get_next_char();
 255                 if (bomptr && *bomptr) {
 256                         /* We are at the file beginning; skip UTF8-encoded BOM
 257                          * if present. Sane editors won't put this in on their
 258                          * own, but e.g. Windows Notepad will do it happily. */
 259                         if ((unsigned char) c == *bomptr) {
 260                                 bomptr++;
 261                                 continue;
 262                         } else {
 263                                 /* Do not tolerate partial BOM. */
 264                                 if (bomptr != utf8_bom)
 265                                         break;
 266                                 /* No BOM at file beginning. Cool. */
 267                                 bomptr = NULL;
 268                         }
 269                 }
 270                 if (c == '\n') {
 271                         if (config_file_eof)
 272                                 return 0;
 273                         comment = 0;
 274                         continue;
 275                 }
 276                 if (comment || isspace(c))
 277                         continue;
 278                 if (c == '#' || c == ';') {
 279                         comment = 1;
 280                         continue;
 281                 }
 282                 if (c == '[') {
 283                         baselen = get_base_var(var);
 284                         if (baselen <= 0)
 285                                 break;
 286                         var[baselen++] = '.';
 287                         var[baselen] = 0;
 288                         continue;
 289                 }
 290                 if (!isalpha(c))
 291                         break;
 292                 var[baselen] = tolower(c);
 293                 if (get_value(fn, data, var, baselen+1) < 0)
 294                         break;
 295         }
 296         die("bad config file line %d in %s", config_linenr, config_file_name);
 297 }
 298
 299 static int parse_unit_factor(const char *end, unsigned long *val)
 300 {
 301         if (!*end)
 302                 return 1;
 303         else if (!strcasecmp(end, "k")) {
 304                 *val *= 1024;
 305                 return 1;
 306         }
 307         else if (!strcasecmp(end, "m")) {
 308                 *val *= 1024 * 1024;
 309                 return 1;
 310         }
 311         else if (!strcasecmp(end, "g")) {
 312                 *val *= 1024 * 1024 * 1024;
 313                 return 1;
 314         }
 315         return 0;
 316 }
 317
 318 static int git_parse_long(const char *value, long *ret)
 319 {
 320         if (value && *value) {
 321                 char *end;
 322                 long val = strtol(value, &end, 0);
 323                 unsigned long factor = 1;
 324                 if (!parse_unit_factor(end, &factor))
 325                         return 0;
 326                 *ret = val * factor;
 327                 return 1;
 328         }
 329         return 0;
 330 }
 331
 332 int git_parse_ulong(const char *value, unsigned long *ret)
 333 {
 334         if (value && *value) {
 335                 char *end;
 336                 unsigned long val = strtoul(value, &end, 0);
 337                 if (!parse_unit_factor(end, &val))
 338                         return 0;
 339                 *ret = val;
 340                 return 1;
 341         }
 342         return 0;
 343 }
 344
 345 static void die_bad_config(const char *name)
 346 {
 347         if (config_file_name)
 348                 die("bad config value for '%s' in %s", name, config_file_name);
 349         die("bad config value for '%s'", name);
 350 }
 351
 352 int git_config_int(const char *name, const char *value)
 353 {
 354         long ret = 0;
 355         if (!git_parse_long(value, &ret))
 356                 die_bad_config(name);
 357         return ret;
 358 }
 359
 360 unsigned long git_config_ulong(const char *name, const char *value)
 361 {
 362         unsigned long ret;
 363         if (!git_parse_ulong(value, &ret))
 364                 die_bad_config(name);
 365         return ret;
 366 }
 367
 368 int git_config_maybe_bool(const char *name, const char *value)
 369 {
 370         if (!value)
 371                 return 1;
 372         if (!*value)
 373                 return 0;
 374         if (!strcasecmp(value, "true")
 375             || !strcasecmp(value, "yes")
 376             || !strcasecmp(value, "on"))
 377                 return 1;
 378         if (!strcasecmp(value, "false")
 379             || !strcasecmp(value, "no")
 380             || !strcasecmp(value, "off"))
 381                 return 0;
 382         return -1;
 383 }
 384
 385 int git_config_bool_or_int(const char *name, const char *value, int *is_bool)
 386 {
 387         int v = git_config_maybe_bool(name, value);
 388         if (0 <= v) {
 389                 *is_bool = 1;
 390                 return v;
 391         }
 392         *is_bool = 0;
 393         return git_config_int(name, value);
 394 }
 395
 396 int git_config_bool(const char *name, const char *value)
 397 {
 398         int discard;
 399         return !!git_config_bool_or_int(name, value, &discard);
 400 }
 401
 402 int git_config_string(const char **dest, const char *var, const char *value)
 403 {
 404         if (!value)
 405                 return config_error_nonbool(var);
 406         *dest = xstrdup(value);
 407         return 0;
 408 }
 409
 410 int git_config_pathname(const char **dest, const char *var, const char *value)
 411 {
 412         if (!value)
 413                 return config_error_nonbool(var);
 414         *dest = expand_user_path(value);
 415         if (!*dest)
 416                 die("Failed to expand user dir in: '%s'", value);
 417         return 0;
 418 }
 419
 420 static int git_default_core_config(const char *var, const char *value)
 421 {
 422         /* This needs a better name */
 423         if (!strcmp(var, "core.filemode")) {
 424                 trust_executable_bit = git_config_bool(var, value);
 425                 return 0;
 426         }
 427         if (!strcmp(var, "core.trustctime")) {
 428                 trust_ctime = git_config_bool(var, value);
 429                 return 0;
 430         }
 431
 432         if (!strcmp(var, "core.quotepath")) {
 433                 quote_path_fully = git_config_bool(var, value);
 434                 return 0;
 435         }
 436
 437         if (!strcmp(var, "core.symlinks")) {
 438                 has_symlinks = git_config_bool(var, value);
 439                 return 0;
 440         }
 441
 442         if (!strcmp(var, "core.ignorecase")) {
 443                 ignore_case = git_config_bool(var, value);
 444                 return 0;
 445         }
 446
 447         if (!strcmp(var, "core.bare")) {
 448                 is_bare_repository_cfg = git_config_bool(var, value);
 449                 return 0;
 450         }
 451
 452         if (!strcmp(var, "core.ignorestat")) {
 453                 assume_unchanged = git_config_bool(var, value);
 454                 return 0;
 455         }
 456
 457         if (!strcmp(var, "core.prefersymlinkrefs")) {
 458                 prefer_symlink_refs = git_config_bool(var, value);
 459                 return 0;
 460         }
 461
 462         if (!strcmp(var, "core.logallrefupdates")) {
 463                 log_all_ref_updates = git_config_bool(var, value);
 464                 return 0;
 465         }
 466
 467         if (!strcmp(var, "core.warnambiguousrefs")) {
 468                 warn_ambiguous_refs = git_config_bool(var, value);
 469                 return 0;
 470         }
 471
 472         if (!strcmp(var, "core.loosecompression")) {
 473                 int level = git_config_int(var, value);
 474                 if (level == -1)
 475                         level = Z_DEFAULT_COMPRESSION;
 476                 else if (level < 0 || level > Z_BEST_COMPRESSION)
 477                         die("bad zlib compression level %d", level);
 478                 zlib_compression_level = level;
 479                 zlib_compression_seen = 1;
 480                 return 0;
 481         }
 482
 483         if (!strcmp(var, "core.compression")) {
 484                 int level = git_config_int(var, value);
 485                 if (level == -1)
 486                         level = Z_DEFAULT_COMPRESSION;
 487                 else if (level < 0 || level > Z_BEST_COMPRESSION)
 488                         die("bad zlib compression level %d", level);
 489                 core_compression_level = level;
 490                 core_compression_seen = 1;
 491                 if (!zlib_compression_seen)
 492                         zlib_compression_level = level;
 493                 return 0;
 494         }
 495
 496         if (!strcmp(var, "core.packedgitwindowsize")) {
 497                 int pgsz_x2 = getpagesize() * 2;
 498                 packed_git_window_size = git_config_int(var, value);
 499
 500                 /* This value must be multiple of (pagesize * 2) */
 501                 packed_git_window_size /= pgsz_x2;
 502                 if (packed_git_window_size < 1)
 503                         packed_git_window_size = 1;
 504                 packed_git_window_size *= pgsz_x2;
 505                 return 0;
 506         }
 507
 508         if (!strcmp(var, "core.packedgitlimit")) {
 509                 packed_git_limit = git_config_int(var, value);
 510                 return 0;
 511         }
 512
 513         if (!strcmp(var, "core.deltabasecachelimit")) {
 514                 delta_base_cache_limit = git_config_int(var, value);
 515                 return 0;
 516         }
 517
 518         if (!strcmp(var, "core.autocrlf")) {
 519                 if (value && !strcasecmp(value, "input")) {
 520                         auto_crlf = -1;
 521                         return 0;
 522                 }
 523                 auto_crlf = git_config_bool(var, value);
 524                 return 0;
 525         }
 526
 527         if (!strcmp(var, "core.safecrlf")) {
 528                 if (value && !strcasecmp(value, "warn")) {
 529                         safe_crlf = SAFE_CRLF_WARN;
 530                         return 0;
 531                 }
 532                 safe_crlf = git_config_bool(var, value);
 533                 return 0;
 534         }
 535
 536         if (!strcmp(var, "core.notesref")) {
 537                 notes_ref_name = xstrdup(value);
 538                 return 0;
 539         }
 540
 541         if (!strcmp(var, "core.pager"))
 542                 return git_config_string(&pager_program, var, value);
 543
 544         if (!strcmp(var, "core.editor"))
 545                 return git_config_string(&editor_program, var, value);
 546
 547         if (!strcmp(var, "core.excludesfile"))
 548                 return git_config_pathname(&excludes_file, var, value);
 549
 550         if (!strcmp(var, "core.whitespace")) {
 551                 if (!value)
 552                         return config_error_nonbool(var);
 553                 whitespace_rule_cfg = parse_whitespace_rule(value);
 554                 return 0;
 555         }
 556
 557         if (!strcmp(var, "core.fsyncobjectfiles")) {
 558                 fsync_object_files = git_config_bool(var, value);
 559                 return 0;
 560         }
 561
 562         if (!strcmp(var, "core.preloadindex")) {
 563                 core_preload_index = git_config_bool(var, value);
 564                 return 0;
 565         }
 566
 567         if (!strcmp(var, "core.createobject")) {
 568                 if (!strcmp(value, "rename"))
 569                         object_creation_mode = OBJECT_CREATION_USES_RENAMES;
 570                 else if (!strcmp(value, "link"))
 571                         object_creation_mode = OBJECT_CREATION_USES_HARDLINKS;
 572                 else
 573                         die("Invalid mode for object creation: %s", value);
 574                 return 0;
 575         }
 576
 577         if (!strcmp(var, "core.sparsecheckout")) {
 578                 core_apply_sparse_checkout = git_config_bool(var, value);
 579                 return 0;
 580         }
 581
 582         if (!strcmp(var, "core.hidedotfiles")) {
 583                 if (value && !strcasecmp(value, "dotgitonly")) {
 584                         hide_dotfiles = HIDE_DOTFILES_DOTGITONLY;
 585                         return 0;
 586                 }
 587                 hide_dotfiles = git_config_bool(var, value);
 588                 return 0;
 589         }
 590
 591         /* Add other config variables here and to Documentation/config.txt. */
 592         return 0;
 593 }
 594
 595 static int git_default_user_config(const char *var, const char *value)
 596 {
 597         if (!strcmp(var, "user.name")) {
 598                 if (!value)
 599                         return config_error_nonbool(var);
 600                 strlcpy(git_default_name, value, sizeof(git_default_name));
 601                 user_ident_explicitly_given |= IDENT_NAME_GIVEN;
 602                 return 0;
 603         }
 604
 605         if (!strcmp(var, "user.email")) {
 606                 if (!value)
 607                         return config_error_nonbool(var);
 608                 strlcpy(git_default_email, value, sizeof(git_default_email));
 609                 user_ident_explicitly_given |= IDENT_MAIL_GIVEN;
 610                 return 0;
 611         }
 612
 613         /* Add other config variables here and to Documentation/config.txt. */
 614         return 0;
 615 }
 616
 617 static int git_default_i18n_config(const char *var, const char *value)
 618 {
 619         if (!strcmp(var, "i18n.commitencoding"))
 620                 return git_config_string(&git_commit_encoding, var, value);
 621
 622         if (!strcmp(var, "i18n.logoutputencoding"))
 623                 return git_config_string(&git_log_output_encoding, var, value);
 624
 625         /* Add other config variables here and to Documentation/config.txt. */
 626         return 0;
 627 }
 628
 629 static int git_default_branch_config(const char *var, const char *value)
 630 {
 631         if (!strcmp(var, "branch.autosetupmerge")) {
 632                 if (value && !strcasecmp(value, "always")) {
 633                         git_branch_track = BRANCH_TRACK_ALWAYS;
 634                         return 0;
 635                 }
 636                 git_branch_track = git_config_bool(var, value);
 637                 return 0;
 638         }
 639         if (!strcmp(var, "branch.autosetuprebase")) {
 640                 if (!value)
 641                         return config_error_nonbool(var);
 642                 else if (!strcmp(value, "never"))
 643                         autorebase = AUTOREBASE_NEVER;
 644                 else if (!strcmp(value, "local"))
 645                         autorebase = AUTOREBASE_LOCAL;
 646                 else if (!strcmp(value, "remote"))
 647                         autorebase = AUTOREBASE_REMOTE;
 648                 else if (!strcmp(value, "always"))
 649                         autorebase = AUTOREBASE_ALWAYS;
 650                 else
 651                         return error("Malformed value for %s", var);
 652                 return 0;
 653         }
 654
 655         /* Add other config variables here and to Documentation/config.txt. */
 656         return 0;
 657 }
 658
 659 static int git_default_push_config(const char *var, const char *value)
 660 {
 661         if (!strcmp(var, "push.default")) {
 662                 if (!value)
 663                         return config_error_nonbool(var);
 664                 else if (!strcmp(value, "nothing"))
 665                         push_default = PUSH_DEFAULT_NOTHING;
 666                 else if (!strcmp(value, "matching"))
 667                         push_default = PUSH_DEFAULT_MATCHING;
 668                 else if (!strcmp(value, "tracking"))
 669                         push_default = PUSH_DEFAULT_TRACKING;
 670                 else if (!strcmp(value, "current"))
 671                         push_default = PUSH_DEFAULT_CURRENT;
 672                 else {
 673                         error("Malformed value for %s: %s", var, value);
 674                         return error("Must be one of nothing, matching, "
 675                                      "tracking or current.");
 676                 }
 677                 return 0;
 678         }
 679
 680         /* Add other config variables here and to Documentation/config.txt. */
 681         return 0;
 682 }
 683
 684 static int git_default_mailmap_config(const char *var, const char *value)
 685 {
 686         if (!strcmp(var, "mailmap.file"))
 687                 return git_config_string(&git_mailmap_file, var, value);
 688
 689         /* Add other config variables here and to Documentation/config.txt. */
 690         return 0;
 691 }
 692
 693 int git_default_config(const char *var, const char *value, void *dummy)
 694 {
 695         if (!prefixcmp(var, "core."))
 696                 return git_default_core_config(var, value);
 697
 698         if (!prefixcmp(var, "user."))
 699                 return git_default_user_config(var, value);
 700
 701         if (!prefixcmp(var, "i18n."))
 702                 return git_default_i18n_config(var, value);
 703
 704         if (!prefixcmp(var, "branch."))
 705                 return git_default_branch_config(var, value);
 706
 707         if (!prefixcmp(var, "push."))
 708                 return git_default_push_config(var, value);
 709
 710         if (!prefixcmp(var, "mailmap."))
 711                 return git_default_mailmap_config(var, value);
 712
 713         if (!prefixcmp(var, "advice."))
 714                 return git_default_advice_config(var, value);
 715
 716         if (!strcmp(var, "pager.color") || !strcmp(var, "color.pager")) {
 717                 pager_use_color = git_config_bool(var,value);
 718                 return 0;
 719         }
 720
 721         /* Add other config variables here and to Documentation/config.txt. */
 722         return 0;
 723 }
 724
 725 int git_config_from_file(config_fn_t fn, const char *filename, void *data)
 726 {
 727         int ret;
 728         FILE *f = fopen(filename, "r");
 729
 730         ret = -1;
 731         if (f) {
 732                 config_file = f;
 733                 config_file_name = filename;
 734                 config_linenr = 1;
 735                 config_file_eof = 0;
 736                 ret = git_parse_file(fn, data);
 737                 fclose(f);
 738                 config_file_name = NULL;
 739         }
 740         return ret;
 741 }
 742
 743 const char *git_etc_gitconfig(void)
 744 {
 745         static const char *system_wide;
 746         if (!system_wide)
 747                 system_wide = system_path(ETC_GITCONFIG);
 748         return system_wide;
 749 }
 750
 751 int git_env_bool(const char *k, int def)
 752 {
 753         const char *v = getenv(k);
 754         return v ? git_config_bool(k, v) : def;
 755 }
 756
 757 int git_config_system(void)
 758 {
 759         return !git_env_bool("GIT_CONFIG_NOSYSTEM", 0);
 760 }
 761
 762 int git_config_global(void)
 763 {
 764         return !git_env_bool("GIT_CONFIG_NOGLOBAL", 0);
 765 }
 766
 767 int git_config_from_parameters(config_fn_t fn, void *data)
 768 {
 769         const struct config_item *ct;
 770         for (ct = config_parameters; ct; ct = ct->next)
 771                 if (fn(ct->name, ct->value, data) < 0)
 772                         return -1;
 773         return 0;
 774 }
 775
 776 int git_config(config_fn_t fn, void *data)
 777 {
 778         int ret = 0, found = 0;
 779         char *repo_config = NULL;
 780         const char *home = NULL;
 781
 782         /* Setting $GIT_CONFIG makes git read _only_ the given config file. */
 783         if (config_exclusive_filename)
 784                 return git_config_from_file(fn, config_exclusive_filename, data);
 785         if (git_config_system() && !access(git_etc_gitconfig(), R_OK)) {
 786                 ret += git_config_from_file(fn, git_etc_gitconfig(),
 787                                             data);
 788                 found += 1;
 789         }
 790
 791         home = get_home_directory();
 792         if (git_config_global() && home) {
 793                 char *user_config = xstrdup(mkpath("%s/.gitconfig", home));
 794                 if (!access(user_config, R_OK)) {
 795                         ret += git_config_from_file(fn, user_config, data);
 796                         found += 1;
 797                 }
 798                 free(user_config);
 799         }
 800
 801         repo_config = git_pathdup("config");
 802         if (!access(repo_config, R_OK)) {
 803                 ret += git_config_from_file(fn, repo_config, data);
 804                 found += 1;
 805         }
 806         free(repo_config);
 807
 808         if (config_parameters) {
 809                 ret += git_config_from_parameters(fn, data);
 810                 found += 1;
 811         }
 812
 813         if (found == 0)
 814                 return -1;
 815         return ret;
 816 }
 817
 818 /*
 819  * Find all the stuff for git_config_set() below.
 820  */
 821
 822 #define MAX_MATCHES 512
 823
 824 static struct {
 825         int baselen;
 826         char *key;
 827         int do_not_match;
 828         regex_t *value_regex;
 829         int multi_replace;
 830         size_t offset[MAX_MATCHES];
 831         enum { START, SECTION_SEEN, SECTION_END_SEEN, KEY_SEEN } state;
 832         int seen;
 833 } store;
 834
 835 static int matches(const char *key, const char *value)
 836 {
 837         return !strcmp(key, store.key) &&
 838                 (store.value_regex == NULL ||
 839                  (store.do_not_match ^
 840                   !regexec(store.value_regex, value, 0, NULL, 0)));
 841 }
 842
 843 static int store_aux(const char *key, const char *value, void *cb)
 844 {
 845         const char *ep;
 846         size_t section_len;
 847
 848         switch (store.state) {
 849         case KEY_SEEN:
 850                 if (matches(key, value)) {
 851                         if (store.seen == 1 && store.multi_replace == 0) {
 852                                 warning("%s has multiple values", key);
 853                         } else if (store.seen >= MAX_MATCHES) {
 854                                 error("too many matches for %s", key);
 855                                 return 1;
 856                         }
 857
 858                         store.offset[store.seen] = ftell(config_file);
 859                         store.seen++;
 860                 }
 861                 break;
 862         case SECTION_SEEN:
 863                 /*
 864                  * What we are looking for is in store.key (both
 865                  * section and var), and its section part is baselen
 866                  * long.  We found key (again, both section and var).
 867                  * We would want to know if this key is in the same
 868                  * section as what we are looking for.  We already
 869                  * know we are in the same section as what should
 870                  * hold store.key.
 871                  */
 872                 ep = strrchr(key, '.');
 873                 section_len = ep - key;
 874
 875                 if ((section_len != store.baselen) ||
 876                     memcmp(key, store.key, section_len+1)) {
 877                         store.state = SECTION_END_SEEN;
 878                         break;
 879                 }
 880
 881                 /*
 882                  * Do not increment matches: this is no match, but we
 883                  * just made sure we are in the desired section.
 884                  */
 885                 store.offset[store.seen] = ftell(config_file);
 886                 /* fallthru */
 887         case SECTION_END_SEEN:
 888         case START:
 889                 if (matches(key, value)) {
 890                         store.offset[store.seen] = ftell(config_file);
 891                         store.state = KEY_SEEN;
 892                         store.seen++;
 893                 } else {
 894                         if (strrchr(key, '.') - key == store.baselen &&
 895                               !strncmp(key, store.key, store.baselen)) {
 896                                         store.state = SECTION_SEEN;
 897                                         store.offset[store.seen] = ftell(config_file);
 898                         }
 899                 }
 900         }
 901         return 0;
 902 }
 903
 904 static int write_error(const char *filename)
 905 {
 906         error("failed to write new configuration file %s", filename);
 907
 908         /* Same error code as "failed to rename". */
 909         return 4;
 910 }
 911
 912 static int store_write_section(int fd, const char *key)
 913 {
 914         const char *dot;
 915         int i, success;
 916         struct strbuf sb = STRBUF_INIT;
 917
 918         dot = memchr(key, '.', store.baselen);
 919         if (dot) {
 920                 strbuf_addf(&sb, "[%.*s \"", (int)(dot - key), key);
 921                 for (i = dot - key + 1; i < store.baselen; i++) {
 922                         if (key[i] == '"' || key[i] == '\\')
 923                                 strbuf_addch(&sb, '\\');
 924                         strbuf_addch(&sb, key[i]);
 925                 }
 926                 strbuf_addstr(&sb, "\"]\n");
 927         } else {
 928                 strbuf_addf(&sb, "[%.*s]\n", store.baselen, key);
 929         }
 930
 931         success = write_in_full(fd, sb.buf, sb.len) == sb.len;
 932         strbuf_release(&sb);
 933
 934         return success;
 935 }
 936
 937 static int store_write_pair(int fd, const char *key, const char *value)
 938 {
 939         int i, success;
 940         int length = strlen(key + store.baselen + 1);
 941         const char *quote = "";
 942         struct strbuf sb = STRBUF_INIT;
 943
 944         /*
 945          * Check to see if the value needs to be surrounded with a dq pair.
 946          * Note that problematic characters are always backslash-quoted; this
 947          * check is about not losing leading or trailing SP and strings that
 948          * follow beginning-of-comment characters (i.e. ';' and '#') by the
 949          * configuration parser.
 950          */
 951         if (value[0] == ' ')
 952                 quote = "\"";
 953         for (i = 0; value[i]; i++)
 954                 if (value[i] == ';' || value[i] == '#')
 955                         quote = "\"";
 956         if (i && value[i - 1] == ' ')
 957                 quote = "\"";
 958
 959         strbuf_addf(&sb, "\t%.*s = %s",
 960                     length, key + store.baselen + 1, quote);
 961
 962         for (i = 0; value[i]; i++)
 963                 switch (value[i]) {
 964                 case '\n':
 965                         strbuf_addstr(&sb, "\\n");
 966                         break;
 967                 case '\t':
 968                         strbuf_addstr(&sb, "\\t");
 969                         break;
 970                 case '"':
 971                 case '\\':
 972                         strbuf_addch(&sb, '\\');
 973                 default:
 974                         strbuf_addch(&sb, value[i]);
 975                         break;
 976                 }
 977         strbuf_addf(&sb, "%s\n", quote);
 978
 979         success = write_in_full(fd, sb.buf, sb.len) == sb.len;
 980         strbuf_release(&sb);
 981
 982         return success;
 983 }
 984
 985 static ssize_t find_beginning_of_line(const char *contents, size_t size,
 986         size_t offset_, int *found_bracket)
 987 {
 988         size_t equal_offset = size, bracket_offset = size;
 989         ssize_t offset;
 990
 991 contline:
 992         for (offset = offset_-2; offset > 0
 993                         && contents[offset] != '\n'; offset--)
 994                 switch (contents[offset]) {
 995                         case '=': equal_offset = offset; break;
 996                         case ']': bracket_offset = offset; break;
 997                 }
 998         if (offset > 0 && contents[offset-1] == '\\') {
 999                 offset_ = offset;
1000                 goto contline;
1001         }
1002         if (bracket_offset < equal_offset) {
1003                 *found_bracket = 1;
1004                 offset = bracket_offset+1;
1005         } else
1006                 offset++;
1007
1008         return offset;
1009 }
1010
1011 int git_config_set(const char *key, const char *value)
1012 {
1013         return git_config_set_multivar(key, value, NULL, 0);
1014 }
1015
1016 /*
1017  * If value==NULL, unset in (remove from) config,
1018  * if value_regex!=NULL, disregard key/value pairs where value does not match.
1019  * if multi_replace==0, nothing, or only one matching key/value is replaced,
1020  *     else all matching key/values (regardless how many) are removed,
1021  *     before the new pair is written.
1022  *
1023  * Returns 0 on success.
1024  *
1025  * This function does this:
1026  *
1027  * - it locks the config file by creating ".git/config.lock"
1028  *
1029  * - it then parses the config using store_aux() as validator to find
1030  *   the position on the key/value pair to replace. If it is to be unset,
1031  *   it must be found exactly once.
1032  *
1033  * - the config file is mmap()ed and the part before the match (if any) is
1034  *   written to the lock file, then the changed part and the rest.
1035  *
1036  * - the config file is removed and the lock file rename()d to it.
1037  *
1038  */
1039 int git_config_set_multivar(const char *key, const char *value,
1040         const char *value_regex, int multi_replace)
1041 {
1042         int i, dot;
1043         int fd = -1, in_fd;
1044         int ret;
1045         char *config_filename;
1046         struct lock_file *lock = NULL;
1047         const char *last_dot = strrchr(key, '.');
1048
1049         if (config_exclusive_filename)
1050                 config_filename = xstrdup(config_exclusive_filename);
1051         else
1052                 config_filename = git_pathdup("config");
1053
1054         /*
1055          * Since "key" actually contains the section name and the real
1056          * key name separated by a dot, we have to know where the dot is.
1057          */
1058
1059         if (last_dot == NULL) {
1060                 error("key does not contain a section: %s", key);
1061                 ret = 2;
1062                 goto out_free;
1063         }
1064         store.baselen = last_dot - key;
1065
1066         store.multi_replace = multi_replace;
1067
1068         /*
1069          * Validate the key and while at it, lower case it for matching.
1070          */
1071         store.key = xmalloc(strlen(key) + 1);
1072         dot = 0;
1073         for (i = 0; key[i]; i++) {
1074                 unsigned char c = key[i];
1075                 if (c == '.')
1076                         dot = 1;
1077                 /* Leave the extended basename untouched.. */
1078                 if (!dot || i > store.baselen) {
1079                         if (!iskeychar(c) || (i == store.baselen+1 && !isalpha(c))) {
1080                                 error("invalid key: %s", key);
1081                                 free(store.key);
1082                                 ret = 1;
1083                                 goto out_free;
1084                         }
1085                         c = tolower(c);
1086                 } else if (c == '\n') {
1087                         error("invalid key (newline): %s", key);
1088                         free(store.key);
1089                         ret = 1;
1090                         goto out_free;
1091                 }
1092                 store.key[i] = c;
1093         }
1094         store.key[i] = 0;
1095
1096         /*
1097          * The lock serves a purpose in addition to locking: the new
1098          * contents of .git/config will be written into it.
1099          */
1100         lock = xcalloc(sizeof(struct lock_file), 1);
1101         fd = hold_lock_file_for_update(lock, config_filename, 0);
1102         if (fd < 0) {
1103                 error("could not lock config file %s: %s", config_filename, strerror(errno));
1104                 free(store.key);
1105                 ret = -1;
1106                 goto out_free;
1107         }
1108
1109         /*
1110          * If .git/config does not exist yet, write a minimal version.
1111          */
1112         in_fd = open(config_filename, O_RDONLY);
1113         if ( in_fd < 0 ) {
1114                 free(store.key);
1115
1116                 if ( ENOENT != errno ) {
1117                         error("opening %s: %s", config_filename,
1118                               strerror(errno));
1119                         ret = 3; /* same as "invalid config file" */
1120                         goto out_free;
1121                 }
1122                 /* if nothing to unset, error out */
1123                 if (value == NULL) {
1124                         ret = 5;
1125                         goto out_free;
1126                 }
1127
1128                 store.key = (char *)key;
1129                 if (!store_write_section(fd, key) ||
1130                     !store_write_pair(fd, key, value))
1131                         goto write_err_out;
1132         } else {
1133                 struct stat st;
1134                 char *contents;
1135                 size_t contents_sz, copy_begin, copy_end;
1136                 int i, new_line = 0;
1137
1138                 if (value_regex == NULL)
1139                         store.value_regex = NULL;
1140                 else {
1141                         if (value_regex[0] == '!') {
1142                                 store.do_not_match = 1;
1143                                 value_regex++;
1144                         } else
1145                                 store.do_not_match = 0;
1146
1147                         store.value_regex = (regex_t*)xmalloc(sizeof(regex_t));
1148                         if (regcomp(store.value_regex, value_regex,
1149                                         REG_EXTENDED)) {
1150                                 error("invalid pattern: %s", value_regex);
1151                                 free(store.value_regex);
1152                                 ret = 6;
1153                                 goto out_free;
1154                         }
1155                 }
1156
1157                 store.offset[0] = 0;
1158                 store.state = START;
1159                 store.seen = 0;
1160
1161                 /*
1162                  * After this, store.offset will contain the *end* offset
1163                  * of the last match, or remain at 0 if no match was found.
1164                  * As a side effect, we make sure to transform only a valid
1165                  * existing config file.
1166                  */
1167                 if (git_config_from_file(store_aux, config_filename, NULL)) {
1168                         error("invalid config file %s", config_filename);
1169                         free(store.key);
1170                         if (store.value_regex != NULL) {
1171                                 regfree(store.value_regex);
1172                                 free(store.value_regex);
1173                         }
1174                         ret = 3;
1175                         goto out_free;
1176                 }
1177
1178                 free(store.key);
1179                 if (store.value_regex != NULL) {
1180                         regfree(store.value_regex);
1181                         free(store.value_regex);
1182                 }
1183
1184                 /* if nothing to unset, or too many matches, error out */
1185                 if ((store.seen == 0 && value == NULL) ||
1186                                 (store.seen > 1 && multi_replace == 0)) {
1187                         ret = 5;
1188                         goto out_free;
1189                 }
1190
1191                 fstat(in_fd, &st);
1192                 contents_sz = xsize_t(st.st_size);
1193                 contents = xmmap(NULL, contents_sz, PROT_READ,
1194                         MAP_PRIVATE, in_fd, 0);
1195                 close(in_fd);
1196
1197                 if (store.seen == 0)
1198                         store.seen = 1;
1199
1200                 for (i = 0, copy_begin = 0; i < store.seen; i++) {
1201                         if (store.offset[i] == 0) {
1202                                 store.offset[i] = copy_end = contents_sz;
1203                         } else if (store.state != KEY_SEEN) {
1204                                 copy_end = store.offset[i];
1205                         } else
1206                                 copy_end = find_beginning_of_line(
1207                                         contents, contents_sz,
1208                                         store.offset[i]-2, &new_line);
1209
1210                         if (copy_end > 0 && contents[copy_end-1] != '\n')
1211                                 new_line = 1;
1212
1213                         /* write the first part of the config */
1214                         if (copy_end > copy_begin) {
1215                                 if (write_in_full(fd, contents + copy_begin,
1216                                                   copy_end - copy_begin) <
1217                                     copy_end - copy_begin)
1218                                         goto write_err_out;
1219                                 if (new_line &&
1220                                     write_str_in_full(fd, "\n") != 1)
1221                                         goto write_err_out;
1222                         }
1223                         copy_begin = store.offset[i];
1224                 }
1225
1226                 /* write the pair (value == NULL means unset) */
1227                 if (value != NULL) {
1228                         if (store.state == START) {
1229                                 if (!store_write_section(fd, key))
1230                                         goto write_err_out;
1231                         }
1232                         if (!store_write_pair(fd, key, value))
1233                                 goto write_err_out;
1234                 }
1235
1236                 /* write the rest of the config */
1237                 if (copy_begin < contents_sz)
1238                         if (write_in_full(fd, contents + copy_begin,
1239                                           contents_sz - copy_begin) <
1240                             contents_sz - copy_begin)
1241                                 goto write_err_out;
1242
1243                 munmap(contents, contents_sz);
1244         }
1245
1246         if (commit_lock_file(lock) < 0) {
1247                 error("could not commit config file %s", config_filename);
1248                 ret = 4;
1249                 goto out_free;
1250         }
1251
1252         /*
1253          * lock is committed, so don't try to roll it back below.
1254          * NOTE: Since lockfile.c keeps a linked list of all created
1255          * lock_file structures, it isn't safe to free(lock).  It's
1256          * better to just leave it hanging around.
1257          */
1258         lock = NULL;
1259         ret = 0;
1260
1261 out_free:
1262         if (lock)
1263                 rollback_lock_file(lock);
1264         free(config_filename);
1265         return ret;
1266
1267 write_err_out:
1268         ret = write_error(lock->filename);
1269         goto out_free;
1270
1271 }
1272
1273 static int section_name_match (const char *buf, const char *name)
1274 {
1275         int i = 0, j = 0, dot = 0;
1276         if (buf[i] != '[')
1277                 return 0;
1278         for (i = 1; buf[i] && buf[i] != ']'; i++) {
1279                 if (!dot && isspace(buf[i])) {
1280                         dot = 1;
1281                         if (name[j++] != '.')
1282                                 break;
1283                         for (i++; isspace(buf[i]); i++)
1284                                 ; /* do nothing */
1285                         if (buf[i] != '"')
1286                                 break;
1287                         continue;
1288                 }
1289                 if (buf[i] == '\\' && dot)
1290                         i++;
1291                 else if (buf[i] == '"' && dot) {
1292                         for (i++; isspace(buf[i]); i++)
1293                                 ; /* do_nothing */
1294                         break;
1295                 }
1296                 if (buf[i] != name[j++])
1297                         break;
1298         }
1299         if (buf[i] == ']' && name[j] == 0) {
1300                 /*
1301                  * We match, now just find the right length offset by
1302                  * gobbling up any whitespace after it, as well
1303                  */
1304                 i++;
1305                 for (; buf[i] && isspace(buf[i]); i++)
1306                         ; /* do nothing */
1307                 return i;
1308         }
1309         return 0;
1310 }
1311
1312 /* if new_name == NULL, the section is removed instead */
1313 int git_config_rename_section(const char *old_name, const char *new_name)
1314 {
1315         int ret = 0, remove = 0;
1316         char *config_filename;
1317         struct lock_file *lock = xcalloc(sizeof(struct lock_file), 1);
1318         int out_fd;
1319         char buf[1024];
1320
1321         if (config_exclusive_filename)
1322                 config_filename = xstrdup(config_exclusive_filename);
1323         else
1324                 config_filename = git_pathdup("config");
1325         out_fd = hold_lock_file_for_update(lock, config_filename, 0);
1326         if (out_fd < 0) {
1327                 ret = error("could not lock config file %s", config_filename);
1328                 goto out;
1329         }
1330
1331         if (!(config_file = fopen(config_filename, "rb"))) {
1332                 /* no config file means nothing to rename, no error */
1333                 goto unlock_and_out;
1334         }
1335
1336         while (fgets(buf, sizeof(buf), config_file)) {
1337                 int i;
1338                 int length;
1339                 char *output = buf;
1340                 for (i = 0; buf[i] && isspace(buf[i]); i++)
1341                         ; /* do nothing */
1342                 if (buf[i] == '[') {
1343                         /* it's a section */
1344                         int offset = section_name_match(&buf[i], old_name);
1345                         if (offset > 0) {
1346                                 ret++;
1347                                 if (new_name == NULL) {
1348                                         remove = 1;
1349                                         continue;
1350                                 }
1351                                 store.baselen = strlen(new_name);
1352                                 if (!store_write_section(out_fd, new_name)) {
1353                                         ret = write_error(lock->filename);
1354                                         goto out;
1355                                 }
1356                                 /*
1357                                  * We wrote out the new section, with
1358                                  * a newline, now skip the old
1359                                  * section's length
1360                                  */
1361                                 output += offset + i;
1362                                 if (strlen(output) > 0) {
1363                                         /*
1364                                          * More content means there's
1365                                          * a declaration to put on the
1366                                          * next line; indent with a
1367                                          * tab
1368                                          */
1369                                         output -= 1;
1370                                         output[0] = '\t';
1371                                 }
1372                         }
1373                         remove = 0;
1374                 }
1375                 if (remove)
1376                         continue;
1377                 length = strlen(output);
1378                 if (write_in_full(out_fd, output, length) != length) {
1379                         ret = write_error(lock->filename);
1380                         goto out;
1381                 }
1382         }
1383         fclose(config_file);
1384  unlock_and_out:
1385         if (commit_lock_file(lock) < 0)
1386                 ret = error("could not commit config file %s", config_filename);
1387  out:
1388         free(config_filename);
1389         return ret;
1390 }
1391
1392 /*
1393  * Call this to report error for your variable that should not
1394  * get a boolean value (i.e. "[my] var" means "true").
1395  */
1396 int config_error_nonbool(const char *var)
1397 {
1398         return error("Missing value for '%s'", var);
1399 }