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