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 int git_config_pathname(const char **dest, const char *var, const char *value)
 355 {
 356         if (!value)
 357                 return config_error_nonbool(var);
 358         *dest = expand_user_path(value);
 359         if (!*dest)
 360                 die("Failed to expand user dir in: '%s'", value);
 361         return 0;
 362 }
 363
 364 static int git_default_core_config(const char *var, const char *value)
 365 {
 366         /* This needs a better name */
 367         if (!strcmp(var, "core.filemode")) {
 368                 trust_executable_bit = git_config_bool(var, value);
 369                 return 0;
 370         }
 371         if (!strcmp(var, "core.trustctime")) {
 372                 trust_ctime = git_config_bool(var, value);
 373                 return 0;
 374         }
 375
 376         if (!strcmp(var, "core.quotepath")) {
 377                 quote_path_fully = git_config_bool(var, value);
 378                 return 0;
 379         }
 380
 381         if (!strcmp(var, "core.symlinks")) {
 382                 has_symlinks = git_config_bool(var, value);
 383                 return 0;
 384         }
 385
 386         if (!strcmp(var, "core.ignorecase")) {
 387                 ignore_case = git_config_bool(var, value);
 388                 return 0;
 389         }
 390
 391         if (!strcmp(var, "core.bare")) {
 392                 is_bare_repository_cfg = git_config_bool(var, value);
 393                 return 0;
 394         }
 395
 396         if (!strcmp(var, "core.ignorestat")) {
 397                 assume_unchanged = git_config_bool(var, value);
 398                 return 0;
 399         }
 400
 401         if (!strcmp(var, "core.prefersymlinkrefs")) {
 402                 prefer_symlink_refs = git_config_bool(var, value);
 403                 return 0;
 404         }
 405
 406         if (!strcmp(var, "core.logallrefupdates")) {
 407                 log_all_ref_updates = git_config_bool(var, value);
 408                 return 0;
 409         }
 410
 411         if (!strcmp(var, "core.warnambiguousrefs")) {
 412                 warn_ambiguous_refs = git_config_bool(var, value);
 413                 return 0;
 414         }
 415
 416         if (!strcmp(var, "core.loosecompression")) {
 417                 int level = git_config_int(var, value);
 418                 if (level == -1)
 419                         level = Z_DEFAULT_COMPRESSION;
 420                 else if (level < 0 || level > Z_BEST_COMPRESSION)
 421                         die("bad zlib compression level %d", level);
 422                 zlib_compression_level = level;
 423                 zlib_compression_seen = 1;
 424                 return 0;
 425         }
 426
 427         if (!strcmp(var, "core.compression")) {
 428                 int level = git_config_int(var, value);
 429                 if (level == -1)
 430                         level = Z_DEFAULT_COMPRESSION;
 431                 else if (level < 0 || level > Z_BEST_COMPRESSION)
 432                         die("bad zlib compression level %d", level);
 433                 core_compression_level = level;
 434                 core_compression_seen = 1;
 435                 if (!zlib_compression_seen)
 436                         zlib_compression_level = level;
 437                 return 0;
 438         }
 439
 440         if (!strcmp(var, "core.packedgitwindowsize")) {
 441                 int pgsz_x2 = getpagesize() * 2;
 442                 packed_git_window_size = git_config_int(var, value);
 443
 444                 /* This value must be multiple of (pagesize * 2) */
 445                 packed_git_window_size /= pgsz_x2;
 446                 if (packed_git_window_size < 1)
 447                         packed_git_window_size = 1;
 448                 packed_git_window_size *= pgsz_x2;
 449                 return 0;
 450         }
 451
 452         if (!strcmp(var, "core.packedgitlimit")) {
 453                 packed_git_limit = git_config_int(var, value);
 454                 return 0;
 455         }
 456
 457         if (!strcmp(var, "core.deltabasecachelimit")) {
 458                 delta_base_cache_limit = git_config_int(var, value);
 459                 return 0;
 460         }
 461
 462         if (!strcmp(var, "core.autocrlf")) {
 463                 if (value && !strcasecmp(value, "input")) {
 464                         auto_crlf = -1;
 465                         return 0;
 466                 }
 467                 auto_crlf = git_config_bool(var, value);
 468                 return 0;
 469         }
 470
 471         if (!strcmp(var, "core.safecrlf")) {
 472                 if (value && !strcasecmp(value, "warn")) {
 473                         safe_crlf = SAFE_CRLF_WARN;
 474                         return 0;
 475                 }
 476                 safe_crlf = git_config_bool(var, value);
 477                 return 0;
 478         }
 479
 480         if (!strcmp(var, "core.notesref")) {
 481                 notes_ref_name = xstrdup(value);
 482                 return 0;
 483         }
 484
 485         if (!strcmp(var, "core.pager"))
 486                 return git_config_string(&pager_program, var, value);
 487
 488         if (!strcmp(var, "core.editor"))
 489                 return git_config_string(&editor_program, var, value);
 490
 491         if (!strcmp(var, "core.excludesfile"))
 492                 return git_config_pathname(&excludes_file, var, value);
 493
 494         if (!strcmp(var, "core.whitespace")) {
 495                 if (!value)
 496                         return config_error_nonbool(var);
 497                 whitespace_rule_cfg = parse_whitespace_rule(value);
 498                 return 0;
 499         }
 500
 501         if (!strcmp(var, "core.fsyncobjectfiles")) {
 502                 fsync_object_files = git_config_bool(var, value);
 503                 return 0;
 504         }
 505
 506         if (!strcmp(var, "core.preloadindex")) {
 507                 core_preload_index = git_config_bool(var, value);
 508                 return 0;
 509         }
 510
 511         if (!strcmp(var, "core.createobject")) {
 512                 if (!strcmp(value, "rename"))
 513                         object_creation_mode = OBJECT_CREATION_USES_RENAMES;
 514                 else if (!strcmp(value, "link"))
 515                         object_creation_mode = OBJECT_CREATION_USES_HARDLINKS;
 516                 else
 517                         die("Invalid mode for object creation: %s", value);
 518                 return 0;
 519         }
 520
 521         if (!strcmp(var, "core.sparsecheckout")) {
 522                 core_apply_sparse_checkout = git_config_bool(var, value);
 523                 return 0;
 524         }
 525
 526         /* Add other config variables here and to Documentation/config.txt. */
 527         return 0;
 528 }
 529
 530 static int git_default_user_config(const char *var, const char *value)
 531 {
 532         if (!strcmp(var, "user.name")) {
 533                 if (!value)
 534                         return config_error_nonbool(var);
 535                 strlcpy(git_default_name, value, sizeof(git_default_name));
 536                 user_ident_explicitly_given |= IDENT_NAME_GIVEN;
 537                 return 0;
 538         }
 539
 540         if (!strcmp(var, "user.email")) {
 541                 if (!value)
 542                         return config_error_nonbool(var);
 543                 strlcpy(git_default_email, value, sizeof(git_default_email));
 544                 user_ident_explicitly_given |= IDENT_MAIL_GIVEN;
 545                 return 0;
 546         }
 547
 548         /* Add other config variables here and to Documentation/config.txt. */
 549         return 0;
 550 }
 551
 552 static int git_default_i18n_config(const char *var, const char *value)
 553 {
 554         if (!strcmp(var, "i18n.commitencoding"))
 555                 return git_config_string(&git_commit_encoding, var, value);
 556
 557         if (!strcmp(var, "i18n.logoutputencoding"))
 558                 return git_config_string(&git_log_output_encoding, var, value);
 559
 560         /* Add other config variables here and to Documentation/config.txt. */
 561         return 0;
 562 }
 563
 564 static int git_default_branch_config(const char *var, const char *value)
 565 {
 566         if (!strcmp(var, "branch.autosetupmerge")) {
 567                 if (value && !strcasecmp(value, "always")) {
 568                         git_branch_track = BRANCH_TRACK_ALWAYS;
 569                         return 0;
 570                 }
 571                 git_branch_track = git_config_bool(var, value);
 572                 return 0;
 573         }
 574         if (!strcmp(var, "branch.autosetuprebase")) {
 575                 if (!value)
 576                         return config_error_nonbool(var);
 577                 else if (!strcmp(value, "never"))
 578                         autorebase = AUTOREBASE_NEVER;
 579                 else if (!strcmp(value, "local"))
 580                         autorebase = AUTOREBASE_LOCAL;
 581                 else if (!strcmp(value, "remote"))
 582                         autorebase = AUTOREBASE_REMOTE;
 583                 else if (!strcmp(value, "always"))
 584                         autorebase = AUTOREBASE_ALWAYS;
 585                 else
 586                         return error("Malformed value for %s", var);
 587                 return 0;
 588         }
 589
 590         /* Add other config variables here and to Documentation/config.txt. */
 591         return 0;
 592 }
 593
 594 static int git_default_push_config(const char *var, const char *value)
 595 {
 596         if (!strcmp(var, "push.default")) {
 597                 if (!value)
 598                         return config_error_nonbool(var);
 599                 else if (!strcmp(value, "nothing"))
 600                         push_default = PUSH_DEFAULT_NOTHING;
 601                 else if (!strcmp(value, "matching"))
 602                         push_default = PUSH_DEFAULT_MATCHING;
 603                 else if (!strcmp(value, "tracking"))
 604                         push_default = PUSH_DEFAULT_TRACKING;
 605                 else if (!strcmp(value, "current"))
 606                         push_default = PUSH_DEFAULT_CURRENT;
 607                 else {
 608                         error("Malformed value for %s: %s", var, value);
 609                         return error("Must be one of nothing, matching, "
 610                                      "tracking or current.");
 611                 }
 612                 return 0;
 613         }
 614
 615         /* Add other config variables here and to Documentation/config.txt. */
 616         return 0;
 617 }
 618
 619 static int git_default_mailmap_config(const char *var, const char *value)
 620 {
 621         if (!strcmp(var, "mailmap.file"))
 622                 return git_config_string(&git_mailmap_file, var, value);
 623
 624         /* Add other config variables here and to Documentation/config.txt. */
 625         return 0;
 626 }
 627
 628 int git_default_config(const char *var, const char *value, void *dummy)
 629 {
 630         if (!prefixcmp(var, "core."))
 631                 return git_default_core_config(var, value);
 632
 633         if (!prefixcmp(var, "user."))
 634                 return git_default_user_config(var, value);
 635
 636         if (!prefixcmp(var, "i18n."))
 637                 return git_default_i18n_config(var, value);
 638
 639         if (!prefixcmp(var, "branch."))
 640                 return git_default_branch_config(var, value);
 641
 642         if (!prefixcmp(var, "push."))
 643                 return git_default_push_config(var, value);
 644
 645         if (!prefixcmp(var, "mailmap."))
 646                 return git_default_mailmap_config(var, value);
 647
 648         if (!prefixcmp(var, "advice."))
 649                 return git_default_advice_config(var, value);
 650
 651         if (!strcmp(var, "pager.color") || !strcmp(var, "color.pager")) {
 652                 pager_use_color = git_config_bool(var,value);
 653                 return 0;
 654         }
 655
 656         /* Add other config variables here and to Documentation/config.txt. */
 657         return 0;
 658 }
 659
 660 int git_config_from_file(config_fn_t fn, const char *filename, void *data)
 661 {
 662         int ret;
 663         FILE *f = fopen(filename, "r");
 664
 665         ret = -1;
 666         if (f) {
 667                 config_file = f;
 668                 config_file_name = filename;
 669                 config_linenr = 1;
 670                 config_file_eof = 0;
 671                 ret = git_parse_file(fn, data);
 672                 fclose(f);
 673                 config_file_name = NULL;
 674         }
 675         return ret;
 676 }
 677
 678 const char *git_etc_gitconfig(void)
 679 {
 680         static const char *system_wide;
 681         if (!system_wide)
 682                 system_wide = system_path(ETC_GITCONFIG);
 683         return system_wide;
 684 }
 685
 686 static int git_env_bool(const char *k, int def)
 687 {
 688         const char *v = getenv(k);
 689         return v ? git_config_bool(k, v) : def;
 690 }
 691
 692 int git_config_system(void)
 693 {
 694         return !git_env_bool("GIT_CONFIG_NOSYSTEM", 0);
 695 }
 696
 697 int git_config_global(void)
 698 {
 699         return !git_env_bool("GIT_CONFIG_NOGLOBAL", 0);
 700 }
 701
 702 int git_config(config_fn_t fn, void *data)
 703 {
 704         int ret = 0, found = 0;
 705         char *repo_config = NULL;
 706         const char *home = NULL;
 707
 708         /* Setting $GIT_CONFIG makes git read _only_ the given config file. */
 709         if (config_exclusive_filename)
 710                 return git_config_from_file(fn, config_exclusive_filename, data);
 711         if (git_config_system() && !access(git_etc_gitconfig(), R_OK)) {
 712                 ret += git_config_from_file(fn, git_etc_gitconfig(),
 713                                             data);
 714                 found += 1;
 715         }
 716
 717         home = getenv("HOME");
 718         if (git_config_global() && home) {
 719                 char *user_config = xstrdup(mkpath("%s/.gitconfig", home));
 720                 if (!access(user_config, R_OK)) {
 721                         ret += git_config_from_file(fn, user_config, data);
 722                         found += 1;
 723                 }
 724                 free(user_config);
 725         }
 726
 727         repo_config = git_pathdup("config");
 728         if (!access(repo_config, R_OK)) {
 729                 ret += git_config_from_file(fn, repo_config, data);
 730                 found += 1;
 731         }
 732         free(repo_config);
 733         if (found == 0)
 734                 return -1;
 735         return ret;
 736 }
 737
 738 /*
 739  * Find all the stuff for git_config_set() below.
 740  */
 741
 742 #define MAX_MATCHES 512
 743
 744 static struct {
 745         int baselen;
 746         char *key;
 747         int do_not_match;
 748         regex_t *value_regex;
 749         int multi_replace;
 750         size_t offset[MAX_MATCHES];
 751         enum { START, SECTION_SEEN, SECTION_END_SEEN, KEY_SEEN } state;
 752         int seen;
 753 } store;
 754
 755 static int matches(const char *key, const char *value)
 756 {
 757         return !strcmp(key, store.key) &&
 758                 (store.value_regex == NULL ||
 759                  (store.do_not_match ^
 760                   !regexec(store.value_regex, value, 0, NULL, 0)));
 761 }
 762
 763 static int store_aux(const char *key, const char *value, void *cb)
 764 {
 765         const char *ep;
 766         size_t section_len;
 767
 768         switch (store.state) {
 769         case KEY_SEEN:
 770                 if (matches(key, value)) {
 771                         if (store.seen == 1 && store.multi_replace == 0) {
 772                                 warning("%s has multiple values", key);
 773                         } else if (store.seen >= MAX_MATCHES) {
 774                                 error("too many matches for %s", key);
 775                                 return 1;
 776                         }
 777
 778                         store.offset[store.seen] = ftell(config_file);
 779                         store.seen++;
 780                 }
 781                 break;
 782         case SECTION_SEEN:
 783                 /*
 784                  * What we are looking for is in store.key (both
 785                  * section and var), and its section part is baselen
 786                  * long.  We found key (again, both section and var).
 787                  * We would want to know if this key is in the same
 788                  * section as what we are looking for.  We already
 789                  * know we are in the same section as what should
 790                  * hold store.key.
 791                  */
 792                 ep = strrchr(key, '.');
 793                 section_len = ep - key;
 794
 795                 if ((section_len != store.baselen) ||
 796                     memcmp(key, store.key, section_len+1)) {
 797                         store.state = SECTION_END_SEEN;
 798                         break;
 799                 }
 800
 801                 /*
 802                  * Do not increment matches: this is no match, but we
 803                  * just made sure we are in the desired section.
 804                  */
 805                 store.offset[store.seen] = ftell(config_file);
 806                 /* fallthru */
 807         case SECTION_END_SEEN:
 808         case START:
 809                 if (matches(key, value)) {
 810                         store.offset[store.seen] = ftell(config_file);
 811                         store.state = KEY_SEEN;
 812                         store.seen++;
 813                 } else {
 814                         if (strrchr(key, '.') - key == store.baselen &&
 815                               !strncmp(key, store.key, store.baselen)) {
 816                                         store.state = SECTION_SEEN;
 817                                         store.offset[store.seen] = ftell(config_file);
 818                         }
 819                 }
 820         }
 821         return 0;
 822 }
 823
 824 static int write_error(const char *filename)
 825 {
 826         error("failed to write new configuration file %s", filename);
 827
 828         /* Same error code as "failed to rename". */
 829         return 4;
 830 }
 831
 832 static int store_write_section(int fd, const char *key)
 833 {
 834         const char *dot;
 835         int i, success;
 836         struct strbuf sb = STRBUF_INIT;
 837
 838         dot = memchr(key, '.', store.baselen);
 839         if (dot) {
 840                 strbuf_addf(&sb, "[%.*s \"", (int)(dot - key), key);
 841                 for (i = dot - key + 1; i < store.baselen; i++) {
 842                         if (key[i] == '"' || key[i] == '\\')
 843                                 strbuf_addch(&sb, '\\');
 844                         strbuf_addch(&sb, key[i]);
 845                 }
 846                 strbuf_addstr(&sb, "\"]\n");
 847         } else {
 848                 strbuf_addf(&sb, "[%.*s]\n", store.baselen, key);
 849         }
 850
 851         success = write_in_full(fd, sb.buf, sb.len) == sb.len;
 852         strbuf_release(&sb);
 853
 854         return success;
 855 }
 856
 857 static int store_write_pair(int fd, const char *key, const char *value)
 858 {
 859         int i, success;
 860         int length = strlen(key + store.baselen + 1);
 861         const char *quote = "";
 862         struct strbuf sb = STRBUF_INIT;
 863
 864         /*
 865          * Check to see if the value needs to be surrounded with a dq pair.
 866          * Note that problematic characters are always backslash-quoted; this
 867          * check is about not losing leading or trailing SP and strings that
 868          * follow beginning-of-comment characters (i.e. ';' and '#') by the
 869          * configuration parser.
 870          */
 871         if (value[0] == ' ')
 872                 quote = "\"";
 873         for (i = 0; value[i]; i++)
 874                 if (value[i] == ';' || value[i] == '#')
 875                         quote = "\"";
 876         if (i && value[i - 1] == ' ')
 877                 quote = "\"";
 878
 879         strbuf_addf(&sb, "\t%.*s = %s",
 880                     length, key + store.baselen + 1, quote);
 881
 882         for (i = 0; value[i]; i++)
 883                 switch (value[i]) {
 884                 case '\n':
 885                         strbuf_addstr(&sb, "\\n");
 886                         break;
 887                 case '\t':
 888                         strbuf_addstr(&sb, "\\t");
 889                         break;
 890                 case '"':
 891                 case '\\':
 892                         strbuf_addch(&sb, '\\');
 893                 default:
 894                         strbuf_addch(&sb, value[i]);
 895                         break;
 896                 }
 897         strbuf_addf(&sb, "%s\n", quote);
 898
 899         success = write_in_full(fd, sb.buf, sb.len) == sb.len;
 900         strbuf_release(&sb);
 901
 902         return success;
 903 }
 904
 905 static ssize_t find_beginning_of_line(const char *contents, size_t size,
 906         size_t offset_, int *found_bracket)
 907 {
 908         size_t equal_offset = size, bracket_offset = size;
 909         ssize_t offset;
 910
 911 contline:
 912         for (offset = offset_-2; offset > 0
 913                         && contents[offset] != '\n'; offset--)
 914                 switch (contents[offset]) {
 915                         case '=': equal_offset = offset; break;
 916                         case ']': bracket_offset = offset; break;
 917                 }
 918         if (offset > 0 && contents[offset-1] == '\\') {
 919                 offset_ = offset;
 920                 goto contline;
 921         }
 922         if (bracket_offset < equal_offset) {
 923                 *found_bracket = 1;
 924                 offset = bracket_offset+1;
 925         } else
 926                 offset++;
 927
 928         return offset;
 929 }
 930
 931 int git_config_set(const char *key, const char *value)
 932 {
 933         return git_config_set_multivar(key, value, NULL, 0);
 934 }
 935
 936 /*
 937  * If value==NULL, unset in (remove from) config,
 938  * if value_regex!=NULL, disregard key/value pairs where value does not match.
 939  * if multi_replace==0, nothing, or only one matching key/value is replaced,
 940  *     else all matching key/values (regardless how many) are removed,
 941  *     before the new pair is written.
 942  *
 943  * Returns 0 on success.
 944  *
 945  * This function does this:
 946  *
 947  * - it locks the config file by creating ".git/config.lock"
 948  *
 949  * - it then parses the config using store_aux() as validator to find
 950  *   the position on the key/value pair to replace. If it is to be unset,
 951  *   it must be found exactly once.
 952  *
 953  * - the config file is mmap()ed and the part before the match (if any) is
 954  *   written to the lock file, then the changed part and the rest.
 955  *
 956  * - the config file is removed and the lock file rename()d to it.
 957  *
 958  */
 959 int git_config_set_multivar(const char *key, const char *value,
 960         const char *value_regex, int multi_replace)
 961 {
 962         int i, dot;
 963         int fd = -1, in_fd;
 964         int ret;
 965         char *config_filename;
 966         struct lock_file *lock = NULL;
 967         const char *last_dot = strrchr(key, '.');
 968
 969         if (config_exclusive_filename)
 970                 config_filename = xstrdup(config_exclusive_filename);
 971         else
 972                 config_filename = git_pathdup("config");
 973
 974         /*
 975          * Since "key" actually contains the section name and the real
 976          * key name separated by a dot, we have to know where the dot is.
 977          */
 978
 979         if (last_dot == NULL) {
 980                 error("key does not contain a section: %s", key);
 981                 ret = 2;
 982                 goto out_free;
 983         }
 984         store.baselen = last_dot - key;
 985
 986         store.multi_replace = multi_replace;
 987
 988         /*
 989          * Validate the key and while at it, lower case it for matching.
 990          */
 991         store.key = xmalloc(strlen(key) + 1);
 992         dot = 0;
 993         for (i = 0; key[i]; i++) {
 994                 unsigned char c = key[i];
 995                 if (c == '.')
 996                         dot = 1;
 997                 /* Leave the extended basename untouched.. */
 998                 if (!dot || i > store.baselen) {
 999                         if (!iskeychar(c) || (i == store.baselen+1 && !isalpha(c))) {
1000                                 error("invalid key: %s", key);
1001                                 free(store.key);
1002                                 ret = 1;
1003                                 goto out_free;
1004                         }
1005                         c = tolower(c);
1006                 } else if (c == '\n') {
1007                         error("invalid key (newline): %s", key);
1008                         free(store.key);
1009                         ret = 1;
1010                         goto out_free;
1011                 }
1012                 store.key[i] = c;
1013         }
1014         store.key[i] = 0;
1015
1016         /*
1017          * The lock serves a purpose in addition to locking: the new
1018          * contents of .git/config will be written into it.
1019          */
1020         lock = xcalloc(sizeof(struct lock_file), 1);
1021         fd = hold_lock_file_for_update(lock, config_filename, 0);
1022         if (fd < 0) {
1023                 error("could not lock config file %s: %s", config_filename, strerror(errno));
1024                 free(store.key);
1025                 ret = -1;
1026                 goto out_free;
1027         }
1028
1029         /*
1030          * If .git/config does not exist yet, write a minimal version.
1031          */
1032         in_fd = open(config_filename, O_RDONLY);
1033         if ( in_fd < 0 ) {
1034                 free(store.key);
1035
1036                 if ( ENOENT != errno ) {
1037                         error("opening %s: %s", config_filename,
1038                               strerror(errno));
1039                         ret = 3; /* same as "invalid config file" */
1040                         goto out_free;
1041                 }
1042                 /* if nothing to unset, error out */
1043                 if (value == NULL) {
1044                         ret = 5;
1045                         goto out_free;
1046                 }
1047
1048                 store.key = (char *)key;
1049                 if (!store_write_section(fd, key) ||
1050                     !store_write_pair(fd, key, value))
1051                         goto write_err_out;
1052         } else {
1053                 struct stat st;
1054                 char *contents;
1055                 size_t contents_sz, copy_begin, copy_end;
1056                 int i, new_line = 0;
1057
1058                 if (value_regex == NULL)
1059                         store.value_regex = NULL;
1060                 else {
1061                         if (value_regex[0] == '!') {
1062                                 store.do_not_match = 1;
1063                                 value_regex++;
1064                         } else
1065                                 store.do_not_match = 0;
1066
1067                         store.value_regex = (regex_t*)xmalloc(sizeof(regex_t));
1068                         if (regcomp(store.value_regex, value_regex,
1069                                         REG_EXTENDED)) {
1070                                 error("invalid pattern: %s", value_regex);
1071                                 free(store.value_regex);
1072                                 ret = 6;
1073                                 goto out_free;
1074                         }
1075                 }
1076
1077                 store.offset[0] = 0;
1078                 store.state = START;
1079                 store.seen = 0;
1080
1081                 /*
1082                  * After this, store.offset will contain the *end* offset
1083                  * of the last match, or remain at 0 if no match was found.
1084                  * As a side effect, we make sure to transform only a valid
1085                  * existing config file.
1086                  */
1087                 if (git_config_from_file(store_aux, config_filename, NULL)) {
1088                         error("invalid config file %s", config_filename);
1089                         free(store.key);
1090                         if (store.value_regex != NULL) {
1091                                 regfree(store.value_regex);
1092                                 free(store.value_regex);
1093                         }
1094                         ret = 3;
1095                         goto out_free;
1096                 }
1097
1098                 free(store.key);
1099                 if (store.value_regex != NULL) {
1100                         regfree(store.value_regex);
1101                         free(store.value_regex);
1102                 }
1103
1104                 /* if nothing to unset, or too many matches, error out */
1105                 if ((store.seen == 0 && value == NULL) ||
1106                                 (store.seen > 1 && multi_replace == 0)) {
1107                         ret = 5;
1108                         goto out_free;
1109                 }
1110
1111                 fstat(in_fd, &st);
1112                 contents_sz = xsize_t(st.st_size);
1113                 contents = xmmap(NULL, contents_sz, PROT_READ,
1114                         MAP_PRIVATE, in_fd, 0);
1115                 close(in_fd);
1116
1117                 if (store.seen == 0)
1118                         store.seen = 1;
1119
1120                 for (i = 0, copy_begin = 0; i < store.seen; i++) {
1121                         if (store.offset[i] == 0) {
1122                                 store.offset[i] = copy_end = contents_sz;
1123                         } else if (store.state != KEY_SEEN) {
1124                                 copy_end = store.offset[i];
1125                         } else
1126                                 copy_end = find_beginning_of_line(
1127                                         contents, contents_sz,
1128                                         store.offset[i]-2, &new_line);
1129
1130                         if (copy_end > 0 && contents[copy_end-1] != '\n')
1131                                 new_line = 1;
1132
1133                         /* write the first part of the config */
1134                         if (copy_end > copy_begin) {
1135                                 if (write_in_full(fd, contents + copy_begin,
1136                                                   copy_end - copy_begin) <
1137                                     copy_end - copy_begin)
1138                                         goto write_err_out;
1139                                 if (new_line &&
1140                                     write_str_in_full(fd, "\n") != 1)
1141                                         goto write_err_out;
1142                         }
1143                         copy_begin = store.offset[i];
1144                 }
1145
1146                 /* write the pair (value == NULL means unset) */
1147                 if (value != NULL) {
1148                         if (store.state == START) {
1149                                 if (!store_write_section(fd, key))
1150                                         goto write_err_out;
1151                         }
1152                         if (!store_write_pair(fd, key, value))
1153                                 goto write_err_out;
1154                 }
1155
1156                 /* write the rest of the config */
1157                 if (copy_begin < contents_sz)
1158                         if (write_in_full(fd, contents + copy_begin,
1159                                           contents_sz - copy_begin) <
1160                             contents_sz - copy_begin)
1161                                 goto write_err_out;
1162
1163                 munmap(contents, contents_sz);
1164         }
1165
1166         if (commit_lock_file(lock) < 0) {
1167                 error("could not commit config file %s", config_filename);
1168                 ret = 4;
1169                 goto out_free;
1170         }
1171
1172         /*
1173          * lock is committed, so don't try to roll it back below.
1174          * NOTE: Since lockfile.c keeps a linked list of all created
1175          * lock_file structures, it isn't safe to free(lock).  It's
1176          * better to just leave it hanging around.
1177          */
1178         lock = NULL;
1179         ret = 0;
1180
1181 out_free:
1182         if (lock)
1183                 rollback_lock_file(lock);
1184         free(config_filename);
1185         return ret;
1186
1187 write_err_out:
1188         ret = write_error(lock->filename);
1189         goto out_free;
1190
1191 }
1192
1193 static int section_name_match (const char *buf, const char *name)
1194 {
1195         int i = 0, j = 0, dot = 0;
1196         if (buf[i] != '[')
1197                 return 0;
1198         for (i = 1; buf[i] && buf[i] != ']'; i++) {
1199                 if (!dot && isspace(buf[i])) {
1200                         dot = 1;
1201                         if (name[j++] != '.')
1202                                 break;
1203                         for (i++; isspace(buf[i]); i++)
1204                                 ; /* do nothing */
1205                         if (buf[i] != '"')
1206                                 break;
1207                         continue;
1208                 }
1209                 if (buf[i] == '\\' && dot)
1210                         i++;
1211                 else if (buf[i] == '"' && dot) {
1212                         for (i++; isspace(buf[i]); i++)
1213                                 ; /* do_nothing */
1214                         break;
1215                 }
1216                 if (buf[i] != name[j++])
1217                         break;
1218         }
1219         if (buf[i] == ']' && name[j] == 0) {
1220                 /*
1221                  * We match, now just find the right length offset by
1222                  * gobbling up any whitespace after it, as well
1223                  */
1224                 i++;
1225                 for (; buf[i] && isspace(buf[i]); i++)
1226                         ; /* do nothing */
1227                 return i;
1228         }
1229         return 0;
1230 }
1231
1232 /* if new_name == NULL, the section is removed instead */
1233 int git_config_rename_section(const char *old_name, const char *new_name)
1234 {
1235         int ret = 0, remove = 0;
1236         char *config_filename;
1237         struct lock_file *lock = xcalloc(sizeof(struct lock_file), 1);
1238         int out_fd;
1239         char buf[1024];
1240
1241         if (config_exclusive_filename)
1242                 config_filename = xstrdup(config_exclusive_filename);
1243         else
1244                 config_filename = git_pathdup("config");
1245         out_fd = hold_lock_file_for_update(lock, config_filename, 0);
1246         if (out_fd < 0) {
1247                 ret = error("could not lock config file %s", config_filename);
1248                 goto out;
1249         }
1250
1251         if (!(config_file = fopen(config_filename, "rb"))) {
1252                 /* no config file means nothing to rename, no error */
1253                 goto unlock_and_out;
1254         }
1255
1256         while (fgets(buf, sizeof(buf), config_file)) {
1257                 int i;
1258                 int length;
1259                 char *output = buf;
1260                 for (i = 0; buf[i] && isspace(buf[i]); i++)
1261                         ; /* do nothing */
1262                 if (buf[i] == '[') {
1263                         /* it's a section */
1264                         int offset = section_name_match(&buf[i], old_name);
1265                         if (offset > 0) {
1266                                 ret++;
1267                                 if (new_name == NULL) {
1268                                         remove = 1;
1269                                         continue;
1270                                 }
1271                                 store.baselen = strlen(new_name);
1272                                 if (!store_write_section(out_fd, new_name)) {
1273                                         ret = write_error(lock->filename);
1274                                         goto out;
1275                                 }
1276                                 /*
1277                                  * We wrote out the new section, with
1278                                  * a newline, now skip the old
1279                                  * section's length
1280                                  */
1281                                 output += offset + i;
1282                                 if (strlen(output) > 0) {
1283                                         /*
1284                                          * More content means there's
1285                                          * a declaration to put on the
1286                                          * next line; indent with a
1287                                          * tab
1288                                          */
1289                                         output -= 1;
1290                                         output[0] = '\t';
1291                                 }
1292                         }
1293                         remove = 0;
1294                 }
1295                 if (remove)
1296                         continue;
1297                 length = strlen(output);
1298                 if (write_in_full(out_fd, output, length) != length) {
1299                         ret = write_error(lock->filename);
1300                         goto out;
1301                 }
1302         }
1303         fclose(config_file);
1304  unlock_and_out:
1305         if (commit_lock_file(lock) < 0)
1306                 ret = error("could not commit config file %s", config_filename);
1307  out:
1308         free(config_filename);
1309         return ret;
1310 }
1311
1312 /*
1313  * Call this to report error for your variable that should not
1314  * get a boolean value (i.e. "[my] var" means "true").
1315  */
1316 int config_error_nonbool(const char *var)
1317 {
1318         return error("Missing value for '%s'", var);
1319 }