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