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                         space = 1;
  66                         continue;
  67                 }
  68                 if (!quote) {
  69                         if (c == ';' || c == '#') {
  70                                 comment = 1;
  71                                 continue;
  72                         }
  73                 }
  74                 if (space) {
  75                         if (len)
  76                                 value[len++] = ' ';
  77                         space = 0;
  78                 }
  79                 if (c == '\\') {
  80                         c = get_next_char();
  81                         switch (c) {
  82                         case '\n':
  83                                 continue;
  84                         case 't':
  85                                 c = '\t';
  86                                 break;
  87                         case 'b':
  88                                 c = '\b';
  89                                 break;
  90                         case 'n':
  91                                 c = '\n';
  92                                 break;
  93                         /* Some characters escape as themselves */
  94                         case '\\': case '"':
  95                                 break;
  96                         /* Reject unknown escape sequences */
  97                         default:
  98                                 return NULL;
  99                         }
 100                         value[len++] = c;
 101                         continue;
 102                 }
 103                 if (c == '"') {
 104                         quote = 1-quote;
 105                         continue;
 106                 }
 107                 value[len++] = c;
 108         }
 109 }
 110
 111 static inline int iskeychar(int c)
 112 {
 113         return isalnum(c) || c == '-';
 114 }
 115
 116 static int get_value(config_fn_t fn, void *data, char *name, unsigned int len)
 117 {
 118         int c;
 119         char *value;
 120
 121         /* Get the full name */
 122         for (;;) {
 123                 c = get_next_char();
 124                 if (config_file_eof)
 125                         break;
 126                 if (!iskeychar(c))
 127                         break;
 128                 name[len++] = tolower(c);
 129                 if (len >= MAXNAME)
 130                         return -1;
 131         }
 132         name[len] = 0;
 133         while (c == ' ' || c == '\t')
 134                 c = get_next_char();
 135
 136         value = NULL;
 137         if (c != '\n') {
 138                 if (c != '=')
 139                         return -1;
 140                 value = parse_value();
 141                 if (!value)
 142                         return -1;
 143         }
 144         return fn(name, value, data);
 145 }
 146
 147 static int get_extended_base_var(char *name, int baselen, int c)
 148 {
 149         do {
 150                 if (c == '\n')
 151                         return -1;
 152                 c = get_next_char();
 153         } while (isspace(c));
 154
 155         /* We require the format to be '[base "extension"]' */
 156         if (c != '"')
 157                 return -1;
 158         name[baselen++] = '.';
 159
 160         for (;;) {
 161                 int c = get_next_char();
 162                 if (c == '\n')
 163                         return -1;
 164                 if (c == '"')
 165                         break;
 166                 if (c == '\\') {
 167                         c = get_next_char();
 168                         if (c == '\n')
 169                                 return -1;
 170                 }
 171                 name[baselen++] = c;
 172                 if (baselen > MAXNAME / 2)
 173                         return -1;
 174         }
 175
 176         /* Final ']' */
 177         if (get_next_char() != ']')
 178                 return -1;
 179         return baselen;
 180 }
 181
 182 static int get_base_var(char *name)
 183 {
 184         int baselen = 0;
 185
 186         for (;;) {
 187                 int c = get_next_char();
 188                 if (config_file_eof)
 189                         return -1;
 190                 if (c == ']')
 191                         return baselen;
 192                 if (isspace(c))
 193                         return get_extended_base_var(name, baselen, c);
 194                 if (!iskeychar(c) && c != '.')
 195                         return -1;
 196                 if (baselen > MAXNAME / 2)
 197                         return -1;
 198                 name[baselen++] = tolower(c);
 199         }
 200 }
 201
 202 static int git_parse_file(config_fn_t fn, void *data)
 203 {
 204         int comment = 0;
 205         int baselen = 0;
 206         static char var[MAXNAME];
 207
 208         /* U+FEFF Byte Order Mark in UTF8 */
 209         static const unsigned char *utf8_bom = (unsigned char *) "\xef\xbb\xbf";
 210         const unsigned char *bomptr = utf8_bom;
 211
 212         for (;;) {
 213                 int c = get_next_char();
 214                 if (bomptr && *bomptr) {
 215                         /* We are at the file beginning; skip UTF8-encoded BOM
 216                          * if present. Sane editors won't put this in on their
 217                          * own, but e.g. Windows Notepad will do it happily. */
 218                         if ((unsigned char) c == *bomptr) {
 219                                 bomptr++;
 220                                 continue;
 221                         } else {
 222                                 /* Do not tolerate partial BOM. */
 223                                 if (bomptr != utf8_bom)
 224                                         break;
 225                                 /* No BOM at file beginning. Cool. */
 226                                 bomptr = NULL;
 227                         }
 228                 }
 229                 if (c == '\n') {
 230                         if (config_file_eof)
 231                                 return 0;
 232                         comment = 0;
 233                         continue;
 234                 }
 235                 if (comment || isspace(c))
 236                         continue;
 237                 if (c == '#' || c == ';') {
 238                         comment = 1;
 239                         continue;
 240                 }
 241                 if (c == '[') {
 242                         baselen = get_base_var(var);
 243                         if (baselen <= 0)
 244                                 break;
 245                         var[baselen++] = '.';
 246                         var[baselen] = 0;
 247                         continue;
 248                 }
 249                 if (!isalpha(c))
 250                         break;
 251                 var[baselen] = tolower(c);
 252                 if (get_value(fn, data, var, baselen+1) < 0)
 253                         break;
 254         }
 255         die("bad config file line %d in %s", config_linenr, config_file_name);
 256 }
 257
 258 static int parse_unit_factor(const char *end, unsigned long *val)
 259 {
 260         if (!*end)
 261                 return 1;
 262         else if (!strcasecmp(end, "k")) {
 263                 *val *= 1024;
 264                 return 1;
 265         }
 266         else if (!strcasecmp(end, "m")) {
 267                 *val *= 1024 * 1024;
 268                 return 1;
 269         }
 270         else if (!strcasecmp(end, "g")) {
 271                 *val *= 1024 * 1024 * 1024;
 272                 return 1;
 273         }
 274         return 0;
 275 }
 276
 277 static int git_parse_long(const char *value, long *ret)
 278 {
 279         if (value && *value) {
 280                 char *end;
 281                 long val = strtol(value, &end, 0);
 282                 unsigned long factor = 1;
 283                 if (!parse_unit_factor(end, &factor))
 284                         return 0;
 285                 *ret = val * factor;
 286                 return 1;
 287         }
 288         return 0;
 289 }
 290
 291 int git_parse_ulong(const char *value, unsigned long *ret)
 292 {
 293         if (value && *value) {
 294                 char *end;
 295                 unsigned long val = strtoul(value, &end, 0);
 296                 if (!parse_unit_factor(end, &val))
 297                         return 0;
 298                 *ret = val;
 299                 return 1;
 300         }
 301         return 0;
 302 }
 303
 304 static void die_bad_config(const char *name)
 305 {
 306         if (config_file_name)
 307                 die("bad config value for '%s' in %s", name, config_file_name);
 308         die("bad config value for '%s'", name);
 309 }
 310
 311 int git_config_int(const char *name, const char *value)
 312 {
 313         long ret = 0;
 314         if (!git_parse_long(value, &ret))
 315                 die_bad_config(name);
 316         return ret;
 317 }
 318
 319 unsigned long git_config_ulong(const char *name, const char *value)
 320 {
 321         unsigned long ret;
 322         if (!git_parse_ulong(value, &ret))
 323                 die_bad_config(name);
 324         return ret;
 325 }
 326
 327 int git_config_bool_or_int(const char *name, const char *value, int *is_bool)
 328 {
 329         *is_bool = 1;
 330         if (!value)
 331                 return 1;
 332         if (!*value)
 333                 return 0;
 334         if (!strcasecmp(value, "true") || !strcasecmp(value, "yes") || !strcasecmp(value, "on"))
 335                 return 1;
 336         if (!strcasecmp(value, "false") || !strcasecmp(value, "no") || !strcasecmp(value, "off"))
 337                 return 0;
 338         *is_bool = 0;
 339         return git_config_int(name, value);
 340 }
 341
 342 int git_config_bool(const char *name, const char *value)
 343 {
 344         int discard;
 345         return !!git_config_bool_or_int(name, value, &discard);
 346 }
 347
 348 int git_config_string(const char **dest, const char *var, const char *value)
 349 {
 350         if (!value)
 351                 return config_error_nonbool(var);
 352         *dest = xstrdup(value);
 353         return 0;
 354 }
 355
 356 static int git_default_core_config(const char *var, const char *value)
 357 {
 358         /* This needs a better name */
 359         if (!strcmp(var, "core.filemode")) {
 360                 trust_executable_bit = git_config_bool(var, value);
 361                 return 0;
 362         }
 363         if (!strcmp(var, "core.trustctime")) {
 364                 trust_ctime = git_config_bool(var, value);
 365                 return 0;
 366         }
 367
 368         if (!strcmp(var, "core.quotepath")) {
 369                 quote_path_fully = git_config_bool(var, value);
 370                 return 0;
 371         }
 372
 373         if (!strcmp(var, "core.symlinks")) {
 374                 has_symlinks = git_config_bool(var, value);
 375                 return 0;
 376         }
 377
 378         if (!strcmp(var, "core.ignorecase")) {
 379                 ignore_case = git_config_bool(var, value);
 380                 return 0;
 381         }
 382
 383         if (!strcmp(var, "core.bare")) {
 384                 is_bare_repository_cfg = git_config_bool(var, value);
 385                 return 0;
 386         }
 387
 388         if (!strcmp(var, "core.ignorestat")) {
 389                 assume_unchanged = git_config_bool(var, value);
 390                 return 0;
 391         }
 392
 393         if (!strcmp(var, "core.prefersymlinkrefs")) {
 394                 prefer_symlink_refs = git_config_bool(var, value);
 395                 return 0;
 396         }
 397
 398         if (!strcmp(var, "core.logallrefupdates")) {
 399                 log_all_ref_updates = git_config_bool(var, value);
 400                 return 0;
 401         }
 402
 403         if (!strcmp(var, "core.warnambiguousrefs")) {
 404                 warn_ambiguous_refs = git_config_bool(var, value);
 405                 return 0;
 406         }
 407
 408         if (!strcmp(var, "core.loosecompression")) {
 409                 int level = git_config_int(var, value);
 410                 if (level == -1)
 411                         level = Z_DEFAULT_COMPRESSION;
 412                 else if (level < 0 || level > Z_BEST_COMPRESSION)
 413                         die("bad zlib compression level %d", level);
 414                 zlib_compression_level = level;
 415                 zlib_compression_seen = 1;
 416                 return 0;
 417         }
 418
 419         if (!strcmp(var, "core.compression")) {
 420                 int level = git_config_int(var, value);
 421                 if (level == -1)
 422                         level = Z_DEFAULT_COMPRESSION;
 423                 else if (level < 0 || level > Z_BEST_COMPRESSION)
 424                         die("bad zlib compression level %d", level);
 425                 core_compression_level = level;
 426                 core_compression_seen = 1;
 427                 if (!zlib_compression_seen)
 428                         zlib_compression_level = level;
 429                 return 0;
 430         }
 431
 432         if (!strcmp(var, "core.packedgitwindowsize")) {
 433                 int pgsz_x2 = getpagesize() * 2;
 434                 packed_git_window_size = git_config_int(var, value);
 435
 436                 /* This value must be multiple of (pagesize * 2) */
 437                 packed_git_window_size /= pgsz_x2;
 438                 if (packed_git_window_size < 1)
 439                         packed_git_window_size = 1;
 440                 packed_git_window_size *= pgsz_x2;
 441                 return 0;
 442         }
 443
 444         if (!strcmp(var, "core.packedgitlimit")) {
 445                 packed_git_limit = git_config_int(var, value);
 446                 return 0;
 447         }
 448
 449         if (!strcmp(var, "core.deltabasecachelimit")) {
 450                 delta_base_cache_limit = git_config_int(var, value);
 451                 return 0;
 452         }
 453
 454         if (!strcmp(var, "core.autocrlf")) {
 455                 if (value && !strcasecmp(value, "input")) {
 456                         auto_crlf = -1;
 457                         return 0;
 458                 }
 459                 auto_crlf = git_config_bool(var, value);
 460                 return 0;
 461         }
 462
 463         if (!strcmp(var, "core.safecrlf")) {
 464                 if (value && !strcasecmp(value, "warn")) {
 465                         safe_crlf = SAFE_CRLF_WARN;
 466                         return 0;
 467                 }
 468                 safe_crlf = git_config_bool(var, value);
 469                 return 0;
 470         }
 471
 472         if (!strcmp(var, "core.pager"))
 473                 return git_config_string(&pager_program, var, value);
 474
 475         if (!strcmp(var, "core.editor"))
 476                 return git_config_string(&editor_program, var, value);
 477
 478         if (!strcmp(var, "core.excludesfile"))
 479                 return git_config_string(&excludes_file, var, value);
 480
 481         if (!strcmp(var, "core.whitespace")) {
 482                 if (!value)
 483                         return config_error_nonbool(var);
 484                 whitespace_rule_cfg = parse_whitespace_rule(value);
 485                 return 0;
 486         }
 487
 488         if (!strcmp(var, "core.fsyncobjectfiles")) {
 489                 fsync_object_files = git_config_bool(var, value);
 490                 return 0;
 491         }
 492
 493         if (!strcmp(var, "core.preloadindex")) {
 494                 core_preload_index = git_config_bool(var, value);
 495                 return 0;
 496         }
 497
 498         if (!strcmp(var, "core.createobject")) {
 499                 if (!strcmp(value, "rename"))
 500                         object_creation_mode = OBJECT_CREATION_USES_RENAMES;
 501                 else if (!strcmp(value, "link"))
 502                         object_creation_mode = OBJECT_CREATION_USES_HARDLINKS;
 503                 else
 504                         die("Invalid mode for object creation: %s", value);
 505                 return 0;
 506         }
 507
 508         /* Add other config variables here and to Documentation/config.txt. */
 509         return 0;
 510 }
 511
 512 static int git_default_user_config(const char *var, const char *value)
 513 {
 514         if (!strcmp(var, "user.name")) {
 515                 if (!value)
 516                         return config_error_nonbool(var);
 517                 strlcpy(git_default_name, value, sizeof(git_default_name));
 518                 if (git_default_email[0])
 519                         user_ident_explicitly_given = 1;
 520                 return 0;
 521         }
 522
 523         if (!strcmp(var, "user.email")) {
 524                 if (!value)
 525                         return config_error_nonbool(var);
 526                 strlcpy(git_default_email, value, sizeof(git_default_email));
 527                 if (git_default_name[0])
 528                         user_ident_explicitly_given = 1;
 529                 return 0;
 530         }
 531
 532         /* Add other config variables here and to Documentation/config.txt. */
 533         return 0;
 534 }
 535
 536 static int git_default_i18n_config(const char *var, const char *value)
 537 {
 538         if (!strcmp(var, "i18n.commitencoding"))
 539                 return git_config_string(&git_commit_encoding, var, value);
 540
 541         if (!strcmp(var, "i18n.logoutputencoding"))
 542                 return git_config_string(&git_log_output_encoding, var, value);
 543
 544         /* Add other config variables here and to Documentation/config.txt. */
 545         return 0;
 546 }
 547
 548 int git_tracking_config(const char *var, const char *value, struct tracking_config *cfg)
 549 {
 550         var = strrchr (var, '.');
 551         if (!strcmp(var, ".autosetupmerge")) {
 552                 if (value && !strcasecmp(value, "always")) {
 553                         cfg->merge = BRANCH_TRACK_ALWAYS;
 554                         return 0;
 555                 }
 556                 cfg->merge = git_config_bool(var, value);
 557                 return 0;
 558         }
 559         if (!strcmp(var, ".autosetuppush")) {
 560                 cfg->push = git_config_bool(var, value);
 561                 return 0;
 562         }
 563         if (!strcmp(var, ".autosetuprebase")) {
 564                 if (!value)
 565                         value = "always";
 566                 cfg->rebase = AUTOREBASE_NEVER;
 567                 if (!strcmp(value, "never"))
 568                         ;
 569                 else if (!strcmp(value, "local"))
 570                         cfg->rebase = AUTOREBASE_LOCAL;
 571                 else if (!strcmp(value, "remote"))
 572                         cfg->rebase = AUTOREBASE_REMOTE;
 573                 else if (!strcmp(value, "always") ||
 574                          git_config_bool (var, value))
 575                         cfg->rebase = AUTOREBASE_ALWAYS;
 576                 return 0;
 577         }
 578
 579         /* Add other config variables here and to Documentation/config.txt. */
 580         return 0;
 581 }
 582
 583 static int git_default_branch_config(const char *var, const char *value)
 584 {
 585         int result;
 586
 587         if (!prefixcmp(var, "branch.")
 588             && !strchr (var + 7, '.')) {
 589                 result = git_tracking_config (var, value, &git_branch_track);
 590                 if (result)
 591                         return result;
 592         }
 593
 594         /* Add other config variables here and to Documentation/config.txt. */
 595         return 0;
 596 }
 597
 598 static int git_default_push_config(const char *var, const char *value)
 599 {
 600         if (!strcmp(var, "push.default")) {
 601                 if (!value)
 602                         return config_error_nonbool(var);
 603                 else if (!strcmp(value, "nothing"))
 604                         push_default = PUSH_DEFAULT_NOTHING;
 605                 else if (!strcmp(value, "matching"))
 606                         push_default = PUSH_DEFAULT_MATCHING;
 607                 else if (!strcmp(value, "tracking"))
 608                         push_default = PUSH_DEFAULT_TRACKING;
 609                 else if (!strcmp(value, "current"))
 610                         push_default = PUSH_DEFAULT_CURRENT;
 611                 else {
 612                         error("Malformed value for %s: %s", var, value);
 613                         return error("Must be one of nothing, matching, "
 614                                      "tracking or current.");
 615                 }
 616                 return 0;
 617         }
 618
 619         /* Add other config variables here and to Documentation/config.txt. */
 620         return 0;
 621 }
 622
 623 static int git_default_mailmap_config(const char *var, const char *value)
 624 {
 625         if (!strcmp(var, "mailmap.file"))
 626                 return git_config_string(&git_mailmap_file, var, value);
 627
 628         /* Add other config variables here and to Documentation/config.txt. */
 629         return 0;
 630 }
 631
 632 int git_default_config(const char *var, const char *value, void *dummy)
 633 {
 634         if (!prefixcmp(var, "core."))
 635                 return git_default_core_config(var, value);
 636
 637         if (!prefixcmp(var, "user."))
 638                 return git_default_user_config(var, value);
 639
 640         if (!prefixcmp(var, "i18n."))
 641                 return git_default_i18n_config(var, value);
 642
 643         if (!prefixcmp(var, "branch."))
 644                 return git_default_branch_config(var, value);
 645
 646         if (!prefixcmp(var, "push."))
 647                 return git_default_push_config(var, value);
 648
 649         if (!prefixcmp(var, "mailmap."))
 650                 return git_default_mailmap_config(var, value);
 651
 652         if (!strcmp(var, "pager.color") || !strcmp(var, "color.pager")) {
 653                 pager_use_color = git_config_bool(var,value);
 654                 return 0;
 655         }
 656
 657         /* Add other config variables here and to Documentation/config.txt. */
 658         return 0;
 659 }
 660
 661 int git_config_from_file(config_fn_t fn, const char *filename, void *data)
 662 {
 663         int ret;
 664         FILE *f = fopen(filename, "r");
 665
 666         ret = -1;
 667         if (f) {
 668                 config_file = f;
 669                 config_file_name = filename;
 670                 config_linenr = 1;
 671                 config_file_eof = 0;
 672                 ret = git_parse_file(fn, data);
 673                 fclose(f);
 674                 config_file_name = NULL;
 675         }
 676         return ret;
 677 }
 678
 679 const char *git_etc_gitconfig(void)
 680 {
 681         static const char *system_wide;
 682         if (!system_wide)
 683                 system_wide = system_path(ETC_GITCONFIG);
 684         return system_wide;
 685 }
 686
 687 static int git_env_bool(const char *k, int def)
 688 {
 689         const char *v = getenv(k);
 690         return v ? git_config_bool(k, v) : def;
 691 }
 692
 693 int git_config_system(void)
 694 {
 695         return !git_env_bool("GIT_CONFIG_NOSYSTEM", 0);
 696 }
 697
 698 int git_config_global(void)
 699 {
 700         return !git_env_bool("GIT_CONFIG_NOGLOBAL", 0);
 701 }
 702
 703 int git_config(config_fn_t fn, void *data)
 704 {
 705         int ret = 0, found = 0;
 706         char *repo_config = NULL;
 707         const char *home = NULL;
 708
 709         /* Setting $GIT_CONFIG makes git read _only_ the given config file. */
 710         if (config_exclusive_filename)
 711                 return git_config_from_file(fn, config_exclusive_filename, data);
 712         if (git_config_system() && !access(git_etc_gitconfig(), R_OK)) {
 713                 ret += git_config_from_file(fn, git_etc_gitconfig(),
 714                                             data);
 715                 found += 1;
 716         }
 717
 718         home = getenv("HOME");
 719         if (git_config_global() && home) {
 720                 char *user_config = xstrdup(mkpath("%s/.gitconfig", home));
 721                 if (!access(user_config, R_OK)) {
 722                         ret += git_config_from_file(fn, user_config, data);
 723                         found += 1;
 724                 }
 725                 free(user_config);
 726         }
 727
 728         repo_config = git_pathdup("config");
 729         if (!access(repo_config, R_OK)) {
 730                 ret += git_config_from_file(fn, repo_config, data);
 731                 found += 1;
 732         }
 733         free(repo_config);
 734         if (found == 0)
 735                 return -1;
 736         return ret;
 737 }
 738
 739 /*
 740  * Find all the stuff for git_config_set() below.
 741  */
 742
 743 #define MAX_MATCHES 512
 744
 745 static struct {
 746         int baselen;
 747         char *key;
 748         int do_not_match;
 749         regex_t *value_regex;
 750         int multi_replace;
 751         size_t offset[MAX_MATCHES];
 752         enum { START, SECTION_SEEN, SECTION_END_SEEN, KEY_SEEN } state;
 753         int seen;
 754 } store;
 755
 756 static int matches(const char *key, const char *value)
 757 {
 758         return !strcmp(key, store.key) &&
 759                 (store.value_regex == NULL ||
 760                  (store.do_not_match ^
 761                   !regexec(store.value_regex, value, 0, NULL, 0)));
 762 }
 763
 764 static int store_aux(const char *key, const char *value, void *cb)
 765 {
 766         const char *ep;
 767         size_t section_len;
 768
 769         switch (store.state) {
 770         case KEY_SEEN:
 771                 if (matches(key, value)) {
 772                         if (store.seen == 1 && store.multi_replace == 0) {
 773                                 warning("%s has multiple values", key);
 774                         } else if (store.seen >= MAX_MATCHES) {
 775                                 error("too many matches for %s", key);
 776                                 return 1;
 777                         }
 778
 779                         store.offset[store.seen] = ftell(config_file);
 780                         store.seen++;
 781                 }
 782                 break;
 783         case SECTION_SEEN:
 784                 /*
 785                  * What we are looking for is in store.key (both
 786                  * section and var), and its section part is baselen
 787                  * long.  We found key (again, both section and var).
 788                  * We would want to know if this key is in the same
 789                  * section as what we are looking for.  We already
 790                  * know we are in the same section as what should
 791                  * hold store.key.
 792                  */
 793                 ep = strrchr(key, '.');
 794                 section_len = ep - key;
 795
 796                 if ((section_len != store.baselen) ||
 797                     memcmp(key, store.key, section_len+1)) {
 798                         store.state = SECTION_END_SEEN;
 799                         break;
 800                 }
 801
 802                 /*
 803                  * Do not increment matches: this is no match, but we
 804                  * just made sure we are in the desired section.
 805                  */
 806                 store.offset[store.seen] = ftell(config_file);
 807                 /* fallthru */
 808         case SECTION_END_SEEN:
 809         case START:
 810                 if (matches(key, value)) {
 811                         store.offset[store.seen] = ftell(config_file);
 812                         store.state = KEY_SEEN;
 813                         store.seen++;
 814                 } else {
 815                         if (strrchr(key, '.') - key == store.baselen &&
 816                               !strncmp(key, store.key, store.baselen)) {
 817                                         store.state = SECTION_SEEN;
 818                                         store.offset[store.seen] = ftell(config_file);
 819                         }
 820                 }
 821         }
 822         return 0;
 823 }
 824
 825 static int write_error(const char *filename)
 826 {
 827         error("failed to write new configuration file %s", filename);
 828
 829         /* Same error code as "failed to rename". */
 830         return 4;
 831 }
 832
 833 static int store_write_section(int fd, const char *key)
 834 {
 835         const char *dot;
 836         int i, success;
 837         struct strbuf sb = STRBUF_INIT;
 838
 839         dot = memchr(key, '.', store.baselen);
 840         if (dot) {
 841                 strbuf_addf(&sb, "[%.*s \"", (int)(dot - key), key);
 842                 for (i = dot - key + 1; i < store.baselen; i++) {
 843                         if (key[i] == '"' || key[i] == '\\')
 844                                 strbuf_addch(&sb, '\\');
 845                         strbuf_addch(&sb, key[i]);
 846                 }
 847                 strbuf_addstr(&sb, "\"]\n");
 848         } else {
 849                 strbuf_addf(&sb, "[%.*s]\n", store.baselen, key);
 850         }
 851
 852         success = write_in_full(fd, sb.buf, sb.len) == sb.len;
 853         strbuf_release(&sb);
 854
 855         return success;
 856 }
 857
 858 static int store_write_pair(int fd, const char *key, const char *value)
 859 {
 860         int i, success;
 861         int length = strlen(key + store.baselen + 1);
 862         const char *quote = "";
 863         struct strbuf sb = STRBUF_INIT;
 864
 865         /*
 866          * Check to see if the value needs to be surrounded with a dq pair.
 867          * Note that problematic characters are always backslash-quoted; this
 868          * check is about not losing leading or trailing SP and strings that
 869          * follow beginning-of-comment characters (i.e. ';' and '#') by the
 870          * configuration parser.
 871          */
 872         if (value[0] == ' ')
 873                 quote = "\"";
 874         for (i = 0; value[i]; i++)
 875                 if (value[i] == ';' || value[i] == '#')
 876                         quote = "\"";
 877         if (i && value[i - 1] == ' ')
 878                 quote = "\"";
 879
 880         strbuf_addf(&sb, "\t%.*s = %s",
 881                     length, key + store.baselen + 1, quote);
 882
 883         for (i = 0; value[i]; i++)
 884                 switch (value[i]) {
 885                 case '\n':
 886                         strbuf_addstr(&sb, "\\n");
 887                         break;
 888                 case '\t':
 889                         strbuf_addstr(&sb, "\\t");
 890                         break;
 891                 case '"':
 892                 case '\\':
 893                         strbuf_addch(&sb, '\\');
 894                 default:
 895                         strbuf_addch(&sb, value[i]);
 896                         break;
 897                 }
 898         strbuf_addf(&sb, "%s\n", quote);
 899
 900         success = write_in_full(fd, sb.buf, sb.len) == sb.len;
 901         strbuf_release(&sb);
 902
 903         return success;
 904 }
 905
 906 static ssize_t find_beginning_of_line(const char *contents, size_t size,
 907         size_t offset_, int *found_bracket)
 908 {
 909         size_t equal_offset = size, bracket_offset = size;
 910         ssize_t offset;
 911
 912 contline:
 913         for (offset = offset_-2; offset > 0
 914                         && contents[offset] != '\n'; offset--)
 915                 switch (contents[offset]) {
 916                         case '=': equal_offset = offset; break;
 917                         case ']': bracket_offset = offset; break;
 918                 }
 919         if (offset > 0 && contents[offset-1] == '\\') {
 920                 offset_ = offset;
 921                 goto contline;
 922         }
 923         if (bracket_offset < equal_offset) {
 924                 *found_bracket = 1;
 925                 offset = bracket_offset+1;
 926         } else
 927                 offset++;
 928
 929         return offset;
 930 }
 931
 932 int git_config_set(const char *key, const char *value)
 933 {
 934         return git_config_set_multivar(key, value, NULL, 0);
 935 }
 936
 937 /*
 938  * If value==NULL, unset in (remove from) config,
 939  * if value_regex!=NULL, disregard key/value pairs where value does not match.
 940  * if multi_replace==0, nothing, or only one matching key/value is replaced,
 941  *     else all matching key/values (regardless how many) are removed,
 942  *     before the new pair is written.
 943  *
 944  * Returns 0 on success.
 945  *
 946  * This function does this:
 947  *
 948  * - it locks the config file by creating ".git/config.lock"
 949  *
 950  * - it then parses the config using store_aux() as validator to find
 951  *   the position on the key/value pair to replace. If it is to be unset,
 952  *   it must be found exactly once.
 953  *
 954  * - the config file is mmap()ed and the part before the match (if any) is
 955  *   written to the lock file, then the changed part and the rest.
 956  *
 957  * - the config file is removed and the lock file rename()d to it.
 958  *
 959  */
 960 int git_config_set_multivar(const char *key, const char *value,
 961         const char *value_regex, int multi_replace)
 962 {
 963         int i, dot;
 964         int fd = -1, in_fd;
 965         int ret;
 966         char *config_filename;
 967         struct lock_file *lock = NULL;
 968         const char *last_dot = strrchr(key, '.');
 969
 970         if (config_exclusive_filename)
 971                 config_filename = xstrdup(config_exclusive_filename);
 972         else
 973                 config_filename = git_pathdup("config");
 974
 975         /*
 976          * Since "key" actually contains the section name and the real
 977          * key name separated by a dot, we have to know where the dot is.
 978          */
 979
 980         if (last_dot == NULL) {
 981                 error("key does not contain a section: %s", key);
 982                 ret = 2;
 983                 goto out_free;
 984         }
 985         store.baselen = last_dot - key;
 986
 987         store.multi_replace = multi_replace;
 988
 989         /*
 990          * Validate the key and while at it, lower case it for matching.
 991          */
 992         store.key = xmalloc(strlen(key) + 1);
 993         dot = 0;
 994         for (i = 0; key[i]; i++) {
 995                 unsigned char c = key[i];
 996                 if (c == '.')
 997                         dot = 1;
 998                 /* Leave the extended basename untouched.. */
 999                 if (!dot || i > store.baselen) {
1000                         if (!iskeychar(c) || (i == store.baselen+1 && !isalpha(c))) {
1001                                 error("invalid key: %s", key);
1002                                 free(store.key);
1003                                 ret = 1;
1004                                 goto out_free;
1005                         }
1006                         c = tolower(c);
1007                 } else if (c == '\n') {
1008                         error("invalid key (newline): %s", key);
1009                         free(store.key);
1010                         ret = 1;
1011                         goto out_free;
1012                 }
1013                 store.key[i] = c;
1014         }
1015         store.key[i] = 0;
1016
1017         /*
1018          * The lock serves a purpose in addition to locking: the new
1019          * contents of .git/config will be written into it.
1020          */
1021         lock = xcalloc(sizeof(struct lock_file), 1);
1022         fd = hold_lock_file_for_update(lock, config_filename, 0);
1023         if (fd < 0) {
1024                 error("could not lock config file %s: %s", config_filename, strerror(errno));
1025                 free(store.key);
1026                 ret = -1;
1027                 goto out_free;
1028         }
1029
1030         /*
1031          * If .git/config does not exist yet, write a minimal version.
1032          */
1033         in_fd = open(config_filename, O_RDONLY);
1034         if ( in_fd < 0 ) {
1035                 free(store.key);
1036
1037                 if ( ENOENT != errno ) {
1038                         error("opening %s: %s", config_filename,
1039                               strerror(errno));
1040                         ret = 3; /* same as "invalid config file" */
1041                         goto out_free;
1042                 }
1043                 /* if nothing to unset, error out */
1044                 if (value == NULL) {
1045                         ret = 5;
1046                         goto out_free;
1047                 }
1048
1049                 store.key = (char *)key;
1050                 if (!store_write_section(fd, key) ||
1051                     !store_write_pair(fd, key, value))
1052                         goto write_err_out;
1053         } else {
1054                 struct stat st;
1055                 char *contents;
1056                 size_t contents_sz, copy_begin, copy_end;
1057                 int i, new_line = 0;
1058
1059                 if (value_regex == NULL)
1060                         store.value_regex = NULL;
1061                 else {
1062                         if (value_regex[0] == '!') {
1063                                 store.do_not_match = 1;
1064                                 value_regex++;
1065                         } else
1066                                 store.do_not_match = 0;
1067
1068                         store.value_regex = (regex_t*)xmalloc(sizeof(regex_t));
1069                         if (regcomp(store.value_regex, value_regex,
1070                                         REG_EXTENDED)) {
1071                                 error("invalid pattern: %s", value_regex);
1072                                 free(store.value_regex);
1073                                 ret = 6;
1074                                 goto out_free;
1075                         }
1076                 }
1077
1078                 store.offset[0] = 0;
1079                 store.state = START;
1080                 store.seen = 0;
1081
1082                 /*
1083                  * After this, store.offset will contain the *end* offset
1084                  * of the last match, or remain at 0 if no match was found.
1085                  * As a side effect, we make sure to transform only a valid
1086                  * existing config file.
1087                  */
1088                 if (git_config_from_file(store_aux, config_filename, NULL)) {
1089                         error("invalid config file %s", config_filename);
1090                         free(store.key);
1091                         if (store.value_regex != NULL) {
1092                                 regfree(store.value_regex);
1093                                 free(store.value_regex);
1094                         }
1095                         ret = 3;
1096                         goto out_free;
1097                 }
1098
1099                 free(store.key);
1100                 if (store.value_regex != NULL) {
1101                         regfree(store.value_regex);
1102                         free(store.value_regex);
1103                 }
1104
1105                 /* if nothing to unset, or too many matches, error out */
1106                 if ((store.seen == 0 && value == NULL) ||
1107                                 (store.seen > 1 && multi_replace == 0)) {
1108                         ret = 5;
1109                         goto out_free;
1110                 }
1111
1112                 fstat(in_fd, &st);
1113                 contents_sz = xsize_t(st.st_size);
1114                 contents = xmmap(NULL, contents_sz, PROT_READ,
1115                         MAP_PRIVATE, in_fd, 0);
1116                 close(in_fd);
1117
1118                 if (store.seen == 0)
1119                         store.seen = 1;
1120
1121                 for (i = 0, copy_begin = 0; i < store.seen; i++) {
1122                         if (store.offset[i] == 0) {
1123                                 store.offset[i] = copy_end = contents_sz;
1124                         } else if (store.state != KEY_SEEN) {
1125                                 copy_end = store.offset[i];
1126                         } else
1127                                 copy_end = find_beginning_of_line(
1128                                         contents, contents_sz,
1129                                         store.offset[i]-2, &new_line);
1130
1131                         if (copy_end > 0 && contents[copy_end-1] != '\n')
1132                                 new_line = 1;
1133
1134                         /* write the first part of the config */
1135                         if (copy_end > copy_begin) {
1136                                 if (write_in_full(fd, contents + copy_begin,
1137                                                   copy_end - copy_begin) <
1138                                     copy_end - copy_begin)
1139                                         goto write_err_out;
1140                                 if (new_line &&
1141                                     write_in_full(fd, "\n", 1) != 1)
1142                                         goto write_err_out;
1143                         }
1144                         copy_begin = store.offset[i];
1145                 }
1146
1147                 /* write the pair (value == NULL means unset) */
1148                 if (value != NULL) {
1149                         if (store.state == START) {
1150                                 if (!store_write_section(fd, key))
1151                                         goto write_err_out;
1152                         }
1153                         if (!store_write_pair(fd, key, value))
1154                                 goto write_err_out;
1155                 }
1156
1157                 /* write the rest of the config */
1158                 if (copy_begin < contents_sz)
1159                         if (write_in_full(fd, contents + copy_begin,
1160                                           contents_sz - copy_begin) <
1161                             contents_sz - copy_begin)
1162                                 goto write_err_out;
1163
1164                 munmap(contents, contents_sz);
1165         }
1166
1167         if (commit_lock_file(lock) < 0) {
1168                 error("could not commit config file %s", config_filename);
1169                 ret = 4;
1170                 goto out_free;
1171         }
1172
1173         /*
1174          * lock is committed, so don't try to roll it back below.
1175          * NOTE: Since lockfile.c keeps a linked list of all created
1176          * lock_file structures, it isn't safe to free(lock).  It's
1177          * better to just leave it hanging around.
1178          */
1179         lock = NULL;
1180         ret = 0;
1181
1182 out_free:
1183         if (lock)
1184                 rollback_lock_file(lock);
1185         free(config_filename);
1186         return ret;
1187
1188 write_err_out:
1189         ret = write_error(lock->filename);
1190         goto out_free;
1191
1192 }
1193
1194 static int section_name_match (const char *buf, const char *name)
1195 {
1196         int i = 0, j = 0, dot = 0;
1197         for (; buf[i] && buf[i] != ']'; i++) {
1198                 if (!dot && isspace(buf[i])) {
1199                         dot = 1;
1200                         if (name[j++] != '.')
1201                                 break;
1202                         for (i++; isspace(buf[i]); i++)
1203                                 ; /* do nothing */
1204                         if (buf[i] != '"')
1205                                 break;
1206                         continue;
1207                 }
1208                 if (buf[i] == '\\' && dot)
1209                         i++;
1210                 else if (buf[i] == '"' && dot) {
1211                         for (i++; isspace(buf[i]); i++)
1212                                 ; /* do_nothing */
1213                         break;
1214                 }
1215                 if (buf[i] != name[j++])
1216                         break;
1217         }
1218         return (buf[i] == ']' && name[j] == 0);
1219 }
1220
1221 /* if new_name == NULL, the section is removed instead */
1222 int git_config_rename_section(const char *old_name, const char *new_name)
1223 {
1224         int ret = 0, remove = 0;
1225         char *config_filename;
1226         struct lock_file *lock = xcalloc(sizeof(struct lock_file), 1);
1227         int out_fd;
1228         char buf[1024];
1229
1230         if (config_exclusive_filename)
1231                 config_filename = xstrdup(config_exclusive_filename);
1232         else
1233                 config_filename = git_pathdup("config");
1234         out_fd = hold_lock_file_for_update(lock, config_filename, 0);
1235         if (out_fd < 0) {
1236                 ret = error("could not lock config file %s", config_filename);
1237                 goto out;
1238         }
1239
1240         if (!(config_file = fopen(config_filename, "rb"))) {
1241                 /* no config file means nothing to rename, no error */
1242                 goto unlock_and_out;
1243         }
1244
1245         while (fgets(buf, sizeof(buf), config_file)) {
1246                 int i;
1247                 int length;
1248                 for (i = 0; buf[i] && isspace(buf[i]); i++)
1249                         ; /* do nothing */
1250                 if (buf[i] == '[') {
1251                         /* it's a section */
1252                         if (section_name_match (&buf[i+1], old_name)) {
1253                                 ret++;
1254                                 if (new_name == NULL) {
1255                                         remove = 1;
1256                                         continue;
1257                                 }
1258                                 store.baselen = strlen(new_name);
1259                                 if (!store_write_section(out_fd, new_name)) {
1260                                         ret = write_error(lock->filename);
1261                                         goto out;
1262                                 }
1263                                 continue;
1264                         }
1265                         remove = 0;
1266                 }
1267                 if (remove)
1268                         continue;
1269                 length = strlen(buf);
1270                 if (write_in_full(out_fd, buf, length) != length) {
1271                         ret = write_error(lock->filename);
1272                         goto out;
1273                 }
1274         }
1275         fclose(config_file);
1276  unlock_and_out:
1277         if (commit_lock_file(lock) < 0)
1278                 ret = error("could not commit config file %s", config_filename);
1279  out:
1280         free(config_filename);
1281         return ret;
1282 }
1283
1284 /*
1285  * Call this to report error for your variable that should not
1286  * get a boolean value (i.e. "[my] var" means "true").
1287  */
1288 int config_error_nonbool(const char *var)
1289 {
1290         return error("Missing value for '%s'", var);
1291 }