config.c

   1 /*
   2  * GIT - The information manager from hell
   3  *
   4  * Copyright (C) Linus Torvalds, 2005
   5  * Copyright (C) Johannes Schindelin, 2005
   6  *
   7  */
   8 #include "cache.h"
   9 #include "exec_cmd.h"
  10
  11 #define MAXNAME (256)
  12
  13 static FILE *config_file;
  14 static const char *config_file_name;
  15 static int config_linenr;
  16 static int config_file_eof;
  17 static int zlib_compression_seen;
  18
  19 const char *config_exclusive_filename = NULL;
  20
  21 static int get_next_char(void)
  22 {
  23         int c;
  24         FILE *f;
  25
  26         c = '\n';
  27         if ((f = config_file) != NULL) {
  28                 c = fgetc(f);
  29                 if (c == '\r') {
  30                         /* DOS like systems */
  31                         c = fgetc(f);
  32                         if (c != '\n') {
  33                                 ungetc(c, f);
  34                                 c = '\r';
  35                         }
  36                 }
  37                 if (c == '\n')
  38                         config_linenr++;
  39                 if (c == EOF) {
  40                         config_file_eof = 1;
  41                         c = '\n';
  42                 }
  43         }
  44         return c;
  45 }
  46
  47 static char *parse_value(void)
  48 {
  49         static char value[1024];
  50         int quote = 0, comment = 0, len = 0, space = 0;
  51
  52         for (;;) {
  53                 int c = get_next_char();
  54                 if (len >= sizeof(value) - 1)
  55                         return NULL;
  56                 if (c == '\n') {
  57                         if (quote)
  58                                 return NULL;
  59                         value[len] = 0;
  60                         return value;
  61                 }
  62                 if (comment)
  63                         continue;
  64                 if (isspace(c) && !quote) {
  65                         if (len)
  66                                 space++;
  67                         continue;
  68                 }
  69                 if (!quote) {
  70                         if (c == ';' || c == '#') {
  71                                 comment = 1;
  72                                 continue;
  73                         }
  74                 }
  75                 for (; space; space--)
  76                         value[len++] = ' ';
  77                 if (c == '\\') {
  78                         c = get_next_char();
  79                         switch (c) {
  80                         case '\n':
  81                                 continue;
  82                         case 't':
  83                                 c = '\t';
  84                                 break;
  85                         case 'b':
  86                                 c = '\b';
  87                                 break;
  88                         case 'n':
  89                                 c = '\n';
  90                                 break;
  91                         /* Some characters escape as themselves */
  92                         case '\\': case '"':
  93                                 break;
  94                         /* Reject unknown escape sequences */
  95                         default:
  96                                 return NULL;
  97                         }
  98                         value[len++] = c;
  99                         continue;
 100                 }
 101                 if (c == '"') {
 102                         quote = 1-quote;
 103                         continue;
 104                 }
 105                 value[len++] = c;
 106         }
 107 }
 108
 109 static inline int iskeychar(int c)
 110 {
 111         return isalnum(c) || c == '-';
 112 }
 113
 114 static int get_value(config_fn_t fn, void *data, char *name, unsigned int len)
 115 {
 116         int c;
 117         char *value;
 118
 119         /* Get the full name */
 120         for (;;) {
 121                 c = get_next_char();
 122                 if (config_file_eof)
 123                         break;
 124                 if (!iskeychar(c))
 125                         break;
 126                 name[len++] = tolower(c);
 127                 if (len >= MAXNAME)
 128                         return -1;
 129         }
 130         name[len] = 0;
 131         while (c == ' ' || c == '\t')
 132                 c = get_next_char();
 133
 134         value = NULL;
 135         if (c != '\n') {
 136                 if (c != '=')
 137                         return -1;
 138                 value = parse_value();
 139                 if (!value)
 140                         return -1;
 141         }
 142         return fn(name, value, data);
 143 }
 144
 145 static int get_extended_base_var(char *name, int baselen, int c)
 146 {
 147         do {
 148                 if (c == '\n')
 149                         return -1;
 150                 c = get_next_char();
 151         } while (isspace(c));
 152
 153         /* We require the format to be '[base "extension"]' */
 154         if (c != '"')
 155                 return -1;
 156         name[baselen++] = '.';
 157
 158         for (;;) {
 159                 int c = get_next_char();
 160                 if (c == '\n')
 161                         return -1;
 162                 if (c == '"')
 163                         break;
 164                 if (c == '\\') {
 165                         c = get_next_char();
 166                         if (c == '\n')
 167                                 return -1;
 168                 }
 169                 name[baselen++] = c;
 170                 if (baselen > MAXNAME / 2)
 171                         return -1;
 172         }
 173
 174         /* Final ']' */
 175         if (get_next_char() != ']')
 176                 return -1;
 177         return baselen;
 178 }
 179
 180 static int get_base_var(char *name)
 181 {
 182         int baselen = 0;
 183
 184         for (;;) {
 185                 int c = get_next_char();
 186                 if (config_file_eof)
 187                         return -1;
 188                 if (c == ']')
 189                         return baselen;
 190                 if (isspace(c))
 191                         return get_extended_base_var(name, baselen, c);
 192                 if (!iskeychar(c) && c != '.')
 193                         return -1;
 194                 if (baselen > MAXNAME / 2)
 195                         return -1;
 196                 name[baselen++] = tolower(c);
 197         }
 198 }
 199
 200 static int git_parse_file(config_fn_t fn, void *data)
 201 {
 202         int comment = 0;
 203         int baselen = 0;
 204         static char var[MAXNAME];
 205
 206         /* U+FEFF Byte Order Mark in UTF8 */
 207         static const unsigned char *utf8_bom = (unsigned char *) "\xef\xbb\xbf";
 208         const unsigned char *bomptr = utf8_bom;
 209
 210         for (;;) {
 211                 int c = get_next_char();
 212                 if (bomptr && *bomptr) {
 213                         /* We are at the file beginning; skip UTF8-encoded BOM
 214                          * if present. Sane editors won't put this in on their
 215                          * own, but e.g. Windows Notepad will do it happily. */
 216                         if ((unsigned char) c == *bomptr) {
 217                                 bomptr++;
 218                                 continue;
 219                         } else {
 220                                 /* Do not tolerate partial BOM. */
 221                                 if (bomptr != utf8_bom)
 222                                         break;
 223                                 /* No BOM at file beginning. Cool. */
 224                                 bomptr = NULL;
 225                         }
 226                 }
 227                 if (c == '\n') {
 228                         if (config_file_eof)
 229                                 return 0;
 230                         comment = 0;
 231                         continue;
 232                 }
 233                 if (comment || isspace(c))
 234                         continue;
 235                 if (c == '#' || c == ';') {
 236                         comment = 1;
 237                         continue;
 238                 }
 239                 if (c == '[') {
 240                         baselen = get_base_var(var);
 241                         if (baselen <= 0)
 242                                 break;
 243                         var[baselen++] = '.';
 244                         var[baselen] = 0;
 245                         continue;
 246                 }
 247                 if (!isalpha(c))
 248                         break;
 249                 var[baselen] = tolower(c);
 250                 if (get_value(fn, data, var, baselen+1) < 0)
 251                         break;
 252         }
 253         die("bad config file line %d in %s", config_linenr, config_file_name);
 254 }
 255
 256 static int parse_unit_factor(const char *end, unsigned long *val)
 257 {
 258         if (!*end)
 259                 return 1;
 260         else if (!strcasecmp(end, "k")) {
 261                 *val *= 1024;
 262                 return 1;
 263         }
 264         else if (!strcasecmp(end, "m")) {
 265                 *val *= 1024 * 1024;
 266                 return 1;
 267         }
 268         else if (!strcasecmp(end, "g")) {
 269                 *val *= 1024 * 1024 * 1024;
 270                 return 1;
 271         }
 272         return 0;
 273 }
 274
 275 static int git_parse_long(const char *value, long *ret)
 276 {
 277         if (value && *value) {
 278                 char *end;
 279                 long val = strtol(value, &end, 0);
 280                 unsigned long factor = 1;
 281                 if (!parse_unit_factor(end, &factor))
 282                         return 0;
 283                 *ret = val * factor;
 284                 return 1;
 285         }
 286         return 0;
 287 }
 288
 289 int git_parse_ulong(const char *value, unsigned long *ret)
 290 {
 291         if (value && *value) {
 292                 char *end;
 293                 unsigned long val = strtoul(value, &end, 0);
 294                 if (!parse_unit_factor(end, &val))
 295                         return 0;
 296                 *ret = val;
 297                 return 1;
 298         }
 299         return 0;
 300 }
 301
 302 static void die_bad_config(const char *name)
 303 {
 304         if (config_file_name)
 305                 die("bad config value for '%s' in %s", name, config_file_name);
 306         die("bad config value for '%s'", name);
 307 }
 308
 309 int git_config_int(const char *name, const char *value)
 310 {
 311         long ret = 0;
 312         if (!git_parse_long(value, &ret))
 313                 die_bad_config(name);
 314         return ret;
 315 }
 316
 317 unsigned long git_config_ulong(const char *name, const char *value)
 318 {
 319         unsigned long ret;
 320         if (!git_parse_ulong(value, &ret))
 321                 die_bad_config(name);
 322         return ret;
 323 }
 324
 325 int git_config_bool_or_int(const char *name, const char *value, int *is_bool)
 326 {
 327         *is_bool = 1;
 328         if (!value)
 329                 return 1;
 330         if (!*value)
 331                 return 0;
 332         if (!strcasecmp(value, "true") || !strcasecmp(value, "yes") || !strcasecmp(value, "on"))
 333                 return 1;
 334         if (!strcasecmp(value, "false") || !strcasecmp(value, "no") || !strcasecmp(value, "off"))
 335                 return 0;
 336         *is_bool = 0;
 337         return git_config_int(name, value);
 338 }
 339
 340 int git_config_bool(const char *name, const char *value)
 341 {
 342         int discard;
 343         return !!git_config_bool_or_int(name, value, &discard);
 344 }
 345
 346 int git_config_string(const char **dest, const char *var, const char *value)
 347 {
 348         if (!value)
 349                 return config_error_nonbool(var);
 350         *dest = xstrdup(value);
 351         return 0;
 352 }
 353
 354 int git_config_pathname(const char **dest, const char *var, const char *value)
 355 {
 356         if (!value)
 357                 return config_error_nonbool(var);
 358         *dest = expand_user_path(value);
 359         if (!*dest)
 360                 die("Failed to expand user dir in: '%s'", value);
 361         return 0;
 362 }
 363
 364 static int git_default_core_config(const char *var, const char *value)
 365 {
 366         /* This needs a better name */
 367         if (!strcmp(var, "core.filemode")) {
 368                 trust_executable_bit = git_config_bool(var, value);
 369                 return 0;
 370         }
 371         if (!strcmp(var, "core.trustctime")) {
 372                 trust_ctime = git_config_bool(var, value);
 373                 return 0;
 374         }
 375
 376         if (!strcmp(var, "core.quotepath")) {
 377                 quote_path_fully = git_config_bool(var, value);
 378                 return 0;
 379         }
 380
 381         if (!strcmp(var, "core.symlinks")) {
 382                 has_symlinks = git_config_bool(var, value);
 383                 return 0;
 384         }
 385
 386         if (!strcmp(var, "core.ignorecase")) {
 387                 ignore_case = git_config_bool(var, value);
 388                 return 0;
 389         }
 390
 391         if (!strcmp(var, "core.bare")) {
 392                 is_bare_repository_cfg = git_config_bool(var, value);
 393                 return 0;
 394         }
 395
 396         if (!strcmp(var, "core.ignorestat")) {
 397                 assume_unchanged = git_config_bool(var, value);
 398                 return 0;
 399         }
 400
 401         if (!strcmp(var, "core.prefersymlinkrefs")) {
 402                 prefer_symlink_refs = git_config_bool(var, value);
 403                 return 0;
 404         }
 405
 406         if (!strcmp(var, "core.logallrefupdates")) {
 407                 log_all_ref_updates = git_config_bool(var, value);
 408                 return 0;
 409         }
 410
 411         if (!strcmp(var, "core.warnambiguousrefs")) {
 412                 warn_ambiguous_refs = git_config_bool(var, value);
 413                 return 0;
 414         }
 415
 416         if (!strcmp(var, "core.loosecompression")) {
 417                 int level = git_config_int(var, value);
 418                 if (level == -1)
 419                         level = Z_DEFAULT_COMPRESSION;
 420                 else if (level < 0 || level > Z_BEST_COMPRESSION)
 421                         die("bad zlib compression level %d", level);
 422                 zlib_compression_level = level;
 423                 zlib_compression_seen = 1;
 424                 return 0;
 425         }
 426
 427         if (!strcmp(var, "core.compression")) {
 428                 int level = git_config_int(var, value);
 429                 if (level == -1)
 430                         level = Z_DEFAULT_COMPRESSION;
 431                 else if (level < 0 || level > Z_BEST_COMPRESSION)
 432                         die("bad zlib compression level %d", level);
 433                 core_compression_level = level;
 434                 core_compression_seen = 1;
 435                 if (!zlib_compression_seen)
 436                         zlib_compression_level = level;
 437                 return 0;
 438         }
 439
 440         if (!strcmp(var, "core.packedgitwindowsize")) {
 441                 int pgsz_x2 = getpagesize() * 2;
 442                 packed_git_window_size = git_config_int(var, value);
 443
 444                 /* This value must be multiple of (pagesize * 2) */
 445                 packed_git_window_size /= pgsz_x2;
 446                 if (packed_git_window_size < 1)
 447                         packed_git_window_size = 1;
 448                 packed_git_window_size *= pgsz_x2;
 449                 return 0;
 450         }
 451
 452         if (!strcmp(var, "core.packedgitlimit")) {
 453                 packed_git_limit = git_config_int(var, value);
 454                 return 0;
 455         }
 456
 457         if (!strcmp(var, "core.deltabasecachelimit")) {
 458                 delta_base_cache_limit = git_config_int(var, value);
 459                 return 0;
 460         }
 461
 462         if (!strcmp(var, "core.autocrlf")) {
 463                 if (value && !strcasecmp(value, "input")) {
 464                         if (eol == EOL_CRLF)
 465                                 return error("core.autocrlf=input conflicts with core.eol=crlf");
 466                         auto_crlf = AUTO_CRLF_INPUT;
 467                         return 0;
 468                 }
 469                 auto_crlf = git_config_bool(var, value);
 470                 return 0;
 471         }
 472
 473         if (!strcmp(var, "core.safecrlf")) {
 474                 if (value && !strcasecmp(value, "warn")) {
 475                         safe_crlf = SAFE_CRLF_WARN;
 476                         return 0;
 477                 }
 478                 safe_crlf = git_config_bool(var, value);
 479                 return 0;
 480         }
 481
 482         if (!strcmp(var, "core.eol")) {
 483                 if (value && !strcasecmp(value, "lf"))
 484                         eol = EOL_LF;
 485                 else if (value && !strcasecmp(value, "crlf"))
 486                         eol = EOL_CRLF;
 487                 else if (value && !strcasecmp(value, "native"))
 488                         eol = EOL_NATIVE;
 489                 else
 490                         eol = EOL_UNSET;
 491                 if (eol == EOL_CRLF && auto_crlf == AUTO_CRLF_INPUT)
 492                         return error("core.autocrlf=input conflicts with core.eol=crlf");
 493                 return 0;
 494         }
 495
 496         if (!strcmp(var, "core.notesref")) {
 497                 notes_ref_name = xstrdup(value);
 498                 return 0;
 499         }
 500
 501         if (!strcmp(var, "core.pager"))
 502                 return git_config_string(&pager_program, var, value);
 503
 504         if (!strcmp(var, "core.editor"))
 505                 return git_config_string(&editor_program, var, value);
 506
 507         if (!strcmp(var, "core.excludesfile"))
 508                 return git_config_pathname(&excludes_file, var, value);
 509
 510         if (!strcmp(var, "core.whitespace")) {
 511                 if (!value)
 512                         return config_error_nonbool(var);
 513                 whitespace_rule_cfg = parse_whitespace_rule(value);
 514                 return 0;
 515         }
 516
 517         if (!strcmp(var, "core.fsyncobjectfiles")) {
 518                 fsync_object_files = git_config_bool(var, value);
 519                 return 0;
 520         }
 521
 522         if (!strcmp(var, "core.preloadindex")) {
 523                 core_preload_index = git_config_bool(var, value);
 524                 return 0;
 525         }
 526
 527         if (!strcmp(var, "core.createobject")) {
 528                 if (!strcmp(value, "rename"))
 529                         object_creation_mode = OBJECT_CREATION_USES_RENAMES;
 530                 else if (!strcmp(value, "link"))
 531                         object_creation_mode = OBJECT_CREATION_USES_HARDLINKS;
 532                 else
 533                         die("Invalid mode for object creation: %s", value);
 534                 return 0;
 535         }
 536
 537         if (!strcmp(var, "core.sparsecheckout")) {
 538                 core_apply_sparse_checkout = git_config_bool(var, value);
 539                 return 0;
 540         }
 541
 542         /* Add other config variables here and to Documentation/config.txt. */
 543         return 0;
 544 }
 545
 546 static int git_default_user_config(const char *var, const char *value)
 547 {
 548         if (!strcmp(var, "user.name")) {
 549                 if (!value)
 550                         return config_error_nonbool(var);
 551                 strlcpy(git_default_name, value, sizeof(git_default_name));
 552                 user_ident_explicitly_given |= IDENT_NAME_GIVEN;
 553                 return 0;
 554         }
 555
 556         if (!strcmp(var, "user.email")) {
 557                 if (!value)
 558                         return config_error_nonbool(var);
 559                 strlcpy(git_default_email, value, sizeof(git_default_email));
 560                 user_ident_explicitly_given |= IDENT_MAIL_GIVEN;
 561                 return 0;
 562         }
 563
 564         /* Add other config variables here and to Documentation/config.txt. */
 565         return 0;
 566 }
 567
 568 static int git_default_i18n_config(const char *var, const char *value)
 569 {
 570         if (!strcmp(var, "i18n.commitencoding"))
 571                 return git_config_string(&git_commit_encoding, var, value);
 572
 573         if (!strcmp(var, "i18n.logoutputencoding"))
 574                 return git_config_string(&git_log_output_encoding, var, value);
 575
 576         /* Add other config variables here and to Documentation/config.txt. */
 577         return 0;
 578 }
 579
 580 static int git_default_branch_config(const char *var, const char *value)
 581 {
 582         if (!strcmp(var, "branch.autosetupmerge")) {
 583                 if (value && !strcasecmp(value, "always")) {
 584                         git_branch_track = BRANCH_TRACK_ALWAYS;
 585                         return 0;
 586                 }
 587                 git_branch_track = git_config_bool(var, value);
 588                 return 0;
 589         }
 590         if (!strcmp(var, "branch.autosetuprebase")) {
 591                 if (!value)
 592                         return config_error_nonbool(var);
 593                 else if (!strcmp(value, "never"))
 594                         autorebase = AUTOREBASE_NEVER;
 595                 else if (!strcmp(value, "local"))
 596                         autorebase = AUTOREBASE_LOCAL;
 597                 else if (!strcmp(value, "remote"))
 598                         autorebase = AUTOREBASE_REMOTE;
 599                 else if (!strcmp(value, "always"))
 600                         autorebase = AUTOREBASE_ALWAYS;
 601                 else
 602                         return error("Malformed value for %s", var);
 603                 return 0;
 604         }
 605
 606         /* Add other config variables here and to Documentation/config.txt. */
 607         return 0;
 608 }
 609
 610 static int git_default_push_config(const char *var, const char *value)
 611 {
 612         if (!strcmp(var, "push.default")) {
 613                 if (!value)
 614                         return config_error_nonbool(var);
 615                 else if (!strcmp(value, "nothing"))
 616                         push_default = PUSH_DEFAULT_NOTHING;
 617                 else if (!strcmp(value, "matching"))
 618                         push_default = PUSH_DEFAULT_MATCHING;
 619                 else if (!strcmp(value, "tracking"))
 620                         push_default = PUSH_DEFAULT_TRACKING;
 621                 else if (!strcmp(value, "current"))
 622                         push_default = PUSH_DEFAULT_CURRENT;
 623                 else {
 624                         error("Malformed value for %s: %s", var, value);
 625                         return error("Must be one of nothing, matching, "
 626                                      "tracking or current.");
 627                 }
 628                 return 0;
 629         }
 630
 631         /* Add other config variables here and to Documentation/config.txt. */
 632         return 0;
 633 }
 634
 635 static int git_default_mailmap_config(const char *var, const char *value)
 636 {
 637         if (!strcmp(var, "mailmap.file"))
 638                 return git_config_string(&git_mailmap_file, var, value);
 639
 640         /* Add other config variables here and to Documentation/config.txt. */
 641         return 0;
 642 }
 643
 644 int git_default_config(const char *var, const char *value, void *dummy)
 645 {
 646         if (!prefixcmp(var, "core."))
 647                 return git_default_core_config(var, value);
 648
 649         if (!prefixcmp(var, "user."))
 650                 return git_default_user_config(var, value);
 651
 652         if (!prefixcmp(var, "i18n."))
 653                 return git_default_i18n_config(var, value);
 654
 655         if (!prefixcmp(var, "branch."))
 656                 return git_default_branch_config(var, value);
 657
 658         if (!prefixcmp(var, "push."))
 659                 return git_default_push_config(var, value);
 660
 661         if (!prefixcmp(var, "mailmap."))
 662                 return git_default_mailmap_config(var, value);
 663
 664         if (!prefixcmp(var, "advice."))
 665                 return git_default_advice_config(var, value);
 666
 667         if (!strcmp(var, "pager.color") || !strcmp(var, "color.pager")) {
 668                 pager_use_color = git_config_bool(var,value);
 669                 return 0;
 670         }
 671
 672         /* Add other config variables here and to Documentation/config.txt. */
 673         return 0;
 674 }
 675
 676 int git_config_from_file(config_fn_t fn, const char *filename, void *data)
 677 {
 678         int ret;
 679         FILE *f = fopen(filename, "r");
 680
 681         ret = -1;
 682         if (f) {
 683                 config_file = f;
 684                 config_file_name = filename;
 685                 config_linenr = 1;
 686                 config_file_eof = 0;
 687                 ret = git_parse_file(fn, data);
 688                 fclose(f);
 689                 config_file_name = NULL;
 690         }
 691         return ret;
 692 }
 693
 694 const char *git_etc_gitconfig(void)
 695 {
 696         static const char *system_wide;
 697         if (!system_wide)
 698                 system_wide = system_path(ETC_GITCONFIG);
 699         return system_wide;
 700 }
 701
 702 static int git_env_bool(const char *k, int def)
 703 {
 704         const char *v = getenv(k);
 705         return v ? git_config_bool(k, v) : def;
 706 }
 707
 708 int git_config_system(void)
 709 {
 710         return !git_env_bool("GIT_CONFIG_NOSYSTEM", 0);
 711 }
 712
 713 int git_config_global(void)
 714 {
 715         return !git_env_bool("GIT_CONFIG_NOGLOBAL", 0);
 716 }
 717
 718 int git_config(config_fn_t fn, void *data)
 719 {
 720         int ret = 0, found = 0;
 721         char *repo_config = NULL;
 722         const char *home = NULL;
 723
 724         /* Setting $GIT_CONFIG makes git read _only_ the given config file. */
 725         if (config_exclusive_filename)
 726                 return git_config_from_file(fn, config_exclusive_filename, data);
 727         if (git_config_system() && !access(git_etc_gitconfig(), R_OK)) {
 728                 ret += git_config_from_file(fn, git_etc_gitconfig(),
 729                                             data);
 730                 found += 1;
 731         }
 732
 733         home = getenv("HOME");
 734         if (git_config_global() && home) {
 735                 char *user_config = xstrdup(mkpath("%s/.gitconfig", home));
 736                 if (!access(user_config, R_OK)) {
 737                         ret += git_config_from_file(fn, user_config, data);
 738                         found += 1;
 739                 }
 740                 free(user_config);
 741         }
 742
 743         repo_config = git_pathdup("config");
 744         if (!access(repo_config, R_OK)) {
 745                 ret += git_config_from_file(fn, repo_config, data);
 746                 found += 1;
 747         }
 748         free(repo_config);
 749         if (found == 0)
 750                 return -1;
 751         return ret;
 752 }
 753
 754 /*
 755  * Find all the stuff for git_config_set() below.
 756  */
 757
 758 #define MAX_MATCHES 512
 759
 760 static struct {
 761         int baselen;
 762         char *key;
 763         int do_not_match;
 764         regex_t *value_regex;
 765         int multi_replace;
 766         size_t offset[MAX_MATCHES];
 767         enum { START, SECTION_SEEN, SECTION_END_SEEN, KEY_SEEN } state;
 768         int seen;
 769 } store;
 770
 771 static int matches(const char *key, const char *value)
 772 {
 773         return !strcmp(key, store.key) &&
 774                 (store.value_regex == NULL ||
 775                  (store.do_not_match ^
 776                   !regexec(store.value_regex, value, 0, NULL, 0)));
 777 }
 778
 779 static int store_aux(const char *key, const char *value, void *cb)
 780 {
 781         const char *ep;
 782         size_t section_len;
 783
 784         switch (store.state) {
 785         case KEY_SEEN:
 786                 if (matches(key, value)) {
 787                         if (store.seen == 1 && store.multi_replace == 0) {
 788                                 warning("%s has multiple values", key);
 789                         } else if (store.seen >= MAX_MATCHES) {
 790                                 error("too many matches for %s", key);
 791                                 return 1;
 792                         }
 793
 794                         store.offset[store.seen] = ftell(config_file);
 795                         store.seen++;
 796                 }
 797                 break;
 798         case SECTION_SEEN:
 799                 /*
 800                  * What we are looking for is in store.key (both
 801                  * section and var), and its section part is baselen
 802                  * long.  We found key (again, both section and var).
 803                  * We would want to know if this key is in the same
 804                  * section as what we are looking for.  We already
 805                  * know we are in the same section as what should
 806                  * hold store.key.
 807                  */
 808                 ep = strrchr(key, '.');
 809                 section_len = ep - key;
 810
 811                 if ((section_len != store.baselen) ||
 812                     memcmp(key, store.key, section_len+1)) {
 813                         store.state = SECTION_END_SEEN;
 814                         break;
 815                 }
 816
 817                 /*
 818                  * Do not increment matches: this is no match, but we
 819                  * just made sure we are in the desired section.
 820                  */
 821                 store.offset[store.seen] = ftell(config_file);
 822                 /* fallthru */
 823         case SECTION_END_SEEN:
 824         case START:
 825                 if (matches(key, value)) {
 826                         store.offset[store.seen] = ftell(config_file);
 827                         store.state = KEY_SEEN;
 828                         store.seen++;
 829                 } else {
 830                         if (strrchr(key, '.') - key == store.baselen &&
 831                               !strncmp(key, store.key, store.baselen)) {
 832                                         store.state = SECTION_SEEN;
 833                                         store.offset[store.seen] = ftell(config_file);
 834                         }
 835                 }
 836         }
 837         return 0;
 838 }
 839
 840 static int write_error(const char *filename)
 841 {
 842         error("failed to write new configuration file %s", filename);
 843
 844         /* Same error code as "failed to rename". */
 845         return 4;
 846 }
 847
 848 static int store_write_section(int fd, const char *key)
 849 {
 850         const char *dot;
 851         int i, success;
 852         struct strbuf sb = STRBUF_INIT;
 853
 854         dot = memchr(key, '.', store.baselen);
 855         if (dot) {
 856                 strbuf_addf(&sb, "[%.*s \"", (int)(dot - key), key);
 857                 for (i = dot - key + 1; i < store.baselen; i++) {
 858                         if (key[i] == '"' || key[i] == '\\')
 859                                 strbuf_addch(&sb, '\\');
 860                         strbuf_addch(&sb, key[i]);
 861                 }
 862                 strbuf_addstr(&sb, "\"]\n");
 863         } else {
 864                 strbuf_addf(&sb, "[%.*s]\n", store.baselen, key);
 865         }
 866
 867         success = write_in_full(fd, sb.buf, sb.len) == sb.len;
 868         strbuf_release(&sb);
 869
 870         return success;
 871 }
 872
 873 static int store_write_pair(int fd, const char *key, const char *value)
 874 {
 875         int i, success;
 876         int length = strlen(key + store.baselen + 1);
 877         const char *quote = "";
 878         struct strbuf sb = STRBUF_INIT;
 879
 880         /*
 881          * Check to see if the value needs to be surrounded with a dq pair.
 882          * Note that problematic characters are always backslash-quoted; this
 883          * check is about not losing leading or trailing SP and strings that
 884          * follow beginning-of-comment characters (i.e. ';' and '#') by the
 885          * configuration parser.
 886          */
 887         if (value[0] == ' ')
 888                 quote = "\"";
 889         for (i = 0; value[i]; i++)
 890                 if (value[i] == ';' || value[i] == '#')
 891                         quote = "\"";
 892         if (i && value[i - 1] == ' ')
 893                 quote = "\"";
 894
 895         strbuf_addf(&sb, "\t%.*s = %s",
 896                     length, key + store.baselen + 1, quote);
 897
 898         for (i = 0; value[i]; i++)
 899                 switch (value[i]) {
 900                 case '\n':
 901                         strbuf_addstr(&sb, "\\n");
 902                         break;
 903                 case '\t':
 904                         strbuf_addstr(&sb, "\\t");
 905                         break;
 906                 case '"':
 907                 case '\\':
 908                         strbuf_addch(&sb, '\\');
 909                 default:
 910                         strbuf_addch(&sb, value[i]);
 911                         break;
 912                 }
 913         strbuf_addf(&sb, "%s\n", quote);
 914
 915         success = write_in_full(fd, sb.buf, sb.len) == sb.len;
 916         strbuf_release(&sb);
 917
 918         return success;
 919 }
 920
 921 static ssize_t find_beginning_of_line(const char *contents, size_t size,
 922         size_t offset_, int *found_bracket)
 923 {
 924         size_t equal_offset = size, bracket_offset = size;
 925         ssize_t offset;
 926
 927 contline:
 928         for (offset = offset_-2; offset > 0
 929                         && contents[offset] != '\n'; offset--)
 930                 switch (contents[offset]) {
 931                         case '=': equal_offset = offset; break;
 932                         case ']': bracket_offset = offset; break;
 933                 }
 934         if (offset > 0 && contents[offset-1] == '\\') {
 935                 offset_ = offset;
 936                 goto contline;
 937         }
 938         if (bracket_offset < equal_offset) {
 939                 *found_bracket = 1;
 940                 offset = bracket_offset+1;
 941         } else
 942                 offset++;
 943
 944         return offset;
 945 }
 946
 947 int git_config_set(const char *key, const char *value)
 948 {
 949         return git_config_set_multivar(key, value, NULL, 0);
 950 }
 951
 952 /*
 953  * If value==NULL, unset in (remove from) config,
 954  * if value_regex!=NULL, disregard key/value pairs where value does not match.
 955  * if multi_replace==0, nothing, or only one matching key/value is replaced,
 956  *     else all matching key/values (regardless how many) are removed,
 957  *     before the new pair is written.
 958  *
 959  * Returns 0 on success.
 960  *
 961  * This function does this:
 962  *
 963  * - it locks the config file by creating ".git/config.lock"
 964  *
 965  * - it then parses the config using store_aux() as validator to find
 966  *   the position on the key/value pair to replace. If it is to be unset,
 967  *   it must be found exactly once.
 968  *
 969  * - the config file is mmap()ed and the part before the match (if any) is
 970  *   written to the lock file, then the changed part and the rest.
 971  *
 972  * - the config file is removed and the lock file rename()d to it.
 973  *
 974  */
 975 int git_config_set_multivar(const char *key, const char *value,
 976         const char *value_regex, int multi_replace)
 977 {
 978         int i, dot;
 979         int fd = -1, in_fd;
 980         int ret;
 981         char *config_filename;
 982         struct lock_file *lock = NULL;
 983         const char *last_dot = strrchr(key, '.');
 984
 985         if (config_exclusive_filename)
 986                 config_filename = xstrdup(config_exclusive_filename);
 987         else
 988                 config_filename = git_pathdup("config");
 989
 990         /*
 991          * Since "key" actually contains the section name and the real
 992          * key name separated by a dot, we have to know where the dot is.
 993          */
 994
 995         if (last_dot == NULL) {
 996                 error("key does not contain a section: %s", key);
 997                 ret = 2;
 998                 goto out_free;
 999         }
1000         store.baselen = last_dot - key;
1001
1002         store.multi_replace = multi_replace;
1003
1004         /*
1005          * Validate the key and while at it, lower case it for matching.
1006          */
1007         store.key = xmalloc(strlen(key) + 1);
1008         dot = 0;
1009         for (i = 0; key[i]; i++) {
1010                 unsigned char c = key[i];
1011                 if (c == '.')
1012                         dot = 1;
1013                 /* Leave the extended basename untouched.. */
1014                 if (!dot || i > store.baselen) {
1015                         if (!iskeychar(c) || (i == store.baselen+1 && !isalpha(c))) {
1016                                 error("invalid key: %s", key);
1017                                 free(store.key);
1018                                 ret = 1;
1019                                 goto out_free;
1020                         }
1021                         c = tolower(c);
1022                 } else if (c == '\n') {
1023                         error("invalid key (newline): %s", key);
1024                         free(store.key);
1025                         ret = 1;
1026                         goto out_free;
1027                 }
1028                 store.key[i] = c;
1029         }
1030         store.key[i] = 0;
1031
1032         /*
1033          * The lock serves a purpose in addition to locking: the new
1034          * contents of .git/config will be written into it.
1035          */
1036         lock = xcalloc(sizeof(struct lock_file), 1);
1037         fd = hold_lock_file_for_update(lock, config_filename, 0);
1038         if (fd < 0) {
1039                 error("could not lock config file %s: %s", config_filename, strerror(errno));
1040                 free(store.key);
1041                 ret = -1;
1042                 goto out_free;
1043         }
1044
1045         /*
1046          * If .git/config does not exist yet, write a minimal version.
1047          */
1048         in_fd = open(config_filename, O_RDONLY);
1049         if ( in_fd < 0 ) {
1050                 free(store.key);
1051
1052                 if ( ENOENT != errno ) {
1053                         error("opening %s: %s", config_filename,
1054                               strerror(errno));
1055                         ret = 3; /* same as "invalid config file" */
1056                         goto out_free;
1057                 }
1058                 /* if nothing to unset, error out */
1059                 if (value == NULL) {
1060                         ret = 5;
1061                         goto out_free;
1062                 }
1063
1064                 store.key = (char *)key;
1065                 if (!store_write_section(fd, key) ||
1066                     !store_write_pair(fd, key, value))
1067                         goto write_err_out;
1068         } else {
1069                 struct stat st;
1070                 char *contents;
1071                 size_t contents_sz, copy_begin, copy_end;
1072                 int i, new_line = 0;
1073
1074                 if (value_regex == NULL)
1075                         store.value_regex = NULL;
1076                 else {
1077                         if (value_regex[0] == '!') {
1078                                 store.do_not_match = 1;
1079                                 value_regex++;
1080                         } else
1081                                 store.do_not_match = 0;
1082
1083                         store.value_regex = (regex_t*)xmalloc(sizeof(regex_t));
1084                         if (regcomp(store.value_regex, value_regex,
1085                                         REG_EXTENDED)) {
1086                                 error("invalid pattern: %s", value_regex);
1087                                 free(store.value_regex);
1088                                 ret = 6;
1089                                 goto out_free;
1090                         }
1091                 }
1092
1093                 store.offset[0] = 0;
1094                 store.state = START;
1095                 store.seen = 0;
1096
1097                 /*
1098                  * After this, store.offset will contain the *end* offset
1099                  * of the last match, or remain at 0 if no match was found.
1100                  * As a side effect, we make sure to transform only a valid
1101                  * existing config file.
1102                  */
1103                 if (git_config_from_file(store_aux, config_filename, NULL)) {
1104                         error("invalid config file %s", config_filename);
1105                         free(store.key);
1106                         if (store.value_regex != NULL) {
1107                                 regfree(store.value_regex);
1108                                 free(store.value_regex);
1109                         }
1110                         ret = 3;
1111                         goto out_free;
1112                 }
1113
1114                 free(store.key);
1115                 if (store.value_regex != NULL) {
1116                         regfree(store.value_regex);
1117                         free(store.value_regex);
1118                 }
1119
1120                 /* if nothing to unset, or too many matches, error out */
1121                 if ((store.seen == 0 && value == NULL) ||
1122                                 (store.seen > 1 && multi_replace == 0)) {
1123                         ret = 5;
1124                         goto out_free;
1125                 }
1126
1127                 fstat(in_fd, &st);
1128                 contents_sz = xsize_t(st.st_size);
1129                 contents = xmmap(NULL, contents_sz, PROT_READ,
1130                         MAP_PRIVATE, in_fd, 0);
1131                 close(in_fd);
1132
1133                 if (store.seen == 0)
1134                         store.seen = 1;
1135
1136                 for (i = 0, copy_begin = 0; i < store.seen; i++) {
1137                         if (store.offset[i] == 0) {
1138                                 store.offset[i] = copy_end = contents_sz;
1139                         } else if (store.state != KEY_SEEN) {
1140                                 copy_end = store.offset[i];
1141                         } else
1142                                 copy_end = find_beginning_of_line(
1143                                         contents, contents_sz,
1144                                         store.offset[i]-2, &new_line);
1145
1146                         if (copy_end > 0 && contents[copy_end-1] != '\n')
1147                                 new_line = 1;
1148
1149                         /* write the first part of the config */
1150                         if (copy_end > copy_begin) {
1151                                 if (write_in_full(fd, contents + copy_begin,
1152                                                   copy_end - copy_begin) <
1153                                     copy_end - copy_begin)
1154                                         goto write_err_out;
1155                                 if (new_line &&
1156                                     write_str_in_full(fd, "\n") != 1)
1157                                         goto write_err_out;
1158                         }
1159                         copy_begin = store.offset[i];
1160                 }
1161
1162                 /* write the pair (value == NULL means unset) */
1163                 if (value != NULL) {
1164                         if (store.state == START) {
1165                                 if (!store_write_section(fd, key))
1166                                         goto write_err_out;
1167                         }
1168                         if (!store_write_pair(fd, key, value))
1169                                 goto write_err_out;
1170                 }
1171
1172                 /* write the rest of the config */
1173                 if (copy_begin < contents_sz)
1174                         if (write_in_full(fd, contents + copy_begin,
1175                                           contents_sz - copy_begin) <
1176                             contents_sz - copy_begin)
1177                                 goto write_err_out;
1178
1179                 munmap(contents, contents_sz);
1180         }
1181
1182         if (commit_lock_file(lock) < 0) {
1183                 error("could not commit config file %s", config_filename);
1184                 ret = 4;
1185                 goto out_free;
1186         }
1187
1188         /*
1189          * lock is committed, so don't try to roll it back below.
1190          * NOTE: Since lockfile.c keeps a linked list of all created
1191          * lock_file structures, it isn't safe to free(lock).  It's
1192          * better to just leave it hanging around.
1193          */
1194         lock = NULL;
1195         ret = 0;
1196
1197 out_free:
1198         if (lock)
1199                 rollback_lock_file(lock);
1200         free(config_filename);
1201         return ret;
1202
1203 write_err_out:
1204         ret = write_error(lock->filename);
1205         goto out_free;
1206
1207 }
1208
1209 static int section_name_match (const char *buf, const char *name)
1210 {
1211         int i = 0, j = 0, dot = 0;
1212         if (buf[i] != '[')
1213                 return 0;
1214         for (i = 1; buf[i] && buf[i] != ']'; i++) {
1215                 if (!dot && isspace(buf[i])) {
1216                         dot = 1;
1217                         if (name[j++] != '.')
1218                                 break;
1219                         for (i++; isspace(buf[i]); i++)
1220                                 ; /* do nothing */
1221                         if (buf[i] != '"')
1222                                 break;
1223                         continue;
1224                 }
1225                 if (buf[i] == '\\' && dot)
1226                         i++;
1227                 else if (buf[i] == '"' && dot) {
1228                         for (i++; isspace(buf[i]); i++)
1229                                 ; /* do_nothing */
1230                         break;
1231                 }
1232                 if (buf[i] != name[j++])
1233                         break;
1234         }
1235         if (buf[i] == ']' && name[j] == 0) {
1236                 /*
1237                  * We match, now just find the right length offset by
1238                  * gobbling up any whitespace after it, as well
1239                  */
1240                 i++;
1241                 for (; buf[i] && isspace(buf[i]); i++)
1242                         ; /* do nothing */
1243                 return i;
1244         }
1245         return 0;
1246 }
1247
1248 /* if new_name == NULL, the section is removed instead */
1249 int git_config_rename_section(const char *old_name, const char *new_name)
1250 {
1251         int ret = 0, remove = 0;
1252         char *config_filename;
1253         struct lock_file *lock = xcalloc(sizeof(struct lock_file), 1);
1254         int out_fd;
1255         char buf[1024];
1256
1257         if (config_exclusive_filename)
1258                 config_filename = xstrdup(config_exclusive_filename);
1259         else
1260                 config_filename = git_pathdup("config");
1261         out_fd = hold_lock_file_for_update(lock, config_filename, 0);
1262         if (out_fd < 0) {
1263                 ret = error("could not lock config file %s", config_filename);
1264                 goto out;
1265         }
1266
1267         if (!(config_file = fopen(config_filename, "rb"))) {
1268                 /* no config file means nothing to rename, no error */
1269                 goto unlock_and_out;
1270         }
1271
1272         while (fgets(buf, sizeof(buf), config_file)) {
1273                 int i;
1274                 int length;
1275                 char *output = buf;
1276                 for (i = 0; buf[i] && isspace(buf[i]); i++)
1277                         ; /* do nothing */
1278                 if (buf[i] == '[') {
1279                         /* it's a section */
1280                         int offset = section_name_match(&buf[i], old_name);
1281                         if (offset > 0) {
1282                                 ret++;
1283                                 if (new_name == NULL) {
1284                                         remove = 1;
1285                                         continue;
1286                                 }
1287                                 store.baselen = strlen(new_name);
1288                                 if (!store_write_section(out_fd, new_name)) {
1289                                         ret = write_error(lock->filename);
1290                                         goto out;
1291                                 }
1292                                 /*
1293                                  * We wrote out the new section, with
1294                                  * a newline, now skip the old
1295                                  * section's length
1296                                  */
1297                                 output += offset + i;
1298                                 if (strlen(output) > 0) {
1299                                         /*
1300                                          * More content means there's
1301                                          * a declaration to put on the
1302                                          * next line; indent with a
1303                                          * tab
1304                                          */
1305                                         output -= 1;
1306                                         output[0] = '\t';
1307                                 }
1308                         }
1309                         remove = 0;
1310                 }
1311                 if (remove)
1312                         continue;
1313                 length = strlen(output);
1314                 if (write_in_full(out_fd, output, length) != length) {
1315                         ret = write_error(lock->filename);
1316                         goto out;
1317                 }
1318         }
1319         fclose(config_file);
1320  unlock_and_out:
1321         if (commit_lock_file(lock) < 0)
1322                 ret = error("could not commit config file %s", config_filename);
1323  out:
1324         free(config_filename);
1325         return ret;
1326 }
1327
1328 /*
1329  * Call this to report error for your variable that should not
1330  * get a boolean value (i.e. "[my] var" means "true").
1331  */
1332 int config_error_nonbool(const char *var)
1333 {
1334         return error("Missing value for '%s'", var);
1335 }