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 #include "strbuf.h"
  11 #include "quote.h"
  12
  13 struct config_source {
  14         struct config_source *prev;
  15         union {
  16                 FILE *file;
  17                 struct config_buf {
  18                         const char *buf;
  19                         size_t len;
  20                         size_t pos;
  21                 } buf;
  22         } u;
  23         const char *name;
  24         int die_on_error;
  25         int linenr;
  26         int eof;
  27         struct strbuf value;
  28         struct strbuf var;
  29
  30         int (*fgetc)(struct config_source *c);
  31         int (*ungetc)(int c, struct config_source *conf);
  32         long (*ftell)(struct config_source *c);
  33 };
  34
  35 static struct config_source *cf;
  36
  37 static int zlib_compression_seen;
  38
  39 static int config_file_fgetc(struct config_source *conf)
  40 {
  41         return fgetc(conf->u.file);
  42 }
  43
  44 static int config_file_ungetc(int c, struct config_source *conf)
  45 {
  46         return ungetc(c, conf->u.file);
  47 }
  48
  49 static long config_file_ftell(struct config_source *conf)
  50 {
  51         return ftell(conf->u.file);
  52 }
  53
  54
  55 static int config_buf_fgetc(struct config_source *conf)
  56 {
  57         if (conf->u.buf.pos < conf->u.buf.len)
  58                 return conf->u.buf.buf[conf->u.buf.pos++];
  59
  60         return EOF;
  61 }
  62
  63 static int config_buf_ungetc(int c, struct config_source *conf)
  64 {
  65         if (conf->u.buf.pos > 0)
  66                 return conf->u.buf.buf[--conf->u.buf.pos];
  67
  68         return EOF;
  69 }
  70
  71 static long config_buf_ftell(struct config_source *conf)
  72 {
  73         return conf->u.buf.pos;
  74 }
  75
  76 #define MAX_INCLUDE_DEPTH 10
  77 static const char include_depth_advice[] =
  78 "exceeded maximum include depth (%d) while including\n"
  79 "       %s\n"
  80 "from\n"
  81 "       %s\n"
  82 "Do you have circular includes?";
  83 static int handle_path_include(const char *path, struct config_include_data *inc)
  84 {
  85         int ret = 0;
  86         struct strbuf buf = STRBUF_INIT;
  87         char *expanded = expand_user_path(path);
  88
  89         if (!expanded)
  90                 return error("Could not expand include path '%s'", path);
  91         path = expanded;
  92
  93         /*
  94          * Use an absolute path as-is, but interpret relative paths
  95          * based on the including config file.
  96          */
  97         if (!is_absolute_path(path)) {
  98                 char *slash;
  99
 100                 if (!cf || !cf->name)
 101                         return error("relative config includes must come from files");
 102
 103                 slash = find_last_dir_sep(cf->name);
 104                 if (slash)
 105                         strbuf_add(&buf, cf->name, slash - cf->name + 1);
 106                 strbuf_addstr(&buf, path);
 107                 path = buf.buf;
 108         }
 109
 110         if (!access_or_die(path, R_OK, 0)) {
 111                 if (++inc->depth > MAX_INCLUDE_DEPTH)
 112                         die(include_depth_advice, MAX_INCLUDE_DEPTH, path,
 113                             cf && cf->name ? cf->name : "the command line");
 114                 ret = git_config_from_file(git_config_include, path, inc);
 115                 inc->depth--;
 116         }
 117         strbuf_release(&buf);
 118         free(expanded);
 119         return ret;
 120 }
 121
 122 int git_config_include(const char *var, const char *value, void *data)
 123 {
 124         struct config_include_data *inc = data;
 125         const char *type;
 126         int ret;
 127
 128         /*
 129          * Pass along all values, including "include" directives; this makes it
 130          * possible to query information on the includes themselves.
 131          */
 132         ret = inc->fn(var, value, inc->data);
 133         if (ret < 0)
 134                 return ret;
 135
 136         type = skip_prefix(var, "include.");
 137         if (!type)
 138                 return ret;
 139
 140         if (!strcmp(type, "path"))
 141                 ret = handle_path_include(value, inc);
 142         return ret;
 143 }
 144
 145 static void lowercase(char *p)
 146 {
 147         for (; *p; p++)
 148                 *p = tolower(*p);
 149 }
 150
 151 void git_config_push_parameter(const char *text)
 152 {
 153         struct strbuf env = STRBUF_INIT;
 154         const char *old = getenv(CONFIG_DATA_ENVIRONMENT);
 155         if (old) {
 156                 strbuf_addstr(&env, old);
 157                 strbuf_addch(&env, ' ');
 158         }
 159         sq_quote_buf(&env, text);
 160         setenv(CONFIG_DATA_ENVIRONMENT, env.buf, 1);
 161         strbuf_release(&env);
 162 }
 163
 164 int git_config_parse_parameter(const char *text,
 165                                config_fn_t fn, void *data)
 166 {
 167         struct strbuf **pair;
 168         pair = strbuf_split_str(text, '=', 2);
 169         if (!pair[0])
 170                 return error("bogus config parameter: %s", text);
 171         if (pair[0]->len && pair[0]->buf[pair[0]->len - 1] == '=')
 172                 strbuf_setlen(pair[0], pair[0]->len - 1);
 173         strbuf_trim(pair[0]);
 174         if (!pair[0]->len) {
 175                 strbuf_list_free(pair);
 176                 return error("bogus config parameter: %s", text);
 177         }
 178         lowercase(pair[0]->buf);
 179         if (fn(pair[0]->buf, pair[1] ? pair[1]->buf : NULL, data) < 0) {
 180                 strbuf_list_free(pair);
 181                 return -1;
 182         }
 183         strbuf_list_free(pair);
 184         return 0;
 185 }
 186
 187 int git_config_from_parameters(config_fn_t fn, void *data)
 188 {
 189         const char *env = getenv(CONFIG_DATA_ENVIRONMENT);
 190         char *envw;
 191         const char **argv = NULL;
 192         int nr = 0, alloc = 0;
 193         int i;
 194
 195         if (!env)
 196                 return 0;
 197         /* sq_dequote will write over it */
 198         envw = xstrdup(env);
 199
 200         if (sq_dequote_to_argv(envw, &argv, &nr, &alloc) < 0) {
 201                 free(envw);
 202                 return error("bogus format in " CONFIG_DATA_ENVIRONMENT);
 203         }
 204
 205         for (i = 0; i < nr; i++) {
 206                 if (git_config_parse_parameter(argv[i], fn, data) < 0) {
 207                         free(argv);
 208                         free(envw);
 209                         return -1;
 210                 }
 211         }
 212
 213         free(argv);
 214         free(envw);
 215         return nr > 0;
 216 }
 217
 218 static int get_next_char(void)
 219 {
 220         int c = cf->fgetc(cf);
 221
 222         if (c == '\r') {
 223                 /* DOS like systems */
 224                 c = cf->fgetc(cf);
 225                 if (c != '\n') {
 226                         cf->ungetc(c, cf);
 227                         c = '\r';
 228                 }
 229         }
 230         if (c == '\n')
 231                 cf->linenr++;
 232         if (c == EOF) {
 233                 cf->eof = 1;
 234                 c = '\n';
 235         }
 236         return c;
 237 }
 238
 239 static char *parse_value(void)
 240 {
 241         int quote = 0, comment = 0, space = 0;
 242
 243         strbuf_reset(&cf->value);
 244         for (;;) {
 245                 int c = get_next_char();
 246                 if (c == '\n') {
 247                         if (quote) {
 248                                 cf->linenr--;
 249                                 return NULL;
 250                         }
 251                         return cf->value.buf;
 252                 }
 253                 if (comment)
 254                         continue;
 255                 if (isspace(c) && !quote) {
 256                         if (cf->value.len)
 257                                 space++;
 258                         continue;
 259                 }
 260                 if (!quote) {
 261                         if (c == ';' || c == '#') {
 262                                 comment = 1;
 263                                 continue;
 264                         }
 265                 }
 266                 for (; space; space--)
 267                         strbuf_addch(&cf->value, ' ');
 268                 if (c == '\\') {
 269                         c = get_next_char();
 270                         switch (c) {
 271                         case '\n':
 272                                 continue;
 273                         case 't':
 274                                 c = '\t';
 275                                 break;
 276                         case 'b':
 277                                 c = '\b';
 278                                 break;
 279                         case 'n':
 280                                 c = '\n';
 281                                 break;
 282                         /* Some characters escape as themselves */
 283                         case '\\': case '"':
 284                                 break;
 285                         /* Reject unknown escape sequences */
 286                         default:
 287                                 return NULL;
 288                         }
 289                         strbuf_addch(&cf->value, c);
 290                         continue;
 291                 }
 292                 if (c == '"') {
 293                         quote = 1-quote;
 294                         continue;
 295                 }
 296                 strbuf_addch(&cf->value, c);
 297         }
 298 }
 299
 300 static inline int iskeychar(int c)
 301 {
 302         return isalnum(c) || c == '-';
 303 }
 304
 305 static int get_value(config_fn_t fn, void *data, struct strbuf *name)
 306 {
 307         int c;
 308         char *value;
 309
 310         /* Get the full name */
 311         for (;;) {
 312                 c = get_next_char();
 313                 if (cf->eof)
 314                         break;
 315                 if (!iskeychar(c))
 316                         break;
 317                 strbuf_addch(name, tolower(c));
 318         }
 319
 320         while (c == ' ' || c == '\t')
 321                 c = get_next_char();
 322
 323         value = NULL;
 324         if (c != '\n') {
 325                 if (c != '=')
 326                         return -1;
 327                 value = parse_value();
 328                 if (!value)
 329                         return -1;
 330         }
 331         return fn(name->buf, value, data);
 332 }
 333
 334 static int get_extended_base_var(struct strbuf *name, int c)
 335 {
 336         do {
 337                 if (c == '\n')
 338                         goto error_incomplete_line;
 339                 c = get_next_char();
 340         } while (isspace(c));
 341
 342         /* We require the format to be '[base "extension"]' */
 343         if (c != '"')
 344                 return -1;
 345         strbuf_addch(name, '.');
 346
 347         for (;;) {
 348                 int c = get_next_char();
 349                 if (c == '\n')
 350                         goto error_incomplete_line;
 351                 if (c == '"')
 352                         break;
 353                 if (c == '\\') {
 354                         c = get_next_char();
 355                         if (c == '\n')
 356                                 goto error_incomplete_line;
 357                 }
 358                 strbuf_addch(name, c);
 359         }
 360
 361         /* Final ']' */
 362         if (get_next_char() != ']')
 363                 return -1;
 364         return 0;
 365 error_incomplete_line:
 366         cf->linenr--;
 367         return -1;
 368 }
 369
 370 static int get_base_var(struct strbuf *name)
 371 {
 372         for (;;) {
 373                 int c = get_next_char();
 374                 if (cf->eof)
 375                         return -1;
 376                 if (c == ']')
 377                         return 0;
 378                 if (isspace(c))
 379                         return get_extended_base_var(name, c);
 380                 if (!iskeychar(c) && c != '.')
 381                         return -1;
 382                 strbuf_addch(name, tolower(c));
 383         }
 384 }
 385
 386 static int git_parse_source(config_fn_t fn, void *data)
 387 {
 388         int comment = 0;
 389         int baselen = 0;
 390         struct strbuf *var = &cf->var;
 391
 392         /* U+FEFF Byte Order Mark in UTF8 */
 393         static const unsigned char *utf8_bom = (unsigned char *) "\xef\xbb\xbf";
 394         const unsigned char *bomptr = utf8_bom;
 395
 396         for (;;) {
 397                 int c = get_next_char();
 398                 if (bomptr && *bomptr) {
 399                         /* We are at the file beginning; skip UTF8-encoded BOM
 400                          * if present. Sane editors won't put this in on their
 401                          * own, but e.g. Windows Notepad will do it happily. */
 402                         if ((unsigned char) c == *bomptr) {
 403                                 bomptr++;
 404                                 continue;
 405                         } else {
 406                                 /* Do not tolerate partial BOM. */
 407                                 if (bomptr != utf8_bom)
 408                                         break;
 409                                 /* No BOM at file beginning. Cool. */
 410                                 bomptr = NULL;
 411                         }
 412                 }
 413                 if (c == '\n') {
 414                         if (cf->eof)
 415                                 return 0;
 416                         comment = 0;
 417                         continue;
 418                 }
 419                 if (comment || isspace(c))
 420                         continue;
 421                 if (c == '#' || c == ';') {
 422                         comment = 1;
 423                         continue;
 424                 }
 425                 if (c == '[') {
 426                         /* Reset prior to determining a new stem */
 427                         strbuf_reset(var);
 428                         if (get_base_var(var) < 0 || var->len < 1)
 429                                 break;
 430                         strbuf_addch(var, '.');
 431                         baselen = var->len;
 432                         continue;
 433                 }
 434                 if (!isalpha(c))
 435                         break;
 436                 /*
 437                  * Truncate the var name back to the section header
 438                  * stem prior to grabbing the suffix part of the name
 439                  * and the value.
 440                  */
 441                 strbuf_setlen(var, baselen);
 442                 strbuf_addch(var, tolower(c));
 443                 if (get_value(fn, data, var) < 0)
 444                         break;
 445         }
 446         if (cf->die_on_error)
 447                 die("bad config file line %d in %s", cf->linenr, cf->name);
 448         else
 449                 return error("bad config file line %d in %s", cf->linenr, cf->name);
 450 }
 451
 452 static int parse_unit_factor(const char *end, uintmax_t *val)
 453 {
 454         if (!*end)
 455                 return 1;
 456         else if (!strcasecmp(end, "k")) {
 457                 *val *= 1024;
 458                 return 1;
 459         }
 460         else if (!strcasecmp(end, "m")) {
 461                 *val *= 1024 * 1024;
 462                 return 1;
 463         }
 464         else if (!strcasecmp(end, "g")) {
 465                 *val *= 1024 * 1024 * 1024;
 466                 return 1;
 467         }
 468         return 0;
 469 }
 470
 471 static int git_parse_long(const char *value, long *ret)
 472 {
 473         if (value && *value) {
 474                 char *end;
 475                 intmax_t val;
 476                 uintmax_t uval;
 477                 uintmax_t factor = 1;
 478
 479                 errno = 0;
 480                 val = strtoimax(value, &end, 0);
 481                 if (errno == ERANGE)
 482                         return 0;
 483                 if (!parse_unit_factor(end, &factor))
 484                         return 0;
 485                 uval = abs(val);
 486                 uval *= factor;
 487                 if ((uval > maximum_signed_value_of_type(long)) ||
 488                     (abs(val) > uval))
 489                         return 0;
 490                 val *= factor;
 491                 *ret = val;
 492                 return 1;
 493         }
 494         return 0;
 495 }
 496
 497 int git_parse_ulong(const char *value, unsigned long *ret)
 498 {
 499         if (value && *value) {
 500                 char *end;
 501                 uintmax_t val;
 502                 uintmax_t oldval;
 503
 504                 errno = 0;
 505                 val = strtoumax(value, &end, 0);
 506                 if (errno == ERANGE)
 507                         return 0;
 508                 oldval = val;
 509                 if (!parse_unit_factor(end, &val))
 510                         return 0;
 511                 if ((val > maximum_unsigned_value_of_type(long)) ||
 512                     (oldval > val))
 513                         return 0;
 514                 *ret = val;
 515                 return 1;
 516         }
 517         return 0;
 518 }
 519
 520 static void die_bad_config(const char *name)
 521 {
 522         if (cf && cf->name)
 523                 die("bad config value for '%s' in %s", name, cf->name);
 524         die("bad config value for '%s'", name);
 525 }
 526
 527 int git_config_int(const char *name, const char *value)
 528 {
 529         long ret = 0;
 530         if (!git_parse_long(value, &ret))
 531                 die_bad_config(name);
 532         return ret;
 533 }
 534
 535 unsigned long git_config_ulong(const char *name, const char *value)
 536 {
 537         unsigned long ret;
 538         if (!git_parse_ulong(value, &ret))
 539                 die_bad_config(name);
 540         return ret;
 541 }
 542
 543 static int git_config_maybe_bool_text(const char *name, const char *value)
 544 {
 545         if (!value)
 546                 return 1;
 547         if (!*value)
 548                 return 0;
 549         if (!strcasecmp(value, "true")
 550             || !strcasecmp(value, "yes")
 551             || !strcasecmp(value, "on"))
 552                 return 1;
 553         if (!strcasecmp(value, "false")
 554             || !strcasecmp(value, "no")
 555             || !strcasecmp(value, "off"))
 556                 return 0;
 557         return -1;
 558 }
 559
 560 int git_config_maybe_bool(const char *name, const char *value)
 561 {
 562         long v = git_config_maybe_bool_text(name, value);
 563         if (0 <= v)
 564                 return v;
 565         if (git_parse_long(value, &v))
 566                 return !!v;
 567         return -1;
 568 }
 569
 570 int git_config_bool_or_int(const char *name, const char *value, int *is_bool)
 571 {
 572         int v = git_config_maybe_bool_text(name, value);
 573         if (0 <= v) {
 574                 *is_bool = 1;
 575                 return v;
 576         }
 577         *is_bool = 0;
 578         return git_config_int(name, value);
 579 }
 580
 581 int git_config_bool(const char *name, const char *value)
 582 {
 583         int discard;
 584         return !!git_config_bool_or_int(name, value, &discard);
 585 }
 586
 587 int git_config_string(const char **dest, const char *var, const char *value)
 588 {
 589         if (!value)
 590                 return config_error_nonbool(var);
 591         *dest = xstrdup(value);
 592         return 0;
 593 }
 594
 595 int git_config_pathname(const char **dest, const char *var, const char *value)
 596 {
 597         if (!value)
 598                 return config_error_nonbool(var);
 599         *dest = expand_user_path(value);
 600         if (!*dest)
 601                 die("Failed to expand user dir in: '%s'", value);
 602         return 0;
 603 }
 604
 605 static int git_default_core_config(const char *var, const char *value)
 606 {
 607         /* This needs a better name */
 608         if (!strcmp(var, "core.filemode")) {
 609                 trust_executable_bit = git_config_bool(var, value);
 610                 return 0;
 611         }
 612         if (!strcmp(var, "core.trustctime")) {
 613                 trust_ctime = git_config_bool(var, value);
 614                 return 0;
 615         }
 616         if (!strcmp(var, "core.statinfo") ||
 617             !strcmp(var, "core.checkstat")) {
 618                 /*
 619                  * NEEDSWORK: statinfo was a typo in v1.8.2 that has
 620                  * never been advertised.  we will remove it at Git
 621                  * 2.0 boundary.
 622                  */
 623                 if (!strcmp(var, "core.statinfo")) {
 624                         static int warned;
 625                         if (!warned++) {
 626                                 warning("'core.statinfo' will be removed in Git 2.0; "
 627                                         "use 'core.checkstat' instead.");
 628                         }
 629                 }
 630                 if (!strcasecmp(value, "default"))
 631                         check_stat = 1;
 632                 else if (!strcasecmp(value, "minimal"))
 633                         check_stat = 0;
 634         }
 635
 636         if (!strcmp(var, "core.quotepath")) {
 637                 quote_path_fully = git_config_bool(var, value);
 638                 return 0;
 639         }
 640
 641         if (!strcmp(var, "core.symlinks")) {
 642                 has_symlinks = git_config_bool(var, value);
 643                 return 0;
 644         }
 645
 646         if (!strcmp(var, "core.ignorecase")) {
 647                 ignore_case = git_config_bool(var, value);
 648                 return 0;
 649         }
 650
 651         if (!strcmp(var, "core.attributesfile"))
 652                 return git_config_pathname(&git_attributes_file, var, value);
 653
 654         if (!strcmp(var, "core.bare")) {
 655                 is_bare_repository_cfg = git_config_bool(var, value);
 656                 return 0;
 657         }
 658
 659         if (!strcmp(var, "core.ignorestat")) {
 660                 assume_unchanged = git_config_bool(var, value);
 661                 return 0;
 662         }
 663
 664         if (!strcmp(var, "core.prefersymlinkrefs")) {
 665                 prefer_symlink_refs = git_config_bool(var, value);
 666                 return 0;
 667         }
 668
 669         if (!strcmp(var, "core.logallrefupdates")) {
 670                 log_all_ref_updates = git_config_bool(var, value);
 671                 return 0;
 672         }
 673
 674         if (!strcmp(var, "core.warnambiguousrefs")) {
 675                 warn_ambiguous_refs = git_config_bool(var, value);
 676                 return 0;
 677         }
 678
 679         if (!strcmp(var, "core.abbrev")) {
 680                 int abbrev = git_config_int(var, value);
 681                 if (abbrev < minimum_abbrev || abbrev > 40)
 682                         return -1;
 683                 default_abbrev = abbrev;
 684                 return 0;
 685         }
 686
 687         if (!strcmp(var, "core.loosecompression")) {
 688                 int level = git_config_int(var, value);
 689                 if (level == -1)
 690                         level = Z_DEFAULT_COMPRESSION;
 691                 else if (level < 0 || level > Z_BEST_COMPRESSION)
 692                         die("bad zlib compression level %d", level);
 693                 zlib_compression_level = level;
 694                 zlib_compression_seen = 1;
 695                 return 0;
 696         }
 697
 698         if (!strcmp(var, "core.compression")) {
 699                 int level = git_config_int(var, value);
 700                 if (level == -1)
 701                         level = Z_DEFAULT_COMPRESSION;
 702                 else if (level < 0 || level > Z_BEST_COMPRESSION)
 703                         die("bad zlib compression level %d", level);
 704                 core_compression_level = level;
 705                 core_compression_seen = 1;
 706                 if (!zlib_compression_seen)
 707                         zlib_compression_level = level;
 708                 return 0;
 709         }
 710
 711         if (!strcmp(var, "core.packedgitwindowsize")) {
 712                 int pgsz_x2 = getpagesize() * 2;
 713                 packed_git_window_size = git_config_ulong(var, value);
 714
 715                 /* This value must be multiple of (pagesize * 2) */
 716                 packed_git_window_size /= pgsz_x2;
 717                 if (packed_git_window_size < 1)
 718                         packed_git_window_size = 1;
 719                 packed_git_window_size *= pgsz_x2;
 720                 return 0;
 721         }
 722
 723         if (!strcmp(var, "core.bigfilethreshold")) {
 724                 big_file_threshold = git_config_ulong(var, value);
 725                 return 0;
 726         }
 727
 728         if (!strcmp(var, "core.packedgitlimit")) {
 729                 packed_git_limit = git_config_ulong(var, value);
 730                 return 0;
 731         }
 732
 733         if (!strcmp(var, "core.deltabasecachelimit")) {
 734                 delta_base_cache_limit = git_config_ulong(var, value);
 735                 return 0;
 736         }
 737
 738         if (!strcmp(var, "core.autocrlf")) {
 739                 if (value && !strcasecmp(value, "input")) {
 740                         if (core_eol == EOL_CRLF)
 741                                 return error("core.autocrlf=input conflicts with core.eol=crlf");
 742                         auto_crlf = AUTO_CRLF_INPUT;
 743                         return 0;
 744                 }
 745                 auto_crlf = git_config_bool(var, value);
 746                 return 0;
 747         }
 748
 749         if (!strcmp(var, "core.safecrlf")) {
 750                 if (value && !strcasecmp(value, "warn")) {
 751                         safe_crlf = SAFE_CRLF_WARN;
 752                         return 0;
 753                 }
 754                 safe_crlf = git_config_bool(var, value);
 755                 return 0;
 756         }
 757
 758         if (!strcmp(var, "core.eol")) {
 759                 if (value && !strcasecmp(value, "lf"))
 760                         core_eol = EOL_LF;
 761                 else if (value && !strcasecmp(value, "crlf"))
 762                         core_eol = EOL_CRLF;
 763                 else if (value && !strcasecmp(value, "native"))
 764                         core_eol = EOL_NATIVE;
 765                 else
 766                         core_eol = EOL_UNSET;
 767                 if (core_eol == EOL_CRLF && auto_crlf == AUTO_CRLF_INPUT)
 768                         return error("core.autocrlf=input conflicts with core.eol=crlf");
 769                 return 0;
 770         }
 771
 772         if (!strcmp(var, "core.notesref")) {
 773                 notes_ref_name = xstrdup(value);
 774                 return 0;
 775         }
 776
 777         if (!strcmp(var, "core.pager"))
 778                 return git_config_string(&pager_program, var, value);
 779
 780         if (!strcmp(var, "core.editor"))
 781                 return git_config_string(&editor_program, var, value);
 782
 783         if (!strcmp(var, "core.commentchar")) {
 784                 const char *comment;
 785                 int ret = git_config_string(&comment, var, value);
 786                 if (!ret)
 787                         comment_line_char = comment[0];
 788                 return ret;
 789         }
 790
 791         if (!strcmp(var, "core.askpass"))
 792                 return git_config_string(&askpass_program, var, value);
 793
 794         if (!strcmp(var, "core.excludesfile"))
 795                 return git_config_pathname(&excludes_file, var, value);
 796
 797         if (!strcmp(var, "core.whitespace")) {
 798                 if (!value)
 799                         return config_error_nonbool(var);
 800                 whitespace_rule_cfg = parse_whitespace_rule(value);
 801                 return 0;
 802         }
 803
 804         if (!strcmp(var, "core.fsyncobjectfiles")) {
 805                 fsync_object_files = git_config_bool(var, value);
 806                 return 0;
 807         }
 808
 809         if (!strcmp(var, "core.preloadindex")) {
 810                 core_preload_index = git_config_bool(var, value);
 811                 return 0;
 812         }
 813
 814         if (!strcmp(var, "core.createobject")) {
 815                 if (!strcmp(value, "rename"))
 816                         object_creation_mode = OBJECT_CREATION_USES_RENAMES;
 817                 else if (!strcmp(value, "link"))
 818                         object_creation_mode = OBJECT_CREATION_USES_HARDLINKS;
 819                 else
 820                         die("Invalid mode for object creation: %s", value);
 821                 return 0;
 822         }
 823
 824         if (!strcmp(var, "core.sparsecheckout")) {
 825                 core_apply_sparse_checkout = git_config_bool(var, value);
 826                 return 0;
 827         }
 828
 829         if (!strcmp(var, "core.precomposeunicode")) {
 830                 precomposed_unicode = git_config_bool(var, value);
 831                 return 0;
 832         }
 833
 834         if (!strcmp(var, "core.hidedotfiles")) {
 835                 if (value && !strcasecmp(value, "dotgitonly")) {
 836                         hide_dotfiles = HIDE_DOTFILES_DOTGITONLY;
 837                         return 0;
 838                 }
 839                 hide_dotfiles = git_config_bool(var, value);
 840                 return 0;
 841         }
 842
 843         /* Add other config variables here and to Documentation/config.txt. */
 844         return 0;
 845 }
 846
 847 static int git_default_i18n_config(const char *var, const char *value)
 848 {
 849         if (!strcmp(var, "i18n.commitencoding"))
 850                 return git_config_string(&git_commit_encoding, var, value);
 851
 852         if (!strcmp(var, "i18n.logoutputencoding"))
 853                 return git_config_string(&git_log_output_encoding, var, value);
 854
 855         /* Add other config variables here and to Documentation/config.txt. */
 856         return 0;
 857 }
 858
 859 static int git_default_branch_config(const char *var, const char *value)
 860 {
 861         if (!strcmp(var, "branch.autosetupmerge")) {
 862                 if (value && !strcasecmp(value, "always")) {
 863                         git_branch_track = BRANCH_TRACK_ALWAYS;
 864                         return 0;
 865                 }
 866                 git_branch_track = git_config_bool(var, value);
 867                 return 0;
 868         }
 869         if (!strcmp(var, "branch.autosetuprebase")) {
 870                 if (!value)
 871                         return config_error_nonbool(var);
 872                 else if (!strcmp(value, "never"))
 873                         autorebase = AUTOREBASE_NEVER;
 874                 else if (!strcmp(value, "local"))
 875                         autorebase = AUTOREBASE_LOCAL;
 876                 else if (!strcmp(value, "remote"))
 877                         autorebase = AUTOREBASE_REMOTE;
 878                 else if (!strcmp(value, "always"))
 879                         autorebase = AUTOREBASE_ALWAYS;
 880                 else
 881                         return error("Malformed value for %s", var);
 882                 return 0;
 883         }
 884
 885         /* Add other config variables here and to Documentation/config.txt. */
 886         return 0;
 887 }
 888
 889 static int git_default_push_config(const char *var, const char *value)
 890 {
 891         if (!strcmp(var, "push.default")) {
 892                 if (!value)
 893                         return config_error_nonbool(var);
 894                 else if (!strcmp(value, "nothing"))
 895                         push_default = PUSH_DEFAULT_NOTHING;
 896                 else if (!strcmp(value, "matching"))
 897                         push_default = PUSH_DEFAULT_MATCHING;
 898                 else if (!strcmp(value, "simple"))
 899                         push_default = PUSH_DEFAULT_SIMPLE;
 900                 else if (!strcmp(value, "upstream"))
 901                         push_default = PUSH_DEFAULT_UPSTREAM;
 902                 else if (!strcmp(value, "tracking")) /* deprecated */
 903                         push_default = PUSH_DEFAULT_UPSTREAM;
 904                 else if (!strcmp(value, "current"))
 905                         push_default = PUSH_DEFAULT_CURRENT;
 906                 else {
 907                         error("Malformed value for %s: %s", var, value);
 908                         return error("Must be one of nothing, matching, simple, "
 909                                      "upstream or current.");
 910                 }
 911                 return 0;
 912         }
 913
 914         /* Add other config variables here and to Documentation/config.txt. */
 915         return 0;
 916 }
 917
 918 static int git_default_mailmap_config(const char *var, const char *value)
 919 {
 920         if (!strcmp(var, "mailmap.file"))
 921                 return git_config_string(&git_mailmap_file, var, value);
 922         if (!strcmp(var, "mailmap.blob"))
 923                 return git_config_string(&git_mailmap_blob, var, value);
 924
 925         /* Add other config variables here and to Documentation/config.txt. */
 926         return 0;
 927 }
 928
 929 int git_default_config(const char *var, const char *value, void *dummy)
 930 {
 931         if (!prefixcmp(var, "core."))
 932                 return git_default_core_config(var, value);
 933
 934         if (!prefixcmp(var, "user."))
 935                 return git_ident_config(var, value, dummy);
 936
 937         if (!prefixcmp(var, "i18n."))
 938                 return git_default_i18n_config(var, value);
 939
 940         if (!prefixcmp(var, "branch."))
 941                 return git_default_branch_config(var, value);
 942
 943         if (!prefixcmp(var, "push."))
 944                 return git_default_push_config(var, value);
 945
 946         if (!prefixcmp(var, "mailmap."))
 947                 return git_default_mailmap_config(var, value);
 948
 949         if (!prefixcmp(var, "advice."))
 950                 return git_default_advice_config(var, value);
 951
 952         if (!strcmp(var, "pager.color") || !strcmp(var, "color.pager")) {
 953                 pager_use_color = git_config_bool(var,value);
 954                 return 0;
 955         }
 956
 957         if (!strcmp(var, "pack.packsizelimit")) {
 958                 pack_size_limit_cfg = git_config_ulong(var, value);
 959                 return 0;
 960         }
 961         /* Add other config variables here and to Documentation/config.txt. */
 962         return 0;
 963 }
 964
 965 /*
 966  * All source specific fields in the union, die_on_error, name and the callbacks
 967  * fgetc, ungetc, ftell of top need to be initialized before calling
 968  * this function.
 969  */
 970 static int do_config_from(struct config_source *top, config_fn_t fn, void *data)
 971 {
 972         int ret;
 973
 974         /* push config-file parsing state stack */
 975         top->prev = cf;
 976         top->linenr = 1;
 977         top->eof = 0;
 978         strbuf_init(&top->value, 1024);
 979         strbuf_init(&top->var, 1024);
 980         cf = top;
 981
 982         ret = git_parse_source(fn, data);
 983
 984         /* pop config-file parsing state stack */
 985         strbuf_release(&top->value);
 986         strbuf_release(&top->var);
 987         cf = top->prev;
 988
 989         return ret;
 990 }
 991
 992 int git_config_from_file(config_fn_t fn, const char *filename, void *data)
 993 {
 994         int ret;
 995         FILE *f = fopen(filename, "r");
 996
 997         ret = -1;
 998         if (f) {
 999                 struct config_source top;
1000
1001                 top.u.file = f;
1002                 top.name = filename;
1003                 top.die_on_error = 1;
1004                 top.fgetc = config_file_fgetc;
1005                 top.ungetc = config_file_ungetc;
1006                 top.ftell = config_file_ftell;
1007
1008                 ret = do_config_from(&top, fn, data);
1009
1010                 fclose(f);
1011         }
1012         return ret;
1013 }
1014
1015 int git_config_from_buf(config_fn_t fn, const char *name, const char *buf,
1016                         size_t len, void *data)
1017 {
1018         struct config_source top;
1019
1020         top.u.buf.buf = buf;
1021         top.u.buf.len = len;
1022         top.u.buf.pos = 0;
1023         top.name = name;
1024         top.die_on_error = 0;
1025         top.fgetc = config_buf_fgetc;
1026         top.ungetc = config_buf_ungetc;
1027         top.ftell = config_buf_ftell;
1028
1029         return do_config_from(&top, fn, data);
1030 }
1031
1032 static int git_config_from_blob_sha1(config_fn_t fn,
1033                                      const char *name,
1034                                      const unsigned char *sha1,
1035                                      void *data)
1036 {
1037         enum object_type type;
1038         char *buf;
1039         unsigned long size;
1040         int ret;
1041
1042         buf = read_sha1_file(sha1, &type, &size);
1043         if (!buf)
1044                 return error("unable to load config blob object '%s'", name);
1045         if (type != OBJ_BLOB) {
1046                 free(buf);
1047                 return error("reference '%s' does not point to a blob", name);
1048         }
1049
1050         ret = git_config_from_buf(fn, name, buf, size, data);
1051         free(buf);
1052
1053         return ret;
1054 }
1055
1056 static int git_config_from_blob_ref(config_fn_t fn,
1057                                     const char *name,
1058                                     void *data)
1059 {
1060         unsigned char sha1[20];
1061
1062         if (get_sha1(name, sha1) < 0)
1063                 return error("unable to resolve config blob '%s'", name);
1064         return git_config_from_blob_sha1(fn, name, sha1, data);
1065 }
1066
1067 const char *git_etc_gitconfig(void)
1068 {
1069         static const char *system_wide;
1070         if (!system_wide)
1071                 system_wide = system_path(ETC_GITCONFIG);
1072         return system_wide;
1073 }
1074
1075 int git_env_bool(const char *k, int def)
1076 {
1077         const char *v = getenv(k);
1078         return v ? git_config_bool(k, v) : def;
1079 }
1080
1081 int git_config_system(void)
1082 {
1083         return !git_env_bool("GIT_CONFIG_NOSYSTEM", 0);
1084 }
1085
1086 int git_config_early(config_fn_t fn, void *data, const char *repo_config)
1087 {
1088         int ret = 0, found = 0;
1089         char *xdg_config = NULL;
1090         char *user_config = NULL;
1091
1092         home_config_paths(&user_config, &xdg_config, "config");
1093
1094         if (git_config_system() && !access_or_die(git_etc_gitconfig(), R_OK, 0)) {
1095                 ret += git_config_from_file(fn, git_etc_gitconfig(),
1096                                             data);
1097                 found += 1;
1098         }
1099
1100         if (xdg_config && !access_or_die(xdg_config, R_OK, ACCESS_EACCES_OK)) {
1101                 ret += git_config_from_file(fn, xdg_config, data);
1102                 found += 1;
1103         }
1104
1105         if (user_config && !access_or_die(user_config, R_OK, ACCESS_EACCES_OK)) {
1106                 ret += git_config_from_file(fn, user_config, data);
1107                 found += 1;
1108         }
1109
1110         if (repo_config && !access_or_die(repo_config, R_OK, 0)) {
1111                 ret += git_config_from_file(fn, repo_config, data);
1112                 found += 1;
1113         }
1114
1115         switch (git_config_from_parameters(fn, data)) {
1116         case -1: /* error */
1117                 die("unable to parse command-line config");
1118                 break;
1119         case 0: /* found nothing */
1120                 break;
1121         default: /* found at least one item */
1122                 found++;
1123                 break;
1124         }
1125
1126         free(xdg_config);
1127         free(user_config);
1128         return ret == 0 ? found : ret;
1129 }
1130
1131 int git_config_with_options(config_fn_t fn, void *data,
1132                             const char *filename,
1133                             const char *blob_ref,
1134                             int respect_includes)
1135 {
1136         char *repo_config = NULL;
1137         int ret;
1138         struct config_include_data inc = CONFIG_INCLUDE_INIT;
1139
1140         if (respect_includes) {
1141                 inc.fn = fn;
1142                 inc.data = data;
1143                 fn = git_config_include;
1144                 data = &inc;
1145         }
1146
1147         /*
1148          * If we have a specific filename, use it. Otherwise, follow the
1149          * regular lookup sequence.
1150          */
1151         if (filename)
1152                 return git_config_from_file(fn, filename, data);
1153         else if (blob_ref)
1154                 return git_config_from_blob_ref(fn, blob_ref, data);
1155
1156         repo_config = git_pathdup("config");
1157         ret = git_config_early(fn, data, repo_config);
1158         if (repo_config)
1159                 free(repo_config);
1160         return ret;
1161 }
1162
1163 int git_config(config_fn_t fn, void *data)
1164 {
1165         return git_config_with_options(fn, data, NULL, NULL, 1);
1166 }
1167
1168 /*
1169  * Find all the stuff for git_config_set() below.
1170  */
1171
1172 #define MAX_MATCHES 512
1173
1174 static struct {
1175         int baselen;
1176         char *key;
1177         int do_not_match;
1178         regex_t *value_regex;
1179         int multi_replace;
1180         size_t offset[MAX_MATCHES];
1181         enum { START, SECTION_SEEN, SECTION_END_SEEN, KEY_SEEN } state;
1182         int seen;
1183 } store;
1184
1185 static int matches(const char *key, const char *value)
1186 {
1187         return !strcmp(key, store.key) &&
1188                 (store.value_regex == NULL ||
1189                  (store.do_not_match ^
1190                   !regexec(store.value_regex, value, 0, NULL, 0)));
1191 }
1192
1193 static int store_aux(const char *key, const char *value, void *cb)
1194 {
1195         const char *ep;
1196         size_t section_len;
1197
1198         switch (store.state) {
1199         case KEY_SEEN:
1200                 if (matches(key, value)) {
1201                         if (store.seen == 1 && store.multi_replace == 0) {
1202                                 warning("%s has multiple values", key);
1203                         } else if (store.seen >= MAX_MATCHES) {
1204                                 error("too many matches for %s", key);
1205                                 return 1;
1206                         }
1207
1208                         store.offset[store.seen] = cf->ftell(cf);
1209                         store.seen++;
1210                 }
1211                 break;
1212         case SECTION_SEEN:
1213                 /*
1214                  * What we are looking for is in store.key (both
1215                  * section and var), and its section part is baselen
1216                  * long.  We found key (again, both section and var).
1217                  * We would want to know if this key is in the same
1218                  * section as what we are looking for.  We already
1219                  * know we are in the same section as what should
1220                  * hold store.key.
1221                  */
1222                 ep = strrchr(key, '.');
1223                 section_len = ep - key;
1224
1225                 if ((section_len != store.baselen) ||
1226                     memcmp(key, store.key, section_len+1)) {
1227                         store.state = SECTION_END_SEEN;
1228                         break;
1229                 }
1230
1231                 /*
1232                  * Do not increment matches: this is no match, but we
1233                  * just made sure we are in the desired section.
1234                  */
1235                 store.offset[store.seen] = cf->ftell(cf);
1236                 /* fallthru */
1237         case SECTION_END_SEEN:
1238         case START:
1239                 if (matches(key, value)) {
1240                         store.offset[store.seen] = cf->ftell(cf);
1241                         store.state = KEY_SEEN;
1242                         store.seen++;
1243                 } else {
1244                         if (strrchr(key, '.') - key == store.baselen &&
1245                               !strncmp(key, store.key, store.baselen)) {
1246                                         store.state = SECTION_SEEN;
1247                                         store.offset[store.seen] = cf->ftell(cf);
1248                         }
1249                 }
1250         }
1251         return 0;
1252 }
1253
1254 static int write_error(const char *filename)
1255 {
1256         error("failed to write new configuration file %s", filename);
1257
1258         /* Same error code as "failed to rename". */
1259         return 4;
1260 }
1261
1262 static int store_write_section(int fd, const char *key)
1263 {
1264         const char *dot;
1265         int i, success;
1266         struct strbuf sb = STRBUF_INIT;
1267
1268         dot = memchr(key, '.', store.baselen);
1269         if (dot) {
1270                 strbuf_addf(&sb, "[%.*s \"", (int)(dot - key), key);
1271                 for (i = dot - key + 1; i < store.baselen; i++) {
1272                         if (key[i] == '"' || key[i] == '\\')
1273                                 strbuf_addch(&sb, '\\');
1274                         strbuf_addch(&sb, key[i]);
1275                 }
1276                 strbuf_addstr(&sb, "\"]\n");
1277         } else {
1278                 strbuf_addf(&sb, "[%.*s]\n", store.baselen, key);
1279         }
1280
1281         success = write_in_full(fd, sb.buf, sb.len) == sb.len;
1282         strbuf_release(&sb);
1283
1284         return success;
1285 }
1286
1287 static int store_write_pair(int fd, const char *key, const char *value)
1288 {
1289         int i, success;
1290         int length = strlen(key + store.baselen + 1);
1291         const char *quote = "";
1292         struct strbuf sb = STRBUF_INIT;
1293
1294         /*
1295          * Check to see if the value needs to be surrounded with a dq pair.
1296          * Note that problematic characters are always backslash-quoted; this
1297          * check is about not losing leading or trailing SP and strings that
1298          * follow beginning-of-comment characters (i.e. ';' and '#') by the
1299          * configuration parser.
1300          */
1301         if (value[0] == ' ')
1302                 quote = "\"";
1303         for (i = 0; value[i]; i++)
1304                 if (value[i] == ';' || value[i] == '#')
1305                         quote = "\"";
1306         if (i && value[i - 1] == ' ')
1307                 quote = "\"";
1308
1309         strbuf_addf(&sb, "\t%.*s = %s",
1310                     length, key + store.baselen + 1, quote);
1311
1312         for (i = 0; value[i]; i++)
1313                 switch (value[i]) {
1314                 case '\n':
1315                         strbuf_addstr(&sb, "\\n");
1316                         break;
1317                 case '\t':
1318                         strbuf_addstr(&sb, "\\t");
1319                         break;
1320                 case '"':
1321                 case '\\':
1322                         strbuf_addch(&sb, '\\');
1323                 default:
1324                         strbuf_addch(&sb, value[i]);
1325                         break;
1326                 }
1327         strbuf_addf(&sb, "%s\n", quote);
1328
1329         success = write_in_full(fd, sb.buf, sb.len) == sb.len;
1330         strbuf_release(&sb);
1331
1332         return success;
1333 }
1334
1335 static ssize_t find_beginning_of_line(const char *contents, size_t size,
1336         size_t offset_, int *found_bracket)
1337 {
1338         size_t equal_offset = size, bracket_offset = size;
1339         ssize_t offset;
1340
1341 contline:
1342         for (offset = offset_-2; offset > 0
1343                         && contents[offset] != '\n'; offset--)
1344                 switch (contents[offset]) {
1345                         case '=': equal_offset = offset; break;
1346                         case ']': bracket_offset = offset; break;
1347                 }
1348         if (offset > 0 && contents[offset-1] == '\\') {
1349                 offset_ = offset;
1350                 goto contline;
1351         }
1352         if (bracket_offset < equal_offset) {
1353                 *found_bracket = 1;
1354                 offset = bracket_offset+1;
1355         } else
1356                 offset++;
1357
1358         return offset;
1359 }
1360
1361 int git_config_set_in_file(const char *config_filename,
1362                         const char *key, const char *value)
1363 {
1364         return git_config_set_multivar_in_file(config_filename, key, value, NULL, 0);
1365 }
1366
1367 int git_config_set(const char *key, const char *value)
1368 {
1369         return git_config_set_multivar(key, value, NULL, 0);
1370 }
1371
1372 /*
1373  * Auxiliary function to sanity-check and split the key into the section
1374  * identifier and variable name.
1375  *
1376  * Returns 0 on success, -1 when there is an invalid character in the key and
1377  * -2 if there is no section name in the key.
1378  *
1379  * store_key - pointer to char* which will hold a copy of the key with
1380  *             lowercase section and variable name
1381  * baselen - pointer to int which will hold the length of the
1382  *           section + subsection part, can be NULL
1383  */
1384 int git_config_parse_key(const char *key, char **store_key, int *baselen_)
1385 {
1386         int i, dot, baselen;
1387         const char *last_dot = strrchr(key, '.');
1388
1389         /*
1390          * Since "key" actually contains the section name and the real
1391          * key name separated by a dot, we have to know where the dot is.
1392          */
1393
1394         if (last_dot == NULL || last_dot == key) {
1395                 error("key does not contain a section: %s", key);
1396                 return -CONFIG_NO_SECTION_OR_NAME;
1397         }
1398
1399         if (!last_dot[1]) {
1400                 error("key does not contain variable name: %s", key);
1401                 return -CONFIG_NO_SECTION_OR_NAME;
1402         }
1403
1404         baselen = last_dot - key;
1405         if (baselen_)
1406                 *baselen_ = baselen;
1407
1408         /*
1409          * Validate the key and while at it, lower case it for matching.
1410          */
1411         *store_key = xmalloc(strlen(key) + 1);
1412
1413         dot = 0;
1414         for (i = 0; key[i]; i++) {
1415                 unsigned char c = key[i];
1416                 if (c == '.')
1417                         dot = 1;
1418                 /* Leave the extended basename untouched.. */
1419                 if (!dot || i > baselen) {
1420                         if (!iskeychar(c) ||
1421                             (i == baselen + 1 && !isalpha(c))) {
1422                                 error("invalid key: %s", key);
1423                                 goto out_free_ret_1;
1424                         }
1425                         c = tolower(c);
1426                 } else if (c == '\n') {
1427                         error("invalid key (newline): %s", key);
1428                         goto out_free_ret_1;
1429                 }
1430                 (*store_key)[i] = c;
1431         }
1432         (*store_key)[i] = 0;
1433
1434         return 0;
1435
1436 out_free_ret_1:
1437         free(*store_key);
1438         *store_key = NULL;
1439         return -CONFIG_INVALID_KEY;
1440 }
1441
1442 /*
1443  * If value==NULL, unset in (remove from) config,
1444  * if value_regex!=NULL, disregard key/value pairs where value does not match.
1445  * if multi_replace==0, nothing, or only one matching key/value is replaced,
1446  *     else all matching key/values (regardless how many) are removed,
1447  *     before the new pair is written.
1448  *
1449  * Returns 0 on success.
1450  *
1451  * This function does this:
1452  *
1453  * - it locks the config file by creating ".git/config.lock"
1454  *
1455  * - it then parses the config using store_aux() as validator to find
1456  *   the position on the key/value pair to replace. If it is to be unset,
1457  *   it must be found exactly once.
1458  *
1459  * - the config file is mmap()ed and the part before the match (if any) is
1460  *   written to the lock file, then the changed part and the rest.
1461  *
1462  * - the config file is removed and the lock file rename()d to it.
1463  *
1464  */
1465 int git_config_set_multivar_in_file(const char *config_filename,
1466                                 const char *key, const char *value,
1467                                 const char *value_regex, int multi_replace)
1468 {
1469         int fd = -1, in_fd;
1470         int ret;
1471         struct lock_file *lock = NULL;
1472         char *filename_buf = NULL;
1473
1474         /* parse-key returns negative; flip the sign to feed exit(3) */
1475         ret = 0 - git_config_parse_key(key, &store.key, &store.baselen);
1476         if (ret)
1477                 goto out_free;
1478
1479         store.multi_replace = multi_replace;
1480
1481         if (!config_filename)
1482                 config_filename = filename_buf = git_pathdup("config");
1483
1484         /*
1485          * The lock serves a purpose in addition to locking: the new
1486          * contents of .git/config will be written into it.
1487          */
1488         lock = xcalloc(sizeof(struct lock_file), 1);
1489         fd = hold_lock_file_for_update(lock, config_filename, 0);
1490         if (fd < 0) {
1491                 error("could not lock config file %s: %s", config_filename, strerror(errno));
1492                 free(store.key);
1493                 ret = CONFIG_NO_LOCK;
1494                 goto out_free;
1495         }
1496
1497         /*
1498          * If .git/config does not exist yet, write a minimal version.
1499          */
1500         in_fd = open(config_filename, O_RDONLY);
1501         if ( in_fd < 0 ) {
1502                 free(store.key);
1503
1504                 if ( ENOENT != errno ) {
1505                         error("opening %s: %s", config_filename,
1506                               strerror(errno));
1507                         ret = CONFIG_INVALID_FILE; /* same as "invalid config file" */
1508                         goto out_free;
1509                 }
1510                 /* if nothing to unset, error out */
1511                 if (value == NULL) {
1512                         ret = CONFIG_NOTHING_SET;
1513                         goto out_free;
1514                 }
1515
1516                 store.key = (char *)key;
1517                 if (!store_write_section(fd, key) ||
1518                     !store_write_pair(fd, key, value))
1519                         goto write_err_out;
1520         } else {
1521                 struct stat st;
1522                 char *contents;
1523                 size_t contents_sz, copy_begin, copy_end;
1524                 int i, new_line = 0;
1525
1526                 if (value_regex == NULL)
1527                         store.value_regex = NULL;
1528                 else {
1529                         if (value_regex[0] == '!') {
1530                                 store.do_not_match = 1;
1531                                 value_regex++;
1532                         } else
1533                                 store.do_not_match = 0;
1534
1535                         store.value_regex = (regex_t*)xmalloc(sizeof(regex_t));
1536                         if (regcomp(store.value_regex, value_regex,
1537                                         REG_EXTENDED)) {
1538                                 error("invalid pattern: %s", value_regex);
1539                                 free(store.value_regex);
1540                                 ret = CONFIG_INVALID_PATTERN;
1541                                 goto out_free;
1542                         }
1543                 }
1544
1545                 store.offset[0] = 0;
1546                 store.state = START;
1547                 store.seen = 0;
1548
1549                 /*
1550                  * After this, store.offset will contain the *end* offset
1551                  * of the last match, or remain at 0 if no match was found.
1552                  * As a side effect, we make sure to transform only a valid
1553                  * existing config file.
1554                  */
1555                 if (git_config_from_file(store_aux, config_filename, NULL)) {
1556                         error("invalid config file %s", config_filename);
1557                         free(store.key);
1558                         if (store.value_regex != NULL) {
1559                                 regfree(store.value_regex);
1560                                 free(store.value_regex);
1561                         }
1562                         ret = CONFIG_INVALID_FILE;
1563                         goto out_free;
1564                 }
1565
1566                 free(store.key);
1567                 if (store.value_regex != NULL) {
1568                         regfree(store.value_regex);
1569                         free(store.value_regex);
1570                 }
1571
1572                 /* if nothing to unset, or too many matches, error out */
1573                 if ((store.seen == 0 && value == NULL) ||
1574                                 (store.seen > 1 && multi_replace == 0)) {
1575                         ret = CONFIG_NOTHING_SET;
1576                         goto out_free;
1577                 }
1578
1579                 fstat(in_fd, &st);
1580                 contents_sz = xsize_t(st.st_size);
1581                 contents = xmmap(NULL, contents_sz, PROT_READ,
1582                         MAP_PRIVATE, in_fd, 0);
1583                 close(in_fd);
1584
1585                 if (store.seen == 0)
1586                         store.seen = 1;
1587
1588                 for (i = 0, copy_begin = 0; i < store.seen; i++) {
1589                         if (store.offset[i] == 0) {
1590                                 store.offset[i] = copy_end = contents_sz;
1591                         } else if (store.state != KEY_SEEN) {
1592                                 copy_end = store.offset[i];
1593                         } else
1594                                 copy_end = find_beginning_of_line(
1595                                         contents, contents_sz,
1596                                         store.offset[i]-2, &new_line);
1597
1598                         if (copy_end > 0 && contents[copy_end-1] != '\n')
1599                                 new_line = 1;
1600
1601                         /* write the first part of the config */
1602                         if (copy_end > copy_begin) {
1603                                 if (write_in_full(fd, contents + copy_begin,
1604                                                   copy_end - copy_begin) <
1605                                     copy_end - copy_begin)
1606                                         goto write_err_out;
1607                                 if (new_line &&
1608                                     write_str_in_full(fd, "\n") != 1)
1609                                         goto write_err_out;
1610                         }
1611                         copy_begin = store.offset[i];
1612                 }
1613
1614                 /* write the pair (value == NULL means unset) */
1615                 if (value != NULL) {
1616                         if (store.state == START) {
1617                                 if (!store_write_section(fd, key))
1618                                         goto write_err_out;
1619                         }
1620                         if (!store_write_pair(fd, key, value))
1621                                 goto write_err_out;
1622                 }
1623
1624                 /* write the rest of the config */
1625                 if (copy_begin < contents_sz)
1626                         if (write_in_full(fd, contents + copy_begin,
1627                                           contents_sz - copy_begin) <
1628                             contents_sz - copy_begin)
1629                                 goto write_err_out;
1630
1631                 munmap(contents, contents_sz);
1632         }
1633
1634         if (commit_lock_file(lock) < 0) {
1635                 error("could not commit config file %s", config_filename);
1636                 ret = CONFIG_NO_WRITE;
1637                 goto out_free;
1638         }
1639
1640         /*
1641          * lock is committed, so don't try to roll it back below.
1642          * NOTE: Since lockfile.c keeps a linked list of all created
1643          * lock_file structures, it isn't safe to free(lock).  It's
1644          * better to just leave it hanging around.
1645          */
1646         lock = NULL;
1647         ret = 0;
1648
1649 out_free:
1650         if (lock)
1651                 rollback_lock_file(lock);
1652         free(filename_buf);
1653         return ret;
1654
1655 write_err_out:
1656         ret = write_error(lock->filename);
1657         goto out_free;
1658
1659 }
1660
1661 int git_config_set_multivar(const char *key, const char *value,
1662                         const char *value_regex, int multi_replace)
1663 {
1664         return git_config_set_multivar_in_file(NULL, key, value, value_regex,
1665                                                multi_replace);
1666 }
1667
1668 static int section_name_match (const char *buf, const char *name)
1669 {
1670         int i = 0, j = 0, dot = 0;
1671         if (buf[i] != '[')
1672                 return 0;
1673         for (i = 1; buf[i] && buf[i] != ']'; i++) {
1674                 if (!dot && isspace(buf[i])) {
1675                         dot = 1;
1676                         if (name[j++] != '.')
1677                                 break;
1678                         for (i++; isspace(buf[i]); i++)
1679                                 ; /* do nothing */
1680                         if (buf[i] != '"')
1681                                 break;
1682                         continue;
1683                 }
1684                 if (buf[i] == '\\' && dot)
1685                         i++;
1686                 else if (buf[i] == '"' && dot) {
1687                         for (i++; isspace(buf[i]); i++)
1688                                 ; /* do_nothing */
1689                         break;
1690                 }
1691                 if (buf[i] != name[j++])
1692                         break;
1693         }
1694         if (buf[i] == ']' && name[j] == 0) {
1695                 /*
1696                  * We match, now just find the right length offset by
1697                  * gobbling up any whitespace after it, as well
1698                  */
1699                 i++;
1700                 for (; buf[i] && isspace(buf[i]); i++)
1701                         ; /* do nothing */
1702                 return i;
1703         }
1704         return 0;
1705 }
1706
1707 static int section_name_is_ok(const char *name)
1708 {
1709         /* Empty section names are bogus. */
1710         if (!*name)
1711                 return 0;
1712
1713         /*
1714          * Before a dot, we must be alphanumeric or dash. After the first dot,
1715          * anything goes, so we can stop checking.
1716          */
1717         for (; *name && *name != '.'; name++)
1718                 if (*name != '-' && !isalnum(*name))
1719                         return 0;
1720         return 1;
1721 }
1722
1723 /* if new_name == NULL, the section is removed instead */
1724 int git_config_rename_section_in_file(const char *config_filename,
1725                                       const char *old_name, const char *new_name)
1726 {
1727         int ret = 0, remove = 0;
1728         char *filename_buf = NULL;
1729         struct lock_file *lock;
1730         int out_fd;
1731         char buf[1024];
1732         FILE *config_file;
1733
1734         if (new_name && !section_name_is_ok(new_name)) {
1735                 ret = error("invalid section name: %s", new_name);
1736                 goto out;
1737         }
1738
1739         if (!config_filename)
1740                 config_filename = filename_buf = git_pathdup("config");
1741
1742         lock = xcalloc(sizeof(struct lock_file), 1);
1743         out_fd = hold_lock_file_for_update(lock, config_filename, 0);
1744         if (out_fd < 0) {
1745                 ret = error("could not lock config file %s", config_filename);
1746                 goto out;
1747         }
1748
1749         if (!(config_file = fopen(config_filename, "rb"))) {
1750                 /* no config file means nothing to rename, no error */
1751                 goto unlock_and_out;
1752         }
1753
1754         while (fgets(buf, sizeof(buf), config_file)) {
1755                 int i;
1756                 int length;
1757                 char *output = buf;
1758                 for (i = 0; buf[i] && isspace(buf[i]); i++)
1759                         ; /* do nothing */
1760                 if (buf[i] == '[') {
1761                         /* it's a section */
1762                         int offset = section_name_match(&buf[i], old_name);
1763                         if (offset > 0) {
1764                                 ret++;
1765                                 if (new_name == NULL) {
1766                                         remove = 1;
1767                                         continue;
1768                                 }
1769                                 store.baselen = strlen(new_name);
1770                                 if (!store_write_section(out_fd, new_name)) {
1771                                         ret = write_error(lock->filename);
1772                                         goto out;
1773                                 }
1774                                 /*
1775                                  * We wrote out the new section, with
1776                                  * a newline, now skip the old
1777                                  * section's length
1778                                  */
1779                                 output += offset + i;
1780                                 if (strlen(output) > 0) {
1781                                         /*
1782                                          * More content means there's
1783                                          * a declaration to put on the
1784                                          * next line; indent with a
1785                                          * tab
1786                                          */
1787                                         output -= 1;
1788                                         output[0] = '\t';
1789                                 }
1790                         }
1791                         remove = 0;
1792                 }
1793                 if (remove)
1794                         continue;
1795                 length = strlen(output);
1796                 if (write_in_full(out_fd, output, length) != length) {
1797                         ret = write_error(lock->filename);
1798                         goto out;
1799                 }
1800         }
1801         fclose(config_file);
1802 unlock_and_out:
1803         if (commit_lock_file(lock) < 0)
1804                 ret = error("could not commit config file %s", config_filename);
1805 out:
1806         free(filename_buf);
1807         return ret;
1808 }
1809
1810 int git_config_rename_section(const char *old_name, const char *new_name)
1811 {
1812         return git_config_rename_section_in_file(NULL, old_name, new_name);
1813 }
1814
1815 /*
1816  * Call this to report error for your variable that should not
1817  * get a boolean value (i.e. "[my] var" means "true").
1818  */
1819 #undef config_error_nonbool
1820 int config_error_nonbool(const char *var)
1821 {
1822         return error("Missing value for '%s'", var);
1823 }
1824
1825 int parse_config_key(const char *var,
1826                      const char *section,
1827                      const char **subsection, int *subsection_len,
1828                      const char **key)
1829 {
1830         int section_len = strlen(section);
1831         const char *dot;
1832
1833         /* Does it start with "section." ? */
1834         if (prefixcmp(var, section) || var[section_len] != '.')
1835                 return -1;
1836
1837         /*
1838          * Find the key; we don't know yet if we have a subsection, but we must
1839          * parse backwards from the end, since the subsection may have dots in
1840          * it, too.
1841          */
1842         dot = strrchr(var, '.');
1843         *key = dot + 1;
1844
1845         /* Did we have a subsection at all? */
1846         if (dot == var + section_len) {
1847                 *subsection = NULL;
1848                 *subsection_len = 0;
1849         }
1850         else {
1851                 *subsection = var + section_len + 1;
1852                 *subsection_len = dot - *subsection;
1853         }
1854
1855         return 0;
1856 }