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         const char *path;
  25         int die_on_error;
  26         int linenr;
  27         int eof;
  28         struct strbuf value;
  29         struct strbuf var;
  30
  31         int (*do_fgetc)(struct config_source *c);
  32         int (*do_ungetc)(int c, struct config_source *conf);
  33         long (*do_ftell)(struct config_source *c);
  34 };
  35
  36 static struct config_source *cf;
  37
  38 static int zlib_compression_seen;
  39
  40 static int config_file_fgetc(struct config_source *conf)
  41 {
  42         return fgetc(conf->u.file);
  43 }
  44
  45 static int config_file_ungetc(int c, struct config_source *conf)
  46 {
  47         return ungetc(c, conf->u.file);
  48 }
  49
  50 static long config_file_ftell(struct config_source *conf)
  51 {
  52         return ftell(conf->u.file);
  53 }
  54
  55
  56 static int config_buf_fgetc(struct config_source *conf)
  57 {
  58         if (conf->u.buf.pos < conf->u.buf.len)
  59                 return conf->u.buf.buf[conf->u.buf.pos++];
  60
  61         return EOF;
  62 }
  63
  64 static int config_buf_ungetc(int c, struct config_source *conf)
  65 {
  66         if (conf->u.buf.pos > 0)
  67                 return conf->u.buf.buf[--conf->u.buf.pos];
  68
  69         return EOF;
  70 }
  71
  72 static long config_buf_ftell(struct config_source *conf)
  73 {
  74         return conf->u.buf.pos;
  75 }
  76
  77 #define MAX_INCLUDE_DEPTH 10
  78 static const char include_depth_advice[] =
  79 "exceeded maximum include depth (%d) while including\n"
  80 "       %s\n"
  81 "from\n"
  82 "       %s\n"
  83 "Do you have circular includes?";
  84 static int handle_path_include(const char *path, struct config_include_data *inc)
  85 {
  86         int ret = 0;
  87         struct strbuf buf = STRBUF_INIT;
  88         char *expanded;
  89
  90         if (!path)
  91                 return config_error_nonbool("include.path");
  92
  93         expanded = expand_user_path(path);
  94         if (!expanded)
  95                 return error("Could not expand include path '%s'", path);
  96         path = expanded;
  97
  98         /*
  99          * Use an absolute path as-is, but interpret relative paths
 100          * based on the including config file.
 101          */
 102         if (!is_absolute_path(path)) {
 103                 char *slash;
 104
 105                 if (!cf || !cf->path)
 106                         return error("relative config includes must come from files");
 107
 108                 slash = find_last_dir_sep(cf->path);
 109                 if (slash)
 110                         strbuf_add(&buf, cf->path, slash - cf->path + 1);
 111                 strbuf_addstr(&buf, path);
 112                 path = buf.buf;
 113         }
 114
 115         if (!access_or_die(path, R_OK, 0)) {
 116                 if (++inc->depth > MAX_INCLUDE_DEPTH)
 117                         die(include_depth_advice, MAX_INCLUDE_DEPTH, path,
 118                             cf && cf->name ? cf->name : "the command line");
 119                 ret = git_config_from_file(git_config_include, path, inc);
 120                 inc->depth--;
 121         }
 122         strbuf_release(&buf);
 123         free(expanded);
 124         return ret;
 125 }
 126
 127 int git_config_include(const char *var, const char *value, void *data)
 128 {
 129         struct config_include_data *inc = data;
 130         const char *type;
 131         int ret;
 132
 133         /*
 134          * Pass along all values, including "include" directives; this makes it
 135          * possible to query information on the includes themselves.
 136          */
 137         ret = inc->fn(var, value, inc->data);
 138         if (ret < 0)
 139                 return ret;
 140
 141         type = skip_prefix(var, "include.");
 142         if (!type)
 143                 return ret;
 144
 145         if (!strcmp(type, "path"))
 146                 ret = handle_path_include(value, inc);
 147         return ret;
 148 }
 149
 150 static void lowercase(char *p)
 151 {
 152         for (; *p; p++)
 153                 *p = tolower(*p);
 154 }
 155
 156 void git_config_push_parameter(const char *text)
 157 {
 158         struct strbuf env = STRBUF_INIT;
 159         const char *old = getenv(CONFIG_DATA_ENVIRONMENT);
 160         if (old) {
 161                 strbuf_addstr(&env, old);
 162                 strbuf_addch(&env, ' ');
 163         }
 164         sq_quote_buf(&env, text);
 165         setenv(CONFIG_DATA_ENVIRONMENT, env.buf, 1);
 166         strbuf_release(&env);
 167 }
 168
 169 int git_config_parse_parameter(const char *text,
 170                                config_fn_t fn, void *data)
 171 {
 172         struct strbuf **pair;
 173         pair = strbuf_split_str(text, '=', 2);
 174         if (!pair[0])
 175                 return error("bogus config parameter: %s", text);
 176         if (pair[0]->len && pair[0]->buf[pair[0]->len - 1] == '=')
 177                 strbuf_setlen(pair[0], pair[0]->len - 1);
 178         strbuf_trim(pair[0]);
 179         if (!pair[0]->len) {
 180                 strbuf_list_free(pair);
 181                 return error("bogus config parameter: %s", text);
 182         }
 183         lowercase(pair[0]->buf);
 184         if (fn(pair[0]->buf, pair[1] ? pair[1]->buf : NULL, data) < 0) {
 185                 strbuf_list_free(pair);
 186                 return -1;
 187         }
 188         strbuf_list_free(pair);
 189         return 0;
 190 }
 191
 192 int git_config_from_parameters(config_fn_t fn, void *data)
 193 {
 194         const char *env = getenv(CONFIG_DATA_ENVIRONMENT);
 195         char *envw;
 196         const char **argv = NULL;
 197         int nr = 0, alloc = 0;
 198         int i;
 199
 200         if (!env)
 201                 return 0;
 202         /* sq_dequote will write over it */
 203         envw = xstrdup(env);
 204
 205         if (sq_dequote_to_argv(envw, &argv, &nr, &alloc) < 0) {
 206                 free(envw);
 207                 return error("bogus format in " CONFIG_DATA_ENVIRONMENT);
 208         }
 209
 210         for (i = 0; i < nr; i++) {
 211                 if (git_config_parse_parameter(argv[i], fn, data) < 0) {
 212                         free(argv);
 213                         free(envw);
 214                         return -1;
 215                 }
 216         }
 217
 218         free(argv);
 219         free(envw);
 220         return nr > 0;
 221 }
 222
 223 static int get_next_char(void)
 224 {
 225         int c = cf->do_fgetc(cf);
 226
 227         if (c == '\r') {
 228                 /* DOS like systems */
 229                 c = cf->do_fgetc(cf);
 230                 if (c != '\n') {
 231                         cf->do_ungetc(c, cf);
 232                         c = '\r';
 233                 }
 234         }
 235         if (c == '\n')
 236                 cf->linenr++;
 237         if (c == EOF) {
 238                 cf->eof = 1;
 239                 c = '\n';
 240         }
 241         return c;
 242 }
 243
 244 static char *parse_value(void)
 245 {
 246         int quote = 0, comment = 0, space = 0;
 247
 248         strbuf_reset(&cf->value);
 249         for (;;) {
 250                 int c = get_next_char();
 251                 if (c == '\n') {
 252                         if (quote) {
 253                                 cf->linenr--;
 254                                 return NULL;
 255                         }
 256                         return cf->value.buf;
 257                 }
 258                 if (comment)
 259                         continue;
 260                 if (isspace(c) && !quote) {
 261                         if (cf->value.len)
 262                                 space++;
 263                         continue;
 264                 }
 265                 if (!quote) {
 266                         if (c == ';' || c == '#') {
 267                                 comment = 1;
 268                                 continue;
 269                         }
 270                 }
 271                 for (; space; space--)
 272                         strbuf_addch(&cf->value, ' ');
 273                 if (c == '\\') {
 274                         c = get_next_char();
 275                         switch (c) {
 276                         case '\n':
 277                                 continue;
 278                         case 't':
 279                                 c = '\t';
 280                                 break;
 281                         case 'b':
 282                                 c = '\b';
 283                                 break;
 284                         case 'n':
 285                                 c = '\n';
 286                                 break;
 287                         /* Some characters escape as themselves */
 288                         case '\\': case '"':
 289                                 break;
 290                         /* Reject unknown escape sequences */
 291                         default:
 292                                 return NULL;
 293                         }
 294                         strbuf_addch(&cf->value, c);
 295                         continue;
 296                 }
 297                 if (c == '"') {
 298                         quote = 1-quote;
 299                         continue;
 300                 }
 301                 strbuf_addch(&cf->value, c);
 302         }
 303 }
 304
 305 static inline int iskeychar(int c)
 306 {
 307         return isalnum(c) || c == '-';
 308 }
 309
 310 static int get_value(config_fn_t fn, void *data, struct strbuf *name)
 311 {
 312         int c;
 313         char *value;
 314
 315         /* Get the full name */
 316         for (;;) {
 317                 c = get_next_char();
 318                 if (cf->eof)
 319                         break;
 320                 if (!iskeychar(c))
 321                         break;
 322                 strbuf_addch(name, tolower(c));
 323         }
 324
 325         while (c == ' ' || c == '\t')
 326                 c = get_next_char();
 327
 328         value = NULL;
 329         if (c != '\n') {
 330                 if (c != '=')
 331                         return -1;
 332                 value = parse_value();
 333                 if (!value)
 334                         return -1;
 335         }
 336         return fn(name->buf, value, data);
 337 }
 338
 339 static int get_extended_base_var(struct strbuf *name, int c)
 340 {
 341         do {
 342                 if (c == '\n')
 343                         goto error_incomplete_line;
 344                 c = get_next_char();
 345         } while (isspace(c));
 346
 347         /* We require the format to be '[base "extension"]' */
 348         if (c != '"')
 349                 return -1;
 350         strbuf_addch(name, '.');
 351
 352         for (;;) {
 353                 int c = get_next_char();
 354                 if (c == '\n')
 355                         goto error_incomplete_line;
 356                 if (c == '"')
 357                         break;
 358                 if (c == '\\') {
 359                         c = get_next_char();
 360                         if (c == '\n')
 361                                 goto error_incomplete_line;
 362                 }
 363                 strbuf_addch(name, c);
 364         }
 365
 366         /* Final ']' */
 367         if (get_next_char() != ']')
 368                 return -1;
 369         return 0;
 370 error_incomplete_line:
 371         cf->linenr--;
 372         return -1;
 373 }
 374
 375 static int get_base_var(struct strbuf *name)
 376 {
 377         for (;;) {
 378                 int c = get_next_char();
 379                 if (cf->eof)
 380                         return -1;
 381                 if (c == ']')
 382                         return 0;
 383                 if (isspace(c))
 384                         return get_extended_base_var(name, c);
 385                 if (!iskeychar(c) && c != '.')
 386                         return -1;
 387                 strbuf_addch(name, tolower(c));
 388         }
 389 }
 390
 391 static int git_parse_source(config_fn_t fn, void *data)
 392 {
 393         int comment = 0;
 394         int baselen = 0;
 395         struct strbuf *var = &cf->var;
 396
 397         /* U+FEFF Byte Order Mark in UTF8 */
 398         static const unsigned char *utf8_bom = (unsigned char *) "\xef\xbb\xbf";
 399         const unsigned char *bomptr = utf8_bom;
 400
 401         for (;;) {
 402                 int c = get_next_char();
 403                 if (bomptr && *bomptr) {
 404                         /* We are at the file beginning; skip UTF8-encoded BOM
 405                          * if present. Sane editors won't put this in on their
 406                          * own, but e.g. Windows Notepad will do it happily. */
 407                         if ((unsigned char) c == *bomptr) {
 408                                 bomptr++;
 409                                 continue;
 410                         } else {
 411                                 /* Do not tolerate partial BOM. */
 412                                 if (bomptr != utf8_bom)
 413                                         break;
 414                                 /* No BOM at file beginning. Cool. */
 415                                 bomptr = NULL;
 416                         }
 417                 }
 418                 if (c == '\n') {
 419                         if (cf->eof)
 420                                 return 0;
 421                         comment = 0;
 422                         continue;
 423                 }
 424                 if (comment || isspace(c))
 425                         continue;
 426                 if (c == '#' || c == ';') {
 427                         comment = 1;
 428                         continue;
 429                 }
 430                 if (c == '[') {
 431                         /* Reset prior to determining a new stem */
 432                         strbuf_reset(var);
 433                         if (get_base_var(var) < 0 || var->len < 1)
 434                                 break;
 435                         strbuf_addch(var, '.');
 436                         baselen = var->len;
 437                         continue;
 438                 }
 439                 if (!isalpha(c))
 440                         break;
 441                 /*
 442                  * Truncate the var name back to the section header
 443                  * stem prior to grabbing the suffix part of the name
 444                  * and the value.
 445                  */
 446                 strbuf_setlen(var, baselen);
 447                 strbuf_addch(var, tolower(c));
 448                 if (get_value(fn, data, var) < 0)
 449                         break;
 450         }
 451         if (cf->die_on_error)
 452                 die("bad config file line %d in %s", cf->linenr, cf->name);
 453         else
 454                 return error("bad config file line %d in %s", cf->linenr, cf->name);
 455 }
 456
 457 static int parse_unit_factor(const char *end, uintmax_t *val)
 458 {
 459         if (!*end)
 460                 return 1;
 461         else if (!strcasecmp(end, "k")) {
 462                 *val *= 1024;
 463                 return 1;
 464         }
 465         else if (!strcasecmp(end, "m")) {
 466                 *val *= 1024 * 1024;
 467                 return 1;
 468         }
 469         else if (!strcasecmp(end, "g")) {
 470                 *val *= 1024 * 1024 * 1024;
 471                 return 1;
 472         }
 473         return 0;
 474 }
 475
 476 static int git_parse_signed(const char *value, intmax_t *ret, intmax_t max)
 477 {
 478         if (value && *value) {
 479                 char *end;
 480                 intmax_t val;
 481                 uintmax_t uval;
 482                 uintmax_t factor = 1;
 483
 484                 errno = 0;
 485                 val = strtoimax(value, &end, 0);
 486                 if (errno == ERANGE)
 487                         return 0;
 488                 if (!parse_unit_factor(end, &factor)) {
 489                         errno = EINVAL;
 490                         return 0;
 491                 }
 492                 uval = abs(val);
 493                 uval *= factor;
 494                 if (uval > max || abs(val) > uval) {
 495                         errno = ERANGE;
 496                         return 0;
 497                 }
 498                 val *= factor;
 499                 *ret = val;
 500                 return 1;
 501         }
 502         errno = EINVAL;
 503         return 0;
 504 }
 505
 506 static int git_parse_unsigned(const char *value, uintmax_t *ret, uintmax_t max)
 507 {
 508         if (value && *value) {
 509                 char *end;
 510                 uintmax_t val;
 511                 uintmax_t oldval;
 512
 513                 errno = 0;
 514                 val = strtoumax(value, &end, 0);
 515                 if (errno == ERANGE)
 516                         return 0;
 517                 oldval = val;
 518                 if (!parse_unit_factor(end, &val)) {
 519                         errno = EINVAL;
 520                         return 0;
 521                 }
 522                 if (val > max || oldval > val) {
 523                         errno = ERANGE;
 524                         return 0;
 525                 }
 526                 *ret = val;
 527                 return 1;
 528         }
 529         errno = EINVAL;
 530         return 0;
 531 }
 532
 533 static int git_parse_int(const char *value, int *ret)
 534 {
 535         intmax_t tmp;
 536         if (!git_parse_signed(value, &tmp, maximum_signed_value_of_type(int)))
 537                 return 0;
 538         *ret = tmp;
 539         return 1;
 540 }
 541
 542 static int git_parse_int64(const char *value, int64_t *ret)
 543 {
 544         intmax_t tmp;
 545         if (!git_parse_signed(value, &tmp, maximum_signed_value_of_type(int64_t)))
 546                 return 0;
 547         *ret = tmp;
 548         return 1;
 549 }
 550
 551 int git_parse_ulong(const char *value, unsigned long *ret)
 552 {
 553         uintmax_t tmp;
 554         if (!git_parse_unsigned(value, &tmp, maximum_unsigned_value_of_type(long)))
 555                 return 0;
 556         *ret = tmp;
 557         return 1;
 558 }
 559
 560 static void die_bad_number(const char *name, const char *value)
 561 {
 562         const char *reason = errno == ERANGE ?
 563                              "out of range" :
 564                              "invalid unit";
 565         if (!value)
 566                 value = "";
 567
 568         if (cf && cf->name)
 569                 die("bad numeric config value '%s' for '%s' in %s: %s",
 570                     value, name, cf->name, reason);
 571         die("bad numeric config value '%s' for '%s': %s", value, name, reason);
 572 }
 573
 574 int git_config_int(const char *name, const char *value)
 575 {
 576         int ret;
 577         if (!git_parse_int(value, &ret))
 578                 die_bad_number(name, value);
 579         return ret;
 580 }
 581
 582 int64_t git_config_int64(const char *name, const char *value)
 583 {
 584         int64_t ret;
 585         if (!git_parse_int64(value, &ret))
 586                 die_bad_number(name, value);
 587         return ret;
 588 }
 589
 590 unsigned long git_config_ulong(const char *name, const char *value)
 591 {
 592         unsigned long ret;
 593         if (!git_parse_ulong(value, &ret))
 594                 die_bad_number(name, value);
 595         return ret;
 596 }
 597
 598 static int git_config_maybe_bool_text(const char *name, const char *value)
 599 {
 600         if (!value)
 601                 return 1;
 602         if (!*value)
 603                 return 0;
 604         if (!strcasecmp(value, "true")
 605             || !strcasecmp(value, "yes")
 606             || !strcasecmp(value, "on"))
 607                 return 1;
 608         if (!strcasecmp(value, "false")
 609             || !strcasecmp(value, "no")
 610             || !strcasecmp(value, "off"))
 611                 return 0;
 612         return -1;
 613 }
 614
 615 int git_config_maybe_bool(const char *name, const char *value)
 616 {
 617         int v = git_config_maybe_bool_text(name, value);
 618         if (0 <= v)
 619                 return v;
 620         if (git_parse_int(value, &v))
 621                 return !!v;
 622         return -1;
 623 }
 624
 625 int git_config_bool_or_int(const char *name, const char *value, int *is_bool)
 626 {
 627         int v = git_config_maybe_bool_text(name, value);
 628         if (0 <= v) {
 629                 *is_bool = 1;
 630                 return v;
 631         }
 632         *is_bool = 0;
 633         return git_config_int(name, value);
 634 }
 635
 636 int git_config_bool(const char *name, const char *value)
 637 {
 638         int discard;
 639         return !!git_config_bool_or_int(name, value, &discard);
 640 }
 641
 642 int git_config_string(const char **dest, const char *var, const char *value)
 643 {
 644         if (!value)
 645                 return config_error_nonbool(var);
 646         *dest = xstrdup(value);
 647         return 0;
 648 }
 649
 650 int git_config_pathname(const char **dest, const char *var, const char *value)
 651 {
 652         if (!value)
 653                 return config_error_nonbool(var);
 654         *dest = expand_user_path(value);
 655         if (!*dest)
 656                 die("Failed to expand user dir in: '%s'", value);
 657         return 0;
 658 }
 659
 660 static int git_default_core_config(const char *var, const char *value)
 661 {
 662         /* This needs a better name */
 663         if (!strcmp(var, "core.filemode")) {
 664                 trust_executable_bit = git_config_bool(var, value);
 665                 return 0;
 666         }
 667         if (!strcmp(var, "core.trustctime")) {
 668                 trust_ctime = git_config_bool(var, value);
 669                 return 0;
 670         }
 671         if (!strcmp(var, "core.checkstat")) {
 672                 if (!strcasecmp(value, "default"))
 673                         check_stat = 1;
 674                 else if (!strcasecmp(value, "minimal"))
 675                         check_stat = 0;
 676         }
 677
 678         if (!strcmp(var, "core.quotepath")) {
 679                 quote_path_fully = git_config_bool(var, value);
 680                 return 0;
 681         }
 682
 683         if (!strcmp(var, "core.symlinks")) {
 684                 has_symlinks = git_config_bool(var, value);
 685                 return 0;
 686         }
 687
 688         if (!strcmp(var, "core.ignorecase")) {
 689                 ignore_case = git_config_bool(var, value);
 690                 return 0;
 691         }
 692
 693         if (!strcmp(var, "core.attributesfile"))
 694                 return git_config_pathname(&git_attributes_file, var, value);
 695
 696         if (!strcmp(var, "core.bare")) {
 697                 is_bare_repository_cfg = git_config_bool(var, value);
 698                 return 0;
 699         }
 700
 701         if (!strcmp(var, "core.ignorestat")) {
 702                 assume_unchanged = git_config_bool(var, value);
 703                 return 0;
 704         }
 705
 706         if (!strcmp(var, "core.prefersymlinkrefs")) {
 707                 prefer_symlink_refs = git_config_bool(var, value);
 708                 return 0;
 709         }
 710
 711         if (!strcmp(var, "core.logallrefupdates")) {
 712                 log_all_ref_updates = git_config_bool(var, value);
 713                 return 0;
 714         }
 715
 716         if (!strcmp(var, "core.warnambiguousrefs")) {
 717                 warn_ambiguous_refs = git_config_bool(var, value);
 718                 return 0;
 719         }
 720
 721         if (!strcmp(var, "core.abbrev")) {
 722                 int abbrev = git_config_int(var, value);
 723                 if (abbrev < minimum_abbrev || abbrev > 40)
 724                         return -1;
 725                 default_abbrev = abbrev;
 726                 return 0;
 727         }
 728
 729         if (!strcmp(var, "core.loosecompression")) {
 730                 int level = git_config_int(var, value);
 731                 if (level == -1)
 732                         level = Z_DEFAULT_COMPRESSION;
 733                 else if (level < 0 || level > Z_BEST_COMPRESSION)
 734                         die("bad zlib compression level %d", level);
 735                 zlib_compression_level = level;
 736                 zlib_compression_seen = 1;
 737                 return 0;
 738         }
 739
 740         if (!strcmp(var, "core.compression")) {
 741                 int level = git_config_int(var, value);
 742                 if (level == -1)
 743                         level = Z_DEFAULT_COMPRESSION;
 744                 else if (level < 0 || level > Z_BEST_COMPRESSION)
 745                         die("bad zlib compression level %d", level);
 746                 core_compression_level = level;
 747                 core_compression_seen = 1;
 748                 if (!zlib_compression_seen)
 749                         zlib_compression_level = level;
 750                 return 0;
 751         }
 752
 753         if (!strcmp(var, "core.packedgitwindowsize")) {
 754                 int pgsz_x2 = getpagesize() * 2;
 755                 packed_git_window_size = git_config_ulong(var, value);
 756
 757                 /* This value must be multiple of (pagesize * 2) */
 758                 packed_git_window_size /= pgsz_x2;
 759                 if (packed_git_window_size < 1)
 760                         packed_git_window_size = 1;
 761                 packed_git_window_size *= pgsz_x2;
 762                 return 0;
 763         }
 764
 765         if (!strcmp(var, "core.bigfilethreshold")) {
 766                 big_file_threshold = git_config_ulong(var, value);
 767                 return 0;
 768         }
 769
 770         if (!strcmp(var, "core.packedgitlimit")) {
 771                 packed_git_limit = git_config_ulong(var, value);
 772                 return 0;
 773         }
 774
 775         if (!strcmp(var, "core.deltabasecachelimit")) {
 776                 delta_base_cache_limit = git_config_ulong(var, value);
 777                 return 0;
 778         }
 779
 780         if (!strcmp(var, "core.autocrlf")) {
 781                 if (value && !strcasecmp(value, "input")) {
 782                         if (core_eol == EOL_CRLF)
 783                                 return error("core.autocrlf=input conflicts with core.eol=crlf");
 784                         auto_crlf = AUTO_CRLF_INPUT;
 785                         return 0;
 786                 }
 787                 auto_crlf = git_config_bool(var, value);
 788                 return 0;
 789         }
 790
 791         if (!strcmp(var, "core.safecrlf")) {
 792                 if (value && !strcasecmp(value, "warn")) {
 793                         safe_crlf = SAFE_CRLF_WARN;
 794                         return 0;
 795                 }
 796                 safe_crlf = git_config_bool(var, value);
 797                 return 0;
 798         }
 799
 800         if (!strcmp(var, "core.eol")) {
 801                 if (value && !strcasecmp(value, "lf"))
 802                         core_eol = EOL_LF;
 803                 else if (value && !strcasecmp(value, "crlf"))
 804                         core_eol = EOL_CRLF;
 805                 else if (value && !strcasecmp(value, "native"))
 806                         core_eol = EOL_NATIVE;
 807                 else
 808                         core_eol = EOL_UNSET;
 809                 if (core_eol == EOL_CRLF && auto_crlf == AUTO_CRLF_INPUT)
 810                         return error("core.autocrlf=input conflicts with core.eol=crlf");
 811                 return 0;
 812         }
 813
 814         if (!strcmp(var, "core.notesref")) {
 815                 notes_ref_name = xstrdup(value);
 816                 return 0;
 817         }
 818
 819         if (!strcmp(var, "core.pager"))
 820                 return git_config_string(&pager_program, var, value);
 821
 822         if (!strcmp(var, "core.editor"))
 823                 return git_config_string(&editor_program, var, value);
 824
 825         if (!strcmp(var, "core.commentchar")) {
 826                 const char *comment;
 827                 int ret = git_config_string(&comment, var, value);
 828                 if (!ret)
 829                         comment_line_char = comment[0];
 830                 return ret;
 831         }
 832
 833         if (!strcmp(var, "core.askpass"))
 834                 return git_config_string(&askpass_program, var, value);
 835
 836         if (!strcmp(var, "core.excludesfile"))
 837                 return git_config_pathname(&excludes_file, var, value);
 838
 839         if (!strcmp(var, "core.whitespace")) {
 840                 if (!value)
 841                         return config_error_nonbool(var);
 842                 whitespace_rule_cfg = parse_whitespace_rule(value);
 843                 return 0;
 844         }
 845
 846         if (!strcmp(var, "core.fsyncobjectfiles")) {
 847                 fsync_object_files = git_config_bool(var, value);
 848                 return 0;
 849         }
 850
 851         if (!strcmp(var, "core.preloadindex")) {
 852                 core_preload_index = git_config_bool(var, value);
 853                 return 0;
 854         }
 855
 856         if (!strcmp(var, "core.createobject")) {
 857                 if (!strcmp(value, "rename"))
 858                         object_creation_mode = OBJECT_CREATION_USES_RENAMES;
 859                 else if (!strcmp(value, "link"))
 860                         object_creation_mode = OBJECT_CREATION_USES_HARDLINKS;
 861                 else
 862                         die("Invalid mode for object creation: %s", value);
 863                 return 0;
 864         }
 865
 866         if (!strcmp(var, "core.sparsecheckout")) {
 867                 core_apply_sparse_checkout = git_config_bool(var, value);
 868                 return 0;
 869         }
 870
 871         if (!strcmp(var, "core.precomposeunicode")) {
 872                 precomposed_unicode = git_config_bool(var, value);
 873                 return 0;
 874         }
 875
 876         /* Add other config variables here and to Documentation/config.txt. */
 877         return 0;
 878 }
 879
 880 static int git_default_i18n_config(const char *var, const char *value)
 881 {
 882         if (!strcmp(var, "i18n.commitencoding"))
 883                 return git_config_string(&git_commit_encoding, var, value);
 884
 885         if (!strcmp(var, "i18n.logoutputencoding"))
 886                 return git_config_string(&git_log_output_encoding, var, value);
 887
 888         /* Add other config variables here and to Documentation/config.txt. */
 889         return 0;
 890 }
 891
 892 static int git_default_branch_config(const char *var, const char *value)
 893 {
 894         if (!strcmp(var, "branch.autosetupmerge")) {
 895                 if (value && !strcasecmp(value, "always")) {
 896                         git_branch_track = BRANCH_TRACK_ALWAYS;
 897                         return 0;
 898                 }
 899                 git_branch_track = git_config_bool(var, value);
 900                 return 0;
 901         }
 902         if (!strcmp(var, "branch.autosetuprebase")) {
 903                 if (!value)
 904                         return config_error_nonbool(var);
 905                 else if (!strcmp(value, "never"))
 906                         autorebase = AUTOREBASE_NEVER;
 907                 else if (!strcmp(value, "local"))
 908                         autorebase = AUTOREBASE_LOCAL;
 909                 else if (!strcmp(value, "remote"))
 910                         autorebase = AUTOREBASE_REMOTE;
 911                 else if (!strcmp(value, "always"))
 912                         autorebase = AUTOREBASE_ALWAYS;
 913                 else
 914                         return error("Malformed value for %s", var);
 915                 return 0;
 916         }
 917
 918         /* Add other config variables here and to Documentation/config.txt. */
 919         return 0;
 920 }
 921
 922 static int git_default_push_config(const char *var, const char *value)
 923 {
 924         if (!strcmp(var, "push.default")) {
 925                 if (!value)
 926                         return config_error_nonbool(var);
 927                 else if (!strcmp(value, "nothing"))
 928                         push_default = PUSH_DEFAULT_NOTHING;
 929                 else if (!strcmp(value, "matching"))
 930                         push_default = PUSH_DEFAULT_MATCHING;
 931                 else if (!strcmp(value, "simple"))
 932                         push_default = PUSH_DEFAULT_SIMPLE;
 933                 else if (!strcmp(value, "upstream"))
 934                         push_default = PUSH_DEFAULT_UPSTREAM;
 935                 else if (!strcmp(value, "tracking")) /* deprecated */
 936                         push_default = PUSH_DEFAULT_UPSTREAM;
 937                 else if (!strcmp(value, "current"))
 938                         push_default = PUSH_DEFAULT_CURRENT;
 939                 else {
 940                         error("Malformed value for %s: %s", var, value);
 941                         return error("Must be one of nothing, matching, simple, "
 942                                      "upstream or current.");
 943                 }
 944                 return 0;
 945         }
 946
 947         /* Add other config variables here and to Documentation/config.txt. */
 948         return 0;
 949 }
 950
 951 static int git_default_mailmap_config(const char *var, const char *value)
 952 {
 953         if (!strcmp(var, "mailmap.file"))
 954                 return git_config_string(&git_mailmap_file, var, value);
 955         if (!strcmp(var, "mailmap.blob"))
 956                 return git_config_string(&git_mailmap_blob, var, value);
 957
 958         /* Add other config variables here and to Documentation/config.txt. */
 959         return 0;
 960 }
 961
 962 int git_default_config(const char *var, const char *value, void *dummy)
 963 {
 964         if (starts_with(var, "core."))
 965                 return git_default_core_config(var, value);
 966
 967         if (starts_with(var, "user."))
 968                 return git_ident_config(var, value, dummy);
 969
 970         if (starts_with(var, "i18n."))
 971                 return git_default_i18n_config(var, value);
 972
 973         if (starts_with(var, "branch."))
 974                 return git_default_branch_config(var, value);
 975
 976         if (starts_with(var, "push."))
 977                 return git_default_push_config(var, value);
 978
 979         if (starts_with(var, "mailmap."))
 980                 return git_default_mailmap_config(var, value);
 981
 982         if (starts_with(var, "advice."))
 983                 return git_default_advice_config(var, value);
 984
 985         if (!strcmp(var, "pager.color") || !strcmp(var, "color.pager")) {
 986                 pager_use_color = git_config_bool(var,value);
 987                 return 0;
 988         }
 989
 990         if (!strcmp(var, "pack.packsizelimit")) {
 991                 pack_size_limit_cfg = git_config_ulong(var, value);
 992                 return 0;
 993         }
 994         /* Add other config variables here and to Documentation/config.txt. */
 995         return 0;
 996 }
 997
 998 /*
 999  * All source specific fields in the union, die_on_error, name and the callbacks
1000  * fgetc, ungetc, ftell of top need to be initialized before calling
1001  * this function.
1002  */
1003 static int do_config_from(struct config_source *top, config_fn_t fn, void *data)
1004 {
1005         int ret;
1006
1007         /* push config-file parsing state stack */
1008         top->prev = cf;
1009         top->linenr = 1;
1010         top->eof = 0;
1011         strbuf_init(&top->value, 1024);
1012         strbuf_init(&top->var, 1024);
1013         cf = top;
1014
1015         ret = git_parse_source(fn, data);
1016
1017         /* pop config-file parsing state stack */
1018         strbuf_release(&top->value);
1019         strbuf_release(&top->var);
1020         cf = top->prev;
1021
1022         return ret;
1023 }
1024
1025 static int do_config_from_file(config_fn_t fn,
1026                 const char *name, const char *path, FILE *f, void *data)
1027 {
1028         struct config_source top;
1029
1030         top.u.file = f;
1031         top.name = name;
1032         top.path = path;
1033         top.die_on_error = 1;
1034         top.do_fgetc = config_file_fgetc;
1035         top.do_ungetc = config_file_ungetc;
1036         top.do_ftell = config_file_ftell;
1037
1038         return do_config_from(&top, fn, data);
1039 }
1040
1041 static int git_config_from_stdin(config_fn_t fn, void *data)
1042 {
1043         return do_config_from_file(fn, "<stdin>", NULL, stdin, data);
1044 }
1045
1046 int git_config_from_file(config_fn_t fn, const char *filename, void *data)
1047 {
1048         int ret = -1;
1049         FILE *f;
1050
1051         f = fopen(filename, "r");
1052         if (f) {
1053                 ret = do_config_from_file(fn, filename, filename, f, data);
1054                 fclose(f);
1055         }
1056         return ret;
1057 }
1058
1059 int git_config_from_buf(config_fn_t fn, const char *name, const char *buf,
1060                         size_t len, void *data)
1061 {
1062         struct config_source top;
1063
1064         top.u.buf.buf = buf;
1065         top.u.buf.len = len;
1066         top.u.buf.pos = 0;
1067         top.name = name;
1068         top.path = NULL;
1069         top.die_on_error = 0;
1070         top.do_fgetc = config_buf_fgetc;
1071         top.do_ungetc = config_buf_ungetc;
1072         top.do_ftell = config_buf_ftell;
1073
1074         return do_config_from(&top, fn, data);
1075 }
1076
1077 static int git_config_from_blob_sha1(config_fn_t fn,
1078                                      const char *name,
1079                                      const unsigned char *sha1,
1080                                      void *data)
1081 {
1082         enum object_type type;
1083         char *buf;
1084         unsigned long size;
1085         int ret;
1086
1087         buf = read_sha1_file(sha1, &type, &size);
1088         if (!buf)
1089                 return error("unable to load config blob object '%s'", name);
1090         if (type != OBJ_BLOB) {
1091                 free(buf);
1092                 return error("reference '%s' does not point to a blob", name);
1093         }
1094
1095         ret = git_config_from_buf(fn, name, buf, size, data);
1096         free(buf);
1097
1098         return ret;
1099 }
1100
1101 static int git_config_from_blob_ref(config_fn_t fn,
1102                                     const char *name,
1103                                     void *data)
1104 {
1105         unsigned char sha1[20];
1106
1107         if (get_sha1(name, sha1) < 0)
1108                 return error("unable to resolve config blob '%s'", name);
1109         return git_config_from_blob_sha1(fn, name, sha1, data);
1110 }
1111
1112 const char *git_etc_gitconfig(void)
1113 {
1114         static const char *system_wide;
1115         if (!system_wide)
1116                 system_wide = system_path(ETC_GITCONFIG);
1117         return system_wide;
1118 }
1119
1120 int git_env_bool(const char *k, int def)
1121 {
1122         const char *v = getenv(k);
1123         return v ? git_config_bool(k, v) : def;
1124 }
1125
1126 int git_config_system(void)
1127 {
1128         return !git_env_bool("GIT_CONFIG_NOSYSTEM", 0);
1129 }
1130
1131 int git_config_early(config_fn_t fn, void *data, const char *repo_config)
1132 {
1133         int ret = 0, found = 0;
1134         char *xdg_config = NULL;
1135         char *user_config = NULL;
1136
1137         home_config_paths(&user_config, &xdg_config, "config");
1138
1139         if (git_config_system() && !access_or_die(git_etc_gitconfig(), R_OK, 0)) {
1140                 ret += git_config_from_file(fn, git_etc_gitconfig(),
1141                                             data);
1142                 found += 1;
1143         }
1144
1145         if (xdg_config && !access_or_die(xdg_config, R_OK, ACCESS_EACCES_OK)) {
1146                 ret += git_config_from_file(fn, xdg_config, data);
1147                 found += 1;
1148         }
1149
1150         if (user_config && !access_or_die(user_config, R_OK, ACCESS_EACCES_OK)) {
1151                 ret += git_config_from_file(fn, user_config, data);
1152                 found += 1;
1153         }
1154
1155         if (repo_config && !access_or_die(repo_config, R_OK, 0)) {
1156                 ret += git_config_from_file(fn, repo_config, data);
1157                 found += 1;
1158         }
1159
1160         switch (git_config_from_parameters(fn, data)) {
1161         case -1: /* error */
1162                 die("unable to parse command-line config");
1163                 break;
1164         case 0: /* found nothing */
1165                 break;
1166         default: /* found at least one item */
1167                 found++;
1168                 break;
1169         }
1170
1171         free(xdg_config);
1172         free(user_config);
1173         return ret == 0 ? found : ret;
1174 }
1175
1176 int git_config_with_options(config_fn_t fn, void *data,
1177                             struct git_config_source *config_source,
1178                             int respect_includes)
1179 {
1180         char *repo_config = NULL;
1181         int ret;
1182         struct config_include_data inc = CONFIG_INCLUDE_INIT;
1183
1184         if (respect_includes) {
1185                 inc.fn = fn;
1186                 inc.data = data;
1187                 fn = git_config_include;
1188                 data = &inc;
1189         }
1190
1191         /*
1192          * If we have a specific filename, use it. Otherwise, follow the
1193          * regular lookup sequence.
1194          */
1195         if (config_source && config_source->use_stdin)
1196                 return git_config_from_stdin(fn, data);
1197         else if (config_source && config_source->file)
1198                 return git_config_from_file(fn, config_source->file, data);
1199         else if (config_source && config_source->blob)
1200                 return git_config_from_blob_ref(fn, config_source->blob, data);
1201
1202         repo_config = git_pathdup("config");
1203         ret = git_config_early(fn, data, repo_config);
1204         if (repo_config)
1205                 free(repo_config);
1206         return ret;
1207 }
1208
1209 int git_config(config_fn_t fn, void *data)
1210 {
1211         return git_config_with_options(fn, data, NULL, 1);
1212 }
1213
1214 /*
1215  * Find all the stuff for git_config_set() below.
1216  */
1217
1218 static struct {
1219         int baselen;
1220         char *key;
1221         int do_not_match;
1222         regex_t *value_regex;
1223         int multi_replace;
1224         size_t *offset;
1225         unsigned int offset_alloc;
1226         enum { START, SECTION_SEEN, SECTION_END_SEEN, KEY_SEEN } state;
1227         int seen;
1228 } store;
1229
1230 static int matches(const char *key, const char *value)
1231 {
1232         return !strcmp(key, store.key) &&
1233                 (store.value_regex == NULL ||
1234                  (store.do_not_match ^
1235                   !regexec(store.value_regex, value, 0, NULL, 0)));
1236 }
1237
1238 static int store_aux(const char *key, const char *value, void *cb)
1239 {
1240         const char *ep;
1241         size_t section_len;
1242
1243         switch (store.state) {
1244         case KEY_SEEN:
1245                 if (matches(key, value)) {
1246                         if (store.seen == 1 && store.multi_replace == 0) {
1247                                 warning("%s has multiple values", key);
1248                         }
1249
1250                         ALLOC_GROW(store.offset, store.seen + 1,
1251                                    store.offset_alloc);
1252
1253                         store.offset[store.seen] = cf->do_ftell(cf);
1254                         store.seen++;
1255                 }
1256                 break;
1257         case SECTION_SEEN:
1258                 /*
1259                  * What we are looking for is in store.key (both
1260                  * section and var), and its section part is baselen
1261                  * long.  We found key (again, both section and var).
1262                  * We would want to know if this key is in the same
1263                  * section as what we are looking for.  We already
1264                  * know we are in the same section as what should
1265                  * hold store.key.
1266                  */
1267                 ep = strrchr(key, '.');
1268                 section_len = ep - key;
1269
1270                 if ((section_len != store.baselen) ||
1271                     memcmp(key, store.key, section_len+1)) {
1272                         store.state = SECTION_END_SEEN;
1273                         break;
1274                 }
1275
1276                 /*
1277                  * Do not increment matches: this is no match, but we
1278                  * just made sure we are in the desired section.
1279                  */
1280                 ALLOC_GROW(store.offset, store.seen + 1,
1281                            store.offset_alloc);
1282                 store.offset[store.seen] = cf->do_ftell(cf);
1283                 /* fallthru */
1284         case SECTION_END_SEEN:
1285         case START:
1286                 if (matches(key, value)) {
1287                         ALLOC_GROW(store.offset, store.seen + 1,
1288                                    store.offset_alloc);
1289                         store.offset[store.seen] = cf->do_ftell(cf);
1290                         store.state = KEY_SEEN;
1291                         store.seen++;
1292                 } else {
1293                         if (strrchr(key, '.') - key == store.baselen &&
1294                               !strncmp(key, store.key, store.baselen)) {
1295                                         store.state = SECTION_SEEN;
1296                                         ALLOC_GROW(store.offset,
1297                                                    store.seen + 1,
1298                                                    store.offset_alloc);
1299                                         store.offset[store.seen] = cf->do_ftell(cf);
1300                         }
1301                 }
1302         }
1303         return 0;
1304 }
1305
1306 static int write_error(const char *filename)
1307 {
1308         error("failed to write new configuration file %s", filename);
1309
1310         /* Same error code as "failed to rename". */
1311         return 4;
1312 }
1313
1314 static int store_write_section(int fd, const char *key)
1315 {
1316         const char *dot;
1317         int i, success;
1318         struct strbuf sb = STRBUF_INIT;
1319
1320         dot = memchr(key, '.', store.baselen);
1321         if (dot) {
1322                 strbuf_addf(&sb, "[%.*s \"", (int)(dot - key), key);
1323                 for (i = dot - key + 1; i < store.baselen; i++) {
1324                         if (key[i] == '"' || key[i] == '\\')
1325                                 strbuf_addch(&sb, '\\');
1326                         strbuf_addch(&sb, key[i]);
1327                 }
1328                 strbuf_addstr(&sb, "\"]\n");
1329         } else {
1330                 strbuf_addf(&sb, "[%.*s]\n", store.baselen, key);
1331         }
1332
1333         success = write_in_full(fd, sb.buf, sb.len) == sb.len;
1334         strbuf_release(&sb);
1335
1336         return success;
1337 }
1338
1339 static int store_write_pair(int fd, const char *key, const char *value)
1340 {
1341         int i, success;
1342         int length = strlen(key + store.baselen + 1);
1343         const char *quote = "";
1344         struct strbuf sb = STRBUF_INIT;
1345
1346         /*
1347          * Check to see if the value needs to be surrounded with a dq pair.
1348          * Note that problematic characters are always backslash-quoted; this
1349          * check is about not losing leading or trailing SP and strings that
1350          * follow beginning-of-comment characters (i.e. ';' and '#') by the
1351          * configuration parser.
1352          */
1353         if (value[0] == ' ')
1354                 quote = "\"";
1355         for (i = 0; value[i]; i++)
1356                 if (value[i] == ';' || value[i] == '#')
1357                         quote = "\"";
1358         if (i && value[i - 1] == ' ')
1359                 quote = "\"";
1360
1361         strbuf_addf(&sb, "\t%.*s = %s",
1362                     length, key + store.baselen + 1, quote);
1363
1364         for (i = 0; value[i]; i++)
1365                 switch (value[i]) {
1366                 case '\n':
1367                         strbuf_addstr(&sb, "\\n");
1368                         break;
1369                 case '\t':
1370                         strbuf_addstr(&sb, "\\t");
1371                         break;
1372                 case '"':
1373                 case '\\':
1374                         strbuf_addch(&sb, '\\');
1375                 default:
1376                         strbuf_addch(&sb, value[i]);
1377                         break;
1378                 }
1379         strbuf_addf(&sb, "%s\n", quote);
1380
1381         success = write_in_full(fd, sb.buf, sb.len) == sb.len;
1382         strbuf_release(&sb);
1383
1384         return success;
1385 }
1386
1387 static ssize_t find_beginning_of_line(const char *contents, size_t size,
1388         size_t offset_, int *found_bracket)
1389 {
1390         size_t equal_offset = size, bracket_offset = size;
1391         ssize_t offset;
1392
1393 contline:
1394         for (offset = offset_-2; offset > 0
1395                         && contents[offset] != '\n'; offset--)
1396                 switch (contents[offset]) {
1397                         case '=': equal_offset = offset; break;
1398                         case ']': bracket_offset = offset; break;
1399                 }
1400         if (offset > 0 && contents[offset-1] == '\\') {
1401                 offset_ = offset;
1402                 goto contline;
1403         }
1404         if (bracket_offset < equal_offset) {
1405                 *found_bracket = 1;
1406                 offset = bracket_offset+1;
1407         } else
1408                 offset++;
1409
1410         return offset;
1411 }
1412
1413 int git_config_set_in_file(const char *config_filename,
1414                         const char *key, const char *value)
1415 {
1416         return git_config_set_multivar_in_file(config_filename, key, value, NULL, 0);
1417 }
1418
1419 int git_config_set(const char *key, const char *value)
1420 {
1421         return git_config_set_multivar(key, value, NULL, 0);
1422 }
1423
1424 /*
1425  * Auxiliary function to sanity-check and split the key into the section
1426  * identifier and variable name.
1427  *
1428  * Returns 0 on success, -1 when there is an invalid character in the key and
1429  * -2 if there is no section name in the key.
1430  *
1431  * store_key - pointer to char* which will hold a copy of the key with
1432  *             lowercase section and variable name
1433  * baselen - pointer to int which will hold the length of the
1434  *           section + subsection part, can be NULL
1435  */
1436 int git_config_parse_key(const char *key, char **store_key, int *baselen_)
1437 {
1438         int i, dot, baselen;
1439         const char *last_dot = strrchr(key, '.');
1440
1441         /*
1442          * Since "key" actually contains the section name and the real
1443          * key name separated by a dot, we have to know where the dot is.
1444          */
1445
1446         if (last_dot == NULL || last_dot == key) {
1447                 error("key does not contain a section: %s", key);
1448                 return -CONFIG_NO_SECTION_OR_NAME;
1449         }
1450
1451         if (!last_dot[1]) {
1452                 error("key does not contain variable name: %s", key);
1453                 return -CONFIG_NO_SECTION_OR_NAME;
1454         }
1455
1456         baselen = last_dot - key;
1457         if (baselen_)
1458                 *baselen_ = baselen;
1459
1460         /*
1461          * Validate the key and while at it, lower case it for matching.
1462          */
1463         *store_key = xmalloc(strlen(key) + 1);
1464
1465         dot = 0;
1466         for (i = 0; key[i]; i++) {
1467                 unsigned char c = key[i];
1468                 if (c == '.')
1469                         dot = 1;
1470                 /* Leave the extended basename untouched.. */
1471                 if (!dot || i > baselen) {
1472                         if (!iskeychar(c) ||
1473                             (i == baselen + 1 && !isalpha(c))) {
1474                                 error("invalid key: %s", key);
1475                                 goto out_free_ret_1;
1476                         }
1477                         c = tolower(c);
1478                 } else if (c == '\n') {
1479                         error("invalid key (newline): %s", key);
1480                         goto out_free_ret_1;
1481                 }
1482                 (*store_key)[i] = c;
1483         }
1484         (*store_key)[i] = 0;
1485
1486         return 0;
1487
1488 out_free_ret_1:
1489         free(*store_key);
1490         *store_key = NULL;
1491         return -CONFIG_INVALID_KEY;
1492 }
1493
1494 /*
1495  * If value==NULL, unset in (remove from) config,
1496  * if value_regex!=NULL, disregard key/value pairs where value does not match.
1497  * if multi_replace==0, nothing, or only one matching key/value is replaced,
1498  *     else all matching key/values (regardless how many) are removed,
1499  *     before the new pair is written.
1500  *
1501  * Returns 0 on success.
1502  *
1503  * This function does this:
1504  *
1505  * - it locks the config file by creating ".git/config.lock"
1506  *
1507  * - it then parses the config using store_aux() as validator to find
1508  *   the position on the key/value pair to replace. If it is to be unset,
1509  *   it must be found exactly once.
1510  *
1511  * - the config file is mmap()ed and the part before the match (if any) is
1512  *   written to the lock file, then the changed part and the rest.
1513  *
1514  * - the config file is removed and the lock file rename()d to it.
1515  *
1516  */
1517 int git_config_set_multivar_in_file(const char *config_filename,
1518                                 const char *key, const char *value,
1519                                 const char *value_regex, int multi_replace)
1520 {
1521         int fd = -1, in_fd;
1522         int ret;
1523         struct lock_file *lock = NULL;
1524         char *filename_buf = NULL;
1525
1526         /* parse-key returns negative; flip the sign to feed exit(3) */
1527         ret = 0 - git_config_parse_key(key, &store.key, &store.baselen);
1528         if (ret)
1529                 goto out_free;
1530
1531         store.multi_replace = multi_replace;
1532
1533         if (!config_filename)
1534                 config_filename = filename_buf = git_pathdup("config");
1535
1536         /*
1537          * The lock serves a purpose in addition to locking: the new
1538          * contents of .git/config will be written into it.
1539          */
1540         lock = xcalloc(sizeof(struct lock_file), 1);
1541         fd = hold_lock_file_for_update(lock, config_filename, 0);
1542         if (fd < 0) {
1543                 error("could not lock config file %s: %s", config_filename, strerror(errno));
1544                 free(store.key);
1545                 ret = CONFIG_NO_LOCK;
1546                 goto out_free;
1547         }
1548
1549         /*
1550          * If .git/config does not exist yet, write a minimal version.
1551          */
1552         in_fd = open(config_filename, O_RDONLY);
1553         if ( in_fd < 0 ) {
1554                 free(store.key);
1555
1556                 if ( ENOENT != errno ) {
1557                         error("opening %s: %s", config_filename,
1558                               strerror(errno));
1559                         ret = CONFIG_INVALID_FILE; /* same as "invalid config file" */
1560                         goto out_free;
1561                 }
1562                 /* if nothing to unset, error out */
1563                 if (value == NULL) {
1564                         ret = CONFIG_NOTHING_SET;
1565                         goto out_free;
1566                 }
1567
1568                 store.key = (char *)key;
1569                 if (!store_write_section(fd, key) ||
1570                     !store_write_pair(fd, key, value))
1571                         goto write_err_out;
1572         } else {
1573                 struct stat st;
1574                 char *contents;
1575                 size_t contents_sz, copy_begin, copy_end;
1576                 int i, new_line = 0;
1577
1578                 if (value_regex == NULL)
1579                         store.value_regex = NULL;
1580                 else {
1581                         if (value_regex[0] == '!') {
1582                                 store.do_not_match = 1;
1583                                 value_regex++;
1584                         } else
1585                                 store.do_not_match = 0;
1586
1587                         store.value_regex = (regex_t*)xmalloc(sizeof(regex_t));
1588                         if (regcomp(store.value_regex, value_regex,
1589                                         REG_EXTENDED)) {
1590                                 error("invalid pattern: %s", value_regex);
1591                                 free(store.value_regex);
1592                                 ret = CONFIG_INVALID_PATTERN;
1593                                 goto out_free;
1594                         }
1595                 }
1596
1597                 ALLOC_GROW(store.offset, 1, store.offset_alloc);
1598                 store.offset[0] = 0;
1599                 store.state = START;
1600                 store.seen = 0;
1601
1602                 /*
1603                  * After this, store.offset will contain the *end* offset
1604                  * of the last match, or remain at 0 if no match was found.
1605                  * As a side effect, we make sure to transform only a valid
1606                  * existing config file.
1607                  */
1608                 if (git_config_from_file(store_aux, config_filename, NULL)) {
1609                         error("invalid config file %s", config_filename);
1610                         free(store.key);
1611                         if (store.value_regex != NULL) {
1612                                 regfree(store.value_regex);
1613                                 free(store.value_regex);
1614                         }
1615                         ret = CONFIG_INVALID_FILE;
1616                         goto out_free;
1617                 }
1618
1619                 free(store.key);
1620                 if (store.value_regex != NULL) {
1621                         regfree(store.value_regex);
1622                         free(store.value_regex);
1623                 }
1624
1625                 /* if nothing to unset, or too many matches, error out */
1626                 if ((store.seen == 0 && value == NULL) ||
1627                                 (store.seen > 1 && multi_replace == 0)) {
1628                         ret = CONFIG_NOTHING_SET;
1629                         goto out_free;
1630                 }
1631
1632                 fstat(in_fd, &st);
1633                 contents_sz = xsize_t(st.st_size);
1634                 contents = xmmap(NULL, contents_sz, PROT_READ,
1635                         MAP_PRIVATE, in_fd, 0);
1636                 close(in_fd);
1637
1638                 if (store.seen == 0)
1639                         store.seen = 1;
1640
1641                 for (i = 0, copy_begin = 0; i < store.seen; i++) {
1642                         if (store.offset[i] == 0) {
1643                                 store.offset[i] = copy_end = contents_sz;
1644                         } else if (store.state != KEY_SEEN) {
1645                                 copy_end = store.offset[i];
1646                         } else
1647                                 copy_end = find_beginning_of_line(
1648                                         contents, contents_sz,
1649                                         store.offset[i]-2, &new_line);
1650
1651                         if (copy_end > 0 && contents[copy_end-1] != '\n')
1652                                 new_line = 1;
1653
1654                         /* write the first part of the config */
1655                         if (copy_end > copy_begin) {
1656                                 if (write_in_full(fd, contents + copy_begin,
1657                                                   copy_end - copy_begin) <
1658                                     copy_end - copy_begin)
1659                                         goto write_err_out;
1660                                 if (new_line &&
1661                                     write_str_in_full(fd, "\n") != 1)
1662                                         goto write_err_out;
1663                         }
1664                         copy_begin = store.offset[i];
1665                 }
1666
1667                 /* write the pair (value == NULL means unset) */
1668                 if (value != NULL) {
1669                         if (store.state == START) {
1670                                 if (!store_write_section(fd, key))
1671                                         goto write_err_out;
1672                         }
1673                         if (!store_write_pair(fd, key, value))
1674                                 goto write_err_out;
1675                 }
1676
1677                 /* write the rest of the config */
1678                 if (copy_begin < contents_sz)
1679                         if (write_in_full(fd, contents + copy_begin,
1680                                           contents_sz - copy_begin) <
1681                             contents_sz - copy_begin)
1682                                 goto write_err_out;
1683
1684                 munmap(contents, contents_sz);
1685         }
1686
1687         if (commit_lock_file(lock) < 0) {
1688                 error("could not commit config file %s", config_filename);
1689                 ret = CONFIG_NO_WRITE;
1690                 goto out_free;
1691         }
1692
1693         /*
1694          * lock is committed, so don't try to roll it back below.
1695          * NOTE: Since lockfile.c keeps a linked list of all created
1696          * lock_file structures, it isn't safe to free(lock).  It's
1697          * better to just leave it hanging around.
1698          */
1699         lock = NULL;
1700         ret = 0;
1701
1702 out_free:
1703         if (lock)
1704                 rollback_lock_file(lock);
1705         free(filename_buf);
1706         return ret;
1707
1708 write_err_out:
1709         ret = write_error(lock->filename);
1710         goto out_free;
1711
1712 }
1713
1714 int git_config_set_multivar(const char *key, const char *value,
1715                         const char *value_regex, int multi_replace)
1716 {
1717         return git_config_set_multivar_in_file(NULL, key, value, value_regex,
1718                                                multi_replace);
1719 }
1720
1721 static int section_name_match (const char *buf, const char *name)
1722 {
1723         int i = 0, j = 0, dot = 0;
1724         if (buf[i] != '[')
1725                 return 0;
1726         for (i = 1; buf[i] && buf[i] != ']'; i++) {
1727                 if (!dot && isspace(buf[i])) {
1728                         dot = 1;
1729                         if (name[j++] != '.')
1730                                 break;
1731                         for (i++; isspace(buf[i]); i++)
1732                                 ; /* do nothing */
1733                         if (buf[i] != '"')
1734                                 break;
1735                         continue;
1736                 }
1737                 if (buf[i] == '\\' && dot)
1738                         i++;
1739                 else if (buf[i] == '"' && dot) {
1740                         for (i++; isspace(buf[i]); i++)
1741                                 ; /* do_nothing */
1742                         break;
1743                 }
1744                 if (buf[i] != name[j++])
1745                         break;
1746         }
1747         if (buf[i] == ']' && name[j] == 0) {
1748                 /*
1749                  * We match, now just find the right length offset by
1750                  * gobbling up any whitespace after it, as well
1751                  */
1752                 i++;
1753                 for (; buf[i] && isspace(buf[i]); i++)
1754                         ; /* do nothing */
1755                 return i;
1756         }
1757         return 0;
1758 }
1759
1760 static int section_name_is_ok(const char *name)
1761 {
1762         /* Empty section names are bogus. */
1763         if (!*name)
1764                 return 0;
1765
1766         /*
1767          * Before a dot, we must be alphanumeric or dash. After the first dot,
1768          * anything goes, so we can stop checking.
1769          */
1770         for (; *name && *name != '.'; name++)
1771                 if (*name != '-' && !isalnum(*name))
1772                         return 0;
1773         return 1;
1774 }
1775
1776 /* if new_name == NULL, the section is removed instead */
1777 int git_config_rename_section_in_file(const char *config_filename,
1778                                       const char *old_name, const char *new_name)
1779 {
1780         int ret = 0, remove = 0;
1781         char *filename_buf = NULL;
1782         struct lock_file *lock;
1783         int out_fd;
1784         char buf[1024];
1785         FILE *config_file;
1786
1787         if (new_name && !section_name_is_ok(new_name)) {
1788                 ret = error("invalid section name: %s", new_name);
1789                 goto out;
1790         }
1791
1792         if (!config_filename)
1793                 config_filename = filename_buf = git_pathdup("config");
1794
1795         lock = xcalloc(sizeof(struct lock_file), 1);
1796         out_fd = hold_lock_file_for_update(lock, config_filename, 0);
1797         if (out_fd < 0) {
1798                 ret = error("could not lock config file %s", config_filename);
1799                 goto out;
1800         }
1801
1802         if (!(config_file = fopen(config_filename, "rb"))) {
1803                 /* no config file means nothing to rename, no error */
1804                 goto unlock_and_out;
1805         }
1806
1807         while (fgets(buf, sizeof(buf), config_file)) {
1808                 int i;
1809                 int length;
1810                 char *output = buf;
1811                 for (i = 0; buf[i] && isspace(buf[i]); i++)
1812                         ; /* do nothing */
1813                 if (buf[i] == '[') {
1814                         /* it's a section */
1815                         int offset = section_name_match(&buf[i], old_name);
1816                         if (offset > 0) {
1817                                 ret++;
1818                                 if (new_name == NULL) {
1819                                         remove = 1;
1820                                         continue;
1821                                 }
1822                                 store.baselen = strlen(new_name);
1823                                 if (!store_write_section(out_fd, new_name)) {
1824                                         ret = write_error(lock->filename);
1825                                         goto out;
1826                                 }
1827                                 /*
1828                                  * We wrote out the new section, with
1829                                  * a newline, now skip the old
1830                                  * section's length
1831                                  */
1832                                 output += offset + i;
1833                                 if (strlen(output) > 0) {
1834                                         /*
1835                                          * More content means there's
1836                                          * a declaration to put on the
1837                                          * next line; indent with a
1838                                          * tab
1839                                          */
1840                                         output -= 1;
1841                                         output[0] = '\t';
1842                                 }
1843                         }
1844                         remove = 0;
1845                 }
1846                 if (remove)
1847                         continue;
1848                 length = strlen(output);
1849                 if (write_in_full(out_fd, output, length) != length) {
1850                         ret = write_error(lock->filename);
1851                         goto out;
1852                 }
1853         }
1854         fclose(config_file);
1855 unlock_and_out:
1856         if (commit_lock_file(lock) < 0)
1857                 ret = error("could not commit config file %s", config_filename);
1858 out:
1859         free(filename_buf);
1860         return ret;
1861 }
1862
1863 int git_config_rename_section(const char *old_name, const char *new_name)
1864 {
1865         return git_config_rename_section_in_file(NULL, old_name, new_name);
1866 }
1867
1868 /*
1869  * Call this to report error for your variable that should not
1870  * get a boolean value (i.e. "[my] var" means "true").
1871  */
1872 #undef config_error_nonbool
1873 int config_error_nonbool(const char *var)
1874 {
1875         return error("Missing value for '%s'", var);
1876 }
1877
1878 int parse_config_key(const char *var,
1879                      const char *section,
1880                      const char **subsection, int *subsection_len,
1881                      const char **key)
1882 {
1883         int section_len = strlen(section);
1884         const char *dot;
1885
1886         /* Does it start with "section." ? */
1887         if (!starts_with(var, section) || var[section_len] != '.')
1888                 return -1;
1889
1890         /*
1891          * Find the key; we don't know yet if we have a subsection, but we must
1892          * parse backwards from the end, since the subsection may have dots in
1893          * it, too.
1894          */
1895         dot = strrchr(var, '.');
1896         *key = dot + 1;
1897
1898         /* Did we have a subsection at all? */
1899         if (dot == var + section_len) {
1900                 *subsection = NULL;
1901                 *subsection_len = 0;
1902         }
1903         else {
1904                 *subsection = var + section_len + 1;
1905                 *subsection_len = dot - *subsection;
1906         }
1907
1908         return 0;
1909 }