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 (*do_fgetc)(struct config_source *c);
  31         int (*do_ungetc)(int c, struct config_source *conf);
  32         long (*do_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->do_fgetc(cf);
 221
 222         if (c == '\r') {
 223                 /* DOS like systems */
 224                 c = cf->do_fgetc(cf);
 225                 if (c != '\n') {
 226                         cf->do_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_signed(const char *value, intmax_t *ret, intmax_t max)
 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                         errno = EINVAL;
 485                         return 0;
 486                 }
 487                 uval = abs(val);
 488                 uval *= factor;
 489                 if (uval > max || abs(val) > uval) {
 490                         errno = ERANGE;
 491                         return 0;
 492                 }
 493                 val *= factor;
 494                 *ret = val;
 495                 return 1;
 496         }
 497         errno = EINVAL;
 498         return 0;
 499 }
 500
 501 static int git_parse_unsigned(const char *value, uintmax_t *ret, uintmax_t max)
 502 {
 503         if (value && *value) {
 504                 char *end;
 505                 uintmax_t val;
 506                 uintmax_t oldval;
 507
 508                 errno = 0;
 509                 val = strtoumax(value, &end, 0);
 510                 if (errno == ERANGE)
 511                         return 0;
 512                 oldval = val;
 513                 if (!parse_unit_factor(end, &val)) {
 514                         errno = EINVAL;
 515                         return 0;
 516                 }
 517                 if (val > max || oldval > val) {
 518                         errno = ERANGE;
 519                         return 0;
 520                 }
 521                 *ret = val;
 522                 return 1;
 523         }
 524         errno = EINVAL;
 525         return 0;
 526 }
 527
 528 static int git_parse_int(const char *value, int *ret)
 529 {
 530         intmax_t tmp;
 531         if (!git_parse_signed(value, &tmp, maximum_signed_value_of_type(int)))
 532                 return 0;
 533         *ret = tmp;
 534         return 1;
 535 }
 536
 537 static int git_parse_int64(const char *value, int64_t *ret)
 538 {
 539         intmax_t tmp;
 540         if (!git_parse_signed(value, &tmp, maximum_signed_value_of_type(int64_t)))
 541                 return 0;
 542         *ret = tmp;
 543         return 1;
 544 }
 545
 546 int git_parse_ulong(const char *value, unsigned long *ret)
 547 {
 548         uintmax_t tmp;
 549         if (!git_parse_unsigned(value, &tmp, maximum_unsigned_value_of_type(long)))
 550                 return 0;
 551         *ret = tmp;
 552         return 1;
 553 }
 554
 555 static void die_bad_number(const char *name, const char *value)
 556 {
 557         const char *reason = errno == ERANGE ?
 558                              "out of range" :
 559                              "invalid unit";
 560         if (!value)
 561                 value = "";
 562
 563         if (cf && cf->name)
 564                 die("bad numeric config value '%s' for '%s' in %s: %s",
 565                     value, name, cf->name, reason);
 566         die("bad numeric config value '%s' for '%s': %s", value, name, reason);
 567 }
 568
 569 int git_config_int(const char *name, const char *value)
 570 {
 571         int ret;
 572         if (!git_parse_int(value, &ret))
 573                 die_bad_number(name, value);
 574         return ret;
 575 }
 576
 577 int64_t git_config_int64(const char *name, const char *value)
 578 {
 579         int64_t ret;
 580         if (!git_parse_int64(value, &ret))
 581                 die_bad_number(name, value);
 582         return ret;
 583 }
 584
 585 unsigned long git_config_ulong(const char *name, const char *value)
 586 {
 587         unsigned long ret;
 588         if (!git_parse_ulong(value, &ret))
 589                 die_bad_number(name, value);
 590         return ret;
 591 }
 592
 593 static int git_config_maybe_bool_text(const char *name, const char *value)
 594 {
 595         if (!value)
 596                 return 1;
 597         if (!*value)
 598                 return 0;
 599         if (!strcasecmp(value, "true")
 600             || !strcasecmp(value, "yes")
 601             || !strcasecmp(value, "on"))
 602                 return 1;
 603         if (!strcasecmp(value, "false")
 604             || !strcasecmp(value, "no")
 605             || !strcasecmp(value, "off"))
 606                 return 0;
 607         return -1;
 608 }
 609
 610 int git_config_maybe_bool(const char *name, const char *value)
 611 {
 612         int v = git_config_maybe_bool_text(name, value);
 613         if (0 <= v)
 614                 return v;
 615         if (git_parse_int(value, &v))
 616                 return !!v;
 617         return -1;
 618 }
 619
 620 int git_config_bool_or_int(const char *name, const char *value, int *is_bool)
 621 {
 622         int v = git_config_maybe_bool_text(name, value);
 623         if (0 <= v) {
 624                 *is_bool = 1;
 625                 return v;
 626         }
 627         *is_bool = 0;
 628         return git_config_int(name, value);
 629 }
 630
 631 int git_config_bool(const char *name, const char *value)
 632 {
 633         int discard;
 634         return !!git_config_bool_or_int(name, value, &discard);
 635 }
 636
 637 int git_config_string(const char **dest, const char *var, const char *value)
 638 {
 639         if (!value)
 640                 return config_error_nonbool(var);
 641         *dest = xstrdup(value);
 642         return 0;
 643 }
 644
 645 int git_config_pathname(const char **dest, const char *var, const char *value)
 646 {
 647         if (!value)
 648                 return config_error_nonbool(var);
 649         *dest = expand_user_path(value);
 650         if (!*dest)
 651                 die("Failed to expand user dir in: '%s'", value);
 652         return 0;
 653 }
 654
 655 static int git_default_core_config(const char *var, const char *value)
 656 {
 657         /* This needs a better name */
 658         if (!strcmp(var, "core.filemode")) {
 659                 trust_executable_bit = git_config_bool(var, value);
 660                 return 0;
 661         }
 662         if (!strcmp(var, "core.trustctime")) {
 663                 trust_ctime = git_config_bool(var, value);
 664                 return 0;
 665         }
 666         if (!strcmp(var, "core.statinfo") ||
 667             !strcmp(var, "core.checkstat")) {
 668                 /*
 669                  * NEEDSWORK: statinfo was a typo in v1.8.2 that has
 670                  * never been advertised.  we will remove it at Git
 671                  * 2.0 boundary.
 672                  */
 673                 if (!strcmp(var, "core.statinfo")) {
 674                         static int warned;
 675                         if (!warned++) {
 676                                 warning("'core.statinfo' will be removed in Git 2.0; "
 677                                         "use 'core.checkstat' instead.");
 678                         }
 679                 }
 680                 if (!strcasecmp(value, "default"))
 681                         check_stat = 1;
 682                 else if (!strcasecmp(value, "minimal"))
 683                         check_stat = 0;
 684         }
 685
 686         if (!strcmp(var, "core.quotepath")) {
 687                 quote_path_fully = git_config_bool(var, value);
 688                 return 0;
 689         }
 690
 691         if (!strcmp(var, "core.symlinks")) {
 692                 has_symlinks = git_config_bool(var, value);
 693                 return 0;
 694         }
 695
 696         if (!strcmp(var, "core.ignorecase")) {
 697                 ignore_case = git_config_bool(var, value);
 698                 return 0;
 699         }
 700
 701         if (!strcmp(var, "core.attributesfile"))
 702                 return git_config_pathname(&git_attributes_file, var, value);
 703
 704         if (!strcmp(var, "core.bare")) {
 705                 is_bare_repository_cfg = git_config_bool(var, value);
 706                 return 0;
 707         }
 708
 709         if (!strcmp(var, "core.ignorestat")) {
 710                 assume_unchanged = git_config_bool(var, value);
 711                 return 0;
 712         }
 713
 714         if (!strcmp(var, "core.prefersymlinkrefs")) {
 715                 prefer_symlink_refs = git_config_bool(var, value);
 716                 return 0;
 717         }
 718
 719         if (!strcmp(var, "core.logallrefupdates")) {
 720                 log_all_ref_updates = git_config_bool(var, value);
 721                 return 0;
 722         }
 723
 724         if (!strcmp(var, "core.warnambiguousrefs")) {
 725                 warn_ambiguous_refs = git_config_bool(var, value);
 726                 return 0;
 727         }
 728
 729         if (!strcmp(var, "core.abbrev")) {
 730                 int abbrev = git_config_int(var, value);
 731                 if (abbrev < minimum_abbrev || abbrev > 40)
 732                         return -1;
 733                 default_abbrev = abbrev;
 734                 return 0;
 735         }
 736
 737         if (!strcmp(var, "core.loosecompression")) {
 738                 int level = git_config_int(var, value);
 739                 if (level == -1)
 740                         level = Z_DEFAULT_COMPRESSION;
 741                 else if (level < 0 || level > Z_BEST_COMPRESSION)
 742                         die("bad zlib compression level %d", level);
 743                 zlib_compression_level = level;
 744                 zlib_compression_seen = 1;
 745                 return 0;
 746         }
 747
 748         if (!strcmp(var, "core.compression")) {
 749                 int level = git_config_int(var, value);
 750                 if (level == -1)
 751                         level = Z_DEFAULT_COMPRESSION;
 752                 else if (level < 0 || level > Z_BEST_COMPRESSION)
 753                         die("bad zlib compression level %d", level);
 754                 core_compression_level = level;
 755                 core_compression_seen = 1;
 756                 if (!zlib_compression_seen)
 757                         zlib_compression_level = level;
 758                 return 0;
 759         }
 760
 761         if (!strcmp(var, "core.packedgitwindowsize")) {
 762                 int pgsz_x2 = getpagesize() * 2;
 763                 packed_git_window_size = git_config_ulong(var, value);
 764
 765                 /* This value must be multiple of (pagesize * 2) */
 766                 packed_git_window_size /= pgsz_x2;
 767                 if (packed_git_window_size < 1)
 768                         packed_git_window_size = 1;
 769                 packed_git_window_size *= pgsz_x2;
 770                 return 0;
 771         }
 772
 773         if (!strcmp(var, "core.bigfilethreshold")) {
 774                 big_file_threshold = git_config_ulong(var, value);
 775                 return 0;
 776         }
 777
 778         if (!strcmp(var, "core.packedgitlimit")) {
 779                 packed_git_limit = git_config_ulong(var, value);
 780                 return 0;
 781         }
 782
 783         if (!strcmp(var, "core.deltabasecachelimit")) {
 784                 delta_base_cache_limit = git_config_ulong(var, value);
 785                 return 0;
 786         }
 787
 788         if (!strcmp(var, "core.autocrlf")) {
 789                 if (value && !strcasecmp(value, "input")) {
 790                         if (core_eol == EOL_CRLF)
 791                                 return error("core.autocrlf=input conflicts with core.eol=crlf");
 792                         auto_crlf = AUTO_CRLF_INPUT;
 793                         return 0;
 794                 }
 795                 auto_crlf = git_config_bool(var, value);
 796                 return 0;
 797         }
 798
 799         if (!strcmp(var, "core.safecrlf")) {
 800                 if (value && !strcasecmp(value, "warn")) {
 801                         safe_crlf = SAFE_CRLF_WARN;
 802                         return 0;
 803                 }
 804                 safe_crlf = git_config_bool(var, value);
 805                 return 0;
 806         }
 807
 808         if (!strcmp(var, "core.eol")) {
 809                 if (value && !strcasecmp(value, "lf"))
 810                         core_eol = EOL_LF;
 811                 else if (value && !strcasecmp(value, "crlf"))
 812                         core_eol = EOL_CRLF;
 813                 else if (value && !strcasecmp(value, "native"))
 814                         core_eol = EOL_NATIVE;
 815                 else
 816                         core_eol = EOL_UNSET;
 817                 if (core_eol == EOL_CRLF && auto_crlf == AUTO_CRLF_INPUT)
 818                         return error("core.autocrlf=input conflicts with core.eol=crlf");
 819                 return 0;
 820         }
 821
 822         if (!strcmp(var, "core.notesref")) {
 823                 notes_ref_name = xstrdup(value);
 824                 return 0;
 825         }
 826
 827         if (!strcmp(var, "core.pager"))
 828                 return git_config_string(&pager_program, var, value);
 829
 830         if (!strcmp(var, "core.editor"))
 831                 return git_config_string(&editor_program, var, value);
 832
 833         if (!strcmp(var, "core.commentchar")) {
 834                 const char *comment;
 835                 int ret = git_config_string(&comment, var, value);
 836                 if (!ret)
 837                         comment_line_char = comment[0];
 838                 return ret;
 839         }
 840
 841         if (!strcmp(var, "core.askpass"))
 842                 return git_config_string(&askpass_program, var, value);
 843
 844         if (!strcmp(var, "core.excludesfile"))
 845                 return git_config_pathname(&excludes_file, var, value);
 846
 847         if (!strcmp(var, "core.whitespace")) {
 848                 if (!value)
 849                         return config_error_nonbool(var);
 850                 whitespace_rule_cfg = parse_whitespace_rule(value);
 851                 return 0;
 852         }
 853
 854         if (!strcmp(var, "core.fsyncobjectfiles")) {
 855                 fsync_object_files = git_config_bool(var, value);
 856                 return 0;
 857         }
 858
 859         if (!strcmp(var, "core.preloadindex")) {
 860                 core_preload_index = git_config_bool(var, value);
 861                 return 0;
 862         }
 863
 864         if (!strcmp(var, "core.createobject")) {
 865                 if (!strcmp(value, "rename"))
 866                         object_creation_mode = OBJECT_CREATION_USES_RENAMES;
 867                 else if (!strcmp(value, "link"))
 868                         object_creation_mode = OBJECT_CREATION_USES_HARDLINKS;
 869                 else
 870                         die("Invalid mode for object creation: %s", value);
 871                 return 0;
 872         }
 873
 874         if (!strcmp(var, "core.sparsecheckout")) {
 875                 core_apply_sparse_checkout = git_config_bool(var, value);
 876                 return 0;
 877         }
 878
 879         if (!strcmp(var, "core.precomposeunicode")) {
 880                 precomposed_unicode = git_config_bool(var, value);
 881                 return 0;
 882         }
 883
 884         if (!strcmp(var, "core.hidedotfiles")) {
 885                 if (value && !strcasecmp(value, "dotgitonly")) {
 886                         hide_dotfiles = HIDE_DOTFILES_DOTGITONLY;
 887                         return 0;
 888                 }
 889                 hide_dotfiles = git_config_bool(var, value);
 890                 return 0;
 891         }
 892
 893         /* Add other config variables here and to Documentation/config.txt. */
 894         return 0;
 895 }
 896
 897 static int git_default_i18n_config(const char *var, const char *value)
 898 {
 899         if (!strcmp(var, "i18n.commitencoding"))
 900                 return git_config_string(&git_commit_encoding, var, value);
 901
 902         if (!strcmp(var, "i18n.logoutputencoding"))
 903                 return git_config_string(&git_log_output_encoding, var, value);
 904
 905         /* Add other config variables here and to Documentation/config.txt. */
 906         return 0;
 907 }
 908
 909 static int git_default_branch_config(const char *var, const char *value)
 910 {
 911         if (!strcmp(var, "branch.autosetupmerge")) {
 912                 if (value && !strcasecmp(value, "always")) {
 913                         git_branch_track = BRANCH_TRACK_ALWAYS;
 914                         return 0;
 915                 }
 916                 git_branch_track = git_config_bool(var, value);
 917                 return 0;
 918         }
 919         if (!strcmp(var, "branch.autosetuprebase")) {
 920                 if (!value)
 921                         return config_error_nonbool(var);
 922                 else if (!strcmp(value, "never"))
 923                         autorebase = AUTOREBASE_NEVER;
 924                 else if (!strcmp(value, "local"))
 925                         autorebase = AUTOREBASE_LOCAL;
 926                 else if (!strcmp(value, "remote"))
 927                         autorebase = AUTOREBASE_REMOTE;
 928                 else if (!strcmp(value, "always"))
 929                         autorebase = AUTOREBASE_ALWAYS;
 930                 else
 931                         return error("Malformed value for %s", var);
 932                 return 0;
 933         }
 934
 935         /* Add other config variables here and to Documentation/config.txt. */
 936         return 0;
 937 }
 938
 939 static int git_default_push_config(const char *var, const char *value)
 940 {
 941         if (!strcmp(var, "push.default")) {
 942                 if (!value)
 943                         return config_error_nonbool(var);
 944                 else if (!strcmp(value, "nothing"))
 945                         push_default = PUSH_DEFAULT_NOTHING;
 946                 else if (!strcmp(value, "matching"))
 947                         push_default = PUSH_DEFAULT_MATCHING;
 948                 else if (!strcmp(value, "simple"))
 949                         push_default = PUSH_DEFAULT_SIMPLE;
 950                 else if (!strcmp(value, "upstream"))
 951                         push_default = PUSH_DEFAULT_UPSTREAM;
 952                 else if (!strcmp(value, "tracking")) /* deprecated */
 953                         push_default = PUSH_DEFAULT_UPSTREAM;
 954                 else if (!strcmp(value, "current"))
 955                         push_default = PUSH_DEFAULT_CURRENT;
 956                 else {
 957                         error("Malformed value for %s: %s", var, value);
 958                         return error("Must be one of nothing, matching, simple, "
 959                                      "upstream or current.");
 960                 }
 961                 return 0;
 962         }
 963
 964         /* Add other config variables here and to Documentation/config.txt. */
 965         return 0;
 966 }
 967
 968 static int git_default_mailmap_config(const char *var, const char *value)
 969 {
 970         if (!strcmp(var, "mailmap.file"))
 971                 return git_config_string(&git_mailmap_file, var, value);
 972         if (!strcmp(var, "mailmap.blob"))
 973                 return git_config_string(&git_mailmap_blob, var, value);
 974
 975         /* Add other config variables here and to Documentation/config.txt. */
 976         return 0;
 977 }
 978
 979 int git_default_config(const char *var, const char *value, void *dummy)
 980 {
 981         if (!prefixcmp(var, "core."))
 982                 return git_default_core_config(var, value);
 983
 984         if (!prefixcmp(var, "user."))
 985                 return git_ident_config(var, value, dummy);
 986
 987         if (!prefixcmp(var, "i18n."))
 988                 return git_default_i18n_config(var, value);
 989
 990         if (!prefixcmp(var, "branch."))
 991                 return git_default_branch_config(var, value);
 992
 993         if (!prefixcmp(var, "push."))
 994                 return git_default_push_config(var, value);
 995
 996         if (!prefixcmp(var, "mailmap."))
 997                 return git_default_mailmap_config(var, value);
 998
 999         if (!prefixcmp(var, "advice."))
1000                 return git_default_advice_config(var, value);
1001
1002         if (!strcmp(var, "pager.color") || !strcmp(var, "color.pager")) {
1003                 pager_use_color = git_config_bool(var,value);
1004                 return 0;
1005         }
1006
1007         if (!strcmp(var, "pack.packsizelimit")) {
1008                 pack_size_limit_cfg = git_config_ulong(var, value);
1009                 return 0;
1010         }
1011         /* Add other config variables here and to Documentation/config.txt. */
1012         return 0;
1013 }
1014
1015 /*
1016  * All source specific fields in the union, die_on_error, name and the callbacks
1017  * fgetc, ungetc, ftell of top need to be initialized before calling
1018  * this function.
1019  */
1020 static int do_config_from(struct config_source *top, config_fn_t fn, void *data)
1021 {
1022         int ret;
1023
1024         /* push config-file parsing state stack */
1025         top->prev = cf;
1026         top->linenr = 1;
1027         top->eof = 0;
1028         strbuf_init(&top->value, 1024);
1029         strbuf_init(&top->var, 1024);
1030         cf = top;
1031
1032         ret = git_parse_source(fn, data);
1033
1034         /* pop config-file parsing state stack */
1035         strbuf_release(&top->value);
1036         strbuf_release(&top->var);
1037         cf = top->prev;
1038
1039         return ret;
1040 }
1041
1042 int git_config_from_file(config_fn_t fn, const char *filename, void *data)
1043 {
1044         int ret;
1045         FILE *f = fopen(filename, "r");
1046
1047         ret = -1;
1048         if (f) {
1049                 struct config_source top;
1050
1051                 top.u.file = f;
1052                 top.name = filename;
1053                 top.die_on_error = 1;
1054                 top.do_fgetc = config_file_fgetc;
1055                 top.do_ungetc = config_file_ungetc;
1056                 top.do_ftell = config_file_ftell;
1057
1058                 ret = do_config_from(&top, fn, data);
1059
1060                 fclose(f);
1061         }
1062         return ret;
1063 }
1064
1065 int git_config_from_buf(config_fn_t fn, const char *name, const char *buf,
1066                         size_t len, void *data)
1067 {
1068         struct config_source top;
1069
1070         top.u.buf.buf = buf;
1071         top.u.buf.len = len;
1072         top.u.buf.pos = 0;
1073         top.name = name;
1074         top.die_on_error = 0;
1075         top.do_fgetc = config_buf_fgetc;
1076         top.do_ungetc = config_buf_ungetc;
1077         top.do_ftell = config_buf_ftell;
1078
1079         return do_config_from(&top, fn, data);
1080 }
1081
1082 static int git_config_from_blob_sha1(config_fn_t fn,
1083                                      const char *name,
1084                                      const unsigned char *sha1,
1085                                      void *data)
1086 {
1087         enum object_type type;
1088         char *buf;
1089         unsigned long size;
1090         int ret;
1091
1092         buf = read_sha1_file(sha1, &type, &size);
1093         if (!buf)
1094                 return error("unable to load config blob object '%s'", name);
1095         if (type != OBJ_BLOB) {
1096                 free(buf);
1097                 return error("reference '%s' does not point to a blob", name);
1098         }
1099
1100         ret = git_config_from_buf(fn, name, buf, size, data);
1101         free(buf);
1102
1103         return ret;
1104 }
1105
1106 static int git_config_from_blob_ref(config_fn_t fn,
1107                                     const char *name,
1108                                     void *data)
1109 {
1110         unsigned char sha1[20];
1111
1112         if (get_sha1(name, sha1) < 0)
1113                 return error("unable to resolve config blob '%s'", name);
1114         return git_config_from_blob_sha1(fn, name, sha1, data);
1115 }
1116
1117 const char *git_etc_gitconfig(void)
1118 {
1119         static const char *system_wide;
1120         if (!system_wide)
1121                 system_wide = system_path(ETC_GITCONFIG);
1122         return system_wide;
1123 }
1124
1125 int git_env_bool(const char *k, int def)
1126 {
1127         const char *v = getenv(k);
1128         return v ? git_config_bool(k, v) : def;
1129 }
1130
1131 int git_config_system(void)
1132 {
1133         return !git_env_bool("GIT_CONFIG_NOSYSTEM", 0);
1134 }
1135
1136 int git_config_early(config_fn_t fn, void *data, const char *repo_config)
1137 {
1138         int ret = 0, found = 0;
1139         char *xdg_config = NULL;
1140         char *user_config = NULL;
1141
1142         home_config_paths(&user_config, &xdg_config, "config");
1143
1144         if (git_config_system() && !access_or_die(git_etc_gitconfig(), R_OK, 0)) {
1145                 ret += git_config_from_file(fn, git_etc_gitconfig(),
1146                                             data);
1147                 found += 1;
1148         }
1149
1150         if (xdg_config && !access_or_die(xdg_config, R_OK, ACCESS_EACCES_OK)) {
1151                 ret += git_config_from_file(fn, xdg_config, data);
1152                 found += 1;
1153         }
1154
1155         if (user_config && !access_or_die(user_config, R_OK, ACCESS_EACCES_OK)) {
1156                 ret += git_config_from_file(fn, user_config, data);
1157                 found += 1;
1158         }
1159
1160         if (repo_config && !access_or_die(repo_config, R_OK, 0)) {
1161                 ret += git_config_from_file(fn, repo_config, data);
1162                 found += 1;
1163         }
1164
1165         switch (git_config_from_parameters(fn, data)) {
1166         case -1: /* error */
1167                 die("unable to parse command-line config");
1168                 break;
1169         case 0: /* found nothing */
1170                 break;
1171         default: /* found at least one item */
1172                 found++;
1173                 break;
1174         }
1175
1176         free(xdg_config);
1177         free(user_config);
1178         return ret == 0 ? found : ret;
1179 }
1180
1181 int git_config_with_options(config_fn_t fn, void *data,
1182                             const char *filename,
1183                             const char *blob_ref,
1184                             int respect_includes)
1185 {
1186         char *repo_config = NULL;
1187         int ret;
1188         struct config_include_data inc = CONFIG_INCLUDE_INIT;
1189
1190         if (respect_includes) {
1191                 inc.fn = fn;
1192                 inc.data = data;
1193                 fn = git_config_include;
1194                 data = &inc;
1195         }
1196
1197         /*
1198          * If we have a specific filename, use it. Otherwise, follow the
1199          * regular lookup sequence.
1200          */
1201         if (filename)
1202                 return git_config_from_file(fn, filename, data);
1203         else if (blob_ref)
1204                 return git_config_from_blob_ref(fn, blob_ref, data);
1205
1206         repo_config = git_pathdup("config");
1207         ret = git_config_early(fn, data, repo_config);
1208         if (repo_config)
1209                 free(repo_config);
1210         return ret;
1211 }
1212
1213 int git_config(config_fn_t fn, void *data)
1214 {
1215         return git_config_with_options(fn, data, NULL, NULL, 1);
1216 }
1217
1218 /*
1219  * Find all the stuff for git_config_set() below.
1220  */
1221
1222 #define MAX_MATCHES 512
1223
1224 static struct {
1225         int baselen;
1226         char *key;
1227         int do_not_match;
1228         regex_t *value_regex;
1229         int multi_replace;
1230         size_t offset[MAX_MATCHES];
1231         enum { START, SECTION_SEEN, SECTION_END_SEEN, KEY_SEEN } state;
1232         int seen;
1233 } store;
1234
1235 static int matches(const char *key, const char *value)
1236 {
1237         return !strcmp(key, store.key) &&
1238                 (store.value_regex == NULL ||
1239                  (store.do_not_match ^
1240                   !regexec(store.value_regex, value, 0, NULL, 0)));
1241 }
1242
1243 static int store_aux(const char *key, const char *value, void *cb)
1244 {
1245         const char *ep;
1246         size_t section_len;
1247
1248         switch (store.state) {
1249         case KEY_SEEN:
1250                 if (matches(key, value)) {
1251                         if (store.seen == 1 && store.multi_replace == 0) {
1252                                 warning("%s has multiple values", key);
1253                         } else if (store.seen >= MAX_MATCHES) {
1254                                 error("too many matches for %s", key);
1255                                 return 1;
1256                         }
1257
1258                         store.offset[store.seen] = cf->do_ftell(cf);
1259                         store.seen++;
1260                 }
1261                 break;
1262         case SECTION_SEEN:
1263                 /*
1264                  * What we are looking for is in store.key (both
1265                  * section and var), and its section part is baselen
1266                  * long.  We found key (again, both section and var).
1267                  * We would want to know if this key is in the same
1268                  * section as what we are looking for.  We already
1269                  * know we are in the same section as what should
1270                  * hold store.key.
1271                  */
1272                 ep = strrchr(key, '.');
1273                 section_len = ep - key;
1274
1275                 if ((section_len != store.baselen) ||
1276                     memcmp(key, store.key, section_len+1)) {
1277                         store.state = SECTION_END_SEEN;
1278                         break;
1279                 }
1280
1281                 /*
1282                  * Do not increment matches: this is no match, but we
1283                  * just made sure we are in the desired section.
1284                  */
1285                 store.offset[store.seen] = cf->do_ftell(cf);
1286                 /* fallthru */
1287         case SECTION_END_SEEN:
1288         case START:
1289                 if (matches(key, value)) {
1290                         store.offset[store.seen] = cf->do_ftell(cf);
1291                         store.state = KEY_SEEN;
1292                         store.seen++;
1293                 } else {
1294                         if (strrchr(key, '.') - key == store.baselen &&
1295                               !strncmp(key, store.key, store.baselen)) {
1296                                         store.state = SECTION_SEEN;
1297                                         store.offset[store.seen] = cf->do_ftell(cf);
1298                         }
1299                 }
1300         }
1301         return 0;
1302 }
1303
1304 static int write_error(const char *filename)
1305 {
1306         error("failed to write new configuration file %s", filename);
1307
1308         /* Same error code as "failed to rename". */
1309         return 4;
1310 }
1311
1312 static int store_write_section(int fd, const char *key)
1313 {
1314         const char *dot;
1315         int i, success;
1316         struct strbuf sb = STRBUF_INIT;
1317
1318         dot = memchr(key, '.', store.baselen);
1319         if (dot) {
1320                 strbuf_addf(&sb, "[%.*s \"", (int)(dot - key), key);
1321                 for (i = dot - key + 1; i < store.baselen; i++) {
1322                         if (key[i] == '"' || key[i] == '\\')
1323                                 strbuf_addch(&sb, '\\');
1324                         strbuf_addch(&sb, key[i]);
1325                 }
1326                 strbuf_addstr(&sb, "\"]\n");
1327         } else {
1328                 strbuf_addf(&sb, "[%.*s]\n", store.baselen, key);
1329         }
1330
1331         success = write_in_full(fd, sb.buf, sb.len) == sb.len;
1332         strbuf_release(&sb);
1333
1334         return success;
1335 }
1336
1337 static int store_write_pair(int fd, const char *key, const char *value)
1338 {
1339         int i, success;
1340         int length = strlen(key + store.baselen + 1);
1341         const char *quote = "";
1342         struct strbuf sb = STRBUF_INIT;
1343
1344         /*
1345          * Check to see if the value needs to be surrounded with a dq pair.
1346          * Note that problematic characters are always backslash-quoted; this
1347          * check is about not losing leading or trailing SP and strings that
1348          * follow beginning-of-comment characters (i.e. ';' and '#') by the
1349          * configuration parser.
1350          */
1351         if (value[0] == ' ')
1352                 quote = "\"";
1353         for (i = 0; value[i]; i++)
1354                 if (value[i] == ';' || value[i] == '#')
1355                         quote = "\"";
1356         if (i && value[i - 1] == ' ')
1357                 quote = "\"";
1358
1359         strbuf_addf(&sb, "\t%.*s = %s",
1360                     length, key + store.baselen + 1, quote);
1361
1362         for (i = 0; value[i]; i++)
1363                 switch (value[i]) {
1364                 case '\n':
1365                         strbuf_addstr(&sb, "\\n");
1366                         break;
1367                 case '\t':
1368                         strbuf_addstr(&sb, "\\t");
1369                         break;
1370                 case '"':
1371                 case '\\':
1372                         strbuf_addch(&sb, '\\');
1373                 default:
1374                         strbuf_addch(&sb, value[i]);
1375                         break;
1376                 }
1377         strbuf_addf(&sb, "%s\n", quote);
1378
1379         success = write_in_full(fd, sb.buf, sb.len) == sb.len;
1380         strbuf_release(&sb);
1381
1382         return success;
1383 }
1384
1385 static ssize_t find_beginning_of_line(const char *contents, size_t size,
1386         size_t offset_, int *found_bracket)
1387 {
1388         size_t equal_offset = size, bracket_offset = size;
1389         ssize_t offset;
1390
1391 contline:
1392         for (offset = offset_-2; offset > 0
1393                         && contents[offset] != '\n'; offset--)
1394                 switch (contents[offset]) {
1395                         case '=': equal_offset = offset; break;
1396                         case ']': bracket_offset = offset; break;
1397                 }
1398         if (offset > 0 && contents[offset-1] == '\\') {
1399                 offset_ = offset;
1400                 goto contline;
1401         }
1402         if (bracket_offset < equal_offset) {
1403                 *found_bracket = 1;
1404                 offset = bracket_offset+1;
1405         } else
1406                 offset++;
1407
1408         return offset;
1409 }
1410
1411 int git_config_set_in_file(const char *config_filename,
1412                         const char *key, const char *value)
1413 {
1414         return git_config_set_multivar_in_file(config_filename, key, value, NULL, 0);
1415 }
1416
1417 int git_config_set(const char *key, const char *value)
1418 {
1419         return git_config_set_multivar(key, value, NULL, 0);
1420 }
1421
1422 /*
1423  * Auxiliary function to sanity-check and split the key into the section
1424  * identifier and variable name.
1425  *
1426  * Returns 0 on success, -1 when there is an invalid character in the key and
1427  * -2 if there is no section name in the key.
1428  *
1429  * store_key - pointer to char* which will hold a copy of the key with
1430  *             lowercase section and variable name
1431  * baselen - pointer to int which will hold the length of the
1432  *           section + subsection part, can be NULL
1433  */
1434 int git_config_parse_key(const char *key, char **store_key, int *baselen_)
1435 {
1436         int i, dot, baselen;
1437         const char *last_dot = strrchr(key, '.');
1438
1439         /*
1440          * Since "key" actually contains the section name and the real
1441          * key name separated by a dot, we have to know where the dot is.
1442          */
1443
1444         if (last_dot == NULL || last_dot == key) {
1445                 error("key does not contain a section: %s", key);
1446                 return -CONFIG_NO_SECTION_OR_NAME;
1447         }
1448
1449         if (!last_dot[1]) {
1450                 error("key does not contain variable name: %s", key);
1451                 return -CONFIG_NO_SECTION_OR_NAME;
1452         }
1453
1454         baselen = last_dot - key;
1455         if (baselen_)
1456                 *baselen_ = baselen;
1457
1458         /*
1459          * Validate the key and while at it, lower case it for matching.
1460          */
1461         *store_key = xmalloc(strlen(key) + 1);
1462
1463         dot = 0;
1464         for (i = 0; key[i]; i++) {
1465                 unsigned char c = key[i];
1466                 if (c == '.')
1467                         dot = 1;
1468                 /* Leave the extended basename untouched.. */
1469                 if (!dot || i > baselen) {
1470                         if (!iskeychar(c) ||
1471                             (i == baselen + 1 && !isalpha(c))) {
1472                                 error("invalid key: %s", key);
1473                                 goto out_free_ret_1;
1474                         }
1475                         c = tolower(c);
1476                 } else if (c == '\n') {
1477                         error("invalid key (newline): %s", key);
1478                         goto out_free_ret_1;
1479                 }
1480                 (*store_key)[i] = c;
1481         }
1482         (*store_key)[i] = 0;
1483
1484         return 0;
1485
1486 out_free_ret_1:
1487         free(*store_key);
1488         *store_key = NULL;
1489         return -CONFIG_INVALID_KEY;
1490 }
1491
1492 /*
1493  * If value==NULL, unset in (remove from) config,
1494  * if value_regex!=NULL, disregard key/value pairs where value does not match.
1495  * if multi_replace==0, nothing, or only one matching key/value is replaced,
1496  *     else all matching key/values (regardless how many) are removed,
1497  *     before the new pair is written.
1498  *
1499  * Returns 0 on success.
1500  *
1501  * This function does this:
1502  *
1503  * - it locks the config file by creating ".git/config.lock"
1504  *
1505  * - it then parses the config using store_aux() as validator to find
1506  *   the position on the key/value pair to replace. If it is to be unset,
1507  *   it must be found exactly once.
1508  *
1509  * - the config file is mmap()ed and the part before the match (if any) is
1510  *   written to the lock file, then the changed part and the rest.
1511  *
1512  * - the config file is removed and the lock file rename()d to it.
1513  *
1514  */
1515 int git_config_set_multivar_in_file(const char *config_filename,
1516                                 const char *key, const char *value,
1517                                 const char *value_regex, int multi_replace)
1518 {
1519         int fd = -1, in_fd;
1520         int ret;
1521         struct lock_file *lock = NULL;
1522         char *filename_buf = NULL;
1523
1524         /* parse-key returns negative; flip the sign to feed exit(3) */
1525         ret = 0 - git_config_parse_key(key, &store.key, &store.baselen);
1526         if (ret)
1527                 goto out_free;
1528
1529         store.multi_replace = multi_replace;
1530
1531         if (!config_filename)
1532                 config_filename = filename_buf = git_pathdup("config");
1533
1534         /*
1535          * The lock serves a purpose in addition to locking: the new
1536          * contents of .git/config will be written into it.
1537          */
1538         lock = xcalloc(sizeof(struct lock_file), 1);
1539         fd = hold_lock_file_for_update(lock, config_filename, 0);
1540         if (fd < 0) {
1541                 error("could not lock config file %s: %s", config_filename, strerror(errno));
1542                 free(store.key);
1543                 ret = CONFIG_NO_LOCK;
1544                 goto out_free;
1545         }
1546
1547         /*
1548          * If .git/config does not exist yet, write a minimal version.
1549          */
1550         in_fd = open(config_filename, O_RDONLY);
1551         if ( in_fd < 0 ) {
1552                 free(store.key);
1553
1554                 if ( ENOENT != errno ) {
1555                         error("opening %s: %s", config_filename,
1556                               strerror(errno));
1557                         ret = CONFIG_INVALID_FILE; /* same as "invalid config file" */
1558                         goto out_free;
1559                 }
1560                 /* if nothing to unset, error out */
1561                 if (value == NULL) {
1562                         ret = CONFIG_NOTHING_SET;
1563                         goto out_free;
1564                 }
1565
1566                 store.key = (char *)key;
1567                 if (!store_write_section(fd, key) ||
1568                     !store_write_pair(fd, key, value))
1569                         goto write_err_out;
1570         } else {
1571                 struct stat st;
1572                 char *contents;
1573                 size_t contents_sz, copy_begin, copy_end;
1574                 int i, new_line = 0;
1575
1576                 if (value_regex == NULL)
1577                         store.value_regex = NULL;
1578                 else {
1579                         if (value_regex[0] == '!') {
1580                                 store.do_not_match = 1;
1581                                 value_regex++;
1582                         } else
1583                                 store.do_not_match = 0;
1584
1585                         store.value_regex = (regex_t*)xmalloc(sizeof(regex_t));
1586                         if (regcomp(store.value_regex, value_regex,
1587                                         REG_EXTENDED)) {
1588                                 error("invalid pattern: %s", value_regex);
1589                                 free(store.value_regex);
1590                                 ret = CONFIG_INVALID_PATTERN;
1591                                 goto out_free;
1592                         }
1593                 }
1594
1595                 store.offset[0] = 0;
1596                 store.state = START;
1597                 store.seen = 0;
1598
1599                 /*
1600                  * After this, store.offset will contain the *end* offset
1601                  * of the last match, or remain at 0 if no match was found.
1602                  * As a side effect, we make sure to transform only a valid
1603                  * existing config file.
1604                  */
1605                 if (git_config_from_file(store_aux, config_filename, NULL)) {
1606                         error("invalid config file %s", config_filename);
1607                         free(store.key);
1608                         if (store.value_regex != NULL) {
1609                                 regfree(store.value_regex);
1610                                 free(store.value_regex);
1611                         }
1612                         ret = CONFIG_INVALID_FILE;
1613                         goto out_free;
1614                 }
1615
1616                 free(store.key);
1617                 if (store.value_regex != NULL) {
1618                         regfree(store.value_regex);
1619                         free(store.value_regex);
1620                 }
1621
1622                 /* if nothing to unset, or too many matches, error out */
1623                 if ((store.seen == 0 && value == NULL) ||
1624                                 (store.seen > 1 && multi_replace == 0)) {
1625                         ret = CONFIG_NOTHING_SET;
1626                         goto out_free;
1627                 }
1628
1629                 fstat(in_fd, &st);
1630                 contents_sz = xsize_t(st.st_size);
1631                 contents = xmmap(NULL, contents_sz, PROT_READ,
1632                         MAP_PRIVATE, in_fd, 0);
1633                 close(in_fd);
1634
1635                 if (store.seen == 0)
1636                         store.seen = 1;
1637
1638                 for (i = 0, copy_begin = 0; i < store.seen; i++) {
1639                         if (store.offset[i] == 0) {
1640                                 store.offset[i] = copy_end = contents_sz;
1641                         } else if (store.state != KEY_SEEN) {
1642                                 copy_end = store.offset[i];
1643                         } else
1644                                 copy_end = find_beginning_of_line(
1645                                         contents, contents_sz,
1646                                         store.offset[i]-2, &new_line);
1647
1648                         if (copy_end > 0 && contents[copy_end-1] != '\n')
1649                                 new_line = 1;
1650
1651                         /* write the first part of the config */
1652                         if (copy_end > copy_begin) {
1653                                 if (write_in_full(fd, contents + copy_begin,
1654                                                   copy_end - copy_begin) <
1655                                     copy_end - copy_begin)
1656                                         goto write_err_out;
1657                                 if (new_line &&
1658                                     write_str_in_full(fd, "\n") != 1)
1659                                         goto write_err_out;
1660                         }
1661                         copy_begin = store.offset[i];
1662                 }
1663
1664                 /* write the pair (value == NULL means unset) */
1665                 if (value != NULL) {
1666                         if (store.state == START) {
1667                                 if (!store_write_section(fd, key))
1668                                         goto write_err_out;
1669                         }
1670                         if (!store_write_pair(fd, key, value))
1671                                 goto write_err_out;
1672                 }
1673
1674                 /* write the rest of the config */
1675                 if (copy_begin < contents_sz)
1676                         if (write_in_full(fd, contents + copy_begin,
1677                                           contents_sz - copy_begin) <
1678                             contents_sz - copy_begin)
1679                                 goto write_err_out;
1680
1681                 munmap(contents, contents_sz);
1682         }
1683
1684         if (commit_lock_file(lock) < 0) {
1685                 error("could not commit config file %s", config_filename);
1686                 ret = CONFIG_NO_WRITE;
1687                 goto out_free;
1688         }
1689
1690         /*
1691          * lock is committed, so don't try to roll it back below.
1692          * NOTE: Since lockfile.c keeps a linked list of all created
1693          * lock_file structures, it isn't safe to free(lock).  It's
1694          * better to just leave it hanging around.
1695          */
1696         lock = NULL;
1697         ret = 0;
1698
1699 out_free:
1700         if (lock)
1701                 rollback_lock_file(lock);
1702         free(filename_buf);
1703         return ret;
1704
1705 write_err_out:
1706         ret = write_error(lock->filename);
1707         goto out_free;
1708
1709 }
1710
1711 int git_config_set_multivar(const char *key, const char *value,
1712                         const char *value_regex, int multi_replace)
1713 {
1714         return git_config_set_multivar_in_file(NULL, key, value, value_regex,
1715                                                multi_replace);
1716 }
1717
1718 static int section_name_match (const char *buf, const char *name)
1719 {
1720         int i = 0, j = 0, dot = 0;
1721         if (buf[i] != '[')
1722                 return 0;
1723         for (i = 1; buf[i] && buf[i] != ']'; i++) {
1724                 if (!dot && isspace(buf[i])) {
1725                         dot = 1;
1726                         if (name[j++] != '.')
1727                                 break;
1728                         for (i++; isspace(buf[i]); i++)
1729                                 ; /* do nothing */
1730                         if (buf[i] != '"')
1731                                 break;
1732                         continue;
1733                 }
1734                 if (buf[i] == '\\' && dot)
1735                         i++;
1736                 else if (buf[i] == '"' && dot) {
1737                         for (i++; isspace(buf[i]); i++)
1738                                 ; /* do_nothing */
1739                         break;
1740                 }
1741                 if (buf[i] != name[j++])
1742                         break;
1743         }
1744         if (buf[i] == ']' && name[j] == 0) {
1745                 /*
1746                  * We match, now just find the right length offset by
1747                  * gobbling up any whitespace after it, as well
1748                  */
1749                 i++;
1750                 for (; buf[i] && isspace(buf[i]); i++)
1751                         ; /* do nothing */
1752                 return i;
1753         }
1754         return 0;
1755 }
1756
1757 static int section_name_is_ok(const char *name)
1758 {
1759         /* Empty section names are bogus. */
1760         if (!*name)
1761                 return 0;
1762
1763         /*
1764          * Before a dot, we must be alphanumeric or dash. After the first dot,
1765          * anything goes, so we can stop checking.
1766          */
1767         for (; *name && *name != '.'; name++)
1768                 if (*name != '-' && !isalnum(*name))
1769                         return 0;
1770         return 1;
1771 }
1772
1773 /* if new_name == NULL, the section is removed instead */
1774 int git_config_rename_section_in_file(const char *config_filename,
1775                                       const char *old_name, const char *new_name)
1776 {
1777         int ret = 0, remove = 0;
1778         char *filename_buf = NULL;
1779         struct lock_file *lock;
1780         int out_fd;
1781         char buf[1024];
1782         FILE *config_file;
1783
1784         if (new_name && !section_name_is_ok(new_name)) {
1785                 ret = error("invalid section name: %s", new_name);
1786                 goto out;
1787         }
1788
1789         if (!config_filename)
1790                 config_filename = filename_buf = git_pathdup("config");
1791
1792         lock = xcalloc(sizeof(struct lock_file), 1);
1793         out_fd = hold_lock_file_for_update(lock, config_filename, 0);
1794         if (out_fd < 0) {
1795                 ret = error("could not lock config file %s", config_filename);
1796                 goto out;
1797         }
1798
1799         if (!(config_file = fopen(config_filename, "rb"))) {
1800                 /* no config file means nothing to rename, no error */
1801                 goto unlock_and_out;
1802         }
1803
1804         while (fgets(buf, sizeof(buf), config_file)) {
1805                 int i;
1806                 int length;
1807                 char *output = buf;
1808                 for (i = 0; buf[i] && isspace(buf[i]); i++)
1809                         ; /* do nothing */
1810                 if (buf[i] == '[') {
1811                         /* it's a section */
1812                         int offset = section_name_match(&buf[i], old_name);
1813                         if (offset > 0) {
1814                                 ret++;
1815                                 if (new_name == NULL) {
1816                                         remove = 1;
1817                                         continue;
1818                                 }
1819                                 store.baselen = strlen(new_name);
1820                                 if (!store_write_section(out_fd, new_name)) {
1821                                         ret = write_error(lock->filename);
1822                                         goto out;
1823                                 }
1824                                 /*
1825                                  * We wrote out the new section, with
1826                                  * a newline, now skip the old
1827                                  * section's length
1828                                  */
1829                                 output += offset + i;
1830                                 if (strlen(output) > 0) {
1831                                         /*
1832                                          * More content means there's
1833                                          * a declaration to put on the
1834                                          * next line; indent with a
1835                                          * tab
1836                                          */
1837                                         output -= 1;
1838                                         output[0] = '\t';
1839                                 }
1840                         }
1841                         remove = 0;
1842                 }
1843                 if (remove)
1844                         continue;
1845                 length = strlen(output);
1846                 if (write_in_full(out_fd, output, length) != length) {
1847                         ret = write_error(lock->filename);
1848                         goto out;
1849                 }
1850         }
1851         fclose(config_file);
1852 unlock_and_out:
1853         if (commit_lock_file(lock) < 0)
1854                 ret = error("could not commit config file %s", config_filename);
1855 out:
1856         free(filename_buf);
1857         return ret;
1858 }
1859
1860 int git_config_rename_section(const char *old_name, const char *new_name)
1861 {
1862         return git_config_rename_section_in_file(NULL, old_name, new_name);
1863 }
1864
1865 /*
1866  * Call this to report error for your variable that should not
1867  * get a boolean value (i.e. "[my] var" means "true").
1868  */
1869 #undef config_error_nonbool
1870 int config_error_nonbool(const char *var)
1871 {
1872         return error("Missing value for '%s'", var);
1873 }
1874
1875 int parse_config_key(const char *var,
1876                      const char *section,
1877                      const char **subsection, int *subsection_len,
1878                      const char **key)
1879 {
1880         int section_len = strlen(section);
1881         const char *dot;
1882
1883         /* Does it start with "section." ? */
1884         if (prefixcmp(var, section) || var[section_len] != '.')
1885                 return -1;
1886
1887         /*
1888          * Find the key; we don't know yet if we have a subsection, but we must
1889          * parse backwards from the end, since the subsection may have dots in
1890          * it, too.
1891          */
1892         dot = strrchr(var, '.');
1893         *key = dot + 1;
1894
1895         /* Did we have a subsection at all? */
1896         if (dot == var + section_len) {
1897                 *subsection = NULL;
1898                 *subsection_len = 0;
1899         }
1900         else {
1901                 *subsection = var + section_len + 1;
1902                 *subsection_len = dot - *subsection;
1903         }
1904
1905         return 0;
1906 }