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         if (!strcmp(var, "core.fscache")) {
 894                 core_fscache = git_config_bool(var, value);
 895                 return 0;
 896         }
 897
 898         /* Add other config variables here and to Documentation/config.txt. */
 899         return 0;
 900 }
 901
 902 static int git_default_i18n_config(const char *var, const char *value)
 903 {
 904         if (!strcmp(var, "i18n.commitencoding"))
 905                 return git_config_string(&git_commit_encoding, var, value);
 906
 907         if (!strcmp(var, "i18n.logoutputencoding"))
 908                 return git_config_string(&git_log_output_encoding, var, value);
 909
 910         /* Add other config variables here and to Documentation/config.txt. */
 911         return 0;
 912 }
 913
 914 static int git_default_branch_config(const char *var, const char *value)
 915 {
 916         if (!strcmp(var, "branch.autosetupmerge")) {
 917                 if (value && !strcasecmp(value, "always")) {
 918                         git_branch_track = BRANCH_TRACK_ALWAYS;
 919                         return 0;
 920                 }
 921                 git_branch_track = git_config_bool(var, value);
 922                 return 0;
 923         }
 924         if (!strcmp(var, "branch.autosetuprebase")) {
 925                 if (!value)
 926                         return config_error_nonbool(var);
 927                 else if (!strcmp(value, "never"))
 928                         autorebase = AUTOREBASE_NEVER;
 929                 else if (!strcmp(value, "local"))
 930                         autorebase = AUTOREBASE_LOCAL;
 931                 else if (!strcmp(value, "remote"))
 932                         autorebase = AUTOREBASE_REMOTE;
 933                 else if (!strcmp(value, "always"))
 934                         autorebase = AUTOREBASE_ALWAYS;
 935                 else
 936                         return error("Malformed value for %s", var);
 937                 return 0;
 938         }
 939
 940         /* Add other config variables here and to Documentation/config.txt. */
 941         return 0;
 942 }
 943
 944 static int git_default_push_config(const char *var, const char *value)
 945 {
 946         if (!strcmp(var, "push.default")) {
 947                 if (!value)
 948                         return config_error_nonbool(var);
 949                 else if (!strcmp(value, "nothing"))
 950                         push_default = PUSH_DEFAULT_NOTHING;
 951                 else if (!strcmp(value, "matching"))
 952                         push_default = PUSH_DEFAULT_MATCHING;
 953                 else if (!strcmp(value, "simple"))
 954                         push_default = PUSH_DEFAULT_SIMPLE;
 955                 else if (!strcmp(value, "upstream"))
 956                         push_default = PUSH_DEFAULT_UPSTREAM;
 957                 else if (!strcmp(value, "tracking")) /* deprecated */
 958                         push_default = PUSH_DEFAULT_UPSTREAM;
 959                 else if (!strcmp(value, "current"))
 960                         push_default = PUSH_DEFAULT_CURRENT;
 961                 else {
 962                         error("Malformed value for %s: %s", var, value);
 963                         return error("Must be one of nothing, matching, simple, "
 964                                      "upstream or current.");
 965                 }
 966                 return 0;
 967         }
 968
 969         /* Add other config variables here and to Documentation/config.txt. */
 970         return 0;
 971 }
 972
 973 static int git_default_mailmap_config(const char *var, const char *value)
 974 {
 975         if (!strcmp(var, "mailmap.file"))
 976                 return git_config_string(&git_mailmap_file, var, value);
 977         if (!strcmp(var, "mailmap.blob"))
 978                 return git_config_string(&git_mailmap_blob, var, value);
 979
 980         /* Add other config variables here and to Documentation/config.txt. */
 981         return 0;
 982 }
 983
 984 int git_default_config(const char *var, const char *value, void *dummy)
 985 {
 986         if (!prefixcmp(var, "core."))
 987                 return git_default_core_config(var, value);
 988
 989         if (!prefixcmp(var, "user."))
 990                 return git_ident_config(var, value, dummy);
 991
 992         if (!prefixcmp(var, "i18n."))
 993                 return git_default_i18n_config(var, value);
 994
 995         if (!prefixcmp(var, "branch."))
 996                 return git_default_branch_config(var, value);
 997
 998         if (!prefixcmp(var, "push."))
 999                 return git_default_push_config(var, value);
1000
1001         if (!prefixcmp(var, "mailmap."))
1002                 return git_default_mailmap_config(var, value);
1003
1004         if (!prefixcmp(var, "advice."))
1005                 return git_default_advice_config(var, value);
1006
1007         if (!strcmp(var, "pager.color") || !strcmp(var, "color.pager")) {
1008                 pager_use_color = git_config_bool(var,value);
1009                 return 0;
1010         }
1011
1012         if (!strcmp(var, "pack.packsizelimit")) {
1013                 pack_size_limit_cfg = git_config_ulong(var, value);
1014                 return 0;
1015         }
1016         /* Add other config variables here and to Documentation/config.txt. */
1017         return 0;
1018 }
1019
1020 /*
1021  * All source specific fields in the union, die_on_error, name and the callbacks
1022  * fgetc, ungetc, ftell of top need to be initialized before calling
1023  * this function.
1024  */
1025 static int do_config_from(struct config_source *top, config_fn_t fn, void *data)
1026 {
1027         int ret;
1028
1029         /* push config-file parsing state stack */
1030         top->prev = cf;
1031         top->linenr = 1;
1032         top->eof = 0;
1033         strbuf_init(&top->value, 1024);
1034         strbuf_init(&top->var, 1024);
1035         cf = top;
1036
1037         ret = git_parse_source(fn, data);
1038
1039         /* pop config-file parsing state stack */
1040         strbuf_release(&top->value);
1041         strbuf_release(&top->var);
1042         cf = top->prev;
1043
1044         return ret;
1045 }
1046
1047 int git_config_from_file(config_fn_t fn, const char *filename, void *data)
1048 {
1049         int ret;
1050         FILE *f = fopen(filename, "r");
1051
1052         ret = -1;
1053         if (f) {
1054                 struct config_source top;
1055
1056                 top.u.file = f;
1057                 top.name = filename;
1058                 top.die_on_error = 1;
1059                 top.do_fgetc = config_file_fgetc;
1060                 top.do_ungetc = config_file_ungetc;
1061                 top.do_ftell = config_file_ftell;
1062
1063                 ret = do_config_from(&top, fn, data);
1064
1065                 fclose(f);
1066         }
1067         return ret;
1068 }
1069
1070 int git_config_from_buf(config_fn_t fn, const char *name, const char *buf,
1071                         size_t len, void *data)
1072 {
1073         struct config_source top;
1074
1075         top.u.buf.buf = buf;
1076         top.u.buf.len = len;
1077         top.u.buf.pos = 0;
1078         top.name = name;
1079         top.die_on_error = 0;
1080         top.do_fgetc = config_buf_fgetc;
1081         top.do_ungetc = config_buf_ungetc;
1082         top.do_ftell = config_buf_ftell;
1083
1084         return do_config_from(&top, fn, data);
1085 }
1086
1087 static int git_config_from_blob_sha1(config_fn_t fn,
1088                                      const char *name,
1089                                      const unsigned char *sha1,
1090                                      void *data)
1091 {
1092         enum object_type type;
1093         char *buf;
1094         unsigned long size;
1095         int ret;
1096
1097         buf = read_sha1_file(sha1, &type, &size);
1098         if (!buf)
1099                 return error("unable to load config blob object '%s'", name);
1100         if (type != OBJ_BLOB) {
1101                 free(buf);
1102                 return error("reference '%s' does not point to a blob", name);
1103         }
1104
1105         ret = git_config_from_buf(fn, name, buf, size, data);
1106         free(buf);
1107
1108         return ret;
1109 }
1110
1111 static int git_config_from_blob_ref(config_fn_t fn,
1112                                     const char *name,
1113                                     void *data)
1114 {
1115         unsigned char sha1[20];
1116
1117         if (get_sha1(name, sha1) < 0)
1118                 return error("unable to resolve config blob '%s'", name);
1119         return git_config_from_blob_sha1(fn, name, sha1, data);
1120 }
1121
1122 const char *git_etc_gitconfig(void)
1123 {
1124         static const char *system_wide;
1125         if (!system_wide)
1126                 system_wide = system_path(ETC_GITCONFIG);
1127         return system_wide;
1128 }
1129
1130 int git_env_bool(const char *k, int def)
1131 {
1132         const char *v = getenv(k);
1133         return v ? git_config_bool(k, v) : def;
1134 }
1135
1136 int git_config_system(void)
1137 {
1138         return !git_env_bool("GIT_CONFIG_NOSYSTEM", 0);
1139 }
1140
1141 int git_config_early(config_fn_t fn, void *data, const char *repo_config)
1142 {
1143         int ret = 0, found = 0;
1144         char *xdg_config = NULL;
1145         char *user_config = NULL;
1146
1147         home_config_paths(&user_config, &xdg_config, "config");
1148
1149         if (git_config_system() && !access_or_die(git_etc_gitconfig(), R_OK, 0)) {
1150                 ret += git_config_from_file(fn, git_etc_gitconfig(),
1151                                             data);
1152                 found += 1;
1153         }
1154
1155         if (xdg_config && !access_or_die(xdg_config, R_OK, ACCESS_EACCES_OK)) {
1156                 ret += git_config_from_file(fn, xdg_config, data);
1157                 found += 1;
1158         }
1159
1160         if (user_config && !access_or_die(user_config, R_OK, ACCESS_EACCES_OK)) {
1161                 ret += git_config_from_file(fn, user_config, data);
1162                 found += 1;
1163         }
1164
1165         if (repo_config && !access_or_die(repo_config, R_OK, 0)) {
1166                 ret += git_config_from_file(fn, repo_config, data);
1167                 found += 1;
1168         }
1169
1170         switch (git_config_from_parameters(fn, data)) {
1171         case -1: /* error */
1172                 die("unable to parse command-line config");
1173                 break;
1174         case 0: /* found nothing */
1175                 break;
1176         default: /* found at least one item */
1177                 found++;
1178                 break;
1179         }
1180
1181         free(xdg_config);
1182         free(user_config);
1183         return ret == 0 ? found : ret;
1184 }
1185
1186 int git_config_with_options(config_fn_t fn, void *data,
1187                             const char *filename,
1188                             const char *blob_ref,
1189                             int respect_includes)
1190 {
1191         char *repo_config = NULL;
1192         int ret;
1193         struct config_include_data inc = CONFIG_INCLUDE_INIT;
1194
1195         if (respect_includes) {
1196                 inc.fn = fn;
1197                 inc.data = data;
1198                 fn = git_config_include;
1199                 data = &inc;
1200         }
1201
1202         /*
1203          * If we have a specific filename, use it. Otherwise, follow the
1204          * regular lookup sequence.
1205          */
1206         if (filename)
1207                 return git_config_from_file(fn, filename, data);
1208         else if (blob_ref)
1209                 return git_config_from_blob_ref(fn, blob_ref, data);
1210
1211         repo_config = git_pathdup("config");
1212         ret = git_config_early(fn, data, repo_config);
1213         if (repo_config)
1214                 free(repo_config);
1215         return ret;
1216 }
1217
1218 int git_config(config_fn_t fn, void *data)
1219 {
1220         return git_config_with_options(fn, data, NULL, NULL, 1);
1221 }
1222
1223 /*
1224  * Find all the stuff for git_config_set() below.
1225  */
1226
1227 #define MAX_MATCHES 512
1228
1229 static struct {
1230         int baselen;
1231         char *key;
1232         int do_not_match;
1233         regex_t *value_regex;
1234         int multi_replace;
1235         size_t offset[MAX_MATCHES];
1236         enum { START, SECTION_SEEN, SECTION_END_SEEN, KEY_SEEN } state;
1237         int seen;
1238 } store;
1239
1240 static int matches(const char *key, const char *value)
1241 {
1242         return !strcmp(key, store.key) &&
1243                 (store.value_regex == NULL ||
1244                  (store.do_not_match ^
1245                   !regexec(store.value_regex, value, 0, NULL, 0)));
1246 }
1247
1248 static int store_aux(const char *key, const char *value, void *cb)
1249 {
1250         const char *ep;
1251         size_t section_len;
1252
1253         switch (store.state) {
1254         case KEY_SEEN:
1255                 if (matches(key, value)) {
1256                         if (store.seen == 1 && store.multi_replace == 0) {
1257                                 warning("%s has multiple values", key);
1258                         } else if (store.seen >= MAX_MATCHES) {
1259                                 error("too many matches for %s", key);
1260                                 return 1;
1261                         }
1262
1263                         store.offset[store.seen] = cf->do_ftell(cf);
1264                         store.seen++;
1265                 }
1266                 break;
1267         case SECTION_SEEN:
1268                 /*
1269                  * What we are looking for is in store.key (both
1270                  * section and var), and its section part is baselen
1271                  * long.  We found key (again, both section and var).
1272                  * We would want to know if this key is in the same
1273                  * section as what we are looking for.  We already
1274                  * know we are in the same section as what should
1275                  * hold store.key.
1276                  */
1277                 ep = strrchr(key, '.');
1278                 section_len = ep - key;
1279
1280                 if ((section_len != store.baselen) ||
1281                     memcmp(key, store.key, section_len+1)) {
1282                         store.state = SECTION_END_SEEN;
1283                         break;
1284                 }
1285
1286                 /*
1287                  * Do not increment matches: this is no match, but we
1288                  * just made sure we are in the desired section.
1289                  */
1290                 store.offset[store.seen] = cf->do_ftell(cf);
1291                 /* fallthru */
1292         case SECTION_END_SEEN:
1293         case START:
1294                 if (matches(key, value)) {
1295                         store.offset[store.seen] = cf->do_ftell(cf);
1296                         store.state = KEY_SEEN;
1297                         store.seen++;
1298                 } else {
1299                         if (strrchr(key, '.') - key == store.baselen &&
1300                               !strncmp(key, store.key, store.baselen)) {
1301                                         store.state = SECTION_SEEN;
1302                                         store.offset[store.seen] = cf->do_ftell(cf);
1303                         }
1304                 }
1305         }
1306         return 0;
1307 }
1308
1309 static int write_error(const char *filename)
1310 {
1311         error("failed to write new configuration file %s", filename);
1312
1313         /* Same error code as "failed to rename". */
1314         return 4;
1315 }
1316
1317 static int store_write_section(int fd, const char *key)
1318 {
1319         const char *dot;
1320         int i, success;
1321         struct strbuf sb = STRBUF_INIT;
1322
1323         dot = memchr(key, '.', store.baselen);
1324         if (dot) {
1325                 strbuf_addf(&sb, "[%.*s \"", (int)(dot - key), key);
1326                 for (i = dot - key + 1; i < store.baselen; i++) {
1327                         if (key[i] == '"' || key[i] == '\\')
1328                                 strbuf_addch(&sb, '\\');
1329                         strbuf_addch(&sb, key[i]);
1330                 }
1331                 strbuf_addstr(&sb, "\"]\n");
1332         } else {
1333                 strbuf_addf(&sb, "[%.*s]\n", store.baselen, key);
1334         }
1335
1336         success = write_in_full(fd, sb.buf, sb.len) == sb.len;
1337         strbuf_release(&sb);
1338
1339         return success;
1340 }
1341
1342 static int store_write_pair(int fd, const char *key, const char *value)
1343 {
1344         int i, success;
1345         int length = strlen(key + store.baselen + 1);
1346         const char *quote = "";
1347         struct strbuf sb = STRBUF_INIT;
1348
1349         /*
1350          * Check to see if the value needs to be surrounded with a dq pair.
1351          * Note that problematic characters are always backslash-quoted; this
1352          * check is about not losing leading or trailing SP and strings that
1353          * follow beginning-of-comment characters (i.e. ';' and '#') by the
1354          * configuration parser.
1355          */
1356         if (value[0] == ' ')
1357                 quote = "\"";
1358         for (i = 0; value[i]; i++)
1359                 if (value[i] == ';' || value[i] == '#')
1360                         quote = "\"";
1361         if (i && value[i - 1] == ' ')
1362                 quote = "\"";
1363
1364         strbuf_addf(&sb, "\t%.*s = %s",
1365                     length, key + store.baselen + 1, quote);
1366
1367         for (i = 0; value[i]; i++)
1368                 switch (value[i]) {
1369                 case '\n':
1370                         strbuf_addstr(&sb, "\\n");
1371                         break;
1372                 case '\t':
1373                         strbuf_addstr(&sb, "\\t");
1374                         break;
1375                 case '"':
1376                 case '\\':
1377                         strbuf_addch(&sb, '\\');
1378                 default:
1379                         strbuf_addch(&sb, value[i]);
1380                         break;
1381                 }
1382         strbuf_addf(&sb, "%s\n", quote);
1383
1384         success = write_in_full(fd, sb.buf, sb.len) == sb.len;
1385         strbuf_release(&sb);
1386
1387         return success;
1388 }
1389
1390 static ssize_t find_beginning_of_line(const char *contents, size_t size,
1391         size_t offset_, int *found_bracket)
1392 {
1393         size_t equal_offset = size, bracket_offset = size;
1394         ssize_t offset;
1395
1396 contline:
1397         for (offset = offset_-2; offset > 0
1398                         && contents[offset] != '\n'; offset--)
1399                 switch (contents[offset]) {
1400                         case '=': equal_offset = offset; break;
1401                         case ']': bracket_offset = offset; break;
1402                 }
1403         if (offset > 0 && contents[offset-1] == '\\') {
1404                 offset_ = offset;
1405                 goto contline;
1406         }
1407         if (bracket_offset < equal_offset) {
1408                 *found_bracket = 1;
1409                 offset = bracket_offset+1;
1410         } else
1411                 offset++;
1412
1413         return offset;
1414 }
1415
1416 int git_config_set_in_file(const char *config_filename,
1417                         const char *key, const char *value)
1418 {
1419         return git_config_set_multivar_in_file(config_filename, key, value, NULL, 0);
1420 }
1421
1422 int git_config_set(const char *key, const char *value)
1423 {
1424         return git_config_set_multivar(key, value, NULL, 0);
1425 }
1426
1427 /*
1428  * Auxiliary function to sanity-check and split the key into the section
1429  * identifier and variable name.
1430  *
1431  * Returns 0 on success, -1 when there is an invalid character in the key and
1432  * -2 if there is no section name in the key.
1433  *
1434  * store_key - pointer to char* which will hold a copy of the key with
1435  *             lowercase section and variable name
1436  * baselen - pointer to int which will hold the length of the
1437  *           section + subsection part, can be NULL
1438  */
1439 int git_config_parse_key(const char *key, char **store_key, int *baselen_)
1440 {
1441         int i, dot, baselen;
1442         const char *last_dot = strrchr(key, '.');
1443
1444         /*
1445          * Since "key" actually contains the section name and the real
1446          * key name separated by a dot, we have to know where the dot is.
1447          */
1448
1449         if (last_dot == NULL || last_dot == key) {
1450                 error("key does not contain a section: %s", key);
1451                 return -CONFIG_NO_SECTION_OR_NAME;
1452         }
1453
1454         if (!last_dot[1]) {
1455                 error("key does not contain variable name: %s", key);
1456                 return -CONFIG_NO_SECTION_OR_NAME;
1457         }
1458
1459         baselen = last_dot - key;
1460         if (baselen_)
1461                 *baselen_ = baselen;
1462
1463         /*
1464          * Validate the key and while at it, lower case it for matching.
1465          */
1466         *store_key = xmalloc(strlen(key) + 1);
1467
1468         dot = 0;
1469         for (i = 0; key[i]; i++) {
1470                 unsigned char c = key[i];
1471                 if (c == '.')
1472                         dot = 1;
1473                 /* Leave the extended basename untouched.. */
1474                 if (!dot || i > baselen) {
1475                         if (!iskeychar(c) ||
1476                             (i == baselen + 1 && !isalpha(c))) {
1477                                 error("invalid key: %s", key);
1478                                 goto out_free_ret_1;
1479                         }
1480                         c = tolower(c);
1481                 } else if (c == '\n') {
1482                         error("invalid key (newline): %s", key);
1483                         goto out_free_ret_1;
1484                 }
1485                 (*store_key)[i] = c;
1486         }
1487         (*store_key)[i] = 0;
1488
1489         return 0;
1490
1491 out_free_ret_1:
1492         free(*store_key);
1493         *store_key = NULL;
1494         return -CONFIG_INVALID_KEY;
1495 }
1496
1497 /*
1498  * If value==NULL, unset in (remove from) config,
1499  * if value_regex!=NULL, disregard key/value pairs where value does not match.
1500  * if multi_replace==0, nothing, or only one matching key/value is replaced,
1501  *     else all matching key/values (regardless how many) are removed,
1502  *     before the new pair is written.
1503  *
1504  * Returns 0 on success.
1505  *
1506  * This function does this:
1507  *
1508  * - it locks the config file by creating ".git/config.lock"
1509  *
1510  * - it then parses the config using store_aux() as validator to find
1511  *   the position on the key/value pair to replace. If it is to be unset,
1512  *   it must be found exactly once.
1513  *
1514  * - the config file is mmap()ed and the part before the match (if any) is
1515  *   written to the lock file, then the changed part and the rest.
1516  *
1517  * - the config file is removed and the lock file rename()d to it.
1518  *
1519  */
1520 int git_config_set_multivar_in_file(const char *config_filename,
1521                                 const char *key, const char *value,
1522                                 const char *value_regex, int multi_replace)
1523 {
1524         int fd = -1, in_fd;
1525         int ret;
1526         struct lock_file *lock = NULL;
1527         char *filename_buf = NULL;
1528
1529         /* parse-key returns negative; flip the sign to feed exit(3) */
1530         ret = 0 - git_config_parse_key(key, &store.key, &store.baselen);
1531         if (ret)
1532                 goto out_free;
1533
1534         store.multi_replace = multi_replace;
1535
1536         if (!config_filename)
1537                 config_filename = filename_buf = git_pathdup("config");
1538
1539         /*
1540          * The lock serves a purpose in addition to locking: the new
1541          * contents of .git/config will be written into it.
1542          */
1543         lock = xcalloc(sizeof(struct lock_file), 1);
1544         fd = hold_lock_file_for_update(lock, config_filename, 0);
1545         if (fd < 0) {
1546                 error("could not lock config file %s: %s", config_filename, strerror(errno));
1547                 free(store.key);
1548                 ret = CONFIG_NO_LOCK;
1549                 goto out_free;
1550         }
1551
1552         /*
1553          * If .git/config does not exist yet, write a minimal version.
1554          */
1555         in_fd = open(config_filename, O_RDONLY);
1556         if ( in_fd < 0 ) {
1557                 free(store.key);
1558
1559                 if ( ENOENT != errno ) {
1560                         error("opening %s: %s", config_filename,
1561                               strerror(errno));
1562                         ret = CONFIG_INVALID_FILE; /* same as "invalid config file" */
1563                         goto out_free;
1564                 }
1565                 /* if nothing to unset, error out */
1566                 if (value == NULL) {
1567                         ret = CONFIG_NOTHING_SET;
1568                         goto out_free;
1569                 }
1570
1571                 store.key = (char *)key;
1572                 if (!store_write_section(fd, key) ||
1573                     !store_write_pair(fd, key, value))
1574                         goto write_err_out;
1575         } else {
1576                 struct stat st;
1577                 char *contents;
1578                 size_t contents_sz, copy_begin, copy_end;
1579                 int i, new_line = 0;
1580
1581                 if (value_regex == NULL)
1582                         store.value_regex = NULL;
1583                 else {
1584                         if (value_regex[0] == '!') {
1585                                 store.do_not_match = 1;
1586                                 value_regex++;
1587                         } else
1588                                 store.do_not_match = 0;
1589
1590                         store.value_regex = (regex_t*)xmalloc(sizeof(regex_t));
1591                         if (regcomp(store.value_regex, value_regex,
1592                                         REG_EXTENDED)) {
1593                                 error("invalid pattern: %s", value_regex);
1594                                 free(store.value_regex);
1595                                 ret = CONFIG_INVALID_PATTERN;
1596                                 goto out_free;
1597                         }
1598                 }
1599
1600                 store.offset[0] = 0;
1601                 store.state = START;
1602                 store.seen = 0;
1603
1604                 /*
1605                  * After this, store.offset will contain the *end* offset
1606                  * of the last match, or remain at 0 if no match was found.
1607                  * As a side effect, we make sure to transform only a valid
1608                  * existing config file.
1609                  */
1610                 if (git_config_from_file(store_aux, config_filename, NULL)) {
1611                         error("invalid config file %s", config_filename);
1612                         free(store.key);
1613                         if (store.value_regex != NULL) {
1614                                 regfree(store.value_regex);
1615                                 free(store.value_regex);
1616                         }
1617                         ret = CONFIG_INVALID_FILE;
1618                         goto out_free;
1619                 }
1620
1621                 free(store.key);
1622                 if (store.value_regex != NULL) {
1623                         regfree(store.value_regex);
1624                         free(store.value_regex);
1625                 }
1626
1627                 /* if nothing to unset, or too many matches, error out */
1628                 if ((store.seen == 0 && value == NULL) ||
1629                                 (store.seen > 1 && multi_replace == 0)) {
1630                         ret = CONFIG_NOTHING_SET;
1631                         goto out_free;
1632                 }
1633
1634                 fstat(in_fd, &st);
1635                 contents_sz = xsize_t(st.st_size);
1636                 contents = xmmap(NULL, contents_sz, PROT_READ,
1637                         MAP_PRIVATE, in_fd, 0);
1638                 close(in_fd);
1639
1640                 if (store.seen == 0)
1641                         store.seen = 1;
1642
1643                 for (i = 0, copy_begin = 0; i < store.seen; i++) {
1644                         if (store.offset[i] == 0) {
1645                                 store.offset[i] = copy_end = contents_sz;
1646                         } else if (store.state != KEY_SEEN) {
1647                                 copy_end = store.offset[i];
1648                         } else
1649                                 copy_end = find_beginning_of_line(
1650                                         contents, contents_sz,
1651                                         store.offset[i]-2, &new_line);
1652
1653                         if (copy_end > 0 && contents[copy_end-1] != '\n')
1654                                 new_line = 1;
1655
1656                         /* write the first part of the config */
1657                         if (copy_end > copy_begin) {
1658                                 if (write_in_full(fd, contents + copy_begin,
1659                                                   copy_end - copy_begin) <
1660                                     copy_end - copy_begin)
1661                                         goto write_err_out;
1662                                 if (new_line &&
1663                                     write_str_in_full(fd, "\n") != 1)
1664                                         goto write_err_out;
1665                         }
1666                         copy_begin = store.offset[i];
1667                 }
1668
1669                 /* write the pair (value == NULL means unset) */
1670                 if (value != NULL) {
1671                         if (store.state == START) {
1672                                 if (!store_write_section(fd, key))
1673                                         goto write_err_out;
1674                         }
1675                         if (!store_write_pair(fd, key, value))
1676                                 goto write_err_out;
1677                 }
1678
1679                 /* write the rest of the config */
1680                 if (copy_begin < contents_sz)
1681                         if (write_in_full(fd, contents + copy_begin,
1682                                           contents_sz - copy_begin) <
1683                             contents_sz - copy_begin)
1684                                 goto write_err_out;
1685
1686                 munmap(contents, contents_sz);
1687         }
1688
1689         if (commit_lock_file(lock) < 0) {
1690                 error("could not commit config file %s", config_filename);
1691                 ret = CONFIG_NO_WRITE;
1692                 goto out_free;
1693         }
1694
1695         /*
1696          * lock is committed, so don't try to roll it back below.
1697          * NOTE: Since lockfile.c keeps a linked list of all created
1698          * lock_file structures, it isn't safe to free(lock).  It's
1699          * better to just leave it hanging around.
1700          */
1701         lock = NULL;
1702         ret = 0;
1703
1704 out_free:
1705         if (lock)
1706                 rollback_lock_file(lock);
1707         free(filename_buf);
1708         return ret;
1709
1710 write_err_out:
1711         ret = write_error(lock->filename);
1712         goto out_free;
1713
1714 }
1715
1716 int git_config_set_multivar(const char *key, const char *value,
1717                         const char *value_regex, int multi_replace)
1718 {
1719         return git_config_set_multivar_in_file(NULL, key, value, value_regex,
1720                                                multi_replace);
1721 }
1722
1723 static int section_name_match (const char *buf, const char *name)
1724 {
1725         int i = 0, j = 0, dot = 0;
1726         if (buf[i] != '[')
1727                 return 0;
1728         for (i = 1; buf[i] && buf[i] != ']'; i++) {
1729                 if (!dot && isspace(buf[i])) {
1730                         dot = 1;
1731                         if (name[j++] != '.')
1732                                 break;
1733                         for (i++; isspace(buf[i]); i++)
1734                                 ; /* do nothing */
1735                         if (buf[i] != '"')
1736                                 break;
1737                         continue;
1738                 }
1739                 if (buf[i] == '\\' && dot)
1740                         i++;
1741                 else if (buf[i] == '"' && dot) {
1742                         for (i++; isspace(buf[i]); i++)
1743                                 ; /* do_nothing */
1744                         break;
1745                 }
1746                 if (buf[i] != name[j++])
1747                         break;
1748         }
1749         if (buf[i] == ']' && name[j] == 0) {
1750                 /*
1751                  * We match, now just find the right length offset by
1752                  * gobbling up any whitespace after it, as well
1753                  */
1754                 i++;
1755                 for (; buf[i] && isspace(buf[i]); i++)
1756                         ; /* do nothing */
1757                 return i;
1758         }
1759         return 0;
1760 }
1761
1762 static int section_name_is_ok(const char *name)
1763 {
1764         /* Empty section names are bogus. */
1765         if (!*name)
1766                 return 0;
1767
1768         /*
1769          * Before a dot, we must be alphanumeric or dash. After the first dot,
1770          * anything goes, so we can stop checking.
1771          */
1772         for (; *name && *name != '.'; name++)
1773                 if (*name != '-' && !isalnum(*name))
1774                         return 0;
1775         return 1;
1776 }
1777
1778 /* if new_name == NULL, the section is removed instead */
1779 int git_config_rename_section_in_file(const char *config_filename,
1780                                       const char *old_name, const char *new_name)
1781 {
1782         int ret = 0, remove = 0;
1783         char *filename_buf = NULL;
1784         struct lock_file *lock;
1785         int out_fd;
1786         char buf[1024];
1787         FILE *config_file;
1788
1789         if (new_name && !section_name_is_ok(new_name)) {
1790                 ret = error("invalid section name: %s", new_name);
1791                 goto out;
1792         }
1793
1794         if (!config_filename)
1795                 config_filename = filename_buf = git_pathdup("config");
1796
1797         lock = xcalloc(sizeof(struct lock_file), 1);
1798         out_fd = hold_lock_file_for_update(lock, config_filename, 0);
1799         if (out_fd < 0) {
1800                 ret = error("could not lock config file %s", config_filename);
1801                 goto out;
1802         }
1803
1804         if (!(config_file = fopen(config_filename, "rb"))) {
1805                 /* no config file means nothing to rename, no error */
1806                 goto unlock_and_out;
1807         }
1808
1809         while (fgets(buf, sizeof(buf), config_file)) {
1810                 int i;
1811                 int length;
1812                 char *output = buf;
1813                 for (i = 0; buf[i] && isspace(buf[i]); i++)
1814                         ; /* do nothing */
1815                 if (buf[i] == '[') {
1816                         /* it's a section */
1817                         int offset = section_name_match(&buf[i], old_name);
1818                         if (offset > 0) {
1819                                 ret++;
1820                                 if (new_name == NULL) {
1821                                         remove = 1;
1822                                         continue;
1823                                 }
1824                                 store.baselen = strlen(new_name);
1825                                 if (!store_write_section(out_fd, new_name)) {
1826                                         ret = write_error(lock->filename);
1827                                         goto out;
1828                                 }
1829                                 /*
1830                                  * We wrote out the new section, with
1831                                  * a newline, now skip the old
1832                                  * section's length
1833                                  */
1834                                 output += offset + i;
1835                                 if (strlen(output) > 0) {
1836                                         /*
1837                                          * More content means there's
1838                                          * a declaration to put on the
1839                                          * next line; indent with a
1840                                          * tab
1841                                          */
1842                                         output -= 1;
1843                                         output[0] = '\t';
1844                                 }
1845                         }
1846                         remove = 0;
1847                 }
1848                 if (remove)
1849                         continue;
1850                 length = strlen(output);
1851                 if (write_in_full(out_fd, output, length) != length) {
1852                         ret = write_error(lock->filename);
1853                         goto out;
1854                 }
1855         }
1856         fclose(config_file);
1857 unlock_and_out:
1858         if (commit_lock_file(lock) < 0)
1859                 ret = error("could not commit config file %s", config_filename);
1860 out:
1861         free(filename_buf);
1862         return ret;
1863 }
1864
1865 int git_config_rename_section(const char *old_name, const char *new_name)
1866 {
1867         return git_config_rename_section_in_file(NULL, old_name, new_name);
1868 }
1869
1870 /*
1871  * Call this to report error for your variable that should not
1872  * get a boolean value (i.e. "[my] var" means "true").
1873  */
1874 #undef config_error_nonbool
1875 int config_error_nonbool(const char *var)
1876 {
1877         return error("Missing value for '%s'", var);
1878 }
1879
1880 int parse_config_key(const char *var,
1881                      const char *section,
1882                      const char **subsection, int *subsection_len,
1883                      const char **key)
1884 {
1885         int section_len = strlen(section);
1886         const char *dot;
1887
1888         /* Does it start with "section." ? */
1889         if (prefixcmp(var, section) || var[section_len] != '.')
1890                 return -1;
1891
1892         /*
1893          * Find the key; we don't know yet if we have a subsection, but we must
1894          * parse backwards from the end, since the subsection may have dots in
1895          * it, too.
1896          */
1897         dot = strrchr(var, '.');
1898         *key = dot + 1;
1899
1900         /* Did we have a subsection at all? */
1901         if (dot == var + section_len) {
1902                 *subsection = NULL;
1903                 *subsection_len = 0;
1904         }
1905         else {
1906                 *subsection = var + section_len + 1;
1907                 *subsection_len = dot - *subsection;
1908         }
1909
1910         return 0;
1911 }