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_long(const char *value, long *ret)
 472 {
 473         if (value && *value) {
 474                 char *end;
 475                 intmax_t val;
 476                 uintmax_t uval;
 477                 uintmax_t factor = 1;
 478
 479                 errno = 0;
 480                 val = strtoimax(value, &end, 0);
 481                 if (errno == ERANGE)
 482                         return 0;
 483                 if (!parse_unit_factor(end, &factor))
 484                         return 0;
 485                 uval = abs(val);
 486                 uval *= factor;
 487                 if ((uval > maximum_signed_value_of_type(long)) ||
 488                     (abs(val) > uval))
 489                         return 0;
 490                 val *= factor;
 491                 *ret = val;
 492                 return 1;
 493         }
 494         return 0;
 495 }
 496
 497 int git_parse_ulong(const char *value, unsigned long *ret)
 498 {
 499         if (value && *value) {
 500                 char *end;
 501                 uintmax_t val;
 502                 uintmax_t oldval;
 503
 504                 errno = 0;
 505                 val = strtoumax(value, &end, 0);
 506                 if (errno == ERANGE)
 507                         return 0;
 508                 oldval = val;
 509                 if (!parse_unit_factor(end, &val))
 510                         return 0;
 511                 if ((val > maximum_unsigned_value_of_type(long)) ||
 512                     (oldval > val))
 513                         return 0;
 514                 *ret = val;
 515                 return 1;
 516         }
 517         return 0;
 518 }
 519
 520 static void die_bad_config(const char *name)
 521 {
 522         if (cf && cf->name)
 523                 die("bad config value for '%s' in %s", name, cf->name);
 524         die("bad config value for '%s'", name);
 525 }
 526
 527 int git_config_int(const char *name, const char *value)
 528 {
 529         long ret = 0;
 530         if (!git_parse_long(value, &ret))
 531                 die_bad_config(name);
 532         return ret;
 533 }
 534
 535 unsigned long git_config_ulong(const char *name, const char *value)
 536 {
 537         unsigned long ret;
 538         if (!git_parse_ulong(value, &ret))
 539                 die_bad_config(name);
 540         return ret;
 541 }
 542
 543 static int git_config_maybe_bool_text(const char *name, const char *value)
 544 {
 545         if (!value)
 546                 return 1;
 547         if (!*value)
 548                 return 0;
 549         if (!strcasecmp(value, "true")
 550             || !strcasecmp(value, "yes")
 551             || !strcasecmp(value, "on"))
 552                 return 1;
 553         if (!strcasecmp(value, "false")
 554             || !strcasecmp(value, "no")
 555             || !strcasecmp(value, "off"))
 556                 return 0;
 557         return -1;
 558 }
 559
 560 int git_config_maybe_bool(const char *name, const char *value)
 561 {
 562         long v = git_config_maybe_bool_text(name, value);
 563         if (0 <= v)
 564                 return v;
 565         if (git_parse_long(value, &v))
 566                 return !!v;
 567         return -1;
 568 }
 569
 570 int git_config_bool_or_int(const char *name, const char *value, int *is_bool)
 571 {
 572         int v = git_config_maybe_bool_text(name, value);
 573         if (0 <= v) {
 574                 *is_bool = 1;
 575                 return v;
 576         }
 577         *is_bool = 0;
 578         return git_config_int(name, value);
 579 }
 580
 581 int git_config_bool(const char *name, const char *value)
 582 {
 583         int discard;
 584         return !!git_config_bool_or_int(name, value, &discard);
 585 }
 586
 587 int git_config_string(const char **dest, const char *var, const char *value)
 588 {
 589         if (!value)
 590                 return config_error_nonbool(var);
 591         *dest = xstrdup(value);
 592         return 0;
 593 }
 594
 595 int git_config_pathname(const char **dest, const char *var, const char *value)
 596 {
 597         if (!value)
 598                 return config_error_nonbool(var);
 599         *dest = expand_user_path(value);
 600         if (!*dest)
 601                 die("Failed to expand user dir in: '%s'", value);
 602         return 0;
 603 }
 604
 605 static int git_default_core_config(const char *var, const char *value)
 606 {
 607         /* This needs a better name */
 608         if (!strcmp(var, "core.filemode")) {
 609                 trust_executable_bit = git_config_bool(var, value);
 610                 return 0;
 611         }
 612         if (!strcmp(var, "core.trustctime")) {
 613                 trust_ctime = git_config_bool(var, value);
 614                 return 0;
 615         }
 616         if (!strcmp(var, "core.statinfo") ||
 617             !strcmp(var, "core.checkstat")) {
 618                 /*
 619                  * NEEDSWORK: statinfo was a typo in v1.8.2 that has
 620                  * never been advertised.  we will remove it at Git
 621                  * 2.0 boundary.
 622                  */
 623                 if (!strcmp(var, "core.statinfo")) {
 624                         static int warned;
 625                         if (!warned++) {
 626                                 warning("'core.statinfo' will be removed in Git 2.0; "
 627                                         "use 'core.checkstat' instead.");
 628                         }
 629                 }
 630                 if (!strcasecmp(value, "default"))
 631                         check_stat = 1;
 632                 else if (!strcasecmp(value, "minimal"))
 633                         check_stat = 0;
 634         }
 635
 636         if (!strcmp(var, "core.quotepath")) {
 637                 quote_path_fully = git_config_bool(var, value);
 638                 return 0;
 639         }
 640
 641         if (!strcmp(var, "core.symlinks")) {
 642                 has_symlinks = git_config_bool(var, value);
 643                 return 0;
 644         }
 645
 646         if (!strcmp(var, "core.ignorecase")) {
 647                 ignore_case = git_config_bool(var, value);
 648                 return 0;
 649         }
 650
 651         if (!strcmp(var, "core.attributesfile"))
 652                 return git_config_pathname(&git_attributes_file, var, value);
 653
 654         if (!strcmp(var, "core.bare")) {
 655                 is_bare_repository_cfg = git_config_bool(var, value);
 656                 return 0;
 657         }
 658
 659         if (!strcmp(var, "core.ignorestat")) {
 660                 assume_unchanged = git_config_bool(var, value);
 661                 return 0;
 662         }
 663
 664         if (!strcmp(var, "core.prefersymlinkrefs")) {
 665                 prefer_symlink_refs = git_config_bool(var, value);
 666                 return 0;
 667         }
 668
 669         if (!strcmp(var, "core.logallrefupdates")) {
 670                 log_all_ref_updates = git_config_bool(var, value);
 671                 return 0;
 672         }
 673
 674         if (!strcmp(var, "core.warnambiguousrefs")) {
 675                 warn_ambiguous_refs = git_config_bool(var, value);
 676                 return 0;
 677         }
 678
 679         if (!strcmp(var, "core.abbrev")) {
 680                 int abbrev = git_config_int(var, value);
 681                 if (abbrev < minimum_abbrev || abbrev > 40)
 682                         return -1;
 683                 default_abbrev = abbrev;
 684                 return 0;
 685         }
 686
 687         if (!strcmp(var, "core.loosecompression")) {
 688                 int level = git_config_int(var, value);
 689                 if (level == -1)
 690                         level = Z_DEFAULT_COMPRESSION;
 691                 else if (level < 0 || level > Z_BEST_COMPRESSION)
 692                         die("bad zlib compression level %d", level);
 693                 zlib_compression_level = level;
 694                 zlib_compression_seen = 1;
 695                 return 0;
 696         }
 697
 698         if (!strcmp(var, "core.compression")) {
 699                 int level = git_config_int(var, value);
 700                 if (level == -1)
 701                         level = Z_DEFAULT_COMPRESSION;
 702                 else if (level < 0 || level > Z_BEST_COMPRESSION)
 703                         die("bad zlib compression level %d", level);
 704                 core_compression_level = level;
 705                 core_compression_seen = 1;
 706                 if (!zlib_compression_seen)
 707                         zlib_compression_level = level;
 708                 return 0;
 709         }
 710
 711         if (!strcmp(var, "core.packedgitwindowsize")) {
 712                 int pgsz_x2 = getpagesize() * 2;
 713                 packed_git_window_size = git_config_ulong(var, value);
 714
 715                 /* This value must be multiple of (pagesize * 2) */
 716                 packed_git_window_size /= pgsz_x2;
 717                 if (packed_git_window_size < 1)
 718                         packed_git_window_size = 1;
 719                 packed_git_window_size *= pgsz_x2;
 720                 return 0;
 721         }
 722
 723         if (!strcmp(var, "core.bigfilethreshold")) {
 724                 big_file_threshold = git_config_ulong(var, value);
 725                 return 0;
 726         }
 727
 728         if (!strcmp(var, "core.packedgitlimit")) {
 729                 packed_git_limit = git_config_ulong(var, value);
 730                 return 0;
 731         }
 732
 733         if (!strcmp(var, "core.deltabasecachelimit")) {
 734                 delta_base_cache_limit = git_config_ulong(var, value);
 735                 return 0;
 736         }
 737
 738         if (!strcmp(var, "core.autocrlf")) {
 739                 if (value && !strcasecmp(value, "input")) {
 740                         if (core_eol == EOL_CRLF)
 741                                 return error("core.autocrlf=input conflicts with core.eol=crlf");
 742                         auto_crlf = AUTO_CRLF_INPUT;
 743                         return 0;
 744                 }
 745                 auto_crlf = git_config_bool(var, value);
 746                 return 0;
 747         }
 748
 749         if (!strcmp(var, "core.safecrlf")) {
 750                 if (value && !strcasecmp(value, "warn")) {
 751                         safe_crlf = SAFE_CRLF_WARN;
 752                         return 0;
 753                 }
 754                 safe_crlf = git_config_bool(var, value);
 755                 return 0;
 756         }
 757
 758         if (!strcmp(var, "core.eol")) {
 759                 if (value && !strcasecmp(value, "lf"))
 760                         core_eol = EOL_LF;
 761                 else if (value && !strcasecmp(value, "crlf"))
 762                         core_eol = EOL_CRLF;
 763                 else if (value && !strcasecmp(value, "native"))
 764                         core_eol = EOL_NATIVE;
 765                 else
 766                         core_eol = EOL_UNSET;
 767                 if (core_eol == EOL_CRLF && auto_crlf == AUTO_CRLF_INPUT)
 768                         return error("core.autocrlf=input conflicts with core.eol=crlf");
 769                 return 0;
 770         }
 771
 772         if (!strcmp(var, "core.notesref")) {
 773                 notes_ref_name = xstrdup(value);
 774                 return 0;
 775         }
 776
 777         if (!strcmp(var, "core.pager"))
 778                 return git_config_string(&pager_program, var, value);
 779
 780         if (!strcmp(var, "core.editor"))
 781                 return git_config_string(&editor_program, var, value);
 782
 783         if (!strcmp(var, "core.commentchar")) {
 784                 const char *comment;
 785                 int ret = git_config_string(&comment, var, value);
 786                 if (!ret)
 787                         comment_line_char = comment[0];
 788                 return ret;
 789         }
 790
 791         if (!strcmp(var, "core.askpass"))
 792                 return git_config_string(&askpass_program, var, value);
 793
 794         if (!strcmp(var, "core.excludesfile"))
 795                 return git_config_pathname(&excludes_file, var, value);
 796
 797         if (!strcmp(var, "core.whitespace")) {
 798                 if (!value)
 799                         return config_error_nonbool(var);
 800                 whitespace_rule_cfg = parse_whitespace_rule(value);
 801                 return 0;
 802         }
 803
 804         if (!strcmp(var, "core.fsyncobjectfiles")) {
 805                 fsync_object_files = git_config_bool(var, value);
 806                 return 0;
 807         }
 808
 809         if (!strcmp(var, "core.preloadindex")) {
 810                 core_preload_index = git_config_bool(var, value);
 811                 return 0;
 812         }
 813
 814         if (!strcmp(var, "core.createobject")) {
 815                 if (!strcmp(value, "rename"))
 816                         object_creation_mode = OBJECT_CREATION_USES_RENAMES;
 817                 else if (!strcmp(value, "link"))
 818                         object_creation_mode = OBJECT_CREATION_USES_HARDLINKS;
 819                 else
 820                         die("Invalid mode for object creation: %s", value);
 821                 return 0;
 822         }
 823
 824         if (!strcmp(var, "core.sparsecheckout")) {
 825                 core_apply_sparse_checkout = git_config_bool(var, value);
 826                 return 0;
 827         }
 828
 829         if (!strcmp(var, "core.precomposeunicode")) {
 830                 precomposed_unicode = git_config_bool(var, value);
 831                 return 0;
 832         }
 833
 834         /* Add other config variables here and to Documentation/config.txt. */
 835         return 0;
 836 }
 837
 838 static int git_default_i18n_config(const char *var, const char *value)
 839 {
 840         if (!strcmp(var, "i18n.commitencoding"))
 841                 return git_config_string(&git_commit_encoding, var, value);
 842
 843         if (!strcmp(var, "i18n.logoutputencoding"))
 844                 return git_config_string(&git_log_output_encoding, var, value);
 845
 846         /* Add other config variables here and to Documentation/config.txt. */
 847         return 0;
 848 }
 849
 850 static int git_default_branch_config(const char *var, const char *value)
 851 {
 852         if (!strcmp(var, "branch.autosetupmerge")) {
 853                 if (value && !strcasecmp(value, "always")) {
 854                         git_branch_track = BRANCH_TRACK_ALWAYS;
 855                         return 0;
 856                 }
 857                 git_branch_track = git_config_bool(var, value);
 858                 return 0;
 859         }
 860         if (!strcmp(var, "branch.autosetuprebase")) {
 861                 if (!value)
 862                         return config_error_nonbool(var);
 863                 else if (!strcmp(value, "never"))
 864                         autorebase = AUTOREBASE_NEVER;
 865                 else if (!strcmp(value, "local"))
 866                         autorebase = AUTOREBASE_LOCAL;
 867                 else if (!strcmp(value, "remote"))
 868                         autorebase = AUTOREBASE_REMOTE;
 869                 else if (!strcmp(value, "always"))
 870                         autorebase = AUTOREBASE_ALWAYS;
 871                 else
 872                         return error("Malformed value for %s", var);
 873                 return 0;
 874         }
 875
 876         /* Add other config variables here and to Documentation/config.txt. */
 877         return 0;
 878 }
 879
 880 static int git_default_push_config(const char *var, const char *value)
 881 {
 882         if (!strcmp(var, "push.default")) {
 883                 if (!value)
 884                         return config_error_nonbool(var);
 885                 else if (!strcmp(value, "nothing"))
 886                         push_default = PUSH_DEFAULT_NOTHING;
 887                 else if (!strcmp(value, "matching"))
 888                         push_default = PUSH_DEFAULT_MATCHING;
 889                 else if (!strcmp(value, "simple"))
 890                         push_default = PUSH_DEFAULT_SIMPLE;
 891                 else if (!strcmp(value, "upstream"))
 892                         push_default = PUSH_DEFAULT_UPSTREAM;
 893                 else if (!strcmp(value, "tracking")) /* deprecated */
 894                         push_default = PUSH_DEFAULT_UPSTREAM;
 895                 else if (!strcmp(value, "current"))
 896                         push_default = PUSH_DEFAULT_CURRENT;
 897                 else {
 898                         error("Malformed value for %s: %s", var, value);
 899                         return error("Must be one of nothing, matching, simple, "
 900                                      "upstream or current.");
 901                 }
 902                 return 0;
 903         }
 904
 905         /* Add other config variables here and to Documentation/config.txt. */
 906         return 0;
 907 }
 908
 909 static int git_default_mailmap_config(const char *var, const char *value)
 910 {
 911         if (!strcmp(var, "mailmap.file"))
 912                 return git_config_string(&git_mailmap_file, var, value);
 913         if (!strcmp(var, "mailmap.blob"))
 914                 return git_config_string(&git_mailmap_blob, var, value);
 915
 916         /* Add other config variables here and to Documentation/config.txt. */
 917         return 0;
 918 }
 919
 920 int git_default_config(const char *var, const char *value, void *dummy)
 921 {
 922         if (!prefixcmp(var, "core."))
 923                 return git_default_core_config(var, value);
 924
 925         if (!prefixcmp(var, "user."))
 926                 return git_ident_config(var, value, dummy);
 927
 928         if (!prefixcmp(var, "i18n."))
 929                 return git_default_i18n_config(var, value);
 930
 931         if (!prefixcmp(var, "branch."))
 932                 return git_default_branch_config(var, value);
 933
 934         if (!prefixcmp(var, "push."))
 935                 return git_default_push_config(var, value);
 936
 937         if (!prefixcmp(var, "mailmap."))
 938                 return git_default_mailmap_config(var, value);
 939
 940         if (!prefixcmp(var, "advice."))
 941                 return git_default_advice_config(var, value);
 942
 943         if (!strcmp(var, "pager.color") || !strcmp(var, "color.pager")) {
 944                 pager_use_color = git_config_bool(var,value);
 945                 return 0;
 946         }
 947
 948         if (!strcmp(var, "pack.packsizelimit")) {
 949                 pack_size_limit_cfg = git_config_ulong(var, value);
 950                 return 0;
 951         }
 952         /* Add other config variables here and to Documentation/config.txt. */
 953         return 0;
 954 }
 955
 956 /*
 957  * All source specific fields in the union, die_on_error, name and the callbacks
 958  * fgetc, ungetc, ftell of top need to be initialized before calling
 959  * this function.
 960  */
 961 static int do_config_from(struct config_source *top, config_fn_t fn, void *data)
 962 {
 963         int ret;
 964
 965         /* push config-file parsing state stack */
 966         top->prev = cf;
 967         top->linenr = 1;
 968         top->eof = 0;
 969         strbuf_init(&top->value, 1024);
 970         strbuf_init(&top->var, 1024);
 971         cf = top;
 972
 973         ret = git_parse_source(fn, data);
 974
 975         /* pop config-file parsing state stack */
 976         strbuf_release(&top->value);
 977         strbuf_release(&top->var);
 978         cf = top->prev;
 979
 980         return ret;
 981 }
 982
 983 int git_config_from_file(config_fn_t fn, const char *filename, void *data)
 984 {
 985         int ret;
 986         FILE *f = fopen(filename, "r");
 987
 988         ret = -1;
 989         if (f) {
 990                 struct config_source top;
 991
 992                 top.u.file = f;
 993                 top.name = filename;
 994                 top.die_on_error = 1;
 995                 top.do_fgetc = config_file_fgetc;
 996                 top.do_ungetc = config_file_ungetc;
 997                 top.do_ftell = config_file_ftell;
 998
 999                 ret = do_config_from(&top, fn, data);
1000
1001                 fclose(f);
1002         }
1003         return ret;
1004 }
1005
1006 int git_config_from_buf(config_fn_t fn, const char *name, const char *buf,
1007                         size_t len, void *data)
1008 {
1009         struct config_source top;
1010
1011         top.u.buf.buf = buf;
1012         top.u.buf.len = len;
1013         top.u.buf.pos = 0;
1014         top.name = name;
1015         top.die_on_error = 0;
1016         top.do_fgetc = config_buf_fgetc;
1017         top.do_ungetc = config_buf_ungetc;
1018         top.do_ftell = config_buf_ftell;
1019
1020         return do_config_from(&top, fn, data);
1021 }
1022
1023 static int git_config_from_blob_sha1(config_fn_t fn,
1024                                      const char *name,
1025                                      const unsigned char *sha1,
1026                                      void *data)
1027 {
1028         enum object_type type;
1029         char *buf;
1030         unsigned long size;
1031         int ret;
1032
1033         buf = read_sha1_file(sha1, &type, &size);
1034         if (!buf)
1035                 return error("unable to load config blob object '%s'", name);
1036         if (type != OBJ_BLOB) {
1037                 free(buf);
1038                 return error("reference '%s' does not point to a blob", name);
1039         }
1040
1041         ret = git_config_from_buf(fn, name, buf, size, data);
1042         free(buf);
1043
1044         return ret;
1045 }
1046
1047 static int git_config_from_blob_ref(config_fn_t fn,
1048                                     const char *name,
1049                                     void *data)
1050 {
1051         unsigned char sha1[20];
1052
1053         if (get_sha1(name, sha1) < 0)
1054                 return error("unable to resolve config blob '%s'", name);
1055         return git_config_from_blob_sha1(fn, name, sha1, data);
1056 }
1057
1058 const char *git_etc_gitconfig(void)
1059 {
1060         static const char *system_wide;
1061         if (!system_wide)
1062                 system_wide = system_path(ETC_GITCONFIG);
1063         return system_wide;
1064 }
1065
1066 int git_env_bool(const char *k, int def)
1067 {
1068         const char *v = getenv(k);
1069         return v ? git_config_bool(k, v) : def;
1070 }
1071
1072 int git_config_system(void)
1073 {
1074         return !git_env_bool("GIT_CONFIG_NOSYSTEM", 0);
1075 }
1076
1077 int git_config_early(config_fn_t fn, void *data, const char *repo_config)
1078 {
1079         int ret = 0, found = 0;
1080         char *xdg_config = NULL;
1081         char *user_config = NULL;
1082
1083         home_config_paths(&user_config, &xdg_config, "config");
1084
1085         if (git_config_system() && !access_or_die(git_etc_gitconfig(), R_OK, 0)) {
1086                 ret += git_config_from_file(fn, git_etc_gitconfig(),
1087                                             data);
1088                 found += 1;
1089         }
1090
1091         if (xdg_config && !access_or_die(xdg_config, R_OK, ACCESS_EACCES_OK)) {
1092                 ret += git_config_from_file(fn, xdg_config, data);
1093                 found += 1;
1094         }
1095
1096         if (user_config && !access_or_die(user_config, R_OK, ACCESS_EACCES_OK)) {
1097                 ret += git_config_from_file(fn, user_config, data);
1098                 found += 1;
1099         }
1100
1101         if (repo_config && !access_or_die(repo_config, R_OK, 0)) {
1102                 ret += git_config_from_file(fn, repo_config, data);
1103                 found += 1;
1104         }
1105
1106         switch (git_config_from_parameters(fn, data)) {
1107         case -1: /* error */
1108                 die("unable to parse command-line config");
1109                 break;
1110         case 0: /* found nothing */
1111                 break;
1112         default: /* found at least one item */
1113                 found++;
1114                 break;
1115         }
1116
1117         free(xdg_config);
1118         free(user_config);
1119         return ret == 0 ? found : ret;
1120 }
1121
1122 int git_config_with_options(config_fn_t fn, void *data,
1123                             const char *filename,
1124                             const char *blob_ref,
1125                             int respect_includes)
1126 {
1127         char *repo_config = NULL;
1128         int ret;
1129         struct config_include_data inc = CONFIG_INCLUDE_INIT;
1130
1131         if (respect_includes) {
1132                 inc.fn = fn;
1133                 inc.data = data;
1134                 fn = git_config_include;
1135                 data = &inc;
1136         }
1137
1138         /*
1139          * If we have a specific filename, use it. Otherwise, follow the
1140          * regular lookup sequence.
1141          */
1142         if (filename)
1143                 return git_config_from_file(fn, filename, data);
1144         else if (blob_ref)
1145                 return git_config_from_blob_ref(fn, blob_ref, data);
1146
1147         repo_config = git_pathdup("config");
1148         ret = git_config_early(fn, data, repo_config);
1149         if (repo_config)
1150                 free(repo_config);
1151         return ret;
1152 }
1153
1154 int git_config(config_fn_t fn, void *data)
1155 {
1156         return git_config_with_options(fn, data, NULL, NULL, 1);
1157 }
1158
1159 /*
1160  * Find all the stuff for git_config_set() below.
1161  */
1162
1163 #define MAX_MATCHES 512
1164
1165 static struct {
1166         int baselen;
1167         char *key;
1168         int do_not_match;
1169         regex_t *value_regex;
1170         int multi_replace;
1171         size_t offset[MAX_MATCHES];
1172         enum { START, SECTION_SEEN, SECTION_END_SEEN, KEY_SEEN } state;
1173         int seen;
1174 } store;
1175
1176 static int matches(const char *key, const char *value)
1177 {
1178         return !strcmp(key, store.key) &&
1179                 (store.value_regex == NULL ||
1180                  (store.do_not_match ^
1181                   !regexec(store.value_regex, value, 0, NULL, 0)));
1182 }
1183
1184 static int store_aux(const char *key, const char *value, void *cb)
1185 {
1186         const char *ep;
1187         size_t section_len;
1188
1189         switch (store.state) {
1190         case KEY_SEEN:
1191                 if (matches(key, value)) {
1192                         if (store.seen == 1 && store.multi_replace == 0) {
1193                                 warning("%s has multiple values", key);
1194                         } else if (store.seen >= MAX_MATCHES) {
1195                                 error("too many matches for %s", key);
1196                                 return 1;
1197                         }
1198
1199                         store.offset[store.seen] = cf->do_ftell(cf);
1200                         store.seen++;
1201                 }
1202                 break;
1203         case SECTION_SEEN:
1204                 /*
1205                  * What we are looking for is in store.key (both
1206                  * section and var), and its section part is baselen
1207                  * long.  We found key (again, both section and var).
1208                  * We would want to know if this key is in the same
1209                  * section as what we are looking for.  We already
1210                  * know we are in the same section as what should
1211                  * hold store.key.
1212                  */
1213                 ep = strrchr(key, '.');
1214                 section_len = ep - key;
1215
1216                 if ((section_len != store.baselen) ||
1217                     memcmp(key, store.key, section_len+1)) {
1218                         store.state = SECTION_END_SEEN;
1219                         break;
1220                 }
1221
1222                 /*
1223                  * Do not increment matches: this is no match, but we
1224                  * just made sure we are in the desired section.
1225                  */
1226                 store.offset[store.seen] = cf->do_ftell(cf);
1227                 /* fallthru */
1228         case SECTION_END_SEEN:
1229         case START:
1230                 if (matches(key, value)) {
1231                         store.offset[store.seen] = cf->do_ftell(cf);
1232                         store.state = KEY_SEEN;
1233                         store.seen++;
1234                 } else {
1235                         if (strrchr(key, '.') - key == store.baselen &&
1236                               !strncmp(key, store.key, store.baselen)) {
1237                                         store.state = SECTION_SEEN;
1238                                         store.offset[store.seen] = cf->do_ftell(cf);
1239                         }
1240                 }
1241         }
1242         return 0;
1243 }
1244
1245 static int write_error(const char *filename)
1246 {
1247         error("failed to write new configuration file %s", filename);
1248
1249         /* Same error code as "failed to rename". */
1250         return 4;
1251 }
1252
1253 static int store_write_section(int fd, const char *key)
1254 {
1255         const char *dot;
1256         int i, success;
1257         struct strbuf sb = STRBUF_INIT;
1258
1259         dot = memchr(key, '.', store.baselen);
1260         if (dot) {
1261                 strbuf_addf(&sb, "[%.*s \"", (int)(dot - key), key);
1262                 for (i = dot - key + 1; i < store.baselen; i++) {
1263                         if (key[i] == '"' || key[i] == '\\')
1264                                 strbuf_addch(&sb, '\\');
1265                         strbuf_addch(&sb, key[i]);
1266                 }
1267                 strbuf_addstr(&sb, "\"]\n");
1268         } else {
1269                 strbuf_addf(&sb, "[%.*s]\n", store.baselen, key);
1270         }
1271
1272         success = write_in_full(fd, sb.buf, sb.len) == sb.len;
1273         strbuf_release(&sb);
1274
1275         return success;
1276 }
1277
1278 static int store_write_pair(int fd, const char *key, const char *value)
1279 {
1280         int i, success;
1281         int length = strlen(key + store.baselen + 1);
1282         const char *quote = "";
1283         struct strbuf sb = STRBUF_INIT;
1284
1285         /*
1286          * Check to see if the value needs to be surrounded with a dq pair.
1287          * Note that problematic characters are always backslash-quoted; this
1288          * check is about not losing leading or trailing SP and strings that
1289          * follow beginning-of-comment characters (i.e. ';' and '#') by the
1290          * configuration parser.
1291          */
1292         if (value[0] == ' ')
1293                 quote = "\"";
1294         for (i = 0; value[i]; i++)
1295                 if (value[i] == ';' || value[i] == '#')
1296                         quote = "\"";
1297         if (i && value[i - 1] == ' ')
1298                 quote = "\"";
1299
1300         strbuf_addf(&sb, "\t%.*s = %s",
1301                     length, key + store.baselen + 1, quote);
1302
1303         for (i = 0; value[i]; i++)
1304                 switch (value[i]) {
1305                 case '\n':
1306                         strbuf_addstr(&sb, "\\n");
1307                         break;
1308                 case '\t':
1309                         strbuf_addstr(&sb, "\\t");
1310                         break;
1311                 case '"':
1312                 case '\\':
1313                         strbuf_addch(&sb, '\\');
1314                 default:
1315                         strbuf_addch(&sb, value[i]);
1316                         break;
1317                 }
1318         strbuf_addf(&sb, "%s\n", quote);
1319
1320         success = write_in_full(fd, sb.buf, sb.len) == sb.len;
1321         strbuf_release(&sb);
1322
1323         return success;
1324 }
1325
1326 static ssize_t find_beginning_of_line(const char *contents, size_t size,
1327         size_t offset_, int *found_bracket)
1328 {
1329         size_t equal_offset = size, bracket_offset = size;
1330         ssize_t offset;
1331
1332 contline:
1333         for (offset = offset_-2; offset > 0
1334                         && contents[offset] != '\n'; offset--)
1335                 switch (contents[offset]) {
1336                         case '=': equal_offset = offset; break;
1337                         case ']': bracket_offset = offset; break;
1338                 }
1339         if (offset > 0 && contents[offset-1] == '\\') {
1340                 offset_ = offset;
1341                 goto contline;
1342         }
1343         if (bracket_offset < equal_offset) {
1344                 *found_bracket = 1;
1345                 offset = bracket_offset+1;
1346         } else
1347                 offset++;
1348
1349         return offset;
1350 }
1351
1352 int git_config_set_in_file(const char *config_filename,
1353                         const char *key, const char *value)
1354 {
1355         return git_config_set_multivar_in_file(config_filename, key, value, NULL, 0);
1356 }
1357
1358 int git_config_set(const char *key, const char *value)
1359 {
1360         return git_config_set_multivar(key, value, NULL, 0);
1361 }
1362
1363 /*
1364  * Auxiliary function to sanity-check and split the key into the section
1365  * identifier and variable name.
1366  *
1367  * Returns 0 on success, -1 when there is an invalid character in the key and
1368  * -2 if there is no section name in the key.
1369  *
1370  * store_key - pointer to char* which will hold a copy of the key with
1371  *             lowercase section and variable name
1372  * baselen - pointer to int which will hold the length of the
1373  *           section + subsection part, can be NULL
1374  */
1375 int git_config_parse_key(const char *key, char **store_key, int *baselen_)
1376 {
1377         int i, dot, baselen;
1378         const char *last_dot = strrchr(key, '.');
1379
1380         /*
1381          * Since "key" actually contains the section name and the real
1382          * key name separated by a dot, we have to know where the dot is.
1383          */
1384
1385         if (last_dot == NULL || last_dot == key) {
1386                 error("key does not contain a section: %s", key);
1387                 return -CONFIG_NO_SECTION_OR_NAME;
1388         }
1389
1390         if (!last_dot[1]) {
1391                 error("key does not contain variable name: %s", key);
1392                 return -CONFIG_NO_SECTION_OR_NAME;
1393         }
1394
1395         baselen = last_dot - key;
1396         if (baselen_)
1397                 *baselen_ = baselen;
1398
1399         /*
1400          * Validate the key and while at it, lower case it for matching.
1401          */
1402         *store_key = xmalloc(strlen(key) + 1);
1403
1404         dot = 0;
1405         for (i = 0; key[i]; i++) {
1406                 unsigned char c = key[i];
1407                 if (c == '.')
1408                         dot = 1;
1409                 /* Leave the extended basename untouched.. */
1410                 if (!dot || i > baselen) {
1411                         if (!iskeychar(c) ||
1412                             (i == baselen + 1 && !isalpha(c))) {
1413                                 error("invalid key: %s", key);
1414                                 goto out_free_ret_1;
1415                         }
1416                         c = tolower(c);
1417                 } else if (c == '\n') {
1418                         error("invalid key (newline): %s", key);
1419                         goto out_free_ret_1;
1420                 }
1421                 (*store_key)[i] = c;
1422         }
1423         (*store_key)[i] = 0;
1424
1425         return 0;
1426
1427 out_free_ret_1:
1428         free(*store_key);
1429         *store_key = NULL;
1430         return -CONFIG_INVALID_KEY;
1431 }
1432
1433 /*
1434  * If value==NULL, unset in (remove from) config,
1435  * if value_regex!=NULL, disregard key/value pairs where value does not match.
1436  * if multi_replace==0, nothing, or only one matching key/value is replaced,
1437  *     else all matching key/values (regardless how many) are removed,
1438  *     before the new pair is written.
1439  *
1440  * Returns 0 on success.
1441  *
1442  * This function does this:
1443  *
1444  * - it locks the config file by creating ".git/config.lock"
1445  *
1446  * - it then parses the config using store_aux() as validator to find
1447  *   the position on the key/value pair to replace. If it is to be unset,
1448  *   it must be found exactly once.
1449  *
1450  * - the config file is mmap()ed and the part before the match (if any) is
1451  *   written to the lock file, then the changed part and the rest.
1452  *
1453  * - the config file is removed and the lock file rename()d to it.
1454  *
1455  */
1456 int git_config_set_multivar_in_file(const char *config_filename,
1457                                 const char *key, const char *value,
1458                                 const char *value_regex, int multi_replace)
1459 {
1460         int fd = -1, in_fd;
1461         int ret;
1462         struct lock_file *lock = NULL;
1463         char *filename_buf = NULL;
1464
1465         /* parse-key returns negative; flip the sign to feed exit(3) */
1466         ret = 0 - git_config_parse_key(key, &store.key, &store.baselen);
1467         if (ret)
1468                 goto out_free;
1469
1470         store.multi_replace = multi_replace;
1471
1472         if (!config_filename)
1473                 config_filename = filename_buf = git_pathdup("config");
1474
1475         /*
1476          * The lock serves a purpose in addition to locking: the new
1477          * contents of .git/config will be written into it.
1478          */
1479         lock = xcalloc(sizeof(struct lock_file), 1);
1480         fd = hold_lock_file_for_update(lock, config_filename, 0);
1481         if (fd < 0) {
1482                 error("could not lock config file %s: %s", config_filename, strerror(errno));
1483                 free(store.key);
1484                 ret = CONFIG_NO_LOCK;
1485                 goto out_free;
1486         }
1487
1488         /*
1489          * If .git/config does not exist yet, write a minimal version.
1490          */
1491         in_fd = open(config_filename, O_RDONLY);
1492         if ( in_fd < 0 ) {
1493                 free(store.key);
1494
1495                 if ( ENOENT != errno ) {
1496                         error("opening %s: %s", config_filename,
1497                               strerror(errno));
1498                         ret = CONFIG_INVALID_FILE; /* same as "invalid config file" */
1499                         goto out_free;
1500                 }
1501                 /* if nothing to unset, error out */
1502                 if (value == NULL) {
1503                         ret = CONFIG_NOTHING_SET;
1504                         goto out_free;
1505                 }
1506
1507                 store.key = (char *)key;
1508                 if (!store_write_section(fd, key) ||
1509                     !store_write_pair(fd, key, value))
1510                         goto write_err_out;
1511         } else {
1512                 struct stat st;
1513                 char *contents;
1514                 size_t contents_sz, copy_begin, copy_end;
1515                 int i, new_line = 0;
1516
1517                 if (value_regex == NULL)
1518                         store.value_regex = NULL;
1519                 else {
1520                         if (value_regex[0] == '!') {
1521                                 store.do_not_match = 1;
1522                                 value_regex++;
1523                         } else
1524                                 store.do_not_match = 0;
1525
1526                         store.value_regex = (regex_t*)xmalloc(sizeof(regex_t));
1527                         if (regcomp(store.value_regex, value_regex,
1528                                         REG_EXTENDED)) {
1529                                 error("invalid pattern: %s", value_regex);
1530                                 free(store.value_regex);
1531                                 ret = CONFIG_INVALID_PATTERN;
1532                                 goto out_free;
1533                         }
1534                 }
1535
1536                 store.offset[0] = 0;
1537                 store.state = START;
1538                 store.seen = 0;
1539
1540                 /*
1541                  * After this, store.offset will contain the *end* offset
1542                  * of the last match, or remain at 0 if no match was found.
1543                  * As a side effect, we make sure to transform only a valid
1544                  * existing config file.
1545                  */
1546                 if (git_config_from_file(store_aux, config_filename, NULL)) {
1547                         error("invalid config file %s", config_filename);
1548                         free(store.key);
1549                         if (store.value_regex != NULL) {
1550                                 regfree(store.value_regex);
1551                                 free(store.value_regex);
1552                         }
1553                         ret = CONFIG_INVALID_FILE;
1554                         goto out_free;
1555                 }
1556
1557                 free(store.key);
1558                 if (store.value_regex != NULL) {
1559                         regfree(store.value_regex);
1560                         free(store.value_regex);
1561                 }
1562
1563                 /* if nothing to unset, or too many matches, error out */
1564                 if ((store.seen == 0 && value == NULL) ||
1565                                 (store.seen > 1 && multi_replace == 0)) {
1566                         ret = CONFIG_NOTHING_SET;
1567                         goto out_free;
1568                 }
1569
1570                 fstat(in_fd, &st);
1571                 contents_sz = xsize_t(st.st_size);
1572                 contents = xmmap(NULL, contents_sz, PROT_READ,
1573                         MAP_PRIVATE, in_fd, 0);
1574                 close(in_fd);
1575
1576                 if (store.seen == 0)
1577                         store.seen = 1;
1578
1579                 for (i = 0, copy_begin = 0; i < store.seen; i++) {
1580                         if (store.offset[i] == 0) {
1581                                 store.offset[i] = copy_end = contents_sz;
1582                         } else if (store.state != KEY_SEEN) {
1583                                 copy_end = store.offset[i];
1584                         } else
1585                                 copy_end = find_beginning_of_line(
1586                                         contents, contents_sz,
1587                                         store.offset[i]-2, &new_line);
1588
1589                         if (copy_end > 0 && contents[copy_end-1] != '\n')
1590                                 new_line = 1;
1591
1592                         /* write the first part of the config */
1593                         if (copy_end > copy_begin) {
1594                                 if (write_in_full(fd, contents + copy_begin,
1595                                                   copy_end - copy_begin) <
1596                                     copy_end - copy_begin)
1597                                         goto write_err_out;
1598                                 if (new_line &&
1599                                     write_str_in_full(fd, "\n") != 1)
1600                                         goto write_err_out;
1601                         }
1602                         copy_begin = store.offset[i];
1603                 }
1604
1605                 /* write the pair (value == NULL means unset) */
1606                 if (value != NULL) {
1607                         if (store.state == START) {
1608                                 if (!store_write_section(fd, key))
1609                                         goto write_err_out;
1610                         }
1611                         if (!store_write_pair(fd, key, value))
1612                                 goto write_err_out;
1613                 }
1614
1615                 /* write the rest of the config */
1616                 if (copy_begin < contents_sz)
1617                         if (write_in_full(fd, contents + copy_begin,
1618                                           contents_sz - copy_begin) <
1619                             contents_sz - copy_begin)
1620                                 goto write_err_out;
1621
1622                 munmap(contents, contents_sz);
1623         }
1624
1625         if (commit_lock_file(lock) < 0) {
1626                 error("could not commit config file %s", config_filename);
1627                 ret = CONFIG_NO_WRITE;
1628                 goto out_free;
1629         }
1630
1631         /*
1632          * lock is committed, so don't try to roll it back below.
1633          * NOTE: Since lockfile.c keeps a linked list of all created
1634          * lock_file structures, it isn't safe to free(lock).  It's
1635          * better to just leave it hanging around.
1636          */
1637         lock = NULL;
1638         ret = 0;
1639
1640 out_free:
1641         if (lock)
1642                 rollback_lock_file(lock);
1643         free(filename_buf);
1644         return ret;
1645
1646 write_err_out:
1647         ret = write_error(lock->filename);
1648         goto out_free;
1649
1650 }
1651
1652 int git_config_set_multivar(const char *key, const char *value,
1653                         const char *value_regex, int multi_replace)
1654 {
1655         return git_config_set_multivar_in_file(NULL, key, value, value_regex,
1656                                                multi_replace);
1657 }
1658
1659 static int section_name_match (const char *buf, const char *name)
1660 {
1661         int i = 0, j = 0, dot = 0;
1662         if (buf[i] != '[')
1663                 return 0;
1664         for (i = 1; buf[i] && buf[i] != ']'; i++) {
1665                 if (!dot && isspace(buf[i])) {
1666                         dot = 1;
1667                         if (name[j++] != '.')
1668                                 break;
1669                         for (i++; isspace(buf[i]); i++)
1670                                 ; /* do nothing */
1671                         if (buf[i] != '"')
1672                                 break;
1673                         continue;
1674                 }
1675                 if (buf[i] == '\\' && dot)
1676                         i++;
1677                 else if (buf[i] == '"' && dot) {
1678                         for (i++; isspace(buf[i]); i++)
1679                                 ; /* do_nothing */
1680                         break;
1681                 }
1682                 if (buf[i] != name[j++])
1683                         break;
1684         }
1685         if (buf[i] == ']' && name[j] == 0) {
1686                 /*
1687                  * We match, now just find the right length offset by
1688                  * gobbling up any whitespace after it, as well
1689                  */
1690                 i++;
1691                 for (; buf[i] && isspace(buf[i]); i++)
1692                         ; /* do nothing */
1693                 return i;
1694         }
1695         return 0;
1696 }
1697
1698 static int section_name_is_ok(const char *name)
1699 {
1700         /* Empty section names are bogus. */
1701         if (!*name)
1702                 return 0;
1703
1704         /*
1705          * Before a dot, we must be alphanumeric or dash. After the first dot,
1706          * anything goes, so we can stop checking.
1707          */
1708         for (; *name && *name != '.'; name++)
1709                 if (*name != '-' && !isalnum(*name))
1710                         return 0;
1711         return 1;
1712 }
1713
1714 /* if new_name == NULL, the section is removed instead */
1715 int git_config_rename_section_in_file(const char *config_filename,
1716                                       const char *old_name, const char *new_name)
1717 {
1718         int ret = 0, remove = 0;
1719         char *filename_buf = NULL;
1720         struct lock_file *lock;
1721         int out_fd;
1722         char buf[1024];
1723         FILE *config_file;
1724
1725         if (new_name && !section_name_is_ok(new_name)) {
1726                 ret = error("invalid section name: %s", new_name);
1727                 goto out;
1728         }
1729
1730         if (!config_filename)
1731                 config_filename = filename_buf = git_pathdup("config");
1732
1733         lock = xcalloc(sizeof(struct lock_file), 1);
1734         out_fd = hold_lock_file_for_update(lock, config_filename, 0);
1735         if (out_fd < 0) {
1736                 ret = error("could not lock config file %s", config_filename);
1737                 goto out;
1738         }
1739
1740         if (!(config_file = fopen(config_filename, "rb"))) {
1741                 /* no config file means nothing to rename, no error */
1742                 goto unlock_and_out;
1743         }
1744
1745         while (fgets(buf, sizeof(buf), config_file)) {
1746                 int i;
1747                 int length;
1748                 char *output = buf;
1749                 for (i = 0; buf[i] && isspace(buf[i]); i++)
1750                         ; /* do nothing */
1751                 if (buf[i] == '[') {
1752                         /* it's a section */
1753                         int offset = section_name_match(&buf[i], old_name);
1754                         if (offset > 0) {
1755                                 ret++;
1756                                 if (new_name == NULL) {
1757                                         remove = 1;
1758                                         continue;
1759                                 }
1760                                 store.baselen = strlen(new_name);
1761                                 if (!store_write_section(out_fd, new_name)) {
1762                                         ret = write_error(lock->filename);
1763                                         goto out;
1764                                 }
1765                                 /*
1766                                  * We wrote out the new section, with
1767                                  * a newline, now skip the old
1768                                  * section's length
1769                                  */
1770                                 output += offset + i;
1771                                 if (strlen(output) > 0) {
1772                                         /*
1773                                          * More content means there's
1774                                          * a declaration to put on the
1775                                          * next line; indent with a
1776                                          * tab
1777                                          */
1778                                         output -= 1;
1779                                         output[0] = '\t';
1780                                 }
1781                         }
1782                         remove = 0;
1783                 }
1784                 if (remove)
1785                         continue;
1786                 length = strlen(output);
1787                 if (write_in_full(out_fd, output, length) != length) {
1788                         ret = write_error(lock->filename);
1789                         goto out;
1790                 }
1791         }
1792         fclose(config_file);
1793 unlock_and_out:
1794         if (commit_lock_file(lock) < 0)
1795                 ret = error("could not commit config file %s", config_filename);
1796 out:
1797         free(filename_buf);
1798         return ret;
1799 }
1800
1801 int git_config_rename_section(const char *old_name, const char *new_name)
1802 {
1803         return git_config_rename_section_in_file(NULL, old_name, new_name);
1804 }
1805
1806 /*
1807  * Call this to report error for your variable that should not
1808  * get a boolean value (i.e. "[my] var" means "true").
1809  */
1810 #undef config_error_nonbool
1811 int config_error_nonbool(const char *var)
1812 {
1813         return error("Missing value for '%s'", var);
1814 }
1815
1816 int parse_config_key(const char *var,
1817                      const char *section,
1818                      const char **subsection, int *subsection_len,
1819                      const char **key)
1820 {
1821         int section_len = strlen(section);
1822         const char *dot;
1823
1824         /* Does it start with "section." ? */
1825         if (prefixcmp(var, section) || var[section_len] != '.')
1826                 return -1;
1827
1828         /*
1829          * Find the key; we don't know yet if we have a subsection, but we must
1830          * parse backwards from the end, since the subsection may have dots in
1831          * it, too.
1832          */
1833         dot = strrchr(var, '.');
1834         *key = dot + 1;
1835
1836         /* Did we have a subsection at all? */
1837         if (dot == var + section_len) {
1838                 *subsection = NULL;
1839                 *subsection_len = 0;
1840         }
1841         else {
1842                 *subsection = var + section_len + 1;
1843                 *subsection_len = dot - *subsection;
1844         }
1845
1846         return 0;
1847 }