config.c

   1 /*
   2  * GIT - The information manager from hell
   3  *
   4  * Copyright (C) Linus Torvalds, 2005
   5  * Copyright (C) Johannes Schindelin, 2005
   6  *
   7  */
   8 #include "cache.h"
   9 #include "exec_cmd.h"
  10 #include "strbuf.h"
  11 #include "quote.h"
  12
  13 struct config_source {
  14         struct config_source *prev;
  15         union {
  16                 FILE *file;
  17                 struct config_buf {
  18                         const char *buf;
  19                         size_t len;
  20                         size_t pos;
  21                 } buf;
  22         } u;
  23         const char *name;
  24         int die_on_error;
  25         int linenr;
  26         int eof;
  27         struct strbuf value;
  28         struct strbuf var;
  29
  30         int (*fgetc)(struct config_source *c);
  31         int (*ungetc)(int c, struct config_source *conf);
  32         long (*ftell)(struct config_source *c);
  33 };
  34
  35 static struct config_source *cf;
  36
  37 static int zlib_compression_seen;
  38
  39 static int config_file_fgetc(struct config_source *conf)
  40 {
  41         return fgetc(conf->u.file);
  42 }
  43
  44 static int config_file_ungetc(int c, struct config_source *conf)
  45 {
  46         return ungetc(c, conf->u.file);
  47 }
  48
  49 static long config_file_ftell(struct config_source *conf)
  50 {
  51         return ftell(conf->u.file);
  52 }
  53
  54
  55 static int config_buf_fgetc(struct config_source *conf)
  56 {
  57         if (conf->u.buf.pos < conf->u.buf.len)
  58                 return conf->u.buf.buf[conf->u.buf.pos++];
  59
  60         return EOF;
  61 }
  62
  63 static int config_buf_ungetc(int c, struct config_source *conf)
  64 {
  65         if (conf->u.buf.pos > 0)
  66                 return conf->u.buf.buf[--conf->u.buf.pos];
  67
  68         return EOF;
  69 }
  70
  71 static long config_buf_ftell(struct config_source *conf)
  72 {
  73         return conf->u.buf.pos;
  74 }
  75
  76 #define MAX_INCLUDE_DEPTH 10
  77 static const char include_depth_advice[] =
  78 "exceeded maximum include depth (%d) while including\n"
  79 "       %s\n"
  80 "from\n"
  81 "       %s\n"
  82 "Do you have circular includes?";
  83 static int handle_path_include(const char *path, struct config_include_data *inc)
  84 {
  85         int ret = 0;
  86         struct strbuf buf = STRBUF_INIT;
  87         char *expanded = expand_user_path(path);
  88
  89         if (!expanded)
  90                 return error("Could not expand include path '%s'", path);
  91         path = expanded;
  92
  93         /*
  94          * Use an absolute path as-is, but interpret relative paths
  95          * based on the including config file.
  96          */
  97         if (!is_absolute_path(path)) {
  98                 char *slash;
  99
 100                 if (!cf || !cf->name)
 101                         return error("relative config includes must come from files");
 102
 103                 slash = find_last_dir_sep(cf->name);
 104                 if (slash)
 105                         strbuf_add(&buf, cf->name, slash - cf->name + 1);
 106                 strbuf_addstr(&buf, path);
 107                 path = buf.buf;
 108         }
 109
 110         if (!access_or_die(path, R_OK)) {
 111                 if (++inc->depth > MAX_INCLUDE_DEPTH)
 112                         die(include_depth_advice, MAX_INCLUDE_DEPTH, path,
 113                             cf && cf->name ? cf->name : "the command line");
 114                 ret = git_config_from_file(git_config_include, path, inc);
 115                 inc->depth--;
 116         }
 117         strbuf_release(&buf);
 118         free(expanded);
 119         return ret;
 120 }
 121
 122 int git_config_include(const char *var, const char *value, void *data)
 123 {
 124         struct config_include_data *inc = data;
 125         const char *type;
 126         int ret;
 127
 128         /*
 129          * Pass along all values, including "include" directives; this makes it
 130          * possible to query information on the includes themselves.
 131          */
 132         ret = inc->fn(var, value, inc->data);
 133         if (ret < 0)
 134                 return ret;
 135
 136         type = skip_prefix(var, "include.");
 137         if (!type)
 138                 return ret;
 139
 140         if (!strcmp(type, "path"))
 141                 ret = handle_path_include(value, inc);
 142         return ret;
 143 }
 144
 145 static void lowercase(char *p)
 146 {
 147         for (; *p; p++)
 148                 *p = tolower(*p);
 149 }
 150
 151 void git_config_push_parameter(const char *text)
 152 {
 153         struct strbuf env = STRBUF_INIT;
 154         const char *old = getenv(CONFIG_DATA_ENVIRONMENT);
 155         if (old) {
 156                 strbuf_addstr(&env, old);
 157                 strbuf_addch(&env, ' ');
 158         }
 159         sq_quote_buf(&env, text);
 160         setenv(CONFIG_DATA_ENVIRONMENT, env.buf, 1);
 161         strbuf_release(&env);
 162 }
 163
 164 int git_config_parse_parameter(const char *text,
 165                                config_fn_t fn, void *data)
 166 {
 167         struct strbuf **pair;
 168         pair = strbuf_split_str(text, '=', 2);
 169         if (!pair[0])
 170                 return error("bogus config parameter: %s", text);
 171         if (pair[0]->len && pair[0]->buf[pair[0]->len - 1] == '=')
 172                 strbuf_setlen(pair[0], pair[0]->len - 1);
 173         strbuf_trim(pair[0]);
 174         if (!pair[0]->len) {
 175                 strbuf_list_free(pair);
 176                 return error("bogus config parameter: %s", text);
 177         }
 178         lowercase(pair[0]->buf);
 179         if (fn(pair[0]->buf, pair[1] ? pair[1]->buf : NULL, data) < 0) {
 180                 strbuf_list_free(pair);
 181                 return -1;
 182         }
 183         strbuf_list_free(pair);
 184         return 0;
 185 }
 186
 187 int git_config_from_parameters(config_fn_t fn, void *data)
 188 {
 189         const char *env = getenv(CONFIG_DATA_ENVIRONMENT);
 190         char *envw;
 191         const char **argv = NULL;
 192         int nr = 0, alloc = 0;
 193         int i;
 194
 195         if (!env)
 196                 return 0;
 197         /* sq_dequote will write over it */
 198         envw = xstrdup(env);
 199
 200         if (sq_dequote_to_argv(envw, &argv, &nr, &alloc) < 0) {
 201                 free(envw);
 202                 return error("bogus format in " CONFIG_DATA_ENVIRONMENT);
 203         }
 204
 205         for (i = 0; i < nr; i++) {
 206                 if (git_config_parse_parameter(argv[i], fn, data) < 0) {
 207                         free(argv);
 208                         free(envw);
 209                         return -1;
 210                 }
 211         }
 212
 213         free(argv);
 214         free(envw);
 215         return nr > 0;
 216 }
 217
 218 static int get_next_char(void)
 219 {
 220         int c = cf->fgetc(cf);
 221
 222         if (c == '\r') {
 223                 /* DOS like systems */
 224                 c = cf->fgetc(cf);
 225                 if (c != '\n') {
 226                         cf->ungetc(c, cf);
 227                         c = '\r';
 228                 }
 229         }
 230         if (c == '\n')
 231                 cf->linenr++;
 232         if (c == EOF) {
 233                 cf->eof = 1;
 234                 c = '\n';
 235         }
 236         return c;
 237 }
 238
 239 static char *parse_value(void)
 240 {
 241         int quote = 0, comment = 0, space = 0;
 242
 243         strbuf_reset(&cf->value);
 244         for (;;) {
 245                 int c = get_next_char();
 246                 if (c == '\n') {
 247                         if (quote) {
 248                                 cf->linenr--;
 249                                 return NULL;
 250                         }
 251                         return cf->value.buf;
 252                 }
 253                 if (comment)
 254                         continue;
 255                 if (isspace(c) && !quote) {
 256                         if (cf->value.len)
 257                                 space++;
 258                         continue;
 259                 }
 260                 if (!quote) {
 261                         if (c == ';' || c == '#') {
 262                                 comment = 1;
 263                                 continue;
 264                         }
 265                 }
 266                 for (; space; space--)
 267                         strbuf_addch(&cf->value, ' ');
 268                 if (c == '\\') {
 269                         c = get_next_char();
 270                         switch (c) {
 271                         case '\n':
 272                                 continue;
 273                         case 't':
 274                                 c = '\t';
 275                                 break;
 276                         case 'b':
 277                                 c = '\b';
 278                                 break;
 279                         case 'n':
 280                                 c = '\n';
 281                                 break;
 282                         /* Some characters escape as themselves */
 283                         case '\\': case '"':
 284                                 break;
 285                         /* Reject unknown escape sequences */
 286                         default:
 287                                 return NULL;
 288                         }
 289                         strbuf_addch(&cf->value, c);
 290                         continue;
 291                 }
 292                 if (c == '"') {
 293                         quote = 1-quote;
 294                         continue;
 295                 }
 296                 strbuf_addch(&cf->value, c);
 297         }
 298 }
 299
 300 static inline int iskeychar(int c)
 301 {
 302         return isalnum(c) || c == '-';
 303 }
 304
 305 static int get_value(config_fn_t fn, void *data, struct strbuf *name)
 306 {
 307         int c;
 308         char *value;
 309
 310         /* Get the full name */
 311         for (;;) {
 312                 c = get_next_char();
 313                 if (cf->eof)
 314                         break;
 315                 if (!iskeychar(c))
 316                         break;
 317                 strbuf_addch(name, tolower(c));
 318         }
 319
 320         while (c == ' ' || c == '\t')
 321                 c = get_next_char();
 322
 323         value = NULL;
 324         if (c != '\n') {
 325                 if (c != '=')
 326                         return -1;
 327                 value = parse_value();
 328                 if (!value)
 329                         return -1;
 330         }
 331         return fn(name->buf, value, data);
 332 }
 333
 334 static int get_extended_base_var(struct strbuf *name, int c)
 335 {
 336         do {
 337                 if (c == '\n')
 338                         goto error_incomplete_line;
 339                 c = get_next_char();
 340         } while (isspace(c));
 341
 342         /* We require the format to be '[base "extension"]' */
 343         if (c != '"')
 344                 return -1;
 345         strbuf_addch(name, '.');
 346
 347         for (;;) {
 348                 int c = get_next_char();
 349                 if (c == '\n')
 350                         goto error_incomplete_line;
 351                 if (c == '"')
 352                         break;
 353                 if (c == '\\') {
 354                         c = get_next_char();
 355                         if (c == '\n')
 356                                 goto error_incomplete_line;
 357                 }
 358                 strbuf_addch(name, c);
 359         }
 360
 361         /* Final ']' */
 362         if (get_next_char() != ']')
 363                 return -1;
 364         return 0;
 365 error_incomplete_line:
 366         cf->linenr--;
 367         return -1;
 368 }
 369
 370 static int get_base_var(struct strbuf *name)
 371 {
 372         for (;;) {
 373                 int c = get_next_char();
 374                 if (cf->eof)
 375                         return -1;
 376                 if (c == ']')
 377                         return 0;
 378                 if (isspace(c))
 379                         return get_extended_base_var(name, c);
 380                 if (!iskeychar(c) && c != '.')
 381                         return -1;
 382                 strbuf_addch(name, tolower(c));
 383         }
 384 }
 385
 386 static int git_parse_source(config_fn_t fn, void *data)
 387 {
 388         int comment = 0;
 389         int baselen = 0;
 390         struct strbuf *var = &cf->var;
 391
 392         /* U+FEFF Byte Order Mark in UTF8 */
 393         static const unsigned char *utf8_bom = (unsigned char *) "\xef\xbb\xbf";
 394         const unsigned char *bomptr = utf8_bom;
 395
 396         for (;;) {
 397                 int c = get_next_char();
 398                 if (bomptr && *bomptr) {
 399                         /* We are at the file beginning; skip UTF8-encoded BOM
 400                          * if present. Sane editors won't put this in on their
 401                          * own, but e.g. Windows Notepad will do it happily. */
 402                         if ((unsigned char) c == *bomptr) {
 403                                 bomptr++;
 404                                 continue;
 405                         } else {
 406                                 /* Do not tolerate partial BOM. */
 407                                 if (bomptr != utf8_bom)
 408                                         break;
 409                                 /* No BOM at file beginning. Cool. */
 410                                 bomptr = NULL;
 411                         }
 412                 }
 413                 if (c == '\n') {
 414                         if (cf->eof)
 415                                 return 0;
 416                         comment = 0;
 417                         continue;
 418                 }
 419                 if (comment || isspace(c))
 420                         continue;
 421                 if (c == '#' || c == ';') {
 422                         comment = 1;
 423                         continue;
 424                 }
 425                 if (c == '[') {
 426                         /* Reset prior to determining a new stem */
 427                         strbuf_reset(var);
 428                         if (get_base_var(var) < 0 || var->len < 1)
 429                                 break;
 430                         strbuf_addch(var, '.');
 431                         baselen = var->len;
 432                         continue;
 433                 }
 434                 if (!isalpha(c))
 435                         break;
 436                 /*
 437                  * Truncate the var name back to the section header
 438                  * stem prior to grabbing the suffix part of the name
 439                  * and the value.
 440                  */
 441                 strbuf_setlen(var, baselen);
 442                 strbuf_addch(var, tolower(c));
 443                 if (get_value(fn, data, var) < 0)
 444                         break;
 445         }
 446         if (cf->die_on_error)
 447                 die("bad config file line %d in %s", cf->linenr, cf->name);
 448         else
 449                 return error("bad config file line %d in %s", cf->linenr, cf->name);
 450 }
 451
 452 static int parse_unit_factor(const char *end, uintmax_t *val)
 453 {
 454         if (!*end)
 455                 return 1;
 456         else if (!strcasecmp(end, "k")) {
 457                 *val *= 1024;
 458                 return 1;
 459         }
 460         else if (!strcasecmp(end, "m")) {
 461                 *val *= 1024 * 1024;
 462                 return 1;
 463         }
 464         else if (!strcasecmp(end, "g")) {
 465                 *val *= 1024 * 1024 * 1024;
 466                 return 1;
 467         }
 468         return 0;
 469 }
 470
 471 static int git_parse_long(const char *value, long *ret)
 472 {
 473         if (value && *value) {
 474                 char *end;
 475                 intmax_t val;
 476                 uintmax_t uval;
 477                 uintmax_t factor = 1;
 478
 479                 errno = 0;
 480                 val = strtoimax(value, &end, 0);
 481                 if (errno == ERANGE)
 482                         return 0;
 483                 if (!parse_unit_factor(end, &factor))
 484                         return 0;
 485                 uval = abs(val);
 486                 uval *= factor;
 487                 if ((uval > maximum_signed_value_of_type(long)) ||
 488                     (abs(val) > uval))
 489                         return 0;
 490                 val *= factor;
 491                 *ret = val;
 492                 return 1;
 493         }
 494         return 0;
 495 }
 496
 497 int git_parse_ulong(const char *value, unsigned long *ret)
 498 {
 499         if (value && *value) {
 500                 char *end;
 501                 uintmax_t val;
 502                 uintmax_t oldval;
 503
 504                 errno = 0;
 505                 val = strtoumax(value, &end, 0);
 506                 if (errno == ERANGE)
 507                         return 0;
 508                 oldval = val;
 509                 if (!parse_unit_factor(end, &val))
 510                         return 0;
 511                 if ((val > maximum_unsigned_value_of_type(long)) ||
 512                     (oldval > val))
 513                         return 0;
 514                 *ret = val;
 515                 return 1;
 516         }
 517         return 0;
 518 }
 519
 520 static void die_bad_config(const char *name)
 521 {
 522         if (cf && cf->name)
 523                 die("bad config value for '%s' in %s", name, cf->name);
 524         die("bad config value for '%s'", name);
 525 }
 526
 527 int git_config_int(const char *name, const char *value)
 528 {
 529         long ret = 0;
 530         if (!git_parse_long(value, &ret))
 531                 die_bad_config(name);
 532         return ret;
 533 }
 534
 535 unsigned long git_config_ulong(const char *name, const char *value)
 536 {
 537         unsigned long ret;
 538         if (!git_parse_ulong(value, &ret))
 539                 die_bad_config(name);
 540         return ret;
 541 }
 542
 543 static int git_config_maybe_bool_text(const char *name, const char *value)
 544 {
 545         if (!value)
 546                 return 1;
 547         if (!*value)
 548                 return 0;
 549         if (!strcasecmp(value, "true")
 550             || !strcasecmp(value, "yes")
 551             || !strcasecmp(value, "on"))
 552                 return 1;
 553         if (!strcasecmp(value, "false")
 554             || !strcasecmp(value, "no")
 555             || !strcasecmp(value, "off"))
 556                 return 0;
 557         return -1;
 558 }
 559
 560 int git_config_maybe_bool(const char *name, const char *value)
 561 {
 562         long v = git_config_maybe_bool_text(name, value);
 563         if (0 <= v)
 564                 return v;
 565         if (git_parse_long(value, &v))
 566                 return !!v;
 567         return -1;
 568 }
 569
 570 int git_config_bool_or_int(const char *name, const char *value, int *is_bool)
 571 {
 572         int v = git_config_maybe_bool_text(name, value);
 573         if (0 <= v) {
 574                 *is_bool = 1;
 575                 return v;
 576         }
 577         *is_bool = 0;
 578         return git_config_int(name, value);
 579 }
 580
 581 int git_config_bool(const char *name, const char *value)
 582 {
 583         int discard;
 584         return !!git_config_bool_or_int(name, value, &discard);
 585 }
 586
 587 int git_config_string(const char **dest, const char *var, const char *value)
 588 {
 589         if (!value)
 590                 return config_error_nonbool(var);
 591         *dest = xstrdup(value);
 592         return 0;
 593 }
 594
 595 int git_config_pathname(const char **dest, const char *var, const char *value)
 596 {
 597         if (!value)
 598                 return config_error_nonbool(var);
 599         *dest = expand_user_path(value);
 600         if (!*dest)
 601                 die("Failed to expand user dir in: '%s'", value);
 602         return 0;
 603 }
 604
 605 static int git_default_core_config(const char *var, const char *value)
 606 {
 607         /* This needs a better name */
 608         if (!strcmp(var, "core.filemode")) {
 609                 trust_executable_bit = git_config_bool(var, value);
 610                 return 0;
 611         }
 612         if (!strcmp(var, "core.trustctime")) {
 613                 trust_ctime = git_config_bool(var, value);
 614                 return 0;
 615         }
 616         if (!strcmp(var, "core.statinfo")) {
 617                 if (!strcasecmp(value, "default"))
 618                         check_stat = 1;
 619                 else if (!strcasecmp(value, "minimal"))
 620                         check_stat = 0;
 621         }
 622
 623         if (!strcmp(var, "core.quotepath")) {
 624                 quote_path_fully = git_config_bool(var, value);
 625                 return 0;
 626         }
 627
 628         if (!strcmp(var, "core.symlinks")) {
 629                 has_symlinks = git_config_bool(var, value);
 630                 return 0;
 631         }
 632
 633         if (!strcmp(var, "core.ignorecase")) {
 634                 ignore_case = git_config_bool(var, value);
 635                 return 0;
 636         }
 637
 638         if (!strcmp(var, "core.attributesfile"))
 639                 return git_config_pathname(&git_attributes_file, var, value);
 640
 641         if (!strcmp(var, "core.bare")) {
 642                 is_bare_repository_cfg = git_config_bool(var, value);
 643                 return 0;
 644         }
 645
 646         if (!strcmp(var, "core.ignorestat")) {
 647                 assume_unchanged = git_config_bool(var, value);
 648                 return 0;
 649         }
 650
 651         if (!strcmp(var, "core.prefersymlinkrefs")) {
 652                 prefer_symlink_refs = git_config_bool(var, value);
 653                 return 0;
 654         }
 655
 656         if (!strcmp(var, "core.logallrefupdates")) {
 657                 log_all_ref_updates = git_config_bool(var, value);
 658                 return 0;
 659         }
 660
 661         if (!strcmp(var, "core.warnambiguousrefs")) {
 662                 warn_ambiguous_refs = git_config_bool(var, value);
 663                 return 0;
 664         }
 665
 666         if (!strcmp(var, "core.abbrev")) {
 667                 int abbrev = git_config_int(var, value);
 668                 if (abbrev < minimum_abbrev || abbrev > 40)
 669                         return -1;
 670                 default_abbrev = abbrev;
 671                 return 0;
 672         }
 673
 674         if (!strcmp(var, "core.loosecompression")) {
 675                 int level = git_config_int(var, value);
 676                 if (level == -1)
 677                         level = Z_DEFAULT_COMPRESSION;
 678                 else if (level < 0 || level > Z_BEST_COMPRESSION)
 679                         die("bad zlib compression level %d", level);
 680                 zlib_compression_level = level;
 681                 zlib_compression_seen = 1;
 682                 return 0;
 683         }
 684
 685         if (!strcmp(var, "core.compression")) {
 686                 int level = git_config_int(var, value);
 687                 if (level == -1)
 688                         level = Z_DEFAULT_COMPRESSION;
 689                 else if (level < 0 || level > Z_BEST_COMPRESSION)
 690                         die("bad zlib compression level %d", level);
 691                 core_compression_level = level;
 692                 core_compression_seen = 1;
 693                 if (!zlib_compression_seen)
 694                         zlib_compression_level = level;
 695                 return 0;
 696         }
 697
 698         if (!strcmp(var, "core.packedgitwindowsize")) {
 699                 int pgsz_x2 = getpagesize() * 2;
 700                 packed_git_window_size = git_config_ulong(var, value);
 701
 702                 /* This value must be multiple of (pagesize * 2) */
 703                 packed_git_window_size /= pgsz_x2;
 704                 if (packed_git_window_size < 1)
 705                         packed_git_window_size = 1;
 706                 packed_git_window_size *= pgsz_x2;
 707                 return 0;
 708         }
 709
 710         if (!strcmp(var, "core.bigfilethreshold")) {
 711                 big_file_threshold = git_config_ulong(var, value);
 712                 return 0;
 713         }
 714
 715         if (!strcmp(var, "core.packedgitlimit")) {
 716                 packed_git_limit = git_config_ulong(var, value);
 717                 return 0;
 718         }
 719
 720         if (!strcmp(var, "core.deltabasecachelimit")) {
 721                 delta_base_cache_limit = git_config_ulong(var, value);
 722                 return 0;
 723         }
 724
 725         if (!strcmp(var, "core.logpackaccess"))
 726                 return git_config_string(&log_pack_access, var, value);
 727
 728         if (!strcmp(var, "core.autocrlf")) {
 729                 if (value && !strcasecmp(value, "input")) {
 730                         if (core_eol == EOL_CRLF)
 731                                 return error("core.autocrlf=input conflicts with core.eol=crlf");
 732                         auto_crlf = AUTO_CRLF_INPUT;
 733                         return 0;
 734                 }
 735                 auto_crlf = git_config_bool(var, value);
 736                 return 0;
 737         }
 738
 739         if (!strcmp(var, "core.safecrlf")) {
 740                 if (value && !strcasecmp(value, "warn")) {
 741                         safe_crlf = SAFE_CRLF_WARN;
 742                         return 0;
 743                 }
 744                 safe_crlf = git_config_bool(var, value);
 745                 return 0;
 746         }
 747
 748         if (!strcmp(var, "core.eol")) {
 749                 if (value && !strcasecmp(value, "lf"))
 750                         core_eol = EOL_LF;
 751                 else if (value && !strcasecmp(value, "crlf"))
 752                         core_eol = EOL_CRLF;
 753                 else if (value && !strcasecmp(value, "native"))
 754                         core_eol = EOL_NATIVE;
 755                 else
 756                         core_eol = EOL_UNSET;
 757                 if (core_eol == EOL_CRLF && auto_crlf == AUTO_CRLF_INPUT)
 758                         return error("core.autocrlf=input conflicts with core.eol=crlf");
 759                 return 0;
 760         }
 761
 762         if (!strcmp(var, "core.notesref")) {
 763                 notes_ref_name = xstrdup(value);
 764                 return 0;
 765         }
 766
 767         if (!strcmp(var, "core.pager"))
 768                 return git_config_string(&pager_program, var, value);
 769
 770         if (!strcmp(var, "core.editor"))
 771                 return git_config_string(&editor_program, var, value);
 772
 773         if (!strcmp(var, "core.commentchar")) {
 774                 const char *comment;
 775                 int ret = git_config_string(&comment, var, value);
 776                 if (!ret)
 777                         comment_line_char = comment[0];
 778                 return ret;
 779         }
 780
 781         if (!strcmp(var, "core.askpass"))
 782                 return git_config_string(&askpass_program, var, value);
 783
 784         if (!strcmp(var, "core.excludesfile"))
 785                 return git_config_pathname(&excludes_file, var, value);
 786
 787         if (!strcmp(var, "core.whitespace")) {
 788                 if (!value)
 789                         return config_error_nonbool(var);
 790                 whitespace_rule_cfg = parse_whitespace_rule(value);
 791                 return 0;
 792         }
 793
 794         if (!strcmp(var, "core.fsyncobjectfiles")) {
 795                 fsync_object_files = git_config_bool(var, value);
 796                 return 0;
 797         }
 798
 799         if (!strcmp(var, "core.preloadindex")) {
 800                 core_preload_index = git_config_bool(var, value);
 801                 return 0;
 802         }
 803
 804         if (!strcmp(var, "core.createobject")) {
 805                 if (!strcmp(value, "rename"))
 806                         object_creation_mode = OBJECT_CREATION_USES_RENAMES;
 807                 else if (!strcmp(value, "link"))
 808                         object_creation_mode = OBJECT_CREATION_USES_HARDLINKS;
 809                 else
 810                         die("Invalid mode for object creation: %s", value);
 811                 return 0;
 812         }
 813
 814         if (!strcmp(var, "core.sparsecheckout")) {
 815                 core_apply_sparse_checkout = git_config_bool(var, value);
 816                 return 0;
 817         }
 818
 819         if (!strcmp(var, "core.precomposeunicode")) {
 820                 precomposed_unicode = git_config_bool(var, value);
 821                 return 0;
 822         }
 823
 824         /* Add other config variables here and to Documentation/config.txt. */
 825         return 0;
 826 }
 827
 828 static int git_default_i18n_config(const char *var, const char *value)
 829 {
 830         if (!strcmp(var, "i18n.commitencoding"))
 831                 return git_config_string(&git_commit_encoding, var, value);
 832
 833         if (!strcmp(var, "i18n.logoutputencoding"))
 834                 return git_config_string(&git_log_output_encoding, var, value);
 835
 836         /* Add other config variables here and to Documentation/config.txt. */
 837         return 0;
 838 }
 839
 840 static int git_default_branch_config(const char *var, const char *value)
 841 {
 842         if (!strcmp(var, "branch.autosetupmerge")) {
 843                 if (value && !strcasecmp(value, "always")) {
 844                         git_branch_track = BRANCH_TRACK_ALWAYS;
 845                         return 0;
 846                 }
 847                 git_branch_track = git_config_bool(var, value);
 848                 return 0;
 849         }
 850         if (!strcmp(var, "branch.autosetuprebase")) {
 851                 if (!value)
 852                         return config_error_nonbool(var);
 853                 else if (!strcmp(value, "never"))
 854                         autorebase = AUTOREBASE_NEVER;
 855                 else if (!strcmp(value, "local"))
 856                         autorebase = AUTOREBASE_LOCAL;
 857                 else if (!strcmp(value, "remote"))
 858                         autorebase = AUTOREBASE_REMOTE;
 859                 else if (!strcmp(value, "always"))
 860                         autorebase = AUTOREBASE_ALWAYS;
 861                 else
 862                         return error("Malformed value for %s", var);
 863                 return 0;
 864         }
 865
 866         /* Add other config variables here and to Documentation/config.txt. */
 867         return 0;
 868 }
 869
 870 static int git_default_push_config(const char *var, const char *value)
 871 {
 872         if (!strcmp(var, "push.default")) {
 873                 if (!value)
 874                         return config_error_nonbool(var);
 875                 else if (!strcmp(value, "nothing"))
 876                         push_default = PUSH_DEFAULT_NOTHING;
 877                 else if (!strcmp(value, "matching"))
 878                         push_default = PUSH_DEFAULT_MATCHING;
 879                 else if (!strcmp(value, "simple"))
 880                         push_default = PUSH_DEFAULT_SIMPLE;
 881                 else if (!strcmp(value, "upstream"))
 882                         push_default = PUSH_DEFAULT_UPSTREAM;
 883                 else if (!strcmp(value, "tracking")) /* deprecated */
 884                         push_default = PUSH_DEFAULT_UPSTREAM;
 885                 else if (!strcmp(value, "current"))
 886                         push_default = PUSH_DEFAULT_CURRENT;
 887                 else {
 888                         error("Malformed value for %s: %s", var, value);
 889                         return error("Must be one of nothing, matching, simple, "
 890                                      "upstream or current.");
 891                 }
 892                 return 0;
 893         }
 894
 895         /* Add other config variables here and to Documentation/config.txt. */
 896         return 0;
 897 }
 898
 899 static int git_default_mailmap_config(const char *var, const char *value)
 900 {
 901         if (!strcmp(var, "mailmap.file"))
 902                 return git_config_string(&git_mailmap_file, var, value);
 903         if (!strcmp(var, "mailmap.blob"))
 904                 return git_config_string(&git_mailmap_blob, var, value);
 905
 906         /* Add other config variables here and to Documentation/config.txt. */
 907         return 0;
 908 }
 909
 910 int git_default_config(const char *var, const char *value, void *dummy)
 911 {
 912         if (!prefixcmp(var, "core."))
 913                 return git_default_core_config(var, value);
 914
 915         if (!prefixcmp(var, "user."))
 916                 return git_ident_config(var, value, dummy);
 917
 918         if (!prefixcmp(var, "i18n."))
 919                 return git_default_i18n_config(var, value);
 920
 921         if (!prefixcmp(var, "branch."))
 922                 return git_default_branch_config(var, value);
 923
 924         if (!prefixcmp(var, "push."))
 925                 return git_default_push_config(var, value);
 926
 927         if (!prefixcmp(var, "mailmap."))
 928                 return git_default_mailmap_config(var, value);
 929
 930         if (!prefixcmp(var, "advice."))
 931                 return git_default_advice_config(var, value);
 932
 933         if (!strcmp(var, "pager.color") || !strcmp(var, "color.pager")) {
 934                 pager_use_color = git_config_bool(var,value);
 935                 return 0;
 936         }
 937
 938         if (!strcmp(var, "pack.packsizelimit")) {
 939                 pack_size_limit_cfg = git_config_ulong(var, value);
 940                 return 0;
 941         }
 942         /* Add other config variables here and to Documentation/config.txt. */
 943         return 0;
 944 }
 945
 946 /*
 947  * All source specific fields in the union, die_on_error, name and the callbacks
 948  * fgetc, ungetc, ftell of top need to be initialized before calling
 949  * this function.
 950  */
 951 static int do_config_from(struct config_source *top, config_fn_t fn, void *data)
 952 {
 953         int ret;
 954
 955         /* push config-file parsing state stack */
 956         top->prev = cf;
 957         top->linenr = 1;
 958         top->eof = 0;
 959         strbuf_init(&top->value, 1024);
 960         strbuf_init(&top->var, 1024);
 961         cf = top;
 962
 963         ret = git_parse_source(fn, data);
 964
 965         /* pop config-file parsing state stack */
 966         strbuf_release(&top->value);
 967         strbuf_release(&top->var);
 968         cf = top->prev;
 969
 970         return ret;
 971 }
 972
 973 int git_config_from_file(config_fn_t fn, const char *filename, void *data)
 974 {
 975         int ret;
 976         FILE *f = fopen(filename, "r");
 977
 978         ret = -1;
 979         if (f) {
 980                 struct config_source top;
 981
 982                 top.u.file = f;
 983                 top.name = filename;
 984                 top.die_on_error = 1;
 985                 top.fgetc = config_file_fgetc;
 986                 top.ungetc = config_file_ungetc;
 987                 top.ftell = config_file_ftell;
 988
 989                 ret = do_config_from(&top, fn, data);
 990
 991                 fclose(f);
 992         }
 993         return ret;
 994 }
 995
 996 int git_config_from_buf(config_fn_t fn, const char *name, const char *buf,
 997                         size_t len, void *data)
 998 {
 999         struct config_source top;
1000
1001         top.u.buf.buf = buf;
1002         top.u.buf.len = len;
1003         top.u.buf.pos = 0;
1004         top.name = name;
1005         top.die_on_error = 0;
1006         top.fgetc = config_buf_fgetc;
1007         top.ungetc = config_buf_ungetc;
1008         top.ftell = config_buf_ftell;
1009
1010         return do_config_from(&top, fn, data);
1011 }
1012
1013 static int git_config_from_blob_sha1(config_fn_t fn,
1014                                      const char *name,
1015                                      const unsigned char *sha1,
1016                                      void *data)
1017 {
1018         enum object_type type;
1019         char *buf;
1020         unsigned long size;
1021         int ret;
1022
1023         buf = read_sha1_file(sha1, &type, &size);
1024         if (!buf)
1025                 return error("unable to load config blob object '%s'", name);
1026         if (type != OBJ_BLOB) {
1027                 free(buf);
1028                 return error("reference '%s' does not point to a blob", name);
1029         }
1030
1031         ret = git_config_from_buf(fn, name, buf, size, data);
1032         free(buf);
1033
1034         return ret;
1035 }
1036
1037 static int git_config_from_blob_ref(config_fn_t fn,
1038                                     const char *name,
1039                                     void *data)
1040 {
1041         unsigned char sha1[20];
1042
1043         if (get_sha1(name, sha1) < 0)
1044                 return error("unable to resolve config blob '%s'", name);
1045         return git_config_from_blob_sha1(fn, name, sha1, data);
1046 }
1047
1048 const char *git_etc_gitconfig(void)
1049 {
1050         static const char *system_wide;
1051         if (!system_wide)
1052                 system_wide = system_path(ETC_GITCONFIG);
1053         return system_wide;
1054 }
1055
1056 int git_env_bool(const char *k, int def)
1057 {
1058         const char *v = getenv(k);
1059         return v ? git_config_bool(k, v) : def;
1060 }
1061
1062 int git_config_system(void)
1063 {
1064         return !git_env_bool("GIT_CONFIG_NOSYSTEM", 0);
1065 }
1066
1067 int git_config_early(config_fn_t fn, void *data, const char *repo_config)
1068 {
1069         int ret = 0, found = 0;
1070         char *xdg_config = NULL;
1071         char *user_config = NULL;
1072
1073         home_config_paths(&user_config, &xdg_config, "config");
1074
1075         if (git_config_system() && !access_or_die(git_etc_gitconfig(), R_OK)) {
1076                 ret += git_config_from_file(fn, git_etc_gitconfig(),
1077                                             data);
1078                 found += 1;
1079         }
1080
1081         if (xdg_config && !access_or_die(xdg_config, R_OK)) {
1082                 ret += git_config_from_file(fn, xdg_config, data);
1083                 found += 1;
1084         }
1085
1086         if (user_config && !access_or_die(user_config, R_OK)) {
1087                 ret += git_config_from_file(fn, user_config, data);
1088                 found += 1;
1089         }
1090
1091         if (repo_config && !access_or_die(repo_config, R_OK)) {
1092                 ret += git_config_from_file(fn, repo_config, data);
1093                 found += 1;
1094         }
1095
1096         switch (git_config_from_parameters(fn, data)) {
1097         case -1: /* error */
1098                 die("unable to parse command-line config");
1099                 break;
1100         case 0: /* found nothing */
1101                 break;
1102         default: /* found at least one item */
1103                 found++;
1104                 break;
1105         }
1106
1107         free(xdg_config);
1108         free(user_config);
1109         return ret == 0 ? found : ret;
1110 }
1111
1112 int git_config_with_options(config_fn_t fn, void *data,
1113                             const char *filename,
1114                             const char *blob_ref,
1115                             int respect_includes)
1116 {
1117         char *repo_config = NULL;
1118         int ret;
1119         struct config_include_data inc = CONFIG_INCLUDE_INIT;
1120
1121         if (respect_includes) {
1122                 inc.fn = fn;
1123                 inc.data = data;
1124                 fn = git_config_include;
1125                 data = &inc;
1126         }
1127
1128         /*
1129          * If we have a specific filename, use it. Otherwise, follow the
1130          * regular lookup sequence.
1131          */
1132         if (filename)
1133                 return git_config_from_file(fn, filename, data);
1134         else if (blob_ref)
1135                 return git_config_from_blob_ref(fn, blob_ref, data);
1136
1137         repo_config = git_pathdup("config");
1138         ret = git_config_early(fn, data, repo_config);
1139         if (repo_config)
1140                 free(repo_config);
1141         return ret;
1142 }
1143
1144 int git_config(config_fn_t fn, void *data)
1145 {
1146         return git_config_with_options(fn, data, NULL, NULL, 1);
1147 }
1148
1149 /*
1150  * Find all the stuff for git_config_set() below.
1151  */
1152
1153 #define MAX_MATCHES 512
1154
1155 static struct {
1156         int baselen;
1157         char *key;
1158         int do_not_match;
1159         regex_t *value_regex;
1160         int multi_replace;
1161         size_t offset[MAX_MATCHES];
1162         enum { START, SECTION_SEEN, SECTION_END_SEEN, KEY_SEEN } state;
1163         int seen;
1164 } store;
1165
1166 static int matches(const char *key, const char *value)
1167 {
1168         return !strcmp(key, store.key) &&
1169                 (store.value_regex == NULL ||
1170                  (store.do_not_match ^
1171                   !regexec(store.value_regex, value, 0, NULL, 0)));
1172 }
1173
1174 static int store_aux(const char *key, const char *value, void *cb)
1175 {
1176         const char *ep;
1177         size_t section_len;
1178
1179         switch (store.state) {
1180         case KEY_SEEN:
1181                 if (matches(key, value)) {
1182                         if (store.seen == 1 && store.multi_replace == 0) {
1183                                 warning("%s has multiple values", key);
1184                         } else if (store.seen >= MAX_MATCHES) {
1185                                 error("too many matches for %s", key);
1186                                 return 1;
1187                         }
1188
1189                         store.offset[store.seen] = cf->ftell(cf);
1190                         store.seen++;
1191                 }
1192                 break;
1193         case SECTION_SEEN:
1194                 /*
1195                  * What we are looking for is in store.key (both
1196                  * section and var), and its section part is baselen
1197                  * long.  We found key (again, both section and var).
1198                  * We would want to know if this key is in the same
1199                  * section as what we are looking for.  We already
1200                  * know we are in the same section as what should
1201                  * hold store.key.
1202                  */
1203                 ep = strrchr(key, '.');
1204                 section_len = ep - key;
1205
1206                 if ((section_len != store.baselen) ||
1207                     memcmp(key, store.key, section_len+1)) {
1208                         store.state = SECTION_END_SEEN;
1209                         break;
1210                 }
1211
1212                 /*
1213                  * Do not increment matches: this is no match, but we
1214                  * just made sure we are in the desired section.
1215                  */
1216                 store.offset[store.seen] = cf->ftell(cf);
1217                 /* fallthru */
1218         case SECTION_END_SEEN:
1219         case START:
1220                 if (matches(key, value)) {
1221                         store.offset[store.seen] = cf->ftell(cf);
1222                         store.state = KEY_SEEN;
1223                         store.seen++;
1224                 } else {
1225                         if (strrchr(key, '.') - key == store.baselen &&
1226                               !strncmp(key, store.key, store.baselen)) {
1227                                         store.state = SECTION_SEEN;
1228                                         store.offset[store.seen] = cf->ftell(cf);
1229                         }
1230                 }
1231         }
1232         return 0;
1233 }
1234
1235 static int write_error(const char *filename)
1236 {
1237         error("failed to write new configuration file %s", filename);
1238
1239         /* Same error code as "failed to rename". */
1240         return 4;
1241 }
1242
1243 static int store_write_section(int fd, const char *key)
1244 {
1245         const char *dot;
1246         int i, success;
1247         struct strbuf sb = STRBUF_INIT;
1248
1249         dot = memchr(key, '.', store.baselen);
1250         if (dot) {
1251                 strbuf_addf(&sb, "[%.*s \"", (int)(dot - key), key);
1252                 for (i = dot - key + 1; i < store.baselen; i++) {
1253                         if (key[i] == '"' || key[i] == '\\')
1254                                 strbuf_addch(&sb, '\\');
1255                         strbuf_addch(&sb, key[i]);
1256                 }
1257                 strbuf_addstr(&sb, "\"]\n");
1258         } else {
1259                 strbuf_addf(&sb, "[%.*s]\n", store.baselen, key);
1260         }
1261
1262         success = write_in_full(fd, sb.buf, sb.len) == sb.len;
1263         strbuf_release(&sb);
1264
1265         return success;
1266 }
1267
1268 static int store_write_pair(int fd, const char *key, const char *value)
1269 {
1270         int i, success;
1271         int length = strlen(key + store.baselen + 1);
1272         const char *quote = "";
1273         struct strbuf sb = STRBUF_INIT;
1274
1275         /*
1276          * Check to see if the value needs to be surrounded with a dq pair.
1277          * Note that problematic characters are always backslash-quoted; this
1278          * check is about not losing leading or trailing SP and strings that
1279          * follow beginning-of-comment characters (i.e. ';' and '#') by the
1280          * configuration parser.
1281          */
1282         if (value[0] == ' ')
1283                 quote = "\"";
1284         for (i = 0; value[i]; i++)
1285                 if (value[i] == ';' || value[i] == '#')
1286                         quote = "\"";
1287         if (i && value[i - 1] == ' ')
1288                 quote = "\"";
1289
1290         strbuf_addf(&sb, "\t%.*s = %s",
1291                     length, key + store.baselen + 1, quote);
1292
1293         for (i = 0; value[i]; i++)
1294                 switch (value[i]) {
1295                 case '\n':
1296                         strbuf_addstr(&sb, "\\n");
1297                         break;
1298                 case '\t':
1299                         strbuf_addstr(&sb, "\\t");
1300                         break;
1301                 case '"':
1302                 case '\\':
1303                         strbuf_addch(&sb, '\\');
1304                 default:
1305                         strbuf_addch(&sb, value[i]);
1306                         break;
1307                 }
1308         strbuf_addf(&sb, "%s\n", quote);
1309
1310         success = write_in_full(fd, sb.buf, sb.len) == sb.len;
1311         strbuf_release(&sb);
1312
1313         return success;
1314 }
1315
1316 static ssize_t find_beginning_of_line(const char *contents, size_t size,
1317         size_t offset_, int *found_bracket)
1318 {
1319         size_t equal_offset = size, bracket_offset = size;
1320         ssize_t offset;
1321
1322 contline:
1323         for (offset = offset_-2; offset > 0
1324                         && contents[offset] != '\n'; offset--)
1325                 switch (contents[offset]) {
1326                         case '=': equal_offset = offset; break;
1327                         case ']': bracket_offset = offset; break;
1328                 }
1329         if (offset > 0 && contents[offset-1] == '\\') {
1330                 offset_ = offset;
1331                 goto contline;
1332         }
1333         if (bracket_offset < equal_offset) {
1334                 *found_bracket = 1;
1335                 offset = bracket_offset+1;
1336         } else
1337                 offset++;
1338
1339         return offset;
1340 }
1341
1342 int git_config_set_in_file(const char *config_filename,
1343                         const char *key, const char *value)
1344 {
1345         return git_config_set_multivar_in_file(config_filename, key, value, NULL, 0);
1346 }
1347
1348 int git_config_set(const char *key, const char *value)
1349 {
1350         return git_config_set_multivar(key, value, NULL, 0);
1351 }
1352
1353 /*
1354  * Auxiliary function to sanity-check and split the key into the section
1355  * identifier and variable name.
1356  *
1357  * Returns 0 on success, -1 when there is an invalid character in the key and
1358  * -2 if there is no section name in the key.
1359  *
1360  * store_key - pointer to char* which will hold a copy of the key with
1361  *             lowercase section and variable name
1362  * baselen - pointer to int which will hold the length of the
1363  *           section + subsection part, can be NULL
1364  */
1365 int git_config_parse_key(const char *key, char **store_key, int *baselen_)
1366 {
1367         int i, dot, baselen;
1368         const char *last_dot = strrchr(key, '.');
1369
1370         /*
1371          * Since "key" actually contains the section name and the real
1372          * key name separated by a dot, we have to know where the dot is.
1373          */
1374
1375         if (last_dot == NULL || last_dot == key) {
1376                 error("key does not contain a section: %s", key);
1377                 return -CONFIG_NO_SECTION_OR_NAME;
1378         }
1379
1380         if (!last_dot[1]) {
1381                 error("key does not contain variable name: %s", key);
1382                 return -CONFIG_NO_SECTION_OR_NAME;
1383         }
1384
1385         baselen = last_dot - key;
1386         if (baselen_)
1387                 *baselen_ = baselen;
1388
1389         /*
1390          * Validate the key and while at it, lower case it for matching.
1391          */
1392         *store_key = xmalloc(strlen(key) + 1);
1393
1394         dot = 0;
1395         for (i = 0; key[i]; i++) {
1396                 unsigned char c = key[i];
1397                 if (c == '.')
1398                         dot = 1;
1399                 /* Leave the extended basename untouched.. */
1400                 if (!dot || i > baselen) {
1401                         if (!iskeychar(c) ||
1402                             (i == baselen + 1 && !isalpha(c))) {
1403                                 error("invalid key: %s", key);
1404                                 goto out_free_ret_1;
1405                         }
1406                         c = tolower(c);
1407                 } else if (c == '\n') {
1408                         error("invalid key (newline): %s", key);
1409                         goto out_free_ret_1;
1410                 }
1411                 (*store_key)[i] = c;
1412         }
1413         (*store_key)[i] = 0;
1414
1415         return 0;
1416
1417 out_free_ret_1:
1418         free(*store_key);
1419         *store_key = NULL;
1420         return -CONFIG_INVALID_KEY;
1421 }
1422
1423 /*
1424  * If value==NULL, unset in (remove from) config,
1425  * if value_regex!=NULL, disregard key/value pairs where value does not match.
1426  * if multi_replace==0, nothing, or only one matching key/value is replaced,
1427  *     else all matching key/values (regardless how many) are removed,
1428  *     before the new pair is written.
1429  *
1430  * Returns 0 on success.
1431  *
1432  * This function does this:
1433  *
1434  * - it locks the config file by creating ".git/config.lock"
1435  *
1436  * - it then parses the config using store_aux() as validator to find
1437  *   the position on the key/value pair to replace. If it is to be unset,
1438  *   it must be found exactly once.
1439  *
1440  * - the config file is mmap()ed and the part before the match (if any) is
1441  *   written to the lock file, then the changed part and the rest.
1442  *
1443  * - the config file is removed and the lock file rename()d to it.
1444  *
1445  */
1446 int git_config_set_multivar_in_file(const char *config_filename,
1447                                 const char *key, const char *value,
1448                                 const char *value_regex, int multi_replace)
1449 {
1450         int fd = -1, in_fd;
1451         int ret;
1452         struct lock_file *lock = NULL;
1453         char *filename_buf = NULL;
1454
1455         /* parse-key returns negative; flip the sign to feed exit(3) */
1456         ret = 0 - git_config_parse_key(key, &store.key, &store.baselen);
1457         if (ret)
1458                 goto out_free;
1459
1460         store.multi_replace = multi_replace;
1461
1462         if (!config_filename)
1463                 config_filename = filename_buf = git_pathdup("config");
1464
1465         /*
1466          * The lock serves a purpose in addition to locking: the new
1467          * contents of .git/config will be written into it.
1468          */
1469         lock = xcalloc(sizeof(struct lock_file), 1);
1470         fd = hold_lock_file_for_update(lock, config_filename, 0);
1471         if (fd < 0) {
1472                 error("could not lock config file %s: %s", config_filename, strerror(errno));
1473                 free(store.key);
1474                 ret = CONFIG_NO_LOCK;
1475                 goto out_free;
1476         }
1477
1478         /*
1479          * If .git/config does not exist yet, write a minimal version.
1480          */
1481         in_fd = open(config_filename, O_RDONLY);
1482         if ( in_fd < 0 ) {
1483                 free(store.key);
1484
1485                 if ( ENOENT != errno ) {
1486                         error("opening %s: %s", config_filename,
1487                               strerror(errno));
1488                         ret = CONFIG_INVALID_FILE; /* same as "invalid config file" */
1489                         goto out_free;
1490                 }
1491                 /* if nothing to unset, error out */
1492                 if (value == NULL) {
1493                         ret = CONFIG_NOTHING_SET;
1494                         goto out_free;
1495                 }
1496
1497                 store.key = (char *)key;
1498                 if (!store_write_section(fd, key) ||
1499                     !store_write_pair(fd, key, value))
1500                         goto write_err_out;
1501         } else {
1502                 struct stat st;
1503                 char *contents;
1504                 size_t contents_sz, copy_begin, copy_end;
1505                 int i, new_line = 0;
1506
1507                 if (value_regex == NULL)
1508                         store.value_regex = NULL;
1509                 else {
1510                         if (value_regex[0] == '!') {
1511                                 store.do_not_match = 1;
1512                                 value_regex++;
1513                         } else
1514                                 store.do_not_match = 0;
1515
1516                         store.value_regex = (regex_t*)xmalloc(sizeof(regex_t));
1517                         if (regcomp(store.value_regex, value_regex,
1518                                         REG_EXTENDED)) {
1519                                 error("invalid pattern: %s", value_regex);
1520                                 free(store.value_regex);
1521                                 ret = CONFIG_INVALID_PATTERN;
1522                                 goto out_free;
1523                         }
1524                 }
1525
1526                 store.offset[0] = 0;
1527                 store.state = START;
1528                 store.seen = 0;
1529
1530                 /*
1531                  * After this, store.offset will contain the *end* offset
1532                  * of the last match, or remain at 0 if no match was found.
1533                  * As a side effect, we make sure to transform only a valid
1534                  * existing config file.
1535                  */
1536                 if (git_config_from_file(store_aux, config_filename, NULL)) {
1537                         error("invalid config file %s", config_filename);
1538                         free(store.key);
1539                         if (store.value_regex != NULL) {
1540                                 regfree(store.value_regex);
1541                                 free(store.value_regex);
1542                         }
1543                         ret = CONFIG_INVALID_FILE;
1544                         goto out_free;
1545                 }
1546
1547                 free(store.key);
1548                 if (store.value_regex != NULL) {
1549                         regfree(store.value_regex);
1550                         free(store.value_regex);
1551                 }
1552
1553                 /* if nothing to unset, or too many matches, error out */
1554                 if ((store.seen == 0 && value == NULL) ||
1555                                 (store.seen > 1 && multi_replace == 0)) {
1556                         ret = CONFIG_NOTHING_SET;
1557                         goto out_free;
1558                 }
1559
1560                 fstat(in_fd, &st);
1561                 contents_sz = xsize_t(st.st_size);
1562                 contents = xmmap(NULL, contents_sz, PROT_READ,
1563                         MAP_PRIVATE, in_fd, 0);
1564                 close(in_fd);
1565
1566                 if (store.seen == 0)
1567                         store.seen = 1;
1568
1569                 for (i = 0, copy_begin = 0; i < store.seen; i++) {
1570                         if (store.offset[i] == 0) {
1571                                 store.offset[i] = copy_end = contents_sz;
1572                         } else if (store.state != KEY_SEEN) {
1573                                 copy_end = store.offset[i];
1574                         } else
1575                                 copy_end = find_beginning_of_line(
1576                                         contents, contents_sz,
1577                                         store.offset[i]-2, &new_line);
1578
1579                         if (copy_end > 0 && contents[copy_end-1] != '\n')
1580                                 new_line = 1;
1581
1582                         /* write the first part of the config */
1583                         if (copy_end > copy_begin) {
1584                                 if (write_in_full(fd, contents + copy_begin,
1585                                                   copy_end - copy_begin) <
1586                                     copy_end - copy_begin)
1587                                         goto write_err_out;
1588                                 if (new_line &&
1589                                     write_str_in_full(fd, "\n") != 1)
1590                                         goto write_err_out;
1591                         }
1592                         copy_begin = store.offset[i];
1593                 }
1594
1595                 /* write the pair (value == NULL means unset) */
1596                 if (value != NULL) {
1597                         if (store.state == START) {
1598                                 if (!store_write_section(fd, key))
1599                                         goto write_err_out;
1600                         }
1601                         if (!store_write_pair(fd, key, value))
1602                                 goto write_err_out;
1603                 }
1604
1605                 /* write the rest of the config */
1606                 if (copy_begin < contents_sz)
1607                         if (write_in_full(fd, contents + copy_begin,
1608                                           contents_sz - copy_begin) <
1609                             contents_sz - copy_begin)
1610                                 goto write_err_out;
1611
1612                 munmap(contents, contents_sz);
1613         }
1614
1615         if (commit_lock_file(lock) < 0) {
1616                 error("could not commit config file %s", config_filename);
1617                 ret = CONFIG_NO_WRITE;
1618                 goto out_free;
1619         }
1620
1621         /*
1622          * lock is committed, so don't try to roll it back below.
1623          * NOTE: Since lockfile.c keeps a linked list of all created
1624          * lock_file structures, it isn't safe to free(lock).  It's
1625          * better to just leave it hanging around.
1626          */
1627         lock = NULL;
1628         ret = 0;
1629
1630 out_free:
1631         if (lock)
1632                 rollback_lock_file(lock);
1633         free(filename_buf);
1634         return ret;
1635
1636 write_err_out:
1637         ret = write_error(lock->filename);
1638         goto out_free;
1639
1640 }
1641
1642 int git_config_set_multivar(const char *key, const char *value,
1643                         const char *value_regex, int multi_replace)
1644 {
1645         return git_config_set_multivar_in_file(NULL, key, value, value_regex,
1646                                                multi_replace);
1647 }
1648
1649 static int section_name_match (const char *buf, const char *name)
1650 {
1651         int i = 0, j = 0, dot = 0;
1652         if (buf[i] != '[')
1653                 return 0;
1654         for (i = 1; buf[i] && buf[i] != ']'; i++) {
1655                 if (!dot && isspace(buf[i])) {
1656                         dot = 1;
1657                         if (name[j++] != '.')
1658                                 break;
1659                         for (i++; isspace(buf[i]); i++)
1660                                 ; /* do nothing */
1661                         if (buf[i] != '"')
1662                                 break;
1663                         continue;
1664                 }
1665                 if (buf[i] == '\\' && dot)
1666                         i++;
1667                 else if (buf[i] == '"' && dot) {
1668                         for (i++; isspace(buf[i]); i++)
1669                                 ; /* do_nothing */
1670                         break;
1671                 }
1672                 if (buf[i] != name[j++])
1673                         break;
1674         }
1675         if (buf[i] == ']' && name[j] == 0) {
1676                 /*
1677                  * We match, now just find the right length offset by
1678                  * gobbling up any whitespace after it, as well
1679                  */
1680                 i++;
1681                 for (; buf[i] && isspace(buf[i]); i++)
1682                         ; /* do nothing */
1683                 return i;
1684         }
1685         return 0;
1686 }
1687
1688 static int section_name_is_ok(const char *name)
1689 {
1690         /* Empty section names are bogus. */
1691         if (!*name)
1692                 return 0;
1693
1694         /*
1695          * Before a dot, we must be alphanumeric or dash. After the first dot,
1696          * anything goes, so we can stop checking.
1697          */
1698         for (; *name && *name != '.'; name++)
1699                 if (*name != '-' && !isalnum(*name))
1700                         return 0;
1701         return 1;
1702 }
1703
1704 /* if new_name == NULL, the section is removed instead */
1705 int git_config_rename_section_in_file(const char *config_filename,
1706                                       const char *old_name, const char *new_name)
1707 {
1708         int ret = 0, remove = 0;
1709         char *filename_buf = NULL;
1710         struct lock_file *lock;
1711         int out_fd;
1712         char buf[1024];
1713         FILE *config_file;
1714
1715         if (new_name && !section_name_is_ok(new_name)) {
1716                 ret = error("invalid section name: %s", new_name);
1717                 goto out;
1718         }
1719
1720         if (!config_filename)
1721                 config_filename = filename_buf = git_pathdup("config");
1722
1723         lock = xcalloc(sizeof(struct lock_file), 1);
1724         out_fd = hold_lock_file_for_update(lock, config_filename, 0);
1725         if (out_fd < 0) {
1726                 ret = error("could not lock config file %s", config_filename);
1727                 goto out;
1728         }
1729
1730         if (!(config_file = fopen(config_filename, "rb"))) {
1731                 /* no config file means nothing to rename, no error */
1732                 goto unlock_and_out;
1733         }
1734
1735         while (fgets(buf, sizeof(buf), config_file)) {
1736                 int i;
1737                 int length;
1738                 char *output = buf;
1739                 for (i = 0; buf[i] && isspace(buf[i]); i++)
1740                         ; /* do nothing */
1741                 if (buf[i] == '[') {
1742                         /* it's a section */
1743                         int offset = section_name_match(&buf[i], old_name);
1744                         if (offset > 0) {
1745                                 ret++;
1746                                 if (new_name == NULL) {
1747                                         remove = 1;
1748                                         continue;
1749                                 }
1750                                 store.baselen = strlen(new_name);
1751                                 if (!store_write_section(out_fd, new_name)) {
1752                                         ret = write_error(lock->filename);
1753                                         goto out;
1754                                 }
1755                                 /*
1756                                  * We wrote out the new section, with
1757                                  * a newline, now skip the old
1758                                  * section's length
1759                                  */
1760                                 output += offset + i;
1761                                 if (strlen(output) > 0) {
1762                                         /*
1763                                          * More content means there's
1764                                          * a declaration to put on the
1765                                          * next line; indent with a
1766                                          * tab
1767                                          */
1768                                         output -= 1;
1769                                         output[0] = '\t';
1770                                 }
1771                         }
1772                         remove = 0;
1773                 }
1774                 if (remove)
1775                         continue;
1776                 length = strlen(output);
1777                 if (write_in_full(out_fd, output, length) != length) {
1778                         ret = write_error(lock->filename);
1779                         goto out;
1780                 }
1781         }
1782         fclose(config_file);
1783 unlock_and_out:
1784         if (commit_lock_file(lock) < 0)
1785                 ret = error("could not commit config file %s", config_filename);
1786 out:
1787         free(filename_buf);
1788         return ret;
1789 }
1790
1791 int git_config_rename_section(const char *old_name, const char *new_name)
1792 {
1793         return git_config_rename_section_in_file(NULL, old_name, new_name);
1794 }
1795
1796 /*
1797  * Call this to report error for your variable that should not
1798  * get a boolean value (i.e. "[my] var" means "true").
1799  */
1800 #undef config_error_nonbool
1801 int config_error_nonbool(const char *var)
1802 {
1803         return error("Missing value for '%s'", var);
1804 }
1805
1806 int parse_config_key(const char *var,
1807                      const char *section,
1808                      const char **subsection, int *subsection_len,
1809                      const char **key)
1810 {
1811         int section_len = strlen(section);
1812         const char *dot;
1813
1814         /* Does it start with "section." ? */
1815         if (prefixcmp(var, section) || var[section_len] != '.')
1816                 return -1;
1817
1818         /*
1819          * Find the key; we don't know yet if we have a subsection, but we must
1820          * parse backwards from the end, since the subsection may have dots in
1821          * it, too.
1822          */
1823         dot = strrchr(var, '.');
1824         *key = dot + 1;
1825
1826         /* Did we have a subsection at all? */
1827         if (dot == var + section_len) {
1828                 *subsection = NULL;
1829                 *subsection_len = 0;
1830         }
1831         else {
1832                 *subsection = var + section_len + 1;
1833                 *subsection_len = dot - *subsection;
1834         }
1835
1836         return 0;
1837 }