config.c

   1 /*
   2  * GIT - The information manager from hell
   3  *
   4  * Copyright (C) Linus Torvalds, 2005
   5  * Copyright (C) Johannes Schindelin, 2005
   6  *
   7  */
   8 #include "cache.h"
   9 #include "exec_cmd.h"
  10 #include "strbuf.h"
  11 #include "quote.h"
  12
  13 struct config_source {
  14         struct config_source *prev;
  15         union {
  16                 FILE *file;
  17                 struct config_buf {
  18                         const char *buf;
  19                         size_t len;
  20                         size_t pos;
  21                 } buf;
  22         } u;
  23         const char *name;
  24         const char *path;
  25         int die_on_error;
  26         int linenr;
  27         int eof;
  28         struct strbuf value;
  29         struct strbuf var;
  30
  31         int (*do_fgetc)(struct config_source *c);
  32         int (*do_ungetc)(int c, struct config_source *conf);
  33         long (*do_ftell)(struct config_source *c);
  34 };
  35
  36 static struct config_source *cf;
  37
  38 static int zlib_compression_seen;
  39
  40 static int config_file_fgetc(struct config_source *conf)
  41 {
  42         return fgetc(conf->u.file);
  43 }
  44
  45 static int config_file_ungetc(int c, struct config_source *conf)
  46 {
  47         return ungetc(c, conf->u.file);
  48 }
  49
  50 static long config_file_ftell(struct config_source *conf)
  51 {
  52         return ftell(conf->u.file);
  53 }
  54
  55
  56 static int config_buf_fgetc(struct config_source *conf)
  57 {
  58         if (conf->u.buf.pos < conf->u.buf.len)
  59                 return conf->u.buf.buf[conf->u.buf.pos++];
  60
  61         return EOF;
  62 }
  63
  64 static int config_buf_ungetc(int c, struct config_source *conf)
  65 {
  66         if (conf->u.buf.pos > 0)
  67                 return conf->u.buf.buf[--conf->u.buf.pos];
  68
  69         return EOF;
  70 }
  71
  72 static long config_buf_ftell(struct config_source *conf)
  73 {
  74         return conf->u.buf.pos;
  75 }
  76
  77 #define MAX_INCLUDE_DEPTH 10
  78 static const char include_depth_advice[] =
  79 "exceeded maximum include depth (%d) while including\n"
  80 "       %s\n"
  81 "from\n"
  82 "       %s\n"
  83 "Do you have circular includes?";
  84 static int handle_path_include(const char *path, struct config_include_data *inc)
  85 {
  86         int ret = 0;
  87         struct strbuf buf = STRBUF_INIT;
  88         char *expanded;
  89
  90         if (!path)
  91                 return config_error_nonbool("include.path");
  92
  93         expanded = expand_user_path(path);
  94         if (!expanded)
  95                 return error("Could not expand include path '%s'", path);
  96         path = expanded;
  97
  98         /*
  99          * Use an absolute path as-is, but interpret relative paths
 100          * based on the including config file.
 101          */
 102         if (!is_absolute_path(path)) {
 103                 char *slash;
 104
 105                 if (!cf || !cf->path)
 106                         return error("relative config includes must come from files");
 107
 108                 slash = find_last_dir_sep(cf->path);
 109                 if (slash)
 110                         strbuf_add(&buf, cf->path, slash - cf->path + 1);
 111                 strbuf_addstr(&buf, path);
 112                 path = buf.buf;
 113         }
 114
 115         if (!access_or_die(path, R_OK, 0)) {
 116                 if (++inc->depth > MAX_INCLUDE_DEPTH)
 117                         die(include_depth_advice, MAX_INCLUDE_DEPTH, path,
 118                             cf && cf->name ? cf->name : "the command line");
 119                 ret = git_config_from_file(git_config_include, path, inc);
 120                 inc->depth--;
 121         }
 122         strbuf_release(&buf);
 123         free(expanded);
 124         return ret;
 125 }
 126
 127 int git_config_include(const char *var, const char *value, void *data)
 128 {
 129         struct config_include_data *inc = data;
 130         const char *type;
 131         int ret;
 132
 133         /*
 134          * Pass along all values, including "include" directives; this makes it
 135          * possible to query information on the includes themselves.
 136          */
 137         ret = inc->fn(var, value, inc->data);
 138         if (ret < 0)
 139                 return ret;
 140
 141         type = skip_prefix(var, "include.");
 142         if (!type)
 143                 return ret;
 144
 145         if (!strcmp(type, "path"))
 146                 ret = handle_path_include(value, inc);
 147         return ret;
 148 }
 149
 150 static void lowercase(char *p)
 151 {
 152         for (; *p; p++)
 153                 *p = tolower(*p);
 154 }
 155
 156 void git_config_push_parameter(const char *text)
 157 {
 158         struct strbuf env = STRBUF_INIT;
 159         const char *old = getenv(CONFIG_DATA_ENVIRONMENT);
 160         if (old) {
 161                 strbuf_addstr(&env, old);
 162                 strbuf_addch(&env, ' ');
 163         }
 164         sq_quote_buf(&env, text);
 165         setenv(CONFIG_DATA_ENVIRONMENT, env.buf, 1);
 166         strbuf_release(&env);
 167 }
 168
 169 int git_config_parse_parameter(const char *text,
 170                                config_fn_t fn, void *data)
 171 {
 172         struct strbuf **pair;
 173         pair = strbuf_split_str(text, '=', 2);
 174         if (!pair[0])
 175                 return error("bogus config parameter: %s", text);
 176         if (pair[0]->len && pair[0]->buf[pair[0]->len - 1] == '=')
 177                 strbuf_setlen(pair[0], pair[0]->len - 1);
 178         strbuf_trim(pair[0]);
 179         if (!pair[0]->len) {
 180                 strbuf_list_free(pair);
 181                 return error("bogus config parameter: %s", text);
 182         }
 183         lowercase(pair[0]->buf);
 184         if (fn(pair[0]->buf, pair[1] ? pair[1]->buf : NULL, data) < 0) {
 185                 strbuf_list_free(pair);
 186                 return -1;
 187         }
 188         strbuf_list_free(pair);
 189         return 0;
 190 }
 191
 192 int git_config_from_parameters(config_fn_t fn, void *data)
 193 {
 194         const char *env = getenv(CONFIG_DATA_ENVIRONMENT);
 195         char *envw;
 196         const char **argv = NULL;
 197         int nr = 0, alloc = 0;
 198         int i;
 199
 200         if (!env)
 201                 return 0;
 202         /* sq_dequote will write over it */
 203         envw = xstrdup(env);
 204
 205         if (sq_dequote_to_argv(envw, &argv, &nr, &alloc) < 0) {
 206                 free(envw);
 207                 return error("bogus format in " CONFIG_DATA_ENVIRONMENT);
 208         }
 209
 210         for (i = 0; i < nr; i++) {
 211                 if (git_config_parse_parameter(argv[i], fn, data) < 0) {
 212                         free(argv);
 213                         free(envw);
 214                         return -1;
 215                 }
 216         }
 217
 218         free(argv);
 219         free(envw);
 220         return nr > 0;
 221 }
 222
 223 static int get_next_char(void)
 224 {
 225         int c = cf->do_fgetc(cf);
 226
 227         if (c == '\r') {
 228                 /* DOS like systems */
 229                 c = cf->do_fgetc(cf);
 230                 if (c != '\n') {
 231                         cf->do_ungetc(c, cf);
 232                         c = '\r';
 233                 }
 234         }
 235         if (c == '\n')
 236                 cf->linenr++;
 237         if (c == EOF) {
 238                 cf->eof = 1;
 239                 c = '\n';
 240         }
 241         return c;
 242 }
 243
 244 static char *parse_value(void)
 245 {
 246         int quote = 0, comment = 0, space = 0;
 247
 248         strbuf_reset(&cf->value);
 249         for (;;) {
 250                 int c = get_next_char();
 251                 if (c == '\n') {
 252                         if (quote) {
 253                                 cf->linenr--;
 254                                 return NULL;
 255                         }
 256                         return cf->value.buf;
 257                 }
 258                 if (comment)
 259                         continue;
 260                 if (isspace(c) && !quote) {
 261                         if (cf->value.len)
 262                                 space++;
 263                         continue;
 264                 }
 265                 if (!quote) {
 266                         if (c == ';' || c == '#') {
 267                                 comment = 1;
 268                                 continue;
 269                         }
 270                 }
 271                 for (; space; space--)
 272                         strbuf_addch(&cf->value, ' ');
 273                 if (c == '\\') {
 274                         c = get_next_char();
 275                         switch (c) {
 276                         case '\n':
 277                                 continue;
 278                         case 't':
 279                                 c = '\t';
 280                                 break;
 281                         case 'b':
 282                                 c = '\b';
 283                                 break;
 284                         case 'n':
 285                                 c = '\n';
 286                                 break;
 287                         /* Some characters escape as themselves */
 288                         case '\\': case '"':
 289                                 break;
 290                         /* Reject unknown escape sequences */
 291                         default:
 292                                 return NULL;
 293                         }
 294                         strbuf_addch(&cf->value, c);
 295                         continue;
 296                 }
 297                 if (c == '"') {
 298                         quote = 1-quote;
 299                         continue;
 300                 }
 301                 strbuf_addch(&cf->value, c);
 302         }
 303 }
 304
 305 static inline int iskeychar(int c)
 306 {
 307         return isalnum(c) || c == '-';
 308 }
 309
 310 static int get_value(config_fn_t fn, void *data, struct strbuf *name)
 311 {
 312         int c;
 313         char *value;
 314
 315         /* Get the full name */
 316         for (;;) {
 317                 c = get_next_char();
 318                 if (cf->eof)
 319                         break;
 320                 if (!iskeychar(c))
 321                         break;
 322                 strbuf_addch(name, tolower(c));
 323         }
 324
 325         while (c == ' ' || c == '\t')
 326                 c = get_next_char();
 327
 328         value = NULL;
 329         if (c != '\n') {
 330                 if (c != '=')
 331                         return -1;
 332                 value = parse_value();
 333                 if (!value)
 334                         return -1;
 335         }
 336         return fn(name->buf, value, data);
 337 }
 338
 339 static int get_extended_base_var(struct strbuf *name, int c)
 340 {
 341         do {
 342                 if (c == '\n')
 343                         goto error_incomplete_line;
 344                 c = get_next_char();
 345         } while (isspace(c));
 346
 347         /* We require the format to be '[base "extension"]' */
 348         if (c != '"')
 349                 return -1;
 350         strbuf_addch(name, '.');
 351
 352         for (;;) {
 353                 int c = get_next_char();
 354                 if (c == '\n')
 355                         goto error_incomplete_line;
 356                 if (c == '"')
 357                         break;
 358                 if (c == '\\') {
 359                         c = get_next_char();
 360                         if (c == '\n')
 361                                 goto error_incomplete_line;
 362                 }
 363                 strbuf_addch(name, c);
 364         }
 365
 366         /* Final ']' */
 367         if (get_next_char() != ']')
 368                 return -1;
 369         return 0;
 370 error_incomplete_line:
 371         cf->linenr--;
 372         return -1;
 373 }
 374
 375 static int get_base_var(struct strbuf *name)
 376 {
 377         for (;;) {
 378                 int c = get_next_char();
 379                 if (cf->eof)
 380                         return -1;
 381                 if (c == ']')
 382                         return 0;
 383                 if (isspace(c))
 384                         return get_extended_base_var(name, c);
 385                 if (!iskeychar(c) && c != '.')
 386                         return -1;
 387                 strbuf_addch(name, tolower(c));
 388         }
 389 }
 390
 391 static int git_parse_source(config_fn_t fn, void *data)
 392 {
 393         int comment = 0;
 394         int baselen = 0;
 395         struct strbuf *var = &cf->var;
 396
 397         /* U+FEFF Byte Order Mark in UTF8 */
 398         static const unsigned char *utf8_bom = (unsigned char *) "\xef\xbb\xbf";
 399         const unsigned char *bomptr = utf8_bom;
 400
 401         for (;;) {
 402                 int c = get_next_char();
 403                 if (bomptr && *bomptr) {
 404                         /* We are at the file beginning; skip UTF8-encoded BOM
 405                          * if present. Sane editors won't put this in on their
 406                          * own, but e.g. Windows Notepad will do it happily. */
 407                         if ((unsigned char) c == *bomptr) {
 408                                 bomptr++;
 409                                 continue;
 410                         } else {
 411                                 /* Do not tolerate partial BOM. */
 412                                 if (bomptr != utf8_bom)
 413                                         break;
 414                                 /* No BOM at file beginning. Cool. */
 415                                 bomptr = NULL;
 416                         }
 417                 }
 418                 if (c == '\n') {
 419                         if (cf->eof)
 420                                 return 0;
 421                         comment = 0;
 422                         continue;
 423                 }
 424                 if (comment || isspace(c))
 425                         continue;
 426                 if (c == '#' || c == ';') {
 427                         comment = 1;
 428                         continue;
 429                 }
 430                 if (c == '[') {
 431                         /* Reset prior to determining a new stem */
 432                         strbuf_reset(var);
 433                         if (get_base_var(var) < 0 || var->len < 1)
 434                                 break;
 435                         strbuf_addch(var, '.');
 436                         baselen = var->len;
 437                         continue;
 438                 }
 439                 if (!isalpha(c))
 440                         break;
 441                 /*
 442                  * Truncate the var name back to the section header
 443                  * stem prior to grabbing the suffix part of the name
 444                  * and the value.
 445                  */
 446                 strbuf_setlen(var, baselen);
 447                 strbuf_addch(var, tolower(c));
 448                 if (get_value(fn, data, var) < 0)
 449                         break;
 450         }
 451         if (cf->die_on_error)
 452                 die("bad config file line %d in %s", cf->linenr, cf->name);
 453         else
 454                 return error("bad config file line %d in %s", cf->linenr, cf->name);
 455 }
 456
 457 static int parse_unit_factor(const char *end, uintmax_t *val)
 458 {
 459         if (!*end)
 460                 return 1;
 461         else if (!strcasecmp(end, "k")) {
 462                 *val *= 1024;
 463                 return 1;
 464         }
 465         else if (!strcasecmp(end, "m")) {
 466                 *val *= 1024 * 1024;
 467                 return 1;
 468         }
 469         else if (!strcasecmp(end, "g")) {
 470                 *val *= 1024 * 1024 * 1024;
 471                 return 1;
 472         }
 473         return 0;
 474 }
 475
 476 static int git_parse_signed(const char *value, intmax_t *ret, intmax_t max)
 477 {
 478         if (value && *value) {
 479                 char *end;
 480                 intmax_t val;
 481                 uintmax_t uval;
 482                 uintmax_t factor = 1;
 483
 484                 errno = 0;
 485                 val = strtoimax(value, &end, 0);
 486                 if (errno == ERANGE)
 487                         return 0;
 488                 if (!parse_unit_factor(end, &factor)) {
 489                         errno = EINVAL;
 490                         return 0;
 491                 }
 492                 uval = abs(val);
 493                 uval *= factor;
 494                 if (uval > max || abs(val) > uval) {
 495                         errno = ERANGE;
 496                         return 0;
 497                 }
 498                 val *= factor;
 499                 *ret = val;
 500                 return 1;
 501         }
 502         errno = EINVAL;
 503         return 0;
 504 }
 505
 506 static int git_parse_unsigned(const char *value, uintmax_t *ret, uintmax_t max)
 507 {
 508         if (value && *value) {
 509                 char *end;
 510                 uintmax_t val;
 511                 uintmax_t oldval;
 512
 513                 errno = 0;
 514                 val = strtoumax(value, &end, 0);
 515                 if (errno == ERANGE)
 516                         return 0;
 517                 oldval = val;
 518                 if (!parse_unit_factor(end, &val)) {
 519                         errno = EINVAL;
 520                         return 0;
 521                 }
 522                 if (val > max || oldval > val) {
 523                         errno = ERANGE;
 524                         return 0;
 525                 }
 526                 *ret = val;
 527                 return 1;
 528         }
 529         errno = EINVAL;
 530         return 0;
 531 }
 532
 533 static int git_parse_int(const char *value, int *ret)
 534 {
 535         intmax_t tmp;
 536         if (!git_parse_signed(value, &tmp, maximum_signed_value_of_type(int)))
 537                 return 0;
 538         *ret = tmp;
 539         return 1;
 540 }
 541
 542 static int git_parse_int64(const char *value, int64_t *ret)
 543 {
 544         intmax_t tmp;
 545         if (!git_parse_signed(value, &tmp, maximum_signed_value_of_type(int64_t)))
 546                 return 0;
 547         *ret = tmp;
 548         return 1;
 549 }
 550
 551 int git_parse_ulong(const char *value, unsigned long *ret)
 552 {
 553         uintmax_t tmp;
 554         if (!git_parse_unsigned(value, &tmp, maximum_unsigned_value_of_type(long)))
 555                 return 0;
 556         *ret = tmp;
 557         return 1;
 558 }
 559
 560 NORETURN
 561 static void die_bad_number(const char *name, const char *value)
 562 {
 563         const char *reason = errno == ERANGE ?
 564                              "out of range" :
 565                              "invalid unit";
 566         if (!value)
 567                 value = "";
 568
 569         if (cf && cf->name)
 570                 die("bad numeric config value '%s' for '%s' in %s: %s",
 571                     value, name, cf->name, reason);
 572         die("bad numeric config value '%s' for '%s': %s", value, name, reason);
 573 }
 574
 575 int git_config_int(const char *name, const char *value)
 576 {
 577         int ret;
 578         if (!git_parse_int(value, &ret))
 579                 die_bad_number(name, value);
 580         return ret;
 581 }
 582
 583 int64_t git_config_int64(const char *name, const char *value)
 584 {
 585         int64_t ret;
 586         if (!git_parse_int64(value, &ret))
 587                 die_bad_number(name, value);
 588         return ret;
 589 }
 590
 591 unsigned long git_config_ulong(const char *name, const char *value)
 592 {
 593         unsigned long ret;
 594         if (!git_parse_ulong(value, &ret))
 595                 die_bad_number(name, value);
 596         return ret;
 597 }
 598
 599 static int git_config_maybe_bool_text(const char *name, const char *value)
 600 {
 601         if (!value)
 602                 return 1;
 603         if (!*value)
 604                 return 0;
 605         if (!strcasecmp(value, "true")
 606             || !strcasecmp(value, "yes")
 607             || !strcasecmp(value, "on"))
 608                 return 1;
 609         if (!strcasecmp(value, "false")
 610             || !strcasecmp(value, "no")
 611             || !strcasecmp(value, "off"))
 612                 return 0;
 613         return -1;
 614 }
 615
 616 int git_config_maybe_bool(const char *name, const char *value)
 617 {
 618         int v = git_config_maybe_bool_text(name, value);
 619         if (0 <= v)
 620                 return v;
 621         if (git_parse_int(value, &v))
 622                 return !!v;
 623         return -1;
 624 }
 625
 626 int git_config_bool_or_int(const char *name, const char *value, int *is_bool)
 627 {
 628         int v = git_config_maybe_bool_text(name, value);
 629         if (0 <= v) {
 630                 *is_bool = 1;
 631                 return v;
 632         }
 633         *is_bool = 0;
 634         return git_config_int(name, value);
 635 }
 636
 637 int git_config_bool(const char *name, const char *value)
 638 {
 639         int discard;
 640         return !!git_config_bool_or_int(name, value, &discard);
 641 }
 642
 643 int git_config_string(const char **dest, const char *var, const char *value)
 644 {
 645         if (!value)
 646                 return config_error_nonbool(var);
 647         *dest = xstrdup(value);
 648         return 0;
 649 }
 650
 651 int git_config_pathname(const char **dest, const char *var, const char *value)
 652 {
 653         if (!value)
 654                 return config_error_nonbool(var);
 655         *dest = expand_user_path(value);
 656         if (!*dest)
 657                 die("Failed to expand user dir in: '%s'", value);
 658         return 0;
 659 }
 660
 661 static int git_default_core_config(const char *var, const char *value)
 662 {
 663         /* This needs a better name */
 664         if (!strcmp(var, "core.filemode")) {
 665                 trust_executable_bit = git_config_bool(var, value);
 666                 return 0;
 667         }
 668         if (!strcmp(var, "core.trustctime")) {
 669                 trust_ctime = git_config_bool(var, value);
 670                 return 0;
 671         }
 672         if (!strcmp(var, "core.checkstat")) {
 673                 if (!strcasecmp(value, "default"))
 674                         check_stat = 1;
 675                 else if (!strcasecmp(value, "minimal"))
 676                         check_stat = 0;
 677         }
 678
 679         if (!strcmp(var, "core.quotepath")) {
 680                 quote_path_fully = git_config_bool(var, value);
 681                 return 0;
 682         }
 683
 684         if (!strcmp(var, "core.symlinks")) {
 685                 has_symlinks = git_config_bool(var, value);
 686                 return 0;
 687         }
 688
 689         if (!strcmp(var, "core.ignorecase")) {
 690                 ignore_case = git_config_bool(var, value);
 691                 return 0;
 692         }
 693
 694         if (!strcmp(var, "core.attributesfile"))
 695                 return git_config_pathname(&git_attributes_file, var, value);
 696
 697         if (!strcmp(var, "core.bare")) {
 698                 is_bare_repository_cfg = git_config_bool(var, value);
 699                 return 0;
 700         }
 701
 702         if (!strcmp(var, "core.ignorestat")) {
 703                 assume_unchanged = git_config_bool(var, value);
 704                 return 0;
 705         }
 706
 707         if (!strcmp(var, "core.prefersymlinkrefs")) {
 708                 prefer_symlink_refs = git_config_bool(var, value);
 709                 return 0;
 710         }
 711
 712         if (!strcmp(var, "core.logallrefupdates")) {
 713                 log_all_ref_updates = git_config_bool(var, value);
 714                 return 0;
 715         }
 716
 717         if (!strcmp(var, "core.warnambiguousrefs")) {
 718                 warn_ambiguous_refs = git_config_bool(var, value);
 719                 return 0;
 720         }
 721
 722         if (!strcmp(var, "core.abbrev")) {
 723                 int abbrev = git_config_int(var, value);
 724                 if (abbrev < minimum_abbrev || abbrev > 40)
 725                         return -1;
 726                 default_abbrev = abbrev;
 727                 return 0;
 728         }
 729
 730         if (!strcmp(var, "core.loosecompression")) {
 731                 int level = git_config_int(var, value);
 732                 if (level == -1)
 733                         level = Z_DEFAULT_COMPRESSION;
 734                 else if (level < 0 || level > Z_BEST_COMPRESSION)
 735                         die("bad zlib compression level %d", level);
 736                 zlib_compression_level = level;
 737                 zlib_compression_seen = 1;
 738                 return 0;
 739         }
 740
 741         if (!strcmp(var, "core.compression")) {
 742                 int level = git_config_int(var, value);
 743                 if (level == -1)
 744                         level = Z_DEFAULT_COMPRESSION;
 745                 else if (level < 0 || level > Z_BEST_COMPRESSION)
 746                         die("bad zlib compression level %d", level);
 747                 core_compression_level = level;
 748                 core_compression_seen = 1;
 749                 if (!zlib_compression_seen)
 750                         zlib_compression_level = level;
 751                 return 0;
 752         }
 753
 754         if (!strcmp(var, "core.packedgitwindowsize")) {
 755                 int pgsz_x2 = getpagesize() * 2;
 756                 packed_git_window_size = git_config_ulong(var, value);
 757
 758                 /* This value must be multiple of (pagesize * 2) */
 759                 packed_git_window_size /= pgsz_x2;
 760                 if (packed_git_window_size < 1)
 761                         packed_git_window_size = 1;
 762                 packed_git_window_size *= pgsz_x2;
 763                 return 0;
 764         }
 765
 766         if (!strcmp(var, "core.bigfilethreshold")) {
 767                 big_file_threshold = git_config_ulong(var, value);
 768                 return 0;
 769         }
 770
 771         if (!strcmp(var, "core.packedgitlimit")) {
 772                 packed_git_limit = git_config_ulong(var, value);
 773                 return 0;
 774         }
 775
 776         if (!strcmp(var, "core.deltabasecachelimit")) {
 777                 delta_base_cache_limit = git_config_ulong(var, value);
 778                 return 0;
 779         }
 780
 781         if (!strcmp(var, "core.autocrlf")) {
 782                 if (value && !strcasecmp(value, "input")) {
 783                         if (core_eol == EOL_CRLF)
 784                                 return error("core.autocrlf=input conflicts with core.eol=crlf");
 785                         auto_crlf = AUTO_CRLF_INPUT;
 786                         return 0;
 787                 }
 788                 auto_crlf = git_config_bool(var, value);
 789                 return 0;
 790         }
 791
 792         if (!strcmp(var, "core.safecrlf")) {
 793                 if (value && !strcasecmp(value, "warn")) {
 794                         safe_crlf = SAFE_CRLF_WARN;
 795                         return 0;
 796                 }
 797                 safe_crlf = git_config_bool(var, value);
 798                 return 0;
 799         }
 800
 801         if (!strcmp(var, "core.eol")) {
 802                 if (value && !strcasecmp(value, "lf"))
 803                         core_eol = EOL_LF;
 804                 else if (value && !strcasecmp(value, "crlf"))
 805                         core_eol = EOL_CRLF;
 806                 else if (value && !strcasecmp(value, "native"))
 807                         core_eol = EOL_NATIVE;
 808                 else
 809                         core_eol = EOL_UNSET;
 810                 if (core_eol == EOL_CRLF && auto_crlf == AUTO_CRLF_INPUT)
 811                         return error("core.autocrlf=input conflicts with core.eol=crlf");
 812                 return 0;
 813         }
 814
 815         if (!strcmp(var, "core.notesref")) {
 816                 notes_ref_name = xstrdup(value);
 817                 return 0;
 818         }
 819
 820         if (!strcmp(var, "core.pager"))
 821                 return git_config_string(&pager_program, var, value);
 822
 823         if (!strcmp(var, "core.editor"))
 824                 return git_config_string(&editor_program, var, value);
 825
 826         if (!strcmp(var, "core.commentchar")) {
 827                 const char *comment;
 828                 int ret = git_config_string(&comment, var, value);
 829                 if (!ret)
 830                         comment_line_char = comment[0];
 831                 return ret;
 832         }
 833
 834         if (!strcmp(var, "core.askpass"))
 835                 return git_config_string(&askpass_program, var, value);
 836
 837         if (!strcmp(var, "core.excludesfile"))
 838                 return git_config_pathname(&excludes_file, var, value);
 839
 840         if (!strcmp(var, "core.whitespace")) {
 841                 if (!value)
 842                         return config_error_nonbool(var);
 843                 whitespace_rule_cfg = parse_whitespace_rule(value);
 844                 return 0;
 845         }
 846
 847         if (!strcmp(var, "core.fsyncobjectfiles")) {
 848                 fsync_object_files = git_config_bool(var, value);
 849                 return 0;
 850         }
 851
 852         if (!strcmp(var, "core.preloadindex")) {
 853                 core_preload_index = git_config_bool(var, value);
 854                 return 0;
 855         }
 856
 857         if (!strcmp(var, "core.createobject")) {
 858                 if (!strcmp(value, "rename"))
 859                         object_creation_mode = OBJECT_CREATION_USES_RENAMES;
 860                 else if (!strcmp(value, "link"))
 861                         object_creation_mode = OBJECT_CREATION_USES_HARDLINKS;
 862                 else
 863                         die("Invalid mode for object creation: %s", value);
 864                 return 0;
 865         }
 866
 867         if (!strcmp(var, "core.sparsecheckout")) {
 868                 core_apply_sparse_checkout = git_config_bool(var, value);
 869                 return 0;
 870         }
 871
 872         if (!strcmp(var, "core.precomposeunicode")) {
 873                 precomposed_unicode = git_config_bool(var, value);
 874                 return 0;
 875         }
 876
 877         if (!strcmp(var, "core.hidedotfiles")) {
 878                 if (value && !strcasecmp(value, "dotgitonly")) {
 879                         hide_dotfiles = HIDE_DOTFILES_DOTGITONLY;
 880                         return 0;
 881                 }
 882                 hide_dotfiles = git_config_bool(var, value);
 883                 return 0;
 884         }
 885
 886         if (!strcmp(var, "core.fscache")) {
 887                 core_fscache = git_config_bool(var, value);
 888                 return 0;
 889         }
 890
 891         /* Add other config variables here and to Documentation/config.txt. */
 892         return 0;
 893 }
 894
 895 static int git_default_i18n_config(const char *var, const char *value)
 896 {
 897         if (!strcmp(var, "i18n.commitencoding"))
 898                 return git_config_string(&git_commit_encoding, var, value);
 899
 900         if (!strcmp(var, "i18n.logoutputencoding"))
 901                 return git_config_string(&git_log_output_encoding, var, value);
 902
 903         /* Add other config variables here and to Documentation/config.txt. */
 904         return 0;
 905 }
 906
 907 static int git_default_branch_config(const char *var, const char *value)
 908 {
 909         if (!strcmp(var, "branch.autosetupmerge")) {
 910                 if (value && !strcasecmp(value, "always")) {
 911                         git_branch_track = BRANCH_TRACK_ALWAYS;
 912                         return 0;
 913                 }
 914                 git_branch_track = git_config_bool(var, value);
 915                 return 0;
 916         }
 917         if (!strcmp(var, "branch.autosetuprebase")) {
 918                 if (!value)
 919                         return config_error_nonbool(var);
 920                 else if (!strcmp(value, "never"))
 921                         autorebase = AUTOREBASE_NEVER;
 922                 else if (!strcmp(value, "local"))
 923                         autorebase = AUTOREBASE_LOCAL;
 924                 else if (!strcmp(value, "remote"))
 925                         autorebase = AUTOREBASE_REMOTE;
 926                 else if (!strcmp(value, "always"))
 927                         autorebase = AUTOREBASE_ALWAYS;
 928                 else
 929                         return error("Malformed value for %s", var);
 930                 return 0;
 931         }
 932
 933         /* Add other config variables here and to Documentation/config.txt. */
 934         return 0;
 935 }
 936
 937 static int git_default_push_config(const char *var, const char *value)
 938 {
 939         if (!strcmp(var, "push.default")) {
 940                 if (!value)
 941                         return config_error_nonbool(var);
 942                 else if (!strcmp(value, "nothing"))
 943                         push_default = PUSH_DEFAULT_NOTHING;
 944                 else if (!strcmp(value, "matching"))
 945                         push_default = PUSH_DEFAULT_MATCHING;
 946                 else if (!strcmp(value, "simple"))
 947                         push_default = PUSH_DEFAULT_SIMPLE;
 948                 else if (!strcmp(value, "upstream"))
 949                         push_default = PUSH_DEFAULT_UPSTREAM;
 950                 else if (!strcmp(value, "tracking")) /* deprecated */
 951                         push_default = PUSH_DEFAULT_UPSTREAM;
 952                 else if (!strcmp(value, "current"))
 953                         push_default = PUSH_DEFAULT_CURRENT;
 954                 else {
 955                         error("Malformed value for %s: %s", var, value);
 956                         return error("Must be one of nothing, matching, simple, "
 957                                      "upstream or current.");
 958                 }
 959                 return 0;
 960         }
 961
 962         /* Add other config variables here and to Documentation/config.txt. */
 963         return 0;
 964 }
 965
 966 static int git_default_mailmap_config(const char *var, const char *value)
 967 {
 968         if (!strcmp(var, "mailmap.file"))
 969                 return git_config_string(&git_mailmap_file, var, value);
 970         if (!strcmp(var, "mailmap.blob"))
 971                 return git_config_string(&git_mailmap_blob, var, value);
 972
 973         /* Add other config variables here and to Documentation/config.txt. */
 974         return 0;
 975 }
 976
 977 int git_default_config(const char *var, const char *value, void *dummy)
 978 {
 979         if (starts_with(var, "core."))
 980                 return git_default_core_config(var, value);
 981
 982         if (starts_with(var, "user."))
 983                 return git_ident_config(var, value, dummy);
 984
 985         if (starts_with(var, "i18n."))
 986                 return git_default_i18n_config(var, value);
 987
 988         if (starts_with(var, "branch."))
 989                 return git_default_branch_config(var, value);
 990
 991         if (starts_with(var, "push."))
 992                 return git_default_push_config(var, value);
 993
 994         if (starts_with(var, "mailmap."))
 995                 return git_default_mailmap_config(var, value);
 996
 997         if (starts_with(var, "advice."))
 998                 return git_default_advice_config(var, value);
 999
1000         if (!strcmp(var, "pager.color") || !strcmp(var, "color.pager")) {
1001                 pager_use_color = git_config_bool(var,value);
1002                 return 0;
1003         }
1004
1005         if (!strcmp(var, "pack.packsizelimit")) {
1006                 pack_size_limit_cfg = git_config_ulong(var, value);
1007                 return 0;
1008         }
1009         /* Add other config variables here and to Documentation/config.txt. */
1010         return 0;
1011 }
1012
1013 /*
1014  * All source specific fields in the union, die_on_error, name and the callbacks
1015  * fgetc, ungetc, ftell of top need to be initialized before calling
1016  * this function.
1017  */
1018 static int do_config_from(struct config_source *top, config_fn_t fn, void *data)
1019 {
1020         int ret;
1021
1022         /* push config-file parsing state stack */
1023         top->prev = cf;
1024         top->linenr = 1;
1025         top->eof = 0;
1026         strbuf_init(&top->value, 1024);
1027         strbuf_init(&top->var, 1024);
1028         cf = top;
1029
1030         ret = git_parse_source(fn, data);
1031
1032         /* pop config-file parsing state stack */
1033         strbuf_release(&top->value);
1034         strbuf_release(&top->var);
1035         cf = top->prev;
1036
1037         return ret;
1038 }
1039
1040 static int do_config_from_file(config_fn_t fn,
1041                 const char *name, const char *path, FILE *f, void *data)
1042 {
1043         struct config_source top;
1044
1045         top.u.file = f;
1046         top.name = name;
1047         top.path = path;
1048         top.die_on_error = 1;
1049         top.do_fgetc = config_file_fgetc;
1050         top.do_ungetc = config_file_ungetc;
1051         top.do_ftell = config_file_ftell;
1052
1053         return do_config_from(&top, fn, data);
1054 }
1055
1056 static int git_config_from_stdin(config_fn_t fn, void *data)
1057 {
1058         return do_config_from_file(fn, "<stdin>", NULL, stdin, data);
1059 }
1060
1061 int git_config_from_file(config_fn_t fn, const char *filename, void *data)
1062 {
1063         int ret = -1;
1064         FILE *f;
1065
1066         f = fopen(filename, "r");
1067         if (f) {
1068                 ret = do_config_from_file(fn, filename, filename, f, data);
1069                 fclose(f);
1070         }
1071         return ret;
1072 }
1073
1074 int git_config_from_buf(config_fn_t fn, const char *name, const char *buf,
1075                         size_t len, void *data)
1076 {
1077         struct config_source top;
1078
1079         top.u.buf.buf = buf;
1080         top.u.buf.len = len;
1081         top.u.buf.pos = 0;
1082         top.name = name;
1083         top.path = NULL;
1084         top.die_on_error = 0;
1085         top.do_fgetc = config_buf_fgetc;
1086         top.do_ungetc = config_buf_ungetc;
1087         top.do_ftell = config_buf_ftell;
1088
1089         return do_config_from(&top, fn, data);
1090 }
1091
1092 static int git_config_from_blob_sha1(config_fn_t fn,
1093                                      const char *name,
1094                                      const unsigned char *sha1,
1095                                      void *data)
1096 {
1097         enum object_type type;
1098         char *buf;
1099         unsigned long size;
1100         int ret;
1101
1102         buf = read_sha1_file(sha1, &type, &size);
1103         if (!buf)
1104                 return error("unable to load config blob object '%s'", name);
1105         if (type != OBJ_BLOB) {
1106                 free(buf);
1107                 return error("reference '%s' does not point to a blob", name);
1108         }
1109
1110         ret = git_config_from_buf(fn, name, buf, size, data);
1111         free(buf);
1112
1113         return ret;
1114 }
1115
1116 static int git_config_from_blob_ref(config_fn_t fn,
1117                                     const char *name,
1118                                     void *data)
1119 {
1120         unsigned char sha1[20];
1121
1122         if (get_sha1(name, sha1) < 0)
1123                 return error("unable to resolve config blob '%s'", name);
1124         return git_config_from_blob_sha1(fn, name, sha1, data);
1125 }
1126
1127 const char *git_etc_gitconfig(void)
1128 {
1129         static const char *system_wide;
1130         if (!system_wide)
1131                 system_wide = system_path(ETC_GITCONFIG);
1132         return system_wide;
1133 }
1134
1135 int git_env_bool(const char *k, int def)
1136 {
1137         const char *v = getenv(k);
1138         return v ? git_config_bool(k, v) : def;
1139 }
1140
1141 int git_config_system(void)
1142 {
1143         return !git_env_bool("GIT_CONFIG_NOSYSTEM", 0);
1144 }
1145
1146 int git_config_early(config_fn_t fn, void *data, const char *repo_config)
1147 {
1148         int ret = 0, found = 0;
1149         char *xdg_config = NULL;
1150         char *user_config = NULL;
1151
1152         home_config_paths(&user_config, &xdg_config, "config");
1153
1154         if (git_config_system() && !access_or_die(git_etc_gitconfig(), R_OK, 0)) {
1155                 ret += git_config_from_file(fn, git_etc_gitconfig(),
1156                                             data);
1157                 found += 1;
1158         }
1159
1160         if (xdg_config && !access_or_die(xdg_config, R_OK, ACCESS_EACCES_OK)) {
1161                 ret += git_config_from_file(fn, xdg_config, data);
1162                 found += 1;
1163         }
1164
1165         if (user_config && !access_or_die(user_config, R_OK, ACCESS_EACCES_OK)) {
1166                 ret += git_config_from_file(fn, user_config, data);
1167                 found += 1;
1168         }
1169
1170         if (repo_config && !access_or_die(repo_config, R_OK, 0)) {
1171                 ret += git_config_from_file(fn, repo_config, data);
1172                 found += 1;
1173         }
1174
1175         switch (git_config_from_parameters(fn, data)) {
1176         case -1: /* error */
1177                 die("unable to parse command-line config");
1178                 break;
1179         case 0: /* found nothing */
1180                 break;
1181         default: /* found at least one item */
1182                 found++;
1183                 break;
1184         }
1185
1186         free(xdg_config);
1187         free(user_config);
1188         return ret == 0 ? found : ret;
1189 }
1190
1191 int git_config_with_options(config_fn_t fn, void *data,
1192                             struct git_config_source *config_source,
1193                             int respect_includes)
1194 {
1195         char *repo_config = NULL;
1196         int ret;
1197         struct config_include_data inc = CONFIG_INCLUDE_INIT;
1198
1199         if (respect_includes) {
1200                 inc.fn = fn;
1201                 inc.data = data;
1202                 fn = git_config_include;
1203                 data = &inc;
1204         }
1205
1206         /*
1207          * If we have a specific filename, use it. Otherwise, follow the
1208          * regular lookup sequence.
1209          */
1210         if (config_source && config_source->use_stdin)
1211                 return git_config_from_stdin(fn, data);
1212         else if (config_source && config_source->file)
1213                 return git_config_from_file(fn, config_source->file, data);
1214         else if (config_source && config_source->blob)
1215                 return git_config_from_blob_ref(fn, config_source->blob, data);
1216
1217         repo_config = git_pathdup("config");
1218         ret = git_config_early(fn, data, repo_config);
1219         if (repo_config)
1220                 free(repo_config);
1221         return ret;
1222 }
1223
1224 int git_config(config_fn_t fn, void *data)
1225 {
1226         return git_config_with_options(fn, data, NULL, 1);
1227 }
1228
1229 /*
1230  * Find all the stuff for git_config_set() below.
1231  */
1232
1233 static struct {
1234         int baselen;
1235         char *key;
1236         int do_not_match;
1237         regex_t *value_regex;
1238         int multi_replace;
1239         size_t *offset;
1240         unsigned int offset_alloc;
1241         enum { START, SECTION_SEEN, SECTION_END_SEEN, KEY_SEEN } state;
1242         int seen;
1243 } store;
1244
1245 static int matches(const char *key, const char *value)
1246 {
1247         return !strcmp(key, store.key) &&
1248                 (store.value_regex == NULL ||
1249                  (store.do_not_match ^
1250                   !regexec(store.value_regex, value, 0, NULL, 0)));
1251 }
1252
1253 static int store_aux(const char *key, const char *value, void *cb)
1254 {
1255         const char *ep;
1256         size_t section_len;
1257
1258         switch (store.state) {
1259         case KEY_SEEN:
1260                 if (matches(key, value)) {
1261                         if (store.seen == 1 && store.multi_replace == 0) {
1262                                 warning("%s has multiple values", key);
1263                         }
1264
1265                         ALLOC_GROW(store.offset, store.seen + 1,
1266                                    store.offset_alloc);
1267
1268                         store.offset[store.seen] = cf->do_ftell(cf);
1269                         store.seen++;
1270                 }
1271                 break;
1272         case SECTION_SEEN:
1273                 /*
1274                  * What we are looking for is in store.key (both
1275                  * section and var), and its section part is baselen
1276                  * long.  We found key (again, both section and var).
1277                  * We would want to know if this key is in the same
1278                  * section as what we are looking for.  We already
1279                  * know we are in the same section as what should
1280                  * hold store.key.
1281                  */
1282                 ep = strrchr(key, '.');
1283                 section_len = ep - key;
1284
1285                 if ((section_len != store.baselen) ||
1286                     memcmp(key, store.key, section_len+1)) {
1287                         store.state = SECTION_END_SEEN;
1288                         break;
1289                 }
1290
1291                 /*
1292                  * Do not increment matches: this is no match, but we
1293                  * just made sure we are in the desired section.
1294                  */
1295                 ALLOC_GROW(store.offset, store.seen + 1,
1296                            store.offset_alloc);
1297                 store.offset[store.seen] = cf->do_ftell(cf);
1298                 /* fallthru */
1299         case SECTION_END_SEEN:
1300         case START:
1301                 if (matches(key, value)) {
1302                         ALLOC_GROW(store.offset, store.seen + 1,
1303                                    store.offset_alloc);
1304                         store.offset[store.seen] = cf->do_ftell(cf);
1305                         store.state = KEY_SEEN;
1306                         store.seen++;
1307                 } else {
1308                         if (strrchr(key, '.') - key == store.baselen &&
1309                               !strncmp(key, store.key, store.baselen)) {
1310                                         store.state = SECTION_SEEN;
1311                                         ALLOC_GROW(store.offset,
1312                                                    store.seen + 1,
1313                                                    store.offset_alloc);
1314                                         store.offset[store.seen] = cf->do_ftell(cf);
1315                         }
1316                 }
1317         }
1318         return 0;
1319 }
1320
1321 static int write_error(const char *filename)
1322 {
1323         error("failed to write new configuration file %s", filename);
1324
1325         /* Same error code as "failed to rename". */
1326         return 4;
1327 }
1328
1329 static int store_write_section(int fd, const char *key)
1330 {
1331         const char *dot;
1332         int i, success;
1333         struct strbuf sb = STRBUF_INIT;
1334
1335         dot = memchr(key, '.', store.baselen);
1336         if (dot) {
1337                 strbuf_addf(&sb, "[%.*s \"", (int)(dot - key), key);
1338                 for (i = dot - key + 1; i < store.baselen; i++) {
1339                         if (key[i] == '"' || key[i] == '\\')
1340                                 strbuf_addch(&sb, '\\');
1341                         strbuf_addch(&sb, key[i]);
1342                 }
1343                 strbuf_addstr(&sb, "\"]\n");
1344         } else {
1345                 strbuf_addf(&sb, "[%.*s]\n", store.baselen, key);
1346         }
1347
1348         success = write_in_full(fd, sb.buf, sb.len) == sb.len;
1349         strbuf_release(&sb);
1350
1351         return success;
1352 }
1353
1354 static int store_write_pair(int fd, const char *key, const char *value)
1355 {
1356         int i, success;
1357         int length = strlen(key + store.baselen + 1);
1358         const char *quote = "";
1359         struct strbuf sb = STRBUF_INIT;
1360
1361         /*
1362          * Check to see if the value needs to be surrounded with a dq pair.
1363          * Note that problematic characters are always backslash-quoted; this
1364          * check is about not losing leading or trailing SP and strings that
1365          * follow beginning-of-comment characters (i.e. ';' and '#') by the
1366          * configuration parser.
1367          */
1368         if (value[0] == ' ')
1369                 quote = "\"";
1370         for (i = 0; value[i]; i++)
1371                 if (value[i] == ';' || value[i] == '#')
1372                         quote = "\"";
1373         if (i && value[i - 1] == ' ')
1374                 quote = "\"";
1375
1376         strbuf_addf(&sb, "\t%.*s = %s",
1377                     length, key + store.baselen + 1, quote);
1378
1379         for (i = 0; value[i]; i++)
1380                 switch (value[i]) {
1381                 case '\n':
1382                         strbuf_addstr(&sb, "\\n");
1383                         break;
1384                 case '\t':
1385                         strbuf_addstr(&sb, "\\t");
1386                         break;
1387                 case '"':
1388                 case '\\':
1389                         strbuf_addch(&sb, '\\');
1390                 default:
1391                         strbuf_addch(&sb, value[i]);
1392                         break;
1393                 }
1394         strbuf_addf(&sb, "%s\n", quote);
1395
1396         success = write_in_full(fd, sb.buf, sb.len) == sb.len;
1397         strbuf_release(&sb);
1398
1399         return success;
1400 }
1401
1402 static ssize_t find_beginning_of_line(const char *contents, size_t size,
1403         size_t offset_, int *found_bracket)
1404 {
1405         size_t equal_offset = size, bracket_offset = size;
1406         ssize_t offset;
1407
1408 contline:
1409         for (offset = offset_-2; offset > 0
1410                         && contents[offset] != '\n'; offset--)
1411                 switch (contents[offset]) {
1412                         case '=': equal_offset = offset; break;
1413                         case ']': bracket_offset = offset; break;
1414                 }
1415         if (offset > 0 && contents[offset-1] == '\\') {
1416                 offset_ = offset;
1417                 goto contline;
1418         }
1419         if (bracket_offset < equal_offset) {
1420                 *found_bracket = 1;
1421                 offset = bracket_offset+1;
1422         } else
1423                 offset++;
1424
1425         return offset;
1426 }
1427
1428 int git_config_set_in_file(const char *config_filename,
1429                         const char *key, const char *value)
1430 {
1431         return git_config_set_multivar_in_file(config_filename, key, value, NULL, 0);
1432 }
1433
1434 int git_config_set(const char *key, const char *value)
1435 {
1436         return git_config_set_multivar(key, value, NULL, 0);
1437 }
1438
1439 /*
1440  * Auxiliary function to sanity-check and split the key into the section
1441  * identifier and variable name.
1442  *
1443  * Returns 0 on success, -1 when there is an invalid character in the key and
1444  * -2 if there is no section name in the key.
1445  *
1446  * store_key - pointer to char* which will hold a copy of the key with
1447  *             lowercase section and variable name
1448  * baselen - pointer to int which will hold the length of the
1449  *           section + subsection part, can be NULL
1450  */
1451 int git_config_parse_key(const char *key, char **store_key, int *baselen_)
1452 {
1453         int i, dot, baselen;
1454         const char *last_dot = strrchr(key, '.');
1455
1456         /*
1457          * Since "key" actually contains the section name and the real
1458          * key name separated by a dot, we have to know where the dot is.
1459          */
1460
1461         if (last_dot == NULL || last_dot == key) {
1462                 error("key does not contain a section: %s", key);
1463                 return -CONFIG_NO_SECTION_OR_NAME;
1464         }
1465
1466         if (!last_dot[1]) {
1467                 error("key does not contain variable name: %s", key);
1468                 return -CONFIG_NO_SECTION_OR_NAME;
1469         }
1470
1471         baselen = last_dot - key;
1472         if (baselen_)
1473                 *baselen_ = baselen;
1474
1475         /*
1476          * Validate the key and while at it, lower case it for matching.
1477          */
1478         *store_key = xmalloc(strlen(key) + 1);
1479
1480         dot = 0;
1481         for (i = 0; key[i]; i++) {
1482                 unsigned char c = key[i];
1483                 if (c == '.')
1484                         dot = 1;
1485                 /* Leave the extended basename untouched.. */
1486                 if (!dot || i > baselen) {
1487                         if (!iskeychar(c) ||
1488                             (i == baselen + 1 && !isalpha(c))) {
1489                                 error("invalid key: %s", key);
1490                                 goto out_free_ret_1;
1491                         }
1492                         c = tolower(c);
1493                 } else if (c == '\n') {
1494                         error("invalid key (newline): %s", key);
1495                         goto out_free_ret_1;
1496                 }
1497                 (*store_key)[i] = c;
1498         }
1499         (*store_key)[i] = 0;
1500
1501         return 0;
1502
1503 out_free_ret_1:
1504         free(*store_key);
1505         *store_key = NULL;
1506         return -CONFIG_INVALID_KEY;
1507 }
1508
1509 /*
1510  * If value==NULL, unset in (remove from) config,
1511  * if value_regex!=NULL, disregard key/value pairs where value does not match.
1512  * if multi_replace==0, nothing, or only one matching key/value is replaced,
1513  *     else all matching key/values (regardless how many) are removed,
1514  *     before the new pair is written.
1515  *
1516  * Returns 0 on success.
1517  *
1518  * This function does this:
1519  *
1520  * - it locks the config file by creating ".git/config.lock"
1521  *
1522  * - it then parses the config using store_aux() as validator to find
1523  *   the position on the key/value pair to replace. If it is to be unset,
1524  *   it must be found exactly once.
1525  *
1526  * - the config file is mmap()ed and the part before the match (if any) is
1527  *   written to the lock file, then the changed part and the rest.
1528  *
1529  * - the config file is removed and the lock file rename()d to it.
1530  *
1531  */
1532 int git_config_set_multivar_in_file(const char *config_filename,
1533                                 const char *key, const char *value,
1534                                 const char *value_regex, int multi_replace)
1535 {
1536         int fd = -1, in_fd;
1537         int ret;
1538         struct lock_file *lock = NULL;
1539         char *filename_buf = NULL;
1540
1541         /* parse-key returns negative; flip the sign to feed exit(3) */
1542         ret = 0 - git_config_parse_key(key, &store.key, &store.baselen);
1543         if (ret)
1544                 goto out_free;
1545
1546         store.multi_replace = multi_replace;
1547
1548         if (!config_filename)
1549                 config_filename = filename_buf = git_pathdup("config");
1550
1551         /*
1552          * The lock serves a purpose in addition to locking: the new
1553          * contents of .git/config will be written into it.
1554          */
1555         lock = xcalloc(sizeof(struct lock_file), 1);
1556         fd = hold_lock_file_for_update(lock, config_filename, 0);
1557         if (fd < 0) {
1558                 error("could not lock config file %s: %s", config_filename, strerror(errno));
1559                 free(store.key);
1560                 ret = CONFIG_NO_LOCK;
1561                 goto out_free;
1562         }
1563
1564         /*
1565          * If .git/config does not exist yet, write a minimal version.
1566          */
1567         in_fd = open(config_filename, O_RDONLY);
1568         if ( in_fd < 0 ) {
1569                 free(store.key);
1570
1571                 if ( ENOENT != errno ) {
1572                         error("opening %s: %s", config_filename,
1573                               strerror(errno));
1574                         ret = CONFIG_INVALID_FILE; /* same as "invalid config file" */
1575                         goto out_free;
1576                 }
1577                 /* if nothing to unset, error out */
1578                 if (value == NULL) {
1579                         ret = CONFIG_NOTHING_SET;
1580                         goto out_free;
1581                 }
1582
1583                 store.key = (char *)key;
1584                 if (!store_write_section(fd, key) ||
1585                     !store_write_pair(fd, key, value))
1586                         goto write_err_out;
1587         } else {
1588                 struct stat st;
1589                 char *contents;
1590                 size_t contents_sz, copy_begin, copy_end;
1591                 int i, new_line = 0;
1592
1593                 if (value_regex == NULL)
1594                         store.value_regex = NULL;
1595                 else {
1596                         if (value_regex[0] == '!') {
1597                                 store.do_not_match = 1;
1598                                 value_regex++;
1599                         } else
1600                                 store.do_not_match = 0;
1601
1602                         store.value_regex = (regex_t*)xmalloc(sizeof(regex_t));
1603                         if (regcomp(store.value_regex, value_regex,
1604                                         REG_EXTENDED)) {
1605                                 error("invalid pattern: %s", value_regex);
1606                                 free(store.value_regex);
1607                                 ret = CONFIG_INVALID_PATTERN;
1608                                 goto out_free;
1609                         }
1610                 }
1611
1612                 ALLOC_GROW(store.offset, 1, store.offset_alloc);
1613                 store.offset[0] = 0;
1614                 store.state = START;
1615                 store.seen = 0;
1616
1617                 /*
1618                  * After this, store.offset will contain the *end* offset
1619                  * of the last match, or remain at 0 if no match was found.
1620                  * As a side effect, we make sure to transform only a valid
1621                  * existing config file.
1622                  */
1623                 if (git_config_from_file(store_aux, config_filename, NULL)) {
1624                         error("invalid config file %s", config_filename);
1625                         free(store.key);
1626                         if (store.value_regex != NULL) {
1627                                 regfree(store.value_regex);
1628                                 free(store.value_regex);
1629                         }
1630                         ret = CONFIG_INVALID_FILE;
1631                         goto out_free;
1632                 }
1633
1634                 free(store.key);
1635                 if (store.value_regex != NULL) {
1636                         regfree(store.value_regex);
1637                         free(store.value_regex);
1638                 }
1639
1640                 /* if nothing to unset, or too many matches, error out */
1641                 if ((store.seen == 0 && value == NULL) ||
1642                                 (store.seen > 1 && multi_replace == 0)) {
1643                         ret = CONFIG_NOTHING_SET;
1644                         goto out_free;
1645                 }
1646
1647                 fstat(in_fd, &st);
1648                 contents_sz = xsize_t(st.st_size);
1649                 contents = xmmap(NULL, contents_sz, PROT_READ,
1650                         MAP_PRIVATE, in_fd, 0);
1651                 close(in_fd);
1652
1653                 if (store.seen == 0)
1654                         store.seen = 1;
1655
1656                 for (i = 0, copy_begin = 0; i < store.seen; i++) {
1657                         if (store.offset[i] == 0) {
1658                                 store.offset[i] = copy_end = contents_sz;
1659                         } else if (store.state != KEY_SEEN) {
1660                                 copy_end = store.offset[i];
1661                         } else
1662                                 copy_end = find_beginning_of_line(
1663                                         contents, contents_sz,
1664                                         store.offset[i]-2, &new_line);
1665
1666                         if (copy_end > 0 && contents[copy_end-1] != '\n')
1667                                 new_line = 1;
1668
1669                         /* write the first part of the config */
1670                         if (copy_end > copy_begin) {
1671                                 if (write_in_full(fd, contents + copy_begin,
1672                                                   copy_end - copy_begin) <
1673                                     copy_end - copy_begin)
1674                                         goto write_err_out;
1675                                 if (new_line &&
1676                                     write_str_in_full(fd, "\n") != 1)
1677                                         goto write_err_out;
1678                         }
1679                         copy_begin = store.offset[i];
1680                 }
1681
1682                 /* write the pair (value == NULL means unset) */
1683                 if (value != NULL) {
1684                         if (store.state == START) {
1685                                 if (!store_write_section(fd, key))
1686                                         goto write_err_out;
1687                         }
1688                         if (!store_write_pair(fd, key, value))
1689                                 goto write_err_out;
1690                 }
1691
1692                 /* write the rest of the config */
1693                 if (copy_begin < contents_sz)
1694                         if (write_in_full(fd, contents + copy_begin,
1695                                           contents_sz - copy_begin) <
1696                             contents_sz - copy_begin)
1697                                 goto write_err_out;
1698
1699                 munmap(contents, contents_sz);
1700         }
1701
1702         if (commit_lock_file(lock) < 0) {
1703                 error("could not commit config file %s", config_filename);
1704                 ret = CONFIG_NO_WRITE;
1705                 goto out_free;
1706         }
1707
1708         /*
1709          * lock is committed, so don't try to roll it back below.
1710          * NOTE: Since lockfile.c keeps a linked list of all created
1711          * lock_file structures, it isn't safe to free(lock).  It's
1712          * better to just leave it hanging around.
1713          */
1714         lock = NULL;
1715         ret = 0;
1716
1717 out_free:
1718         if (lock)
1719                 rollback_lock_file(lock);
1720         free(filename_buf);
1721         return ret;
1722
1723 write_err_out:
1724         ret = write_error(lock->filename);
1725         goto out_free;
1726
1727 }
1728
1729 int git_config_set_multivar(const char *key, const char *value,
1730                         const char *value_regex, int multi_replace)
1731 {
1732         return git_config_set_multivar_in_file(NULL, key, value, value_regex,
1733                                                multi_replace);
1734 }
1735
1736 static int section_name_match (const char *buf, const char *name)
1737 {
1738         int i = 0, j = 0, dot = 0;
1739         if (buf[i] != '[')
1740                 return 0;
1741         for (i = 1; buf[i] && buf[i] != ']'; i++) {
1742                 if (!dot && isspace(buf[i])) {
1743                         dot = 1;
1744                         if (name[j++] != '.')
1745                                 break;
1746                         for (i++; isspace(buf[i]); i++)
1747                                 ; /* do nothing */
1748                         if (buf[i] != '"')
1749                                 break;
1750                         continue;
1751                 }
1752                 if (buf[i] == '\\' && dot)
1753                         i++;
1754                 else if (buf[i] == '"' && dot) {
1755                         for (i++; isspace(buf[i]); i++)
1756                                 ; /* do_nothing */
1757                         break;
1758                 }
1759                 if (buf[i] != name[j++])
1760                         break;
1761         }
1762         if (buf[i] == ']' && name[j] == 0) {
1763                 /*
1764                  * We match, now just find the right length offset by
1765                  * gobbling up any whitespace after it, as well
1766                  */
1767                 i++;
1768                 for (; buf[i] && isspace(buf[i]); i++)
1769                         ; /* do nothing */
1770                 return i;
1771         }
1772         return 0;
1773 }
1774
1775 static int section_name_is_ok(const char *name)
1776 {
1777         /* Empty section names are bogus. */
1778         if (!*name)
1779                 return 0;
1780
1781         /*
1782          * Before a dot, we must be alphanumeric or dash. After the first dot,
1783          * anything goes, so we can stop checking.
1784          */
1785         for (; *name && *name != '.'; name++)
1786                 if (*name != '-' && !isalnum(*name))
1787                         return 0;
1788         return 1;
1789 }
1790
1791 /* if new_name == NULL, the section is removed instead */
1792 int git_config_rename_section_in_file(const char *config_filename,
1793                                       const char *old_name, const char *new_name)
1794 {
1795         int ret = 0, remove = 0;
1796         char *filename_buf = NULL;
1797         struct lock_file *lock;
1798         int out_fd;
1799         char buf[1024];
1800         FILE *config_file;
1801
1802         if (new_name && !section_name_is_ok(new_name)) {
1803                 ret = error("invalid section name: %s", new_name);
1804                 goto out;
1805         }
1806
1807         if (!config_filename)
1808                 config_filename = filename_buf = git_pathdup("config");
1809
1810         lock = xcalloc(sizeof(struct lock_file), 1);
1811         out_fd = hold_lock_file_for_update(lock, config_filename, 0);
1812         if (out_fd < 0) {
1813                 ret = error("could not lock config file %s", config_filename);
1814                 goto out;
1815         }
1816
1817         if (!(config_file = fopen(config_filename, "rb"))) {
1818                 /* no config file means nothing to rename, no error */
1819                 goto unlock_and_out;
1820         }
1821
1822         while (fgets(buf, sizeof(buf), config_file)) {
1823                 int i;
1824                 int length;
1825                 char *output = buf;
1826                 for (i = 0; buf[i] && isspace(buf[i]); i++)
1827                         ; /* do nothing */
1828                 if (buf[i] == '[') {
1829                         /* it's a section */
1830                         int offset = section_name_match(&buf[i], old_name);
1831                         if (offset > 0) {
1832                                 ret++;
1833                                 if (new_name == NULL) {
1834                                         remove = 1;
1835                                         continue;
1836                                 }
1837                                 store.baselen = strlen(new_name);
1838                                 if (!store_write_section(out_fd, new_name)) {
1839                                         ret = write_error(lock->filename);
1840                                         goto out;
1841                                 }
1842                                 /*
1843                                  * We wrote out the new section, with
1844                                  * a newline, now skip the old
1845                                  * section's length
1846                                  */
1847                                 output += offset + i;
1848                                 if (strlen(output) > 0) {
1849                                         /*
1850                                          * More content means there's
1851                                          * a declaration to put on the
1852                                          * next line; indent with a
1853                                          * tab
1854                                          */
1855                                         output -= 1;
1856                                         output[0] = '\t';
1857                                 }
1858                         }
1859                         remove = 0;
1860                 }
1861                 if (remove)
1862                         continue;
1863                 length = strlen(output);
1864                 if (write_in_full(out_fd, output, length) != length) {
1865                         ret = write_error(lock->filename);
1866                         goto out;
1867                 }
1868         }
1869         fclose(config_file);
1870 unlock_and_out:
1871         if (commit_lock_file(lock) < 0)
1872                 ret = error("could not commit config file %s", config_filename);
1873 out:
1874         free(filename_buf);
1875         return ret;
1876 }
1877
1878 int git_config_rename_section(const char *old_name, const char *new_name)
1879 {
1880         return git_config_rename_section_in_file(NULL, old_name, new_name);
1881 }
1882
1883 /*
1884  * Call this to report error for your variable that should not
1885  * get a boolean value (i.e. "[my] var" means "true").
1886  */
1887 #undef config_error_nonbool
1888 int config_error_nonbool(const char *var)
1889 {
1890         return error("Missing value for '%s'", var);
1891 }
1892
1893 int parse_config_key(const char *var,
1894                      const char *section,
1895                      const char **subsection, int *subsection_len,
1896                      const char **key)
1897 {
1898         int section_len = strlen(section);
1899         const char *dot;
1900
1901         /* Does it start with "section." ? */
1902         if (!starts_with(var, section) || var[section_len] != '.')
1903                 return -1;
1904
1905         /*
1906          * Find the key; we don't know yet if we have a subsection, but we must
1907          * parse backwards from the end, since the subsection may have dots in
1908          * it, too.
1909          */
1910         dot = strrchr(var, '.');
1911         *key = dot + 1;
1912
1913         /* Did we have a subsection at all? */
1914         if (dot == var + section_len) {
1915                 *subsection = NULL;
1916                 *subsection_len = 0;
1917         }
1918         else {
1919                 *subsection = var + section_len + 1;
1920                 *subsection_len = dot - *subsection;
1921         }
1922
1923         return 0;
1924 }