config.c

   1 /*
   2  * GIT - The information manager from hell
   3  *
   4  * Copyright (C) Linus Torvalds, 2005
   5  * Copyright (C) Johannes Schindelin, 2005
   6  *
   7  */
   8 #include "cache.h"
   9 #include "exec_cmd.h"
  10 #include "strbuf.h"
  11 #include "quote.h"
  12
  13 struct config_source {
  14         struct config_source *prev;
  15         union {
  16                 FILE *file;
  17                 struct config_buf {
  18                         const char *buf;
  19                         size_t len;
  20                         size_t pos;
  21                 } buf;
  22         } u;
  23         const char *name;
  24         int die_on_error;
  25         int linenr;
  26         int eof;
  27         struct strbuf value;
  28         struct strbuf var;
  29
  30         int (*do_fgetc)(struct config_source *c);
  31         int (*do_ungetc)(int c, struct config_source *conf);
  32         long (*do_ftell)(struct config_source *c);
  33 };
  34
  35 static struct config_source *cf;
  36
  37 static int zlib_compression_seen;
  38
  39 static int config_file_fgetc(struct config_source *conf)
  40 {
  41         return fgetc(conf->u.file);
  42 }
  43
  44 static int config_file_ungetc(int c, struct config_source *conf)
  45 {
  46         return ungetc(c, conf->u.file);
  47 }
  48
  49 static long config_file_ftell(struct config_source *conf)
  50 {
  51         return ftell(conf->u.file);
  52 }
  53
  54
  55 static int config_buf_fgetc(struct config_source *conf)
  56 {
  57         if (conf->u.buf.pos < conf->u.buf.len)
  58                 return conf->u.buf.buf[conf->u.buf.pos++];
  59
  60         return EOF;
  61 }
  62
  63 static int config_buf_ungetc(int c, struct config_source *conf)
  64 {
  65         if (conf->u.buf.pos > 0)
  66                 return conf->u.buf.buf[--conf->u.buf.pos];
  67
  68         return EOF;
  69 }
  70
  71 static long config_buf_ftell(struct config_source *conf)
  72 {
  73         return conf->u.buf.pos;
  74 }
  75
  76 #define MAX_INCLUDE_DEPTH 10
  77 static const char include_depth_advice[] =
  78 "exceeded maximum include depth (%d) while including\n"
  79 "       %s\n"
  80 "from\n"
  81 "       %s\n"
  82 "Do you have circular includes?";
  83 static int handle_path_include(const char *path, struct config_include_data *inc)
  84 {
  85         int ret = 0;
  86         struct strbuf buf = STRBUF_INIT;
  87         char *expanded;
  88
  89         if (!path)
  90                 return config_error_nonbool("include.path");
  91
  92         expanded = expand_user_path(path);
  93         if (!expanded)
  94                 return error("Could not expand include path '%s'", path);
  95         path = expanded;
  96
  97         /*
  98          * Use an absolute path as-is, but interpret relative paths
  99          * based on the including config file.
 100          */
 101         if (!is_absolute_path(path)) {
 102                 char *slash;
 103
 104                 if (!cf || !cf->name)
 105                         return error("relative config includes must come from files");
 106
 107                 slash = find_last_dir_sep(cf->name);
 108                 if (slash)
 109                         strbuf_add(&buf, cf->name, slash - cf->name + 1);
 110                 strbuf_addstr(&buf, path);
 111                 path = buf.buf;
 112         }
 113
 114         if (!access_or_die(path, R_OK, 0)) {
 115                 if (++inc->depth > MAX_INCLUDE_DEPTH)
 116                         die(include_depth_advice, MAX_INCLUDE_DEPTH, path,
 117                             cf && cf->name ? cf->name : "the command line");
 118                 ret = git_config_from_file(git_config_include, path, inc);
 119                 inc->depth--;
 120         }
 121         strbuf_release(&buf);
 122         free(expanded);
 123         return ret;
 124 }
 125
 126 int git_config_include(const char *var, const char *value, void *data)
 127 {
 128         struct config_include_data *inc = data;
 129         const char *type;
 130         int ret;
 131
 132         /*
 133          * Pass along all values, including "include" directives; this makes it
 134          * possible to query information on the includes themselves.
 135          */
 136         ret = inc->fn(var, value, inc->data);
 137         if (ret < 0)
 138                 return ret;
 139
 140         type = skip_prefix(var, "include.");
 141         if (!type)
 142                 return ret;
 143
 144         if (!strcmp(type, "path"))
 145                 ret = handle_path_include(value, inc);
 146         return ret;
 147 }
 148
 149 static void lowercase(char *p)
 150 {
 151         for (; *p; p++)
 152                 *p = tolower(*p);
 153 }
 154
 155 void git_config_push_parameter(const char *text)
 156 {
 157         struct strbuf env = STRBUF_INIT;
 158         const char *old = getenv(CONFIG_DATA_ENVIRONMENT);
 159         if (old) {
 160                 strbuf_addstr(&env, old);
 161                 strbuf_addch(&env, ' ');
 162         }
 163         sq_quote_buf(&env, text);
 164         setenv(CONFIG_DATA_ENVIRONMENT, env.buf, 1);
 165         strbuf_release(&env);
 166 }
 167
 168 int git_config_parse_parameter(const char *text,
 169                                config_fn_t fn, void *data)
 170 {
 171         struct strbuf **pair;
 172         pair = strbuf_split_str(text, '=', 2);
 173         if (!pair[0])
 174                 return error("bogus config parameter: %s", text);
 175         if (pair[0]->len && pair[0]->buf[pair[0]->len - 1] == '=')
 176                 strbuf_setlen(pair[0], pair[0]->len - 1);
 177         strbuf_trim(pair[0]);
 178         if (!pair[0]->len) {
 179                 strbuf_list_free(pair);
 180                 return error("bogus config parameter: %s", text);
 181         }
 182         lowercase(pair[0]->buf);
 183         if (fn(pair[0]->buf, pair[1] ? pair[1]->buf : NULL, data) < 0) {
 184                 strbuf_list_free(pair);
 185                 return -1;
 186         }
 187         strbuf_list_free(pair);
 188         return 0;
 189 }
 190
 191 int git_config_from_parameters(config_fn_t fn, void *data)
 192 {
 193         const char *env = getenv(CONFIG_DATA_ENVIRONMENT);
 194         char *envw;
 195         const char **argv = NULL;
 196         int nr = 0, alloc = 0;
 197         int i;
 198
 199         if (!env)
 200                 return 0;
 201         /* sq_dequote will write over it */
 202         envw = xstrdup(env);
 203
 204         if (sq_dequote_to_argv(envw, &argv, &nr, &alloc) < 0) {
 205                 free(envw);
 206                 return error("bogus format in " CONFIG_DATA_ENVIRONMENT);
 207         }
 208
 209         for (i = 0; i < nr; i++) {
 210                 if (git_config_parse_parameter(argv[i], fn, data) < 0) {
 211                         free(argv);
 212                         free(envw);
 213                         return -1;
 214                 }
 215         }
 216
 217         free(argv);
 218         free(envw);
 219         return nr > 0;
 220 }
 221
 222 static int get_next_char(void)
 223 {
 224         int c = cf->do_fgetc(cf);
 225
 226         if (c == '\r') {
 227                 /* DOS like systems */
 228                 c = cf->do_fgetc(cf);
 229                 if (c != '\n') {
 230                         cf->do_ungetc(c, cf);
 231                         c = '\r';
 232                 }
 233         }
 234         if (c == '\n')
 235                 cf->linenr++;
 236         if (c == EOF) {
 237                 cf->eof = 1;
 238                 c = '\n';
 239         }
 240         return c;
 241 }
 242
 243 static char *parse_value(void)
 244 {
 245         int quote = 0, comment = 0, space = 0;
 246
 247         strbuf_reset(&cf->value);
 248         for (;;) {
 249                 int c = get_next_char();
 250                 if (c == '\n') {
 251                         if (quote) {
 252                                 cf->linenr--;
 253                                 return NULL;
 254                         }
 255                         return cf->value.buf;
 256                 }
 257                 if (comment)
 258                         continue;
 259                 if (isspace(c) && !quote) {
 260                         if (cf->value.len)
 261                                 space++;
 262                         continue;
 263                 }
 264                 if (!quote) {
 265                         if (c == ';' || c == '#') {
 266                                 comment = 1;
 267                                 continue;
 268                         }
 269                 }
 270                 for (; space; space--)
 271                         strbuf_addch(&cf->value, ' ');
 272                 if (c == '\\') {
 273                         c = get_next_char();
 274                         switch (c) {
 275                         case '\n':
 276                                 continue;
 277                         case 't':
 278                                 c = '\t';
 279                                 break;
 280                         case 'b':
 281                                 c = '\b';
 282                                 break;
 283                         case 'n':
 284                                 c = '\n';
 285                                 break;
 286                         /* Some characters escape as themselves */
 287                         case '\\': case '"':
 288                                 break;
 289                         /* Reject unknown escape sequences */
 290                         default:
 291                                 return NULL;
 292                         }
 293                         strbuf_addch(&cf->value, c);
 294                         continue;
 295                 }
 296                 if (c == '"') {
 297                         quote = 1-quote;
 298                         continue;
 299                 }
 300                 strbuf_addch(&cf->value, c);
 301         }
 302 }
 303
 304 static inline int iskeychar(int c)
 305 {
 306         return isalnum(c) || c == '-';
 307 }
 308
 309 static int get_value(config_fn_t fn, void *data, struct strbuf *name)
 310 {
 311         int c;
 312         char *value;
 313
 314         /* Get the full name */
 315         for (;;) {
 316                 c = get_next_char();
 317                 if (cf->eof)
 318                         break;
 319                 if (!iskeychar(c))
 320                         break;
 321                 strbuf_addch(name, tolower(c));
 322         }
 323
 324         while (c == ' ' || c == '\t')
 325                 c = get_next_char();
 326
 327         value = NULL;
 328         if (c != '\n') {
 329                 if (c != '=')
 330                         return -1;
 331                 value = parse_value();
 332                 if (!value)
 333                         return -1;
 334         }
 335         return fn(name->buf, value, data);
 336 }
 337
 338 static int get_extended_base_var(struct strbuf *name, int c)
 339 {
 340         do {
 341                 if (c == '\n')
 342                         goto error_incomplete_line;
 343                 c = get_next_char();
 344         } while (isspace(c));
 345
 346         /* We require the format to be '[base "extension"]' */
 347         if (c != '"')
 348                 return -1;
 349         strbuf_addch(name, '.');
 350
 351         for (;;) {
 352                 int c = get_next_char();
 353                 if (c == '\n')
 354                         goto error_incomplete_line;
 355                 if (c == '"')
 356                         break;
 357                 if (c == '\\') {
 358                         c = get_next_char();
 359                         if (c == '\n')
 360                                 goto error_incomplete_line;
 361                 }
 362                 strbuf_addch(name, c);
 363         }
 364
 365         /* Final ']' */
 366         if (get_next_char() != ']')
 367                 return -1;
 368         return 0;
 369 error_incomplete_line:
 370         cf->linenr--;
 371         return -1;
 372 }
 373
 374 static int get_base_var(struct strbuf *name)
 375 {
 376         for (;;) {
 377                 int c = get_next_char();
 378                 if (cf->eof)
 379                         return -1;
 380                 if (c == ']')
 381                         return 0;
 382                 if (isspace(c))
 383                         return get_extended_base_var(name, c);
 384                 if (!iskeychar(c) && c != '.')
 385                         return -1;
 386                 strbuf_addch(name, tolower(c));
 387         }
 388 }
 389
 390 static int git_parse_source(config_fn_t fn, void *data)
 391 {
 392         int comment = 0;
 393         int baselen = 0;
 394         struct strbuf *var = &cf->var;
 395
 396         /* U+FEFF Byte Order Mark in UTF8 */
 397         static const unsigned char *utf8_bom = (unsigned char *) "\xef\xbb\xbf";
 398         const unsigned char *bomptr = utf8_bom;
 399
 400         for (;;) {
 401                 int c = get_next_char();
 402                 if (bomptr && *bomptr) {
 403                         /* We are at the file beginning; skip UTF8-encoded BOM
 404                          * if present. Sane editors won't put this in on their
 405                          * own, but e.g. Windows Notepad will do it happily. */
 406                         if ((unsigned char) c == *bomptr) {
 407                                 bomptr++;
 408                                 continue;
 409                         } else {
 410                                 /* Do not tolerate partial BOM. */
 411                                 if (bomptr != utf8_bom)
 412                                         break;
 413                                 /* No BOM at file beginning. Cool. */
 414                                 bomptr = NULL;
 415                         }
 416                 }
 417                 if (c == '\n') {
 418                         if (cf->eof)
 419                                 return 0;
 420                         comment = 0;
 421                         continue;
 422                 }
 423                 if (comment || isspace(c))
 424                         continue;
 425                 if (c == '#' || c == ';') {
 426                         comment = 1;
 427                         continue;
 428                 }
 429                 if (c == '[') {
 430                         /* Reset prior to determining a new stem */
 431                         strbuf_reset(var);
 432                         if (get_base_var(var) < 0 || var->len < 1)
 433                                 break;
 434                         strbuf_addch(var, '.');
 435                         baselen = var->len;
 436                         continue;
 437                 }
 438                 if (!isalpha(c))
 439                         break;
 440                 /*
 441                  * Truncate the var name back to the section header
 442                  * stem prior to grabbing the suffix part of the name
 443                  * and the value.
 444                  */
 445                 strbuf_setlen(var, baselen);
 446                 strbuf_addch(var, tolower(c));
 447                 if (get_value(fn, data, var) < 0)
 448                         break;
 449         }
 450         if (cf->die_on_error)
 451                 die("bad config file line %d in %s", cf->linenr, cf->name);
 452         else
 453                 return error("bad config file line %d in %s", cf->linenr, cf->name);
 454 }
 455
 456 static int parse_unit_factor(const char *end, uintmax_t *val)
 457 {
 458         if (!*end)
 459                 return 1;
 460         else if (!strcasecmp(end, "k")) {
 461                 *val *= 1024;
 462                 return 1;
 463         }
 464         else if (!strcasecmp(end, "m")) {
 465                 *val *= 1024 * 1024;
 466                 return 1;
 467         }
 468         else if (!strcasecmp(end, "g")) {
 469                 *val *= 1024 * 1024 * 1024;
 470                 return 1;
 471         }
 472         return 0;
 473 }
 474
 475 static int git_parse_signed(const char *value, intmax_t *ret, intmax_t max)
 476 {
 477         if (value && *value) {
 478                 char *end;
 479                 intmax_t val;
 480                 uintmax_t uval;
 481                 uintmax_t factor = 1;
 482
 483                 errno = 0;
 484                 val = strtoimax(value, &end, 0);
 485                 if (errno == ERANGE)
 486                         return 0;
 487                 if (!parse_unit_factor(end, &factor)) {
 488                         errno = EINVAL;
 489                         return 0;
 490                 }
 491                 uval = abs(val);
 492                 uval *= factor;
 493                 if (uval > max || abs(val) > uval) {
 494                         errno = ERANGE;
 495                         return 0;
 496                 }
 497                 val *= factor;
 498                 *ret = val;
 499                 return 1;
 500         }
 501         errno = EINVAL;
 502         return 0;
 503 }
 504
 505 static int git_parse_unsigned(const char *value, uintmax_t *ret, uintmax_t max)
 506 {
 507         if (value && *value) {
 508                 char *end;
 509                 uintmax_t val;
 510                 uintmax_t oldval;
 511
 512                 errno = 0;
 513                 val = strtoumax(value, &end, 0);
 514                 if (errno == ERANGE)
 515                         return 0;
 516                 oldval = val;
 517                 if (!parse_unit_factor(end, &val)) {
 518                         errno = EINVAL;
 519                         return 0;
 520                 }
 521                 if (val > max || oldval > val) {
 522                         errno = ERANGE;
 523                         return 0;
 524                 }
 525                 *ret = val;
 526                 return 1;
 527         }
 528         errno = EINVAL;
 529         return 0;
 530 }
 531
 532 static int git_parse_int(const char *value, int *ret)
 533 {
 534         intmax_t tmp;
 535         if (!git_parse_signed(value, &tmp, maximum_signed_value_of_type(int)))
 536                 return 0;
 537         *ret = tmp;
 538         return 1;
 539 }
 540
 541 static int git_parse_int64(const char *value, int64_t *ret)
 542 {
 543         intmax_t tmp;
 544         if (!git_parse_signed(value, &tmp, maximum_signed_value_of_type(int64_t)))
 545                 return 0;
 546         *ret = tmp;
 547         return 1;
 548 }
 549
 550 int git_parse_ulong(const char *value, unsigned long *ret)
 551 {
 552         uintmax_t tmp;
 553         if (!git_parse_unsigned(value, &tmp, maximum_unsigned_value_of_type(long)))
 554                 return 0;
 555         *ret = tmp;
 556         return 1;
 557 }
 558
 559 static void die_bad_number(const char *name, const char *value)
 560 {
 561         const char *reason = errno == ERANGE ?
 562                              "out of range" :
 563                              "invalid unit";
 564         if (!value)
 565                 value = "";
 566
 567         if (cf && cf->name)
 568                 die("bad numeric config value '%s' for '%s' in %s: %s",
 569                     value, name, cf->name, reason);
 570         die("bad numeric config value '%s' for '%s': %s", value, name, reason);
 571 }
 572
 573 int git_config_int(const char *name, const char *value)
 574 {
 575         int ret;
 576         if (!git_parse_int(value, &ret))
 577                 die_bad_number(name, value);
 578         return ret;
 579 }
 580
 581 int64_t git_config_int64(const char *name, const char *value)
 582 {
 583         int64_t ret;
 584         if (!git_parse_int64(value, &ret))
 585                 die_bad_number(name, value);
 586         return ret;
 587 }
 588
 589 unsigned long git_config_ulong(const char *name, const char *value)
 590 {
 591         unsigned long ret;
 592         if (!git_parse_ulong(value, &ret))
 593                 die_bad_number(name, value);
 594         return ret;
 595 }
 596
 597 static int git_config_maybe_bool_text(const char *name, const char *value)
 598 {
 599         if (!value)
 600                 return 1;
 601         if (!*value)
 602                 return 0;
 603         if (!strcasecmp(value, "true")
 604             || !strcasecmp(value, "yes")
 605             || !strcasecmp(value, "on"))
 606                 return 1;
 607         if (!strcasecmp(value, "false")
 608             || !strcasecmp(value, "no")
 609             || !strcasecmp(value, "off"))
 610                 return 0;
 611         return -1;
 612 }
 613
 614 int git_config_maybe_bool(const char *name, const char *value)
 615 {
 616         int v = git_config_maybe_bool_text(name, value);
 617         if (0 <= v)
 618                 return v;
 619         if (git_parse_int(value, &v))
 620                 return !!v;
 621         return -1;
 622 }
 623
 624 int git_config_bool_or_int(const char *name, const char *value, int *is_bool)
 625 {
 626         int v = git_config_maybe_bool_text(name, value);
 627         if (0 <= v) {
 628                 *is_bool = 1;
 629                 return v;
 630         }
 631         *is_bool = 0;
 632         return git_config_int(name, value);
 633 }
 634
 635 int git_config_bool(const char *name, const char *value)
 636 {
 637         int discard;
 638         return !!git_config_bool_or_int(name, value, &discard);
 639 }
 640
 641 int git_config_string(const char **dest, const char *var, const char *value)
 642 {
 643         if (!value)
 644                 return config_error_nonbool(var);
 645         *dest = xstrdup(value);
 646         return 0;
 647 }
 648
 649 int git_config_pathname(const char **dest, const char *var, const char *value)
 650 {
 651         if (!value)
 652                 return config_error_nonbool(var);
 653         *dest = expand_user_path(value);
 654         if (!*dest)
 655                 die("Failed to expand user dir in: '%s'", value);
 656         return 0;
 657 }
 658
 659 static int git_default_core_config(const char *var, const char *value)
 660 {
 661         /* This needs a better name */
 662         if (!strcmp(var, "core.filemode")) {
 663                 trust_executable_bit = git_config_bool(var, value);
 664                 return 0;
 665         }
 666         if (!strcmp(var, "core.trustctime")) {
 667                 trust_ctime = git_config_bool(var, value);
 668                 return 0;
 669         }
 670         if (!strcmp(var, "core.statinfo") ||
 671             !strcmp(var, "core.checkstat")) {
 672                 /*
 673                  * NEEDSWORK: statinfo was a typo in v1.8.2 that has
 674                  * never been advertised.  we will remove it at Git
 675                  * 2.0 boundary.
 676                  */
 677                 if (!strcmp(var, "core.statinfo")) {
 678                         static int warned;
 679                         if (!warned++) {
 680                                 warning("'core.statinfo' will be removed in Git 2.0; "
 681                                         "use 'core.checkstat' instead.");
 682                         }
 683                 }
 684                 if (!strcasecmp(value, "default"))
 685                         check_stat = 1;
 686                 else if (!strcasecmp(value, "minimal"))
 687                         check_stat = 0;
 688         }
 689
 690         if (!strcmp(var, "core.quotepath")) {
 691                 quote_path_fully = git_config_bool(var, value);
 692                 return 0;
 693         }
 694
 695         if (!strcmp(var, "core.symlinks")) {
 696                 has_symlinks = git_config_bool(var, value);
 697                 return 0;
 698         }
 699
 700         if (!strcmp(var, "core.ignorecase")) {
 701                 ignore_case = git_config_bool(var, value);
 702                 return 0;
 703         }
 704
 705         if (!strcmp(var, "core.attributesfile"))
 706                 return git_config_pathname(&git_attributes_file, var, value);
 707
 708         if (!strcmp(var, "core.bare")) {
 709                 is_bare_repository_cfg = git_config_bool(var, value);
 710                 return 0;
 711         }
 712
 713         if (!strcmp(var, "core.ignorestat")) {
 714                 assume_unchanged = git_config_bool(var, value);
 715                 return 0;
 716         }
 717
 718         if (!strcmp(var, "core.prefersymlinkrefs")) {
 719                 prefer_symlink_refs = git_config_bool(var, value);
 720                 return 0;
 721         }
 722
 723         if (!strcmp(var, "core.logallrefupdates")) {
 724                 log_all_ref_updates = git_config_bool(var, value);
 725                 return 0;
 726         }
 727
 728         if (!strcmp(var, "core.warnambiguousrefs")) {
 729                 warn_ambiguous_refs = git_config_bool(var, value);
 730                 return 0;
 731         }
 732
 733         if (!strcmp(var, "core.abbrev")) {
 734                 int abbrev = git_config_int(var, value);
 735                 if (abbrev < minimum_abbrev || abbrev > 40)
 736                         return -1;
 737                 default_abbrev = abbrev;
 738                 return 0;
 739         }
 740
 741         if (!strcmp(var, "core.loosecompression")) {
 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                 zlib_compression_level = level;
 748                 zlib_compression_seen = 1;
 749                 return 0;
 750         }
 751
 752         if (!strcmp(var, "core.compression")) {
 753                 int level = git_config_int(var, value);
 754                 if (level == -1)
 755                         level = Z_DEFAULT_COMPRESSION;
 756                 else if (level < 0 || level > Z_BEST_COMPRESSION)
 757                         die("bad zlib compression level %d", level);
 758                 core_compression_level = level;
 759                 core_compression_seen = 1;
 760                 if (!zlib_compression_seen)
 761                         zlib_compression_level = level;
 762                 return 0;
 763         }
 764
 765         if (!strcmp(var, "core.packedgitwindowsize")) {
 766                 int pgsz_x2 = getpagesize() * 2;
 767                 packed_git_window_size = git_config_ulong(var, value);
 768
 769                 /* This value must be multiple of (pagesize * 2) */
 770                 packed_git_window_size /= pgsz_x2;
 771                 if (packed_git_window_size < 1)
 772                         packed_git_window_size = 1;
 773                 packed_git_window_size *= pgsz_x2;
 774                 return 0;
 775         }
 776
 777         if (!strcmp(var, "core.bigfilethreshold")) {
 778                 big_file_threshold = git_config_ulong(var, value);
 779                 return 0;
 780         }
 781
 782         if (!strcmp(var, "core.packedgitlimit")) {
 783                 packed_git_limit = git_config_ulong(var, value);
 784                 return 0;
 785         }
 786
 787         if (!strcmp(var, "core.deltabasecachelimit")) {
 788                 delta_base_cache_limit = git_config_ulong(var, value);
 789                 return 0;
 790         }
 791
 792         if (!strcmp(var, "core.autocrlf")) {
 793                 if (value && !strcasecmp(value, "input")) {
 794                         if (core_eol == EOL_CRLF)
 795                                 return error("core.autocrlf=input conflicts with core.eol=crlf");
 796                         auto_crlf = AUTO_CRLF_INPUT;
 797                         return 0;
 798                 }
 799                 auto_crlf = git_config_bool(var, value);
 800                 return 0;
 801         }
 802
 803         if (!strcmp(var, "core.safecrlf")) {
 804                 if (value && !strcasecmp(value, "warn")) {
 805                         safe_crlf = SAFE_CRLF_WARN;
 806                         return 0;
 807                 }
 808                 safe_crlf = git_config_bool(var, value);
 809                 return 0;
 810         }
 811
 812         if (!strcmp(var, "core.eol")) {
 813                 if (value && !strcasecmp(value, "lf"))
 814                         core_eol = EOL_LF;
 815                 else if (value && !strcasecmp(value, "crlf"))
 816                         core_eol = EOL_CRLF;
 817                 else if (value && !strcasecmp(value, "native"))
 818                         core_eol = EOL_NATIVE;
 819                 else
 820                         core_eol = EOL_UNSET;
 821                 if (core_eol == EOL_CRLF && auto_crlf == AUTO_CRLF_INPUT)
 822                         return error("core.autocrlf=input conflicts with core.eol=crlf");
 823                 return 0;
 824         }
 825
 826         if (!strcmp(var, "core.notesref")) {
 827                 notes_ref_name = xstrdup(value);
 828                 return 0;
 829         }
 830
 831         if (!strcmp(var, "core.pager"))
 832                 return git_config_string(&pager_program, var, value);
 833
 834         if (!strcmp(var, "core.editor"))
 835                 return git_config_string(&editor_program, var, value);
 836
 837         if (!strcmp(var, "core.commentchar")) {
 838                 const char *comment;
 839                 int ret = git_config_string(&comment, var, value);
 840                 if (!ret)
 841                         comment_line_char = comment[0];
 842                 return ret;
 843         }
 844
 845         if (!strcmp(var, "core.askpass"))
 846                 return git_config_string(&askpass_program, var, value);
 847
 848         if (!strcmp(var, "core.excludesfile"))
 849                 return git_config_pathname(&excludes_file, var, value);
 850
 851         if (!strcmp(var, "core.whitespace")) {
 852                 if (!value)
 853                         return config_error_nonbool(var);
 854                 whitespace_rule_cfg = parse_whitespace_rule(value);
 855                 return 0;
 856         }
 857
 858         if (!strcmp(var, "core.fsyncobjectfiles")) {
 859                 fsync_object_files = git_config_bool(var, value);
 860                 return 0;
 861         }
 862
 863         if (!strcmp(var, "core.preloadindex")) {
 864                 core_preload_index = git_config_bool(var, value);
 865                 return 0;
 866         }
 867
 868         if (!strcmp(var, "core.createobject")) {
 869                 if (!strcmp(value, "rename"))
 870                         object_creation_mode = OBJECT_CREATION_USES_RENAMES;
 871                 else if (!strcmp(value, "link"))
 872                         object_creation_mode = OBJECT_CREATION_USES_HARDLINKS;
 873                 else
 874                         die("Invalid mode for object creation: %s", value);
 875                 return 0;
 876         }
 877
 878         if (!strcmp(var, "core.sparsecheckout")) {
 879                 core_apply_sparse_checkout = git_config_bool(var, value);
 880                 return 0;
 881         }
 882
 883         if (!strcmp(var, "core.precomposeunicode")) {
 884                 precomposed_unicode = git_config_bool(var, value);
 885                 return 0;
 886         }
 887
 888         if (!strcmp(var, "core.hidedotfiles")) {
 889                 if (value && !strcasecmp(value, "dotgitonly")) {
 890                         hide_dotfiles = HIDE_DOTFILES_DOTGITONLY;
 891                         return 0;
 892                 }
 893                 hide_dotfiles = git_config_bool(var, value);
 894                 return 0;
 895         }
 896
 897         /* Add other config variables here and to Documentation/config.txt. */
 898         return 0;
 899 }
 900
 901 static int git_default_i18n_config(const char *var, const char *value)
 902 {
 903         if (!strcmp(var, "i18n.commitencoding"))
 904                 return git_config_string(&git_commit_encoding, var, value);
 905
 906         if (!strcmp(var, "i18n.logoutputencoding"))
 907                 return git_config_string(&git_log_output_encoding, var, value);
 908
 909         /* Add other config variables here and to Documentation/config.txt. */
 910         return 0;
 911 }
 912
 913 static int git_default_branch_config(const char *var, const char *value)
 914 {
 915         if (!strcmp(var, "branch.autosetupmerge")) {
 916                 if (value && !strcasecmp(value, "always")) {
 917                         git_branch_track = BRANCH_TRACK_ALWAYS;
 918                         return 0;
 919                 }
 920                 git_branch_track = git_config_bool(var, value);
 921                 return 0;
 922         }
 923         if (!strcmp(var, "branch.autosetuprebase")) {
 924                 if (!value)
 925                         return config_error_nonbool(var);
 926                 else if (!strcmp(value, "never"))
 927                         autorebase = AUTOREBASE_NEVER;
 928                 else if (!strcmp(value, "local"))
 929                         autorebase = AUTOREBASE_LOCAL;
 930                 else if (!strcmp(value, "remote"))
 931                         autorebase = AUTOREBASE_REMOTE;
 932                 else if (!strcmp(value, "always"))
 933                         autorebase = AUTOREBASE_ALWAYS;
 934                 else
 935                         return error("Malformed value for %s", var);
 936                 return 0;
 937         }
 938
 939         /* Add other config variables here and to Documentation/config.txt. */
 940         return 0;
 941 }
 942
 943 static int git_default_push_config(const char *var, const char *value)
 944 {
 945         if (!strcmp(var, "push.default")) {
 946                 if (!value)
 947                         return config_error_nonbool(var);
 948                 else if (!strcmp(value, "nothing"))
 949                         push_default = PUSH_DEFAULT_NOTHING;
 950                 else if (!strcmp(value, "matching"))
 951                         push_default = PUSH_DEFAULT_MATCHING;
 952                 else if (!strcmp(value, "simple"))
 953                         push_default = PUSH_DEFAULT_SIMPLE;
 954                 else if (!strcmp(value, "upstream"))
 955                         push_default = PUSH_DEFAULT_UPSTREAM;
 956                 else if (!strcmp(value, "tracking")) /* deprecated */
 957                         push_default = PUSH_DEFAULT_UPSTREAM;
 958                 else if (!strcmp(value, "current"))
 959                         push_default = PUSH_DEFAULT_CURRENT;
 960                 else {
 961                         error("Malformed value for %s: %s", var, value);
 962                         return error("Must be one of nothing, matching, simple, "
 963                                      "upstream or current.");
 964                 }
 965                 return 0;
 966         }
 967
 968         /* Add other config variables here and to Documentation/config.txt. */
 969         return 0;
 970 }
 971
 972 static int git_default_mailmap_config(const char *var, const char *value)
 973 {
 974         if (!strcmp(var, "mailmap.file"))
 975                 return git_config_string(&git_mailmap_file, var, value);
 976         if (!strcmp(var, "mailmap.blob"))
 977                 return git_config_string(&git_mailmap_blob, var, value);
 978
 979         /* Add other config variables here and to Documentation/config.txt. */
 980         return 0;
 981 }
 982
 983 int git_default_config(const char *var, const char *value, void *dummy)
 984 {
 985         if (starts_with(var, "core."))
 986                 return git_default_core_config(var, value);
 987
 988         if (starts_with(var, "user."))
 989                 return git_ident_config(var, value, dummy);
 990
 991         if (starts_with(var, "i18n."))
 992                 return git_default_i18n_config(var, value);
 993
 994         if (starts_with(var, "branch."))
 995                 return git_default_branch_config(var, value);
 996
 997         if (starts_with(var, "push."))
 998                 return git_default_push_config(var, value);
 999
1000         if (starts_with(var, "mailmap."))
1001                 return git_default_mailmap_config(var, value);
1002
1003         if (starts_with(var, "advice."))
1004                 return git_default_advice_config(var, value);
1005
1006         if (!strcmp(var, "pager.color") || !strcmp(var, "color.pager")) {
1007                 pager_use_color = git_config_bool(var,value);
1008                 return 0;
1009         }
1010
1011         if (!strcmp(var, "pack.packsizelimit")) {
1012                 pack_size_limit_cfg = git_config_ulong(var, value);
1013                 return 0;
1014         }
1015         /* Add other config variables here and to Documentation/config.txt. */
1016         return 0;
1017 }
1018
1019 /*
1020  * All source specific fields in the union, die_on_error, name and the callbacks
1021  * fgetc, ungetc, ftell of top need to be initialized before calling
1022  * this function.
1023  */
1024 static int do_config_from(struct config_source *top, config_fn_t fn, void *data)
1025 {
1026         int ret;
1027
1028         /* push config-file parsing state stack */
1029         top->prev = cf;
1030         top->linenr = 1;
1031         top->eof = 0;
1032         strbuf_init(&top->value, 1024);
1033         strbuf_init(&top->var, 1024);
1034         cf = top;
1035
1036         ret = git_parse_source(fn, data);
1037
1038         /* pop config-file parsing state stack */
1039         strbuf_release(&top->value);
1040         strbuf_release(&top->var);
1041         cf = top->prev;
1042
1043         return ret;
1044 }
1045
1046 int git_config_from_file(config_fn_t fn, const char *filename, void *data)
1047 {
1048         int ret;
1049         FILE *f = fopen(filename, "r");
1050
1051         ret = -1;
1052         if (f) {
1053                 struct config_source top;
1054
1055                 top.u.file = f;
1056                 top.name = filename;
1057                 top.die_on_error = 1;
1058                 top.do_fgetc = config_file_fgetc;
1059                 top.do_ungetc = config_file_ungetc;
1060                 top.do_ftell = config_file_ftell;
1061
1062                 ret = do_config_from(&top, fn, data);
1063
1064                 fclose(f);
1065         }
1066         return ret;
1067 }
1068
1069 int git_config_from_buf(config_fn_t fn, const char *name, const char *buf,
1070                         size_t len, void *data)
1071 {
1072         struct config_source top;
1073
1074         top.u.buf.buf = buf;
1075         top.u.buf.len = len;
1076         top.u.buf.pos = 0;
1077         top.name = name;
1078         top.die_on_error = 0;
1079         top.do_fgetc = config_buf_fgetc;
1080         top.do_ungetc = config_buf_ungetc;
1081         top.do_ftell = config_buf_ftell;
1082
1083         return do_config_from(&top, fn, data);
1084 }
1085
1086 static int git_config_from_blob_sha1(config_fn_t fn,
1087                                      const char *name,
1088                                      const unsigned char *sha1,
1089                                      void *data)
1090 {
1091         enum object_type type;
1092         char *buf;
1093         unsigned long size;
1094         int ret;
1095
1096         buf = read_sha1_file(sha1, &type, &size);
1097         if (!buf)
1098                 return error("unable to load config blob object '%s'", name);
1099         if (type != OBJ_BLOB) {
1100                 free(buf);
1101                 return error("reference '%s' does not point to a blob", name);
1102         }
1103
1104         ret = git_config_from_buf(fn, name, buf, size, data);
1105         free(buf);
1106
1107         return ret;
1108 }
1109
1110 static int git_config_from_blob_ref(config_fn_t fn,
1111                                     const char *name,
1112                                     void *data)
1113 {
1114         unsigned char sha1[20];
1115
1116         if (get_sha1(name, sha1) < 0)
1117                 return error("unable to resolve config blob '%s'", name);
1118         return git_config_from_blob_sha1(fn, name, sha1, data);
1119 }
1120
1121 const char *git_etc_gitconfig(void)
1122 {
1123         static const char *system_wide;
1124         if (!system_wide)
1125                 system_wide = system_path(ETC_GITCONFIG);
1126         return system_wide;
1127 }
1128
1129 int git_env_bool(const char *k, int def)
1130 {
1131         const char *v = getenv(k);
1132         return v ? git_config_bool(k, v) : def;
1133 }
1134
1135 int git_config_system(void)
1136 {
1137         return !git_env_bool("GIT_CONFIG_NOSYSTEM", 0);
1138 }
1139
1140 int git_config_early(config_fn_t fn, void *data, const char *repo_config)
1141 {
1142         int ret = 0, found = 0;
1143         char *xdg_config = NULL;
1144         char *user_config = NULL;
1145
1146         home_config_paths(&user_config, &xdg_config, "config");
1147
1148         if (git_config_system() && !access_or_die(git_etc_gitconfig(), R_OK, 0)) {
1149                 ret += git_config_from_file(fn, git_etc_gitconfig(),
1150                                             data);
1151                 found += 1;
1152         }
1153
1154         if (xdg_config && !access_or_die(xdg_config, R_OK, ACCESS_EACCES_OK)) {
1155                 ret += git_config_from_file(fn, xdg_config, data);
1156                 found += 1;
1157         }
1158
1159         if (user_config && !access_or_die(user_config, R_OK, ACCESS_EACCES_OK)) {
1160                 ret += git_config_from_file(fn, user_config, data);
1161                 found += 1;
1162         }
1163
1164         if (repo_config && !access_or_die(repo_config, R_OK, 0)) {
1165                 ret += git_config_from_file(fn, repo_config, data);
1166                 found += 1;
1167         }
1168
1169         switch (git_config_from_parameters(fn, data)) {
1170         case -1: /* error */
1171                 die("unable to parse command-line config");
1172                 break;
1173         case 0: /* found nothing */
1174                 break;
1175         default: /* found at least one item */
1176                 found++;
1177                 break;
1178         }
1179
1180         free(xdg_config);
1181         free(user_config);
1182         return ret == 0 ? found : ret;
1183 }
1184
1185 int git_config_with_options(config_fn_t fn, void *data,
1186                             const char *filename,
1187                             const char *blob_ref,
1188                             int respect_includes)
1189 {
1190         char *repo_config = NULL;
1191         int ret;
1192         struct config_include_data inc = CONFIG_INCLUDE_INIT;
1193
1194         if (respect_includes) {
1195                 inc.fn = fn;
1196                 inc.data = data;
1197                 fn = git_config_include;
1198                 data = &inc;
1199         }
1200
1201         /*
1202          * If we have a specific filename, use it. Otherwise, follow the
1203          * regular lookup sequence.
1204          */
1205         if (filename)
1206                 return git_config_from_file(fn, filename, data);
1207         else if (blob_ref)
1208                 return git_config_from_blob_ref(fn, blob_ref, data);
1209
1210         repo_config = git_pathdup("config");
1211         ret = git_config_early(fn, data, repo_config);
1212         if (repo_config)
1213                 free(repo_config);
1214         return ret;
1215 }
1216
1217 int git_config(config_fn_t fn, void *data)
1218 {
1219         return git_config_with_options(fn, data, NULL, NULL, 1);
1220 }
1221
1222 /*
1223  * Find all the stuff for git_config_set() below.
1224  */
1225
1226 static struct {
1227         int baselen;
1228         char *key;
1229         int do_not_match;
1230         regex_t *value_regex;
1231         int multi_replace;
1232         size_t *offset;
1233         unsigned int offset_alloc;
1234         enum { START, SECTION_SEEN, SECTION_END_SEEN, KEY_SEEN } state;
1235         int seen;
1236 } store;
1237
1238 static int matches(const char *key, const char *value)
1239 {
1240         return !strcmp(key, store.key) &&
1241                 (store.value_regex == NULL ||
1242                  (store.do_not_match ^
1243                   !regexec(store.value_regex, value, 0, NULL, 0)));
1244 }
1245
1246 static int store_aux(const char *key, const char *value, void *cb)
1247 {
1248         const char *ep;
1249         size_t section_len;
1250
1251         switch (store.state) {
1252         case KEY_SEEN:
1253                 if (matches(key, value)) {
1254                         if (store.seen == 1 && store.multi_replace == 0) {
1255                                 warning("%s has multiple values", key);
1256                         }
1257
1258                         ALLOC_GROW(store.offset, store.seen + 1,
1259                                    store.offset_alloc);
1260
1261                         store.offset[store.seen] = cf->do_ftell(cf);
1262                         store.seen++;
1263                 }
1264                 break;
1265         case SECTION_SEEN:
1266                 /*
1267                  * What we are looking for is in store.key (both
1268                  * section and var), and its section part is baselen
1269                  * long.  We found key (again, both section and var).
1270                  * We would want to know if this key is in the same
1271                  * section as what we are looking for.  We already
1272                  * know we are in the same section as what should
1273                  * hold store.key.
1274                  */
1275                 ep = strrchr(key, '.');
1276                 section_len = ep - key;
1277
1278                 if ((section_len != store.baselen) ||
1279                     memcmp(key, store.key, section_len+1)) {
1280                         store.state = SECTION_END_SEEN;
1281                         break;
1282                 }
1283
1284                 /*
1285                  * Do not increment matches: this is no match, but we
1286                  * just made sure we are in the desired section.
1287                  */
1288                 ALLOC_GROW(store.offset, store.seen + 1,
1289                            store.offset_alloc);
1290                 store.offset[store.seen] = cf->do_ftell(cf);
1291                 /* fallthru */
1292         case SECTION_END_SEEN:
1293         case START:
1294                 if (matches(key, value)) {
1295                         ALLOC_GROW(store.offset, store.seen + 1,
1296                                    store.offset_alloc);
1297                         store.offset[store.seen] = cf->do_ftell(cf);
1298                         store.state = KEY_SEEN;
1299                         store.seen++;
1300                 } else {
1301                         if (strrchr(key, '.') - key == store.baselen &&
1302                               !strncmp(key, store.key, store.baselen)) {
1303                                         store.state = SECTION_SEEN;
1304                                         ALLOC_GROW(store.offset,
1305                                                    store.seen + 1,
1306                                                    store.offset_alloc);
1307                                         store.offset[store.seen] = cf->do_ftell(cf);
1308                         }
1309                 }
1310         }
1311         return 0;
1312 }
1313
1314 static int write_error(const char *filename)
1315 {
1316         error("failed to write new configuration file %s", filename);
1317
1318         /* Same error code as "failed to rename". */
1319         return 4;
1320 }
1321
1322 static int store_write_section(int fd, const char *key)
1323 {
1324         const char *dot;
1325         int i, success;
1326         struct strbuf sb = STRBUF_INIT;
1327
1328         dot = memchr(key, '.', store.baselen);
1329         if (dot) {
1330                 strbuf_addf(&sb, "[%.*s \"", (int)(dot - key), key);
1331                 for (i = dot - key + 1; i < store.baselen; i++) {
1332                         if (key[i] == '"' || key[i] == '\\')
1333                                 strbuf_addch(&sb, '\\');
1334                         strbuf_addch(&sb, key[i]);
1335                 }
1336                 strbuf_addstr(&sb, "\"]\n");
1337         } else {
1338                 strbuf_addf(&sb, "[%.*s]\n", store.baselen, key);
1339         }
1340
1341         success = write_in_full(fd, sb.buf, sb.len) == sb.len;
1342         strbuf_release(&sb);
1343
1344         return success;
1345 }
1346
1347 static int store_write_pair(int fd, const char *key, const char *value)
1348 {
1349         int i, success;
1350         int length = strlen(key + store.baselen + 1);
1351         const char *quote = "";
1352         struct strbuf sb = STRBUF_INIT;
1353
1354         /*
1355          * Check to see if the value needs to be surrounded with a dq pair.
1356          * Note that problematic characters are always backslash-quoted; this
1357          * check is about not losing leading or trailing SP and strings that
1358          * follow beginning-of-comment characters (i.e. ';' and '#') by the
1359          * configuration parser.
1360          */
1361         if (value[0] == ' ')
1362                 quote = "\"";
1363         for (i = 0; value[i]; i++)
1364                 if (value[i] == ';' || value[i] == '#')
1365                         quote = "\"";
1366         if (i && value[i - 1] == ' ')
1367                 quote = "\"";
1368
1369         strbuf_addf(&sb, "\t%.*s = %s",
1370                     length, key + store.baselen + 1, quote);
1371
1372         for (i = 0; value[i]; i++)
1373                 switch (value[i]) {
1374                 case '\n':
1375                         strbuf_addstr(&sb, "\\n");
1376                         break;
1377                 case '\t':
1378                         strbuf_addstr(&sb, "\\t");
1379                         break;
1380                 case '"':
1381                 case '\\':
1382                         strbuf_addch(&sb, '\\');
1383                 default:
1384                         strbuf_addch(&sb, value[i]);
1385                         break;
1386                 }
1387         strbuf_addf(&sb, "%s\n", quote);
1388
1389         success = write_in_full(fd, sb.buf, sb.len) == sb.len;
1390         strbuf_release(&sb);
1391
1392         return success;
1393 }
1394
1395 static ssize_t find_beginning_of_line(const char *contents, size_t size,
1396         size_t offset_, int *found_bracket)
1397 {
1398         size_t equal_offset = size, bracket_offset = size;
1399         ssize_t offset;
1400
1401 contline:
1402         for (offset = offset_-2; offset > 0
1403                         && contents[offset] != '\n'; offset--)
1404                 switch (contents[offset]) {
1405                         case '=': equal_offset = offset; break;
1406                         case ']': bracket_offset = offset; break;
1407                 }
1408         if (offset > 0 && contents[offset-1] == '\\') {
1409                 offset_ = offset;
1410                 goto contline;
1411         }
1412         if (bracket_offset < equal_offset) {
1413                 *found_bracket = 1;
1414                 offset = bracket_offset+1;
1415         } else
1416                 offset++;
1417
1418         return offset;
1419 }
1420
1421 int git_config_set_in_file(const char *config_filename,
1422                         const char *key, const char *value)
1423 {
1424         return git_config_set_multivar_in_file(config_filename, key, value, NULL, 0);
1425 }
1426
1427 int git_config_set(const char *key, const char *value)
1428 {
1429         return git_config_set_multivar(key, value, NULL, 0);
1430 }
1431
1432 /*
1433  * Auxiliary function to sanity-check and split the key into the section
1434  * identifier and variable name.
1435  *
1436  * Returns 0 on success, -1 when there is an invalid character in the key and
1437  * -2 if there is no section name in the key.
1438  *
1439  * store_key - pointer to char* which will hold a copy of the key with
1440  *             lowercase section and variable name
1441  * baselen - pointer to int which will hold the length of the
1442  *           section + subsection part, can be NULL
1443  */
1444 int git_config_parse_key(const char *key, char **store_key, int *baselen_)
1445 {
1446         int i, dot, baselen;
1447         const char *last_dot = strrchr(key, '.');
1448
1449         /*
1450          * Since "key" actually contains the section name and the real
1451          * key name separated by a dot, we have to know where the dot is.
1452          */
1453
1454         if (last_dot == NULL || last_dot == key) {
1455                 error("key does not contain a section: %s", key);
1456                 return -CONFIG_NO_SECTION_OR_NAME;
1457         }
1458
1459         if (!last_dot[1]) {
1460                 error("key does not contain variable name: %s", key);
1461                 return -CONFIG_NO_SECTION_OR_NAME;
1462         }
1463
1464         baselen = last_dot - key;
1465         if (baselen_)
1466                 *baselen_ = baselen;
1467
1468         /*
1469          * Validate the key and while at it, lower case it for matching.
1470          */
1471         *store_key = xmalloc(strlen(key) + 1);
1472
1473         dot = 0;
1474         for (i = 0; key[i]; i++) {
1475                 unsigned char c = key[i];
1476                 if (c == '.')
1477                         dot = 1;
1478                 /* Leave the extended basename untouched.. */
1479                 if (!dot || i > baselen) {
1480                         if (!iskeychar(c) ||
1481                             (i == baselen + 1 && !isalpha(c))) {
1482                                 error("invalid key: %s", key);
1483                                 goto out_free_ret_1;
1484                         }
1485                         c = tolower(c);
1486                 } else if (c == '\n') {
1487                         error("invalid key (newline): %s", key);
1488                         goto out_free_ret_1;
1489                 }
1490                 (*store_key)[i] = c;
1491         }
1492         (*store_key)[i] = 0;
1493
1494         return 0;
1495
1496 out_free_ret_1:
1497         free(*store_key);
1498         *store_key = NULL;
1499         return -CONFIG_INVALID_KEY;
1500 }
1501
1502 /*
1503  * If value==NULL, unset in (remove from) config,
1504  * if value_regex!=NULL, disregard key/value pairs where value does not match.
1505  * if multi_replace==0, nothing, or only one matching key/value is replaced,
1506  *     else all matching key/values (regardless how many) are removed,
1507  *     before the new pair is written.
1508  *
1509  * Returns 0 on success.
1510  *
1511  * This function does this:
1512  *
1513  * - it locks the config file by creating ".git/config.lock"
1514  *
1515  * - it then parses the config using store_aux() as validator to find
1516  *   the position on the key/value pair to replace. If it is to be unset,
1517  *   it must be found exactly once.
1518  *
1519  * - the config file is mmap()ed and the part before the match (if any) is
1520  *   written to the lock file, then the changed part and the rest.
1521  *
1522  * - the config file is removed and the lock file rename()d to it.
1523  *
1524  */
1525 int git_config_set_multivar_in_file(const char *config_filename,
1526                                 const char *key, const char *value,
1527                                 const char *value_regex, int multi_replace)
1528 {
1529         int fd = -1, in_fd;
1530         int ret;
1531         struct lock_file *lock = NULL;
1532         char *filename_buf = NULL;
1533
1534         /* parse-key returns negative; flip the sign to feed exit(3) */
1535         ret = 0 - git_config_parse_key(key, &store.key, &store.baselen);
1536         if (ret)
1537                 goto out_free;
1538
1539         store.multi_replace = multi_replace;
1540
1541         if (!config_filename)
1542                 config_filename = filename_buf = git_pathdup("config");
1543
1544         /*
1545          * The lock serves a purpose in addition to locking: the new
1546          * contents of .git/config will be written into it.
1547          */
1548         lock = xcalloc(sizeof(struct lock_file), 1);
1549         fd = hold_lock_file_for_update(lock, config_filename, 0);
1550         if (fd < 0) {
1551                 error("could not lock config file %s: %s", config_filename, strerror(errno));
1552                 free(store.key);
1553                 ret = CONFIG_NO_LOCK;
1554                 goto out_free;
1555         }
1556
1557         /*
1558          * If .git/config does not exist yet, write a minimal version.
1559          */
1560         in_fd = open(config_filename, O_RDONLY);
1561         if ( in_fd < 0 ) {
1562                 free(store.key);
1563
1564                 if ( ENOENT != errno ) {
1565                         error("opening %s: %s", config_filename,
1566                               strerror(errno));
1567                         ret = CONFIG_INVALID_FILE; /* same as "invalid config file" */
1568                         goto out_free;
1569                 }
1570                 /* if nothing to unset, error out */
1571                 if (value == NULL) {
1572                         ret = CONFIG_NOTHING_SET;
1573                         goto out_free;
1574                 }
1575
1576                 store.key = (char *)key;
1577                 if (!store_write_section(fd, key) ||
1578                     !store_write_pair(fd, key, value))
1579                         goto write_err_out;
1580         } else {
1581                 struct stat st;
1582                 char *contents;
1583                 size_t contents_sz, copy_begin, copy_end;
1584                 int i, new_line = 0;
1585
1586                 if (value_regex == NULL)
1587                         store.value_regex = NULL;
1588                 else {
1589                         if (value_regex[0] == '!') {
1590                                 store.do_not_match = 1;
1591                                 value_regex++;
1592                         } else
1593                                 store.do_not_match = 0;
1594
1595                         store.value_regex = (regex_t*)xmalloc(sizeof(regex_t));
1596                         if (regcomp(store.value_regex, value_regex,
1597                                         REG_EXTENDED)) {
1598                                 error("invalid pattern: %s", value_regex);
1599                                 free(store.value_regex);
1600                                 ret = CONFIG_INVALID_PATTERN;
1601                                 goto out_free;
1602                         }
1603                 }
1604
1605                 ALLOC_GROW(store.offset, 1, store.offset_alloc);
1606                 store.offset[0] = 0;
1607                 store.state = START;
1608                 store.seen = 0;
1609
1610                 /*
1611                  * After this, store.offset will contain the *end* offset
1612                  * of the last match, or remain at 0 if no match was found.
1613                  * As a side effect, we make sure to transform only a valid
1614                  * existing config file.
1615                  */
1616                 if (git_config_from_file(store_aux, config_filename, NULL)) {
1617                         error("invalid config file %s", config_filename);
1618                         free(store.key);
1619                         if (store.value_regex != NULL) {
1620                                 regfree(store.value_regex);
1621                                 free(store.value_regex);
1622                         }
1623                         ret = CONFIG_INVALID_FILE;
1624                         goto out_free;
1625                 }
1626
1627                 free(store.key);
1628                 if (store.value_regex != NULL) {
1629                         regfree(store.value_regex);
1630                         free(store.value_regex);
1631                 }
1632
1633                 /* if nothing to unset, or too many matches, error out */
1634                 if ((store.seen == 0 && value == NULL) ||
1635                                 (store.seen > 1 && multi_replace == 0)) {
1636                         ret = CONFIG_NOTHING_SET;
1637                         goto out_free;
1638                 }
1639
1640                 fstat(in_fd, &st);
1641                 contents_sz = xsize_t(st.st_size);
1642                 contents = xmmap(NULL, contents_sz, PROT_READ,
1643                         MAP_PRIVATE, in_fd, 0);
1644                 close(in_fd);
1645
1646                 if (store.seen == 0)
1647                         store.seen = 1;
1648
1649                 for (i = 0, copy_begin = 0; i < store.seen; i++) {
1650                         if (store.offset[i] == 0) {
1651                                 store.offset[i] = copy_end = contents_sz;
1652                         } else if (store.state != KEY_SEEN) {
1653                                 copy_end = store.offset[i];
1654                         } else
1655                                 copy_end = find_beginning_of_line(
1656                                         contents, contents_sz,
1657                                         store.offset[i]-2, &new_line);
1658
1659                         if (copy_end > 0 && contents[copy_end-1] != '\n')
1660                                 new_line = 1;
1661
1662                         /* write the first part of the config */
1663                         if (copy_end > copy_begin) {
1664                                 if (write_in_full(fd, contents + copy_begin,
1665                                                   copy_end - copy_begin) <
1666                                     copy_end - copy_begin)
1667                                         goto write_err_out;
1668                                 if (new_line &&
1669                                     write_str_in_full(fd, "\n") != 1)
1670                                         goto write_err_out;
1671                         }
1672                         copy_begin = store.offset[i];
1673                 }
1674
1675                 /* write the pair (value == NULL means unset) */
1676                 if (value != NULL) {
1677                         if (store.state == START) {
1678                                 if (!store_write_section(fd, key))
1679                                         goto write_err_out;
1680                         }
1681                         if (!store_write_pair(fd, key, value))
1682                                 goto write_err_out;
1683                 }
1684
1685                 /* write the rest of the config */
1686                 if (copy_begin < contents_sz)
1687                         if (write_in_full(fd, contents + copy_begin,
1688                                           contents_sz - copy_begin) <
1689                             contents_sz - copy_begin)
1690                                 goto write_err_out;
1691
1692                 munmap(contents, contents_sz);
1693         }
1694
1695         if (commit_lock_file(lock) < 0) {
1696                 error("could not commit config file %s", config_filename);
1697                 ret = CONFIG_NO_WRITE;
1698                 goto out_free;
1699         }
1700
1701         /*
1702          * lock is committed, so don't try to roll it back below.
1703          * NOTE: Since lockfile.c keeps a linked list of all created
1704          * lock_file structures, it isn't safe to free(lock).  It's
1705          * better to just leave it hanging around.
1706          */
1707         lock = NULL;
1708         ret = 0;
1709
1710 out_free:
1711         if (lock)
1712                 rollback_lock_file(lock);
1713         free(filename_buf);
1714         return ret;
1715
1716 write_err_out:
1717         ret = write_error(lock->filename);
1718         goto out_free;
1719
1720 }
1721
1722 int git_config_set_multivar(const char *key, const char *value,
1723                         const char *value_regex, int multi_replace)
1724 {
1725         return git_config_set_multivar_in_file(NULL, key, value, value_regex,
1726                                                multi_replace);
1727 }
1728
1729 static int section_name_match (const char *buf, const char *name)
1730 {
1731         int i = 0, j = 0, dot = 0;
1732         if (buf[i] != '[')
1733                 return 0;
1734         for (i = 1; buf[i] && buf[i] != ']'; i++) {
1735                 if (!dot && isspace(buf[i])) {
1736                         dot = 1;
1737                         if (name[j++] != '.')
1738                                 break;
1739                         for (i++; isspace(buf[i]); i++)
1740                                 ; /* do nothing */
1741                         if (buf[i] != '"')
1742                                 break;
1743                         continue;
1744                 }
1745                 if (buf[i] == '\\' && dot)
1746                         i++;
1747                 else if (buf[i] == '"' && dot) {
1748                         for (i++; isspace(buf[i]); i++)
1749                                 ; /* do_nothing */
1750                         break;
1751                 }
1752                 if (buf[i] != name[j++])
1753                         break;
1754         }
1755         if (buf[i] == ']' && name[j] == 0) {
1756                 /*
1757                  * We match, now just find the right length offset by
1758                  * gobbling up any whitespace after it, as well
1759                  */
1760                 i++;
1761                 for (; buf[i] && isspace(buf[i]); i++)
1762                         ; /* do nothing */
1763                 return i;
1764         }
1765         return 0;
1766 }
1767
1768 static int section_name_is_ok(const char *name)
1769 {
1770         /* Empty section names are bogus. */
1771         if (!*name)
1772                 return 0;
1773
1774         /*
1775          * Before a dot, we must be alphanumeric or dash. After the first dot,
1776          * anything goes, so we can stop checking.
1777          */
1778         for (; *name && *name != '.'; name++)
1779                 if (*name != '-' && !isalnum(*name))
1780                         return 0;
1781         return 1;
1782 }
1783
1784 /* if new_name == NULL, the section is removed instead */
1785 int git_config_rename_section_in_file(const char *config_filename,
1786                                       const char *old_name, const char *new_name)
1787 {
1788         int ret = 0, remove = 0;
1789         char *filename_buf = NULL;
1790         struct lock_file *lock;
1791         int out_fd;
1792         char buf[1024];
1793         FILE *config_file;
1794
1795         if (new_name && !section_name_is_ok(new_name)) {
1796                 ret = error("invalid section name: %s", new_name);
1797                 goto out;
1798         }
1799
1800         if (!config_filename)
1801                 config_filename = filename_buf = git_pathdup("config");
1802
1803         lock = xcalloc(sizeof(struct lock_file), 1);
1804         out_fd = hold_lock_file_for_update(lock, config_filename, 0);
1805         if (out_fd < 0) {
1806                 ret = error("could not lock config file %s", config_filename);
1807                 goto out;
1808         }
1809
1810         if (!(config_file = fopen(config_filename, "rb"))) {
1811                 /* no config file means nothing to rename, no error */
1812                 goto unlock_and_out;
1813         }
1814
1815         while (fgets(buf, sizeof(buf), config_file)) {
1816                 int i;
1817                 int length;
1818                 char *output = buf;
1819                 for (i = 0; buf[i] && isspace(buf[i]); i++)
1820                         ; /* do nothing */
1821                 if (buf[i] == '[') {
1822                         /* it's a section */
1823                         int offset = section_name_match(&buf[i], old_name);
1824                         if (offset > 0) {
1825                                 ret++;
1826                                 if (new_name == NULL) {
1827                                         remove = 1;
1828                                         continue;
1829                                 }
1830                                 store.baselen = strlen(new_name);
1831                                 if (!store_write_section(out_fd, new_name)) {
1832                                         ret = write_error(lock->filename);
1833                                         goto out;
1834                                 }
1835                                 /*
1836                                  * We wrote out the new section, with
1837                                  * a newline, now skip the old
1838                                  * section's length
1839                                  */
1840                                 output += offset + i;
1841                                 if (strlen(output) > 0) {
1842                                         /*
1843                                          * More content means there's
1844                                          * a declaration to put on the
1845                                          * next line; indent with a
1846                                          * tab
1847                                          */
1848                                         output -= 1;
1849                                         output[0] = '\t';
1850                                 }
1851                         }
1852                         remove = 0;
1853                 }
1854                 if (remove)
1855                         continue;
1856                 length = strlen(output);
1857                 if (write_in_full(out_fd, output, length) != length) {
1858                         ret = write_error(lock->filename);
1859                         goto out;
1860                 }
1861         }
1862         fclose(config_file);
1863 unlock_and_out:
1864         if (commit_lock_file(lock) < 0)
1865                 ret = error("could not commit config file %s", config_filename);
1866 out:
1867         free(filename_buf);
1868         return ret;
1869 }
1870
1871 int git_config_rename_section(const char *old_name, const char *new_name)
1872 {
1873         return git_config_rename_section_in_file(NULL, old_name, new_name);
1874 }
1875
1876 /*
1877  * Call this to report error for your variable that should not
1878  * get a boolean value (i.e. "[my] var" means "true").
1879  */
1880 #undef config_error_nonbool
1881 int config_error_nonbool(const char *var)
1882 {
1883         return error("Missing value for '%s'", var);
1884 }
1885
1886 int parse_config_key(const char *var,
1887                      const char *section,
1888                      const char **subsection, int *subsection_len,
1889                      const char **key)
1890 {
1891         int section_len = strlen(section);
1892         const char *dot;
1893
1894         /* Does it start with "section." ? */
1895         if (!starts_with(var, section) || var[section_len] != '.')
1896                 return -1;
1897
1898         /*
1899          * Find the key; we don't know yet if we have a subsection, but we must
1900          * parse backwards from the end, since the subsection may have dots in
1901          * it, too.
1902          */
1903         dot = strrchr(var, '.');
1904         *key = dot + 1;
1905
1906         /* Did we have a subsection at all? */
1907         if (dot == var + section_len) {
1908                 *subsection = NULL;
1909                 *subsection_len = 0;
1910         }
1911         else {
1912                 *subsection = var + section_len + 1;
1913                 *subsection_len = dot - *subsection;
1914         }
1915
1916         return 0;
1917 }