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         if (!skip_prefix(var, "include.", &type))
 142                 return ret;
 143
 144         if (!strcmp(type, "path"))
 145                 ret = handle_path_include(value, inc);
 146         return ret;
 147 }
 148
 149 void git_config_push_parameter(const char *text)
 150 {
 151         struct strbuf env = STRBUF_INIT;
 152         const char *old = getenv(CONFIG_DATA_ENVIRONMENT);
 153         if (old) {
 154                 strbuf_addstr(&env, old);
 155                 strbuf_addch(&env, ' ');
 156         }
 157         sq_quote_buf(&env, text);
 158         setenv(CONFIG_DATA_ENVIRONMENT, env.buf, 1);
 159         strbuf_release(&env);
 160 }
 161
 162 int git_config_parse_parameter(const char *text,
 163                                config_fn_t fn, void *data)
 164 {
 165         struct strbuf **pair;
 166         pair = strbuf_split_str(text, '=', 2);
 167         if (!pair[0])
 168                 return error("bogus config parameter: %s", text);
 169         if (pair[0]->len && pair[0]->buf[pair[0]->len - 1] == '=')
 170                 strbuf_setlen(pair[0], pair[0]->len - 1);
 171         strbuf_trim(pair[0]);
 172         if (!pair[0]->len) {
 173                 strbuf_list_free(pair);
 174                 return error("bogus config parameter: %s", text);
 175         }
 176         strbuf_tolower(pair[0]);
 177         if (fn(pair[0]->buf, pair[1] ? pair[1]->buf : NULL, data) < 0) {
 178                 strbuf_list_free(pair);
 179                 return -1;
 180         }
 181         strbuf_list_free(pair);
 182         return 0;
 183 }
 184
 185 int git_config_from_parameters(config_fn_t fn, void *data)
 186 {
 187         const char *env = getenv(CONFIG_DATA_ENVIRONMENT);
 188         char *envw;
 189         const char **argv = NULL;
 190         int nr = 0, alloc = 0;
 191         int i;
 192
 193         if (!env)
 194                 return 0;
 195         /* sq_dequote will write over it */
 196         envw = xstrdup(env);
 197
 198         if (sq_dequote_to_argv(envw, &argv, &nr, &alloc) < 0) {
 199                 free(envw);
 200                 return error("bogus format in " CONFIG_DATA_ENVIRONMENT);
 201         }
 202
 203         for (i = 0; i < nr; i++) {
 204                 if (git_config_parse_parameter(argv[i], fn, data) < 0) {
 205                         free(argv);
 206                         free(envw);
 207                         return -1;
 208                 }
 209         }
 210
 211         free(argv);
 212         free(envw);
 213         return nr > 0;
 214 }
 215
 216 static int get_next_char(void)
 217 {
 218         int c = cf->do_fgetc(cf);
 219
 220         if (c == '\r') {
 221                 /* DOS like systems */
 222                 c = cf->do_fgetc(cf);
 223                 if (c != '\n') {
 224                         cf->do_ungetc(c, cf);
 225                         c = '\r';
 226                 }
 227         }
 228         if (c == '\n')
 229                 cf->linenr++;
 230         if (c == EOF) {
 231                 cf->eof = 1;
 232                 c = '\n';
 233         }
 234         return c;
 235 }
 236
 237 static char *parse_value(void)
 238 {
 239         int quote = 0, comment = 0, space = 0;
 240
 241         strbuf_reset(&cf->value);
 242         for (;;) {
 243                 int c = get_next_char();
 244                 if (c == '\n') {
 245                         if (quote) {
 246                                 cf->linenr--;
 247                                 return NULL;
 248                         }
 249                         return cf->value.buf;
 250                 }
 251                 if (comment)
 252                         continue;
 253                 if (isspace(c) && !quote) {
 254                         if (cf->value.len)
 255                                 space++;
 256                         continue;
 257                 }
 258                 if (!quote) {
 259                         if (c == ';' || c == '#') {
 260                                 comment = 1;
 261                                 continue;
 262                         }
 263                 }
 264                 for (; space; space--)
 265                         strbuf_addch(&cf->value, ' ');
 266                 if (c == '\\') {
 267                         c = get_next_char();
 268                         switch (c) {
 269                         case '\n':
 270                                 continue;
 271                         case 't':
 272                                 c = '\t';
 273                                 break;
 274                         case 'b':
 275                                 c = '\b';
 276                                 break;
 277                         case 'n':
 278                                 c = '\n';
 279                                 break;
 280                         /* Some characters escape as themselves */
 281                         case '\\': case '"':
 282                                 break;
 283                         /* Reject unknown escape sequences */
 284                         default:
 285                                 return NULL;
 286                         }
 287                         strbuf_addch(&cf->value, c);
 288                         continue;
 289                 }
 290                 if (c == '"') {
 291                         quote = 1-quote;
 292                         continue;
 293                 }
 294                 strbuf_addch(&cf->value, c);
 295         }
 296 }
 297
 298 static inline int iskeychar(int c)
 299 {
 300         return isalnum(c) || c == '-';
 301 }
 302
 303 static int get_value(config_fn_t fn, void *data, struct strbuf *name)
 304 {
 305         int c;
 306         char *value;
 307
 308         /* Get the full name */
 309         for (;;) {
 310                 c = get_next_char();
 311                 if (cf->eof)
 312                         break;
 313                 if (!iskeychar(c))
 314                         break;
 315                 strbuf_addch(name, tolower(c));
 316         }
 317
 318         while (c == ' ' || c == '\t')
 319                 c = get_next_char();
 320
 321         value = NULL;
 322         if (c != '\n') {
 323                 if (c != '=')
 324                         return -1;
 325                 value = parse_value();
 326                 if (!value)
 327                         return -1;
 328         }
 329         return fn(name->buf, value, data);
 330 }
 331
 332 static int get_extended_base_var(struct strbuf *name, int c)
 333 {
 334         do {
 335                 if (c == '\n')
 336                         goto error_incomplete_line;
 337                 c = get_next_char();
 338         } while (isspace(c));
 339
 340         /* We require the format to be '[base "extension"]' */
 341         if (c != '"')
 342                 return -1;
 343         strbuf_addch(name, '.');
 344
 345         for (;;) {
 346                 int c = get_next_char();
 347                 if (c == '\n')
 348                         goto error_incomplete_line;
 349                 if (c == '"')
 350                         break;
 351                 if (c == '\\') {
 352                         c = get_next_char();
 353                         if (c == '\n')
 354                                 goto error_incomplete_line;
 355                 }
 356                 strbuf_addch(name, c);
 357         }
 358
 359         /* Final ']' */
 360         if (get_next_char() != ']')
 361                 return -1;
 362         return 0;
 363 error_incomplete_line:
 364         cf->linenr--;
 365         return -1;
 366 }
 367
 368 static int get_base_var(struct strbuf *name)
 369 {
 370         for (;;) {
 371                 int c = get_next_char();
 372                 if (cf->eof)
 373                         return -1;
 374                 if (c == ']')
 375                         return 0;
 376                 if (isspace(c))
 377                         return get_extended_base_var(name, c);
 378                 if (!iskeychar(c) && c != '.')
 379                         return -1;
 380                 strbuf_addch(name, tolower(c));
 381         }
 382 }
 383
 384 static int git_parse_source(config_fn_t fn, void *data)
 385 {
 386         int comment = 0;
 387         int baselen = 0;
 388         struct strbuf *var = &cf->var;
 389
 390         /* U+FEFF Byte Order Mark in UTF8 */
 391         static const unsigned char *utf8_bom = (unsigned char *) "\xef\xbb\xbf";
 392         const unsigned char *bomptr = utf8_bom;
 393
 394         for (;;) {
 395                 int c = get_next_char();
 396                 if (bomptr && *bomptr) {
 397                         /* We are at the file beginning; skip UTF8-encoded BOM
 398                          * if present. Sane editors won't put this in on their
 399                          * own, but e.g. Windows Notepad will do it happily. */
 400                         if ((unsigned char) c == *bomptr) {
 401                                 bomptr++;
 402                                 continue;
 403                         } else {
 404                                 /* Do not tolerate partial BOM. */
 405                                 if (bomptr != utf8_bom)
 406                                         break;
 407                                 /* No BOM at file beginning. Cool. */
 408                                 bomptr = NULL;
 409                         }
 410                 }
 411                 if (c == '\n') {
 412                         if (cf->eof)
 413                                 return 0;
 414                         comment = 0;
 415                         continue;
 416                 }
 417                 if (comment || isspace(c))
 418                         continue;
 419                 if (c == '#' || c == ';') {
 420                         comment = 1;
 421                         continue;
 422                 }
 423                 if (c == '[') {
 424                         /* Reset prior to determining a new stem */
 425                         strbuf_reset(var);
 426                         if (get_base_var(var) < 0 || var->len < 1)
 427                                 break;
 428                         strbuf_addch(var, '.');
 429                         baselen = var->len;
 430                         continue;
 431                 }
 432                 if (!isalpha(c))
 433                         break;
 434                 /*
 435                  * Truncate the var name back to the section header
 436                  * stem prior to grabbing the suffix part of the name
 437                  * and the value.
 438                  */
 439                 strbuf_setlen(var, baselen);
 440                 strbuf_addch(var, tolower(c));
 441                 if (get_value(fn, data, var) < 0)
 442                         break;
 443         }
 444         if (cf->die_on_error)
 445                 die("bad config file line %d in %s", cf->linenr, cf->name);
 446         else
 447                 return error("bad config file line %d in %s", cf->linenr, cf->name);
 448 }
 449
 450 static int parse_unit_factor(const char *end, uintmax_t *val)
 451 {
 452         if (!*end)
 453                 return 1;
 454         else if (!strcasecmp(end, "k")) {
 455                 *val *= 1024;
 456                 return 1;
 457         }
 458         else if (!strcasecmp(end, "m")) {
 459                 *val *= 1024 * 1024;
 460                 return 1;
 461         }
 462         else if (!strcasecmp(end, "g")) {
 463                 *val *= 1024 * 1024 * 1024;
 464                 return 1;
 465         }
 466         return 0;
 467 }
 468
 469 static int git_parse_signed(const char *value, intmax_t *ret, intmax_t max)
 470 {
 471         if (value && *value) {
 472                 char *end;
 473                 intmax_t val;
 474                 uintmax_t uval;
 475                 uintmax_t factor = 1;
 476
 477                 errno = 0;
 478                 val = strtoimax(value, &end, 0);
 479                 if (errno == ERANGE)
 480                         return 0;
 481                 if (!parse_unit_factor(end, &factor)) {
 482                         errno = EINVAL;
 483                         return 0;
 484                 }
 485                 uval = abs(val);
 486                 uval *= factor;
 487                 if (uval > max || abs(val) > uval) {
 488                         errno = ERANGE;
 489                         return 0;
 490                 }
 491                 val *= factor;
 492                 *ret = val;
 493                 return 1;
 494         }
 495         errno = EINVAL;
 496         return 0;
 497 }
 498
 499 static int git_parse_unsigned(const char *value, uintmax_t *ret, uintmax_t max)
 500 {
 501         if (value && *value) {
 502                 char *end;
 503                 uintmax_t val;
 504                 uintmax_t oldval;
 505
 506                 errno = 0;
 507                 val = strtoumax(value, &end, 0);
 508                 if (errno == ERANGE)
 509                         return 0;
 510                 oldval = val;
 511                 if (!parse_unit_factor(end, &val)) {
 512                         errno = EINVAL;
 513                         return 0;
 514                 }
 515                 if (val > max || oldval > val) {
 516                         errno = ERANGE;
 517                         return 0;
 518                 }
 519                 *ret = val;
 520                 return 1;
 521         }
 522         errno = EINVAL;
 523         return 0;
 524 }
 525
 526 static int git_parse_int(const char *value, int *ret)
 527 {
 528         intmax_t tmp;
 529         if (!git_parse_signed(value, &tmp, maximum_signed_value_of_type(int)))
 530                 return 0;
 531         *ret = tmp;
 532         return 1;
 533 }
 534
 535 static int git_parse_int64(const char *value, int64_t *ret)
 536 {
 537         intmax_t tmp;
 538         if (!git_parse_signed(value, &tmp, maximum_signed_value_of_type(int64_t)))
 539                 return 0;
 540         *ret = tmp;
 541         return 1;
 542 }
 543
 544 int git_parse_ulong(const char *value, unsigned long *ret)
 545 {
 546         uintmax_t tmp;
 547         if (!git_parse_unsigned(value, &tmp, maximum_unsigned_value_of_type(long)))
 548                 return 0;
 549         *ret = tmp;
 550         return 1;
 551 }
 552
 553 NORETURN
 554 static void die_bad_number(const char *name, const char *value)
 555 {
 556         const char *reason = errno == ERANGE ?
 557                              "out of range" :
 558                              "invalid unit";
 559         if (!value)
 560                 value = "";
 561
 562         if (cf && cf->name)
 563                 die("bad numeric config value '%s' for '%s' in %s: %s",
 564                     value, name, cf->name, reason);
 565         die("bad numeric config value '%s' for '%s': %s", value, name, reason);
 566 }
 567
 568 int git_config_int(const char *name, const char *value)
 569 {
 570         int ret;
 571         if (!git_parse_int(value, &ret))
 572                 die_bad_number(name, value);
 573         return ret;
 574 }
 575
 576 int64_t git_config_int64(const char *name, const char *value)
 577 {
 578         int64_t ret;
 579         if (!git_parse_int64(value, &ret))
 580                 die_bad_number(name, value);
 581         return ret;
 582 }
 583
 584 unsigned long git_config_ulong(const char *name, const char *value)
 585 {
 586         unsigned long ret;
 587         if (!git_parse_ulong(value, &ret))
 588                 die_bad_number(name, value);
 589         return ret;
 590 }
 591
 592 static int git_config_maybe_bool_text(const char *name, const char *value)
 593 {
 594         if (!value)
 595                 return 1;
 596         if (!*value)
 597                 return 0;
 598         if (!strcasecmp(value, "true")
 599             || !strcasecmp(value, "yes")
 600             || !strcasecmp(value, "on"))
 601                 return 1;
 602         if (!strcasecmp(value, "false")
 603             || !strcasecmp(value, "no")
 604             || !strcasecmp(value, "off"))
 605                 return 0;
 606         return -1;
 607 }
 608
 609 int git_config_maybe_bool(const char *name, const char *value)
 610 {
 611         int v = git_config_maybe_bool_text(name, value);
 612         if (0 <= v)
 613                 return v;
 614         if (git_parse_int(value, &v))
 615                 return !!v;
 616         return -1;
 617 }
 618
 619 int git_config_bool_or_int(const char *name, const char *value, int *is_bool)
 620 {
 621         int v = git_config_maybe_bool_text(name, value);
 622         if (0 <= v) {
 623                 *is_bool = 1;
 624                 return v;
 625         }
 626         *is_bool = 0;
 627         return git_config_int(name, value);
 628 }
 629
 630 int git_config_bool(const char *name, const char *value)
 631 {
 632         int discard;
 633         return !!git_config_bool_or_int(name, value, &discard);
 634 }
 635
 636 int git_config_string(const char **dest, const char *var, const char *value)
 637 {
 638         if (!value)
 639                 return config_error_nonbool(var);
 640         *dest = xstrdup(value);
 641         return 0;
 642 }
 643
 644 int git_config_pathname(const char **dest, const char *var, const char *value)
 645 {
 646         if (!value)
 647                 return config_error_nonbool(var);
 648         *dest = expand_user_path(value);
 649         if (!*dest)
 650                 die("Failed to expand user dir in: '%s'", value);
 651         return 0;
 652 }
 653
 654 static int git_default_core_config(const char *var, const char *value)
 655 {
 656         /* This needs a better name */
 657         if (!strcmp(var, "core.filemode")) {
 658                 trust_executable_bit = git_config_bool(var, value);
 659                 return 0;
 660         }
 661         if (!strcmp(var, "core.trustctime")) {
 662                 trust_ctime = git_config_bool(var, value);
 663                 return 0;
 664         }
 665         if (!strcmp(var, "core.checkstat")) {
 666                 if (!strcasecmp(value, "default"))
 667                         check_stat = 1;
 668                 else if (!strcasecmp(value, "minimal"))
 669                         check_stat = 0;
 670         }
 671
 672         if (!strcmp(var, "core.quotepath")) {
 673                 quote_path_fully = git_config_bool(var, value);
 674                 return 0;
 675         }
 676
 677         if (!strcmp(var, "core.symlinks")) {
 678                 has_symlinks = git_config_bool(var, value);
 679                 return 0;
 680         }
 681
 682         if (!strcmp(var, "core.ignorecase")) {
 683                 ignore_case = git_config_bool(var, value);
 684                 return 0;
 685         }
 686
 687         if (!strcmp(var, "core.attributesfile"))
 688                 return git_config_pathname(&git_attributes_file, var, value);
 689
 690         if (!strcmp(var, "core.bare")) {
 691                 is_bare_repository_cfg = git_config_bool(var, value);
 692                 return 0;
 693         }
 694
 695         if (!strcmp(var, "core.ignorestat")) {
 696                 assume_unchanged = git_config_bool(var, value);
 697                 return 0;
 698         }
 699
 700         if (!strcmp(var, "core.prefersymlinkrefs")) {
 701                 prefer_symlink_refs = git_config_bool(var, value);
 702                 return 0;
 703         }
 704
 705         if (!strcmp(var, "core.logallrefupdates")) {
 706                 log_all_ref_updates = git_config_bool(var, value);
 707                 return 0;
 708         }
 709
 710         if (!strcmp(var, "core.warnambiguousrefs")) {
 711                 warn_ambiguous_refs = git_config_bool(var, value);
 712                 return 0;
 713         }
 714
 715         if (!strcmp(var, "core.abbrev")) {
 716                 int abbrev = git_config_int(var, value);
 717                 if (abbrev < minimum_abbrev || abbrev > 40)
 718                         return -1;
 719                 default_abbrev = abbrev;
 720                 return 0;
 721         }
 722
 723         if (!strcmp(var, "core.loosecompression")) {
 724                 int level = git_config_int(var, value);
 725                 if (level == -1)
 726                         level = Z_DEFAULT_COMPRESSION;
 727                 else if (level < 0 || level > Z_BEST_COMPRESSION)
 728                         die("bad zlib compression level %d", level);
 729                 zlib_compression_level = level;
 730                 zlib_compression_seen = 1;
 731                 return 0;
 732         }
 733
 734         if (!strcmp(var, "core.compression")) {
 735                 int level = git_config_int(var, value);
 736                 if (level == -1)
 737                         level = Z_DEFAULT_COMPRESSION;
 738                 else if (level < 0 || level > Z_BEST_COMPRESSION)
 739                         die("bad zlib compression level %d", level);
 740                 core_compression_level = level;
 741                 core_compression_seen = 1;
 742                 if (!zlib_compression_seen)
 743                         zlib_compression_level = level;
 744                 return 0;
 745         }
 746
 747         if (!strcmp(var, "core.packedgitwindowsize")) {
 748                 int pgsz_x2 = getpagesize() * 2;
 749                 packed_git_window_size = git_config_ulong(var, value);
 750
 751                 /* This value must be multiple of (pagesize * 2) */
 752                 packed_git_window_size /= pgsz_x2;
 753                 if (packed_git_window_size < 1)
 754                         packed_git_window_size = 1;
 755                 packed_git_window_size *= pgsz_x2;
 756                 return 0;
 757         }
 758
 759         if (!strcmp(var, "core.bigfilethreshold")) {
 760                 big_file_threshold = git_config_ulong(var, value);
 761                 return 0;
 762         }
 763
 764         if (!strcmp(var, "core.packedgitlimit")) {
 765                 packed_git_limit = git_config_ulong(var, value);
 766                 return 0;
 767         }
 768
 769         if (!strcmp(var, "core.deltabasecachelimit")) {
 770                 delta_base_cache_limit = git_config_ulong(var, value);
 771                 return 0;
 772         }
 773
 774         if (!strcmp(var, "core.autocrlf")) {
 775                 if (value && !strcasecmp(value, "input")) {
 776                         if (core_eol == EOL_CRLF)
 777                                 return error("core.autocrlf=input conflicts with core.eol=crlf");
 778                         auto_crlf = AUTO_CRLF_INPUT;
 779                         return 0;
 780                 }
 781                 auto_crlf = git_config_bool(var, value);
 782                 return 0;
 783         }
 784
 785         if (!strcmp(var, "core.safecrlf")) {
 786                 if (value && !strcasecmp(value, "warn")) {
 787                         safe_crlf = SAFE_CRLF_WARN;
 788                         return 0;
 789                 }
 790                 safe_crlf = git_config_bool(var, value);
 791                 return 0;
 792         }
 793
 794         if (!strcmp(var, "core.eol")) {
 795                 if (value && !strcasecmp(value, "lf"))
 796                         core_eol = EOL_LF;
 797                 else if (value && !strcasecmp(value, "crlf"))
 798                         core_eol = EOL_CRLF;
 799                 else if (value && !strcasecmp(value, "native"))
 800                         core_eol = EOL_NATIVE;
 801                 else
 802                         core_eol = EOL_UNSET;
 803                 if (core_eol == EOL_CRLF && auto_crlf == AUTO_CRLF_INPUT)
 804                         return error("core.autocrlf=input conflicts with core.eol=crlf");
 805                 return 0;
 806         }
 807
 808         if (!strcmp(var, "core.notesref")) {
 809                 notes_ref_name = xstrdup(value);
 810                 return 0;
 811         }
 812
 813         if (!strcmp(var, "core.pager"))
 814                 return git_config_string(&pager_program, var, value);
 815
 816         if (!strcmp(var, "core.editor"))
 817                 return git_config_string(&editor_program, var, value);
 818
 819         if (!strcmp(var, "core.commentchar")) {
 820                 if (!value)
 821                         return config_error_nonbool(var);
 822                 else if (!strcasecmp(value, "auto"))
 823                         auto_comment_line_char = 1;
 824                 else if (value[0] && !value[1]) {
 825                         comment_line_char = value[0];
 826                         auto_comment_line_char = 0;
 827                 } else
 828                         return error("core.commentChar should only be one character");
 829                 return 0;
 830         }
 831
 832         if (!strcmp(var, "core.askpass"))
 833                 return git_config_string(&askpass_program, var, value);
 834
 835         if (!strcmp(var, "core.excludesfile"))
 836                 return git_config_pathname(&excludes_file, var, value);
 837
 838         if (!strcmp(var, "core.whitespace")) {
 839                 if (!value)
 840                         return config_error_nonbool(var);
 841                 whitespace_rule_cfg = parse_whitespace_rule(value);
 842                 return 0;
 843         }
 844
 845         if (!strcmp(var, "core.fsyncobjectfiles")) {
 846                 fsync_object_files = git_config_bool(var, value);
 847                 return 0;
 848         }
 849
 850         if (!strcmp(var, "core.preloadindex")) {
 851                 core_preload_index = git_config_bool(var, value);
 852                 return 0;
 853         }
 854
 855         if (!strcmp(var, "core.createobject")) {
 856                 if (!strcmp(value, "rename"))
 857                         object_creation_mode = OBJECT_CREATION_USES_RENAMES;
 858                 else if (!strcmp(value, "link"))
 859                         object_creation_mode = OBJECT_CREATION_USES_HARDLINKS;
 860                 else
 861                         die("Invalid mode for object creation: %s", value);
 862                 return 0;
 863         }
 864
 865         if (!strcmp(var, "core.sparsecheckout")) {
 866                 core_apply_sparse_checkout = git_config_bool(var, value);
 867                 return 0;
 868         }
 869
 870         if (!strcmp(var, "core.precomposeunicode")) {
 871                 precomposed_unicode = git_config_bool(var, value);
 872                 return 0;
 873         }
 874
 875         /* Add other config variables here and to Documentation/config.txt. */
 876         return 0;
 877 }
 878
 879 static int git_default_i18n_config(const char *var, const char *value)
 880 {
 881         if (!strcmp(var, "i18n.commitencoding"))
 882                 return git_config_string(&git_commit_encoding, var, value);
 883
 884         if (!strcmp(var, "i18n.logoutputencoding"))
 885                 return git_config_string(&git_log_output_encoding, var, value);
 886
 887         /* Add other config variables here and to Documentation/config.txt. */
 888         return 0;
 889 }
 890
 891 static int git_default_branch_config(const char *var, const char *value)
 892 {
 893         if (!strcmp(var, "branch.autosetupmerge")) {
 894                 if (value && !strcasecmp(value, "always")) {
 895                         git_branch_track = BRANCH_TRACK_ALWAYS;
 896                         return 0;
 897                 }
 898                 git_branch_track = git_config_bool(var, value);
 899                 return 0;
 900         }
 901         if (!strcmp(var, "branch.autosetuprebase")) {
 902                 if (!value)
 903                         return config_error_nonbool(var);
 904                 else if (!strcmp(value, "never"))
 905                         autorebase = AUTOREBASE_NEVER;
 906                 else if (!strcmp(value, "local"))
 907                         autorebase = AUTOREBASE_LOCAL;
 908                 else if (!strcmp(value, "remote"))
 909                         autorebase = AUTOREBASE_REMOTE;
 910                 else if (!strcmp(value, "always"))
 911                         autorebase = AUTOREBASE_ALWAYS;
 912                 else
 913                         return error("Malformed value for %s", var);
 914                 return 0;
 915         }
 916
 917         /* Add other config variables here and to Documentation/config.txt. */
 918         return 0;
 919 }
 920
 921 static int git_default_push_config(const char *var, const char *value)
 922 {
 923         if (!strcmp(var, "push.default")) {
 924                 if (!value)
 925                         return config_error_nonbool(var);
 926                 else if (!strcmp(value, "nothing"))
 927                         push_default = PUSH_DEFAULT_NOTHING;
 928                 else if (!strcmp(value, "matching"))
 929                         push_default = PUSH_DEFAULT_MATCHING;
 930                 else if (!strcmp(value, "simple"))
 931                         push_default = PUSH_DEFAULT_SIMPLE;
 932                 else if (!strcmp(value, "upstream"))
 933                         push_default = PUSH_DEFAULT_UPSTREAM;
 934                 else if (!strcmp(value, "tracking")) /* deprecated */
 935                         push_default = PUSH_DEFAULT_UPSTREAM;
 936                 else if (!strcmp(value, "current"))
 937                         push_default = PUSH_DEFAULT_CURRENT;
 938                 else {
 939                         error("Malformed value for %s: %s", var, value);
 940                         return error("Must be one of nothing, matching, simple, "
 941                                      "upstream or current.");
 942                 }
 943                 return 0;
 944         }
 945
 946         /* Add other config variables here and to Documentation/config.txt. */
 947         return 0;
 948 }
 949
 950 static int git_default_mailmap_config(const char *var, const char *value)
 951 {
 952         if (!strcmp(var, "mailmap.file"))
 953                 return git_config_pathname(&git_mailmap_file, var, value);
 954         if (!strcmp(var, "mailmap.blob"))
 955                 return git_config_string(&git_mailmap_blob, var, value);
 956
 957         /* Add other config variables here and to Documentation/config.txt. */
 958         return 0;
 959 }
 960
 961 int git_default_config(const char *var, const char *value, void *dummy)
 962 {
 963         if (starts_with(var, "core."))
 964                 return git_default_core_config(var, value);
 965
 966         if (starts_with(var, "user."))
 967                 return git_ident_config(var, value, dummy);
 968
 969         if (starts_with(var, "i18n."))
 970                 return git_default_i18n_config(var, value);
 971
 972         if (starts_with(var, "branch."))
 973                 return git_default_branch_config(var, value);
 974
 975         if (starts_with(var, "push."))
 976                 return git_default_push_config(var, value);
 977
 978         if (starts_with(var, "mailmap."))
 979                 return git_default_mailmap_config(var, value);
 980
 981         if (starts_with(var, "advice."))
 982                 return git_default_advice_config(var, value);
 983
 984         if (!strcmp(var, "pager.color") || !strcmp(var, "color.pager")) {
 985                 pager_use_color = git_config_bool(var,value);
 986                 return 0;
 987         }
 988
 989         if (!strcmp(var, "pack.packsizelimit")) {
 990                 pack_size_limit_cfg = git_config_ulong(var, value);
 991                 return 0;
 992         }
 993         /* Add other config variables here and to Documentation/config.txt. */
 994         return 0;
 995 }
 996
 997 /*
 998  * All source specific fields in the union, die_on_error, name and the callbacks
 999  * fgetc, ungetc, ftell of top need to be initialized before calling
1000  * this function.
1001  */
1002 static int do_config_from(struct config_source *top, config_fn_t fn, void *data)
1003 {
1004         int ret;
1005
1006         /* push config-file parsing state stack */
1007         top->prev = cf;
1008         top->linenr = 1;
1009         top->eof = 0;
1010         strbuf_init(&top->value, 1024);
1011         strbuf_init(&top->var, 1024);
1012         cf = top;
1013
1014         ret = git_parse_source(fn, data);
1015
1016         /* pop config-file parsing state stack */
1017         strbuf_release(&top->value);
1018         strbuf_release(&top->var);
1019         cf = top->prev;
1020
1021         return ret;
1022 }
1023
1024 static int do_config_from_file(config_fn_t fn,
1025                 const char *name, const char *path, FILE *f, void *data)
1026 {
1027         struct config_source top;
1028
1029         top.u.file = f;
1030         top.name = name;
1031         top.path = path;
1032         top.die_on_error = 1;
1033         top.do_fgetc = config_file_fgetc;
1034         top.do_ungetc = config_file_ungetc;
1035         top.do_ftell = config_file_ftell;
1036
1037         return do_config_from(&top, fn, data);
1038 }
1039
1040 static int git_config_from_stdin(config_fn_t fn, void *data)
1041 {
1042         return do_config_from_file(fn, "<stdin>", NULL, stdin, data);
1043 }
1044
1045 int git_config_from_file(config_fn_t fn, const char *filename, void *data)
1046 {
1047         int ret = -1;
1048         FILE *f;
1049
1050         f = fopen(filename, "r");
1051         if (f) {
1052                 ret = do_config_from_file(fn, filename, filename, f, data);
1053                 fclose(f);
1054         }
1055         return ret;
1056 }
1057
1058 int git_config_from_buf(config_fn_t fn, const char *name, const char *buf,
1059                         size_t len, void *data)
1060 {
1061         struct config_source top;
1062
1063         top.u.buf.buf = buf;
1064         top.u.buf.len = len;
1065         top.u.buf.pos = 0;
1066         top.name = name;
1067         top.path = NULL;
1068         top.die_on_error = 0;
1069         top.do_fgetc = config_buf_fgetc;
1070         top.do_ungetc = config_buf_ungetc;
1071         top.do_ftell = config_buf_ftell;
1072
1073         return do_config_from(&top, fn, data);
1074 }
1075
1076 static int git_config_from_blob_sha1(config_fn_t fn,
1077                                      const char *name,
1078                                      const unsigned char *sha1,
1079                                      void *data)
1080 {
1081         enum object_type type;
1082         char *buf;
1083         unsigned long size;
1084         int ret;
1085
1086         buf = read_sha1_file(sha1, &type, &size);
1087         if (!buf)
1088                 return error("unable to load config blob object '%s'", name);
1089         if (type != OBJ_BLOB) {
1090                 free(buf);
1091                 return error("reference '%s' does not point to a blob", name);
1092         }
1093
1094         ret = git_config_from_buf(fn, name, buf, size, data);
1095         free(buf);
1096
1097         return ret;
1098 }
1099
1100 static int git_config_from_blob_ref(config_fn_t fn,
1101                                     const char *name,
1102                                     void *data)
1103 {
1104         unsigned char sha1[20];
1105
1106         if (get_sha1(name, sha1) < 0)
1107                 return error("unable to resolve config blob '%s'", name);
1108         return git_config_from_blob_sha1(fn, name, sha1, data);
1109 }
1110
1111 const char *git_etc_gitconfig(void)
1112 {
1113         static const char *system_wide;
1114         if (!system_wide)
1115                 system_wide = system_path(ETC_GITCONFIG);
1116         return system_wide;
1117 }
1118
1119 /*
1120  * Parse environment variable 'k' as a boolean (in various
1121  * possible spellings); if missing, use the default value 'def'.
1122  */
1123 int git_env_bool(const char *k, int def)
1124 {
1125         const char *v = getenv(k);
1126         return v ? git_config_bool(k, v) : def;
1127 }
1128
1129 /*
1130  * Parse environment variable 'k' as ulong with possibly a unit
1131  * suffix; if missing, use the default value 'val'.
1132  */
1133 unsigned long git_env_ulong(const char *k, unsigned long val)
1134 {
1135         const char *v = getenv(k);
1136         if (v && !git_parse_ulong(v, &val))
1137                 die("failed to parse %s", k);
1138         return val;
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(1, sizeof(struct lock_file));
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 (chmod(lock->filename, st.st_mode & 07777) < 0) {
1654                         error("chmod on %s failed: %s",
1655                                 lock->filename, strerror(errno));
1656                         ret = CONFIG_NO_WRITE;
1657                         goto out_free;
1658                 }
1659
1660                 if (store.seen == 0)
1661                         store.seen = 1;
1662
1663                 for (i = 0, copy_begin = 0; i < store.seen; i++) {
1664                         if (store.offset[i] == 0) {
1665                                 store.offset[i] = copy_end = contents_sz;
1666                         } else if (store.state != KEY_SEEN) {
1667                                 copy_end = store.offset[i];
1668                         } else
1669                                 copy_end = find_beginning_of_line(
1670                                         contents, contents_sz,
1671                                         store.offset[i]-2, &new_line);
1672
1673                         if (copy_end > 0 && contents[copy_end-1] != '\n')
1674                                 new_line = 1;
1675
1676                         /* write the first part of the config */
1677                         if (copy_end > copy_begin) {
1678                                 if (write_in_full(fd, contents + copy_begin,
1679                                                   copy_end - copy_begin) <
1680                                     copy_end - copy_begin)
1681                                         goto write_err_out;
1682                                 if (new_line &&
1683                                     write_str_in_full(fd, "\n") != 1)
1684                                         goto write_err_out;
1685                         }
1686                         copy_begin = store.offset[i];
1687                 }
1688
1689                 /* write the pair (value == NULL means unset) */
1690                 if (value != NULL) {
1691                         if (store.state == START) {
1692                                 if (!store_write_section(fd, key))
1693                                         goto write_err_out;
1694                         }
1695                         if (!store_write_pair(fd, key, value))
1696                                 goto write_err_out;
1697                 }
1698
1699                 /* write the rest of the config */
1700                 if (copy_begin < contents_sz)
1701                         if (write_in_full(fd, contents + copy_begin,
1702                                           contents_sz - copy_begin) <
1703                             contents_sz - copy_begin)
1704                                 goto write_err_out;
1705
1706                 munmap(contents, contents_sz);
1707         }
1708
1709         if (commit_lock_file(lock) < 0) {
1710                 error("could not commit config file %s", config_filename);
1711                 ret = CONFIG_NO_WRITE;
1712                 goto out_free;
1713         }
1714
1715         /*
1716          * lock is committed, so don't try to roll it back below.
1717          * NOTE: Since lockfile.c keeps a linked list of all created
1718          * lock_file structures, it isn't safe to free(lock).  It's
1719          * better to just leave it hanging around.
1720          */
1721         lock = NULL;
1722         ret = 0;
1723
1724 out_free:
1725         if (lock)
1726                 rollback_lock_file(lock);
1727         free(filename_buf);
1728         return ret;
1729
1730 write_err_out:
1731         ret = write_error(lock->filename);
1732         goto out_free;
1733
1734 }
1735
1736 int git_config_set_multivar(const char *key, const char *value,
1737                         const char *value_regex, int multi_replace)
1738 {
1739         return git_config_set_multivar_in_file(NULL, key, value, value_regex,
1740                                                multi_replace);
1741 }
1742
1743 static int section_name_match (const char *buf, const char *name)
1744 {
1745         int i = 0, j = 0, dot = 0;
1746         if (buf[i] != '[')
1747                 return 0;
1748         for (i = 1; buf[i] && buf[i] != ']'; i++) {
1749                 if (!dot && isspace(buf[i])) {
1750                         dot = 1;
1751                         if (name[j++] != '.')
1752                                 break;
1753                         for (i++; isspace(buf[i]); i++)
1754                                 ; /* do nothing */
1755                         if (buf[i] != '"')
1756                                 break;
1757                         continue;
1758                 }
1759                 if (buf[i] == '\\' && dot)
1760                         i++;
1761                 else if (buf[i] == '"' && dot) {
1762                         for (i++; isspace(buf[i]); i++)
1763                                 ; /* do_nothing */
1764                         break;
1765                 }
1766                 if (buf[i] != name[j++])
1767                         break;
1768         }
1769         if (buf[i] == ']' && name[j] == 0) {
1770                 /*
1771                  * We match, now just find the right length offset by
1772                  * gobbling up any whitespace after it, as well
1773                  */
1774                 i++;
1775                 for (; buf[i] && isspace(buf[i]); i++)
1776                         ; /* do nothing */
1777                 return i;
1778         }
1779         return 0;
1780 }
1781
1782 static int section_name_is_ok(const char *name)
1783 {
1784         /* Empty section names are bogus. */
1785         if (!*name)
1786                 return 0;
1787
1788         /*
1789          * Before a dot, we must be alphanumeric or dash. After the first dot,
1790          * anything goes, so we can stop checking.
1791          */
1792         for (; *name && *name != '.'; name++)
1793                 if (*name != '-' && !isalnum(*name))
1794                         return 0;
1795         return 1;
1796 }
1797
1798 /* if new_name == NULL, the section is removed instead */
1799 int git_config_rename_section_in_file(const char *config_filename,
1800                                       const char *old_name, const char *new_name)
1801 {
1802         int ret = 0, remove = 0;
1803         char *filename_buf = NULL;
1804         struct lock_file *lock;
1805         int out_fd;
1806         char buf[1024];
1807         FILE *config_file;
1808         struct stat st;
1809
1810         if (new_name && !section_name_is_ok(new_name)) {
1811                 ret = error("invalid section name: %s", new_name);
1812                 goto out;
1813         }
1814
1815         if (!config_filename)
1816                 config_filename = filename_buf = git_pathdup("config");
1817
1818         lock = xcalloc(1, sizeof(struct lock_file));
1819         out_fd = hold_lock_file_for_update(lock, config_filename, 0);
1820         if (out_fd < 0) {
1821                 ret = error("could not lock config file %s", config_filename);
1822                 goto out;
1823         }
1824
1825         if (!(config_file = fopen(config_filename, "rb"))) {
1826                 /* no config file means nothing to rename, no error */
1827                 goto unlock_and_out;
1828         }
1829
1830         fstat(fileno(config_file), &st);
1831
1832         if (chmod(lock->filename, st.st_mode & 07777) < 0) {
1833                 ret = error("chmod on %s failed: %s",
1834                                 lock->filename, strerror(errno));
1835                 goto out;
1836         }
1837
1838         while (fgets(buf, sizeof(buf), config_file)) {
1839                 int i;
1840                 int length;
1841                 char *output = buf;
1842                 for (i = 0; buf[i] && isspace(buf[i]); i++)
1843                         ; /* do nothing */
1844                 if (buf[i] == '[') {
1845                         /* it's a section */
1846                         int offset = section_name_match(&buf[i], old_name);
1847                         if (offset > 0) {
1848                                 ret++;
1849                                 if (new_name == NULL) {
1850                                         remove = 1;
1851                                         continue;
1852                                 }
1853                                 store.baselen = strlen(new_name);
1854                                 if (!store_write_section(out_fd, new_name)) {
1855                                         ret = write_error(lock->filename);
1856                                         goto out;
1857                                 }
1858                                 /*
1859                                  * We wrote out the new section, with
1860                                  * a newline, now skip the old
1861                                  * section's length
1862                                  */
1863                                 output += offset + i;
1864                                 if (strlen(output) > 0) {
1865                                         /*
1866                                          * More content means there's
1867                                          * a declaration to put on the
1868                                          * next line; indent with a
1869                                          * tab
1870                                          */
1871                                         output -= 1;
1872                                         output[0] = '\t';
1873                                 }
1874                         }
1875                         remove = 0;
1876                 }
1877                 if (remove)
1878                         continue;
1879                 length = strlen(output);
1880                 if (write_in_full(out_fd, output, length) != length) {
1881                         ret = write_error(lock->filename);
1882                         goto out;
1883                 }
1884         }
1885         fclose(config_file);
1886 unlock_and_out:
1887         if (commit_lock_file(lock) < 0)
1888                 ret = error("could not commit config file %s", config_filename);
1889 out:
1890         free(filename_buf);
1891         return ret;
1892 }
1893
1894 int git_config_rename_section(const char *old_name, const char *new_name)
1895 {
1896         return git_config_rename_section_in_file(NULL, old_name, new_name);
1897 }
1898
1899 /*
1900  * Call this to report error for your variable that should not
1901  * get a boolean value (i.e. "[my] var" means "true").
1902  */
1903 #undef config_error_nonbool
1904 int config_error_nonbool(const char *var)
1905 {
1906         return error("Missing value for '%s'", var);
1907 }
1908
1909 int parse_config_key(const char *var,
1910                      const char *section,
1911                      const char **subsection, int *subsection_len,
1912                      const char **key)
1913 {
1914         int section_len = strlen(section);
1915         const char *dot;
1916
1917         /* Does it start with "section." ? */
1918         if (!starts_with(var, section) || var[section_len] != '.')
1919                 return -1;
1920
1921         /*
1922          * Find the key; we don't know yet if we have a subsection, but we must
1923          * parse backwards from the end, since the subsection may have dots in
1924          * it, too.
1925          */
1926         dot = strrchr(var, '.');
1927         *key = dot + 1;
1928
1929         /* Did we have a subsection at all? */
1930         if (dot == var + section_len) {
1931                 *subsection = NULL;
1932                 *subsection_len = 0;
1933         }
1934         else {
1935                 *subsection = var + section_len + 1;
1936                 *subsection_len = dot - *subsection;
1937         }
1938
1939         return 0;
1940 }