config.con commit Merge branch 'jc/diff-format-doc' into maint (9f8410b)
   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 "lockfile.h"
  10#include "exec_cmd.h"
  11#include "strbuf.h"
  12#include "quote.h"
  13#include "hashmap.h"
  14#include "string-list.h"
  15
  16struct config_source {
  17        struct config_source *prev;
  18        union {
  19                FILE *file;
  20                struct config_buf {
  21                        const char *buf;
  22                        size_t len;
  23                        size_t pos;
  24                } buf;
  25        } u;
  26        const char *name;
  27        const char *path;
  28        int die_on_error;
  29        int linenr;
  30        int eof;
  31        struct strbuf value;
  32        struct strbuf var;
  33
  34        int (*do_fgetc)(struct config_source *c);
  35        int (*do_ungetc)(int c, struct config_source *conf);
  36        long (*do_ftell)(struct config_source *c);
  37};
  38
  39static struct config_source *cf;
  40
  41static int zlib_compression_seen;
  42
  43/*
  44 * Default config_set that contains key-value pairs from the usual set of config
  45 * config files (i.e repo specific .git/config, user wide ~/.gitconfig, XDG
  46 * config file and the global /etc/gitconfig)
  47 */
  48static struct config_set the_config_set;
  49
  50static int config_file_fgetc(struct config_source *conf)
  51{
  52        return fgetc(conf->u.file);
  53}
  54
  55static int config_file_ungetc(int c, struct config_source *conf)
  56{
  57        return ungetc(c, conf->u.file);
  58}
  59
  60static long config_file_ftell(struct config_source *conf)
  61{
  62        return ftell(conf->u.file);
  63}
  64
  65
  66static int config_buf_fgetc(struct config_source *conf)
  67{
  68        if (conf->u.buf.pos < conf->u.buf.len)
  69                return conf->u.buf.buf[conf->u.buf.pos++];
  70
  71        return EOF;
  72}
  73
  74static int config_buf_ungetc(int c, struct config_source *conf)
  75{
  76        if (conf->u.buf.pos > 0)
  77                return conf->u.buf.buf[--conf->u.buf.pos];
  78
  79        return EOF;
  80}
  81
  82static long config_buf_ftell(struct config_source *conf)
  83{
  84        return conf->u.buf.pos;
  85}
  86
  87#define MAX_INCLUDE_DEPTH 10
  88static const char include_depth_advice[] =
  89"exceeded maximum include depth (%d) while including\n"
  90"       %s\n"
  91"from\n"
  92"       %s\n"
  93"Do you have circular includes?";
  94static int handle_path_include(const char *path, struct config_include_data *inc)
  95{
  96        int ret = 0;
  97        struct strbuf buf = STRBUF_INIT;
  98        char *expanded;
  99
 100        if (!path)
 101                return config_error_nonbool("include.path");
 102
 103        expanded = expand_user_path(path);
 104        if (!expanded)
 105                return error("Could not expand include path '%s'", path);
 106        path = expanded;
 107
 108        /*
 109         * Use an absolute path as-is, but interpret relative paths
 110         * based on the including config file.
 111         */
 112        if (!is_absolute_path(path)) {
 113                char *slash;
 114
 115                if (!cf || !cf->path)
 116                        return error("relative config includes must come from files");
 117
 118                slash = find_last_dir_sep(cf->path);
 119                if (slash)
 120                        strbuf_add(&buf, cf->path, slash - cf->path + 1);
 121                strbuf_addstr(&buf, path);
 122                path = buf.buf;
 123        }
 124
 125        if (!access_or_die(path, R_OK, 0)) {
 126                if (++inc->depth > MAX_INCLUDE_DEPTH)
 127                        die(include_depth_advice, MAX_INCLUDE_DEPTH, path,
 128                            cf && cf->name ? cf->name : "the command line");
 129                ret = git_config_from_file(git_config_include, path, inc);
 130                inc->depth--;
 131        }
 132        strbuf_release(&buf);
 133        free(expanded);
 134        return ret;
 135}
 136
 137int git_config_include(const char *var, const char *value, void *data)
 138{
 139        struct config_include_data *inc = data;
 140        int ret;
 141
 142        /*
 143         * Pass along all values, including "include" directives; this makes it
 144         * possible to query information on the includes themselves.
 145         */
 146        ret = inc->fn(var, value, inc->data);
 147        if (ret < 0)
 148                return ret;
 149
 150        if (!strcmp(var, "include.path"))
 151                ret = handle_path_include(value, inc);
 152        return ret;
 153}
 154
 155void 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
 168int git_config_parse_parameter(const char *text,
 169                               config_fn_t fn, void *data)
 170{
 171        const char *value;
 172        struct strbuf **pair;
 173
 174        pair = strbuf_split_str(text, '=', 2);
 175        if (!pair[0])
 176                return error("bogus config parameter: %s", text);
 177
 178        if (pair[0]->len && pair[0]->buf[pair[0]->len - 1] == '=') {
 179                strbuf_setlen(pair[0], pair[0]->len - 1);
 180                value = pair[1] ? pair[1]->buf : "";
 181        } else {
 182                value = NULL;
 183        }
 184
 185        strbuf_trim(pair[0]);
 186        if (!pair[0]->len) {
 187                strbuf_list_free(pair);
 188                return error("bogus config parameter: %s", text);
 189        }
 190        strbuf_tolower(pair[0]);
 191        if (fn(pair[0]->buf, value, data) < 0) {
 192                strbuf_list_free(pair);
 193                return -1;
 194        }
 195        strbuf_list_free(pair);
 196        return 0;
 197}
 198
 199int git_config_from_parameters(config_fn_t fn, void *data)
 200{
 201        const char *env = getenv(CONFIG_DATA_ENVIRONMENT);
 202        char *envw;
 203        const char **argv = NULL;
 204        int nr = 0, alloc = 0;
 205        int i;
 206
 207        if (!env)
 208                return 0;
 209        /* sq_dequote will write over it */
 210        envw = xstrdup(env);
 211
 212        if (sq_dequote_to_argv(envw, &argv, &nr, &alloc) < 0) {
 213                free(envw);
 214                return error("bogus format in " CONFIG_DATA_ENVIRONMENT);
 215        }
 216
 217        for (i = 0; i < nr; i++) {
 218                if (git_config_parse_parameter(argv[i], fn, data) < 0) {
 219                        free(argv);
 220                        free(envw);
 221                        return -1;
 222                }
 223        }
 224
 225        free(argv);
 226        free(envw);
 227        return nr > 0;
 228}
 229
 230static int get_next_char(void)
 231{
 232        int c = cf->do_fgetc(cf);
 233
 234        if (c == '\r') {
 235                /* DOS like systems */
 236                c = cf->do_fgetc(cf);
 237                if (c != '\n') {
 238                        cf->do_ungetc(c, cf);
 239                        c = '\r';
 240                }
 241        }
 242        if (c == '\n')
 243                cf->linenr++;
 244        if (c == EOF) {
 245                cf->eof = 1;
 246                cf->linenr++;
 247                c = '\n';
 248        }
 249        return c;
 250}
 251
 252static char *parse_value(void)
 253{
 254        int quote = 0, comment = 0, space = 0;
 255
 256        strbuf_reset(&cf->value);
 257        for (;;) {
 258                int c = get_next_char();
 259                if (c == '\n') {
 260                        if (quote) {
 261                                cf->linenr--;
 262                                return NULL;
 263                        }
 264                        return cf->value.buf;
 265                }
 266                if (comment)
 267                        continue;
 268                if (isspace(c) && !quote) {
 269                        if (cf->value.len)
 270                                space++;
 271                        continue;
 272                }
 273                if (!quote) {
 274                        if (c == ';' || c == '#') {
 275                                comment = 1;
 276                                continue;
 277                        }
 278                }
 279                for (; space; space--)
 280                        strbuf_addch(&cf->value, ' ');
 281                if (c == '\\') {
 282                        c = get_next_char();
 283                        switch (c) {
 284                        case '\n':
 285                                continue;
 286                        case 't':
 287                                c = '\t';
 288                                break;
 289                        case 'b':
 290                                c = '\b';
 291                                break;
 292                        case 'n':
 293                                c = '\n';
 294                                break;
 295                        /* Some characters escape as themselves */
 296                        case '\\': case '"':
 297                                break;
 298                        /* Reject unknown escape sequences */
 299                        default:
 300                                return NULL;
 301                        }
 302                        strbuf_addch(&cf->value, c);
 303                        continue;
 304                }
 305                if (c == '"') {
 306                        quote = 1-quote;
 307                        continue;
 308                }
 309                strbuf_addch(&cf->value, c);
 310        }
 311}
 312
 313static inline int iskeychar(int c)
 314{
 315        return isalnum(c) || c == '-';
 316}
 317
 318static int get_value(config_fn_t fn, void *data, struct strbuf *name)
 319{
 320        int c;
 321        char *value;
 322        int ret;
 323
 324        /* Get the full name */
 325        for (;;) {
 326                c = get_next_char();
 327                if (cf->eof)
 328                        break;
 329                if (!iskeychar(c))
 330                        break;
 331                strbuf_addch(name, tolower(c));
 332        }
 333
 334        while (c == ' ' || c == '\t')
 335                c = get_next_char();
 336
 337        value = NULL;
 338        if (c != '\n') {
 339                if (c != '=')
 340                        return -1;
 341                value = parse_value();
 342                if (!value)
 343                        return -1;
 344        }
 345        /*
 346         * We already consumed the \n, but we need linenr to point to
 347         * the line we just parsed during the call to fn to get
 348         * accurate line number in error messages.
 349         */
 350        cf->linenr--;
 351        ret = fn(name->buf, value, data);
 352        cf->linenr++;
 353        return ret;
 354}
 355
 356static int get_extended_base_var(struct strbuf *name, int c)
 357{
 358        do {
 359                if (c == '\n')
 360                        goto error_incomplete_line;
 361                c = get_next_char();
 362        } while (isspace(c));
 363
 364        /* We require the format to be '[base "extension"]' */
 365        if (c != '"')
 366                return -1;
 367        strbuf_addch(name, '.');
 368
 369        for (;;) {
 370                int c = get_next_char();
 371                if (c == '\n')
 372                        goto error_incomplete_line;
 373                if (c == '"')
 374                        break;
 375                if (c == '\\') {
 376                        c = get_next_char();
 377                        if (c == '\n')
 378                                goto error_incomplete_line;
 379                }
 380                strbuf_addch(name, c);
 381        }
 382
 383        /* Final ']' */
 384        if (get_next_char() != ']')
 385                return -1;
 386        return 0;
 387error_incomplete_line:
 388        cf->linenr--;
 389        return -1;
 390}
 391
 392static int get_base_var(struct strbuf *name)
 393{
 394        for (;;) {
 395                int c = get_next_char();
 396                if (cf->eof)
 397                        return -1;
 398                if (c == ']')
 399                        return 0;
 400                if (isspace(c))
 401                        return get_extended_base_var(name, c);
 402                if (!iskeychar(c) && c != '.')
 403                        return -1;
 404                strbuf_addch(name, tolower(c));
 405        }
 406}
 407
 408static int git_parse_source(config_fn_t fn, void *data)
 409{
 410        int comment = 0;
 411        int baselen = 0;
 412        struct strbuf *var = &cf->var;
 413
 414        /* U+FEFF Byte Order Mark in UTF8 */
 415        static const unsigned char *utf8_bom = (unsigned char *) "\xef\xbb\xbf";
 416        const unsigned char *bomptr = utf8_bom;
 417
 418        for (;;) {
 419                int c = get_next_char();
 420                if (bomptr && *bomptr) {
 421                        /* We are at the file beginning; skip UTF8-encoded BOM
 422                         * if present. Sane editors won't put this in on their
 423                         * own, but e.g. Windows Notepad will do it happily. */
 424                        if ((unsigned char) c == *bomptr) {
 425                                bomptr++;
 426                                continue;
 427                        } else {
 428                                /* Do not tolerate partial BOM. */
 429                                if (bomptr != utf8_bom)
 430                                        break;
 431                                /* No BOM at file beginning. Cool. */
 432                                bomptr = NULL;
 433                        }
 434                }
 435                if (c == '\n') {
 436                        if (cf->eof)
 437                                return 0;
 438                        comment = 0;
 439                        continue;
 440                }
 441                if (comment || isspace(c))
 442                        continue;
 443                if (c == '#' || c == ';') {
 444                        comment = 1;
 445                        continue;
 446                }
 447                if (c == '[') {
 448                        /* Reset prior to determining a new stem */
 449                        strbuf_reset(var);
 450                        if (get_base_var(var) < 0 || var->len < 1)
 451                                break;
 452                        strbuf_addch(var, '.');
 453                        baselen = var->len;
 454                        continue;
 455                }
 456                if (!isalpha(c))
 457                        break;
 458                /*
 459                 * Truncate the var name back to the section header
 460                 * stem prior to grabbing the suffix part of the name
 461                 * and the value.
 462                 */
 463                strbuf_setlen(var, baselen);
 464                strbuf_addch(var, tolower(c));
 465                if (get_value(fn, data, var) < 0)
 466                        break;
 467        }
 468        if (cf->die_on_error)
 469                die(_("bad config file line %d in %s"), cf->linenr, cf->name);
 470        else
 471                return error(_("bad config file line %d in %s"), cf->linenr, cf->name);
 472}
 473
 474static int parse_unit_factor(const char *end, uintmax_t *val)
 475{
 476        if (!*end)
 477                return 1;
 478        else if (!strcasecmp(end, "k")) {
 479                *val *= 1024;
 480                return 1;
 481        }
 482        else if (!strcasecmp(end, "m")) {
 483                *val *= 1024 * 1024;
 484                return 1;
 485        }
 486        else if (!strcasecmp(end, "g")) {
 487                *val *= 1024 * 1024 * 1024;
 488                return 1;
 489        }
 490        return 0;
 491}
 492
 493static int git_parse_signed(const char *value, intmax_t *ret, intmax_t max)
 494{
 495        if (value && *value) {
 496                char *end;
 497                intmax_t val;
 498                uintmax_t uval;
 499                uintmax_t factor = 1;
 500
 501                errno = 0;
 502                val = strtoimax(value, &end, 0);
 503                if (errno == ERANGE)
 504                        return 0;
 505                if (!parse_unit_factor(end, &factor)) {
 506                        errno = EINVAL;
 507                        return 0;
 508                }
 509                uval = labs(val);
 510                uval *= factor;
 511                if (uval > max || labs(val) > uval) {
 512                        errno = ERANGE;
 513                        return 0;
 514                }
 515                val *= factor;
 516                *ret = val;
 517                return 1;
 518        }
 519        errno = EINVAL;
 520        return 0;
 521}
 522
 523static int git_parse_unsigned(const char *value, uintmax_t *ret, uintmax_t max)
 524{
 525        if (value && *value) {
 526                char *end;
 527                uintmax_t val;
 528                uintmax_t oldval;
 529
 530                errno = 0;
 531                val = strtoumax(value, &end, 0);
 532                if (errno == ERANGE)
 533                        return 0;
 534                oldval = val;
 535                if (!parse_unit_factor(end, &val)) {
 536                        errno = EINVAL;
 537                        return 0;
 538                }
 539                if (val > max || oldval > val) {
 540                        errno = ERANGE;
 541                        return 0;
 542                }
 543                *ret = val;
 544                return 1;
 545        }
 546        errno = EINVAL;
 547        return 0;
 548}
 549
 550static int git_parse_int(const char *value, int *ret)
 551{
 552        intmax_t tmp;
 553        if (!git_parse_signed(value, &tmp, maximum_signed_value_of_type(int)))
 554                return 0;
 555        *ret = tmp;
 556        return 1;
 557}
 558
 559static int git_parse_int64(const char *value, int64_t *ret)
 560{
 561        intmax_t tmp;
 562        if (!git_parse_signed(value, &tmp, maximum_signed_value_of_type(int64_t)))
 563                return 0;
 564        *ret = tmp;
 565        return 1;
 566}
 567
 568int git_parse_ulong(const char *value, unsigned long *ret)
 569{
 570        uintmax_t tmp;
 571        if (!git_parse_unsigned(value, &tmp, maximum_unsigned_value_of_type(long)))
 572                return 0;
 573        *ret = tmp;
 574        return 1;
 575}
 576
 577NORETURN
 578static void die_bad_number(const char *name, const char *value)
 579{
 580        const char *reason = errno == ERANGE ?
 581                             "out of range" :
 582                             "invalid unit";
 583        if (!value)
 584                value = "";
 585
 586        if (cf && cf->name)
 587                die(_("bad numeric config value '%s' for '%s' in %s: %s"),
 588                    value, name, cf->name, reason);
 589        die(_("bad numeric config value '%s' for '%s': %s"), value, name, reason);
 590}
 591
 592int git_config_int(const char *name, const char *value)
 593{
 594        int ret;
 595        if (!git_parse_int(value, &ret))
 596                die_bad_number(name, value);
 597        return ret;
 598}
 599
 600int64_t git_config_int64(const char *name, const char *value)
 601{
 602        int64_t ret;
 603        if (!git_parse_int64(value, &ret))
 604                die_bad_number(name, value);
 605        return ret;
 606}
 607
 608unsigned long git_config_ulong(const char *name, const char *value)
 609{
 610        unsigned long ret;
 611        if (!git_parse_ulong(value, &ret))
 612                die_bad_number(name, value);
 613        return ret;
 614}
 615
 616static int git_config_maybe_bool_text(const char *name, const char *value)
 617{
 618        if (!value)
 619                return 1;
 620        if (!*value)
 621                return 0;
 622        if (!strcasecmp(value, "true")
 623            || !strcasecmp(value, "yes")
 624            || !strcasecmp(value, "on"))
 625                return 1;
 626        if (!strcasecmp(value, "false")
 627            || !strcasecmp(value, "no")
 628            || !strcasecmp(value, "off"))
 629                return 0;
 630        return -1;
 631}
 632
 633int git_config_maybe_bool(const char *name, const char *value)
 634{
 635        int v = git_config_maybe_bool_text(name, value);
 636        if (0 <= v)
 637                return v;
 638        if (git_parse_int(value, &v))
 639                return !!v;
 640        return -1;
 641}
 642
 643int git_config_bool_or_int(const char *name, const char *value, int *is_bool)
 644{
 645        int v = git_config_maybe_bool_text(name, value);
 646        if (0 <= v) {
 647                *is_bool = 1;
 648                return v;
 649        }
 650        *is_bool = 0;
 651        return git_config_int(name, value);
 652}
 653
 654int git_config_bool(const char *name, const char *value)
 655{
 656        int discard;
 657        return !!git_config_bool_or_int(name, value, &discard);
 658}
 659
 660int git_config_string(const char **dest, const char *var, const char *value)
 661{
 662        if (!value)
 663                return config_error_nonbool(var);
 664        *dest = xstrdup(value);
 665        return 0;
 666}
 667
 668int git_config_pathname(const char **dest, const char *var, const char *value)
 669{
 670        if (!value)
 671                return config_error_nonbool(var);
 672        *dest = expand_user_path(value);
 673        if (!*dest)
 674                die(_("failed to expand user dir in: '%s'"), value);
 675        return 0;
 676}
 677
 678static int git_default_core_config(const char *var, const char *value)
 679{
 680        /* This needs a better name */
 681        if (!strcmp(var, "core.filemode")) {
 682                trust_executable_bit = git_config_bool(var, value);
 683                return 0;
 684        }
 685        if (!strcmp(var, "core.trustctime")) {
 686                trust_ctime = git_config_bool(var, value);
 687                return 0;
 688        }
 689        if (!strcmp(var, "core.checkstat")) {
 690                if (!strcasecmp(value, "default"))
 691                        check_stat = 1;
 692                else if (!strcasecmp(value, "minimal"))
 693                        check_stat = 0;
 694        }
 695
 696        if (!strcmp(var, "core.quotepath")) {
 697                quote_path_fully = git_config_bool(var, value);
 698                return 0;
 699        }
 700
 701        if (!strcmp(var, "core.symlinks")) {
 702                has_symlinks = git_config_bool(var, value);
 703                return 0;
 704        }
 705
 706        if (!strcmp(var, "core.ignorecase")) {
 707                ignore_case = git_config_bool(var, value);
 708                return 0;
 709        }
 710
 711        if (!strcmp(var, "core.attributesfile"))
 712                return git_config_pathname(&git_attributes_file, var, value);
 713
 714        if (!strcmp(var, "core.bare")) {
 715                is_bare_repository_cfg = git_config_bool(var, value);
 716                return 0;
 717        }
 718
 719        if (!strcmp(var, "core.ignorestat")) {
 720                assume_unchanged = git_config_bool(var, value);
 721                return 0;
 722        }
 723
 724        if (!strcmp(var, "core.prefersymlinkrefs")) {
 725                prefer_symlink_refs = git_config_bool(var, value);
 726                return 0;
 727        }
 728
 729        if (!strcmp(var, "core.logallrefupdates")) {
 730                log_all_ref_updates = git_config_bool(var, value);
 731                return 0;
 732        }
 733
 734        if (!strcmp(var, "core.warnambiguousrefs")) {
 735                warn_ambiguous_refs = git_config_bool(var, value);
 736                return 0;
 737        }
 738
 739        if (!strcmp(var, "core.abbrev")) {
 740                int abbrev = git_config_int(var, value);
 741                if (abbrev < minimum_abbrev || abbrev > 40)
 742                        return -1;
 743                default_abbrev = abbrev;
 744                return 0;
 745        }
 746
 747        if (!strcmp(var, "core.loosecompression")) {
 748                int level = git_config_int(var, value);
 749                if (level == -1)
 750                        level = Z_DEFAULT_COMPRESSION;
 751                else if (level < 0 || level > Z_BEST_COMPRESSION)
 752                        die(_("bad zlib compression level %d"), level);
 753                zlib_compression_level = level;
 754                zlib_compression_seen = 1;
 755                return 0;
 756        }
 757
 758        if (!strcmp(var, "core.compression")) {
 759                int level = git_config_int(var, value);
 760                if (level == -1)
 761                        level = Z_DEFAULT_COMPRESSION;
 762                else if (level < 0 || level > Z_BEST_COMPRESSION)
 763                        die(_("bad zlib compression level %d"), level);
 764                core_compression_level = level;
 765                core_compression_seen = 1;
 766                if (!zlib_compression_seen)
 767                        zlib_compression_level = level;
 768                return 0;
 769        }
 770
 771        if (!strcmp(var, "core.packedgitwindowsize")) {
 772                int pgsz_x2 = getpagesize() * 2;
 773                packed_git_window_size = git_config_ulong(var, value);
 774
 775                /* This value must be multiple of (pagesize * 2) */
 776                packed_git_window_size /= pgsz_x2;
 777                if (packed_git_window_size < 1)
 778                        packed_git_window_size = 1;
 779                packed_git_window_size *= pgsz_x2;
 780                return 0;
 781        }
 782
 783        if (!strcmp(var, "core.bigfilethreshold")) {
 784                big_file_threshold = git_config_ulong(var, value);
 785                return 0;
 786        }
 787
 788        if (!strcmp(var, "core.packedgitlimit")) {
 789                packed_git_limit = git_config_ulong(var, value);
 790                return 0;
 791        }
 792
 793        if (!strcmp(var, "core.deltabasecachelimit")) {
 794                delta_base_cache_limit = git_config_ulong(var, value);
 795                return 0;
 796        }
 797
 798        if (!strcmp(var, "core.autocrlf")) {
 799                if (value && !strcasecmp(value, "input")) {
 800                        if (core_eol == EOL_CRLF)
 801                                return error("core.autocrlf=input conflicts with core.eol=crlf");
 802                        auto_crlf = AUTO_CRLF_INPUT;
 803                        return 0;
 804                }
 805                auto_crlf = git_config_bool(var, value);
 806                return 0;
 807        }
 808
 809        if (!strcmp(var, "core.safecrlf")) {
 810                if (value && !strcasecmp(value, "warn")) {
 811                        safe_crlf = SAFE_CRLF_WARN;
 812                        return 0;
 813                }
 814                safe_crlf = git_config_bool(var, value);
 815                return 0;
 816        }
 817
 818        if (!strcmp(var, "core.eol")) {
 819                if (value && !strcasecmp(value, "lf"))
 820                        core_eol = EOL_LF;
 821                else if (value && !strcasecmp(value, "crlf"))
 822                        core_eol = EOL_CRLF;
 823                else if (value && !strcasecmp(value, "native"))
 824                        core_eol = EOL_NATIVE;
 825                else
 826                        core_eol = EOL_UNSET;
 827                if (core_eol == EOL_CRLF && auto_crlf == AUTO_CRLF_INPUT)
 828                        return error("core.autocrlf=input conflicts with core.eol=crlf");
 829                return 0;
 830        }
 831
 832        if (!strcmp(var, "core.notesref")) {
 833                notes_ref_name = xstrdup(value);
 834                return 0;
 835        }
 836
 837        if (!strcmp(var, "core.pager"))
 838                return git_config_string(&pager_program, var, value);
 839
 840        if (!strcmp(var, "core.editor"))
 841                return git_config_string(&editor_program, var, value);
 842
 843        if (!strcmp(var, "core.commentchar")) {
 844                if (!value)
 845                        return config_error_nonbool(var);
 846                else if (!strcasecmp(value, "auto"))
 847                        auto_comment_line_char = 1;
 848                else if (value[0] && !value[1]) {
 849                        comment_line_char = value[0];
 850                        auto_comment_line_char = 0;
 851                } else
 852                        return error("core.commentChar should only be one character");
 853                return 0;
 854        }
 855
 856        if (!strcmp(var, "core.askpass"))
 857                return git_config_string(&askpass_program, var, value);
 858
 859        if (!strcmp(var, "core.excludesfile"))
 860                return git_config_pathname(&excludes_file, var, value);
 861
 862        if (!strcmp(var, "core.whitespace")) {
 863                if (!value)
 864                        return config_error_nonbool(var);
 865                whitespace_rule_cfg = parse_whitespace_rule(value);
 866                return 0;
 867        }
 868
 869        if (!strcmp(var, "core.fsyncobjectfiles")) {
 870                fsync_object_files = git_config_bool(var, value);
 871                return 0;
 872        }
 873
 874        if (!strcmp(var, "core.preloadindex")) {
 875                core_preload_index = git_config_bool(var, value);
 876                return 0;
 877        }
 878
 879        if (!strcmp(var, "core.createobject")) {
 880                if (!strcmp(value, "rename"))
 881                        object_creation_mode = OBJECT_CREATION_USES_RENAMES;
 882                else if (!strcmp(value, "link"))
 883                        object_creation_mode = OBJECT_CREATION_USES_HARDLINKS;
 884                else
 885                        die(_("invalid mode for object creation: %s"), value);
 886                return 0;
 887        }
 888
 889        if (!strcmp(var, "core.sparsecheckout")) {
 890                core_apply_sparse_checkout = git_config_bool(var, value);
 891                return 0;
 892        }
 893
 894        if (!strcmp(var, "core.precomposeunicode")) {
 895                precomposed_unicode = git_config_bool(var, value);
 896                return 0;
 897        }
 898
 899        if (!strcmp(var, "core.protecthfs")) {
 900                protect_hfs = git_config_bool(var, value);
 901                return 0;
 902        }
 903
 904        if (!strcmp(var, "core.protectntfs")) {
 905                protect_ntfs = git_config_bool(var, value);
 906                return 0;
 907        }
 908
 909        /* Add other config variables here and to Documentation/config.txt. */
 910        return 0;
 911}
 912
 913static int git_default_i18n_config(const char *var, const char *value)
 914{
 915        if (!strcmp(var, "i18n.commitencoding"))
 916                return git_config_string(&git_commit_encoding, var, value);
 917
 918        if (!strcmp(var, "i18n.logoutputencoding"))
 919                return git_config_string(&git_log_output_encoding, var, value);
 920
 921        /* Add other config variables here and to Documentation/config.txt. */
 922        return 0;
 923}
 924
 925static int git_default_branch_config(const char *var, const char *value)
 926{
 927        if (!strcmp(var, "branch.autosetupmerge")) {
 928                if (value && !strcasecmp(value, "always")) {
 929                        git_branch_track = BRANCH_TRACK_ALWAYS;
 930                        return 0;
 931                }
 932                git_branch_track = git_config_bool(var, value);
 933                return 0;
 934        }
 935        if (!strcmp(var, "branch.autosetuprebase")) {
 936                if (!value)
 937                        return config_error_nonbool(var);
 938                else if (!strcmp(value, "never"))
 939                        autorebase = AUTOREBASE_NEVER;
 940                else if (!strcmp(value, "local"))
 941                        autorebase = AUTOREBASE_LOCAL;
 942                else if (!strcmp(value, "remote"))
 943                        autorebase = AUTOREBASE_REMOTE;
 944                else if (!strcmp(value, "always"))
 945                        autorebase = AUTOREBASE_ALWAYS;
 946                else
 947                        return error("Malformed value for %s", var);
 948                return 0;
 949        }
 950
 951        /* Add other config variables here and to Documentation/config.txt. */
 952        return 0;
 953}
 954
 955static int git_default_push_config(const char *var, const char *value)
 956{
 957        if (!strcmp(var, "push.default")) {
 958                if (!value)
 959                        return config_error_nonbool(var);
 960                else if (!strcmp(value, "nothing"))
 961                        push_default = PUSH_DEFAULT_NOTHING;
 962                else if (!strcmp(value, "matching"))
 963                        push_default = PUSH_DEFAULT_MATCHING;
 964                else if (!strcmp(value, "simple"))
 965                        push_default = PUSH_DEFAULT_SIMPLE;
 966                else if (!strcmp(value, "upstream"))
 967                        push_default = PUSH_DEFAULT_UPSTREAM;
 968                else if (!strcmp(value, "tracking")) /* deprecated */
 969                        push_default = PUSH_DEFAULT_UPSTREAM;
 970                else if (!strcmp(value, "current"))
 971                        push_default = PUSH_DEFAULT_CURRENT;
 972                else {
 973                        error("Malformed value for %s: %s", var, value);
 974                        return error("Must be one of nothing, matching, simple, "
 975                                     "upstream or current.");
 976                }
 977                return 0;
 978        }
 979
 980        /* Add other config variables here and to Documentation/config.txt. */
 981        return 0;
 982}
 983
 984static int git_default_mailmap_config(const char *var, const char *value)
 985{
 986        if (!strcmp(var, "mailmap.file"))
 987                return git_config_pathname(&git_mailmap_file, var, value);
 988        if (!strcmp(var, "mailmap.blob"))
 989                return git_config_string(&git_mailmap_blob, var, value);
 990
 991        /* Add other config variables here and to Documentation/config.txt. */
 992        return 0;
 993}
 994
 995int git_default_config(const char *var, const char *value, void *dummy)
 996{
 997        if (starts_with(var, "core."))
 998                return git_default_core_config(var, value);
 999
1000        if (starts_with(var, "user."))
1001                return git_ident_config(var, value, dummy);
1002
1003        if (starts_with(var, "i18n."))
1004                return git_default_i18n_config(var, value);
1005
1006        if (starts_with(var, "branch."))
1007                return git_default_branch_config(var, value);
1008
1009        if (starts_with(var, "push."))
1010                return git_default_push_config(var, value);
1011
1012        if (starts_with(var, "mailmap."))
1013                return git_default_mailmap_config(var, value);
1014
1015        if (starts_with(var, "advice."))
1016                return git_default_advice_config(var, value);
1017
1018        if (!strcmp(var, "pager.color") || !strcmp(var, "color.pager")) {
1019                pager_use_color = git_config_bool(var,value);
1020                return 0;
1021        }
1022
1023        if (!strcmp(var, "pack.packsizelimit")) {
1024                pack_size_limit_cfg = git_config_ulong(var, value);
1025                return 0;
1026        }
1027        /* Add other config variables here and to Documentation/config.txt. */
1028        return 0;
1029}
1030
1031/*
1032 * All source specific fields in the union, die_on_error, name and the callbacks
1033 * fgetc, ungetc, ftell of top need to be initialized before calling
1034 * this function.
1035 */
1036static int do_config_from(struct config_source *top, config_fn_t fn, void *data)
1037{
1038        int ret;
1039
1040        /* push config-file parsing state stack */
1041        top->prev = cf;
1042        top->linenr = 1;
1043        top->eof = 0;
1044        strbuf_init(&top->value, 1024);
1045        strbuf_init(&top->var, 1024);
1046        cf = top;
1047
1048        ret = git_parse_source(fn, data);
1049
1050        /* pop config-file parsing state stack */
1051        strbuf_release(&top->value);
1052        strbuf_release(&top->var);
1053        cf = top->prev;
1054
1055        return ret;
1056}
1057
1058static int do_config_from_file(config_fn_t fn,
1059                const char *name, const char *path, FILE *f, void *data)
1060{
1061        struct config_source top;
1062
1063        top.u.file = f;
1064        top.name = name;
1065        top.path = path;
1066        top.die_on_error = 1;
1067        top.do_fgetc = config_file_fgetc;
1068        top.do_ungetc = config_file_ungetc;
1069        top.do_ftell = config_file_ftell;
1070
1071        return do_config_from(&top, fn, data);
1072}
1073
1074static int git_config_from_stdin(config_fn_t fn, void *data)
1075{
1076        return do_config_from_file(fn, "<stdin>", NULL, stdin, data);
1077}
1078
1079int git_config_from_file(config_fn_t fn, const char *filename, void *data)
1080{
1081        int ret = -1;
1082        FILE *f;
1083
1084        f = fopen(filename, "r");
1085        if (f) {
1086                ret = do_config_from_file(fn, filename, filename, f, data);
1087                fclose(f);
1088        }
1089        return ret;
1090}
1091
1092int git_config_from_buf(config_fn_t fn, const char *name, const char *buf,
1093                        size_t len, void *data)
1094{
1095        struct config_source top;
1096
1097        top.u.buf.buf = buf;
1098        top.u.buf.len = len;
1099        top.u.buf.pos = 0;
1100        top.name = name;
1101        top.path = NULL;
1102        top.die_on_error = 0;
1103        top.do_fgetc = config_buf_fgetc;
1104        top.do_ungetc = config_buf_ungetc;
1105        top.do_ftell = config_buf_ftell;
1106
1107        return do_config_from(&top, fn, data);
1108}
1109
1110static int git_config_from_blob_sha1(config_fn_t fn,
1111                                     const char *name,
1112                                     const unsigned char *sha1,
1113                                     void *data)
1114{
1115        enum object_type type;
1116        char *buf;
1117        unsigned long size;
1118        int ret;
1119
1120        buf = read_sha1_file(sha1, &type, &size);
1121        if (!buf)
1122                return error("unable to load config blob object '%s'", name);
1123        if (type != OBJ_BLOB) {
1124                free(buf);
1125                return error("reference '%s' does not point to a blob", name);
1126        }
1127
1128        ret = git_config_from_buf(fn, name, buf, size, data);
1129        free(buf);
1130
1131        return ret;
1132}
1133
1134static int git_config_from_blob_ref(config_fn_t fn,
1135                                    const char *name,
1136                                    void *data)
1137{
1138        unsigned char sha1[20];
1139
1140        if (get_sha1(name, sha1) < 0)
1141                return error("unable to resolve config blob '%s'", name);
1142        return git_config_from_blob_sha1(fn, name, sha1, data);
1143}
1144
1145const char *git_etc_gitconfig(void)
1146{
1147        static const char *system_wide;
1148        if (!system_wide)
1149                system_wide = system_path(ETC_GITCONFIG);
1150        return system_wide;
1151}
1152
1153/*
1154 * Parse environment variable 'k' as a boolean (in various
1155 * possible spellings); if missing, use the default value 'def'.
1156 */
1157int git_env_bool(const char *k, int def)
1158{
1159        const char *v = getenv(k);
1160        return v ? git_config_bool(k, v) : def;
1161}
1162
1163/*
1164 * Parse environment variable 'k' as ulong with possibly a unit
1165 * suffix; if missing, use the default value 'val'.
1166 */
1167unsigned long git_env_ulong(const char *k, unsigned long val)
1168{
1169        const char *v = getenv(k);
1170        if (v && !git_parse_ulong(v, &val))
1171                die("failed to parse %s", k);
1172        return val;
1173}
1174
1175int git_config_system(void)
1176{
1177        return !git_env_bool("GIT_CONFIG_NOSYSTEM", 0);
1178}
1179
1180int git_config_early(config_fn_t fn, void *data, const char *repo_config)
1181{
1182        int ret = 0, found = 0;
1183        char *xdg_config = NULL;
1184        char *user_config = NULL;
1185
1186        home_config_paths(&user_config, &xdg_config, "config");
1187
1188        if (git_config_system() && !access_or_die(git_etc_gitconfig(), R_OK, 0)) {
1189                ret += git_config_from_file(fn, git_etc_gitconfig(),
1190                                            data);
1191                found += 1;
1192        }
1193
1194        if (xdg_config && !access_or_die(xdg_config, R_OK, ACCESS_EACCES_OK)) {
1195                ret += git_config_from_file(fn, xdg_config, data);
1196                found += 1;
1197        }
1198
1199        if (user_config && !access_or_die(user_config, R_OK, ACCESS_EACCES_OK)) {
1200                ret += git_config_from_file(fn, user_config, data);
1201                found += 1;
1202        }
1203
1204        if (repo_config && !access_or_die(repo_config, R_OK, 0)) {
1205                ret += git_config_from_file(fn, repo_config, data);
1206                found += 1;
1207        }
1208
1209        switch (git_config_from_parameters(fn, data)) {
1210        case -1: /* error */
1211                die(_("unable to parse command-line config"));
1212                break;
1213        case 0: /* found nothing */
1214                break;
1215        default: /* found at least one item */
1216                found++;
1217                break;
1218        }
1219
1220        free(xdg_config);
1221        free(user_config);
1222        return ret == 0 ? found : ret;
1223}
1224
1225int git_config_with_options(config_fn_t fn, void *data,
1226                            struct git_config_source *config_source,
1227                            int respect_includes)
1228{
1229        char *repo_config = NULL;
1230        int ret;
1231        struct config_include_data inc = CONFIG_INCLUDE_INIT;
1232
1233        if (respect_includes) {
1234                inc.fn = fn;
1235                inc.data = data;
1236                fn = git_config_include;
1237                data = &inc;
1238        }
1239
1240        /*
1241         * If we have a specific filename, use it. Otherwise, follow the
1242         * regular lookup sequence.
1243         */
1244        if (config_source && config_source->use_stdin)
1245                return git_config_from_stdin(fn, data);
1246        else if (config_source && config_source->file)
1247                return git_config_from_file(fn, config_source->file, data);
1248        else if (config_source && config_source->blob)
1249                return git_config_from_blob_ref(fn, config_source->blob, data);
1250
1251        repo_config = git_pathdup("config");
1252        ret = git_config_early(fn, data, repo_config);
1253        if (repo_config)
1254                free(repo_config);
1255        return ret;
1256}
1257
1258static void git_config_raw(config_fn_t fn, void *data)
1259{
1260        if (git_config_with_options(fn, data, NULL, 1) < 0)
1261                /*
1262                 * git_config_with_options() normally returns only
1263                 * positive values, as most errors are fatal, and
1264                 * non-fatal potential errors are guarded by "if"
1265                 * statements that are entered only when no error is
1266                 * possible.
1267                 *
1268                 * If we ever encounter a non-fatal error, it means
1269                 * something went really wrong and we should stop
1270                 * immediately.
1271                 */
1272                die(_("unknown error occured while reading the configuration files"));
1273}
1274
1275static void configset_iter(struct config_set *cs, config_fn_t fn, void *data)
1276{
1277        int i, value_index;
1278        struct string_list *values;
1279        struct config_set_element *entry;
1280        struct configset_list *list = &cs->list;
1281        struct key_value_info *kv_info;
1282
1283        for (i = 0; i < list->nr; i++) {
1284                entry = list->items[i].e;
1285                value_index = list->items[i].value_index;
1286                values = &entry->value_list;
1287                if (fn(entry->key, values->items[value_index].string, data) < 0) {
1288                        kv_info = values->items[value_index].util;
1289                        git_die_config_linenr(entry->key, kv_info->filename, kv_info->linenr);
1290                }
1291        }
1292}
1293
1294static void git_config_check_init(void);
1295
1296void git_config(config_fn_t fn, void *data)
1297{
1298        git_config_check_init();
1299        configset_iter(&the_config_set, fn, data);
1300}
1301
1302static struct config_set_element *configset_find_element(struct config_set *cs, const char *key)
1303{
1304        struct config_set_element k;
1305        struct config_set_element *found_entry;
1306        char *normalized_key;
1307        int ret;
1308        /*
1309         * `key` may come from the user, so normalize it before using it
1310         * for querying entries from the hashmap.
1311         */
1312        ret = git_config_parse_key(key, &normalized_key, NULL);
1313
1314        if (ret)
1315                return NULL;
1316
1317        hashmap_entry_init(&k, strhash(normalized_key));
1318        k.key = normalized_key;
1319        found_entry = hashmap_get(&cs->config_hash, &k, NULL);
1320        free(normalized_key);
1321        return found_entry;
1322}
1323
1324static int configset_add_value(struct config_set *cs, const char *key, const char *value)
1325{
1326        struct config_set_element *e;
1327        struct string_list_item *si;
1328        struct configset_list_item *l_item;
1329        struct key_value_info *kv_info = xmalloc(sizeof(*kv_info));
1330
1331        e = configset_find_element(cs, key);
1332        /*
1333         * Since the keys are being fed by git_config*() callback mechanism, they
1334         * are already normalized. So simply add them without any further munging.
1335         */
1336        if (!e) {
1337                e = xmalloc(sizeof(*e));
1338                hashmap_entry_init(e, strhash(key));
1339                e->key = xstrdup(key);
1340                string_list_init(&e->value_list, 1);
1341                hashmap_add(&cs->config_hash, e);
1342        }
1343        si = string_list_append_nodup(&e->value_list, xstrdup_or_null(value));
1344
1345        ALLOC_GROW(cs->list.items, cs->list.nr + 1, cs->list.alloc);
1346        l_item = &cs->list.items[cs->list.nr++];
1347        l_item->e = e;
1348        l_item->value_index = e->value_list.nr - 1;
1349
1350        if (cf) {
1351                kv_info->filename = strintern(cf->name);
1352                kv_info->linenr = cf->linenr;
1353        } else {
1354                /* for values read from `git_config_from_parameters()` */
1355                kv_info->filename = NULL;
1356                kv_info->linenr = -1;
1357        }
1358        si->util = kv_info;
1359
1360        return 0;
1361}
1362
1363static int config_set_element_cmp(const struct config_set_element *e1,
1364                                 const struct config_set_element *e2, const void *unused)
1365{
1366        return strcmp(e1->key, e2->key);
1367}
1368
1369void git_configset_init(struct config_set *cs)
1370{
1371        hashmap_init(&cs->config_hash, (hashmap_cmp_fn)config_set_element_cmp, 0);
1372        cs->hash_initialized = 1;
1373        cs->list.nr = 0;
1374        cs->list.alloc = 0;
1375        cs->list.items = NULL;
1376}
1377
1378void git_configset_clear(struct config_set *cs)
1379{
1380        struct config_set_element *entry;
1381        struct hashmap_iter iter;
1382        if (!cs->hash_initialized)
1383                return;
1384
1385        hashmap_iter_init(&cs->config_hash, &iter);
1386        while ((entry = hashmap_iter_next(&iter))) {
1387                free(entry->key);
1388                string_list_clear(&entry->value_list, 1);
1389        }
1390        hashmap_free(&cs->config_hash, 1);
1391        cs->hash_initialized = 0;
1392        free(cs->list.items);
1393        cs->list.nr = 0;
1394        cs->list.alloc = 0;
1395        cs->list.items = NULL;
1396}
1397
1398static int config_set_callback(const char *key, const char *value, void *cb)
1399{
1400        struct config_set *cs = cb;
1401        configset_add_value(cs, key, value);
1402        return 0;
1403}
1404
1405int git_configset_add_file(struct config_set *cs, const char *filename)
1406{
1407        return git_config_from_file(config_set_callback, filename, cs);
1408}
1409
1410int git_configset_get_value(struct config_set *cs, const char *key, const char **value)
1411{
1412        const struct string_list *values = NULL;
1413        /*
1414         * Follows "last one wins" semantic, i.e., if there are multiple matches for the
1415         * queried key in the files of the configset, the value returned will be the last
1416         * value in the value list for that key.
1417         */
1418        values = git_configset_get_value_multi(cs, key);
1419
1420        if (!values)
1421                return 1;
1422        assert(values->nr > 0);
1423        *value = values->items[values->nr - 1].string;
1424        return 0;
1425}
1426
1427const struct string_list *git_configset_get_value_multi(struct config_set *cs, const char *key)
1428{
1429        struct config_set_element *e = configset_find_element(cs, key);
1430        return e ? &e->value_list : NULL;
1431}
1432
1433int git_configset_get_string_const(struct config_set *cs, const char *key, const char **dest)
1434{
1435        const char *value;
1436        if (!git_configset_get_value(cs, key, &value))
1437                return git_config_string(dest, key, value);
1438        else
1439                return 1;
1440}
1441
1442int git_configset_get_string(struct config_set *cs, const char *key, char **dest)
1443{
1444        return git_configset_get_string_const(cs, key, (const char **)dest);
1445}
1446
1447int git_configset_get_int(struct config_set *cs, const char *key, int *dest)
1448{
1449        const char *value;
1450        if (!git_configset_get_value(cs, key, &value)) {
1451                *dest = git_config_int(key, value);
1452                return 0;
1453        } else
1454                return 1;
1455}
1456
1457int git_configset_get_ulong(struct config_set *cs, const char *key, unsigned long *dest)
1458{
1459        const char *value;
1460        if (!git_configset_get_value(cs, key, &value)) {
1461                *dest = git_config_ulong(key, value);
1462                return 0;
1463        } else
1464                return 1;
1465}
1466
1467int git_configset_get_bool(struct config_set *cs, const char *key, int *dest)
1468{
1469        const char *value;
1470        if (!git_configset_get_value(cs, key, &value)) {
1471                *dest = git_config_bool(key, value);
1472                return 0;
1473        } else
1474                return 1;
1475}
1476
1477int git_configset_get_bool_or_int(struct config_set *cs, const char *key,
1478                                int *is_bool, int *dest)
1479{
1480        const char *value;
1481        if (!git_configset_get_value(cs, key, &value)) {
1482                *dest = git_config_bool_or_int(key, value, is_bool);
1483                return 0;
1484        } else
1485                return 1;
1486}
1487
1488int git_configset_get_maybe_bool(struct config_set *cs, const char *key, int *dest)
1489{
1490        const char *value;
1491        if (!git_configset_get_value(cs, key, &value)) {
1492                *dest = git_config_maybe_bool(key, value);
1493                if (*dest == -1)
1494                        return -1;
1495                return 0;
1496        } else
1497                return 1;
1498}
1499
1500int git_configset_get_pathname(struct config_set *cs, const char *key, const char **dest)
1501{
1502        const char *value;
1503        if (!git_configset_get_value(cs, key, &value))
1504                return git_config_pathname(dest, key, value);
1505        else
1506                return 1;
1507}
1508
1509static void git_config_check_init(void)
1510{
1511        if (the_config_set.hash_initialized)
1512                return;
1513        git_configset_init(&the_config_set);
1514        git_config_raw(config_set_callback, &the_config_set);
1515}
1516
1517void git_config_clear(void)
1518{
1519        if (!the_config_set.hash_initialized)
1520                return;
1521        git_configset_clear(&the_config_set);
1522}
1523
1524int git_config_get_value(const char *key, const char **value)
1525{
1526        git_config_check_init();
1527        return git_configset_get_value(&the_config_set, key, value);
1528}
1529
1530const struct string_list *git_config_get_value_multi(const char *key)
1531{
1532        git_config_check_init();
1533        return git_configset_get_value_multi(&the_config_set, key);
1534}
1535
1536int git_config_get_string_const(const char *key, const char **dest)
1537{
1538        int ret;
1539        git_config_check_init();
1540        ret = git_configset_get_string_const(&the_config_set, key, dest);
1541        if (ret < 0)
1542                git_die_config(key, NULL);
1543        return ret;
1544}
1545
1546int git_config_get_string(const char *key, char **dest)
1547{
1548        git_config_check_init();
1549        return git_config_get_string_const(key, (const char **)dest);
1550}
1551
1552int git_config_get_int(const char *key, int *dest)
1553{
1554        git_config_check_init();
1555        return git_configset_get_int(&the_config_set, key, dest);
1556}
1557
1558int git_config_get_ulong(const char *key, unsigned long *dest)
1559{
1560        git_config_check_init();
1561        return git_configset_get_ulong(&the_config_set, key, dest);
1562}
1563
1564int git_config_get_bool(const char *key, int *dest)
1565{
1566        git_config_check_init();
1567        return git_configset_get_bool(&the_config_set, key, dest);
1568}
1569
1570int git_config_get_bool_or_int(const char *key, int *is_bool, int *dest)
1571{
1572        git_config_check_init();
1573        return git_configset_get_bool_or_int(&the_config_set, key, is_bool, dest);
1574}
1575
1576int git_config_get_maybe_bool(const char *key, int *dest)
1577{
1578        git_config_check_init();
1579        return git_configset_get_maybe_bool(&the_config_set, key, dest);
1580}
1581
1582int git_config_get_pathname(const char *key, const char **dest)
1583{
1584        int ret;
1585        git_config_check_init();
1586        ret = git_configset_get_pathname(&the_config_set, key, dest);
1587        if (ret < 0)
1588                git_die_config(key, NULL);
1589        return ret;
1590}
1591
1592NORETURN
1593void git_die_config_linenr(const char *key, const char *filename, int linenr)
1594{
1595        if (!filename)
1596                die(_("unable to parse '%s' from command-line config"), key);
1597        else
1598                die(_("bad config variable '%s' in file '%s' at line %d"),
1599                    key, filename, linenr);
1600}
1601
1602NORETURN __attribute__((format(printf, 2, 3)))
1603void git_die_config(const char *key, const char *err, ...)
1604{
1605        const struct string_list *values;
1606        struct key_value_info *kv_info;
1607
1608        if (err) {
1609                va_list params;
1610                va_start(params, err);
1611                vreportf("error: ", err, params);
1612                va_end(params);
1613        }
1614        values = git_config_get_value_multi(key);
1615        kv_info = values->items[values->nr - 1].util;
1616        git_die_config_linenr(key, kv_info->filename, kv_info->linenr);
1617}
1618
1619/*
1620 * Find all the stuff for git_config_set() below.
1621 */
1622
1623static struct {
1624        int baselen;
1625        char *key;
1626        int do_not_match;
1627        regex_t *value_regex;
1628        int multi_replace;
1629        size_t *offset;
1630        unsigned int offset_alloc;
1631        enum { START, SECTION_SEEN, SECTION_END_SEEN, KEY_SEEN } state;
1632        int seen;
1633} store;
1634
1635static int matches(const char *key, const char *value)
1636{
1637        if (strcmp(key, store.key))
1638                return 0; /* not ours */
1639        if (!store.value_regex)
1640                return 1; /* always matches */
1641        if (store.value_regex == CONFIG_REGEX_NONE)
1642                return 0; /* never matches */
1643
1644        return store.do_not_match ^
1645                (value && !regexec(store.value_regex, value, 0, NULL, 0));
1646}
1647
1648static int store_aux(const char *key, const char *value, void *cb)
1649{
1650        const char *ep;
1651        size_t section_len;
1652
1653        switch (store.state) {
1654        case KEY_SEEN:
1655                if (matches(key, value)) {
1656                        if (store.seen == 1 && store.multi_replace == 0) {
1657                                warning(_("%s has multiple values"), key);
1658                        }
1659
1660                        ALLOC_GROW(store.offset, store.seen + 1,
1661                                   store.offset_alloc);
1662
1663                        store.offset[store.seen] = cf->do_ftell(cf);
1664                        store.seen++;
1665                }
1666                break;
1667        case SECTION_SEEN:
1668                /*
1669                 * What we are looking for is in store.key (both
1670                 * section and var), and its section part is baselen
1671                 * long.  We found key (again, both section and var).
1672                 * We would want to know if this key is in the same
1673                 * section as what we are looking for.  We already
1674                 * know we are in the same section as what should
1675                 * hold store.key.
1676                 */
1677                ep = strrchr(key, '.');
1678                section_len = ep - key;
1679
1680                if ((section_len != store.baselen) ||
1681                    memcmp(key, store.key, section_len+1)) {
1682                        store.state = SECTION_END_SEEN;
1683                        break;
1684                }
1685
1686                /*
1687                 * Do not increment matches: this is no match, but we
1688                 * just made sure we are in the desired section.
1689                 */
1690                ALLOC_GROW(store.offset, store.seen + 1,
1691                           store.offset_alloc);
1692                store.offset[store.seen] = cf->do_ftell(cf);
1693                /* fallthru */
1694        case SECTION_END_SEEN:
1695        case START:
1696                if (matches(key, value)) {
1697                        ALLOC_GROW(store.offset, store.seen + 1,
1698                                   store.offset_alloc);
1699                        store.offset[store.seen] = cf->do_ftell(cf);
1700                        store.state = KEY_SEEN;
1701                        store.seen++;
1702                } else {
1703                        if (strrchr(key, '.') - key == store.baselen &&
1704                              !strncmp(key, store.key, store.baselen)) {
1705                                        store.state = SECTION_SEEN;
1706                                        ALLOC_GROW(store.offset,
1707                                                   store.seen + 1,
1708                                                   store.offset_alloc);
1709                                        store.offset[store.seen] = cf->do_ftell(cf);
1710                        }
1711                }
1712        }
1713        return 0;
1714}
1715
1716static int write_error(const char *filename)
1717{
1718        error("failed to write new configuration file %s", filename);
1719
1720        /* Same error code as "failed to rename". */
1721        return 4;
1722}
1723
1724static int store_write_section(int fd, const char *key)
1725{
1726        const char *dot;
1727        int i, success;
1728        struct strbuf sb = STRBUF_INIT;
1729
1730        dot = memchr(key, '.', store.baselen);
1731        if (dot) {
1732                strbuf_addf(&sb, "[%.*s \"", (int)(dot - key), key);
1733                for (i = dot - key + 1; i < store.baselen; i++) {
1734                        if (key[i] == '"' || key[i] == '\\')
1735                                strbuf_addch(&sb, '\\');
1736                        strbuf_addch(&sb, key[i]);
1737                }
1738                strbuf_addstr(&sb, "\"]\n");
1739        } else {
1740                strbuf_addf(&sb, "[%.*s]\n", store.baselen, key);
1741        }
1742
1743        success = write_in_full(fd, sb.buf, sb.len) == sb.len;
1744        strbuf_release(&sb);
1745
1746        return success;
1747}
1748
1749static int store_write_pair(int fd, const char *key, const char *value)
1750{
1751        int i, success;
1752        int length = strlen(key + store.baselen + 1);
1753        const char *quote = "";
1754        struct strbuf sb = STRBUF_INIT;
1755
1756        /*
1757         * Check to see if the value needs to be surrounded with a dq pair.
1758         * Note that problematic characters are always backslash-quoted; this
1759         * check is about not losing leading or trailing SP and strings that
1760         * follow beginning-of-comment characters (i.e. ';' and '#') by the
1761         * configuration parser.
1762         */
1763        if (value[0] == ' ')
1764                quote = "\"";
1765        for (i = 0; value[i]; i++)
1766                if (value[i] == ';' || value[i] == '#')
1767                        quote = "\"";
1768        if (i && value[i - 1] == ' ')
1769                quote = "\"";
1770
1771        strbuf_addf(&sb, "\t%.*s = %s",
1772                    length, key + store.baselen + 1, quote);
1773
1774        for (i = 0; value[i]; i++)
1775                switch (value[i]) {
1776                case '\n':
1777                        strbuf_addstr(&sb, "\\n");
1778                        break;
1779                case '\t':
1780                        strbuf_addstr(&sb, "\\t");
1781                        break;
1782                case '"':
1783                case '\\':
1784                        strbuf_addch(&sb, '\\');
1785                default:
1786                        strbuf_addch(&sb, value[i]);
1787                        break;
1788                }
1789        strbuf_addf(&sb, "%s\n", quote);
1790
1791        success = write_in_full(fd, sb.buf, sb.len) == sb.len;
1792        strbuf_release(&sb);
1793
1794        return success;
1795}
1796
1797static ssize_t find_beginning_of_line(const char *contents, size_t size,
1798        size_t offset_, int *found_bracket)
1799{
1800        size_t equal_offset = size, bracket_offset = size;
1801        ssize_t offset;
1802
1803contline:
1804        for (offset = offset_-2; offset > 0
1805                        && contents[offset] != '\n'; offset--)
1806                switch (contents[offset]) {
1807                        case '=': equal_offset = offset; break;
1808                        case ']': bracket_offset = offset; break;
1809                }
1810        if (offset > 0 && contents[offset-1] == '\\') {
1811                offset_ = offset;
1812                goto contline;
1813        }
1814        if (bracket_offset < equal_offset) {
1815                *found_bracket = 1;
1816                offset = bracket_offset+1;
1817        } else
1818                offset++;
1819
1820        return offset;
1821}
1822
1823int git_config_set_in_file(const char *config_filename,
1824                        const char *key, const char *value)
1825{
1826        return git_config_set_multivar_in_file(config_filename, key, value, NULL, 0);
1827}
1828
1829int git_config_set(const char *key, const char *value)
1830{
1831        return git_config_set_multivar(key, value, NULL, 0);
1832}
1833
1834/*
1835 * Auxiliary function to sanity-check and split the key into the section
1836 * identifier and variable name.
1837 *
1838 * Returns 0 on success, -1 when there is an invalid character in the key and
1839 * -2 if there is no section name in the key.
1840 *
1841 * store_key - pointer to char* which will hold a copy of the key with
1842 *             lowercase section and variable name
1843 * baselen - pointer to int which will hold the length of the
1844 *           section + subsection part, can be NULL
1845 */
1846int git_config_parse_key(const char *key, char **store_key, int *baselen_)
1847{
1848        int i, dot, baselen;
1849        const char *last_dot = strrchr(key, '.');
1850
1851        /*
1852         * Since "key" actually contains the section name and the real
1853         * key name separated by a dot, we have to know where the dot is.
1854         */
1855
1856        if (last_dot == NULL || last_dot == key) {
1857                error("key does not contain a section: %s", key);
1858                return -CONFIG_NO_SECTION_OR_NAME;
1859        }
1860
1861        if (!last_dot[1]) {
1862                error("key does not contain variable name: %s", key);
1863                return -CONFIG_NO_SECTION_OR_NAME;
1864        }
1865
1866        baselen = last_dot - key;
1867        if (baselen_)
1868                *baselen_ = baselen;
1869
1870        /*
1871         * Validate the key and while at it, lower case it for matching.
1872         */
1873        *store_key = xmalloc(strlen(key) + 1);
1874
1875        dot = 0;
1876        for (i = 0; key[i]; i++) {
1877                unsigned char c = key[i];
1878                if (c == '.')
1879                        dot = 1;
1880                /* Leave the extended basename untouched.. */
1881                if (!dot || i > baselen) {
1882                        if (!iskeychar(c) ||
1883                            (i == baselen + 1 && !isalpha(c))) {
1884                                error("invalid key: %s", key);
1885                                goto out_free_ret_1;
1886                        }
1887                        c = tolower(c);
1888                } else if (c == '\n') {
1889                        error("invalid key (newline): %s", key);
1890                        goto out_free_ret_1;
1891                }
1892                (*store_key)[i] = c;
1893        }
1894        (*store_key)[i] = 0;
1895
1896        return 0;
1897
1898out_free_ret_1:
1899        free(*store_key);
1900        *store_key = NULL;
1901        return -CONFIG_INVALID_KEY;
1902}
1903
1904/*
1905 * If value==NULL, unset in (remove from) config,
1906 * if value_regex!=NULL, disregard key/value pairs where value does not match.
1907 * if value_regex==CONFIG_REGEX_NONE, do not match any existing values
1908 *     (only add a new one)
1909 * if multi_replace==0, nothing, or only one matching key/value is replaced,
1910 *     else all matching key/values (regardless how many) are removed,
1911 *     before the new pair is written.
1912 *
1913 * Returns 0 on success.
1914 *
1915 * This function does this:
1916 *
1917 * - it locks the config file by creating ".git/config.lock"
1918 *
1919 * - it then parses the config using store_aux() as validator to find
1920 *   the position on the key/value pair to replace. If it is to be unset,
1921 *   it must be found exactly once.
1922 *
1923 * - the config file is mmap()ed and the part before the match (if any) is
1924 *   written to the lock file, then the changed part and the rest.
1925 *
1926 * - the config file is removed and the lock file rename()d to it.
1927 *
1928 */
1929int git_config_set_multivar_in_file(const char *config_filename,
1930                                const char *key, const char *value,
1931                                const char *value_regex, int multi_replace)
1932{
1933        int fd = -1, in_fd;
1934        int ret;
1935        struct lock_file *lock = NULL;
1936        char *filename_buf = NULL;
1937
1938        /* parse-key returns negative; flip the sign to feed exit(3) */
1939        ret = 0 - git_config_parse_key(key, &store.key, &store.baselen);
1940        if (ret)
1941                goto out_free;
1942
1943        store.multi_replace = multi_replace;
1944
1945        if (!config_filename)
1946                config_filename = filename_buf = git_pathdup("config");
1947
1948        /*
1949         * The lock serves a purpose in addition to locking: the new
1950         * contents of .git/config will be written into it.
1951         */
1952        lock = xcalloc(1, sizeof(struct lock_file));
1953        fd = hold_lock_file_for_update(lock, config_filename, 0);
1954        if (fd < 0) {
1955                error("could not lock config file %s: %s", config_filename, strerror(errno));
1956                free(store.key);
1957                ret = CONFIG_NO_LOCK;
1958                goto out_free;
1959        }
1960
1961        /*
1962         * If .git/config does not exist yet, write a minimal version.
1963         */
1964        in_fd = open(config_filename, O_RDONLY);
1965        if ( in_fd < 0 ) {
1966                free(store.key);
1967
1968                if ( ENOENT != errno ) {
1969                        error("opening %s: %s", config_filename,
1970                              strerror(errno));
1971                        ret = CONFIG_INVALID_FILE; /* same as "invalid config file" */
1972                        goto out_free;
1973                }
1974                /* if nothing to unset, error out */
1975                if (value == NULL) {
1976                        ret = CONFIG_NOTHING_SET;
1977                        goto out_free;
1978                }
1979
1980                store.key = (char *)key;
1981                if (!store_write_section(fd, key) ||
1982                    !store_write_pair(fd, key, value))
1983                        goto write_err_out;
1984        } else {
1985                struct stat st;
1986                char *contents;
1987                size_t contents_sz, copy_begin, copy_end;
1988                int i, new_line = 0;
1989
1990                if (value_regex == NULL)
1991                        store.value_regex = NULL;
1992                else if (value_regex == CONFIG_REGEX_NONE)
1993                        store.value_regex = CONFIG_REGEX_NONE;
1994                else {
1995                        if (value_regex[0] == '!') {
1996                                store.do_not_match = 1;
1997                                value_regex++;
1998                        } else
1999                                store.do_not_match = 0;
2000
2001                        store.value_regex = (regex_t*)xmalloc(sizeof(regex_t));
2002                        if (regcomp(store.value_regex, value_regex,
2003                                        REG_EXTENDED)) {
2004                                error("invalid pattern: %s", value_regex);
2005                                free(store.value_regex);
2006                                ret = CONFIG_INVALID_PATTERN;
2007                                goto out_free;
2008                        }
2009                }
2010
2011                ALLOC_GROW(store.offset, 1, store.offset_alloc);
2012                store.offset[0] = 0;
2013                store.state = START;
2014                store.seen = 0;
2015
2016                /*
2017                 * After this, store.offset will contain the *end* offset
2018                 * of the last match, or remain at 0 if no match was found.
2019                 * As a side effect, we make sure to transform only a valid
2020                 * existing config file.
2021                 */
2022                if (git_config_from_file(store_aux, config_filename, NULL)) {
2023                        error("invalid config file %s", config_filename);
2024                        free(store.key);
2025                        if (store.value_regex != NULL &&
2026                            store.value_regex != CONFIG_REGEX_NONE) {
2027                                regfree(store.value_regex);
2028                                free(store.value_regex);
2029                        }
2030                        ret = CONFIG_INVALID_FILE;
2031                        goto out_free;
2032                }
2033
2034                free(store.key);
2035                if (store.value_regex != NULL &&
2036                    store.value_regex != CONFIG_REGEX_NONE) {
2037                        regfree(store.value_regex);
2038                        free(store.value_regex);
2039                }
2040
2041                /* if nothing to unset, or too many matches, error out */
2042                if ((store.seen == 0 && value == NULL) ||
2043                                (store.seen > 1 && multi_replace == 0)) {
2044                        ret = CONFIG_NOTHING_SET;
2045                        goto out_free;
2046                }
2047
2048                fstat(in_fd, &st);
2049                contents_sz = xsize_t(st.st_size);
2050                contents = xmmap(NULL, contents_sz, PROT_READ,
2051                        MAP_PRIVATE, in_fd, 0);
2052                close(in_fd);
2053
2054                if (chmod(lock->filename.buf, st.st_mode & 07777) < 0) {
2055                        error("chmod on %s failed: %s",
2056                                lock->filename.buf, strerror(errno));
2057                        ret = CONFIG_NO_WRITE;
2058                        goto out_free;
2059                }
2060
2061                if (store.seen == 0)
2062                        store.seen = 1;
2063
2064                for (i = 0, copy_begin = 0; i < store.seen; i++) {
2065                        if (store.offset[i] == 0) {
2066                                store.offset[i] = copy_end = contents_sz;
2067                        } else if (store.state != KEY_SEEN) {
2068                                copy_end = store.offset[i];
2069                        } else
2070                                copy_end = find_beginning_of_line(
2071                                        contents, contents_sz,
2072                                        store.offset[i]-2, &new_line);
2073
2074                        if (copy_end > 0 && contents[copy_end-1] != '\n')
2075                                new_line = 1;
2076
2077                        /* write the first part of the config */
2078                        if (copy_end > copy_begin) {
2079                                if (write_in_full(fd, contents + copy_begin,
2080                                                  copy_end - copy_begin) <
2081                                    copy_end - copy_begin)
2082                                        goto write_err_out;
2083                                if (new_line &&
2084                                    write_str_in_full(fd, "\n") != 1)
2085                                        goto write_err_out;
2086                        }
2087                        copy_begin = store.offset[i];
2088                }
2089
2090                /* write the pair (value == NULL means unset) */
2091                if (value != NULL) {
2092                        if (store.state == START) {
2093                                if (!store_write_section(fd, key))
2094                                        goto write_err_out;
2095                        }
2096                        if (!store_write_pair(fd, key, value))
2097                                goto write_err_out;
2098                }
2099
2100                /* write the rest of the config */
2101                if (copy_begin < contents_sz)
2102                        if (write_in_full(fd, contents + copy_begin,
2103                                          contents_sz - copy_begin) <
2104                            contents_sz - copy_begin)
2105                                goto write_err_out;
2106
2107                munmap(contents, contents_sz);
2108        }
2109
2110        if (commit_lock_file(lock) < 0) {
2111                error("could not commit config file %s", config_filename);
2112                ret = CONFIG_NO_WRITE;
2113                lock = NULL;
2114                goto out_free;
2115        }
2116
2117        /*
2118         * lock is committed, so don't try to roll it back below.
2119         * NOTE: Since lockfile.c keeps a linked list of all created
2120         * lock_file structures, it isn't safe to free(lock).  It's
2121         * better to just leave it hanging around.
2122         */
2123        lock = NULL;
2124        ret = 0;
2125
2126        /* Invalidate the config cache */
2127        git_config_clear();
2128
2129out_free:
2130        if (lock)
2131                rollback_lock_file(lock);
2132        free(filename_buf);
2133        return ret;
2134
2135write_err_out:
2136        ret = write_error(lock->filename.buf);
2137        goto out_free;
2138
2139}
2140
2141int git_config_set_multivar(const char *key, const char *value,
2142                        const char *value_regex, int multi_replace)
2143{
2144        return git_config_set_multivar_in_file(NULL, key, value, value_regex,
2145                                               multi_replace);
2146}
2147
2148static int section_name_match (const char *buf, const char *name)
2149{
2150        int i = 0, j = 0, dot = 0;
2151        if (buf[i] != '[')
2152                return 0;
2153        for (i = 1; buf[i] && buf[i] != ']'; i++) {
2154                if (!dot && isspace(buf[i])) {
2155                        dot = 1;
2156                        if (name[j++] != '.')
2157                                break;
2158                        for (i++; isspace(buf[i]); i++)
2159                                ; /* do nothing */
2160                        if (buf[i] != '"')
2161                                break;
2162                        continue;
2163                }
2164                if (buf[i] == '\\' && dot)
2165                        i++;
2166                else if (buf[i] == '"' && dot) {
2167                        for (i++; isspace(buf[i]); i++)
2168                                ; /* do_nothing */
2169                        break;
2170                }
2171                if (buf[i] != name[j++])
2172                        break;
2173        }
2174        if (buf[i] == ']' && name[j] == 0) {
2175                /*
2176                 * We match, now just find the right length offset by
2177                 * gobbling up any whitespace after it, as well
2178                 */
2179                i++;
2180                for (; buf[i] && isspace(buf[i]); i++)
2181                        ; /* do nothing */
2182                return i;
2183        }
2184        return 0;
2185}
2186
2187static int section_name_is_ok(const char *name)
2188{
2189        /* Empty section names are bogus. */
2190        if (!*name)
2191                return 0;
2192
2193        /*
2194         * Before a dot, we must be alphanumeric or dash. After the first dot,
2195         * anything goes, so we can stop checking.
2196         */
2197        for (; *name && *name != '.'; name++)
2198                if (*name != '-' && !isalnum(*name))
2199                        return 0;
2200        return 1;
2201}
2202
2203/* if new_name == NULL, the section is removed instead */
2204int git_config_rename_section_in_file(const char *config_filename,
2205                                      const char *old_name, const char *new_name)
2206{
2207        int ret = 0, remove = 0;
2208        char *filename_buf = NULL;
2209        struct lock_file *lock;
2210        int out_fd;
2211        char buf[1024];
2212        FILE *config_file;
2213        struct stat st;
2214
2215        if (new_name && !section_name_is_ok(new_name)) {
2216                ret = error("invalid section name: %s", new_name);
2217                goto out;
2218        }
2219
2220        if (!config_filename)
2221                config_filename = filename_buf = git_pathdup("config");
2222
2223        lock = xcalloc(1, sizeof(struct lock_file));
2224        out_fd = hold_lock_file_for_update(lock, config_filename, 0);
2225        if (out_fd < 0) {
2226                ret = error("could not lock config file %s", config_filename);
2227                goto out;
2228        }
2229
2230        if (!(config_file = fopen(config_filename, "rb"))) {
2231                /* no config file means nothing to rename, no error */
2232                goto unlock_and_out;
2233        }
2234
2235        fstat(fileno(config_file), &st);
2236
2237        if (chmod(lock->filename.buf, st.st_mode & 07777) < 0) {
2238                ret = error("chmod on %s failed: %s",
2239                                lock->filename.buf, strerror(errno));
2240                goto out;
2241        }
2242
2243        while (fgets(buf, sizeof(buf), config_file)) {
2244                int i;
2245                int length;
2246                char *output = buf;
2247                for (i = 0; buf[i] && isspace(buf[i]); i++)
2248                        ; /* do nothing */
2249                if (buf[i] == '[') {
2250                        /* it's a section */
2251                        int offset = section_name_match(&buf[i], old_name);
2252                        if (offset > 0) {
2253                                ret++;
2254                                if (new_name == NULL) {
2255                                        remove = 1;
2256                                        continue;
2257                                }
2258                                store.baselen = strlen(new_name);
2259                                if (!store_write_section(out_fd, new_name)) {
2260                                        ret = write_error(lock->filename.buf);
2261                                        goto out;
2262                                }
2263                                /*
2264                                 * We wrote out the new section, with
2265                                 * a newline, now skip the old
2266                                 * section's length
2267                                 */
2268                                output += offset + i;
2269                                if (strlen(output) > 0) {
2270                                        /*
2271                                         * More content means there's
2272                                         * a declaration to put on the
2273                                         * next line; indent with a
2274                                         * tab
2275                                         */
2276                                        output -= 1;
2277                                        output[0] = '\t';
2278                                }
2279                        }
2280                        remove = 0;
2281                }
2282                if (remove)
2283                        continue;
2284                length = strlen(output);
2285                if (write_in_full(out_fd, output, length) != length) {
2286                        ret = write_error(lock->filename.buf);
2287                        goto out;
2288                }
2289        }
2290        fclose(config_file);
2291unlock_and_out:
2292        if (commit_lock_file(lock) < 0)
2293                ret = error("could not commit config file %s", config_filename);
2294out:
2295        free(filename_buf);
2296        return ret;
2297}
2298
2299int git_config_rename_section(const char *old_name, const char *new_name)
2300{
2301        return git_config_rename_section_in_file(NULL, old_name, new_name);
2302}
2303
2304/*
2305 * Call this to report error for your variable that should not
2306 * get a boolean value (i.e. "[my] var" means "true").
2307 */
2308#undef config_error_nonbool
2309int config_error_nonbool(const char *var)
2310{
2311        return error("Missing value for '%s'", var);
2312}
2313
2314int parse_config_key(const char *var,
2315                     const char *section,
2316                     const char **subsection, int *subsection_len,
2317                     const char **key)
2318{
2319        int section_len = strlen(section);
2320        const char *dot;
2321
2322        /* Does it start with "section." ? */
2323        if (!starts_with(var, section) || var[section_len] != '.')
2324                return -1;
2325
2326        /*
2327         * Find the key; we don't know yet if we have a subsection, but we must
2328         * parse backwards from the end, since the subsection may have dots in
2329         * it, too.
2330         */
2331        dot = strrchr(var, '.');
2332        *key = dot + 1;
2333
2334        /* Did we have a subsection at all? */
2335        if (dot == var + section_len) {
2336                *subsection = NULL;
2337                *subsection_len = 0;
2338        }
2339        else {
2340                *subsection = var + section_len + 1;
2341                *subsection_len = dot - *subsection;
2342        }
2343
2344        return 0;
2345}