Andrew's git / gitweb.git / config.c
?
config.con commit Merge branch 'sp/maint-pack-memuse' (948e747)
   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
  11#define MAXNAME (256)
  12
  13static FILE *config_file;
  14static const char *config_file_name;
  15static int config_linenr;
  16static int config_file_eof;
  17static int zlib_compression_seen;
  18
  19const char *config_exclusive_filename = NULL;
  20
  21static int get_next_char(void)
  22{
  23        int c;
  24        FILE *f;
  25
  26        c = '\n';
  27        if ((f = config_file) != NULL) {
  28                c = fgetc(f);
  29                if (c == '\r') {
  30                        /* DOS like systems */
  31                        c = fgetc(f);
  32                        if (c != '\n') {
  33                                ungetc(c, f);
  34                                c = '\r';
  35                        }
  36                }
  37                if (c == '\n')
  38                        config_linenr++;
  39                if (c == EOF) {
  40                        config_file_eof = 1;
  41                        c = '\n';
  42                }
  43        }
  44        return c;
  45}
  46
  47static char *parse_value(void)
  48{
  49        static char value[1024];
  50        int quote = 0, comment = 0, len = 0, space = 0;
  51
  52        for (;;) {
  53                int c = get_next_char();
  54                if (len >= sizeof(value))
  55                        return NULL;
  56                if (c == '\n') {
  57                        if (quote)
  58                                return NULL;
  59                        value[len] = 0;
  60                        return value;
  61                }
  62                if (comment)
  63                        continue;
  64                if (isspace(c) && !quote) {
  65                        space = 1;
  66                        continue;
  67                }
  68                if (!quote) {
  69                        if (c == ';' || c == '#') {
  70                                comment = 1;
  71                                continue;
  72                        }
  73                }
  74                if (space) {
  75                        if (len)
  76                                value[len++] = ' ';
  77                        space = 0;
  78                }
  79                if (c == '\\') {
  80                        c = get_next_char();
  81                        switch (c) {
  82                        case '\n':
  83                                continue;
  84                        case 't':
  85                                c = '\t';
  86                                break;
  87                        case 'b':
  88                                c = '\b';
  89                                break;
  90                        case 'n':
  91                                c = '\n';
  92                                break;
  93                        /* Some characters escape as themselves */
  94                        case '\\': case '"':
  95                                break;
  96                        /* Reject unknown escape sequences */
  97                        default:
  98                                return NULL;
  99                        }
 100                        value[len++] = c;
 101                        continue;
 102                }
 103                if (c == '"') {
 104                        quote = 1-quote;
 105                        continue;
 106                }
 107                value[len++] = c;
 108        }
 109}
 110
 111static inline int iskeychar(int c)
 112{
 113        return isalnum(c) || c == '-';
 114}
 115
 116static int get_value(config_fn_t fn, void *data, char *name, unsigned int len)
 117{
 118        int c;
 119        char *value;
 120
 121        /* Get the full name */
 122        for (;;) {
 123                c = get_next_char();
 124                if (config_file_eof)
 125                        break;
 126                if (!iskeychar(c))
 127                        break;
 128                name[len++] = tolower(c);
 129                if (len >= MAXNAME)
 130                        return -1;
 131        }
 132        name[len] = 0;
 133        while (c == ' ' || c == '\t')
 134                c = get_next_char();
 135
 136        value = NULL;
 137        if (c != '\n') {
 138                if (c != '=')
 139                        return -1;
 140                value = parse_value();
 141                if (!value)
 142                        return -1;
 143        }
 144        return fn(name, value, data);
 145}
 146
 147static int get_extended_base_var(char *name, int baselen, int c)
 148{
 149        do {
 150                if (c == '\n')
 151                        return -1;
 152                c = get_next_char();
 153        } while (isspace(c));
 154
 155        /* We require the format to be '[base "extension"]' */
 156        if (c != '"')
 157                return -1;
 158        name[baselen++] = '.';
 159
 160        for (;;) {
 161                int c = get_next_char();
 162                if (c == '\n')
 163                        return -1;
 164                if (c == '"')
 165                        break;
 166                if (c == '\\') {
 167                        c = get_next_char();
 168                        if (c == '\n')
 169                                return -1;
 170                }
 171                name[baselen++] = c;
 172                if (baselen > MAXNAME / 2)
 173                        return -1;
 174        }
 175
 176        /* Final ']' */
 177        if (get_next_char() != ']')
 178                return -1;
 179        return baselen;
 180}
 181
 182static int get_base_var(char *name)
 183{
 184        int baselen = 0;
 185
 186        for (;;) {
 187                int c = get_next_char();
 188                if (config_file_eof)
 189                        return -1;
 190                if (c == ']')
 191                        return baselen;
 192                if (isspace(c))
 193                        return get_extended_base_var(name, baselen, c);
 194                if (!iskeychar(c) && c != '.')
 195                        return -1;
 196                if (baselen > MAXNAME / 2)
 197                        return -1;
 198                name[baselen++] = tolower(c);
 199        }
 200}
 201
 202static int git_parse_file(config_fn_t fn, void *data)
 203{
 204        int comment = 0;
 205        int baselen = 0;
 206        static char var[MAXNAME];
 207
 208        for (;;) {
 209                int c = get_next_char();
 210                if (c == '\n') {
 211                        if (config_file_eof)
 212                                return 0;
 213                        comment = 0;
 214                        continue;
 215                }
 216                if (comment || isspace(c))
 217                        continue;
 218                if (c == '#' || c == ';') {
 219                        comment = 1;
 220                        continue;
 221                }
 222                if (c == '[') {
 223                        baselen = get_base_var(var);
 224                        if (baselen <= 0)
 225                                break;
 226                        var[baselen++] = '.';
 227                        var[baselen] = 0;
 228                        continue;
 229                }
 230                if (!isalpha(c))
 231                        break;
 232                var[baselen] = tolower(c);
 233                if (get_value(fn, data, var, baselen+1) < 0)
 234                        break;
 235        }
 236        die("bad config file line %d in %s", config_linenr, config_file_name);
 237}
 238
 239static int parse_unit_factor(const char *end, unsigned long *val)
 240{
 241        if (!*end)
 242                return 1;
 243        else if (!strcasecmp(end, "k")) {
 244                *val *= 1024;
 245                return 1;
 246        }
 247        else if (!strcasecmp(end, "m")) {
 248                *val *= 1024 * 1024;
 249                return 1;
 250        }
 251        else if (!strcasecmp(end, "g")) {
 252                *val *= 1024 * 1024 * 1024;
 253                return 1;
 254        }
 255        return 0;
 256}
 257
 258int git_parse_long(const char *value, long *ret)
 259{
 260        if (value && *value) {
 261                char *end;
 262                long val = strtol(value, &end, 0);
 263                unsigned long factor = 1;
 264                if (!parse_unit_factor(end, &factor))
 265                        return 0;
 266                *ret = val * factor;
 267                return 1;
 268        }
 269        return 0;
 270}
 271
 272int git_parse_ulong(const char *value, unsigned long *ret)
 273{
 274        if (value && *value) {
 275                char *end;
 276                unsigned long val = strtoul(value, &end, 0);
 277                if (!parse_unit_factor(end, &val))
 278                        return 0;
 279                *ret = val;
 280                return 1;
 281        }
 282        return 0;
 283}
 284
 285static void die_bad_config(const char *name)
 286{
 287        if (config_file_name)
 288                die("bad config value for '%s' in %s", name, config_file_name);
 289        die("bad config value for '%s'", name);
 290}
 291
 292int git_config_int(const char *name, const char *value)
 293{
 294        long ret;
 295        if (!git_parse_long(value, &ret))
 296                die_bad_config(name);
 297        return ret;
 298}
 299
 300unsigned long git_config_ulong(const char *name, const char *value)
 301{
 302        unsigned long ret;
 303        if (!git_parse_ulong(value, &ret))
 304                die_bad_config(name);
 305        return ret;
 306}
 307
 308int git_config_bool_or_int(const char *name, const char *value, int *is_bool)
 309{
 310        *is_bool = 1;
 311        if (!value)
 312                return 1;
 313        if (!*value)
 314                return 0;
 315        if (!strcasecmp(value, "true") || !strcasecmp(value, "yes"))
 316                return 1;
 317        if (!strcasecmp(value, "false") || !strcasecmp(value, "no"))
 318                return 0;
 319        *is_bool = 0;
 320        return git_config_int(name, value);
 321}
 322
 323int git_config_bool(const char *name, const char *value)
 324{
 325        int discard;
 326        return !!git_config_bool_or_int(name, value, &discard);
 327}
 328
 329int git_config_string(const char **dest, const char *var, const char *value)
 330{
 331        if (!value)
 332                return config_error_nonbool(var);
 333        *dest = xstrdup(value);
 334        return 0;
 335}
 336
 337static int git_default_core_config(const char *var, const char *value)
 338{
 339        /* This needs a better name */
 340        if (!strcmp(var, "core.filemode")) {
 341                trust_executable_bit = git_config_bool(var, value);
 342                return 0;
 343        }
 344
 345        if (!strcmp(var, "core.quotepath")) {
 346                quote_path_fully = git_config_bool(var, value);
 347                return 0;
 348        }
 349
 350        if (!strcmp(var, "core.symlinks")) {
 351                has_symlinks = git_config_bool(var, value);
 352                return 0;
 353        }
 354
 355        if (!strcmp(var, "core.ignorecase")) {
 356                ignore_case = git_config_bool(var, value);
 357                return 0;
 358        }
 359
 360        if (!strcmp(var, "core.bare")) {
 361                is_bare_repository_cfg = git_config_bool(var, value);
 362                return 0;
 363        }
 364
 365        if (!strcmp(var, "core.ignorestat")) {
 366                assume_unchanged = git_config_bool(var, value);
 367                return 0;
 368        }
 369
 370        if (!strcmp(var, "core.prefersymlinkrefs")) {
 371                prefer_symlink_refs = git_config_bool(var, value);
 372                return 0;
 373        }
 374
 375        if (!strcmp(var, "core.logallrefupdates")) {
 376                log_all_ref_updates = git_config_bool(var, value);
 377                return 0;
 378        }
 379
 380        if (!strcmp(var, "core.warnambiguousrefs")) {
 381                warn_ambiguous_refs = git_config_bool(var, value);
 382                return 0;
 383        }
 384
 385        if (!strcmp(var, "core.loosecompression")) {
 386                int level = git_config_int(var, value);
 387                if (level == -1)
 388                        level = Z_DEFAULT_COMPRESSION;
 389                else if (level < 0 || level > Z_BEST_COMPRESSION)
 390                        die("bad zlib compression level %d", level);
 391                zlib_compression_level = level;
 392                zlib_compression_seen = 1;
 393                return 0;
 394        }
 395
 396        if (!strcmp(var, "core.compression")) {
 397                int level = git_config_int(var, value);
 398                if (level == -1)
 399                        level = Z_DEFAULT_COMPRESSION;
 400                else if (level < 0 || level > Z_BEST_COMPRESSION)
 401                        die("bad zlib compression level %d", level);
 402                core_compression_level = level;
 403                core_compression_seen = 1;
 404                if (!zlib_compression_seen)
 405                        zlib_compression_level = level;
 406                return 0;
 407        }
 408
 409        if (!strcmp(var, "core.packedgitwindowsize")) {
 410                int pgsz_x2 = getpagesize() * 2;
 411                packed_git_window_size = git_config_int(var, value);
 412
 413                /* This value must be multiple of (pagesize * 2) */
 414                packed_git_window_size /= pgsz_x2;
 415                if (packed_git_window_size < 1)
 416                        packed_git_window_size = 1;
 417                packed_git_window_size *= pgsz_x2;
 418                return 0;
 419        }
 420
 421        if (!strcmp(var, "core.packedgitlimit")) {
 422                packed_git_limit = git_config_int(var, value);
 423                return 0;
 424        }
 425
 426        if (!strcmp(var, "core.deltabasecachelimit")) {
 427                delta_base_cache_limit = git_config_int(var, value);
 428                return 0;
 429        }
 430
 431        if (!strcmp(var, "core.autocrlf")) {
 432                if (value && !strcasecmp(value, "input")) {
 433                        auto_crlf = -1;
 434                        return 0;
 435                }
 436                auto_crlf = git_config_bool(var, value);
 437                return 0;
 438        }
 439
 440        if (!strcmp(var, "core.safecrlf")) {
 441                if (value && !strcasecmp(value, "warn")) {
 442                        safe_crlf = SAFE_CRLF_WARN;
 443                        return 0;
 444                }
 445                safe_crlf = git_config_bool(var, value);
 446                return 0;
 447        }
 448
 449        if (!strcmp(var, "core.pager"))
 450                return git_config_string(&pager_program, var, value);
 451
 452        if (!strcmp(var, "core.editor"))
 453                return git_config_string(&editor_program, var, value);
 454
 455        if (!strcmp(var, "core.excludesfile"))
 456                return git_config_string(&excludes_file, var, value);
 457
 458        if (!strcmp(var, "core.whitespace")) {
 459                if (!value)
 460                        return config_error_nonbool(var);
 461                whitespace_rule_cfg = parse_whitespace_rule(value);
 462                return 0;
 463        }
 464
 465        if (!strcmp(var, "core.fsyncobjectfiles")) {
 466                fsync_object_files = git_config_bool(var, value);
 467                return 0;
 468        }
 469
 470        /* Add other config variables here and to Documentation/config.txt. */
 471        return 0;
 472}
 473
 474static int git_default_user_config(const char *var, const char *value)
 475{
 476        if (!strcmp(var, "user.name")) {
 477                if (!value)
 478                        return config_error_nonbool(var);
 479                strlcpy(git_default_name, value, sizeof(git_default_name));
 480                if (git_default_email[0])
 481                        user_ident_explicitly_given = 1;
 482                return 0;
 483        }
 484
 485        if (!strcmp(var, "user.email")) {
 486                if (!value)
 487                        return config_error_nonbool(var);
 488                strlcpy(git_default_email, value, sizeof(git_default_email));
 489                if (git_default_name[0])
 490                        user_ident_explicitly_given = 1;
 491                return 0;
 492        }
 493
 494        /* Add other config variables here and to Documentation/config.txt. */
 495        return 0;
 496}
 497
 498static int git_default_i18n_config(const char *var, const char *value)
 499{
 500        if (!strcmp(var, "i18n.commitencoding"))
 501                return git_config_string(&git_commit_encoding, var, value);
 502
 503        if (!strcmp(var, "i18n.logoutputencoding"))
 504                return git_config_string(&git_log_output_encoding, var, value);
 505
 506        /* Add other config variables here and to Documentation/config.txt. */
 507        return 0;
 508}
 509
 510static int git_default_branch_config(const char *var, const char *value)
 511{
 512        if (!strcmp(var, "branch.autosetupmerge")) {
 513                if (value && !strcasecmp(value, "always")) {
 514                        git_branch_track = BRANCH_TRACK_ALWAYS;
 515                        return 0;
 516                }
 517                git_branch_track = git_config_bool(var, value);
 518                return 0;
 519        }
 520        if (!strcmp(var, "branch.autosetuprebase")) {
 521                if (!value)
 522                        return config_error_nonbool(var);
 523                else if (!strcmp(value, "never"))
 524                        autorebase = AUTOREBASE_NEVER;
 525                else if (!strcmp(value, "local"))
 526                        autorebase = AUTOREBASE_LOCAL;
 527                else if (!strcmp(value, "remote"))
 528                        autorebase = AUTOREBASE_REMOTE;
 529                else if (!strcmp(value, "always"))
 530                        autorebase = AUTOREBASE_ALWAYS;
 531                else
 532                        return error("Malformed value for %s", var);
 533                return 0;
 534        }
 535
 536        /* Add other config variables here and to Documentation/config.txt. */
 537        return 0;
 538}
 539
 540int git_default_config(const char *var, const char *value, void *dummy)
 541{
 542        if (!prefixcmp(var, "core."))
 543                return git_default_core_config(var, value);
 544
 545        if (!prefixcmp(var, "user."))
 546                return git_default_user_config(var, value);
 547
 548        if (!prefixcmp(var, "i18n."))
 549                return git_default_i18n_config(var, value);
 550
 551        if (!prefixcmp(var, "branch."))
 552                return git_default_branch_config(var, value);
 553
 554        if (!strcmp(var, "pager.color") || !strcmp(var, "color.pager")) {
 555                pager_use_color = git_config_bool(var,value);
 556                return 0;
 557        }
 558
 559        /* Add other config variables here and to Documentation/config.txt. */
 560        return 0;
 561}
 562
 563int git_config_from_file(config_fn_t fn, const char *filename, void *data)
 564{
 565        int ret;
 566        FILE *f = fopen(filename, "r");
 567
 568        ret = -1;
 569        if (f) {
 570                config_file = f;
 571                config_file_name = filename;
 572                config_linenr = 1;
 573                config_file_eof = 0;
 574                ret = git_parse_file(fn, data);
 575                fclose(f);
 576                config_file_name = NULL;
 577        }
 578        return ret;
 579}
 580
 581const char *git_etc_gitconfig(void)
 582{
 583        static const char *system_wide;
 584        if (!system_wide) {
 585                system_wide = ETC_GITCONFIG;
 586                if (!is_absolute_path(system_wide)) {
 587                        /* interpret path relative to exec-dir */
 588                        struct strbuf d = STRBUF_INIT;
 589                        strbuf_addf(&d, "%s/%s", git_exec_path(), system_wide);
 590                        system_wide = strbuf_detach(&d, NULL);
 591                }
 592        }
 593        return system_wide;
 594}
 595
 596static int git_env_bool(const char *k, int def)
 597{
 598        const char *v = getenv(k);
 599        return v ? git_config_bool(k, v) : def;
 600}
 601
 602int git_config_system(void)
 603{
 604        return !git_env_bool("GIT_CONFIG_NOSYSTEM", 0);
 605}
 606
 607int git_config_global(void)
 608{
 609        return !git_env_bool("GIT_CONFIG_NOGLOBAL", 0);
 610}
 611
 612int git_config(config_fn_t fn, void *data)
 613{
 614        int ret = 0;
 615        char *repo_config = NULL;
 616        const char *home = NULL;
 617
 618        /* $GIT_CONFIG makes git read _only_ the given config file,
 619         * $GIT_CONFIG_LOCAL will make it process it in addition to the
 620         * global config file, the same way it would the per-repository
 621         * config file otherwise. */
 622        if (config_exclusive_filename)
 623                return git_config_from_file(fn, config_exclusive_filename, data);
 624        if (git_config_system() && !access(git_etc_gitconfig(), R_OK))
 625                ret += git_config_from_file(fn, git_etc_gitconfig(),
 626                                            data);
 627
 628        home = getenv("HOME");
 629        if (git_config_global() && home) {
 630                char *user_config = xstrdup(mkpath("%s/.gitconfig", home));
 631                if (!access(user_config, R_OK))
 632                        ret += git_config_from_file(fn, user_config, data);
 633                free(user_config);
 634        }
 635
 636        repo_config = xstrdup(git_path("config"));
 637        ret += git_config_from_file(fn, repo_config, data);
 638        free(repo_config);
 639        return ret;
 640}
 641
 642/*
 643 * Find all the stuff for git_config_set() below.
 644 */
 645
 646#define MAX_MATCHES 512
 647
 648static struct {
 649        int baselen;
 650        char* key;
 651        int do_not_match;
 652        regex_t* value_regex;
 653        int multi_replace;
 654        size_t offset[MAX_MATCHES];
 655        enum { START, SECTION_SEEN, SECTION_END_SEEN, KEY_SEEN } state;
 656        int seen;
 657} store;
 658
 659static int matches(const char* key, const char* value)
 660{
 661        return !strcmp(key, store.key) &&
 662                (store.value_regex == NULL ||
 663                 (store.do_not_match ^
 664                  !regexec(store.value_regex, value, 0, NULL, 0)));
 665}
 666
 667static int store_aux(const char* key, const char* value, void *cb)
 668{
 669        const char *ep;
 670        size_t section_len;
 671
 672        switch (store.state) {
 673        case KEY_SEEN:
 674                if (matches(key, value)) {
 675                        if (store.seen == 1 && store.multi_replace == 0) {
 676                                warning("%s has multiple values", key);
 677                        } else if (store.seen >= MAX_MATCHES) {
 678                                error("too many matches for %s", key);
 679                                return 1;
 680                        }
 681
 682                        store.offset[store.seen] = ftell(config_file);
 683                        store.seen++;
 684                }
 685                break;
 686        case SECTION_SEEN:
 687                /*
 688                 * What we are looking for is in store.key (both
 689                 * section and var), and its section part is baselen
 690                 * long.  We found key (again, both section and var).
 691                 * We would want to know if this key is in the same
 692                 * section as what we are looking for.  We already
 693                 * know we are in the same section as what should
 694                 * hold store.key.
 695                 */
 696                ep = strrchr(key, '.');
 697                section_len = ep - key;
 698
 699                if ((section_len != store.baselen) ||
 700                    memcmp(key, store.key, section_len+1)) {
 701                        store.state = SECTION_END_SEEN;
 702                        break;
 703                }
 704
 705                /*
 706                 * Do not increment matches: this is no match, but we
 707                 * just made sure we are in the desired section.
 708                 */
 709                store.offset[store.seen] = ftell(config_file);
 710                /* fallthru */
 711        case SECTION_END_SEEN:
 712        case START:
 713                if (matches(key, value)) {
 714                        store.offset[store.seen] = ftell(config_file);
 715                        store.state = KEY_SEEN;
 716                        store.seen++;
 717                } else {
 718                        if (strrchr(key, '.') - key == store.baselen &&
 719                              !strncmp(key, store.key, store.baselen)) {
 720                                        store.state = SECTION_SEEN;
 721                                        store.offset[store.seen] = ftell(config_file);
 722                        }
 723                }
 724        }
 725        return 0;
 726}
 727
 728static int write_error(const char *filename)
 729{
 730        error("failed to write new configuration file %s", filename);
 731
 732        /* Same error code as "failed to rename". */
 733        return 4;
 734}
 735
 736static int store_write_section(int fd, const char* key)
 737{
 738        const char *dot;
 739        int i, success;
 740        struct strbuf sb;
 741
 742        strbuf_init(&sb, 0);
 743        dot = memchr(key, '.', store.baselen);
 744        if (dot) {
 745                strbuf_addf(&sb, "[%.*s \"", (int)(dot - key), key);
 746                for (i = dot - key + 1; i < store.baselen; i++) {
 747                        if (key[i] == '"' || key[i] == '\\')
 748                                strbuf_addch(&sb, '\\');
 749                        strbuf_addch(&sb, key[i]);
 750                }
 751                strbuf_addstr(&sb, "\"]\n");
 752        } else {
 753                strbuf_addf(&sb, "[%.*s]\n", store.baselen, key);
 754        }
 755
 756        success = write_in_full(fd, sb.buf, sb.len) == sb.len;
 757        strbuf_release(&sb);
 758
 759        return success;
 760}
 761
 762static int store_write_pair(int fd, const char* key, const char* value)
 763{
 764        int i, success;
 765        int length = strlen(key + store.baselen + 1);
 766        const char *quote = "";
 767        struct strbuf sb;
 768
 769        /*
 770         * Check to see if the value needs to be surrounded with a dq pair.
 771         * Note that problematic characters are always backslash-quoted; this
 772         * check is about not losing leading or trailing SP and strings that
 773         * follow beginning-of-comment characters (i.e. ';' and '#') by the
 774         * configuration parser.
 775         */
 776        if (value[0] == ' ')
 777                quote = "\"";
 778        for (i = 0; value[i]; i++)
 779                if (value[i] == ';' || value[i] == '#')
 780                        quote = "\"";
 781        if (i && value[i - 1] == ' ')
 782                quote = "\"";
 783
 784        strbuf_init(&sb, 0);
 785        strbuf_addf(&sb, "\t%.*s = %s",
 786                    length, key + store.baselen + 1, quote);
 787
 788        for (i = 0; value[i]; i++)
 789                switch (value[i]) {
 790                case '\n':
 791                        strbuf_addstr(&sb, "\\n");
 792                        break;
 793                case '\t':
 794                        strbuf_addstr(&sb, "\\t");
 795                        break;
 796                case '"':
 797                case '\\':
 798                        strbuf_addch(&sb, '\\');
 799                default:
 800                        strbuf_addch(&sb, value[i]);
 801                        break;
 802                }
 803        strbuf_addf(&sb, "%s\n", quote);
 804
 805        success = write_in_full(fd, sb.buf, sb.len) == sb.len;
 806        strbuf_release(&sb);
 807
 808        return success;
 809}
 810
 811static ssize_t find_beginning_of_line(const char* contents, size_t size,
 812        size_t offset_, int* found_bracket)
 813{
 814        size_t equal_offset = size, bracket_offset = size;
 815        ssize_t offset;
 816
 817contline:
 818        for (offset = offset_-2; offset > 0
 819                        && contents[offset] != '\n'; offset--)
 820                switch (contents[offset]) {
 821                        case '=': equal_offset = offset; break;
 822                        case ']': bracket_offset = offset; break;
 823                }
 824        if (offset > 0 && contents[offset-1] == '\\') {
 825                offset_ = offset;
 826                goto contline;
 827        }
 828        if (bracket_offset < equal_offset) {
 829                *found_bracket = 1;
 830                offset = bracket_offset+1;
 831        } else
 832                offset++;
 833
 834        return offset;
 835}
 836
 837int git_config_set(const char* key, const char* value)
 838{
 839        return git_config_set_multivar(key, value, NULL, 0);
 840}
 841
 842/*
 843 * If value==NULL, unset in (remove from) config,
 844 * if value_regex!=NULL, disregard key/value pairs where value does not match.
 845 * if multi_replace==0, nothing, or only one matching key/value is replaced,
 846 *     else all matching key/values (regardless how many) are removed,
 847 *     before the new pair is written.
 848 *
 849 * Returns 0 on success.
 850 *
 851 * This function does this:
 852 *
 853 * - it locks the config file by creating ".git/config.lock"
 854 *
 855 * - it then parses the config using store_aux() as validator to find
 856 *   the position on the key/value pair to replace. If it is to be unset,
 857 *   it must be found exactly once.
 858 *
 859 * - the config file is mmap()ed and the part before the match (if any) is
 860 *   written to the lock file, then the changed part and the rest.
 861 *
 862 * - the config file is removed and the lock file rename()d to it.
 863 *
 864 */
 865int git_config_set_multivar(const char* key, const char* value,
 866        const char* value_regex, int multi_replace)
 867{
 868        int i, dot;
 869        int fd = -1, in_fd;
 870        int ret;
 871        char* config_filename;
 872        struct lock_file *lock = NULL;
 873        const char* last_dot = strrchr(key, '.');
 874
 875        if (config_exclusive_filename)
 876                config_filename = xstrdup(config_exclusive_filename);
 877        else
 878                config_filename = xstrdup(git_path("config"));
 879
 880        /*
 881         * Since "key" actually contains the section name and the real
 882         * key name separated by a dot, we have to know where the dot is.
 883         */
 884
 885        if (last_dot == NULL) {
 886                error("key does not contain a section: %s", key);
 887                ret = 2;
 888                goto out_free;
 889        }
 890        store.baselen = last_dot - key;
 891
 892        store.multi_replace = multi_replace;
 893
 894        /*
 895         * Validate the key and while at it, lower case it for matching.
 896         */
 897        store.key = xmalloc(strlen(key) + 1);
 898        dot = 0;
 899        for (i = 0; key[i]; i++) {
 900                unsigned char c = key[i];
 901                if (c == '.')
 902                        dot = 1;
 903                /* Leave the extended basename untouched.. */
 904                if (!dot || i > store.baselen) {
 905                        if (!iskeychar(c) || (i == store.baselen+1 && !isalpha(c))) {
 906                                error("invalid key: %s", key);
 907                                free(store.key);
 908                                ret = 1;
 909                                goto out_free;
 910                        }
 911                        c = tolower(c);
 912                } else if (c == '\n') {
 913                        error("invalid key (newline): %s", key);
 914                        free(store.key);
 915                        ret = 1;
 916                        goto out_free;
 917                }
 918                store.key[i] = c;
 919        }
 920        store.key[i] = 0;
 921
 922        /*
 923         * The lock serves a purpose in addition to locking: the new
 924         * contents of .git/config will be written into it.
 925         */
 926        lock = xcalloc(sizeof(struct lock_file), 1);
 927        fd = hold_lock_file_for_update(lock, config_filename, 0);
 928        if (fd < 0) {
 929                error("could not lock config file %s", config_filename);
 930                free(store.key);
 931                ret = -1;
 932                goto out_free;
 933        }
 934
 935        /*
 936         * If .git/config does not exist yet, write a minimal version.
 937         */
 938        in_fd = open(config_filename, O_RDONLY);
 939        if ( in_fd < 0 ) {
 940                free(store.key);
 941
 942                if ( ENOENT != errno ) {
 943                        error("opening %s: %s", config_filename,
 944                              strerror(errno));
 945                        ret = 3; /* same as "invalid config file" */
 946                        goto out_free;
 947                }
 948                /* if nothing to unset, error out */
 949                if (value == NULL) {
 950                        ret = 5;
 951                        goto out_free;
 952                }
 953
 954                store.key = (char*)key;
 955                if (!store_write_section(fd, key) ||
 956                    !store_write_pair(fd, key, value))
 957                        goto write_err_out;
 958        } else {
 959                struct stat st;
 960                char* contents;
 961                size_t contents_sz, copy_begin, copy_end;
 962                int i, new_line = 0;
 963
 964                if (value_regex == NULL)
 965                        store.value_regex = NULL;
 966                else {
 967                        if (value_regex[0] == '!') {
 968                                store.do_not_match = 1;
 969                                value_regex++;
 970                        } else
 971                                store.do_not_match = 0;
 972
 973                        store.value_regex = (regex_t*)xmalloc(sizeof(regex_t));
 974                        if (regcomp(store.value_regex, value_regex,
 975                                        REG_EXTENDED)) {
 976                                error("invalid pattern: %s", value_regex);
 977                                free(store.value_regex);
 978                                ret = 6;
 979                                goto out_free;
 980                        }
 981                }
 982
 983                store.offset[0] = 0;
 984                store.state = START;
 985                store.seen = 0;
 986
 987                /*
 988                 * After this, store.offset will contain the *end* offset
 989                 * of the last match, or remain at 0 if no match was found.
 990                 * As a side effect, we make sure to transform only a valid
 991                 * existing config file.
 992                 */
 993                if (git_config_from_file(store_aux, config_filename, NULL)) {
 994                        error("invalid config file %s", config_filename);
 995                        free(store.key);
 996                        if (store.value_regex != NULL) {
 997                                regfree(store.value_regex);
 998                                free(store.value_regex);
 999                        }
1000                        ret = 3;
1001                        goto out_free;
1002                }
1003
1004                free(store.key);
1005                if (store.value_regex != NULL) {
1006                        regfree(store.value_regex);
1007                        free(store.value_regex);
1008                }
1009
1010                /* if nothing to unset, or too many matches, error out */
1011                if ((store.seen == 0 && value == NULL) ||
1012                                (store.seen > 1 && multi_replace == 0)) {
1013                        ret = 5;
1014                        goto out_free;
1015                }
1016
1017                fstat(in_fd, &st);
1018                contents_sz = xsize_t(st.st_size);
1019                contents = xmmap(NULL, contents_sz, PROT_READ,
1020                        MAP_PRIVATE, in_fd, 0);
1021                close(in_fd);
1022
1023                if (store.seen == 0)
1024                        store.seen = 1;
1025
1026                for (i = 0, copy_begin = 0; i < store.seen; i++) {
1027                        if (store.offset[i] == 0) {
1028                                store.offset[i] = copy_end = contents_sz;
1029                        } else if (store.state != KEY_SEEN) {
1030                                copy_end = store.offset[i];
1031                        } else
1032                                copy_end = find_beginning_of_line(
1033                                        contents, contents_sz,
1034                                        store.offset[i]-2, &new_line);
1035
1036                        if (copy_end > 0 && contents[copy_end-1] != '\n')
1037                                new_line = 1;
1038
1039                        /* write the first part of the config */
1040                        if (copy_end > copy_begin) {
1041                                if (write_in_full(fd, contents + copy_begin,
1042                                                  copy_end - copy_begin) <
1043                                    copy_end - copy_begin)
1044                                        goto write_err_out;
1045                                if (new_line &&
1046                                    write_in_full(fd, "\n", 1) != 1)
1047                                        goto write_err_out;
1048                        }
1049                        copy_begin = store.offset[i];
1050                }
1051
1052                /* write the pair (value == NULL means unset) */
1053                if (value != NULL) {
1054                        if (store.state == START) {
1055                                if (!store_write_section(fd, key))
1056                                        goto write_err_out;
1057                        }
1058                        if (!store_write_pair(fd, key, value))
1059                                goto write_err_out;
1060                }
1061
1062                /* write the rest of the config */
1063                if (copy_begin < contents_sz)
1064                        if (write_in_full(fd, contents + copy_begin,
1065                                          contents_sz - copy_begin) <
1066                            contents_sz - copy_begin)
1067                                goto write_err_out;
1068
1069                munmap(contents, contents_sz);
1070        }
1071
1072        if (commit_lock_file(lock) < 0) {
1073                error("could not commit config file %s", config_filename);
1074                ret = 4;
1075                goto out_free;
1076        }
1077
1078        /*
1079         * lock is committed, so don't try to roll it back below.
1080         * NOTE: Since lockfile.c keeps a linked list of all created
1081         * lock_file structures, it isn't safe to free(lock).  It's
1082         * better to just leave it hanging around.
1083         */
1084        lock = NULL;
1085        ret = 0;
1086
1087out_free:
1088        if (lock)
1089                rollback_lock_file(lock);
1090        free(config_filename);
1091        return ret;
1092
1093write_err_out:
1094        ret = write_error(lock->filename);
1095        goto out_free;
1096
1097}
1098
1099static int section_name_match (const char *buf, const char *name)
1100{
1101        int i = 0, j = 0, dot = 0;
1102        for (; buf[i] && buf[i] != ']'; i++) {
1103                if (!dot && isspace(buf[i])) {
1104                        dot = 1;
1105                        if (name[j++] != '.')
1106                                break;
1107                        for (i++; isspace(buf[i]); i++)
1108                                ; /* do nothing */
1109                        if (buf[i] != '"')
1110                                break;
1111                        continue;
1112                }
1113                if (buf[i] == '\\' && dot)
1114                        i++;
1115                else if (buf[i] == '"' && dot) {
1116                        for (i++; isspace(buf[i]); i++)
1117                                ; /* do_nothing */
1118                        break;
1119                }
1120                if (buf[i] != name[j++])
1121                        break;
1122        }
1123        return (buf[i] == ']' && name[j] == 0);
1124}
1125
1126/* if new_name == NULL, the section is removed instead */
1127int git_config_rename_section(const char *old_name, const char *new_name)
1128{
1129        int ret = 0, remove = 0;
1130        char *config_filename;
1131        struct lock_file *lock = xcalloc(sizeof(struct lock_file), 1);
1132        int out_fd;
1133        char buf[1024];
1134
1135        if (config_exclusive_filename)
1136                config_filename = xstrdup(config_exclusive_filename);
1137        else
1138                config_filename = xstrdup(git_path("config"));
1139        out_fd = hold_lock_file_for_update(lock, config_filename, 0);
1140        if (out_fd < 0) {
1141                ret = error("could not lock config file %s", config_filename);
1142                goto out;
1143        }
1144
1145        if (!(config_file = fopen(config_filename, "rb"))) {
1146                /* no config file means nothing to rename, no error */
1147                goto unlock_and_out;
1148        }
1149
1150        while (fgets(buf, sizeof(buf), config_file)) {
1151                int i;
1152                int length;
1153                for (i = 0; buf[i] && isspace(buf[i]); i++)
1154                        ; /* do nothing */
1155                if (buf[i] == '[') {
1156                        /* it's a section */
1157                        if (section_name_match (&buf[i+1], old_name)) {
1158                                ret++;
1159                                if (new_name == NULL) {
1160                                        remove = 1;
1161                                        continue;
1162                                }
1163                                store.baselen = strlen(new_name);
1164                                if (!store_write_section(out_fd, new_name)) {
1165                                        ret = write_error(lock->filename);
1166                                        goto out;
1167                                }
1168                                continue;
1169                        }
1170                        remove = 0;
1171                }
1172                if (remove)
1173                        continue;
1174                length = strlen(buf);
1175                if (write_in_full(out_fd, buf, length) != length) {
1176                        ret = write_error(lock->filename);
1177                        goto out;
1178                }
1179        }
1180        fclose(config_file);
1181 unlock_and_out:
1182        if (commit_lock_file(lock) < 0)
1183                ret = error("could not commit config file %s", config_filename);
1184 out:
1185        free(config_filename);
1186        return ret;
1187}
1188
1189/*
1190 * Call this to report error for your variable that should not
1191 * get a boolean value (i.e. "[my] var" means "true").
1192 */
1193int config_error_nonbool(const char *var)
1194{
1195        return error("Missing value for '%s'", var);
1196}