Andrew's git / gitweb.git / config.c
?
config.con commit Add 'core.ignorecase' option (0a9b88b)
   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
  19static int get_next_char(void)
  20{
  21        int c;
  22        FILE *f;
  23
  24        c = '\n';
  25        if ((f = config_file) != NULL) {
  26                c = fgetc(f);
  27                if (c == '\r') {
  28                        /* DOS like systems */
  29                        c = fgetc(f);
  30                        if (c != '\n') {
  31                                ungetc(c, f);
  32                                c = '\r';
  33                        }
  34                }
  35                if (c == '\n')
  36                        config_linenr++;
  37                if (c == EOF) {
  38                        config_file_eof = 1;
  39                        c = '\n';
  40                }
  41        }
  42        return c;
  43}
  44
  45static char *parse_value(void)
  46{
  47        static char value[1024];
  48        int quote = 0, comment = 0, len = 0, space = 0;
  49
  50        for (;;) {
  51                int c = get_next_char();
  52                if (len >= sizeof(value))
  53                        return NULL;
  54                if (c == '\n') {
  55                        if (quote)
  56                                return NULL;
  57                        value[len] = 0;
  58                        return value;
  59                }
  60                if (comment)
  61                        continue;
  62                if (isspace(c) && !quote) {
  63                        space = 1;
  64                        continue;
  65                }
  66                if (!quote) {
  67                        if (c == ';' || c == '#') {
  68                                comment = 1;
  69                                continue;
  70                        }
  71                }
  72                if (space) {
  73                        if (len)
  74                                value[len++] = ' ';
  75                        space = 0;
  76                }
  77                if (c == '\\') {
  78                        c = get_next_char();
  79                        switch (c) {
  80                        case '\n':
  81                                continue;
  82                        case 't':
  83                                c = '\t';
  84                                break;
  85                        case 'b':
  86                                c = '\b';
  87                                break;
  88                        case 'n':
  89                                c = '\n';
  90                                break;
  91                        /* Some characters escape as themselves */
  92                        case '\\': case '"':
  93                                break;
  94                        /* Reject unknown escape sequences */
  95                        default:
  96                                return NULL;
  97                        }
  98                        value[len++] = c;
  99                        continue;
 100                }
 101                if (c == '"') {
 102                        quote = 1-quote;
 103                        continue;
 104                }
 105                value[len++] = c;
 106        }
 107}
 108
 109static inline int iskeychar(int c)
 110{
 111        return isalnum(c) || c == '-';
 112}
 113
 114static int get_value(config_fn_t fn, char *name, unsigned int len)
 115{
 116        int c;
 117        char *value;
 118
 119        /* Get the full name */
 120        for (;;) {
 121                c = get_next_char();
 122                if (config_file_eof)
 123                        break;
 124                if (!iskeychar(c))
 125                        break;
 126                name[len++] = tolower(c);
 127                if (len >= MAXNAME)
 128                        return -1;
 129        }
 130        name[len] = 0;
 131        while (c == ' ' || c == '\t')
 132                c = get_next_char();
 133
 134        value = NULL;
 135        if (c != '\n') {
 136                if (c != '=')
 137                        return -1;
 138                value = parse_value();
 139                if (!value)
 140                        return -1;
 141        }
 142        return fn(name, value);
 143}
 144
 145static int get_extended_base_var(char *name, int baselen, int c)
 146{
 147        do {
 148                if (c == '\n')
 149                        return -1;
 150                c = get_next_char();
 151        } while (isspace(c));
 152
 153        /* We require the format to be '[base "extension"]' */
 154        if (c != '"')
 155                return -1;
 156        name[baselen++] = '.';
 157
 158        for (;;) {
 159                int c = get_next_char();
 160                if (c == '\n')
 161                        return -1;
 162                if (c == '"')
 163                        break;
 164                if (c == '\\') {
 165                        c = get_next_char();
 166                        if (c == '\n')
 167                                return -1;
 168                }
 169                name[baselen++] = c;
 170                if (baselen > MAXNAME / 2)
 171                        return -1;
 172        }
 173
 174        /* Final ']' */
 175        if (get_next_char() != ']')
 176                return -1;
 177        return baselen;
 178}
 179
 180static int get_base_var(char *name)
 181{
 182        int baselen = 0;
 183
 184        for (;;) {
 185                int c = get_next_char();
 186                if (config_file_eof)
 187                        return -1;
 188                if (c == ']')
 189                        return baselen;
 190                if (isspace(c))
 191                        return get_extended_base_var(name, baselen, c);
 192                if (!iskeychar(c) && c != '.')
 193                        return -1;
 194                if (baselen > MAXNAME / 2)
 195                        return -1;
 196                name[baselen++] = tolower(c);
 197        }
 198}
 199
 200static int git_parse_file(config_fn_t fn)
 201{
 202        int comment = 0;
 203        int baselen = 0;
 204        static char var[MAXNAME];
 205
 206        for (;;) {
 207                int c = get_next_char();
 208                if (c == '\n') {
 209                        if (config_file_eof)
 210                                return 0;
 211                        comment = 0;
 212                        continue;
 213                }
 214                if (comment || isspace(c))
 215                        continue;
 216                if (c == '#' || c == ';') {
 217                        comment = 1;
 218                        continue;
 219                }
 220                if (c == '[') {
 221                        baselen = get_base_var(var);
 222                        if (baselen <= 0)
 223                                break;
 224                        var[baselen++] = '.';
 225                        var[baselen] = 0;
 226                        continue;
 227                }
 228                if (!isalpha(c))
 229                        break;
 230                var[baselen] = tolower(c);
 231                if (get_value(fn, var, baselen+1) < 0)
 232                        break;
 233        }
 234        die("bad config file line %d in %s", config_linenr, config_file_name);
 235}
 236
 237static int parse_unit_factor(const char *end, unsigned long *val)
 238{
 239        if (!*end)
 240                return 1;
 241        else if (!strcasecmp(end, "k")) {
 242                *val *= 1024;
 243                return 1;
 244        }
 245        else if (!strcasecmp(end, "m")) {
 246                *val *= 1024 * 1024;
 247                return 1;
 248        }
 249        else if (!strcasecmp(end, "g")) {
 250                *val *= 1024 * 1024 * 1024;
 251                return 1;
 252        }
 253        return 0;
 254}
 255
 256int git_parse_long(const char *value, long *ret)
 257{
 258        if (value && *value) {
 259                char *end;
 260                long val = strtol(value, &end, 0);
 261                unsigned long factor = 1;
 262                if (!parse_unit_factor(end, &factor))
 263                        return 0;
 264                *ret = val * factor;
 265                return 1;
 266        }
 267        return 0;
 268}
 269
 270int git_parse_ulong(const char *value, unsigned long *ret)
 271{
 272        if (value && *value) {
 273                char *end;
 274                unsigned long val = strtoul(value, &end, 0);
 275                if (!parse_unit_factor(end, &val))
 276                        return 0;
 277                *ret = val;
 278                return 1;
 279        }
 280        return 0;
 281}
 282
 283static void die_bad_config(const char *name)
 284{
 285        if (config_file_name)
 286                die("bad config value for '%s' in %s", name, config_file_name);
 287        die("bad config value for '%s'", name);
 288}
 289
 290int git_config_int(const char *name, const char *value)
 291{
 292        long ret;
 293        if (!git_parse_long(value, &ret))
 294                die_bad_config(name);
 295        return ret;
 296}
 297
 298unsigned long git_config_ulong(const char *name, const char *value)
 299{
 300        unsigned long ret;
 301        if (!git_parse_ulong(value, &ret))
 302                die_bad_config(name);
 303        return ret;
 304}
 305
 306int git_config_bool(const char *name, const char *value)
 307{
 308        if (!value)
 309                return 1;
 310        if (!*value)
 311                return 0;
 312        if (!strcasecmp(value, "true") || !strcasecmp(value, "yes"))
 313                return 1;
 314        if (!strcasecmp(value, "false") || !strcasecmp(value, "no"))
 315                return 0;
 316        return git_config_int(name, value) != 0;
 317}
 318
 319int git_config_string(const char **dest, const char *var, const char *value)
 320{
 321        if (!value)
 322                return config_error_nonbool(var);
 323        *dest = xstrdup(value);
 324        return 0;
 325}
 326
 327int git_default_config(const char *var, const char *value)
 328{
 329        /* This needs a better name */
 330        if (!strcmp(var, "core.filemode")) {
 331                trust_executable_bit = git_config_bool(var, value);
 332                return 0;
 333        }
 334
 335        if (!strcmp(var, "core.quotepath")) {
 336                quote_path_fully = git_config_bool(var, value);
 337                return 0;
 338        }
 339
 340        if (!strcmp(var, "core.symlinks")) {
 341                has_symlinks = git_config_bool(var, value);
 342                return 0;
 343        }
 344
 345        if (!strcmp(var, "core.ignorecase")) {
 346                ignore_case = git_config_bool(var, value);
 347                return 0;
 348        }
 349
 350        if (!strcmp(var, "core.bare")) {
 351                is_bare_repository_cfg = git_config_bool(var, value);
 352                return 0;
 353        }
 354
 355        if (!strcmp(var, "core.ignorestat")) {
 356                assume_unchanged = git_config_bool(var, value);
 357                return 0;
 358        }
 359
 360        if (!strcmp(var, "core.prefersymlinkrefs")) {
 361                prefer_symlink_refs = git_config_bool(var, value);
 362                return 0;
 363        }
 364
 365        if (!strcmp(var, "core.logallrefupdates")) {
 366                log_all_ref_updates = git_config_bool(var, value);
 367                return 0;
 368        }
 369
 370        if (!strcmp(var, "core.warnambiguousrefs")) {
 371                warn_ambiguous_refs = git_config_bool(var, value);
 372                return 0;
 373        }
 374
 375        if (!strcmp(var, "core.loosecompression")) {
 376                int level = git_config_int(var, value);
 377                if (level == -1)
 378                        level = Z_DEFAULT_COMPRESSION;
 379                else if (level < 0 || level > Z_BEST_COMPRESSION)
 380                        die("bad zlib compression level %d", level);
 381                zlib_compression_level = level;
 382                zlib_compression_seen = 1;
 383                return 0;
 384        }
 385
 386        if (!strcmp(var, "core.compression")) {
 387                int level = git_config_int(var, value);
 388                if (level == -1)
 389                        level = Z_DEFAULT_COMPRESSION;
 390                else if (level < 0 || level > Z_BEST_COMPRESSION)
 391                        die("bad zlib compression level %d", level);
 392                core_compression_level = level;
 393                core_compression_seen = 1;
 394                if (!zlib_compression_seen)
 395                        zlib_compression_level = level;
 396                return 0;
 397        }
 398
 399        if (!strcmp(var, "core.packedgitwindowsize")) {
 400                int pgsz_x2 = getpagesize() * 2;
 401                packed_git_window_size = git_config_int(var, value);
 402
 403                /* This value must be multiple of (pagesize * 2) */
 404                packed_git_window_size /= pgsz_x2;
 405                if (packed_git_window_size < 1)
 406                        packed_git_window_size = 1;
 407                packed_git_window_size *= pgsz_x2;
 408                return 0;
 409        }
 410
 411        if (!strcmp(var, "core.packedgitlimit")) {
 412                packed_git_limit = git_config_int(var, value);
 413                return 0;
 414        }
 415
 416        if (!strcmp(var, "core.deltabasecachelimit")) {
 417                delta_base_cache_limit = git_config_int(var, value);
 418                return 0;
 419        }
 420
 421        if (!strcmp(var, "core.autocrlf")) {
 422                if (value && !strcasecmp(value, "input")) {
 423                        auto_crlf = -1;
 424                        return 0;
 425                }
 426                auto_crlf = git_config_bool(var, value);
 427                return 0;
 428        }
 429
 430        if (!strcmp(var, "core.safecrlf")) {
 431                if (value && !strcasecmp(value, "warn")) {
 432                        safe_crlf = SAFE_CRLF_WARN;
 433                        return 0;
 434                }
 435                safe_crlf = git_config_bool(var, value);
 436                return 0;
 437        }
 438
 439        if (!strcmp(var, "user.name")) {
 440                if (!value)
 441                        return config_error_nonbool(var);
 442                strlcpy(git_default_name, value, sizeof(git_default_name));
 443                return 0;
 444        }
 445
 446        if (!strcmp(var, "user.email")) {
 447                if (!value)
 448                        return config_error_nonbool(var);
 449                strlcpy(git_default_email, value, sizeof(git_default_email));
 450                return 0;
 451        }
 452
 453        if (!strcmp(var, "i18n.commitencoding"))
 454                return git_config_string(&git_commit_encoding, var, value);
 455
 456        if (!strcmp(var, "i18n.logoutputencoding"))
 457                return git_config_string(&git_log_output_encoding, var, value);
 458
 459        if (!strcmp(var, "pager.color") || !strcmp(var, "color.pager")) {
 460                pager_use_color = git_config_bool(var,value);
 461                return 0;
 462        }
 463
 464        if (!strcmp(var, "core.pager"))
 465                return git_config_string(&pager_program, var, value);
 466
 467        if (!strcmp(var, "core.editor"))
 468                return git_config_string(&editor_program, var, value);
 469
 470        if (!strcmp(var, "core.excludesfile"))
 471                return git_config_string(&excludes_file, var, value);
 472
 473        if (!strcmp(var, "core.whitespace")) {
 474                if (!value)
 475                        return config_error_nonbool(var);
 476                whitespace_rule_cfg = parse_whitespace_rule(value);
 477                return 0;
 478        }
 479        if (!strcmp(var, "branch.autosetupmerge")) {
 480                if (value && !strcasecmp(value, "always")) {
 481                        git_branch_track = BRANCH_TRACK_ALWAYS;
 482                        return 0;
 483                }
 484                git_branch_track = git_config_bool(var, value);
 485                return 0;
 486        }
 487
 488        /* Add other config variables here and to Documentation/config.txt. */
 489        return 0;
 490}
 491
 492int git_config_from_file(config_fn_t fn, const char *filename)
 493{
 494        int ret;
 495        FILE *f = fopen(filename, "r");
 496
 497        ret = -1;
 498        if (f) {
 499                config_file = f;
 500                config_file_name = filename;
 501                config_linenr = 1;
 502                config_file_eof = 0;
 503                ret = git_parse_file(fn);
 504                fclose(f);
 505                config_file_name = NULL;
 506        }
 507        return ret;
 508}
 509
 510const char *git_etc_gitconfig(void)
 511{
 512        static const char *system_wide;
 513        if (!system_wide) {
 514                system_wide = ETC_GITCONFIG;
 515                if (!is_absolute_path(system_wide)) {
 516                        /* interpret path relative to exec-dir */
 517                        struct strbuf d = STRBUF_INIT;
 518                        strbuf_addf(&d, "%s/%s", git_exec_path(), system_wide);
 519                        system_wide = strbuf_detach(&d, NULL);
 520                }
 521        }
 522        return system_wide;
 523}
 524
 525int git_env_bool(const char *k, int def)
 526{
 527        const char *v = getenv(k);
 528        return v ? git_config_bool(k, v) : def;
 529}
 530
 531int git_config_system(void)
 532{
 533        return !git_env_bool("GIT_CONFIG_NOSYSTEM", 0);
 534}
 535
 536int git_config_global(void)
 537{
 538        return !git_env_bool("GIT_CONFIG_NOGLOBAL", 0);
 539}
 540
 541int git_config(config_fn_t fn)
 542{
 543        int ret = 0;
 544        char *repo_config = NULL;
 545        const char *home = NULL, *filename;
 546
 547        /* $GIT_CONFIG makes git read _only_ the given config file,
 548         * $GIT_CONFIG_LOCAL will make it process it in addition to the
 549         * global config file, the same way it would the per-repository
 550         * config file otherwise. */
 551        filename = getenv(CONFIG_ENVIRONMENT);
 552        if (!filename) {
 553                if (git_config_system() && !access(git_etc_gitconfig(), R_OK))
 554                        ret += git_config_from_file(fn, git_etc_gitconfig());
 555                home = getenv("HOME");
 556                filename = getenv(CONFIG_LOCAL_ENVIRONMENT);
 557                if (!filename)
 558                        filename = repo_config = xstrdup(git_path("config"));
 559        }
 560
 561        if (git_config_global() && home) {
 562                char *user_config = xstrdup(mkpath("%s/.gitconfig", home));
 563                if (!access(user_config, R_OK))
 564                        ret = git_config_from_file(fn, user_config);
 565                free(user_config);
 566        }
 567
 568        ret += git_config_from_file(fn, filename);
 569        free(repo_config);
 570        return ret;
 571}
 572
 573/*
 574 * Find all the stuff for git_config_set() below.
 575 */
 576
 577#define MAX_MATCHES 512
 578
 579static struct {
 580        int baselen;
 581        char* key;
 582        int do_not_match;
 583        regex_t* value_regex;
 584        int multi_replace;
 585        size_t offset[MAX_MATCHES];
 586        enum { START, SECTION_SEEN, SECTION_END_SEEN, KEY_SEEN } state;
 587        int seen;
 588} store;
 589
 590static int matches(const char* key, const char* value)
 591{
 592        return !strcmp(key, store.key) &&
 593                (store.value_regex == NULL ||
 594                 (store.do_not_match ^
 595                  !regexec(store.value_regex, value, 0, NULL, 0)));
 596}
 597
 598static int store_aux(const char* key, const char* value)
 599{
 600        const char *ep;
 601        size_t section_len;
 602
 603        switch (store.state) {
 604        case KEY_SEEN:
 605                if (matches(key, value)) {
 606                        if (store.seen == 1 && store.multi_replace == 0) {
 607                                fprintf(stderr,
 608                                        "Warning: %s has multiple values\n",
 609                                        key);
 610                        } else if (store.seen >= MAX_MATCHES) {
 611                                fprintf(stderr, "Too many matches\n");
 612                                return 1;
 613                        }
 614
 615                        store.offset[store.seen] = ftell(config_file);
 616                        store.seen++;
 617                }
 618                break;
 619        case SECTION_SEEN:
 620                /*
 621                 * What we are looking for is in store.key (both
 622                 * section and var), and its section part is baselen
 623                 * long.  We found key (again, both section and var).
 624                 * We would want to know if this key is in the same
 625                 * section as what we are looking for.  We already
 626                 * know we are in the same section as what should
 627                 * hold store.key.
 628                 */
 629                ep = strrchr(key, '.');
 630                section_len = ep - key;
 631
 632                if ((section_len != store.baselen) ||
 633                    memcmp(key, store.key, section_len+1)) {
 634                        store.state = SECTION_END_SEEN;
 635                        break;
 636                }
 637
 638                /*
 639                 * Do not increment matches: this is no match, but we
 640                 * just made sure we are in the desired section.
 641                 */
 642                store.offset[store.seen] = ftell(config_file);
 643                /* fallthru */
 644        case SECTION_END_SEEN:
 645        case START:
 646                if (matches(key, value)) {
 647                        store.offset[store.seen] = ftell(config_file);
 648                        store.state = KEY_SEEN;
 649                        store.seen++;
 650                } else {
 651                        if (strrchr(key, '.') - key == store.baselen &&
 652                              !strncmp(key, store.key, store.baselen)) {
 653                                        store.state = SECTION_SEEN;
 654                                        store.offset[store.seen] = ftell(config_file);
 655                        }
 656                }
 657        }
 658        return 0;
 659}
 660
 661static int write_error(void)
 662{
 663        fprintf(stderr, "Failed to write new configuration file\n");
 664
 665        /* Same error code as "failed to rename". */
 666        return 4;
 667}
 668
 669static int store_write_section(int fd, const char* key)
 670{
 671        const char *dot;
 672        int i, success;
 673        struct strbuf sb;
 674
 675        strbuf_init(&sb, 0);
 676        dot = memchr(key, '.', store.baselen);
 677        if (dot) {
 678                strbuf_addf(&sb, "[%.*s \"", (int)(dot - key), key);
 679                for (i = dot - key + 1; i < store.baselen; i++) {
 680                        if (key[i] == '"')
 681                                strbuf_addch(&sb, '\\');
 682                        strbuf_addch(&sb, key[i]);
 683                }
 684                strbuf_addstr(&sb, "\"]\n");
 685        } else {
 686                strbuf_addf(&sb, "[%.*s]\n", store.baselen, key);
 687        }
 688
 689        success = write_in_full(fd, sb.buf, sb.len) == sb.len;
 690        strbuf_release(&sb);
 691
 692        return success;
 693}
 694
 695static int store_write_pair(int fd, const char* key, const char* value)
 696{
 697        int i, success;
 698        int length = strlen(key + store.baselen + 1);
 699        const char *quote = "";
 700        struct strbuf sb;
 701
 702        /*
 703         * Check to see if the value needs to be surrounded with a dq pair.
 704         * Note that problematic characters are always backslash-quoted; this
 705         * check is about not losing leading or trailing SP and strings that
 706         * follow beginning-of-comment characters (i.e. ';' and '#') by the
 707         * configuration parser.
 708         */
 709        if (value[0] == ' ')
 710                quote = "\"";
 711        for (i = 0; value[i]; i++)
 712                if (value[i] == ';' || value[i] == '#')
 713                        quote = "\"";
 714        if (i && value[i - 1] == ' ')
 715                quote = "\"";
 716
 717        strbuf_init(&sb, 0);
 718        strbuf_addf(&sb, "\t%.*s = %s",
 719                    length, key + store.baselen + 1, quote);
 720
 721        for (i = 0; value[i]; i++)
 722                switch (value[i]) {
 723                case '\n':
 724                        strbuf_addstr(&sb, "\\n");
 725                        break;
 726                case '\t':
 727                        strbuf_addstr(&sb, "\\t");
 728                        break;
 729                case '"':
 730                case '\\':
 731                        strbuf_addch(&sb, '\\');
 732                default:
 733                        strbuf_addch(&sb, value[i]);
 734                        break;
 735                }
 736        strbuf_addf(&sb, "%s\n", quote);
 737
 738        success = write_in_full(fd, sb.buf, sb.len) == sb.len;
 739        strbuf_release(&sb);
 740
 741        return success;
 742}
 743
 744static ssize_t find_beginning_of_line(const char* contents, size_t size,
 745        size_t offset_, int* found_bracket)
 746{
 747        size_t equal_offset = size, bracket_offset = size;
 748        ssize_t offset;
 749
 750contline:
 751        for (offset = offset_-2; offset > 0
 752                        && contents[offset] != '\n'; offset--)
 753                switch (contents[offset]) {
 754                        case '=': equal_offset = offset; break;
 755                        case ']': bracket_offset = offset; break;
 756                }
 757        if (offset > 0 && contents[offset-1] == '\\') {
 758                offset_ = offset;
 759                goto contline;
 760        }
 761        if (bracket_offset < equal_offset) {
 762                *found_bracket = 1;
 763                offset = bracket_offset+1;
 764        } else
 765                offset++;
 766
 767        return offset;
 768}
 769
 770int git_config_set(const char* key, const char* value)
 771{
 772        return git_config_set_multivar(key, value, NULL, 0);
 773}
 774
 775/*
 776 * If value==NULL, unset in (remove from) config,
 777 * if value_regex!=NULL, disregard key/value pairs where value does not match.
 778 * if multi_replace==0, nothing, or only one matching key/value is replaced,
 779 *     else all matching key/values (regardless how many) are removed,
 780 *     before the new pair is written.
 781 *
 782 * Returns 0 on success.
 783 *
 784 * This function does this:
 785 *
 786 * - it locks the config file by creating ".git/config.lock"
 787 *
 788 * - it then parses the config using store_aux() as validator to find
 789 *   the position on the key/value pair to replace. If it is to be unset,
 790 *   it must be found exactly once.
 791 *
 792 * - the config file is mmap()ed and the part before the match (if any) is
 793 *   written to the lock file, then the changed part and the rest.
 794 *
 795 * - the config file is removed and the lock file rename()d to it.
 796 *
 797 */
 798int git_config_set_multivar(const char* key, const char* value,
 799        const char* value_regex, int multi_replace)
 800{
 801        int i, dot;
 802        int fd = -1, in_fd;
 803        int ret;
 804        char* config_filename;
 805        struct lock_file *lock = NULL;
 806        const char* last_dot = strrchr(key, '.');
 807
 808        config_filename = getenv(CONFIG_ENVIRONMENT);
 809        if (!config_filename) {
 810                config_filename = getenv(CONFIG_LOCAL_ENVIRONMENT);
 811                if (!config_filename)
 812                        config_filename  = git_path("config");
 813        }
 814        config_filename = xstrdup(config_filename);
 815
 816        /*
 817         * Since "key" actually contains the section name and the real
 818         * key name separated by a dot, we have to know where the dot is.
 819         */
 820
 821        if (last_dot == NULL) {
 822                fprintf(stderr, "key does not contain a section: %s\n", key);
 823                ret = 2;
 824                goto out_free;
 825        }
 826        store.baselen = last_dot - key;
 827
 828        store.multi_replace = multi_replace;
 829
 830        /*
 831         * Validate the key and while at it, lower case it for matching.
 832         */
 833        store.key = xmalloc(strlen(key) + 1);
 834        dot = 0;
 835        for (i = 0; key[i]; i++) {
 836                unsigned char c = key[i];
 837                if (c == '.')
 838                        dot = 1;
 839                /* Leave the extended basename untouched.. */
 840                if (!dot || i > store.baselen) {
 841                        if (!iskeychar(c) || (i == store.baselen+1 && !isalpha(c))) {
 842                                fprintf(stderr, "invalid key: %s\n", key);
 843                                free(store.key);
 844                                ret = 1;
 845                                goto out_free;
 846                        }
 847                        c = tolower(c);
 848                } else if (c == '\n') {
 849                        fprintf(stderr, "invalid key (newline): %s\n", key);
 850                        free(store.key);
 851                        ret = 1;
 852                        goto out_free;
 853                }
 854                store.key[i] = c;
 855        }
 856        store.key[i] = 0;
 857
 858        /*
 859         * The lock serves a purpose in addition to locking: the new
 860         * contents of .git/config will be written into it.
 861         */
 862        lock = xcalloc(sizeof(struct lock_file), 1);
 863        fd = hold_lock_file_for_update(lock, config_filename, 0);
 864        if (fd < 0) {
 865                fprintf(stderr, "could not lock config file\n");
 866                free(store.key);
 867                ret = -1;
 868                goto out_free;
 869        }
 870
 871        /*
 872         * If .git/config does not exist yet, write a minimal version.
 873         */
 874        in_fd = open(config_filename, O_RDONLY);
 875        if ( in_fd < 0 ) {
 876                free(store.key);
 877
 878                if ( ENOENT != errno ) {
 879                        error("opening %s: %s", config_filename,
 880                              strerror(errno));
 881                        ret = 3; /* same as "invalid config file" */
 882                        goto out_free;
 883                }
 884                /* if nothing to unset, error out */
 885                if (value == NULL) {
 886                        ret = 5;
 887                        goto out_free;
 888                }
 889
 890                store.key = (char*)key;
 891                if (!store_write_section(fd, key) ||
 892                    !store_write_pair(fd, key, value))
 893                        goto write_err_out;
 894        } else {
 895                struct stat st;
 896                char* contents;
 897                size_t contents_sz, copy_begin, copy_end;
 898                int i, new_line = 0;
 899
 900                if (value_regex == NULL)
 901                        store.value_regex = NULL;
 902                else {
 903                        if (value_regex[0] == '!') {
 904                                store.do_not_match = 1;
 905                                value_regex++;
 906                        } else
 907                                store.do_not_match = 0;
 908
 909                        store.value_regex = (regex_t*)xmalloc(sizeof(regex_t));
 910                        if (regcomp(store.value_regex, value_regex,
 911                                        REG_EXTENDED)) {
 912                                fprintf(stderr, "Invalid pattern: %s\n",
 913                                        value_regex);
 914                                free(store.value_regex);
 915                                ret = 6;
 916                                goto out_free;
 917                        }
 918                }
 919
 920                store.offset[0] = 0;
 921                store.state = START;
 922                store.seen = 0;
 923
 924                /*
 925                 * After this, store.offset will contain the *end* offset
 926                 * of the last match, or remain at 0 if no match was found.
 927                 * As a side effect, we make sure to transform only a valid
 928                 * existing config file.
 929                 */
 930                if (git_config_from_file(store_aux, config_filename)) {
 931                        fprintf(stderr, "invalid config file\n");
 932                        free(store.key);
 933                        if (store.value_regex != NULL) {
 934                                regfree(store.value_regex);
 935                                free(store.value_regex);
 936                        }
 937                        ret = 3;
 938                        goto out_free;
 939                }
 940
 941                free(store.key);
 942                if (store.value_regex != NULL) {
 943                        regfree(store.value_regex);
 944                        free(store.value_regex);
 945                }
 946
 947                /* if nothing to unset, or too many matches, error out */
 948                if ((store.seen == 0 && value == NULL) ||
 949                                (store.seen > 1 && multi_replace == 0)) {
 950                        ret = 5;
 951                        goto out_free;
 952                }
 953
 954                fstat(in_fd, &st);
 955                contents_sz = xsize_t(st.st_size);
 956                contents = xmmap(NULL, contents_sz, PROT_READ,
 957                        MAP_PRIVATE, in_fd, 0);
 958                close(in_fd);
 959
 960                if (store.seen == 0)
 961                        store.seen = 1;
 962
 963                for (i = 0, copy_begin = 0; i < store.seen; i++) {
 964                        if (store.offset[i] == 0) {
 965                                store.offset[i] = copy_end = contents_sz;
 966                        } else if (store.state != KEY_SEEN) {
 967                                copy_end = store.offset[i];
 968                        } else
 969                                copy_end = find_beginning_of_line(
 970                                        contents, contents_sz,
 971                                        store.offset[i]-2, &new_line);
 972
 973                        if (copy_end > 0 && contents[copy_end-1] != '\n')
 974                                new_line = 1;
 975
 976                        /* write the first part of the config */
 977                        if (copy_end > copy_begin) {
 978                                if (write_in_full(fd, contents + copy_begin,
 979                                                  copy_end - copy_begin) <
 980                                    copy_end - copy_begin)
 981                                        goto write_err_out;
 982                                if (new_line &&
 983                                    write_in_full(fd, "\n", 1) != 1)
 984                                        goto write_err_out;
 985                        }
 986                        copy_begin = store.offset[i];
 987                }
 988
 989                /* write the pair (value == NULL means unset) */
 990                if (value != NULL) {
 991                        if (store.state == START) {
 992                                if (!store_write_section(fd, key))
 993                                        goto write_err_out;
 994                        }
 995                        if (!store_write_pair(fd, key, value))
 996                                goto write_err_out;
 997                }
 998
 999                /* write the rest of the config */
1000                if (copy_begin < contents_sz)
1001                        if (write_in_full(fd, contents + copy_begin,
1002                                          contents_sz - copy_begin) <
1003                            contents_sz - copy_begin)
1004                                goto write_err_out;
1005
1006                munmap(contents, contents_sz);
1007        }
1008
1009        if (commit_lock_file(lock) < 0) {
1010                fprintf(stderr, "Cannot commit config file!\n");
1011                ret = 4;
1012                goto out_free;
1013        }
1014
1015        /*
1016         * lock is committed, so don't try to roll it back below.
1017         * NOTE: Since lockfile.c keeps a linked list of all created
1018         * lock_file structures, it isn't safe to free(lock).  It's
1019         * better to just leave it hanging around.
1020         */
1021        lock = NULL;
1022        ret = 0;
1023
1024out_free:
1025        if (lock)
1026                rollback_lock_file(lock);
1027        free(config_filename);
1028        return ret;
1029
1030write_err_out:
1031        ret = write_error();
1032        goto out_free;
1033
1034}
1035
1036static int section_name_match (const char *buf, const char *name)
1037{
1038        int i = 0, j = 0, dot = 0;
1039        for (; buf[i] && buf[i] != ']'; i++) {
1040                if (!dot && isspace(buf[i])) {
1041                        dot = 1;
1042                        if (name[j++] != '.')
1043                                break;
1044                        for (i++; isspace(buf[i]); i++)
1045                                ; /* do nothing */
1046                        if (buf[i] != '"')
1047                                break;
1048                        continue;
1049                }
1050                if (buf[i] == '\\' && dot)
1051                        i++;
1052                else if (buf[i] == '"' && dot) {
1053                        for (i++; isspace(buf[i]); i++)
1054                                ; /* do_nothing */
1055                        break;
1056                }
1057                if (buf[i] != name[j++])
1058                        break;
1059        }
1060        return (buf[i] == ']' && name[j] == 0);
1061}
1062
1063/* if new_name == NULL, the section is removed instead */
1064int git_config_rename_section(const char *old_name, const char *new_name)
1065{
1066        int ret = 0, remove = 0;
1067        char *config_filename;
1068        struct lock_file *lock = xcalloc(sizeof(struct lock_file), 1);
1069        int out_fd;
1070        char buf[1024];
1071
1072        config_filename = getenv(CONFIG_ENVIRONMENT);
1073        if (!config_filename) {
1074                config_filename = getenv(CONFIG_LOCAL_ENVIRONMENT);
1075                if (!config_filename)
1076                        config_filename  = git_path("config");
1077        }
1078        config_filename = xstrdup(config_filename);
1079        out_fd = hold_lock_file_for_update(lock, config_filename, 0);
1080        if (out_fd < 0) {
1081                ret = error("Could not lock config file!");
1082                goto out;
1083        }
1084
1085        if (!(config_file = fopen(config_filename, "rb"))) {
1086                /* no config file means nothing to rename, no error */
1087                goto unlock_and_out;
1088        }
1089
1090        while (fgets(buf, sizeof(buf), config_file)) {
1091                int i;
1092                int length;
1093                for (i = 0; buf[i] && isspace(buf[i]); i++)
1094                        ; /* do nothing */
1095                if (buf[i] == '[') {
1096                        /* it's a section */
1097                        if (section_name_match (&buf[i+1], old_name)) {
1098                                ret++;
1099                                if (new_name == NULL) {
1100                                        remove = 1;
1101                                        continue;
1102                                }
1103                                store.baselen = strlen(new_name);
1104                                if (!store_write_section(out_fd, new_name)) {
1105                                        ret = write_error();
1106                                        goto out;
1107                                }
1108                                continue;
1109                        }
1110                        remove = 0;
1111                }
1112                if (remove)
1113                        continue;
1114                length = strlen(buf);
1115                if (write_in_full(out_fd, buf, length) != length) {
1116                        ret = write_error();
1117                        goto out;
1118                }
1119        }
1120        fclose(config_file);
1121 unlock_and_out:
1122        if (commit_lock_file(lock) < 0)
1123                        ret = error("Cannot commit config file!");
1124 out:
1125        free(config_filename);
1126        return ret;
1127}
1128
1129/*
1130 * Call this to report error for your variable that should not
1131 * get a boolean value (i.e. "[my] var" means "true").
1132 */
1133int config_error_nonbool(const char *var)
1134{
1135        return error("Missing value for '%s'", var);
1136}