Andrew's git / gitweb.git / config.c
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config.con commit git-instaweb: pass through invoking user's path to gitweb CGI scripts (3940730)
   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) - 1)
  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                        if (len)
  66                                space++;
  67                        continue;
  68                }
  69                if (!quote) {
  70                        if (c == ';' || c == '#') {
  71                                comment = 1;
  72                                continue;
  73                        }
  74                }
  75                for (; space; space--)
  76                        value[len++] = ' ';
  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, void *data, 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, data);
 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, void *data)
 201{
 202        int comment = 0;
 203        int baselen = 0;
 204        static char var[MAXNAME];
 205
 206        /* U+FEFF Byte Order Mark in UTF8 */
 207        static const unsigned char *utf8_bom = (unsigned char *) "\xef\xbb\xbf";
 208        const unsigned char *bomptr = utf8_bom;
 209
 210        for (;;) {
 211                int c = get_next_char();
 212                if (bomptr && *bomptr) {
 213                        /* We are at the file beginning; skip UTF8-encoded BOM
 214                         * if present. Sane editors won't put this in on their
 215                         * own, but e.g. Windows Notepad will do it happily. */
 216                        if ((unsigned char) c == *bomptr) {
 217                                bomptr++;
 218                                continue;
 219                        } else {
 220                                /* Do not tolerate partial BOM. */
 221                                if (bomptr != utf8_bom)
 222                                        break;
 223                                /* No BOM at file beginning. Cool. */
 224                                bomptr = NULL;
 225                        }
 226                }
 227                if (c == '\n') {
 228                        if (config_file_eof)
 229                                return 0;
 230                        comment = 0;
 231                        continue;
 232                }
 233                if (comment || isspace(c))
 234                        continue;
 235                if (c == '#' || c == ';') {
 236                        comment = 1;
 237                        continue;
 238                }
 239                if (c == '[') {
 240                        baselen = get_base_var(var);
 241                        if (baselen <= 0)
 242                                break;
 243                        var[baselen++] = '.';
 244                        var[baselen] = 0;
 245                        continue;
 246                }
 247                if (!isalpha(c))
 248                        break;
 249                var[baselen] = tolower(c);
 250                if (get_value(fn, data, var, baselen+1) < 0)
 251                        break;
 252        }
 253        die("bad config file line %d in %s", config_linenr, config_file_name);
 254}
 255
 256static int parse_unit_factor(const char *end, unsigned long *val)
 257{
 258        if (!*end)
 259                return 1;
 260        else if (!strcasecmp(end, "k")) {
 261                *val *= 1024;
 262                return 1;
 263        }
 264        else if (!strcasecmp(end, "m")) {
 265                *val *= 1024 * 1024;
 266                return 1;
 267        }
 268        else if (!strcasecmp(end, "g")) {
 269                *val *= 1024 * 1024 * 1024;
 270                return 1;
 271        }
 272        return 0;
 273}
 274
 275static int git_parse_long(const char *value, long *ret)
 276{
 277        if (value && *value) {
 278                char *end;
 279                long val = strtol(value, &end, 0);
 280                unsigned long factor = 1;
 281                if (!parse_unit_factor(end, &factor))
 282                        return 0;
 283                *ret = val * factor;
 284                return 1;
 285        }
 286        return 0;
 287}
 288
 289int git_parse_ulong(const char *value, unsigned long *ret)
 290{
 291        if (value && *value) {
 292                char *end;
 293                unsigned long val = strtoul(value, &end, 0);
 294                if (!parse_unit_factor(end, &val))
 295                        return 0;
 296                *ret = val;
 297                return 1;
 298        }
 299        return 0;
 300}
 301
 302static void die_bad_config(const char *name)
 303{
 304        if (config_file_name)
 305                die("bad config value for '%s' in %s", name, config_file_name);
 306        die("bad config value for '%s'", name);
 307}
 308
 309int git_config_int(const char *name, const char *value)
 310{
 311        long ret = 0;
 312        if (!git_parse_long(value, &ret))
 313                die_bad_config(name);
 314        return ret;
 315}
 316
 317unsigned long git_config_ulong(const char *name, const char *value)
 318{
 319        unsigned long ret;
 320        if (!git_parse_ulong(value, &ret))
 321                die_bad_config(name);
 322        return ret;
 323}
 324
 325int git_config_bool_or_int(const char *name, const char *value, int *is_bool)
 326{
 327        *is_bool = 1;
 328        if (!value)
 329                return 1;
 330        if (!*value)
 331                return 0;
 332        if (!strcasecmp(value, "true") || !strcasecmp(value, "yes") || !strcasecmp(value, "on"))
 333                return 1;
 334        if (!strcasecmp(value, "false") || !strcasecmp(value, "no") || !strcasecmp(value, "off"))
 335                return 0;
 336        *is_bool = 0;
 337        return git_config_int(name, value);
 338}
 339
 340int git_config_bool(const char *name, const char *value)
 341{
 342        int discard;
 343        return !!git_config_bool_or_int(name, value, &discard);
 344}
 345
 346int git_config_string(const char **dest, const char *var, const char *value)
 347{
 348        if (!value)
 349                return config_error_nonbool(var);
 350        *dest = xstrdup(value);
 351        return 0;
 352}
 353
 354int git_config_pathname(const char **dest, const char *var, const char *value)
 355{
 356        if (!value)
 357                return config_error_nonbool(var);
 358        *dest = expand_user_path(value);
 359        if (!*dest)
 360                die("Failed to expand user dir in: '%s'", value);
 361        return 0;
 362}
 363
 364static int git_default_core_config(const char *var, const char *value)
 365{
 366        /* This needs a better name */
 367        if (!strcmp(var, "core.filemode")) {
 368                trust_executable_bit = git_config_bool(var, value);
 369                return 0;
 370        }
 371        if (!strcmp(var, "core.trustctime")) {
 372                trust_ctime = git_config_bool(var, value);
 373                return 0;
 374        }
 375
 376        if (!strcmp(var, "core.quotepath")) {
 377                quote_path_fully = git_config_bool(var, value);
 378                return 0;
 379        }
 380
 381        if (!strcmp(var, "core.symlinks")) {
 382                has_symlinks = git_config_bool(var, value);
 383                return 0;
 384        }
 385
 386        if (!strcmp(var, "core.ignorecase")) {
 387                ignore_case = git_config_bool(var, value);
 388                return 0;
 389        }
 390
 391        if (!strcmp(var, "core.bare")) {
 392                is_bare_repository_cfg = git_config_bool(var, value);
 393                return 0;
 394        }
 395
 396        if (!strcmp(var, "core.ignorestat")) {
 397                assume_unchanged = git_config_bool(var, value);
 398                return 0;
 399        }
 400
 401        if (!strcmp(var, "core.prefersymlinkrefs")) {
 402                prefer_symlink_refs = git_config_bool(var, value);
 403                return 0;
 404        }
 405
 406        if (!strcmp(var, "core.logallrefupdates")) {
 407                log_all_ref_updates = git_config_bool(var, value);
 408                return 0;
 409        }
 410
 411        if (!strcmp(var, "core.warnambiguousrefs")) {
 412                warn_ambiguous_refs = git_config_bool(var, value);
 413                return 0;
 414        }
 415
 416        if (!strcmp(var, "core.loosecompression")) {
 417                int level = git_config_int(var, value);
 418                if (level == -1)
 419                        level = Z_DEFAULT_COMPRESSION;
 420                else if (level < 0 || level > Z_BEST_COMPRESSION)
 421                        die("bad zlib compression level %d", level);
 422                zlib_compression_level = level;
 423                zlib_compression_seen = 1;
 424                return 0;
 425        }
 426
 427        if (!strcmp(var, "core.compression")) {
 428                int level = git_config_int(var, value);
 429                if (level == -1)
 430                        level = Z_DEFAULT_COMPRESSION;
 431                else if (level < 0 || level > Z_BEST_COMPRESSION)
 432                        die("bad zlib compression level %d", level);
 433                core_compression_level = level;
 434                core_compression_seen = 1;
 435                if (!zlib_compression_seen)
 436                        zlib_compression_level = level;
 437                return 0;
 438        }
 439
 440        if (!strcmp(var, "core.packedgitwindowsize")) {
 441                int pgsz_x2 = getpagesize() * 2;
 442                packed_git_window_size = git_config_int(var, value);
 443
 444                /* This value must be multiple of (pagesize * 2) */
 445                packed_git_window_size /= pgsz_x2;
 446                if (packed_git_window_size < 1)
 447                        packed_git_window_size = 1;
 448                packed_git_window_size *= pgsz_x2;
 449                return 0;
 450        }
 451
 452        if (!strcmp(var, "core.packedgitlimit")) {
 453                packed_git_limit = git_config_int(var, value);
 454                return 0;
 455        }
 456
 457        if (!strcmp(var, "core.deltabasecachelimit")) {
 458                delta_base_cache_limit = git_config_int(var, value);
 459                return 0;
 460        }
 461
 462        if (!strcmp(var, "core.autocrlf")) {
 463                if (value && !strcasecmp(value, "input")) {
 464                        auto_crlf = -1;
 465                        return 0;
 466                }
 467                auto_crlf = git_config_bool(var, value);
 468                return 0;
 469        }
 470
 471        if (!strcmp(var, "core.safecrlf")) {
 472                if (value && !strcasecmp(value, "warn")) {
 473                        safe_crlf = SAFE_CRLF_WARN;
 474                        return 0;
 475                }
 476                safe_crlf = git_config_bool(var, value);
 477                return 0;
 478        }
 479
 480        if (!strcmp(var, "core.notesref")) {
 481                notes_ref_name = xstrdup(value);
 482                return 0;
 483        }
 484
 485        if (!strcmp(var, "core.pager"))
 486                return git_config_string(&pager_program, var, value);
 487
 488        if (!strcmp(var, "core.editor"))
 489                return git_config_string(&editor_program, var, value);
 490
 491        if (!strcmp(var, "core.excludesfile"))
 492                return git_config_pathname(&excludes_file, var, value);
 493
 494        if (!strcmp(var, "core.whitespace")) {
 495                if (!value)
 496                        return config_error_nonbool(var);
 497                whitespace_rule_cfg = parse_whitespace_rule(value);
 498                return 0;
 499        }
 500
 501        if (!strcmp(var, "core.fsyncobjectfiles")) {
 502                fsync_object_files = git_config_bool(var, value);
 503                return 0;
 504        }
 505
 506        if (!strcmp(var, "core.preloadindex")) {
 507                core_preload_index = git_config_bool(var, value);
 508                return 0;
 509        }
 510
 511        if (!strcmp(var, "core.createobject")) {
 512                if (!strcmp(value, "rename"))
 513                        object_creation_mode = OBJECT_CREATION_USES_RENAMES;
 514                else if (!strcmp(value, "link"))
 515                        object_creation_mode = OBJECT_CREATION_USES_HARDLINKS;
 516                else
 517                        die("Invalid mode for object creation: %s", value);
 518                return 0;
 519        }
 520
 521        if (!strcmp(var, "core.sparsecheckout")) {
 522                core_apply_sparse_checkout = git_config_bool(var, value);
 523                return 0;
 524        }
 525
 526        /* Add other config variables here and to Documentation/config.txt. */
 527        return 0;
 528}
 529
 530static int git_default_user_config(const char *var, const char *value)
 531{
 532        if (!strcmp(var, "user.name")) {
 533                if (!value)
 534                        return config_error_nonbool(var);
 535                strlcpy(git_default_name, value, sizeof(git_default_name));
 536                user_ident_explicitly_given |= IDENT_NAME_GIVEN;
 537                return 0;
 538        }
 539
 540        if (!strcmp(var, "user.email")) {
 541                if (!value)
 542                        return config_error_nonbool(var);
 543                strlcpy(git_default_email, value, sizeof(git_default_email));
 544                user_ident_explicitly_given |= IDENT_MAIL_GIVEN;
 545                return 0;
 546        }
 547
 548        /* Add other config variables here and to Documentation/config.txt. */
 549        return 0;
 550}
 551
 552static int git_default_i18n_config(const char *var, const char *value)
 553{
 554        if (!strcmp(var, "i18n.commitencoding"))
 555                return git_config_string(&git_commit_encoding, var, value);
 556
 557        if (!strcmp(var, "i18n.logoutputencoding"))
 558                return git_config_string(&git_log_output_encoding, var, value);
 559
 560        /* Add other config variables here and to Documentation/config.txt. */
 561        return 0;
 562}
 563
 564static int git_default_branch_config(const char *var, const char *value)
 565{
 566        if (!strcmp(var, "branch.autosetupmerge")) {
 567                if (value && !strcasecmp(value, "always")) {
 568                        git_branch_track = BRANCH_TRACK_ALWAYS;
 569                        return 0;
 570                }
 571                git_branch_track = git_config_bool(var, value);
 572                return 0;
 573        }
 574        if (!strcmp(var, "branch.autosetuprebase")) {
 575                if (!value)
 576                        return config_error_nonbool(var);
 577                else if (!strcmp(value, "never"))
 578                        autorebase = AUTOREBASE_NEVER;
 579                else if (!strcmp(value, "local"))
 580                        autorebase = AUTOREBASE_LOCAL;
 581                else if (!strcmp(value, "remote"))
 582                        autorebase = AUTOREBASE_REMOTE;
 583                else if (!strcmp(value, "always"))
 584                        autorebase = AUTOREBASE_ALWAYS;
 585                else
 586                        return error("Malformed value for %s", var);
 587                return 0;
 588        }
 589
 590        /* Add other config variables here and to Documentation/config.txt. */
 591        return 0;
 592}
 593
 594static int git_default_push_config(const char *var, const char *value)
 595{
 596        if (!strcmp(var, "push.default")) {
 597                if (!value)
 598                        return config_error_nonbool(var);
 599                else if (!strcmp(value, "nothing"))
 600                        push_default = PUSH_DEFAULT_NOTHING;
 601                else if (!strcmp(value, "matching"))
 602                        push_default = PUSH_DEFAULT_MATCHING;
 603                else if (!strcmp(value, "tracking"))
 604                        push_default = PUSH_DEFAULT_TRACKING;
 605                else if (!strcmp(value, "current"))
 606                        push_default = PUSH_DEFAULT_CURRENT;
 607                else {
 608                        error("Malformed value for %s: %s", var, value);
 609                        return error("Must be one of nothing, matching, "
 610                                     "tracking or current.");
 611                }
 612                return 0;
 613        }
 614
 615        /* Add other config variables here and to Documentation/config.txt. */
 616        return 0;
 617}
 618
 619static int git_default_mailmap_config(const char *var, const char *value)
 620{
 621        if (!strcmp(var, "mailmap.file"))
 622                return git_config_string(&git_mailmap_file, var, value);
 623
 624        /* Add other config variables here and to Documentation/config.txt. */
 625        return 0;
 626}
 627
 628int git_default_config(const char *var, const char *value, void *dummy)
 629{
 630        if (!prefixcmp(var, "core."))
 631                return git_default_core_config(var, value);
 632
 633        if (!prefixcmp(var, "user."))
 634                return git_default_user_config(var, value);
 635
 636        if (!prefixcmp(var, "i18n."))
 637                return git_default_i18n_config(var, value);
 638
 639        if (!prefixcmp(var, "branch."))
 640                return git_default_branch_config(var, value);
 641
 642        if (!prefixcmp(var, "push."))
 643                return git_default_push_config(var, value);
 644
 645        if (!prefixcmp(var, "mailmap."))
 646                return git_default_mailmap_config(var, value);
 647
 648        if (!prefixcmp(var, "advice."))
 649                return git_default_advice_config(var, value);
 650
 651        if (!strcmp(var, "pager.color") || !strcmp(var, "color.pager")) {
 652                pager_use_color = git_config_bool(var,value);
 653                return 0;
 654        }
 655
 656        /* Add other config variables here and to Documentation/config.txt. */
 657        return 0;
 658}
 659
 660int git_config_from_file(config_fn_t fn, const char *filename, void *data)
 661{
 662        int ret;
 663        FILE *f = fopen(filename, "r");
 664
 665        ret = -1;
 666        if (f) {
 667                config_file = f;
 668                config_file_name = filename;
 669                config_linenr = 1;
 670                config_file_eof = 0;
 671                ret = git_parse_file(fn, data);
 672                fclose(f);
 673                config_file_name = NULL;
 674        }
 675        return ret;
 676}
 677
 678const char *git_etc_gitconfig(void)
 679{
 680        static const char *system_wide;
 681        if (!system_wide)
 682                system_wide = system_path(ETC_GITCONFIG);
 683        return system_wide;
 684}
 685
 686static int git_env_bool(const char *k, int def)
 687{
 688        const char *v = getenv(k);
 689        return v ? git_config_bool(k, v) : def;
 690}
 691
 692int git_config_system(void)
 693{
 694        return !git_env_bool("GIT_CONFIG_NOSYSTEM", 0);
 695}
 696
 697int git_config_global(void)
 698{
 699        return !git_env_bool("GIT_CONFIG_NOGLOBAL", 0);
 700}
 701
 702int git_config(config_fn_t fn, void *data)
 703{
 704        int ret = 0, found = 0;
 705        char *repo_config = NULL;
 706        const char *home = NULL;
 707
 708        /* Setting $GIT_CONFIG makes git read _only_ the given config file. */
 709        if (config_exclusive_filename)
 710                return git_config_from_file(fn, config_exclusive_filename, data);
 711        if (git_config_system() && !access(git_etc_gitconfig(), R_OK)) {
 712                ret += git_config_from_file(fn, git_etc_gitconfig(),
 713                                            data);
 714                found += 1;
 715        }
 716
 717        home = getenv("HOME");
 718        if (git_config_global() && home) {
 719                char *user_config = xstrdup(mkpath("%s/.gitconfig", home));
 720                if (!access(user_config, R_OK)) {
 721                        ret += git_config_from_file(fn, user_config, data);
 722                        found += 1;
 723                }
 724                free(user_config);
 725        }
 726
 727        repo_config = git_pathdup("config");
 728        if (!access(repo_config, R_OK)) {
 729                ret += git_config_from_file(fn, repo_config, data);
 730                found += 1;
 731        }
 732        free(repo_config);
 733        if (found == 0)
 734                return -1;
 735        return ret;
 736}
 737
 738/*
 739 * Find all the stuff for git_config_set() below.
 740 */
 741
 742#define MAX_MATCHES 512
 743
 744static struct {
 745        int baselen;
 746        char *key;
 747        int do_not_match;
 748        regex_t *value_regex;
 749        int multi_replace;
 750        size_t offset[MAX_MATCHES];
 751        enum { START, SECTION_SEEN, SECTION_END_SEEN, KEY_SEEN } state;
 752        int seen;
 753} store;
 754
 755static int matches(const char *key, const char *value)
 756{
 757        return !strcmp(key, store.key) &&
 758                (store.value_regex == NULL ||
 759                 (store.do_not_match ^
 760                  !regexec(store.value_regex, value, 0, NULL, 0)));
 761}
 762
 763static int store_aux(const char *key, const char *value, void *cb)
 764{
 765        const char *ep;
 766        size_t section_len;
 767
 768        switch (store.state) {
 769        case KEY_SEEN:
 770                if (matches(key, value)) {
 771                        if (store.seen == 1 && store.multi_replace == 0) {
 772                                warning("%s has multiple values", key);
 773                        } else if (store.seen >= MAX_MATCHES) {
 774                                error("too many matches for %s", key);
 775                                return 1;
 776                        }
 777
 778                        store.offset[store.seen] = ftell(config_file);
 779                        store.seen++;
 780                }
 781                break;
 782        case SECTION_SEEN:
 783                /*
 784                 * What we are looking for is in store.key (both
 785                 * section and var), and its section part is baselen
 786                 * long.  We found key (again, both section and var).
 787                 * We would want to know if this key is in the same
 788                 * section as what we are looking for.  We already
 789                 * know we are in the same section as what should
 790                 * hold store.key.
 791                 */
 792                ep = strrchr(key, '.');
 793                section_len = ep - key;
 794
 795                if ((section_len != store.baselen) ||
 796                    memcmp(key, store.key, section_len+1)) {
 797                        store.state = SECTION_END_SEEN;
 798                        break;
 799                }
 800
 801                /*
 802                 * Do not increment matches: this is no match, but we
 803                 * just made sure we are in the desired section.
 804                 */
 805                store.offset[store.seen] = ftell(config_file);
 806                /* fallthru */
 807        case SECTION_END_SEEN:
 808        case START:
 809                if (matches(key, value)) {
 810                        store.offset[store.seen] = ftell(config_file);
 811                        store.state = KEY_SEEN;
 812                        store.seen++;
 813                } else {
 814                        if (strrchr(key, '.') - key == store.baselen &&
 815                              !strncmp(key, store.key, store.baselen)) {
 816                                        store.state = SECTION_SEEN;
 817                                        store.offset[store.seen] = ftell(config_file);
 818                        }
 819                }
 820        }
 821        return 0;
 822}
 823
 824static int write_error(const char *filename)
 825{
 826        error("failed to write new configuration file %s", filename);
 827
 828        /* Same error code as "failed to rename". */
 829        return 4;
 830}
 831
 832static int store_write_section(int fd, const char *key)
 833{
 834        const char *dot;
 835        int i, success;
 836        struct strbuf sb = STRBUF_INIT;
 837
 838        dot = memchr(key, '.', store.baselen);
 839        if (dot) {
 840                strbuf_addf(&sb, "[%.*s \"", (int)(dot - key), key);
 841                for (i = dot - key + 1; i < store.baselen; i++) {
 842                        if (key[i] == '"' || key[i] == '\\')
 843                                strbuf_addch(&sb, '\\');
 844                        strbuf_addch(&sb, key[i]);
 845                }
 846                strbuf_addstr(&sb, "\"]\n");
 847        } else {
 848                strbuf_addf(&sb, "[%.*s]\n", store.baselen, key);
 849        }
 850
 851        success = write_in_full(fd, sb.buf, sb.len) == sb.len;
 852        strbuf_release(&sb);
 853
 854        return success;
 855}
 856
 857static int store_write_pair(int fd, const char *key, const char *value)
 858{
 859        int i, success;
 860        int length = strlen(key + store.baselen + 1);
 861        const char *quote = "";
 862        struct strbuf sb = STRBUF_INIT;
 863
 864        /*
 865         * Check to see if the value needs to be surrounded with a dq pair.
 866         * Note that problematic characters are always backslash-quoted; this
 867         * check is about not losing leading or trailing SP and strings that
 868         * follow beginning-of-comment characters (i.e. ';' and '#') by the
 869         * configuration parser.
 870         */
 871        if (value[0] == ' ')
 872                quote = "\"";
 873        for (i = 0; value[i]; i++)
 874                if (value[i] == ';' || value[i] == '#')
 875                        quote = "\"";
 876        if (i && value[i - 1] == ' ')
 877                quote = "\"";
 878
 879        strbuf_addf(&sb, "\t%.*s = %s",
 880                    length, key + store.baselen + 1, quote);
 881
 882        for (i = 0; value[i]; i++)
 883                switch (value[i]) {
 884                case '\n':
 885                        strbuf_addstr(&sb, "\\n");
 886                        break;
 887                case '\t':
 888                        strbuf_addstr(&sb, "\\t");
 889                        break;
 890                case '"':
 891                case '\\':
 892                        strbuf_addch(&sb, '\\');
 893                default:
 894                        strbuf_addch(&sb, value[i]);
 895                        break;
 896                }
 897        strbuf_addf(&sb, "%s\n", quote);
 898
 899        success = write_in_full(fd, sb.buf, sb.len) == sb.len;
 900        strbuf_release(&sb);
 901
 902        return success;
 903}
 904
 905static ssize_t find_beginning_of_line(const char *contents, size_t size,
 906        size_t offset_, int *found_bracket)
 907{
 908        size_t equal_offset = size, bracket_offset = size;
 909        ssize_t offset;
 910
 911contline:
 912        for (offset = offset_-2; offset > 0
 913                        && contents[offset] != '\n'; offset--)
 914                switch (contents[offset]) {
 915                        case '=': equal_offset = offset; break;
 916                        case ']': bracket_offset = offset; break;
 917                }
 918        if (offset > 0 && contents[offset-1] == '\\') {
 919                offset_ = offset;
 920                goto contline;
 921        }
 922        if (bracket_offset < equal_offset) {
 923                *found_bracket = 1;
 924                offset = bracket_offset+1;
 925        } else
 926                offset++;
 927
 928        return offset;
 929}
 930
 931int git_config_set(const char *key, const char *value)
 932{
 933        return git_config_set_multivar(key, value, NULL, 0);
 934}
 935
 936/*
 937 * If value==NULL, unset in (remove from) config,
 938 * if value_regex!=NULL, disregard key/value pairs where value does not match.
 939 * if multi_replace==0, nothing, or only one matching key/value is replaced,
 940 *     else all matching key/values (regardless how many) are removed,
 941 *     before the new pair is written.
 942 *
 943 * Returns 0 on success.
 944 *
 945 * This function does this:
 946 *
 947 * - it locks the config file by creating ".git/config.lock"
 948 *
 949 * - it then parses the config using store_aux() as validator to find
 950 *   the position on the key/value pair to replace. If it is to be unset,
 951 *   it must be found exactly once.
 952 *
 953 * - the config file is mmap()ed and the part before the match (if any) is
 954 *   written to the lock file, then the changed part and the rest.
 955 *
 956 * - the config file is removed and the lock file rename()d to it.
 957 *
 958 */
 959int git_config_set_multivar(const char *key, const char *value,
 960        const char *value_regex, int multi_replace)
 961{
 962        int i, dot;
 963        int fd = -1, in_fd;
 964        int ret;
 965        char *config_filename;
 966        struct lock_file *lock = NULL;
 967        const char *last_dot = strrchr(key, '.');
 968
 969        if (config_exclusive_filename)
 970                config_filename = xstrdup(config_exclusive_filename);
 971        else
 972                config_filename = git_pathdup("config");
 973
 974        /*
 975         * Since "key" actually contains the section name and the real
 976         * key name separated by a dot, we have to know where the dot is.
 977         */
 978
 979        if (last_dot == NULL) {
 980                error("key does not contain a section: %s", key);
 981                ret = 2;
 982                goto out_free;
 983        }
 984        store.baselen = last_dot - key;
 985
 986        store.multi_replace = multi_replace;
 987
 988        /*
 989         * Validate the key and while at it, lower case it for matching.
 990         */
 991        store.key = xmalloc(strlen(key) + 1);
 992        dot = 0;
 993        for (i = 0; key[i]; i++) {
 994                unsigned char c = key[i];
 995                if (c == '.')
 996                        dot = 1;
 997                /* Leave the extended basename untouched.. */
 998                if (!dot || i > store.baselen) {
 999                        if (!iskeychar(c) || (i == store.baselen+1 && !isalpha(c))) {
1000                                error("invalid key: %s", key);
1001                                free(store.key);
1002                                ret = 1;
1003                                goto out_free;
1004                        }
1005                        c = tolower(c);
1006                } else if (c == '\n') {
1007                        error("invalid key (newline): %s", key);
1008                        free(store.key);
1009                        ret = 1;
1010                        goto out_free;
1011                }
1012                store.key[i] = c;
1013        }
1014        store.key[i] = 0;
1015
1016        /*
1017         * The lock serves a purpose in addition to locking: the new
1018         * contents of .git/config will be written into it.
1019         */
1020        lock = xcalloc(sizeof(struct lock_file), 1);
1021        fd = hold_lock_file_for_update(lock, config_filename, 0);
1022        if (fd < 0) {
1023                error("could not lock config file %s: %s", config_filename, strerror(errno));
1024                free(store.key);
1025                ret = -1;
1026                goto out_free;
1027        }
1028
1029        /*
1030         * If .git/config does not exist yet, write a minimal version.
1031         */
1032        in_fd = open(config_filename, O_RDONLY);
1033        if ( in_fd < 0 ) {
1034                free(store.key);
1035
1036                if ( ENOENT != errno ) {
1037                        error("opening %s: %s", config_filename,
1038                              strerror(errno));
1039                        ret = 3; /* same as "invalid config file" */
1040                        goto out_free;
1041                }
1042                /* if nothing to unset, error out */
1043                if (value == NULL) {
1044                        ret = 5;
1045                        goto out_free;
1046                }
1047
1048                store.key = (char *)key;
1049                if (!store_write_section(fd, key) ||
1050                    !store_write_pair(fd, key, value))
1051                        goto write_err_out;
1052        } else {
1053                struct stat st;
1054                char *contents;
1055                size_t contents_sz, copy_begin, copy_end;
1056                int i, new_line = 0;
1057
1058                if (value_regex == NULL)
1059                        store.value_regex = NULL;
1060                else {
1061                        if (value_regex[0] == '!') {
1062                                store.do_not_match = 1;
1063                                value_regex++;
1064                        } else
1065                                store.do_not_match = 0;
1066
1067                        store.value_regex = (regex_t*)xmalloc(sizeof(regex_t));
1068                        if (regcomp(store.value_regex, value_regex,
1069                                        REG_EXTENDED)) {
1070                                error("invalid pattern: %s", value_regex);
1071                                free(store.value_regex);
1072                                ret = 6;
1073                                goto out_free;
1074                        }
1075                }
1076
1077                store.offset[0] = 0;
1078                store.state = START;
1079                store.seen = 0;
1080
1081                /*
1082                 * After this, store.offset will contain the *end* offset
1083                 * of the last match, or remain at 0 if no match was found.
1084                 * As a side effect, we make sure to transform only a valid
1085                 * existing config file.
1086                 */
1087                if (git_config_from_file(store_aux, config_filename, NULL)) {
1088                        error("invalid config file %s", config_filename);
1089                        free(store.key);
1090                        if (store.value_regex != NULL) {
1091                                regfree(store.value_regex);
1092                                free(store.value_regex);
1093                        }
1094                        ret = 3;
1095                        goto out_free;
1096                }
1097
1098                free(store.key);
1099                if (store.value_regex != NULL) {
1100                        regfree(store.value_regex);
1101                        free(store.value_regex);
1102                }
1103
1104                /* if nothing to unset, or too many matches, error out */
1105                if ((store.seen == 0 && value == NULL) ||
1106                                (store.seen > 1 && multi_replace == 0)) {
1107                        ret = 5;
1108                        goto out_free;
1109                }
1110
1111                fstat(in_fd, &st);
1112                contents_sz = xsize_t(st.st_size);
1113                contents = xmmap(NULL, contents_sz, PROT_READ,
1114                        MAP_PRIVATE, in_fd, 0);
1115                close(in_fd);
1116
1117                if (store.seen == 0)
1118                        store.seen = 1;
1119
1120                for (i = 0, copy_begin = 0; i < store.seen; i++) {
1121                        if (store.offset[i] == 0) {
1122                                store.offset[i] = copy_end = contents_sz;
1123                        } else if (store.state != KEY_SEEN) {
1124                                copy_end = store.offset[i];
1125                        } else
1126                                copy_end = find_beginning_of_line(
1127                                        contents, contents_sz,
1128                                        store.offset[i]-2, &new_line);
1129
1130                        if (copy_end > 0 && contents[copy_end-1] != '\n')
1131                                new_line = 1;
1132
1133                        /* write the first part of the config */
1134                        if (copy_end > copy_begin) {
1135                                if (write_in_full(fd, contents + copy_begin,
1136                                                  copy_end - copy_begin) <
1137                                    copy_end - copy_begin)
1138                                        goto write_err_out;
1139                                if (new_line &&
1140                                    write_str_in_full(fd, "\n") != 1)
1141                                        goto write_err_out;
1142                        }
1143                        copy_begin = store.offset[i];
1144                }
1145
1146                /* write the pair (value == NULL means unset) */
1147                if (value != NULL) {
1148                        if (store.state == START) {
1149                                if (!store_write_section(fd, key))
1150                                        goto write_err_out;
1151                        }
1152                        if (!store_write_pair(fd, key, value))
1153                                goto write_err_out;
1154                }
1155
1156                /* write the rest of the config */
1157                if (copy_begin < contents_sz)
1158                        if (write_in_full(fd, contents + copy_begin,
1159                                          contents_sz - copy_begin) <
1160                            contents_sz - copy_begin)
1161                                goto write_err_out;
1162
1163                munmap(contents, contents_sz);
1164        }
1165
1166        if (commit_lock_file(lock) < 0) {
1167                error("could not commit config file %s", config_filename);
1168                ret = 4;
1169                goto out_free;
1170        }
1171
1172        /*
1173         * lock is committed, so don't try to roll it back below.
1174         * NOTE: Since lockfile.c keeps a linked list of all created
1175         * lock_file structures, it isn't safe to free(lock).  It's
1176         * better to just leave it hanging around.
1177         */
1178        lock = NULL;
1179        ret = 0;
1180
1181out_free:
1182        if (lock)
1183                rollback_lock_file(lock);
1184        free(config_filename);
1185        return ret;
1186
1187write_err_out:
1188        ret = write_error(lock->filename);
1189        goto out_free;
1190
1191}
1192
1193static int section_name_match (const char *buf, const char *name)
1194{
1195        int i = 0, j = 0, dot = 0;
1196        if (buf[i] != '[')
1197                return 0;
1198        for (i = 1; buf[i] && buf[i] != ']'; i++) {
1199                if (!dot && isspace(buf[i])) {
1200                        dot = 1;
1201                        if (name[j++] != '.')
1202                                break;
1203                        for (i++; isspace(buf[i]); i++)
1204                                ; /* do nothing */
1205                        if (buf[i] != '"')
1206                                break;
1207                        continue;
1208                }
1209                if (buf[i] == '\\' && dot)
1210                        i++;
1211                else if (buf[i] == '"' && dot) {
1212                        for (i++; isspace(buf[i]); i++)
1213                                ; /* do_nothing */
1214                        break;
1215                }
1216                if (buf[i] != name[j++])
1217                        break;
1218        }
1219        if (buf[i] == ']' && name[j] == 0) {
1220                /*
1221                 * We match, now just find the right length offset by
1222                 * gobbling up any whitespace after it, as well
1223                 */
1224                i++;
1225                for (; buf[i] && isspace(buf[i]); i++)
1226                        ; /* do nothing */
1227                return i;
1228        }
1229        return 0;
1230}
1231
1232/* if new_name == NULL, the section is removed instead */
1233int git_config_rename_section(const char *old_name, const char *new_name)
1234{
1235        int ret = 0, remove = 0;
1236        char *config_filename;
1237        struct lock_file *lock = xcalloc(sizeof(struct lock_file), 1);
1238        int out_fd;
1239        char buf[1024];
1240
1241        if (config_exclusive_filename)
1242                config_filename = xstrdup(config_exclusive_filename);
1243        else
1244                config_filename = git_pathdup("config");
1245        out_fd = hold_lock_file_for_update(lock, config_filename, 0);
1246        if (out_fd < 0) {
1247                ret = error("could not lock config file %s", config_filename);
1248                goto out;
1249        }
1250
1251        if (!(config_file = fopen(config_filename, "rb"))) {
1252                /* no config file means nothing to rename, no error */
1253                goto unlock_and_out;
1254        }
1255
1256        while (fgets(buf, sizeof(buf), config_file)) {
1257                int i;
1258                int length;
1259                char *output = buf;
1260                for (i = 0; buf[i] && isspace(buf[i]); i++)
1261                        ; /* do nothing */
1262                if (buf[i] == '[') {
1263                        /* it's a section */
1264                        int offset = section_name_match(&buf[i], old_name);
1265                        if (offset > 0) {
1266                                ret++;
1267                                if (new_name == NULL) {
1268                                        remove = 1;
1269                                        continue;
1270                                }
1271                                store.baselen = strlen(new_name);
1272                                if (!store_write_section(out_fd, new_name)) {
1273                                        ret = write_error(lock->filename);
1274                                        goto out;
1275                                }
1276                                /*
1277                                 * We wrote out the new section, with
1278                                 * a newline, now skip the old
1279                                 * section's length
1280                                 */
1281                                output += offset + i;
1282                                if (strlen(output) > 0) {
1283                                        /*
1284                                         * More content means there's
1285                                         * a declaration to put on the
1286                                         * next line; indent with a
1287                                         * tab
1288                                         */
1289                                        output -= 1;
1290                                        output[0] = '\t';
1291                                }
1292                        }
1293                        remove = 0;
1294                }
1295                if (remove)
1296                        continue;
1297                length = strlen(output);
1298                if (write_in_full(out_fd, output, length) != length) {
1299                        ret = write_error(lock->filename);
1300                        goto out;
1301                }
1302        }
1303        fclose(config_file);
1304 unlock_and_out:
1305        if (commit_lock_file(lock) < 0)
1306                ret = error("could not commit config file %s", config_filename);
1307 out:
1308        free(config_filename);
1309        return ret;
1310}
1311
1312/*
1313 * Call this to report error for your variable that should not
1314 * get a boolean value (i.e. "[my] var" means "true").
1315 */
1316int config_error_nonbool(const char *var)
1317{
1318        return error("Missing value for '%s'", var);
1319}