Andrew's git / gitweb.git / config.c
?
config.con commit Allow passing of configuration parameters in the command line (8b1fa77)
   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
  21struct config_item
  22{
  23        struct config_item *next;
  24        char *value;
  25        char name[1 /* NUL */];
  26};
  27static struct config_item *config_parameters;
  28static struct config_item **config_parameters_tail = &config_parameters;
  29
  30static void lowercase(char *p)
  31{
  32        for (; *p; p++)
  33                *p = tolower(*p);
  34}
  35static char *skip_space(const char *p)
  36{
  37        for (; *p; p++)
  38                if (!isspace(*p))
  39                        break;
  40        return (char *)p;
  41}
  42static char *trailing_space(const char *begin, const char *p)
  43{
  44        while (p-- > begin)
  45                if (!isspace(*p))
  46                        break;
  47        return (char *)p + 1;
  48}
  49
  50int git_config_parse_parameter(const char *text)
  51{
  52        struct config_item *ct;
  53        const char *name;
  54        const char *val;
  55        name = skip_space(text);
  56        text = val = strchr(name, '=');
  57        if (!text)
  58                text = name + strlen(name);
  59        text = trailing_space(name, text);
  60        if (text <= name)
  61                return -1;
  62        ct = xcalloc(1, sizeof(struct config_item) + (text - name));
  63        memcpy(ct->name, name, text - name);
  64        lowercase(ct->name);
  65        if (!val)
  66                ct->value = NULL;
  67        else {
  68                val = skip_space(++val /* skip "=" */);
  69                text = trailing_space(val, val + strlen(val));
  70                ct->value = xstrndup(val, text - val);
  71        }
  72        *config_parameters_tail = ct;
  73        config_parameters_tail = &ct->next;
  74        return 0;
  75}
  76
  77static int get_next_char(void)
  78{
  79        int c;
  80        FILE *f;
  81
  82        c = '\n';
  83        if ((f = config_file) != NULL) {
  84                c = fgetc(f);
  85                if (c == '\r') {
  86                        /* DOS like systems */
  87                        c = fgetc(f);
  88                        if (c != '\n') {
  89                                ungetc(c, f);
  90                                c = '\r';
  91                        }
  92                }
  93                if (c == '\n')
  94                        config_linenr++;
  95                if (c == EOF) {
  96                        config_file_eof = 1;
  97                        c = '\n';
  98                }
  99        }
 100        return c;
 101}
 102
 103static char *parse_value(void)
 104{
 105        static char value[1024];
 106        int quote = 0, comment = 0, len = 0, space = 0;
 107
 108        for (;;) {
 109                int c = get_next_char();
 110                if (len >= sizeof(value) - 1)
 111                        return NULL;
 112                if (c == '\n') {
 113                        if (quote)
 114                                return NULL;
 115                        value[len] = 0;
 116                        return value;
 117                }
 118                if (comment)
 119                        continue;
 120                if (isspace(c) && !quote) {
 121                        if (len)
 122                                space++;
 123                        continue;
 124                }
 125                if (!quote) {
 126                        if (c == ';' || c == '#') {
 127                                comment = 1;
 128                                continue;
 129                        }
 130                }
 131                for (; space; space--)
 132                        value[len++] = ' ';
 133                if (c == '\\') {
 134                        c = get_next_char();
 135                        switch (c) {
 136                        case '\n':
 137                                continue;
 138                        case 't':
 139                                c = '\t';
 140                                break;
 141                        case 'b':
 142                                c = '\b';
 143                                break;
 144                        case 'n':
 145                                c = '\n';
 146                                break;
 147                        /* Some characters escape as themselves */
 148                        case '\\': case '"':
 149                                break;
 150                        /* Reject unknown escape sequences */
 151                        default:
 152                                return NULL;
 153                        }
 154                        value[len++] = c;
 155                        continue;
 156                }
 157                if (c == '"') {
 158                        quote = 1-quote;
 159                        continue;
 160                }
 161                value[len++] = c;
 162        }
 163}
 164
 165static inline int iskeychar(int c)
 166{
 167        return isalnum(c) || c == '-';
 168}
 169
 170static int get_value(config_fn_t fn, void *data, char *name, unsigned int len)
 171{
 172        int c;
 173        char *value;
 174
 175        /* Get the full name */
 176        for (;;) {
 177                c = get_next_char();
 178                if (config_file_eof)
 179                        break;
 180                if (!iskeychar(c))
 181                        break;
 182                name[len++] = tolower(c);
 183                if (len >= MAXNAME)
 184                        return -1;
 185        }
 186        name[len] = 0;
 187        while (c == ' ' || c == '\t')
 188                c = get_next_char();
 189
 190        value = NULL;
 191        if (c != '\n') {
 192                if (c != '=')
 193                        return -1;
 194                value = parse_value();
 195                if (!value)
 196                        return -1;
 197        }
 198        return fn(name, value, data);
 199}
 200
 201static int get_extended_base_var(char *name, int baselen, int c)
 202{
 203        do {
 204                if (c == '\n')
 205                        return -1;
 206                c = get_next_char();
 207        } while (isspace(c));
 208
 209        /* We require the format to be '[base "extension"]' */
 210        if (c != '"')
 211                return -1;
 212        name[baselen++] = '.';
 213
 214        for (;;) {
 215                int c = get_next_char();
 216                if (c == '\n')
 217                        return -1;
 218                if (c == '"')
 219                        break;
 220                if (c == '\\') {
 221                        c = get_next_char();
 222                        if (c == '\n')
 223                                return -1;
 224                }
 225                name[baselen++] = c;
 226                if (baselen > MAXNAME / 2)
 227                        return -1;
 228        }
 229
 230        /* Final ']' */
 231        if (get_next_char() != ']')
 232                return -1;
 233        return baselen;
 234}
 235
 236static int get_base_var(char *name)
 237{
 238        int baselen = 0;
 239
 240        for (;;) {
 241                int c = get_next_char();
 242                if (config_file_eof)
 243                        return -1;
 244                if (c == ']')
 245                        return baselen;
 246                if (isspace(c))
 247                        return get_extended_base_var(name, baselen, c);
 248                if (!iskeychar(c) && c != '.')
 249                        return -1;
 250                if (baselen > MAXNAME / 2)
 251                        return -1;
 252                name[baselen++] = tolower(c);
 253        }
 254}
 255
 256static int git_parse_file(config_fn_t fn, void *data)
 257{
 258        int comment = 0;
 259        int baselen = 0;
 260        static char var[MAXNAME];
 261
 262        /* U+FEFF Byte Order Mark in UTF8 */
 263        static const unsigned char *utf8_bom = (unsigned char *) "\xef\xbb\xbf";
 264        const unsigned char *bomptr = utf8_bom;
 265
 266        for (;;) {
 267                int c = get_next_char();
 268                if (bomptr && *bomptr) {
 269                        /* We are at the file beginning; skip UTF8-encoded BOM
 270                         * if present. Sane editors won't put this in on their
 271                         * own, but e.g. Windows Notepad will do it happily. */
 272                        if ((unsigned char) c == *bomptr) {
 273                                bomptr++;
 274                                continue;
 275                        } else {
 276                                /* Do not tolerate partial BOM. */
 277                                if (bomptr != utf8_bom)
 278                                        break;
 279                                /* No BOM at file beginning. Cool. */
 280                                bomptr = NULL;
 281                        }
 282                }
 283                if (c == '\n') {
 284                        if (config_file_eof)
 285                                return 0;
 286                        comment = 0;
 287                        continue;
 288                }
 289                if (comment || isspace(c))
 290                        continue;
 291                if (c == '#' || c == ';') {
 292                        comment = 1;
 293                        continue;
 294                }
 295                if (c == '[') {
 296                        baselen = get_base_var(var);
 297                        if (baselen <= 0)
 298                                break;
 299                        var[baselen++] = '.';
 300                        var[baselen] = 0;
 301                        continue;
 302                }
 303                if (!isalpha(c))
 304                        break;
 305                var[baselen] = tolower(c);
 306                if (get_value(fn, data, var, baselen+1) < 0)
 307                        break;
 308        }
 309        die("bad config file line %d in %s", config_linenr, config_file_name);
 310}
 311
 312static int parse_unit_factor(const char *end, unsigned long *val)
 313{
 314        if (!*end)
 315                return 1;
 316        else if (!strcasecmp(end, "k")) {
 317                *val *= 1024;
 318                return 1;
 319        }
 320        else if (!strcasecmp(end, "m")) {
 321                *val *= 1024 * 1024;
 322                return 1;
 323        }
 324        else if (!strcasecmp(end, "g")) {
 325                *val *= 1024 * 1024 * 1024;
 326                return 1;
 327        }
 328        return 0;
 329}
 330
 331static int git_parse_long(const char *value, long *ret)
 332{
 333        if (value && *value) {
 334                char *end;
 335                long val = strtol(value, &end, 0);
 336                unsigned long factor = 1;
 337                if (!parse_unit_factor(end, &factor))
 338                        return 0;
 339                *ret = val * factor;
 340                return 1;
 341        }
 342        return 0;
 343}
 344
 345int git_parse_ulong(const char *value, unsigned long *ret)
 346{
 347        if (value && *value) {
 348                char *end;
 349                unsigned long val = strtoul(value, &end, 0);
 350                if (!parse_unit_factor(end, &val))
 351                        return 0;
 352                *ret = val;
 353                return 1;
 354        }
 355        return 0;
 356}
 357
 358static void die_bad_config(const char *name)
 359{
 360        if (config_file_name)
 361                die("bad config value for '%s' in %s", name, config_file_name);
 362        die("bad config value for '%s'", name);
 363}
 364
 365int git_config_int(const char *name, const char *value)
 366{
 367        long ret = 0;
 368        if (!git_parse_long(value, &ret))
 369                die_bad_config(name);
 370        return ret;
 371}
 372
 373unsigned long git_config_ulong(const char *name, const char *value)
 374{
 375        unsigned long ret;
 376        if (!git_parse_ulong(value, &ret))
 377                die_bad_config(name);
 378        return ret;
 379}
 380
 381int git_config_bool_or_int(const char *name, const char *value, int *is_bool)
 382{
 383        *is_bool = 1;
 384        if (!value)
 385                return 1;
 386        if (!*value)
 387                return 0;
 388        if (!strcasecmp(value, "true") || !strcasecmp(value, "yes") || !strcasecmp(value, "on"))
 389                return 1;
 390        if (!strcasecmp(value, "false") || !strcasecmp(value, "no") || !strcasecmp(value, "off"))
 391                return 0;
 392        *is_bool = 0;
 393        return git_config_int(name, value);
 394}
 395
 396int git_config_bool(const char *name, const char *value)
 397{
 398        int discard;
 399        return !!git_config_bool_or_int(name, value, &discard);
 400}
 401
 402int git_config_string(const char **dest, const char *var, const char *value)
 403{
 404        if (!value)
 405                return config_error_nonbool(var);
 406        *dest = xstrdup(value);
 407        return 0;
 408}
 409
 410int git_config_pathname(const char **dest, const char *var, const char *value)
 411{
 412        if (!value)
 413                return config_error_nonbool(var);
 414        *dest = expand_user_path(value);
 415        if (!*dest)
 416                die("Failed to expand user dir in: '%s'", value);
 417        return 0;
 418}
 419
 420static int git_default_core_config(const char *var, const char *value)
 421{
 422        /* This needs a better name */
 423        if (!strcmp(var, "core.filemode")) {
 424                trust_executable_bit = git_config_bool(var, value);
 425                return 0;
 426        }
 427        if (!strcmp(var, "core.trustctime")) {
 428                trust_ctime = git_config_bool(var, value);
 429                return 0;
 430        }
 431
 432        if (!strcmp(var, "core.quotepath")) {
 433                quote_path_fully = git_config_bool(var, value);
 434                return 0;
 435        }
 436
 437        if (!strcmp(var, "core.symlinks")) {
 438                has_symlinks = git_config_bool(var, value);
 439                return 0;
 440        }
 441
 442        if (!strcmp(var, "core.ignorecase")) {
 443                ignore_case = git_config_bool(var, value);
 444                return 0;
 445        }
 446
 447        if (!strcmp(var, "core.bare")) {
 448                is_bare_repository_cfg = git_config_bool(var, value);
 449                return 0;
 450        }
 451
 452        if (!strcmp(var, "core.ignorestat")) {
 453                assume_unchanged = git_config_bool(var, value);
 454                return 0;
 455        }
 456
 457        if (!strcmp(var, "core.prefersymlinkrefs")) {
 458                prefer_symlink_refs = git_config_bool(var, value);
 459                return 0;
 460        }
 461
 462        if (!strcmp(var, "core.logallrefupdates")) {
 463                log_all_ref_updates = git_config_bool(var, value);
 464                return 0;
 465        }
 466
 467        if (!strcmp(var, "core.warnambiguousrefs")) {
 468                warn_ambiguous_refs = git_config_bool(var, value);
 469                return 0;
 470        }
 471
 472        if (!strcmp(var, "core.loosecompression")) {
 473                int level = git_config_int(var, value);
 474                if (level == -1)
 475                        level = Z_DEFAULT_COMPRESSION;
 476                else if (level < 0 || level > Z_BEST_COMPRESSION)
 477                        die("bad zlib compression level %d", level);
 478                zlib_compression_level = level;
 479                zlib_compression_seen = 1;
 480                return 0;
 481        }
 482
 483        if (!strcmp(var, "core.compression")) {
 484                int level = git_config_int(var, value);
 485                if (level == -1)
 486                        level = Z_DEFAULT_COMPRESSION;
 487                else if (level < 0 || level > Z_BEST_COMPRESSION)
 488                        die("bad zlib compression level %d", level);
 489                core_compression_level = level;
 490                core_compression_seen = 1;
 491                if (!zlib_compression_seen)
 492                        zlib_compression_level = level;
 493                return 0;
 494        }
 495
 496        if (!strcmp(var, "core.packedgitwindowsize")) {
 497                int pgsz_x2 = getpagesize() * 2;
 498                packed_git_window_size = git_config_int(var, value);
 499
 500                /* This value must be multiple of (pagesize * 2) */
 501                packed_git_window_size /= pgsz_x2;
 502                if (packed_git_window_size < 1)
 503                        packed_git_window_size = 1;
 504                packed_git_window_size *= pgsz_x2;
 505                return 0;
 506        }
 507
 508        if (!strcmp(var, "core.packedgitlimit")) {
 509                packed_git_limit = git_config_int(var, value);
 510                return 0;
 511        }
 512
 513        if (!strcmp(var, "core.deltabasecachelimit")) {
 514                delta_base_cache_limit = git_config_int(var, value);
 515                return 0;
 516        }
 517
 518        if (!strcmp(var, "core.autocrlf")) {
 519                if (value && !strcasecmp(value, "input")) {
 520                        auto_crlf = -1;
 521                        return 0;
 522                }
 523                auto_crlf = git_config_bool(var, value);
 524                return 0;
 525        }
 526
 527        if (!strcmp(var, "core.safecrlf")) {
 528                if (value && !strcasecmp(value, "warn")) {
 529                        safe_crlf = SAFE_CRLF_WARN;
 530                        return 0;
 531                }
 532                safe_crlf = git_config_bool(var, value);
 533                return 0;
 534        }
 535
 536        if (!strcmp(var, "core.notesref")) {
 537                notes_ref_name = xstrdup(value);
 538                return 0;
 539        }
 540
 541        if (!strcmp(var, "core.pager"))
 542                return git_config_string(&pager_program, var, value);
 543
 544        if (!strcmp(var, "core.editor"))
 545                return git_config_string(&editor_program, var, value);
 546
 547        if (!strcmp(var, "core.excludesfile"))
 548                return git_config_pathname(&excludes_file, var, value);
 549
 550        if (!strcmp(var, "core.whitespace")) {
 551                if (!value)
 552                        return config_error_nonbool(var);
 553                whitespace_rule_cfg = parse_whitespace_rule(value);
 554                return 0;
 555        }
 556
 557        if (!strcmp(var, "core.fsyncobjectfiles")) {
 558                fsync_object_files = git_config_bool(var, value);
 559                return 0;
 560        }
 561
 562        if (!strcmp(var, "core.preloadindex")) {
 563                core_preload_index = git_config_bool(var, value);
 564                return 0;
 565        }
 566
 567        if (!strcmp(var, "core.createobject")) {
 568                if (!strcmp(value, "rename"))
 569                        object_creation_mode = OBJECT_CREATION_USES_RENAMES;
 570                else if (!strcmp(value, "link"))
 571                        object_creation_mode = OBJECT_CREATION_USES_HARDLINKS;
 572                else
 573                        die("Invalid mode for object creation: %s", value);
 574                return 0;
 575        }
 576
 577        if (!strcmp(var, "core.sparsecheckout")) {
 578                core_apply_sparse_checkout = git_config_bool(var, value);
 579                return 0;
 580        }
 581
 582        /* Add other config variables here and to Documentation/config.txt. */
 583        return 0;
 584}
 585
 586static int git_default_user_config(const char *var, const char *value)
 587{
 588        if (!strcmp(var, "user.name")) {
 589                if (!value)
 590                        return config_error_nonbool(var);
 591                strlcpy(git_default_name, value, sizeof(git_default_name));
 592                user_ident_explicitly_given |= IDENT_NAME_GIVEN;
 593                return 0;
 594        }
 595
 596        if (!strcmp(var, "user.email")) {
 597                if (!value)
 598                        return config_error_nonbool(var);
 599                strlcpy(git_default_email, value, sizeof(git_default_email));
 600                user_ident_explicitly_given |= IDENT_MAIL_GIVEN;
 601                return 0;
 602        }
 603
 604        /* Add other config variables here and to Documentation/config.txt. */
 605        return 0;
 606}
 607
 608static int git_default_i18n_config(const char *var, const char *value)
 609{
 610        if (!strcmp(var, "i18n.commitencoding"))
 611                return git_config_string(&git_commit_encoding, var, value);
 612
 613        if (!strcmp(var, "i18n.logoutputencoding"))
 614                return git_config_string(&git_log_output_encoding, var, value);
 615
 616        /* Add other config variables here and to Documentation/config.txt. */
 617        return 0;
 618}
 619
 620static int git_default_branch_config(const char *var, const char *value)
 621{
 622        if (!strcmp(var, "branch.autosetupmerge")) {
 623                if (value && !strcasecmp(value, "always")) {
 624                        git_branch_track = BRANCH_TRACK_ALWAYS;
 625                        return 0;
 626                }
 627                git_branch_track = git_config_bool(var, value);
 628                return 0;
 629        }
 630        if (!strcmp(var, "branch.autosetuprebase")) {
 631                if (!value)
 632                        return config_error_nonbool(var);
 633                else if (!strcmp(value, "never"))
 634                        autorebase = AUTOREBASE_NEVER;
 635                else if (!strcmp(value, "local"))
 636                        autorebase = AUTOREBASE_LOCAL;
 637                else if (!strcmp(value, "remote"))
 638                        autorebase = AUTOREBASE_REMOTE;
 639                else if (!strcmp(value, "always"))
 640                        autorebase = AUTOREBASE_ALWAYS;
 641                else
 642                        return error("Malformed value for %s", var);
 643                return 0;
 644        }
 645
 646        /* Add other config variables here and to Documentation/config.txt. */
 647        return 0;
 648}
 649
 650static int git_default_push_config(const char *var, const char *value)
 651{
 652        if (!strcmp(var, "push.default")) {
 653                if (!value)
 654                        return config_error_nonbool(var);
 655                else if (!strcmp(value, "nothing"))
 656                        push_default = PUSH_DEFAULT_NOTHING;
 657                else if (!strcmp(value, "matching"))
 658                        push_default = PUSH_DEFAULT_MATCHING;
 659                else if (!strcmp(value, "tracking"))
 660                        push_default = PUSH_DEFAULT_TRACKING;
 661                else if (!strcmp(value, "current"))
 662                        push_default = PUSH_DEFAULT_CURRENT;
 663                else {
 664                        error("Malformed value for %s: %s", var, value);
 665                        return error("Must be one of nothing, matching, "
 666                                     "tracking or current.");
 667                }
 668                return 0;
 669        }
 670
 671        /* Add other config variables here and to Documentation/config.txt. */
 672        return 0;
 673}
 674
 675static int git_default_mailmap_config(const char *var, const char *value)
 676{
 677        if (!strcmp(var, "mailmap.file"))
 678                return git_config_string(&git_mailmap_file, var, value);
 679
 680        /* Add other config variables here and to Documentation/config.txt. */
 681        return 0;
 682}
 683
 684int git_default_config(const char *var, const char *value, void *dummy)
 685{
 686        if (!prefixcmp(var, "core."))
 687                return git_default_core_config(var, value);
 688
 689        if (!prefixcmp(var, "user."))
 690                return git_default_user_config(var, value);
 691
 692        if (!prefixcmp(var, "i18n."))
 693                return git_default_i18n_config(var, value);
 694
 695        if (!prefixcmp(var, "branch."))
 696                return git_default_branch_config(var, value);
 697
 698        if (!prefixcmp(var, "push."))
 699                return git_default_push_config(var, value);
 700
 701        if (!prefixcmp(var, "mailmap."))
 702                return git_default_mailmap_config(var, value);
 703
 704        if (!prefixcmp(var, "advice."))
 705                return git_default_advice_config(var, value);
 706
 707        if (!strcmp(var, "pager.color") || !strcmp(var, "color.pager")) {
 708                pager_use_color = git_config_bool(var,value);
 709                return 0;
 710        }
 711
 712        /* Add other config variables here and to Documentation/config.txt. */
 713        return 0;
 714}
 715
 716int git_config_from_file(config_fn_t fn, const char *filename, void *data)
 717{
 718        int ret;
 719        FILE *f = fopen(filename, "r");
 720
 721        ret = -1;
 722        if (f) {
 723                config_file = f;
 724                config_file_name = filename;
 725                config_linenr = 1;
 726                config_file_eof = 0;
 727                ret = git_parse_file(fn, data);
 728                fclose(f);
 729                config_file_name = NULL;
 730        }
 731        return ret;
 732}
 733
 734const char *git_etc_gitconfig(void)
 735{
 736        static const char *system_wide;
 737        if (!system_wide)
 738                system_wide = system_path(ETC_GITCONFIG);
 739        return system_wide;
 740}
 741
 742static int git_env_bool(const char *k, int def)
 743{
 744        const char *v = getenv(k);
 745        return v ? git_config_bool(k, v) : def;
 746}
 747
 748int git_config_system(void)
 749{
 750        return !git_env_bool("GIT_CONFIG_NOSYSTEM", 0);
 751}
 752
 753int git_config_global(void)
 754{
 755        return !git_env_bool("GIT_CONFIG_NOGLOBAL", 0);
 756}
 757
 758int git_config_from_parameters(config_fn_t fn, void *data)
 759{
 760        const struct config_item *ct;
 761        for (ct = config_parameters; ct; ct = ct->next)
 762                if (fn(ct->name, ct->value, data) < 0)
 763                        return -1;
 764        return 0;
 765}
 766
 767int git_config(config_fn_t fn, void *data)
 768{
 769        int ret = 0, found = 0;
 770        char *repo_config = NULL;
 771        const char *home = NULL;
 772
 773        /* Setting $GIT_CONFIG makes git read _only_ the given config file. */
 774        if (config_exclusive_filename)
 775                return git_config_from_file(fn, config_exclusive_filename, data);
 776        if (git_config_system() && !access(git_etc_gitconfig(), R_OK)) {
 777                ret += git_config_from_file(fn, git_etc_gitconfig(),
 778                                            data);
 779                found += 1;
 780        }
 781
 782        home = getenv("HOME");
 783        if (git_config_global() && home) {
 784                char *user_config = xstrdup(mkpath("%s/.gitconfig", home));
 785                if (!access(user_config, R_OK)) {
 786                        ret += git_config_from_file(fn, user_config, data);
 787                        found += 1;
 788                }
 789                free(user_config);
 790        }
 791
 792        repo_config = git_pathdup("config");
 793        if (!access(repo_config, R_OK)) {
 794                ret += git_config_from_file(fn, repo_config, data);
 795                found += 1;
 796        }
 797        free(repo_config);
 798
 799        if (config_parameters) {
 800                ret += git_config_from_parameters(fn, data);
 801                found += 1;
 802        }
 803
 804        if (found == 0)
 805                return -1;
 806        return ret;
 807}
 808
 809/*
 810 * Find all the stuff for git_config_set() below.
 811 */
 812
 813#define MAX_MATCHES 512
 814
 815static struct {
 816        int baselen;
 817        char *key;
 818        int do_not_match;
 819        regex_t *value_regex;
 820        int multi_replace;
 821        size_t offset[MAX_MATCHES];
 822        enum { START, SECTION_SEEN, SECTION_END_SEEN, KEY_SEEN } state;
 823        int seen;
 824} store;
 825
 826static int matches(const char *key, const char *value)
 827{
 828        return !strcmp(key, store.key) &&
 829                (store.value_regex == NULL ||
 830                 (store.do_not_match ^
 831                  !regexec(store.value_regex, value, 0, NULL, 0)));
 832}
 833
 834static int store_aux(const char *key, const char *value, void *cb)
 835{
 836        const char *ep;
 837        size_t section_len;
 838
 839        switch (store.state) {
 840        case KEY_SEEN:
 841                if (matches(key, value)) {
 842                        if (store.seen == 1 && store.multi_replace == 0) {
 843                                warning("%s has multiple values", key);
 844                        } else if (store.seen >= MAX_MATCHES) {
 845                                error("too many matches for %s", key);
 846                                return 1;
 847                        }
 848
 849                        store.offset[store.seen] = ftell(config_file);
 850                        store.seen++;
 851                }
 852                break;
 853        case SECTION_SEEN:
 854                /*
 855                 * What we are looking for is in store.key (both
 856                 * section and var), and its section part is baselen
 857                 * long.  We found key (again, both section and var).
 858                 * We would want to know if this key is in the same
 859                 * section as what we are looking for.  We already
 860                 * know we are in the same section as what should
 861                 * hold store.key.
 862                 */
 863                ep = strrchr(key, '.');
 864                section_len = ep - key;
 865
 866                if ((section_len != store.baselen) ||
 867                    memcmp(key, store.key, section_len+1)) {
 868                        store.state = SECTION_END_SEEN;
 869                        break;
 870                }
 871
 872                /*
 873                 * Do not increment matches: this is no match, but we
 874                 * just made sure we are in the desired section.
 875                 */
 876                store.offset[store.seen] = ftell(config_file);
 877                /* fallthru */
 878        case SECTION_END_SEEN:
 879        case START:
 880                if (matches(key, value)) {
 881                        store.offset[store.seen] = ftell(config_file);
 882                        store.state = KEY_SEEN;
 883                        store.seen++;
 884                } else {
 885                        if (strrchr(key, '.') - key == store.baselen &&
 886                              !strncmp(key, store.key, store.baselen)) {
 887                                        store.state = SECTION_SEEN;
 888                                        store.offset[store.seen] = ftell(config_file);
 889                        }
 890                }
 891        }
 892        return 0;
 893}
 894
 895static int write_error(const char *filename)
 896{
 897        error("failed to write new configuration file %s", filename);
 898
 899        /* Same error code as "failed to rename". */
 900        return 4;
 901}
 902
 903static int store_write_section(int fd, const char *key)
 904{
 905        const char *dot;
 906        int i, success;
 907        struct strbuf sb = STRBUF_INIT;
 908
 909        dot = memchr(key, '.', store.baselen);
 910        if (dot) {
 911                strbuf_addf(&sb, "[%.*s \"", (int)(dot - key), key);
 912                for (i = dot - key + 1; i < store.baselen; i++) {
 913                        if (key[i] == '"' || key[i] == '\\')
 914                                strbuf_addch(&sb, '\\');
 915                        strbuf_addch(&sb, key[i]);
 916                }
 917                strbuf_addstr(&sb, "\"]\n");
 918        } else {
 919                strbuf_addf(&sb, "[%.*s]\n", store.baselen, key);
 920        }
 921
 922        success = write_in_full(fd, sb.buf, sb.len) == sb.len;
 923        strbuf_release(&sb);
 924
 925        return success;
 926}
 927
 928static int store_write_pair(int fd, const char *key, const char *value)
 929{
 930        int i, success;
 931        int length = strlen(key + store.baselen + 1);
 932        const char *quote = "";
 933        struct strbuf sb = STRBUF_INIT;
 934
 935        /*
 936         * Check to see if the value needs to be surrounded with a dq pair.
 937         * Note that problematic characters are always backslash-quoted; this
 938         * check is about not losing leading or trailing SP and strings that
 939         * follow beginning-of-comment characters (i.e. ';' and '#') by the
 940         * configuration parser.
 941         */
 942        if (value[0] == ' ')
 943                quote = "\"";
 944        for (i = 0; value[i]; i++)
 945                if (value[i] == ';' || value[i] == '#')
 946                        quote = "\"";
 947        if (i && value[i - 1] == ' ')
 948                quote = "\"";
 949
 950        strbuf_addf(&sb, "\t%.*s = %s",
 951                    length, key + store.baselen + 1, quote);
 952
 953        for (i = 0; value[i]; i++)
 954                switch (value[i]) {
 955                case '\n':
 956                        strbuf_addstr(&sb, "\\n");
 957                        break;
 958                case '\t':
 959                        strbuf_addstr(&sb, "\\t");
 960                        break;
 961                case '"':
 962                case '\\':
 963                        strbuf_addch(&sb, '\\');
 964                default:
 965                        strbuf_addch(&sb, value[i]);
 966                        break;
 967                }
 968        strbuf_addf(&sb, "%s\n", quote);
 969
 970        success = write_in_full(fd, sb.buf, sb.len) == sb.len;
 971        strbuf_release(&sb);
 972
 973        return success;
 974}
 975
 976static ssize_t find_beginning_of_line(const char *contents, size_t size,
 977        size_t offset_, int *found_bracket)
 978{
 979        size_t equal_offset = size, bracket_offset = size;
 980        ssize_t offset;
 981
 982contline:
 983        for (offset = offset_-2; offset > 0
 984                        && contents[offset] != '\n'; offset--)
 985                switch (contents[offset]) {
 986                        case '=': equal_offset = offset; break;
 987                        case ']': bracket_offset = offset; break;
 988                }
 989        if (offset > 0 && contents[offset-1] == '\\') {
 990                offset_ = offset;
 991                goto contline;
 992        }
 993        if (bracket_offset < equal_offset) {
 994                *found_bracket = 1;
 995                offset = bracket_offset+1;
 996        } else
 997                offset++;
 998
 999        return offset;
1000}
1001
1002int git_config_set(const char *key, const char *value)
1003{
1004        return git_config_set_multivar(key, value, NULL, 0);
1005}
1006
1007/*
1008 * If value==NULL, unset in (remove from) config,
1009 * if value_regex!=NULL, disregard key/value pairs where value does not match.
1010 * if multi_replace==0, nothing, or only one matching key/value is replaced,
1011 *     else all matching key/values (regardless how many) are removed,
1012 *     before the new pair is written.
1013 *
1014 * Returns 0 on success.
1015 *
1016 * This function does this:
1017 *
1018 * - it locks the config file by creating ".git/config.lock"
1019 *
1020 * - it then parses the config using store_aux() as validator to find
1021 *   the position on the key/value pair to replace. If it is to be unset,
1022 *   it must be found exactly once.
1023 *
1024 * - the config file is mmap()ed and the part before the match (if any) is
1025 *   written to the lock file, then the changed part and the rest.
1026 *
1027 * - the config file is removed and the lock file rename()d to it.
1028 *
1029 */
1030int git_config_set_multivar(const char *key, const char *value,
1031        const char *value_regex, int multi_replace)
1032{
1033        int i, dot;
1034        int fd = -1, in_fd;
1035        int ret;
1036        char *config_filename;
1037        struct lock_file *lock = NULL;
1038        const char *last_dot = strrchr(key, '.');
1039
1040        if (config_exclusive_filename)
1041                config_filename = xstrdup(config_exclusive_filename);
1042        else
1043                config_filename = git_pathdup("config");
1044
1045        /*
1046         * Since "key" actually contains the section name and the real
1047         * key name separated by a dot, we have to know where the dot is.
1048         */
1049
1050        if (last_dot == NULL) {
1051                error("key does not contain a section: %s", key);
1052                ret = 2;
1053                goto out_free;
1054        }
1055        store.baselen = last_dot - key;
1056
1057        store.multi_replace = multi_replace;
1058
1059        /*
1060         * Validate the key and while at it, lower case it for matching.
1061         */
1062        store.key = xmalloc(strlen(key) + 1);
1063        dot = 0;
1064        for (i = 0; key[i]; i++) {
1065                unsigned char c = key[i];
1066                if (c == '.')
1067                        dot = 1;
1068                /* Leave the extended basename untouched.. */
1069                if (!dot || i > store.baselen) {
1070                        if (!iskeychar(c) || (i == store.baselen+1 && !isalpha(c))) {
1071                                error("invalid key: %s", key);
1072                                free(store.key);
1073                                ret = 1;
1074                                goto out_free;
1075                        }
1076                        c = tolower(c);
1077                } else if (c == '\n') {
1078                        error("invalid key (newline): %s", key);
1079                        free(store.key);
1080                        ret = 1;
1081                        goto out_free;
1082                }
1083                store.key[i] = c;
1084        }
1085        store.key[i] = 0;
1086
1087        /*
1088         * The lock serves a purpose in addition to locking: the new
1089         * contents of .git/config will be written into it.
1090         */
1091        lock = xcalloc(sizeof(struct lock_file), 1);
1092        fd = hold_lock_file_for_update(lock, config_filename, 0);
1093        if (fd < 0) {
1094                error("could not lock config file %s: %s", config_filename, strerror(errno));
1095                free(store.key);
1096                ret = -1;
1097                goto out_free;
1098        }
1099
1100        /*
1101         * If .git/config does not exist yet, write a minimal version.
1102         */
1103        in_fd = open(config_filename, O_RDONLY);
1104        if ( in_fd < 0 ) {
1105                free(store.key);
1106
1107                if ( ENOENT != errno ) {
1108                        error("opening %s: %s", config_filename,
1109                              strerror(errno));
1110                        ret = 3; /* same as "invalid config file" */
1111                        goto out_free;
1112                }
1113                /* if nothing to unset, error out */
1114                if (value == NULL) {
1115                        ret = 5;
1116                        goto out_free;
1117                }
1118
1119                store.key = (char *)key;
1120                if (!store_write_section(fd, key) ||
1121                    !store_write_pair(fd, key, value))
1122                        goto write_err_out;
1123        } else {
1124                struct stat st;
1125                char *contents;
1126                size_t contents_sz, copy_begin, copy_end;
1127                int i, new_line = 0;
1128
1129                if (value_regex == NULL)
1130                        store.value_regex = NULL;
1131                else {
1132                        if (value_regex[0] == '!') {
1133                                store.do_not_match = 1;
1134                                value_regex++;
1135                        } else
1136                                store.do_not_match = 0;
1137
1138                        store.value_regex = (regex_t*)xmalloc(sizeof(regex_t));
1139                        if (regcomp(store.value_regex, value_regex,
1140                                        REG_EXTENDED)) {
1141                                error("invalid pattern: %s", value_regex);
1142                                free(store.value_regex);
1143                                ret = 6;
1144                                goto out_free;
1145                        }
1146                }
1147
1148                store.offset[0] = 0;
1149                store.state = START;
1150                store.seen = 0;
1151
1152                /*
1153                 * After this, store.offset will contain the *end* offset
1154                 * of the last match, or remain at 0 if no match was found.
1155                 * As a side effect, we make sure to transform only a valid
1156                 * existing config file.
1157                 */
1158                if (git_config_from_file(store_aux, config_filename, NULL)) {
1159                        error("invalid config file %s", config_filename);
1160                        free(store.key);
1161                        if (store.value_regex != NULL) {
1162                                regfree(store.value_regex);
1163                                free(store.value_regex);
1164                        }
1165                        ret = 3;
1166                        goto out_free;
1167                }
1168
1169                free(store.key);
1170                if (store.value_regex != NULL) {
1171                        regfree(store.value_regex);
1172                        free(store.value_regex);
1173                }
1174
1175                /* if nothing to unset, or too many matches, error out */
1176                if ((store.seen == 0 && value == NULL) ||
1177                                (store.seen > 1 && multi_replace == 0)) {
1178                        ret = 5;
1179                        goto out_free;
1180                }
1181
1182                fstat(in_fd, &st);
1183                contents_sz = xsize_t(st.st_size);
1184                contents = xmmap(NULL, contents_sz, PROT_READ,
1185                        MAP_PRIVATE, in_fd, 0);
1186                close(in_fd);
1187
1188                if (store.seen == 0)
1189                        store.seen = 1;
1190
1191                for (i = 0, copy_begin = 0; i < store.seen; i++) {
1192                        if (store.offset[i] == 0) {
1193                                store.offset[i] = copy_end = contents_sz;
1194                        } else if (store.state != KEY_SEEN) {
1195                                copy_end = store.offset[i];
1196                        } else
1197                                copy_end = find_beginning_of_line(
1198                                        contents, contents_sz,
1199                                        store.offset[i]-2, &new_line);
1200
1201                        if (copy_end > 0 && contents[copy_end-1] != '\n')
1202                                new_line = 1;
1203
1204                        /* write the first part of the config */
1205                        if (copy_end > copy_begin) {
1206                                if (write_in_full(fd, contents + copy_begin,
1207                                                  copy_end - copy_begin) <
1208                                    copy_end - copy_begin)
1209                                        goto write_err_out;
1210                                if (new_line &&
1211                                    write_str_in_full(fd, "\n") != 1)
1212                                        goto write_err_out;
1213                        }
1214                        copy_begin = store.offset[i];
1215                }
1216
1217                /* write the pair (value == NULL means unset) */
1218                if (value != NULL) {
1219                        if (store.state == START) {
1220                                if (!store_write_section(fd, key))
1221                                        goto write_err_out;
1222                        }
1223                        if (!store_write_pair(fd, key, value))
1224                                goto write_err_out;
1225                }
1226
1227                /* write the rest of the config */
1228                if (copy_begin < contents_sz)
1229                        if (write_in_full(fd, contents + copy_begin,
1230                                          contents_sz - copy_begin) <
1231                            contents_sz - copy_begin)
1232                                goto write_err_out;
1233
1234                munmap(contents, contents_sz);
1235        }
1236
1237        if (commit_lock_file(lock) < 0) {
1238                error("could not commit config file %s", config_filename);
1239                ret = 4;
1240                goto out_free;
1241        }
1242
1243        /*
1244         * lock is committed, so don't try to roll it back below.
1245         * NOTE: Since lockfile.c keeps a linked list of all created
1246         * lock_file structures, it isn't safe to free(lock).  It's
1247         * better to just leave it hanging around.
1248         */
1249        lock = NULL;
1250        ret = 0;
1251
1252out_free:
1253        if (lock)
1254                rollback_lock_file(lock);
1255        free(config_filename);
1256        return ret;
1257
1258write_err_out:
1259        ret = write_error(lock->filename);
1260        goto out_free;
1261
1262}
1263
1264static int section_name_match (const char *buf, const char *name)
1265{
1266        int i = 0, j = 0, dot = 0;
1267        if (buf[i] != '[')
1268                return 0;
1269        for (i = 1; buf[i] && buf[i] != ']'; i++) {
1270                if (!dot && isspace(buf[i])) {
1271                        dot = 1;
1272                        if (name[j++] != '.')
1273                                break;
1274                        for (i++; isspace(buf[i]); i++)
1275                                ; /* do nothing */
1276                        if (buf[i] != '"')
1277                                break;
1278                        continue;
1279                }
1280                if (buf[i] == '\\' && dot)
1281                        i++;
1282                else if (buf[i] == '"' && dot) {
1283                        for (i++; isspace(buf[i]); i++)
1284                                ; /* do_nothing */
1285                        break;
1286                }
1287                if (buf[i] != name[j++])
1288                        break;
1289        }
1290        if (buf[i] == ']' && name[j] == 0) {
1291                /*
1292                 * We match, now just find the right length offset by
1293                 * gobbling up any whitespace after it, as well
1294                 */
1295                i++;
1296                for (; buf[i] && isspace(buf[i]); i++)
1297                        ; /* do nothing */
1298                return i;
1299        }
1300        return 0;
1301}
1302
1303/* if new_name == NULL, the section is removed instead */
1304int git_config_rename_section(const char *old_name, const char *new_name)
1305{
1306        int ret = 0, remove = 0;
1307        char *config_filename;
1308        struct lock_file *lock = xcalloc(sizeof(struct lock_file), 1);
1309        int out_fd;
1310        char buf[1024];
1311
1312        if (config_exclusive_filename)
1313                config_filename = xstrdup(config_exclusive_filename);
1314        else
1315                config_filename = git_pathdup("config");
1316        out_fd = hold_lock_file_for_update(lock, config_filename, 0);
1317        if (out_fd < 0) {
1318                ret = error("could not lock config file %s", config_filename);
1319                goto out;
1320        }
1321
1322        if (!(config_file = fopen(config_filename, "rb"))) {
1323                /* no config file means nothing to rename, no error */
1324                goto unlock_and_out;
1325        }
1326
1327        while (fgets(buf, sizeof(buf), config_file)) {
1328                int i;
1329                int length;
1330                char *output = buf;
1331                for (i = 0; buf[i] && isspace(buf[i]); i++)
1332                        ; /* do nothing */
1333                if (buf[i] == '[') {
1334                        /* it's a section */
1335                        int offset = section_name_match(&buf[i], old_name);
1336                        if (offset > 0) {
1337                                ret++;
1338                                if (new_name == NULL) {
1339                                        remove = 1;
1340                                        continue;
1341                                }
1342                                store.baselen = strlen(new_name);
1343                                if (!store_write_section(out_fd, new_name)) {
1344                                        ret = write_error(lock->filename);
1345                                        goto out;
1346                                }
1347                                /*
1348                                 * We wrote out the new section, with
1349                                 * a newline, now skip the old
1350                                 * section's length
1351                                 */
1352                                output += offset + i;
1353                                if (strlen(output) > 0) {
1354                                        /*
1355                                         * More content means there's
1356                                         * a declaration to put on the
1357                                         * next line; indent with a
1358                                         * tab
1359                                         */
1360                                        output -= 1;
1361                                        output[0] = '\t';
1362                                }
1363                        }
1364                        remove = 0;
1365                }
1366                if (remove)
1367                        continue;
1368                length = strlen(output);
1369                if (write_in_full(out_fd, output, length) != length) {
1370                        ret = write_error(lock->filename);
1371                        goto out;
1372                }
1373        }
1374        fclose(config_file);
1375 unlock_and_out:
1376        if (commit_lock_file(lock) < 0)
1377                ret = error("could not commit config file %s", config_filename);
1378 out:
1379        free(config_filename);
1380        return ret;
1381}
1382
1383/*
1384 * Call this to report error for your variable that should not
1385 * get a boolean value (i.e. "[my] var" means "true").
1386 */
1387int config_error_nonbool(const char *var)
1388{
1389        return error("Missing value for '%s'", var);
1390}