Andrew's git / gitweb.git / config.c
?
config.con commit git-branch -D: make it work even when on a yet-to-be-born branch (67affd5)
   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 <regex.h>
  10
  11#define MAXNAME (256)
  12
  13static FILE *config_file;
  14static const char *config_file_name;
  15static int config_linenr;
  16static int get_next_char(void)
  17{
  18        int c;
  19        FILE *f;
  20
  21        c = '\n';
  22        if ((f = config_file) != NULL) {
  23                c = fgetc(f);
  24                if (c == '\r') {
  25                        /* DOS like systems */
  26                        c = fgetc(f);
  27                        if (c != '\n') {
  28                                ungetc(c, f);
  29                                c = '\r';
  30                        }
  31                }
  32                if (c == '\n')
  33                        config_linenr++;
  34                if (c == EOF) {
  35                        config_file = NULL;
  36                        c = '\n';
  37                }
  38        }
  39        return c;
  40}
  41
  42static char *parse_value(void)
  43{
  44        static char value[1024];
  45        int quote = 0, comment = 0, len = 0, space = 0;
  46
  47        for (;;) {
  48                int c = get_next_char();
  49                if (len >= sizeof(value))
  50                        return NULL;
  51                if (c == '\n') {
  52                        if (quote)
  53                                return NULL;
  54                        value[len] = 0;
  55                        return value;
  56                }
  57                if (comment)
  58                        continue;
  59                if (isspace(c) && !quote) {
  60                        space = 1;
  61                        continue;
  62                }
  63                if (!quote) {
  64                        if (c == ';' || c == '#') {
  65                                comment = 1;
  66                                continue;
  67                        }
  68                }
  69                if (space) {
  70                        if (len)
  71                                value[len++] = ' ';
  72                        space = 0;
  73                }
  74                if (c == '\\') {
  75                        c = get_next_char();
  76                        switch (c) {
  77                        case '\n':
  78                                continue;
  79                        case 't':
  80                                c = '\t';
  81                                break;
  82                        case 'b':
  83                                c = '\b';
  84                                break;
  85                        case 'n':
  86                                c = '\n';
  87                                break;
  88                        /* Some characters escape as themselves */
  89                        case '\\': case '"':
  90                                break;
  91                        /* Reject unknown escape sequences */
  92                        default:
  93                                return NULL;
  94                        }
  95                        value[len++] = c;
  96                        continue;
  97                }
  98                if (c == '"') {
  99                        quote = 1-quote;
 100                        continue;
 101                }
 102                value[len++] = c;
 103        }
 104}
 105
 106static inline int iskeychar(int c)
 107{
 108        return isalnum(c) || c == '-';
 109}
 110
 111static int get_value(config_fn_t fn, char *name, unsigned int len)
 112{
 113        int c;
 114        char *value;
 115
 116        /* Get the full name */
 117        for (;;) {
 118                c = get_next_char();
 119                if (c == EOF)
 120                        break;
 121                if (!iskeychar(c))
 122                        break;
 123                name[len++] = tolower(c);
 124                if (len >= MAXNAME)
 125                        return -1;
 126        }
 127        name[len] = 0;
 128        while (c == ' ' || c == '\t')
 129                c = get_next_char();
 130
 131        value = NULL;
 132        if (c != '\n') {
 133                if (c != '=')
 134                        return -1;
 135                value = parse_value();
 136                if (!value)
 137                        return -1;
 138        }
 139        return fn(name, value);
 140}
 141
 142static int get_extended_base_var(char *name, int baselen, int c)
 143{
 144        do {
 145                if (c == '\n')
 146                        return -1;
 147                c = get_next_char();
 148        } while (isspace(c));
 149
 150        /* We require the format to be '[base "extension"]' */
 151        if (c != '"')
 152                return -1;
 153        name[baselen++] = '.';
 154
 155        for (;;) {
 156                int c = get_next_char();
 157                if (c == '\n')
 158                        return -1;
 159                if (c == '"')
 160                        break;
 161                if (c == '\\') {
 162                        c = get_next_char();
 163                        if (c == '\n')
 164                                return -1;
 165                }
 166                name[baselen++] = c;
 167                if (baselen > MAXNAME / 2)
 168                        return -1;
 169        }
 170
 171        /* Final ']' */
 172        if (get_next_char() != ']')
 173                return -1;
 174        return baselen;
 175}
 176
 177static int get_base_var(char *name)
 178{
 179        int baselen = 0;
 180
 181        for (;;) {
 182                int c = get_next_char();
 183                if (c == EOF)
 184                        return -1;
 185                if (c == ']')
 186                        return baselen;
 187                if (isspace(c))
 188                        return get_extended_base_var(name, baselen, c);
 189                if (!iskeychar(c) && c != '.')
 190                        return -1;
 191                if (baselen > MAXNAME / 2)
 192                        return -1;
 193                name[baselen++] = tolower(c);
 194        }
 195}
 196
 197static int git_parse_file(config_fn_t fn)
 198{
 199        int comment = 0;
 200        int baselen = 0;
 201        static char var[MAXNAME];
 202
 203        for (;;) {
 204                int c = get_next_char();
 205                if (c == '\n') {
 206                        /* EOF? */
 207                        if (!config_file)
 208                                return 0;
 209                        comment = 0;
 210                        continue;
 211                }
 212                if (comment || isspace(c))
 213                        continue;
 214                if (c == '#' || c == ';') {
 215                        comment = 1;
 216                        continue;
 217                }
 218                if (c == '[') {
 219                        baselen = get_base_var(var);
 220                        if (baselen <= 0)
 221                                break;
 222                        var[baselen++] = '.';
 223                        var[baselen] = 0;
 224                        continue;
 225                }
 226                if (!isalpha(c))
 227                        break;
 228                var[baselen] = tolower(c);
 229                if (get_value(fn, var, baselen+1) < 0)
 230                        break;
 231        }
 232        die("bad config file line %d in %s", config_linenr, config_file_name);
 233}
 234
 235int git_config_int(const char *name, const char *value)
 236{
 237        if (value && *value) {
 238                char *end;
 239                int val = strtol(value, &end, 0);
 240                if (!*end)
 241                        return val;
 242        }
 243        die("bad config value for '%s' in %s", name, config_file_name);
 244}
 245
 246int git_config_bool(const char *name, const char *value)
 247{
 248        if (!value)
 249                return 1;
 250        if (!*value)
 251                return 0;
 252        if (!strcasecmp(value, "true") || !strcasecmp(value, "yes"))
 253                return 1;
 254        if (!strcasecmp(value, "false") || !strcasecmp(value, "no"))
 255                return 0;
 256        return git_config_int(name, value) != 0;
 257}
 258
 259int git_default_config(const char *var, const char *value)
 260{
 261        /* This needs a better name */
 262        if (!strcmp(var, "core.filemode")) {
 263                trust_executable_bit = git_config_bool(var, value);
 264                return 0;
 265        }
 266
 267        if (!strcmp(var, "core.ignorestat")) {
 268                assume_unchanged = git_config_bool(var, value);
 269                return 0;
 270        }
 271
 272        if (!strcmp(var, "core.prefersymlinkrefs")) {
 273                prefer_symlink_refs = git_config_bool(var, value);
 274                return 0;
 275        }
 276
 277        if (!strcmp(var, "core.logallrefupdates")) {
 278                log_all_ref_updates = git_config_bool(var, value);
 279                return 0;
 280        }
 281
 282        if (!strcmp(var, "core.warnambiguousrefs")) {
 283                warn_ambiguous_refs = git_config_bool(var, value);
 284                return 0;
 285        }
 286
 287        if (!strcmp(var, "core.legacyheaders")) {
 288                use_legacy_headers = git_config_bool(var, value);
 289                return 0;
 290        }
 291
 292        if (!strcmp(var, "core.compression")) {
 293                int level = git_config_int(var, value);
 294                if (level == -1)
 295                        level = Z_DEFAULT_COMPRESSION;
 296                else if (level < 0 || level > Z_BEST_COMPRESSION)
 297                        die("bad zlib compression level %d", level);
 298                zlib_compression_level = level;
 299                return 0;
 300        }
 301
 302        if (!strcmp(var, "user.name")) {
 303                strlcpy(git_default_name, value, sizeof(git_default_name));
 304                return 0;
 305        }
 306
 307        if (!strcmp(var, "user.email")) {
 308                strlcpy(git_default_email, value, sizeof(git_default_email));
 309                return 0;
 310        }
 311
 312        if (!strcmp(var, "i18n.commitencoding")) {
 313                strlcpy(git_commit_encoding, value, sizeof(git_commit_encoding));
 314                return 0;
 315        }
 316
 317        if (!strcmp(var, "pager.color")) {
 318                pager_use_color = git_config_bool(var,value);
 319                return 0;
 320        }
 321
 322        /* Add other config variables here and to Documentation/config.txt. */
 323        return 0;
 324}
 325
 326int git_config_from_file(config_fn_t fn, const char *filename)
 327{
 328        int ret;
 329        FILE *f = fopen(filename, "r");
 330
 331        ret = -1;
 332        if (f) {
 333                config_file = f;
 334                config_file_name = filename;
 335                config_linenr = 1;
 336                ret = git_parse_file(fn);
 337                fclose(f);
 338                config_file_name = NULL;
 339        }
 340        return ret;
 341}
 342
 343int git_config(config_fn_t fn)
 344{
 345        int ret = 0;
 346        char *repo_config = NULL;
 347        const char *home = NULL, *filename;
 348
 349        /* $GIT_CONFIG makes git read _only_ the given config file,
 350         * $GIT_CONFIG_LOCAL will make it process it in addition to the
 351         * global config file, the same way it would the per-repository
 352         * config file otherwise. */
 353        filename = getenv("GIT_CONFIG");
 354        if (!filename) {
 355                home = getenv("HOME");
 356                filename = getenv("GIT_CONFIG_LOCAL");
 357                if (!filename)
 358                        filename = repo_config = xstrdup(git_path("config"));
 359        }
 360
 361        if (home) {
 362                char *user_config = xstrdup(mkpath("%s/.gitconfig", home));
 363                if (!access(user_config, R_OK))
 364                        ret = git_config_from_file(fn, user_config);
 365                free(user_config);
 366        }
 367
 368        ret += git_config_from_file(fn, filename);
 369        free(repo_config);
 370        return ret;
 371}
 372
 373/*
 374 * Find all the stuff for git_config_set() below.
 375 */
 376
 377#define MAX_MATCHES 512
 378
 379static struct {
 380        int baselen;
 381        char* key;
 382        int do_not_match;
 383        regex_t* value_regex;
 384        int multi_replace;
 385        off_t offset[MAX_MATCHES];
 386        enum { START, SECTION_SEEN, SECTION_END_SEEN, KEY_SEEN } state;
 387        int seen;
 388} store;
 389
 390static int matches(const char* key, const char* value)
 391{
 392        return !strcmp(key, store.key) &&
 393                (store.value_regex == NULL ||
 394                 (store.do_not_match ^
 395                  !regexec(store.value_regex, value, 0, NULL, 0)));
 396}
 397
 398static int store_aux(const char* key, const char* value)
 399{
 400        switch (store.state) {
 401        case KEY_SEEN:
 402                if (matches(key, value)) {
 403                        if (store.seen == 1 && store.multi_replace == 0) {
 404                                fprintf(stderr,
 405                                        "Warning: %s has multiple values\n",
 406                                        key);
 407                        } else if (store.seen >= MAX_MATCHES) {
 408                                fprintf(stderr, "Too many matches\n");
 409                                return 1;
 410                        }
 411
 412                        store.offset[store.seen] = ftell(config_file);
 413                        store.seen++;
 414                }
 415                break;
 416        case SECTION_SEEN:
 417                if (strncmp(key, store.key, store.baselen+1)) {
 418                        store.state = SECTION_END_SEEN;
 419                        break;
 420                } else
 421                        /* do not increment matches: this is no match */
 422                        store.offset[store.seen] = ftell(config_file);
 423                /* fallthru */
 424        case SECTION_END_SEEN:
 425        case START:
 426                if (matches(key, value)) {
 427                        store.offset[store.seen] = ftell(config_file);
 428                        store.state = KEY_SEEN;
 429                        store.seen++;
 430                } else {
 431                        if (strrchr(key, '.') - key == store.baselen &&
 432                              !strncmp(key, store.key, store.baselen)) {
 433                                        store.state = SECTION_SEEN;
 434                                        store.offset[store.seen] = ftell(config_file);
 435                        }
 436                }
 437        }
 438        return 0;
 439}
 440
 441static void store_write_section(int fd, const char* key)
 442{
 443        const char *dot = strchr(key, '.');
 444        int len1 = store.baselen, len2 = -1;
 445
 446        dot = strchr(key, '.');
 447        if (dot) {
 448                int dotlen = dot - key;
 449                if (dotlen < len1) {
 450                        len2 = len1 - dotlen - 1;
 451                        len1 = dotlen;
 452                }
 453        }
 454
 455        write(fd, "[", 1);
 456        write(fd, key, len1);
 457        if (len2 >= 0) {
 458                write(fd, " \"", 2);
 459                while (--len2 >= 0) {
 460                        unsigned char c = *++dot;
 461                        if (c == '"')
 462                                write(fd, "\\", 1);
 463                        write(fd, &c, 1);
 464                }
 465                write(fd, "\"", 1);
 466        }
 467        write(fd, "]\n", 2);
 468}
 469
 470static void store_write_pair(int fd, const char* key, const char* value)
 471{
 472        int i;
 473
 474        write(fd, "\t", 1);
 475        write(fd, key+store.baselen+1,
 476                strlen(key+store.baselen+1));
 477        write(fd, " = ", 3);
 478        for (i = 0; value[i]; i++)
 479                switch (value[i]) {
 480                case '\n': write(fd, "\\n", 2); break;
 481                case '\t': write(fd, "\\t", 2); break;
 482                case '"': case '\\': write(fd, "\\", 1);
 483                default: write(fd, value+i, 1);
 484        }
 485        write(fd, "\n", 1);
 486}
 487
 488static int find_beginning_of_line(const char* contents, int size,
 489        int offset_, int* found_bracket)
 490{
 491        int equal_offset = size, bracket_offset = size;
 492        int offset;
 493
 494        for (offset = offset_-2; offset > 0 
 495                        && contents[offset] != '\n'; offset--)
 496                switch (contents[offset]) {
 497                        case '=': equal_offset = offset; break;
 498                        case ']': bracket_offset = offset; break;
 499                }
 500        if (bracket_offset < equal_offset) {
 501                *found_bracket = 1;
 502                offset = bracket_offset+1;
 503        } else
 504                offset++;
 505
 506        return offset;
 507}
 508
 509int git_config_set(const char* key, const char* value)
 510{
 511        return git_config_set_multivar(key, value, NULL, 0);
 512}
 513
 514/*
 515 * If value==NULL, unset in (remove from) config,
 516 * if value_regex!=NULL, disregard key/value pairs where value does not match.
 517 * if multi_replace==0, nothing, or only one matching key/value is replaced,
 518 *     else all matching key/values (regardless how many) are removed,
 519 *     before the new pair is written.
 520 *
 521 * Returns 0 on success.
 522 *
 523 * This function does this:
 524 *
 525 * - it locks the config file by creating ".git/config.lock"
 526 *
 527 * - it then parses the config using store_aux() as validator to find
 528 *   the position on the key/value pair to replace. If it is to be unset,
 529 *   it must be found exactly once.
 530 *
 531 * - the config file is mmap()ed and the part before the match (if any) is
 532 *   written to the lock file, then the changed part and the rest.
 533 *
 534 * - the config file is removed and the lock file rename()d to it.
 535 *
 536 */
 537int git_config_set_multivar(const char* key, const char* value,
 538        const char* value_regex, int multi_replace)
 539{
 540        int i, dot;
 541        int fd = -1, in_fd;
 542        int ret;
 543        char* config_filename;
 544        char* lock_file;
 545        const char* last_dot = strrchr(key, '.');
 546
 547        config_filename = getenv("GIT_CONFIG");
 548        if (!config_filename) {
 549                config_filename = getenv("GIT_CONFIG_LOCAL");
 550                if (!config_filename)
 551                        config_filename  = git_path("config");
 552        }
 553        config_filename = xstrdup(config_filename);
 554        lock_file = xstrdup(mkpath("%s.lock", config_filename));
 555
 556        /*
 557         * Since "key" actually contains the section name and the real
 558         * key name separated by a dot, we have to know where the dot is.
 559         */
 560
 561        if (last_dot == NULL) {
 562                fprintf(stderr, "key does not contain a section: %s\n", key);
 563                ret = 2;
 564                goto out_free;
 565        }
 566        store.baselen = last_dot - key;
 567
 568        store.multi_replace = multi_replace;
 569
 570        /*
 571         * Validate the key and while at it, lower case it for matching.
 572         */
 573        store.key = xmalloc(strlen(key) + 1);
 574        dot = 0;
 575        for (i = 0; key[i]; i++) {
 576                unsigned char c = key[i];
 577                if (c == '.')
 578                        dot = 1;
 579                /* Leave the extended basename untouched.. */
 580                if (!dot || i > store.baselen) {
 581                        if (!iskeychar(c) || (i == store.baselen+1 && !isalpha(c))) {
 582                                fprintf(stderr, "invalid key: %s\n", key);
 583                                free(store.key);
 584                                ret = 1;
 585                                goto out_free;
 586                        }
 587                        c = tolower(c);
 588                }
 589                store.key[i] = c;
 590        }
 591        store.key[i] = 0;
 592
 593        /*
 594         * The lock_file serves a purpose in addition to locking: the new
 595         * contents of .git/config will be written into it.
 596         */
 597        fd = open(lock_file, O_WRONLY | O_CREAT | O_EXCL, 0666);
 598        if (fd < 0 || adjust_shared_perm(lock_file)) {
 599                fprintf(stderr, "could not lock config file\n");
 600                free(store.key);
 601                ret = -1;
 602                goto out_free;
 603        }
 604
 605        /*
 606         * If .git/config does not exist yet, write a minimal version.
 607         */
 608        in_fd = open(config_filename, O_RDONLY);
 609        if ( in_fd < 0 ) {
 610                free(store.key);
 611
 612                if ( ENOENT != errno ) {
 613                        error("opening %s: %s", config_filename,
 614                              strerror(errno));
 615                        ret = 3; /* same as "invalid config file" */
 616                        goto out_free;
 617                }
 618                /* if nothing to unset, error out */
 619                if (value == NULL) {
 620                        ret = 5;
 621                        goto out_free;
 622                }
 623
 624                store.key = (char*)key;
 625                store_write_section(fd, key);
 626                store_write_pair(fd, key, value);
 627        } else{
 628                struct stat st;
 629                char* contents;
 630                int i, copy_begin, copy_end, new_line = 0;
 631
 632                if (value_regex == NULL)
 633                        store.value_regex = NULL;
 634                else {
 635                        if (value_regex[0] == '!') {
 636                                store.do_not_match = 1;
 637                                value_regex++;
 638                        } else
 639                                store.do_not_match = 0;
 640
 641                        store.value_regex = (regex_t*)xmalloc(sizeof(regex_t));
 642                        if (regcomp(store.value_regex, value_regex,
 643                                        REG_EXTENDED)) {
 644                                fprintf(stderr, "Invalid pattern: %s\n",
 645                                        value_regex);
 646                                free(store.value_regex);
 647                                ret = 6;
 648                                goto out_free;
 649                        }
 650                }
 651
 652                store.offset[0] = 0;
 653                store.state = START;
 654                store.seen = 0;
 655
 656                /*
 657                 * After this, store.offset will contain the *end* offset
 658                 * of the last match, or remain at 0 if no match was found.
 659                 * As a side effect, we make sure to transform only a valid
 660                 * existing config file.
 661                 */
 662                if (git_config_from_file(store_aux, config_filename)) {
 663                        fprintf(stderr, "invalid config file\n");
 664                        free(store.key);
 665                        if (store.value_regex != NULL) {
 666                                regfree(store.value_regex);
 667                                free(store.value_regex);
 668                        }
 669                        ret = 3;
 670                        goto out_free;
 671                }
 672
 673                free(store.key);
 674                if (store.value_regex != NULL) {
 675                        regfree(store.value_regex);
 676                        free(store.value_regex);
 677                }
 678
 679                /* if nothing to unset, or too many matches, error out */
 680                if ((store.seen == 0 && value == NULL) ||
 681                                (store.seen > 1 && multi_replace == 0)) {
 682                        ret = 5;
 683                        goto out_free;
 684                }
 685
 686                fstat(in_fd, &st);
 687                contents = mmap(NULL, st.st_size, PROT_READ,
 688                        MAP_PRIVATE, in_fd, 0);
 689                close(in_fd);
 690
 691                if (store.seen == 0)
 692                        store.seen = 1;
 693
 694                for (i = 0, copy_begin = 0; i < store.seen; i++) {
 695                        if (store.offset[i] == 0) {
 696                                store.offset[i] = copy_end = st.st_size;
 697                        } else if (store.state != KEY_SEEN) {
 698                                copy_end = store.offset[i];
 699                        } else
 700                                copy_end = find_beginning_of_line(
 701                                        contents, st.st_size,
 702                                        store.offset[i]-2, &new_line);
 703
 704                        /* write the first part of the config */
 705                        if (copy_end > copy_begin) {
 706                                write(fd, contents + copy_begin,
 707                                copy_end - copy_begin);
 708                                if (new_line)
 709                                        write(fd, "\n", 1);
 710                        }
 711                        copy_begin = store.offset[i];
 712                }
 713
 714                /* write the pair (value == NULL means unset) */
 715                if (value != NULL) {
 716                        if (store.state == START)
 717                                store_write_section(fd, key);
 718                        store_write_pair(fd, key, value);
 719                }
 720
 721                /* write the rest of the config */
 722                if (copy_begin < st.st_size)
 723                        write(fd, contents + copy_begin,
 724                                st.st_size - copy_begin);
 725
 726                munmap(contents, st.st_size);
 727                unlink(config_filename);
 728        }
 729
 730        if (rename(lock_file, config_filename) < 0) {
 731                fprintf(stderr, "Could not rename the lock file?\n");
 732                ret = 4;
 733                goto out_free;
 734        }
 735
 736        ret = 0;
 737
 738out_free:
 739        if (0 <= fd)
 740                close(fd);
 741        free(config_filename);
 742        if (lock_file) {
 743                unlink(lock_file);
 744                free(lock_file);
 745        }
 746        return ret;
 747}
 748
 749