config.con commit move get_merge_bases() to core lib. (7c6f8aa)
   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 int get_value(config_fn_t fn, char *name, unsigned int len)
 107{
 108        int c;
 109        char *value;
 110
 111        /* Get the full name */
 112        for (;;) {
 113                c = get_next_char();
 114                if (c == EOF)
 115                        break;
 116                if (!isalnum(c))
 117                        break;
 118                name[len++] = tolower(c);
 119                if (len >= MAXNAME)
 120                        return -1;
 121        }
 122        name[len] = 0;
 123        while (c == ' ' || c == '\t')
 124                c = get_next_char();
 125
 126        value = NULL;
 127        if (c != '\n') {
 128                if (c != '=')
 129                        return -1;
 130                value = parse_value();
 131                if (!value)
 132                        return -1;
 133        }
 134        return fn(name, value);
 135}
 136
 137static int get_extended_base_var(char *name, int baselen, int c)
 138{
 139        do {
 140                if (c == '\n')
 141                        return -1;
 142                c = get_next_char();
 143        } while (isspace(c));
 144
 145        /* We require the format to be '[base "extension"]' */
 146        if (c != '"')
 147                return -1;
 148        name[baselen++] = '.';
 149
 150        for (;;) {
 151                int c = get_next_char();
 152                if (c == '\n')
 153                        return -1;
 154                if (c == '"')
 155                        break;
 156                if (c == '\\') {
 157                        c = get_next_char();
 158                        if (c == '\n')
 159                                return -1;
 160                }
 161                name[baselen++] = c;
 162                if (baselen > MAXNAME / 2)
 163                        return -1;
 164        }
 165
 166        /* Final ']' */
 167        if (get_next_char() != ']')
 168                return -1;
 169        return baselen;
 170}
 171
 172static int get_base_var(char *name)
 173{
 174        int baselen = 0;
 175
 176        for (;;) {
 177                int c = get_next_char();
 178                if (c == EOF)
 179                        return -1;
 180                if (c == ']')
 181                        return baselen;
 182                if (isspace(c))
 183                        return get_extended_base_var(name, baselen, c);
 184                if (!isalnum(c) && c != '.')
 185                        return -1;
 186                if (baselen > MAXNAME / 2)
 187                        return -1;
 188                name[baselen++] = tolower(c);
 189        }
 190}
 191
 192static int git_parse_file(config_fn_t fn)
 193{
 194        int comment = 0;
 195        int baselen = 0;
 196        static char var[MAXNAME];
 197
 198        for (;;) {
 199                int c = get_next_char();
 200                if (c == '\n') {
 201                        /* EOF? */
 202                        if (!config_file)
 203                                return 0;
 204                        comment = 0;
 205                        continue;
 206                }
 207                if (comment || isspace(c))
 208                        continue;
 209                if (c == '#' || c == ';') {
 210                        comment = 1;
 211                        continue;
 212                }
 213                if (c == '[') {
 214                        baselen = get_base_var(var);
 215                        if (baselen <= 0)
 216                                break;
 217                        var[baselen++] = '.';
 218                        var[baselen] = 0;
 219                        continue;
 220                }
 221                if (!isalpha(c))
 222                        break;
 223                var[baselen] = tolower(c);
 224                if (get_value(fn, var, baselen+1) < 0)
 225                        break;
 226        }
 227        die("bad config file line %d in %s", config_linenr, config_file_name);
 228}
 229
 230int git_config_int(const char *name, const char *value)
 231{
 232        if (value && *value) {
 233                char *end;
 234                int val = strtol(value, &end, 0);
 235                if (!*end)
 236                        return val;
 237        }
 238        die("bad config value for '%s' in %s", name, config_file_name);
 239}
 240
 241int git_config_bool(const char *name, const char *value)
 242{
 243        if (!value)
 244                return 1;
 245        if (!*value)
 246                return 0;
 247        if (!strcasecmp(value, "true"))
 248                return 1;
 249        if (!strcasecmp(value, "false"))
 250                return 0;
 251        return git_config_int(name, value) != 0;
 252}
 253
 254int git_default_config(const char *var, const char *value)
 255{
 256        /* This needs a better name */
 257        if (!strcmp(var, "core.filemode")) {
 258                trust_executable_bit = git_config_bool(var, value);
 259                return 0;
 260        }
 261
 262        if (!strcmp(var, "core.ignorestat")) {
 263                assume_unchanged = git_config_bool(var, value);
 264                return 0;
 265        }
 266
 267        if (!strcmp(var, "core.prefersymlinkrefs")) {
 268                prefer_symlink_refs = git_config_bool(var, value);
 269                return 0;
 270        }
 271
 272        if (!strcmp(var, "core.logallrefupdates")) {
 273                log_all_ref_updates = git_config_bool(var, value);
 274                return 0;
 275        }
 276
 277        if (!strcmp(var, "core.warnambiguousrefs")) {
 278                warn_ambiguous_refs = git_config_bool(var, value);
 279                return 0;
 280        }
 281
 282        if (!strcmp(var, "user.name")) {
 283                strlcpy(git_default_name, value, sizeof(git_default_name));
 284                return 0;
 285        }
 286
 287        if (!strcmp(var, "user.email")) {
 288                strlcpy(git_default_email, value, sizeof(git_default_email));
 289                return 0;
 290        }
 291
 292        if (!strcmp(var, "i18n.commitencoding")) {
 293                strlcpy(git_commit_encoding, value, sizeof(git_commit_encoding));
 294                return 0;
 295        }
 296
 297        /* Add other config variables here and to Documentation/config.txt. */
 298        return 0;
 299}
 300
 301int git_config_from_file(config_fn_t fn, const char *filename)
 302{
 303        int ret;
 304        FILE *f = fopen(filename, "r");
 305
 306        ret = -1;
 307        if (f) {
 308                config_file = f;
 309                config_file_name = filename;
 310                config_linenr = 1;
 311                ret = git_parse_file(fn);
 312                fclose(f);
 313                config_file_name = NULL;
 314        }
 315        return ret;
 316}
 317
 318int git_config(config_fn_t fn)
 319{
 320        int ret = 0;
 321        char *repo_config = NULL;
 322        const char *home = NULL, *filename;
 323
 324        /* $GIT_CONFIG makes git read _only_ the given config file,
 325         * $GIT_CONFIG_LOCAL will make it process it in addition to the
 326         * global config file, the same way it would the per-repository
 327         * config file otherwise. */
 328        filename = getenv("GIT_CONFIG");
 329        if (!filename) {
 330                home = getenv("HOME");
 331                filename = getenv("GIT_CONFIG_LOCAL");
 332                if (!filename)
 333                        filename = repo_config = strdup(git_path("config"));
 334        }
 335
 336        if (home) {
 337                char *user_config = strdup(mkpath("%s/.gitconfig", home));
 338                if (!access(user_config, R_OK))
 339                        ret = git_config_from_file(fn, user_config);
 340                free(user_config);
 341        }
 342
 343        ret += git_config_from_file(fn, filename);
 344        if (repo_config)
 345                free(repo_config);
 346        return ret;
 347}
 348
 349/*
 350 * Find all the stuff for git_config_set() below.
 351 */
 352
 353#define MAX_MATCHES 512
 354
 355static struct {
 356        int baselen;
 357        char* key;
 358        int do_not_match;
 359        regex_t* value_regex;
 360        int multi_replace;
 361        off_t offset[MAX_MATCHES];
 362        enum { START, SECTION_SEEN, SECTION_END_SEEN, KEY_SEEN } state;
 363        int seen;
 364} store;
 365
 366static int matches(const char* key, const char* value)
 367{
 368        return !strcmp(key, store.key) &&
 369                (store.value_regex == NULL ||
 370                 (store.do_not_match ^
 371                  !regexec(store.value_regex, value, 0, NULL, 0)));
 372}
 373
 374static int store_aux(const char* key, const char* value)
 375{
 376        switch (store.state) {
 377        case KEY_SEEN:
 378                if (matches(key, value)) {
 379                        if (store.seen == 1 && store.multi_replace == 0) {
 380                                fprintf(stderr,
 381                                        "Warning: %s has multiple values\n",
 382                                        key);
 383                        } else if (store.seen >= MAX_MATCHES) {
 384                                fprintf(stderr, "Too many matches\n");
 385                                return 1;
 386                        }
 387
 388                        store.offset[store.seen] = ftell(config_file);
 389                        store.seen++;
 390                }
 391                break;
 392        case SECTION_SEEN:
 393                if (strncmp(key, store.key, store.baselen+1)) {
 394                        store.state = SECTION_END_SEEN;
 395                        break;
 396                } else
 397                        /* do not increment matches: this is no match */
 398                        store.offset[store.seen] = ftell(config_file);
 399                /* fallthru */
 400        case SECTION_END_SEEN:
 401        case START:
 402                if (matches(key, value)) {
 403                        store.offset[store.seen] = ftell(config_file);
 404                        store.state = KEY_SEEN;
 405                        store.seen++;
 406                } else {
 407                        if (strrchr(key, '.') - key == store.baselen &&
 408                              !strncmp(key, store.key, store.baselen)) {
 409                                        store.state = SECTION_SEEN;
 410                                        store.offset[store.seen] = ftell(config_file);
 411                        }
 412                }
 413        }
 414        return 0;
 415}
 416
 417static void store_write_section(int fd, const char* key)
 418{
 419        const char *dot = strchr(key, '.');
 420        int len1 = store.baselen, len2 = -1;
 421
 422        dot = strchr(key, '.');
 423        if (dot) {
 424                int dotlen = dot - key;
 425                if (dotlen < len1) {
 426                        len2 = len1 - dotlen - 1;
 427                        len1 = dotlen;
 428                }
 429        }
 430
 431        write(fd, "[", 1);
 432        write(fd, key, len1);
 433        if (len2 >= 0) {
 434                write(fd, " \"", 2);
 435                while (--len2 >= 0) {
 436                        unsigned char c = *++dot;
 437                        if (c == '"')
 438                                write(fd, "\\", 1);
 439                        write(fd, &c, 1);
 440                }
 441                write(fd, "\"", 1);
 442        }
 443        write(fd, "]\n", 2);
 444}
 445
 446static void store_write_pair(int fd, const char* key, const char* value)
 447{
 448        int i;
 449
 450        write(fd, "\t", 1);
 451        write(fd, key+store.baselen+1,
 452                strlen(key+store.baselen+1));
 453        write(fd, " = ", 3);
 454        for (i = 0; value[i]; i++)
 455                switch (value[i]) {
 456                case '\n': write(fd, "\\n", 2); break;
 457                case '\t': write(fd, "\\t", 2); break;
 458                case '"': case '\\': write(fd, "\\", 1);
 459                default: write(fd, value+i, 1);
 460        }
 461        write(fd, "\n", 1);
 462}
 463
 464static int find_beginning_of_line(const char* contents, int size,
 465        int offset_, int* found_bracket)
 466{
 467        int equal_offset = size, bracket_offset = size;
 468        int offset;
 469
 470        for (offset = offset_-2; offset > 0 
 471                        && contents[offset] != '\n'; offset--)
 472                switch (contents[offset]) {
 473                        case '=': equal_offset = offset; break;
 474                        case ']': bracket_offset = offset; break;
 475                }
 476        if (bracket_offset < equal_offset) {
 477                *found_bracket = 1;
 478                offset = bracket_offset+1;
 479        } else
 480                offset++;
 481
 482        return offset;
 483}
 484
 485int git_config_set(const char* key, const char* value)
 486{
 487        return git_config_set_multivar(key, value, NULL, 0);
 488}
 489
 490/*
 491 * If value==NULL, unset in (remove from) config,
 492 * if value_regex!=NULL, disregard key/value pairs where value does not match.
 493 * if multi_replace==0, nothing, or only one matching key/value is replaced,
 494 *     else all matching key/values (regardless how many) are removed,
 495 *     before the new pair is written.
 496 *
 497 * Returns 0 on success.
 498 *
 499 * This function does this:
 500 *
 501 * - it locks the config file by creating ".git/config.lock"
 502 *
 503 * - it then parses the config using store_aux() as validator to find
 504 *   the position on the key/value pair to replace. If it is to be unset,
 505 *   it must be found exactly once.
 506 *
 507 * - the config file is mmap()ed and the part before the match (if any) is
 508 *   written to the lock file, then the changed part and the rest.
 509 *
 510 * - the config file is removed and the lock file rename()d to it.
 511 *
 512 */
 513int git_config_set_multivar(const char* key, const char* value,
 514        const char* value_regex, int multi_replace)
 515{
 516        int i, dot;
 517        int fd = -1, in_fd;
 518        int ret;
 519        char* config_filename;
 520        char* lock_file;
 521        const char* last_dot = strrchr(key, '.');
 522
 523        config_filename = getenv("GIT_CONFIG");
 524        if (!config_filename) {
 525                config_filename = getenv("GIT_CONFIG_LOCAL");
 526                if (!config_filename)
 527                        config_filename  = git_path("config");
 528        }
 529        config_filename = strdup(config_filename);
 530        lock_file = strdup(mkpath("%s.lock", config_filename));
 531
 532        /*
 533         * Since "key" actually contains the section name and the real
 534         * key name separated by a dot, we have to know where the dot is.
 535         */
 536
 537        if (last_dot == NULL) {
 538                fprintf(stderr, "key does not contain a section: %s\n", key);
 539                ret = 2;
 540                goto out_free;
 541        }
 542        store.baselen = last_dot - key;
 543
 544        store.multi_replace = multi_replace;
 545
 546        /*
 547         * Validate the key and while at it, lower case it for matching.
 548         */
 549        store.key = (char*)malloc(strlen(key)+1);
 550        dot = 0;
 551        for (i = 0; key[i]; i++) {
 552                unsigned char c = key[i];
 553                if (c == '.')
 554                        dot = 1;
 555                /* Leave the extended basename untouched.. */
 556                if (!dot || i > store.baselen) {
 557                        if (!isalnum(c) || (i == store.baselen+1 && !isalpha(c))) {
 558                                fprintf(stderr, "invalid key: %s\n", key);
 559                                free(store.key);
 560                                ret = 1;
 561                                goto out_free;
 562                        }
 563                        c = tolower(c);
 564                }
 565                store.key[i] = c;
 566        }
 567        store.key[i] = 0;
 568
 569        /*
 570         * The lock_file serves a purpose in addition to locking: the new
 571         * contents of .git/config will be written into it.
 572         */
 573        fd = open(lock_file, O_WRONLY | O_CREAT | O_EXCL, 0666);
 574        if (fd < 0 || adjust_shared_perm(lock_file)) {
 575                fprintf(stderr, "could not lock config file\n");
 576                free(store.key);
 577                ret = -1;
 578                goto out_free;
 579        }
 580
 581        /*
 582         * If .git/config does not exist yet, write a minimal version.
 583         */
 584        in_fd = open(config_filename, O_RDONLY);
 585        if ( in_fd < 0 ) {
 586                free(store.key);
 587
 588                if ( ENOENT != errno ) {
 589                        error("opening %s: %s", config_filename,
 590                              strerror(errno));
 591                        ret = 3; /* same as "invalid config file" */
 592                        goto out_free;
 593                }
 594                /* if nothing to unset, error out */
 595                if (value == NULL) {
 596                        ret = 5;
 597                        goto out_free;
 598                }
 599
 600                store.key = (char*)key;
 601                store_write_section(fd, key);
 602                store_write_pair(fd, key, value);
 603        } else{
 604                struct stat st;
 605                char* contents;
 606                int i, copy_begin, copy_end, new_line = 0;
 607
 608                if (value_regex == NULL)
 609                        store.value_regex = NULL;
 610                else {
 611                        if (value_regex[0] == '!') {
 612                                store.do_not_match = 1;
 613                                value_regex++;
 614                        } else
 615                                store.do_not_match = 0;
 616
 617                        store.value_regex = (regex_t*)malloc(sizeof(regex_t));
 618                        if (regcomp(store.value_regex, value_regex,
 619                                        REG_EXTENDED)) {
 620                                fprintf(stderr, "Invalid pattern: %s\n",
 621                                        value_regex);
 622                                free(store.value_regex);
 623                                ret = 6;
 624                                goto out_free;
 625                        }
 626                }
 627
 628                store.offset[0] = 0;
 629                store.state = START;
 630                store.seen = 0;
 631
 632                /*
 633                 * After this, store.offset will contain the *end* offset
 634                 * of the last match, or remain at 0 if no match was found.
 635                 * As a side effect, we make sure to transform only a valid
 636                 * existing config file.
 637                 */
 638                if (git_config_from_file(store_aux, config_filename)) {
 639                        fprintf(stderr, "invalid config file\n");
 640                        free(store.key);
 641                        if (store.value_regex != NULL) {
 642                                regfree(store.value_regex);
 643                                free(store.value_regex);
 644                        }
 645                        ret = 3;
 646                        goto out_free;
 647                }
 648
 649                free(store.key);
 650                if (store.value_regex != NULL) {
 651                        regfree(store.value_regex);
 652                        free(store.value_regex);
 653                }
 654
 655                /* if nothing to unset, or too many matches, error out */
 656                if ((store.seen == 0 && value == NULL) ||
 657                                (store.seen > 1 && multi_replace == 0)) {
 658                        ret = 5;
 659                        goto out_free;
 660                }
 661
 662                fstat(in_fd, &st);
 663                contents = mmap(NULL, st.st_size, PROT_READ,
 664                        MAP_PRIVATE, in_fd, 0);
 665                close(in_fd);
 666
 667                if (store.seen == 0)
 668                        store.seen = 1;
 669
 670                for (i = 0, copy_begin = 0; i < store.seen; i++) {
 671                        if (store.offset[i] == 0) {
 672                                store.offset[i] = copy_end = st.st_size;
 673                        } else if (store.state != KEY_SEEN) {
 674                                copy_end = store.offset[i];
 675                        } else
 676                                copy_end = find_beginning_of_line(
 677                                        contents, st.st_size,
 678                                        store.offset[i]-2, &new_line);
 679
 680                        /* write the first part of the config */
 681                        if (copy_end > copy_begin) {
 682                                write(fd, contents + copy_begin,
 683                                copy_end - copy_begin);
 684                                if (new_line)
 685                                        write(fd, "\n", 1);
 686                        }
 687                        copy_begin = store.offset[i];
 688                }
 689
 690                /* write the pair (value == NULL means unset) */
 691                if (value != NULL) {
 692                        if (store.state == START)
 693                                store_write_section(fd, key);
 694                        store_write_pair(fd, key, value);
 695                }
 696
 697                /* write the rest of the config */
 698                if (copy_begin < st.st_size)
 699                        write(fd, contents + copy_begin,
 700                                st.st_size - copy_begin);
 701
 702                munmap(contents, st.st_size);
 703                unlink(config_filename);
 704        }
 705
 706        if (rename(lock_file, config_filename) < 0) {
 707                fprintf(stderr, "Could not rename the lock file?\n");
 708                ret = 4;
 709                goto out_free;
 710        }
 711
 712        ret = 0;
 713
 714out_free:
 715        if (0 <= fd)
 716                close(fd);
 717        if (config_filename)
 718                free(config_filename);
 719        if (lock_file) {
 720                unlink(lock_file);
 721                free(lock_file);
 722        }
 723        return ret;
 724}
 725
 726