config.con commit Merge branch 'se/rebase' (3b4fd63)
   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.warnambiguousrefs")) {
 273                warn_ambiguous_refs = git_config_bool(var, value);
 274                return 0;
 275        }
 276
 277        if (!strcmp(var, "user.name")) {
 278                strncpy(git_default_name, value, sizeof(git_default_name));
 279                return 0;
 280        }
 281
 282        if (!strcmp(var, "user.email")) {
 283                strncpy(git_default_email, value, sizeof(git_default_email));
 284                return 0;
 285        }
 286
 287        if (!strcmp(var, "i18n.commitencoding")) {
 288                strncpy(git_commit_encoding, value, sizeof(git_commit_encoding));
 289                return 0;
 290        }
 291
 292        /* Add other config variables here and to Documentation/config.txt. */
 293        return 0;
 294}
 295
 296int git_config_from_file(config_fn_t fn, const char *filename)
 297{
 298        int ret;
 299        FILE *f = fopen(filename, "r");
 300
 301        ret = -1;
 302        if (f) {
 303                config_file = f;
 304                config_file_name = filename;
 305                config_linenr = 1;
 306                ret = git_parse_file(fn);
 307                fclose(f);
 308                config_file_name = NULL;
 309        }
 310        return ret;
 311}
 312
 313int git_config(config_fn_t fn)
 314{
 315        return git_config_from_file(fn, git_path("config"));
 316}
 317
 318/*
 319 * Find all the stuff for git_config_set() below.
 320 */
 321
 322#define MAX_MATCHES 512
 323
 324static struct {
 325        int baselen;
 326        char* key;
 327        int do_not_match;
 328        regex_t* value_regex;
 329        int multi_replace;
 330        off_t offset[MAX_MATCHES];
 331        enum { START, SECTION_SEEN, SECTION_END_SEEN, KEY_SEEN } state;
 332        int seen;
 333} store;
 334
 335static int matches(const char* key, const char* value)
 336{
 337        return !strcmp(key, store.key) &&
 338                (store.value_regex == NULL ||
 339                 (store.do_not_match ^
 340                  !regexec(store.value_regex, value, 0, NULL, 0)));
 341}
 342
 343static int store_aux(const char* key, const char* value)
 344{
 345        switch (store.state) {
 346        case KEY_SEEN:
 347                if (matches(key, value)) {
 348                        if (store.seen == 1 && store.multi_replace == 0) {
 349                                fprintf(stderr,
 350                                        "Warning: %s has multiple values\n",
 351                                        key);
 352                        } else if (store.seen >= MAX_MATCHES) {
 353                                fprintf(stderr, "Too many matches\n");
 354                                return 1;
 355                        }
 356
 357                        store.offset[store.seen] = ftell(config_file);
 358                        store.seen++;
 359                }
 360                break;
 361        case SECTION_SEEN:
 362                if (strncmp(key, store.key, store.baselen+1)) {
 363                        store.state = SECTION_END_SEEN;
 364                        break;
 365                } else
 366                        /* do not increment matches: this is no match */
 367                        store.offset[store.seen] = ftell(config_file);
 368                /* fallthru */
 369        case SECTION_END_SEEN:
 370        case START:
 371                if (matches(key, value)) {
 372                        store.offset[store.seen] = ftell(config_file);
 373                        store.state = KEY_SEEN;
 374                        store.seen++;
 375                } else {
 376                        if (strrchr(key, '.') - key == store.baselen &&
 377                              !strncmp(key, store.key, store.baselen)) {
 378                                        store.state = SECTION_SEEN;
 379                                        store.offset[store.seen] = ftell(config_file);
 380                        }
 381                }
 382        }
 383        return 0;
 384}
 385
 386static void store_write_section(int fd, const char* key)
 387{
 388        const char *dot = strchr(key, '.');
 389        int len1 = store.baselen, len2 = -1;
 390
 391        dot = strchr(key, '.');
 392        if (dot) {
 393                int dotlen = dot - key;
 394                if (dotlen < len1) {
 395                        len2 = len1 - dotlen - 1;
 396                        len1 = dotlen;
 397                }
 398        }
 399
 400        write(fd, "[", 1);
 401        write(fd, key, len1);
 402        if (len2 >= 0) {
 403                write(fd, " \"", 2);
 404                while (--len2 >= 0) {
 405                        unsigned char c = *++dot;
 406                        if (c == '"')
 407                                write(fd, "\\", 1);
 408                        write(fd, &c, 1);
 409                }
 410                write(fd, "\"", 1);
 411        }
 412        write(fd, "]\n", 2);
 413}
 414
 415static void store_write_pair(int fd, const char* key, const char* value)
 416{
 417        int i;
 418
 419        write(fd, "\t", 1);
 420        write(fd, key+store.baselen+1,
 421                strlen(key+store.baselen+1));
 422        write(fd, " = ", 3);
 423        for (i = 0; value[i]; i++)
 424                switch (value[i]) {
 425                case '\n': write(fd, "\\n", 2); break;
 426                case '\t': write(fd, "\\t", 2); break;
 427                case '"': case '\\': write(fd, "\\", 1);
 428                default: write(fd, value+i, 1);
 429        }
 430        write(fd, "\n", 1);
 431}
 432
 433static int find_beginning_of_line(const char* contents, int size,
 434        int offset_, int* found_bracket)
 435{
 436        int equal_offset = size, bracket_offset = size;
 437        int offset;
 438
 439        for (offset = offset_-2; offset > 0 
 440                        && contents[offset] != '\n'; offset--)
 441                switch (contents[offset]) {
 442                        case '=': equal_offset = offset; break;
 443                        case ']': bracket_offset = offset; break;
 444                }
 445        if (bracket_offset < equal_offset) {
 446                *found_bracket = 1;
 447                offset = bracket_offset+1;
 448        } else
 449                offset++;
 450
 451        return offset;
 452}
 453
 454int git_config_set(const char* key, const char* value)
 455{
 456        return git_config_set_multivar(key, value, NULL, 0);
 457}
 458
 459/*
 460 * If value==NULL, unset in (remove from) config,
 461 * if value_regex!=NULL, disregard key/value pairs where value does not match.
 462 * if multi_replace==0, nothing, or only one matching key/value is replaced,
 463 *     else all matching key/values (regardless how many) are removed,
 464 *     before the new pair is written.
 465 *
 466 * Returns 0 on success.
 467 *
 468 * This function does this:
 469 *
 470 * - it locks the config file by creating ".git/config.lock"
 471 *
 472 * - it then parses the config using store_aux() as validator to find
 473 *   the position on the key/value pair to replace. If it is to be unset,
 474 *   it must be found exactly once.
 475 *
 476 * - the config file is mmap()ed and the part before the match (if any) is
 477 *   written to the lock file, then the changed part and the rest.
 478 *
 479 * - the config file is removed and the lock file rename()d to it.
 480 *
 481 */
 482int git_config_set_multivar(const char* key, const char* value,
 483        const char* value_regex, int multi_replace)
 484{
 485        int i, dot;
 486        int fd = -1, in_fd;
 487        int ret;
 488        char* config_filename = strdup(git_path("config"));
 489        char* lock_file = strdup(git_path("config.lock"));
 490        const char* last_dot = strrchr(key, '.');
 491
 492        /*
 493         * Since "key" actually contains the section name and the real
 494         * key name separated by a dot, we have to know where the dot is.
 495         */
 496
 497        if (last_dot == NULL) {
 498                fprintf(stderr, "key does not contain a section: %s\n", key);
 499                ret = 2;
 500                goto out_free;
 501        }
 502        store.baselen = last_dot - key;
 503
 504        store.multi_replace = multi_replace;
 505
 506        /*
 507         * Validate the key and while at it, lower case it for matching.
 508         */
 509        store.key = (char*)malloc(strlen(key)+1);
 510        dot = 0;
 511        for (i = 0; key[i]; i++) {
 512                unsigned char c = key[i];
 513                if (c == '.')
 514                        dot = 1;
 515                /* Leave the extended basename untouched.. */
 516                if (!dot || i > store.baselen) {
 517                        if (!isalnum(c) || (i == store.baselen+1 && !isalpha(c))) {
 518                                fprintf(stderr, "invalid key: %s\n", key);
 519                                free(store.key);
 520                                ret = 1;
 521                                goto out_free;
 522                        }
 523                        c = tolower(c);
 524                }
 525                store.key[i] = c;
 526        }
 527        store.key[i] = 0;
 528
 529        /*
 530         * The lock_file serves a purpose in addition to locking: the new
 531         * contents of .git/config will be written into it.
 532         */
 533        fd = open(lock_file, O_WRONLY | O_CREAT | O_EXCL, 0666);
 534        if (fd < 0) {
 535                fprintf(stderr, "could not lock config file\n");
 536                free(store.key);
 537                ret = -1;
 538                goto out_free;
 539        }
 540
 541        /*
 542         * If .git/config does not exist yet, write a minimal version.
 543         */
 544        in_fd = open(config_filename, O_RDONLY);
 545        if ( in_fd < 0 ) {
 546                free(store.key);
 547
 548                if ( ENOENT != errno ) {
 549                        error("opening %s: %s", config_filename,
 550                              strerror(errno));
 551                        ret = 3; /* same as "invalid config file" */
 552                        goto out_free;
 553                }
 554                /* if nothing to unset, error out */
 555                if (value == NULL) {
 556                        ret = 5;
 557                        goto out_free;
 558                }
 559
 560                store.key = (char*)key;
 561                store_write_section(fd, key);
 562                store_write_pair(fd, key, value);
 563        } else{
 564                struct stat st;
 565                char* contents;
 566                int i, copy_begin, copy_end, new_line = 0;
 567
 568                if (value_regex == NULL)
 569                        store.value_regex = NULL;
 570                else {
 571                        if (value_regex[0] == '!') {
 572                                store.do_not_match = 1;
 573                                value_regex++;
 574                        } else
 575                                store.do_not_match = 0;
 576
 577                        store.value_regex = (regex_t*)malloc(sizeof(regex_t));
 578                        if (regcomp(store.value_regex, value_regex,
 579                                        REG_EXTENDED)) {
 580                                fprintf(stderr, "Invalid pattern: %s\n",
 581                                        value_regex);
 582                                free(store.value_regex);
 583                                ret = 6;
 584                                goto out_free;
 585                        }
 586                }
 587
 588                store.offset[0] = 0;
 589                store.state = START;
 590                store.seen = 0;
 591
 592                /*
 593                 * After this, store.offset will contain the *end* offset
 594                 * of the last match, or remain at 0 if no match was found.
 595                 * As a side effect, we make sure to transform only a valid
 596                 * existing config file.
 597                 */
 598                if (git_config(store_aux)) {
 599                        fprintf(stderr, "invalid config file\n");
 600                        free(store.key);
 601                        if (store.value_regex != NULL) {
 602                                regfree(store.value_regex);
 603                                free(store.value_regex);
 604                        }
 605                        ret = 3;
 606                        goto out_free;
 607                }
 608
 609                free(store.key);
 610                if (store.value_regex != NULL) {
 611                        regfree(store.value_regex);
 612                        free(store.value_regex);
 613                }
 614
 615                /* if nothing to unset, or too many matches, error out */
 616                if ((store.seen == 0 && value == NULL) ||
 617                                (store.seen > 1 && multi_replace == 0)) {
 618                        ret = 5;
 619                        goto out_free;
 620                }
 621
 622                fstat(in_fd, &st);
 623                contents = mmap(NULL, st.st_size, PROT_READ,
 624                        MAP_PRIVATE, in_fd, 0);
 625                close(in_fd);
 626
 627                if (store.seen == 0)
 628                        store.seen = 1;
 629
 630                for (i = 0, copy_begin = 0; i < store.seen; i++) {
 631                        if (store.offset[i] == 0) {
 632                                store.offset[i] = copy_end = st.st_size;
 633                        } else if (store.state != KEY_SEEN) {
 634                                copy_end = store.offset[i];
 635                        } else
 636                                copy_end = find_beginning_of_line(
 637                                        contents, st.st_size,
 638                                        store.offset[i]-2, &new_line);
 639
 640                        /* write the first part of the config */
 641                        if (copy_end > copy_begin) {
 642                                write(fd, contents + copy_begin,
 643                                copy_end - copy_begin);
 644                                if (new_line)
 645                                        write(fd, "\n", 1);
 646                        }
 647                        copy_begin = store.offset[i];
 648                }
 649
 650                /* write the pair (value == NULL means unset) */
 651                if (value != NULL) {
 652                        if (store.state == START)
 653                                store_write_section(fd, key);
 654                        store_write_pair(fd, key, value);
 655                }
 656
 657                /* write the rest of the config */
 658                if (copy_begin < st.st_size)
 659                        write(fd, contents + copy_begin,
 660                                st.st_size - copy_begin);
 661
 662                munmap(contents, st.st_size);
 663                unlink(config_filename);
 664        }
 665
 666        if (rename(lock_file, config_filename) < 0) {
 667                fprintf(stderr, "Could not rename the lock file?\n");
 668                ret = 4;
 669                goto out_free;
 670        }
 671
 672        ret = 0;
 673
 674out_free:
 675        if (0 <= fd)
 676                close(fd);
 677        if (config_filename)
 678                free(config_filename);
 679        if (lock_file) {
 680                unlink(lock_file);
 681                free(lock_file);
 682        }
 683        return ret;
 684}
 685
 686