config.c

   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 #include "strbuf.h"
  11 #include "quote.h"
  12
  13 typedef struct config_file {
  14         struct config_file *prev;
  15         FILE *f;
  16         const char *name;
  17         int linenr;
  18         int eof;
  19         struct strbuf value;
  20         struct strbuf var;
  21 } config_file;
  22
  23 static config_file *cf;
  24
  25 static int zlib_compression_seen;
  26
  27 #define MAX_INCLUDE_DEPTH 10
  28 static const char include_depth_advice[] =
  29 "exceeded maximum include depth (%d) while including\n"
  30 "       %s\n"
  31 "from\n"
  32 "       %s\n"
  33 "Do you have circular includes?";
  34 static int handle_path_include(const char *path, struct config_include_data *inc)
  35 {
  36         int ret = 0;
  37         struct strbuf buf = STRBUF_INIT;
  38         char *expanded = expand_user_path(path);
  39
  40         if (!expanded)
  41                 return error("Could not expand include path '%s'", path);
  42         path = expanded;
  43
  44         /*
  45          * Use an absolute path as-is, but interpret relative paths
  46          * based on the including config file.
  47          */
  48         if (!is_absolute_path(path)) {
  49                 char *slash;
  50
  51                 if (!cf || !cf->name)
  52                         return error("relative config includes must come from files");
  53
  54                 slash = find_last_dir_sep(cf->name);
  55                 if (slash)
  56                         strbuf_add(&buf, cf->name, slash - cf->name + 1);
  57                 strbuf_addstr(&buf, path);
  58                 path = buf.buf;
  59         }
  60
  61         if (!access_or_warn(path, R_OK)) {
  62                 if (++inc->depth > MAX_INCLUDE_DEPTH)
  63                         die(include_depth_advice, MAX_INCLUDE_DEPTH, path,
  64                             cf && cf->name ? cf->name : "the command line");
  65                 ret = git_config_from_file(git_config_include, path, inc);
  66                 inc->depth--;
  67         }
  68         strbuf_release(&buf);
  69         free(expanded);
  70         return ret;
  71 }
  72
  73 int git_config_include(const char *var, const char *value, void *data)
  74 {
  75         struct config_include_data *inc = data;
  76         const char *type;
  77         int ret;
  78
  79         /*
  80          * Pass along all values, including "include" directives; this makes it
  81          * possible to query information on the includes themselves.
  82          */
  83         ret = inc->fn(var, value, inc->data);
  84         if (ret < 0)
  85                 return ret;
  86
  87         type = skip_prefix(var, "include.");
  88         if (!type)
  89                 return ret;
  90
  91         if (!strcmp(type, "path"))
  92                 ret = handle_path_include(value, inc);
  93         return ret;
  94 }
  95
  96 static void lowercase(char *p)
  97 {
  98         for (; *p; p++)
  99                 *p = tolower(*p);
 100 }
 101
 102 void git_config_push_parameter(const char *text)
 103 {
 104         struct strbuf env = STRBUF_INIT;
 105         const char *old = getenv(CONFIG_DATA_ENVIRONMENT);
 106         if (old) {
 107                 strbuf_addstr(&env, old);
 108                 strbuf_addch(&env, ' ');
 109         }
 110         sq_quote_buf(&env, text);
 111         setenv(CONFIG_DATA_ENVIRONMENT, env.buf, 1);
 112         strbuf_release(&env);
 113 }
 114
 115 int git_config_parse_parameter(const char *text,
 116                                config_fn_t fn, void *data)
 117 {
 118         struct strbuf **pair;
 119         pair = strbuf_split_str(text, '=', 2);
 120         if (!pair[0])
 121                 return error("bogus config parameter: %s", text);
 122         if (pair[0]->len && pair[0]->buf[pair[0]->len - 1] == '=')
 123                 strbuf_setlen(pair[0], pair[0]->len - 1);
 124         strbuf_trim(pair[0]);
 125         if (!pair[0]->len) {
 126                 strbuf_list_free(pair);
 127                 return error("bogus config parameter: %s", text);
 128         }
 129         lowercase(pair[0]->buf);
 130         if (fn(pair[0]->buf, pair[1] ? pair[1]->buf : NULL, data) < 0) {
 131                 strbuf_list_free(pair);
 132                 return -1;
 133         }
 134         strbuf_list_free(pair);
 135         return 0;
 136 }
 137
 138 int git_config_from_parameters(config_fn_t fn, void *data)
 139 {
 140         const char *env = getenv(CONFIG_DATA_ENVIRONMENT);
 141         char *envw;
 142         const char **argv = NULL;
 143         int nr = 0, alloc = 0;
 144         int i;
 145
 146         if (!env)
 147                 return 0;
 148         /* sq_dequote will write over it */
 149         envw = xstrdup(env);
 150
 151         if (sq_dequote_to_argv(envw, &argv, &nr, &alloc) < 0) {
 152                 free(envw);
 153                 return error("bogus format in " CONFIG_DATA_ENVIRONMENT);
 154         }
 155
 156         for (i = 0; i < nr; i++) {
 157                 if (git_config_parse_parameter(argv[i], fn, data) < 0) {
 158                         free(argv);
 159                         free(envw);
 160                         return -1;
 161                 }
 162         }
 163
 164         free(argv);
 165         free(envw);
 166         return nr > 0;
 167 }
 168
 169 static int get_next_char(void)
 170 {
 171         int c;
 172         FILE *f;
 173
 174         c = '\n';
 175         if (cf && ((f = cf->f) != NULL)) {
 176                 c = fgetc(f);
 177                 if (c == '\r') {
 178                         /* DOS like systems */
 179                         c = fgetc(f);
 180                         if (c != '\n') {
 181                                 ungetc(c, f);
 182                                 c = '\r';
 183                         }
 184                 }
 185                 if (c == '\n')
 186                         cf->linenr++;
 187                 if (c == EOF) {
 188                         cf->eof = 1;
 189                         c = '\n';
 190                 }
 191         }
 192         return c;
 193 }
 194
 195 static char *parse_value(void)
 196 {
 197         int quote = 0, comment = 0, space = 0;
 198
 199         strbuf_reset(&cf->value);
 200         for (;;) {
 201                 int c = get_next_char();
 202                 if (c == '\n') {
 203                         if (quote) {
 204                                 cf->linenr--;
 205                                 return NULL;
 206                         }
 207                         return cf->value.buf;
 208                 }
 209                 if (comment)
 210                         continue;
 211                 if (isspace(c) && !quote) {
 212                         if (cf->value.len)
 213                                 space++;
 214                         continue;
 215                 }
 216                 if (!quote) {
 217                         if (c == ';' || c == '#') {
 218                                 comment = 1;
 219                                 continue;
 220                         }
 221                 }
 222                 for (; space; space--)
 223                         strbuf_addch(&cf->value, ' ');
 224                 if (c == '\\') {
 225                         c = get_next_char();
 226                         switch (c) {
 227                         case '\n':
 228                                 continue;
 229                         case 't':
 230                                 c = '\t';
 231                                 break;
 232                         case 'b':
 233                                 c = '\b';
 234                                 break;
 235                         case 'n':
 236                                 c = '\n';
 237                                 break;
 238                         /* Some characters escape as themselves */
 239                         case '\\': case '"':
 240                                 break;
 241                         /* Reject unknown escape sequences */
 242                         default:
 243                                 return NULL;
 244                         }
 245                         strbuf_addch(&cf->value, c);
 246                         continue;
 247                 }
 248                 if (c == '"') {
 249                         quote = 1-quote;
 250                         continue;
 251                 }
 252                 strbuf_addch(&cf->value, c);
 253         }
 254 }
 255
 256 static inline int iskeychar(int c)
 257 {
 258         return isalnum(c) || c == '-';
 259 }
 260
 261 static int get_value(config_fn_t fn, void *data, struct strbuf *name)
 262 {
 263         int c;
 264         char *value;
 265
 266         /* Get the full name */
 267         for (;;) {
 268                 c = get_next_char();
 269                 if (cf->eof)
 270                         break;
 271                 if (!iskeychar(c))
 272                         break;
 273                 strbuf_addch(name, tolower(c));
 274         }
 275
 276         while (c == ' ' || c == '\t')
 277                 c = get_next_char();
 278
 279         value = NULL;
 280         if (c != '\n') {
 281                 if (c != '=')
 282                         return -1;
 283                 value = parse_value();
 284                 if (!value)
 285                         return -1;
 286         }
 287         return fn(name->buf, value, data);
 288 }
 289
 290 static int get_extended_base_var(struct strbuf *name, int c)
 291 {
 292         do {
 293                 if (c == '\n')
 294                         goto error_incomplete_line;
 295                 c = get_next_char();
 296         } while (isspace(c));
 297
 298         /* We require the format to be '[base "extension"]' */
 299         if (c != '"')
 300                 return -1;
 301         strbuf_addch(name, '.');
 302
 303         for (;;) {
 304                 int c = get_next_char();
 305                 if (c == '\n')
 306                         goto error_incomplete_line;
 307                 if (c == '"')
 308                         break;
 309                 if (c == '\\') {
 310                         c = get_next_char();
 311                         if (c == '\n')
 312                                 goto error_incomplete_line;
 313                 }
 314                 strbuf_addch(name, c);
 315         }
 316
 317         /* Final ']' */
 318         if (get_next_char() != ']')
 319                 return -1;
 320         return 0;
 321 error_incomplete_line:
 322         cf->linenr--;
 323         return -1;
 324 }
 325
 326 static int get_base_var(struct strbuf *name)
 327 {
 328         for (;;) {
 329                 int c = get_next_char();
 330                 if (cf->eof)
 331                         return -1;
 332                 if (c == ']')
 333                         return 0;
 334                 if (isspace(c))
 335                         return get_extended_base_var(name, c);
 336                 if (!iskeychar(c) && c != '.')
 337                         return -1;
 338                 strbuf_addch(name, tolower(c));
 339         }
 340 }
 341
 342 static int git_parse_file(config_fn_t fn, void *data)
 343 {
 344         int comment = 0;
 345         int baselen = 0;
 346         struct strbuf *var = &cf->var;
 347
 348         /* U+FEFF Byte Order Mark in UTF8 */
 349         static const unsigned char *utf8_bom = (unsigned char *) "\xef\xbb\xbf";
 350         const unsigned char *bomptr = utf8_bom;
 351
 352         for (;;) {
 353                 int c = get_next_char();
 354                 if (bomptr && *bomptr) {
 355                         /* We are at the file beginning; skip UTF8-encoded BOM
 356                          * if present. Sane editors won't put this in on their
 357                          * own, but e.g. Windows Notepad will do it happily. */
 358                         if ((unsigned char) c == *bomptr) {
 359                                 bomptr++;
 360                                 continue;
 361                         } else {
 362                                 /* Do not tolerate partial BOM. */
 363                                 if (bomptr != utf8_bom)
 364                                         break;
 365                                 /* No BOM at file beginning. Cool. */
 366                                 bomptr = NULL;
 367                         }
 368                 }
 369                 if (c == '\n') {
 370                         if (cf->eof)
 371                                 return 0;
 372                         comment = 0;
 373                         continue;
 374                 }
 375                 if (comment || isspace(c))
 376                         continue;
 377                 if (c == '#' || c == ';') {
 378                         comment = 1;
 379                         continue;
 380                 }
 381                 if (c == '[') {
 382                         /* Reset prior to determining a new stem */
 383                         strbuf_reset(var);
 384                         if (get_base_var(var) < 0 || var->len < 1)
 385                                 break;
 386                         strbuf_addch(var, '.');
 387                         baselen = var->len;
 388                         continue;
 389                 }
 390                 if (!isalpha(c))
 391                         break;
 392                 /*
 393                  * Truncate the var name back to the section header
 394                  * stem prior to grabbing the suffix part of the name
 395                  * and the value.
 396                  */
 397                 strbuf_setlen(var, baselen);
 398                 strbuf_addch(var, tolower(c));
 399                 if (get_value(fn, data, var) < 0)
 400                         break;
 401         }
 402         die("bad config file line %d in %s", cf->linenr, cf->name);
 403 }
 404
 405 static int parse_unit_factor(const char *end, uintmax_t *val)
 406 {
 407         if (!*end)
 408                 return 1;
 409         else if (!strcasecmp(end, "k")) {
 410                 *val *= 1024;
 411                 return 1;
 412         }
 413         else if (!strcasecmp(end, "m")) {
 414                 *val *= 1024 * 1024;
 415                 return 1;
 416         }
 417         else if (!strcasecmp(end, "g")) {
 418                 *val *= 1024 * 1024 * 1024;
 419                 return 1;
 420         }
 421         return 0;
 422 }
 423
 424 static int git_parse_long(const char *value, long *ret)
 425 {
 426         if (value && *value) {
 427                 char *end;
 428                 intmax_t val;
 429                 uintmax_t uval;
 430                 uintmax_t factor = 1;
 431
 432                 errno = 0;
 433                 val = strtoimax(value, &end, 0);
 434                 if (errno == ERANGE)
 435                         return 0;
 436                 if (!parse_unit_factor(end, &factor))
 437                         return 0;
 438                 uval = abs(val);
 439                 uval *= factor;
 440                 if ((uval > maximum_signed_value_of_type(long)) ||
 441                     (abs(val) > uval))
 442                         return 0;
 443                 val *= factor;
 444                 *ret = val;
 445                 return 1;
 446         }
 447         return 0;
 448 }
 449
 450 int git_parse_ulong(const char *value, unsigned long *ret)
 451 {
 452         if (value && *value) {
 453                 char *end;
 454                 uintmax_t val;
 455                 uintmax_t oldval;
 456
 457                 errno = 0;
 458                 val = strtoumax(value, &end, 0);
 459                 if (errno == ERANGE)
 460                         return 0;
 461                 oldval = val;
 462                 if (!parse_unit_factor(end, &val))
 463                         return 0;
 464                 if ((val > maximum_unsigned_value_of_type(long)) ||
 465                     (oldval > val))
 466                         return 0;
 467                 *ret = val;
 468                 return 1;
 469         }
 470         return 0;
 471 }
 472
 473 static void die_bad_config(const char *name)
 474 {
 475         if (cf && cf->name)
 476                 die("bad config value for '%s' in %s", name, cf->name);
 477         die("bad config value for '%s'", name);
 478 }
 479
 480 int git_config_int(const char *name, const char *value)
 481 {
 482         long ret = 0;
 483         if (!git_parse_long(value, &ret))
 484                 die_bad_config(name);
 485         return ret;
 486 }
 487
 488 unsigned long git_config_ulong(const char *name, const char *value)
 489 {
 490         unsigned long ret;
 491         if (!git_parse_ulong(value, &ret))
 492                 die_bad_config(name);
 493         return ret;
 494 }
 495
 496 static int git_config_maybe_bool_text(const char *name, const char *value)
 497 {
 498         if (!value)
 499                 return 1;
 500         if (!*value)
 501                 return 0;
 502         if (!strcasecmp(value, "true")
 503             || !strcasecmp(value, "yes")
 504             || !strcasecmp(value, "on"))
 505                 return 1;
 506         if (!strcasecmp(value, "false")
 507             || !strcasecmp(value, "no")
 508             || !strcasecmp(value, "off"))
 509                 return 0;
 510         return -1;
 511 }
 512
 513 int git_config_maybe_bool(const char *name, const char *value)
 514 {
 515         long v = git_config_maybe_bool_text(name, value);
 516         if (0 <= v)
 517                 return v;
 518         if (git_parse_long(value, &v))
 519                 return !!v;
 520         return -1;
 521 }
 522
 523 int git_config_bool_or_int(const char *name, const char *value, int *is_bool)
 524 {
 525         int v = git_config_maybe_bool_text(name, value);
 526         if (0 <= v) {
 527                 *is_bool = 1;
 528                 return v;
 529         }
 530         *is_bool = 0;
 531         return git_config_int(name, value);
 532 }
 533
 534 int git_config_bool(const char *name, const char *value)
 535 {
 536         int discard;
 537         return !!git_config_bool_or_int(name, value, &discard);
 538 }
 539
 540 int git_config_string(const char **dest, const char *var, const char *value)
 541 {
 542         if (!value)
 543                 return config_error_nonbool(var);
 544         *dest = xstrdup(value);
 545         return 0;
 546 }
 547
 548 int git_config_pathname(const char **dest, const char *var, const char *value)
 549 {
 550         if (!value)
 551                 return config_error_nonbool(var);
 552         *dest = expand_user_path(value);
 553         if (!*dest)
 554                 die("Failed to expand user dir in: '%s'", value);
 555         return 0;
 556 }
 557
 558 static int git_default_core_config(const char *var, const char *value)
 559 {
 560         /* This needs a better name */
 561         if (!strcmp(var, "core.filemode")) {
 562                 trust_executable_bit = git_config_bool(var, value);
 563                 return 0;
 564         }
 565         if (!strcmp(var, "core.trustctime")) {
 566                 trust_ctime = git_config_bool(var, value);
 567                 return 0;
 568         }
 569
 570         if (!strcmp(var, "core.quotepath")) {
 571                 quote_path_fully = git_config_bool(var, value);
 572                 return 0;
 573         }
 574
 575         if (!strcmp(var, "core.symlinks")) {
 576                 has_symlinks = git_config_bool(var, value);
 577                 return 0;
 578         }
 579
 580         if (!strcmp(var, "core.ignorecase")) {
 581                 ignore_case = git_config_bool(var, value);
 582                 return 0;
 583         }
 584
 585         if (!strcmp(var, "core.attributesfile"))
 586                 return git_config_pathname(&git_attributes_file, var, value);
 587
 588         if (!strcmp(var, "core.bare")) {
 589                 is_bare_repository_cfg = git_config_bool(var, value);
 590                 return 0;
 591         }
 592
 593         if (!strcmp(var, "core.ignorestat")) {
 594                 assume_unchanged = git_config_bool(var, value);
 595                 return 0;
 596         }
 597
 598         if (!strcmp(var, "core.prefersymlinkrefs")) {
 599                 prefer_symlink_refs = git_config_bool(var, value);
 600                 return 0;
 601         }
 602
 603         if (!strcmp(var, "core.logallrefupdates")) {
 604                 log_all_ref_updates = git_config_bool(var, value);
 605                 return 0;
 606         }
 607
 608         if (!strcmp(var, "core.warnambiguousrefs")) {
 609                 warn_ambiguous_refs = git_config_bool(var, value);
 610                 return 0;
 611         }
 612
 613         if (!strcmp(var, "core.abbrev")) {
 614                 int abbrev = git_config_int(var, value);
 615                 if (abbrev < minimum_abbrev || abbrev > 40)
 616                         return -1;
 617                 default_abbrev = abbrev;
 618                 return 0;
 619         }
 620
 621         if (!strcmp(var, "core.loosecompression")) {
 622                 int level = git_config_int(var, value);
 623                 if (level == -1)
 624                         level = Z_DEFAULT_COMPRESSION;
 625                 else if (level < 0 || level > Z_BEST_COMPRESSION)
 626                         die("bad zlib compression level %d", level);
 627                 zlib_compression_level = level;
 628                 zlib_compression_seen = 1;
 629                 return 0;
 630         }
 631
 632         if (!strcmp(var, "core.compression")) {
 633                 int level = git_config_int(var, value);
 634                 if (level == -1)
 635                         level = Z_DEFAULT_COMPRESSION;
 636                 else if (level < 0 || level > Z_BEST_COMPRESSION)
 637                         die("bad zlib compression level %d", level);
 638                 core_compression_level = level;
 639                 core_compression_seen = 1;
 640                 if (!zlib_compression_seen)
 641                         zlib_compression_level = level;
 642                 return 0;
 643         }
 644
 645         if (!strcmp(var, "core.packedgitwindowsize")) {
 646                 int pgsz_x2 = getpagesize() * 2;
 647                 packed_git_window_size = git_config_ulong(var, value);
 648
 649                 /* This value must be multiple of (pagesize * 2) */
 650                 packed_git_window_size /= pgsz_x2;
 651                 if (packed_git_window_size < 1)
 652                         packed_git_window_size = 1;
 653                 packed_git_window_size *= pgsz_x2;
 654                 return 0;
 655         }
 656
 657         if (!strcmp(var, "core.bigfilethreshold")) {
 658                 big_file_threshold = git_config_ulong(var, value);
 659                 return 0;
 660         }
 661
 662         if (!strcmp(var, "core.packedgitlimit")) {
 663                 packed_git_limit = git_config_ulong(var, value);
 664                 return 0;
 665         }
 666
 667         if (!strcmp(var, "core.deltabasecachelimit")) {
 668                 delta_base_cache_limit = git_config_ulong(var, value);
 669                 return 0;
 670         }
 671
 672         if (!strcmp(var, "core.logpackaccess"))
 673                 return git_config_string(&log_pack_access, var, value);
 674
 675         if (!strcmp(var, "core.autocrlf")) {
 676                 if (value && !strcasecmp(value, "input")) {
 677                         if (core_eol == EOL_CRLF)
 678                                 return error("core.autocrlf=input conflicts with core.eol=crlf");
 679                         auto_crlf = AUTO_CRLF_INPUT;
 680                         return 0;
 681                 }
 682                 auto_crlf = git_config_bool(var, value);
 683                 return 0;
 684         }
 685
 686         if (!strcmp(var, "core.safecrlf")) {
 687                 if (value && !strcasecmp(value, "warn")) {
 688                         safe_crlf = SAFE_CRLF_WARN;
 689                         return 0;
 690                 }
 691                 safe_crlf = git_config_bool(var, value);
 692                 return 0;
 693         }
 694
 695         if (!strcmp(var, "core.eol")) {
 696                 if (value && !strcasecmp(value, "lf"))
 697                         core_eol = EOL_LF;
 698                 else if (value && !strcasecmp(value, "crlf"))
 699                         core_eol = EOL_CRLF;
 700                 else if (value && !strcasecmp(value, "native"))
 701                         core_eol = EOL_NATIVE;
 702                 else
 703                         core_eol = EOL_UNSET;
 704                 if (core_eol == EOL_CRLF && auto_crlf == AUTO_CRLF_INPUT)
 705                         return error("core.autocrlf=input conflicts with core.eol=crlf");
 706                 return 0;
 707         }
 708
 709         if (!strcmp(var, "core.notesref")) {
 710                 notes_ref_name = xstrdup(value);
 711                 return 0;
 712         }
 713
 714         if (!strcmp(var, "core.pager"))
 715                 return git_config_string(&pager_program, var, value);
 716
 717         if (!strcmp(var, "core.editor"))
 718                 return git_config_string(&editor_program, var, value);
 719
 720         if (!strcmp(var, "core.askpass"))
 721                 return git_config_string(&askpass_program, var, value);
 722
 723         if (!strcmp(var, "core.excludesfile"))
 724                 return git_config_pathname(&excludes_file, var, value);
 725
 726         if (!strcmp(var, "core.whitespace")) {
 727                 if (!value)
 728                         return config_error_nonbool(var);
 729                 whitespace_rule_cfg = parse_whitespace_rule(value);
 730                 return 0;
 731         }
 732
 733         if (!strcmp(var, "core.fsyncobjectfiles")) {
 734                 fsync_object_files = git_config_bool(var, value);
 735                 return 0;
 736         }
 737
 738         if (!strcmp(var, "core.preloadindex")) {
 739                 core_preload_index = git_config_bool(var, value);
 740                 return 0;
 741         }
 742
 743         if (!strcmp(var, "core.createobject")) {
 744                 if (!strcmp(value, "rename"))
 745                         object_creation_mode = OBJECT_CREATION_USES_RENAMES;
 746                 else if (!strcmp(value, "link"))
 747                         object_creation_mode = OBJECT_CREATION_USES_HARDLINKS;
 748                 else
 749                         die("Invalid mode for object creation: %s", value);
 750                 return 0;
 751         }
 752
 753         if (!strcmp(var, "core.sparsecheckout")) {
 754                 core_apply_sparse_checkout = git_config_bool(var, value);
 755                 return 0;
 756         }
 757
 758         if (!strcmp(var, "core.precomposeunicode")) {
 759                 precomposed_unicode = git_config_bool(var, value);
 760                 return 0;
 761         }
 762
 763         /* Add other config variables here and to Documentation/config.txt. */
 764         return 0;
 765 }
 766
 767 static int git_default_i18n_config(const char *var, const char *value)
 768 {
 769         if (!strcmp(var, "i18n.commitencoding"))
 770                 return git_config_string(&git_commit_encoding, var, value);
 771
 772         if (!strcmp(var, "i18n.logoutputencoding"))
 773                 return git_config_string(&git_log_output_encoding, var, value);
 774
 775         /* Add other config variables here and to Documentation/config.txt. */
 776         return 0;
 777 }
 778
 779 static int git_default_branch_config(const char *var, const char *value)
 780 {
 781         if (!strcmp(var, "branch.autosetupmerge")) {
 782                 if (value && !strcasecmp(value, "always")) {
 783                         git_branch_track = BRANCH_TRACK_ALWAYS;
 784                         return 0;
 785                 }
 786                 git_branch_track = git_config_bool(var, value);
 787                 return 0;
 788         }
 789         if (!strcmp(var, "branch.autosetuprebase")) {
 790                 if (!value)
 791                         return config_error_nonbool(var);
 792                 else if (!strcmp(value, "never"))
 793                         autorebase = AUTOREBASE_NEVER;
 794                 else if (!strcmp(value, "local"))
 795                         autorebase = AUTOREBASE_LOCAL;
 796                 else if (!strcmp(value, "remote"))
 797                         autorebase = AUTOREBASE_REMOTE;
 798                 else if (!strcmp(value, "always"))
 799                         autorebase = AUTOREBASE_ALWAYS;
 800                 else
 801                         return error("Malformed value for %s", var);
 802                 return 0;
 803         }
 804
 805         /* Add other config variables here and to Documentation/config.txt. */
 806         return 0;
 807 }
 808
 809 static int git_default_push_config(const char *var, const char *value)
 810 {
 811         if (!strcmp(var, "push.default")) {
 812                 if (!value)
 813                         return config_error_nonbool(var);
 814                 else if (!strcmp(value, "nothing"))
 815                         push_default = PUSH_DEFAULT_NOTHING;
 816                 else if (!strcmp(value, "matching"))
 817                         push_default = PUSH_DEFAULT_MATCHING;
 818                 else if (!strcmp(value, "simple"))
 819                         push_default = PUSH_DEFAULT_SIMPLE;
 820                 else if (!strcmp(value, "upstream"))
 821                         push_default = PUSH_DEFAULT_UPSTREAM;
 822                 else if (!strcmp(value, "tracking")) /* deprecated */
 823                         push_default = PUSH_DEFAULT_UPSTREAM;
 824                 else if (!strcmp(value, "current"))
 825                         push_default = PUSH_DEFAULT_CURRENT;
 826                 else {
 827                         error("Malformed value for %s: %s", var, value);
 828                         return error("Must be one of nothing, matching, simple, "
 829                                      "upstream or current.");
 830                 }
 831                 return 0;
 832         }
 833
 834         /* Add other config variables here and to Documentation/config.txt. */
 835         return 0;
 836 }
 837
 838 static int git_default_mailmap_config(const char *var, const char *value)
 839 {
 840         if (!strcmp(var, "mailmap.file"))
 841                 return git_config_string(&git_mailmap_file, var, value);
 842
 843         /* Add other config variables here and to Documentation/config.txt. */
 844         return 0;
 845 }
 846
 847 int git_default_config(const char *var, const char *value, void *dummy)
 848 {
 849         if (!prefixcmp(var, "core."))
 850                 return git_default_core_config(var, value);
 851
 852         if (!prefixcmp(var, "user."))
 853                 return git_ident_config(var, value, dummy);
 854
 855         if (!prefixcmp(var, "i18n."))
 856                 return git_default_i18n_config(var, value);
 857
 858         if (!prefixcmp(var, "branch."))
 859                 return git_default_branch_config(var, value);
 860
 861         if (!prefixcmp(var, "push."))
 862                 return git_default_push_config(var, value);
 863
 864         if (!prefixcmp(var, "mailmap."))
 865                 return git_default_mailmap_config(var, value);
 866
 867         if (!prefixcmp(var, "advice."))
 868                 return git_default_advice_config(var, value);
 869
 870         if (!strcmp(var, "pager.color") || !strcmp(var, "color.pager")) {
 871                 pager_use_color = git_config_bool(var,value);
 872                 return 0;
 873         }
 874
 875         if (!strcmp(var, "pack.packsizelimit")) {
 876                 pack_size_limit_cfg = git_config_ulong(var, value);
 877                 return 0;
 878         }
 879         /* Add other config variables here and to Documentation/config.txt. */
 880         return 0;
 881 }
 882
 883 int git_config_from_file(config_fn_t fn, const char *filename, void *data)
 884 {
 885         int ret;
 886         FILE *f = fopen(filename, "r");
 887
 888         ret = -1;
 889         if (f) {
 890                 config_file top;
 891
 892                 /* push config-file parsing state stack */
 893                 top.prev = cf;
 894                 top.f = f;
 895                 top.name = filename;
 896                 top.linenr = 1;
 897                 top.eof = 0;
 898                 strbuf_init(&top.value, 1024);
 899                 strbuf_init(&top.var, 1024);
 900                 cf = &top;
 901
 902                 ret = git_parse_file(fn, data);
 903
 904                 /* pop config-file parsing state stack */
 905                 strbuf_release(&top.value);
 906                 strbuf_release(&top.var);
 907                 cf = top.prev;
 908
 909                 fclose(f);
 910         }
 911         return ret;
 912 }
 913
 914 const char *git_etc_gitconfig(void)
 915 {
 916         static const char *system_wide;
 917         if (!system_wide)
 918                 system_wide = system_path(ETC_GITCONFIG);
 919         return system_wide;
 920 }
 921
 922 int git_env_bool(const char *k, int def)
 923 {
 924         const char *v = getenv(k);
 925         return v ? git_config_bool(k, v) : def;
 926 }
 927
 928 int git_config_system(void)
 929 {
 930         return !git_env_bool("GIT_CONFIG_NOSYSTEM", 0);
 931 }
 932
 933 int git_config_early(config_fn_t fn, void *data, const char *repo_config)
 934 {
 935         int ret = 0, found = 0;
 936         char *xdg_config = NULL;
 937         char *user_config = NULL;
 938
 939         home_config_paths(&user_config, &xdg_config, "config");
 940
 941         if (git_config_system() && !access_or_warn(git_etc_gitconfig(), R_OK)) {
 942                 ret += git_config_from_file(fn, git_etc_gitconfig(),
 943                                             data);
 944                 found += 1;
 945         }
 946
 947         if (xdg_config && !access_or_warn(xdg_config, R_OK)) {
 948                 ret += git_config_from_file(fn, xdg_config, data);
 949                 found += 1;
 950         }
 951
 952         if (user_config && !access_or_warn(user_config, R_OK)) {
 953                 ret += git_config_from_file(fn, user_config, data);
 954                 found += 1;
 955         }
 956
 957         if (repo_config && !access_or_warn(repo_config, R_OK)) {
 958                 ret += git_config_from_file(fn, repo_config, data);
 959                 found += 1;
 960         }
 961
 962         switch (git_config_from_parameters(fn, data)) {
 963         case -1: /* error */
 964                 die("unable to parse command-line config");
 965                 break;
 966         case 0: /* found nothing */
 967                 break;
 968         default: /* found at least one item */
 969                 found++;
 970                 break;
 971         }
 972
 973         free(xdg_config);
 974         free(user_config);
 975         return ret == 0 ? found : ret;
 976 }
 977
 978 int git_config_with_options(config_fn_t fn, void *data,
 979                             const char *filename, int respect_includes)
 980 {
 981         char *repo_config = NULL;
 982         int ret;
 983         struct config_include_data inc = CONFIG_INCLUDE_INIT;
 984
 985         if (respect_includes) {
 986                 inc.fn = fn;
 987                 inc.data = data;
 988                 fn = git_config_include;
 989                 data = &inc;
 990         }
 991
 992         /*
 993          * If we have a specific filename, use it. Otherwise, follow the
 994          * regular lookup sequence.
 995          */
 996         if (filename)
 997                 return git_config_from_file(fn, filename, data);
 998
 999         repo_config = git_pathdup("config");
1000         ret = git_config_early(fn, data, repo_config);
1001         if (repo_config)
1002                 free(repo_config);
1003         return ret;
1004 }
1005
1006 int git_config(config_fn_t fn, void *data)
1007 {
1008         return git_config_with_options(fn, data, NULL, 1);
1009 }
1010
1011 /*
1012  * Find all the stuff for git_config_set() below.
1013  */
1014
1015 #define MAX_MATCHES 512
1016
1017 static struct {
1018         int baselen;
1019         char *key;
1020         int do_not_match;
1021         regex_t *value_regex;
1022         int multi_replace;
1023         size_t offset[MAX_MATCHES];
1024         enum { START, SECTION_SEEN, SECTION_END_SEEN, KEY_SEEN } state;
1025         int seen;
1026 } store;
1027
1028 static int matches(const char *key, const char *value)
1029 {
1030         return !strcmp(key, store.key) &&
1031                 (store.value_regex == NULL ||
1032                  (store.do_not_match ^
1033                   !regexec(store.value_regex, value, 0, NULL, 0)));
1034 }
1035
1036 static int store_aux(const char *key, const char *value, void *cb)
1037 {
1038         const char *ep;
1039         size_t section_len;
1040         FILE *f = cf->f;
1041
1042         switch (store.state) {
1043         case KEY_SEEN:
1044                 if (matches(key, value)) {
1045                         if (store.seen == 1 && store.multi_replace == 0) {
1046                                 warning("%s has multiple values", key);
1047                         } else if (store.seen >= MAX_MATCHES) {
1048                                 error("too many matches for %s", key);
1049                                 return 1;
1050                         }
1051
1052                         store.offset[store.seen] = ftell(f);
1053                         store.seen++;
1054                 }
1055                 break;
1056         case SECTION_SEEN:
1057                 /*
1058                  * What we are looking for is in store.key (both
1059                  * section and var), and its section part is baselen
1060                  * long.  We found key (again, both section and var).
1061                  * We would want to know if this key is in the same
1062                  * section as what we are looking for.  We already
1063                  * know we are in the same section as what should
1064                  * hold store.key.
1065                  */
1066                 ep = strrchr(key, '.');
1067                 section_len = ep - key;
1068
1069                 if ((section_len != store.baselen) ||
1070                     memcmp(key, store.key, section_len+1)) {
1071                         store.state = SECTION_END_SEEN;
1072                         break;
1073                 }
1074
1075                 /*
1076                  * Do not increment matches: this is no match, but we
1077                  * just made sure we are in the desired section.
1078                  */
1079                 store.offset[store.seen] = ftell(f);
1080                 /* fallthru */
1081         case SECTION_END_SEEN:
1082         case START:
1083                 if (matches(key, value)) {
1084                         store.offset[store.seen] = ftell(f);
1085                         store.state = KEY_SEEN;
1086                         store.seen++;
1087                 } else {
1088                         if (strrchr(key, '.') - key == store.baselen &&
1089                               !strncmp(key, store.key, store.baselen)) {
1090                                         store.state = SECTION_SEEN;
1091                                         store.offset[store.seen] = ftell(f);
1092                         }
1093                 }
1094         }
1095         return 0;
1096 }
1097
1098 static int write_error(const char *filename)
1099 {
1100         error("failed to write new configuration file %s", filename);
1101
1102         /* Same error code as "failed to rename". */
1103         return 4;
1104 }
1105
1106 static int store_write_section(int fd, const char *key)
1107 {
1108         const char *dot;
1109         int i, success;
1110         struct strbuf sb = STRBUF_INIT;
1111
1112         dot = memchr(key, '.', store.baselen);
1113         if (dot) {
1114                 strbuf_addf(&sb, "[%.*s \"", (int)(dot - key), key);
1115                 for (i = dot - key + 1; i < store.baselen; i++) {
1116                         if (key[i] == '"' || key[i] == '\\')
1117                                 strbuf_addch(&sb, '\\');
1118                         strbuf_addch(&sb, key[i]);
1119                 }
1120                 strbuf_addstr(&sb, "\"]\n");
1121         } else {
1122                 strbuf_addf(&sb, "[%.*s]\n", store.baselen, key);
1123         }
1124
1125         success = write_in_full(fd, sb.buf, sb.len) == sb.len;
1126         strbuf_release(&sb);
1127
1128         return success;
1129 }
1130
1131 static int store_write_pair(int fd, const char *key, const char *value)
1132 {
1133         int i, success;
1134         int length = strlen(key + store.baselen + 1);
1135         const char *quote = "";
1136         struct strbuf sb = STRBUF_INIT;
1137
1138         /*
1139          * Check to see if the value needs to be surrounded with a dq pair.
1140          * Note that problematic characters are always backslash-quoted; this
1141          * check is about not losing leading or trailing SP and strings that
1142          * follow beginning-of-comment characters (i.e. ';' and '#') by the
1143          * configuration parser.
1144          */
1145         if (value[0] == ' ')
1146                 quote = "\"";
1147         for (i = 0; value[i]; i++)
1148                 if (value[i] == ';' || value[i] == '#')
1149                         quote = "\"";
1150         if (i && value[i - 1] == ' ')
1151                 quote = "\"";
1152
1153         strbuf_addf(&sb, "\t%.*s = %s",
1154                     length, key + store.baselen + 1, quote);
1155
1156         for (i = 0; value[i]; i++)
1157                 switch (value[i]) {
1158                 case '\n':
1159                         strbuf_addstr(&sb, "\\n");
1160                         break;
1161                 case '\t':
1162                         strbuf_addstr(&sb, "\\t");
1163                         break;
1164                 case '"':
1165                 case '\\':
1166                         strbuf_addch(&sb, '\\');
1167                 default:
1168                         strbuf_addch(&sb, value[i]);
1169                         break;
1170                 }
1171         strbuf_addf(&sb, "%s\n", quote);
1172
1173         success = write_in_full(fd, sb.buf, sb.len) == sb.len;
1174         strbuf_release(&sb);
1175
1176         return success;
1177 }
1178
1179 static ssize_t find_beginning_of_line(const char *contents, size_t size,
1180         size_t offset_, int *found_bracket)
1181 {
1182         size_t equal_offset = size, bracket_offset = size;
1183         ssize_t offset;
1184
1185 contline:
1186         for (offset = offset_-2; offset > 0
1187                         && contents[offset] != '\n'; offset--)
1188                 switch (contents[offset]) {
1189                         case '=': equal_offset = offset; break;
1190                         case ']': bracket_offset = offset; break;
1191                 }
1192         if (offset > 0 && contents[offset-1] == '\\') {
1193                 offset_ = offset;
1194                 goto contline;
1195         }
1196         if (bracket_offset < equal_offset) {
1197                 *found_bracket = 1;
1198                 offset = bracket_offset+1;
1199         } else
1200                 offset++;
1201
1202         return offset;
1203 }
1204
1205 int git_config_set_in_file(const char *config_filename,
1206                         const char *key, const char *value)
1207 {
1208         return git_config_set_multivar_in_file(config_filename, key, value, NULL, 0);
1209 }
1210
1211 int git_config_set(const char *key, const char *value)
1212 {
1213         return git_config_set_multivar(key, value, NULL, 0);
1214 }
1215
1216 /*
1217  * Auxiliary function to sanity-check and split the key into the section
1218  * identifier and variable name.
1219  *
1220  * Returns 0 on success, -1 when there is an invalid character in the key and
1221  * -2 if there is no section name in the key.
1222  *
1223  * store_key - pointer to char* which will hold a copy of the key with
1224  *             lowercase section and variable name
1225  * baselen - pointer to int which will hold the length of the
1226  *           section + subsection part, can be NULL
1227  */
1228 int git_config_parse_key(const char *key, char **store_key, int *baselen_)
1229 {
1230         int i, dot, baselen;
1231         const char *last_dot = strrchr(key, '.');
1232
1233         /*
1234          * Since "key" actually contains the section name and the real
1235          * key name separated by a dot, we have to know where the dot is.
1236          */
1237
1238         if (last_dot == NULL || last_dot == key) {
1239                 error("key does not contain a section: %s", key);
1240                 return -CONFIG_NO_SECTION_OR_NAME;
1241         }
1242
1243         if (!last_dot[1]) {
1244                 error("key does not contain variable name: %s", key);
1245                 return -CONFIG_NO_SECTION_OR_NAME;
1246         }
1247
1248         baselen = last_dot - key;
1249         if (baselen_)
1250                 *baselen_ = baselen;
1251
1252         /*
1253          * Validate the key and while at it, lower case it for matching.
1254          */
1255         *store_key = xmalloc(strlen(key) + 1);
1256
1257         dot = 0;
1258         for (i = 0; key[i]; i++) {
1259                 unsigned char c = key[i];
1260                 if (c == '.')
1261                         dot = 1;
1262                 /* Leave the extended basename untouched.. */
1263                 if (!dot || i > baselen) {
1264                         if (!iskeychar(c) ||
1265                             (i == baselen + 1 && !isalpha(c))) {
1266                                 error("invalid key: %s", key);
1267                                 goto out_free_ret_1;
1268                         }
1269                         c = tolower(c);
1270                 } else if (c == '\n') {
1271                         error("invalid key (newline): %s", key);
1272                         goto out_free_ret_1;
1273                 }
1274                 (*store_key)[i] = c;
1275         }
1276         (*store_key)[i] = 0;
1277
1278         return 0;
1279
1280 out_free_ret_1:
1281         free(*store_key);
1282         return -CONFIG_INVALID_KEY;
1283 }
1284
1285 /*
1286  * If value==NULL, unset in (remove from) config,
1287  * if value_regex!=NULL, disregard key/value pairs where value does not match.
1288  * if multi_replace==0, nothing, or only one matching key/value is replaced,
1289  *     else all matching key/values (regardless how many) are removed,
1290  *     before the new pair is written.
1291  *
1292  * Returns 0 on success.
1293  *
1294  * This function does this:
1295  *
1296  * - it locks the config file by creating ".git/config.lock"
1297  *
1298  * - it then parses the config using store_aux() as validator to find
1299  *   the position on the key/value pair to replace. If it is to be unset,
1300  *   it must be found exactly once.
1301  *
1302  * - the config file is mmap()ed and the part before the match (if any) is
1303  *   written to the lock file, then the changed part and the rest.
1304  *
1305  * - the config file is removed and the lock file rename()d to it.
1306  *
1307  */
1308 int git_config_set_multivar_in_file(const char *config_filename,
1309                                 const char *key, const char *value,
1310                                 const char *value_regex, int multi_replace)
1311 {
1312         int fd = -1, in_fd;
1313         int ret;
1314         struct lock_file *lock = NULL;
1315         char *filename_buf = NULL;
1316
1317         /* parse-key returns negative; flip the sign to feed exit(3) */
1318         ret = 0 - git_config_parse_key(key, &store.key, &store.baselen);
1319         if (ret)
1320                 goto out_free;
1321
1322         store.multi_replace = multi_replace;
1323
1324         if (!config_filename)
1325                 config_filename = filename_buf = git_pathdup("config");
1326
1327         /*
1328          * The lock serves a purpose in addition to locking: the new
1329          * contents of .git/config will be written into it.
1330          */
1331         lock = xcalloc(sizeof(struct lock_file), 1);
1332         fd = hold_lock_file_for_update(lock, config_filename, 0);
1333         if (fd < 0) {
1334                 error("could not lock config file %s: %s", config_filename, strerror(errno));
1335                 free(store.key);
1336                 ret = CONFIG_NO_LOCK;
1337                 goto out_free;
1338         }
1339
1340         /*
1341          * If .git/config does not exist yet, write a minimal version.
1342          */
1343         in_fd = open(config_filename, O_RDONLY);
1344         if ( in_fd < 0 ) {
1345                 free(store.key);
1346
1347                 if ( ENOENT != errno ) {
1348                         error("opening %s: %s", config_filename,
1349                               strerror(errno));
1350                         ret = CONFIG_INVALID_FILE; /* same as "invalid config file" */
1351                         goto out_free;
1352                 }
1353                 /* if nothing to unset, error out */
1354                 if (value == NULL) {
1355                         ret = CONFIG_NOTHING_SET;
1356                         goto out_free;
1357                 }
1358
1359                 store.key = (char *)key;
1360                 if (!store_write_section(fd, key) ||
1361                     !store_write_pair(fd, key, value))
1362                         goto write_err_out;
1363         } else {
1364                 struct stat st;
1365                 char *contents;
1366                 size_t contents_sz, copy_begin, copy_end;
1367                 int i, new_line = 0;
1368
1369                 if (value_regex == NULL)
1370                         store.value_regex = NULL;
1371                 else {
1372                         if (value_regex[0] == '!') {
1373                                 store.do_not_match = 1;
1374                                 value_regex++;
1375                         } else
1376                                 store.do_not_match = 0;
1377
1378                         store.value_regex = (regex_t*)xmalloc(sizeof(regex_t));
1379                         if (regcomp(store.value_regex, value_regex,
1380                                         REG_EXTENDED)) {
1381                                 error("invalid pattern: %s", value_regex);
1382                                 free(store.value_regex);
1383                                 ret = CONFIG_INVALID_PATTERN;
1384                                 goto out_free;
1385                         }
1386                 }
1387
1388                 store.offset[0] = 0;
1389                 store.state = START;
1390                 store.seen = 0;
1391
1392                 /*
1393                  * After this, store.offset will contain the *end* offset
1394                  * of the last match, or remain at 0 if no match was found.
1395                  * As a side effect, we make sure to transform only a valid
1396                  * existing config file.
1397                  */
1398                 if (git_config_from_file(store_aux, config_filename, NULL)) {
1399                         error("invalid config file %s", config_filename);
1400                         free(store.key);
1401                         if (store.value_regex != NULL) {
1402                                 regfree(store.value_regex);
1403                                 free(store.value_regex);
1404                         }
1405                         ret = CONFIG_INVALID_FILE;
1406                         goto out_free;
1407                 }
1408
1409                 free(store.key);
1410                 if (store.value_regex != NULL) {
1411                         regfree(store.value_regex);
1412                         free(store.value_regex);
1413                 }
1414
1415                 /* if nothing to unset, or too many matches, error out */
1416                 if ((store.seen == 0 && value == NULL) ||
1417                                 (store.seen > 1 && multi_replace == 0)) {
1418                         ret = CONFIG_NOTHING_SET;
1419                         goto out_free;
1420                 }
1421
1422                 fstat(in_fd, &st);
1423                 contents_sz = xsize_t(st.st_size);
1424                 contents = xmmap(NULL, contents_sz, PROT_READ,
1425                         MAP_PRIVATE, in_fd, 0);
1426                 close(in_fd);
1427
1428                 if (store.seen == 0)
1429                         store.seen = 1;
1430
1431                 for (i = 0, copy_begin = 0; i < store.seen; i++) {
1432                         if (store.offset[i] == 0) {
1433                                 store.offset[i] = copy_end = contents_sz;
1434                         } else if (store.state != KEY_SEEN) {
1435                                 copy_end = store.offset[i];
1436                         } else
1437                                 copy_end = find_beginning_of_line(
1438                                         contents, contents_sz,
1439                                         store.offset[i]-2, &new_line);
1440
1441                         if (copy_end > 0 && contents[copy_end-1] != '\n')
1442                                 new_line = 1;
1443
1444                         /* write the first part of the config */
1445                         if (copy_end > copy_begin) {
1446                                 if (write_in_full(fd, contents + copy_begin,
1447                                                   copy_end - copy_begin) <
1448                                     copy_end - copy_begin)
1449                                         goto write_err_out;
1450                                 if (new_line &&
1451                                     write_str_in_full(fd, "\n") != 1)
1452                                         goto write_err_out;
1453                         }
1454                         copy_begin = store.offset[i];
1455                 }
1456
1457                 /* write the pair (value == NULL means unset) */
1458                 if (value != NULL) {
1459                         if (store.state == START) {
1460                                 if (!store_write_section(fd, key))
1461                                         goto write_err_out;
1462                         }
1463                         if (!store_write_pair(fd, key, value))
1464                                 goto write_err_out;
1465                 }
1466
1467                 /* write the rest of the config */
1468                 if (copy_begin < contents_sz)
1469                         if (write_in_full(fd, contents + copy_begin,
1470                                           contents_sz - copy_begin) <
1471                             contents_sz - copy_begin)
1472                                 goto write_err_out;
1473
1474                 munmap(contents, contents_sz);
1475         }
1476
1477         if (commit_lock_file(lock) < 0) {
1478                 error("could not commit config file %s", config_filename);
1479                 ret = CONFIG_NO_WRITE;
1480                 goto out_free;
1481         }
1482
1483         /*
1484          * lock is committed, so don't try to roll it back below.
1485          * NOTE: Since lockfile.c keeps a linked list of all created
1486          * lock_file structures, it isn't safe to free(lock).  It's
1487          * better to just leave it hanging around.
1488          */
1489         lock = NULL;
1490         ret = 0;
1491
1492 out_free:
1493         if (lock)
1494                 rollback_lock_file(lock);
1495         free(filename_buf);
1496         return ret;
1497
1498 write_err_out:
1499         ret = write_error(lock->filename);
1500         goto out_free;
1501
1502 }
1503
1504 int git_config_set_multivar(const char *key, const char *value,
1505                         const char *value_regex, int multi_replace)
1506 {
1507         return git_config_set_multivar_in_file(NULL, key, value, value_regex,
1508                                                multi_replace);
1509 }
1510
1511 static int section_name_match (const char *buf, const char *name)
1512 {
1513         int i = 0, j = 0, dot = 0;
1514         if (buf[i] != '[')
1515                 return 0;
1516         for (i = 1; buf[i] && buf[i] != ']'; i++) {
1517                 if (!dot && isspace(buf[i])) {
1518                         dot = 1;
1519                         if (name[j++] != '.')
1520                                 break;
1521                         for (i++; isspace(buf[i]); i++)
1522                                 ; /* do nothing */
1523                         if (buf[i] != '"')
1524                                 break;
1525                         continue;
1526                 }
1527                 if (buf[i] == '\\' && dot)
1528                         i++;
1529                 else if (buf[i] == '"' && dot) {
1530                         for (i++; isspace(buf[i]); i++)
1531                                 ; /* do_nothing */
1532                         break;
1533                 }
1534                 if (buf[i] != name[j++])
1535                         break;
1536         }
1537         if (buf[i] == ']' && name[j] == 0) {
1538                 /*
1539                  * We match, now just find the right length offset by
1540                  * gobbling up any whitespace after it, as well
1541                  */
1542                 i++;
1543                 for (; buf[i] && isspace(buf[i]); i++)
1544                         ; /* do nothing */
1545                 return i;
1546         }
1547         return 0;
1548 }
1549
1550 static int section_name_is_ok(const char *name)
1551 {
1552         /* Empty section names are bogus. */
1553         if (!*name)
1554                 return 0;
1555
1556         /*
1557          * Before a dot, we must be alphanumeric or dash. After the first dot,
1558          * anything goes, so we can stop checking.
1559          */
1560         for (; *name && *name != '.'; name++)
1561                 if (*name != '-' && !isalnum(*name))
1562                         return 0;
1563         return 1;
1564 }
1565
1566 /* if new_name == NULL, the section is removed instead */
1567 int git_config_rename_section_in_file(const char *config_filename,
1568                                       const char *old_name, const char *new_name)
1569 {
1570         int ret = 0, remove = 0;
1571         char *filename_buf = NULL;
1572         struct lock_file *lock;
1573         int out_fd;
1574         char buf[1024];
1575         FILE *config_file;
1576
1577         if (new_name && !section_name_is_ok(new_name)) {
1578                 ret = error("invalid section name: %s", new_name);
1579                 goto out;
1580         }
1581
1582         if (!config_filename)
1583                 config_filename = filename_buf = git_pathdup("config");
1584
1585         lock = xcalloc(sizeof(struct lock_file), 1);
1586         out_fd = hold_lock_file_for_update(lock, config_filename, 0);
1587         if (out_fd < 0) {
1588                 ret = error("could not lock config file %s", config_filename);
1589                 goto out;
1590         }
1591
1592         if (!(config_file = fopen(config_filename, "rb"))) {
1593                 /* no config file means nothing to rename, no error */
1594                 goto unlock_and_out;
1595         }
1596
1597         while (fgets(buf, sizeof(buf), config_file)) {
1598                 int i;
1599                 int length;
1600                 char *output = buf;
1601                 for (i = 0; buf[i] && isspace(buf[i]); i++)
1602                         ; /* do nothing */
1603                 if (buf[i] == '[') {
1604                         /* it's a section */
1605                         int offset = section_name_match(&buf[i], old_name);
1606                         if (offset > 0) {
1607                                 ret++;
1608                                 if (new_name == NULL) {
1609                                         remove = 1;
1610                                         continue;
1611                                 }
1612                                 store.baselen = strlen(new_name);
1613                                 if (!store_write_section(out_fd, new_name)) {
1614                                         ret = write_error(lock->filename);
1615                                         goto out;
1616                                 }
1617                                 /*
1618                                  * We wrote out the new section, with
1619                                  * a newline, now skip the old
1620                                  * section's length
1621                                  */
1622                                 output += offset + i;
1623                                 if (strlen(output) > 0) {
1624                                         /*
1625                                          * More content means there's
1626                                          * a declaration to put on the
1627                                          * next line; indent with a
1628                                          * tab
1629                                          */
1630                                         output -= 1;
1631                                         output[0] = '\t';
1632                                 }
1633                         }
1634                         remove = 0;
1635                 }
1636                 if (remove)
1637                         continue;
1638                 length = strlen(output);
1639                 if (write_in_full(out_fd, output, length) != length) {
1640                         ret = write_error(lock->filename);
1641                         goto out;
1642                 }
1643         }
1644         fclose(config_file);
1645 unlock_and_out:
1646         if (commit_lock_file(lock) < 0)
1647                 ret = error("could not commit config file %s", config_filename);
1648 out:
1649         free(filename_buf);
1650         return ret;
1651 }
1652
1653 int git_config_rename_section(const char *old_name, const char *new_name)
1654 {
1655         return git_config_rename_section_in_file(NULL, old_name, new_name);
1656 }
1657
1658 /*
1659  * Call this to report error for your variable that should not
1660  * get a boolean value (i.e. "[my] var" means "true").
1661  */
1662 int config_error_nonbool(const char *var)
1663 {
1664         return error("Missing value for '%s'", var);
1665 }