src/attr_file.c

   1 #include "common.h"
   2 #include "repository.h"
   3 #include "filebuf.h"
   4 #include "attr_file.h"
   5 #include "attrcache.h"
   6 #include "git2/blob.h"
   7 #include "git2/tree.h"
   8 #include "index.h"
   9 #include <ctype.h>
  10
  11 static void attr_file_free(git_attr_file *file)
  12 {
  13         bool unlock = !git_mutex_lock(&file->lock);
  14         git_attr_file__clear_rules(file, false);
  15         git_pool_clear(&file->pool);
  16         if (unlock)
  17                 git_mutex_unlock(&file->lock);
  18         git_mutex_free(&file->lock);
  19
  20         git__memzero(file, sizeof(*file));
  21         git__free(file);
  22 }
  23
  24 int git_attr_file__new(
  25         git_attr_file **out,
  26         git_attr_file_entry *entry,
  27         git_attr_file_source source)
  28 {
  29         git_attr_file *attrs = git__calloc(1, sizeof(git_attr_file));
  30         GITERR_CHECK_ALLOC(attrs);
  31
  32         if (git_mutex_init(&attrs->lock) < 0) {
  33                 giterr_set(GITERR_OS, "Failed to initialize lock");
  34                 git__free(attrs);
  35                 return -1;
  36         }
  37
  38         if (git_pool_init(&attrs->pool, 1, 0) < 0) {
  39                 attr_file_free(attrs);
  40                 return -1;
  41         }
  42
  43         GIT_REFCOUNT_INC(attrs);
  44         attrs->entry  = entry;
  45         attrs->source = source;
  46         *out = attrs;
  47         return 0;
  48 }
  49
  50 int git_attr_file__clear_rules(git_attr_file *file, bool need_lock)
  51 {
  52         unsigned int i;
  53         git_attr_rule *rule;
  54
  55         if (need_lock && git_mutex_lock(&file->lock) < 0) {
  56                 giterr_set(GITERR_OS, "Failed to lock attribute file");
  57                 return -1;
  58         }
  59
  60         git_vector_foreach(&file->rules, i, rule)
  61                 git_attr_rule__free(rule);
  62         git_vector_free(&file->rules);
  63
  64         if (need_lock)
  65                 git_mutex_unlock(&file->lock);
  66
  67         return 0;
  68 }
  69
  70 void git_attr_file__free(git_attr_file *file)
  71 {
  72         if (!file)
  73                 return;
  74         GIT_REFCOUNT_DEC(file, attr_file_free);
  75 }
  76
  77 static int attr_file_oid_from_index(
  78         git_oid *oid, git_repository *repo, const char *path)
  79 {
  80         int error;
  81         git_index *idx;
  82         size_t pos;
  83         const git_index_entry *entry;
  84
  85         if ((error = git_repository_index__weakptr(&idx, repo)) < 0 ||
  86                 (error = git_index__find_pos(&pos, idx, path, 0, 0)) < 0)
  87                 return error;
  88
  89         if (!(entry = git_index_get_byindex(idx, pos)))
  90                 return GIT_ENOTFOUND;
  91
  92         *oid = entry->id;
  93         return 0;
  94 }
  95
  96 int git_attr_file__load(
  97         git_attr_file **out,
  98         git_repository *repo,
  99         git_attr_session *attr_session,
 100         git_attr_file_entry *entry,
 101         git_attr_file_source source,
 102         git_attr_file_parser parser)
 103 {
 104         int error = 0;
 105         git_blob *blob = NULL;
 106         git_buf content = GIT_BUF_INIT;
 107         git_attr_file *file;
 108         struct stat st;
 109         bool nonexistent = false;
 110
 111         *out = NULL;
 112
 113         switch (source) {
 114         case GIT_ATTR_FILE__IN_MEMORY:
 115                 /* in-memory attribute file doesn't need data */
 116                 break;
 117         case GIT_ATTR_FILE__FROM_INDEX: {
 118                 git_oid id;
 119
 120                 if ((error = attr_file_oid_from_index(&id, repo, entry->path)) < 0 ||
 121                         (error = git_blob_lookup(&blob, repo, &id)) < 0)
 122                         return error;
 123
 124                 /* Do not assume that data straight from the ODB is NULL-terminated;
 125                  * copy the contents of a file to a buffer to work on */
 126                 git_buf_put(&content, git_blob_rawcontent(blob), git_blob_rawsize(blob));
 127                 break;
 128         }
 129         case GIT_ATTR_FILE__FROM_FILE: {
 130                 int fd;
 131
 132                 /* For open or read errors, pretend that we got ENOTFOUND. */
 133                 /* TODO: issue warning when warning API is available */
 134
 135                 if (p_stat(entry->fullpath, &st) < 0 ||
 136                         S_ISDIR(st.st_mode) ||
 137                         (fd = git_futils_open_ro(entry->fullpath)) < 0 ||
 138                         (error = git_futils_readbuffer_fd(&content, fd, (size_t)st.st_size)) < 0)
 139                         nonexistent = true;
 140                 else
 141                         p_close(fd);
 142
 143                 break;
 144         }
 145         default:
 146                 giterr_set(GITERR_INVALID, "Unknown file source %d", source);
 147                 return -1;
 148         }
 149
 150         if ((error = git_attr_file__new(&file, entry, source)) < 0)
 151                 goto cleanup;
 152
 153         /* store the key of the attr_reader; don't bother with cache
 154          * invalidation during the same attr reader session.
 155          */
 156         if (attr_session)
 157                 file->session_key = attr_session->key;
 158
 159         if (parser && (error = parser(repo, file, git_buf_cstr(&content))) < 0) {
 160                 git_attr_file__free(file);
 161                 goto cleanup;
 162         }
 163
 164         /* write cache breakers */
 165         if (nonexistent)
 166                 file->nonexistent = 1;
 167         else if (source == GIT_ATTR_FILE__FROM_INDEX)
 168                 git_oid_cpy(&file->cache_data.oid, git_blob_id(blob));
 169         else if (source == GIT_ATTR_FILE__FROM_FILE)
 170                 git_futils_filestamp_set_from_stat(&file->cache_data.stamp, &st);
 171         /* else always cacheable */
 172
 173         *out = file;
 174
 175 cleanup:
 176         git_blob_free(blob);
 177         git_buf_free(&content);
 178
 179         return error;
 180 }
 181
 182 int git_attr_file__out_of_date(
 183         git_repository *repo,
 184         git_attr_session *attr_session,
 185         git_attr_file *file)
 186 {
 187         if (!file)
 188                 return 1;
 189
 190         /* we are never out of date if we just created this data in the same
 191          * attr_session; otherwise, nonexistent files must be invalidated
 192          */
 193         if (attr_session && attr_session->key == file->session_key)
 194                 return 0;
 195         else if (file->nonexistent)
 196                 return 1;
 197
 198         switch (file->source) {
 199         case GIT_ATTR_FILE__IN_MEMORY:
 200                 return 0;
 201
 202         case GIT_ATTR_FILE__FROM_FILE:
 203                 return git_futils_filestamp_check(
 204                         &file->cache_data.stamp, file->entry->fullpath);
 205
 206         case GIT_ATTR_FILE__FROM_INDEX: {
 207                 int error;
 208                 git_oid id;
 209
 210                 if ((error = attr_file_oid_from_index(
 211                                 &id, repo, file->entry->path)) < 0)
 212                         return error;
 213
 214                 return (git_oid__cmp(&file->cache_data.oid, &id) != 0);
 215         }
 216
 217         default:
 218                 giterr_set(GITERR_INVALID, "Invalid file type %d", file->source);
 219                 return -1;
 220         }
 221 }
 222
 223 static int sort_by_hash_and_name(const void *a_raw, const void *b_raw);
 224 static void git_attr_rule__clear(git_attr_rule *rule);
 225 static bool parse_optimized_patterns(
 226         git_attr_fnmatch *spec,
 227         git_pool *pool,
 228         const char *pattern);
 229
 230 int git_attr_file__parse_buffer(
 231         git_repository *repo, git_attr_file *attrs, const char *data)
 232 {
 233         int error = 0;
 234         const char *scan = data, *context = NULL;
 235         git_attr_rule *rule = NULL;
 236
 237         /* if subdir file path, convert context for file paths */
 238         if (attrs->entry &&
 239                 git_path_root(attrs->entry->path) < 0 &&
 240                 !git__suffixcmp(attrs->entry->path, "/" GIT_ATTR_FILE))
 241                 context = attrs->entry->path;
 242
 243         if (git_mutex_lock(&attrs->lock) < 0) {
 244                 giterr_set(GITERR_OS, "Failed to lock attribute file");
 245                 return -1;
 246         }
 247
 248         while (!error && *scan) {
 249                 /* allocate rule if needed */
 250                 if (!rule && !(rule = git__calloc(1, sizeof(*rule)))) {
 251                         error = -1;
 252                         break;
 253                 }
 254
 255                 rule->match.flags =
 256                         GIT_ATTR_FNMATCH_ALLOWNEG | GIT_ATTR_FNMATCH_ALLOWMACRO;
 257
 258                 /* parse the next "pattern attr attr attr" line */
 259                 if (!(error = git_attr_fnmatch__parse(
 260                                 &rule->match, &attrs->pool, context, &scan)) &&
 261                         !(error = git_attr_assignment__parse(
 262                                 repo, &attrs->pool, &rule->assigns, &scan)))
 263                 {
 264                         if (rule->match.flags & GIT_ATTR_FNMATCH_MACRO)
 265                                 /* TODO: warning if macro found in file below repo root */
 266                                 error = git_attr_cache__insert_macro(repo, rule);
 267                         else
 268                                 error = git_vector_insert(&attrs->rules, rule);
 269                 }
 270
 271                 /* if the rule wasn't a pattern, on to the next */
 272                 if (error < 0) {
 273                         git_attr_rule__clear(rule); /* reset rule contents */
 274                         if (error == GIT_ENOTFOUND)
 275                                 error = 0;
 276                 } else {
 277                         rule = NULL; /* vector now "owns" the rule */
 278                 }
 279         }
 280
 281         git_mutex_unlock(&attrs->lock);
 282         git_attr_rule__free(rule);
 283
 284         return error;
 285 }
 286
 287 uint32_t git_attr_file__name_hash(const char *name)
 288 {
 289         uint32_t h = 5381;
 290         int c;
 291         assert(name);
 292         while ((c = (int)*name++) != 0)
 293                 h = ((h << 5) + h) + c;
 294         return h;
 295 }
 296
 297 int git_attr_file__lookup_one(
 298         git_attr_file *file,
 299         git_attr_path *path,
 300         const char *attr,
 301         const char **value)
 302 {
 303         size_t i;
 304         git_attr_name name;
 305         git_attr_rule *rule;
 306
 307         *value = NULL;
 308
 309         name.name = attr;
 310         name.name_hash = git_attr_file__name_hash(attr);
 311
 312         git_attr_file__foreach_matching_rule(file, path, i, rule) {
 313                 size_t pos;
 314
 315                 if (!git_vector_bsearch(&pos, &rule->assigns, &name)) {
 316                         *value = ((git_attr_assignment *)
 317                                           git_vector_get(&rule->assigns, pos))->value;
 318                         break;
 319                 }
 320         }
 321
 322         return 0;
 323 }
 324
 325 int git_attr_file__load_standalone(git_attr_file **out, const char *path)
 326 {
 327         int error;
 328         git_attr_file *file;
 329         git_buf content = GIT_BUF_INIT;
 330
 331         error = git_attr_file__new(&file, NULL, GIT_ATTR_FILE__FROM_FILE);
 332         if (error < 0)
 333                 return error;
 334
 335         error = git_attr_cache__alloc_file_entry(
 336                 &file->entry, NULL, path, &file->pool);
 337         if (error < 0) {
 338                 git_attr_file__free(file);
 339                 return error;
 340         }
 341         /* because the cache entry is allocated from the file's own pool, we
 342          * don't have to free it - freeing file+pool will free cache entry, too.
 343          */
 344
 345         if (!(error = git_futils_readbuffer(&content, path))) {
 346                 error = git_attr_file__parse_buffer(NULL, file, content.ptr);
 347                 git_buf_free(&content);
 348         }
 349
 350         if (error < 0)
 351                 git_attr_file__free(file);
 352         else
 353                 *out = file;
 354
 355         return error;
 356 }
 357
 358 bool git_attr_fnmatch__match(
 359         git_attr_fnmatch *match,
 360         git_attr_path *path)
 361 {
 362         const char *filename;
 363         int flags = 0;
 364
 365         /*
 366          * If the rule was generated in a subdirectory, we must only
 367          * use it for paths inside that directory. We can thus return
 368          * a non-match if the prefixes don't match.
 369          */
 370         if (match->containing_dir) {
 371                 if (match->flags & GIT_ATTR_FNMATCH_ICASE) {
 372                         if (git__strncasecmp(path->path, match->containing_dir, match->containing_dir_length))
 373                                 return 0;
 374                 } else {
 375                         if (git__prefixcmp(path->path, match->containing_dir))
 376                                 return 0;
 377                 }
 378         }
 379
 380         if (match->flags & GIT_ATTR_FNMATCH_ICASE)
 381                 flags |= FNM_CASEFOLD;
 382         if (match->flags & GIT_ATTR_FNMATCH_LEADINGDIR)
 383                 flags |= FNM_LEADING_DIR;
 384
 385         if (match->flags & GIT_ATTR_FNMATCH_FULLPATH) {
 386                 filename = path->path;
 387                 flags |= FNM_PATHNAME;
 388         } else {
 389                 filename = path->basename;
 390
 391                 if (path->is_dir)
 392                         flags |= FNM_LEADING_DIR;
 393         }
 394
 395         if ((match->flags & GIT_ATTR_FNMATCH_DIRECTORY) && !path->is_dir) {
 396                 int matchval;
 397
 398                 /* for attribute checks or root ignore checks, fail match */
 399                 if (!(match->flags & GIT_ATTR_FNMATCH_IGNORE) ||
 400                         path->basename == path->path)
 401                         return false;
 402
 403                 /* for ignore checks, use container of current item for check */
 404                 path->basename[-1] = '\0';
 405                 flags |= FNM_LEADING_DIR;
 406                 matchval = p_fnmatch(match->pattern, path->path, flags);
 407                 path->basename[-1] = '/';
 408                 return (matchval != FNM_NOMATCH);
 409         }
 410
 411         /* if path is a directory prefix of a negated pattern, then match */
 412         if ((match->flags & GIT_ATTR_FNMATCH_NEGATIVE) && path->is_dir) {
 413                 size_t pathlen = strlen(path->path);
 414                 bool prefixed = (pathlen <= match->length) &&
 415                         ((match->flags & GIT_ATTR_FNMATCH_ICASE) ?
 416                          !strncasecmp(match->pattern, path->path, pathlen) :
 417                          !strncmp(match->pattern, path->path, pathlen));
 418
 419                 if (prefixed && git_path_at_end_of_segment(&match->pattern[pathlen]))
 420                         return true;
 421         }
 422
 423         return (p_fnmatch(match->pattern, filename, flags) != FNM_NOMATCH);
 424 }
 425
 426 bool git_attr_rule__match(
 427         git_attr_rule *rule,
 428         git_attr_path *path)
 429 {
 430         bool matched = git_attr_fnmatch__match(&rule->match, path);
 431
 432         if (rule->match.flags & GIT_ATTR_FNMATCH_NEGATIVE)
 433                 matched = !matched;
 434
 435         return matched;
 436 }
 437
 438 git_attr_assignment *git_attr_rule__lookup_assignment(
 439         git_attr_rule *rule, const char *name)
 440 {
 441         size_t pos;
 442         git_attr_name key;
 443         key.name = name;
 444         key.name_hash = git_attr_file__name_hash(name);
 445
 446         if (git_vector_bsearch(&pos, &rule->assigns, &key))
 447                 return NULL;
 448
 449         return git_vector_get(&rule->assigns, pos);
 450 }
 451
 452 int git_attr_path__init(
 453         git_attr_path *info, const char *path, const char *base)
 454 {
 455         ssize_t root;
 456
 457         /* build full path as best we can */
 458         git_buf_init(&info->full, 0);
 459
 460         if (git_path_join_unrooted(&info->full, path, base, &root) < 0)
 461                 return -1;
 462
 463         info->path = info->full.ptr + root;
 464
 465         /* remove trailing slashes */
 466         while (info->full.size > 0) {
 467                 if (info->full.ptr[info->full.size - 1] != '/')
 468                         break;
 469                 info->full.size--;
 470         }
 471         info->full.ptr[info->full.size] = '\0';
 472
 473         /* skip leading slashes in path */
 474         while (*info->path == '/')
 475                 info->path++;
 476
 477         /* find trailing basename component */
 478         info->basename = strrchr(info->path, '/');
 479         if (info->basename)
 480                 info->basename++;
 481         if (!info->basename || !*info->basename)
 482                 info->basename = info->path;
 483
 484         info->is_dir = (int)git_path_isdir(info->full.ptr);
 485
 486         return 0;
 487 }
 488
 489 void git_attr_path__free(git_attr_path *info)
 490 {
 491         git_buf_free(&info->full);
 492         info->path = NULL;
 493         info->basename = NULL;
 494 }
 495
 496 /*
 497  * From gitattributes(5):
 498  *
 499  * Patterns have the following format:
 500  *
 501  * - A blank line matches no files, so it can serve as a separator for
 502  *   readability.
 503  *
 504  * - A line starting with # serves as a comment.
 505  *
 506  * - An optional prefix ! which negates the pattern; any matching file
 507  *   excluded by a previous pattern will become included again. If a negated
 508  *   pattern matches, this will override lower precedence patterns sources.
 509  *
 510  * - If the pattern ends with a slash, it is removed for the purpose of the
 511  *   following description, but it would only find a match with a directory. In
 512  *   other words, foo/ will match a directory foo and paths underneath it, but
 513  *   will not match a regular file or a symbolic link foo (this is consistent
 514  *   with the way how pathspec works in general in git).
 515  *
 516  * - If the pattern does not contain a slash /, git treats it as a shell glob
 517  *   pattern and checks for a match against the pathname without leading
 518  *   directories.
 519  *
 520  * - Otherwise, git treats the pattern as a shell glob suitable for consumption
 521  *   by fnmatch(3) with the FNM_PATHNAME flag: wildcards in the pattern will
 522  *   not match a / in the pathname. For example, "Documentation/\*.html" matches
 523  *   "Documentation/git.html" but not "Documentation/ppc/ppc.html". A leading
 524  *   slash matches the beginning of the pathname; for example, "/\*.c" matches
 525  *   "cat-file.c" but not "mozilla-sha1/sha1.c".
 526  */
 527
 528 /*
 529  * This will return 0 if the spec was filled out,
 530  * GIT_ENOTFOUND if the fnmatch does not require matching, or
 531  * another error code there was an actual problem.
 532  */
 533 int git_attr_fnmatch__parse(
 534         git_attr_fnmatch *spec,
 535         git_pool *pool,
 536         const char *context,
 537         const char **base)
 538 {
 539         const char *pattern, *scan;
 540         int slash_count, allow_space;
 541
 542         assert(spec && base && *base);
 543
 544         if (parse_optimized_patterns(spec, pool, *base))
 545                 return 0;
 546
 547         spec->flags = (spec->flags & GIT_ATTR_FNMATCH__INCOMING);
 548         allow_space = ((spec->flags & GIT_ATTR_FNMATCH_ALLOWSPACE) != 0);
 549
 550         pattern = *base;
 551
 552         while (git__isspace(*pattern)) pattern++;
 553         if (!*pattern || *pattern == '#') {
 554                 *base = git__next_line(pattern);
 555                 return GIT_ENOTFOUND;
 556         }
 557
 558         if (*pattern == '[' && (spec->flags & GIT_ATTR_FNMATCH_ALLOWMACRO) != 0) {
 559                 if (strncmp(pattern, "[attr]", 6) == 0) {
 560                         spec->flags = spec->flags | GIT_ATTR_FNMATCH_MACRO;
 561                         pattern += 6;
 562                 }
 563                 /* else a character range like [a-e]* which is accepted */
 564         }
 565
 566         if (*pattern == '!' && (spec->flags & GIT_ATTR_FNMATCH_ALLOWNEG) != 0) {
 567                 spec->flags = spec->flags |
 568                         GIT_ATTR_FNMATCH_NEGATIVE | GIT_ATTR_FNMATCH_LEADINGDIR;
 569                 pattern++;
 570         }
 571
 572         slash_count = 0;
 573         for (scan = pattern; *scan != '\0'; ++scan) {
 574                 /* scan until (non-escaped) white space */
 575                 if (git__isspace(*scan) && *(scan - 1) != '\\') {
 576                         if (!allow_space || (*scan != ' ' && *scan != '\t' && *scan != '\r'))
 577                                 break;
 578                 }
 579
 580                 if (*scan == '/') {
 581                         spec->flags = spec->flags | GIT_ATTR_FNMATCH_FULLPATH;
 582                         slash_count++;
 583                         if (pattern == scan)
 584                                 pattern++;
 585                 }
 586                 /* remember if we see an unescaped wildcard in pattern */
 587                 else if (git__iswildcard(*scan) &&
 588                         (scan == pattern || (*(scan - 1) != '\\')))
 589                         spec->flags = spec->flags | GIT_ATTR_FNMATCH_HASWILD;
 590         }
 591
 592         *base = scan;
 593
 594         if ((spec->length = scan - pattern) == 0)
 595                 return GIT_ENOTFOUND;
 596
 597         /*
 598          * Remove one trailing \r in case this is a CRLF delimited
 599          * file, in the case of Icon\r\r\n, we still leave the first
 600          * \r there to match against.
 601          */
 602         if (pattern[spec->length - 1] == '\r')
 603                 if (--spec->length == 0)
 604                         return GIT_ENOTFOUND;
 605
 606         if (pattern[spec->length - 1] == '/') {
 607                 spec->length--;
 608                 spec->flags = spec->flags | GIT_ATTR_FNMATCH_DIRECTORY;
 609                 if (--slash_count <= 0)
 610                         spec->flags = spec->flags & ~GIT_ATTR_FNMATCH_FULLPATH;
 611         }
 612         if ((spec->flags & GIT_ATTR_FNMATCH_NOLEADINGDIR) == 0 &&
 613                 spec->length >= 2 &&
 614                 pattern[spec->length - 1] == '*' &&
 615                 pattern[spec->length - 2] == '/') {
 616                 spec->length -= 2;
 617                 spec->flags = spec->flags | GIT_ATTR_FNMATCH_LEADINGDIR;
 618                 /* leave FULLPATH match on, however */
 619         }
 620
 621         if (context) {
 622                 char *slash = strchr(context, '/');
 623                 size_t len;
 624                 if (slash) {
 625                         /* include the slash for easier matching */
 626                         len = slash - context + 1;
 627                         spec->containing_dir = git_pool_strndup(pool, context, len);
 628                         spec->containing_dir_length = len;
 629                 }
 630         }
 631
 632         if ((spec->flags & GIT_ATTR_FNMATCH_FULLPATH) != 0 &&
 633                 context != NULL && git_path_root(pattern) < 0)
 634         {
 635                 /* use context path minus the trailing filename */
 636                 char *slash = strrchr(context, '/');
 637                 size_t contextlen = slash ? slash - context + 1 : 0;
 638
 639                 /* given an unrooted fullpath match from a file inside a repo,
 640                  * prefix the pattern with the relative directory of the source file
 641                  */
 642                 spec->pattern = git_pool_malloc(
 643                         pool, (uint32_t)(contextlen + spec->length + 1));
 644                 if (spec->pattern) {
 645                         memcpy(spec->pattern, context, contextlen);
 646                         memcpy(spec->pattern + contextlen, pattern, spec->length);
 647                         spec->length += contextlen;
 648                         spec->pattern[spec->length] = '\0';
 649                 }
 650         } else {
 651                 spec->pattern = git_pool_strndup(pool, pattern, spec->length);
 652         }
 653
 654         if (!spec->pattern) {
 655                 *base = git__next_line(pattern);
 656                 return -1;
 657         } else {
 658                 /* strip '\' that might have be used for internal whitespace */
 659                 spec->length = git__unescape(spec->pattern);
 660                 /* TODO: convert remaining '\' into '/' for POSIX ??? */
 661         }
 662
 663         return 0;
 664 }
 665
 666 static bool parse_optimized_patterns(
 667         git_attr_fnmatch *spec,
 668         git_pool *pool,
 669         const char *pattern)
 670 {
 671         if (!pattern[1] && (pattern[0] == '*' || pattern[0] == '.')) {
 672                 spec->flags = GIT_ATTR_FNMATCH_MATCH_ALL;
 673                 spec->pattern = git_pool_strndup(pool, pattern, 1);
 674                 spec->length = 1;
 675
 676                 return true;
 677         }
 678
 679         return false;
 680 }
 681
 682 static int sort_by_hash_and_name(const void *a_raw, const void *b_raw)
 683 {
 684         const git_attr_name *a = a_raw;
 685         const git_attr_name *b = b_raw;
 686
 687         if (b->name_hash < a->name_hash)
 688                 return 1;
 689         else if (b->name_hash > a->name_hash)
 690                 return -1;
 691         else
 692                 return strcmp(b->name, a->name);
 693 }
 694
 695 static void git_attr_assignment__free(git_attr_assignment *assign)
 696 {
 697         /* name and value are stored in a git_pool associated with the
 698          * git_attr_file, so they do not need to be freed here
 699          */
 700         assign->name = NULL;
 701         assign->value = NULL;
 702         git__free(assign);
 703 }
 704
 705 static int merge_assignments(void **old_raw, void *new_raw)
 706 {
 707         git_attr_assignment **old = (git_attr_assignment **)old_raw;
 708         git_attr_assignment *new = (git_attr_assignment *)new_raw;
 709
 710         GIT_REFCOUNT_DEC(*old, git_attr_assignment__free);
 711         *old = new;
 712         return GIT_EEXISTS;
 713 }
 714
 715 int git_attr_assignment__parse(
 716         git_repository *repo,
 717         git_pool *pool,
 718         git_vector *assigns,
 719         const char **base)
 720 {
 721         int error;
 722         const char *scan = *base;
 723         git_attr_assignment *assign = NULL;
 724
 725         assert(assigns && !assigns->length);
 726
 727         git_vector_set_cmp(assigns, sort_by_hash_and_name);
 728
 729         while (*scan && *scan != '\n') {
 730                 const char *name_start, *value_start;
 731
 732                 /* skip leading blanks */
 733                 while (git__isspace(*scan) && *scan != '\n') scan++;
 734
 735                 /* allocate assign if needed */
 736                 if (!assign) {
 737                         assign = git__calloc(1, sizeof(git_attr_assignment));
 738                         GITERR_CHECK_ALLOC(assign);
 739                         GIT_REFCOUNT_INC(assign);
 740                 }
 741
 742                 assign->name_hash = 5381;
 743                 assign->value = git_attr__true;
 744
 745                 /* look for magic name prefixes */
 746                 if (*scan == '-') {
 747                         assign->value = git_attr__false;
 748                         scan++;
 749                 } else if (*scan == '!') {
 750                         assign->value = git_attr__unset; /* explicit unspecified state */
 751                         scan++;
 752                 } else if (*scan == '#') /* comment rest of line */
 753                         break;
 754
 755                 /* find the name */
 756                 name_start = scan;
 757                 while (*scan && !git__isspace(*scan) && *scan != '=') {
 758                         assign->name_hash =
 759                                 ((assign->name_hash << 5) + assign->name_hash) + *scan;
 760                         scan++;
 761                 }
 762                 if (scan == name_start) {
 763                         /* must have found lone prefix (" - ") or leading = ("=foo")
 764                          * or end of buffer -- advance until whitespace and continue
 765                          */
 766                         while (*scan && !git__isspace(*scan)) scan++;
 767                         continue;
 768                 }
 769
 770                 /* allocate permanent storage for name */
 771                 assign->name = git_pool_strndup(pool, name_start, scan - name_start);
 772                 GITERR_CHECK_ALLOC(assign->name);
 773
 774                 /* if there is an equals sign, find the value */
 775                 if (*scan == '=') {
 776                         for (value_start = ++scan; *scan && !git__isspace(*scan); ++scan);
 777
 778                         /* if we found a value, allocate permanent storage for it */
 779                         if (scan > value_start) {
 780                                 assign->value = git_pool_strndup(pool, value_start, scan - value_start);
 781                                 GITERR_CHECK_ALLOC(assign->value);
 782                         }
 783                 }
 784
 785                 /* expand macros (if given a repo with a macro cache) */
 786                 if (repo != NULL && assign->value == git_attr__true) {
 787                         git_attr_rule *macro =
 788                                 git_attr_cache__lookup_macro(repo, assign->name);
 789
 790                         if (macro != NULL) {
 791                                 unsigned int i;
 792                                 git_attr_assignment *massign;
 793
 794                                 git_vector_foreach(&macro->assigns, i, massign) {
 795                                         GIT_REFCOUNT_INC(massign);
 796
 797                                         error = git_vector_insert_sorted(
 798                                                 assigns, massign, &merge_assignments);
 799                                         if (error < 0 && error != GIT_EEXISTS) {
 800                                                 git_attr_assignment__free(assign);
 801                                                 return error;
 802                                         }
 803                                 }
 804                         }
 805                 }
 806
 807                 /* insert allocated assign into vector */
 808                 error = git_vector_insert_sorted(assigns, assign, &merge_assignments);
 809                 if (error < 0 && error != GIT_EEXISTS)
 810                         return error;
 811
 812                 /* clear assign since it is now "owned" by the vector */
 813                 assign = NULL;
 814         }
 815
 816         if (assign != NULL)
 817                 git_attr_assignment__free(assign);
 818
 819         *base = git__next_line(scan);
 820
 821         return (assigns->length == 0) ? GIT_ENOTFOUND : 0;
 822 }
 823
 824 static void git_attr_rule__clear(git_attr_rule *rule)
 825 {
 826         unsigned int i;
 827         git_attr_assignment *assign;
 828
 829         if (!rule)
 830                 return;
 831
 832         if (!(rule->match.flags & GIT_ATTR_FNMATCH_IGNORE)) {
 833                 git_vector_foreach(&rule->assigns, i, assign)
 834                         GIT_REFCOUNT_DEC(assign, git_attr_assignment__free);
 835                 git_vector_free(&rule->assigns);
 836         }
 837
 838         /* match.pattern is stored in a git_pool, so no need to free */
 839         rule->match.pattern = NULL;
 840         rule->match.length = 0;
 841 }
 842
 843 void git_attr_rule__free(git_attr_rule *rule)
 844 {
 845         git_attr_rule__clear(rule);
 846         git__free(rule);
 847 }
 848
 849 int git_attr_session__init(git_attr_session *session, git_repository *repo)
 850 {
 851         assert(repo);
 852
 853         session->key = git_atomic_inc(&repo->attr_session_key);
 854
 855         return 0;
 856 }
 857
 858 void git_attr_session__free(git_attr_session *session)
 859 {
 860         if (!session)
 861                 return;
 862
 863         git_buf_free(&session->sysdir);
 864         git_buf_free(&session->tmp);
 865
 866         memset(session, 0, sizeof(git_attr_session));
 867 }