attr.c

   1 /*
   2  * Handle git attributes.  See gitattributes(5) for a description of
   3  * the file syntax, and Documentation/technical/api-gitattributes.txt
   4  * for a description of the API.
   5  *
   6  * One basic design decision here is that we are not going to support
   7  * an insanely large number of attributes.
   8  */
   9
  10 #define NO_THE_INDEX_COMPATIBILITY_MACROS
  11 #include "cache.h"
  12 #include "exec_cmd.h"
  13 #include "attr.h"
  14 #include "dir.h"
  15
  16 const char git_attr__true[] = "(builtin)true";
  17 const char git_attr__false[] = "\0(builtin)false";
  18 static const char git_attr__unknown[] = "(builtin)unknown";
  19 #define ATTR__TRUE git_attr__true
  20 #define ATTR__FALSE git_attr__false
  21 #define ATTR__UNSET NULL
  22 #define ATTR__UNKNOWN git_attr__unknown
  23
  24 /* This is a randomly chosen prime. */
  25 #define HASHSIZE 257
  26
  27 #ifndef DEBUG_ATTR
  28 #define DEBUG_ATTR 0
  29 #endif
  30
  31 struct git_attr {
  32         struct git_attr *next;
  33         unsigned h;
  34         int attr_nr;
  35         int maybe_macro;
  36         int maybe_real;
  37         char name[FLEX_ARRAY];
  38 };
  39 static int attr_nr;
  40 static int cannot_trust_maybe_real;
  41
  42 static struct git_attr_check *check_all_attr;
  43 static struct git_attr *(git_attr_hash[HASHSIZE]);
  44
  45 char *git_attr_name(struct git_attr *attr)
  46 {
  47         return attr->name;
  48 }
  49
  50 static unsigned hash_name(const char *name, int namelen)
  51 {
  52         unsigned val = 0, c;
  53
  54         while (namelen--) {
  55                 c = *name++;
  56                 val = ((val << 7) | (val >> 22)) ^ c;
  57         }
  58         return val;
  59 }
  60
  61 static int invalid_attr_name(const char *name, int namelen)
  62 {
  63         /*
  64          * Attribute name cannot begin with '-' and must consist of
  65          * characters from [-A-Za-z0-9_.].
  66          */
  67         if (namelen <= 0 || *name == '-')
  68                 return -1;
  69         while (namelen--) {
  70                 char ch = *name++;
  71                 if (! (ch == '-' || ch == '.' || ch == '_' ||
  72                        ('0' <= ch && ch <= '9') ||
  73                        ('a' <= ch && ch <= 'z') ||
  74                        ('A' <= ch && ch <= 'Z')) )
  75                         return -1;
  76         }
  77         return 0;
  78 }
  79
  80 static struct git_attr *git_attr_internal(const char *name, int len)
  81 {
  82         unsigned hval = hash_name(name, len);
  83         unsigned pos = hval % HASHSIZE;
  84         struct git_attr *a;
  85
  86         for (a = git_attr_hash[pos]; a; a = a->next) {
  87                 if (a->h == hval &&
  88                     !memcmp(a->name, name, len) && !a->name[len])
  89                         return a;
  90         }
  91
  92         if (invalid_attr_name(name, len))
  93                 return NULL;
  94
  95         a = xmalloc(sizeof(*a) + len + 1);
  96         memcpy(a->name, name, len);
  97         a->name[len] = 0;
  98         a->h = hval;
  99         a->next = git_attr_hash[pos];
 100         a->attr_nr = attr_nr++;
 101         a->maybe_macro = 0;
 102         a->maybe_real = 0;
 103         git_attr_hash[pos] = a;
 104
 105         REALLOC_ARRAY(check_all_attr, attr_nr);
 106         check_all_attr[a->attr_nr].attr = a;
 107         check_all_attr[a->attr_nr].value = ATTR__UNKNOWN;
 108         return a;
 109 }
 110
 111 struct git_attr *git_attr(const char *name)
 112 {
 113         return git_attr_internal(name, strlen(name));
 114 }
 115
 116 /* What does a matched pattern decide? */
 117 struct attr_state {
 118         struct git_attr *attr;
 119         const char *setto;
 120 };
 121
 122 struct pattern {
 123         const char *pattern;
 124         int patternlen;
 125         int nowildcardlen;
 126         int flags;              /* EXC_FLAG_* */
 127 };
 128
 129 /*
 130  * One rule, as from a .gitattributes file.
 131  *
 132  * If is_macro is true, then u.attr is a pointer to the git_attr being
 133  * defined.
 134  *
 135  * If is_macro is false, then u.pattern points at the filename pattern
 136  * to which the rule applies.  (The memory pointed to is part of the
 137  * memory block allocated for the match_attr instance.)
 138  *
 139  * In either case, num_attr is the number of attributes affected by
 140  * this rule, and state is an array listing them.  The attributes are
 141  * listed as they appear in the file (macros unexpanded).
 142  */
 143 struct match_attr {
 144         union {
 145                 struct pattern pat;
 146                 struct git_attr *attr;
 147         } u;
 148         char is_macro;
 149         unsigned num_attr;
 150         struct attr_state state[FLEX_ARRAY];
 151 };
 152
 153 static const char blank[] = " \t\r\n";
 154
 155 /*
 156  * Parse a whitespace-delimited attribute state (i.e., "attr",
 157  * "-attr", "!attr", or "attr=value") from the string starting at src.
 158  * If e is not NULL, write the results to *e.  Return a pointer to the
 159  * remainder of the string (with leading whitespace removed), or NULL
 160  * if there was an error.
 161  */
 162 static const char *parse_attr(const char *src, int lineno, const char *cp,
 163                               struct attr_state *e)
 164 {
 165         const char *ep, *equals;
 166         int len;
 167
 168         ep = cp + strcspn(cp, blank);
 169         equals = strchr(cp, '=');
 170         if (equals && ep < equals)
 171                 equals = NULL;
 172         if (equals)
 173                 len = equals - cp;
 174         else
 175                 len = ep - cp;
 176         if (!e) {
 177                 if (*cp == '-' || *cp == '!') {
 178                         cp++;
 179                         len--;
 180                 }
 181                 if (invalid_attr_name(cp, len)) {
 182                         fprintf(stderr,
 183                                 "%.*s is not a valid attribute name: %s:%d\n",
 184                                 len, cp, src, lineno);
 185                         return NULL;
 186                 }
 187         } else {
 188                 if (*cp == '-' || *cp == '!') {
 189                         e->setto = (*cp == '-') ? ATTR__FALSE : ATTR__UNSET;
 190                         cp++;
 191                         len--;
 192                 }
 193                 else if (!equals)
 194                         e->setto = ATTR__TRUE;
 195                 else {
 196                         e->setto = xmemdupz(equals + 1, ep - equals - 1);
 197                 }
 198                 e->attr = git_attr_internal(cp, len);
 199         }
 200         return ep + strspn(ep, blank);
 201 }
 202
 203 static struct match_attr *parse_attr_line(const char *line, const char *src,
 204                                           int lineno, int macro_ok)
 205 {
 206         int namelen;
 207         int num_attr, i;
 208         const char *cp, *name, *states;
 209         struct match_attr *res = NULL;
 210         int is_macro;
 211
 212         cp = line + strspn(line, blank);
 213         if (!*cp || *cp == '#')
 214                 return NULL;
 215         name = cp;
 216         namelen = strcspn(name, blank);
 217         if (strlen(ATTRIBUTE_MACRO_PREFIX) < namelen &&
 218             starts_with(name, ATTRIBUTE_MACRO_PREFIX)) {
 219                 if (!macro_ok) {
 220                         fprintf(stderr, "%s not allowed: %s:%d\n",
 221                                 name, src, lineno);
 222                         return NULL;
 223                 }
 224                 is_macro = 1;
 225                 name += strlen(ATTRIBUTE_MACRO_PREFIX);
 226                 name += strspn(name, blank);
 227                 namelen = strcspn(name, blank);
 228                 if (invalid_attr_name(name, namelen)) {
 229                         fprintf(stderr,
 230                                 "%.*s is not a valid attribute name: %s:%d\n",
 231                                 namelen, name, src, lineno);
 232                         return NULL;
 233                 }
 234         }
 235         else
 236                 is_macro = 0;
 237
 238         states = name + namelen;
 239         states += strspn(states, blank);
 240
 241         /* First pass to count the attr_states */
 242         for (cp = states, num_attr = 0; *cp; num_attr++) {
 243                 cp = parse_attr(src, lineno, cp, NULL);
 244                 if (!cp)
 245                         return NULL;
 246         }
 247
 248         res = xcalloc(1,
 249                       sizeof(*res) +
 250                       sizeof(struct attr_state) * num_attr +
 251                       (is_macro ? 0 : namelen + 1));
 252         if (is_macro) {
 253                 res->u.attr = git_attr_internal(name, namelen);
 254                 res->u.attr->maybe_macro = 1;
 255         } else {
 256                 char *p = (char *)&(res->state[num_attr]);
 257                 memcpy(p, name, namelen);
 258                 res->u.pat.pattern = p;
 259                 parse_exclude_pattern(&res->u.pat.pattern,
 260                                       &res->u.pat.patternlen,
 261                                       &res->u.pat.flags,
 262                                       &res->u.pat.nowildcardlen);
 263                 if (res->u.pat.flags & EXC_FLAG_NEGATIVE) {
 264                         warning(_("Negative patterns are ignored in git attributes\n"
 265                                   "Use '\\!' for literal leading exclamation."));
 266                         return NULL;
 267                 }
 268         }
 269         res->is_macro = is_macro;
 270         res->num_attr = num_attr;
 271
 272         /* Second pass to fill the attr_states */
 273         for (cp = states, i = 0; *cp; i++) {
 274                 cp = parse_attr(src, lineno, cp, &(res->state[i]));
 275                 if (!is_macro)
 276                         res->state[i].attr->maybe_real = 1;
 277                 if (res->state[i].attr->maybe_macro)
 278                         cannot_trust_maybe_real = 1;
 279         }
 280
 281         return res;
 282 }
 283
 284 /*
 285  * Like info/exclude and .gitignore, the attribute information can
 286  * come from many places.
 287  *
 288  * (1) .gitattribute file of the same directory;
 289  * (2) .gitattribute file of the parent directory if (1) does not have
 290  *      any match; this goes recursively upwards, just like .gitignore.
 291  * (3) $GIT_DIR/info/attributes, which overrides both of the above.
 292  *
 293  * In the same file, later entries override the earlier match, so in the
 294  * global list, we would have entries from info/attributes the earliest
 295  * (reading the file from top to bottom), .gitattribute of the root
 296  * directory (again, reading the file from top to bottom) down to the
 297  * current directory, and then scan the list backwards to find the first match.
 298  * This is exactly the same as what is_excluded() does in dir.c to deal with
 299  * .gitignore
 300  */
 301
 302 static struct attr_stack {
 303         struct attr_stack *prev;
 304         char *origin;
 305         size_t originlen;
 306         unsigned num_matches;
 307         unsigned alloc;
 308         struct match_attr **attrs;
 309 } *attr_stack;
 310
 311 static void free_attr_elem(struct attr_stack *e)
 312 {
 313         int i;
 314         free(e->origin);
 315         for (i = 0; i < e->num_matches; i++) {
 316                 struct match_attr *a = e->attrs[i];
 317                 int j;
 318                 for (j = 0; j < a->num_attr; j++) {
 319                         const char *setto = a->state[j].setto;
 320                         if (setto == ATTR__TRUE ||
 321                             setto == ATTR__FALSE ||
 322                             setto == ATTR__UNSET ||
 323                             setto == ATTR__UNKNOWN)
 324                                 ;
 325                         else
 326                                 free((char *) setto);
 327                 }
 328                 free(a);
 329         }
 330         free(e->attrs);
 331         free(e);
 332 }
 333
 334 static const char *builtin_attr[] = {
 335         "[attr]binary -diff -merge -text",
 336         NULL,
 337 };
 338
 339 static void handle_attr_line(struct attr_stack *res,
 340                              const char *line,
 341                              const char *src,
 342                              int lineno,
 343                              int macro_ok)
 344 {
 345         struct match_attr *a;
 346
 347         a = parse_attr_line(line, src, lineno, macro_ok);
 348         if (!a)
 349                 return;
 350         ALLOC_GROW(res->attrs, res->num_matches + 1, res->alloc);
 351         res->attrs[res->num_matches++] = a;
 352 }
 353
 354 static struct attr_stack *read_attr_from_array(const char **list)
 355 {
 356         struct attr_stack *res;
 357         const char *line;
 358         int lineno = 0;
 359
 360         res = xcalloc(1, sizeof(*res));
 361         while ((line = *(list++)) != NULL)
 362                 handle_attr_line(res, line, "[builtin]", ++lineno, 1);
 363         return res;
 364 }
 365
 366 static enum git_attr_direction direction;
 367 static struct index_state *use_index;
 368
 369 static struct attr_stack *read_attr_from_file(const char *path, int macro_ok)
 370 {
 371         FILE *fp = fopen(path, "r");
 372         struct attr_stack *res;
 373         char buf[2048];
 374         int lineno = 0;
 375
 376         if (!fp) {
 377                 if (errno != ENOENT && errno != ENOTDIR)
 378                         warn_on_inaccessible(path);
 379                 return NULL;
 380         }
 381         res = xcalloc(1, sizeof(*res));
 382         while (fgets(buf, sizeof(buf), fp))
 383                 handle_attr_line(res, buf, path, ++lineno, macro_ok);
 384         fclose(fp);
 385         return res;
 386 }
 387
 388 static struct attr_stack *read_attr_from_index(const char *path, int macro_ok)
 389 {
 390         struct attr_stack *res;
 391         char *buf, *sp;
 392         int lineno = 0;
 393
 394         buf = read_blob_data_from_index(use_index ? use_index : &the_index, path, NULL);
 395         if (!buf)
 396                 return NULL;
 397
 398         res = xcalloc(1, sizeof(*res));
 399         for (sp = buf; *sp; ) {
 400                 char *ep;
 401                 int more;
 402                 for (ep = sp; *ep && *ep != '\n'; ep++)
 403                         ;
 404                 more = (*ep == '\n');
 405                 *ep = '\0';
 406                 handle_attr_line(res, sp, path, ++lineno, macro_ok);
 407                 sp = ep + more;
 408         }
 409         free(buf);
 410         return res;
 411 }
 412
 413 static struct attr_stack *read_attr(const char *path, int macro_ok)
 414 {
 415         struct attr_stack *res;
 416
 417         if (direction == GIT_ATTR_CHECKOUT) {
 418                 res = read_attr_from_index(path, macro_ok);
 419                 if (!res)
 420                         res = read_attr_from_file(path, macro_ok);
 421         }
 422         else if (direction == GIT_ATTR_CHECKIN) {
 423                 res = read_attr_from_file(path, macro_ok);
 424                 if (!res)
 425                         /*
 426                          * There is no checked out .gitattributes file there, but
 427                          * we might have it in the index.  We allow operation in a
 428                          * sparsely checked out work tree, so read from it.
 429                          */
 430                         res = read_attr_from_index(path, macro_ok);
 431         }
 432         else
 433                 res = read_attr_from_index(path, macro_ok);
 434         if (!res)
 435                 res = xcalloc(1, sizeof(*res));
 436         return res;
 437 }
 438
 439 #if DEBUG_ATTR
 440 static void debug_info(const char *what, struct attr_stack *elem)
 441 {
 442         fprintf(stderr, "%s: %s\n", what, elem->origin ? elem->origin : "()");
 443 }
 444 static void debug_set(const char *what, const char *match, struct git_attr *attr, const void *v)
 445 {
 446         const char *value = v;
 447
 448         if (ATTR_TRUE(value))
 449                 value = "set";
 450         else if (ATTR_FALSE(value))
 451                 value = "unset";
 452         else if (ATTR_UNSET(value))
 453                 value = "unspecified";
 454
 455         fprintf(stderr, "%s: %s => %s (%s)\n",
 456                 what, attr->name, (char *) value, match);
 457 }
 458 #define debug_push(a) debug_info("push", (a))
 459 #define debug_pop(a) debug_info("pop", (a))
 460 #else
 461 #define debug_push(a) do { ; } while (0)
 462 #define debug_pop(a) do { ; } while (0)
 463 #define debug_set(a,b,c,d) do { ; } while (0)
 464 #endif
 465
 466 static void drop_attr_stack(void)
 467 {
 468         while (attr_stack) {
 469                 struct attr_stack *elem = attr_stack;
 470                 attr_stack = elem->prev;
 471                 free_attr_elem(elem);
 472         }
 473 }
 474
 475 static const char *git_etc_gitattributes(void)
 476 {
 477         static const char *system_wide;
 478         if (!system_wide)
 479                 system_wide = system_path(ETC_GITATTRIBUTES);
 480         return system_wide;
 481 }
 482
 483 static int git_attr_system(void)
 484 {
 485         return !git_env_bool("GIT_ATTR_NOSYSTEM", 0);
 486 }
 487
 488 static void bootstrap_attr_stack(void)
 489 {
 490         struct attr_stack *elem;
 491         char *xdg_attributes_file;
 492
 493         if (attr_stack)
 494                 return;
 495
 496         elem = read_attr_from_array(builtin_attr);
 497         elem->origin = NULL;
 498         elem->prev = attr_stack;
 499         attr_stack = elem;
 500
 501         if (git_attr_system()) {
 502                 elem = read_attr_from_file(git_etc_gitattributes(), 1);
 503                 if (elem) {
 504                         elem->origin = NULL;
 505                         elem->prev = attr_stack;
 506                         attr_stack = elem;
 507                 }
 508         }
 509
 510         if (!git_attributes_file) {
 511                 home_config_paths(NULL, &xdg_attributes_file, "attributes");
 512                 git_attributes_file = xdg_attributes_file;
 513         }
 514         if (git_attributes_file) {
 515                 elem = read_attr_from_file(git_attributes_file, 1);
 516                 if (elem) {
 517                         elem->origin = NULL;
 518                         elem->prev = attr_stack;
 519                         attr_stack = elem;
 520                 }
 521         }
 522
 523         if (!is_bare_repository() || direction == GIT_ATTR_INDEX) {
 524                 elem = read_attr(GITATTRIBUTES_FILE, 1);
 525                 elem->origin = xstrdup("");
 526                 elem->originlen = 0;
 527                 elem->prev = attr_stack;
 528                 attr_stack = elem;
 529                 debug_push(elem);
 530         }
 531
 532         elem = read_attr_from_file(git_path(INFOATTRIBUTES_FILE), 1);
 533         if (!elem)
 534                 elem = xcalloc(1, sizeof(*elem));
 535         elem->origin = NULL;
 536         elem->prev = attr_stack;
 537         attr_stack = elem;
 538 }
 539
 540 static void prepare_attr_stack(const char *path, int dirlen)
 541 {
 542         struct attr_stack *elem, *info;
 543         int len;
 544         const char *cp;
 545
 546         /*
 547          * At the bottom of the attribute stack is the built-in
 548          * set of attribute definitions, followed by the contents
 549          * of $(prefix)/etc/gitattributes and a file specified by
 550          * core.attributesfile.  Then, contents from
 551          * .gitattribute files from directories closer to the
 552          * root to the ones in deeper directories are pushed
 553          * to the stack.  Finally, at the very top of the stack
 554          * we always keep the contents of $GIT_DIR/info/attributes.
 555          *
 556          * When checking, we use entries from near the top of the
 557          * stack, preferring $GIT_DIR/info/attributes, then
 558          * .gitattributes in deeper directories to shallower ones,
 559          * and finally use the built-in set as the default.
 560          */
 561         bootstrap_attr_stack();
 562
 563         /*
 564          * Pop the "info" one that is always at the top of the stack.
 565          */
 566         info = attr_stack;
 567         attr_stack = info->prev;
 568
 569         /*
 570          * Pop the ones from directories that are not the prefix of
 571          * the path we are checking. Break out of the loop when we see
 572          * the root one (whose origin is an empty string "") or the builtin
 573          * one (whose origin is NULL) without popping it.
 574          */
 575         while (attr_stack->origin) {
 576                 int namelen = strlen(attr_stack->origin);
 577
 578                 elem = attr_stack;
 579                 if (namelen <= dirlen &&
 580                     !strncmp(elem->origin, path, namelen) &&
 581                     (!namelen || path[namelen] == '/'))
 582                         break;
 583
 584                 debug_pop(elem);
 585                 attr_stack = elem->prev;
 586                 free_attr_elem(elem);
 587         }
 588
 589         /*
 590          * Read from parent directories and push them down
 591          */
 592         if (!is_bare_repository() || direction == GIT_ATTR_INDEX) {
 593                 /*
 594                  * bootstrap_attr_stack() should have added, and the
 595                  * above loop should have stopped before popping, the
 596                  * root element whose attr_stack->origin is set to an
 597                  * empty string.
 598                  */
 599                 struct strbuf pathbuf = STRBUF_INIT;
 600
 601                 assert(attr_stack->origin);
 602                 while (1) {
 603                         len = strlen(attr_stack->origin);
 604                         if (dirlen <= len)
 605                                 break;
 606                         cp = memchr(path + len + 1, '/', dirlen - len - 1);
 607                         if (!cp)
 608                                 cp = path + dirlen;
 609                         strbuf_add(&pathbuf, path, cp - path);
 610                         strbuf_addch(&pathbuf, '/');
 611                         strbuf_addstr(&pathbuf, GITATTRIBUTES_FILE);
 612                         elem = read_attr(pathbuf.buf, 0);
 613                         strbuf_setlen(&pathbuf, cp - path);
 614                         elem->origin = strbuf_detach(&pathbuf, &elem->originlen);
 615                         elem->prev = attr_stack;
 616                         attr_stack = elem;
 617                         debug_push(elem);
 618                 }
 619
 620                 strbuf_release(&pathbuf);
 621         }
 622
 623         /*
 624          * Finally push the "info" one at the top of the stack.
 625          */
 626         info->prev = attr_stack;
 627         attr_stack = info;
 628 }
 629
 630 static int path_matches(const char *pathname, int pathlen,
 631                         int basename_offset,
 632                         const struct pattern *pat,
 633                         const char *base, int baselen)
 634 {
 635         const char *pattern = pat->pattern;
 636         int prefix = pat->nowildcardlen;
 637         int isdir = (pathlen && pathname[pathlen - 1] == '/');
 638
 639         if ((pat->flags & EXC_FLAG_MUSTBEDIR) && !isdir)
 640                 return 0;
 641
 642         if (pat->flags & EXC_FLAG_NODIR) {
 643                 return match_basename(pathname + basename_offset,
 644                                       pathlen - basename_offset - isdir,
 645                                       pattern, prefix,
 646                                       pat->patternlen, pat->flags);
 647         }
 648         return match_pathname(pathname, pathlen - isdir,
 649                               base, baselen,
 650                               pattern, prefix, pat->patternlen, pat->flags);
 651 }
 652
 653 static int macroexpand_one(int attr_nr, int rem);
 654
 655 static int fill_one(const char *what, struct match_attr *a, int rem)
 656 {
 657         struct git_attr_check *check = check_all_attr;
 658         int i;
 659
 660         for (i = a->num_attr - 1; 0 < rem && 0 <= i; i--) {
 661                 struct git_attr *attr = a->state[i].attr;
 662                 const char **n = &(check[attr->attr_nr].value);
 663                 const char *v = a->state[i].setto;
 664
 665                 if (*n == ATTR__UNKNOWN) {
 666                         debug_set(what,
 667                                   a->is_macro ? a->u.attr->name : a->u.pat.pattern,
 668                                   attr, v);
 669                         *n = v;
 670                         rem--;
 671                         rem = macroexpand_one(attr->attr_nr, rem);
 672                 }
 673         }
 674         return rem;
 675 }
 676
 677 static int fill(const char *path, int pathlen, int basename_offset,
 678                 struct attr_stack *stk, int rem)
 679 {
 680         int i;
 681         const char *base = stk->origin ? stk->origin : "";
 682
 683         for (i = stk->num_matches - 1; 0 < rem && 0 <= i; i--) {
 684                 struct match_attr *a = stk->attrs[i];
 685                 if (a->is_macro)
 686                         continue;
 687                 if (path_matches(path, pathlen, basename_offset,
 688                                  &a->u.pat, base, stk->originlen))
 689                         rem = fill_one("fill", a, rem);
 690         }
 691         return rem;
 692 }
 693
 694 static int macroexpand_one(int nr, int rem)
 695 {
 696         struct attr_stack *stk;
 697         struct match_attr *a = NULL;
 698         int i;
 699
 700         if (check_all_attr[nr].value != ATTR__TRUE ||
 701             !check_all_attr[nr].attr->maybe_macro)
 702                 return rem;
 703
 704         for (stk = attr_stack; !a && stk; stk = stk->prev)
 705                 for (i = stk->num_matches - 1; !a && 0 <= i; i--) {
 706                         struct match_attr *ma = stk->attrs[i];
 707                         if (!ma->is_macro)
 708                                 continue;
 709                         if (ma->u.attr->attr_nr == nr)
 710                                 a = ma;
 711                 }
 712
 713         if (a)
 714                 rem = fill_one("expand", a, rem);
 715
 716         return rem;
 717 }
 718
 719 /*
 720  * Collect attributes for path into the array pointed to by
 721  * check_all_attr. If num is non-zero, only attributes in check[] are
 722  * collected. Otherwise all attributes are collected.
 723  */
 724 static void collect_some_attrs(const char *path, int num,
 725                                struct git_attr_check *check)
 726
 727 {
 728         struct attr_stack *stk;
 729         int i, pathlen, rem, dirlen;
 730         const char *cp, *last_slash = NULL;
 731         int basename_offset;
 732
 733         for (cp = path; *cp; cp++) {
 734                 if (*cp == '/' && cp[1])
 735                         last_slash = cp;
 736         }
 737         pathlen = cp - path;
 738         if (last_slash) {
 739                 basename_offset = last_slash + 1 - path;
 740                 dirlen = last_slash - path;
 741         } else {
 742                 basename_offset = 0;
 743                 dirlen = 0;
 744         }
 745
 746         prepare_attr_stack(path, dirlen);
 747         for (i = 0; i < attr_nr; i++)
 748                 check_all_attr[i].value = ATTR__UNKNOWN;
 749         if (num && !cannot_trust_maybe_real) {
 750                 rem = 0;
 751                 for (i = 0; i < num; i++) {
 752                         if (!check[i].attr->maybe_real) {
 753                                 struct git_attr_check *c;
 754                                 c = check_all_attr + check[i].attr->attr_nr;
 755                                 c->value = ATTR__UNSET;
 756                                 rem++;
 757                         }
 758                 }
 759                 if (rem == num)
 760                         return;
 761         }
 762
 763         rem = attr_nr;
 764         for (stk = attr_stack; 0 < rem && stk; stk = stk->prev)
 765                 rem = fill(path, pathlen, basename_offset, stk, rem);
 766 }
 767
 768 int git_check_attr(const char *path, int num, struct git_attr_check *check)
 769 {
 770         int i;
 771
 772         collect_some_attrs(path, num, check);
 773
 774         for (i = 0; i < num; i++) {
 775                 const char *value = check_all_attr[check[i].attr->attr_nr].value;
 776                 if (value == ATTR__UNKNOWN)
 777                         value = ATTR__UNSET;
 778                 check[i].value = value;
 779         }
 780
 781         return 0;
 782 }
 783
 784 int git_all_attrs(const char *path, int *num, struct git_attr_check **check)
 785 {
 786         int i, count, j;
 787
 788         collect_some_attrs(path, 0, NULL);
 789
 790         /* Count the number of attributes that are set. */
 791         count = 0;
 792         for (i = 0; i < attr_nr; i++) {
 793                 const char *value = check_all_attr[i].value;
 794                 if (value != ATTR__UNSET && value != ATTR__UNKNOWN)
 795                         ++count;
 796         }
 797         *num = count;
 798         *check = xmalloc(sizeof(**check) * count);
 799         j = 0;
 800         for (i = 0; i < attr_nr; i++) {
 801                 const char *value = check_all_attr[i].value;
 802                 if (value != ATTR__UNSET && value != ATTR__UNKNOWN) {
 803                         (*check)[j].attr = check_all_attr[i].attr;
 804                         (*check)[j].value = value;
 805                         ++j;
 806                 }
 807         }
 808
 809         return 0;
 810 }
 811
 812 void git_attr_set_direction(enum git_attr_direction new, struct index_state *istate)
 813 {
 814         enum git_attr_direction old = direction;
 815
 816         if (is_bare_repository() && new != GIT_ATTR_INDEX)
 817                 die("BUG: non-INDEX attr direction in a bare repo");
 818
 819         direction = new;
 820         if (new != old)
 821                 drop_attr_stack();
 822         use_index = istate;
 823 }