dir.c

   1 /*
   2  * This handles recursive filename detection with exclude
   3  * files, index knowledge etc..
   4  *
   5  * Copyright (C) Linus Torvalds, 2005-2006
   6  *               Junio Hamano, 2005-2006
   7  */
   8 #include "cache.h"
   9 #include "dir.h"
  10 #include "refs.h"
  11
  12 struct path_simplify {
  13         int len;
  14         const char *path;
  15 };
  16
  17 static int read_directory_recursive(struct dir_struct *dir, const char *path, int len,
  18         int check_only, const struct path_simplify *simplify);
  19 static int get_dtype(struct dirent *de, const char *path, int len);
  20
  21 static int common_prefix(const char **pathspec)
  22 {
  23         const char *path, *slash, *next;
  24         int prefix;
  25
  26         if (!pathspec)
  27                 return 0;
  28
  29         path = *pathspec;
  30         slash = strrchr(path, '/');
  31         if (!slash)
  32                 return 0;
  33
  34         /*
  35          * The first 'prefix' characters of 'path' are common leading
  36          * path components among the pathspecs we have seen so far,
  37          * including the trailing slash.
  38          */
  39         prefix = slash - path + 1;
  40         while ((next = *++pathspec) != NULL) {
  41                 int len, last_matching_slash = -1;
  42                 for (len = 0; len < prefix && next[len] == path[len]; len++)
  43                         if (next[len] == '/')
  44                                 last_matching_slash = len;
  45                 if (len == prefix)
  46                         continue;
  47                 if (last_matching_slash < 0)
  48                         return 0;
  49                 prefix = last_matching_slash + 1;
  50         }
  51         return prefix;
  52 }
  53
  54 int fill_directory(struct dir_struct *dir, const char **pathspec)
  55 {
  56         const char *path;
  57         int len;
  58
  59         /*
  60          * Calculate common prefix for the pathspec, and
  61          * use that to optimize the directory walk
  62          */
  63         len = common_prefix(pathspec);
  64         path = "";
  65
  66         if (len)
  67                 path = xmemdupz(*pathspec, len);
  68
  69         /* Read the directory and prune it */
  70         read_directory(dir, path, len, pathspec);
  71         return len;
  72 }
  73
  74 /*
  75  * Does 'match' match the given name?
  76  * A match is found if
  77  *
  78  * (1) the 'match' string is leading directory of 'name', or
  79  * (2) the 'match' string is a wildcard and matches 'name', or
  80  * (3) the 'match' string is exactly the same as 'name'.
  81  *
  82  * and the return value tells which case it was.
  83  *
  84  * It returns 0 when there is no match.
  85  */
  86 static int match_one(const char *match, const char *name, int namelen)
  87 {
  88         int matchlen;
  89
  90         /* If the match was just the prefix, we matched */
  91         if (!*match)
  92                 return MATCHED_RECURSIVELY;
  93
  94         for (;;) {
  95                 unsigned char c1 = *match;
  96                 unsigned char c2 = *name;
  97                 if (c1 == '\0' || is_glob_special(c1))
  98                         break;
  99                 if (c1 != c2)
 100                         return 0;
 101                 match++;
 102                 name++;
 103                 namelen--;
 104         }
 105
 106
 107         /*
 108          * If we don't match the matchstring exactly,
 109          * we need to match by fnmatch
 110          */
 111         matchlen = strlen(match);
 112         if (strncmp(match, name, matchlen))
 113                 return !fnmatch(match, name, 0) ? MATCHED_FNMATCH : 0;
 114
 115         if (namelen == matchlen)
 116                 return MATCHED_EXACTLY;
 117         if (match[matchlen-1] == '/' || name[matchlen] == '/')
 118                 return MATCHED_RECURSIVELY;
 119         return 0;
 120 }
 121
 122 /*
 123  * Given a name and a list of pathspecs, see if the name matches
 124  * any of the pathspecs.  The caller is also interested in seeing
 125  * all pathspec matches some names it calls this function with
 126  * (otherwise the user could have mistyped the unmatched pathspec),
 127  * and a mark is left in seen[] array for pathspec element that
 128  * actually matched anything.
 129  */
 130 int match_pathspec(const char **pathspec, const char *name, int namelen,
 131                 int prefix, char *seen)
 132 {
 133         int i, retval = 0;
 134
 135         if (!pathspec)
 136                 return 1;
 137
 138         name += prefix;
 139         namelen -= prefix;
 140
 141         for (i = 0; pathspec[i] != NULL; i++) {
 142                 int how;
 143                 const char *match = pathspec[i] + prefix;
 144                 if (seen && seen[i] == MATCHED_EXACTLY)
 145                         continue;
 146                 how = match_one(match, name, namelen);
 147                 if (how) {
 148                         if (retval < how)
 149                                 retval = how;
 150                         if (seen && seen[i] < how)
 151                                 seen[i] = how;
 152                 }
 153         }
 154         return retval;
 155 }
 156
 157 static int no_wildcard(const char *string)
 158 {
 159         return string[strcspn(string, "*?[{\\")] == '\0';
 160 }
 161
 162 void add_exclude(const char *string, const char *base,
 163                  int baselen, struct exclude_list *which)
 164 {
 165         struct exclude *x;
 166         size_t len;
 167         int to_exclude = 1;
 168         int flags = 0;
 169
 170         if (*string == '!') {
 171                 to_exclude = 0;
 172                 string++;
 173         }
 174         len = strlen(string);
 175         if (len && string[len - 1] == '/') {
 176                 char *s;
 177                 x = xmalloc(sizeof(*x) + len);
 178                 s = (char *)(x+1);
 179                 memcpy(s, string, len - 1);
 180                 s[len - 1] = '\0';
 181                 string = s;
 182                 x->pattern = s;
 183                 flags = EXC_FLAG_MUSTBEDIR;
 184         } else {
 185                 x = xmalloc(sizeof(*x));
 186                 x->pattern = string;
 187         }
 188         x->to_exclude = to_exclude;
 189         x->patternlen = strlen(string);
 190         x->base = base;
 191         x->baselen = baselen;
 192         x->flags = flags;
 193         if (!strchr(string, '/'))
 194                 x->flags |= EXC_FLAG_NODIR;
 195         if (no_wildcard(string))
 196                 x->flags |= EXC_FLAG_NOWILDCARD;
 197         if (*string == '*' && no_wildcard(string+1))
 198                 x->flags |= EXC_FLAG_ENDSWITH;
 199         ALLOC_GROW(which->excludes, which->nr + 1, which->alloc);
 200         which->excludes[which->nr++] = x;
 201 }
 202
 203 static void *read_skip_worktree_file_from_index(const char *path, size_t *size)
 204 {
 205         int pos, len;
 206         unsigned long sz;
 207         enum object_type type;
 208         void *data;
 209         struct index_state *istate = &the_index;
 210
 211         len = strlen(path);
 212         pos = index_name_pos(istate, path, len);
 213         if (pos < 0)
 214                 return NULL;
 215         if (!ce_skip_worktree(istate->cache[pos]))
 216                 return NULL;
 217         data = read_sha1_file(istate->cache[pos]->sha1, &type, &sz);
 218         if (!data || type != OBJ_BLOB) {
 219                 free(data);
 220                 return NULL;
 221         }
 222         *size = xsize_t(sz);
 223         return data;
 224 }
 225
 226 int add_excludes_from_file_to_list(const char *fname,
 227                                    const char *base,
 228                                    int baselen,
 229                                    char **buf_p,
 230                                    struct exclude_list *which,
 231                                    int check_index)
 232 {
 233         struct stat st;
 234         int fd, i;
 235         size_t size;
 236         char *buf, *entry;
 237
 238         fd = open(fname, O_RDONLY);
 239         if (fd < 0 || fstat(fd, &st) < 0) {
 240                 if (0 <= fd)
 241                         close(fd);
 242                 if (!check_index ||
 243                     (buf = read_skip_worktree_file_from_index(fname, &size)) == NULL)
 244                         return -1;
 245                 if (size == 0) {
 246                         free(buf);
 247                         return 0;
 248                 }
 249                 if (buf[size-1] != '\n') {
 250                         buf = xrealloc(buf, size+1);
 251                         buf[size++] = '\n';
 252                 }
 253         }
 254         else {
 255                 size = xsize_t(st.st_size);
 256                 if (size == 0) {
 257                         close(fd);
 258                         return 0;
 259                 }
 260                 buf = xmalloc(size+1);
 261                 if (read_in_full(fd, buf, size) != size) {
 262                         free(buf);
 263                         close(fd);
 264                         return -1;
 265                 }
 266                 buf[size++] = '\n';
 267                 close(fd);
 268         }
 269
 270         if (buf_p)
 271                 *buf_p = buf;
 272         entry = buf;
 273         for (i = 0; i < size; i++) {
 274                 if (buf[i] == '\n') {
 275                         if (entry != buf + i && entry[0] != '#') {
 276                                 buf[i - (i && buf[i-1] == '\r')] = 0;
 277                                 add_exclude(entry, base, baselen, which);
 278                         }
 279                         entry = buf + i + 1;
 280                 }
 281         }
 282         return 0;
 283 }
 284
 285 void add_excludes_from_file(struct dir_struct *dir, const char *fname)
 286 {
 287         if (add_excludes_from_file_to_list(fname, "", 0, NULL,
 288                                            &dir->exclude_list[EXC_FILE], 0) < 0)
 289                 die("cannot use %s as an exclude file", fname);
 290 }
 291
 292 static void prep_exclude(struct dir_struct *dir, const char *base, int baselen)
 293 {
 294         struct exclude_list *el;
 295         struct exclude_stack *stk = NULL;
 296         int current;
 297
 298         if ((!dir->exclude_per_dir) ||
 299             (baselen + strlen(dir->exclude_per_dir) >= PATH_MAX))
 300                 return; /* too long a path -- ignore */
 301
 302         /* Pop the ones that are not the prefix of the path being checked. */
 303         el = &dir->exclude_list[EXC_DIRS];
 304         while ((stk = dir->exclude_stack) != NULL) {
 305                 if (stk->baselen <= baselen &&
 306                     !strncmp(dir->basebuf, base, stk->baselen))
 307                         break;
 308                 dir->exclude_stack = stk->prev;
 309                 while (stk->exclude_ix < el->nr)
 310                         free(el->excludes[--el->nr]);
 311                 free(stk->filebuf);
 312                 free(stk);
 313         }
 314
 315         /* Read from the parent directories and push them down. */
 316         current = stk ? stk->baselen : -1;
 317         while (current < baselen) {
 318                 struct exclude_stack *stk = xcalloc(1, sizeof(*stk));
 319                 const char *cp;
 320
 321                 if (current < 0) {
 322                         cp = base;
 323                         current = 0;
 324                 }
 325                 else {
 326                         cp = strchr(base + current + 1, '/');
 327                         if (!cp)
 328                                 die("oops in prep_exclude");
 329                         cp++;
 330                 }
 331                 stk->prev = dir->exclude_stack;
 332                 stk->baselen = cp - base;
 333                 stk->exclude_ix = el->nr;
 334                 memcpy(dir->basebuf + current, base + current,
 335                        stk->baselen - current);
 336                 strcpy(dir->basebuf + stk->baselen, dir->exclude_per_dir);
 337                 add_excludes_from_file_to_list(dir->basebuf,
 338                                                dir->basebuf, stk->baselen,
 339                                                &stk->filebuf, el, 1);
 340                 dir->exclude_stack = stk;
 341                 current = stk->baselen;
 342         }
 343         dir->basebuf[baselen] = '\0';
 344 }
 345
 346 /* Scan the list and let the last match determine the fate.
 347  * Return 1 for exclude, 0 for include and -1 for undecided.
 348  */
 349 int excluded_from_list(const char *pathname,
 350                        int pathlen, const char *basename, int *dtype,
 351                        struct exclude_list *el)
 352 {
 353         int i;
 354
 355         if (el->nr) {
 356                 for (i = el->nr - 1; 0 <= i; i--) {
 357                         struct exclude *x = el->excludes[i];
 358                         const char *exclude = x->pattern;
 359                         int to_exclude = x->to_exclude;
 360
 361                         if (x->flags & EXC_FLAG_MUSTBEDIR) {
 362                                 if (!dtype) {
 363                                         if (!prefixcmp(pathname, exclude))
 364                                                 return to_exclude;
 365                                         else
 366                                                 continue;
 367                                 }
 368                                 if (*dtype == DT_UNKNOWN)
 369                                         *dtype = get_dtype(NULL, pathname, pathlen);
 370                                 if (*dtype != DT_DIR)
 371                                         continue;
 372                         }
 373
 374                         if (x->flags & EXC_FLAG_NODIR) {
 375                                 /* match basename */
 376                                 if (x->flags & EXC_FLAG_NOWILDCARD) {
 377                                         if (!strcmp(exclude, basename))
 378                                                 return to_exclude;
 379                                 } else if (x->flags & EXC_FLAG_ENDSWITH) {
 380                                         if (x->patternlen - 1 <= pathlen &&
 381                                             !strcmp(exclude + 1, pathname + pathlen - x->patternlen + 1))
 382                                                 return to_exclude;
 383                                 } else {
 384                                         if (fnmatch(exclude, basename, 0) == 0)
 385                                                 return to_exclude;
 386                                 }
 387                         }
 388                         else {
 389                                 /* match with FNM_PATHNAME:
 390                                  * exclude has base (baselen long) implicitly
 391                                  * in front of it.
 392                                  */
 393                                 int baselen = x->baselen;
 394                                 if (*exclude == '/')
 395                                         exclude++;
 396
 397                                 if (pathlen < baselen ||
 398                                     (baselen && pathname[baselen-1] != '/') ||
 399                                     strncmp(pathname, x->base, baselen))
 400                                     continue;
 401
 402                                 if (x->flags & EXC_FLAG_NOWILDCARD) {
 403                                         if (!strcmp(exclude, pathname + baselen))
 404                                                 return to_exclude;
 405                                 } else {
 406                                         if (fnmatch(exclude, pathname+baselen,
 407                                                     FNM_PATHNAME) == 0)
 408                                             return to_exclude;
 409                                 }
 410                         }
 411                 }
 412         }
 413         return -1; /* undecided */
 414 }
 415
 416 int excluded(struct dir_struct *dir, const char *pathname, int *dtype_p)
 417 {
 418         int pathlen = strlen(pathname);
 419         int st;
 420         const char *basename = strrchr(pathname, '/');
 421         basename = (basename) ? basename+1 : pathname;
 422
 423         prep_exclude(dir, pathname, basename-pathname);
 424         for (st = EXC_CMDL; st <= EXC_FILE; st++) {
 425                 switch (excluded_from_list(pathname, pathlen, basename,
 426                                            dtype_p, &dir->exclude_list[st])) {
 427                 case 0:
 428                         return 0;
 429                 case 1:
 430                         return 1;
 431                 }
 432         }
 433         return 0;
 434 }
 435
 436 static struct dir_entry *dir_entry_new(const char *pathname, int len)
 437 {
 438         struct dir_entry *ent;
 439
 440         ent = xmalloc(sizeof(*ent) + len + 1);
 441         ent->len = len;
 442         memcpy(ent->name, pathname, len);
 443         ent->name[len] = 0;
 444         return ent;
 445 }
 446
 447 static struct dir_entry *dir_add_name(struct dir_struct *dir, const char *pathname, int len)
 448 {
 449         if (cache_name_exists(pathname, len, ignore_case))
 450                 return NULL;
 451
 452         ALLOC_GROW(dir->entries, dir->nr+1, dir->alloc);
 453         return dir->entries[dir->nr++] = dir_entry_new(pathname, len);
 454 }
 455
 456 struct dir_entry *dir_add_ignored(struct dir_struct *dir, const char *pathname, int len)
 457 {
 458         if (!cache_name_is_other(pathname, len))
 459                 return NULL;
 460
 461         ALLOC_GROW(dir->ignored, dir->ignored_nr+1, dir->ignored_alloc);
 462         return dir->ignored[dir->ignored_nr++] = dir_entry_new(pathname, len);
 463 }
 464
 465 enum exist_status {
 466         index_nonexistent = 0,
 467         index_directory,
 468         index_gitdir
 469 };
 470
 471 /*
 472  * The index sorts alphabetically by entry name, which
 473  * means that a gitlink sorts as '\0' at the end, while
 474  * a directory (which is defined not as an entry, but as
 475  * the files it contains) will sort with the '/' at the
 476  * end.
 477  */
 478 static enum exist_status directory_exists_in_index(const char *dirname, int len)
 479 {
 480         int pos = cache_name_pos(dirname, len);
 481         if (pos < 0)
 482                 pos = -pos-1;
 483         while (pos < active_nr) {
 484                 struct cache_entry *ce = active_cache[pos++];
 485                 unsigned char endchar;
 486
 487                 if (strncmp(ce->name, dirname, len))
 488                         break;
 489                 endchar = ce->name[len];
 490                 if (endchar > '/')
 491                         break;
 492                 if (endchar == '/')
 493                         return index_directory;
 494                 if (!endchar && S_ISGITLINK(ce->ce_mode))
 495                         return index_gitdir;
 496         }
 497         return index_nonexistent;
 498 }
 499
 500 /*
 501  * When we find a directory when traversing the filesystem, we
 502  * have three distinct cases:
 503  *
 504  *  - ignore it
 505  *  - see it as a directory
 506  *  - recurse into it
 507  *
 508  * and which one we choose depends on a combination of existing
 509  * git index contents and the flags passed into the directory
 510  * traversal routine.
 511  *
 512  * Case 1: If we *already* have entries in the index under that
 513  * directory name, we always recurse into the directory to see
 514  * all the files.
 515  *
 516  * Case 2: If we *already* have that directory name as a gitlink,
 517  * we always continue to see it as a gitlink, regardless of whether
 518  * there is an actual git directory there or not (it might not
 519  * be checked out as a subproject!)
 520  *
 521  * Case 3: if we didn't have it in the index previously, we
 522  * have a few sub-cases:
 523  *
 524  *  (a) if "show_other_directories" is true, we show it as
 525  *      just a directory, unless "hide_empty_directories" is
 526  *      also true and the directory is empty, in which case
 527  *      we just ignore it entirely.
 528  *  (b) if it looks like a git directory, and we don't have
 529  *      'no_gitlinks' set we treat it as a gitlink, and show it
 530  *      as a directory.
 531  *  (c) otherwise, we recurse into it.
 532  */
 533 enum directory_treatment {
 534         show_directory,
 535         ignore_directory,
 536         recurse_into_directory
 537 };
 538
 539 static enum directory_treatment treat_directory(struct dir_struct *dir,
 540         const char *dirname, int len,
 541         const struct path_simplify *simplify)
 542 {
 543         /* The "len-1" is to strip the final '/' */
 544         switch (directory_exists_in_index(dirname, len-1)) {
 545         case index_directory:
 546                 return recurse_into_directory;
 547
 548         case index_gitdir:
 549                 if (dir->flags & DIR_SHOW_OTHER_DIRECTORIES)
 550                         return ignore_directory;
 551                 return show_directory;
 552
 553         case index_nonexistent:
 554                 if (dir->flags & DIR_SHOW_OTHER_DIRECTORIES)
 555                         break;
 556                 if (!(dir->flags & DIR_NO_GITLINKS)) {
 557                         unsigned char sha1[20];
 558                         if (resolve_gitlink_ref(dirname, "HEAD", sha1) == 0)
 559                                 return show_directory;
 560                 }
 561                 return recurse_into_directory;
 562         }
 563
 564         /* This is the "show_other_directories" case */
 565         if (!(dir->flags & DIR_HIDE_EMPTY_DIRECTORIES))
 566                 return show_directory;
 567         if (!read_directory_recursive(dir, dirname, len, 1, simplify))
 568                 return ignore_directory;
 569         return show_directory;
 570 }
 571
 572 /*
 573  * This is an inexact early pruning of any recursive directory
 574  * reading - if the path cannot possibly be in the pathspec,
 575  * return true, and we'll skip it early.
 576  */
 577 static int simplify_away(const char *path, int pathlen, const struct path_simplify *simplify)
 578 {
 579         if (simplify) {
 580                 for (;;) {
 581                         const char *match = simplify->path;
 582                         int len = simplify->len;
 583
 584                         if (!match)
 585                                 break;
 586                         if (len > pathlen)
 587                                 len = pathlen;
 588                         if (!memcmp(path, match, len))
 589                                 return 0;
 590                         simplify++;
 591                 }
 592                 return 1;
 593         }
 594         return 0;
 595 }
 596
 597 /*
 598  * This function tells us whether an excluded path matches a
 599  * list of "interesting" pathspecs. That is, whether a path matched
 600  * by any of the pathspecs could possibly be ignored by excluding
 601  * the specified path. This can happen if:
 602  *
 603  *   1. the path is mentioned explicitly in the pathspec
 604  *
 605  *   2. the path is a directory prefix of some element in the
 606  *      pathspec
 607  */
 608 static int exclude_matches_pathspec(const char *path, int len,
 609                 const struct path_simplify *simplify)
 610 {
 611         if (simplify) {
 612                 for (; simplify->path; simplify++) {
 613                         if (len == simplify->len
 614                             && !memcmp(path, simplify->path, len))
 615                                 return 1;
 616                         if (len < simplify->len
 617                             && simplify->path[len] == '/'
 618                             && !memcmp(path, simplify->path, len))
 619                                 return 1;
 620                 }
 621         }
 622         return 0;
 623 }
 624
 625 static int get_index_dtype(const char *path, int len)
 626 {
 627         int pos;
 628         struct cache_entry *ce;
 629
 630         ce = cache_name_exists(path, len, 0);
 631         if (ce) {
 632                 if (!ce_uptodate(ce))
 633                         return DT_UNKNOWN;
 634                 if (S_ISGITLINK(ce->ce_mode))
 635                         return DT_DIR;
 636                 /*
 637                  * Nobody actually cares about the
 638                  * difference between DT_LNK and DT_REG
 639                  */
 640                 return DT_REG;
 641         }
 642
 643         /* Try to look it up as a directory */
 644         pos = cache_name_pos(path, len);
 645         if (pos >= 0)
 646                 return DT_UNKNOWN;
 647         pos = -pos-1;
 648         while (pos < active_nr) {
 649                 ce = active_cache[pos++];
 650                 if (strncmp(ce->name, path, len))
 651                         break;
 652                 if (ce->name[len] > '/')
 653                         break;
 654                 if (ce->name[len] < '/')
 655                         continue;
 656                 if (!ce_uptodate(ce))
 657                         break;  /* continue? */
 658                 return DT_DIR;
 659         }
 660         return DT_UNKNOWN;
 661 }
 662
 663 static int get_dtype(struct dirent *de, const char *path, int len)
 664 {
 665         int dtype = de ? DTYPE(de) : DT_UNKNOWN;
 666         struct stat st;
 667
 668         if (dtype != DT_UNKNOWN)
 669                 return dtype;
 670         dtype = get_index_dtype(path, len);
 671         if (dtype != DT_UNKNOWN)
 672                 return dtype;
 673         if (lstat(path, &st))
 674                 return dtype;
 675         if (S_ISREG(st.st_mode))
 676                 return DT_REG;
 677         if (S_ISDIR(st.st_mode))
 678                 return DT_DIR;
 679         if (S_ISLNK(st.st_mode))
 680                 return DT_LNK;
 681         return dtype;
 682 }
 683
 684 enum path_treatment {
 685         path_ignored,
 686         path_handled,
 687         path_recurse
 688 };
 689
 690 static enum path_treatment treat_one_path(struct dir_struct *dir,
 691                                           char *path, int *len,
 692                                           const struct path_simplify *simplify,
 693                                           int dtype, struct dirent *de)
 694 {
 695         int exclude = excluded(dir, path, &dtype);
 696         if (exclude && (dir->flags & DIR_COLLECT_IGNORED)
 697             && exclude_matches_pathspec(path, *len, simplify))
 698                 dir_add_ignored(dir, path, *len);
 699
 700         /*
 701          * Excluded? If we don't explicitly want to show
 702          * ignored files, ignore it
 703          */
 704         if (exclude && !(dir->flags & DIR_SHOW_IGNORED))
 705                 return path_ignored;
 706
 707         if (dtype == DT_UNKNOWN)
 708                 dtype = get_dtype(de, path, *len);
 709
 710         /*
 711          * Do we want to see just the ignored files?
 712          * We still need to recurse into directories,
 713          * even if we don't ignore them, since the
 714          * directory may contain files that we do..
 715          */
 716         if (!exclude && (dir->flags & DIR_SHOW_IGNORED)) {
 717                 if (dtype != DT_DIR)
 718                         return path_ignored;
 719         }
 720
 721         switch (dtype) {
 722         default:
 723                 return path_ignored;
 724         case DT_DIR:
 725                 memcpy(path + *len, "/", 2);
 726                 (*len)++;
 727                 switch (treat_directory(dir, path, *len, simplify)) {
 728                 case show_directory:
 729                         if (exclude != !!(dir->flags
 730                                           & DIR_SHOW_IGNORED))
 731                                 return path_ignored;
 732                         break;
 733                 case recurse_into_directory:
 734                         return path_recurse;
 735                 case ignore_directory:
 736                         return path_ignored;
 737                 }
 738                 break;
 739         case DT_REG:
 740         case DT_LNK:
 741                 break;
 742         }
 743         return path_handled;
 744 }
 745
 746 static enum path_treatment treat_path(struct dir_struct *dir,
 747                                       struct dirent *de,
 748                                       char *path, int path_max,
 749                                       int baselen,
 750                                       const struct path_simplify *simplify,
 751                                       int *len)
 752 {
 753         int dtype;
 754
 755         if (is_dot_or_dotdot(de->d_name) || !strcmp(de->d_name, ".git"))
 756                 return path_ignored;
 757         *len = strlen(de->d_name);
 758         /* Ignore overly long pathnames! */
 759         if (*len + baselen + 8 > path_max)
 760                 return path_ignored;
 761         memcpy(path + baselen, de->d_name, *len + 1);
 762         *len += baselen;
 763         if (simplify_away(path, *len, simplify))
 764                 return path_ignored;
 765
 766         dtype = DTYPE(de);
 767         return treat_one_path(dir, path, len, simplify, dtype, de);
 768 }
 769
 770 /*
 771  * Read a directory tree. We currently ignore anything but
 772  * directories, regular files and symlinks. That's because git
 773  * doesn't handle them at all yet. Maybe that will change some
 774  * day.
 775  *
 776  * Also, we ignore the name ".git" (even if it is not a directory).
 777  * That likely will not change.
 778  */
 779 static int read_directory_recursive(struct dir_struct *dir,
 780                                     const char *base, int baselen,
 781                                     int check_only,
 782                                     const struct path_simplify *simplify)
 783 {
 784         DIR *fdir = opendir(*base ? base : ".");
 785         int contents = 0;
 786
 787         if (fdir) {
 788                 struct dirent *de;
 789                 char path[PATH_MAX + 1];
 790                 memcpy(path, base, baselen);
 791
 792                 while ((de = readdir(fdir)) != NULL) {
 793                         int len;
 794                         switch (treat_path(dir, de, path, sizeof(path),
 795                                            baselen, simplify, &len)) {
 796                         case path_recurse:
 797                                 contents += read_directory_recursive
 798                                         (dir, path, len, 0, simplify);
 799                                 continue;
 800                         case path_ignored:
 801                                 continue;
 802                         case path_handled:
 803                                 break;
 804                         }
 805                         contents++;
 806                         if (check_only)
 807                                 goto exit_early;
 808                         else
 809                                 dir_add_name(dir, path, len);
 810                 }
 811 exit_early:
 812                 closedir(fdir);
 813         }
 814
 815         return contents;
 816 }
 817
 818 static int cmp_name(const void *p1, const void *p2)
 819 {
 820         const struct dir_entry *e1 = *(const struct dir_entry **)p1;
 821         const struct dir_entry *e2 = *(const struct dir_entry **)p2;
 822
 823         return cache_name_compare(e1->name, e1->len,
 824                                   e2->name, e2->len);
 825 }
 826
 827 /*
 828  * Return the length of the "simple" part of a path match limiter.
 829  */
 830 static int simple_length(const char *match)
 831 {
 832         int len = -1;
 833
 834         for (;;) {
 835                 unsigned char c = *match++;
 836                 len++;
 837                 if (c == '\0' || is_glob_special(c))
 838                         return len;
 839         }
 840 }
 841
 842 static struct path_simplify *create_simplify(const char **pathspec)
 843 {
 844         int nr, alloc = 0;
 845         struct path_simplify *simplify = NULL;
 846
 847         if (!pathspec)
 848                 return NULL;
 849
 850         for (nr = 0 ; ; nr++) {
 851                 const char *match;
 852                 if (nr >= alloc) {
 853                         alloc = alloc_nr(alloc);
 854                         simplify = xrealloc(simplify, alloc * sizeof(*simplify));
 855                 }
 856                 match = *pathspec++;
 857                 if (!match)
 858                         break;
 859                 simplify[nr].path = match;
 860                 simplify[nr].len = simple_length(match);
 861         }
 862         simplify[nr].path = NULL;
 863         simplify[nr].len = 0;
 864         return simplify;
 865 }
 866
 867 static void free_simplify(struct path_simplify *simplify)
 868 {
 869         free(simplify);
 870 }
 871
 872 static int treat_leading_path(struct dir_struct *dir,
 873                               const char *path, int len,
 874                               const struct path_simplify *simplify)
 875 {
 876         char pathbuf[PATH_MAX];
 877         int baselen, blen;
 878         const char *cp;
 879
 880         while (len && path[len - 1] == '/')
 881                 len--;
 882         if (!len)
 883                 return 1;
 884         baselen = 0;
 885         while (1) {
 886                 cp = path + baselen + !!baselen;
 887                 cp = memchr(cp, '/', path + len - cp);
 888                 if (!cp)
 889                         baselen = len;
 890                 else
 891                         baselen = cp - path;
 892                 memcpy(pathbuf, path, baselen);
 893                 pathbuf[baselen] = '\0';
 894                 if (!is_directory(pathbuf))
 895                         return 0;
 896                 if (simplify_away(pathbuf, baselen, simplify))
 897                         return 0;
 898                 blen = baselen;
 899                 if (treat_one_path(dir, pathbuf, &blen, simplify,
 900                                    DT_DIR, NULL) == path_ignored)
 901                         return 0; /* do not recurse into it */
 902                 if (len <= baselen)
 903                         return 1; /* finished checking */
 904         }
 905 }
 906
 907 int read_directory(struct dir_struct *dir, const char *path, int len, const char **pathspec)
 908 {
 909         struct path_simplify *simplify;
 910
 911         if (has_symlink_leading_path(path, len))
 912                 return dir->nr;
 913
 914         simplify = create_simplify(pathspec);
 915         if (!len || treat_leading_path(dir, path, len, simplify))
 916                 read_directory_recursive(dir, path, len, 0, simplify);
 917         free_simplify(simplify);
 918         qsort(dir->entries, dir->nr, sizeof(struct dir_entry *), cmp_name);
 919         qsort(dir->ignored, dir->ignored_nr, sizeof(struct dir_entry *), cmp_name);
 920         return dir->nr;
 921 }
 922
 923 int file_exists(const char *f)
 924 {
 925         struct stat sb;
 926         return lstat(f, &sb) == 0;
 927 }
 928
 929 /*
 930  * get_relative_cwd() gets the prefix of the current working directory
 931  * relative to 'dir'.  If we are not inside 'dir', it returns NULL.
 932  *
 933  * As a convenience, it also returns NULL if 'dir' is already NULL.  The
 934  * reason for this behaviour is that it is natural for functions returning
 935  * directory names to return NULL to say "this directory does not exist"
 936  * or "this directory is invalid".  These cases are usually handled the
 937  * same as if the cwd is not inside 'dir' at all, so get_relative_cwd()
 938  * returns NULL for both of them.
 939  *
 940  * Most notably, get_relative_cwd(buffer, size, get_git_work_tree())
 941  * unifies the handling of "outside work tree" with "no work tree at all".
 942  */
 943 char *get_relative_cwd(char *buffer, int size, const char *dir)
 944 {
 945         char *cwd = buffer;
 946
 947         if (!dir)
 948                 return NULL;
 949         if (!getcwd(buffer, size))
 950                 die_errno("can't find the current directory");
 951
 952         if (!is_absolute_path(dir))
 953                 dir = make_absolute_path(dir);
 954
 955         while (*dir && *dir == *cwd) {
 956                 dir++;
 957                 cwd++;
 958         }
 959         if (*dir)
 960                 return NULL;
 961         switch (*cwd) {
 962         case '\0':
 963                 return cwd;
 964         case '/':
 965                 return cwd + 1;
 966         default:
 967                 return NULL;
 968         }
 969 }
 970
 971 int is_inside_dir(const char *dir)
 972 {
 973         char buffer[PATH_MAX];
 974         return get_relative_cwd(buffer, sizeof(buffer), dir) != NULL;
 975 }
 976
 977 int is_empty_dir(const char *path)
 978 {
 979         DIR *dir = opendir(path);
 980         struct dirent *e;
 981         int ret = 1;
 982
 983         if (!dir)
 984                 return 0;
 985
 986         while ((e = readdir(dir)) != NULL)
 987                 if (!is_dot_or_dotdot(e->d_name)) {
 988                         ret = 0;
 989                         break;
 990                 }
 991
 992         closedir(dir);
 993         return ret;
 994 }
 995
 996 int remove_dir_recursively(struct strbuf *path, int flag)
 997 {
 998         DIR *dir;
 999         struct dirent *e;
1000         int ret = 0, original_len = path->len, len;
1001         int only_empty = (flag & REMOVE_DIR_EMPTY_ONLY);
1002         unsigned char submodule_head[20];
1003
1004         if ((flag & REMOVE_DIR_KEEP_NESTED_GIT) &&
1005             !resolve_gitlink_ref(path->buf, "HEAD", submodule_head))
1006                 /* Do not descend and nuke a nested git work tree. */
1007                 return 0;
1008
1009         dir = opendir(path->buf);
1010         if (!dir)
1011                 return -1;
1012         if (path->buf[original_len - 1] != '/')
1013                 strbuf_addch(path, '/');
1014
1015         len = path->len;
1016         while ((e = readdir(dir)) != NULL) {
1017                 struct stat st;
1018                 if (is_dot_or_dotdot(e->d_name))
1019                         continue;
1020
1021                 strbuf_setlen(path, len);
1022                 strbuf_addstr(path, e->d_name);
1023                 if (lstat(path->buf, &st))
1024                         ; /* fall thru */
1025                 else if (S_ISDIR(st.st_mode)) {
1026                         if (!remove_dir_recursively(path, only_empty))
1027                                 continue; /* happy */
1028                 } else if (!only_empty && !unlink(path->buf))
1029                         continue; /* happy, too */
1030
1031                 /* path too long, stat fails, or non-directory still exists */
1032                 ret = -1;
1033                 break;
1034         }
1035         closedir(dir);
1036
1037         strbuf_setlen(path, original_len);
1038         if (!ret)
1039                 ret = rmdir(path->buf);
1040         return ret;
1041 }
1042
1043 void setup_standard_excludes(struct dir_struct *dir)
1044 {
1045         const char *path;
1046
1047         dir->exclude_per_dir = ".gitignore";
1048         path = git_path("info/exclude");
1049         if (!access(path, R_OK))
1050                 add_excludes_from_file(dir, path);
1051         if (excludes_file && !access(excludes_file, R_OK))
1052                 add_excludes_from_file(dir, excludes_file);
1053 }
1054
1055 int remove_path(const char *name)
1056 {
1057         char *slash;
1058
1059         if (unlink(name) && errno != ENOENT)
1060                 return -1;
1061
1062         slash = strrchr(name, '/');
1063         if (slash) {
1064                 char *dirs = xstrdup(name);
1065                 slash = dirs + (slash - name);
1066                 do {
1067                         *slash = '\0';
1068                 } while (rmdir(dirs) == 0 && (slash = strrchr(dirs, '/')));
1069                 free(dirs);
1070         }
1071         return 0;
1072 }
1073