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         prefix = slash - path + 1;
  35         while ((next = *++pathspec) != NULL) {
  36                 int len = strlen(next);
  37                 if (len >= prefix && !memcmp(path, next, prefix))
  38                         continue;
  39                 len = prefix - 1;
  40                 for (;;) {
  41                         if (!len)
  42                                 return 0;
  43                         if (next[--len] != '/')
  44                                 continue;
  45                         if (memcmp(path, next, len+1))
  46                                 continue;
  47                         prefix = len + 1;
  48                         break;
  49                 }
  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 int add_excludes_from_file_1(const char *fname,
 204                                     const char *base,
 205                                     int baselen,
 206                                     char **buf_p,
 207                                     struct exclude_list *which)
 208 {
 209         struct stat st;
 210         int fd, i;
 211         size_t size;
 212         char *buf, *entry;
 213
 214         fd = open(fname, O_RDONLY);
 215         if (fd < 0 || fstat(fd, &st) < 0)
 216                 goto err;
 217         size = xsize_t(st.st_size);
 218         if (size == 0) {
 219                 close(fd);
 220                 return 0;
 221         }
 222         buf = xmalloc(size+1);
 223         if (read_in_full(fd, buf, size) != size)
 224         {
 225                 free(buf);
 226                 goto err;
 227         }
 228         close(fd);
 229
 230         if (buf_p)
 231                 *buf_p = buf;
 232         buf[size++] = '\n';
 233         entry = buf;
 234         for (i = 0; i < size; i++) {
 235                 if (buf[i] == '\n') {
 236                         if (entry != buf + i && entry[0] != '#') {
 237                                 buf[i - (i && buf[i-1] == '\r')] = 0;
 238                                 add_exclude(entry, base, baselen, which);
 239                         }
 240                         entry = buf + i + 1;
 241                 }
 242         }
 243         return 0;
 244
 245  err:
 246         if (0 <= fd)
 247                 close(fd);
 248         return -1;
 249 }
 250
 251 void add_excludes_from_file(struct dir_struct *dir, const char *fname)
 252 {
 253         if (add_excludes_from_file_1(fname, "", 0, NULL,
 254                                      &dir->exclude_list[EXC_FILE]) < 0)
 255                 die("cannot use %s as an exclude file", fname);
 256 }
 257
 258 static void prep_exclude(struct dir_struct *dir, const char *base, int baselen)
 259 {
 260         struct exclude_list *el;
 261         struct exclude_stack *stk = NULL;
 262         int current;
 263
 264         if ((!dir->exclude_per_dir) ||
 265             (baselen + strlen(dir->exclude_per_dir) >= PATH_MAX))
 266                 return; /* too long a path -- ignore */
 267
 268         /* Pop the ones that are not the prefix of the path being checked. */
 269         el = &dir->exclude_list[EXC_DIRS];
 270         while ((stk = dir->exclude_stack) != NULL) {
 271                 if (stk->baselen <= baselen &&
 272                     !strncmp(dir->basebuf, base, stk->baselen))
 273                         break;
 274                 dir->exclude_stack = stk->prev;
 275                 while (stk->exclude_ix < el->nr)
 276                         free(el->excludes[--el->nr]);
 277                 free(stk->filebuf);
 278                 free(stk);
 279         }
 280
 281         /* Read from the parent directories and push them down. */
 282         current = stk ? stk->baselen : -1;
 283         while (current < baselen) {
 284                 struct exclude_stack *stk = xcalloc(1, sizeof(*stk));
 285                 const char *cp;
 286
 287                 if (current < 0) {
 288                         cp = base;
 289                         current = 0;
 290                 }
 291                 else {
 292                         cp = strchr(base + current + 1, '/');
 293                         if (!cp)
 294                                 die("oops in prep_exclude");
 295                         cp++;
 296                 }
 297                 stk->prev = dir->exclude_stack;
 298                 stk->baselen = cp - base;
 299                 stk->exclude_ix = el->nr;
 300                 memcpy(dir->basebuf + current, base + current,
 301                        stk->baselen - current);
 302                 strcpy(dir->basebuf + stk->baselen, dir->exclude_per_dir);
 303                 add_excludes_from_file_1(dir->basebuf,
 304                                          dir->basebuf, stk->baselen,
 305                                          &stk->filebuf, el);
 306                 dir->exclude_stack = stk;
 307                 current = stk->baselen;
 308         }
 309         dir->basebuf[baselen] = '\0';
 310 }
 311
 312 /* Scan the list and let the last match determine the fate.
 313  * Return 1 for exclude, 0 for include and -1 for undecided.
 314  */
 315 static int excluded_1(const char *pathname,
 316                       int pathlen, const char *basename, int *dtype,
 317                       struct exclude_list *el)
 318 {
 319         int i;
 320
 321         if (el->nr) {
 322                 for (i = el->nr - 1; 0 <= i; i--) {
 323                         struct exclude *x = el->excludes[i];
 324                         const char *exclude = x->pattern;
 325                         int to_exclude = x->to_exclude;
 326
 327                         if (x->flags & EXC_FLAG_MUSTBEDIR) {
 328                                 if (*dtype == DT_UNKNOWN)
 329                                         *dtype = get_dtype(NULL, pathname, pathlen);
 330                                 if (*dtype != DT_DIR)
 331                                         continue;
 332                         }
 333
 334                         if (x->flags & EXC_FLAG_NODIR) {
 335                                 /* match basename */
 336                                 if (x->flags & EXC_FLAG_NOWILDCARD) {
 337                                         if (!strcmp(exclude, basename))
 338                                                 return to_exclude;
 339                                 } else if (x->flags & EXC_FLAG_ENDSWITH) {
 340                                         if (x->patternlen - 1 <= pathlen &&
 341                                             !strcmp(exclude + 1, pathname + pathlen - x->patternlen + 1))
 342                                                 return to_exclude;
 343                                 } else {
 344                                         if (fnmatch(exclude, basename, 0) == 0)
 345                                                 return to_exclude;
 346                                 }
 347                         }
 348                         else {
 349                                 /* match with FNM_PATHNAME:
 350                                  * exclude has base (baselen long) implicitly
 351                                  * in front of it.
 352                                  */
 353                                 int baselen = x->baselen;
 354                                 if (*exclude == '/')
 355                                         exclude++;
 356
 357                                 if (pathlen < baselen ||
 358                                     (baselen && pathname[baselen-1] != '/') ||
 359                                     strncmp(pathname, x->base, baselen))
 360                                     continue;
 361
 362                                 if (x->flags & EXC_FLAG_NOWILDCARD) {
 363                                         if (!strcmp(exclude, pathname + baselen))
 364                                                 return to_exclude;
 365                                 } else {
 366                                         if (fnmatch(exclude, pathname+baselen,
 367                                                     FNM_PATHNAME) == 0)
 368                                             return to_exclude;
 369                                 }
 370                         }
 371                 }
 372         }
 373         return -1; /* undecided */
 374 }
 375
 376 int excluded(struct dir_struct *dir, const char *pathname, int *dtype_p)
 377 {
 378         int pathlen = strlen(pathname);
 379         int st;
 380         const char *basename = strrchr(pathname, '/');
 381         basename = (basename) ? basename+1 : pathname;
 382
 383         prep_exclude(dir, pathname, basename-pathname);
 384         for (st = EXC_CMDL; st <= EXC_FILE; st++) {
 385                 switch (excluded_1(pathname, pathlen, basename,
 386                                    dtype_p, &dir->exclude_list[st])) {
 387                 case 0:
 388                         return 0;
 389                 case 1:
 390                         return 1;
 391                 }
 392         }
 393         return 0;
 394 }
 395
 396 static struct dir_entry *dir_entry_new(const char *pathname, int len)
 397 {
 398         struct dir_entry *ent;
 399
 400         ent = xmalloc(sizeof(*ent) + len + 1);
 401         ent->len = len;
 402         memcpy(ent->name, pathname, len);
 403         ent->name[len] = 0;
 404         return ent;
 405 }
 406
 407 static struct dir_entry *dir_add_name(struct dir_struct *dir, const char *pathname, int len)
 408 {
 409         if (cache_name_exists(pathname, len, ignore_case))
 410                 return NULL;
 411
 412         ALLOC_GROW(dir->entries, dir->nr+1, dir->alloc);
 413         return dir->entries[dir->nr++] = dir_entry_new(pathname, len);
 414 }
 415
 416 static struct dir_entry *dir_add_ignored(struct dir_struct *dir, const char *pathname, int len)
 417 {
 418         if (!cache_name_is_other(pathname, len))
 419                 return NULL;
 420
 421         ALLOC_GROW(dir->ignored, dir->ignored_nr+1, dir->ignored_alloc);
 422         return dir->ignored[dir->ignored_nr++] = dir_entry_new(pathname, len);
 423 }
 424
 425 enum exist_status {
 426         index_nonexistent = 0,
 427         index_directory,
 428         index_gitdir,
 429 };
 430
 431 /*
 432  * The index sorts alphabetically by entry name, which
 433  * means that a gitlink sorts as '\0' at the end, while
 434  * a directory (which is defined not as an entry, but as
 435  * the files it contains) will sort with the '/' at the
 436  * end.
 437  */
 438 static enum exist_status directory_exists_in_index(const char *dirname, int len)
 439 {
 440         int pos = cache_name_pos(dirname, len);
 441         if (pos < 0)
 442                 pos = -pos-1;
 443         while (pos < active_nr) {
 444                 struct cache_entry *ce = active_cache[pos++];
 445                 unsigned char endchar;
 446
 447                 if (strncmp(ce->name, dirname, len))
 448                         break;
 449                 endchar = ce->name[len];
 450                 if (endchar > '/')
 451                         break;
 452                 if (endchar == '/')
 453                         return index_directory;
 454                 if (!endchar && S_ISGITLINK(ce->ce_mode))
 455                         return index_gitdir;
 456         }
 457         return index_nonexistent;
 458 }
 459
 460 /*
 461  * When we find a directory when traversing the filesystem, we
 462  * have three distinct cases:
 463  *
 464  *  - ignore it
 465  *  - see it as a directory
 466  *  - recurse into it
 467  *
 468  * and which one we choose depends on a combination of existing
 469  * git index contents and the flags passed into the directory
 470  * traversal routine.
 471  *
 472  * Case 1: If we *already* have entries in the index under that
 473  * directory name, we always recurse into the directory to see
 474  * all the files.
 475  *
 476  * Case 2: If we *already* have that directory name as a gitlink,
 477  * we always continue to see it as a gitlink, regardless of whether
 478  * there is an actual git directory there or not (it might not
 479  * be checked out as a subproject!)
 480  *
 481  * Case 3: if we didn't have it in the index previously, we
 482  * have a few sub-cases:
 483  *
 484  *  (a) if "show_other_directories" is true, we show it as
 485  *      just a directory, unless "hide_empty_directories" is
 486  *      also true and the directory is empty, in which case
 487  *      we just ignore it entirely.
 488  *  (b) if it looks like a git directory, and we don't have
 489  *      'no_gitlinks' set we treat it as a gitlink, and show it
 490  *      as a directory.
 491  *  (c) otherwise, we recurse into it.
 492  */
 493 enum directory_treatment {
 494         show_directory,
 495         ignore_directory,
 496         recurse_into_directory,
 497 };
 498
 499 static enum directory_treatment treat_directory(struct dir_struct *dir,
 500         const char *dirname, int len,
 501         const struct path_simplify *simplify)
 502 {
 503         /* The "len-1" is to strip the final '/' */
 504         switch (directory_exists_in_index(dirname, len-1)) {
 505         case index_directory:
 506                 return recurse_into_directory;
 507
 508         case index_gitdir:
 509                 if (dir->flags & DIR_SHOW_OTHER_DIRECTORIES)
 510                         return ignore_directory;
 511                 return show_directory;
 512
 513         case index_nonexistent:
 514                 if (dir->flags & DIR_SHOW_OTHER_DIRECTORIES)
 515                         break;
 516                 if (!(dir->flags & DIR_NO_GITLINKS)) {
 517                         unsigned char sha1[20];
 518                         if (resolve_gitlink_ref(dirname, "HEAD", sha1) == 0)
 519                                 return show_directory;
 520                 }
 521                 return recurse_into_directory;
 522         }
 523
 524         /* This is the "show_other_directories" case */
 525         if (!(dir->flags & DIR_HIDE_EMPTY_DIRECTORIES))
 526                 return show_directory;
 527         if (!read_directory_recursive(dir, dirname, len, 1, simplify))
 528                 return ignore_directory;
 529         return show_directory;
 530 }
 531
 532 /*
 533  * This is an inexact early pruning of any recursive directory
 534  * reading - if the path cannot possibly be in the pathspec,
 535  * return true, and we'll skip it early.
 536  */
 537 static int simplify_away(const char *path, int pathlen, const struct path_simplify *simplify)
 538 {
 539         if (simplify) {
 540                 for (;;) {
 541                         const char *match = simplify->path;
 542                         int len = simplify->len;
 543
 544                         if (!match)
 545                                 break;
 546                         if (len > pathlen)
 547                                 len = pathlen;
 548                         if (!memcmp(path, match, len))
 549                                 return 0;
 550                         simplify++;
 551                 }
 552                 return 1;
 553         }
 554         return 0;
 555 }
 556
 557 static int in_pathspec(const char *path, int len, const struct path_simplify *simplify)
 558 {
 559         if (simplify) {
 560                 for (; simplify->path; simplify++) {
 561                         if (len == simplify->len
 562                             && !memcmp(path, simplify->path, len))
 563                                 return 1;
 564                 }
 565         }
 566         return 0;
 567 }
 568
 569 static int get_index_dtype(const char *path, int len)
 570 {
 571         int pos;
 572         struct cache_entry *ce;
 573
 574         ce = cache_name_exists(path, len, 0);
 575         if (ce) {
 576                 if (!ce_uptodate(ce))
 577                         return DT_UNKNOWN;
 578                 if (S_ISGITLINK(ce->ce_mode))
 579                         return DT_DIR;
 580                 /*
 581                  * Nobody actually cares about the
 582                  * difference between DT_LNK and DT_REG
 583                  */
 584                 return DT_REG;
 585         }
 586
 587         /* Try to look it up as a directory */
 588         pos = cache_name_pos(path, len);
 589         if (pos >= 0)
 590                 return DT_UNKNOWN;
 591         pos = -pos-1;
 592         while (pos < active_nr) {
 593                 ce = active_cache[pos++];
 594                 if (strncmp(ce->name, path, len))
 595                         break;
 596                 if (ce->name[len] > '/')
 597                         break;
 598                 if (ce->name[len] < '/')
 599                         continue;
 600                 if (!ce_uptodate(ce))
 601                         break;  /* continue? */
 602                 return DT_DIR;
 603         }
 604         return DT_UNKNOWN;
 605 }
 606
 607 static int get_dtype(struct dirent *de, const char *path, int len)
 608 {
 609         int dtype = de ? DTYPE(de) : DT_UNKNOWN;
 610         struct stat st;
 611
 612         if (dtype != DT_UNKNOWN)
 613                 return dtype;
 614         dtype = get_index_dtype(path, len);
 615         if (dtype != DT_UNKNOWN)
 616                 return dtype;
 617         if (lstat(path, &st))
 618                 return dtype;
 619         if (S_ISREG(st.st_mode))
 620                 return DT_REG;
 621         if (S_ISDIR(st.st_mode))
 622                 return DT_DIR;
 623         if (S_ISLNK(st.st_mode))
 624                 return DT_LNK;
 625         return dtype;
 626 }
 627
 628 /*
 629  * Read a directory tree. We currently ignore anything but
 630  * directories, regular files and symlinks. That's because git
 631  * doesn't handle them at all yet. Maybe that will change some
 632  * day.
 633  *
 634  * Also, we ignore the name ".git" (even if it is not a directory).
 635  * That likely will not change.
 636  */
 637 static int read_directory_recursive(struct dir_struct *dir, const char *base, int baselen, int check_only, const struct path_simplify *simplify)
 638 {
 639         DIR *fdir = opendir(*base ? base : ".");
 640         int contents = 0;
 641
 642         if (fdir) {
 643                 struct dirent *de;
 644                 char path[PATH_MAX + 1];
 645                 memcpy(path, base, baselen);
 646
 647                 while ((de = readdir(fdir)) != NULL) {
 648                         int len, dtype;
 649                         int exclude;
 650
 651                         if (is_dot_or_dotdot(de->d_name) ||
 652                              !strcmp(de->d_name, ".git"))
 653                                 continue;
 654                         len = strlen(de->d_name);
 655                         /* Ignore overly long pathnames! */
 656                         if (len + baselen + 8 > sizeof(path))
 657                                 continue;
 658                         memcpy(path + baselen, de->d_name, len+1);
 659                         len = baselen + len;
 660                         if (simplify_away(path, len, simplify))
 661                                 continue;
 662
 663                         dtype = DTYPE(de);
 664                         exclude = excluded(dir, path, &dtype);
 665                         if (exclude && (dir->flags & DIR_COLLECT_IGNORED)
 666                             && in_pathspec(path, len, simplify))
 667                                 dir_add_ignored(dir, path,len);
 668
 669                         /*
 670                          * Excluded? If we don't explicitly want to show
 671                          * ignored files, ignore it
 672                          */
 673                         if (exclude && !(dir->flags & DIR_SHOW_IGNORED))
 674                                 continue;
 675
 676                         if (dtype == DT_UNKNOWN)
 677                                 dtype = get_dtype(de, path, len);
 678
 679                         /*
 680                          * Do we want to see just the ignored files?
 681                          * We still need to recurse into directories,
 682                          * even if we don't ignore them, since the
 683                          * directory may contain files that we do..
 684                          */
 685                         if (!exclude && (dir->flags & DIR_SHOW_IGNORED)) {
 686                                 if (dtype != DT_DIR)
 687                                         continue;
 688                         }
 689
 690                         switch (dtype) {
 691                         default:
 692                                 continue;
 693                         case DT_DIR:
 694                                 memcpy(path + len, "/", 2);
 695                                 len++;
 696                                 switch (treat_directory(dir, path, len, simplify)) {
 697                                 case show_directory:
 698                                         if (exclude != !!(dir->flags
 699                                                         & DIR_SHOW_IGNORED))
 700                                                 continue;
 701                                         break;
 702                                 case recurse_into_directory:
 703                                         contents += read_directory_recursive(dir,
 704                                                 path, len, 0, simplify);
 705                                         continue;
 706                                 case ignore_directory:
 707                                         continue;
 708                                 }
 709                                 break;
 710                         case DT_REG:
 711                         case DT_LNK:
 712                                 break;
 713                         }
 714                         contents++;
 715                         if (check_only)
 716                                 goto exit_early;
 717                         else
 718                                 dir_add_name(dir, path, len);
 719                 }
 720 exit_early:
 721                 closedir(fdir);
 722         }
 723
 724         return contents;
 725 }
 726
 727 static int cmp_name(const void *p1, const void *p2)
 728 {
 729         const struct dir_entry *e1 = *(const struct dir_entry **)p1;
 730         const struct dir_entry *e2 = *(const struct dir_entry **)p2;
 731
 732         return cache_name_compare(e1->name, e1->len,
 733                                   e2->name, e2->len);
 734 }
 735
 736 /*
 737  * Return the length of the "simple" part of a path match limiter.
 738  */
 739 static int simple_length(const char *match)
 740 {
 741         int len = -1;
 742
 743         for (;;) {
 744                 unsigned char c = *match++;
 745                 len++;
 746                 if (c == '\0' || is_glob_special(c))
 747                         return len;
 748         }
 749 }
 750
 751 static struct path_simplify *create_simplify(const char **pathspec)
 752 {
 753         int nr, alloc = 0;
 754         struct path_simplify *simplify = NULL;
 755
 756         if (!pathspec)
 757                 return NULL;
 758
 759         for (nr = 0 ; ; nr++) {
 760                 const char *match;
 761                 if (nr >= alloc) {
 762                         alloc = alloc_nr(alloc);
 763                         simplify = xrealloc(simplify, alloc * sizeof(*simplify));
 764                 }
 765                 match = *pathspec++;
 766                 if (!match)
 767                         break;
 768                 simplify[nr].path = match;
 769                 simplify[nr].len = simple_length(match);
 770         }
 771         simplify[nr].path = NULL;
 772         simplify[nr].len = 0;
 773         return simplify;
 774 }
 775
 776 static void free_simplify(struct path_simplify *simplify)
 777 {
 778         free(simplify);
 779 }
 780
 781 int read_directory(struct dir_struct *dir, const char *path, int len, const char **pathspec)
 782 {
 783         struct path_simplify *simplify;
 784
 785         if (has_symlink_leading_path(path, len))
 786                 return dir->nr;
 787
 788         simplify = create_simplify(pathspec);
 789         read_directory_recursive(dir, path, len, 0, simplify);
 790         free_simplify(simplify);
 791         qsort(dir->entries, dir->nr, sizeof(struct dir_entry *), cmp_name);
 792         qsort(dir->ignored, dir->ignored_nr, sizeof(struct dir_entry *), cmp_name);
 793         return dir->nr;
 794 }
 795
 796 int file_exists(const char *f)
 797 {
 798         struct stat sb;
 799         return lstat(f, &sb) == 0;
 800 }
 801
 802 /*
 803  * get_relative_cwd() gets the prefix of the current working directory
 804  * relative to 'dir'.  If we are not inside 'dir', it returns NULL.
 805  *
 806  * As a convenience, it also returns NULL if 'dir' is already NULL.  The
 807  * reason for this behaviour is that it is natural for functions returning
 808  * directory names to return NULL to say "this directory does not exist"
 809  * or "this directory is invalid".  These cases are usually handled the
 810  * same as if the cwd is not inside 'dir' at all, so get_relative_cwd()
 811  * returns NULL for both of them.
 812  *
 813  * Most notably, get_relative_cwd(buffer, size, get_git_work_tree())
 814  * unifies the handling of "outside work tree" with "no work tree at all".
 815  */
 816 char *get_relative_cwd(char *buffer, int size, const char *dir)
 817 {
 818         char *cwd = buffer;
 819
 820         if (!dir)
 821                 return NULL;
 822         if (!getcwd(buffer, size))
 823                 die_errno("can't find the current directory");
 824
 825         if (!is_absolute_path(dir))
 826                 dir = make_absolute_path(dir);
 827
 828         while (*dir && *dir == *cwd) {
 829                 dir++;
 830                 cwd++;
 831         }
 832         if (*dir)
 833                 return NULL;
 834         if (*cwd == '/')
 835                 return cwd + 1;
 836         return cwd;
 837 }
 838
 839 int is_inside_dir(const char *dir)
 840 {
 841         char buffer[PATH_MAX];
 842         return get_relative_cwd(buffer, sizeof(buffer), dir) != NULL;
 843 }
 844
 845 int is_empty_dir(const char *path)
 846 {
 847         DIR *dir = opendir(path);
 848         struct dirent *e;
 849         int ret = 1;
 850
 851         if (!dir)
 852                 return 0;
 853
 854         while ((e = readdir(dir)) != NULL)
 855                 if (!is_dot_or_dotdot(e->d_name)) {
 856                         ret = 0;
 857                         break;
 858                 }
 859
 860         closedir(dir);
 861         return ret;
 862 }
 863
 864 int remove_dir_recursively(struct strbuf *path, int flag)
 865 {
 866         DIR *dir;
 867         struct dirent *e;
 868         int ret = 0, original_len = path->len, len;
 869         int only_empty = (flag & REMOVE_DIR_EMPTY_ONLY);
 870         unsigned char submodule_head[20];
 871
 872         if ((flag & REMOVE_DIR_KEEP_NESTED_GIT) &&
 873             !resolve_gitlink_ref(path->buf, "HEAD", submodule_head))
 874                 /* Do not descend and nuke a nested git work tree. */
 875                 return 0;
 876
 877         dir = opendir(path->buf);
 878         if (!dir)
 879                 return -1;
 880         if (path->buf[original_len - 1] != '/')
 881                 strbuf_addch(path, '/');
 882
 883         len = path->len;
 884         while ((e = readdir(dir)) != NULL) {
 885                 struct stat st;
 886                 if (is_dot_or_dotdot(e->d_name))
 887                         continue;
 888
 889                 strbuf_setlen(path, len);
 890                 strbuf_addstr(path, e->d_name);
 891                 if (lstat(path->buf, &st))
 892                         ; /* fall thru */
 893                 else if (S_ISDIR(st.st_mode)) {
 894                         if (!remove_dir_recursively(path, only_empty))
 895                                 continue; /* happy */
 896                 } else if (!only_empty && !unlink(path->buf))
 897                         continue; /* happy, too */
 898
 899                 /* path too long, stat fails, or non-directory still exists */
 900                 ret = -1;
 901                 break;
 902         }
 903         closedir(dir);
 904
 905         strbuf_setlen(path, original_len);
 906         if (!ret)
 907                 ret = rmdir(path->buf);
 908         return ret;
 909 }
 910
 911 void setup_standard_excludes(struct dir_struct *dir)
 912 {
 913         const char *path;
 914
 915         dir->exclude_per_dir = ".gitignore";
 916         path = git_path("info/exclude");
 917         if (!access(path, R_OK))
 918                 add_excludes_from_file(dir, path);
 919         if (excludes_file && !access(excludes_file, R_OK))
 920                 add_excludes_from_file(dir, excludes_file);
 921 }
 922
 923 int remove_path(const char *name)
 924 {
 925         char *slash;
 926
 927         if (unlink(name) && errno != ENOENT)
 928                 return -1;
 929
 930         slash = strrchr(name, '/');
 931         if (slash) {
 932                 char *dirs = xstrdup(name);
 933                 slash = dirs + (slash - name);
 934                 do {
 935                         *slash = '\0';
 936                 } while (rmdir(dirs) && (slash = strrchr(dirs, '/')));
 937                 free(dirs);
 938         }
 939         return 0;
 940 }
 941