dir.con commit Documentation/git-checkout: Update summary to reflect current abilities (76ce946)
   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
  12struct path_simplify {
  13        int len;
  14        const char *path;
  15};
  16
  17static int read_directory_recursive(struct dir_struct *dir,
  18        const char *path, const char *base, int baselen,
  19        int check_only, const struct path_simplify *simplify);
  20static int get_dtype(struct dirent *de, const char *path);
  21
  22int common_prefix(const char **pathspec)
  23{
  24        const char *path, *slash, *next;
  25        int prefix;
  26
  27        if (!pathspec)
  28                return 0;
  29
  30        path = *pathspec;
  31        slash = strrchr(path, '/');
  32        if (!slash)
  33                return 0;
  34
  35        prefix = slash - path + 1;
  36        while ((next = *++pathspec) != NULL) {
  37                int len = strlen(next);
  38                if (len >= prefix && !memcmp(path, next, prefix))
  39                        continue;
  40                len = prefix - 1;
  41                for (;;) {
  42                        if (!len)
  43                                return 0;
  44                        if (next[--len] != '/')
  45                                continue;
  46                        if (memcmp(path, next, len+1))
  47                                continue;
  48                        prefix = len + 1;
  49                        break;
  50                }
  51        }
  52        return prefix;
  53}
  54
  55/*
  56 * Does 'match' matches the given name?
  57 * A match is found if
  58 *
  59 * (1) the 'match' string is leading directory of 'name', or
  60 * (2) the 'match' string is a wildcard and matches 'name', or
  61 * (3) the 'match' string is exactly the same as 'name'.
  62 *
  63 * and the return value tells which case it was.
  64 *
  65 * It returns 0 when there is no match.
  66 */
  67static int match_one(const char *match, const char *name, int namelen)
  68{
  69        int matchlen;
  70
  71        /* If the match was just the prefix, we matched */
  72        matchlen = strlen(match);
  73        if (!matchlen)
  74                return MATCHED_RECURSIVELY;
  75
  76        /*
  77         * If we don't match the matchstring exactly,
  78         * we need to match by fnmatch
  79         */
  80        if (strncmp(match, name, matchlen))
  81                return !fnmatch(match, name, 0) ? MATCHED_FNMATCH : 0;
  82
  83        if (!name[matchlen])
  84                return MATCHED_EXACTLY;
  85        if (match[matchlen-1] == '/' || name[matchlen] == '/')
  86                return MATCHED_RECURSIVELY;
  87        return 0;
  88}
  89
  90/*
  91 * Given a name and a list of pathspecs, see if the name matches
  92 * any of the pathspecs.  The caller is also interested in seeing
  93 * all pathspec matches some names it calls this function with
  94 * (otherwise the user could have mistyped the unmatched pathspec),
  95 * and a mark is left in seen[] array for pathspec element that
  96 * actually matched anything.
  97 */
  98int match_pathspec(const char **pathspec, const char *name, int namelen, int prefix, char *seen)
  99{
 100        int retval;
 101        const char *match;
 102
 103        name += prefix;
 104        namelen -= prefix;
 105
 106        for (retval = 0; (match = *pathspec++) != NULL; seen++) {
 107                int how;
 108                if (retval && *seen == MATCHED_EXACTLY)
 109                        continue;
 110                match += prefix;
 111                how = match_one(match, name, namelen);
 112                if (how) {
 113                        if (retval < how)
 114                                retval = how;
 115                        if (*seen < how)
 116                                *seen = how;
 117                }
 118        }
 119        return retval;
 120}
 121
 122static int no_wildcard(const char *string)
 123{
 124        return string[strcspn(string, "*?[{")] == '\0';
 125}
 126
 127void add_exclude(const char *string, const char *base,
 128                 int baselen, struct exclude_list *which)
 129{
 130        struct exclude *x;
 131        size_t len;
 132        int to_exclude = 1;
 133        int flags = 0;
 134
 135        if (*string == '!') {
 136                to_exclude = 0;
 137                string++;
 138        }
 139        len = strlen(string);
 140        if (len && string[len - 1] == '/') {
 141                char *s;
 142                x = xmalloc(sizeof(*x) + len);
 143                s = (char*)(x+1);
 144                memcpy(s, string, len - 1);
 145                s[len - 1] = '\0';
 146                string = s;
 147                x->pattern = s;
 148                flags = EXC_FLAG_MUSTBEDIR;
 149        } else {
 150                x = xmalloc(sizeof(*x));
 151                x->pattern = string;
 152        }
 153        x->to_exclude = to_exclude;
 154        x->patternlen = strlen(string);
 155        x->base = base;
 156        x->baselen = baselen;
 157        x->flags = flags;
 158        if (!strchr(string, '/'))
 159                x->flags |= EXC_FLAG_NODIR;
 160        if (no_wildcard(string))
 161                x->flags |= EXC_FLAG_NOWILDCARD;
 162        if (*string == '*' && no_wildcard(string+1))
 163                x->flags |= EXC_FLAG_ENDSWITH;
 164        ALLOC_GROW(which->excludes, which->nr + 1, which->alloc);
 165        which->excludes[which->nr++] = x;
 166}
 167
 168static int add_excludes_from_file_1(const char *fname,
 169                                    const char *base,
 170                                    int baselen,
 171                                    char **buf_p,
 172                                    struct exclude_list *which)
 173{
 174        struct stat st;
 175        int fd, i;
 176        size_t size;
 177        char *buf, *entry;
 178
 179        fd = open(fname, O_RDONLY);
 180        if (fd < 0 || fstat(fd, &st) < 0)
 181                goto err;
 182        size = xsize_t(st.st_size);
 183        if (size == 0) {
 184                close(fd);
 185                return 0;
 186        }
 187        buf = xmalloc(size+1);
 188        if (read_in_full(fd, buf, size) != size)
 189        {
 190                free(buf);
 191                goto err;
 192        }
 193        close(fd);
 194
 195        if (buf_p)
 196                *buf_p = buf;
 197        buf[size++] = '\n';
 198        entry = buf;
 199        for (i = 0; i < size; i++) {
 200                if (buf[i] == '\n') {
 201                        if (entry != buf + i && entry[0] != '#') {
 202                                buf[i - (i && buf[i-1] == '\r')] = 0;
 203                                add_exclude(entry, base, baselen, which);
 204                        }
 205                        entry = buf + i + 1;
 206                }
 207        }
 208        return 0;
 209
 210 err:
 211        if (0 <= fd)
 212                close(fd);
 213        return -1;
 214}
 215
 216void add_excludes_from_file(struct dir_struct *dir, const char *fname)
 217{
 218        if (add_excludes_from_file_1(fname, "", 0, NULL,
 219                                     &dir->exclude_list[EXC_FILE]) < 0)
 220                die("cannot use %s as an exclude file", fname);
 221}
 222
 223static void prep_exclude(struct dir_struct *dir, const char *base, int baselen)
 224{
 225        struct exclude_list *el;
 226        struct exclude_stack *stk = NULL;
 227        int current;
 228
 229        if ((!dir->exclude_per_dir) ||
 230            (baselen + strlen(dir->exclude_per_dir) >= PATH_MAX))
 231                return; /* too long a path -- ignore */
 232
 233        /* Pop the ones that are not the prefix of the path being checked. */
 234        el = &dir->exclude_list[EXC_DIRS];
 235        while ((stk = dir->exclude_stack) != NULL) {
 236                if (stk->baselen <= baselen &&
 237                    !strncmp(dir->basebuf, base, stk->baselen))
 238                        break;
 239                dir->exclude_stack = stk->prev;
 240                while (stk->exclude_ix < el->nr)
 241                        free(el->excludes[--el->nr]);
 242                free(stk->filebuf);
 243                free(stk);
 244        }
 245
 246        /* Read from the parent directories and push them down. */
 247        current = stk ? stk->baselen : -1;
 248        while (current < baselen) {
 249                struct exclude_stack *stk = xcalloc(1, sizeof(*stk));
 250                const char *cp;
 251
 252                if (current < 0) {
 253                        cp = base;
 254                        current = 0;
 255                }
 256                else {
 257                        cp = strchr(base + current + 1, '/');
 258                        if (!cp)
 259                                die("oops in prep_exclude");
 260                        cp++;
 261                }
 262                stk->prev = dir->exclude_stack;
 263                stk->baselen = cp - base;
 264                stk->exclude_ix = el->nr;
 265                memcpy(dir->basebuf + current, base + current,
 266                       stk->baselen - current);
 267                strcpy(dir->basebuf + stk->baselen, dir->exclude_per_dir);
 268                add_excludes_from_file_1(dir->basebuf,
 269                                         dir->basebuf, stk->baselen,
 270                                         &stk->filebuf, el);
 271                dir->exclude_stack = stk;
 272                current = stk->baselen;
 273        }
 274        dir->basebuf[baselen] = '\0';
 275}
 276
 277/* Scan the list and let the last match determines the fate.
 278 * Return 1 for exclude, 0 for include and -1 for undecided.
 279 */
 280static int excluded_1(const char *pathname,
 281                      int pathlen, const char *basename, int *dtype,
 282                      struct exclude_list *el)
 283{
 284        int i;
 285
 286        if (el->nr) {
 287                for (i = el->nr - 1; 0 <= i; i--) {
 288                        struct exclude *x = el->excludes[i];
 289                        const char *exclude = x->pattern;
 290                        int to_exclude = x->to_exclude;
 291
 292                        if (x->flags & EXC_FLAG_MUSTBEDIR) {
 293                                if (*dtype == DT_UNKNOWN)
 294                                        *dtype = get_dtype(NULL, pathname);
 295                                if (*dtype != DT_DIR)
 296                                        continue;
 297                        }
 298
 299                        if (x->flags & EXC_FLAG_NODIR) {
 300                                /* match basename */
 301                                if (x->flags & EXC_FLAG_NOWILDCARD) {
 302                                        if (!strcmp(exclude, basename))
 303                                                return to_exclude;
 304                                } else if (x->flags & EXC_FLAG_ENDSWITH) {
 305                                        if (x->patternlen - 1 <= pathlen &&
 306                                            !strcmp(exclude + 1, pathname + pathlen - x->patternlen + 1))
 307                                                return to_exclude;
 308                                } else {
 309                                        if (fnmatch(exclude, basename, 0) == 0)
 310                                                return to_exclude;
 311                                }
 312                        }
 313                        else {
 314                                /* match with FNM_PATHNAME:
 315                                 * exclude has base (baselen long) implicitly
 316                                 * in front of it.
 317                                 */
 318                                int baselen = x->baselen;
 319                                if (*exclude == '/')
 320                                        exclude++;
 321
 322                                if (pathlen < baselen ||
 323                                    (baselen && pathname[baselen-1] != '/') ||
 324                                    strncmp(pathname, x->base, baselen))
 325                                    continue;
 326
 327                                if (x->flags & EXC_FLAG_NOWILDCARD) {
 328                                        if (!strcmp(exclude, pathname + baselen))
 329                                                return to_exclude;
 330                                } else {
 331                                        if (fnmatch(exclude, pathname+baselen,
 332                                                    FNM_PATHNAME) == 0)
 333                                            return to_exclude;
 334                                }
 335                        }
 336                }
 337        }
 338        return -1; /* undecided */
 339}
 340
 341int excluded(struct dir_struct *dir, const char *pathname, int *dtype_p)
 342{
 343        int pathlen = strlen(pathname);
 344        int st;
 345        const char *basename = strrchr(pathname, '/');
 346        basename = (basename) ? basename+1 : pathname;
 347
 348        prep_exclude(dir, pathname, basename-pathname);
 349        for (st = EXC_CMDL; st <= EXC_FILE; st++) {
 350                switch (excluded_1(pathname, pathlen, basename,
 351                                   dtype_p, &dir->exclude_list[st])) {
 352                case 0:
 353                        return 0;
 354                case 1:
 355                        return 1;
 356                }
 357        }
 358        return 0;
 359}
 360
 361static struct dir_entry *dir_entry_new(const char *pathname, int len)
 362{
 363        struct dir_entry *ent;
 364
 365        ent = xmalloc(sizeof(*ent) + len + 1);
 366        ent->len = len;
 367        memcpy(ent->name, pathname, len);
 368        ent->name[len] = 0;
 369        return ent;
 370}
 371
 372struct dir_entry *dir_add_name(struct dir_struct *dir, const char *pathname, int len)
 373{
 374        if (cache_name_exists(pathname, len))
 375                return NULL;
 376
 377        ALLOC_GROW(dir->entries, dir->nr+1, dir->alloc);
 378        return dir->entries[dir->nr++] = dir_entry_new(pathname, len);
 379}
 380
 381struct dir_entry *dir_add_ignored(struct dir_struct *dir, const char *pathname, int len)
 382{
 383        if (cache_name_pos(pathname, len) >= 0)
 384                return NULL;
 385
 386        ALLOC_GROW(dir->ignored, dir->ignored_nr+1, dir->ignored_alloc);
 387        return dir->ignored[dir->ignored_nr++] = dir_entry_new(pathname, len);
 388}
 389
 390enum exist_status {
 391        index_nonexistent = 0,
 392        index_directory,
 393        index_gitdir,
 394};
 395
 396/*
 397 * The index sorts alphabetically by entry name, which
 398 * means that a gitlink sorts as '\0' at the end, while
 399 * a directory (which is defined not as an entry, but as
 400 * the files it contains) will sort with the '/' at the
 401 * end.
 402 */
 403static enum exist_status directory_exists_in_index(const char *dirname, int len)
 404{
 405        int pos = cache_name_pos(dirname, len);
 406        if (pos < 0)
 407                pos = -pos-1;
 408        while (pos < active_nr) {
 409                struct cache_entry *ce = active_cache[pos++];
 410                unsigned char endchar;
 411
 412                if (strncmp(ce->name, dirname, len))
 413                        break;
 414                endchar = ce->name[len];
 415                if (endchar > '/')
 416                        break;
 417                if (endchar == '/')
 418                        return index_directory;
 419                if (!endchar && S_ISGITLINK(ce->ce_mode))
 420                        return index_gitdir;
 421        }
 422        return index_nonexistent;
 423}
 424
 425/*
 426 * When we find a directory when traversing the filesystem, we
 427 * have three distinct cases:
 428 *
 429 *  - ignore it
 430 *  - see it as a directory
 431 *  - recurse into it
 432 *
 433 * and which one we choose depends on a combination of existing
 434 * git index contents and the flags passed into the directory
 435 * traversal routine.
 436 *
 437 * Case 1: If we *already* have entries in the index under that
 438 * directory name, we always recurse into the directory to see
 439 * all the files.
 440 *
 441 * Case 2: If we *already* have that directory name as a gitlink,
 442 * we always continue to see it as a gitlink, regardless of whether
 443 * there is an actual git directory there or not (it might not
 444 * be checked out as a subproject!)
 445 *
 446 * Case 3: if we didn't have it in the index previously, we
 447 * have a few sub-cases:
 448 *
 449 *  (a) if "show_other_directories" is true, we show it as
 450 *      just a directory, unless "hide_empty_directories" is
 451 *      also true and the directory is empty, in which case
 452 *      we just ignore it entirely.
 453 *  (b) if it looks like a git directory, and we don't have
 454 *      'no_gitlinks' set we treat it as a gitlink, and show it
 455 *      as a directory.
 456 *  (c) otherwise, we recurse into it.
 457 */
 458enum directory_treatment {
 459        show_directory,
 460        ignore_directory,
 461        recurse_into_directory,
 462};
 463
 464static enum directory_treatment treat_directory(struct dir_struct *dir,
 465        const char *dirname, int len,
 466        const struct path_simplify *simplify)
 467{
 468        /* The "len-1" is to strip the final '/' */
 469        switch (directory_exists_in_index(dirname, len-1)) {
 470        case index_directory:
 471                return recurse_into_directory;
 472
 473        case index_gitdir:
 474                if (dir->show_other_directories)
 475                        return ignore_directory;
 476                return show_directory;
 477
 478        case index_nonexistent:
 479                if (dir->show_other_directories)
 480                        break;
 481                if (!dir->no_gitlinks) {
 482                        unsigned char sha1[20];
 483                        if (resolve_gitlink_ref(dirname, "HEAD", sha1) == 0)
 484                                return show_directory;
 485                }
 486                return recurse_into_directory;
 487        }
 488
 489        /* This is the "show_other_directories" case */
 490        if (!dir->hide_empty_directories)
 491                return show_directory;
 492        if (!read_directory_recursive(dir, dirname, dirname, len, 1, simplify))
 493                return ignore_directory;
 494        return show_directory;
 495}
 496
 497/*
 498 * This is an inexact early pruning of any recursive directory
 499 * reading - if the path cannot possibly be in the pathspec,
 500 * return true, and we'll skip it early.
 501 */
 502static int simplify_away(const char *path, int pathlen, const struct path_simplify *simplify)
 503{
 504        if (simplify) {
 505                for (;;) {
 506                        const char *match = simplify->path;
 507                        int len = simplify->len;
 508
 509                        if (!match)
 510                                break;
 511                        if (len > pathlen)
 512                                len = pathlen;
 513                        if (!memcmp(path, match, len))
 514                                return 0;
 515                        simplify++;
 516                }
 517                return 1;
 518        }
 519        return 0;
 520}
 521
 522static int in_pathspec(const char *path, int len, const struct path_simplify *simplify)
 523{
 524        if (simplify) {
 525                for (; simplify->path; simplify++) {
 526                        if (len == simplify->len
 527                            && !memcmp(path, simplify->path, len))
 528                                return 1;
 529                }
 530        }
 531        return 0;
 532}
 533
 534static int get_dtype(struct dirent *de, const char *path)
 535{
 536        int dtype = de ? DTYPE(de) : DT_UNKNOWN;
 537        struct stat st;
 538
 539        if (dtype != DT_UNKNOWN)
 540                return dtype;
 541        if (lstat(path, &st))
 542                return dtype;
 543        if (S_ISREG(st.st_mode))
 544                return DT_REG;
 545        if (S_ISDIR(st.st_mode))
 546                return DT_DIR;
 547        if (S_ISLNK(st.st_mode))
 548                return DT_LNK;
 549        return dtype;
 550}
 551
 552/*
 553 * Read a directory tree. We currently ignore anything but
 554 * directories, regular files and symlinks. That's because git
 555 * doesn't handle them at all yet. Maybe that will change some
 556 * day.
 557 *
 558 * Also, we ignore the name ".git" (even if it is not a directory).
 559 * That likely will not change.
 560 */
 561static int read_directory_recursive(struct dir_struct *dir, const char *path, const char *base, int baselen, int check_only, const struct path_simplify *simplify)
 562{
 563        DIR *fdir = opendir(path);
 564        int contents = 0;
 565
 566        if (fdir) {
 567                struct dirent *de;
 568                char fullname[PATH_MAX + 1];
 569                memcpy(fullname, base, baselen);
 570
 571                while ((de = readdir(fdir)) != NULL) {
 572                        int len, dtype;
 573                        int exclude;
 574
 575                        if ((de->d_name[0] == '.') &&
 576                            (de->d_name[1] == 0 ||
 577                             !strcmp(de->d_name + 1, ".") ||
 578                             !strcmp(de->d_name + 1, "git")))
 579                                continue;
 580                        len = strlen(de->d_name);
 581                        /* Ignore overly long pathnames! */
 582                        if (len + baselen + 8 > sizeof(fullname))
 583                                continue;
 584                        memcpy(fullname + baselen, de->d_name, len+1);
 585                        if (simplify_away(fullname, baselen + len, simplify))
 586                                continue;
 587
 588                        dtype = DTYPE(de);
 589                        exclude = excluded(dir, fullname, &dtype);
 590                        if (exclude && dir->collect_ignored
 591                            && in_pathspec(fullname, baselen + len, simplify))
 592                                dir_add_ignored(dir, fullname, baselen + len);
 593
 594                        /*
 595                         * Excluded? If we don't explicitly want to show
 596                         * ignored files, ignore it
 597                         */
 598                        if (exclude && !dir->show_ignored)
 599                                continue;
 600
 601                        if (dtype == DT_UNKNOWN)
 602                                dtype = get_dtype(de, fullname);
 603
 604                        /*
 605                         * Do we want to see just the ignored files?
 606                         * We still need to recurse into directories,
 607                         * even if we don't ignore them, since the
 608                         * directory may contain files that we do..
 609                         */
 610                        if (!exclude && dir->show_ignored) {
 611                                if (dtype != DT_DIR)
 612                                        continue;
 613                        }
 614
 615                        switch (dtype) {
 616                        default:
 617                                continue;
 618                        case DT_DIR:
 619                                memcpy(fullname + baselen + len, "/", 2);
 620                                len++;
 621                                switch (treat_directory(dir, fullname, baselen + len, simplify)) {
 622                                case show_directory:
 623                                        if (exclude != dir->show_ignored)
 624                                                continue;
 625                                        break;
 626                                case recurse_into_directory:
 627                                        contents += read_directory_recursive(dir,
 628                                                fullname, fullname, baselen + len, 0, simplify);
 629                                        continue;
 630                                case ignore_directory:
 631                                        continue;
 632                                }
 633                                break;
 634                        case DT_REG:
 635                        case DT_LNK:
 636                                break;
 637                        }
 638                        contents++;
 639                        if (check_only)
 640                                goto exit_early;
 641                        else
 642                                dir_add_name(dir, fullname, baselen + len);
 643                }
 644exit_early:
 645                closedir(fdir);
 646        }
 647
 648        return contents;
 649}
 650
 651static int cmp_name(const void *p1, const void *p2)
 652{
 653        const struct dir_entry *e1 = *(const struct dir_entry **)p1;
 654        const struct dir_entry *e2 = *(const struct dir_entry **)p2;
 655
 656        return cache_name_compare(e1->name, e1->len,
 657                                  e2->name, e2->len);
 658}
 659
 660/*
 661 * Return the length of the "simple" part of a path match limiter.
 662 */
 663static int simple_length(const char *match)
 664{
 665        const char special[256] = {
 666                [0] = 1, ['?'] = 1,
 667                ['\\'] = 1, ['*'] = 1,
 668                ['['] = 1
 669        };
 670        int len = -1;
 671
 672        for (;;) {
 673                unsigned char c = *match++;
 674                len++;
 675                if (special[c])
 676                        return len;
 677        }
 678}
 679
 680static struct path_simplify *create_simplify(const char **pathspec)
 681{
 682        int nr, alloc = 0;
 683        struct path_simplify *simplify = NULL;
 684
 685        if (!pathspec)
 686                return NULL;
 687
 688        for (nr = 0 ; ; nr++) {
 689                const char *match;
 690                if (nr >= alloc) {
 691                        alloc = alloc_nr(alloc);
 692                        simplify = xrealloc(simplify, alloc * sizeof(*simplify));
 693                }
 694                match = *pathspec++;
 695                if (!match)
 696                        break;
 697                simplify[nr].path = match;
 698                simplify[nr].len = simple_length(match);
 699        }
 700        simplify[nr].path = NULL;
 701        simplify[nr].len = 0;
 702        return simplify;
 703}
 704
 705static void free_simplify(struct path_simplify *simplify)
 706{
 707        free(simplify);
 708}
 709
 710int read_directory(struct dir_struct *dir, const char *path, const char *base, int baselen, const char **pathspec)
 711{
 712        struct path_simplify *simplify = create_simplify(pathspec);
 713
 714        read_directory_recursive(dir, path, base, baselen, 0, simplify);
 715        free_simplify(simplify);
 716        qsort(dir->entries, dir->nr, sizeof(struct dir_entry *), cmp_name);
 717        qsort(dir->ignored, dir->ignored_nr, sizeof(struct dir_entry *), cmp_name);
 718        return dir->nr;
 719}
 720
 721int file_exists(const char *f)
 722{
 723        struct stat sb;
 724        return lstat(f, &sb) == 0;
 725}
 726
 727/*
 728 * get_relative_cwd() gets the prefix of the current working directory
 729 * relative to 'dir'.  If we are not inside 'dir', it returns NULL.
 730 *
 731 * As a convenience, it also returns NULL if 'dir' is already NULL.  The
 732 * reason for this behaviour is that it is natural for functions returning
 733 * directory names to return NULL to say "this directory does not exist"
 734 * or "this directory is invalid".  These cases are usually handled the
 735 * same as if the cwd is not inside 'dir' at all, so get_relative_cwd()
 736 * returns NULL for both of them.
 737 *
 738 * Most notably, get_relative_cwd(buffer, size, get_git_work_tree())
 739 * unifies the handling of "outside work tree" with "no work tree at all".
 740 */
 741char *get_relative_cwd(char *buffer, int size, const char *dir)
 742{
 743        char *cwd = buffer;
 744
 745        if (!dir)
 746                return NULL;
 747        if (!getcwd(buffer, size))
 748                die("can't find the current directory: %s", strerror(errno));
 749
 750        if (!is_absolute_path(dir))
 751                dir = make_absolute_path(dir);
 752
 753        while (*dir && *dir == *cwd) {
 754                dir++;
 755                cwd++;
 756        }
 757        if (*dir)
 758                return NULL;
 759        if (*cwd == '/')
 760                return cwd + 1;
 761        return cwd;
 762}
 763
 764int is_inside_dir(const char *dir)
 765{
 766        char buffer[PATH_MAX];
 767        return get_relative_cwd(buffer, sizeof(buffer), dir) != NULL;
 768}
 769
 770int remove_dir_recursively(struct strbuf *path, int only_empty)
 771{
 772        DIR *dir = opendir(path->buf);
 773        struct dirent *e;
 774        int ret = 0, original_len = path->len, len;
 775
 776        if (!dir)
 777                return -1;
 778        if (path->buf[original_len - 1] != '/')
 779                strbuf_addch(path, '/');
 780
 781        len = path->len;
 782        while ((e = readdir(dir)) != NULL) {
 783                struct stat st;
 784                if ((e->d_name[0] == '.') &&
 785                    ((e->d_name[1] == 0) ||
 786                     ((e->d_name[1] == '.') && e->d_name[2] == 0)))
 787                        continue; /* "." and ".." */
 788
 789                strbuf_setlen(path, len);
 790                strbuf_addstr(path, e->d_name);
 791                if (lstat(path->buf, &st))
 792                        ; /* fall thru */
 793                else if (S_ISDIR(st.st_mode)) {
 794                        if (!remove_dir_recursively(path, only_empty))
 795                                continue; /* happy */
 796                } else if (!only_empty && !unlink(path->buf))
 797                        continue; /* happy, too */
 798
 799                /* path too long, stat fails, or non-directory still exists */
 800                ret = -1;
 801                break;
 802        }
 803        closedir(dir);
 804
 805        strbuf_setlen(path, original_len);
 806        if (!ret)
 807                ret = rmdir(path->buf);
 808        return ret;
 809}
 810
 811void setup_standard_excludes(struct dir_struct *dir)
 812{
 813        const char *path;
 814
 815        dir->exclude_per_dir = ".gitignore";
 816        path = git_path("info/exclude");
 817        if (!access(path, R_OK))
 818                add_excludes_from_file(dir, path);
 819        if (excludes_file && !access(excludes_file, R_OK))
 820                add_excludes_from_file(dir, excludes_file);
 821}