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Lines 33-40
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#include <sys/cdefs.h> |
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#include <sys/cdefs.h> |
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__FBSDID("$FreeBSD: src/lib/libc/gen/rewinddir.c,v 1.6 2007/01/09 00:27:55 imp Exp $"); |
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__FBSDID("$FreeBSD: src/lib/libc/gen/rewinddir.c,v 1.6 2007/01/09 00:27:55 imp Exp $"); |
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#include "namespace.h" |
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#include <sys/types.h> |
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#include <sys/types.h> |
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#include <sys/param.h> |
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#include <sys/mount.h> |
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#include <errno.h> |
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#include <fcntl.h> |
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#include <unistd.h> |
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#include <dirent.h> |
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#include <dirent.h> |
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#include <stdlib.h> |
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#include <string.h> |
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#include "un-namespace.h" |
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#include "telldir.h" |
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#include "telldir.h" |
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Lines 42-48
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| 42 |
rewinddir(dirp) |
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rewinddir(dirp) |
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DIR *dirp; |
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DIR *dirp; |
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{ |
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{ |
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_seekdir(dirp, dirp->dd_rewind); |
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_seekdir(dirp, dirp->dd_rewind); |
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int incr; |
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int unionstack; |
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/* |
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* Use the system page size if that is a multiple of DIRBLKSIZ. |
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* Hopefully this can be a big win someday by allowing page |
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* trades to user space to be done by _getdirentries(). |
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*/ |
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incr = getpagesize(); |
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if ((incr % DIRBLKSIZ) != 0) |
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incr = DIRBLKSIZ; |
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/* |
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* Determine whether this directory is the top of a union stack. |
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*/ |
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if (dirp->dd_flags & DTF_NODUP) { |
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struct statfs sfb; |
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if (_fstatfs(dirp->dd_fd, &sfb) < 0) |
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goto fail; |
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unionstack = !strcmp(sfb.f_fstypename, "unionfs") |
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|| (sfb.f_flags & MNT_UNION); |
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} else { |
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unionstack = 0; |
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} |
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if (unionstack) { |
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int len = dirp->dd_len; |
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int space = dirp->dd_len; |
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char *buf = dirp->dd_buf; |
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char *ddptr = dirp->dd_buf; |
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char *ddeptr; |
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int n; |
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struct dirent **dpv; |
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if (lseek(dirp->dd_fd, 0, SEEK_SET) == -1) |
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goto fail; |
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dirp->dd_seek = 0; |
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/* |
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* The strategy here is to read all the directory |
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* entries into a buffer, sort the buffer, and |
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* remove duplicate entries by setting the inode |
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* number to zero. |
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*/ |
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do { |
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/* |
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* Always make at least DIRBLKSIZ bytes |
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* available to _getdirentries |
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*/ |
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if (space < DIRBLKSIZ) { |
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space += incr; |
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len += incr; |
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buf = reallocf(buf, len); |
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if (buf == NULL) |
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goto fail; |
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ddptr = buf + (len - space); |
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} |
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n = _getdirentries(dirp->dd_fd, ddptr, space, &dirp->dd_seek); |
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if (n > 0) { |
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ddptr += n; |
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space -= n; |
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} |
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} while (n > 0); |
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ddeptr = ddptr; |
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dirp->dd_flags |= __DTF_READALL; |
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/* |
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* There is now a buffer full of (possibly) duplicate |
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* names. |
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*/ |
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dirp->dd_buf = buf; |
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/* |
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* Go round this loop twice... |
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* |
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* Scan through the buffer, counting entries. |
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* On the second pass, save pointers to each one. |
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* Then sort the pointers and remove duplicate names. |
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*/ |
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for (dpv = 0;;) { |
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n = 0; |
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ddptr = buf; |
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while (ddptr < ddeptr) { |
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struct dirent *dp; |
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dp = (struct dirent *) ddptr; |
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if ((long)dp & 03L) |
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break; |
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if ((dp->d_reclen <= 0) || |
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(dp->d_reclen > (ddeptr + 1 - ddptr))) |
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break; |
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ddptr += dp->d_reclen; |
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if (dp->d_fileno) { |
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if (dpv) |
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dpv[n] = dp; |
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n++; |
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} |
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} |
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if (dpv) { |
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struct dirent *xp; |
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/* |
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* This sort must be stable. |
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*/ |
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mergesort(dpv, n, sizeof(*dpv), alphasort); |
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dpv[n] = NULL; |
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xp = NULL; |
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/* |
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* Scan through the buffer in sort order, |
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* zapping the inode number of any |
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* duplicate names. |
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*/ |
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for (n = 0; dpv[n]; n++) { |
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struct dirent *dp = dpv[n]; |
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if ((xp == NULL) || |
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strcmp(dp->d_name, xp->d_name)) { |
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xp = dp; |
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} else { |
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dp->d_fileno = 0; |
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} |
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if (dp->d_type == DT_WHT && |
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(dirp->dd_flags & DTF_HIDEW)) |
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dp->d_fileno = 0; |
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} |
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free(dpv); |
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break; |
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} else { |
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dpv = malloc((n+1) * sizeof(struct dirent *)); |
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if (dpv == NULL) |
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break; |
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} |
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} |
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dirp->dd_len = len; |
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dirp->dd_loc = 0; |
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dirp->dd_size = ddptr - dirp->dd_buf; |
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} |
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/* |
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* Silently ignore any errors |
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*/ |
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fail: |
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dirp->dd_rewind = telldir(dirp); |
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dirp->dd_rewind = telldir(dirp); |
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} |
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} |