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Diffstat (limited to 'source4/lib/replace/repdir_getdents.c')
-rw-r--r--source4/lib/replace/repdir_getdents.c166
1 files changed, 0 insertions, 166 deletions
diff --git a/source4/lib/replace/repdir_getdents.c b/source4/lib/replace/repdir_getdents.c
deleted file mode 100644
index afc634a796..0000000000
--- a/source4/lib/replace/repdir_getdents.c
+++ /dev/null
@@ -1,166 +0,0 @@
-/*
- Unix SMB/CIFS implementation.
-
- Copyright (C) Andrew Tridgell 2005
-
- ** NOTE! The following LGPL license applies to the replace
- ** library. This does NOT imply that all of Samba is released
- ** under the LGPL
-
- This library is free software; you can redistribute it and/or
- modify it under the terms of the GNU Lesser General Public
- License as published by the Free Software Foundation; either
- version 3 of the License, or (at your option) any later version.
-
- This library is distributed in the hope that it will be useful,
- but WITHOUT ANY WARRANTY; without even the implied warranty of
- MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
- Lesser General Public License for more details.
-
- You should have received a copy of the GNU Lesser General Public
- License along with this library; if not, see <http://www.gnu.org/licenses/>.
-*/
-/*
- a replacement for opendir/readdir/telldir/seekdir/closedir for BSD systems
-
- This is needed because the existing directory handling in FreeBSD
- and OpenBSD (and possibly NetBSD) doesn't correctly handle unlink()
- on files in a directory where telldir() has been used. On a block
- boundary it will occasionally miss a file when seekdir() is used to
- return to a position previously recorded with telldir().
-
- This also fixes a severe performance and memory usage problem with
- telldir() on BSD systems. Each call to telldir() in BSD adds an
- entry to a linked list, and those entries are cleaned up on
- closedir(). This means with a large directory closedir() can take an
- arbitrary amount of time, causing network timeouts as millions of
- telldir() entries are freed
-
- Note! This replacement code is not portable. It relies on getdents()
- always leaving the file descriptor at a seek offset that is a
- multiple of DIR_BUF_SIZE. If the code detects that this doesn't
- happen then it will abort(). It also does not handle directories
- with offsets larger than can be stored in a long,
-
- This code is available under other free software licenses as
- well. Contact the author.
-*/
-
-#include <stdlib.h>
-#include <sys/stat.h>
-#include <unistd.h>
-#include <sys/types.h>
-#include <errno.h>
-#include <fcntl.h>
-#include <dirent.h>
-
-#define DIR_BUF_BITS 9
-#define DIR_BUF_SIZE (1<<DIR_BUF_BITS)
-
-struct dir_buf {
- int fd;
- int nbytes, ofs;
- off_t seekpos;
- char buf[DIR_BUF_SIZE];
-};
-
-DIR *opendir(const char *dname)
-{
- struct dir_buf *d;
- struct stat sb;
- d = malloc(sizeof(*d));
- if (d == NULL) {
- errno = ENOMEM;
- return NULL;
- }
- d->fd = open(dname, O_RDONLY);
- if (d->fd == -1) {
- free(d);
- return NULL;
- }
- if (fstat(d->fd, &sb) < 0) {
- close(d->fd);
- free(d);
- return NULL;
- }
- if (!S_ISDIR(sb.st_mode)) {
- close(d->fd);
- free(d);
- errno = ENOTDIR;
- return NULL;
- }
- d->ofs = 0;
- d->seekpos = 0;
- d->nbytes = 0;
- return (DIR *)d;
-}
-
-struct dirent *readdir(DIR *dir)
-{
- struct dir_buf *d = (struct dir_buf *)dir;
- struct dirent *de;
-
- if (d->ofs >= d->nbytes) {
- d->seekpos = lseek(d->fd, 0, SEEK_CUR);
- d->nbytes = getdents(d->fd, d->buf, DIR_BUF_SIZE);
- d->ofs = 0;
- }
- if (d->ofs >= d->nbytes) {
- return NULL;
- }
- de = (struct dirent *)&d->buf[d->ofs];
- d->ofs += de->d_reclen;
- return de;
-}
-
-long telldir(DIR *dir)
-{
- struct dir_buf *d = (struct dir_buf *)dir;
- if (d->ofs >= d->nbytes) {
- d->seekpos = lseek(d->fd, 0, SEEK_CUR);
- d->ofs = 0;
- d->nbytes = 0;
- }
- /* this relies on seekpos always being a multiple of
- DIR_BUF_SIZE. Is that always true on BSD systems? */
- if (d->seekpos & (DIR_BUF_SIZE-1)) {
- abort();
- }
- return d->seekpos + d->ofs;
-}
-
-void seekdir(DIR *dir, long ofs)
-{
- struct dir_buf *d = (struct dir_buf *)dir;
- d->seekpos = lseek(d->fd, ofs & ~(DIR_BUF_SIZE-1), SEEK_SET);
- d->nbytes = getdents(d->fd, d->buf, DIR_BUF_SIZE);
- d->ofs = 0;
- while (d->ofs < (ofs & (DIR_BUF_SIZE-1))) {
- if (readdir(dir) == NULL) break;
- }
-}
-
-void rewinddir(DIR *dir)
-{
- seekdir(dir, 0);
-}
-
-int closedir(DIR *dir)
-{
- struct dir_buf *d = (struct dir_buf *)dir;
- int r = close(d->fd);
- if (r != 0) {
- return r;
- }
- free(d);
- return 0;
-}
-
-#ifndef dirfd
-/* darn, this is a macro on some systems. */
-int dirfd(DIR *dir)
-{
- struct dir_buf *d = (struct dir_buf *)dir;
- return d->fd;
-}
-#endif