diff options
Diffstat (limited to 'source4/lib/replace/repdir_getdents.c')
| -rw-r--r-- | source4/lib/replace/repdir_getdents.c | 166 |
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 |