glibc/sysdeps/unix/sysv/linux/readdir.c
Adhemerval Zanella 905ae44c77 linux: Move posix dir implementations to Linux
This generic implementation already expects a getdents API which
is Linux specific.  It also allows simplify it by assuming
_DIRENT_HAVE_D_RECLEN and _DIRENT_HAVE_D_OFF support.

The readdir are also expanded on each required implementation,
futher fixes and improvements will make parametrize the
implementation more complex.

Checked on x86_64-linux-gnu, i686-linux-gnu, and with a build
for all affected ABIs.
2020-10-16 14:19:23 -03:00

87 lines
2.1 KiB
C

/* Read a directory. Linux no-LFS version.
Copyright (C) 2018-2020 Free Software Foundation, Inc.
This file is part of the GNU C Library.
The GNU C 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 2.1 of the License, or (at your option) any later version.
The GNU C 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 the GNU C Library; if not, see
<https://www.gnu.org/licenses/>. */
#include <dirent.h>
#if !_DIRENT_MATCHES_DIRENT64
#include <dirstream.h>
/* Read a directory entry from DIRP. */
struct dirent *
__readdir (DIR *dirp)
{
struct dirent *dp;
int saved_errno = errno;
#if IS_IN (libc)
__libc_lock_lock (dirp->lock);
#endif
do
{
size_t reclen;
if (dirp->offset >= dirp->size)
{
/* We've emptied out our buffer. Refill it. */
size_t maxread = dirp->allocation;
ssize_t bytes;
bytes = __getdents (dirp->fd, dirp->data, maxread);
if (bytes <= 0)
{
/* On some systems getdents fails with ENOENT when the
open directory has been rmdir'd already. POSIX.1
requires that we treat this condition like normal EOF. */
if (bytes < 0 && errno == ENOENT)
bytes = 0;
/* Don't modifiy errno when reaching EOF. */
if (bytes == 0)
__set_errno (saved_errno);
dp = NULL;
break;
}
dirp->size = (size_t) bytes;
/* Reset the offset into the buffer. */
dirp->offset = 0;
}
dp = (struct dirent *) &dirp->data[dirp->offset];
reclen = dp->d_reclen;
dirp->offset += reclen;
dirp->filepos = dp->d_off;
/* Skip deleted files. */
} while (dp->d_ino == 0);
#if IS_IN (libc)
__libc_lock_unlock (dirp->lock);
#endif
return dp;
}
weak_alias (__readdir, readdir)
#endif