glibc/sysdeps/unix/opendir.c

94 lines
2.3 KiB
C

/* Copyright (C) 1991, 92, 93, 94, 95, 96, 98 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 Library General Public License as
published by the Free Software Foundation; either version 2 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
Library General Public License for more details.
You should have received a copy of the GNU Library General Public
License along with the GNU C Library; see the file COPYING.LIB. If not,
write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
Boston, MA 02111-1307, USA. */
#include <errno.h>
#include <limits.h>
#include <stddef.h>
#include <stdlib.h>
#include <dirent.h>
#include <fcntl.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <unistd.h>
#include <stdio.h>
#include <dirstream.h>
/* Open a directory stream on NAME. */
DIR *
__opendir (const char *name)
{
DIR *dirp;
struct stat statbuf;
int fd;
size_t allocation;
int save_errno;
if (name[0] == '\0')
{
/* POSIX.1-1990 says an empty name gets ENOENT;
but `open' might like it fine. */
__set_errno (ENOENT);
return NULL;
}
fd = __open (name, O_RDONLY|O_NDELAY);
if (fd < 0)
return NULL;
if (__fcntl (fd, F_SETFD, FD_CLOEXEC) < 0)
goto lose;
if (fstat (fd, &statbuf) < 0)
goto lose;
if (! S_ISDIR (statbuf.st_mode))
{
save_errno = ENOTDIR;
goto lose2;
}
#ifdef _STATBUF_ST_BLKSIZE
if (statbuf.st_blksize < sizeof (struct dirent))
allocation = sizeof (struct dirent);
else
allocation = statbuf.st_blksize;
#else
allocation = (BUFSIZ < sizeof (struct dirent)
? sizeof (struct dirent) : BUFSIZ);
#endif
dirp = (DIR *) calloc (1, sizeof (DIR) + allocation); /* Zero-fill. */
if (dirp == NULL)
lose:
{
save_errno = errno;
lose2:
(void) __close (fd);
__set_errno (save_errno);
return NULL;
}
dirp->data = (char *) (dirp + 1);
dirp->allocation = allocation;
dirp->fd = fd;
__libc_lock_init (dirp->lock);
return dirp;
}
weak_alias (__opendir, opendir)