41bdb6e20c
2001-07-06 Paul Eggert <eggert@twinsun.com> * manual/argp.texi: Remove ignored LGPL copyright notice; it's not appropriate for documentation anyway. * manual/libc-texinfo.sh: "Library General Public License" -> "Lesser General Public License". 2001-07-06 Andreas Jaeger <aj@suse.de> * All files under GPL/LGPL version 2: Place under LGPL version 2.1.
86 lines
2.1 KiB
C
86 lines
2.1 KiB
C
/* shm_open -- open a POSIX shared memory object. Generic POSIX file version.
|
|
Copyright (C) 2001 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, write to the Free
|
|
Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
|
|
02111-1307 USA. */
|
|
|
|
#include <unistd.h>
|
|
|
|
#if ! _POSIX_MAPPED_FILES
|
|
#include <sysdeps/generic/shm_open.c>
|
|
|
|
#else
|
|
|
|
#include <errno.h>
|
|
#include <sys/mman.h>
|
|
#include <fcntl.h>
|
|
#include <string.h>
|
|
#include <stdlib.h>
|
|
#include <paths.h>
|
|
|
|
#define SHMDIR (_PATH_VARRUN "shm/")
|
|
|
|
/* Open shared memory object. */
|
|
int
|
|
shm_open (const char *name, int oflag, mode_t mode)
|
|
{
|
|
size_t namelen;
|
|
char *fname;
|
|
int fd;
|
|
|
|
/* Construct the filename. */
|
|
while (name[0] == '/')
|
|
++name;
|
|
|
|
if (name[0] == '\0')
|
|
{
|
|
/* The name "/" is not supported. */
|
|
__set_errno (EINVAL);
|
|
return -1;
|
|
}
|
|
|
|
namelen = strlen (name);
|
|
fname = (char *) __alloca (sizeof SHMDIR - 1 + namelen + 1);
|
|
__mempcpy (__mempcpy (fname, SHMDIR, sizeof SHMDIR - 1),
|
|
name, namelen + 1);
|
|
|
|
fd = open (name, oflag, mode);
|
|
if (fd != -1)
|
|
{
|
|
/* We got a descriptor. Now set the FD_CLOEXEC bit. */
|
|
int flags = fcntl (fd, F_GETFD, 0);
|
|
|
|
if (__builtin_expect (flags, 0) != -1)
|
|
{
|
|
flags |= FD_CLOEXEC;
|
|
flags = fcntl (fd, F_SETFD, flags);
|
|
}
|
|
|
|
if (flags == -1)
|
|
{
|
|
/* Something went wrong. We cannot return the descriptor. */
|
|
int save_errno = errno;
|
|
close (fd);
|
|
fd = -1;
|
|
__set_errno (save_errno);
|
|
}
|
|
}
|
|
|
|
return fd;
|
|
}
|
|
|
|
#endif
|