/* SysV shmat for Hurd.
Copyright (C) 2005-2015 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
. */
#include
#include
#include
#include
#include
#include
#include
#include
#include
#include
#include "sysvshm.h"
/* Attach the shared memory segment associated with SHMID to the data
segment of the calling process. SHMADDR and SHMFLG determine how
and where the segment is attached. */
void *
__shmat (int shmid, const void *shmaddr, int shmflg)
{
error_t err;
char filename[sizeof (SHM_DIR) - 1 + SHM_NAMEMAX];
int fd;
void *addr;
struct stat statbuf;
int res;
sprintf (filename, SHM_DIR SHM_NAMEPRI, shmid);
fd = __open (filename, (shmflg & SHM_RDONLY) ? O_RDONLY : O_RDWR);
if (fd < 0)
{
if (errno == ENOENT)
errno = EINVAL;
return (void *) -1;
}
res = __fstat (fd, &statbuf);
if (res < 0)
{
err = errno;
__close (fd);
errno = err;
return (void *) -1;
}
addr = __mmap ((void *) shmaddr, statbuf.st_size,
PROT_READ | ((shmflg & SHM_RDONLY) ? 0 : PROT_WRITE),
MAP_SHARED, fd, 0);
__close (fd);
if (addr == MAP_FAILED)
return (void *) -1;
err = __sysvshm_add (addr, statbuf.st_size);
if (err)
{
munmap (addr, statbuf.st_size);
errno = err;
return (void *) -1;
}
return addr;
}
weak_alias(__shmat, shmat)