glibc/sysdeps/unix/sysv/linux/shmat.c

47 lines
1.6 KiB
C

/* Copyright (C) 1995-2020 Free Software Foundation, Inc.
This file is part of the GNU C Library.
Contributed by Ulrich Drepper <drepper@gnu.ai.mit.edu>, August 1995.
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 <sys/msg.h>
#include <ipc_priv.h>
#include <sysdep.h>
#include <errno.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)
{
#ifdef __ASSUME_DIRECT_SYSVIPC_SYSCALLS
return (void*) INLINE_SYSCALL_CALL (shmat, shmid, shmaddr, shmflg);
#else
INTERNAL_SYSCALL_DECL(err);
unsigned long resultvar;
void *raddr;
resultvar = INTERNAL_SYSCALL_CALL (ipc, err, IPCOP_shmat, shmid, shmflg,
&raddr, shmaddr);
if (INTERNAL_SYSCALL_ERROR_P (resultvar, err))
return (void *) INLINE_SYSCALL_ERROR_RETURN_VALUE (INTERNAL_SYSCALL_ERRNO (resultvar,
err));
return raddr;
#endif
}