65 lines
1.6 KiB
C++
65 lines
1.6 KiB
C++
/*
|
|
* \brief Make dataspace accessible to other Linux processes
|
|
* \author Norman Feske
|
|
* \date 2006-07-03
|
|
*/
|
|
|
|
/*
|
|
* Copyright (C) 2006-2013 Genode Labs GmbH
|
|
*
|
|
* This file is part of the Genode OS framework, which is distributed
|
|
* under the terms of the GNU General Public License version 2.
|
|
*/
|
|
|
|
/* glibc includes */
|
|
#include <fcntl.h>
|
|
|
|
/* Genode includes */
|
|
#include <base/snprintf.h>
|
|
|
|
/* local includes */
|
|
#include <ram_session_component.h>
|
|
#include <resource_path.h>
|
|
|
|
/* Linux syscall bindings */
|
|
#include <core_linux_syscalls.h>
|
|
|
|
|
|
using namespace Genode;
|
|
|
|
|
|
static int ram_ds_cnt = 0; /* counter for creating unique dataspace IDs */
|
|
|
|
void Ram_session_component::_export_ram_ds(Dataspace_component *ds)
|
|
{
|
|
char fname[Linux_dataspace::FNAME_LEN];
|
|
|
|
/* create file using a unique file name in the resource path */
|
|
snprintf(fname, sizeof(fname), "%s/ds-%d", resource_path(), ram_ds_cnt++);
|
|
lx_unlink(fname);
|
|
int const fd = lx_open(fname, O_CREAT|O_RDWR|O_TRUNC|LX_O_CLOEXEC, S_IRWXU);
|
|
lx_ftruncate(fd, ds->size());
|
|
|
|
/* remember file descriptor in dataspace component object */
|
|
ds->fd(fd);
|
|
|
|
/*
|
|
* Wipe the file from the Linux file system. The kernel will still keep the
|
|
* then unnamed file around until the last reference to the file will be
|
|
* gone (i.e., an open file descriptor referring to the file). A process
|
|
* w/o the right file descriptor won't be able to open and access the file.
|
|
*/
|
|
lx_unlink(fname);
|
|
}
|
|
|
|
|
|
void Ram_session_component::_revoke_ram_ds(Dataspace_component *ds)
|
|
{
|
|
int const fd = ds->fd().dst().socket;
|
|
if (fd != -1)
|
|
lx_close(fd);
|
|
}
|
|
|
|
|
|
void Ram_session_component::_clear_ds(Dataspace_component *ds) { }
|