minix/lib/sysvipc/shm.c
2010-01-26 10:59:01 +00:00

107 lines
1.9 KiB
C

#define _SYSTEM 1
#define _MINIX 1
#include <minix/com.h>
#include <minix/config.h>
#include <minix/ipc.h>
#include <minix/endpoint.h>
#include <minix/sysutil.h>
#include <minix/const.h>
#include <minix/type.h>
#include <minix/rs.h>
#include <lib.h>
#include <sys/types.h>
#include <sys/ipc.h>
#include <sys/shm.h>
#include <stdlib.h>
#include <errno.h>
PRIVATE int get_ipc_endpt(endpoint_t *pt)
{
return minix_rs_lookup("ipc", pt);
}
/* Shared memory control operation. */
PUBLIC int shmctl(int shmid, int cmd, struct shmid_ds *buf)
{
message m;
endpoint_t ipc_pt;
int r;
if (get_ipc_endpt(&ipc_pt) != OK) {
errno = ENOSYS;
return -1;
}
m.SHMCTL_ID = shmid;
m.SHMCTL_CMD = cmd;
m.SHMCTL_BUF = (long) buf;
r = _syscall(ipc_pt, IPC_SHMCTL, &m);
if ((cmd == IPC_INFO || cmd == SHM_INFO || cmd == SHM_STAT)
&& (r == OK))
return m.SHMCTL_RET;
return r;
}
/* Get shared memory segment. */
PUBLIC int shmget(key_t key, size_t size, int shmflg)
{
message m;
endpoint_t ipc_pt;
int r;
if (get_ipc_endpt(&ipc_pt) != OK) {
errno = ENOSYS;
return -1;
}
m.SHMGET_KEY = key;
m.SHMGET_SIZE = size;
m.SHMGET_FLAG = shmflg;
r = _syscall(ipc_pt, IPC_SHMGET, &m);
if (r != OK)
return r;
return m.SHMGET_RETID;
}
/* Attach shared memory segment. */
PUBLIC void *shmat(int shmid, const void *shmaddr, int shmflg)
{
message m;
endpoint_t ipc_pt;
int r;
if (get_ipc_endpt(&ipc_pt) != OK) {
errno = ENOSYS;
return NULL;
}
m.SHMAT_ID = shmid;
m.SHMAT_ADDR = (long) shmaddr;
m.SHMAT_FLAG = shmflg;
r = _syscall(ipc_pt, IPC_SHMAT, &m);
if (r != OK)
return (void *) -1;
return (void *) m.SHMAT_RETADDR;
}
/* Deattach shared memory segment. */
PUBLIC int shmdt(const void *shmaddr)
{
message m;
endpoint_t ipc_pt;
if (get_ipc_endpt(&ipc_pt) != OK) {
errno = ENOSYS;
return -1;
}
m.SHMDT_ADDR = (long) shmaddr;
return _syscall(ipc_pt, IPC_SHMDT, &m);
}