lib/libc/sys-minix/shmat.c

   1 #define _SYSTEM 1
   2 #define _MINIX 1
   3
   4 #include <sys/cdefs.h>
   5 #include <lib.h>
   6 #include "namespace.h"
   7
   8 #include <minix/rs.h>
   9
  10 #include <lib.h>
  11 #include <sys/types.h>
  12 #include <sys/ipc.h>
  13 #include <sys/shm.h>
  14 #include <stdlib.h>
  15 #include <errno.h>
  16
  17 #ifdef __weak_alias
  18 __weak_alias(shmat, _shmat)
  19 __weak_alias(shmdt, _shmdt)
  20 #endif
  21
  22
  23 static int get_ipc_endpt(endpoint_t *pt)
  24 {
  25         return minix_rs_lookup("ipc", pt);
  26 }
  27
  28 /* Attach shared memory segment. */
  29 void *shmat(int shmid, const void *shmaddr, int shmflg)
  30 {
  31         message m;
  32         endpoint_t ipc_pt;
  33         int r;
  34
  35         if (get_ipc_endpt(&ipc_pt) != OK) {
  36                 errno = ENOSYS;
  37                 return NULL;
  38         }
  39
  40         m.SHMAT_ID = shmid;
  41         m.SHMAT_ADDR = (long) shmaddr;
  42         m.SHMAT_FLAG = shmflg;
  43
  44         r = _syscall(ipc_pt, IPC_SHMAT, &m);
  45         if (r != OK)
  46                 return (void *) -1;
  47         return (void *) m.SHMAT_RETADDR;
  48 }
  49
  50 /* Deattach shared memory segment. */
  51 int shmdt(const void *shmaddr)
  52 {
  53         message m;
  54         endpoint_t ipc_pt;
  55
  56         if (get_ipc_endpt(&ipc_pt) != OK) {
  57                 errno = ENOSYS;
  58                 return -1;
  59         }
  60
  61         m.SHMDT_ADDR = (long) shmaddr;
  62
  63         return _syscall(ipc_pt, IPC_SHMDT, &m);
  64 }
  65