lib/libc/sys-minix/sem.c

   1 #define __USE_MISC
   2 #define _SYSTEM 1
   3 #define _MINIX 1
   4
   5 #include <sys/cdefs.h>
   6 #include <lib.h>
   7 #include "namespace.h"
   8
   9 #include <lib.h>
  10 #include <minix/rs.h>
  11
  12 #include <sys/types.h>
  13 #include <sys/ipc.h>
  14 #include <sys/sem.h>
  15 #include <stdlib.h>
  16 #include <stdarg.h>
  17 #include <errno.h>
  18
  19 static int get_ipc_endpt(endpoint_t *pt)
  20 {
  21         return minix_rs_lookup("ipc", pt);
  22 }
  23
  24 /* Get semaphore.  */
  25 int semget(key_t key, int nsems, int semflag)
  26 {
  27         message m;
  28         endpoint_t ipc_pt;
  29         int r;
  30
  31         if (get_ipc_endpt(&ipc_pt) != OK) {
  32                 errno = ENOSYS;
  33                 return -1;
  34         }
  35
  36         m.SEMGET_KEY = key;
  37         m.SEMGET_NR = nsems;
  38         m.SEMGET_FLAG = semflag;
  39
  40         r = _syscall(ipc_pt, IPC_SEMGET, &m);
  41         if (r != OK)
  42                 return r;
  43
  44         return m.SEMGET_RETID;
  45 }
  46
  47 /* Semaphore control operation.  */
  48 int semctl(int semid, int semnum, int cmd, ...)
  49 {
  50         message m;
  51         endpoint_t ipc_pt;
  52         va_list ap;
  53         int r;
  54
  55         if (get_ipc_endpt(&ipc_pt) != OK) {
  56                 errno = ENOSYS;
  57                 return -1;
  58         }
  59
  60         m.SEMCTL_ID = semid;
  61         m.SEMCTL_NUM = semnum;
  62         m.SEMCTL_CMD = cmd;
  63         va_start(ap, cmd);
  64         if (cmd == IPC_STAT || cmd == IPC_SET || cmd == IPC_INFO ||
  65                 cmd == SEM_INFO || cmd == SEM_STAT || cmd == GETALL ||
  66                 cmd == SETALL || cmd == SETVAL)
  67                 m.SEMCTL_OPT = (long) va_arg(ap, long);
  68         va_end(ap);
  69
  70         r = _syscall(ipc_pt, IPC_SEMCTL, &m);
  71         if ((r != -1) && (cmd == GETNCNT || cmd == GETZCNT || cmd == GETPID ||
  72                 cmd == GETVAL || cmd == IPC_INFO || cmd == SEM_INFO ||
  73                 cmd == SEM_STAT))
  74                 return m.SHMCTL_RET;
  75         return r;
  76 }
  77
  78 /* Operate on semaphore.  */
  79 int semop(int semid, struct sembuf *sops, size_t nsops)
  80 {
  81         message m;
  82         endpoint_t ipc_pt;
  83
  84         if (get_ipc_endpt(&ipc_pt) != OK) {
  85                 errno = ENOSYS;
  86                 return -1;
  87         }
  88
  89         m.SEMOP_ID = semid;
  90         m.SEMOP_OPS = (long) sops;
  91         m.SEMOP_SIZE = nsops;
  92
  93         return _syscall(ipc_pt, IPC_SEMOP, &m);
  94 }
  95