src/ipc/semctl.c

   1 #include <sys/sem.h>
   2 #include <stdarg.h>
   3 #include "syscall.h"
   4 #include "ipc.h"
   5
   6 union semun {
   7         int val;
   8         struct semid_ds *buf;
   9         unsigned short *array;
  10 };
  11
  12 int semctl(int id, int num, int cmd, ...)
  13 {
  14         union semun arg = {0};
  15         va_list ap;
  16         switch (cmd) {
  17         case SETVAL: case GETALL: case SETALL: case IPC_STAT: case IPC_SET:
  18         case IPC_INFO: case SEM_INFO: case SEM_STAT:
  19                 va_start(ap, cmd);
  20                 arg = va_arg(ap, union semun);
  21                 va_end(ap);
  22         }
  23 #ifdef SYS_semctl
  24         return syscall(SYS_semctl, id, num, cmd | IPC_64, arg.buf);
  25 #else
  26         return syscall(SYS_ipc, IPCOP_semctl, id, num, cmd | IPC_64, &arg.buf);
  27 #endif
  28 }