utils/wvshmzone.cc

   1 /*
   2  * Worldvisions Weaver Software:
   3  *   Copyright (C) 1997-2002 Net Integration Technologies, Inc.
   4  *
   5  * A shared-memory zone via mmap().  See wvshmzone.h.
   6  */
   7 #include "wvshmzone.h"
   8 #include <sys/mman.h>
   9 #include <sys/types.h>
  10 #include <sys/stat.h>
  11 #include <fcntl.h>
  12 #include <assert.h>
  13 #include <errno.h>
  14 #include <unistd.h>
  15
  16 WvShmZone::WvShmZone(size_t _size)
  17 {
  18     size = (int)_size;
  19     assert(size > 0);
  20
  21     buf = NULL;
  22
  23     fd = open("/dev/zero", O_RDWR);
  24     if (fd < 0)
  25     {
  26         seterr(errno);
  27         return;
  28     }
  29
  30     buf = mmap(0, size, PROT_READ|PROT_WRITE, MAP_SHARED, fd, 0);
  31
  32     if (!buf)
  33     {
  34         seterr(errno);
  35         return;
  36     }
  37 }
  38
  39
  40 WvShmZone::~WvShmZone()
  41 {
  42     if (buf)
  43         munmap(buf, size);
  44     if (fd >= 0)
  45         close(fd);
  46 }
  47
  48