cdsa/cdsa_utilities/fdmover.h

   1 /*
   2  * Copyright (c) 2000-2001 Apple Computer, Inc. All Rights Reserved.
   3  *
   4  * The contents of this file constitute Original Code as defined in and are
   5  * subject to the Apple Public Source License Version 1.2 (the 'License').
   6  * You may not use this file except in compliance with the License. Please obtain
   7  * a copy of the License at http://www.apple.com/publicsource and read it before
   8  * using this file.
   9  *
  10  * This Original Code and all software distributed under the License are
  11  * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER EXPRESS
  12  * OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES, INCLUDING WITHOUT
  13  * LIMITATION, ANY WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR
  14  * PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT. Please see the License for the
  15  * specific language governing rights and limitations under the License.
  16  */
  17
  18
  19 //
  20 // fdmover - send/receive file descriptors over a UNIX domain socket connection
  21 //
  22 // An FdMover object is a very specialized Socket:
  23 // It must be bound to a UNIX domain address
  24 //
  25 #ifndef _H_FDMOVER
  26 #define _H_FDMOVER
  27
  28 #include "ip++.h"
  29 #include <vector>
  30
  31 using namespace UnixPlusPlus;
  32
  33
  34 namespace Security {
  35 namespace IPPlusPlus {
  36
  37
  38 // an ordered list of file descriptors
  39 typedef std::vector<FileDesc> FdVector;
  40
  41
  42 //
  43 // An FdMover - a specialized Socket for transferring file descriptors
  44 // across UNIX domain sockets.
  45 //
  46 class FdMover : public Socket {
  47 private:
  48         class Element : public cmsghdr {
  49         public:
  50                 void *operator new (size_t base, size_t more);
  51                 void operator delete (void *addr, size_t size);
  52
  53                 Element() { }
  54                 Element(int level, int type);
  55
  56                 template <class T> T &payload() { return *reinterpret_cast<T *>(CMSG_DATA(this)); }
  57                 size_t payloadSize() const              { return cmsg_len - ((caddr_t)CMSG_DATA(this) - (caddr_t)this); }
  58         };
  59
  60         class Message : public msghdr {
  61         public:
  62                 Message(const void *data, size_t length);
  63                 void set(Element *elem);
  64                 Element *element() const                        { return (Element *)msg_control; }
  65                 Element *next(Element *elem) const      { return (Element *)CMSG_NXTHDR(this, elem); }
  66
  67         public:
  68                 IOVec iovec;
  69         };
  70
  71 public:
  72         FdMover() { }
  73         FdMover(Socket s) : Socket(s) { }
  74
  75         size_t send(const void *data, size_t length, const FdVector &fds);
  76         size_t receive(void *data, size_t length, FdVector &fds);
  77
  78 private:
  79
  80 };
  81
  82
  83 }       // end namespace IPPlusPlus
  84 }       // end namespace Security
  85
  86
  87 #endif //_H_FDMOVER