1 kumpf 1.1.4.2 /*
  2               //%2006////////////////////////////////////////////////////////////////////////
  3               //
  4               // Copyright (c) 2000, 2001, 2002 BMC Software; Hewlett-Packard Development
  5               // Company, L.P.; IBM Corp.; The Open Group; Tivoli Systems.
  6               // Copyright (c) 2003 BMC Software; Hewlett-Packard Development Company, L.P.;
  7               // IBM Corp.; EMC Corporation, The Open Group.
  8               // Copyright (c) 2004 BMC Software; Hewlett-Packard Development Company, L.P.;
  9               // IBM Corp.; EMC Corporation; VERITAS Software Corporation; The Open Group.
 10               // Copyright (c) 2005 Hewlett-Packard Development Company, L.P.; IBM Corp.;
 11               // EMC Corporation; VERITAS Software Corporation; The Open Group.
 12               // Copyright (c) 2006 Hewlett-Packard Development Company, L.P.; IBM Corp.;
 13               // EMC Corporation; Symantec Corporation; The Open Group.
 14               //
 15               // Permission is hereby granted, free of charge, to any person obtaining a copy
 16               // of this software and associated documentation files (the "Software"), to
 17               // deal in the Software without restriction, including without limitation the
 18               // rights to use, copy, modify, merge, publish, distribute, sublicense, and/or
 19               // sell copies of the Software, and to permit persons to whom the Software is
 20               // furnished to do so, subject to the following conditions:
 21               // 
 22 kumpf 1.1.4.2 // THE ABOVE COPYRIGHT NOTICE AND THIS PERMISSION NOTICE SHALL BE INCLUDED IN
 23               // ALL COPIES OR SUBSTANTIAL PORTIONS OF THE SOFTWARE. THE SOFTWARE IS PROVIDED
 24               // "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT
 25               // LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR
 26               // PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT
 27               // HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
 28               // ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
 29               // WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
 30               //
 31               //%/////////////////////////////////////////////////////////////////////////////
 32               */
 33               
 34               #ifndef _Executor_Socket_h
 35               #define _Executor_Socket_h
 36               
 37               #include <stdlib.h>
 38               #include "Defines.h"
 39               #include <sys/socket.h>
 40               #include <string.h>
 41               #include "Defines.h"
 42               
 43 kumpf 1.1.4.2 EXECUTOR_LINKAGE
 44               int SetNonBlocking(int sock);
 45               
 46               EXECUTOR_LINKAGE
 47               int SetBlocking(int sock);
 48               
 49               EXECUTOR_LINKAGE
 50               ssize_t RecvNonBlock(int sock, void* buffer, size_t size);
 51               
 52               EXECUTOR_LINKAGE
 53               ssize_t SendNonBlock(int sock, const void* buffer, size_t size);
 54               
 55               EXECUTOR_LINKAGE
 56               int CloseOnExec(int fd);
 57               
 58               EXECUTOR_LINKAGE
 59               ssize_t SendDescriptorArray(int sock, int descriptors[], size_t count);
 60               
 61               EXECUTOR_LINKAGE
 62               int CreateSocketPair(int pair[2]);
 63               
 64 kumpf 1.1.4.2 static int RecvDescriptorArray(int sock, int descriptors[], size_t count)
 65               {
 66                   struct iovec iov[1];
 67                   char dummy;
 68                   struct msghdr mh;
 69                   ssize_t n;
 70               #if defined(HAVE_MSG_CONTROL)
 71                   size_t size;
 72                   char* data;
 73                   struct cmsghdr* cmh = CMSG_FIRSTHDR(&mh);
 74               
 75                   /*
 76                    * This control data begins with a cmsghdr struct followed by the data
 77                    * (a descriptor in this case). The union ensures that the data is 
 78                    * aligned suitably for the leading cmsghdr struct. The descriptor 
 79                    * itself is properly aligned since the cmsghdr ends on a boundary 
 80                    * that is suitably aligned for any type (including int).
 81                    *
 82                    *     ControlData = [ cmsghdr | int ]
 83                    */
 84               
 85 kumpf 1.1.4.2     size = CMSG_SPACE(sizeof(int) * count);
 86                   data = (char*)malloc(size);
 87               
 88                   /* Define a msghdr that refers to the control data, which is filled in
 89                    * by calling recvmsg() below.
 90                    */
 91               
 92                   memset(&mh, 0, sizeof(mh));
 93                   mh.msg_control = data;
 94                   mh.msg_controllen = size;
 95               
 96               #else /* !defined(HAVE_MSG_CONTROL) */
 97               
 98                   memset(&mh, 0, sizeof(mh));
 99                   mh.msg_accrights = (caddr_t)descriptors;
100                   mh.msg_accrightslen = sizeof(int) * count;
101               
102               #endif /* defined(HAVE_MSG_CONTROL) */
103               
104                   /*
105                    * The other process sends a single-byte message. This byte is not
106 kumpf 1.1.4.2      * used since we only need the control data (the descriptor) but we
107                    * must request at least one byte from recvmsg().
108                    */
109               
110                   memset(iov, 0, sizeof(iov));
111                   iov[0].iov_base = &dummy;
112                   iov[0].iov_len = 1;
113                   mh.msg_iov = iov;
114                   mh.msg_iovlen = 1;
115               
116                   /* Receive the message from the other process. */
117               
118                   n = recvmsg(sock, &mh, 0);
119               
120                   if (n <= 0)
121                       return -1;
122               
123                   /* Get a pointer to control message. Return if the header is null or 
124                    * does not contain what we expect.
125                    */
126               
127 kumpf 1.1.4.2 #if defined(HAVE_MSG_CONTROL)
128               
129                   cmh = CMSG_FIRSTHDR(&mh);
130               
131                   if (!cmh || 
132                       cmh->cmsg_len != CMSG_LEN(sizeof(int) * count) ||
133                       cmh->cmsg_level != SOL_SOCKET ||
134                       cmh->cmsg_type != SCM_RIGHTS)
135                   {
136                       return -1;
137                   }
138               
139                   /* Copy the data: */
140               
141                   memcpy(descriptors, CMSG_DATA(cmh), sizeof(int) * count);
142               
143               #else /* !defined(HAVE_MSG_CONTROL) */
144               
145                   if (mh.msg_accrightslen != sizeof(int) * count)
146                       return -1;
147               
148 kumpf 1.1.4.2     memcpy(descriptors, mh.msg_accrights, sizeof(int) * count);
149               
150               #endif /* defined(HAVE_MSG_CONTROL) */
151               
152                   return 0;
153               }
154               
155               #endif /* _Executor_Socket_h */