MythTV: IOHandlers.cpp Source File

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00007 This library is distributed in the hope that it will be useful, but WITHOUT
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00012 You should have received a copy of the GNU Lesser General Public License
00013 along with this library; if not, write to the Free Software Foundation, Inc.,
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00016 // "mTunnel" multicast access service
00017 // Copyright (c) 1996-1998 Live Networks, Inc.  All rights reserved.
00018 // IO event handlers
00019 // Implementation
00020 
00021 #include "IOHandlers.hh"
00022 #include "TunnelEncaps.hh"
00023 
00024 //##### TEMP: Use a single buffer, sized for UDP tunnels:
00025 //##### This assumes that the I/O handlers are non-reentrant
00026 static unsigned const maxPacketLength = 50*1024; // bytes
00027     // This is usually overkill, because UDP packets are usually no larger
00028     // than the typical Ethernet MTU (1500 bytes).  However, I've seen
00029     // reports of Windows Media Servers sending UDP packets as large as
00030     // 27 kBytes.  These will probably undego lots of IP-level
00031     // fragmentation, but that occurs below us.  We just have to hope that
00032     // fragments don't get lost.
00033 static unsigned const ioBufferSize
00034         = maxPacketLength + TunnelEncapsulationTrailerMaxSize;
00035 static unsigned char ioBuffer[ioBufferSize];
00036 
00037 
00038 void socketReadHandler(Socket* sock, int /*mask*/) {
00039   unsigned bytesRead;
00040   struct sockaddr_in fromAddress;
00041   UsageEnvironment& saveEnv = sock->env();
00042       // because handleRead(), if it fails, may delete "sock"
00043   if (!sock->handleRead(ioBuffer, ioBufferSize, bytesRead, fromAddress)) {
00044     saveEnv.reportBackgroundError();
00045   }
00046 }