pkgs/development/tools/misc/distcc: patch distcc to use a 20 minute timeout for I/O

After having established the connection to the distcc server, time out after 20
minutes of inactivity -- rather than 5 minutes, which is too quick to build
large C++ files with complex template machinery.

svn path=/nixpkgs/trunk/; revision=19600

pkgs/development/tools/misc/distcc/20-minute-io-timeout.patch

@@ -0,0 +1,12 @@
+diff -ubr distcc-3.1-orig/src/io.c distcc-3.1-patched/src/io.c
+--- distcc-3.1-orig/src/io.c	2008-12-02 22:50:25.000000000 +0100
++++ distcc-3.1-patched/src/io.c	2010-01-07 15:07:18.000000000 +0100
+@@ -64,7 +64,7 @@
+ 
+ /** Timeout for all IO other than opening connections.  Much longer, because
+  * compiling files can take a long time. **/
+-const int dcc_io_timeout = 300; /* seconds */
++const int dcc_io_timeout = 1200; /* seconds */
+ 
+ 
+ /**

pkgs/development/tools/misc/distcc/default.nix

@@ -23,6 +23,7 @@ stdenv.mkDerivation {
                           --enable-rfc2553
                          )
   '';
+  patches = [ ./20-minute-io-timeout.patch ];
 
   # The test suite fails because it uses hard-coded paths, i.e. /usr/bin/gcc.
   doCheck = false;