Merge pull request gitpython-developers#58 from sugi/cmd-fd-leak-fix

Fixes on cmd.py (fd leak and signal exception)

Currently if command is called with as_proces=True, pipes for the
command will not be closed.

cb68f36 makes sure to close command file descriptors.
Ignore signal exception on AutoInterrupt destructor.

When command run as subprocess, AutoInterrupt will kill the
process on destructor. However, if process already finished,
it raise OSError exception.

Author: Byron

git/cmd.py

@@ -73,6 +73,9 @@ def __init__(self, proc, args ):
 			self.args = args
 
 		def __del__(self):
+			self.proc.stdout.close()
+			self.proc.stderr.close()
+
 			# did the process finish already so we have a return code ?
 			if self.proc.poll() is not None:
 				return
@@ -84,6 +87,8 @@ def __del__(self):
 			# try to kill it
 			try:
 				os.kill(self.proc.pid, 2)	# interrupt signal
+			except OSError:
+			    pass # ignore error when process already died
 			except AttributeError:
 				# try windows 
 				# for some reason, providing None for stdout/stderr still prints something. This is why 
@@ -100,6 +105,8 @@ def wait(self):
 			
 			:raise GitCommandError: if the return status is not 0"""
 			status = self.proc.wait()
+			self.proc.stdout.close()
+			self.proc.stderr.close()
 			if status != 0:
 				raise GitCommandError(self.args, status, self.proc.stderr.read())
 			# END status handling