test_poll: fix array test

Since SpawnProcess no longer uses array, add conditional array support
to PipeReader and use that for tests.

2 files changed, 76 insertions, 2 deletions

diff --git a/pym/_emerge/AbstractPollTask.py b/pym/_emerge/AbstractPollTask.py
index b3c0b2d16..83e6c7b9c 100644
--- a/pym/_emerge/AbstractPollTask.py
+++ b/pym/_emerge/AbstractPollTask.py
@@ -1,6 +1,7 @@
 # Copyright 1999-2011 Gentoo Foundation
 # Distributed under the terms of the GNU General Public License v2
 
+import array
 import errno
 import logging
 import os
@@ -21,6 +22,54 @@ class AbstractPollTask(AsynchronousTask):
 	def isAlive(self):
 		return bool(self._registered)
 
+	def _read_array(self, f, event):
+		"""
+		NOTE: array.fromfile() is used here only for testing purposes,
+		because it has bugs in all known versions of Python (including
+		Python 2.7 and Python 3.2).
+
+		| POLLIN | RETURN
+		| BIT    | VALUE
+		| ---------------------------------------------------
+		| 1      | Read self._bufsize into an instance of
+		|        | array.array('B') and return it, ignoring
+		|        | EOFError and IOError. An empty array
+		|        | indicates EOF.
+		| ---------------------------------------------------
+		| 0      | None
+		"""
+		buf = None
+		if event & PollConstants.POLLIN:
+			buf = array.array('B')
+			try:
+				buf.fromfile(f, self._bufsize)
+			except EOFError:
+				pass
+			except TypeError:
+				# Python 3.2:
+				# TypeError: read() didn't return bytes
+				pass
+			except IOError as e:
+				# EIO happens with pty on Linux after the
+				# slave end of the pty has been closed.
+				if e.errno == errno.EIO:
+					# EOF: return empty string of bytes
+					pass
+				elif e.errno == errno.EAGAIN:
+					# EAGAIN: return None
+					buf = None
+				else:
+					raise
+
+		if buf is not None:
+			try:
+				# Python >=3.2
+				buf = buf.tobytes()
+			except AttributeError:
+				buf = buf.tostring()
+
+		return buf
+
 	def _read_buf(self, fd, event):
 		"""
 		| POLLIN | RETURN
diff --git a/pym/_emerge/PipeReader.py b/pym/_emerge/PipeReader.py
index 9fedbff6f..b162fe5cc 100644
--- a/pym/_emerge/PipeReader.py
+++ b/pym/_emerge/PipeReader.py
@@ -15,16 +15,22 @@ class PipeReader(AbstractPollTask):
 	"""
 
 	__slots__ = ("input_files",) + \
-		("_read_data", "_reg_ids")
+		("_read_data", "_reg_ids", "_use_array")
 
 	def _start(self):
 		self._reg_ids = set()
 		self._read_data = []
+
+		if self._use_array:
+			output_handler = self._array_output_handler
+		else:
+			output_handler = self._output_handler
+
 		for k, f in self.input_files.items():
 			fcntl.fcntl(f.fileno(), fcntl.F_SETFL,
 				fcntl.fcntl(f.fileno(), fcntl.F_GETFL) | os.O_NONBLOCK)
 			self._reg_ids.add(self.scheduler.register(f.fileno(),
-				self._registered_events, self._output_handler))
+				self._registered_events, output_handler))
 		self._registered = True
 
 	def isAlive(self):
@@ -68,6 +74,25 @@ class PipeReader(AbstractPollTask):
 
 		self._unregister_if_appropriate(event)
 
+	def _array_output_handler(self, fd, event):
+
+		for f in self.input_files.values():
+			if f.fileno() == fd:
+				break
+
+		while True:
+			data = self._read_array(f, event)
+			if data is None:
+				break
+			if data:
+				self._read_data.append(data)
+			else:
+				self._unregister()
+				self.wait()
+				break
+
+		self._unregister_if_appropriate(event)
+
 	def _unregister(self):
 		"""
 		Unregister from the scheduler and close open files.