Handle OSError from os.read and loop if needed.

Looping fixes EbuildMetadataPhase failures for ebuilds that produce
more than 4096 bytes of metadata, broken since commit
b432a1b3051d91546649e8f3190675767461d8e8.

3 files changed, 29 insertions, 23 deletions

diff --git a/pym/_emerge/AsynchronousLock.py b/pym/_emerge/AsynchronousLock.py
index 39e36c880..9d0545beb 100644
--- a/pym/_emerge/AsynchronousLock.py
+++ b/pym/_emerge/AsynchronousLock.py
@@ -138,7 +138,7 @@ class _LockThread(AbstractPollTask):
 		if event & PollConstants.POLLIN:
 			try:
 				buf = os.read(self._files['pipe_read'], self._bufsize)
-			except IOError as e:
+			except OSError as e:
 				if e.errno not in (errno.EAGAIN,):
 					raise
 		if buf:
@@ -274,7 +274,7 @@ class _LockProcess(AbstractPollTask):
 		if event & PollConstants.POLLIN:
 			try:
 				buf = os.read(self._files['pipe_in'], self._bufsize)
-			except IOError as e:
+			except OSError as e:
 				if e.errno not in (errno.EAGAIN,):
 					raise
 		if buf:
diff --git a/pym/_emerge/EbuildMetadataPhase.py b/pym/_emerge/EbuildMetadataPhase.py
index e068e8f24..d4f5bc009 100644
--- a/pym/_emerge/EbuildMetadataPhase.py
+++ b/pym/_emerge/EbuildMetadataPhase.py
@@ -112,16 +112,19 @@ class EbuildMetadataPhase(SubProcess):
 	def _output_handler(self, fd, event):
 
 		if event & PollConstants.POLLIN:
-			try:
-				self._raw_metadata.append(
-					os.read(self._files.ebuild, self._bufsize))
-			except IOError as e:
-				if e.errno not in (errno.EAGAIN,):
-					raise
-			else:
-				if not self._raw_metadata[-1]:
-					self._unregister()
-					self.wait()
+			while True:
+				try:
+					self._raw_metadata.append(
+						os.read(self._files.ebuild, self._bufsize))
+				except OSError as e:
+					if e.errno not in (errno.EAGAIN,):
+						raise
+					break
+				else:
+					if not self._raw_metadata[-1]:
+						self._unregister()
+						self.wait()
+						break
 
 		self._unregister_if_appropriate(event)
 
diff --git a/pym/_emerge/PipeReader.py b/pym/_emerge/PipeReader.py
index 67144c393..af8cfdd4e 100644
--- a/pym/_emerge/PipeReader.py
+++ b/pym/_emerge/PipeReader.py
@@ -59,18 +59,21 @@ class PipeReader(AbstractPollTask):
 
 		if event & PollConstants.POLLIN:
 
-			data = None
-			try:
-				data = os.read(fd, self._bufsize)
-			except IOError as e:
-				if e.errno not in (errno.EAGAIN,):
-					raise
-			else:
-				if data:
-					self._read_data.append(data)
+			while True:
+				data = None
+				try:
+					data = os.read(fd, self._bufsize)
+				except OSError as e:
+					if e.errno not in (errno.EAGAIN,):
+						raise
+					break
 				else:
-					self._unregister()
-					self.wait()
+					if data:
+						self._read_data.append(data)
+					else:
+						self._unregister()
+						self.wait()
+						break
 
 		self._unregister_if_appropriate(event)