Bug #275047 - Split _emerge/__init__.py into smaller pieces. Thanks to

Sebastian Mingramm (few) <s.mingramm@gmx.de> for this patch.

svn path=/main/trunk/; revision=13663

1 files changed, 98 insertions, 0 deletions

diff --git a/pym/_emerge/PipeReader.py b/pym/_emerge/PipeReader.py
new file mode 100644
index 000000000..4b2e2f141
--- /dev/null
+++ b/pym/_emerge/PipeReader.py
@@ -0,0 +1,98 @@
+from _emerge.AbstractPollTask import AbstractPollTask
+from _emerge.PollConstants import PollConstants
+import sys
+import os
+import fcntl
+import array
+class PipeReader(AbstractPollTask):
+
+	"""
+	Reads output from one or more files and saves it in memory,
+	for retrieval via the getvalue() method. This is driven by
+	the scheduler's poll() loop, so it runs entirely within the
+	current process.
+	"""
+
+	__slots__ = ("input_files",) + \
+		("_read_data", "_reg_ids")
+
+	def _start(self):
+		self._reg_ids = set()
+		self._read_data = []
+		for k, f in self.input_files.iteritems():
+			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 = True
+
+	def isAlive(self):
+		return self._registered
+
+	def cancel(self):
+		if self.returncode is None:
+			self.returncode = 1
+			self.cancelled = True
+		self.wait()
+
+	def _wait(self):
+		if self.returncode is not None:
+			return self.returncode
+
+		if self._registered:
+			self.scheduler.schedule(self._reg_ids)
+			self._unregister()
+
+		self.returncode = os.EX_OK
+		return self.returncode
+
+	def getvalue(self):
+		"""Retrieve the entire contents"""
+		if sys.hexversion >= 0x3000000:
+			return bytes().join(self._read_data)
+		return "".join(self._read_data)
+
+	def close(self):
+		"""Free the memory buffer."""
+		self._read_data = None
+
+	def _output_handler(self, fd, event):
+
+		if event & PollConstants.POLLIN:
+
+			for f in self.input_files.itervalues():
+				if fd == f.fileno():
+					break
+
+			buf = array.array('B')
+			try:
+				buf.fromfile(f, self._bufsize)
+			except EOFError:
+				pass
+
+			if buf:
+				self._read_data.append(buf.tostring())
+			else:
+				self._unregister()
+				self.wait()
+
+		self._unregister_if_appropriate(event)
+		return self._registered
+
+	def _unregister(self):
+		"""
+		Unregister from the scheduler and close open files.
+		"""
+
+		self._registered = False
+
+		if self._reg_ids is not None:
+			for reg_id in self._reg_ids:
+				self.scheduler.unregister(reg_id)
+			self._reg_ids = None
+
+		if self.input_files is not None:
+			for f in self.input_files.itervalues():
+				f.close()
+			self.input_files = None
+