1 files changed, 105 insertions, 0 deletions
diff --git a/paramiko/pipe.py b/paramiko/pipe.py
new file mode 100644
index 0000000..cc28f43
--- /dev/null
+++ b/paramiko/pipe.py
@@ -0,0 +1,105 @@
+# Copyright (C) 2003-2005 Robey Pointer <robey@lag.net>
+#
+# This file is part of paramiko.
+#
+# Paramiko is free software; you can redistribute it and/or modify it under the
+# terms of the GNU Lesser General Public License as published by the Free
+# Software Foundation; either version 2.1 of the License, or (at your option)
+# any later version.
+#
+# Paramiko is distrubuted in the hope that it will be useful, but WITHOUT ANY
+# WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR
+# A PARTICULAR PURPOSE.  See the GNU Lesser General Public License for more
+# details.
+#
+# You should have received a copy of the GNU Lesser General Public License
+# along with Paramiko; if not, write to the Free Software Foundation, Inc.,
+# 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA.
+
+"""
+Abstraction of a one-way pipe where the read end can be used in select().
+Normally this is trivial, but Windows makes it nearly impossible.
+"""
+
+import sys
+import os
+import socket
+
+
+def make_pipe ():
+    if sys.platform[:3] != 'win':
+        return PosixPipe()
+    return WindowsPipe()
+
+
+class PosixPipe (object):
+    def __init__ (self):
+        self._rfd, self._wfd = os.pipe()
+        self._set = False
+        self._forever = False
+    
+    def close (self):
+        os.close(self._rfd)
+        os.close(self._wfd)
+    
+    def fileno (self):
+        return self._rfd
+
+    def clear (self):
+        if not self._set or self._forever:
+            return
+        os.read(self._rfd, 1)
+        self._set = False
+    
+    def set (self):
+        if self._set:
+            return
+        self._set = True
+        os.write(self._wfd, '*')
+    
+    def set_forever (self):
+        self._forever = True
+        self.set()
+
+
+class WindowsPipe (object):
+    """
+    On Windows, only an OS-level "WinSock" may be used in select(), but reads
+    and writes must be to the actual socket object.
+    """
+    def __init__ (self):
+        serv = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
+        serv.bind(('127.0.0.1', 0))
+        serv.listen(1)
+    
+        # need to save sockets in _rsock/_wsock so they don't get closed
+        self._rsock = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
+        self._rsock.connect(('127.0.0.1', serv.getsockname()[1]))
+    
+        self._wsock, addr = serv.accept()
+        serv.close()
+        self._set = False
+        self._forever = False
+    
+    def close (self):
+        self._rsock.close()
+        self._wsock.close()
+    
+    def fileno (self):
+        return self._rsock.fileno()
+
+    def clear (self):
+        if not self._set or self._forever:
+            return
+        self._rsock.recv(1)
+        self._set = False
+    
+    def set (self):
+        if self._set:
+            return
+        self._set = True
+        self._wsock.send('*')
+
+    def set_forever (self):
+        self._forever = True
+        self.set()