o New port py-kenosis version 0.92: A fully-distributed p2p RPC

  system built on top of XMLRPC
o This version of kenosis works only with python 2.3 due to changes
  on Queue.py API. Therefore, to make it compatible with pythong
  2.4, a copy of Queue.py from python 2.3 is bundled with this port
  for the time being

Reviewed by:	Eric Ries <eric.ries@aya.yale.edu> (kenosis developer)

2 files changed, 217 insertions, 0 deletions

diff --git a/net-p2p/py-kenosis/files/patch-kenosis_setup.py b/net-p2p/py-kenosis/files/patch-kenosis_setup.py
new file mode 100644
index 000000000000..32ab818eaddf
--- /dev/null
+++ b/net-p2p/py-kenosis/files/patch-kenosis_setup.py
@@ -0,0 +1,11 @@
+--- kenosis_setup.py.orig	Fri Jan  7 04:16:32 2005
++++ kenosis_setup.py	Thu Jan 13 00:22:56 2005
+@@ -15,7 +15,6 @@
+     url = "http://kenosis.sf.net/",
+     license = "MIT",
+     
+-    packages = ["bt", "bt.BitTorrent", "ds", "kenosis", "kenosis.dns"],
++    packages = ["kenosis", "kenosis.ds", "kenosis.dns"],
+     )
+ 
+-print("Upload to upload.sf.net/incoming by running: ncftpput upload.sf.net incoming dist/kenosis-%s.tar.gz" % kenosis.version)
diff --git a/net-p2p/py-kenosis/files/python2.3-Queue.py b/net-p2p/py-kenosis/files/python2.3-Queue.py
new file mode 100644
index 000000000000..980aee619ddc
--- /dev/null
+++ b/net-p2p/py-kenosis/files/python2.3-Queue.py
@@ -0,0 +1,206 @@
+"""A multi-producer, multi-consumer queue."""
+
+from time import time as _time, sleep as _sleep
+
+__all__ = ['Empty', 'Full', 'Queue']
+
+class Empty(Exception):
+    "Exception raised by Queue.get(block=0)/get_nowait()."
+    pass
+
+class Full(Exception):
+    "Exception raised by Queue.put(block=0)/put_nowait()."
+    pass
+
+class Queue:
+    def __init__(self, maxsize=0):
+        """Initialize a queue object with a given maximum size.
+
+        If maxsize is <= 0, the queue size is infinite.
+        """
+        try:
+            import thread
+        except ImportError:
+            import dummy_thread as thread
+        self._init(maxsize)
+        self.mutex = thread.allocate_lock()
+        self.esema = thread.allocate_lock()
+        self.esema.acquire()
+        self.fsema = thread.allocate_lock()
+
+    def qsize(self):
+        """Return the approximate size of the queue (not reliable!)."""
+        self.mutex.acquire()
+        n = self._qsize()
+        self.mutex.release()
+        return n
+
+    def empty(self):
+        """Return True if the queue is empty, False otherwise (not reliable!)."""
+        self.mutex.acquire()
+        n = self._empty()
+        self.mutex.release()
+        return n
+
+    def full(self):
+        """Return True if the queue is full, False otherwise (not reliable!)."""
+        self.mutex.acquire()
+        n = self._full()
+        self.mutex.release()
+        return n
+
+    def put(self, item, block=True, timeout=None):
+        """Put an item into the queue.
+
+        If optional args 'block' is true and 'timeout' is None (the default),
+        block if necessary until a free slot is available. If 'timeout' is
+        a positive number, it blocks at most 'timeout' seconds and raises
+        the Full exception if no free slot was available within that time.
+        Otherwise ('block' is false), put an item on the queue if a free slot
+        is immediately available, else raise the Full exception ('timeout'
+        is ignored in that case).
+        """
+        if block:
+            if timeout is None:
+                # blocking, w/o timeout, i.e. forever
+                self.fsema.acquire()
+            elif timeout >= 0:
+                # waiting max. 'timeout' seconds.
+                # this code snipped is from threading.py: _Event.wait():
+                # Balancing act:  We can't afford a pure busy loop, so we
+                # have to sleep; but if we sleep the whole timeout time,
+                # we'll be unresponsive.  The scheme here sleeps very
+                # little at first, longer as time goes on, but never longer
+                # than 20 times per second (or the timeout time remaining).
+                delay = 0.0005 # 500 us -> initial delay of 1 ms
+                endtime = _time() + timeout
+                while True:
+                    if self.fsema.acquire(0):
+                        break
+                    remaining = endtime - _time()
+                    if remaining <= 0:  #time is over and no slot was free
+                        raise Full
+                    delay = min(delay * 2, remaining, .05)
+                    _sleep(delay)       #reduce CPU usage by using a sleep
+            else:
+                raise ValueError("'timeout' must be a positive number")
+        elif not self.fsema.acquire(0):
+            raise Full
+        self.mutex.acquire()
+        release_fsema = True
+        try:
+            was_empty = self._empty()
+            self._put(item)
+            # If we fail before here, the empty state has
+            # not changed, so we can skip the release of esema
+            if was_empty:
+                self.esema.release()
+            # If we fail before here, the queue can not be full, so
+            # release_full_sema remains True
+            release_fsema = not self._full()
+        finally:
+            # Catching system level exceptions here (RecursionDepth,
+            # OutOfMemory, etc) - so do as little as possible in terms
+            # of Python calls.
+            if release_fsema:
+                self.fsema.release()
+            self.mutex.release()
+
+    def put_nowait(self, item):
+        """Put an item into the queue without blocking.
+
+        Only enqueue the item if a free slot is immediately available.
+        Otherwise raise the Full exception.
+        """
+        return self.put(item, False)
+
+    def get(self, block=True, timeout=None):
+        """Remove and return an item from the queue.
+
+        If optional args 'block' is true and 'timeout' is None (the default),
+        block if necessary until an item is available. If 'timeout' is
+        a positive number, it blocks at most 'timeout' seconds and raises
+        the Empty exception if no item was available within that time.
+        Otherwise ('block' is false), return an item if one is immediately
+        available, else raise the Empty exception ('timeout' is ignored
+        in that case).
+        """
+        if block:
+            if timeout is None:
+                # blocking, w/o timeout, i.e. forever
+                self.esema.acquire()
+            elif timeout >= 0:
+                # waiting max. 'timeout' seconds.
+                # this code snipped is from threading.py: _Event.wait():
+                # Balancing act:  We can't afford a pure busy loop, so we
+                # have to sleep; but if we sleep the whole timeout time,
+                # we'll be unresponsive.  The scheme here sleeps very
+                # little at first, longer as time goes on, but never longer
+                # than 20 times per second (or the timeout time remaining).
+                delay = 0.0005 # 500 us -> initial delay of 1 ms
+                endtime = _time() + timeout
+                while 1:
+                    if self.esema.acquire(0):
+                        break
+                    remaining = endtime - _time()
+                    if remaining <= 0:  #time is over and no element arrived
+                        raise Empty
+                    delay = min(delay * 2, remaining, .05)
+                    _sleep(delay)       #reduce CPU usage by using a sleep
+            else:
+                raise ValueError("'timeout' must be a positive number")
+        elif not self.esema.acquire(0):
+            raise Empty
+        self.mutex.acquire()
+        release_esema = True
+        try:
+            was_full = self._full()
+            item = self._get()
+            # If we fail before here, the full state has
+            # not changed, so we can skip the release of fsema
+            if was_full:
+                self.fsema.release()
+            # Failure means empty state also unchanged - release_esema
+            # remains True.
+            release_esema = not self._empty()
+        finally:
+            if release_esema:
+                self.esema.release()
+            self.mutex.release()
+        return item
+
+    def get_nowait(self):
+        """Remove and return an item from the queue without blocking.
+
+        Only get an item if one is immediately available. Otherwise
+        raise the Empty exception.
+        """
+        return self.get(False)
+
+    # Override these methods to implement other queue organizations
+    # (e.g. stack or priority queue).
+    # These will only be called with appropriate locks held
+
+    # Initialize the queue representation
+    def _init(self, maxsize):
+        self.maxsize = maxsize
+        self.queue = []
+
+    def _qsize(self):
+        return len(self.queue)
+
+    # Check whether the queue is empty
+    def _empty(self):
+        return not self.queue
+
+    # Check whether the queue is full
+    def _full(self):
+        return self.maxsize > 0 and len(self.queue) == self.maxsize
+
+    # Put a new item in the queue
+    def _put(self, item):
+        self.queue.append(item)
+
+    # Get an item from the queue
+    def _get(self):
+        return self.queue.pop(0)