bitbake: fetch2/__init__.py: Add FetchConnectionCache class

FetchConnectionCache class acts as a container for socket connections
useful when implement connection cache into fetcher modules.

(Bitbake rev: 454da2cd17539ceb9caad6d76f034757e44ee12f)

Signed-off-by: Aníbal Limón <anibal.limon@linux.intel.com>
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>

bitbake/lib/bb/fetch2/__init__.py

@@ -1711,6 +1711,42 @@ class Fetch(object):
             if ud.lockfile:
                 bb.utils.unlockfile(lf)
 
+class FetchConnectionCache(object):
+    """
+        A class which represents an container for socket connections.
+    """
+    def __init__(self):
+        self.cache = {}
+
+    def get_connection_name(self, host, port):
+        return host + ':' + str(port)
+
+    def add_connection(self, host, port, connection):
+        cn = self.get_connection_name(host, port)
+
+        if cn not in self.cache:
+            self.cache[cn] = connection
+
+    def get_connection(self, host, port):
+        connection = None
+
+        cn = self.get_connection_name(host, port)
+        if cn in self.cache:
+            connection = self.cache[cn]
+
+        return connection
+
+    def remove_connection(self, host, port):
+        cn = self.get_connection_name(host, port)
+        if cn in self.cache:
+            self.cache[cn].close()
+            del self.cache[cn]
+
+    def close_connections(self):
+        for cn in self.cache.keys():
+            self.cache[cn].close()
+            del self.cache[cn]
+
 from . import cvs
 from . import git
 from . import gitsm