Initial commit moving openolt adapter from voltha-go to the new repo.
This version works with ponsim rather than openolt, this is temporary.
It is currently being fixed to work with openolt.

Change-Id: I34a800c98f050140b367e2d474b7aa8b79f34b9a
Signed-off-by: William Kurkian <wkurkian@cisco.com>
diff --git a/python/common/utils/indexpool.py b/python/common/utils/indexpool.py
new file mode 100644
index 0000000..858cb3a
--- /dev/null
+++ b/python/common/utils/indexpool.py
@@ -0,0 +1,64 @@
+# Copyright 2017-present Open Networking Foundation
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+# http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+from bitstring import BitArray
+import structlog
+
+log = structlog.get_logger()
+
+class IndexPool(object):
+    def __init__(self, max_entries, offset):
+        self.max_entries = max_entries
+        self.offset = offset
+        self.indices = BitArray(self.max_entries)
+
+    def get_next(self):
+        try:
+            _pos = self.indices.find('0b0')
+            self.indices.set(1, _pos)
+            return self.offset + _pos[0]
+        except IndexError:
+            log.info("exception-fail-to-allocate-id-all-bits-in-use")
+            return None
+
+    def allocate(self, index):
+        try:
+            _pos = index - self.offset
+            if not (0 <= _pos < self.max_entries):
+                log.info("{}-out-of-range".format(index))
+                return None
+            if self.indices[_pos]:
+                log.info("{}-is-already-allocated".format(index))
+                return None
+            self.indices.set(1, _pos)
+            return index
+
+        except IndexError:
+            return None
+
+    def release(self, index):
+        index -= self.offset
+        _pos = (index,)
+        try:
+            self.indices.set(0, _pos)
+        except IndexError:
+            log.info("bit-position-{}-out-of-range".format(index))
+
+    #index or multiple indices to set all of them to 1 - need to be a tuple
+    def pre_allocate(self, index):
+        if(isinstance(index, tuple)):
+            _lst = list(index)
+            for i in range(len(_lst)):
+                _lst[i] -= self.offset
+            index = tuple(_lst)
+            self.indices.set(1, index)