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-rw-r--r--synapse/util/lrucache.py149
1 files changed, 0 insertions, 149 deletions
diff --git a/synapse/util/lrucache.py b/synapse/util/lrucache.py
deleted file mode 100644
index cacd7e45fa..0000000000
--- a/synapse/util/lrucache.py
+++ /dev/null
@@ -1,149 +0,0 @@
-# -*- coding: utf-8 -*-
-# Copyright 2015 OpenMarket Ltd
-#
-# 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 functools import wraps
-import threading
-
-
-class LruCache(object):
-    """Least-recently-used cache."""
-    def __init__(self, max_size):
-        cache = {}
-        list_root = []
-        list_root[:] = [list_root, list_root, None, None]
-
-        PREV, NEXT, KEY, VALUE = 0, 1, 2, 3
-
-        lock = threading.Lock()
-
-        def synchronized(f):
-            @wraps(f)
-            def inner(*args, **kwargs):
-                with lock:
-                    return f(*args, **kwargs)
-
-            return inner
-
-        def add_node(key, value):
-            prev_node = list_root
-            next_node = prev_node[NEXT]
-            node = [prev_node, next_node, key, value]
-            prev_node[NEXT] = node
-            next_node[PREV] = node
-            cache[key] = node
-
-        def move_node_to_front(node):
-            prev_node = node[PREV]
-            next_node = node[NEXT]
-            prev_node[NEXT] = next_node
-            next_node[PREV] = prev_node
-            prev_node = list_root
-            next_node = prev_node[NEXT]
-            node[PREV] = prev_node
-            node[NEXT] = next_node
-            prev_node[NEXT] = node
-            next_node[PREV] = node
-
-        def delete_node(node):
-            prev_node = node[PREV]
-            next_node = node[NEXT]
-            prev_node[NEXT] = next_node
-            next_node[PREV] = prev_node
-            cache.pop(node[KEY], None)
-
-        @synchronized
-        def cache_get(key, default=None):
-            node = cache.get(key, None)
-            if node is not None:
-                move_node_to_front(node)
-                return node[VALUE]
-            else:
-                return default
-
-        @synchronized
-        def cache_set(key, value):
-            node = cache.get(key, None)
-            if node is not None:
-                move_node_to_front(node)
-                node[VALUE] = value
-            else:
-                add_node(key, value)
-                if len(cache) > max_size:
-                    delete_node(list_root[PREV])
-
-        @synchronized
-        def cache_set_default(key, value):
-            node = cache.get(key, None)
-            if node is not None:
-                return node[VALUE]
-            else:
-                add_node(key, value)
-                if len(cache) > max_size:
-                    delete_node(list_root[PREV])
-                return value
-
-        @synchronized
-        def cache_pop(key, default=None):
-            node = cache.get(key, None)
-            if node:
-                delete_node(node)
-                return node[VALUE]
-            else:
-                return default
-
-        @synchronized
-        def cache_clear():
-            list_root[NEXT] = list_root
-            list_root[PREV] = list_root
-            cache.clear()
-
-        @synchronized
-        def cache_len():
-            return len(cache)
-
-        @synchronized
-        def cache_contains(key):
-            return key in cache
-
-        self.sentinel = object()
-        self.get = cache_get
-        self.set = cache_set
-        self.setdefault = cache_set_default
-        self.pop = cache_pop
-        self.len = cache_len
-        self.contains = cache_contains
-        self.clear = cache_clear
-
-    def __getitem__(self, key):
-        result = self.get(key, self.sentinel)
-        if result is self.sentinel:
-            raise KeyError()
-        else:
-            return result
-
-    def __setitem__(self, key, value):
-        self.set(key, value)
-
-    def __delitem__(self, key, value):
-        result = self.pop(key, self.sentinel)
-        if result is self.sentinel:
-            raise KeyError()
-
-    def __len__(self):
-        return self.len()
-
-    def __contains__(self, key):
-        return self.contains(key)