LruCache: avoid copying keys in lookup

Create objects of type KeyedEntry for lookups that only have
a key reference

Bug: 27567036
Change-Id: I5e609a3db63d3b9277ff1547a3cca37dce70251c

1 files changed, 18 insertions, 0 deletions

diff --git a/libutils/tests/LruCache_test.cpp b/libutils/tests/LruCache_test.cpp
index dd95c576d..de440fd7e 100644
--- a/libutils/tests/LruCache_test.cpp
+++ b/libutils/tests/LruCache_test.cpp
@@ -80,6 +80,14 @@ struct KeyWithPointer {
     }
 };
 
+struct KeyFailsOnCopy : public ComplexKey {
+    public:
+    KeyFailsOnCopy(const KeyFailsOnCopy& key) : ComplexKey(key) {
+        ADD_FAILURE();
+    }
+    KeyFailsOnCopy(int key) : ComplexKey(key) { }
+};
+
 } // namespace
 
 
@@ -95,6 +103,10 @@ template<> inline android::hash_t hash_type(const KeyWithPointer& value) {
     return hash_type(*value.ptr);
 }
 
+template<> inline android::hash_t hash_type(const KeyFailsOnCopy& value) {
+    return hash_type<ComplexKey>(value);
+}
+
 class EntryRemovedCallback : public OnEntryRemoved<SimpleKey, StringValue> {
 public:
     EntryRemovedCallback() : callbackCount(0), lastKey(-1), lastValue(NULL) { }
@@ -437,4 +449,10 @@ TEST_F(LruCacheTest, RemoveNonMember) {
     EXPECT_EQ(std::unordered_set<int>({ 4, 5, 6 }), returnedValues);
 }
 
+TEST_F(LruCacheTest, DontCopyKeyInGet) {
+    LruCache<KeyFailsOnCopy, KeyFailsOnCopy> cache(1);
+    // Check that get doesn't copy the key
+    cache.get(KeyFailsOnCopy(0));
+}
+
 }