Combine leaks with same stacktrace

[android-x86/system-core.git] / libmemunreachable / Leak.h

diff --git a/libmemunreachable/Leak.h b/libmemunreachable/Leak.h
new file mode 100644 (file)
index 0000000..eaeeea7
--- /dev/null
+++ b/libmemunreachable/Leak.h
@@ -0,0 +1,57 @@
+/*
+ * Copyright (C) 2016 The Android Open Source Project
+ *
+ * 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.
+ */
+
+#ifndef LIBMEMUNREACHABLE_LEAK_H_
+#define LIBMEMUNREACHABLE_LEAK_H_
+
+#include <functional>
+#include <vector>
+
+#include "memunreachable/memunreachable.h"
+
+// Custom std::hash specialization so that Leak::Backtrace can be used
+// as a key in std::unordered_map.
+namespace std {
+
+template<>
+struct hash<Leak::Backtrace> {
+  std::size_t operator()(const Leak::Backtrace& key) const {
+    std::size_t seed = 0;
+
+    hash_combine(seed, key.num_frames);
+    for (size_t i = 0; i < key.num_frames; i++) {
+      hash_combine(seed, key.frames[i]);
+    }
+
+    return seed;
+  }
+
+ private:
+  template<typename T>
+  inline void hash_combine(std::size_t& seed, const T& v) const {
+    std::hash<T> hasher;
+    seed ^= hasher(v) + 0x9e3779b9 + (seed << 6) + (seed >> 2);
+  }
+};
+
+}  // namespace std
+
+static bool operator==(const Leak::Backtrace& lhs, const Leak::Backtrace& rhs) {
+  return (lhs.num_frames == rhs.num_frames) &&
+      memcmp(lhs.frames, rhs.frames, lhs.num_frames * sizeof(lhs.frames[0])) == 0;
+}
+
+#endif