aboutsummaryrefslogtreecommitdiff
path: root/src/leveldb/port/port_stdcxx.h
diff options
context:
space:
mode:
Diffstat (limited to 'src/leveldb/port/port_stdcxx.h')
-rw-r--r--src/leveldb/port/port_stdcxx.h153
1 files changed, 153 insertions, 0 deletions
diff --git a/src/leveldb/port/port_stdcxx.h b/src/leveldb/port/port_stdcxx.h
new file mode 100644
index 0000000000..e9cb0e53af
--- /dev/null
+++ b/src/leveldb/port/port_stdcxx.h
@@ -0,0 +1,153 @@
+// Copyright (c) 2018 The LevelDB Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file. See the AUTHORS file for names of contributors.
+
+#ifndef STORAGE_LEVELDB_PORT_PORT_STDCXX_H_
+#define STORAGE_LEVELDB_PORT_PORT_STDCXX_H_
+
+// port/port_config.h availability is automatically detected via __has_include
+// in newer compilers. If LEVELDB_HAS_PORT_CONFIG_H is defined, it overrides the
+// configuration detection.
+#if defined(LEVELDB_HAS_PORT_CONFIG_H)
+
+#if LEVELDB_HAS_PORT_CONFIG_H
+#include "port/port_config.h"
+#endif // LEVELDB_HAS_PORT_CONFIG_H
+
+#elif defined(__has_include)
+
+#if __has_include("port/port_config.h")
+#include "port/port_config.h"
+#endif // __has_include("port/port_config.h")
+
+#endif // defined(LEVELDB_HAS_PORT_CONFIG_H)
+
+#if HAVE_CRC32C
+#include <crc32c/crc32c.h>
+#endif // HAVE_CRC32C
+#if HAVE_SNAPPY
+#include <snappy.h>
+#endif // HAVE_SNAPPY
+
+#include <cassert>
+#include <condition_variable> // NOLINT
+#include <cstddef>
+#include <cstdint>
+#include <mutex> // NOLINT
+#include <string>
+
+#include "port/thread_annotations.h"
+
+namespace leveldb {
+namespace port {
+
+static const bool kLittleEndian = !LEVELDB_IS_BIG_ENDIAN;
+
+class CondVar;
+
+// Thinly wraps std::mutex.
+class LOCKABLE Mutex {
+ public:
+ Mutex() = default;
+ ~Mutex() = default;
+
+ Mutex(const Mutex&) = delete;
+ Mutex& operator=(const Mutex&) = delete;
+
+ void Lock() EXCLUSIVE_LOCK_FUNCTION() { mu_.lock(); }
+ void Unlock() UNLOCK_FUNCTION() { mu_.unlock(); }
+ void AssertHeld() ASSERT_EXCLUSIVE_LOCK() {}
+
+ private:
+ friend class CondVar;
+ std::mutex mu_;
+};
+
+// Thinly wraps std::condition_variable.
+class CondVar {
+ public:
+ explicit CondVar(Mutex* mu) : mu_(mu) { assert(mu != nullptr); }
+ ~CondVar() = default;
+
+ CondVar(const CondVar&) = delete;
+ CondVar& operator=(const CondVar&) = delete;
+
+ void Wait() {
+ std::unique_lock<std::mutex> lock(mu_->mu_, std::adopt_lock);
+ cv_.wait(lock);
+ lock.release();
+ }
+ void Signal() { cv_.notify_one(); }
+ void SignalAll() { cv_.notify_all(); }
+
+ private:
+ std::condition_variable cv_;
+ Mutex* const mu_;
+};
+
+inline bool Snappy_Compress(const char* input, size_t length,
+ std::string* output) {
+#if HAVE_SNAPPY
+ output->resize(snappy::MaxCompressedLength(length));
+ size_t outlen;
+ snappy::RawCompress(input, length, &(*output)[0], &outlen);
+ output->resize(outlen);
+ return true;
+#else
+ // Silence compiler warnings about unused arguments.
+ (void)input;
+ (void)length;
+ (void)output;
+#endif // HAVE_SNAPPY
+
+ return false;
+}
+
+inline bool Snappy_GetUncompressedLength(const char* input, size_t length,
+ size_t* result) {
+#if HAVE_SNAPPY
+ return snappy::GetUncompressedLength(input, length, result);
+#else
+ // Silence compiler warnings about unused arguments.
+ (void)input;
+ (void)length;
+ (void)result;
+ return false;
+#endif // HAVE_SNAPPY
+}
+
+inline bool Snappy_Uncompress(const char* input, size_t length, char* output) {
+#if HAVE_SNAPPY
+ return snappy::RawUncompress(input, length, output);
+#else
+ // Silence compiler warnings about unused arguments.
+ (void)input;
+ (void)length;
+ (void)output;
+ return false;
+#endif // HAVE_SNAPPY
+}
+
+inline bool GetHeapProfile(void (*func)(void*, const char*, int), void* arg) {
+ // Silence compiler warnings about unused arguments.
+ (void)func;
+ (void)arg;
+ return false;
+}
+
+inline uint32_t AcceleratedCRC32C(uint32_t crc, const char* buf, size_t size) {
+#if HAVE_CRC32C
+ return ::crc32c::Extend(crc, reinterpret_cast<const uint8_t*>(buf), size);
+#else
+ // Silence compiler warnings about unused arguments.
+ (void)crc;
+ (void)buf;
+ (void)size;
+ return 0;
+#endif // HAVE_CRC32C
+}
+
+} // namespace port
+} // namespace leveldb
+
+#endif // STORAGE_LEVELDB_PORT_PORT_STDCXX_H_