leveldb/port/port_osx.h
dgrogan@chromium.org 740d8b3d00 Update from upstream @21551990
* Patch LevelDB to build for OSX and iOS
* Fix race condition in memtable iterator deletion.
* Other small fixes.

git-svn-id: https://leveldb.googlecode.com/svn/trunk@29 62dab493-f737-651d-591e-8d6aee1b9529
2011-05-28 00:53:58 +00:00

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2.6 KiB
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// Copyright (c) 2011 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.
//
// See port_example.h for documentation for the following types/functions.
#ifndef STORAGE_LEVELDB_PORT_PORT_OSX_H_
#define STORAGE_LEVELDB_PORT_PORT_OSX_H_
#include <libkern/OSAtomic.h>
#include <machine/endian.h>
#include <pthread.h>
#include <stdint.h>
#include <string>
namespace leveldb {
// The following 4 methods implemented here for the benefit of env_posix.cc.
inline size_t fread_unlocked(void *a, size_t b, size_t c, FILE *d) {
return fread(a, b, c, d);
}
inline size_t fwrite_unlocked(const void *a, size_t b, size_t c, FILE *d) {
return fwrite(a, b, c, d);
}
inline int fflush_unlocked(FILE *f) {
return fflush(f);
}
inline int fdatasync(int fd) {
return fsync(fd);
}
namespace port {
static const bool kLittleEndian = (__DARWIN_BYTE_ORDER == __DARWIN_LITTLE_ENDIAN);
// ------------------ Threading -------------------
// A Mutex represents an exclusive lock.
class Mutex {
public:
Mutex();
~Mutex();
void Lock();
void Unlock();
void AssertHeld() { }
private:
friend class CondVar;
pthread_mutex_t mu_;
// No copying
Mutex(const Mutex&);
void operator=(const Mutex&);
};
class CondVar {
public:
explicit CondVar(Mutex* mu);
~CondVar();
void Wait();
void Signal();
void SignalAll();
private:
pthread_cond_t cv_;
Mutex* mu_;
};
inline void MemoryBarrier() {
#if defined(__GNUC__) && (defined(__i386__) || defined(__x86_64__))
// See http://gcc.gnu.org/ml/gcc/2003-04/msg01180.html for a discussion on
// this idiom. Also see http://en.wikipedia.org/wiki/Memory_ordering.
__asm__ __volatile__("" : : : "memory");
#else
OSMemoryBarrier();
#endif
}
class AtomicPointer {
private:
void* ptr_;
public:
AtomicPointer() { }
explicit AtomicPointer(void* p) : ptr_(p) {}
inline void* Acquire_Load() const {
void* ptr = ptr_;
MemoryBarrier();
return ptr;
}
inline void Release_Store(void* v) {
MemoryBarrier();
ptr_ = v;
}
inline void* NoBarrier_Load() const {
return ptr_;
}
inline void NoBarrier_Store(void* v) {
ptr_ = v;
}
};
inline bool Snappy_Compress(const char* input, size_t input_length,
std::string* output) {
return false;
}
inline bool Snappy_Uncompress(const char* input_data, size_t input_length,
std::string* output) {
return false;
}
inline bool GetHeapProfile(void (*func)(void*, const char*, int), void* arg) {
return false;
}
}
}
#endif // STORAGE_LEVELDB_PORT_PORT_OSX_H_