作者: 谢瑞阳 10225101483 徐翔宇 10225101535
Nelze vybrat více než 25 témat Téma musí začínat písmenem nebo číslem, může obsahovat pomlčky („-“) a může být dlouhé až 35 znaků.
 
 

129 řádky
2.9 KiB

// 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_POSIX_H_
#define STORAGE_LEVELDB_PORT_PORT_POSIX_H_
#if defined(OS_MACOSX)
#include <machine/endian.h>
#elif defined(OS_SOLARIS)
#include <sys/isa_defs.h>
#ifdef _LITTLE_ENDIAN
#define LITTLE_ENDIAN
#else
#define BIG_ENDIAN
#endif
#elif defined(OS_FREEBSD) || defined(OS_OPENBSD) || defined(OS_NETBSD) ||\
defined(OS_DRAGONFLYBSD)
#include <sys/types.h>
#include <sys/endian.h>
#else
#include <endian.h>
#endif
#include <pthread.h>
#ifdef SNAPPY
#include <snappy.h>
#endif
#include <stdint.h>
#include <string>
#include "port/atomic_pointer.h"
#ifdef LITTLE_ENDIAN
#define IS_LITTLE_ENDIAN true
#else
#define IS_LITTLE_ENDIAN (__BYTE_ORDER == __LITTLE_ENDIAN)
#endif
#if defined(OS_MACOSX) || defined(OS_SOLARIS) || defined(OS_FREEBSD) ||\
defined(OS_NETBSD) || defined(OS_OPENBSD) || defined(OS_DRAGONFLYBSD)
// Use fread/fwrite/fflush on platforms without _unlocked variants
#define fread_unlocked fread
#define fwrite_unlocked fwrite
#define fflush_unlocked fflush
#endif
#if defined(OS_MACOSX) || defined(OS_FREEBSD) ||\
defined(OS_OPENBSD) || defined(OS_DRAGONFLYBSD)
// Use fsync() on platforms without fdatasync()
#define fdatasync fsync
#endif
namespace leveldb {
namespace port {
static const bool kLittleEndian = IS_LITTLE_ENDIAN;
class CondVar;
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 bool Snappy_Compress(const char* input, size_t length,
::std::string* output) {
#ifdef SNAPPY
output->resize(snappy::MaxCompressedLength(length));
size_t outlen;
snappy::RawCompress(input, length, &(*output)[0], &outlen);
output->resize(outlen);
return true;
#endif
return false;
}
inline bool Snappy_GetUncompressedLength(const char* input, size_t length,
size_t* result) {
#ifdef SNAPPY
return snappy::GetUncompressedLength(input, length, result);
#else
return false;
#endif
}
inline bool Snappy_Uncompress(const char* input, size_t length,
char* output) {
#ifdef SNAPPY
return snappy::RawUncompress(input, length, output);
#else
return false;
#endif
}
inline bool GetHeapProfile(void (*func)(void*, const char*, int), void* arg) {
return false;
}
} // namespace port
} // namespace leveldb
#endif // STORAGE_LEVELDB_PORT_PORT_POSIX_H_