mirror of
https://github.com/mongodb/mongo.git
synced 2024-11-30 00:56:44 +01:00
122 lines
3.3 KiB
C++
122 lines
3.3 KiB
C++
// mmap.h
|
|
|
|
/* Copyright 2009 10gen Inc.
|
|
*
|
|
* 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.
|
|
*/
|
|
|
|
#pragma once
|
|
|
|
namespace mongo {
|
|
|
|
/* the administrative-ish stuff here */
|
|
class MongoFile {
|
|
protected:
|
|
virtual void close() = 0;
|
|
virtual void flush(bool sync) = 0;
|
|
void created(); /* subclass must call after create */
|
|
public:
|
|
virtual long length() = 0;
|
|
|
|
enum Options {
|
|
SEQUENTIAL = 1 // hint - e.g. FILE_FLAG_SEQUENTIAL_SCAN on windows
|
|
};
|
|
|
|
virtual ~MongoFile();
|
|
|
|
static int flushAll( bool sync ); // returns n flushed
|
|
static long long totalMappedLength();
|
|
static void closeAllFiles( stringstream &message );
|
|
|
|
/* can be "overriden" if necessary */
|
|
static bool exists(boost::filesystem::path p) {
|
|
return boost::filesystem::exists(p);
|
|
}
|
|
};
|
|
|
|
class MFTemplate : public MongoFile {
|
|
protected:
|
|
virtual void close();
|
|
virtual void flush(bool sync);
|
|
public:
|
|
virtual long length();
|
|
|
|
class Pointer {
|
|
public:
|
|
void* at(int offset, int maxLen);
|
|
bool isNull() const;
|
|
};
|
|
|
|
Pointer map( const char *filename );
|
|
Pointer map(const char *_filename, long &length, int options=0);
|
|
};
|
|
|
|
class MemoryMappedFile : public MongoFile {
|
|
public:
|
|
class Pointer {
|
|
char *_base;
|
|
public:
|
|
Pointer() : _base(0) { }
|
|
Pointer(void *p) : _base((char*) p) { }
|
|
void* at(int offset, int maxLen) { return _base + offset; }
|
|
bool isNull() const { return _base == 0; }
|
|
};
|
|
|
|
MemoryMappedFile();
|
|
~MemoryMappedFile() { close(); }
|
|
void close();
|
|
|
|
// Throws exception if file doesn't exist. (dm may2010: not sure if this is always true?)
|
|
void* map( const char *filename );
|
|
/*Pointer pmap( const char *filename ) {
|
|
void *p = map(filename);
|
|
uassert(13077, "couldn't open/map file", p);
|
|
return Pointer(p);
|
|
}*/
|
|
|
|
/* Creates with length if DNE, otherwise uses existing file length,
|
|
passed length.
|
|
*/
|
|
void* map(const char *filename, long &length, int options = 0 );
|
|
|
|
void flush(bool sync);
|
|
|
|
/*void* viewOfs() {
|
|
return view;
|
|
}*/
|
|
|
|
long length() {
|
|
return len;
|
|
}
|
|
|
|
private:
|
|
static void updateLength( const char *filename, long &length );
|
|
|
|
HANDLE fd;
|
|
HANDLE maphandle;
|
|
void *view;
|
|
long len;
|
|
};
|
|
|
|
void printMemInfo( const char * where );
|
|
|
|
//#define _RAMSTORE
|
|
#if defined(_RAMSTORE)
|
|
#include "ramstore.h"
|
|
typedef RamStoreFile MMF;
|
|
#else
|
|
typedef MemoryMappedFile MMF;
|
|
#endif
|
|
|
|
} // namespace mongo
|