44 lines
905 B
C++
44 lines
905 B
C++
#ifndef MEMORYMAPPEDFILE_H_
|
|
#define MEMORYMAPPEDFILE_H_
|
|
|
|
#include <stddef.h>
|
|
|
|
|
|
class MemoryMappedFile {
|
|
void *pv;
|
|
size_t sz;
|
|
|
|
MemoryMappedFile(const MemoryMappedFile&) = delete;
|
|
MemoryMappedFile& operator=(const MemoryMappedFile) = delete;
|
|
|
|
public:
|
|
MemoryMappedFile() : pv(0), sz(0) {}
|
|
MemoryMappedFile(const char *filename, bool for_write=false)
|
|
: pv(0), sz(0)
|
|
{
|
|
open(filename,for_write);
|
|
}
|
|
~MemoryMappedFile() { close(); }
|
|
|
|
bool open(const char *filename, bool for_write=false);
|
|
void close();
|
|
|
|
bool is_open() const { return pv!=0; }
|
|
|
|
char *start() { return (char*)pv; }
|
|
const char *start() const { return (const char*)pv; }
|
|
size_t size() const { return sz; }
|
|
|
|
void advise_normal() const;
|
|
void advise_random() const;
|
|
void advice_sequential() const;
|
|
void advise_willneed() const;
|
|
void advise_dontneed() const;
|
|
|
|
private:
|
|
void advise(int advice) const;
|
|
};
|
|
|
|
|
|
#endif
|