citra/src/core/file_sys/ivfc_archive.h

122 lines
4.3 KiB
C++

// Copyright 2014 Citra Emulator Project
// Licensed under GPLv2 or any later version
// Refer to the license.txt file included.
#pragma once
#include <cstddef>
#include <memory>
#include <string>
#include "common/common_types.h"
#include "common/file_util.h"
#include "core/file_sys/archive_backend.h"
#include "core/file_sys/directory_backend.h"
#include "core/file_sys/file_backend.h"
#include "core/hle/result.h"
////////////////////////////////////////////////////////////////////////////////////////////////////
// FileSys namespace
namespace FileSys {
class IVFCDelayGenerator : public DelayGenerator {
u64 GetReadDelayNs(size_t length) override {
// This is the delay measured for a romfs read.
// For now we will take that as a default
static constexpr u64 slope(94);
static constexpr u64 offset(582778);
static constexpr u64 minimum(663124);
u64 IPCDelayNanoseconds = std::max<u64>(static_cast<u64>(length) * slope + offset, minimum);
return IPCDelayNanoseconds;
}
};
class RomFSDelayGenerator : public DelayGenerator {
public:
u64 GetReadDelayNs(size_t length) override {
// The delay was measured on O3DS and O2DS with
// https://gist.github.com/B3n30/ac40eac20603f519ff106107f4ac9182
// from the results the average of each length was taken.
static constexpr u64 slope(94);
static constexpr u64 offset(582778);
static constexpr u64 minimum(663124);
u64 IPCDelayNanoseconds = std::max<u64>(static_cast<u64>(length) * slope + offset, minimum);
return IPCDelayNanoseconds;
}
};
class ExeFSDelayGenerator : public DelayGenerator {
public:
u64 GetReadDelayNs(size_t length) override {
// The delay was measured on O3DS and O2DS with
// https://gist.github.com/B3n30/ac40eac20603f519ff106107f4ac9182
// from the results the average of each length was taken.
static constexpr u64 slope(94);
static constexpr u64 offset(582778);
static constexpr u64 minimum(663124);
u64 IPCDelayNanoseconds = std::max<u64>(static_cast<u64>(length) * slope + offset, minimum);
return IPCDelayNanoseconds;
}
};
/**
* Helper which implements an interface to deal with IVFC images used in some archives
* This should be subclassed by concrete archive types, which will provide the
* input data (load the raw IVFC archive) and override any required methods
*/
class IVFCArchive : public ArchiveBackend {
public:
IVFCArchive(std::shared_ptr<FileUtil::IOFile> file, u64 offset, u64 size);
std::string GetName() const override;
ResultVal<std::unique_ptr<FileBackend>> OpenFile(const Path& path,
const Mode& mode) const override;
ResultCode DeleteFile(const Path& path) const override;
ResultCode RenameFile(const Path& src_path, const Path& dest_path) const override;
ResultCode DeleteDirectory(const Path& path) const override;
ResultCode DeleteDirectoryRecursively(const Path& path) const override;
ResultCode CreateFile(const Path& path, u64 size) const override;
ResultCode CreateDirectory(const Path& path) const override;
ResultCode RenameDirectory(const Path& src_path, const Path& dest_path) const override;
ResultVal<std::unique_ptr<DirectoryBackend>> OpenDirectory(const Path& path) const override;
u64 GetFreeBytes() const override;
protected:
std::shared_ptr<FileUtil::IOFile> romfs_file;
u64 data_offset;
u64 data_size;
};
class IVFCFile : public FileBackend {
public:
IVFCFile(std::shared_ptr<FileUtil::IOFile> file, u64 offset, u64 size,
std::unique_ptr<DelayGenerator> delay_generator_);
ResultVal<size_t> Read(u64 offset, size_t length, u8* buffer) const override;
ResultVal<size_t> Write(u64 offset, size_t length, bool flush, const u8* buffer) override;
u64 GetSize() const override;
bool SetSize(u64 size) const override;
bool Close() const override {
return false;
}
void Flush() const override {}
private:
std::shared_ptr<FileUtil::IOFile> romfs_file;
u64 data_offset;
u64 data_size;
};
class IVFCDirectory : public DirectoryBackend {
public:
u32 Read(const u32 count, Entry* entries) override {
return 0;
}
bool Close() const override {
return false;
}
};
} // namespace FileSys