Atmosphere/libraries/libstratosphere/include/stratosphere/fs/fs_substorage.hpp

148 lines
6.7 KiB
C++

/*
* Copyright (c) Atmosphère-NX
*
* This program is free software; you can redistribute it and/or modify it
* under the terms and conditions of the GNU General Public License,
* version 2, as published by the Free Software Foundation.
*
* This program is distributed in the hope it will be useful, but WITHOUT
* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
* more details.
*
* You should have received a copy of the GNU General Public License
* along with this program. If not, see <http://www.gnu.org/licenses/>.
*/
#pragma once
#include <stratosphere/fs/impl/fs_newable.hpp>
#include <stratosphere/fs/fs_istorage.hpp>
namespace ams::fs {
class SubStorage : public ::ams::fs::IStorage, public ::ams::fs::impl::Newable {
private:
std::shared_ptr<IStorage> m_shared_base_storage;
fs::IStorage *m_base_storage;
s64 m_offset;
s64 m_size;
bool m_resizable;
private:
constexpr bool IsValid() const {
return m_base_storage != nullptr;
}
public:
SubStorage() : m_shared_base_storage(), m_base_storage(nullptr), m_offset(0), m_size(0), m_resizable(false) { /* ... */ }
SubStorage(const SubStorage &rhs) : m_shared_base_storage(rhs.m_shared_base_storage), m_base_storage(rhs.m_base_storage), m_offset(rhs.m_offset), m_size(rhs.m_size), m_resizable(rhs.m_resizable) { /* ... */}
SubStorage &operator=(const SubStorage &rhs) {
if (this != std::addressof(rhs)) {
m_shared_base_storage = rhs.m_shared_base_storage;
m_base_storage = rhs.m_base_storage;
m_offset = rhs.m_offset;
m_size = rhs.m_size;
m_resizable = rhs.m_resizable;
}
return *this;
}
SubStorage(IStorage *storage, s64 o, s64 sz) : m_shared_base_storage(), m_base_storage(storage), m_offset(o), m_size(sz), m_resizable(false) {
AMS_ABORT_UNLESS(this->IsValid());
AMS_ABORT_UNLESS(m_offset >= 0);
AMS_ABORT_UNLESS(m_size >= 0);
}
SubStorage(std::shared_ptr<IStorage> storage, s64 o, s64 sz) : m_shared_base_storage(storage), m_base_storage(storage.get()), m_offset(o), m_size(sz), m_resizable(false) {
AMS_ABORT_UNLESS(this->IsValid());
AMS_ABORT_UNLESS(m_offset >= 0);
AMS_ABORT_UNLESS(m_size >= 0);
}
SubStorage(SubStorage *sub, s64 o, s64 sz) : m_shared_base_storage(sub->m_shared_base_storage), m_base_storage(sub->m_base_storage), m_offset(o + sub->m_offset), m_size(sz), m_resizable(false) {
AMS_ABORT_UNLESS(this->IsValid());
AMS_ABORT_UNLESS(m_offset >= 0);
AMS_ABORT_UNLESS(m_size >= 0);
AMS_ABORT_UNLESS(sub->m_size >= o + sz);
}
ALWAYS_INLINE ::ams::fs::IStorage *operator->() {
return this;
}
public:
void SetResizable(bool rsz) {
m_resizable = rsz;
}
public:
virtual Result Read(s64 offset, void *buffer, size_t size) override {
/* Ensure we're initialized. */
R_UNLESS(this->IsValid(), fs::ResultNotInitialized());
/* Succeed immediately on zero-sized operation. */
R_SUCCEED_IF(size == 0);
/* Validate arguments and read. */
R_UNLESS(buffer != nullptr, fs::ResultNullptrArgument());
R_UNLESS(IStorage::CheckAccessRange(offset, size, m_size), fs::ResultOutOfRange());
return m_base_storage->Read(m_offset + offset, buffer, size);
}
virtual Result Write(s64 offset, const void *buffer, size_t size) override{
/* Ensure we're initialized. */
R_UNLESS(this->IsValid(), fs::ResultNotInitialized());
/* Succeed immediately on zero-sized operation. */
R_SUCCEED_IF(size == 0);
/* Validate arguments and write. */
R_UNLESS(buffer != nullptr, fs::ResultNullptrArgument());
R_UNLESS(IStorage::CheckAccessRange(offset, size, m_size), fs::ResultOutOfRange());
return m_base_storage->Write(m_offset + offset, buffer, size);
}
virtual Result Flush() override {
R_UNLESS(this->IsValid(), fs::ResultNotInitialized());
return m_base_storage->Flush();
}
virtual Result SetSize(s64 size) override {
/* Ensure we're initialized and validate arguments. */
R_UNLESS(this->IsValid(), fs::ResultNotInitialized());
R_UNLESS(m_resizable, fs::ResultUnsupportedOperationInSubStorageA());
R_UNLESS(IStorage::CheckOffsetAndSize(m_offset, size), fs::ResultInvalidSize());
/* Ensure that we're allowed to set size. */
s64 cur_size;
R_TRY(m_base_storage->GetSize(std::addressof(cur_size)));
R_UNLESS(cur_size == m_offset + m_size, fs::ResultUnsupportedOperationInSubStorageB());
/* Set the size. */
R_TRY(m_base_storage->SetSize(m_offset + size));
m_size = size;
return ResultSuccess();
}
virtual Result GetSize(s64 *out) override {
/* Ensure we're initialized. */
R_UNLESS(this->IsValid(), fs::ResultNotInitialized());
*out = m_size;
return ResultSuccess();
}
virtual Result OperateRange(void *dst, size_t dst_size, OperationId op_id, s64 offset, s64 size, const void *src, size_t src_size) override {
/* Ensure we're initialized. */
R_UNLESS(this->IsValid(), fs::ResultNotInitialized());
/* Succeed immediately on zero-sized operation. */
R_SUCCEED_IF(size == 0);
/* Validate arguments and operate. */
R_UNLESS(IStorage::CheckOffsetAndSize(offset, size), fs::ResultOutOfRange());
return m_base_storage->OperateRange(dst, dst_size, op_id, m_offset + offset, size, src, src_size);
}
using IStorage::OperateRange;
};
}