Atmosphere/libraries/libstratosphere/source/ncm/ncm_placeholder_accessor.cpp
2020-03-08 01:45:12 -08:00

257 lines
9.9 KiB
C++

/*
* Copyright (c) 2019-2020 Adubbz, 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/>.
*/
#include <stratosphere.hpp>
#include "ncm_placeholder_accessor.hpp"
#include "ncm_fs_utils.hpp"
namespace ams::ncm {
namespace {
constexpr inline const char * const BasePlaceHolderDirectory = "/placehld";
constexpr inline const char * const PlaceHolderExtension = ".nca";
constexpr inline size_t PlaceHolderExtensionLength = 4;
constexpr inline size_t PlaceHolderFileNameLengthWithoutExtension = 2 * sizeof(PlaceHolderId);
constexpr inline size_t PlaceHolderFileNameLength = PlaceHolderFileNameLengthWithoutExtension + PlaceHolderExtensionLength;
void MakeBasePlaceHolderDirectoryPath(PathString *out, const char *root_path) {
out->SetFormat("%s%s", root_path, BasePlaceHolderDirectory);
}
void MakePlaceHolderFilePath(PathString *out, PlaceHolderId id, MakePlaceHolderPathFunction func, const char *root_path) {
PathString path;
MakeBasePlaceHolderDirectoryPath(std::addressof(path), root_path);
func(out, id, path);
}
ALWAYS_INLINE Result ConvertNotFoundResult(Result r) {
R_TRY_CATCH(r) {
R_CONVERT(ams::fs::ResultPathNotFound, ncm::ResultPlaceHolderNotFound())
} R_END_TRY_CATCH;
return ResultSuccess();
}
}
void PlaceHolderAccessor::MakePath(PathString *out_placeholder_path, PlaceHolderId placeholder_id) const {
MakePlaceHolderFilePath(out_placeholder_path, placeholder_id, this->make_placeholder_path_func, *this->root_path);
}
void PlaceHolderAccessor::MakeBaseDirectoryPath(PathString *out, const char *root_path) {
MakeBasePlaceHolderDirectoryPath(out, root_path);
}
Result PlaceHolderAccessor::EnsurePlaceHolderDirectory(PlaceHolderId placeholder_id) {
PathString path;
this->MakePath(std::addressof(path), placeholder_id);
return fs::EnsureParentDirectoryRecursively(path);
}
Result PlaceHolderAccessor::GetPlaceHolderIdFromFileName(PlaceHolderId *out, const char *name) {
/* Ensure placeholder name is valid. */
R_UNLESS(strnlen(name, PlaceHolderFileNameLength) == PlaceHolderFileNameLength, ncm::ResultInvalidPlaceHolderFile());
R_UNLESS(strncmp(name + PlaceHolderFileNameLengthWithoutExtension, PlaceHolderExtension, PlaceHolderExtensionLength) == 0, ncm::ResultInvalidPlaceHolderFile());
/* Convert each character pair to a byte until we reach the end. */
PlaceHolderId placeholder_id = {};
for (size_t i = 0; i < sizeof(placeholder_id); i++) {
char tmp[3];
strlcpy(tmp, name + i * 2, sizeof(tmp));
char *err = nullptr;
reinterpret_cast<u8 *>(std::addressof(placeholder_id))[i] = static_cast<u8>(std::strtoul(tmp, std::addressof(err), 16));
R_UNLESS(*err == '\x00', ncm::ResultInvalidPlaceHolderFile());
}
*out = placeholder_id;
return ResultSuccess();
}
Result PlaceHolderAccessor::Open(fs::FileHandle *out_handle, PlaceHolderId placeholder_id) {
/* Try to load from the cache. */
R_SUCCEED_IF(this->LoadFromCache(out_handle, placeholder_id));
/* Make the path of the placeholder. */
PathString placeholder_path;
this->MakePath(std::addressof(placeholder_path), placeholder_id);
/* Open the placeholder file. */
return fs::OpenFile(out_handle, placeholder_path, fs::OpenMode_Write);
}
bool PlaceHolderAccessor::LoadFromCache(fs::FileHandle *out_handle, PlaceHolderId placeholder_id) {
std::scoped_lock lk(this->cache_mutex);
/* Attempt to find an entry in the cache. */
CacheEntry *entry = this->FindInCache(placeholder_id);
if (!entry) {
return false;
}
/* No cached entry found. */
entry->id = InvalidPlaceHolderId;
*out_handle = entry->handle;
return true;
}
void PlaceHolderAccessor::StoreToCache(PlaceHolderId placeholder_id, fs::FileHandle handle) {
std::scoped_lock lk(this->cache_mutex);
/* Store placeholder id and file handle to a free entry. */
CacheEntry *entry = this->GetFreeEntry();
entry->id = placeholder_id;
entry->handle = handle;
entry->counter = this->cur_counter++;
}
void PlaceHolderAccessor::Invalidate(CacheEntry *entry) {
/* Flush and close the cached entry's file. */
if (entry != nullptr) {
fs::FlushFile(entry->handle);
fs::CloseFile(entry->handle);
entry->id = InvalidPlaceHolderId;
}
}
PlaceHolderAccessor::CacheEntry *PlaceHolderAccessor::FindInCache(PlaceHolderId placeholder_id) {
/* Ensure placeholder id is valid. */
if (placeholder_id == InvalidPlaceHolderId) {
return nullptr;
}
/* Attempt to find a cache entry with the same placeholder id. */
for (size_t i = 0; i < MaxCacheEntries; i++) {
if (placeholder_id == this->caches[i].id) {
return &this->caches[i];
}
}
return nullptr;
}
PlaceHolderAccessor::CacheEntry *PlaceHolderAccessor::GetFreeEntry() {
/* Try to find an already free entry. */
for (size_t i = 0; i < MaxCacheEntries; i++) {
if (this->caches[i].id == InvalidPlaceHolderId) {
return std::addressof(this->caches[i]);
}
}
/* Get the oldest entry. */
CacheEntry *entry = std::addressof(this->caches[0]);
for (size_t i = 1; i < MaxCacheEntries; i++) {
if (entry->counter < this->caches[i].counter) {
entry = std::addressof(this->caches[i]);
}
}
this->Invalidate(entry);
return entry;
}
void PlaceHolderAccessor::GetPath(PathString *placeholder_path, PlaceHolderId placeholder_id) {
{
std::scoped_lock lock(this->cache_mutex);
this->Invalidate(this->FindInCache(placeholder_id));
}
this->MakePath(placeholder_path, placeholder_id);
}
Result PlaceHolderAccessor::CreatePlaceHolderFile(PlaceHolderId placeholder_id, s64 size) {
/* Ensure the destination directory exists. */
R_TRY(this->EnsurePlaceHolderDirectory(placeholder_id));
/* Get the placeholder path. */
PathString placeholder_path;
this->GetPath(std::addressof(placeholder_path), placeholder_id);
/* Create the placeholder file. */
R_TRY_CATCH(fs::CreateFile(placeholder_path, size, fs::CreateOption_BigFile)) {
R_CONVERT(fs::ResultPathAlreadyExists, ncm::ResultPlaceHolderAlreadyExists())
} R_END_TRY_CATCH;
return ResultSuccess();
}
Result PlaceHolderAccessor::DeletePlaceHolderFile(PlaceHolderId placeholder_id) {
/* Get the placeholder path. */
PathString placeholder_path;
this->GetPath(std::addressof(placeholder_path), placeholder_id);
/* Delete the placeholder file. */
R_TRY_CATCH(fs::DeleteFile(placeholder_path)) {
R_CONVERT(fs::ResultPathNotFound, ncm::ResultPlaceHolderNotFound())
} R_END_TRY_CATCH;
return ResultSuccess();
}
Result PlaceHolderAccessor::WritePlaceHolderFile(PlaceHolderId placeholder_id, s64 offset, const void *buffer, size_t size) {
/* Open the placeholder file. */
fs::FileHandle file;
R_TRY_CATCH(this->Open(std::addressof(file), placeholder_id)) {
R_CONVERT(fs::ResultPathNotFound, ncm::ResultPlaceHolderNotFound())
} R_END_TRY_CATCH;
/* Store opened files to the cache regardless of write failures. */
ON_SCOPE_EXIT { this->StoreToCache(placeholder_id, file); };
/* Write data to the placeholder file. */
return fs::WriteFile(file, offset, buffer, size, this->delay_flush ? fs::WriteOption::Flush : fs::WriteOption::None);
}
Result PlaceHolderAccessor::SetPlaceHolderFileSize(PlaceHolderId placeholder_id, s64 size) {
/* Open the placeholder file. */
fs::FileHandle file;
R_TRY_CATCH(this->Open(std::addressof(file), placeholder_id)) {
R_CONVERT(fs::ResultPathNotFound, ncm::ResultPlaceHolderNotFound())
} R_END_TRY_CATCH;
/* Close the file on exit. */
ON_SCOPE_EXIT { fs::CloseFile(file); };
/* Set the size of the placeholder file. */
return fs::SetFileSize(file, size);
}
Result PlaceHolderAccessor::TryGetPlaceHolderFileSize(bool *found_in_cache, s64 *out_size, PlaceHolderId placeholder_id) {
/* Attempt to find the placeholder in the cache. */
fs::FileHandle handle;
auto found = this->LoadFromCache(std::addressof(handle), placeholder_id);
if (found) {
/* Renew the entry in the cache. */
this->StoreToCache(placeholder_id, handle);
R_TRY(fs::GetFileSize(out_size, handle));
*found_in_cache = true;
} else {
*found_in_cache = false;
}
return ResultSuccess();
}
void PlaceHolderAccessor::InvalidateAll() {
/* Invalidate all cache entries. */
for (auto &entry : this->caches) {
if (entry.id != InvalidPlaceHolderId) {
this->Invalidate(std::addressof(entry));
}
}
}
}