Atmosphere/stratosphere/ams_mitm/source/fs_mitm/fsmitm_romfs.cpp

506 lines
24 KiB
C++

/*
* Copyright (c) 2018-2020 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 "../amsmitm_fs_utils.hpp"
#include "fsmitm_romfs.hpp"
namespace ams::mitm::fs {
using namespace ams::fs;
namespace romfs {
namespace {
constexpr u32 EmptyEntry = 0xFFFFFFFF;
constexpr size_t FilePartitionOffset = 0x200;
struct Header {
s64 header_size;
s64 dir_hash_table_ofs;
s64 dir_hash_table_size;
s64 dir_table_ofs;
s64 dir_table_size;
s64 file_hash_table_ofs;
s64 file_hash_table_size;
s64 file_table_ofs;
s64 file_table_size;
s64 file_partition_ofs;
};
static_assert(std::is_pod<Header>::value && sizeof(Header) == 0x50);
struct DirectoryEntry {
u32 parent;
u32 sibling;
u32 child;
u32 file;
u32 hash;
u32 name_size;
char name[];
};
static_assert(std::is_pod<DirectoryEntry>::value && sizeof(DirectoryEntry) == 0x18);
struct FileEntry {
u32 parent;
u32 sibling;
s64 offset;
s64 size;
u32 hash;
u32 name_size;
char name[];
};
static_assert(std::is_pod<FileEntry>::value && sizeof(FileEntry) == 0x20);
constexpr inline DirectoryEntry *GetDirectoryEntry(void *dir_table, u32 offset) {
return reinterpret_cast<DirectoryEntry *>(reinterpret_cast<uintptr_t>(dir_table) + offset);
}
constexpr inline FileEntry *GetFileEntry(void *file_table, u32 offset) {
return reinterpret_cast<FileEntry *>(reinterpret_cast<uintptr_t>(file_table) + offset);
}
constexpr inline const DirectoryEntry *GetDirectoryEntry(const void *dir_table, u32 offset) {
return reinterpret_cast<const DirectoryEntry *>(reinterpret_cast<uintptr_t>(dir_table) + offset);
}
constexpr inline const FileEntry *GetFileEntry(const void *file_table, u32 offset) {
return reinterpret_cast<const FileEntry *>(reinterpret_cast<uintptr_t>(file_table) + offset);
}
constexpr inline u32 CalculatePathHash(u32 parent, const char *_path, u32 start, size_t path_len) {
const unsigned char *path = reinterpret_cast<const unsigned char *>(_path);
u32 hash = parent ^ 123456789;
for (size_t i = 0; i < path_len; i++) {
hash = (hash >> 5) | (hash << 27);
hash ^= path[start + i];
}
return hash;
}
constexpr inline size_t GetHashTableSize(size_t num_entries) {
if (num_entries < 3) {
return 3;
} else if (num_entries < 19) {
return num_entries | 1;
} else {
size_t count = num_entries;
while ((count % 2 == 0) ||
(count % 3 == 0) ||
(count % 5 == 0) ||
(count % 7 == 0) ||
(count % 11 == 0) ||
(count % 13 == 0) ||
(count % 17 == 0))
{
count++;
}
return count;
}
}
os::Mutex g_fs_romfs_path_lock;
char g_fs_romfs_path_buffer[fs::EntryNameLengthMax + 1];
__attribute__((noinline)) void OpenFileSystemRomfsDirectory(FsDir *out, ncm::ProgramId program_id, BuildDirectoryContext *parent, fs::OpenDirectoryMode mode, FsFileSystem *fs) {
std::scoped_lock lk(g_fs_romfs_path_lock);
parent->GetPath(g_fs_romfs_path_buffer);
R_ASSERT(mitm::fs::OpenAtmosphereRomfsDirectory(out, program_id, g_fs_romfs_path_buffer, mode, fs));
}
}
Builder::Builder(ncm::ProgramId pr_id) : program_id(pr_id), num_dirs(0), num_files(0), dir_table_size(0), file_table_size(0), dir_hash_table_size(0), file_hash_table_size(0), file_partition_size(0) {
auto res = this->directories.emplace(std::make_unique<BuildDirectoryContext>(BuildDirectoryContext::RootTag{}));
AMS_ASSERT(res.second);
this->root = res.first->get();
this->num_dirs = 1;
this->dir_table_size = 0x18;
}
void Builder::AddDirectory(BuildDirectoryContext **out, BuildDirectoryContext *parent_ctx, std::unique_ptr<BuildDirectoryContext> child_ctx) {
/* Set parent context member. */
child_ctx->parent = parent_ctx;
/* Check if the directory already exists. */
auto existing = this->directories.find(child_ctx);
if (existing != this->directories.end()) {
*out = existing->get();
return;
}
/* Add a new directory. */
this->num_dirs++;
this->dir_table_size += sizeof(DirectoryEntry) + util::AlignUp(child_ctx->path_len, 4);
*out = child_ctx.get();
this->directories.emplace(std::move(child_ctx));
}
void Builder::AddFile(BuildDirectoryContext *parent_ctx, std::unique_ptr<BuildFileContext> file_ctx) {
/* Set parent context member. */
file_ctx->parent = parent_ctx;
/* Check if the file already exists. */
if (this->files.find(file_ctx) != this->files.end()) {
return;
}
/* Add a new file. */
this->num_files++;
this->file_table_size += sizeof(FileEntry) + util::AlignUp(file_ctx->path_len, 4);
this->files.emplace(std::move(file_ctx));
}
void Builder::VisitDirectory(FsFileSystem *fs, BuildDirectoryContext *parent) {
FsDir dir;
/* Get number of child directories. */
s64 num_child_dirs = 0;
{
OpenFileSystemRomfsDirectory(&dir, this->program_id, parent, OpenDirectoryMode_Directory, fs);
ON_SCOPE_EXIT { fsDirClose(&dir); };
R_ASSERT(fsDirGetEntryCount(&dir, &num_child_dirs));
}
AMS_ASSERT(num_child_dirs >= 0);
{
BuildDirectoryContext **child_dirs = reinterpret_cast<BuildDirectoryContext **>(std::malloc(sizeof(BuildDirectoryContext *) * num_child_dirs));
ON_SCOPE_EXIT { std::free(child_dirs); };
AMS_ASSERT(child_dirs != nullptr);
s64 cur_child_dir_ind = 0;
{
OpenFileSystemRomfsDirectory(&dir, this->program_id, parent, OpenDirectoryMode_All, fs);
ON_SCOPE_EXIT { fsDirClose(&dir); };
s64 read_entries = 0;
while (true) {
R_ASSERT(fsDirRead(&dir, &read_entries, 1, &this->dir_entry));
if (read_entries != 1) {
break;
}
AMS_ASSERT(this->dir_entry.type == FsDirEntryType_Dir || this->dir_entry.type == FsDirEntryType_File);
if (this->dir_entry.type == FsDirEntryType_Dir) {
BuildDirectoryContext *real_child = nullptr;
this->AddDirectory(&real_child, parent, std::make_unique<BuildDirectoryContext>(this->dir_entry.name, strlen(this->dir_entry.name)));
AMS_ASSERT(real_child != nullptr);
child_dirs[cur_child_dir_ind++] = real_child;
AMS_ASSERT(cur_child_dir_ind <= num_child_dirs);
} else /* if (this->dir_entry.type == FsDirEntryType_File) */ {
this->AddFile(parent, std::make_unique<BuildFileContext>(this->dir_entry.name, strlen(this->dir_entry.name), this->dir_entry.file_size, 0, this->cur_source_type));
}
}
}
AMS_ASSERT(num_child_dirs == cur_child_dir_ind);
for (s64 i = 0; i < num_child_dirs; i++) {
this->VisitDirectory(fs, child_dirs[i]);
}
}
}
void Builder::VisitDirectory(BuildDirectoryContext *parent, u32 parent_offset, const void *dir_table, size_t dir_table_size, const void *file_table, size_t file_table_size) {
const DirectoryEntry *parent_entry = GetDirectoryEntry(dir_table, parent_offset);
if (parent_entry->file != EmptyEntry) {
const FileEntry *cur_file = GetFileEntry(file_table, parent_entry->file);
while (true) {
this->AddFile(parent, std::make_unique<BuildFileContext>(cur_file->name, cur_file->name_size, cur_file->size, cur_file->offset, this->cur_source_type));
if (cur_file->sibling == EmptyEntry) {
break;
}
cur_file = GetFileEntry(file_table, cur_file->sibling);
}
}
if (parent_entry->child != EmptyEntry) {
const DirectoryEntry *cur_child = GetDirectoryEntry(dir_table, parent_entry->child);
u32 cur_child_offset = parent_entry->child;
while (true) {
BuildDirectoryContext *real_child = nullptr;
this->AddDirectory(&real_child, parent, std::make_unique<BuildDirectoryContext>(cur_child->name, cur_child->name_size));
AMS_ASSERT(real_child != nullptr);
this->VisitDirectory(real_child, cur_child_offset, dir_table, dir_table_size, file_table, file_table_size);
if (cur_child->sibling == EmptyEntry) {
break;
}
cur_child_offset = cur_child->sibling;
cur_child = GetDirectoryEntry(dir_table, cur_child_offset);
}
}
}
void Builder::AddSdFiles() {
/* Open Sd Card filesystem. */
FsFileSystem sd_filesystem;
R_ASSERT(fsOpenSdCardFileSystem(&sd_filesystem));
ON_SCOPE_EXIT { fsFsClose(&sd_filesystem); };
/* If there is no romfs folder on the SD, don't bother continuing. */
{
FsDir dir;
if (R_FAILED(mitm::fs::OpenAtmosphereRomfsDirectory(&dir, this->program_id, this->root->path.get(), OpenDirectoryMode_Directory, &sd_filesystem))) {
return;
}
fsDirClose(&dir);
}
this->cur_source_type = DataSourceType::LooseSdFile;
this->VisitDirectory(&sd_filesystem, this->root);
}
void Builder::AddStorageFiles(ams::fs::IStorage *storage, DataSourceType source_type) {
Header header;
R_ASSERT(storage->Read(0, &header, sizeof(Header)));
AMS_ASSERT(header.header_size == sizeof(Header));
/* Read tables. */
void *tables = std::malloc(header.dir_table_size + header.file_table_size);
ON_SCOPE_EXIT { std::free(tables); };
void *dir_table = tables;
void *file_table = reinterpret_cast<void *>(reinterpret_cast<uintptr_t>(tables) + header.dir_table_size);
R_ASSERT(storage->Read(header.dir_table_ofs, dir_table, size_t(header.dir_table_size)));
R_ASSERT(storage->Read(header.file_table_ofs, file_table, size_t(header.file_table_size)));
this->cur_source_type = source_type;
this->VisitDirectory(this->root, 0x0, dir_table, size_t(header.dir_table_size), file_table, size_t(header.file_table_size));
}
void Builder::Build(std::vector<SourceInfo> *out_infos) {
/* Clear output. */
out_infos->clear();
/* Open an SD card filesystem. */
FsFileSystem sd_filesystem;
R_ASSERT(fsOpenSdCardFileSystem(&sd_filesystem));
ON_SCOPE_EXIT { fsFsClose(&sd_filesystem); };
/* Calculate hash table sizes. */
const size_t num_dir_hash_table_entries = GetHashTableSize(this->num_dirs);
const size_t num_file_hash_table_entries = GetHashTableSize(this->num_files);
this->dir_hash_table_size = sizeof(u32) * num_dir_hash_table_entries;
this->file_hash_table_size = sizeof(u32) * num_file_hash_table_entries;
/* Allocate metadata, make pointers. */
Header *header = reinterpret_cast<Header *>(std::malloc(sizeof(Header)));
std::memset(header, 0x00, sizeof(*header));
/* Open metadata file. */
const size_t metadata_size = this->dir_hash_table_size + this->dir_table_size + this->file_hash_table_size + this->file_table_size;
FsFile metadata_file;
R_ASSERT(mitm::fs::CreateAndOpenAtmosphereSdFile(&metadata_file, this->program_id, "romfs_metadata.bin", metadata_size));
/* Ensure later hash tables will have correct defaults. */
static_assert(EmptyEntry == 0xFFFFFFFF);
/* Emplace metadata source info. */
out_infos->emplace_back(0, sizeof(*header), DataSourceType::Memory, header);
/* Process Files. */
{
u32 entry_offset = 0;
BuildFileContext *cur_file = nullptr;
BuildFileContext *prev_file = nullptr;
for (const auto &it : this->files) {
cur_file = it.get();
/* By default, pad to 0x10 alignment. */
this->file_partition_size = util::AlignUp(this->file_partition_size, 0x10);
/* Check if extra padding is present in original source, preserve it to make our life easier. */
const bool is_storage_or_file = cur_file->source_type == DataSourceType::Storage || cur_file->source_type == DataSourceType::File;
if (prev_file != nullptr && prev_file->source_type == cur_file->source_type && is_storage_or_file) {
const s64 expected = this->file_partition_size - prev_file->offset + prev_file->orig_offset;
if (expected != cur_file->orig_offset) {
AMS_ASSERT(expected <= cur_file->orig_offset);
this->file_partition_size += cur_file->orig_offset - expected;
}
}
/* Calculate offsets. */
cur_file->offset = this->file_partition_size;
this->file_partition_size += cur_file->size;
cur_file->entry_offset = entry_offset;
entry_offset += sizeof(FileEntry) + util::AlignUp(cur_file->path_len, 4);
/* Save current file as prev for next iteration. */
prev_file = cur_file;
}
/* Assign deferred parent/sibling ownership. */
for (auto it = this->files.rbegin(); it != this->files.rend(); it++) {
cur_file = it->get();
cur_file->sibling = cur_file->parent->file;
cur_file->parent->file = cur_file;
}
}
/* Process Directories. */
{
u32 entry_offset = 0;
BuildDirectoryContext *cur_dir = nullptr;
for (const auto &it : this->directories) {
cur_dir = it.get();
cur_dir->entry_offset = entry_offset;
entry_offset += sizeof(DirectoryEntry) + util::AlignUp(cur_dir->path_len, 4);
}
/* Assign deferred parent/sibling ownership. */
for (auto it = this->directories.rbegin(); it != this->directories.rend(); it++) {
cur_dir = it->get();
if (cur_dir == this->root) {
continue;
}
cur_dir->sibling = cur_dir->parent->child;
cur_dir->parent->child = cur_dir;
}
}
/* Populate file tables. */
{
void *ft_buf = std::malloc(this->file_table_size);
void *fht_buf = std::malloc(this->file_hash_table_size);
ON_SCOPE_EXIT { std::free(fht_buf); std::free(ft_buf); };
u32 *file_hash_table = reinterpret_cast<u32 *>(fht_buf);
FileEntry *file_table = reinterpret_cast<FileEntry *>(ft_buf);
std::memset(file_hash_table, 0xFF, this->file_hash_table_size);
for (const auto &it : this->files) {
BuildFileContext *cur_file = it.get();
FileEntry *cur_entry = GetFileEntry(file_table, cur_file->entry_offset);
/* Set entry fields. */
cur_entry->parent = cur_file->parent->entry_offset;
cur_entry->sibling = (cur_file->sibling == nullptr) ? EmptyEntry : cur_file->sibling->entry_offset;
cur_entry->offset = cur_file->offset;
cur_entry->size = cur_file->size;
/* Insert into hash table. */
const u32 name_size = cur_file->path_len;
const size_t hash_ind = CalculatePathHash(cur_entry->parent, cur_file->path.get(), 0, name_size) % num_file_hash_table_entries;
cur_entry->hash = file_hash_table[hash_ind];
file_hash_table[hash_ind] = cur_file->entry_offset;
/* Set name. */
cur_entry->name_size = name_size;
if (name_size) {
std::memcpy(cur_entry->name, cur_file->path.get(), name_size);
for (size_t i = name_size; i < util::AlignUp(name_size, 4); i++) {
cur_entry->name[i] = 0;
}
}
/* Emplace a source. */
switch (cur_file->source_type) {
case DataSourceType::Storage:
case DataSourceType::File:
{
/* Try to compact if possible. */
auto &back = out_infos->back();
if (back.source_type == cur_file->source_type) {
back.size = cur_file->offset + FilePartitionOffset + cur_file->size - back.virtual_offset;
} else {
out_infos->emplace_back(cur_file->offset + FilePartitionOffset, cur_file->size, cur_file->source_type, cur_file->orig_offset + FilePartitionOffset);
}
}
break;
case DataSourceType::LooseSdFile:
{
char *new_path = new char[cur_file->GetPathLength() + 1];
cur_file->GetPath(new_path);
out_infos->emplace_back(cur_file->offset + FilePartitionOffset, cur_file->size, cur_file->source_type, new_path);
}
break;
AMS_UNREACHABLE_DEFAULT_CASE();
}
}
/* Write to file. */
R_ASSERT(fsFileWrite(&metadata_file, this->dir_hash_table_size + this->dir_table_size, file_hash_table, this->file_hash_table_size, FsWriteOption_None));
R_ASSERT(fsFileWrite(&metadata_file, this->dir_hash_table_size + this->dir_table_size + this->file_hash_table_size, file_table, this->file_table_size, FsWriteOption_None));
}
/* Populate directory tables. */
{
void *dt_buf = std::malloc(this->dir_table_size);
void *dht_buf = std::malloc(this->dir_hash_table_size);
ON_SCOPE_EXIT { std::free(dht_buf); std::free(dt_buf); };
u32 *dir_hash_table = reinterpret_cast<u32 *>(dht_buf);
DirectoryEntry *dir_table = reinterpret_cast<DirectoryEntry *>(dt_buf);
std::memset(dir_hash_table, 0xFF, this->dir_hash_table_size);
for (const auto &it : this->directories) {
BuildDirectoryContext *cur_dir = it.get();
DirectoryEntry *cur_entry = GetDirectoryEntry(dir_table, cur_dir->entry_offset);
/* Set entry fields. */
cur_entry->parent = cur_dir == this->root ? 0 : cur_dir->parent->entry_offset;
cur_entry->sibling = (cur_dir->sibling == nullptr) ? EmptyEntry : cur_dir->sibling->entry_offset;
cur_entry->child = (cur_dir->child == nullptr) ? EmptyEntry : cur_dir->child->entry_offset;
cur_entry->file = (cur_dir->file == nullptr) ? EmptyEntry : cur_dir->file->entry_offset;
/* Insert into hash table. */
const u32 name_size = cur_dir->path_len;
const size_t hash_ind = CalculatePathHash(cur_entry->parent, cur_dir->path.get(), 0, name_size) % num_dir_hash_table_entries;
cur_entry->hash = dir_hash_table[hash_ind];
dir_hash_table[hash_ind] = cur_dir->entry_offset;
/* Set name. */
cur_entry->name_size = name_size;
if (name_size) {
std::memcpy(cur_entry->name, cur_dir->path.get(), name_size);
for (size_t i = name_size; i < util::AlignUp(name_size, 4); i++) {
cur_entry->name[i] = 0;
}
}
}
/* Write to file. */
R_ASSERT(fsFileWrite(&metadata_file, 0, dir_hash_table, this->dir_hash_table_size, FsWriteOption_None));
R_ASSERT(fsFileWrite(&metadata_file, this->dir_hash_table_size, dir_table, this->dir_table_size, FsWriteOption_None));
}
/* Delete maps. */
this->root = nullptr;
this->directories.clear();
this->files.clear();
/* Set header fields. */
header->header_size = sizeof(*header);
header->file_hash_table_size = this->file_hash_table_size;
header->file_table_size = this->file_table_size;
header->dir_hash_table_size = this->dir_hash_table_size;
header->dir_table_size = this->dir_table_size;
header->file_partition_ofs = FilePartitionOffset;
header->dir_hash_table_ofs = util::AlignUp(FilePartitionOffset + this->file_partition_size, 4);
header->dir_table_ofs = header->dir_hash_table_ofs + header->dir_hash_table_size;
header->file_hash_table_ofs = header->dir_table_ofs + header->dir_table_size;
header->file_table_ofs = header->file_hash_table_ofs + header->file_hash_table_size;
/* Save metadata to the SD card, to save on memory space. */
{
R_ASSERT(fsFileFlush(&metadata_file));
out_infos->emplace_back(header->dir_hash_table_ofs, metadata_size, DataSourceType::Metadata, new RemoteFile(metadata_file));
}
}
}
}