1 files changed, 551 insertions, 0 deletions
diff --git a/src/core/file_sys/vfs/vfs.cpp b/src/core/file_sys/vfs/vfs.cpp
new file mode 100644
index 000000000..a04292760
--- /dev/null
+++ b/src/core/file_sys/vfs/vfs.cpp
@@ -0,0 +1,551 @@
+// SPDX-FileCopyrightText: Copyright 2018 yuzu Emulator Project
+// SPDX-License-Identifier: GPL-2.0-or-later
+
+#include <algorithm>
+#include <numeric>
+#include <string>
+#include "common/fs/path_util.h"
+#include "core/file_sys/vfs/vfs.h"
+
+namespace FileSys {
+
+VfsFilesystem::VfsFilesystem(VirtualDir root_) : root(std::move(root_)) {}
+
+VfsFilesystem::~VfsFilesystem() = default;
+
+std::string VfsFilesystem::GetName() const {
+    return root->GetName();
+}
+
+bool VfsFilesystem::IsReadable() const {
+    return root->IsReadable();
+}
+
+bool VfsFilesystem::IsWritable() const {
+    return root->IsWritable();
+}
+
+VfsEntryType VfsFilesystem::GetEntryType(std::string_view path_) const {
+    const auto path = Common::FS::SanitizePath(path_);
+    if (root->GetFileRelative(path) != nullptr)
+        return VfsEntryType::File;
+    if (root->GetDirectoryRelative(path) != nullptr)
+        return VfsEntryType::Directory;
+
+    return VfsEntryType::None;
+}
+
+VirtualFile VfsFilesystem::OpenFile(std::string_view path_, OpenMode perms) {
+    const auto path = Common::FS::SanitizePath(path_);
+    return root->GetFileRelative(path);
+}
+
+VirtualFile VfsFilesystem::CreateFile(std::string_view path_, OpenMode perms) {
+    const auto path = Common::FS::SanitizePath(path_);
+    return root->CreateFileRelative(path);
+}
+
+VirtualFile VfsFilesystem::CopyFile(std::string_view old_path_, std::string_view new_path_) {
+    const auto old_path = Common::FS::SanitizePath(old_path_);
+    const auto new_path = Common::FS::SanitizePath(new_path_);
+
+    // VfsDirectory impls are only required to implement copy across the current directory.
+    if (Common::FS::GetParentPath(old_path) == Common::FS::GetParentPath(new_path)) {
+        if (!root->Copy(Common::FS::GetFilename(old_path), Common::FS::GetFilename(new_path)))
+            return nullptr;
+        return OpenFile(new_path, OpenMode::ReadWrite);
+    }
+
+    // Do it using RawCopy. Non-default impls are encouraged to optimize this.
+    const auto old_file = OpenFile(old_path, OpenMode::Read);
+    if (old_file == nullptr)
+        return nullptr;
+    auto new_file = OpenFile(new_path, OpenMode::Read);
+    if (new_file != nullptr)
+        return nullptr;
+    new_file = CreateFile(new_path, OpenMode::Write);
+    if (new_file == nullptr)
+        return nullptr;
+    if (!VfsRawCopy(old_file, new_file))
+        return nullptr;
+    return new_file;
+}
+
+VirtualFile VfsFilesystem::MoveFile(std::string_view old_path, std::string_view new_path) {
+    const auto sanitized_old_path = Common::FS::SanitizePath(old_path);
+    const auto sanitized_new_path = Common::FS::SanitizePath(new_path);
+
+    // Again, non-default impls are highly encouraged to provide a more optimized version of this.
+    auto out = CopyFile(sanitized_old_path, sanitized_new_path);
+    if (out == nullptr)
+        return nullptr;
+    if (DeleteFile(sanitized_old_path))
+        return out;
+    return nullptr;
+}
+
+bool VfsFilesystem::DeleteFile(std::string_view path_) {
+    const auto path = Common::FS::SanitizePath(path_);
+    auto parent = OpenDirectory(Common::FS::GetParentPath(path), OpenMode::Write);
+    if (parent == nullptr)
+        return false;
+    return parent->DeleteFile(Common::FS::GetFilename(path));
+}
+
+VirtualDir VfsFilesystem::OpenDirectory(std::string_view path_, OpenMode perms) {
+    const auto path = Common::FS::SanitizePath(path_);
+    return root->GetDirectoryRelative(path);
+}
+
+VirtualDir VfsFilesystem::CreateDirectory(std::string_view path_, OpenMode perms) {
+    const auto path = Common::FS::SanitizePath(path_);
+    return root->CreateDirectoryRelative(path);
+}
+
+VirtualDir VfsFilesystem::CopyDirectory(std::string_view old_path_, std::string_view new_path_) {
+    const auto old_path = Common::FS::SanitizePath(old_path_);
+    const auto new_path = Common::FS::SanitizePath(new_path_);
+
+    // Non-default impls are highly encouraged to provide a more optimized version of this.
+    auto old_dir = OpenDirectory(old_path, OpenMode::Read);
+    if (old_dir == nullptr)
+        return nullptr;
+    auto new_dir = OpenDirectory(new_path, OpenMode::Read);
+    if (new_dir != nullptr)
+        return nullptr;
+    new_dir = CreateDirectory(new_path, OpenMode::Write);
+    if (new_dir == nullptr)
+        return nullptr;
+
+    for (const auto& file : old_dir->GetFiles()) {
+        const auto x = CopyFile(old_path + '/' + file->GetName(), new_path + '/' + file->GetName());
+        if (x == nullptr)
+            return nullptr;
+    }
+
+    for (const auto& dir : old_dir->GetSubdirectories()) {
+        const auto x =
+            CopyDirectory(old_path + '/' + dir->GetName(), new_path + '/' + dir->GetName());
+        if (x == nullptr)
+            return nullptr;
+    }
+
+    return new_dir;
+}
+
+VirtualDir VfsFilesystem::MoveDirectory(std::string_view old_path, std::string_view new_path) {
+    const auto sanitized_old_path = Common::FS::SanitizePath(old_path);
+    const auto sanitized_new_path = Common::FS::SanitizePath(new_path);
+
+    // Non-default impls are highly encouraged to provide a more optimized version of this.
+    auto out = CopyDirectory(sanitized_old_path, sanitized_new_path);
+    if (out == nullptr)
+        return nullptr;
+    if (DeleteDirectory(sanitized_old_path))
+        return out;
+    return nullptr;
+}
+
+bool VfsFilesystem::DeleteDirectory(std::string_view path_) {
+    const auto path = Common::FS::SanitizePath(path_);
+    auto parent = OpenDirectory(Common::FS::GetParentPath(path), OpenMode::Write);
+    if (parent == nullptr)
+        return false;
+    return parent->DeleteSubdirectoryRecursive(Common::FS::GetFilename(path));
+}
+
+VfsFile::~VfsFile() = default;
+
+std::string VfsFile::GetExtension() const {
+    return std::string(Common::FS::GetExtensionFromFilename(GetName()));
+}
+
+VfsDirectory::~VfsDirectory() = default;
+
+std::optional<u8> VfsFile::ReadByte(std::size_t offset) const {
+    u8 out{};
+    const std::size_t size = Read(&out, sizeof(u8), offset);
+    if (size == 1) {
+        return out;
+    }
+
+    return std::nullopt;
+}
+
+std::vector<u8> VfsFile::ReadBytes(std::size_t size, std::size_t offset) const {
+    std::vector<u8> out(size);
+    std::size_t read_size = Read(out.data(), size, offset);
+    out.resize(read_size);
+    return out;
+}
+
+std::vector<u8> VfsFile::ReadAllBytes() const {
+    return ReadBytes(GetSize());
+}
+
+bool VfsFile::WriteByte(u8 data, std::size_t offset) {
+    return Write(&data, 1, offset) == 1;
+}
+
+std::size_t VfsFile::WriteBytes(const std::vector<u8>& data, std::size_t offset) {
+    return Write(data.data(), data.size(), offset);
+}
+
+std::string VfsFile::GetFullPath() const {
+    if (GetContainingDirectory() == nullptr)
+        return '/' + GetName();
+
+    return GetContainingDirectory()->GetFullPath() + '/' + GetName();
+}
+
+VirtualFile VfsDirectory::GetFileRelative(std::string_view path) const {
+    auto vec = Common::FS::SplitPathComponents(path);
+    if (vec.empty()) {
+        return nullptr;
+    }
+
+    if (vec.size() == 1) {
+        return GetFile(vec[0]);
+    }
+
+    auto dir = GetSubdirectory(vec[0]);
+    for (std::size_t component = 1; component < vec.size() - 1; ++component) {
+        if (dir == nullptr) {
+            return nullptr;
+        }
+
+        dir = dir->GetSubdirectory(vec[component]);
+    }
+
+    if (dir == nullptr) {
+        return nullptr;
+    }
+
+    return dir->GetFile(vec.back());
+}
+
+VirtualFile VfsDirectory::GetFileAbsolute(std::string_view path) const {
+    if (IsRoot()) {
+        return GetFileRelative(path);
+    }
+
+    return GetParentDirectory()->GetFileAbsolute(path);
+}
+
+VirtualDir VfsDirectory::GetDirectoryRelative(std::string_view path) const {
+    auto vec = Common::FS::SplitPathComponents(path);
+    if (vec.empty()) {
+        // TODO(DarkLordZach): Return this directory if path is '/' or similar. Can't currently
+        // because of const-ness
+        return nullptr;
+    }
+
+    auto dir = GetSubdirectory(vec[0]);
+    for (std::size_t component = 1; component < vec.size(); ++component) {
+        if (dir == nullptr) {
+            return nullptr;
+        }
+
+        dir = dir->GetSubdirectory(vec[component]);
+    }
+
+    return dir;
+}
+
+VirtualDir VfsDirectory::GetDirectoryAbsolute(std::string_view path) const {
+    if (IsRoot()) {
+        return GetDirectoryRelative(path);
+    }
+
+    return GetParentDirectory()->GetDirectoryAbsolute(path);
+}
+
+VirtualFile VfsDirectory::GetFile(std::string_view name) const {
+    const auto& files = GetFiles();
+    const auto iter = std::find_if(files.begin(), files.end(),
+                                   [&name](const auto& file1) { return name == file1->GetName(); });
+    return iter == files.end() ? nullptr : *iter;
+}
+
+FileTimeStampRaw VfsDirectory::GetFileTimeStamp([[maybe_unused]] std::string_view path) const {
+    return {};
+}
+
+VirtualDir VfsDirectory::GetSubdirectory(std::string_view name) const {
+    const auto& subs = GetSubdirectories();
+    const auto iter = std::find_if(subs.begin(), subs.end(),
+                                   [&name](const auto& file1) { return name == file1->GetName(); });
+    return iter == subs.end() ? nullptr : *iter;
+}
+
+bool VfsDirectory::IsRoot() const {
+    return GetParentDirectory() == nullptr;
+}
+
+std::size_t VfsDirectory::GetSize() const {
+    const auto& files = GetFiles();
+    const auto sum_sizes = [](const auto& range) {
+        return std::accumulate(range.begin(), range.end(), 0ULL,
+                               [](const auto& f1, const auto& f2) { return f1 + f2->GetSize(); });
+    };
+
+    const auto file_total = sum_sizes(files);
+    const auto& sub_dir = GetSubdirectories();
+    const auto subdir_total = sum_sizes(sub_dir);
+
+    return file_total + subdir_total;
+}
+
+VirtualFile VfsDirectory::CreateFileRelative(std::string_view path) {
+    auto vec = Common::FS::SplitPathComponents(path);
+    if (vec.empty()) {
+        return nullptr;
+    }
+
+    if (vec.size() == 1) {
+        return CreateFile(vec[0]);
+    }
+
+    auto dir = GetSubdirectory(vec[0]);
+    if (dir == nullptr) {
+        dir = CreateSubdirectory(vec[0]);
+        if (dir == nullptr) {
+            return nullptr;
+        }
+    }
+
+    return dir->CreateFileRelative(Common::FS::GetPathWithoutTop(path));
+}
+
+VirtualFile VfsDirectory::CreateFileAbsolute(std::string_view path) {
+    if (IsRoot()) {
+        return CreateFileRelative(path);
+    }
+
+    return GetParentDirectory()->CreateFileAbsolute(path);
+}
+
+VirtualDir VfsDirectory::CreateDirectoryRelative(std::string_view path) {
+    auto vec = Common::FS::SplitPathComponents(path);
+    if (vec.empty()) {
+        return nullptr;
+    }
+
+    if (vec.size() == 1) {
+        return CreateSubdirectory(vec[0]);
+    }
+
+    auto dir = GetSubdirectory(vec[0]);
+    if (dir == nullptr) {
+        dir = CreateSubdirectory(vec[0]);
+        if (dir == nullptr) {
+            return nullptr;
+        }
+    }
+
+    return dir->CreateDirectoryRelative(Common::FS::GetPathWithoutTop(path));
+}
+
+VirtualDir VfsDirectory::CreateDirectoryAbsolute(std::string_view path) {
+    if (IsRoot()) {
+        return CreateDirectoryRelative(path);
+    }
+
+    return GetParentDirectory()->CreateDirectoryAbsolute(path);
+}
+
+bool VfsDirectory::DeleteSubdirectoryRecursive(std::string_view name) {
+    auto dir = GetSubdirectory(name);
+    if (dir == nullptr) {
+        return false;
+    }
+
+    bool success = true;
+    for (const auto& file : dir->GetFiles()) {
+        if (!DeleteFile(file->GetName())) {
+            success = false;
+        }
+    }
+
+    for (const auto& sdir : dir->GetSubdirectories()) {
+        if (!dir->DeleteSubdirectoryRecursive(sdir->GetName())) {
+            success = false;
+        }
+    }
+
+    return success;
+}
+
+bool VfsDirectory::CleanSubdirectoryRecursive(std::string_view name) {
+    auto dir = GetSubdirectory(name);
+    if (dir == nullptr) {
+        return false;
+    }
+
+    bool success = true;
+    for (const auto& file : dir->GetFiles()) {
+        if (!dir->DeleteFile(file->GetName())) {
+            success = false;
+        }
+    }
+
+    for (const auto& sdir : dir->GetSubdirectories()) {
+        if (!dir->DeleteSubdirectoryRecursive(sdir->GetName())) {
+            success = false;
+        }
+    }
+
+    return success;
+}
+
+bool VfsDirectory::Copy(std::string_view src, std::string_view dest) {
+    const auto f1 = GetFile(src);
+    auto f2 = CreateFile(dest);
+    if (f1 == nullptr || f2 == nullptr) {
+        return false;
+    }
+
+    if (!f2->Resize(f1->GetSize())) {
+        DeleteFile(dest);
+        return false;
+    }
+
+    return f2->WriteBytes(f1->ReadAllBytes()) == f1->GetSize();
+}
+
+std::map<std::string, VfsEntryType, std::less<>> VfsDirectory::GetEntries() const {
+    std::map<std::string, VfsEntryType, std::less<>> out;
+    for (const auto& dir : GetSubdirectories())
+        out.emplace(dir->GetName(), VfsEntryType::Directory);
+    for (const auto& file : GetFiles())
+        out.emplace(file->GetName(), VfsEntryType::File);
+    return out;
+}
+
+std::string VfsDirectory::GetFullPath() const {
+    if (IsRoot())
+        return GetName();
+
+    return GetParentDirectory()->GetFullPath() + '/' + GetName();
+}
+
+bool ReadOnlyVfsDirectory::IsWritable() const {
+    return false;
+}
+
+bool ReadOnlyVfsDirectory::IsReadable() const {
+    return true;
+}
+
+VirtualDir ReadOnlyVfsDirectory::CreateSubdirectory(std::string_view name) {
+    return nullptr;
+}
+
+VirtualFile ReadOnlyVfsDirectory::CreateFile(std::string_view name) {
+    return nullptr;
+}
+
+VirtualFile ReadOnlyVfsDirectory::CreateFileAbsolute(std::string_view path) {
+    return nullptr;
+}
+
+VirtualFile ReadOnlyVfsDirectory::CreateFileRelative(std::string_view path) {
+    return nullptr;
+}
+
+VirtualDir ReadOnlyVfsDirectory::CreateDirectoryAbsolute(std::string_view path) {
+    return nullptr;
+}
+
+VirtualDir ReadOnlyVfsDirectory::CreateDirectoryRelative(std::string_view path) {
+    return nullptr;
+}
+
+bool ReadOnlyVfsDirectory::DeleteSubdirectory(std::string_view name) {
+    return false;
+}
+
+bool ReadOnlyVfsDirectory::DeleteSubdirectoryRecursive(std::string_view name) {
+    return false;
+}
+
+bool ReadOnlyVfsDirectory::CleanSubdirectoryRecursive(std::string_view name) {
+    return false;
+}
+
+bool ReadOnlyVfsDirectory::DeleteFile(std::string_view name) {
+    return false;
+}
+
+bool ReadOnlyVfsDirectory::Rename(std::string_view name) {
+    return false;
+}
+
+bool DeepEquals(const VirtualFile& file1, const VirtualFile& file2, std::size_t block_size) {
+    if (file1->GetSize() != file2->GetSize())
+        return false;
+
+    std::vector<u8> f1_v(block_size);
+    std::vector<u8> f2_v(block_size);
+    for (std::size_t i = 0; i < file1->GetSize(); i += block_size) {
+        auto f1_vs = file1->Read(f1_v.data(), block_size, i);
+        auto f2_vs = file2->Read(f2_v.data(), block_size, i);
+
+        if (f1_vs != f2_vs)
+            return false;
+        auto iters = std::mismatch(f1_v.begin(), f1_v.end(), f2_v.begin(), f2_v.end());
+        if (iters.first != f1_v.end() && iters.second != f2_v.end())
+            return false;
+    }
+
+    return true;
+}
+
+bool VfsRawCopy(const VirtualFile& src, const VirtualFile& dest, std::size_t block_size) {
+    if (src == nullptr || dest == nullptr || !src->IsReadable() || !dest->IsWritable())
+        return false;
+    if (!dest->Resize(src->GetSize()))
+        return false;
+
+    std::vector<u8> temp(std::min(block_size, src->GetSize()));
+    for (std::size_t i = 0; i < src->GetSize(); i += block_size) {
+        const auto read = std::min(block_size, src->GetSize() - i);
+
+        if (src->Read(temp.data(), read, i) != read) {
+            return false;
+        }
+
+        if (dest->Write(temp.data(), read, i) != read) {
+            return false;
+        }
+    }
+
+    return true;
+}
+
+bool VfsRawCopyD(const VirtualDir& src, const VirtualDir& dest, std::size_t block_size) {
+    if (src == nullptr || dest == nullptr || !src->IsReadable() || !dest->IsWritable())
+        return false;
+
+    for (const auto& file : src->GetFiles()) {
+        const auto out = dest->CreateFile(file->GetName());
+        if (!VfsRawCopy(file, out, block_size))
+            return false;
+    }
+
+    for (const auto& dir : src->GetSubdirectories()) {
+        const auto out = dest->CreateSubdirectory(dir->GetName());
+        if (!VfsRawCopyD(dir, out, block_size))
+            return false;
+    }
+
+    return true;
+}
+
+VirtualDir GetOrCreateDirectoryRelative(const VirtualDir& rel, std::string_view path) {
+    const auto res = rel->GetDirectoryRelative(path);
+    if (res == nullptr)
+        return rel->CreateDirectoryRelative(path);
+    return res;
+}
+} // namespace FileSys