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-rw-r--r--src/core/hle/romfs.cpp102
1 files changed, 102 insertions, 0 deletions
diff --git a/src/core/hle/romfs.cpp b/src/core/hle/romfs.cpp
new file mode 100644
index 000000000..3157df71d
--- /dev/null
+++ b/src/core/hle/romfs.cpp
@@ -0,0 +1,102 @@
+// Copyright 2017 Citra Emulator Project
+// Licensed under GPLv2 or any later version
+// Refer to the license.txt file included.
+
+#include <cstring>
+#include "common/swap.h"
+#include "core/hle/romfs.h"
+
+namespace RomFS {
+
+struct Header {
+ u32_le header_length;
+ u32_le dir_hash_table_offset;
+ u32_le dir_hash_table_length;
+ u32_le dir_table_offset;
+ u32_le dir_table_length;
+ u32_le file_hash_table_offset;
+ u32_le file_hash_table_length;
+ u32_le file_table_offset;
+ u32_le file_table_length;
+ u32_le data_offset;
+};
+
+static_assert(sizeof(Header) == 0x28, "Header has incorrect size");
+
+struct DirectoryMetadata {
+ u32_le parent_dir_offset;
+ u32_le next_dir_offset;
+ u32_le first_child_dir_offset;
+ u32_le first_file_offset;
+ u32_le same_hash_next_dir_offset;
+ u32_le name_length; // in bytes
+ // followed by directory name
+};
+
+static_assert(sizeof(DirectoryMetadata) == 0x18, "DirectoryMetadata has incorrect size");
+
+struct FileMetadata {
+ u32_le parent_dir_offset;
+ u32_le next_file_offset;
+ u64_le data_offset;
+ u64_le data_length;
+ u32_le same_hash_next_file_offset;
+ u32_le name_length; // in bytes
+ // followed by file name
+};
+
+static_assert(sizeof(FileMetadata) == 0x20, "FileMetadata has incorrect size");
+
+static bool MatchName(const u8* buffer, u32 name_length, const std::u16string& name) {
+ std::vector<char16_t> name_buffer(name_length / sizeof(char16_t));
+ std::memcpy(name_buffer.data(), buffer, name_length);
+ return name == std::u16string(name_buffer.begin(), name_buffer.end());
+}
+
+const u8* GetFilePointer(const u8* romfs, const std::vector<std::u16string>& path) {
+ constexpr u32 INVALID_FIELD = 0xFFFFFFFF;
+
+ // Split path into directory names and file name
+ std::vector<std::u16string> dir_names = path;
+ dir_names.pop_back();
+ const std::u16string& file_name = path.back();
+
+ Header header;
+ std::memcpy(&header, romfs, sizeof(header));
+
+ // Find directories of each level
+ DirectoryMetadata dir;
+ const u8* current_dir = romfs + header.dir_table_offset;
+ std::memcpy(&dir, current_dir, sizeof(dir));
+ for (const std::u16string& dir_name : dir_names) {
+ u32 child_dir_offset;
+ child_dir_offset = dir.first_child_dir_offset;
+ while (true) {
+ if (child_dir_offset == INVALID_FIELD) {
+ return nullptr;
+ }
+ const u8* current_child_dir = romfs + header.dir_table_offset + child_dir_offset;
+ std::memcpy(&dir, current_child_dir, sizeof(dir));
+ if (MatchName(current_child_dir + sizeof(dir), dir.name_length, dir_name)) {
+ current_dir = current_child_dir;
+ break;
+ }
+ child_dir_offset = dir.next_dir_offset;
+ }
+ }
+
+ // Find the file
+ FileMetadata file;
+ u32 file_offset = dir.first_file_offset;
+ while (file_offset != INVALID_FIELD) {
+ const u8* current_file = romfs + header.file_table_offset + file_offset;
+ std::memcpy(&file, current_file, sizeof(file));
+ if (MatchName(current_file + sizeof(file), file.name_length, file_name)) {
+ return romfs + header.data_offset + file.data_offset;
+ }
+ file_offset = file.next_file_offset;
+ }
+ return nullptr;
+}
+
+} // namespace RomFS