FS: Stream RomFS from file instead of loading all of it to memory

1 files changed, 6 insertions, 7 deletions

diff --git a/src/core/file_sys/ivfc_archive.cpp b/src/core/file_sys/ivfc_archive.cpp
index c88b39bc..2b88b1d5 100644
--- a/src/core/file_sys/ivfc_archive.cpp
+++ b/src/core/file_sys/ivfc_archive.cpp
@@ -16,15 +16,12 @@
 
 namespace FileSys {
 
-IVFCArchive::IVFCArchive(std::shared_ptr<const std::vector<u8>> data) : data(data) {
-}
-
 std::string IVFCArchive::GetName() const {
     return "IVFC";
 }
 
 std::unique_ptr<FileBackend> IVFCArchive::OpenFile(const Path& path, const Mode mode) const {
-    return Common::make_unique<IVFCFile>(data);
+    return Common::make_unique<IVFCFile>(romfs_file, data_offset, data_size);
 }
 
 bool IVFCArchive::DeleteFile(const Path& path) const {
@@ -66,8 +63,10 @@ std::unique_ptr<DirectoryBackend> IVFCArchive::OpenDirectory(const Path& path) c
 
 size_t IVFCFile::Read(const u64 offset, const u32 length, u8* buffer) const {
     LOG_TRACE(Service_FS, "called offset=%llu, length=%d", offset, length);
-    memcpy(buffer, data->data() + offset, length);
-    return length;
+    romfs_file->Seek(data_offset + offset, SEEK_SET);
+    u32 read_length = (u32)std::min((u64)length, data_size - offset);
+
+    return romfs_file->ReadBytes(buffer, read_length);
 }
 
 size_t IVFCFile::Write(const u64 offset, const u32 length, const u32 flush, const u8* buffer) const {
@@ -76,7 +75,7 @@ size_t IVFCFile::Write(const u64 offset, const u32 length, const u32 flush, cons
 }
 
 size_t IVFCFile::GetSize() const {
-    return sizeof(u8) * data->size();
+    return data_size; // TODO: return value will overflow on 32-bit machines
 }
 
 bool IVFCFile::SetSize(const u64 size) const {