ObjLoading: Add basis for IPakEntryReadStream to read ipak entries

src/ObjLoading/ObjContainer/IPak/IPakEntryReadStream.h

@@ -0,0 +1,36 @@
+#pragma once
+
+#include "IPakStreamManager.h"
+#include "Utils/FileAPI.h"
+#include <mutex>
+
+class IPakEntryReadStream final : public FileAPI::IFile
+{
+    static constexpr size_t IPAK_CHUNK_SIZE = 0x8000;
+    static constexpr size_t IPAK_CHUNK_COUNT_PER_READ = 0x8;
+
+    uint8_t* m_buffer;
+    IFile* m_file;
+    IPakStreamManager* m_stream_manager;
+    std::mutex* m_read_mutex;
+
+    int64_t m_pos;
+    int64_t m_base_pos;
+    int64_t m_end_pos;
+    int64_t m_buffer_pos;
+
+    static int64_t Align(int64_t num, int64_t alignTo);
+
+public:
+    IPakEntryReadStream(IFile* file, IPakStreamManager* streamManager, std::mutex* readMutex, int64_t startOffset, size_t length);
+    ~IPakEntryReadStream() override;
+    bool IsOpen() override;
+    size_t Read(void* buffer, size_t elementSize, size_t elementCount) override;
+    size_t Write(const void* data, size_t elementSize, size_t elementCount) override;
+    void Skip(int64_t amount) override;
+    size_t Printf(const char* fmt, ...) override;
+    int64_t Pos() override;
+    void Goto(int64_t pos) override;
+    void GotoEnd() override;
+    void Close() override;
+};