assimp.assimp/code/CApi/CInterfaceIOWrapper.h

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Open Asset Import Library (assimp)
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/** @file aiFileIO -> IOSystem wrapper*/

#ifndef AI_CIOSYSTEM_H_INCLUDED
#define AI_CIOSYSTEM_H_INCLUDED

#include <assimp/cfileio.h>
#include <assimp/IOStream.hpp>
#include <assimp/IOSystem.hpp>
#include <assimp/ai_assert.h>

namespace Assimp {

class CIOSystemWrapper;

// ------------------------------------------------------------------------------------------------
/// @brief Custom IOStream implementation for the C-API-
// ------------------------------------------------------------------------------------------------
class CIOStreamWrapper final : public IOStream {
public:
    explicit CIOStreamWrapper(aiFile *pFile, CIOSystemWrapper *io);
    ~CIOStreamWrapper() override;
    size_t Read(void *pvBuffer, size_t pSize, size_t pCount) override;
    size_t Write(const void *pvBuffer, size_t pSize, size_t pCount) override;
    aiReturn Seek(size_t pOffset, aiOrigin pOrigin) override;
    size_t Tell(void) const override;
    size_t FileSize() const override;
    void Flush() override;

private:
    aiFile *mFile;
    CIOSystemWrapper *mIO;
};

inline CIOStreamWrapper::CIOStreamWrapper(aiFile *pFile, CIOSystemWrapper *io) :
        mFile(pFile),
        mIO(io) {
    ai_assert(io != nullptr);
}

// ------------------------------------------------------------------------------------------------
/// @brief Custom IO-System wrapper implementation for the C-API.
// ------------------------------------------------------------------------------------------------
class CIOSystemWrapper final : public IOSystem {
    friend class CIOStreamWrapper;

public:
    explicit CIOSystemWrapper(aiFileIO *pFile);
    ~CIOSystemWrapper() override = default;
    bool Exists(const char *pFile) const override;
    char getOsSeparator() const override;
    IOStream *Open(const char *pFile, const char *pMode = "rb") override;
    void Close(IOStream *pFile) override;

private:
    aiFileIO *mFileSystem;
};

inline CIOSystemWrapper::CIOSystemWrapper(aiFileIO *pFile) : mFileSystem(pFile) {
    ai_assert(pFile != nullptr);
}

} // namespace Assimp

#endif // AI_CIOSYSTEM_H_INCLUDED