assimp.assimp/include/assimp/IOStream.hpp

/*
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Open Asset Import Library (assimp)
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*/
/** @file IOStream.hpp
 *  @brief File I/O wrappers for C++.
 */

#pragma once
#ifndef AI_IOSTREAM_H_INC
#define AI_IOSTREAM_H_INC

#ifdef __GNUC__
#   pragma GCC system_header
#endif

#include <assimp/types.h>

#ifndef __cplusplus
#   error This header requires C++ to be used. aiFileIO.h is the \
    corresponding C interface.
#endif

namespace Assimp {

// ----------------------------------------------------------------------------------
/** @brief CPP-API: Class to handle file I/O for C++
 *
 *  Derive an own implementation from this interface to provide custom IO handling
 *  to the Importer. If you implement this interface, be sure to also provide an
 *  implementation for IOSystem that creates instances of your custom IO class.
*/
class ASSIMP_API IOStream
#ifndef SWIG
    : public Intern::AllocateFromAssimpHeap
#endif
{
protected:
    /** Constructor protected, use IOSystem::Open() to create an instance. */
    IOStream() AI_NO_EXCEPT = default;

public:
    // -------------------------------------------------------------------
    /** @brief Destructor. Deleting the object closes the underlying file,
     * alternatively you may use IOSystem::Close() to release the file.
     */
    virtual ~IOStream() = default;

    // -------------------------------------------------------------------
    /** @brief Read from the file
     *
     * See fread() for more details
     * This fails for write-only files */
    virtual size_t Read(void* pvBuffer,
        size_t pSize,
        size_t pCount) = 0;

    // -------------------------------------------------------------------
    /** @brief Write to the file
    *
    * See fwrite() for more details
    * This fails for read-only files */
    virtual size_t Write(const void* pvBuffer,
        size_t pSize,
        size_t pCount) = 0;

    // -------------------------------------------------------------------
    /** @brief Set the read/write cursor of the file
     *
     * Note that the offset is _negative_ for aiOrigin_END.
     * See fseek() for more details */
    virtual aiReturn Seek(size_t pOffset,
        aiOrigin pOrigin) = 0;

    // -------------------------------------------------------------------
    /** @brief Get the current position of the read/write cursor
     *
     * See ftell() for more details */
    virtual size_t Tell() const = 0;

    // -------------------------------------------------------------------
    /** @brief Returns filesize
     *  Returns the filesize. */
    virtual size_t FileSize() const = 0;

    // -------------------------------------------------------------------
    /** @brief Flush the contents of the file buffer (for writers)
     *  See fflush() for more details.
     */
    virtual void Flush() = 0;
}; //! class IOStream

} //!namespace Assimp

#endif //!!AI_IOSTREAM_H_INC