#ifndef MEMORYREADER_HPP #define MEMORYREADER_HPP #include #include #include #include "Athena/IStreamReader.hpp" namespace Athena { namespace io { /*! \class MemoryReader * \brief A Stream class for reading data from a memory position * * A Class for reading binary data from a file or memory stream, * all work is done using a memory buffer, and not read directly from the disk * this allows for fast, flexible code as well as the ability to quickly modify data * \sa Stream */ class MemoryReader : public IStreamReader { public: /*! \brief This constructor references an existing buffer to read from. * * \param data The existing buffer * \param length The length of the existing buffer */ MemoryReader(const atUint8* data, atUint64 length); /*! \brief Sets the buffers position relative to the specified position.
* It seeks relative to the current position by default. * \param position where in the buffer to seek * \param origin The Origin to seek \sa SeekOrigin */ void seek(atInt64 pos, SeekOrigin origin = SeekOrigin::Current); /*! \brief Returns the current position in the stream. * * \return Int64 The current position in the stream. */ inline atUint64 position() const {return m_position;} /*! \brief Returns whether or not the stream is at the end. * * \return bool True if at end; False otherwise. */ inline atUint64 length() const {return m_length;} /*! \brief Sets the buffer to the given one, deleting the current one.
* BEWARE: As this deletes the current buffer it WILL cause a loss of data * if that was not the intent.
* Once you pass the data to setData DO NOT delete the buffer * as Stream now owns the address, this is done to keep memory usage down. * \param data The new buffer. * \param length The length of the new buffer. * \throw IOException */ void setData(const atUint8* data, atUint64 length); /*! \brief Returns a copy of the current buffer.
* Changes to the copy do not affect the buffer so it's perfectly safe to * directly edit the buffer and use setData to set the new information.
* However once you pass the data to setData DO NOT delete the buffer * as Stream now owns the address, this is done to keep memory usage down. * \return Uint8* The copy of the buffer. */ atUint8* data() const; /*! \brief Reads a specified number of bytes to user-allocated buffer * \param buf User-allocated buffer pointer * \param len Length to read * \return Number of bytes read */ atUint64 readUBytesToBuf(void* buf, atUint64 len); protected: const atUint8* m_data; atUint64 m_length; atUint64 m_position; }; class MemoryCopyReader : public MemoryReader { public: /*! \brief This constructor copies an existing buffer to read from. * * \param data The existing buffer * \param length The length of the existing buffer */ MemoryCopyReader(const atUint8* data, atUint64 length); /*! \brief This constructor creates an instance from a file on disk. * * \param filename The file to create the stream from */ MemoryCopyReader(const std::string& filename) : MemoryReader(NULL, 0), m_filepath(filename) {loadData();} void setData(const atUint8* data, atUint64 length); protected: void loadData(); std::unique_ptr m_dataCopy; std::string m_filepath; //!< Path to the target file }; } // io } // Athena #ifndef MEMORYREADER_BASE #define MEMORYREADER_BASE() \ private: \ typedef Athena::io::MemoryReader base #endif // MEMORYREADER_BASE #ifndef MEMORYCOPYREADER_BASE #define MEMORYCOPYREADER_BASE() \ private: \ typedef Athena::io::MemoryCopyReader base #endif // MEMORYCOPYREADER_BASE #endif // MEMORYREADER_HPP