public/IDataPack.h

Go to the documentation of this file.

/**
 * vim: set ts=4 :
 * =============================================================================
 * SourceMod
 * Copyright (C) 2004-2008 AlliedModders LLC.  All rights reserved.
 * =============================================================================
 *
 * This program is free software; you can redistribute it and/or modify it under
 * the terms of the GNU General Public License, version 3.0, as published by the
 * Free Software Foundation.
 * 
 * This program is distributed in the hope that it will be useful, but WITHOUT
 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
 * FOR A PARTICULAR PURPOSE.  See the GNU General Public License for more
 * details.
 *
 * You should have received a copy of the GNU General Public License along with
 * this program.  If not, see <http://www.gnu.org/licenses/>.
 *
 * As a special exception, AlliedModders LLC gives you permission to link the
 * code of this program (as well as its derivative works) to "Half-Life 2," the
 * "Source Engine," the "SourcePawn JIT," and any Game MODs that run on software
 * by the Valve Corporation.  You must obey the GNU General Public License in
 * all respects for all other code used.  Additionally, AlliedModders LLC grants
 * this exception to all derivative works.  AlliedModders LLC defines further
 * exceptions, found in LICENSE.txt (as of this writing, version JULY-31-2007),
 * or <http://www.sourcemod.net/license.php>.
 *
 * Version: $Id: IDataPack.h 1964 2008-03-27 04:54:56Z damagedsoul $
 */

#ifndef _INCLUDE_SOURCEMOD_INTERFACE_DATAPACK_H_
#define _INCLUDE_SOURCEMOD_INTERFACE_DATAPACK_H_

#include <sp_vm_api.h>

/**
 * @file IDataPack.h
 * @brief Contains functions for packing data abstractly to/from plugins.  The wrappers
 * for creating these are contained in ISourceMod.h
 */

namespace SourceMod
{
          /**
           * @brief Specifies a data pack that can only be read.
           */
          class IDataReader
          {
          public:
                    /**
                     * @brief Resets the position in the data stream to the beginning.
                     */
                    virtual void Reset() const =0;

                    /**
                     * @brief Retrieves the current stream position.
                     *
                     * @return                              Index into the stream.
                     */
                    virtual size_t GetPosition() const =0;

                    /**
                     * @brief Sets the current stream position.
                     *
                     * @param pos                 Index to set the stream at.
                     * @return                              True if succeeded, false if out of bounds.
                     */
                    virtual bool SetPosition(size_t pos) const =0;

                    /**
                     * @brief Reads one cell from the data stream.
                     *
                     * @return                              A cell read from the current position.
                     */
                    virtual cell_t ReadCell() const =0;

                    /**
                     * @brief Reads one float from the data stream.
                     *
                     * @return                              A float read from the current position.
                     */
                    virtual float ReadFloat() const =0;

                    /**
                     * @brief Returns whether or not a specified number of bytes from the current stream
                     *  position to the end can be read.
                     * 
                     * @param bytes               Number of bytes to simulate reading.
                     * @return                              True if can be read, false otherwise.
                     */
                    virtual bool IsReadable(size_t bytes) const =0;

                    /**
                     * @brief Reads a string from the data stream.
                     *
                     * @param len                 Optional pointer to store the string length.
                     * @return                              Pointer to the string, or NULL if out of bounds.
                     */
                    virtual const char *ReadString(size_t *len) const =0;

                    /**
                     * @brief Reads the current position as a generic address.
                     *
                     * @return                              Pointer to the memory.
                     */
                    virtual void *GetMemory() const =0;

                    /**
                    * @brief Reads the current position as a generic data type.
                    *
                    * @param size                 Optional pointer to store the size of the data type.
                    * @return                     Pointer to the data, or NULL if out of bounds.
                    */
                    virtual void *ReadMemory(size_t *size) const =0;
          };

          /**
           * @brief Specifies a data pack that can only be written.
           */
          class IDataPack : public IDataReader
          {
          public:
                    /**
                    * @brief Resets the used size of the stream back to zero.
                    */
                    virtual void ResetSize() =0;

                    /**
                     * @brief Packs one cell into the data stream.
                     *
                     * @param cell                Cell value to write.
                     */
                    virtual void PackCell(cell_t cell) =0;

                    /**
                     * @brief Packs one float into the data stream.
                     *
                     * @param val                 Float value to write.
                     */
                    virtual void PackFloat(float val) =0;

                    /**
                     * @brief Packs one string into the data stream.
                     * The length is recorded as well for buffer overrun protection.
                     *
                     * @param string    String to write.
                     */
                    virtual void PackString(const char *string) =0;

                    /**
                     * @brief Creates a generic block of memory in the stream.
                     *
                     * Note that the pointer it returns can be invalidated on further
                     * writing, since the stream size may grow.  You may need to double back
                     * and fetch the pointer again.
                     *
                     * @param size                Size of the memory to create in the stream.
                     * @param addr                Optional pointer to store the relocated memory address.
                     * @return                              Current position of the stream beforehand.
                     */
                    virtual size_t CreateMemory(size_t size, void **addr) =0;
          };
}

#endif //_INCLUDE_SOURCEMOD_INTERFACE_DATAPACK_H_

---