osd-contiki/core/net/rime/rimebuf.h

303 lines
11 KiB
C

/**
* \addtogroup rime
* @{
*/
/**
* \defgroup rimebuf Rime buffer management
* @{
*
* The rimebuf module does Rime's buffer management.
*/
/*
* Copyright (c) 2006, Swedish Institute of Computer Science.
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. Neither the name of the Institute nor the names of its contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE INSTITUTE AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE INSTITUTE OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*
* This file is part of the Contiki operating system.
*
* $Id: rimebuf.h,v 1.11 2007/11/17 18:05:21 adamdunkels Exp $
*/
/**
* \file
* Header file for the Rime buffer (rimebuf) management
* \author
* Adam Dunkels <adam@sics.se>
*/
#ifndef __RIMEBUF_H__
#define __RIMEBUF_H__
#include "contiki-conf.h"
/**
* \brief The size of the rimebuf, in bytes
*/
#ifdef RIMEBUF_CONF_SIZE
#define RIMEBUF_SIZE RIMEBUF_CONF_SIZE
#else
#define RIMEBUF_SIZE 128
#endif
/**
* \brief The size of the rimebuf header, in bytes
*/
#ifdef RIMEBUF_CONF_HDR_SIZE
#define RIMEBUF_HDR_SIZE RIMEBUF_CONF_HDR_SIZE
#else
#define RIMEBUF_HDR_SIZE 32
#endif
/**
* \brief Clear and reset the rimebuf
*
* This function clears the rimebuf and resets all
* internal state pointers (header size, header pointer,
* external data pointer). It is used before preparing a
* packet in the rimebuf.
*
*/
void rimebuf_clear(void);
/**
* \brief Get a pointer to the data in the rimebuf
* \return Pointer to the rimebuf data
*
* This function is used to get a pointer to the data in
* the rimebuf. The data is either stored in the rimebuf,
* or referenced to an external location.
*
* For outbound packets, the rimebuf consists of two
* parts: header and data. The header is accessed with the
* rimebuf_hdrptr() function.
*
* For incoming packets, both the packet header and the
* packet data is stored in the data portion of the
* rimebuf. Thus this function is used to get a pointer to
* the header for incoming packets.
*
*/
void *rimebuf_dataptr(void);
/**
* \brief Get a pointer to the header in the rimebuf, for outbound packets
* \return Pointer to the rimebuf header
*
* For outbound packets, the rimebuf consists of two
* parts: header and data. This function is used to get a
* pointer to the header in the rimebuf. The header is
* stored in the rimebuf.
*
*/
void *rimebuf_hdrptr(void);
/**
* \brief Get the length of the header in the rimebuf, for outbound packets
* \return Length of the header in the rimebuf
*
* For outbound packets, the rimebuf consists of two
* parts: header and data. This function is used to get
* the length of the header in the rimebuf. The header is
* stored in the rimebuf and accessed via the
* rimebuf_hdrptr() function.
*
*/
u8_t rimebuf_hdrlen(void);
/**
* \brief Get the length of the data in the rimebuf
* \return Length of the data in the rimebuf
*
* For outbound packets, the rimebuf consists of two
* parts: header and data. This function is used to get
* the length of the data in the rimebuf. The data is
* stored in the rimebuf and accessed via the
* rimebuf_dataptr() function.
*
* For incoming packets, both the packet header and the
* packet data is stored in the data portion of the
* rimebuf. This function is then used to get the total
* length of the packet - both header and data.
*
*/
u16_t rimebuf_datalen(void);
/**
* \brief Get the total length of the header and data in the rimebuf
* \return Length of data and header in the rimebuf
*
*/
u16_t rimebuf_totlen(void);
/**
* \brief Set the length of the data in the rimebuf
* \param len The length of the data
*
* For outbound packets, the rimebuf consists of two
* parts: header and data. This function is used to set
* the length of the data in the rimebuf.
*/
void rimebuf_set_datalen(u16_t len);
/**
* \brief Point the rimebuf to external data
* \param ptr A pointer to the external data
* \param len The length of the external data
*
* For outbound packets, the rimebuf consists of two
* parts: header and data. This function is used to make
* the rimebuf point to external data. The function also
* specifies the length of the external data that the
* rimebuf references.
*/
void rimebuf_reference(void *ptr, u16_t len);
/**
* \brief Check if the rimebuf references external data
* \retval Non-zero if the rimebuf references external data, zero otherwise.
*
* For outbound packets, the rimebuf consists of two
* parts: header and data. This function is used to check
* if the rimebuf points to external data that has
* previously been referenced with rimebuf_reference().
*
*/
int rimebuf_is_reference(void);
/**
* \brief Get a pointer to external data referenced by the rimebuf
* \retval A pointer to the external data
*
* For outbound packets, the rimebuf consists of two
* parts: header and data. The data may point to external
* data that has previously been referenced with
* rimebuf_reference(). This function is used to get a
* pointer to the external data.
*
*/
void *rimebuf_reference_ptr(void);
/**
* \brief Compact the rimebuf
*
* This function compacts the rimebuf by copying the data
* portion of the rimebuf so that becomes consecutive to
* the header. It also copies external data that has
* previously been referenced with rimebuf_reference()
* into the rimebuf.
*
* This function is called by the Rime code before a
* packet is to be sent by a device driver. This assures
* that the entire packet is consecutive in memory.
*
*/
void rimebuf_compact(void);
/**
* \brief Copy from external data into the rimebuf
* \param from A pointer to the data from which to copy
* \param len The size of the data to copy
* \retval The number of bytes that was copied into the rimebuf
*
* This function copies data from a pointer into the
* rimebuf. If the data that is to be copied is larger
* than the rimebuf, only the data that fits in the
* rimebuf is copied. The number of bytes that could be
* copied into the rimbuf is returned.
*
*/
int rimebuf_copyfrom(const void *from, u16_t len);
/**
* \brief Copy the entire rimebuf to an external buffer
* \param to A pointer to the buffer to which the data is to be copied
* \retval The number of bytes that was copied to the external buffer
*
* This function copies the rimebuf to an external
* buffer. Both the data portion and the header portion of
* the rimebuf is copied. If the rimebuf referenced
* external data (referenced with rimebuf_reference()) the
* external data is copied.
*
* The external buffer to which the rimebuf is to be
* copied must be able to accomodate at least
* (RIMEBUF_SIZE + RIMEBUF_HDR_SIZE) bytes. The number of
* bytes that was copied to the external buffer is
* returned.
*
*/
int rimebuf_copyto(void *to);
/**
* \brief Copy the header portion of the rimebuf to an external buffer
* \param to A pointer to the buffer to which the data is to be copied
* \retval The number of bytes that was copied to the external buffer
*
* This function copies the header portion of the rimebuf
* to an external buffer.
*
* The external buffer to which the rimebuf is to be
* copied must be able to accomodate at least
* RIMEBUF_HDR_SIZE bytes. The number of bytes that was
* copied to the external buffer is returned.
*
*/
int rimebuf_copyto_hdr(u8_t *to);
/**
* \brief Extend the header of the rimebuf, for outbound packets
* \param size The number of bytes the header should be extended
* \retval Non-zero if the header could be extended, zero otherwise
*
* This function is used to allocate extra space in the
* header portion in the rimebuf, when preparing outbound
* packets for transmission. If the function is unable to
* allocate sufficient header space, the function returns
* zero and does not allocate anything.
*
*/
int rimebuf_hdralloc(int size);
/**
* \brief Reduce the header in the rimebuf, for incoming packets
* \param size The number of bytes the header should be reduced
* \retval Non-zero if the header could be reduced, zero otherwise
*
* This function is used to remove the first part of the
* header in the rimebuf, when processing incoming
* packets. If the function is unable to remove the
* requested amount of header space, the function returns
* zero and does not allocate anything.
*
*/
int rimebuf_hdrreduce(int size);
#endif /* __RIMEBUF_H__ */
/** @} */
/** @} */