EBIKE-FreeRTOS/Common/ethernet/lwIP/include/lwip/pbuf.h
2024-04-14 18:38:39 +08:00

114 lines
3.8 KiB
C

/*
* Copyright (c) 2001-2004 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. The name of the author may not be used to endorse or promote products
* derived from this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``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 AUTHOR 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 lwIP TCP/IP stack.
*
* Author: Adam Dunkels <adam@sics.se>
*
*/
#ifndef __LWIP_PBUF_H__
#define __LWIP_PBUF_H__
#include "arch/cc.h"
#define PBUF_TRANSPORT_HLEN 20
#define PBUF_IP_HLEN 20
typedef enum {
PBUF_TRANSPORT,
PBUF_IP,
PBUF_LINK,
PBUF_RAW
} pbuf_layer;
typedef enum {
PBUF_RAM,
PBUF_ROM,
PBUF_REF,
PBUF_POOL
} pbuf_flag;
/* Definitions for the pbuf flag field. These are NOT the flags that
* are passed to pbuf_alloc(). */
#define PBUF_FLAG_RAM 0x00U /* Flags that pbuf data is stored in RAM */
#define PBUF_FLAG_ROM 0x01U /* Flags that pbuf data is stored in ROM */
#define PBUF_FLAG_POOL 0x02U /* Flags that the pbuf comes from the pbuf pool */
#define PBUF_FLAG_REF 0x04U /* Flags thet the pbuf payload refers to RAM */
/** indicates this packet was broadcast on the link */
#define PBUF_FLAG_LINK_BROADCAST 0x80U
struct pbuf {
/** next pbuf in singly linked pbuf chain */
struct pbuf *next;
/** pointer to the actual data in the buffer */
void *payload;
/**
* total length of this buffer and all next buffers in chain
* belonging to the same packet.
*
* For non-queue packet chains this is the invariant:
* p->tot_len == p->len + (p->next? p->next->tot_len: 0)
*/
u16_t tot_len;
/** length of this buffer */
u16_t len;
/** flags telling the type of pbuf, see PBUF_FLAG_ */
u16_t flags;
/**
* the reference count always equals the number of pointers
* that refer to this pbuf. This can be pointers from an application,
* the stack itself, or pbuf->next pointers from a chain.
*/
u16_t ref;
};
void pbuf_init(void);
struct pbuf *pbuf_alloc(pbuf_layer l, u16_t size, pbuf_flag flag);
void pbuf_realloc(struct pbuf *p, u16_t size);
u8_t pbuf_header(struct pbuf *p, s16_t header_size);
void pbuf_ref(struct pbuf *p);
void pbuf_ref_chain(struct pbuf *p);
u8_t pbuf_free(struct pbuf *p);
u8_t pbuf_clen(struct pbuf *p);
void pbuf_cat(struct pbuf *h, struct pbuf *t);
void pbuf_chain(struct pbuf *h, struct pbuf *t);
struct pbuf *pbuf_take(struct pbuf *f);
struct pbuf *pbuf_dechain(struct pbuf *p);
void pbuf_queue(struct pbuf *p, struct pbuf *n);
struct pbuf * pbuf_dequeue(struct pbuf *p);
#endif /* __LWIP_PBUF_H__ */