minix/lib/liblwip/include/lwip/pbuf.h

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/*
* 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 "lwip/opt.h"
#include "lwip/err.h"
#ifdef __cplusplus
extern "C" {
#endif
/** Currently, the pbuf_custom code is only needed for one specific configuration
* of IP_FRAG */
#define LWIP_SUPPORT_CUSTOM_PBUF (IP_FRAG && !IP_FRAG_USES_STATIC_BUF && !LWIP_NETIF_TX_SINGLE_PBUF)
#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 data is stored in RAM */
PBUF_ROM, /* pbuf data is stored in ROM */
PBUF_REF, /* pbuf comes from the pbuf pool */
PBUF_POOL /* pbuf payload refers to RAM */
} pbuf_type;
/** indicates this packet's data should be immediately passed to the application */
#define PBUF_FLAG_PUSH 0x01U
/** indicates this is a custom pbuf: pbuf_free and pbuf_header handle such a
a pbuf differently */
#define PBUF_FLAG_IS_CUSTOM 0x02U
/** indicates this pbuf is UDP multicast to be looped back */
#define PBUF_FLAG_MCASTLOOP 0x04U
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;
/** pbuf_type as u8_t instead of enum to save space */
u8_t /*pbuf_type*/ type;
/** misc flags */
u8_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;
};
#if LWIP_SUPPORT_CUSTOM_PBUF
/** Prototype for a function to free a custom pbuf */
typedef void (*pbuf_free_custom_fn)(struct pbuf *p);
/** A custom pbuf: like a pbuf, but following a function pointer to free it. */
struct pbuf_custom {
/** The actual pbuf */
struct pbuf pbuf;
/** This function is called when pbuf_free deallocates this pbuf(_custom) */
pbuf_free_custom_fn custom_free_function;
};
#endif /* LWIP_SUPPORT_CUSTOM_PBUF */
/* Initializes the pbuf module. This call is empty for now, but may not be in future. */
#define pbuf_init()
struct pbuf *pbuf_alloc(pbuf_layer l, u16_t length, pbuf_type type);
#if LWIP_SUPPORT_CUSTOM_PBUF
struct pbuf *pbuf_alloced_custom(pbuf_layer l, u16_t length, pbuf_type type,
struct pbuf_custom *p, void *payload_mem,
u16_t payload_mem_len);
#endif /* LWIP_SUPPORT_CUSTOM_PBUF */
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);
u8_t pbuf_free(struct pbuf *p);
u8_t pbuf_clen(struct pbuf *p);
void pbuf_cat(struct pbuf *head, struct pbuf *tail);
void pbuf_chain(struct pbuf *head, struct pbuf *tail);
struct pbuf *pbuf_dechain(struct pbuf *p);
err_t pbuf_copy(struct pbuf *p_to, struct pbuf *p_from);
u16_t pbuf_copy_partial(struct pbuf *p, void *dataptr, u16_t len, u16_t offset);
err_t pbuf_take(struct pbuf *buf, const void *dataptr, u16_t len);
struct pbuf *pbuf_coalesce(struct pbuf *p, pbuf_layer layer);
#if LWIP_CHECKSUM_ON_COPY
err_t pbuf_fill_chksum(struct pbuf *p, u16_t start_offset, const void *dataptr,
u16_t len, u16_t *chksum);
#endif /* LWIP_CHECKSUM_ON_COPY */
u8_t pbuf_get_at(struct pbuf* p, u16_t offset);
u16_t pbuf_memcmp(struct pbuf* p, u16_t offset, const void* s2, u16_t n);
u16_t pbuf_memfind(struct pbuf* p, const void* mem, u16_t mem_len, u16_t start_offset);
u16_t pbuf_strstr(struct pbuf* p, const char* substr);
#ifdef __cplusplus
}
#endif
#endif /* __LWIP_PBUF_H__ */