netbuf.c File Reference

#include "lwip/opt.h"
#include "lwip/netbuf.h"
#include "lwip/memp.h"
#include <string.h>

Go to the source code of this file.

Functions
struct netbuf *	netbuf_new (void)
void	netbuf_delete (struct netbuf *buf)
void *	netbuf_alloc (struct netbuf *buf, u16_t size)
void	netbuf_free (struct netbuf *buf)
err_t	netbuf_ref (struct netbuf *buf, const void *dataptr, u16_t size)
void	netbuf_chain (struct netbuf *head, struct netbuf *tail)
err_t	netbuf_data (struct netbuf *buf, void **dataptr, u16_t *len)
s8_t	netbuf_next (struct netbuf *buf)
void	netbuf_first (struct netbuf *buf)

---

Detailed Description

Network buffer management

Definition in file netbuf.c.

---

Function Documentation

void* netbuf_alloc	(	struct netbuf *	buf,
		u16_t	size
	)

Allocate memory for a packet buffer for a given netbuf.

Parameters:

	buf	the netbuf for which to allocate a packet buffer
	size	the size of the packet buffer to allocate

Returns:

pointer to the allocated memory NULL if no memory could be allocated

Definition at line 102 of file netbuf.c.

Here is the call graph for this function:

void netbuf_chain	(	struct netbuf *	head,
		struct netbuf *	tail
	)

Chain one netbuf to another (

See also:

pbuf_chain)

Parameters:

	head	the first netbuf
	tail	netbuf to chain after head, freed by this function, may not be reference after returning

Definition at line 169 of file netbuf.c.

Here is the call graph for this function:

err_t netbuf_data	(	struct netbuf *	buf,
		void **	dataptr,
		u16_t *	len
	)

Get the data pointer and length of the data inside a netbuf.

Parameters:

	buf	netbuf to get the data from
	dataptr	pointer to a void pointer where to store the data pointer
	len	pointer to an u16_t where the length of the data is stored

Returns:

ERR_OK if the information was retreived, ERR_BUF on error.

Definition at line 188 of file netbuf.c.

void netbuf_delete

(

struct netbuf *

buf

)

Deallocate a netbuf allocated by netbuf_new().

Parameters:

buf

pointer to a netbuf allocated by netbuf_new()

Definition at line 82 of file netbuf.c.

Here is the call graph for this function:

void netbuf_first

(

struct netbuf *

buf

)

Move the current data pointer of a packet buffer contained in a netbuf to the beginning of the packet. The packet buffer itself is not modified.

Parameters:

buf

the netbuf to modify

Definition at line 234 of file netbuf.c.

void netbuf_free

(

struct netbuf *

buf

)

Free the packet buffer included in a netbuf

Parameters:

buf

pointer to the netbuf which contains the packet buffer to free

Definition at line 126 of file netbuf.c.

Here is the call graph for this function:

struct netbuf* netbuf_new

(

void

)

[read]

Create (allocate) and initialize a new netbuf. The netbuf doesn't yet contain a packet buffer!

Returns:

a pointer to a new netbuf NULL on lack of memory

Definition at line 56 of file netbuf.c.

Here is the call graph for this function:

s8_t netbuf_next

(

struct netbuf *

buf

)

Move the current data pointer of a packet buffer contained in a netbuf to the next part. The packet buffer itself is not modified.

Parameters:

buf

the netbuf to modify

Returns:

-1 if there is no next part 1 if moved to the next part but now there is no next part 0 if moved to the next part and there are still more parts

Definition at line 213 of file netbuf.c.

err_t netbuf_ref	(	struct netbuf *	buf,
		const void *	dataptr,
		u16_t	size
	)

Let a netbuf reference existing (non-volatile) data.

Parameters:

	buf	netbuf which should reference the data
	dataptr	pointer to the data to reference
	size	size of the data

Returns:

ERR_OK if data is referenced ERR_MEM if data couldn't be referenced due to lack of memory

Definition at line 145 of file netbuf.c.

Here is the call graph for this function: