netbuf.c File Reference

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

---

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

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

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.

void netbuf_delete

(

struct netbuf *

buf

)

Deallocate a netbuf allocated by netbuf_new().

Parameters:

buf

pointer to a netbuf allocated by netbuf_new()

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

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

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

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

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

---