#include "lwip/opt.h"
#include "lwip/err.h"

Include dependency graph for pbuf.h:

This graph shows which files directly or indirectly include this file:

Classes
struct	pbuf

struct	pbuf_rom

Macros
#define	LWIP_SUPPORT_CUSTOM_PBUF ((IP_FRAG && !LWIP_NETIF_TX_SINGLE_PBUF) \|\| (LWIP_IPV6 && LWIP_IPV6_FRAG))

#define	PBUF_NEEDS_COPY(p) ((p)->type_internal & PBUF_TYPE_FLAG_DATA_VOLATILE)

#define	PBUF_TRANSPORT_HLEN 20

#define	PBUF_IP_HLEN 20

#define	PBUF_TYPE_FLAG_STRUCT_DATA_CONTIGUOUS 0x80

#define	PBUF_TYPE_FLAG_DATA_VOLATILE 0x40

#define	PBUF_TYPE_ALLOC_SRC_MASK 0x0F

#define	PBUF_ALLOC_FLAG_RX 0x0100

#define	PBUF_ALLOC_FLAG_DATA_CONTIGUOUS 0x0200

#define	PBUF_TYPE_ALLOC_SRC_MASK_STD_HEAP 0x00

#define	PBUF_TYPE_ALLOC_SRC_MASK_STD_MEMP_PBUF 0x01

#define	PBUF_TYPE_ALLOC_SRC_MASK_STD_MEMP_PBUF_POOL 0x02

#define	PBUF_TYPE_ALLOC_SRC_MASK_APP_MIN 0x03

#define	PBUF_TYPE_ALLOC_SRC_MASK_APP_MAX PBUF_TYPE_ALLOC_SRC_MASK

#define	PBUF_FLAG_PUSH 0x01U

#define	PBUF_FLAG_IS_CUSTOM 0x02U

#define	PBUF_FLAG_MCASTLOOP 0x04U

#define	PBUF_FLAG_LLBCAST 0x08U

#define	PBUF_FLAG_LLMCAST 0x10U

#define	PBUF_FLAG_TCP_FIN 0x20U

#define	PBUF_POOL_FREE_OOSEQ 1

#define	PBUF_CHECK_FREE_OOSEQ()

#define	pbuf_init()

#define	pbuf_get_allocsrc(p) ((p)->type_internal & PBUF_TYPE_ALLOC_SRC_MASK)

#define	pbuf_match_allocsrc(p, type) (pbuf_get_allocsrc(p) == ((type) & PBUF_TYPE_ALLOC_SRC_MASK))

#define	pbuf_match_type(p, type) pbuf_match_allocsrc(p, type)

Enumerations
enum	pbuf_layer { PBUF_TRANSPORT = PBUF_LINK_ENCAPSULATION_HLEN + PBUF_LINK_HLEN + PBUF_IP_HLEN + PBUF_TRANSPORT_HLEN , PBUF_IP = PBUF_LINK_ENCAPSULATION_HLEN + PBUF_LINK_HLEN + PBUF_IP_HLEN , PBUF_LINK = PBUF_LINK_ENCAPSULATION_HLEN + PBUF_LINK_HLEN , PBUF_RAW_TX = PBUF_LINK_ENCAPSULATION_HLEN , PBUF_RAW = 0 }

enum	pbuf_type { PBUF_RAM = (PBUF_ALLOC_FLAG_DATA_CONTIGUOUS \| PBUF_TYPE_FLAG_STRUCT_DATA_CONTIGUOUS \| PBUF_TYPE_ALLOC_SRC_MASK_STD_HEAP) , PBUF_ROM = PBUF_TYPE_ALLOC_SRC_MASK_STD_MEMP_PBUF , PBUF_REF = (PBUF_TYPE_FLAG_DATA_VOLATILE \| PBUF_TYPE_ALLOC_SRC_MASK_STD_MEMP_PBUF) , PBUF_POOL = (PBUF_ALLOC_FLAG_RX \| PBUF_TYPE_FLAG_STRUCT_DATA_CONTIGUOUS \| PBUF_TYPE_ALLOC_SRC_MASK_STD_MEMP_PBUF_POOL) }

Functions
struct pbuf *	pbuf_alloc (pbuf_layer l, u16_t length, pbuf_type type)

struct pbuf *	pbuf_alloc_reference (void *payload, u16_t length, pbuf_type type)

void	pbuf_realloc (struct pbuf *p, u16_t size)

u8_t	pbuf_header (struct pbuf *p, s16_t header_size)

u8_t	pbuf_header_force (struct pbuf *p, s16_t header_size)

u8_t	pbuf_add_header (struct pbuf *p, size_t header_size_increment)

u8_t	pbuf_add_header_force (struct pbuf *p, size_t header_size_increment)

u8_t	pbuf_remove_header (struct pbuf *p, size_t header_size)

struct pbuf *	pbuf_free_header (struct pbuf *q, u16_t size)

void	pbuf_ref (struct pbuf *p)

u8_t	pbuf_free (struct pbuf *p)

u16_t	pbuf_clen (const 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, const struct pbuf p_from)

err_t	pbuf_copy_partial_pbuf (struct pbuf p_to, const struct pbuf p_from, u16_t copy_len, u16_t offset)

u16_t	pbuf_copy_partial (const struct pbuf p, void dataptr, u16_t len, u16_t offset)

void *	pbuf_get_contiguous (const struct pbuf p, void buffer, size_t bufsize, u16_t len, u16_t offset)

err_t	pbuf_take (struct pbuf buf, const void dataptr, u16_t len)

err_t	pbuf_take_at (struct pbuf buf, const void dataptr, u16_t len, u16_t offset)

struct pbuf *	pbuf_skip (struct pbuf in, u16_t in_offset, u16_t out_offset)

struct pbuf *	pbuf_coalesce (struct pbuf *p, pbuf_layer layer)

struct pbuf *	pbuf_clone (pbuf_layer l, pbuf_type type, struct pbuf *p)

u8_t	pbuf_get_at (const struct pbuf *p, u16_t offset)

int	pbuf_try_get_at (const struct pbuf *p, u16_t offset)

void	pbuf_put_at (struct pbuf *p, u16_t offset, u8_t data)

u16_t	pbuf_memcmp (const struct pbuf p, u16_t offset, const void s2, u16_t n)

u16_t	pbuf_memfind (const struct pbuf p, const void mem, u16_t mem_len, u16_t start_offset)

u16_t	pbuf_strstr (const struct pbuf p, const char substr)

Detailed Description

pbuf API

Definition in file pbuf.h.

Macro Definition Documentation

◆ LWIP_SUPPORT_CUSTOM_PBUF

#define LWIP_SUPPORT_CUSTOM_PBUF ((IP_FRAG && !LWIP_NETIF_TX_SINGLE_PBUF) || (LWIP_IPV6 && LWIP_IPV6_FRAG))

LWIP_SUPPORT_CUSTOM_PBUF==1: Custom pbufs behave much like their pbuf type but they are allocated by external code (initialised by calling pbuf_alloced_custom()) and when pbuf_free gives up their last reference, they are freed by calling pbuf_custom->custom_free_function(). Currently, the pbuf_custom code is only needed for one specific configuration of IP_FRAG, unless required by external driver/application code.

Definition at line 55 of file pbuf.h.

◆ PBUF_ALLOC_FLAG_DATA_CONTIGUOUS

#define PBUF_ALLOC_FLAG_DATA_CONTIGUOUS 0x0200

Indicates the application needs the pbuf payload to be in one piece

Definition at line 131 of file pbuf.h.

◆ PBUF_ALLOC_FLAG_RX

#define PBUF_ALLOC_FLAG_RX 0x0100

Indicates this pbuf is used for RX (if not set, indicates use for TX). This information can be used to keep some spare RX buffers e.g. for receiving TCP ACKs to unblock a connection)

Definition at line 129 of file pbuf.h.

◆ PBUF_CHECK_FREE_OOSEQ

#define PBUF_CHECK_FREE_OOSEQ ( )

Definition at line 269 of file pbuf.h.

◆ PBUF_FLAG_IS_CUSTOM

#define PBUF_FLAG_IS_CUSTOM 0x02U

indicates this is a custom pbuf: pbuf_free calls pbuf_custom->custom_free_function() when the last reference is released (plus custom PBUF_RAM cannot be trimmed)

Definition at line 175 of file pbuf.h.

◆ PBUF_FLAG_LLBCAST

#define PBUF_FLAG_LLBCAST 0x08U

indicates this pbuf was received as link-level broadcast

Definition at line 179 of file pbuf.h.

◆ PBUF_FLAG_LLMCAST

#define PBUF_FLAG_LLMCAST 0x10U

indicates this pbuf was received as link-level multicast

Definition at line 181 of file pbuf.h.

◆ PBUF_FLAG_MCASTLOOP

#define PBUF_FLAG_MCASTLOOP 0x04U

indicates this pbuf is UDP multicast to be looped back

Definition at line 177 of file pbuf.h.

◆ PBUF_FLAG_PUSH

#define PBUF_FLAG_PUSH 0x01U

indicates this packet's data should be immediately passed to the application

Definition at line 172 of file pbuf.h.

◆ PBUF_FLAG_TCP_FIN

#define PBUF_FLAG_TCP_FIN 0x20U

indicates this pbuf includes a TCP FIN flag

Definition at line 183 of file pbuf.h.

◆ pbuf_get_allocsrc

#define pbuf_get_allocsrc ( p ) ((p)->type_internal & PBUF_TYPE_ALLOC_SRC_MASK)

Definition at line 283 of file pbuf.h.

◆ pbuf_init

#define pbuf_init ( )

Definition at line 273 of file pbuf.h.

◆ PBUF_IP_HLEN

#define PBUF_IP_HLEN 20

Definition at line 82 of file pbuf.h.

◆ pbuf_match_allocsrc

#define pbuf_match_allocsrc	(	p,
		type
	)	(pbuf_get_allocsrc(p) == ((type) & PBUF_TYPE_ALLOC_SRC_MASK))

Definition at line 284 of file pbuf.h.

◆ pbuf_match_type

#define pbuf_match_type	(	p,
		type
	)	pbuf_match_allocsrc(p, type)

Definition at line 285 of file pbuf.h.

◆ PBUF_POOL_FREE_OOSEQ

#define PBUF_POOL_FREE_OOSEQ 1

Define this to 0 to prevent freeing ooseq pbufs when the PBUF_POOL is empty

Definition at line 255 of file pbuf.h.

◆ PBUF_TRANSPORT_HLEN

#define PBUF_TRANSPORT_HLEN 20

Definition at line 78 of file pbuf.h.

◆ PBUF_TYPE_ALLOC_SRC_MASK

#define PBUF_TYPE_ALLOC_SRC_MASK 0x0F

4 bits are reserved for 16 allocation sources (e.g. heap, pool1, pool2, etc) Internally, we use: 0=heap, 1=MEMP_PBUF, 2=MEMP_PBUF_POOL -> 13 types free

Definition at line 125 of file pbuf.h.

◆ PBUF_TYPE_ALLOC_SRC_MASK_APP_MAX

#define PBUF_TYPE_ALLOC_SRC_MASK_APP_MAX PBUF_TYPE_ALLOC_SRC_MASK

Last pbuf allocation type for applications

Definition at line 139 of file pbuf.h.

◆ PBUF_TYPE_ALLOC_SRC_MASK_APP_MIN

#define PBUF_TYPE_ALLOC_SRC_MASK_APP_MIN 0x03

First pbuf allocation type for applications

Definition at line 137 of file pbuf.h.

◆ PBUF_TYPE_ALLOC_SRC_MASK_STD_HEAP

#define PBUF_TYPE_ALLOC_SRC_MASK_STD_HEAP 0x00

Definition at line 133 of file pbuf.h.

◆ PBUF_TYPE_ALLOC_SRC_MASK_STD_MEMP_PBUF

#define PBUF_TYPE_ALLOC_SRC_MASK_STD_MEMP_PBUF 0x01

Definition at line 134 of file pbuf.h.

◆ PBUF_TYPE_ALLOC_SRC_MASK_STD_MEMP_PBUF_POOL

#define PBUF_TYPE_ALLOC_SRC_MASK_STD_MEMP_PBUF_POOL 0x02

Definition at line 135 of file pbuf.h.

◆ PBUF_TYPE_FLAG_DATA_VOLATILE

#define PBUF_TYPE_FLAG_DATA_VOLATILE 0x40

Indicates the data stored in this pbuf can change. If this pbuf needs to be queued, it must be copied/duplicated.

Definition at line 122 of file pbuf.h.

◆ PBUF_TYPE_FLAG_STRUCT_DATA_CONTIGUOUS

#define PBUF_TYPE_FLAG_STRUCT_DATA_CONTIGUOUS 0x80

Indicates that the payload directly follows the struct pbuf. This makes pbuf_header work in both directions.

Definition at line 119 of file pbuf.h.

Function Documentation

◆ pbuf_add_header()

u8_t pbuf_add_header	(	struct pbuf *	p,
		size_t	header_size_increment
	)

Adjusts the payload pointer to reveal headers in the payload.

Adjusts the ->payload pointer so that space for a header appears in the pbuf payload.

The ->payload, ->tot_len and ->len fields are adjusted.

Parameters

p	pbuf to change the header size.
header_size_increment	Number of bytes to increment header size which increases the size of the pbuf. New space is on the front. If header_size_increment is 0, this function does nothing and returns successful.

PBUF_ROM and PBUF_REF type buffers cannot have their sizes increased, so the call will fail. A check is made that the increase in header size does not move the payload pointer in front of the start of the buffer.

Returns: non-zero on failure, zero on success.

Definition at line 554 of file pbuf.c.

{
  return pbuf_add_header_impl(p, header_size_increment, 0);
}

Referenced by test_udp_create_test_packet().

◆ pbuf_add_header_force()

u8_t pbuf_add_header_force	(	struct pbuf *	p,
		size_t	header_size_increment
	)

Same as pbuf_add_header but does not check if 'header_size > 0' is allowed. This is used internally only, to allow PBUF_REF for RX.

Definition at line 564 of file pbuf.c.

{
  return pbuf_add_header_impl(p, header_size_increment, 1);
}

◆ pbuf_clen()

u16_t pbuf_clen ( const struct pbuf * p )

Count number of pbufs in a chain

Parameters

p	first pbuf of chain

Returns: the number of pbufs in a chain

Definition at line 811 of file pbuf.c.

{
  u16_t len;
 
  len = 0;
  while (p != NULL) {
    ++len;
    p = p->next;
  }
  return len;
}

◆ pbuf_dechain()

struct pbuf * pbuf_dechain ( struct pbuf * p )

Dechains the first pbuf from its succeeding pbufs in the chain.

Makes p->tot_len field equal to p->len.

Parameters

p	pbuf to dechain

Returns: remainder of the pbuf chain, or NULL if it was de-allocated.

Note: May not be called on a packet queue.

Definition at line 914 of file pbuf.c.

{
  struct pbuf *q;
  u8_t tail_gone = 1;
  /* tail */
  q = p->next;
  /* pbuf has successor in chain? */
  if (q != NULL) {
    /* assert tot_len invariant: (p->tot_len == p->len + (p->next? p->next->tot_len: 0) */
    LWIP_ASSERT("p->tot_len == p->len + q->tot_len", q->tot_len == p->tot_len - p->len);
    /* enforce invariant if assertion is disabled */
    q->tot_len = (u16_t)(p->tot_len - p->len);
    /* decouple pbuf from remainder */
    p->next = NULL;
    /* total length of pbuf p is its own length only */
    p->tot_len = p->len;
    /* q is no longer referenced by p, free it */
    LWIP_DEBUGF(PBUF_DEBUG | LWIP_DBG_TRACE, ("pbuf_dechain: unreferencing %p\n", (void *)q));
    tail_gone = pbuf_free(q);
    if (tail_gone > 0) {
      LWIP_DEBUGF(PBUF_DEBUG | LWIP_DBG_TRACE,
                  ("pbuf_dechain: deallocated %p (as it is no longer referenced)\n", (void *)q));
    }
    /* return remaining tail or NULL if deallocated */
  }
  /* assert tot_len invariant: (p->tot_len == p->len + (p->next? p->next->tot_len: 0) */
  LWIP_ASSERT("p->tot_len == p->len", p->tot_len == p->len);
  return ((tail_gone > 0) ? NULL : q);
}

◆ pbuf_free_header()

struct pbuf * pbuf_free_header	(	struct pbuf *	q,
		u16_t	size
	)

Similar to pbuf_header(-size) but de-refs header pbufs for (size >= p->len)

Parameters

q	pbufs to operate on
size	The number of bytes to remove from the beginning of the pbuf list. While size >= p->len, pbufs are freed. ATTENTION: this is the opposite direction as pbuf_header, but takes an u16_t not s16_t!

Returns: the new head pbuf

Definition at line 674 of file pbuf.c.

{
  struct pbuf *p = q;
  u16_t free_left = size;
  while (free_left && p) {
    if (free_left >= p->len) {
      struct pbuf *f = p;
      free_left = (u16_t)(free_left - p->len);
      p = p->next;
      f->next = NULL;
      pbuf_free(f);
    } else {
      pbuf_remove_header(p, free_left);
      free_left = 0;
    }
  }
  return p;
}

◆ pbuf_header()

u8_t pbuf_header	(	struct pbuf *	p,
		s16_t	header_size_increment
	)

Adjusts the payload pointer to hide or reveal headers in the payload.

Adjusts the ->payload pointer so that space for a header (dis)appears in the pbuf payload.

The ->payload, ->tot_len and ->len fields are adjusted.

Parameters

p	pbuf to change the header size.
header_size_increment	Number of bytes to increment header size which increases the size of the pbuf. New space is on the front. (Using a negative value decreases the header size.) If header_size_increment is 0, this function does nothing and returns successful.

PBUF_ROM and PBUF_REF type buffers cannot have their sizes increased, so the call will fail. A check is made that the increase in header size does not move the payload pointer in front of the start of the buffer.

Returns: non-zero on failure, zero on success.

Definition at line 649 of file pbuf.c.

{
  return pbuf_header_impl(p, header_size_increment, 0);
}

Referenced by START_TEST(), tcp_create_segment_wnd(), and test_tcp_input().

◆ pbuf_header_force()

u8_t pbuf_header_force	(	struct pbuf *	p,
		s16_t	header_size_increment
	)

Same as pbuf_header but does not check if 'header_size > 0' is allowed. This is used internally only, to allow PBUF_REF for RX.

Definition at line 659 of file pbuf.c.

{
  return pbuf_header_impl(p, header_size_increment, 1);
}

◆ pbuf_remove_header()

u8_t pbuf_remove_header	(	struct pbuf *	p,
		size_t	header_size_decrement
	)

Adjusts the payload pointer to hide headers in the payload.

Adjusts the ->payload pointer so that space for a header disappears in the pbuf payload.

The ->payload, ->tot_len and ->len fields are adjusted.

Parameters

p	pbuf to change the header size.
header_size_decrement	Number of bytes to decrement header size which decreases the size of the pbuf. If header_size_decrement is 0, this function does nothing and returns successful.

Returns: non-zero on failure, zero on success.

Definition at line 585 of file pbuf.c.

{
  void *payload;
  u16_t increment_magnitude;
 
  LWIP_ASSERT("p != NULL", p != NULL);
  if ((p == NULL) || (header_size_decrement > 0xFFFF)) {
    return 1;
  }
  if (header_size_decrement == 0) {
    return 0;
  }
 
  increment_magnitude = (u16_t)header_size_decrement;
  /* Check that we aren't going to move off the end of the pbuf */
  LWIP_ERROR("increment_magnitude <= p->len", (increment_magnitude <= p->len), return 1;);
 
  /* remember current payload pointer */
  payload = p->payload;
  LWIP_UNUSED_ARG(payload); /* only used in LWIP_DEBUGF below */
 
  /* increase payload pointer (guarded by length check above) */
  p->payload = (u8_t *)p->payload + header_size_decrement;
  /* modify pbuf length fields */
  p->len = (u16_t)(p->len - increment_magnitude);
  p->tot_len = (u16_t)(p->tot_len - increment_magnitude);
 
  LWIP_DEBUGF(PBUF_DEBUG | LWIP_DBG_TRACE, ("pbuf_remove_header: old %p new %p (%"U16_F")\n",
              (void *)payload, (void *)p->payload, increment_magnitude));
 
  return 0;
}

Referenced by pbuf_free_header(), and pbuf_header_impl().

◆ pbuf_strstr()

u16_t pbuf_strstr	(	const struct pbuf *	p,
		const char *	substr
	)

Find occurrence of substr with length substr_len in pbuf p, start at offset start_offset WARNING: in contrast to strstr(), this one does not stop at the first \0 in the pbuf/source string!

Parameters

p	pbuf to search, maximum length is 0xFFFE since 0xFFFF is used as return value 'not found'
substr	string to search for in p, maximum length is 0xFFFE

Returns: 0xFFFF if substr was not found in p or the index where it was found

Definition at line 1534 of file pbuf.c.

{
  size_t substr_len;
  if ((substr == NULL) || (substr[0] == 0) || (p->tot_len == 0xFFFF)) {
    return 0xFFFF;
  }
  substr_len = strlen(substr);
  if (substr_len >= 0xFFFF) {
    return 0xFFFF;
  }
  return pbuf_memfind(p, substr, (u16_t)substr_len, 0);
}

Classes

Macros

Enumerations

Functions

Detailed Description

Macro Definition Documentation

◆ LWIP_SUPPORT_CUSTOM_PBUF

◆ PBUF_ALLOC_FLAG_DATA_CONTIGUOUS

◆ PBUF_ALLOC_FLAG_RX

◆ PBUF_CHECK_FREE_OOSEQ

◆ PBUF_FLAG_IS_CUSTOM

◆ PBUF_FLAG_LLBCAST

◆ PBUF_FLAG_LLMCAST

◆ PBUF_FLAG_MCASTLOOP

◆ PBUF_FLAG_PUSH

◆ PBUF_FLAG_TCP_FIN

◆ pbuf_get_allocsrc

◆ pbuf_init

◆ PBUF_IP_HLEN

◆ pbuf_match_allocsrc

◆ pbuf_match_type

◆ PBUF_POOL_FREE_OOSEQ

◆ PBUF_TRANSPORT_HLEN

◆ PBUF_TYPE_ALLOC_SRC_MASK

◆ PBUF_TYPE_ALLOC_SRC_MASK_APP_MAX

◆ PBUF_TYPE_ALLOC_SRC_MASK_APP_MIN

◆ PBUF_TYPE_ALLOC_SRC_MASK_STD_HEAP

◆ PBUF_TYPE_ALLOC_SRC_MASK_STD_MEMP_PBUF

◆ PBUF_TYPE_ALLOC_SRC_MASK_STD_MEMP_PBUF_POOL

◆ PBUF_TYPE_FLAG_DATA_VOLATILE

◆ PBUF_TYPE_FLAG_STRUCT_DATA_CONTIGUOUS

Function Documentation

◆ pbuf_add_header()

◆ pbuf_add_header_force()

◆ pbuf_clen()

◆ pbuf_dechain()

◆ pbuf_free_header()

◆ pbuf_header()

◆ pbuf_header_force()

◆ pbuf_remove_header()

◆ pbuf_strstr()