OrgZephyr/zephyr
OrgZephyr
/
zephyr
mirror of https://github.com/zephyrproject-rtos/zephyr.git
1
0
Fork 0
Code Issues Releases Wiki Activity
zephyr/include/net/buf.h

1444 lines
46 KiB
C
Raw Blame History

/** @file
* @brief Buffer management.
*/
/*
* Copyright (c) 2015 Intel Corporation
*
* SPDX-License-Identifier: Apache-2.0
*/
#ifndef ZEPHYR_INCLUDE_NET_BUF_H_
#define ZEPHYR_INCLUDE_NET_BUF_H_
#include <stddef.h>
#include <zephyr/types.h>
#include <misc/util.h>
#include <zephyr.h>
#ifdef __cplusplus
extern "C" {
#endif
/**
* @brief Network buffer library
* @defgroup net_buf Network Buffer Library
* @ingroup networking
* @{
*/
/* Alignment needed for various parts of the buffer definition */
#define __net_buf_align __aligned(sizeof(int))
/** @def NET_BUF_SIMPLE_DEFINE
* @brief Define a net_buf_simple stack variable.
*
* This is a helper macro which is used to define a net_buf_simple object
* on the stack.
*
* @param _name Name of the net_buf_simple object.
* @param _size Maximum data storage for the buffer.
*/
#define NET_BUF_SIMPLE_DEFINE(_name, _size) \
u8_t net_buf_data_##_name[_size]; \
struct net_buf_simple _name = { \
.data = net_buf_data_##_name, \
.len = 0, \
.size = _size, \
.__buf = net_buf_data_##_name, \
}
/** @def NET_BUF_SIMPLE_DEFINE_STATIC
* @brief Define a static net_buf_simple variable.
*
* This is a helper macro which is used to define a static net_buf_simple
* object.
*
* @param _name Name of the net_buf_simple object.
* @param _size Maximum data storage for the buffer.
*/
#define NET_BUF_SIMPLE_DEFINE_STATIC(_name, _size) \
static __noinit u8_t net_buf_data_##_name[_size]; \
static struct net_buf_simple _name = { \
.data = net_buf_data_##_name, \
.len = 0, \
.size = _size, \
.__buf = net_buf_data_##_name, \
}
/** @brief Simple network buffer representation.
*
* This is a simpler variant of the net_buf object (in fact net_buf uses
* net_buf_simple internally). It doesn't provide any kind of reference
* counting, user data, dynamic allocation, or in general the ability to
* pass through kernel objects such as FIFOs.
*
* The main use of this is for scenarios where the meta-data of the normal
* net_buf isn't needed and causes too much overhead. This could be e.g.
* when the buffer only needs to be allocated on the stack or when the
* access to and lifetime of the buffer is well controlled and constrained.
*
*/
struct net_buf_simple {
/** Pointer to the start of data in the buffer. */
u8_t *data;
/** Length of the data behind the data pointer. */
u16_t len;
/** Amount of data that this buffer can store. */
u16_t size;
/** Start of the data storage. Not to be accessed directly
* (the data pointer should be used instead).
*/
u8_t *__buf;
};
/** @def NET_BUF_SIMPLE
* @brief Define a net_buf_simple stack variable and get a pointer to it.
*
* This is a helper macro which is used to define a net_buf_simple object on
* the stack and the get a pointer to it as follows:
*
* struct net_buf_simple *my_buf = NET_BUF_SIMPLE(10);
*
* After creating the object it needs to be initialized by calling
* net_buf_simple_init().
*
* @param _size Maximum data storage for the buffer.
*
* @return Pointer to stack-allocated net_buf_simple object.
*/
#define NET_BUF_SIMPLE(_size) \
((struct net_buf_simple *)(&(struct { \
struct net_buf_simple buf; \
u8_t data[_size] __net_buf_align; \
}) { \
.buf.size = _size, \
}))
/** @brief Initialize a net_buf_simple object.
*
* This needs to be called after creating a net_buf_simple object using
* the NET_BUF_SIMPLE macro.
*
* @param buf Buffer to initialize.
* @param reserve_head Headroom to reserve.
*/
static inline void net_buf_simple_init(struct net_buf_simple *buf,
size_t reserve_head)
{
if (!buf->__buf) {
buf->__buf = (u8_t *)buf + sizeof(*buf);
}
buf->data = buf->__buf + reserve_head;
buf->len = 0;
}
/**
* @brief Reset buffer
*
* Reset buffer data so it can be reused for other purposes.
*
* @param buf Buffer to reset.
*/
static inline void net_buf_simple_reset(struct net_buf_simple *buf)
{
buf->len = 0;
buf->data = buf->__buf;
}
/**
* @brief Prepare data to be added at the end of the buffer
*
* Increments the data length of a buffer to account for more data
* at the end.
*
* @param buf Buffer to update.
* @param len Number of bytes to increment the length with.
*
* @return The original tail of the buffer.
*/
void *net_buf_simple_add(struct net_buf_simple *buf, size_t len);
/**
* @brief Copy bytes from memory to the end of the buffer
*
* Copies the given number of bytes to the end of the buffer. Increments the
* data length of the buffer to account for more data at the end.
*
* @param buf Buffer to update.
* @param mem Location of data to be added.
* @param len Length of data to be added
*
* @return The original tail of the buffer.
*/
void *net_buf_simple_add_mem(struct net_buf_simple *buf, const void *mem,
size_t len);
/**
* @brief Add (8-bit) byte at the end of the buffer
*
* Adds a byte at the end of the buffer. Increments the data length of
* the buffer to account for more data at the end.
*
* @param buf Buffer to update.
* @param val byte value to be added.
*
* @return Pointer to the value added
*/
u8_t *net_buf_simple_add_u8(struct net_buf_simple *buf, u8_t val);
/**
* @brief Add 16-bit value at the end of the buffer
*
* Adds 16-bit value in little endian format at the end of buffer.
* Increments the data length of a buffer to account for more data
* at the end.
*
* @param buf Buffer to update.
* @param val 16-bit value to be added.
*/
void net_buf_simple_add_le16(struct net_buf_simple *buf, u16_t val);
/**
* @brief Add 16-bit value at the end of the buffer
*
* Adds 16-bit value in big endian format at the end of buffer.
* Increments the data length of a buffer to account for more data
* at the end.
*
* @param buf Buffer to update.
* @param val 16-bit value to be added.
*/
void net_buf_simple_add_be16(struct net_buf_simple *buf, u16_t val);
/**
* @brief Add 32-bit value at the end of the buffer
*
* Adds 32-bit value in little endian format at the end of buffer.
* Increments the data length of a buffer to account for more data
* at the end.
*
* @param buf Buffer to update.
* @param val 32-bit value to be added.
*/
void net_buf_simple_add_le32(struct net_buf_simple *buf, u32_t val);
/**
* @brief Add 32-bit value at the end of the buffer
*
* Adds 32-bit value in big endian format at the end of buffer.
* Increments the data length of a buffer to account for more data
* at the end.
*
* @param buf Buffer to update.
* @param val 32-bit value to be added.
*/
void net_buf_simple_add_be32(struct net_buf_simple *buf, u32_t val);
/**
* @brief Push data to the beginning of the buffer.
*
* Modifies the data pointer and buffer length to account for more data
* in the beginning of the buffer.
*
* @param buf Buffer to update.
* @param len Number of bytes to add to the beginning.
*
* @return The new beginning of the buffer data.
*/
void *net_buf_simple_push(struct net_buf_simple *buf, size_t len);
/**
* @brief Push 16-bit value to the beginning of the buffer
*
* Adds 16-bit value in little endian format to the beginning of the
* buffer.
*
* @param buf Buffer to update.
* @param val 16-bit value to be pushed to the buffer.
*/
void net_buf_simple_push_le16(struct net_buf_simple *buf, u16_t val);
/**
* @brief Push 16-bit value to the beginning of the buffer
*
* Adds 16-bit value in big endian format to the beginning of the
* buffer.
*
* @param buf Buffer to update.
* @param val 16-bit value to be pushed to the buffer.
*/
void net_buf_simple_push_be16(struct net_buf_simple *buf, u16_t val);
/**
* @brief Push 8-bit value to the beginning of the buffer
*
* Adds 8-bit value the beginning of the buffer.
*
* @param buf Buffer to update.
* @param val 8-bit value to be pushed to the buffer.
*/
void net_buf_simple_push_u8(struct net_buf_simple *buf, u8_t val);
/**
* @brief Remove data from the beginning of the buffer.
*
* Removes data from the beginning of the buffer by modifying the data
* pointer and buffer length.
*
* @param buf Buffer to update.
* @param len Number of bytes to remove.
*
* @return New beginning of the buffer data.
*/
void *net_buf_simple_pull(struct net_buf_simple *buf, size_t len);
/**
* @brief Remove data from the beginning of the buffer.
*
* Removes data from the beginning of the buffer by modifying the data
* pointer and buffer length.
*
* @param buf Buffer to update.
* @param len Number of bytes to remove.
*
* @return Pointer to the old location of the buffer data.
*/
void *net_buf_simple_pull_mem(struct net_buf_simple *buf, size_t len);
/**
* @brief Remove a 8-bit value from the beginning of the buffer
*
* Same idea as with net_buf_simple_pull(), but a helper for operating
* on 8-bit values.
*
* @param buf A valid pointer on a buffer.
*
* @return The 8-bit removed value
*/
u8_t net_buf_simple_pull_u8(struct net_buf_simple *buf);
/**
* @brief Remove and convert 16 bits from the beginning of the buffer.
*
* Same idea as with net_buf_simple_pull(), but a helper for operating
* on 16-bit little endian data.
*
* @param buf A valid pointer on a buffer.
*
* @return 16-bit value converted from little endian to host endian.
*/
u16_t net_buf_simple_pull_le16(struct net_buf_simple *buf);
/**
* @brief Remove and convert 16 bits from the beginning of the buffer.
*
* Same idea as with net_buf_simple_pull(), but a helper for operating
* on 16-bit big endian data.
*
* @param buf A valid pointer on a buffer.
*
* @return 16-bit value converted from big endian to host endian.
*/
u16_t net_buf_simple_pull_be16(struct net_buf_simple *buf);
/**
* @brief Remove and convert 32 bits from the beginning of the buffer.
*
* Same idea as with net_buf_simple_pull(), but a helper for operating
* on 32-bit little endian data.
*
* @param buf A valid pointer on a buffer.
*
* @return 32-bit value converted from little endian to host endian.
*/
u32_t net_buf_simple_pull_le32(struct net_buf_simple *buf);
/**
* @brief Remove and convert 32 bits from the beginning of the buffer.
*
* Same idea as with net_buf_simple_pull(), but a helper for operating
* on 32-bit big endian data.
*
* @param buf A valid pointer on a buffer.
*
* @return 32-bit value converted from big endian to host endian.
*/
u32_t net_buf_simple_pull_be32(struct net_buf_simple *buf);
/**
* @brief Get the tail pointer for a buffer.
*
* Get a pointer to the end of the data in a buffer.
*
* @param buf Buffer.
*
* @return Tail pointer for the buffer.
*/
static inline u8_t *net_buf_simple_tail(struct net_buf_simple *buf)
{
return buf->data + buf->len;
}
/**
* @brief Check buffer headroom.
*
* Check how much free space there is in the beginning of the buffer.
*
* buf A valid pointer on a buffer
*
* @return Number of bytes available in the beginning of the buffer.
*/
size_t net_buf_simple_headroom(struct net_buf_simple *buf);
/**
* @brief Check buffer tailroom.
*
* Check how much free space there is at the end of the buffer.
*
* @param buf A valid pointer on a buffer
*
* @return Number of bytes available at the end of the buffer.
*/
size_t net_buf_simple_tailroom(struct net_buf_simple *buf);
/**
* @brief Parsing state of a buffer.
*
* This is used for temporarily storing the parsing state of a buffer
* while giving control of the parsing to a routine which we don't
* control.
*/
struct net_buf_simple_state {
/** Offset of the data pointer from the beginning of the storage */
u16_t offset;
/** Length of data */
u16_t len;
};
/**
* @brief Save the parsing state of a buffer.
*
* Saves the parsing state of a buffer so it can be restored later.
*
* @param buf Buffer from which the state should be saved.
* @param state Storage for the state.
*/
static inline void net_buf_simple_save(struct net_buf_simple *buf,
struct net_buf_simple_state *state)
{
state->offset = net_buf_simple_headroom(buf);
state->len = buf->len;
}
/**
* @brief Restore the parsing state of a buffer.
*
* Restores the parsing state of a buffer from a state previously stored
* by net_buf_simple_save().
*
* @param buf Buffer to which the state should be restored.
* @param state Stored state.
*/
static inline void net_buf_simple_restore(struct net_buf_simple *buf,
struct net_buf_simple_state *state)
{
buf->data = buf->__buf + state->offset;
buf->len = state->len;
}
/** Flag indicating that the buffer has associated fragments. Only used
* internally by the buffer handling code while the buffer is inside a
* FIFO, meaning this never needs to be explicitly set or unset by the
* net_buf API user. As long as the buffer is outside of a FIFO, i.e.
* in practice always for the user for this API, the buf->frags pointer
* should be used instead.
*/
#define NET_BUF_FRAGS BIT(0)
/** Flag indicating that the buffer's associated data pointer, points to
* externally allocated memory. Therefore once ref goes down to zero, the
* pointed data will not need to be deallocated. This never needs to be
* explicitly set or unet by the net_buf API user. Such net_buf is
* exclusively instantiated via net_buf_alloc_with_data() function.
* Reference count mechanism however will behave the same way, and ref
* count going to 0 will free the net_buf but no the data pointer in it.
*/
#define NET_BUF_EXTERNAL_DATA BIT(1)
/** @brief Network buffer representation.
*
* This struct is used to represent network buffers. Such buffers are
* normally defined through the NET_BUF_POOL_*_DEFINE() APIs and allocated
* using the net_buf_alloc() API.
*/
struct net_buf {
union {
/** Allow placing the buffer into sys_slist_t */
sys_snode_t node;
/** Fragments associated with this buffer. */
struct net_buf *frags;
};
/** Reference count. */
u8_t ref;
/** Bit-field of buffer flags. */
u8_t flags;
/** Where the buffer should go when freed up. */
u8_t pool_id;
/* Union for convenience access to the net_buf_simple members, also
* preserving the old API.
*/
union {
/* The ABI of this struct must match net_buf_simple */
struct {
/** Pointer to the start of data in the buffer. */
u8_t *data;
/** Length of the data behind the data pointer. */
u16_t len;
/** Amount of data that this buffer can store. */
u16_t size;
/** Start of the data storage. Not to be accessed
* directly (the data pointer should be used
* instead).
*/
u8_t *__buf;
};
struct net_buf_simple b;
};
/** System metadata for this buffer. */
u8_t user_data[CONFIG_NET_BUF_USER_DATA_SIZE] __net_buf_align;
};
struct net_buf_data_cb {
u8_t * (*alloc)(struct net_buf *buf, size_t *size, s32_t timeout);
u8_t * (*ref)(struct net_buf *buf, u8_t *data);
void (*unref)(struct net_buf *buf, u8_t *data);
};
struct net_buf_data_alloc {
const struct net_buf_data_cb *cb;
void *alloc_data;
};
struct net_buf_pool {
/** LIFO to place the buffer into when free */
struct k_lifo free;
/** Number of buffers in pool */
const u16_t buf_count;
/** Number of uninitialized buffers */
u16_t uninit_count;
#if defined(CONFIG_NET_BUF_POOL_USAGE)
/** Amount of available buffers in the pool. */
s16_t avail_count;
/** Total size of the pool. */
const u16_t pool_size;
/** Name of the pool. Used when printing pool information. */
const char *name;
#endif /* CONFIG_NET_BUF_POOL_USAGE */
/** Optional destroy callback when buffer is freed. */
void (*const destroy)(struct net_buf *buf);
/** Data allocation handlers. */
const struct net_buf_data_alloc *alloc;
/** Start of buffer storage array */
struct net_buf * const __bufs;
};
#if defined(CONFIG_NET_BUF_POOL_USAGE)
#define NET_BUF_POOL_INITIALIZER(_pool, _alloc, _bufs, _count, _destroy) \
{ \
.alloc = _alloc, \
.free = _K_LIFO_INITIALIZER(_pool.free), \
.__bufs = _bufs, \
.buf_count = _count, \
.uninit_count = _count, \
.avail_count = _count, \
.destroy = _destroy, \
.name = STRINGIFY(_pool), \
}
#else
#define NET_BUF_POOL_INITIALIZER(_pool, _alloc, _bufs, _count, _destroy) \
{ \
.alloc = _alloc, \
.free = _K_LIFO_INITIALIZER(_pool.free), \
.__bufs = _bufs, \
.buf_count = _count, \
.uninit_count = _count, \
.destroy = _destroy, \
}
#endif /* CONFIG_NET_BUF_POOL_USAGE */
extern const struct net_buf_data_alloc net_buf_heap_alloc;
/** @def NET_BUF_POOL_HEAP_DEFINE
* @brief Define a new pool for buffers using the heap for the data.
*
* Defines a net_buf_pool struct and the necessary memory storage (array of
* structs) for the needed amount of buffers. After this, the buffers can be
* accessed from the pool through net_buf_alloc. The pool is defined as a
* static variable, so if it needs to be exported outside the current module
* this needs to happen with the help of a separate pointer rather than an
* extern declaration.
*
* The data payload of the buffers will be allocated from the heap using
* k_malloc, so CONFIG_HEAP_MEM_POOL_SIZE must be set to a positive value.
* This kind of pool does not support blocking on the data allocation, so
* the timeout passed to net_buf_alloc will be always treated as K_NO_WAIT
* when trying to allocate the data. This means that allocation failures,
* i.e. NULL returns, must always be handled cleanly.
*
* If provided with a custom destroy callback, this callback is
* responsible for eventually calling net_buf_destroy() to complete the
* process of returning the buffer to the pool.
*
* @param _name Name of the pool variable.
* @param _count Number of buffers in the pool.
* @param _destroy Optional destroy callback when buffer is freed.
*/
#define NET_BUF_POOL_HEAP_DEFINE(_name, _count, _destroy) \
static struct net_buf net_buf_##_name[_count] __noinit; \
struct net_buf_pool _name __net_buf_align \
__in_section(_net_buf_pool, static, _name) = \
NET_BUF_POOL_INITIALIZER(_name, &net_buf_heap_alloc, \
net_buf_##_name, _count, _destroy)
struct net_buf_pool_fixed {
size_t data_size;
u8_t *data_pool;
};
extern const struct net_buf_data_cb net_buf_fixed_cb;
/** @def NET_BUF_POOL_FIXED_DEFINE
* @brief Define a new pool for buffers based on fixed-size data
*
* Defines a net_buf_pool struct and the necessary memory storage (array of
* structs) for the needed amount of buffers. After this, the buffers can be
* accessed from the pool through net_buf_alloc. The pool is defined as a
* static variable, so if it needs to be exported outside the current module
* this needs to happen with the help of a separate pointer rather than an
* extern declaration.
*
* The data payload of the buffers will be allocated from a byte array
* of fixed sized chunks. This kind of pool does not support blocking on
* the data allocation, so the timeout passed to net_buf_alloc will be
* always treated as K_NO_WAIT when trying to allocate the data. This means
* that allocation failures, i.e. NULL returns, must always be handled
* cleanly.
*
* If provided with a custom destroy callback, this callback is
* responsible for eventually calling net_buf_destroy() to complete the
* process of returning the buffer to the pool.
*
* @param _name Name of the pool variable.
* @param _count Number of buffers in the pool.
* @param _data_size Maximum data payload per buffer.
* @param _destroy Optional destroy callback when buffer is freed.
*/
#define NET_BUF_POOL_FIXED_DEFINE(_name, _count, _data_size, _destroy) \
static struct net_buf net_buf_##_name[_count] __noinit; \
static u8_t __noinit net_buf_data_##_name[_count][_data_size]; \
static const struct net_buf_pool_fixed net_buf_fixed_##_name = { \
.data_size = _data_size, \
.data_pool = (u8_t *)net_buf_data_##_name, \
}; \
static const struct net_buf_data_alloc net_buf_fixed_alloc_##_name = {\
.cb = &net_buf_fixed_cb, \
.alloc_data = (void *)&net_buf_fixed_##_name, \
}; \
struct net_buf_pool _name __net_buf_align \
__in_section(_net_buf_pool, static, _name) = \
NET_BUF_POOL_INITIALIZER(_name, &net_buf_fixed_alloc_##_name, \
net_buf_##_name, _count, _destroy)
extern const struct net_buf_data_cb net_buf_var_cb;
/** @def NET_BUF_POOL_VAR_DEFINE
* @brief Define a new pool for buffers with variable size payloads
*
* Defines a net_buf_pool struct and the necessary memory storage (array of
* structs) for the needed amount of buffers. After this, the buffers can be
* accessed from the pool through net_buf_alloc. The pool is defined as a
* static variable, so if it needs to be exported outside the current module
* this needs to happen with the help of a separate pointer rather than an
* extern declaration.
*
* The data payload of the buffers will be based on a memory pool from which
* variable size payloads may be allocated.
*
* If provided with a custom destroy callback, this callback is
* responsible for eventually calling net_buf_destroy() to complete the
* process of returning the buffer to the pool.
*
* @param _name Name of the pool variable.
* @param _count Number of buffers in the pool.
* @param _data_size Total amount of memory available for data payloads.
* @param _destroy Optional destroy callback when buffer is freed.
*/
#define NET_BUF_POOL_VAR_DEFINE(_name, _count, _data_size, _destroy) \
static struct net_buf _net_buf_##_name[_count] __noinit; \
K_MEM_POOL_DEFINE(net_buf_mem_pool_##_name, 16, _data_size, 1, 4); \
static const struct net_buf_data_alloc net_buf_data_alloc_##_name = { \
.cb = &net_buf_var_cb, \
.alloc_data = &net_buf_mem_pool_##_name, \
}; \
struct net_buf_pool _name __net_buf_align \
__in_section(_net_buf_pool, static, _name) = \
NET_BUF_POOL_INITIALIZER(_name, &net_buf_data_alloc_##_name, \
_net_buf_##_name, _count, _destroy)
/** @def NET_BUF_POOL_DEFINE
* @brief Define a new pool for buffers
*
* Defines a net_buf_pool struct and the necessary memory storage (array of
* structs) for the needed amount of buffers. After this,the buffers can be
* accessed from the pool through net_buf_alloc. The pool is defined as a
* static variable, so if it needs to be exported outside the current module
* this needs to happen with the help of a separate pointer rather than an
* extern declaration.
*
* If provided with a custom destroy callback this callback is
* responsible for eventually calling net_buf_destroy() to complete the
* process of returning the buffer to the pool.
*
* @param _name Name of the pool variable.
* @param _count Number of buffers in the pool.
* @param _size Maximum data size for each buffer.
* @param _ud_size Amount of user data space to reserve.
* @param _destroy Optional destroy callback when buffer is freed.
*/
#define NET_BUF_POOL_DEFINE(_name, _count, _size, _ud_size, _destroy) \
BUILD_ASSERT(_ud_size <= CONFIG_NET_BUF_USER_DATA_SIZE); \
NET_BUF_POOL_FIXED_DEFINE(_name, _count, _size, _destroy)
/**
* @brief Looks up a pool based on its ID.
*
* @param id Pool ID (e.g. from buf->pool_id).
*
* @return Pointer to pool.
*/
struct net_buf_pool *net_buf_pool_get(int id);
/**
* @brief Get a zero-based index for a buffer.
*
* This function will translate a buffer into a zero-based index,
* based on its placement in its buffer pool. This can be useful if you
* want to associate an external array of meta-data contexts with the
* buffers of a pool.
*
* @param buf Network buffer.
*
* @return Zero-based index for the buffer.
*/
int net_buf_id(struct net_buf *buf);
/**
* @brief Allocate a new buffer from a pool.
*
* Allocate a new buffer from a pool.
*
* @param pool Which pool to allocate the buffer from.
* @param timeout Affects the action taken should the pool be empty.
* If K_NO_WAIT, then return immediately. If K_FOREVER, then
* wait as long as necessary. Otherwise, wait up to the specified
* number of milliseconds before timing out. Note that some types
* of data allocators do not support blocking (such as the HEAP
* type). In this case it's still possible for net_buf_alloc() to
* fail (return NULL) even if it was given K_FOREVER.
*
* @return New buffer or NULL if out of buffers.
*/
#if defined(CONFIG_NET_BUF_LOG)
struct net_buf *net_buf_alloc_fixed_debug(struct net_buf_pool *pool,
s32_t timeout, const char *func,
int line);
#define net_buf_alloc_fixed(_pool, _timeout) \
net_buf_alloc_fixed_debug(_pool, _timeout, __func__, __LINE__)
#else
struct net_buf *net_buf_alloc_fixed(struct net_buf_pool *pool, s32_t timeout);
#endif
#define net_buf_alloc(_pool, _timeout) net_buf_alloc_fixed(_pool, _timeout)
/**
* @brief Allocate a new buffer from a pool.
*
* Allocate a new buffer from a pool.
*
* @param pool Which pool to allocate the buffer from.
* @param size Amount of data the buffer must be able to fit.
* @param timeout Affects the action taken should the pool be empty.
* If K_NO_WAIT, then return immediately. If K_FOREVER, then
* wait as long as necessary. Otherwise, wait up to the specified
* number of milliseconds before timing out. Note that some types
* of data allocators do not support blocking (such as the HEAP
* type). In this case it's still possible for net_buf_alloc() to
* fail (return NULL) even if it was given K_FOREVER.
*
* @return New buffer or NULL if out of buffers.
*/
#if defined(CONFIG_NET_BUF_LOG)
struct net_buf *net_buf_alloc_len_debug(struct net_buf_pool *pool, size_t size,
s32_t timeout, const char *func,
int line);
#define net_buf_alloc_len(_pool, _size, _timeout) \
net_buf_alloc_len_debug(_pool, _size, _timeout, __func__, __LINE__)
#else
struct net_buf *net_buf_alloc_len(struct net_buf_pool *pool, size_t size,
s32_t timeout);
#endif
/**
* @brief Allocate a new buffer from a pool but with external data pointer.
*
* Allocate a new buffer from a pool, where the data pointer comes from the
* user and not from the pool.
*
* @param pool Which pool to allocate the buffer from.
* @param data External data pointer
* @param size Amount of data the pointed data buffer if able to fit.
* @param timeout Affects the action taken should the pool be empty.
* If K_NO_WAIT, then return immediately. If K_FOREVER, then
* wait as long as necessary. Otherwise, wait up to the specified
* number of milliseconds before timing out. Note that some types
* of data allocators do not support blocking (such as the HEAP
* type). In this case it's still possible for net_buf_alloc() to
* fail (return NULL) even if it was given K_FOREVER.
*
* @return New buffer or NULL if out of buffers.
*/
#if defined(CONFIG_NET_BUF_LOG)
struct net_buf *net_buf_alloc_with_data_debug(struct net_buf_pool *pool,
void *data, size_t size,
s32_t timeout, const char *func,
int line);
#define net_buf_alloc_with_data(_pool, _data_, _size, _timeout) \
net_buf_alloc_with_data_debug(_pool, _data_, _size, _timeout, \
__func__, __LINE__)
#else
struct net_buf *net_buf_alloc_with_data(struct net_buf_pool *pool,
void *data, size_t size,
s32_t timeout);
#endif
/**
* @brief Get a buffer from a FIFO.
*
* Get buffer from a FIFO.
*
* @param fifo Which FIFO to take the buffer from.
* @param timeout Affects the action taken should the FIFO be empty.
* If K_NO_WAIT, then return immediately. If K_FOREVER, then wait as
* long as necessary. Otherwise, wait up to the specified number of
* milliseconds before timing out.
*
* @return New buffer or NULL if the FIFO is empty.
*/
#if defined(CONFIG_NET_BUF_LOG)
struct net_buf *net_buf_get_debug(struct k_fifo *fifo, s32_t timeout,
const char *func, int line);
#define net_buf_get(_fifo, _timeout) \
net_buf_get_debug(_fifo, _timeout, __func__, __LINE__)
#else
struct net_buf *net_buf_get(struct k_fifo *fifo, s32_t timeout);
#endif
/**
* @brief Destroy buffer from custom destroy callback
*
* This helper is only intended to be used from custom destroy callbacks.
* If no custom destroy callback is given to NET_BUF_POOL_*_DEFINE() then
* there is no need to use this API.
*
* @param buf Buffer to destroy.
*/
static inline void net_buf_destroy(struct net_buf *buf)
{
struct net_buf_pool *pool = net_buf_pool_get(buf->pool_id);
k_lifo_put(&pool->free, buf);
}
/**
* @brief Reset buffer
*
* Reset buffer data and flags so it can be reused for other purposes.
*
* @param buf Buffer to reset.
*/
void net_buf_reset(struct net_buf *buf);
/**
* @brief Initialize buffer with the given headroom.
*
* Initializes a buffer with a given headroom. The buffer is not expected to
* contain any data when this API is called.
*
* @param buf Buffer to initialize.
* @param reserve How much headroom to reserve.
*/
void net_buf_simple_reserve(struct net_buf_simple *buf, size_t reserve);
/**
* @brief Put a buffer into a list
*
* Put a buffer to the end of a list. If the buffer contains follow-up
* fragments this function will take care of inserting them as well
* into the list.
*
* @param list Which list to append the buffer to.
* @param buf Buffer.
*/
void net_buf_slist_put(sys_slist_t *list, struct net_buf *buf);
/**
* @brief Get a buffer from a list.
*
* Get buffer from a list. If the buffer had any fragments, these will
* automatically be recovered from the list as well and be placed to
* the buffer's fragment list.
*
* @param list Which list to take the buffer from.
*
* @return New buffer or NULL if the FIFO is empty.
*/
struct net_buf *net_buf_slist_get(sys_slist_t *list);
/**
* @brief Put a buffer into a FIFO
*
* Put a buffer to the end of a FIFO. If the buffer contains follow-up
* fragments this function will take care of inserting them as well
* into the FIFO.
*
* @param fifo Which FIFO to put the buffer to.
* @param buf Buffer.
*/
void net_buf_put(struct k_fifo *fifo, struct net_buf *buf);
/**
* @brief Decrements the reference count of a buffer.
*
* Decrements the reference count of a buffer and puts it back into the
* pool if the count reaches zero.
*
* @param buf A valid pointer on a buffer
*/
#if defined(CONFIG_NET_BUF_LOG)
void net_buf_unref_debug(struct net_buf *buf, const char *func, int line);
#define net_buf_unref(_buf) \
net_buf_unref_debug(_buf, __func__, __LINE__)
#else
void net_buf_unref(struct net_buf *buf);
#endif
/**
* @brief Increment the reference count of a buffer.
*
* @param buf A valid pointer on a buffer
*
* @return the buffer newly referenced
*/
struct net_buf *net_buf_ref(struct net_buf *buf);
/**
* @brief Duplicate buffer
*
* Duplicate given buffer including any data and headers currently stored.
*
* @param buf A valid pointer on a buffer
* @param timeout Affects the action taken should the pool be empty.
* If K_NO_WAIT, then return immediately. If K_FOREVER, then
* wait as long as necessary. Otherwise, wait up to the specified
* number of milliseconds before timing out.
*
* @return Duplicated buffer or NULL if out of buffers.
*/
struct net_buf *net_buf_clone(struct net_buf *buf, s32_t timeout);
/**
* @brief Get a pointer to the user data of a buffer.
*
* @param buf A valid pointer on a buffer
*
* @return Pointer to the user data of the buffer.
*/
static inline void *net_buf_user_data(const struct net_buf *buf)
{
return (void *)buf->user_data;
}
/** @def net_buf_reserve
* @brief Initialize buffer with the given headroom.
*
* Initializes a buffer with a given headroom. The buffer is not expected to
* contain any data when this API is called.
*
* @param buf Buffer to initialize.
* @param reserve How much headroom to reserve.
*/
#define net_buf_reserve(buf, reserve) net_buf_simple_reserve(&(buf)->b, \
reserve)
/**
* @def net_buf_add
* @brief Prepare data to be added at the end of the buffer
*
* Increments the data length of a buffer to account for more data
* at the end.
*
* @param buf Buffer to update.
* @param len Number of bytes to increment the length with.
*
* @return The original tail of the buffer.
*/
#define net_buf_add(buf, len) net_buf_simple_add(&(buf)->b, len)
/**
* @def net_buf_add_mem
* @brief Copy bytes from memory to the end of the buffer
*
* Copies the given number of bytes to the end of the buffer. Increments the
* data length of the buffer to account for more data at the end.
*
* @param buf Buffer to update.
* @param mem Location of data to be added.
* @param len Length of data to be added
*
* @return The original tail of the buffer.
*/
#define net_buf_add_mem(buf, mem, len) net_buf_simple_add_mem(&(buf)->b, \
mem, len)
/**
* @def net_buf_add_u8
* @brief Add (8-bit) byte at the end of the buffer
*
* Adds a byte at the end of the buffer. Increments the data length of
* the buffer to account for more data at the end.
*
* @param buf Buffer to update.
* @param val byte value to be added.
*
* @return Pointer to the value added
*/
#define net_buf_add_u8(buf, val) net_buf_simple_add_u8(&(buf)->b, val)
/**
* @def net_buf_add_le16
* @brief Add 16-bit value at the end of the buffer
*
* Adds 16-bit value in little endian format at the end of buffer.
* Increments the data length of a buffer to account for more data
* at the end.
*
* @param buf Buffer to update.
* @param val 16-bit value to be added.
*/
#define net_buf_add_le16(buf, val) net_buf_simple_add_le16(&(buf)->b, val)
/**
* @def net_buf_add_be16
* @brief Add 16-bit value at the end of the buffer
*
* Adds 16-bit value in big endian format at the end of buffer.
* Increments the data length of a buffer to account for more data
* at the end.
*
* @param buf Buffer to update.
* @param val 16-bit value to be added.
*/
#define net_buf_add_be16(buf, val) net_buf_simple_add_be16(&(buf)->b, val)
/**
* @def net_buf_add_le32
* @brief Add 32-bit value at the end of the buffer
*
* Adds 32-bit value in little endian format at the end of buffer.
* Increments the data length of a buffer to account for more data
* at the end.
*
* @param buf Buffer to update.
* @param val 32-bit value to be added.
*/
#define net_buf_add_le32(buf, val) net_buf_simple_add_le32(&(buf)->b, val)
/**
* @def net_buf_add_be32
* @brief Add 32-bit value at the end of the buffer
*
* Adds 32-bit value in big endian format at the end of buffer.
* Increments the data length of a buffer to account for more data
* at the end.
*
* @param buf Buffer to update.
* @param val 32-bit value to be added.
*/
#define net_buf_add_be32(buf, val) net_buf_simple_add_be32(&(buf)->b, val)
/**
* @def net_buf_push
* @brief Push data to the beginning of the buffer.
*
* Modifies the data pointer and buffer length to account for more data
* in the beginning of the buffer.
*
* @param buf Buffer to update.
* @param len Number of bytes to add to the beginning.
*
* @return The new beginning of the buffer data.
*/
#define net_buf_push(buf, len) net_buf_simple_push(&(buf)->b, len)
/**
* @def net_buf_push_le16
* @brief Push 16-bit value to the beginning of the buffer
*
* Adds 16-bit value in little endian format to the beginning of the
* buffer.
*
* @param buf Buffer to update.
* @param val 16-bit value to be pushed to the buffer.
*/
#define net_buf_push_le16(buf, val) net_buf_simple_push_le16(&(buf)->b, val)
/**
* @def net_buf_push_be16
* @brief Push 16-bit value to the beginning of the buffer
*
* Adds 16-bit value in little endian format to the beginning of the
* buffer.
*
* @param buf Buffer to update.
* @param val 16-bit value to be pushed to the buffer.
*/
#define net_buf_push_be16(buf, val) net_buf_simple_push_be16(&(buf)->b, val)
/**
* @def net_buf_push_u8
* @brief Push 8-bit value to the beginning of the buffer
*
* Adds 8-bit value the beginning of the buffer.
*
* @param buf Buffer to update.
* @param val 8-bit value to be pushed to the buffer.
*/
#define net_buf_push_u8(buf, val) net_buf_simple_push_u8(&(buf)->b, val)
/**
* @def net_buf_pull
* @brief Remove data from the beginning of the buffer.
*
* Removes data from the beginning of the buffer by modifying the data
* pointer and buffer length.
*
* @param buf Buffer to update.
* @param len Number of bytes to remove.
*
* @return New beginning of the buffer data.
*/
#define net_buf_pull(buf, len) net_buf_simple_pull(&(buf)->b, len)
/**
* @def net_buf_pull_mem
* @brief Remove data from the beginning of the buffer.
*
* Removes data from the beginning of the buffer by modifying the data
* pointer and buffer length.
*
* @param buf Buffer to update.
* @param len Number of bytes to remove.
*
* @return Pointer to the old beginning of the buffer data.
*/
#define net_buf_pull_mem(buf, len) net_buf_simple_pull_mem(&(buf)->b, len)
/**
* @def net_buf_pull_u8
* @brief Remove a 8-bit value from the beginning of the buffer
*
* Same idea as with net_buf_pull(), but a helper for operating on
* 8-bit values.
*
* @param buf A valid pointer on a buffer.
*
* @return The 8-bit removed value
*/
#define net_buf_pull_u8(buf) net_buf_simple_pull_u8(&(buf)->b)
/**
* @def net_buf_pull_le16
* @brief Remove and convert 16 bits from the beginning of the buffer.
*
* Same idea as with net_buf_pull(), but a helper for operating on
* 16-bit little endian data.
*
* @param buf A valid pointer on a buffer.
*
* @return 16-bit value converted from little endian to host endian.
*/
#define net_buf_pull_le16(buf) net_buf_simple_pull_le16(&(buf)->b)
/**
* @def net_buf_pull_be16
* @brief Remove and convert 16 bits from the beginning of the buffer.
*
* Same idea as with net_buf_pull(), but a helper for operating on
* 16-bit big endian data.
*
* @param buf A valid pointer on a buffer.
*
* @return 16-bit value converted from big endian to host endian.
*/
#define net_buf_pull_be16(buf) net_buf_simple_pull_be16(&(buf)->b)
/**
* @def net_buf_pull_le32
* @brief Remove and convert 32 bits from the beginning of the buffer.
*
* Same idea as with net_buf_pull(), but a helper for operating on
* 32-bit little endian data.
*
* @param buf A valid pointer on a buffer.
*
* @return 32-bit value converted from little endian to host endian.
*/
#define net_buf_pull_le32(buf) net_buf_simple_pull_le32(&(buf)->b)
/**
* @def net_buf_pull_be32
* @brief Remove and convert 32 bits from the beginning of the buffer.
*
* Same idea as with net_buf_pull(), but a helper for operating on
* 32-bit big endian data.
*
* @param buf A valid pointer on a buffer
*
* @return 32-bit value converted from big endian to host endian.
*/
#define net_buf_pull_be32(buf) net_buf_simple_pull_be32(&(buf)->b)
/**
* @def net_buf_tailroom
* @brief Check buffer tailroom.
*
* Check how much free space there is at the end of the buffer.
*
* @param buf A valid pointer on a buffer
*
* @return Number of bytes available at the end of the buffer.
*/
#define net_buf_tailroom(buf) net_buf_simple_tailroom(&(buf)->b)
/**
* @def net_buf_headroom
* @brief Check buffer headroom.
*
* Check how much free space there is in the beginning of the buffer.
*
* buf A valid pointer on a buffer
*
* @return Number of bytes available in the beginning of the buffer.
*/
#define net_buf_headroom(buf) net_buf_simple_headroom(&(buf)->b)
/**
* @def net_buf_tail
* @brief Get the tail pointer for a buffer.
*
* Get a pointer to the end of the data in a buffer.
*
* @param buf Buffer.
*
* @return Tail pointer for the buffer.
*/
#define net_buf_tail(buf) net_buf_simple_tail(&(buf)->b)
/** @brief Find the last fragment in the fragment list.
*
* @return Pointer to last fragment in the list.
*/
struct net_buf *net_buf_frag_last(struct net_buf *frags);
/** @brief Insert a new fragment to a chain of bufs.
*
* Insert a new fragment into the buffer fragments list after the parent.
*
* Note: This function takes ownership of the fragment reference so the
* caller is not required to unref.
*
* @param parent Parent buffer/fragment.
* @param frag Fragment to insert.
*/
void net_buf_frag_insert(struct net_buf *parent, struct net_buf *frag);
/** @brief Add a new fragment to the end of a chain of bufs.
*
* Append a new fragment into the buffer fragments list.
*
* Note: This function takes ownership of the fragment reference so the
* caller is not required to unref.
*
* @param head Head of the fragment chain.
* @param frag Fragment to add.
*
* @return New head of the fragment chain. Either head (if head
* was non-NULL) or frag (if head was NULL).
*/
struct net_buf *net_buf_frag_add(struct net_buf *head, struct net_buf *frag);
/** @brief Delete existing fragment from a chain of bufs.
*
* @param parent Parent buffer/fragment, or NULL if there is no parent.
* @param frag Fragment to delete.
*
* @return Pointer to the buffer following the fragment, or NULL if it
* had no further fragments.
*/
#if defined(CONFIG_NET_BUF_LOG)
struct net_buf *net_buf_frag_del_debug(struct net_buf *parent,
struct net_buf *frag,
const char *func, int line);
#define net_buf_frag_del(_parent, _frag) \
net_buf_frag_del_debug(_parent, _frag, __func__, __LINE__)
#else
struct net_buf *net_buf_frag_del(struct net_buf *parent, struct net_buf *frag);
#endif
/**
* @brief Copy bytes from net_buf chain starting at offset to linear buffer
*
* Copy (extract) @a len bytes from @a src net_buf chain, starting from @a
* offset in it, to a linear buffer @a dst. Return number of bytes actually
* copied, which may be less than requested, if net_buf chain doesn't have
* enough data, or destination buffer is too small.
*
* @param dst Destination buffer
* @param dst_len Destination buffer length
* @param src Source net_buf chain
* @param offset Starting offset to copy from
* @param len Number of bytes to copy
* @return number of bytes actually copied
*/
size_t net_buf_linearize(void *dst, size_t dst_len,
struct net_buf *src, size_t offset, size_t len);
/**
* @typedef net_buf_allocator_cb
* @brief Network buffer allocator callback.
*
* @details The allocator callback is called when net_buf_append_bytes
* needs to allocate a new net_buf.
*
* @param timeout Affects the action taken should the net buf pool be empty.
* If K_NO_WAIT, then return immediately. If K_FOREVER, then
* wait as long as necessary. Otherwise, wait up to the specified
* number of milliseconds before timing out.
* @param user_data The user data given in net_buf_append_bytes call.
* @return pointer to allocated net_buf or NULL on error.
*/
typedef struct net_buf *(*net_buf_allocator_cb)(s32_t timeout, void *user_data);
/**
* @brief Append data to a list of net_buf
*
* @details Append data to a net_buf. If there is not enough space in the
* net_buf then more net_buf will be added, unless there are no free net_buf
* and timeout occurs.
*
* @param buf Network buffer.
* @param len Total length of input data
* @param value Data to be added
* @param timeout Timeout is passed to the net_buf allocator callback.
* @param allocate_cb When a new net_buf is required, use this callback.
* @param user_data A user data pointer to be supplied to the allocate_cb.
* This pointer is can be anything from a mem_pool or a net_pkt, the
* logic is left up to the allocate_cb function.
*
* @return Length of data actually added. This may be less than input
* length if other timeout than K_FOREVER was used, and there
* were no free fragments in a pool to accommodate all data.
*/
size_t net_buf_append_bytes(struct net_buf *buf, size_t len,
const void *value, s32_t timeout,
net_buf_allocator_cb allocate_cb, void *user_data);
/**
* @brief Skip N number of bytes in a net_buf
*
* @details Skip N number of bytes starting from fragment's offset. If the total
* length of data is placed in multiple fragments, this function will skip from
* all fragments until it reaches N number of bytes. Any fully skipped buffers
* are removed from the net_buf list.
*
* @param buf Network buffer.
* @param len Total length of data to be skipped.
*
* @return Pointer to the fragment or
* NULL and pos is 0 after successful skip,
* NULL and pos is 0xffff otherwise.
*/
static inline struct net_buf *net_buf_skip(struct net_buf *buf, size_t len)
{
while (buf && len--) {
net_buf_pull_u8(buf);
if (!buf->len) {
buf = net_buf_frag_del(NULL, buf);
}
}
return buf;
}
/** @brief Calculate amount of bytes stored in fragments.
*
* Calculates the total amount of data stored in the given buffer and the
* fragments linked to it.
*
* @param buf Buffer to start off with.
*
* @return Number of bytes in the buffer and its fragments.
*/
static inline size_t net_buf_frags_len(struct net_buf *buf)
{
size_t bytes = 0;
while (buf) {
bytes += buf->len;
buf = buf->frags;
}
return bytes;
}
/**
* @}
*/
#ifdef __cplusplus
}
#endif
#endif /* ZEPHYR_INCLUDE_NET_BUF_H_ */
Reference in New Issue View Git Blame Copy Permalink