/** @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 #include #include #include #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_ */