| /** |
| * @file |
| * pbuf API |
| */ |
| |
| /* |
| * Copyright (c) 2001-2004 Swedish Institute of Computer Science. |
| * All rights reserved. |
| * |
| * Redistribution and use in source and binary forms, with or without modification, |
| * are permitted provided that the following conditions are met: |
| * |
| * 1. Redistributions of source code must retain the above copyright notice, |
| * this list of conditions and the following disclaimer. |
| * 2. Redistributions in binary form must reproduce the above copyright notice, |
| * this list of conditions and the following disclaimer in the documentation |
| * and/or other materials provided with the distribution. |
| * 3. The name of the author may not be used to endorse or promote products |
| * derived from this software without specific prior written permission. |
| * |
| * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR IMPLIED |
| * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF |
| * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT |
| * SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, |
| * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT |
| * OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS |
| * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN |
| * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING |
| * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY |
| * OF SUCH DAMAGE. |
| * |
| * This file is part of the lwIP TCP/IP stack. |
| * |
| * Author: Adam Dunkels <adam@sics.se> |
| * |
| */ |
| |
| #ifndef LWIP_HDR_PBUF_H |
| #define LWIP_HDR_PBUF_H |
| |
| #include "lwip/opt.h" |
| #include "lwip/err.h" |
| |
| #ifdef __cplusplus |
| extern "C" { |
| #endif |
| |
| /** 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. */ |
| #ifndef LWIP_SUPPORT_CUSTOM_PBUF |
| #define LWIP_SUPPORT_CUSTOM_PBUF ((IP_FRAG && !LWIP_NETIF_TX_SINGLE_PBUF) || (LWIP_IPV6 && LWIP_IPV6_FRAG)) |
| #endif |
| |
| /** @ingroup pbuf |
| * PBUF_NEEDS_COPY(p): return a boolean value indicating whether the given |
| * pbuf needs to be copied in order to be kept around beyond the current call |
| * stack without risking being corrupted. The default setting provides safety: |
| * it will make a copy iof any pbuf chain that does not consist entirely of |
| * PBUF_ROM type pbufs. For setups with zero-copy support, it may be redefined |
| * to evaluate to true in all cases, for example. However, doing so also has an |
| * effect on the application side: any buffers that are *not* copied must also |
| * *not* be reused by the application after passing them to lwIP. For example, |
| * when setting PBUF_NEEDS_COPY to (0), after using udp_send() with a PBUF_RAM |
| * pbuf, the application must free the pbuf immediately, rather than reusing it |
| * for other purposes. For more background information on this, see tasks #6735 |
| * and #7896, and bugs #11400 and #49914. */ |
| #ifndef PBUF_NEEDS_COPY |
| #define PBUF_NEEDS_COPY(p) ((p)->type_internal & PBUF_TYPE_FLAG_DATA_VOLATILE) |
| #endif /* PBUF_NEEDS_COPY */ |
| |
| /* @todo: We need a mechanism to prevent wasting memory in every pbuf |
| (TCP vs. UDP, IPv4 vs. IPv6: UDP/IPv4 packets may waste up to 28 bytes) */ |
| |
| #define PBUF_TRANSPORT_HLEN 20 |
| #if LWIP_IPV6 |
| #define PBUF_IP_HLEN 40 |
| #else |
| #define PBUF_IP_HLEN 20 |
| #endif |
| |
| /** |
| * @ingroup pbuf |
| * Enumeration of pbuf layers |
| */ |
| typedef enum { |
| /** Includes spare room for transport layer header, e.g. UDP header. |
| * Use this if you intend to pass the pbuf to functions like udp_send(). |
| */ |
| PBUF_TRANSPORT = PBUF_LINK_ENCAPSULATION_HLEN + PBUF_LINK_HLEN + PBUF_IP_HLEN + PBUF_TRANSPORT_HLEN, |
| /** Includes spare room for IP header. |
| * Use this if you intend to pass the pbuf to functions like raw_send(). |
| */ |
| PBUF_IP = PBUF_LINK_ENCAPSULATION_HLEN + PBUF_LINK_HLEN + PBUF_IP_HLEN, |
| /** Includes spare room for link layer header (ethernet header). |
| * Use this if you intend to pass the pbuf to functions like ethernet_output(). |
| * @see PBUF_LINK_HLEN |
| */ |
| PBUF_LINK = PBUF_LINK_ENCAPSULATION_HLEN + PBUF_LINK_HLEN, |
| /** Includes spare room for additional encapsulation header before ethernet |
| * headers (e.g. 802.11). |
| * Use this if you intend to pass the pbuf to functions like netif->linkoutput(). |
| * @see PBUF_LINK_ENCAPSULATION_HLEN |
| */ |
| PBUF_RAW_TX = PBUF_LINK_ENCAPSULATION_HLEN, |
| /** Use this for input packets in a netif driver when calling netif->input() |
| * in the most common case - ethernet-layer netif driver. */ |
| PBUF_RAW = 0 |
| } pbuf_layer; |
| |
| |
| /* Base flags for pbuf_type definitions: */ |
| |
| /** Indicates that the payload directly follows the struct pbuf. |
| * This makes @ref pbuf_header work in both directions. */ |
| #define PBUF_TYPE_FLAG_STRUCT_DATA_CONTIGUOUS 0x80 |
| /** Indicates the data stored in this pbuf can change. If this pbuf needs |
| * to be queued, it must be copied/duplicated. */ |
| #define PBUF_TYPE_FLAG_DATA_VOLATILE 0x40 |
| /** 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*/ |
| #define PBUF_TYPE_ALLOC_SRC_MASK 0x0F |
| /** 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) */ |
| #define PBUF_ALLOC_FLAG_RX 0x0100 |
| /** Indicates the application needs the pbuf payload to be in one piece */ |
| #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 |
| /** First pbuf allocation type for applications */ |
| #define PBUF_TYPE_ALLOC_SRC_MASK_APP_MIN 0x03 |
| /** Last pbuf allocation type for applications */ |
| #define PBUF_TYPE_ALLOC_SRC_MASK_APP_MAX PBUF_TYPE_ALLOC_SRC_MASK |
| |
| /** |
| * @ingroup pbuf |
| * Enumeration of pbuf types |
| */ |
| typedef enum { |
| /** pbuf data is stored in RAM, used for TX mostly, struct pbuf and its payload |
| are allocated in one piece of contiguous memory (so the first payload byte |
| can be calculated from struct pbuf). |
| pbuf_alloc() allocates PBUF_RAM pbufs as unchained pbufs (although that might |
| change in future versions). |
| This should be used for all OUTGOING packets (TX).*/ |
| PBUF_RAM = (PBUF_ALLOC_FLAG_DATA_CONTIGUOUS | PBUF_TYPE_FLAG_STRUCT_DATA_CONTIGUOUS | PBUF_TYPE_ALLOC_SRC_MASK_STD_HEAP), |
| /** pbuf data is stored in ROM, i.e. struct pbuf and its payload are located in |
| totally different memory areas. Since it points to ROM, payload does not |
| have to be copied when queued for transmission. */ |
| PBUF_ROM = PBUF_TYPE_ALLOC_SRC_MASK_STD_MEMP_PBUF, |
| /** pbuf comes from the pbuf pool. Much like PBUF_ROM but payload might change |
| so it has to be duplicated when queued before transmitting, depending on |
| who has a 'ref' to it. */ |
| PBUF_REF = (PBUF_TYPE_FLAG_DATA_VOLATILE | PBUF_TYPE_ALLOC_SRC_MASK_STD_MEMP_PBUF), |
| /** pbuf payload refers to RAM. This one comes from a pool and should be used |
| for RX. Payload can be chained (scatter-gather RX) but like PBUF_RAM, struct |
| pbuf and its payload are allocated in one piece of contiguous memory (so |
| the first payload byte can be calculated from struct pbuf). |
| Don't use this for TX, if the pool becomes empty e.g. because of TCP queuing, |
| you are unable to receive TCP acks! */ |
| PBUF_POOL = (PBUF_ALLOC_FLAG_RX | PBUF_TYPE_FLAG_STRUCT_DATA_CONTIGUOUS | PBUF_TYPE_ALLOC_SRC_MASK_STD_MEMP_PBUF_POOL) |
| } pbuf_type; |
| |
| |
| /** indicates this packet's data should be immediately passed to the application */ |
| #define PBUF_FLAG_PUSH 0x01U |
| /** 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) */ |
| #define PBUF_FLAG_IS_CUSTOM 0x02U |
| /** indicates this pbuf is UDP multicast to be looped back */ |
| #define PBUF_FLAG_MCASTLOOP 0x04U |
| /** indicates this pbuf was received as link-level broadcast */ |
| #define PBUF_FLAG_LLBCAST 0x08U |
| /** indicates this pbuf was received as link-level multicast */ |
| #define PBUF_FLAG_LLMCAST 0x10U |
| /** indicates this pbuf includes a TCP FIN flag */ |
| #define PBUF_FLAG_TCP_FIN 0x20U |
| |
| /** Main packet buffer struct */ |
| struct pbuf { |
| /** next pbuf in singly linked pbuf chain */ |
| struct pbuf *next; |
| |
| /** pointer to the actual data in the buffer */ |
| void *payload; |
| |
| /** |
| * total length of this buffer and all next buffers in chain |
| * belonging to the same packet. |
| * |
| * For non-queue packet chains this is the invariant: |
| * p->tot_len == p->len + (p->next? p->next->tot_len: 0) |
| */ |
| u16_t tot_len; |
| |
| /** length of this buffer */ |
| u16_t len; |
| |
| /** a bit field indicating pbuf type and allocation sources |
| (see PBUF_TYPE_FLAG_*, PBUF_ALLOC_FLAG_* and PBUF_TYPE_ALLOC_SRC_MASK) |
| */ |
| u8_t type_internal; |
| |
| /** misc flags */ |
| u8_t flags; |
| |
| /** |
| * the reference count always equals the number of pointers |
| * that refer to this pbuf. This can be pointers from an application, |
| * the stack itself, or pbuf->next pointers from a chain. |
| */ |
| LWIP_PBUF_REF_T ref; |
| |
| /** For incoming packets, this contains the input netif's index */ |
| u8_t if_idx; |
| |
| /** In case the user needs to store data custom data on a pbuf */ |
| LWIP_PBUF_CUSTOM_DATA |
| }; |
| |
| |
| /** Helper struct for const-correctness only. |
| * The only meaning of this one is to provide a const payload pointer |
| * for PBUF_ROM type. |
| */ |
| struct pbuf_rom { |
| /** next pbuf in singly linked pbuf chain */ |
| struct pbuf *next; |
| |
| /** pointer to the actual data in the buffer */ |
| const void *payload; |
| }; |
| |
| #if LWIP_SUPPORT_CUSTOM_PBUF |
| /** Prototype for a function to free a custom pbuf */ |
| typedef void (*pbuf_free_custom_fn)(struct pbuf *p); |
| |
| /** A custom pbuf: like a pbuf, but following a function pointer to free it. */ |
| struct pbuf_custom { |
| /** The actual pbuf */ |
| struct pbuf pbuf; |
| /** This function is called when pbuf_free deallocates this pbuf(_custom) */ |
| pbuf_free_custom_fn custom_free_function; |
| }; |
| #endif /* LWIP_SUPPORT_CUSTOM_PBUF */ |
| |
| /** Define this to 0 to prevent freeing ooseq pbufs when the PBUF_POOL is empty */ |
| #ifndef PBUF_POOL_FREE_OOSEQ |
| #define PBUF_POOL_FREE_OOSEQ 1 |
| #endif /* PBUF_POOL_FREE_OOSEQ */ |
| #if LWIP_TCP && TCP_QUEUE_OOSEQ && NO_SYS && PBUF_POOL_FREE_OOSEQ |
| extern volatile u8_t pbuf_free_ooseq_pending; |
| void pbuf_free_ooseq(void); |
| /** When not using sys_check_timeouts(), call PBUF_CHECK_FREE_OOSEQ() |
| at regular intervals from main level to check if ooseq pbufs need to be |
| freed! */ |
| #define PBUF_CHECK_FREE_OOSEQ() do { if(pbuf_free_ooseq_pending) { \ |
| /* pbuf_alloc() reported PBUF_POOL to be empty -> try to free some \ |
| ooseq queued pbufs now */ \ |
| pbuf_free_ooseq(); }}while(0) |
| #else /* LWIP_TCP && TCP_QUEUE_OOSEQ && NO_SYS && PBUF_POOL_FREE_OOSEQ */ |
| /* Otherwise declare an empty PBUF_CHECK_FREE_OOSEQ */ |
| #define PBUF_CHECK_FREE_OOSEQ() |
| #endif /* LWIP_TCP && TCP_QUEUE_OOSEQ && NO_SYS && PBUF_POOL_FREE_OOSEQ*/ |
| |
| /* Initializes the pbuf module. This call is empty for now, but may not be in future. */ |
| #define pbuf_init() |
| |
| 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); |
| #if LWIP_SUPPORT_CUSTOM_PBUF |
| struct pbuf *pbuf_alloced_custom(pbuf_layer l, u16_t length, pbuf_type type, |
| struct pbuf_custom *p, void *payload_mem, |
| u16_t payload_mem_len); |
| #endif /* LWIP_SUPPORT_CUSTOM_PBUF */ |
| void pbuf_realloc(struct pbuf *p, u16_t size); |
| #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) |
| 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); |
| #if LWIP_CHECKSUM_ON_COPY |
| err_t pbuf_fill_chksum(struct pbuf *p, u16_t start_offset, const void *dataptr, |
| u16_t len, u16_t *chksum); |
| #endif /* LWIP_CHECKSUM_ON_COPY */ |
| #if LWIP_TCP && TCP_QUEUE_OOSEQ && LWIP_WND_SCALE |
| void pbuf_split_64k(struct pbuf *p, struct pbuf **rest); |
| #endif /* LWIP_TCP && TCP_QUEUE_OOSEQ && LWIP_WND_SCALE */ |
| |
| 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); |
| |
| #ifdef __cplusplus |
| } |
| #endif |
| |
| #endif /* LWIP_HDR_PBUF_H */ |