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lwip/core/pbuf.c@0:d7bd7384a37c, 2016-12-07 (annotated)

Committer:
grzemich
Date:
Wed Dec 07 23:47:50 2016 +0000
Revision:
0:d7bd7384a37c
dgd

Who changed what in which revision?

UserRevisionLine numberNew contents of line
grzemich 0:d7bd7384a37c 1 /**
grzemich 0:d7bd7384a37c 2 * @file
grzemich 0:d7bd7384a37c 3 * Packet buffer management
grzemich 0:d7bd7384a37c 4 *
grzemich 0:d7bd7384a37c 5 * Packets are built from the pbuf data structure. It supports dynamic
grzemich 0:d7bd7384a37c 6 * memory allocation for packet contents or can reference externally
grzemich 0:d7bd7384a37c 7 * managed packet contents both in RAM and ROM. Quick allocation for
grzemich 0:d7bd7384a37c 8 * incoming packets is provided through pools with fixed sized pbufs.
grzemich 0:d7bd7384a37c 9 *
grzemich 0:d7bd7384a37c 10 * A packet may span over multiple pbufs, chained as a singly linked
grzemich 0:d7bd7384a37c 11 * list. This is called a "pbuf chain".
grzemich 0:d7bd7384a37c 12 *
grzemich 0:d7bd7384a37c 13 * Multiple packets may be queued, also using this singly linked list.
grzemich 0:d7bd7384a37c 14 * This is called a "packet queue".
grzemich 0:d7bd7384a37c 15 *
grzemich 0:d7bd7384a37c 16 * So, a packet queue consists of one or more pbuf chains, each of
grzemich 0:d7bd7384a37c 17 * which consist of one or more pbufs. CURRENTLY, PACKET QUEUES ARE
grzemich 0:d7bd7384a37c 18 * NOT SUPPORTED!!! Use helper structs to queue multiple packets.
grzemich 0:d7bd7384a37c 19 *
grzemich 0:d7bd7384a37c 20 * The differences between a pbuf chain and a packet queue are very
grzemich 0:d7bd7384a37c 21 * precise but subtle.
grzemich 0:d7bd7384a37c 22 *
grzemich 0:d7bd7384a37c 23 * The last pbuf of a packet has a ->tot_len field that equals the
grzemich 0:d7bd7384a37c 24 * ->len field. It can be found by traversing the list. If the last
grzemich 0:d7bd7384a37c 25 * pbuf of a packet has a ->next field other than NULL, more packets
grzemich 0:d7bd7384a37c 26 * are on the queue.
grzemich 0:d7bd7384a37c 27 *
grzemich 0:d7bd7384a37c 28 * Therefore, looping through a pbuf of a single packet, has an
grzemich 0:d7bd7384a37c 29 * loop end condition (tot_len == p->len), NOT (next == NULL).
grzemich 0:d7bd7384a37c 30 */
grzemich 0:d7bd7384a37c 31
grzemich 0:d7bd7384a37c 32 /*
grzemich 0:d7bd7384a37c 33 * Copyright (c) 2001-2004 Swedish Institute of Computer Science.
grzemich 0:d7bd7384a37c 34 * All rights reserved.
grzemich 0:d7bd7384a37c 35 *
grzemich 0:d7bd7384a37c 36 * Redistribution and use in source and binary forms, with or without modification,
grzemich 0:d7bd7384a37c 37 * are permitted provided that the following conditions are met:
grzemich 0:d7bd7384a37c 38 *
grzemich 0:d7bd7384a37c 39 * 1. Redistributions of source code must retain the above copyright notice,
grzemich 0:d7bd7384a37c 40 * this list of conditions and the following disclaimer.
grzemich 0:d7bd7384a37c 41 * 2. Redistributions in binary form must reproduce the above copyright notice,
grzemich 0:d7bd7384a37c 42 * this list of conditions and the following disclaimer in the documentation
grzemich 0:d7bd7384a37c 43 * and/or other materials provided with the distribution.
grzemich 0:d7bd7384a37c 44 * 3. The name of the author may not be used to endorse or promote products
grzemich 0:d7bd7384a37c 45 * derived from this software without specific prior written permission.
grzemich 0:d7bd7384a37c 46 *
grzemich 0:d7bd7384a37c 47 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR IMPLIED
grzemich 0:d7bd7384a37c 48 * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
grzemich 0:d7bd7384a37c 49 * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT
grzemich 0:d7bd7384a37c 50 * SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
grzemich 0:d7bd7384a37c 51 * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT
grzemich 0:d7bd7384a37c 52 * OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
grzemich 0:d7bd7384a37c 53 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
grzemich 0:d7bd7384a37c 54 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
grzemich 0:d7bd7384a37c 55 * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY
grzemich 0:d7bd7384a37c 56 * OF SUCH DAMAGE.
grzemich 0:d7bd7384a37c 57 *
grzemich 0:d7bd7384a37c 58 * This file is part of the lwIP TCP/IP stack.
grzemich 0:d7bd7384a37c 59 *
grzemich 0:d7bd7384a37c 60 * Author: Adam Dunkels <adam@sics.se>
grzemich 0:d7bd7384a37c 61 *
grzemich 0:d7bd7384a37c 62 */
grzemich 0:d7bd7384a37c 63
grzemich 0:d7bd7384a37c 64 #include "lwip/opt.h"
grzemich 0:d7bd7384a37c 65
grzemich 0:d7bd7384a37c 66 #include "lwip/stats.h"
grzemich 0:d7bd7384a37c 67 #include "lwip/def.h"
grzemich 0:d7bd7384a37c 68 #include "lwip/mem.h"
grzemich 0:d7bd7384a37c 69 #include "lwip/memp.h"
grzemich 0:d7bd7384a37c 70 #include "lwip/pbuf.h"
grzemich 0:d7bd7384a37c 71 #include "lwip/sys.h"
grzemich 0:d7bd7384a37c 72 #include "arch/perf.h"
grzemich 0:d7bd7384a37c 73 #if TCP_QUEUE_OOSEQ
grzemich 0:d7bd7384a37c 74 #include "lwip/tcp_impl.h"
grzemich 0:d7bd7384a37c 75 #endif
grzemich 0:d7bd7384a37c 76 #if LWIP_CHECKSUM_ON_COPY
grzemich 0:d7bd7384a37c 77 #include "lwip/inet_chksum.h"
grzemich 0:d7bd7384a37c 78 #endif
grzemich 0:d7bd7384a37c 79
grzemich 0:d7bd7384a37c 80 #include <string.h>
grzemich 0:d7bd7384a37c 81
grzemich 0:d7bd7384a37c 82 #define SIZEOF_STRUCT_PBUF LWIP_MEM_ALIGN_SIZE(sizeof(struct pbuf))
grzemich 0:d7bd7384a37c 83 /* Since the pool is created in memp, PBUF_POOL_BUFSIZE will be automatically
grzemich 0:d7bd7384a37c 84 aligned there. Therefore, PBUF_POOL_BUFSIZE_ALIGNED can be used here. */
grzemich 0:d7bd7384a37c 85 #define PBUF_POOL_BUFSIZE_ALIGNED LWIP_MEM_ALIGN_SIZE(PBUF_POOL_BUFSIZE)
grzemich 0:d7bd7384a37c 86
grzemich 0:d7bd7384a37c 87 #if !LWIP_TCP || !TCP_QUEUE_OOSEQ || NO_SYS
grzemich 0:d7bd7384a37c 88 #define PBUF_POOL_IS_EMPTY()
grzemich 0:d7bd7384a37c 89 #else /* !LWIP_TCP || !TCP_QUEUE_OOSEQ || NO_SYS */
grzemich 0:d7bd7384a37c 90 /** Define this to 0 to prevent freeing ooseq pbufs when the PBUF_POOL is empty */
grzemich 0:d7bd7384a37c 91 #ifndef PBUF_POOL_FREE_OOSEQ
grzemich 0:d7bd7384a37c 92 #define PBUF_POOL_FREE_OOSEQ 1
grzemich 0:d7bd7384a37c 93 #endif /* PBUF_POOL_FREE_OOSEQ */
grzemich 0:d7bd7384a37c 94
grzemich 0:d7bd7384a37c 95 #if PBUF_POOL_FREE_OOSEQ
grzemich 0:d7bd7384a37c 96 #include "lwip/tcpip.h"
grzemich 0:d7bd7384a37c 97 #define PBUF_POOL_IS_EMPTY() pbuf_pool_is_empty()
grzemich 0:d7bd7384a37c 98 static u8_t pbuf_free_ooseq_queued;
grzemich 0:d7bd7384a37c 99 /**
grzemich 0:d7bd7384a37c 100 * Attempt to reclaim some memory from queued out-of-sequence TCP segments
grzemich 0:d7bd7384a37c 101 * if we run out of pool pbufs. It's better to give priority to new packets
grzemich 0:d7bd7384a37c 102 * if we're running out.
grzemich 0:d7bd7384a37c 103 *
grzemich 0:d7bd7384a37c 104 * This must be done in the correct thread context therefore this function
grzemich 0:d7bd7384a37c 105 * can only be used with NO_SYS=0 and through tcpip_callback.
grzemich 0:d7bd7384a37c 106 */
grzemich 0:d7bd7384a37c 107 static void
grzemich 0:d7bd7384a37c 108 pbuf_free_ooseq(void* arg)
grzemich 0:d7bd7384a37c 109 {
grzemich 0:d7bd7384a37c 110 struct tcp_pcb* pcb;
grzemich 0:d7bd7384a37c 111 SYS_ARCH_DECL_PROTECT(old_level);
grzemich 0:d7bd7384a37c 112 LWIP_UNUSED_ARG(arg);
grzemich 0:d7bd7384a37c 113
grzemich 0:d7bd7384a37c 114 SYS_ARCH_PROTECT(old_level);
grzemich 0:d7bd7384a37c 115 pbuf_free_ooseq_queued = 0;
grzemich 0:d7bd7384a37c 116 SYS_ARCH_UNPROTECT(old_level);
grzemich 0:d7bd7384a37c 117
grzemich 0:d7bd7384a37c 118 for (pcb = tcp_active_pcbs; NULL != pcb; pcb = pcb->next) {
grzemich 0:d7bd7384a37c 119 if (NULL != pcb->ooseq) {
grzemich 0:d7bd7384a37c 120 /** Free the ooseq pbufs of one PCB only */
grzemich 0:d7bd7384a37c 121 LWIP_DEBUGF(PBUF_DEBUG | LWIP_DBG_TRACE, ("pbuf_free_ooseq: freeing out-of-sequence pbufs\n"));
grzemich 0:d7bd7384a37c 122 tcp_segs_free(pcb->ooseq);
grzemich 0:d7bd7384a37c 123 pcb->ooseq = NULL;
grzemich 0:d7bd7384a37c 124 return;
grzemich 0:d7bd7384a37c 125 }
grzemich 0:d7bd7384a37c 126 }
grzemich 0:d7bd7384a37c 127 }
grzemich 0:d7bd7384a37c 128
grzemich 0:d7bd7384a37c 129 /** Queue a call to pbuf_free_ooseq if not already queued. */
grzemich 0:d7bd7384a37c 130 static void
grzemich 0:d7bd7384a37c 131 pbuf_pool_is_empty(void)
grzemich 0:d7bd7384a37c 132 {
grzemich 0:d7bd7384a37c 133 u8_t queued;
grzemich 0:d7bd7384a37c 134 SYS_ARCH_DECL_PROTECT(old_level);
grzemich 0:d7bd7384a37c 135
grzemich 0:d7bd7384a37c 136 SYS_ARCH_PROTECT(old_level);
grzemich 0:d7bd7384a37c 137 queued = pbuf_free_ooseq_queued;
grzemich 0:d7bd7384a37c 138 pbuf_free_ooseq_queued = 1;
grzemich 0:d7bd7384a37c 139 SYS_ARCH_UNPROTECT(old_level);
grzemich 0:d7bd7384a37c 140
grzemich 0:d7bd7384a37c 141 if(!queued) {
grzemich 0:d7bd7384a37c 142 /* queue a call to pbuf_free_ooseq if not already queued */
grzemich 0:d7bd7384a37c 143 if(tcpip_callback_with_block(pbuf_free_ooseq, NULL, 0) != ERR_OK) {
grzemich 0:d7bd7384a37c 144 SYS_ARCH_PROTECT(old_level);
grzemich 0:d7bd7384a37c 145 pbuf_free_ooseq_queued = 0;
grzemich 0:d7bd7384a37c 146 SYS_ARCH_UNPROTECT(old_level);
grzemich 0:d7bd7384a37c 147 }
grzemich 0:d7bd7384a37c 148 }
grzemich 0:d7bd7384a37c 149 }
grzemich 0:d7bd7384a37c 150 #endif /* PBUF_POOL_FREE_OOSEQ */
grzemich 0:d7bd7384a37c 151 #endif /* !LWIP_TCP || !TCP_QUEUE_OOSEQ || NO_SYS */
grzemich 0:d7bd7384a37c 152
grzemich 0:d7bd7384a37c 153 /**
grzemich 0:d7bd7384a37c 154 * Allocates a pbuf of the given type (possibly a chain for PBUF_POOL type).
grzemich 0:d7bd7384a37c 155 *
grzemich 0:d7bd7384a37c 156 * The actual memory allocated for the pbuf is determined by the
grzemich 0:d7bd7384a37c 157 * layer at which the pbuf is allocated and the requested size
grzemich 0:d7bd7384a37c 158 * (from the size parameter).
grzemich 0:d7bd7384a37c 159 *
grzemich 0:d7bd7384a37c 160 * @param layer flag to define header size
grzemich 0:d7bd7384a37c 161 * @param length size of the pbuf's payload
grzemich 0:d7bd7384a37c 162 * @param type this parameter decides how and where the pbuf
grzemich 0:d7bd7384a37c 163 * should be allocated as follows:
grzemich 0:d7bd7384a37c 164 *
grzemich 0:d7bd7384a37c 165 * - PBUF_RAM: buffer memory for pbuf is allocated as one large
grzemich 0:d7bd7384a37c 166 * chunk. This includes protocol headers as well.
grzemich 0:d7bd7384a37c 167 * - PBUF_ROM: no buffer memory is allocated for the pbuf, even for
grzemich 0:d7bd7384a37c 168 * protocol headers. Additional headers must be prepended
grzemich 0:d7bd7384a37c 169 * by allocating another pbuf and chain in to the front of
grzemich 0:d7bd7384a37c 170 * the ROM pbuf. It is assumed that the memory used is really
grzemich 0:d7bd7384a37c 171 * similar to ROM in that it is immutable and will not be
grzemich 0:d7bd7384a37c 172 * changed. Memory which is dynamic should generally not
grzemich 0:d7bd7384a37c 173 * be attached to PBUF_ROM pbufs. Use PBUF_REF instead.
grzemich 0:d7bd7384a37c 174 * - PBUF_REF: no buffer memory is allocated for the pbuf, even for
grzemich 0:d7bd7384a37c 175 * protocol headers. It is assumed that the pbuf is only
grzemich 0:d7bd7384a37c 176 * being used in a single thread. If the pbuf gets queued,
grzemich 0:d7bd7384a37c 177 * then pbuf_take should be called to copy the buffer.
grzemich 0:d7bd7384a37c 178 * - PBUF_POOL: the pbuf is allocated as a pbuf chain, with pbufs from
grzemich 0:d7bd7384a37c 179 * the pbuf pool that is allocated during pbuf_init().
grzemich 0:d7bd7384a37c 180 *
grzemich 0:d7bd7384a37c 181 * @return the allocated pbuf. If multiple pbufs where allocated, this
grzemich 0:d7bd7384a37c 182 * is the first pbuf of a pbuf chain.
grzemich 0:d7bd7384a37c 183 */
grzemich 0:d7bd7384a37c 184 struct pbuf *
grzemich 0:d7bd7384a37c 185 pbuf_alloc(pbuf_layer layer, u16_t length, pbuf_type type)
grzemich 0:d7bd7384a37c 186 {
grzemich 0:d7bd7384a37c 187 struct pbuf *p, *q, *r;
grzemich 0:d7bd7384a37c 188 u16_t offset;
grzemich 0:d7bd7384a37c 189 s32_t rem_len; /* remaining length */
grzemich 0:d7bd7384a37c 190 LWIP_DEBUGF(PBUF_DEBUG | LWIP_DBG_TRACE, ("pbuf_alloc(length=%"U16_F")\n", length));
grzemich 0:d7bd7384a37c 191
grzemich 0:d7bd7384a37c 192 /* determine header offset */
grzemich 0:d7bd7384a37c 193 offset = 0;
grzemich 0:d7bd7384a37c 194 switch (layer) {
grzemich 0:d7bd7384a37c 195 case PBUF_TRANSPORT:
grzemich 0:d7bd7384a37c 196 /* add room for transport (often TCP) layer header */
grzemich 0:d7bd7384a37c 197 offset += PBUF_TRANSPORT_HLEN;
grzemich 0:d7bd7384a37c 198 /* FALLTHROUGH */
grzemich 0:d7bd7384a37c 199 case PBUF_IP:
grzemich 0:d7bd7384a37c 200 /* add room for IP layer header */
grzemich 0:d7bd7384a37c 201 offset += PBUF_IP_HLEN;
grzemich 0:d7bd7384a37c 202 /* FALLTHROUGH */
grzemich 0:d7bd7384a37c 203 case PBUF_LINK:
grzemich 0:d7bd7384a37c 204 /* add room for link layer header */
grzemich 0:d7bd7384a37c 205 offset += PBUF_LINK_HLEN;
grzemich 0:d7bd7384a37c 206 break;
grzemich 0:d7bd7384a37c 207 case PBUF_RAW:
grzemich 0:d7bd7384a37c 208 break;
grzemich 0:d7bd7384a37c 209 default:
grzemich 0:d7bd7384a37c 210 LWIP_ASSERT("pbuf_alloc: bad pbuf layer", 0);
grzemich 0:d7bd7384a37c 211 return NULL;
grzemich 0:d7bd7384a37c 212 }
grzemich 0:d7bd7384a37c 213
grzemich 0:d7bd7384a37c 214 switch (type) {
grzemich 0:d7bd7384a37c 215 case PBUF_POOL:
grzemich 0:d7bd7384a37c 216 /* allocate head of pbuf chain into p */
grzemich 0:d7bd7384a37c 217 p = (struct pbuf *)memp_malloc(MEMP_PBUF_POOL);
grzemich 0:d7bd7384a37c 218 LWIP_DEBUGF(PBUF_DEBUG | LWIP_DBG_TRACE, ("pbuf_alloc: allocated pbuf %p\n", (void *)p));
grzemich 0:d7bd7384a37c 219 if (p == NULL) {
grzemich 0:d7bd7384a37c 220 PBUF_POOL_IS_EMPTY();
grzemich 0:d7bd7384a37c 221 return NULL;
grzemich 0:d7bd7384a37c 222 }
grzemich 0:d7bd7384a37c 223 p->type = type;
grzemich 0:d7bd7384a37c 224 p->next = NULL;
grzemich 0:d7bd7384a37c 225
grzemich 0:d7bd7384a37c 226 /* make the payload pointer point 'offset' bytes into pbuf data memory */
grzemich 0:d7bd7384a37c 227 p->payload = LWIP_MEM_ALIGN((void *)((u8_t *)p + (SIZEOF_STRUCT_PBUF + offset)));
grzemich 0:d7bd7384a37c 228 LWIP_ASSERT("pbuf_alloc: pbuf p->payload properly aligned",
grzemich 0:d7bd7384a37c 229 ((mem_ptr_t)p->payload % MEM_ALIGNMENT) == 0);
grzemich 0:d7bd7384a37c 230 /* the total length of the pbuf chain is the requested size */
grzemich 0:d7bd7384a37c 231 p->tot_len = length;
grzemich 0:d7bd7384a37c 232 /* set the length of the first pbuf in the chain */
grzemich 0:d7bd7384a37c 233 p->len = LWIP_MIN(length, PBUF_POOL_BUFSIZE_ALIGNED - LWIP_MEM_ALIGN_SIZE(offset));
grzemich 0:d7bd7384a37c 234 LWIP_ASSERT("check p->payload + p->len does not overflow pbuf",
grzemich 0:d7bd7384a37c 235 ((u8_t*)p->payload + p->len <=
grzemich 0:d7bd7384a37c 236 (u8_t*)p + SIZEOF_STRUCT_PBUF + PBUF_POOL_BUFSIZE_ALIGNED));
grzemich 0:d7bd7384a37c 237 LWIP_ASSERT("PBUF_POOL_BUFSIZE must be bigger than MEM_ALIGNMENT",
grzemich 0:d7bd7384a37c 238 (PBUF_POOL_BUFSIZE_ALIGNED - LWIP_MEM_ALIGN_SIZE(offset)) > 0 );
grzemich 0:d7bd7384a37c 239 /* set reference count (needed here in case we fail) */
grzemich 0:d7bd7384a37c 240 p->ref = 1;
grzemich 0:d7bd7384a37c 241
grzemich 0:d7bd7384a37c 242 /* now allocate the tail of the pbuf chain */
grzemich 0:d7bd7384a37c 243
grzemich 0:d7bd7384a37c 244 /* remember first pbuf for linkage in next iteration */
grzemich 0:d7bd7384a37c 245 r = p;
grzemich 0:d7bd7384a37c 246 /* remaining length to be allocated */
grzemich 0:d7bd7384a37c 247 rem_len = length - p->len;
grzemich 0:d7bd7384a37c 248 /* any remaining pbufs to be allocated? */
grzemich 0:d7bd7384a37c 249 while (rem_len > 0) {
grzemich 0:d7bd7384a37c 250 q = (struct pbuf *)memp_malloc(MEMP_PBUF_POOL);
grzemich 0:d7bd7384a37c 251 if (q == NULL) {
grzemich 0:d7bd7384a37c 252 PBUF_POOL_IS_EMPTY();
grzemich 0:d7bd7384a37c 253 /* free chain so far allocated */
grzemich 0:d7bd7384a37c 254 pbuf_free(p);
grzemich 0:d7bd7384a37c 255 /* bail out unsuccesfully */
grzemich 0:d7bd7384a37c 256 return NULL;
grzemich 0:d7bd7384a37c 257 }
grzemich 0:d7bd7384a37c 258 q->type = type;
grzemich 0:d7bd7384a37c 259 q->flags = 0;
grzemich 0:d7bd7384a37c 260 q->next = NULL;
grzemich 0:d7bd7384a37c 261 /* make previous pbuf point to this pbuf */
grzemich 0:d7bd7384a37c 262 r->next = q;
grzemich 0:d7bd7384a37c 263 /* set total length of this pbuf and next in chain */
grzemich 0:d7bd7384a37c 264 LWIP_ASSERT("rem_len < max_u16_t", rem_len < 0xffff);
grzemich 0:d7bd7384a37c 265 q->tot_len = (u16_t)rem_len;
grzemich 0:d7bd7384a37c 266 /* this pbuf length is pool size, unless smaller sized tail */
grzemich 0:d7bd7384a37c 267 q->len = LWIP_MIN((u16_t)rem_len, PBUF_POOL_BUFSIZE_ALIGNED);
grzemich 0:d7bd7384a37c 268 q->payload = (void *)((u8_t *)q + SIZEOF_STRUCT_PBUF);
grzemich 0:d7bd7384a37c 269 LWIP_ASSERT("pbuf_alloc: pbuf q->payload properly aligned",
grzemich 0:d7bd7384a37c 270 ((mem_ptr_t)q->payload % MEM_ALIGNMENT) == 0);
grzemich 0:d7bd7384a37c 271 LWIP_ASSERT("check p->payload + p->len does not overflow pbuf",
grzemich 0:d7bd7384a37c 272 ((u8_t*)p->payload + p->len <=
grzemich 0:d7bd7384a37c 273 (u8_t*)p + SIZEOF_STRUCT_PBUF + PBUF_POOL_BUFSIZE_ALIGNED));
grzemich 0:d7bd7384a37c 274 q->ref = 1;
grzemich 0:d7bd7384a37c 275 /* calculate remaining length to be allocated */
grzemich 0:d7bd7384a37c 276 rem_len -= q->len;
grzemich 0:d7bd7384a37c 277 /* remember this pbuf for linkage in next iteration */
grzemich 0:d7bd7384a37c 278 r = q;
grzemich 0:d7bd7384a37c 279 }
grzemich 0:d7bd7384a37c 280 /* end of chain */
grzemich 0:d7bd7384a37c 281 /*r->next = NULL;*/
grzemich 0:d7bd7384a37c 282
grzemich 0:d7bd7384a37c 283 break;
grzemich 0:d7bd7384a37c 284 case PBUF_RAM:
grzemich 0:d7bd7384a37c 285 /* If pbuf is to be allocated in RAM, allocate memory for it. */
grzemich 0:d7bd7384a37c 286 p = (struct pbuf*)mem_malloc(LWIP_MEM_ALIGN_SIZE(SIZEOF_STRUCT_PBUF + offset) + LWIP_MEM_ALIGN_SIZE(length));
grzemich 0:d7bd7384a37c 287 if (p == NULL) {
grzemich 0:d7bd7384a37c 288 return NULL;
grzemich 0:d7bd7384a37c 289 }
grzemich 0:d7bd7384a37c 290 /* Set up internal structure of the pbuf. */
grzemich 0:d7bd7384a37c 291 p->payload = LWIP_MEM_ALIGN((void *)((u8_t *)p + SIZEOF_STRUCT_PBUF + offset));
grzemich 0:d7bd7384a37c 292 p->len = p->tot_len = length;
grzemich 0:d7bd7384a37c 293 p->next = NULL;
grzemich 0:d7bd7384a37c 294 p->type = type;
grzemich 0:d7bd7384a37c 295
grzemich 0:d7bd7384a37c 296 LWIP_ASSERT("pbuf_alloc: pbuf->payload properly aligned",
grzemich 0:d7bd7384a37c 297 ((mem_ptr_t)p->payload % MEM_ALIGNMENT) == 0);
grzemich 0:d7bd7384a37c 298 break;
grzemich 0:d7bd7384a37c 299 /* pbuf references existing (non-volatile static constant) ROM payload? */
grzemich 0:d7bd7384a37c 300 case PBUF_ROM:
grzemich 0:d7bd7384a37c 301 /* pbuf references existing (externally allocated) RAM payload? */
grzemich 0:d7bd7384a37c 302 case PBUF_REF:
grzemich 0:d7bd7384a37c 303 /* only allocate memory for the pbuf structure */
grzemich 0:d7bd7384a37c 304 p = (struct pbuf *)memp_malloc(MEMP_PBUF);
grzemich 0:d7bd7384a37c 305 if (p == NULL) {
grzemich 0:d7bd7384a37c 306 LWIP_DEBUGF(PBUF_DEBUG | LWIP_DBG_LEVEL_SERIOUS,
grzemich 0:d7bd7384a37c 307 ("pbuf_alloc: Could not allocate MEMP_PBUF for PBUF_%s.\n",
grzemich 0:d7bd7384a37c 308 (type == PBUF_ROM) ? "ROM" : "REF"));
grzemich 0:d7bd7384a37c 309 return NULL;
grzemich 0:d7bd7384a37c 310 }
grzemich 0:d7bd7384a37c 311 /* caller must set this field properly, afterwards */
grzemich 0:d7bd7384a37c 312 p->payload = NULL;
grzemich 0:d7bd7384a37c 313 p->len = p->tot_len = length;
grzemich 0:d7bd7384a37c 314 p->next = NULL;
grzemich 0:d7bd7384a37c 315 p->type = type;
grzemich 0:d7bd7384a37c 316 break;
grzemich 0:d7bd7384a37c 317 default:
grzemich 0:d7bd7384a37c 318 LWIP_ASSERT("pbuf_alloc: erroneous type", 0);
grzemich 0:d7bd7384a37c 319 return NULL;
grzemich 0:d7bd7384a37c 320 }
grzemich 0:d7bd7384a37c 321 /* set reference count */
grzemich 0:d7bd7384a37c 322 p->ref = 1;
grzemich 0:d7bd7384a37c 323 /* set flags */
grzemich 0:d7bd7384a37c 324 p->flags = 0;
grzemich 0:d7bd7384a37c 325 LWIP_DEBUGF(PBUF_DEBUG | LWIP_DBG_TRACE, ("pbuf_alloc(length=%"U16_F") == %p\n", length, (void *)p));
grzemich 0:d7bd7384a37c 326 return p;
grzemich 0:d7bd7384a37c 327 }
grzemich 0:d7bd7384a37c 328
grzemich 0:d7bd7384a37c 329 #if LWIP_SUPPORT_CUSTOM_PBUF
grzemich 0:d7bd7384a37c 330 /** Initialize a custom pbuf (already allocated).
grzemich 0:d7bd7384a37c 331 *
grzemich 0:d7bd7384a37c 332 * @param layer flag to define header size
grzemich 0:d7bd7384a37c 333 * @param length size of the pbuf's payload
grzemich 0:d7bd7384a37c 334 * @param type type of the pbuf (only used to treat the pbuf accordingly, as
grzemich 0:d7bd7384a37c 335 * this function allocates no memory)
grzemich 0:d7bd7384a37c 336 * @param p pointer to the custom pbuf to initialize (already allocated)
grzemich 0:d7bd7384a37c 337 * @param payload_mem pointer to the buffer that is used for payload and headers,
grzemich 0:d7bd7384a37c 338 * must be at least big enough to hold 'length' plus the header size,
grzemich 0:d7bd7384a37c 339 * may be NULL if set later
grzemich 0:d7bd7384a37c 340 * @param payload_mem_len the size of the 'payload_mem' buffer, must be at least
grzemich 0:d7bd7384a37c 341 * big enough to hold 'length' plus the header size
grzemich 0:d7bd7384a37c 342 */
grzemich 0:d7bd7384a37c 343 struct pbuf*
grzemich 0:d7bd7384a37c 344 pbuf_alloced_custom(pbuf_layer l, u16_t length, pbuf_type type, struct pbuf_custom *p,
grzemich 0:d7bd7384a37c 345 void *payload_mem, u16_t payload_mem_len)
grzemich 0:d7bd7384a37c 346 {
grzemich 0:d7bd7384a37c 347 u16_t offset;
grzemich 0:d7bd7384a37c 348 LWIP_DEBUGF(PBUF_DEBUG | LWIP_DBG_TRACE, ("pbuf_alloced_custom(length=%"U16_F")\n", length));
grzemich 0:d7bd7384a37c 349
grzemich 0:d7bd7384a37c 350 /* determine header offset */
grzemich 0:d7bd7384a37c 351 offset = 0;
grzemich 0:d7bd7384a37c 352 switch (l) {
grzemich 0:d7bd7384a37c 353 case PBUF_TRANSPORT:
grzemich 0:d7bd7384a37c 354 /* add room for transport (often TCP) layer header */
grzemich 0:d7bd7384a37c 355 offset += PBUF_TRANSPORT_HLEN;
grzemich 0:d7bd7384a37c 356 /* FALLTHROUGH */
grzemich 0:d7bd7384a37c 357 case PBUF_IP:
grzemich 0:d7bd7384a37c 358 /* add room for IP layer header */
grzemich 0:d7bd7384a37c 359 offset += PBUF_IP_HLEN;
grzemich 0:d7bd7384a37c 360 /* FALLTHROUGH */
grzemich 0:d7bd7384a37c 361 case PBUF_LINK:
grzemich 0:d7bd7384a37c 362 /* add room for link layer header */
grzemich 0:d7bd7384a37c 363 offset += PBUF_LINK_HLEN;
grzemich 0:d7bd7384a37c 364 break;
grzemich 0:d7bd7384a37c 365 case PBUF_RAW:
grzemich 0:d7bd7384a37c 366 break;
grzemich 0:d7bd7384a37c 367 default:
grzemich 0:d7bd7384a37c 368 LWIP_ASSERT("pbuf_alloced_custom: bad pbuf layer", 0);
grzemich 0:d7bd7384a37c 369 return NULL;
grzemich 0:d7bd7384a37c 370 }
grzemich 0:d7bd7384a37c 371
grzemich 0:d7bd7384a37c 372 if (LWIP_MEM_ALIGN_SIZE(offset) + length < payload_mem_len) {
grzemich 0:d7bd7384a37c 373 LWIP_DEBUGF(PBUF_DEBUG | LWIP_DBG_LEVEL_WARNING, ("pbuf_alloced_custom(length=%"U16_F") buffer too short\n", length));
grzemich 0:d7bd7384a37c 374 return NULL;
grzemich 0:d7bd7384a37c 375 }
grzemich 0:d7bd7384a37c 376
grzemich 0:d7bd7384a37c 377 p->pbuf.next = NULL;
grzemich 0:d7bd7384a37c 378 if (payload_mem != NULL) {
grzemich 0:d7bd7384a37c 379 p->pbuf.payload = (void *)((u8_t *)payload_mem + offset);
grzemich 0:d7bd7384a37c 380 } else {
grzemich 0:d7bd7384a37c 381 p->pbuf.payload = NULL;
grzemich 0:d7bd7384a37c 382 }
grzemich 0:d7bd7384a37c 383 p->pbuf.flags = PBUF_FLAG_IS_CUSTOM;
grzemich 0:d7bd7384a37c 384 p->pbuf.len = p->pbuf.tot_len = length;
grzemich 0:d7bd7384a37c 385 p->pbuf.type = type;
grzemich 0:d7bd7384a37c 386 p->pbuf.ref = 1;
grzemich 0:d7bd7384a37c 387 return &p->pbuf;
grzemich 0:d7bd7384a37c 388 }
grzemich 0:d7bd7384a37c 389 #endif /* LWIP_SUPPORT_CUSTOM_PBUF */
grzemich 0:d7bd7384a37c 390
grzemich 0:d7bd7384a37c 391 /**
grzemich 0:d7bd7384a37c 392 * Shrink a pbuf chain to a desired length.
grzemich 0:d7bd7384a37c 393 *
grzemich 0:d7bd7384a37c 394 * @param p pbuf to shrink.
grzemich 0:d7bd7384a37c 395 * @param new_len desired new length of pbuf chain
grzemich 0:d7bd7384a37c 396 *
grzemich 0:d7bd7384a37c 397 * Depending on the desired length, the first few pbufs in a chain might
grzemich 0:d7bd7384a37c 398 * be skipped and left unchanged. The new last pbuf in the chain will be
grzemich 0:d7bd7384a37c 399 * resized, and any remaining pbufs will be freed.
grzemich 0:d7bd7384a37c 400 *
grzemich 0:d7bd7384a37c 401 * @note If the pbuf is ROM/REF, only the ->tot_len and ->len fields are adjusted.
grzemich 0:d7bd7384a37c 402 * @note May not be called on a packet queue.
grzemich 0:d7bd7384a37c 403 *
grzemich 0:d7bd7384a37c 404 * @note Despite its name, pbuf_realloc cannot grow the size of a pbuf (chain).
grzemich 0:d7bd7384a37c 405 */
grzemich 0:d7bd7384a37c 406 void
grzemich 0:d7bd7384a37c 407 pbuf_realloc(struct pbuf *p, u16_t new_len)
grzemich 0:d7bd7384a37c 408 {
grzemich 0:d7bd7384a37c 409 struct pbuf *q;
grzemich 0:d7bd7384a37c 410 u16_t rem_len; /* remaining length */
grzemich 0:d7bd7384a37c 411 s32_t grow;
grzemich 0:d7bd7384a37c 412
grzemich 0:d7bd7384a37c 413 LWIP_ASSERT("pbuf_realloc: p != NULL", p != NULL);
grzemich 0:d7bd7384a37c 414 LWIP_ASSERT("pbuf_realloc: sane p->type", p->type == PBUF_POOL ||
grzemich 0:d7bd7384a37c 415 p->type == PBUF_ROM ||
grzemich 0:d7bd7384a37c 416 p->type == PBUF_RAM ||
grzemich 0:d7bd7384a37c 417 p->type == PBUF_REF);
grzemich 0:d7bd7384a37c 418
grzemich 0:d7bd7384a37c 419 /* desired length larger than current length? */
grzemich 0:d7bd7384a37c 420 if (new_len >= p->tot_len) {
grzemich 0:d7bd7384a37c 421 /* enlarging not yet supported */
grzemich 0:d7bd7384a37c 422 return;
grzemich 0:d7bd7384a37c 423 }
grzemich 0:d7bd7384a37c 424
grzemich 0:d7bd7384a37c 425 /* the pbuf chain grows by (new_len - p->tot_len) bytes
grzemich 0:d7bd7384a37c 426 * (which may be negative in case of shrinking) */
grzemich 0:d7bd7384a37c 427 grow = new_len - p->tot_len;
grzemich 0:d7bd7384a37c 428
grzemich 0:d7bd7384a37c 429 /* first, step over any pbufs that should remain in the chain */
grzemich 0:d7bd7384a37c 430 rem_len = new_len;
grzemich 0:d7bd7384a37c 431 q = p;
grzemich 0:d7bd7384a37c 432 /* should this pbuf be kept? */
grzemich 0:d7bd7384a37c 433 while (rem_len > q->len) {
grzemich 0:d7bd7384a37c 434 /* decrease remaining length by pbuf length */
grzemich 0:d7bd7384a37c 435 rem_len -= q->len;
grzemich 0:d7bd7384a37c 436 /* decrease total length indicator */
grzemich 0:d7bd7384a37c 437 LWIP_ASSERT("grow < max_u16_t", grow < 0xffff);
grzemich 0:d7bd7384a37c 438 q->tot_len += (u16_t)grow;
grzemich 0:d7bd7384a37c 439 /* proceed to next pbuf in chain */
grzemich 0:d7bd7384a37c 440 q = q->next;
grzemich 0:d7bd7384a37c 441 LWIP_ASSERT("pbuf_realloc: q != NULL", q != NULL);
grzemich 0:d7bd7384a37c 442 }
grzemich 0:d7bd7384a37c 443 /* we have now reached the new last pbuf (in q) */
grzemich 0:d7bd7384a37c 444 /* rem_len == desired length for pbuf q */
grzemich 0:d7bd7384a37c 445
grzemich 0:d7bd7384a37c 446 /* shrink allocated memory for PBUF_RAM */
grzemich 0:d7bd7384a37c 447 /* (other types merely adjust their length fields */
grzemich 0:d7bd7384a37c 448 if ((q->type == PBUF_RAM) && (rem_len != q->len)) {
grzemich 0:d7bd7384a37c 449 /* reallocate and adjust the length of the pbuf that will be split */
grzemich 0:d7bd7384a37c 450 q = (struct pbuf *)mem_trim(q, (u16_t)((u8_t *)q->payload - (u8_t *)q) + rem_len);
grzemich 0:d7bd7384a37c 451 LWIP_ASSERT("mem_trim returned q == NULL", q != NULL);
grzemich 0:d7bd7384a37c 452 }
grzemich 0:d7bd7384a37c 453 /* adjust length fields for new last pbuf */
grzemich 0:d7bd7384a37c 454 q->len = rem_len;
grzemich 0:d7bd7384a37c 455 q->tot_len = q->len;
grzemich 0:d7bd7384a37c 456
grzemich 0:d7bd7384a37c 457 /* any remaining pbufs in chain? */
grzemich 0:d7bd7384a37c 458 if (q->next != NULL) {
grzemich 0:d7bd7384a37c 459 /* free remaining pbufs in chain */
grzemich 0:d7bd7384a37c 460 pbuf_free(q->next);
grzemich 0:d7bd7384a37c 461 }
grzemich 0:d7bd7384a37c 462 /* q is last packet in chain */
grzemich 0:d7bd7384a37c 463 q->next = NULL;
grzemich 0:d7bd7384a37c 464
grzemich 0:d7bd7384a37c 465 }
grzemich 0:d7bd7384a37c 466
grzemich 0:d7bd7384a37c 467 /**
grzemich 0:d7bd7384a37c 468 * Adjusts the payload pointer to hide or reveal headers in the payload.
grzemich 0:d7bd7384a37c 469 *
grzemich 0:d7bd7384a37c 470 * Adjusts the ->payload pointer so that space for a header
grzemich 0:d7bd7384a37c 471 * (dis)appears in the pbuf payload.
grzemich 0:d7bd7384a37c 472 *
grzemich 0:d7bd7384a37c 473 * The ->payload, ->tot_len and ->len fields are adjusted.
grzemich 0:d7bd7384a37c 474 *
grzemich 0:d7bd7384a37c 475 * @param p pbuf to change the header size.
grzemich 0:d7bd7384a37c 476 * @param header_size_increment Number of bytes to increment header size which
grzemich 0:d7bd7384a37c 477 * increases the size of the pbuf. New space is on the front.
grzemich 0:d7bd7384a37c 478 * (Using a negative value decreases the header size.)
grzemich 0:d7bd7384a37c 479 * If hdr_size_inc is 0, this function does nothing and returns succesful.
grzemich 0:d7bd7384a37c 480 *
grzemich 0:d7bd7384a37c 481 * PBUF_ROM and PBUF_REF type buffers cannot have their sizes increased, so
grzemich 0:d7bd7384a37c 482 * the call will fail. A check is made that the increase in header size does
grzemich 0:d7bd7384a37c 483 * not move the payload pointer in front of the start of the buffer.
grzemich 0:d7bd7384a37c 484 * @return non-zero on failure, zero on success.
grzemich 0:d7bd7384a37c 485 *
grzemich 0:d7bd7384a37c 486 */
grzemich 0:d7bd7384a37c 487 u8_t
grzemich 0:d7bd7384a37c 488 pbuf_header(struct pbuf *p, s16_t header_size_increment)
grzemich 0:d7bd7384a37c 489 {
grzemich 0:d7bd7384a37c 490 u16_t type;
grzemich 0:d7bd7384a37c 491 void *payload;
grzemich 0:d7bd7384a37c 492 u16_t increment_magnitude;
grzemich 0:d7bd7384a37c 493
grzemich 0:d7bd7384a37c 494 LWIP_ASSERT("p != NULL", p != NULL);
grzemich 0:d7bd7384a37c 495 if ((header_size_increment == 0) || (p == NULL)) {
grzemich 0:d7bd7384a37c 496 return 0;
grzemich 0:d7bd7384a37c 497 }
grzemich 0:d7bd7384a37c 498
grzemich 0:d7bd7384a37c 499 if (header_size_increment < 0){
grzemich 0:d7bd7384a37c 500 increment_magnitude = -header_size_increment;
grzemich 0:d7bd7384a37c 501 /* Check that we aren't going to move off the end of the pbuf */
grzemich 0:d7bd7384a37c 502 LWIP_ERROR("increment_magnitude <= p->len", (increment_magnitude <= p->len), return 1;);
grzemich 0:d7bd7384a37c 503 } else {
grzemich 0:d7bd7384a37c 504 increment_magnitude = header_size_increment;
grzemich 0:d7bd7384a37c 505 #if 0
grzemich 0:d7bd7384a37c 506 /* Can't assert these as some callers speculatively call
grzemich 0:d7bd7384a37c 507 pbuf_header() to see if it's OK. Will return 1 below instead. */
grzemich 0:d7bd7384a37c 508 /* Check that we've got the correct type of pbuf to work with */
grzemich 0:d7bd7384a37c 509 LWIP_ASSERT("p->type == PBUF_RAM || p->type == PBUF_POOL",
grzemich 0:d7bd7384a37c 510 p->type == PBUF_RAM || p->type == PBUF_POOL);
grzemich 0:d7bd7384a37c 511 /* Check that we aren't going to move off the beginning of the pbuf */
grzemich 0:d7bd7384a37c 512 LWIP_ASSERT("p->payload - increment_magnitude >= p + SIZEOF_STRUCT_PBUF",
grzemich 0:d7bd7384a37c 513 (u8_t *)p->payload - increment_magnitude >= (u8_t *)p + SIZEOF_STRUCT_PBUF);
grzemich 0:d7bd7384a37c 514 #endif
grzemich 0:d7bd7384a37c 515 }
grzemich 0:d7bd7384a37c 516
grzemich 0:d7bd7384a37c 517 type = p->type;
grzemich 0:d7bd7384a37c 518 /* remember current payload pointer */
grzemich 0:d7bd7384a37c 519 payload = p->payload;
grzemich 0:d7bd7384a37c 520
grzemich 0:d7bd7384a37c 521 /* pbuf types containing payloads? */
grzemich 0:d7bd7384a37c 522 if (type == PBUF_RAM || type == PBUF_POOL) {
grzemich 0:d7bd7384a37c 523 /* set new payload pointer */
grzemich 0:d7bd7384a37c 524 p->payload = (u8_t *)p->payload - header_size_increment;
grzemich 0:d7bd7384a37c 525 /* boundary check fails? */
grzemich 0:d7bd7384a37c 526 if ((u8_t *)p->payload < (u8_t *)p + SIZEOF_STRUCT_PBUF) {
grzemich 0:d7bd7384a37c 527 LWIP_DEBUGF( PBUF_DEBUG | LWIP_DBG_LEVEL_SERIOUS,
grzemich 0:d7bd7384a37c 528 ("pbuf_header: failed as %p < %p (not enough space for new header size)\n",
grzemich 0:d7bd7384a37c 529 (void *)p->payload, (void *)(p + 1)));
grzemich 0:d7bd7384a37c 530 /* restore old payload pointer */
grzemich 0:d7bd7384a37c 531 p->payload = payload;
grzemich 0:d7bd7384a37c 532 /* bail out unsuccesfully */
grzemich 0:d7bd7384a37c 533 return 1;
grzemich 0:d7bd7384a37c 534 }
grzemich 0:d7bd7384a37c 535 /* pbuf types refering to external payloads? */
grzemich 0:d7bd7384a37c 536 } else if (type == PBUF_REF || type == PBUF_ROM) {
grzemich 0:d7bd7384a37c 537 /* hide a header in the payload? */
grzemich 0:d7bd7384a37c 538 if ((header_size_increment < 0) && (increment_magnitude <= p->len)) {
grzemich 0:d7bd7384a37c 539 /* increase payload pointer */
grzemich 0:d7bd7384a37c 540 p->payload = (u8_t *)p->payload - header_size_increment;
grzemich 0:d7bd7384a37c 541 } else {
grzemich 0:d7bd7384a37c 542 /* cannot expand payload to front (yet!)
grzemich 0:d7bd7384a37c 543 * bail out unsuccesfully */
grzemich 0:d7bd7384a37c 544 return 1;
grzemich 0:d7bd7384a37c 545 }
grzemich 0:d7bd7384a37c 546 } else {
grzemich 0:d7bd7384a37c 547 /* Unknown type */
grzemich 0:d7bd7384a37c 548 LWIP_ASSERT("bad pbuf type", 0);
grzemich 0:d7bd7384a37c 549 return 1;
grzemich 0:d7bd7384a37c 550 }
grzemich 0:d7bd7384a37c 551 /* modify pbuf length fields */
grzemich 0:d7bd7384a37c 552 p->len += header_size_increment;
grzemich 0:d7bd7384a37c 553 p->tot_len += header_size_increment;
grzemich 0:d7bd7384a37c 554
grzemich 0:d7bd7384a37c 555 LWIP_DEBUGF(PBUF_DEBUG | LWIP_DBG_TRACE, ("pbuf_header: old %p new %p (%"S16_F")\n",
grzemich 0:d7bd7384a37c 556 (void *)payload, (void *)p->payload, header_size_increment));
grzemich 0:d7bd7384a37c 557
grzemich 0:d7bd7384a37c 558 return 0;
grzemich 0:d7bd7384a37c 559 }
grzemich 0:d7bd7384a37c 560
grzemich 0:d7bd7384a37c 561 /**
grzemich 0:d7bd7384a37c 562 * Dereference a pbuf chain or queue and deallocate any no-longer-used
grzemich 0:d7bd7384a37c 563 * pbufs at the head of this chain or queue.
grzemich 0:d7bd7384a37c 564 *
grzemich 0:d7bd7384a37c 565 * Decrements the pbuf reference count. If it reaches zero, the pbuf is
grzemich 0:d7bd7384a37c 566 * deallocated.
grzemich 0:d7bd7384a37c 567 *
grzemich 0:d7bd7384a37c 568 * For a pbuf chain, this is repeated for each pbuf in the chain,
grzemich 0:d7bd7384a37c 569 * up to the first pbuf which has a non-zero reference count after
grzemich 0:d7bd7384a37c 570 * decrementing. So, when all reference counts are one, the whole
grzemich 0:d7bd7384a37c 571 * chain is free'd.
grzemich 0:d7bd7384a37c 572 *
grzemich 0:d7bd7384a37c 573 * @param p The pbuf (chain) to be dereferenced.
grzemich 0:d7bd7384a37c 574 *
grzemich 0:d7bd7384a37c 575 * @return the number of pbufs that were de-allocated
grzemich 0:d7bd7384a37c 576 * from the head of the chain.
grzemich 0:d7bd7384a37c 577 *
grzemich 0:d7bd7384a37c 578 * @note MUST NOT be called on a packet queue (Not verified to work yet).
grzemich 0:d7bd7384a37c 579 * @note the reference counter of a pbuf equals the number of pointers
grzemich 0:d7bd7384a37c 580 * that refer to the pbuf (or into the pbuf).
grzemich 0:d7bd7384a37c 581 *
grzemich 0:d7bd7384a37c 582 * @internal examples:
grzemich 0:d7bd7384a37c 583 *
grzemich 0:d7bd7384a37c 584 * Assuming existing chains a->b->c with the following reference
grzemich 0:d7bd7384a37c 585 * counts, calling pbuf_free(a) results in:
grzemich 0:d7bd7384a37c 586 *
grzemich 0:d7bd7384a37c 587 * 1->2->3 becomes ...1->3
grzemich 0:d7bd7384a37c 588 * 3->3->3 becomes 2->3->3
grzemich 0:d7bd7384a37c 589 * 1->1->2 becomes ......1
grzemich 0:d7bd7384a37c 590 * 2->1->1 becomes 1->1->1
grzemich 0:d7bd7384a37c 591 * 1->1->1 becomes .......
grzemich 0:d7bd7384a37c 592 *
grzemich 0:d7bd7384a37c 593 */
grzemich 0:d7bd7384a37c 594 u8_t
grzemich 0:d7bd7384a37c 595 pbuf_free(struct pbuf *p)
grzemich 0:d7bd7384a37c 596 {
grzemich 0:d7bd7384a37c 597 u16_t type;
grzemich 0:d7bd7384a37c 598 struct pbuf *q;
grzemich 0:d7bd7384a37c 599 u8_t count;
grzemich 0:d7bd7384a37c 600
grzemich 0:d7bd7384a37c 601 if (p == NULL) {
grzemich 0:d7bd7384a37c 602 LWIP_ASSERT("p != NULL", p != NULL);
grzemich 0:d7bd7384a37c 603 /* if assertions are disabled, proceed with debug output */
grzemich 0:d7bd7384a37c 604 LWIP_DEBUGF(PBUF_DEBUG | LWIP_DBG_LEVEL_SERIOUS,
grzemich 0:d7bd7384a37c 605 ("pbuf_free(p == NULL) was called.\n"));
grzemich 0:d7bd7384a37c 606 return 0;
grzemich 0:d7bd7384a37c 607 }
grzemich 0:d7bd7384a37c 608 LWIP_DEBUGF(PBUF_DEBUG | LWIP_DBG_TRACE, ("pbuf_free(%p)\n", (void *)p));
grzemich 0:d7bd7384a37c 609
grzemich 0:d7bd7384a37c 610 PERF_START;
grzemich 0:d7bd7384a37c 611
grzemich 0:d7bd7384a37c 612 LWIP_ASSERT("pbuf_free: sane type",
grzemich 0:d7bd7384a37c 613 p->type == PBUF_RAM || p->type == PBUF_ROM ||
grzemich 0:d7bd7384a37c 614 p->type == PBUF_REF || p->type == PBUF_POOL);
grzemich 0:d7bd7384a37c 615
grzemich 0:d7bd7384a37c 616 count = 0;
grzemich 0:d7bd7384a37c 617 /* de-allocate all consecutive pbufs from the head of the chain that
grzemich 0:d7bd7384a37c 618 * obtain a zero reference count after decrementing*/
grzemich 0:d7bd7384a37c 619 while (p != NULL) {
grzemich 0:d7bd7384a37c 620 u16_t ref;
grzemich 0:d7bd7384a37c 621 SYS_ARCH_DECL_PROTECT(old_level);
grzemich 0:d7bd7384a37c 622 /* Since decrementing ref cannot be guaranteed to be a single machine operation
grzemich 0:d7bd7384a37c 623 * we must protect it. We put the new ref into a local variable to prevent
grzemich 0:d7bd7384a37c 624 * further protection. */
grzemich 0:d7bd7384a37c 625 SYS_ARCH_PROTECT(old_level);
grzemich 0:d7bd7384a37c 626 /* all pbufs in a chain are referenced at least once */
grzemich 0:d7bd7384a37c 627 LWIP_ASSERT("pbuf_free: p->ref > 0", p->ref > 0);
grzemich 0:d7bd7384a37c 628 /* decrease reference count (number of pointers to pbuf) */
grzemich 0:d7bd7384a37c 629 ref = --(p->ref);
grzemich 0:d7bd7384a37c 630 SYS_ARCH_UNPROTECT(old_level);
grzemich 0:d7bd7384a37c 631 /* this pbuf is no longer referenced to? */
grzemich 0:d7bd7384a37c 632 if (ref == 0) {
grzemich 0:d7bd7384a37c 633 /* remember next pbuf in chain for next iteration */
grzemich 0:d7bd7384a37c 634 q = p->next;
grzemich 0:d7bd7384a37c 635 LWIP_DEBUGF( PBUF_DEBUG | LWIP_DBG_TRACE, ("pbuf_free: deallocating %p\n", (void *)p));
grzemich 0:d7bd7384a37c 636 type = p->type;
grzemich 0:d7bd7384a37c 637 #if LWIP_SUPPORT_CUSTOM_PBUF
grzemich 0:d7bd7384a37c 638 /* is this a custom pbuf? */
grzemich 0:d7bd7384a37c 639 if ((p->flags & PBUF_FLAG_IS_CUSTOM) != 0) {
grzemich 0:d7bd7384a37c 640 struct pbuf_custom *pc = (struct pbuf_custom*)p;
grzemich 0:d7bd7384a37c 641 LWIP_ASSERT("pc->custom_free_function != NULL", pc->custom_free_function != NULL);
grzemich 0:d7bd7384a37c 642 pc->custom_free_function(p);
grzemich 0:d7bd7384a37c 643 } else
grzemich 0:d7bd7384a37c 644 #endif /* LWIP_SUPPORT_CUSTOM_PBUF */
grzemich 0:d7bd7384a37c 645 {
grzemich 0:d7bd7384a37c 646 /* is this a pbuf from the pool? */
grzemich 0:d7bd7384a37c 647 if (type == PBUF_POOL) {
grzemich 0:d7bd7384a37c 648 memp_free(MEMP_PBUF_POOL, p);
grzemich 0:d7bd7384a37c 649 /* is this a ROM or RAM referencing pbuf? */
grzemich 0:d7bd7384a37c 650 } else if (type == PBUF_ROM || type == PBUF_REF) {
grzemich 0:d7bd7384a37c 651 memp_free(MEMP_PBUF, p);
grzemich 0:d7bd7384a37c 652 /* type == PBUF_RAM */
grzemich 0:d7bd7384a37c 653 } else {
grzemich 0:d7bd7384a37c 654 mem_free(p);
grzemich 0:d7bd7384a37c 655 }
grzemich 0:d7bd7384a37c 656 }
grzemich 0:d7bd7384a37c 657 count++;
grzemich 0:d7bd7384a37c 658 /* proceed to next pbuf */
grzemich 0:d7bd7384a37c 659 p = q;
grzemich 0:d7bd7384a37c 660 /* p->ref > 0, this pbuf is still referenced to */
grzemich 0:d7bd7384a37c 661 /* (and so the remaining pbufs in chain as well) */
grzemich 0:d7bd7384a37c 662 } else {
grzemich 0:d7bd7384a37c 663 LWIP_DEBUGF( PBUF_DEBUG | LWIP_DBG_TRACE, ("pbuf_free: %p has ref %"U16_F", ending here.\n", (void *)p, ref));
grzemich 0:d7bd7384a37c 664 /* stop walking through the chain */
grzemich 0:d7bd7384a37c 665 p = NULL;
grzemich 0:d7bd7384a37c 666 }
grzemich 0:d7bd7384a37c 667 }
grzemich 0:d7bd7384a37c 668 PERF_STOP("pbuf_free");
grzemich 0:d7bd7384a37c 669 /* return number of de-allocated pbufs */
grzemich 0:d7bd7384a37c 670 return count;
grzemich 0:d7bd7384a37c 671 }
grzemich 0:d7bd7384a37c 672
grzemich 0:d7bd7384a37c 673 /**
grzemich 0:d7bd7384a37c 674 * Count number of pbufs in a chain
grzemich 0:d7bd7384a37c 675 *
grzemich 0:d7bd7384a37c 676 * @param p first pbuf of chain
grzemich 0:d7bd7384a37c 677 * @return the number of pbufs in a chain
grzemich 0:d7bd7384a37c 678 */
grzemich 0:d7bd7384a37c 679
grzemich 0:d7bd7384a37c 680 u8_t
grzemich 0:d7bd7384a37c 681 pbuf_clen(struct pbuf *p)
grzemich 0:d7bd7384a37c 682 {
grzemich 0:d7bd7384a37c 683 u8_t len;
grzemich 0:d7bd7384a37c 684
grzemich 0:d7bd7384a37c 685 len = 0;
grzemich 0:d7bd7384a37c 686 while (p != NULL) {
grzemich 0:d7bd7384a37c 687 ++len;
grzemich 0:d7bd7384a37c 688 p = p->next;
grzemich 0:d7bd7384a37c 689 }
grzemich 0:d7bd7384a37c 690 return len;
grzemich 0:d7bd7384a37c 691 }
grzemich 0:d7bd7384a37c 692
grzemich 0:d7bd7384a37c 693 /**
grzemich 0:d7bd7384a37c 694 * Increment the reference count of the pbuf.
grzemich 0:d7bd7384a37c 695 *
grzemich 0:d7bd7384a37c 696 * @param p pbuf to increase reference counter of
grzemich 0:d7bd7384a37c 697 *
grzemich 0:d7bd7384a37c 698 */
grzemich 0:d7bd7384a37c 699 void
grzemich 0:d7bd7384a37c 700 pbuf_ref(struct pbuf *p)
grzemich 0:d7bd7384a37c 701 {
grzemich 0:d7bd7384a37c 702 SYS_ARCH_DECL_PROTECT(old_level);
grzemich 0:d7bd7384a37c 703 /* pbuf given? */
grzemich 0:d7bd7384a37c 704 if (p != NULL) {
grzemich 0:d7bd7384a37c 705 SYS_ARCH_PROTECT(old_level);
grzemich 0:d7bd7384a37c 706 ++(p->ref);
grzemich 0:d7bd7384a37c 707 SYS_ARCH_UNPROTECT(old_level);
grzemich 0:d7bd7384a37c 708 }
grzemich 0:d7bd7384a37c 709 }
grzemich 0:d7bd7384a37c 710
grzemich 0:d7bd7384a37c 711 /**
grzemich 0:d7bd7384a37c 712 * Concatenate two pbufs (each may be a pbuf chain) and take over
grzemich 0:d7bd7384a37c 713 * the caller's reference of the tail pbuf.
grzemich 0:d7bd7384a37c 714 *
grzemich 0:d7bd7384a37c 715 * @note The caller MAY NOT reference the tail pbuf afterwards.
grzemich 0:d7bd7384a37c 716 * Use pbuf_chain() for that purpose.
grzemich 0:d7bd7384a37c 717 *
grzemich 0:d7bd7384a37c 718 * @see pbuf_chain()
grzemich 0:d7bd7384a37c 719 */
grzemich 0:d7bd7384a37c 720
grzemich 0:d7bd7384a37c 721 void
grzemich 0:d7bd7384a37c 722 pbuf_cat(struct pbuf *h, struct pbuf *t)
grzemich 0:d7bd7384a37c 723 {
grzemich 0:d7bd7384a37c 724 struct pbuf *p;
grzemich 0:d7bd7384a37c 725
grzemich 0:d7bd7384a37c 726 LWIP_ERROR("(h != NULL) && (t != NULL) (programmer violates API)",
grzemich 0:d7bd7384a37c 727 ((h != NULL) && (t != NULL)), return;);
grzemich 0:d7bd7384a37c 728
grzemich 0:d7bd7384a37c 729 /* proceed to last pbuf of chain */
grzemich 0:d7bd7384a37c 730 for (p = h; p->next != NULL; p = p->next) {
grzemich 0:d7bd7384a37c 731 /* add total length of second chain to all totals of first chain */
grzemich 0:d7bd7384a37c 732 p->tot_len += t->tot_len;
grzemich 0:d7bd7384a37c 733 }
grzemich 0:d7bd7384a37c 734 /* { p is last pbuf of first h chain, p->next == NULL } */
grzemich 0:d7bd7384a37c 735 LWIP_ASSERT("p->tot_len == p->len (of last pbuf in chain)", p->tot_len == p->len);
grzemich 0:d7bd7384a37c 736 LWIP_ASSERT("p->next == NULL", p->next == NULL);
grzemich 0:d7bd7384a37c 737 /* add total length of second chain to last pbuf total of first chain */
grzemich 0:d7bd7384a37c 738 p->tot_len += t->tot_len;
grzemich 0:d7bd7384a37c 739 /* chain last pbuf of head (p) with first of tail (t) */
grzemich 0:d7bd7384a37c 740 p->next = t;
grzemich 0:d7bd7384a37c 741 /* p->next now references t, but the caller will drop its reference to t,
grzemich 0:d7bd7384a37c 742 * so netto there is no change to the reference count of t.
grzemich 0:d7bd7384a37c 743 */
grzemich 0:d7bd7384a37c 744 }
grzemich 0:d7bd7384a37c 745
grzemich 0:d7bd7384a37c 746 /**
grzemich 0:d7bd7384a37c 747 * Chain two pbufs (or pbuf chains) together.
grzemich 0:d7bd7384a37c 748 *
grzemich 0:d7bd7384a37c 749 * The caller MUST call pbuf_free(t) once it has stopped
grzemich 0:d7bd7384a37c 750 * using it. Use pbuf_cat() instead if you no longer use t.
grzemich 0:d7bd7384a37c 751 *
grzemich 0:d7bd7384a37c 752 * @param h head pbuf (chain)
grzemich 0:d7bd7384a37c 753 * @param t tail pbuf (chain)
grzemich 0:d7bd7384a37c 754 * @note The pbufs MUST belong to the same packet.
grzemich 0:d7bd7384a37c 755 * @note MAY NOT be called on a packet queue.
grzemich 0:d7bd7384a37c 756 *
grzemich 0:d7bd7384a37c 757 * The ->tot_len fields of all pbufs of the head chain are adjusted.
grzemich 0:d7bd7384a37c 758 * The ->next field of the last pbuf of the head chain is adjusted.
grzemich 0:d7bd7384a37c 759 * The ->ref field of the first pbuf of the tail chain is adjusted.
grzemich 0:d7bd7384a37c 760 *
grzemich 0:d7bd7384a37c 761 */
grzemich 0:d7bd7384a37c 762 void
grzemich 0:d7bd7384a37c 763 pbuf_chain(struct pbuf *h, struct pbuf *t)
grzemich 0:d7bd7384a37c 764 {
grzemich 0:d7bd7384a37c 765 pbuf_cat(h, t);
grzemich 0:d7bd7384a37c 766 /* t is now referenced by h */
grzemich 0:d7bd7384a37c 767 pbuf_ref(t);
grzemich 0:d7bd7384a37c 768 LWIP_DEBUGF(PBUF_DEBUG | LWIP_DBG_TRACE, ("pbuf_chain: %p references %p\n", (void *)h, (void *)t));
grzemich 0:d7bd7384a37c 769 }
grzemich 0:d7bd7384a37c 770
grzemich 0:d7bd7384a37c 771 /**
grzemich 0:d7bd7384a37c 772 * Dechains the first pbuf from its succeeding pbufs in the chain.
grzemich 0:d7bd7384a37c 773 *
grzemich 0:d7bd7384a37c 774 * Makes p->tot_len field equal to p->len.
grzemich 0:d7bd7384a37c 775 * @param p pbuf to dechain
grzemich 0:d7bd7384a37c 776 * @return remainder of the pbuf chain, or NULL if it was de-allocated.
grzemich 0:d7bd7384a37c 777 * @note May not be called on a packet queue.
grzemich 0:d7bd7384a37c 778 */
grzemich 0:d7bd7384a37c 779 struct pbuf *
grzemich 0:d7bd7384a37c 780 pbuf_dechain(struct pbuf *p)
grzemich 0:d7bd7384a37c 781 {
grzemich 0:d7bd7384a37c 782 struct pbuf *q;
grzemich 0:d7bd7384a37c 783 u8_t tail_gone = 1;
grzemich 0:d7bd7384a37c 784 /* tail */
grzemich 0:d7bd7384a37c 785 q = p->next;
grzemich 0:d7bd7384a37c 786 /* pbuf has successor in chain? */
grzemich 0:d7bd7384a37c 787 if (q != NULL) {
grzemich 0:d7bd7384a37c 788 /* assert tot_len invariant: (p->tot_len == p->len + (p->next? p->next->tot_len: 0) */
grzemich 0:d7bd7384a37c 789 LWIP_ASSERT("p->tot_len == p->len + q->tot_len", q->tot_len == p->tot_len - p->len);
grzemich 0:d7bd7384a37c 790 /* enforce invariant if assertion is disabled */
grzemich 0:d7bd7384a37c 791 q->tot_len = p->tot_len - p->len;
grzemich 0:d7bd7384a37c 792 /* decouple pbuf from remainder */
grzemich 0:d7bd7384a37c 793 p->next = NULL;
grzemich 0:d7bd7384a37c 794 /* total length of pbuf p is its own length only */
grzemich 0:d7bd7384a37c 795 p->tot_len = p->len;
grzemich 0:d7bd7384a37c 796 /* q is no longer referenced by p, free it */
grzemich 0:d7bd7384a37c 797 LWIP_DEBUGF(PBUF_DEBUG | LWIP_DBG_TRACE, ("pbuf_dechain: unreferencing %p\n", (void *)q));
grzemich 0:d7bd7384a37c 798 tail_gone = pbuf_free(q);
grzemich 0:d7bd7384a37c 799 if (tail_gone > 0) {
grzemich 0:d7bd7384a37c 800 LWIP_DEBUGF(PBUF_DEBUG | LWIP_DBG_TRACE,
grzemich 0:d7bd7384a37c 801 ("pbuf_dechain: deallocated %p (as it is no longer referenced)\n", (void *)q));
grzemich 0:d7bd7384a37c 802 }
grzemich 0:d7bd7384a37c 803 /* return remaining tail or NULL if deallocated */
grzemich 0:d7bd7384a37c 804 }
grzemich 0:d7bd7384a37c 805 /* assert tot_len invariant: (p->tot_len == p->len + (p->next? p->next->tot_len: 0) */
grzemich 0:d7bd7384a37c 806 LWIP_ASSERT("p->tot_len == p->len", p->tot_len == p->len);
grzemich 0:d7bd7384a37c 807 return ((tail_gone > 0) ? NULL : q);
grzemich 0:d7bd7384a37c 808 }
grzemich 0:d7bd7384a37c 809
grzemich 0:d7bd7384a37c 810 /**
grzemich 0:d7bd7384a37c 811 *
grzemich 0:d7bd7384a37c 812 * Create PBUF_RAM copies of pbufs.
grzemich 0:d7bd7384a37c 813 *
grzemich 0:d7bd7384a37c 814 * Used to queue packets on behalf of the lwIP stack, such as
grzemich 0:d7bd7384a37c 815 * ARP based queueing.
grzemich 0:d7bd7384a37c 816 *
grzemich 0:d7bd7384a37c 817 * @note You MUST explicitly use p = pbuf_take(p);
grzemich 0:d7bd7384a37c 818 *
grzemich 0:d7bd7384a37c 819 * @note Only one packet is copied, no packet queue!
grzemich 0:d7bd7384a37c 820 *
grzemich 0:d7bd7384a37c 821 * @param p_to pbuf destination of the copy
grzemich 0:d7bd7384a37c 822 * @param p_from pbuf source of the copy
grzemich 0:d7bd7384a37c 823 *
grzemich 0:d7bd7384a37c 824 * @return ERR_OK if pbuf was copied
grzemich 0:d7bd7384a37c 825 * ERR_ARG if one of the pbufs is NULL or p_to is not big
grzemich 0:d7bd7384a37c 826 * enough to hold p_from
grzemich 0:d7bd7384a37c 827 */
grzemich 0:d7bd7384a37c 828 err_t
grzemich 0:d7bd7384a37c 829 pbuf_copy(struct pbuf *p_to, struct pbuf *p_from)
grzemich 0:d7bd7384a37c 830 {
grzemich 0:d7bd7384a37c 831 u16_t offset_to=0, offset_from=0, len;
grzemich 0:d7bd7384a37c 832
grzemich 0:d7bd7384a37c 833 LWIP_DEBUGF(PBUF_DEBUG | LWIP_DBG_TRACE, ("pbuf_copy(%p, %p)\n",
grzemich 0:d7bd7384a37c 834 (void*)p_to, (void*)p_from));
grzemich 0:d7bd7384a37c 835
grzemich 0:d7bd7384a37c 836 /* is the target big enough to hold the source? */
grzemich 0:d7bd7384a37c 837 LWIP_ERROR("pbuf_copy: target not big enough to hold source", ((p_to != NULL) &&
grzemich 0:d7bd7384a37c 838 (p_from != NULL) && (p_to->tot_len >= p_from->tot_len)), return ERR_ARG;);
grzemich 0:d7bd7384a37c 839
grzemich 0:d7bd7384a37c 840 /* iterate through pbuf chain */
grzemich 0:d7bd7384a37c 841 do
grzemich 0:d7bd7384a37c 842 {
grzemich 0:d7bd7384a37c 843 LWIP_ASSERT("p_to != NULL", p_to != NULL);
grzemich 0:d7bd7384a37c 844 /* copy one part of the original chain */
grzemich 0:d7bd7384a37c 845 if ((p_to->len - offset_to) >= (p_from->len - offset_from)) {
grzemich 0:d7bd7384a37c 846 /* complete current p_from fits into current p_to */
grzemich 0:d7bd7384a37c 847 len = p_from->len - offset_from;
grzemich 0:d7bd7384a37c 848 } else {
grzemich 0:d7bd7384a37c 849 /* current p_from does not fit into current p_to */
grzemich 0:d7bd7384a37c 850 len = p_to->len - offset_to;
grzemich 0:d7bd7384a37c 851 }
grzemich 0:d7bd7384a37c 852 MEMCPY((u8_t*)p_to->payload + offset_to, (u8_t*)p_from->payload + offset_from, len);
grzemich 0:d7bd7384a37c 853 offset_to += len;
grzemich 0:d7bd7384a37c 854 offset_from += len;
grzemich 0:d7bd7384a37c 855 LWIP_ASSERT("offset_to <= p_to->len", offset_to <= p_to->len);
grzemich 0:d7bd7384a37c 856 if (offset_to == p_to->len) {
grzemich 0:d7bd7384a37c 857 /* on to next p_to (if any) */
grzemich 0:d7bd7384a37c 858 offset_to = 0;
grzemich 0:d7bd7384a37c 859 p_to = p_to->next;
grzemich 0:d7bd7384a37c 860 }
grzemich 0:d7bd7384a37c 861 LWIP_ASSERT("offset_from <= p_from->len", offset_from <= p_from->len);
grzemich 0:d7bd7384a37c 862 if (offset_from >= p_from->len) {
grzemich 0:d7bd7384a37c 863 /* on to next p_from (if any) */
grzemich 0:d7bd7384a37c 864 offset_from = 0;
grzemich 0:d7bd7384a37c 865 p_from = p_from->next;
grzemich 0:d7bd7384a37c 866 }
grzemich 0:d7bd7384a37c 867
grzemich 0:d7bd7384a37c 868 if((p_from != NULL) && (p_from->len == p_from->tot_len)) {
grzemich 0:d7bd7384a37c 869 /* don't copy more than one packet! */
grzemich 0:d7bd7384a37c 870 LWIP_ERROR("pbuf_copy() does not allow packet queues!\n",
grzemich 0:d7bd7384a37c 871 (p_from->next == NULL), return ERR_VAL;);
grzemich 0:d7bd7384a37c 872 }
grzemich 0:d7bd7384a37c 873 if((p_to != NULL) && (p_to->len == p_to->tot_len)) {
grzemich 0:d7bd7384a37c 874 /* don't copy more than one packet! */
grzemich 0:d7bd7384a37c 875 LWIP_ERROR("pbuf_copy() does not allow packet queues!\n",
grzemich 0:d7bd7384a37c 876 (p_to->next == NULL), return ERR_VAL;);
grzemich 0:d7bd7384a37c 877 }
grzemich 0:d7bd7384a37c 878 } while (p_from);
grzemich 0:d7bd7384a37c 879 LWIP_DEBUGF(PBUF_DEBUG | LWIP_DBG_TRACE, ("pbuf_copy: end of chain reached.\n"));
grzemich 0:d7bd7384a37c 880 return ERR_OK;
grzemich 0:d7bd7384a37c 881 }
grzemich 0:d7bd7384a37c 882
grzemich 0:d7bd7384a37c 883 /**
grzemich 0:d7bd7384a37c 884 * Copy (part of) the contents of a packet buffer
grzemich 0:d7bd7384a37c 885 * to an application supplied buffer.
grzemich 0:d7bd7384a37c 886 *
grzemich 0:d7bd7384a37c 887 * @param buf the pbuf from which to copy data
grzemich 0:d7bd7384a37c 888 * @param dataptr the application supplied buffer
grzemich 0:d7bd7384a37c 889 * @param len length of data to copy (dataptr must be big enough). No more
grzemich 0:d7bd7384a37c 890 * than buf->tot_len will be copied, irrespective of len
grzemich 0:d7bd7384a37c 891 * @param offset offset into the packet buffer from where to begin copying len bytes
grzemich 0:d7bd7384a37c 892 * @return the number of bytes copied, or 0 on failure
grzemich 0:d7bd7384a37c 893 */
grzemich 0:d7bd7384a37c 894 u16_t
grzemich 0:d7bd7384a37c 895 pbuf_copy_partial(struct pbuf *buf, void *dataptr, u16_t len, u16_t offset)
grzemich 0:d7bd7384a37c 896 {
grzemich 0:d7bd7384a37c 897 struct pbuf *p;
grzemich 0:d7bd7384a37c 898 u16_t left;
grzemich 0:d7bd7384a37c 899 u16_t buf_copy_len;
grzemich 0:d7bd7384a37c 900 u16_t copied_total = 0;
grzemich 0:d7bd7384a37c 901
grzemich 0:d7bd7384a37c 902 LWIP_ERROR("pbuf_copy_partial: invalid buf", (buf != NULL), return 0;);
grzemich 0:d7bd7384a37c 903 LWIP_ERROR("pbuf_copy_partial: invalid dataptr", (dataptr != NULL), return 0;);
grzemich 0:d7bd7384a37c 904
grzemich 0:d7bd7384a37c 905 left = 0;
grzemich 0:d7bd7384a37c 906
grzemich 0:d7bd7384a37c 907 if((buf == NULL) || (dataptr == NULL)) {
grzemich 0:d7bd7384a37c 908 return 0;
grzemich 0:d7bd7384a37c 909 }
grzemich 0:d7bd7384a37c 910
grzemich 0:d7bd7384a37c 911 /* Note some systems use byte copy if dataptr or one of the pbuf payload pointers are unaligned. */
grzemich 0:d7bd7384a37c 912 for(p = buf; len != 0 && p != NULL; p = p->next) {
grzemich 0:d7bd7384a37c 913 if ((offset != 0) && (offset >= p->len)) {
grzemich 0:d7bd7384a37c 914 /* don't copy from this buffer -> on to the next */
grzemich 0:d7bd7384a37c 915 offset -= p->len;
grzemich 0:d7bd7384a37c 916 } else {
grzemich 0:d7bd7384a37c 917 /* copy from this buffer. maybe only partially. */
grzemich 0:d7bd7384a37c 918 buf_copy_len = p->len - offset;
grzemich 0:d7bd7384a37c 919 if (buf_copy_len > len)
grzemich 0:d7bd7384a37c 920 buf_copy_len = len;
grzemich 0:d7bd7384a37c 921 /* copy the necessary parts of the buffer */
grzemich 0:d7bd7384a37c 922 MEMCPY(&((char*)dataptr)[left], &((char*)p->payload)[offset], buf_copy_len);
grzemich 0:d7bd7384a37c 923 copied_total += buf_copy_len;
grzemich 0:d7bd7384a37c 924 left += buf_copy_len;
grzemich 0:d7bd7384a37c 925 len -= buf_copy_len;
grzemich 0:d7bd7384a37c 926 offset = 0;
grzemich 0:d7bd7384a37c 927 }
grzemich 0:d7bd7384a37c 928 }
grzemich 0:d7bd7384a37c 929 return copied_total;
grzemich 0:d7bd7384a37c 930 }
grzemich 0:d7bd7384a37c 931
grzemich 0:d7bd7384a37c 932 /**
grzemich 0:d7bd7384a37c 933 * Copy application supplied data into a pbuf.
grzemich 0:d7bd7384a37c 934 * This function can only be used to copy the equivalent of buf->tot_len data.
grzemich 0:d7bd7384a37c 935 *
grzemich 0:d7bd7384a37c 936 * @param buf pbuf to fill with data
grzemich 0:d7bd7384a37c 937 * @param dataptr application supplied data buffer
grzemich 0:d7bd7384a37c 938 * @param len length of the application supplied data buffer
grzemich 0:d7bd7384a37c 939 *
grzemich 0:d7bd7384a37c 940 * @return ERR_OK if successful, ERR_MEM if the pbuf is not big enough
grzemich 0:d7bd7384a37c 941 */
grzemich 0:d7bd7384a37c 942 err_t
grzemich 0:d7bd7384a37c 943 pbuf_take(struct pbuf *buf, const void *dataptr, u16_t len)
grzemich 0:d7bd7384a37c 944 {
grzemich 0:d7bd7384a37c 945 struct pbuf *p;
grzemich 0:d7bd7384a37c 946 u16_t buf_copy_len;
grzemich 0:d7bd7384a37c 947 u16_t total_copy_len = len;
grzemich 0:d7bd7384a37c 948 u16_t copied_total = 0;
grzemich 0:d7bd7384a37c 949
grzemich 0:d7bd7384a37c 950 LWIP_ERROR("pbuf_take: invalid buf", (buf != NULL), return 0;);
grzemich 0:d7bd7384a37c 951 LWIP_ERROR("pbuf_take: invalid dataptr", (dataptr != NULL), return 0;);
grzemich 0:d7bd7384a37c 952
grzemich 0:d7bd7384a37c 953 if ((buf == NULL) || (dataptr == NULL) || (buf->tot_len < len)) {
grzemich 0:d7bd7384a37c 954 return ERR_ARG;
grzemich 0:d7bd7384a37c 955 }
grzemich 0:d7bd7384a37c 956
grzemich 0:d7bd7384a37c 957 /* Note some systems use byte copy if dataptr or one of the pbuf payload pointers are unaligned. */
grzemich 0:d7bd7384a37c 958 for(p = buf; total_copy_len != 0; p = p->next) {
grzemich 0:d7bd7384a37c 959 LWIP_ASSERT("pbuf_take: invalid pbuf", p != NULL);
grzemich 0:d7bd7384a37c 960 buf_copy_len = total_copy_len;
grzemich 0:d7bd7384a37c 961 if (buf_copy_len > p->len) {
grzemich 0:d7bd7384a37c 962 /* this pbuf cannot hold all remaining data */
grzemich 0:d7bd7384a37c 963 buf_copy_len = p->len;
grzemich 0:d7bd7384a37c 964 }
grzemich 0:d7bd7384a37c 965 /* copy the necessary parts of the buffer */
grzemich 0:d7bd7384a37c 966 MEMCPY(p->payload, &((char*)dataptr)[copied_total], buf_copy_len);
grzemich 0:d7bd7384a37c 967 total_copy_len -= buf_copy_len;
grzemich 0:d7bd7384a37c 968 copied_total += buf_copy_len;
grzemich 0:d7bd7384a37c 969 }
grzemich 0:d7bd7384a37c 970 LWIP_ASSERT("did not copy all data", total_copy_len == 0 && copied_total == len);
grzemich 0:d7bd7384a37c 971 return ERR_OK;
grzemich 0:d7bd7384a37c 972 }
grzemich 0:d7bd7384a37c 973
grzemich 0:d7bd7384a37c 974 /**
grzemich 0:d7bd7384a37c 975 * Creates a single pbuf out of a queue of pbufs.
grzemich 0:d7bd7384a37c 976 *
grzemich 0:d7bd7384a37c 977 * @remark: Either the source pbuf 'p' is freed by this function or the original
grzemich 0:d7bd7384a37c 978 * pbuf 'p' is returned, therefore the caller has to check the result!
grzemich 0:d7bd7384a37c 979 *
grzemich 0:d7bd7384a37c 980 * @param p the source pbuf
grzemich 0:d7bd7384a37c 981 * @param layer pbuf_layer of the new pbuf
grzemich 0:d7bd7384a37c 982 *
grzemich 0:d7bd7384a37c 983 * @return a new, single pbuf (p->next is NULL)
grzemich 0:d7bd7384a37c 984 * or the old pbuf if allocation fails
grzemich 0:d7bd7384a37c 985 */
grzemich 0:d7bd7384a37c 986 struct pbuf*
grzemich 0:d7bd7384a37c 987 pbuf_coalesce(struct pbuf *p, pbuf_layer layer)
grzemich 0:d7bd7384a37c 988 {
grzemich 0:d7bd7384a37c 989 struct pbuf *q;
grzemich 0:d7bd7384a37c 990 err_t err;
grzemich 0:d7bd7384a37c 991 if (p->next == NULL) {
grzemich 0:d7bd7384a37c 992 return p;
grzemich 0:d7bd7384a37c 993 }
grzemich 0:d7bd7384a37c 994 q = pbuf_alloc(layer, p->tot_len, PBUF_RAM);
grzemich 0:d7bd7384a37c 995 if (q == NULL) {
grzemich 0:d7bd7384a37c 996 /* @todo: what do we do now? */
grzemich 0:d7bd7384a37c 997 return p;
grzemich 0:d7bd7384a37c 998 }
grzemich 0:d7bd7384a37c 999 err = pbuf_copy(q, p);
grzemich 0:d7bd7384a37c 1000 LWIP_ASSERT("pbuf_copy failed", err == ERR_OK);
grzemich 0:d7bd7384a37c 1001 /* next line references err variable even if LWIP_ASSERT is ignored. */
grzemich 0:d7bd7384a37c 1002 (void)err;
grzemich 0:d7bd7384a37c 1003 pbuf_free(p);
grzemich 0:d7bd7384a37c 1004 return q;
grzemich 0:d7bd7384a37c 1005 }
grzemich 0:d7bd7384a37c 1006
grzemich 0:d7bd7384a37c 1007 #if LWIP_CHECKSUM_ON_COPY
grzemich 0:d7bd7384a37c 1008 /**
grzemich 0:d7bd7384a37c 1009 * Copies data into a single pbuf (*not* into a pbuf queue!) and updates
grzemich 0:d7bd7384a37c 1010 * the checksum while copying
grzemich 0:d7bd7384a37c 1011 *
grzemich 0:d7bd7384a37c 1012 * @param p the pbuf to copy data into
grzemich 0:d7bd7384a37c 1013 * @param start_offset offset of p->payload where to copy the data to
grzemich 0:d7bd7384a37c 1014 * @param dataptr data to copy into the pbuf
grzemich 0:d7bd7384a37c 1015 * @param len length of data to copy into the pbuf
grzemich 0:d7bd7384a37c 1016 * @param chksum pointer to the checksum which is updated
grzemich 0:d7bd7384a37c 1017 * @return ERR_OK if successful, another error if the data does not fit
grzemich 0:d7bd7384a37c 1018 * within the (first) pbuf (no pbuf queues!)
grzemich 0:d7bd7384a37c 1019 */
grzemich 0:d7bd7384a37c 1020 err_t
grzemich 0:d7bd7384a37c 1021 pbuf_fill_chksum(struct pbuf *p, u16_t start_offset, const void *dataptr,
grzemich 0:d7bd7384a37c 1022 u16_t len, u16_t *chksum)
grzemich 0:d7bd7384a37c 1023 {
grzemich 0:d7bd7384a37c 1024 u32_t acc;
grzemich 0:d7bd7384a37c 1025 u16_t copy_chksum;
grzemich 0:d7bd7384a37c 1026 char *dst_ptr;
grzemich 0:d7bd7384a37c 1027 LWIP_ASSERT("p != NULL", p != NULL);
grzemich 0:d7bd7384a37c 1028 LWIP_ASSERT("dataptr != NULL", dataptr != NULL);
grzemich 0:d7bd7384a37c 1029 LWIP_ASSERT("chksum != NULL", chksum != NULL);
grzemich 0:d7bd7384a37c 1030 LWIP_ASSERT("len != 0", len != 0);
grzemich 0:d7bd7384a37c 1031
grzemich 0:d7bd7384a37c 1032 if ((start_offset >= p->len) || (start_offset + len > p->len)) {
grzemich 0:d7bd7384a37c 1033 return ERR_ARG;
grzemich 0:d7bd7384a37c 1034 }
grzemich 0:d7bd7384a37c 1035
grzemich 0:d7bd7384a37c 1036 dst_ptr = ((char*)p->payload) + start_offset;
grzemich 0:d7bd7384a37c 1037 copy_chksum = LWIP_CHKSUM_COPY(dst_ptr, dataptr, len);
grzemich 0:d7bd7384a37c 1038 if ((start_offset & 1) != 0) {
grzemich 0:d7bd7384a37c 1039 copy_chksum = SWAP_BYTES_IN_WORD(copy_chksum);
grzemich 0:d7bd7384a37c 1040 }
grzemich 0:d7bd7384a37c 1041 acc = *chksum;
grzemich 0:d7bd7384a37c 1042 acc += copy_chksum;
grzemich 0:d7bd7384a37c 1043 *chksum = FOLD_U32T(acc);
grzemich 0:d7bd7384a37c 1044 return ERR_OK;
grzemich 0:d7bd7384a37c 1045 }
grzemich 0:d7bd7384a37c 1046 #endif /* LWIP_CHECKSUM_ON_COPY */
grzemich 0:d7bd7384a37c 1047
grzemich 0:d7bd7384a37c 1048 /** Get one byte from the specified position in a pbuf
grzemich 0:d7bd7384a37c 1049 * WARNING: returns zero for offset >= p->tot_len
grzemich 0:d7bd7384a37c 1050 *
grzemich 0:d7bd7384a37c 1051 * @param p pbuf to parse
grzemich 0:d7bd7384a37c 1052 * @param offset offset into p of the byte to return
grzemich 0:d7bd7384a37c 1053 * @return byte at an offset into p OR ZERO IF 'offset' >= p->tot_len
grzemich 0:d7bd7384a37c 1054 */
grzemich 0:d7bd7384a37c 1055 u8_t
grzemich 0:d7bd7384a37c 1056 pbuf_get_at(struct pbuf* p, u16_t offset)
grzemich 0:d7bd7384a37c 1057 {
grzemich 0:d7bd7384a37c 1058 u16_t copy_from = offset;
grzemich 0:d7bd7384a37c 1059 struct pbuf* q = p;
grzemich 0:d7bd7384a37c 1060
grzemich 0:d7bd7384a37c 1061 /* get the correct pbuf */
grzemich 0:d7bd7384a37c 1062 while ((q != NULL) && (q->len <= copy_from)) {
grzemich 0:d7bd7384a37c 1063 copy_from -= q->len;
grzemich 0:d7bd7384a37c 1064 q = q->next;
grzemich 0:d7bd7384a37c 1065 }
grzemich 0:d7bd7384a37c 1066 /* return requested data if pbuf is OK */
grzemich 0:d7bd7384a37c 1067 if ((q != NULL) && (q->len > copy_from)) {
grzemich 0:d7bd7384a37c 1068 return ((u8_t*)q->payload)[copy_from];
grzemich 0:d7bd7384a37c 1069 }
grzemich 0:d7bd7384a37c 1070 return 0;
grzemich 0:d7bd7384a37c 1071 }
grzemich 0:d7bd7384a37c 1072
grzemich 0:d7bd7384a37c 1073 /** Compare pbuf contents at specified offset with memory s2, both of length n
grzemich 0:d7bd7384a37c 1074 *
grzemich 0:d7bd7384a37c 1075 * @param p pbuf to compare
grzemich 0:d7bd7384a37c 1076 * @param offset offset into p at wich to start comparing
grzemich 0:d7bd7384a37c 1077 * @param s2 buffer to compare
grzemich 0:d7bd7384a37c 1078 * @param n length of buffer to compare
grzemich 0:d7bd7384a37c 1079 * @return zero if equal, nonzero otherwise
grzemich 0:d7bd7384a37c 1080 * (0xffff if p is too short, diffoffset+1 otherwise)
grzemich 0:d7bd7384a37c 1081 */
grzemich 0:d7bd7384a37c 1082 u16_t
grzemich 0:d7bd7384a37c 1083 pbuf_memcmp(struct pbuf* p, u16_t offset, const void* s2, u16_t n)
grzemich 0:d7bd7384a37c 1084 {
grzemich 0:d7bd7384a37c 1085 u16_t start = offset;
grzemich 0:d7bd7384a37c 1086 struct pbuf* q = p;
grzemich 0:d7bd7384a37c 1087
grzemich 0:d7bd7384a37c 1088 /* get the correct pbuf */
grzemich 0:d7bd7384a37c 1089 while ((q != NULL) && (q->len <= start)) {
grzemich 0:d7bd7384a37c 1090 start -= q->len;
grzemich 0:d7bd7384a37c 1091 q = q->next;
grzemich 0:d7bd7384a37c 1092 }
grzemich 0:d7bd7384a37c 1093 /* return requested data if pbuf is OK */
grzemich 0:d7bd7384a37c 1094 if ((q != NULL) && (q->len > start)) {
grzemich 0:d7bd7384a37c 1095 u16_t i;
grzemich 0:d7bd7384a37c 1096 for(i = 0; i < n; i++) {
grzemich 0:d7bd7384a37c 1097 u8_t a = pbuf_get_at(q, start + i);
grzemich 0:d7bd7384a37c 1098 u8_t b = ((u8_t*)s2)[i];
grzemich 0:d7bd7384a37c 1099 if (a != b) {
grzemich 0:d7bd7384a37c 1100 return i+1;
grzemich 0:d7bd7384a37c 1101 }
grzemich 0:d7bd7384a37c 1102 }
grzemich 0:d7bd7384a37c 1103 return 0;
grzemich 0:d7bd7384a37c 1104 }
grzemich 0:d7bd7384a37c 1105 return 0xffff;
grzemich 0:d7bd7384a37c 1106 }
grzemich 0:d7bd7384a37c 1107
grzemich 0:d7bd7384a37c 1108 /** Find occurrence of mem (with length mem_len) in pbuf p, starting at offset
grzemich 0:d7bd7384a37c 1109 * start_offset.
grzemich 0:d7bd7384a37c 1110 *
grzemich 0:d7bd7384a37c 1111 * @param p pbuf to search, maximum length is 0xFFFE since 0xFFFF is used as
grzemich 0:d7bd7384a37c 1112 * return value 'not found'
grzemich 0:d7bd7384a37c 1113 * @param mem search for the contents of this buffer
grzemich 0:d7bd7384a37c 1114 * @param mem_len length of 'mem'
grzemich 0:d7bd7384a37c 1115 * @param start_offset offset into p at which to start searching
grzemich 0:d7bd7384a37c 1116 * @return 0xFFFF if substr was not found in p or the index where it was found
grzemich 0:d7bd7384a37c 1117 */
grzemich 0:d7bd7384a37c 1118 u16_t
grzemich 0:d7bd7384a37c 1119 pbuf_memfind(struct pbuf* p, const void* mem, u16_t mem_len, u16_t start_offset)
grzemich 0:d7bd7384a37c 1120 {
grzemich 0:d7bd7384a37c 1121 u16_t i;
grzemich 0:d7bd7384a37c 1122 u16_t max = p->tot_len - mem_len;
grzemich 0:d7bd7384a37c 1123 if (p->tot_len >= mem_len + start_offset) {
grzemich 0:d7bd7384a37c 1124 for(i = start_offset; i <= max; ) {
grzemich 0:d7bd7384a37c 1125 u16_t plus = pbuf_memcmp(p, i, mem, mem_len);
grzemich 0:d7bd7384a37c 1126 if (plus == 0) {
grzemich 0:d7bd7384a37c 1127 return i;
grzemich 0:d7bd7384a37c 1128 } else {
grzemich 0:d7bd7384a37c 1129 i += plus;
grzemich 0:d7bd7384a37c 1130 }
grzemich 0:d7bd7384a37c 1131 }
grzemich 0:d7bd7384a37c 1132 }
grzemich 0:d7bd7384a37c 1133 return 0xFFFF;
grzemich 0:d7bd7384a37c 1134 }
grzemich 0:d7bd7384a37c 1135
grzemich 0:d7bd7384a37c 1136 /** Find occurrence of substr with length substr_len in pbuf p, start at offset
grzemich 0:d7bd7384a37c 1137 * start_offset
grzemich 0:d7bd7384a37c 1138 * WARNING: in contrast to strstr(), this one does not stop at the first \0 in
grzemich 0:d7bd7384a37c 1139 * the pbuf/source string!
grzemich 0:d7bd7384a37c 1140 *
grzemich 0:d7bd7384a37c 1141 * @param p pbuf to search, maximum length is 0xFFFE since 0xFFFF is used as
grzemich 0:d7bd7384a37c 1142 * return value 'not found'
grzemich 0:d7bd7384a37c 1143 * @param substr string to search for in p, maximum length is 0xFFFE
grzemich 0:d7bd7384a37c 1144 * @return 0xFFFF if substr was not found in p or the index where it was found
grzemich 0:d7bd7384a37c 1145 */
grzemich 0:d7bd7384a37c 1146 u16_t
grzemich 0:d7bd7384a37c 1147 pbuf_strstr(struct pbuf* p, const char* substr)
grzemich 0:d7bd7384a37c 1148 {
grzemich 0:d7bd7384a37c 1149 size_t substr_len;
grzemich 0:d7bd7384a37c 1150 if ((substr == NULL) || (substr[0] == 0) || (p->tot_len == 0xFFFF)) {
grzemich 0:d7bd7384a37c 1151 return 0xFFFF;
grzemich 0:d7bd7384a37c 1152 }
grzemich 0:d7bd7384a37c 1153 substr_len = strlen(substr);
grzemich 0:d7bd7384a37c 1154 if (substr_len >= 0xFFFF) {
grzemich 0:d7bd7384a37c 1155 return 0xFFFF;
grzemich 0:d7bd7384a37c 1156 }
grzemich 0:d7bd7384a37c 1157 return pbuf_memfind(p, substr, (u16_t)substr_len, 0);
grzemich 0:d7bd7384a37c 1158 }