Adam Green / Mbed 2 deprecated WeatherStation

Web server based weather station using Sparkfun Weather Meters.

Dependencies:   FatFileSystem mbed WeatherMeters SDFileSystem

NetStack/lwip/core/pbuf.c@1:c7958aa34fa1, 2012-02-25 (annotated)

Committer:
AdamGreen
Date:
Sat Feb 25 03:28:05 2012 +0000
Revision:
1:c7958aa34fa1
Parent:
0:616601bde9fb 
Use published libraries where possible.

Who changed what in which revision?

UserRevisionLine numberNew contents of line
AdamGreen 0:616601bde9fb 1 /**
AdamGreen 0:616601bde9fb 2 * @file
AdamGreen 0:616601bde9fb 3 * Packet buffer management
AdamGreen 0:616601bde9fb 4 *
AdamGreen 0:616601bde9fb 5 * Packets are built from the pbuf data structure. It supports dynamic
AdamGreen 0:616601bde9fb 6 * memory allocation for packet contents or can reference externally
AdamGreen 0:616601bde9fb 7 * managed packet contents both in RAM and ROM. Quick allocation for
AdamGreen 0:616601bde9fb 8 * incoming packets is provided through pools with fixed sized pbufs.
AdamGreen 0:616601bde9fb 9 *
AdamGreen 0:616601bde9fb 10 * A packet may span over multiple pbufs, chained as a singly linked
AdamGreen 0:616601bde9fb 11 * list. This is called a "pbuf chain".
AdamGreen 0:616601bde9fb 12 *
AdamGreen 0:616601bde9fb 13 * Multiple packets may be queued, also using this singly linked list.
AdamGreen 0:616601bde9fb 14 * This is called a "packet queue".
AdamGreen 0:616601bde9fb 15 *
AdamGreen 0:616601bde9fb 16 * So, a packet queue consists of one or more pbuf chains, each of
AdamGreen 0:616601bde9fb 17 * which consist of one or more pbufs. CURRENTLY, PACKET QUEUES ARE
AdamGreen 0:616601bde9fb 18 * NOT SUPPORTED!!! Use helper structs to queue multiple packets.
AdamGreen 0:616601bde9fb 19 *
AdamGreen 0:616601bde9fb 20 * The differences between a pbuf chain and a packet queue are very
AdamGreen 0:616601bde9fb 21 * precise but subtle.
AdamGreen 0:616601bde9fb 22 *
AdamGreen 0:616601bde9fb 23 * The last pbuf of a packet has a ->tot_len field that equals the
AdamGreen 0:616601bde9fb 24 * ->len field. It can be found by traversing the list. If the last
AdamGreen 0:616601bde9fb 25 * pbuf of a packet has a ->next field other than NULL, more packets
AdamGreen 0:616601bde9fb 26 * are on the queue.
AdamGreen 0:616601bde9fb 27 *
AdamGreen 0:616601bde9fb 28 * Therefore, looping through a pbuf of a single packet, has an
AdamGreen 0:616601bde9fb 29 * loop end condition (tot_len == p->len), NOT (next == NULL).
AdamGreen 0:616601bde9fb 30 */
AdamGreen 0:616601bde9fb 31
AdamGreen 0:616601bde9fb 32 /*
AdamGreen 0:616601bde9fb 33 * Copyright (c) 2001-2004 Swedish Institute of Computer Science.
AdamGreen 0:616601bde9fb 34 * All rights reserved.
AdamGreen 0:616601bde9fb 35 *
AdamGreen 0:616601bde9fb 36 * Redistribution and use in source and binary forms, with or without modification,
AdamGreen 0:616601bde9fb 37 * are permitted provided that the following conditions are met:
AdamGreen 0:616601bde9fb 38 *
AdamGreen 0:616601bde9fb 39 * 1. Redistributions of source code must retain the above copyright notice,
AdamGreen 0:616601bde9fb 40 * this list of conditions and the following disclaimer.
AdamGreen 0:616601bde9fb 41 * 2. Redistributions in binary form must reproduce the above copyright notice,
AdamGreen 0:616601bde9fb 42 * this list of conditions and the following disclaimer in the documentation
AdamGreen 0:616601bde9fb 43 * and/or other materials provided with the distribution.
AdamGreen 0:616601bde9fb 44 * 3. The name of the author may not be used to endorse or promote products
AdamGreen 0:616601bde9fb 45 * derived from this software without specific prior written permission.
AdamGreen 0:616601bde9fb 46 *
AdamGreen 0:616601bde9fb 47 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR IMPLIED
AdamGreen 0:616601bde9fb 48 * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
AdamGreen 0:616601bde9fb 49 * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT
AdamGreen 0:616601bde9fb 50 * SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
AdamGreen 0:616601bde9fb 51 * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT
AdamGreen 0:616601bde9fb 52 * OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
AdamGreen 0:616601bde9fb 53 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
AdamGreen 0:616601bde9fb 54 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
AdamGreen 0:616601bde9fb 55 * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY
AdamGreen 0:616601bde9fb 56 * OF SUCH DAMAGE.
AdamGreen 0:616601bde9fb 57 *
AdamGreen 0:616601bde9fb 58 * This file is part of the lwIP TCP/IP stack.
AdamGreen 0:616601bde9fb 59 *
AdamGreen 0:616601bde9fb 60 * Author: Adam Dunkels <adam@sics.se>
AdamGreen 0:616601bde9fb 61 *
AdamGreen 0:616601bde9fb 62 */
AdamGreen 0:616601bde9fb 63
AdamGreen 0:616601bde9fb 64 #include "lwip/opt.h"
AdamGreen 0:616601bde9fb 65
AdamGreen 0:616601bde9fb 66 #include "lwip/stats.h"
AdamGreen 0:616601bde9fb 67 #include "lwip/def.h"
AdamGreen 0:616601bde9fb 68 #include "lwip/mem.h"
AdamGreen 0:616601bde9fb 69 #include "lwip/memp.h"
AdamGreen 0:616601bde9fb 70 #include "lwip/pbuf.h"
AdamGreen 0:616601bde9fb 71 #include "lwip/sys.h"
AdamGreen 0:616601bde9fb 72 #include "arch/perf.h"
AdamGreen 0:616601bde9fb 73 #if TCP_QUEUE_OOSEQ
AdamGreen 0:616601bde9fb 74 #include "lwip/tcp_impl.h"
AdamGreen 0:616601bde9fb 75 #endif
AdamGreen 0:616601bde9fb 76 #if LWIP_CHECKSUM_ON_COPY
AdamGreen 0:616601bde9fb 77 #include "lwip/inet_chksum.h"
AdamGreen 0:616601bde9fb 78 #endif
AdamGreen 0:616601bde9fb 79
AdamGreen 0:616601bde9fb 80 #include <string.h>
AdamGreen 0:616601bde9fb 81
AdamGreen 0:616601bde9fb 82 #define SIZEOF_STRUCT_PBUF LWIP_MEM_ALIGN_SIZE(sizeof(struct pbuf))
AdamGreen 0:616601bde9fb 83 /* Since the pool is created in memp, PBUF_POOL_BUFSIZE will be automatically
AdamGreen 0:616601bde9fb 84 aligned there. Therefore, PBUF_POOL_BUFSIZE_ALIGNED can be used here. */
AdamGreen 0:616601bde9fb 85 #define PBUF_POOL_BUFSIZE_ALIGNED LWIP_MEM_ALIGN_SIZE(PBUF_POOL_BUFSIZE)
AdamGreen 0:616601bde9fb 86
AdamGreen 0:616601bde9fb 87 #if !LWIP_TCP || !TCP_QUEUE_OOSEQ || NO_SYS
AdamGreen 0:616601bde9fb 88 #define PBUF_POOL_IS_EMPTY()
AdamGreen 0:616601bde9fb 89 #else /* !LWIP_TCP || !TCP_QUEUE_OOSEQ || NO_SYS */
AdamGreen 0:616601bde9fb 90 /** Define this to 0 to prevent freeing ooseq pbufs when the PBUF_POOL is empty */
AdamGreen 0:616601bde9fb 91 #ifndef PBUF_POOL_FREE_OOSEQ
AdamGreen 0:616601bde9fb 92 #define PBUF_POOL_FREE_OOSEQ 1
AdamGreen 0:616601bde9fb 93 #endif /* PBUF_POOL_FREE_OOSEQ */
AdamGreen 0:616601bde9fb 94
AdamGreen 0:616601bde9fb 95 #if PBUF_POOL_FREE_OOSEQ
AdamGreen 0:616601bde9fb 96 #include "lwip/tcpip.h"
AdamGreen 0:616601bde9fb 97 #define PBUF_POOL_IS_EMPTY() pbuf_pool_is_empty()
AdamGreen 0:616601bde9fb 98 static u8_t pbuf_free_ooseq_queued;
AdamGreen 0:616601bde9fb 99 /**
AdamGreen 0:616601bde9fb 100 * Attempt to reclaim some memory from queued out-of-sequence TCP segments
AdamGreen 0:616601bde9fb 101 * if we run out of pool pbufs. It's better to give priority to new packets
AdamGreen 0:616601bde9fb 102 * if we're running out.
AdamGreen 0:616601bde9fb 103 *
AdamGreen 0:616601bde9fb 104 * This must be done in the correct thread context therefore this function
AdamGreen 0:616601bde9fb 105 * can only be used with NO_SYS=0 and through tcpip_callback.
AdamGreen 0:616601bde9fb 106 */
AdamGreen 0:616601bde9fb 107 static void
AdamGreen 0:616601bde9fb 108 pbuf_free_ooseq(void* arg)
AdamGreen 0:616601bde9fb 109 {
AdamGreen 0:616601bde9fb 110 struct tcp_pcb* pcb;
AdamGreen 0:616601bde9fb 111 SYS_ARCH_DECL_PROTECT(old_level);
AdamGreen 0:616601bde9fb 112 LWIP_UNUSED_ARG(arg);
AdamGreen 0:616601bde9fb 113
AdamGreen 0:616601bde9fb 114 SYS_ARCH_PROTECT(old_level);
AdamGreen 0:616601bde9fb 115 pbuf_free_ooseq_queued = 0;
AdamGreen 0:616601bde9fb 116 SYS_ARCH_UNPROTECT(old_level);
AdamGreen 0:616601bde9fb 117
AdamGreen 0:616601bde9fb 118 for (pcb = tcp_active_pcbs; NULL != pcb; pcb = pcb->next) {
AdamGreen 0:616601bde9fb 119 if (NULL != pcb->ooseq) {
AdamGreen 0:616601bde9fb 120 /** Free the ooseq pbufs of one PCB only */
AdamGreen 0:616601bde9fb 121 LWIP_DEBUGF(PBUF_DEBUG | LWIP_DBG_TRACE, ("pbuf_free_ooseq: freeing out-of-sequence pbufs\n"));
AdamGreen 0:616601bde9fb 122 tcp_segs_free(pcb->ooseq);
AdamGreen 0:616601bde9fb 123 pcb->ooseq = NULL;
AdamGreen 0:616601bde9fb 124 return;
AdamGreen 0:616601bde9fb 125 }
AdamGreen 0:616601bde9fb 126 }
AdamGreen 0:616601bde9fb 127 }
AdamGreen 0:616601bde9fb 128
AdamGreen 0:616601bde9fb 129 /** Queue a call to pbuf_free_ooseq if not already queued. */
AdamGreen 0:616601bde9fb 130 static void
AdamGreen 0:616601bde9fb 131 pbuf_pool_is_empty(void)
AdamGreen 0:616601bde9fb 132 {
AdamGreen 0:616601bde9fb 133 u8_t queued;
AdamGreen 0:616601bde9fb 134 SYS_ARCH_DECL_PROTECT(old_level);
AdamGreen 0:616601bde9fb 135
AdamGreen 0:616601bde9fb 136 SYS_ARCH_PROTECT(old_level);
AdamGreen 0:616601bde9fb 137 queued = pbuf_free_ooseq_queued;
AdamGreen 0:616601bde9fb 138 pbuf_free_ooseq_queued = 1;
AdamGreen 0:616601bde9fb 139 SYS_ARCH_UNPROTECT(old_level);
AdamGreen 0:616601bde9fb 140
AdamGreen 0:616601bde9fb 141 if(!queued) {
AdamGreen 0:616601bde9fb 142 /* queue a call to pbuf_free_ooseq if not already queued */
AdamGreen 0:616601bde9fb 143 if(tcpip_callback_with_block(pbuf_free_ooseq, NULL, 0) != ERR_OK) {
AdamGreen 0:616601bde9fb 144 SYS_ARCH_PROTECT(old_level);
AdamGreen 0:616601bde9fb 145 pbuf_free_ooseq_queued = 0;
AdamGreen 0:616601bde9fb 146 SYS_ARCH_UNPROTECT(old_level);
AdamGreen 0:616601bde9fb 147 }
AdamGreen 0:616601bde9fb 148 }
AdamGreen 0:616601bde9fb 149 }
AdamGreen 0:616601bde9fb 150 #endif /* PBUF_POOL_FREE_OOSEQ */
AdamGreen 0:616601bde9fb 151 #endif /* !LWIP_TCP || !TCP_QUEUE_OOSEQ || NO_SYS */
AdamGreen 0:616601bde9fb 152
AdamGreen 0:616601bde9fb 153 /**
AdamGreen 0:616601bde9fb 154 * Allocates a pbuf of the given type (possibly a chain for PBUF_POOL type).
AdamGreen 0:616601bde9fb 155 *
AdamGreen 0:616601bde9fb 156 * The actual memory allocated for the pbuf is determined by the
AdamGreen 0:616601bde9fb 157 * layer at which the pbuf is allocated and the requested size
AdamGreen 0:616601bde9fb 158 * (from the size parameter).
AdamGreen 0:616601bde9fb 159 *
AdamGreen 0:616601bde9fb 160 * @param layer flag to define header size
AdamGreen 0:616601bde9fb 161 * @param length size of the pbuf's payload
AdamGreen 0:616601bde9fb 162 * @param type this parameter decides how and where the pbuf
AdamGreen 0:616601bde9fb 163 * should be allocated as follows:
AdamGreen 0:616601bde9fb 164 *
AdamGreen 0:616601bde9fb 165 * - PBUF_RAM: buffer memory for pbuf is allocated as one large
AdamGreen 0:616601bde9fb 166 * chunk. This includes protocol headers as well.
AdamGreen 0:616601bde9fb 167 * - PBUF_ROM: no buffer memory is allocated for the pbuf, even for
AdamGreen 0:616601bde9fb 168 * protocol headers. Additional headers must be prepended
AdamGreen 0:616601bde9fb 169 * by allocating another pbuf and chain in to the front of
AdamGreen 0:616601bde9fb 170 * the ROM pbuf. It is assumed that the memory used is really
AdamGreen 0:616601bde9fb 171 * similar to ROM in that it is immutable and will not be
AdamGreen 0:616601bde9fb 172 * changed. Memory which is dynamic should generally not
AdamGreen 0:616601bde9fb 173 * be attached to PBUF_ROM pbufs. Use PBUF_REF instead.
AdamGreen 0:616601bde9fb 174 * - PBUF_REF: no buffer memory is allocated for the pbuf, even for
AdamGreen 0:616601bde9fb 175 * protocol headers. It is assumed that the pbuf is only
AdamGreen 0:616601bde9fb 176 * being used in a single thread. If the pbuf gets queued,
AdamGreen 0:616601bde9fb 177 * then pbuf_take should be called to copy the buffer.
AdamGreen 0:616601bde9fb 178 * - PBUF_POOL: the pbuf is allocated as a pbuf chain, with pbufs from
AdamGreen 0:616601bde9fb 179 * the pbuf pool that is allocated during pbuf_init().
AdamGreen 0:616601bde9fb 180 *
AdamGreen 0:616601bde9fb 181 * @return the allocated pbuf. If multiple pbufs where allocated, this
AdamGreen 0:616601bde9fb 182 * is the first pbuf of a pbuf chain.
AdamGreen 0:616601bde9fb 183 */
AdamGreen 0:616601bde9fb 184 struct pbuf *
AdamGreen 0:616601bde9fb 185 pbuf_alloc(pbuf_layer layer, u16_t length, pbuf_type type)
AdamGreen 0:616601bde9fb 186 {
AdamGreen 0:616601bde9fb 187 struct pbuf *p, *q, *r;
AdamGreen 0:616601bde9fb 188 u16_t offset;
AdamGreen 0:616601bde9fb 189 s32_t rem_len; /* remaining length */
AdamGreen 0:616601bde9fb 190 LWIP_DEBUGF(PBUF_DEBUG | LWIP_DBG_TRACE, ("pbuf_alloc(length=%"U16_F")\n", length));
AdamGreen 0:616601bde9fb 191
AdamGreen 0:616601bde9fb 192 /* determine header offset */
AdamGreen 0:616601bde9fb 193 offset = 0;
AdamGreen 0:616601bde9fb 194 switch (layer) {
AdamGreen 0:616601bde9fb 195 case PBUF_TRANSPORT:
AdamGreen 0:616601bde9fb 196 /* add room for transport (often TCP) layer header */
AdamGreen 0:616601bde9fb 197 offset += PBUF_TRANSPORT_HLEN;
AdamGreen 0:616601bde9fb 198 /* FALLTHROUGH */
AdamGreen 0:616601bde9fb 199 case PBUF_IP:
AdamGreen 0:616601bde9fb 200 /* add room for IP layer header */
AdamGreen 0:616601bde9fb 201 offset += PBUF_IP_HLEN;
AdamGreen 0:616601bde9fb 202 /* FALLTHROUGH */
AdamGreen 0:616601bde9fb 203 case PBUF_LINK:
AdamGreen 0:616601bde9fb 204 /* add room for link layer header */
AdamGreen 0:616601bde9fb 205 offset += PBUF_LINK_HLEN;
AdamGreen 0:616601bde9fb 206 break;
AdamGreen 0:616601bde9fb 207 case PBUF_RAW:
AdamGreen 0:616601bde9fb 208 break;
AdamGreen 0:616601bde9fb 209 default:
AdamGreen 0:616601bde9fb 210 LWIP_ASSERT("pbuf_alloc: bad pbuf layer", 0);
AdamGreen 0:616601bde9fb 211 return NULL;
AdamGreen 0:616601bde9fb 212 }
AdamGreen 0:616601bde9fb 213
AdamGreen 0:616601bde9fb 214 switch (type) {
AdamGreen 0:616601bde9fb 215 case PBUF_POOL:
AdamGreen 0:616601bde9fb 216 /* allocate head of pbuf chain into p */
AdamGreen 0:616601bde9fb 217 p = (struct pbuf *)memp_malloc(MEMP_PBUF_POOL);
AdamGreen 0:616601bde9fb 218 LWIP_DEBUGF(PBUF_DEBUG | LWIP_DBG_TRACE, ("pbuf_alloc: allocated pbuf %p\n", (void *)p));
AdamGreen 0:616601bde9fb 219 if (p == NULL) {
AdamGreen 0:616601bde9fb 220 PBUF_POOL_IS_EMPTY();
AdamGreen 0:616601bde9fb 221 return NULL;
AdamGreen 0:616601bde9fb 222 }
AdamGreen 0:616601bde9fb 223 p->type = type;
AdamGreen 0:616601bde9fb 224 p->next = NULL;
AdamGreen 0:616601bde9fb 225
AdamGreen 0:616601bde9fb 226 /* make the payload pointer point 'offset' bytes into pbuf data memory */
AdamGreen 0:616601bde9fb 227 p->payload = LWIP_MEM_ALIGN((void *)((u8_t *)p + (SIZEOF_STRUCT_PBUF + offset)));
AdamGreen 0:616601bde9fb 228 LWIP_ASSERT("pbuf_alloc: pbuf p->payload properly aligned",
AdamGreen 0:616601bde9fb 229 ((mem_ptr_t)p->payload % MEM_ALIGNMENT) == 0);
AdamGreen 0:616601bde9fb 230 /* the total length of the pbuf chain is the requested size */
AdamGreen 0:616601bde9fb 231 p->tot_len = length;
AdamGreen 0:616601bde9fb 232 /* set the length of the first pbuf in the chain */
AdamGreen 0:616601bde9fb 233 p->len = LWIP_MIN(length, PBUF_POOL_BUFSIZE_ALIGNED - LWIP_MEM_ALIGN_SIZE(offset));
AdamGreen 0:616601bde9fb 234 LWIP_ASSERT("check p->payload + p->len does not overflow pbuf",
AdamGreen 0:616601bde9fb 235 ((u8_t*)p->payload + p->len <=
AdamGreen 0:616601bde9fb 236 (u8_t*)p + SIZEOF_STRUCT_PBUF + PBUF_POOL_BUFSIZE_ALIGNED));
AdamGreen 0:616601bde9fb 237 LWIP_ASSERT("PBUF_POOL_BUFSIZE must be bigger than MEM_ALIGNMENT",
AdamGreen 0:616601bde9fb 238 (PBUF_POOL_BUFSIZE_ALIGNED - LWIP_MEM_ALIGN_SIZE(offset)) > 0 );
AdamGreen 0:616601bde9fb 239 /* set reference count (needed here in case we fail) */
AdamGreen 0:616601bde9fb 240 p->ref = 1;
AdamGreen 0:616601bde9fb 241
AdamGreen 0:616601bde9fb 242 /* now allocate the tail of the pbuf chain */
AdamGreen 0:616601bde9fb 243
AdamGreen 0:616601bde9fb 244 /* remember first pbuf for linkage in next iteration */
AdamGreen 0:616601bde9fb 245 r = p;
AdamGreen 0:616601bde9fb 246 /* remaining length to be allocated */
AdamGreen 0:616601bde9fb 247 rem_len = length - p->len;
AdamGreen 0:616601bde9fb 248 /* any remaining pbufs to be allocated? */
AdamGreen 0:616601bde9fb 249 while (rem_len > 0) {
AdamGreen 0:616601bde9fb 250 q = (struct pbuf *)memp_malloc(MEMP_PBUF_POOL);
AdamGreen 0:616601bde9fb 251 if (q == NULL) {
AdamGreen 0:616601bde9fb 252 PBUF_POOL_IS_EMPTY();
AdamGreen 0:616601bde9fb 253 /* free chain so far allocated */
AdamGreen 0:616601bde9fb 254 pbuf_free(p);
AdamGreen 0:616601bde9fb 255 /* bail out unsuccesfully */
AdamGreen 0:616601bde9fb 256 return NULL;
AdamGreen 0:616601bde9fb 257 }
AdamGreen 0:616601bde9fb 258 q->type = type;
AdamGreen 0:616601bde9fb 259 q->flags = 0;
AdamGreen 0:616601bde9fb 260 q->next = NULL;
AdamGreen 0:616601bde9fb 261 /* make previous pbuf point to this pbuf */
AdamGreen 0:616601bde9fb 262 r->next = q;
AdamGreen 0:616601bde9fb 263 /* set total length of this pbuf and next in chain */
AdamGreen 0:616601bde9fb 264 LWIP_ASSERT("rem_len < max_u16_t", rem_len < 0xffff);
AdamGreen 0:616601bde9fb 265 q->tot_len = (u16_t)rem_len;
AdamGreen 0:616601bde9fb 266 /* this pbuf length is pool size, unless smaller sized tail */
AdamGreen 0:616601bde9fb 267 q->len = LWIP_MIN((u16_t)rem_len, PBUF_POOL_BUFSIZE_ALIGNED);
AdamGreen 0:616601bde9fb 268 q->payload = (void *)((u8_t *)q + SIZEOF_STRUCT_PBUF);
AdamGreen 0:616601bde9fb 269 LWIP_ASSERT("pbuf_alloc: pbuf q->payload properly aligned",
AdamGreen 0:616601bde9fb 270 ((mem_ptr_t)q->payload % MEM_ALIGNMENT) == 0);
AdamGreen 0:616601bde9fb 271 LWIP_ASSERT("check p->payload + p->len does not overflow pbuf",
AdamGreen 0:616601bde9fb 272 ((u8_t*)p->payload + p->len <=
AdamGreen 0:616601bde9fb 273 (u8_t*)p + SIZEOF_STRUCT_PBUF + PBUF_POOL_BUFSIZE_ALIGNED));
AdamGreen 0:616601bde9fb 274 q->ref = 1;
AdamGreen 0:616601bde9fb 275 /* calculate remaining length to be allocated */
AdamGreen 0:616601bde9fb 276 rem_len -= q->len;
AdamGreen 0:616601bde9fb 277 /* remember this pbuf for linkage in next iteration */
AdamGreen 0:616601bde9fb 278 r = q;
AdamGreen 0:616601bde9fb 279 }
AdamGreen 0:616601bde9fb 280 /* end of chain */
AdamGreen 0:616601bde9fb 281 /*r->next = NULL;*/
AdamGreen 0:616601bde9fb 282
AdamGreen 0:616601bde9fb 283 break;
AdamGreen 0:616601bde9fb 284 case PBUF_RAM:
AdamGreen 0:616601bde9fb 285 /* If pbuf is to be allocated in RAM, allocate memory for it. */
AdamGreen 0:616601bde9fb 286 p = (struct pbuf*)mem_malloc(LWIP_MEM_ALIGN_SIZE(SIZEOF_STRUCT_PBUF + offset) + LWIP_MEM_ALIGN_SIZE(length));
AdamGreen 0:616601bde9fb 287 if (p == NULL) {
AdamGreen 0:616601bde9fb 288 return NULL;
AdamGreen 0:616601bde9fb 289 }
AdamGreen 0:616601bde9fb 290 /* Set up internal structure of the pbuf. */
AdamGreen 0:616601bde9fb 291 p->payload = LWIP_MEM_ALIGN((void *)((u8_t *)p + SIZEOF_STRUCT_PBUF + offset));
AdamGreen 0:616601bde9fb 292 p->len = p->tot_len = length;
AdamGreen 0:616601bde9fb 293 p->next = NULL;
AdamGreen 0:616601bde9fb 294 p->type = type;
AdamGreen 0:616601bde9fb 295
AdamGreen 0:616601bde9fb 296 LWIP_ASSERT("pbuf_alloc: pbuf->payload properly aligned",
AdamGreen 0:616601bde9fb 297 ((mem_ptr_t)p->payload % MEM_ALIGNMENT) == 0);
AdamGreen 0:616601bde9fb 298 break;
AdamGreen 0:616601bde9fb 299 /* pbuf references existing (non-volatile static constant) ROM payload? */
AdamGreen 0:616601bde9fb 300 case PBUF_ROM:
AdamGreen 0:616601bde9fb 301 /* pbuf references existing (externally allocated) RAM payload? */
AdamGreen 0:616601bde9fb 302 case PBUF_REF:
AdamGreen 0:616601bde9fb 303 /* only allocate memory for the pbuf structure */
AdamGreen 0:616601bde9fb 304 p = (struct pbuf *)memp_malloc(MEMP_PBUF);
AdamGreen 0:616601bde9fb 305 if (p == NULL) {
AdamGreen 0:616601bde9fb 306 LWIP_DEBUGF(PBUF_DEBUG | LWIP_DBG_LEVEL_SERIOUS,
AdamGreen 0:616601bde9fb 307 ("pbuf_alloc: Could not allocate MEMP_PBUF for PBUF_%s.\n",
AdamGreen 0:616601bde9fb 308 (type == PBUF_ROM) ? "ROM" : "REF"));
AdamGreen 0:616601bde9fb 309 return NULL;
AdamGreen 0:616601bde9fb 310 }
AdamGreen 0:616601bde9fb 311 /* caller must set this field properly, afterwards */
AdamGreen 0:616601bde9fb 312 p->payload = NULL;
AdamGreen 0:616601bde9fb 313 p->len = p->tot_len = length;
AdamGreen 0:616601bde9fb 314 p->next = NULL;
AdamGreen 0:616601bde9fb 315 p->type = type;
AdamGreen 0:616601bde9fb 316 break;
AdamGreen 0:616601bde9fb 317 default:
AdamGreen 0:616601bde9fb 318 LWIP_ASSERT("pbuf_alloc: erroneous type", 0);
AdamGreen 0:616601bde9fb 319 return NULL;
AdamGreen 0:616601bde9fb 320 }
AdamGreen 0:616601bde9fb 321 /* set reference count */
AdamGreen 0:616601bde9fb 322 p->ref = 1;
AdamGreen 0:616601bde9fb 323 /* set flags */
AdamGreen 0:616601bde9fb 324 p->flags = 0;
AdamGreen 0:616601bde9fb 325 LWIP_DEBUGF(PBUF_DEBUG | LWIP_DBG_TRACE, ("pbuf_alloc(length=%"U16_F") == %p\n", length, (void *)p));
AdamGreen 0:616601bde9fb 326 return p;
AdamGreen 0:616601bde9fb 327 }
AdamGreen 0:616601bde9fb 328
AdamGreen 0:616601bde9fb 329 #if LWIP_SUPPORT_CUSTOM_PBUF
AdamGreen 0:616601bde9fb 330 /** Initialize a custom pbuf (already allocated).
AdamGreen 0:616601bde9fb 331 *
AdamGreen 0:616601bde9fb 332 * @param layer flag to define header size
AdamGreen 0:616601bde9fb 333 * @param length size of the pbuf's payload
AdamGreen 0:616601bde9fb 334 * @param type type of the pbuf (only used to treat the pbuf accordingly, as
AdamGreen 0:616601bde9fb 335 * this function allocates no memory)
AdamGreen 0:616601bde9fb 336 * @param p pointer to the custom pbuf to initialize (already allocated)
AdamGreen 0:616601bde9fb 337 * @param payload_mem pointer to the buffer that is used for payload and headers,
AdamGreen 0:616601bde9fb 338 * must be at least big enough to hold 'length' plus the header size,
AdamGreen 0:616601bde9fb 339 * may be NULL if set later
AdamGreen 0:616601bde9fb 340 * @param payload_mem_len the size of the 'payload_mem' buffer, must be at least
AdamGreen 0:616601bde9fb 341 * big enough to hold 'length' plus the header size
AdamGreen 0:616601bde9fb 342 */
AdamGreen 0:616601bde9fb 343 struct pbuf*
AdamGreen 0:616601bde9fb 344 pbuf_alloced_custom(pbuf_layer l, u16_t length, pbuf_type type, struct pbuf_custom *p,
AdamGreen 0:616601bde9fb 345 void *payload_mem, u16_t payload_mem_len)
AdamGreen 0:616601bde9fb 346 {
AdamGreen 0:616601bde9fb 347 u16_t offset;
AdamGreen 0:616601bde9fb 348 LWIP_DEBUGF(PBUF_DEBUG | LWIP_DBG_TRACE, ("pbuf_alloced_custom(length=%"U16_F")\n", length));
AdamGreen 0:616601bde9fb 349
AdamGreen 0:616601bde9fb 350 /* determine header offset */
AdamGreen 0:616601bde9fb 351 offset = 0;
AdamGreen 0:616601bde9fb 352 switch (l) {
AdamGreen 0:616601bde9fb 353 case PBUF_TRANSPORT:
AdamGreen 0:616601bde9fb 354 /* add room for transport (often TCP) layer header */
AdamGreen 0:616601bde9fb 355 offset += PBUF_TRANSPORT_HLEN;
AdamGreen 0:616601bde9fb 356 /* FALLTHROUGH */
AdamGreen 0:616601bde9fb 357 case PBUF_IP:
AdamGreen 0:616601bde9fb 358 /* add room for IP layer header */
AdamGreen 0:616601bde9fb 359 offset += PBUF_IP_HLEN;
AdamGreen 0:616601bde9fb 360 /* FALLTHROUGH */
AdamGreen 0:616601bde9fb 361 case PBUF_LINK:
AdamGreen 0:616601bde9fb 362 /* add room for link layer header */
AdamGreen 0:616601bde9fb 363 offset += PBUF_LINK_HLEN;
AdamGreen 0:616601bde9fb 364 break;
AdamGreen 0:616601bde9fb 365 case PBUF_RAW:
AdamGreen 0:616601bde9fb 366 break;
AdamGreen 0:616601bde9fb 367 default:
AdamGreen 0:616601bde9fb 368 LWIP_ASSERT("pbuf_alloced_custom: bad pbuf layer", 0);
AdamGreen 0:616601bde9fb 369 return NULL;
AdamGreen 0:616601bde9fb 370 }
AdamGreen 0:616601bde9fb 371
AdamGreen 0:616601bde9fb 372 if (LWIP_MEM_ALIGN_SIZE(offset) + length < payload_mem_len) {
AdamGreen 0:616601bde9fb 373 LWIP_DEBUGF(PBUF_DEBUG | LWIP_DBG_LEVEL_WARNING, ("pbuf_alloced_custom(length=%"U16_F") buffer too short\n", length));
AdamGreen 0:616601bde9fb 374 return NULL;
AdamGreen 0:616601bde9fb 375 }
AdamGreen 0:616601bde9fb 376
AdamGreen 0:616601bde9fb 377 p->pbuf.next = NULL;
AdamGreen 0:616601bde9fb 378 if (payload_mem != NULL) {
AdamGreen 0:616601bde9fb 379 p->pbuf.payload = LWIP_MEM_ALIGN((void *)((u8_t *)payload_mem + offset));
AdamGreen 0:616601bde9fb 380 } else {
AdamGreen 0:616601bde9fb 381 p->pbuf.payload = NULL;
AdamGreen 0:616601bde9fb 382 }
AdamGreen 0:616601bde9fb 383 p->pbuf.flags = PBUF_FLAG_IS_CUSTOM;
AdamGreen 0:616601bde9fb 384 p->pbuf.len = p->pbuf.tot_len = length;
AdamGreen 0:616601bde9fb 385 p->pbuf.type = type;
AdamGreen 0:616601bde9fb 386 p->pbuf.ref = 1;
AdamGreen 0:616601bde9fb 387 return &p->pbuf;
AdamGreen 0:616601bde9fb 388 }
AdamGreen 0:616601bde9fb 389 #endif /* LWIP_SUPPORT_CUSTOM_PBUF */
AdamGreen 0:616601bde9fb 390
AdamGreen 0:616601bde9fb 391 /**
AdamGreen 0:616601bde9fb 392 * Shrink a pbuf chain to a desired length.
AdamGreen 0:616601bde9fb 393 *
AdamGreen 0:616601bde9fb 394 * @param p pbuf to shrink.
AdamGreen 0:616601bde9fb 395 * @param new_len desired new length of pbuf chain
AdamGreen 0:616601bde9fb 396 *
AdamGreen 0:616601bde9fb 397 * Depending on the desired length, the first few pbufs in a chain might
AdamGreen 0:616601bde9fb 398 * be skipped and left unchanged. The new last pbuf in the chain will be
AdamGreen 0:616601bde9fb 399 * resized, and any remaining pbufs will be freed.
AdamGreen 0:616601bde9fb 400 *
AdamGreen 0:616601bde9fb 401 * @note If the pbuf is ROM/REF, only the ->tot_len and ->len fields are adjusted.
AdamGreen 0:616601bde9fb 402 * @note May not be called on a packet queue.
AdamGreen 0:616601bde9fb 403 *
AdamGreen 0:616601bde9fb 404 * @note Despite its name, pbuf_realloc cannot grow the size of a pbuf (chain).
AdamGreen 0:616601bde9fb 405 */
AdamGreen 0:616601bde9fb 406 void
AdamGreen 0:616601bde9fb 407 pbuf_realloc(struct pbuf *p, u16_t new_len)
AdamGreen 0:616601bde9fb 408 {
AdamGreen 0:616601bde9fb 409 struct pbuf *q;
AdamGreen 0:616601bde9fb 410 u16_t rem_len; /* remaining length */
AdamGreen 0:616601bde9fb 411 s32_t grow;
AdamGreen 0:616601bde9fb 412
AdamGreen 0:616601bde9fb 413 LWIP_ASSERT("pbuf_realloc: p != NULL", p != NULL);
AdamGreen 0:616601bde9fb 414 LWIP_ASSERT("pbuf_realloc: sane p->type", p->type == PBUF_POOL ||
AdamGreen 0:616601bde9fb 415 p->type == PBUF_ROM ||
AdamGreen 0:616601bde9fb 416 p->type == PBUF_RAM ||
AdamGreen 0:616601bde9fb 417 p->type == PBUF_REF);
AdamGreen 0:616601bde9fb 418
AdamGreen 0:616601bde9fb 419 /* desired length larger than current length? */
AdamGreen 0:616601bde9fb 420 if (new_len >= p->tot_len) {
AdamGreen 0:616601bde9fb 421 /* enlarging not yet supported */
AdamGreen 0:616601bde9fb 422 return;
AdamGreen 0:616601bde9fb 423 }
AdamGreen 0:616601bde9fb 424
AdamGreen 0:616601bde9fb 425 /* the pbuf chain grows by (new_len - p->tot_len) bytes
AdamGreen 0:616601bde9fb 426 * (which may be negative in case of shrinking) */
AdamGreen 0:616601bde9fb 427 grow = new_len - p->tot_len;
AdamGreen 0:616601bde9fb 428
AdamGreen 0:616601bde9fb 429 /* first, step over any pbufs that should remain in the chain */
AdamGreen 0:616601bde9fb 430 rem_len = new_len;
AdamGreen 0:616601bde9fb 431 q = p;
AdamGreen 0:616601bde9fb 432 /* should this pbuf be kept? */
AdamGreen 0:616601bde9fb 433 while (rem_len > q->len) {
AdamGreen 0:616601bde9fb 434 /* decrease remaining length by pbuf length */
AdamGreen 0:616601bde9fb 435 rem_len -= q->len;
AdamGreen 0:616601bde9fb 436 /* decrease total length indicator */
AdamGreen 0:616601bde9fb 437 LWIP_ASSERT("grow < max_u16_t", grow < 0xffff);
AdamGreen 0:616601bde9fb 438 q->tot_len += (u16_t)grow;
AdamGreen 0:616601bde9fb 439 /* proceed to next pbuf in chain */
AdamGreen 0:616601bde9fb 440 q = q->next;
AdamGreen 0:616601bde9fb 441 LWIP_ASSERT("pbuf_realloc: q != NULL", q != NULL);
AdamGreen 0:616601bde9fb 442 }
AdamGreen 0:616601bde9fb 443 /* we have now reached the new last pbuf (in q) */
AdamGreen 0:616601bde9fb 444 /* rem_len == desired length for pbuf q */
AdamGreen 0:616601bde9fb 445
AdamGreen 0:616601bde9fb 446 /* shrink allocated memory for PBUF_RAM */
AdamGreen 0:616601bde9fb 447 /* (other types merely adjust their length fields */
AdamGreen 0:616601bde9fb 448 if ((q->type == PBUF_RAM) && (rem_len != q->len)) {
AdamGreen 0:616601bde9fb 449 /* reallocate and adjust the length of the pbuf that will be split */
AdamGreen 0:616601bde9fb 450 q = (struct pbuf *)mem_trim(q, (u16_t)((u8_t *)q->payload - (u8_t *)q) + rem_len);
AdamGreen 0:616601bde9fb 451 LWIP_ASSERT("mem_trim returned q == NULL", q != NULL);
AdamGreen 0:616601bde9fb 452 }
AdamGreen 0:616601bde9fb 453 /* adjust length fields for new last pbuf */
AdamGreen 0:616601bde9fb 454 q->len = rem_len;
AdamGreen 0:616601bde9fb 455 q->tot_len = q->len;
AdamGreen 0:616601bde9fb 456
AdamGreen 0:616601bde9fb 457 /* any remaining pbufs in chain? */
AdamGreen 0:616601bde9fb 458 if (q->next != NULL) {
AdamGreen 0:616601bde9fb 459 /* free remaining pbufs in chain */
AdamGreen 0:616601bde9fb 460 pbuf_free(q->next);
AdamGreen 0:616601bde9fb 461 }
AdamGreen 0:616601bde9fb 462 /* q is last packet in chain */
AdamGreen 0:616601bde9fb 463 q->next = NULL;
AdamGreen 0:616601bde9fb 464
AdamGreen 0:616601bde9fb 465 }
AdamGreen 0:616601bde9fb 466
AdamGreen 0:616601bde9fb 467 /**
AdamGreen 0:616601bde9fb 468 * Adjusts the payload pointer to hide or reveal headers in the payload.
AdamGreen 0:616601bde9fb 469 *
AdamGreen 0:616601bde9fb 470 * Adjusts the ->payload pointer so that space for a header
AdamGreen 0:616601bde9fb 471 * (dis)appears in the pbuf payload.
AdamGreen 0:616601bde9fb 472 *
AdamGreen 0:616601bde9fb 473 * The ->payload, ->tot_len and ->len fields are adjusted.
AdamGreen 0:616601bde9fb 474 *
AdamGreen 0:616601bde9fb 475 * @param p pbuf to change the header size.
AdamGreen 0:616601bde9fb 476 * @param header_size_increment Number of bytes to increment header size which
AdamGreen 0:616601bde9fb 477 * increases the size of the pbuf. New space is on the front.
AdamGreen 0:616601bde9fb 478 * (Using a negative value decreases the header size.)
AdamGreen 0:616601bde9fb 479 * If hdr_size_inc is 0, this function does nothing and returns succesful.
AdamGreen 0:616601bde9fb 480 *
AdamGreen 0:616601bde9fb 481 * PBUF_ROM and PBUF_REF type buffers cannot have their sizes increased, so
AdamGreen 0:616601bde9fb 482 * the call will fail. A check is made that the increase in header size does
AdamGreen 0:616601bde9fb 483 * not move the payload pointer in front of the start of the buffer.
AdamGreen 0:616601bde9fb 484 * @return non-zero on failure, zero on success.
AdamGreen 0:616601bde9fb 485 *
AdamGreen 0:616601bde9fb 486 */
AdamGreen 0:616601bde9fb 487 u8_t
AdamGreen 0:616601bde9fb 488 pbuf_header(struct pbuf *p, s16_t header_size_increment)
AdamGreen 0:616601bde9fb 489 {
AdamGreen 0:616601bde9fb 490 u16_t type;
AdamGreen 0:616601bde9fb 491 void *payload;
AdamGreen 0:616601bde9fb 492 u16_t increment_magnitude;
AdamGreen 0:616601bde9fb 493
AdamGreen 0:616601bde9fb 494 LWIP_ASSERT("p != NULL", p != NULL);
AdamGreen 0:616601bde9fb 495 if ((header_size_increment == 0) || (p == NULL)) {
AdamGreen 0:616601bde9fb 496 return 0;
AdamGreen 0:616601bde9fb 497 }
AdamGreen 0:616601bde9fb 498
AdamGreen 0:616601bde9fb 499 if (header_size_increment < 0){
AdamGreen 0:616601bde9fb 500 increment_magnitude = -header_size_increment;
AdamGreen 0:616601bde9fb 501 /* Check that we aren't going to move off the end of the pbuf */
AdamGreen 0:616601bde9fb 502 LWIP_ERROR("increment_magnitude <= p->len", (increment_magnitude <= p->len), return 1;);
AdamGreen 0:616601bde9fb 503 } else {
AdamGreen 0:616601bde9fb 504 increment_magnitude = header_size_increment;
AdamGreen 0:616601bde9fb 505 #if 0
AdamGreen 0:616601bde9fb 506 /* Can't assert these as some callers speculatively call
AdamGreen 0:616601bde9fb 507 pbuf_header() to see if it's OK. Will return 1 below instead. */
AdamGreen 0:616601bde9fb 508 /* Check that we've got the correct type of pbuf to work with */
AdamGreen 0:616601bde9fb 509 LWIP_ASSERT("p->type == PBUF_RAM || p->type == PBUF_POOL",
AdamGreen 0:616601bde9fb 510 p->type == PBUF_RAM || p->type == PBUF_POOL);
AdamGreen 0:616601bde9fb 511 /* Check that we aren't going to move off the beginning of the pbuf */
AdamGreen 0:616601bde9fb 512 LWIP_ASSERT("p->payload - increment_magnitude >= p + SIZEOF_STRUCT_PBUF",
AdamGreen 0:616601bde9fb 513 (u8_t *)p->payload - increment_magnitude >= (u8_t *)p + SIZEOF_STRUCT_PBUF);
AdamGreen 0:616601bde9fb 514 #endif
AdamGreen 0:616601bde9fb 515 }
AdamGreen 0:616601bde9fb 516
AdamGreen 0:616601bde9fb 517 type = p->type;
AdamGreen 0:616601bde9fb 518 /* remember current payload pointer */
AdamGreen 0:616601bde9fb 519 payload = p->payload;
AdamGreen 0:616601bde9fb 520
AdamGreen 0:616601bde9fb 521 /* pbuf types containing payloads? */
AdamGreen 0:616601bde9fb 522 if (type == PBUF_RAM || type == PBUF_POOL) {
AdamGreen 0:616601bde9fb 523 /* set new payload pointer */
AdamGreen 0:616601bde9fb 524 p->payload = (u8_t *)p->payload - header_size_increment;
AdamGreen 0:616601bde9fb 525 /* boundary check fails? */
AdamGreen 0:616601bde9fb 526 if ((u8_t *)p->payload < (u8_t *)p + SIZEOF_STRUCT_PBUF) {
AdamGreen 0:616601bde9fb 527 LWIP_DEBUGF( PBUF_DEBUG | LWIP_DBG_LEVEL_SERIOUS,
AdamGreen 0:616601bde9fb 528 ("pbuf_header: failed as %p < %p (not enough space for new header size)\n",
AdamGreen 0:616601bde9fb 529 (void *)p->payload, (void *)(p + 1)));
AdamGreen 0:616601bde9fb 530 /* restore old payload pointer */
AdamGreen 0:616601bde9fb 531 p->payload = payload;
AdamGreen 0:616601bde9fb 532 /* bail out unsuccesfully */
AdamGreen 0:616601bde9fb 533 return 1;
AdamGreen 0:616601bde9fb 534 }
AdamGreen 0:616601bde9fb 535 /* pbuf types refering to external payloads? */
AdamGreen 0:616601bde9fb 536 } else if (type == PBUF_REF || type == PBUF_ROM) {
AdamGreen 0:616601bde9fb 537 /* hide a header in the payload? */
AdamGreen 0:616601bde9fb 538 if ((header_size_increment < 0) && (increment_magnitude <= p->len)) {
AdamGreen 0:616601bde9fb 539 /* increase payload pointer */
AdamGreen 0:616601bde9fb 540 p->payload = (u8_t *)p->payload - header_size_increment;
AdamGreen 0:616601bde9fb 541 } else {
AdamGreen 0:616601bde9fb 542 /* cannot expand payload to front (yet!)
AdamGreen 0:616601bde9fb 543 * bail out unsuccesfully */
AdamGreen 0:616601bde9fb 544 return 1;
AdamGreen 0:616601bde9fb 545 }
AdamGreen 0:616601bde9fb 546 } else {
AdamGreen 0:616601bde9fb 547 /* Unknown type */
AdamGreen 0:616601bde9fb 548 LWIP_ASSERT("bad pbuf type", 0);
AdamGreen 0:616601bde9fb 549 return 1;
AdamGreen 0:616601bde9fb 550 }
AdamGreen 0:616601bde9fb 551 /* modify pbuf length fields */
AdamGreen 0:616601bde9fb 552 p->len += header_size_increment;
AdamGreen 0:616601bde9fb 553 p->tot_len += header_size_increment;
AdamGreen 0:616601bde9fb 554
AdamGreen 0:616601bde9fb 555 LWIP_DEBUGF(PBUF_DEBUG | LWIP_DBG_TRACE, ("pbuf_header: old %p new %p (%"S16_F")\n",
AdamGreen 0:616601bde9fb 556 (void *)payload, (void *)p->payload, header_size_increment));
AdamGreen 0:616601bde9fb 557
AdamGreen 0:616601bde9fb 558 return 0;
AdamGreen 0:616601bde9fb 559 }
AdamGreen 0:616601bde9fb 560
AdamGreen 0:616601bde9fb 561 /**
AdamGreen 0:616601bde9fb 562 * Dereference a pbuf chain or queue and deallocate any no-longer-used
AdamGreen 0:616601bde9fb 563 * pbufs at the head of this chain or queue.
AdamGreen 0:616601bde9fb 564 *
AdamGreen 0:616601bde9fb 565 * Decrements the pbuf reference count. If it reaches zero, the pbuf is
AdamGreen 0:616601bde9fb 566 * deallocated.
AdamGreen 0:616601bde9fb 567 *
AdamGreen 0:616601bde9fb 568 * For a pbuf chain, this is repeated for each pbuf in the chain,
AdamGreen 0:616601bde9fb 569 * up to the first pbuf which has a non-zero reference count after
AdamGreen 0:616601bde9fb 570 * decrementing. So, when all reference counts are one, the whole
AdamGreen 0:616601bde9fb 571 * chain is free'd.
AdamGreen 0:616601bde9fb 572 *
AdamGreen 0:616601bde9fb 573 * @param p The pbuf (chain) to be dereferenced.
AdamGreen 0:616601bde9fb 574 *
AdamGreen 0:616601bde9fb 575 * @return the number of pbufs that were de-allocated
AdamGreen 0:616601bde9fb 576 * from the head of the chain.
AdamGreen 0:616601bde9fb 577 *
AdamGreen 0:616601bde9fb 578 * @note MUST NOT be called on a packet queue (Not verified to work yet).
AdamGreen 0:616601bde9fb 579 * @note the reference counter of a pbuf equals the number of pointers
AdamGreen 0:616601bde9fb 580 * that refer to the pbuf (or into the pbuf).
AdamGreen 0:616601bde9fb 581 *
AdamGreen 0:616601bde9fb 582 * @internal examples:
AdamGreen 0:616601bde9fb 583 *
AdamGreen 0:616601bde9fb 584 * Assuming existing chains a->b->c with the following reference
AdamGreen 0:616601bde9fb 585 * counts, calling pbuf_free(a) results in:
AdamGreen 0:616601bde9fb 586 *
AdamGreen 0:616601bde9fb 587 * 1->2->3 becomes ...1->3
AdamGreen 0:616601bde9fb 588 * 3->3->3 becomes 2->3->3
AdamGreen 0:616601bde9fb 589 * 1->1->2 becomes ......1
AdamGreen 0:616601bde9fb 590 * 2->1->1 becomes 1->1->1
AdamGreen 0:616601bde9fb 591 * 1->1->1 becomes .......
AdamGreen 0:616601bde9fb 592 *
AdamGreen 0:616601bde9fb 593 */
AdamGreen 0:616601bde9fb 594 u8_t
AdamGreen 0:616601bde9fb 595 pbuf_free(struct pbuf *p)
AdamGreen 0:616601bde9fb 596 {
AdamGreen 0:616601bde9fb 597 u16_t type;
AdamGreen 0:616601bde9fb 598 struct pbuf *q;
AdamGreen 0:616601bde9fb 599 u8_t count;
AdamGreen 0:616601bde9fb 600
AdamGreen 0:616601bde9fb 601 if (p == NULL) {
AdamGreen 0:616601bde9fb 602 LWIP_ASSERT("p != NULL", p != NULL);
AdamGreen 0:616601bde9fb 603 /* if assertions are disabled, proceed with debug output */
AdamGreen 0:616601bde9fb 604 LWIP_DEBUGF(PBUF_DEBUG | LWIP_DBG_LEVEL_SERIOUS,
AdamGreen 0:616601bde9fb 605 ("pbuf_free(p == NULL) was called.\n"));
AdamGreen 0:616601bde9fb 606 return 0;
AdamGreen 0:616601bde9fb 607 }
AdamGreen 0:616601bde9fb 608 LWIP_DEBUGF(PBUF_DEBUG | LWIP_DBG_TRACE, ("pbuf_free(%p)\n", (void *)p));
AdamGreen 0:616601bde9fb 609
AdamGreen 0:616601bde9fb 610 PERF_START;
AdamGreen 0:616601bde9fb 611
AdamGreen 0:616601bde9fb 612 LWIP_ASSERT("pbuf_free: sane type",
AdamGreen 0:616601bde9fb 613 p->type == PBUF_RAM || p->type == PBUF_ROM ||
AdamGreen 0:616601bde9fb 614 p->type == PBUF_REF || p->type == PBUF_POOL);
AdamGreen 0:616601bde9fb 615
AdamGreen 0:616601bde9fb 616 count = 0;
AdamGreen 0:616601bde9fb 617 /* de-allocate all consecutive pbufs from the head of the chain that
AdamGreen 0:616601bde9fb 618 * obtain a zero reference count after decrementing*/
AdamGreen 0:616601bde9fb 619 while (p != NULL) {
AdamGreen 0:616601bde9fb 620 u16_t ref;
AdamGreen 0:616601bde9fb 621 SYS_ARCH_DECL_PROTECT(old_level);
AdamGreen 0:616601bde9fb 622 /* Since decrementing ref cannot be guaranteed to be a single machine operation
AdamGreen 0:616601bde9fb 623 * we must protect it. We put the new ref into a local variable to prevent
AdamGreen 0:616601bde9fb 624 * further protection. */
AdamGreen 0:616601bde9fb 625 SYS_ARCH_PROTECT(old_level);
AdamGreen 0:616601bde9fb 626 /* all pbufs in a chain are referenced at least once */
AdamGreen 0:616601bde9fb 627 LWIP_ASSERT("pbuf_free: p->ref > 0", p->ref > 0);
AdamGreen 0:616601bde9fb 628 /* decrease reference count (number of pointers to pbuf) */
AdamGreen 0:616601bde9fb 629 ref = --(p->ref);
AdamGreen 0:616601bde9fb 630 SYS_ARCH_UNPROTECT(old_level);
AdamGreen 0:616601bde9fb 631 /* this pbuf is no longer referenced to? */
AdamGreen 0:616601bde9fb 632 if (ref == 0) {
AdamGreen 0:616601bde9fb 633 /* remember next pbuf in chain for next iteration */
AdamGreen 0:616601bde9fb 634 q = p->next;
AdamGreen 0:616601bde9fb 635 LWIP_DEBUGF( PBUF_DEBUG | LWIP_DBG_TRACE, ("pbuf_free: deallocating %p\n", (void *)p));
AdamGreen 0:616601bde9fb 636 type = p->type;
AdamGreen 0:616601bde9fb 637 #if LWIP_SUPPORT_CUSTOM_PBUF
AdamGreen 0:616601bde9fb 638 /* is this a custom pbuf? */
AdamGreen 0:616601bde9fb 639 if ((p->flags & PBUF_FLAG_IS_CUSTOM) != 0) {
AdamGreen 0:616601bde9fb 640 struct pbuf_custom *pc = (struct pbuf_custom*)p;
AdamGreen 0:616601bde9fb 641 LWIP_ASSERT("pc->custom_free_function != NULL", pc->custom_free_function != NULL);
AdamGreen 0:616601bde9fb 642 pc->custom_free_function(p);
AdamGreen 0:616601bde9fb 643 } else
AdamGreen 0:616601bde9fb 644 #endif /* LWIP_SUPPORT_CUSTOM_PBUF */
AdamGreen 0:616601bde9fb 645 {
AdamGreen 0:616601bde9fb 646 /* is this a pbuf from the pool? */
AdamGreen 0:616601bde9fb 647 if (type == PBUF_POOL) {
AdamGreen 0:616601bde9fb 648 memp_free(MEMP_PBUF_POOL, p);
AdamGreen 0:616601bde9fb 649 /* is this a ROM or RAM referencing pbuf? */
AdamGreen 0:616601bde9fb 650 } else if (type == PBUF_ROM || type == PBUF_REF) {
AdamGreen 0:616601bde9fb 651 memp_free(MEMP_PBUF, p);
AdamGreen 0:616601bde9fb 652 /* type == PBUF_RAM */
AdamGreen 0:616601bde9fb 653 } else {
AdamGreen 0:616601bde9fb 654 mem_free(p);
AdamGreen 0:616601bde9fb 655 }
AdamGreen 0:616601bde9fb 656 }
AdamGreen 0:616601bde9fb 657 count++;
AdamGreen 0:616601bde9fb 658 /* proceed to next pbuf */
AdamGreen 0:616601bde9fb 659 p = q;
AdamGreen 0:616601bde9fb 660 /* p->ref > 0, this pbuf is still referenced to */
AdamGreen 0:616601bde9fb 661 /* (and so the remaining pbufs in chain as well) */
AdamGreen 0:616601bde9fb 662 } else {
AdamGreen 0:616601bde9fb 663 LWIP_DEBUGF( PBUF_DEBUG | LWIP_DBG_TRACE, ("pbuf_free: %p has ref %"U16_F", ending here.\n", (void *)p, ref));
AdamGreen 0:616601bde9fb 664 /* stop walking through the chain */
AdamGreen 0:616601bde9fb 665 p = NULL;
AdamGreen 0:616601bde9fb 666 }
AdamGreen 0:616601bde9fb 667 }
AdamGreen 0:616601bde9fb 668 PERF_STOP("pbuf_free");
AdamGreen 0:616601bde9fb 669 /* return number of de-allocated pbufs */
AdamGreen 0:616601bde9fb 670 return count;
AdamGreen 0:616601bde9fb 671 }
AdamGreen 0:616601bde9fb 672
AdamGreen 0:616601bde9fb 673 /**
AdamGreen 0:616601bde9fb 674 * Count number of pbufs in a chain
AdamGreen 0:616601bde9fb 675 *
AdamGreen 0:616601bde9fb 676 * @param p first pbuf of chain
AdamGreen 0:616601bde9fb 677 * @return the number of pbufs in a chain
AdamGreen 0:616601bde9fb 678 */
AdamGreen 0:616601bde9fb 679
AdamGreen 0:616601bde9fb 680 u8_t
AdamGreen 0:616601bde9fb 681 pbuf_clen(struct pbuf *p)
AdamGreen 0:616601bde9fb 682 {
AdamGreen 0:616601bde9fb 683 u8_t len;
AdamGreen 0:616601bde9fb 684
AdamGreen 0:616601bde9fb 685 len = 0;
AdamGreen 0:616601bde9fb 686 while (p != NULL) {
AdamGreen 0:616601bde9fb 687 ++len;
AdamGreen 0:616601bde9fb 688 p = p->next;
AdamGreen 0:616601bde9fb 689 }
AdamGreen 0:616601bde9fb 690 return len;
AdamGreen 0:616601bde9fb 691 }
AdamGreen 0:616601bde9fb 692
AdamGreen 0:616601bde9fb 693 /**
AdamGreen 0:616601bde9fb 694 * Increment the reference count of the pbuf.
AdamGreen 0:616601bde9fb 695 *
AdamGreen 0:616601bde9fb 696 * @param p pbuf to increase reference counter of
AdamGreen 0:616601bde9fb 697 *
AdamGreen 0:616601bde9fb 698 */
AdamGreen 0:616601bde9fb 699 void
AdamGreen 0:616601bde9fb 700 pbuf_ref(struct pbuf *p)
AdamGreen 0:616601bde9fb 701 {
AdamGreen 0:616601bde9fb 702 SYS_ARCH_DECL_PROTECT(old_level);
AdamGreen 0:616601bde9fb 703 /* pbuf given? */
AdamGreen 0:616601bde9fb 704 if (p != NULL) {
AdamGreen 0:616601bde9fb 705 SYS_ARCH_PROTECT(old_level);
AdamGreen 0:616601bde9fb 706 ++(p->ref);
AdamGreen 0:616601bde9fb 707 SYS_ARCH_UNPROTECT(old_level);
AdamGreen 0:616601bde9fb 708 }
AdamGreen 0:616601bde9fb 709 }
AdamGreen 0:616601bde9fb 710
AdamGreen 0:616601bde9fb 711 /**
AdamGreen 0:616601bde9fb 712 * Concatenate two pbufs (each may be a pbuf chain) and take over
AdamGreen 0:616601bde9fb 713 * the caller's reference of the tail pbuf.
AdamGreen 0:616601bde9fb 714 *
AdamGreen 0:616601bde9fb 715 * @note The caller MAY NOT reference the tail pbuf afterwards.
AdamGreen 0:616601bde9fb 716 * Use pbuf_chain() for that purpose.
AdamGreen 0:616601bde9fb 717 *
AdamGreen 0:616601bde9fb 718 * @see pbuf_chain()
AdamGreen 0:616601bde9fb 719 */
AdamGreen 0:616601bde9fb 720
AdamGreen 0:616601bde9fb 721 void
AdamGreen 0:616601bde9fb 722 pbuf_cat(struct pbuf *h, struct pbuf *t)
AdamGreen 0:616601bde9fb 723 {
AdamGreen 0:616601bde9fb 724 struct pbuf *p;
AdamGreen 0:616601bde9fb 725
AdamGreen 0:616601bde9fb 726 LWIP_ERROR("(h != NULL) && (t != NULL) (programmer violates API)",
AdamGreen 0:616601bde9fb 727 ((h != NULL) && (t != NULL)), return;);
AdamGreen 0:616601bde9fb 728
AdamGreen 0:616601bde9fb 729 /* proceed to last pbuf of chain */
AdamGreen 0:616601bde9fb 730 for (p = h; p->next != NULL; p = p->next) {
AdamGreen 0:616601bde9fb 731 /* add total length of second chain to all totals of first chain */
AdamGreen 0:616601bde9fb 732 p->tot_len += t->tot_len;
AdamGreen 0:616601bde9fb 733 }
AdamGreen 0:616601bde9fb 734 /* { p is last pbuf of first h chain, p->next == NULL } */
AdamGreen 0:616601bde9fb 735 LWIP_ASSERT("p->tot_len == p->len (of last pbuf in chain)", p->tot_len == p->len);
AdamGreen 0:616601bde9fb 736 LWIP_ASSERT("p->next == NULL", p->next == NULL);
AdamGreen 0:616601bde9fb 737 /* add total length of second chain to last pbuf total of first chain */
AdamGreen 0:616601bde9fb 738 p->tot_len += t->tot_len;
AdamGreen 0:616601bde9fb 739 /* chain last pbuf of head (p) with first of tail (t) */
AdamGreen 0:616601bde9fb 740 p->next = t;
AdamGreen 0:616601bde9fb 741 /* p->next now references t, but the caller will drop its reference to t,
AdamGreen 0:616601bde9fb 742 * so netto there is no change to the reference count of t.
AdamGreen 0:616601bde9fb 743 */
AdamGreen 0:616601bde9fb 744 }
AdamGreen 0:616601bde9fb 745
AdamGreen 0:616601bde9fb 746 /**
AdamGreen 0:616601bde9fb 747 * Chain two pbufs (or pbuf chains) together.
AdamGreen 0:616601bde9fb 748 *
AdamGreen 0:616601bde9fb 749 * The caller MUST call pbuf_free(t) once it has stopped
AdamGreen 0:616601bde9fb 750 * using it. Use pbuf_cat() instead if you no longer use t.
AdamGreen 0:616601bde9fb 751 *
AdamGreen 0:616601bde9fb 752 * @param h head pbuf (chain)
AdamGreen 0:616601bde9fb 753 * @param t tail pbuf (chain)
AdamGreen 0:616601bde9fb 754 * @note The pbufs MUST belong to the same packet.
AdamGreen 0:616601bde9fb 755 * @note MAY NOT be called on a packet queue.
AdamGreen 0:616601bde9fb 756 *
AdamGreen 0:616601bde9fb 757 * The ->tot_len fields of all pbufs of the head chain are adjusted.
AdamGreen 0:616601bde9fb 758 * The ->next field of the last pbuf of the head chain is adjusted.
AdamGreen 0:616601bde9fb 759 * The ->ref field of the first pbuf of the tail chain is adjusted.
AdamGreen 0:616601bde9fb 760 *
AdamGreen 0:616601bde9fb 761 */
AdamGreen 0:616601bde9fb 762 void
AdamGreen 0:616601bde9fb 763 pbuf_chain(struct pbuf *h, struct pbuf *t)
AdamGreen 0:616601bde9fb 764 {
AdamGreen 0:616601bde9fb 765 pbuf_cat(h, t);
AdamGreen 0:616601bde9fb 766 /* t is now referenced by h */
AdamGreen 0:616601bde9fb 767 pbuf_ref(t);
AdamGreen 0:616601bde9fb 768 LWIP_DEBUGF(PBUF_DEBUG | LWIP_DBG_TRACE, ("pbuf_chain: %p references %p\n", (void *)h, (void *)t));
AdamGreen 0:616601bde9fb 769 }
AdamGreen 0:616601bde9fb 770
AdamGreen 0:616601bde9fb 771 /**
AdamGreen 0:616601bde9fb 772 * Dechains the first pbuf from its succeeding pbufs in the chain.
AdamGreen 0:616601bde9fb 773 *
AdamGreen 0:616601bde9fb 774 * Makes p->tot_len field equal to p->len.
AdamGreen 0:616601bde9fb 775 * @param p pbuf to dechain
AdamGreen 0:616601bde9fb 776 * @return remainder of the pbuf chain, or NULL if it was de-allocated.
AdamGreen 0:616601bde9fb 777 * @note May not be called on a packet queue.
AdamGreen 0:616601bde9fb 778 */
AdamGreen 0:616601bde9fb 779 struct pbuf *
AdamGreen 0:616601bde9fb 780 pbuf_dechain(struct pbuf *p)
AdamGreen 0:616601bde9fb 781 {
AdamGreen 0:616601bde9fb 782 struct pbuf *q;
AdamGreen 0:616601bde9fb 783 u8_t tail_gone = 1;
AdamGreen 0:616601bde9fb 784 /* tail */
AdamGreen 0:616601bde9fb 785 q = p->next;
AdamGreen 0:616601bde9fb 786 /* pbuf has successor in chain? */
AdamGreen 0:616601bde9fb 787 if (q != NULL) {
AdamGreen 0:616601bde9fb 788 /* assert tot_len invariant: (p->tot_len == p->len + (p->next? p->next->tot_len: 0) */
AdamGreen 0:616601bde9fb 789 LWIP_ASSERT("p->tot_len == p->len + q->tot_len", q->tot_len == p->tot_len - p->len);
AdamGreen 0:616601bde9fb 790 /* enforce invariant if assertion is disabled */
AdamGreen 0:616601bde9fb 791 q->tot_len = p->tot_len - p->len;
AdamGreen 0:616601bde9fb 792 /* decouple pbuf from remainder */
AdamGreen 0:616601bde9fb 793 p->next = NULL;
AdamGreen 0:616601bde9fb 794 /* total length of pbuf p is its own length only */
AdamGreen 0:616601bde9fb 795 p->tot_len = p->len;
AdamGreen 0:616601bde9fb 796 /* q is no longer referenced by p, free it */
AdamGreen 0:616601bde9fb 797 LWIP_DEBUGF(PBUF_DEBUG | LWIP_DBG_TRACE, ("pbuf_dechain: unreferencing %p\n", (void *)q));
AdamGreen 0:616601bde9fb 798 tail_gone = pbuf_free(q);
AdamGreen 0:616601bde9fb 799 if (tail_gone > 0) {
AdamGreen 0:616601bde9fb 800 LWIP_DEBUGF(PBUF_DEBUG | LWIP_DBG_TRACE,
AdamGreen 0:616601bde9fb 801 ("pbuf_dechain: deallocated %p (as it is no longer referenced)\n", (void *)q));
AdamGreen 0:616601bde9fb 802 }
AdamGreen 0:616601bde9fb 803 /* return remaining tail or NULL if deallocated */
AdamGreen 0:616601bde9fb 804 }
AdamGreen 0:616601bde9fb 805 /* assert tot_len invariant: (p->tot_len == p->len + (p->next? p->next->tot_len: 0) */
AdamGreen 0:616601bde9fb 806 LWIP_ASSERT("p->tot_len == p->len", p->tot_len == p->len);
AdamGreen 0:616601bde9fb 807 return ((tail_gone > 0) ? NULL : q);
AdamGreen 0:616601bde9fb 808 }
AdamGreen 0:616601bde9fb 809
AdamGreen 0:616601bde9fb 810 /**
AdamGreen 0:616601bde9fb 811 *
AdamGreen 0:616601bde9fb 812 * Create PBUF_RAM copies of pbufs.
AdamGreen 0:616601bde9fb 813 *
AdamGreen 0:616601bde9fb 814 * Used to queue packets on behalf of the lwIP stack, such as
AdamGreen 0:616601bde9fb 815 * ARP based queueing.
AdamGreen 0:616601bde9fb 816 *
AdamGreen 0:616601bde9fb 817 * @note You MUST explicitly use p = pbuf_take(p);
AdamGreen 0:616601bde9fb 818 *
AdamGreen 0:616601bde9fb 819 * @note Only one packet is copied, no packet queue!
AdamGreen 0:616601bde9fb 820 *
AdamGreen 0:616601bde9fb 821 * @param p_to pbuf destination of the copy
AdamGreen 0:616601bde9fb 822 * @param p_from pbuf source of the copy
AdamGreen 0:616601bde9fb 823 *
AdamGreen 0:616601bde9fb 824 * @return ERR_OK if pbuf was copied
AdamGreen 0:616601bde9fb 825 * ERR_ARG if one of the pbufs is NULL or p_to is not big
AdamGreen 0:616601bde9fb 826 * enough to hold p_from
AdamGreen 0:616601bde9fb 827 */
AdamGreen 0:616601bde9fb 828 err_t
AdamGreen 0:616601bde9fb 829 pbuf_copy(struct pbuf *p_to, struct pbuf *p_from)
AdamGreen 0:616601bde9fb 830 {
AdamGreen 0:616601bde9fb 831 u16_t offset_to=0, offset_from=0, len;
AdamGreen 0:616601bde9fb 832
AdamGreen 0:616601bde9fb 833 LWIP_DEBUGF(PBUF_DEBUG | LWIP_DBG_TRACE, ("pbuf_copy(%p, %p)\n",
AdamGreen 0:616601bde9fb 834 (void*)p_to, (void*)p_from));
AdamGreen 0:616601bde9fb 835
AdamGreen 0:616601bde9fb 836 /* is the target big enough to hold the source? */
AdamGreen 0:616601bde9fb 837 LWIP_ERROR("pbuf_copy: target not big enough to hold source", ((p_to != NULL) &&
AdamGreen 0:616601bde9fb 838 (p_from != NULL) && (p_to->tot_len >= p_from->tot_len)), return ERR_ARG;);
AdamGreen 0:616601bde9fb 839
AdamGreen 0:616601bde9fb 840 /* iterate through pbuf chain */
AdamGreen 0:616601bde9fb 841 do
AdamGreen 0:616601bde9fb 842 {
AdamGreen 0:616601bde9fb 843 LWIP_ASSERT("p_to != NULL", p_to != NULL);
AdamGreen 0:616601bde9fb 844 /* copy one part of the original chain */
AdamGreen 0:616601bde9fb 845 if ((p_to->len - offset_to) >= (p_from->len - offset_from)) {
AdamGreen 0:616601bde9fb 846 /* complete current p_from fits into current p_to */
AdamGreen 0:616601bde9fb 847 len = p_from->len - offset_from;
AdamGreen 0:616601bde9fb 848 } else {
AdamGreen 0:616601bde9fb 849 /* current p_from does not fit into current p_to */
AdamGreen 0:616601bde9fb 850 len = p_to->len - offset_to;
AdamGreen 0:616601bde9fb 851 }
AdamGreen 0:616601bde9fb 852 MEMCPY((u8_t*)p_to->payload + offset_to, (u8_t*)p_from->payload + offset_from, len);
AdamGreen 0:616601bde9fb 853 offset_to += len;
AdamGreen 0:616601bde9fb 854 offset_from += len;
AdamGreen 0:616601bde9fb 855 LWIP_ASSERT("offset_to <= p_to->len", offset_to <= p_to->len);
AdamGreen 0:616601bde9fb 856 if (offset_to == p_to->len) {
AdamGreen 0:616601bde9fb 857 /* on to next p_to (if any) */
AdamGreen 0:616601bde9fb 858 offset_to = 0;
AdamGreen 0:616601bde9fb 859 p_to = p_to->next;
AdamGreen 0:616601bde9fb 860 }
AdamGreen 0:616601bde9fb 861 LWIP_ASSERT("offset_from <= p_from->len", offset_from <= p_from->len);
AdamGreen 0:616601bde9fb 862 if (offset_from >= p_from->len) {
AdamGreen 0:616601bde9fb 863 /* on to next p_from (if any) */
AdamGreen 0:616601bde9fb 864 offset_from = 0;
AdamGreen 0:616601bde9fb 865 p_from = p_from->next;
AdamGreen 0:616601bde9fb 866 }
AdamGreen 0:616601bde9fb 867
AdamGreen 0:616601bde9fb 868 if((p_from != NULL) && (p_from->len == p_from->tot_len)) {
AdamGreen 0:616601bde9fb 869 /* don't copy more than one packet! */
AdamGreen 0:616601bde9fb 870 LWIP_ERROR("pbuf_copy() does not allow packet queues!\n",
AdamGreen 0:616601bde9fb 871 (p_from->next == NULL), return ERR_VAL;);
AdamGreen 0:616601bde9fb 872 }
AdamGreen 0:616601bde9fb 873 if((p_to != NULL) && (p_to->len == p_to->tot_len)) {
AdamGreen 0:616601bde9fb 874 /* don't copy more than one packet! */
AdamGreen 0:616601bde9fb 875 LWIP_ERROR("pbuf_copy() does not allow packet queues!\n",
AdamGreen 0:616601bde9fb 876 (p_to->next == NULL), return ERR_VAL;);
AdamGreen 0:616601bde9fb 877 }
AdamGreen 0:616601bde9fb 878 } while (p_from);
AdamGreen 0:616601bde9fb 879 LWIP_DEBUGF(PBUF_DEBUG | LWIP_DBG_TRACE, ("pbuf_copy: end of chain reached.\n"));
AdamGreen 0:616601bde9fb 880 return ERR_OK;
AdamGreen 0:616601bde9fb 881 }
AdamGreen 0:616601bde9fb 882
AdamGreen 0:616601bde9fb 883 /**
AdamGreen 0:616601bde9fb 884 * Copy (part of) the contents of a packet buffer
AdamGreen 0:616601bde9fb 885 * to an application supplied buffer.
AdamGreen 0:616601bde9fb 886 *
AdamGreen 0:616601bde9fb 887 * @param buf the pbuf from which to copy data
AdamGreen 0:616601bde9fb 888 * @param dataptr the application supplied buffer
AdamGreen 0:616601bde9fb 889 * @param len length of data to copy (dataptr must be big enough). No more
AdamGreen 0:616601bde9fb 890 * than buf->tot_len will be copied, irrespective of len
AdamGreen 0:616601bde9fb 891 * @param offset offset into the packet buffer from where to begin copying len bytes
AdamGreen 0:616601bde9fb 892 * @return the number of bytes copied, or 0 on failure
AdamGreen 0:616601bde9fb 893 */
AdamGreen 0:616601bde9fb 894 u16_t
AdamGreen 0:616601bde9fb 895 pbuf_copy_partial(struct pbuf *buf, void *dataptr, u16_t len, u16_t offset)
AdamGreen 0:616601bde9fb 896 {
AdamGreen 0:616601bde9fb 897 struct pbuf *p;
AdamGreen 0:616601bde9fb 898 u16_t left;
AdamGreen 0:616601bde9fb 899 u16_t buf_copy_len;
AdamGreen 0:616601bde9fb 900 u16_t copied_total = 0;
AdamGreen 0:616601bde9fb 901
AdamGreen 0:616601bde9fb 902 LWIP_ERROR("pbuf_copy_partial: invalid buf", (buf != NULL), return 0;);
AdamGreen 0:616601bde9fb 903 LWIP_ERROR("pbuf_copy_partial: invalid dataptr", (dataptr != NULL), return 0;);
AdamGreen 0:616601bde9fb 904
AdamGreen 0:616601bde9fb 905 left = 0;
AdamGreen 0:616601bde9fb 906
AdamGreen 0:616601bde9fb 907 if((buf == NULL) || (dataptr == NULL)) {
AdamGreen 0:616601bde9fb 908 return 0;
AdamGreen 0:616601bde9fb 909 }
AdamGreen 0:616601bde9fb 910
AdamGreen 0:616601bde9fb 911 /* Note some systems use byte copy if dataptr or one of the pbuf payload pointers are unaligned. */
AdamGreen 0:616601bde9fb 912 for(p = buf; len != 0 && p != NULL; p = p->next) {
AdamGreen 0:616601bde9fb 913 if ((offset != 0) && (offset >= p->len)) {
AdamGreen 0:616601bde9fb 914 /* don't copy from this buffer -> on to the next */
AdamGreen 0:616601bde9fb 915 offset -= p->len;
AdamGreen 0:616601bde9fb 916 } else {
AdamGreen 0:616601bde9fb 917 /* copy from this buffer. maybe only partially. */
AdamGreen 0:616601bde9fb 918 buf_copy_len = p->len - offset;
AdamGreen 0:616601bde9fb 919 if (buf_copy_len > len)
AdamGreen 0:616601bde9fb 920 buf_copy_len = len;
AdamGreen 0:616601bde9fb 921 /* copy the necessary parts of the buffer */
AdamGreen 0:616601bde9fb 922 MEMCPY(&((char*)dataptr)[left], &((char*)p->payload)[offset], buf_copy_len);
AdamGreen 0:616601bde9fb 923 copied_total += buf_copy_len;
AdamGreen 0:616601bde9fb 924 left += buf_copy_len;
AdamGreen 0:616601bde9fb 925 len -= buf_copy_len;
AdamGreen 0:616601bde9fb 926 offset = 0;
AdamGreen 0:616601bde9fb 927 }
AdamGreen 0:616601bde9fb 928 }
AdamGreen 0:616601bde9fb 929 return copied_total;
AdamGreen 0:616601bde9fb 930 }
AdamGreen 0:616601bde9fb 931
AdamGreen 0:616601bde9fb 932 /**
AdamGreen 0:616601bde9fb 933 * Copy application supplied data into a pbuf.
AdamGreen 0:616601bde9fb 934 * This function can only be used to copy the equivalent of buf->tot_len data.
AdamGreen 0:616601bde9fb 935 *
AdamGreen 0:616601bde9fb 936 * @param buf pbuf to fill with data
AdamGreen 0:616601bde9fb 937 * @param dataptr application supplied data buffer
AdamGreen 0:616601bde9fb 938 * @param len length of the application supplied data buffer
AdamGreen 0:616601bde9fb 939 *
AdamGreen 0:616601bde9fb 940 * @return ERR_OK if successful, ERR_MEM if the pbuf is not big enough
AdamGreen 0:616601bde9fb 941 */
AdamGreen 0:616601bde9fb 942 err_t
AdamGreen 0:616601bde9fb 943 pbuf_take(struct pbuf *buf, const void *dataptr, u16_t len)
AdamGreen 0:616601bde9fb 944 {
AdamGreen 0:616601bde9fb 945 struct pbuf *p;
AdamGreen 0:616601bde9fb 946 u16_t buf_copy_len;
AdamGreen 0:616601bde9fb 947 u16_t total_copy_len = len;
AdamGreen 0:616601bde9fb 948 u16_t copied_total = 0;
AdamGreen 0:616601bde9fb 949
AdamGreen 0:616601bde9fb 950 LWIP_ERROR("pbuf_take: invalid buf", (buf != NULL), return 0;);
AdamGreen 0:616601bde9fb 951 LWIP_ERROR("pbuf_take: invalid dataptr", (dataptr != NULL), return 0;);
AdamGreen 0:616601bde9fb 952
AdamGreen 0:616601bde9fb 953 if ((buf == NULL) || (dataptr == NULL) || (buf->tot_len < len)) {
AdamGreen 0:616601bde9fb 954 return ERR_ARG;
AdamGreen 0:616601bde9fb 955 }
AdamGreen 0:616601bde9fb 956
AdamGreen 0:616601bde9fb 957 /* Note some systems use byte copy if dataptr or one of the pbuf payload pointers are unaligned. */
AdamGreen 0:616601bde9fb 958 for(p = buf; total_copy_len != 0; p = p->next) {
AdamGreen 0:616601bde9fb 959 LWIP_ASSERT("pbuf_take: invalid pbuf", p != NULL);
AdamGreen 0:616601bde9fb 960 buf_copy_len = total_copy_len;
AdamGreen 0:616601bde9fb 961 if (buf_copy_len > p->len) {
AdamGreen 0:616601bde9fb 962 /* this pbuf cannot hold all remaining data */
AdamGreen 0:616601bde9fb 963 buf_copy_len = p->len;
AdamGreen 0:616601bde9fb 964 }
AdamGreen 0:616601bde9fb 965 /* copy the necessary parts of the buffer */
AdamGreen 0:616601bde9fb 966 MEMCPY(p->payload, &((char*)dataptr)[copied_total], buf_copy_len);
AdamGreen 0:616601bde9fb 967 total_copy_len -= buf_copy_len;
AdamGreen 0:616601bde9fb 968 copied_total += buf_copy_len;
AdamGreen 0:616601bde9fb 969 }
AdamGreen 0:616601bde9fb 970 LWIP_ASSERT("did not copy all data", total_copy_len == 0 && copied_total == len);
AdamGreen 0:616601bde9fb 971 return ERR_OK;
AdamGreen 0:616601bde9fb 972 }
AdamGreen 0:616601bde9fb 973
AdamGreen 0:616601bde9fb 974 /**
AdamGreen 0:616601bde9fb 975 * Creates a single pbuf out of a queue of pbufs.
AdamGreen 0:616601bde9fb 976 *
AdamGreen 0:616601bde9fb 977 * @remark: Either the source pbuf 'p' is freed by this function or the original
AdamGreen 0:616601bde9fb 978 * pbuf 'p' is returned, therefore the caller has to check the result!
AdamGreen 0:616601bde9fb 979 *
AdamGreen 0:616601bde9fb 980 * @param p the source pbuf
AdamGreen 0:616601bde9fb 981 * @param layer pbuf_layer of the new pbuf
AdamGreen 0:616601bde9fb 982 *
AdamGreen 0:616601bde9fb 983 * @return a new, single pbuf (p->next is NULL)
AdamGreen 0:616601bde9fb 984 * or the old pbuf if allocation fails
AdamGreen 0:616601bde9fb 985 */
AdamGreen 0:616601bde9fb 986 struct pbuf*
AdamGreen 0:616601bde9fb 987 pbuf_coalesce(struct pbuf *p, pbuf_layer layer)
AdamGreen 0:616601bde9fb 988 {
AdamGreen 0:616601bde9fb 989 struct pbuf *q;
AdamGreen 0:616601bde9fb 990 err_t err;
AdamGreen 0:616601bde9fb 991 if (p->next == NULL) {
AdamGreen 0:616601bde9fb 992 return p;
AdamGreen 0:616601bde9fb 993 }
AdamGreen 0:616601bde9fb 994 q = pbuf_alloc(layer, p->tot_len, PBUF_RAM);
AdamGreen 0:616601bde9fb 995 if (q == NULL) {
AdamGreen 0:616601bde9fb 996 /* @todo: what do we do now? */
AdamGreen 0:616601bde9fb 997 return p;
AdamGreen 0:616601bde9fb 998 }
AdamGreen 0:616601bde9fb 999 err = pbuf_copy(q, p);
AdamGreen 0:616601bde9fb 1000 LWIP_ASSERT("pbuf_copy failed", err == ERR_OK);
AdamGreen 0:616601bde9fb 1001 pbuf_free(p);
AdamGreen 0:616601bde9fb 1002 return q;
AdamGreen 0:616601bde9fb 1003 }
AdamGreen 0:616601bde9fb 1004
AdamGreen 0:616601bde9fb 1005 #if LWIP_CHECKSUM_ON_COPY
AdamGreen 0:616601bde9fb 1006 /**
AdamGreen 0:616601bde9fb 1007 * Copies data into a single pbuf (*not* into a pbuf queue!) and updates
AdamGreen 0:616601bde9fb 1008 * the checksum while copying
AdamGreen 0:616601bde9fb 1009 *
AdamGreen 0:616601bde9fb 1010 * @param p the pbuf to copy data into
AdamGreen 0:616601bde9fb 1011 * @param start_offset offset of p->payload where to copy the data to
AdamGreen 0:616601bde9fb 1012 * @param dataptr data to copy into the pbuf
AdamGreen 0:616601bde9fb 1013 * @param len length of data to copy into the pbuf
AdamGreen 0:616601bde9fb 1014 * @param chksum pointer to the checksum which is updated
AdamGreen 0:616601bde9fb 1015 * @return ERR_OK if successful, another error if the data does not fit
AdamGreen 0:616601bde9fb 1016 * within the (first) pbuf (no pbuf queues!)
AdamGreen 0:616601bde9fb 1017 */
AdamGreen 0:616601bde9fb 1018 err_t
AdamGreen 0:616601bde9fb 1019 pbuf_fill_chksum(struct pbuf *p, u16_t start_offset, const void *dataptr,
AdamGreen 0:616601bde9fb 1020 u16_t len, u16_t *chksum)
AdamGreen 0:616601bde9fb 1021 {
AdamGreen 0:616601bde9fb 1022 u32_t acc;
AdamGreen 0:616601bde9fb 1023 u16_t copy_chksum;
AdamGreen 0:616601bde9fb 1024 char *dst_ptr;
AdamGreen 0:616601bde9fb 1025 LWIP_ASSERT("p != NULL", p != NULL);
AdamGreen 0:616601bde9fb 1026 LWIP_ASSERT("dataptr != NULL", dataptr != NULL);
AdamGreen 0:616601bde9fb 1027 LWIP_ASSERT("chksum != NULL", chksum != NULL);
AdamGreen 0:616601bde9fb 1028 LWIP_ASSERT("len != 0", len != 0);
AdamGreen 0:616601bde9fb 1029
AdamGreen 0:616601bde9fb 1030 if ((start_offset >= p->len) || (start_offset + len > p->len)) {
AdamGreen 0:616601bde9fb 1031 return ERR_ARG;
AdamGreen 0:616601bde9fb 1032 }
AdamGreen 0:616601bde9fb 1033
AdamGreen 0:616601bde9fb 1034 dst_ptr = ((char*)p->payload) + start_offset;
AdamGreen 0:616601bde9fb 1035 copy_chksum = LWIP_CHKSUM_COPY(dst_ptr, dataptr, len);
AdamGreen 0:616601bde9fb 1036 if ((start_offset & 1) != 0) {
AdamGreen 0:616601bde9fb 1037 copy_chksum = SWAP_BYTES_IN_WORD(copy_chksum);
AdamGreen 0:616601bde9fb 1038 }
AdamGreen 0:616601bde9fb 1039 acc = *chksum;
AdamGreen 0:616601bde9fb 1040 acc += copy_chksum;
AdamGreen 0:616601bde9fb 1041 *chksum = FOLD_U32T(acc);
AdamGreen 0:616601bde9fb 1042 return ERR_OK;
AdamGreen 0:616601bde9fb 1043 }
AdamGreen 0:616601bde9fb 1044 #endif /* LWIP_CHECKSUM_ON_COPY */
AdamGreen 0:616601bde9fb 1045
AdamGreen 0:616601bde9fb 1046 /** Get one byte from the specified position in a pbuf
AdamGreen 0:616601bde9fb 1047 * WARNING: returns zero for offset >= p->tot_len
AdamGreen 0:616601bde9fb 1048 *
AdamGreen 0:616601bde9fb 1049 * @param p pbuf to parse
AdamGreen 0:616601bde9fb 1050 * @param offset offset into p of the byte to return
AdamGreen 0:616601bde9fb 1051 * @return byte at an offset into p OR ZERO IF 'offset' >= p->tot_len
AdamGreen 0:616601bde9fb 1052 */
AdamGreen 0:616601bde9fb 1053 u8_t
AdamGreen 0:616601bde9fb 1054 pbuf_get_at(struct pbuf* p, u16_t offset)
AdamGreen 0:616601bde9fb 1055 {
AdamGreen 0:616601bde9fb 1056 u16_t copy_from = offset;
AdamGreen 0:616601bde9fb 1057 struct pbuf* q = p;
AdamGreen 0:616601bde9fb 1058
AdamGreen 0:616601bde9fb 1059 /* get the correct pbuf */
AdamGreen 0:616601bde9fb 1060 while ((q != NULL) && (q->len <= copy_from)) {
AdamGreen 0:616601bde9fb 1061 copy_from -= q->len;
AdamGreen 0:616601bde9fb 1062 q = q->next;
AdamGreen 0:616601bde9fb 1063 }
AdamGreen 0:616601bde9fb 1064 /* return requested data if pbuf is OK */
AdamGreen 0:616601bde9fb 1065 if ((q != NULL) && (q->len > copy_from)) {
AdamGreen 0:616601bde9fb 1066 return ((u8_t*)q->payload)[copy_from];
AdamGreen 0:616601bde9fb 1067 }
AdamGreen 0:616601bde9fb 1068 return 0;
AdamGreen 0:616601bde9fb 1069 }
AdamGreen 0:616601bde9fb 1070
AdamGreen 0:616601bde9fb 1071 /** Compare pbuf contents at specified offset with memory s2, both of length n
AdamGreen 0:616601bde9fb 1072 *
AdamGreen 0:616601bde9fb 1073 * @param p pbuf to compare
AdamGreen 0:616601bde9fb 1074 * @param offset offset into p at wich to start comparing
AdamGreen 0:616601bde9fb 1075 * @param s2 buffer to compare
AdamGreen 0:616601bde9fb 1076 * @param n length of buffer to compare
AdamGreen 0:616601bde9fb 1077 * @return zero if equal, nonzero otherwise
AdamGreen 0:616601bde9fb 1078 * (0xffff if p is too short, diffoffset+1 otherwise)
AdamGreen 0:616601bde9fb 1079 */
AdamGreen 0:616601bde9fb 1080 u16_t
AdamGreen 0:616601bde9fb 1081 pbuf_memcmp(struct pbuf* p, u16_t offset, const void* s2, u16_t n)
AdamGreen 0:616601bde9fb 1082 {
AdamGreen 0:616601bde9fb 1083 u16_t start = offset;
AdamGreen 0:616601bde9fb 1084 struct pbuf* q = p;
AdamGreen 0:616601bde9fb 1085
AdamGreen 0:616601bde9fb 1086 /* get the correct pbuf */
AdamGreen 0:616601bde9fb 1087 while ((q != NULL) && (q->len <= start)) {
AdamGreen 0:616601bde9fb 1088 start -= q->len;
AdamGreen 0:616601bde9fb 1089 q = q->next;
AdamGreen 0:616601bde9fb 1090 }
AdamGreen 0:616601bde9fb 1091 /* return requested data if pbuf is OK */
AdamGreen 0:616601bde9fb 1092 if ((q != NULL) && (q->len > start)) {
AdamGreen 0:616601bde9fb 1093 u16_t i;
AdamGreen 0:616601bde9fb 1094 for(i = 0; i < n; i++) {
AdamGreen 0:616601bde9fb 1095 u8_t a = pbuf_get_at(q, start + i);
AdamGreen 0:616601bde9fb 1096 u8_t b = ((u8_t*)s2)[i];
AdamGreen 0:616601bde9fb 1097 if (a != b) {
AdamGreen 0:616601bde9fb 1098 return i+1;
AdamGreen 0:616601bde9fb 1099 }
AdamGreen 0:616601bde9fb 1100 }
AdamGreen 0:616601bde9fb 1101 return 0;
AdamGreen 0:616601bde9fb 1102 }
AdamGreen 0:616601bde9fb 1103 return 0xffff;
AdamGreen 0:616601bde9fb 1104 }
AdamGreen 0:616601bde9fb 1105
AdamGreen 0:616601bde9fb 1106 /** Find occurrence of mem (with length mem_len) in pbuf p, starting at offset
AdamGreen 0:616601bde9fb 1107 * start_offset.
AdamGreen 0:616601bde9fb 1108 *
AdamGreen 0:616601bde9fb 1109 * @param p pbuf to search, maximum length is 0xFFFE since 0xFFFF is used as
AdamGreen 0:616601bde9fb 1110 * return value 'not found'
AdamGreen 0:616601bde9fb 1111 * @param mem search for the contents of this buffer
AdamGreen 0:616601bde9fb 1112 * @param mem_len length of 'mem'
AdamGreen 0:616601bde9fb 1113 * @param start_offset offset into p at which to start searching
AdamGreen 0:616601bde9fb 1114 * @return 0xFFFF if substr was not found in p or the index where it was found
AdamGreen 0:616601bde9fb 1115 */
AdamGreen 0:616601bde9fb 1116 u16_t
AdamGreen 0:616601bde9fb 1117 pbuf_memfind(struct pbuf* p, const void* mem, u16_t mem_len, u16_t start_offset)
AdamGreen 0:616601bde9fb 1118 {
AdamGreen 0:616601bde9fb 1119 u16_t i;
AdamGreen 0:616601bde9fb 1120 u16_t max = p->tot_len - mem_len;
AdamGreen 0:616601bde9fb 1121 if (p->tot_len >= mem_len + start_offset) {
AdamGreen 0:616601bde9fb 1122 for(i = start_offset; i <= max; ) {
AdamGreen 0:616601bde9fb 1123 u16_t plus = pbuf_memcmp(p, i, mem, mem_len);
AdamGreen 0:616601bde9fb 1124 if (plus == 0) {
AdamGreen 0:616601bde9fb 1125 return i;
AdamGreen 0:616601bde9fb 1126 } else {
AdamGreen 0:616601bde9fb 1127 i += plus;
AdamGreen 0:616601bde9fb 1128 }
AdamGreen 0:616601bde9fb 1129 }
AdamGreen 0:616601bde9fb 1130 }
AdamGreen 0:616601bde9fb 1131 return 0xFFFF;
AdamGreen 0:616601bde9fb 1132 }
AdamGreen 0:616601bde9fb 1133
AdamGreen 0:616601bde9fb 1134 /** Find occurrence of substr with length substr_len in pbuf p, start at offset
AdamGreen 0:616601bde9fb 1135 * start_offset
AdamGreen 0:616601bde9fb 1136 * WARNING: in contrast to strstr(), this one does not stop at the first \0 in
AdamGreen 0:616601bde9fb 1137 * the pbuf/source string!
AdamGreen 0:616601bde9fb 1138 *
AdamGreen 0:616601bde9fb 1139 * @param p pbuf to search, maximum length is 0xFFFE since 0xFFFF is used as
AdamGreen 0:616601bde9fb 1140 * return value 'not found'
AdamGreen 0:616601bde9fb 1141 * @param substr string to search for in p, maximum length is 0xFFFE
AdamGreen 0:616601bde9fb 1142 * @return 0xFFFF if substr was not found in p or the index where it was found
AdamGreen 0:616601bde9fb 1143 */
AdamGreen 0:616601bde9fb 1144 u16_t
AdamGreen 0:616601bde9fb 1145 pbuf_strstr(struct pbuf* p, const char* substr)
AdamGreen 0:616601bde9fb 1146 {
AdamGreen 0:616601bde9fb 1147 size_t substr_len;
AdamGreen 0:616601bde9fb 1148 if ((substr == NULL) || (substr[0] == 0) || (p->tot_len == 0xFFFF)) {
AdamGreen 0:616601bde9fb 1149 return 0xFFFF;
AdamGreen 0:616601bde9fb 1150 }
AdamGreen 0:616601bde9fb 1151 substr_len = strlen(substr);
AdamGreen 0:616601bde9fb 1152 if (substr_len >= 0xFFFF) {
AdamGreen 0:616601bde9fb 1153 return 0xFFFF;
AdamGreen 0:616601bde9fb 1154 }
AdamGreen 0:616601bde9fb 1155 return pbuf_memfind(p, substr, (u16_t)substr_len, 0);
AdamGreen 0:616601bde9fb 1156 }