Lorcan Smith / Mbed 2 deprecated Enet_SPI

SNMP agent attached to SPI slave

Dependencies:   mbed

lwip/core/pbuf.c@0:2a53a4c3238c, 2012-08-13 (annotated)

Committer:
lorcansmith
Date:
Mon Aug 13 15:07:40 2012 +0000
Revision:
0:2a53a4c3238c
v1.1 release includes ioAlarm traps

Who changed what in which revision?

UserRevisionLine numberNew contents of line
lorcansmith 0:2a53a4c3238c 1 /**
lorcansmith 0:2a53a4c3238c 2 * @file
lorcansmith 0:2a53a4c3238c 3 * Packet buffer management
lorcansmith 0:2a53a4c3238c 4 *
lorcansmith 0:2a53a4c3238c 5 * Packets are built from the pbuf data structure. It supports dynamic
lorcansmith 0:2a53a4c3238c 6 * memory allocation for packet contents or can reference externally
lorcansmith 0:2a53a4c3238c 7 * managed packet contents both in RAM and ROM. Quick allocation for
lorcansmith 0:2a53a4c3238c 8 * incoming packets is provided through pools with fixed sized pbufs.
lorcansmith 0:2a53a4c3238c 9 *
lorcansmith 0:2a53a4c3238c 10 * A packet may span over multiple pbufs, chained as a singly linked
lorcansmith 0:2a53a4c3238c 11 * list. This is called a "pbuf chain".
lorcansmith 0:2a53a4c3238c 12 *
lorcansmith 0:2a53a4c3238c 13 * Multiple packets may be queued, also using this singly linked list.
lorcansmith 0:2a53a4c3238c 14 * This is called a "packet queue".
lorcansmith 0:2a53a4c3238c 15 *
lorcansmith 0:2a53a4c3238c 16 * So, a packet queue consists of one or more pbuf chains, each of
lorcansmith 0:2a53a4c3238c 17 * which consist of one or more pbufs. CURRENTLY, PACKET QUEUES ARE
lorcansmith 0:2a53a4c3238c 18 * NOT SUPPORTED!!! Use helper structs to queue multiple packets.
lorcansmith 0:2a53a4c3238c 19 *
lorcansmith 0:2a53a4c3238c 20 * The differences between a pbuf chain and a packet queue are very
lorcansmith 0:2a53a4c3238c 21 * precise but subtle.
lorcansmith 0:2a53a4c3238c 22 *
lorcansmith 0:2a53a4c3238c 23 * The last pbuf of a packet has a ->tot_len field that equals the
lorcansmith 0:2a53a4c3238c 24 * ->len field. It can be found by traversing the list. If the last
lorcansmith 0:2a53a4c3238c 25 * pbuf of a packet has a ->next field other than NULL, more packets
lorcansmith 0:2a53a4c3238c 26 * are on the queue.
lorcansmith 0:2a53a4c3238c 27 *
lorcansmith 0:2a53a4c3238c 28 * Therefore, looping through a pbuf of a single packet, has an
lorcansmith 0:2a53a4c3238c 29 * loop end condition (tot_len == p->len), NOT (next == NULL).
lorcansmith 0:2a53a4c3238c 30 */
lorcansmith 0:2a53a4c3238c 31
lorcansmith 0:2a53a4c3238c 32 /*
lorcansmith 0:2a53a4c3238c 33 * Copyright (c) 2001-2004 Swedish Institute of Computer Science.
lorcansmith 0:2a53a4c3238c 34 * All rights reserved.
lorcansmith 0:2a53a4c3238c 35 *
lorcansmith 0:2a53a4c3238c 36 * Redistribution and use in source and binary forms, with or without modification,
lorcansmith 0:2a53a4c3238c 37 * are permitted provided that the following conditions are met:
lorcansmith 0:2a53a4c3238c 38 *
lorcansmith 0:2a53a4c3238c 39 * 1. Redistributions of source code must retain the above copyright notice,
lorcansmith 0:2a53a4c3238c 40 * this list of conditions and the following disclaimer.
lorcansmith 0:2a53a4c3238c 41 * 2. Redistributions in binary form must reproduce the above copyright notice,
lorcansmith 0:2a53a4c3238c 42 * this list of conditions and the following disclaimer in the documentation
lorcansmith 0:2a53a4c3238c 43 * and/or other materials provided with the distribution.
lorcansmith 0:2a53a4c3238c 44 * 3. The name of the author may not be used to endorse or promote products
lorcansmith 0:2a53a4c3238c 45 * derived from this software without specific prior written permission.
lorcansmith 0:2a53a4c3238c 46 *
lorcansmith 0:2a53a4c3238c 47 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR IMPLIED
lorcansmith 0:2a53a4c3238c 48 * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
lorcansmith 0:2a53a4c3238c 49 * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT
lorcansmith 0:2a53a4c3238c 50 * SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
lorcansmith 0:2a53a4c3238c 51 * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT
lorcansmith 0:2a53a4c3238c 52 * OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
lorcansmith 0:2a53a4c3238c 53 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
lorcansmith 0:2a53a4c3238c 54 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
lorcansmith 0:2a53a4c3238c 55 * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY
lorcansmith 0:2a53a4c3238c 56 * OF SUCH DAMAGE.
lorcansmith 0:2a53a4c3238c 57 *
lorcansmith 0:2a53a4c3238c 58 * This file is part of the lwIP TCP/IP stack.
lorcansmith 0:2a53a4c3238c 59 *
lorcansmith 0:2a53a4c3238c 60 * Author: Adam Dunkels <adam@sics.se>
lorcansmith 0:2a53a4c3238c 61 *
lorcansmith 0:2a53a4c3238c 62 */
lorcansmith 0:2a53a4c3238c 63
lorcansmith 0:2a53a4c3238c 64 #include "lwip/opt.h"
lorcansmith 0:2a53a4c3238c 65
lorcansmith 0:2a53a4c3238c 66 #include "lwip/stats.h"
lorcansmith 0:2a53a4c3238c 67 #include "lwip/def.h"
lorcansmith 0:2a53a4c3238c 68 #include "lwip/mem.h"
lorcansmith 0:2a53a4c3238c 69 #include "lwip/memp.h"
lorcansmith 0:2a53a4c3238c 70 #include "lwip/pbuf.h"
lorcansmith 0:2a53a4c3238c 71 #include "lwip/sys.h"
lorcansmith 0:2a53a4c3238c 72 #include "arch/perf.h"
lorcansmith 0:2a53a4c3238c 73 #if TCP_QUEUE_OOSEQ
lorcansmith 0:2a53a4c3238c 74 #include "lwip/tcp_impl.h"
lorcansmith 0:2a53a4c3238c 75 #endif
lorcansmith 0:2a53a4c3238c 76 #if LWIP_CHECKSUM_ON_COPY
lorcansmith 0:2a53a4c3238c 77 #include "lwip/inet_chksum.h"
lorcansmith 0:2a53a4c3238c 78 #endif
lorcansmith 0:2a53a4c3238c 79
lorcansmith 0:2a53a4c3238c 80 #include <string.h>
lorcansmith 0:2a53a4c3238c 81
lorcansmith 0:2a53a4c3238c 82 #define SIZEOF_STRUCT_PBUF LWIP_MEM_ALIGN_SIZE(sizeof(struct pbuf))
lorcansmith 0:2a53a4c3238c 83 /* Since the pool is created in memp, PBUF_POOL_BUFSIZE will be automatically
lorcansmith 0:2a53a4c3238c 84 aligned there. Therefore, PBUF_POOL_BUFSIZE_ALIGNED can be used here. */
lorcansmith 0:2a53a4c3238c 85 #define PBUF_POOL_BUFSIZE_ALIGNED LWIP_MEM_ALIGN_SIZE(PBUF_POOL_BUFSIZE)
lorcansmith 0:2a53a4c3238c 86
lorcansmith 0:2a53a4c3238c 87 #if !LWIP_TCP || !TCP_QUEUE_OOSEQ || NO_SYS
lorcansmith 0:2a53a4c3238c 88 #define PBUF_POOL_IS_EMPTY()
lorcansmith 0:2a53a4c3238c 89 #else /* !LWIP_TCP || !TCP_QUEUE_OOSEQ || NO_SYS */
lorcansmith 0:2a53a4c3238c 90 /** Define this to 0 to prevent freeing ooseq pbufs when the PBUF_POOL is empty */
lorcansmith 0:2a53a4c3238c 91 #ifndef PBUF_POOL_FREE_OOSEQ
lorcansmith 0:2a53a4c3238c 92 #define PBUF_POOL_FREE_OOSEQ 1
lorcansmith 0:2a53a4c3238c 93 #endif /* PBUF_POOL_FREE_OOSEQ */
lorcansmith 0:2a53a4c3238c 94
lorcansmith 0:2a53a4c3238c 95 #if PBUF_POOL_FREE_OOSEQ
lorcansmith 0:2a53a4c3238c 96 #include "lwip/tcpip.h"
lorcansmith 0:2a53a4c3238c 97 #define PBUF_POOL_IS_EMPTY() pbuf_pool_is_empty()
lorcansmith 0:2a53a4c3238c 98 static u8_t pbuf_free_ooseq_queued;
lorcansmith 0:2a53a4c3238c 99 /**
lorcansmith 0:2a53a4c3238c 100 * Attempt to reclaim some memory from queued out-of-sequence TCP segments
lorcansmith 0:2a53a4c3238c 101 * if we run out of pool pbufs. It's better to give priority to new packets
lorcansmith 0:2a53a4c3238c 102 * if we're running out.
lorcansmith 0:2a53a4c3238c 103 *
lorcansmith 0:2a53a4c3238c 104 * This must be done in the correct thread context therefore this function
lorcansmith 0:2a53a4c3238c 105 * can only be used with NO_SYS=0 and through tcpip_callback.
lorcansmith 0:2a53a4c3238c 106 */
lorcansmith 0:2a53a4c3238c 107 static void
lorcansmith 0:2a53a4c3238c 108 pbuf_free_ooseq(void* arg)
lorcansmith 0:2a53a4c3238c 109 {
lorcansmith 0:2a53a4c3238c 110 struct tcp_pcb* pcb;
lorcansmith 0:2a53a4c3238c 111 SYS_ARCH_DECL_PROTECT(old_level);
lorcansmith 0:2a53a4c3238c 112 LWIP_UNUSED_ARG(arg);
lorcansmith 0:2a53a4c3238c 113
lorcansmith 0:2a53a4c3238c 114 SYS_ARCH_PROTECT(old_level);
lorcansmith 0:2a53a4c3238c 115 pbuf_free_ooseq_queued = 0;
lorcansmith 0:2a53a4c3238c 116 SYS_ARCH_UNPROTECT(old_level);
lorcansmith 0:2a53a4c3238c 117
lorcansmith 0:2a53a4c3238c 118 for (pcb = tcp_active_pcbs; NULL != pcb; pcb = pcb->next) {
lorcansmith 0:2a53a4c3238c 119 if (NULL != pcb->ooseq) {
lorcansmith 0:2a53a4c3238c 120 /** Free the ooseq pbufs of one PCB only */
lorcansmith 0:2a53a4c3238c 121 LWIP_DEBUGF(PBUF_DEBUG | LWIP_DBG_TRACE, ("pbuf_free_ooseq: freeing out-of-sequence pbufs\n"));
lorcansmith 0:2a53a4c3238c 122 tcp_segs_free(pcb->ooseq);
lorcansmith 0:2a53a4c3238c 123 pcb->ooseq = NULL;
lorcansmith 0:2a53a4c3238c 124 return;
lorcansmith 0:2a53a4c3238c 125 }
lorcansmith 0:2a53a4c3238c 126 }
lorcansmith 0:2a53a4c3238c 127 }
lorcansmith 0:2a53a4c3238c 128
lorcansmith 0:2a53a4c3238c 129 /** Queue a call to pbuf_free_ooseq if not already queued. */
lorcansmith 0:2a53a4c3238c 130 static void
lorcansmith 0:2a53a4c3238c 131 pbuf_pool_is_empty(void)
lorcansmith 0:2a53a4c3238c 132 {
lorcansmith 0:2a53a4c3238c 133 u8_t queued;
lorcansmith 0:2a53a4c3238c 134 SYS_ARCH_DECL_PROTECT(old_level);
lorcansmith 0:2a53a4c3238c 135
lorcansmith 0:2a53a4c3238c 136 SYS_ARCH_PROTECT(old_level);
lorcansmith 0:2a53a4c3238c 137 queued = pbuf_free_ooseq_queued;
lorcansmith 0:2a53a4c3238c 138 pbuf_free_ooseq_queued = 1;
lorcansmith 0:2a53a4c3238c 139 SYS_ARCH_UNPROTECT(old_level);
lorcansmith 0:2a53a4c3238c 140
lorcansmith 0:2a53a4c3238c 141 if(!queued) {
lorcansmith 0:2a53a4c3238c 142 /* queue a call to pbuf_free_ooseq if not already queued */
lorcansmith 0:2a53a4c3238c 143 if(tcpip_callback_with_block(pbuf_free_ooseq, NULL, 0) != ERR_OK) {
lorcansmith 0:2a53a4c3238c 144 SYS_ARCH_PROTECT(old_level);
lorcansmith 0:2a53a4c3238c 145 pbuf_free_ooseq_queued = 0;
lorcansmith 0:2a53a4c3238c 146 SYS_ARCH_UNPROTECT(old_level);
lorcansmith 0:2a53a4c3238c 147 }
lorcansmith 0:2a53a4c3238c 148 }
lorcansmith 0:2a53a4c3238c 149 }
lorcansmith 0:2a53a4c3238c 150 #endif /* PBUF_POOL_FREE_OOSEQ */
lorcansmith 0:2a53a4c3238c 151 #endif /* !LWIP_TCP || !TCP_QUEUE_OOSEQ || NO_SYS */
lorcansmith 0:2a53a4c3238c 152
lorcansmith 0:2a53a4c3238c 153 /**
lorcansmith 0:2a53a4c3238c 154 * Allocates a pbuf of the given type (possibly a chain for PBUF_POOL type).
lorcansmith 0:2a53a4c3238c 155 *
lorcansmith 0:2a53a4c3238c 156 * The actual memory allocated for the pbuf is determined by the
lorcansmith 0:2a53a4c3238c 157 * layer at which the pbuf is allocated and the requested size
lorcansmith 0:2a53a4c3238c 158 * (from the size parameter).
lorcansmith 0:2a53a4c3238c 159 *
lorcansmith 0:2a53a4c3238c 160 * @param layer flag to define header size
lorcansmith 0:2a53a4c3238c 161 * @param length size of the pbuf's payload
lorcansmith 0:2a53a4c3238c 162 * @param type this parameter decides how and where the pbuf
lorcansmith 0:2a53a4c3238c 163 * should be allocated as follows:
lorcansmith 0:2a53a4c3238c 164 *
lorcansmith 0:2a53a4c3238c 165 * - PBUF_RAM: buffer memory for pbuf is allocated as one large
lorcansmith 0:2a53a4c3238c 166 * chunk. This includes protocol headers as well.
lorcansmith 0:2a53a4c3238c 167 * - PBUF_ROM: no buffer memory is allocated for the pbuf, even for
lorcansmith 0:2a53a4c3238c 168 * protocol headers. Additional headers must be prepended
lorcansmith 0:2a53a4c3238c 169 * by allocating another pbuf and chain in to the front of
lorcansmith 0:2a53a4c3238c 170 * the ROM pbuf. It is assumed that the memory used is really
lorcansmith 0:2a53a4c3238c 171 * similar to ROM in that it is immutable and will not be
lorcansmith 0:2a53a4c3238c 172 * changed. Memory which is dynamic should generally not
lorcansmith 0:2a53a4c3238c 173 * be attached to PBUF_ROM pbufs. Use PBUF_REF instead.
lorcansmith 0:2a53a4c3238c 174 * - PBUF_REF: no buffer memory is allocated for the pbuf, even for
lorcansmith 0:2a53a4c3238c 175 * protocol headers. It is assumed that the pbuf is only
lorcansmith 0:2a53a4c3238c 176 * being used in a single thread. If the pbuf gets queued,
lorcansmith 0:2a53a4c3238c 177 * then pbuf_take should be called to copy the buffer.
lorcansmith 0:2a53a4c3238c 178 * - PBUF_POOL: the pbuf is allocated as a pbuf chain, with pbufs from
lorcansmith 0:2a53a4c3238c 179 * the pbuf pool that is allocated during pbuf_init().
lorcansmith 0:2a53a4c3238c 180 *
lorcansmith 0:2a53a4c3238c 181 * @return the allocated pbuf. If multiple pbufs where allocated, this
lorcansmith 0:2a53a4c3238c 182 * is the first pbuf of a pbuf chain.
lorcansmith 0:2a53a4c3238c 183 */
lorcansmith 0:2a53a4c3238c 184 struct pbuf *
lorcansmith 0:2a53a4c3238c 185 pbuf_alloc(pbuf_layer layer, u16_t length, pbuf_type type)
lorcansmith 0:2a53a4c3238c 186 {
lorcansmith 0:2a53a4c3238c 187 struct pbuf *p, *q, *r;
lorcansmith 0:2a53a4c3238c 188 u16_t offset;
lorcansmith 0:2a53a4c3238c 189 s32_t rem_len; /* remaining length */
lorcansmith 0:2a53a4c3238c 190 LWIP_DEBUGF(PBUF_DEBUG | LWIP_DBG_TRACE, ("pbuf_alloc(length=%"U16_F")\n", length));
lorcansmith 0:2a53a4c3238c 191
lorcansmith 0:2a53a4c3238c 192 /* determine header offset */
lorcansmith 0:2a53a4c3238c 193 offset = 0;
lorcansmith 0:2a53a4c3238c 194 switch (layer) {
lorcansmith 0:2a53a4c3238c 195 case PBUF_TRANSPORT:
lorcansmith 0:2a53a4c3238c 196 /* add room for transport (often TCP) layer header */
lorcansmith 0:2a53a4c3238c 197 offset += PBUF_TRANSPORT_HLEN;
lorcansmith 0:2a53a4c3238c 198 /* FALLTHROUGH */
lorcansmith 0:2a53a4c3238c 199 case PBUF_IP:
lorcansmith 0:2a53a4c3238c 200 /* add room for IP layer header */
lorcansmith 0:2a53a4c3238c 201 offset += PBUF_IP_HLEN;
lorcansmith 0:2a53a4c3238c 202 /* FALLTHROUGH */
lorcansmith 0:2a53a4c3238c 203 case PBUF_LINK:
lorcansmith 0:2a53a4c3238c 204 /* add room for link layer header */
lorcansmith 0:2a53a4c3238c 205 offset += PBUF_LINK_HLEN;
lorcansmith 0:2a53a4c3238c 206 break;
lorcansmith 0:2a53a4c3238c 207 case PBUF_RAW:
lorcansmith 0:2a53a4c3238c 208 break;
lorcansmith 0:2a53a4c3238c 209 default:
lorcansmith 0:2a53a4c3238c 210 LWIP_ASSERT("pbuf_alloc: bad pbuf layer", 0);
lorcansmith 0:2a53a4c3238c 211 return NULL;
lorcansmith 0:2a53a4c3238c 212 }
lorcansmith 0:2a53a4c3238c 213
lorcansmith 0:2a53a4c3238c 214 switch (type) {
lorcansmith 0:2a53a4c3238c 215 case PBUF_POOL:
lorcansmith 0:2a53a4c3238c 216 /* allocate head of pbuf chain into p */
lorcansmith 0:2a53a4c3238c 217 p = (struct pbuf *)memp_malloc(MEMP_PBUF_POOL);
lorcansmith 0:2a53a4c3238c 218 LWIP_DEBUGF(PBUF_DEBUG | LWIP_DBG_TRACE, ("pbuf_alloc: allocated pbuf %p\n", (void *)p));
lorcansmith 0:2a53a4c3238c 219 if (p == NULL) {
lorcansmith 0:2a53a4c3238c 220 PBUF_POOL_IS_EMPTY();
lorcansmith 0:2a53a4c3238c 221 return NULL;
lorcansmith 0:2a53a4c3238c 222 }
lorcansmith 0:2a53a4c3238c 223 p->type = type;
lorcansmith 0:2a53a4c3238c 224 p->next = NULL;
lorcansmith 0:2a53a4c3238c 225
lorcansmith 0:2a53a4c3238c 226 /* make the payload pointer point 'offset' bytes into pbuf data memory */
lorcansmith 0:2a53a4c3238c 227 p->payload = LWIP_MEM_ALIGN((void *)((u8_t *)p + (SIZEOF_STRUCT_PBUF + offset)));
lorcansmith 0:2a53a4c3238c 228 LWIP_ASSERT("pbuf_alloc: pbuf p->payload properly aligned",
lorcansmith 0:2a53a4c3238c 229 ((mem_ptr_t)p->payload % MEM_ALIGNMENT) == 0);
lorcansmith 0:2a53a4c3238c 230 /* the total length of the pbuf chain is the requested size */
lorcansmith 0:2a53a4c3238c 231 p->tot_len = length;
lorcansmith 0:2a53a4c3238c 232 /* set the length of the first pbuf in the chain */
lorcansmith 0:2a53a4c3238c 233 p->len = LWIP_MIN(length, PBUF_POOL_BUFSIZE_ALIGNED - LWIP_MEM_ALIGN_SIZE(offset));
lorcansmith 0:2a53a4c3238c 234 LWIP_ASSERT("check p->payload + p->len does not overflow pbuf",
lorcansmith 0:2a53a4c3238c 235 ((u8_t*)p->payload + p->len <=
lorcansmith 0:2a53a4c3238c 236 (u8_t*)p + SIZEOF_STRUCT_PBUF + PBUF_POOL_BUFSIZE_ALIGNED));
lorcansmith 0:2a53a4c3238c 237 LWIP_ASSERT("PBUF_POOL_BUFSIZE must be bigger than MEM_ALIGNMENT",
lorcansmith 0:2a53a4c3238c 238 (PBUF_POOL_BUFSIZE_ALIGNED - LWIP_MEM_ALIGN_SIZE(offset)) > 0 );
lorcansmith 0:2a53a4c3238c 239 /* set reference count (needed here in case we fail) */
lorcansmith 0:2a53a4c3238c 240 p->ref = 1;
lorcansmith 0:2a53a4c3238c 241
lorcansmith 0:2a53a4c3238c 242 /* now allocate the tail of the pbuf chain */
lorcansmith 0:2a53a4c3238c 243
lorcansmith 0:2a53a4c3238c 244 /* remember first pbuf for linkage in next iteration */
lorcansmith 0:2a53a4c3238c 245 r = p;
lorcansmith 0:2a53a4c3238c 246 /* remaining length to be allocated */
lorcansmith 0:2a53a4c3238c 247 rem_len = length - p->len;
lorcansmith 0:2a53a4c3238c 248 /* any remaining pbufs to be allocated? */
lorcansmith 0:2a53a4c3238c 249 while (rem_len > 0) {
lorcansmith 0:2a53a4c3238c 250 q = (struct pbuf *)memp_malloc(MEMP_PBUF_POOL);
lorcansmith 0:2a53a4c3238c 251 if (q == NULL) {
lorcansmith 0:2a53a4c3238c 252 PBUF_POOL_IS_EMPTY();
lorcansmith 0:2a53a4c3238c 253 /* free chain so far allocated */
lorcansmith 0:2a53a4c3238c 254 pbuf_free(p);
lorcansmith 0:2a53a4c3238c 255 /* bail out unsuccesfully */
lorcansmith 0:2a53a4c3238c 256 return NULL;
lorcansmith 0:2a53a4c3238c 257 }
lorcansmith 0:2a53a4c3238c 258 q->type = type;
lorcansmith 0:2a53a4c3238c 259 q->flags = 0;
lorcansmith 0:2a53a4c3238c 260 q->next = NULL;
lorcansmith 0:2a53a4c3238c 261 /* make previous pbuf point to this pbuf */
lorcansmith 0:2a53a4c3238c 262 r->next = q;
lorcansmith 0:2a53a4c3238c 263 /* set total length of this pbuf and next in chain */
lorcansmith 0:2a53a4c3238c 264 LWIP_ASSERT("rem_len < max_u16_t", rem_len < 0xffff);
lorcansmith 0:2a53a4c3238c 265 q->tot_len = (u16_t)rem_len;
lorcansmith 0:2a53a4c3238c 266 /* this pbuf length is pool size, unless smaller sized tail */
lorcansmith 0:2a53a4c3238c 267 q->len = LWIP_MIN((u16_t)rem_len, PBUF_POOL_BUFSIZE_ALIGNED);
lorcansmith 0:2a53a4c3238c 268 q->payload = (void *)((u8_t *)q + SIZEOF_STRUCT_PBUF);
lorcansmith 0:2a53a4c3238c 269 LWIP_ASSERT("pbuf_alloc: pbuf q->payload properly aligned",
lorcansmith 0:2a53a4c3238c 270 ((mem_ptr_t)q->payload % MEM_ALIGNMENT) == 0);
lorcansmith 0:2a53a4c3238c 271 LWIP_ASSERT("check p->payload + p->len does not overflow pbuf",
lorcansmith 0:2a53a4c3238c 272 ((u8_t*)p->payload + p->len <=
lorcansmith 0:2a53a4c3238c 273 (u8_t*)p + SIZEOF_STRUCT_PBUF + PBUF_POOL_BUFSIZE_ALIGNED));
lorcansmith 0:2a53a4c3238c 274 q->ref = 1;
lorcansmith 0:2a53a4c3238c 275 /* calculate remaining length to be allocated */
lorcansmith 0:2a53a4c3238c 276 rem_len -= q->len;
lorcansmith 0:2a53a4c3238c 277 /* remember this pbuf for linkage in next iteration */
lorcansmith 0:2a53a4c3238c 278 r = q;
lorcansmith 0:2a53a4c3238c 279 }
lorcansmith 0:2a53a4c3238c 280 /* end of chain */
lorcansmith 0:2a53a4c3238c 281 /*r->next = NULL;*/
lorcansmith 0:2a53a4c3238c 282
lorcansmith 0:2a53a4c3238c 283 break;
lorcansmith 0:2a53a4c3238c 284 case PBUF_RAM:
lorcansmith 0:2a53a4c3238c 285 /* If pbuf is to be allocated in RAM, allocate memory for it. */
lorcansmith 0:2a53a4c3238c 286 p = (struct pbuf*)mem_malloc(LWIP_MEM_ALIGN_SIZE(SIZEOF_STRUCT_PBUF + offset) + LWIP_MEM_ALIGN_SIZE(length));
lorcansmith 0:2a53a4c3238c 287 if (p == NULL) {
lorcansmith 0:2a53a4c3238c 288 return NULL;
lorcansmith 0:2a53a4c3238c 289 }
lorcansmith 0:2a53a4c3238c 290 /* Set up internal structure of the pbuf. */
lorcansmith 0:2a53a4c3238c 291 p->payload = LWIP_MEM_ALIGN((void *)((u8_t *)p + SIZEOF_STRUCT_PBUF + offset));
lorcansmith 0:2a53a4c3238c 292 p->len = p->tot_len = length;
lorcansmith 0:2a53a4c3238c 293 p->next = NULL;
lorcansmith 0:2a53a4c3238c 294 p->type = type;
lorcansmith 0:2a53a4c3238c 295
lorcansmith 0:2a53a4c3238c 296 LWIP_ASSERT("pbuf_alloc: pbuf->payload properly aligned",
lorcansmith 0:2a53a4c3238c 297 ((mem_ptr_t)p->payload % MEM_ALIGNMENT) == 0);
lorcansmith 0:2a53a4c3238c 298 break;
lorcansmith 0:2a53a4c3238c 299 /* pbuf references existing (non-volatile static constant) ROM payload? */
lorcansmith 0:2a53a4c3238c 300 case PBUF_ROM:
lorcansmith 0:2a53a4c3238c 301 /* pbuf references existing (externally allocated) RAM payload? */
lorcansmith 0:2a53a4c3238c 302 case PBUF_REF:
lorcansmith 0:2a53a4c3238c 303 /* only allocate memory for the pbuf structure */
lorcansmith 0:2a53a4c3238c 304 p = (struct pbuf *)memp_malloc(MEMP_PBUF);
lorcansmith 0:2a53a4c3238c 305 if (p == NULL) {
lorcansmith 0:2a53a4c3238c 306 LWIP_DEBUGF(PBUF_DEBUG | LWIP_DBG_LEVEL_SERIOUS,
lorcansmith 0:2a53a4c3238c 307 ("pbuf_alloc: Could not allocate MEMP_PBUF for PBUF_%s.\n",
lorcansmith 0:2a53a4c3238c 308 (type == PBUF_ROM) ? "ROM" : "REF"));
lorcansmith 0:2a53a4c3238c 309 return NULL;
lorcansmith 0:2a53a4c3238c 310 }
lorcansmith 0:2a53a4c3238c 311 /* caller must set this field properly, afterwards */
lorcansmith 0:2a53a4c3238c 312 p->payload = NULL;
lorcansmith 0:2a53a4c3238c 313 p->len = p->tot_len = length;
lorcansmith 0:2a53a4c3238c 314 p->next = NULL;
lorcansmith 0:2a53a4c3238c 315 p->type = type;
lorcansmith 0:2a53a4c3238c 316 break;
lorcansmith 0:2a53a4c3238c 317 default:
lorcansmith 0:2a53a4c3238c 318 LWIP_ASSERT("pbuf_alloc: erroneous type", 0);
lorcansmith 0:2a53a4c3238c 319 return NULL;
lorcansmith 0:2a53a4c3238c 320 }
lorcansmith 0:2a53a4c3238c 321 /* set reference count */
lorcansmith 0:2a53a4c3238c 322 p->ref = 1;
lorcansmith 0:2a53a4c3238c 323 /* set flags */
lorcansmith 0:2a53a4c3238c 324 p->flags = 0;
lorcansmith 0:2a53a4c3238c 325 LWIP_DEBUGF(PBUF_DEBUG | LWIP_DBG_TRACE, ("pbuf_alloc(length=%"U16_F") == %p\n", length, (void *)p));
lorcansmith 0:2a53a4c3238c 326 return p;
lorcansmith 0:2a53a4c3238c 327 }
lorcansmith 0:2a53a4c3238c 328
lorcansmith 0:2a53a4c3238c 329 #if LWIP_SUPPORT_CUSTOM_PBUF
lorcansmith 0:2a53a4c3238c 330 /** Initialize a custom pbuf (already allocated).
lorcansmith 0:2a53a4c3238c 331 *
lorcansmith 0:2a53a4c3238c 332 * @param layer flag to define header size
lorcansmith 0:2a53a4c3238c 333 * @param length size of the pbuf's payload
lorcansmith 0:2a53a4c3238c 334 * @param type type of the pbuf (only used to treat the pbuf accordingly, as
lorcansmith 0:2a53a4c3238c 335 * this function allocates no memory)
lorcansmith 0:2a53a4c3238c 336 * @param p pointer to the custom pbuf to initialize (already allocated)
lorcansmith 0:2a53a4c3238c 337 * @param payload_mem pointer to the buffer that is used for payload and headers,
lorcansmith 0:2a53a4c3238c 338 * must be at least big enough to hold 'length' plus the header size,
lorcansmith 0:2a53a4c3238c 339 * may be NULL if set later
lorcansmith 0:2a53a4c3238c 340 * @param payload_mem_len the size of the 'payload_mem' buffer, must be at least
lorcansmith 0:2a53a4c3238c 341 * big enough to hold 'length' plus the header size
lorcansmith 0:2a53a4c3238c 342 */
lorcansmith 0:2a53a4c3238c 343 struct pbuf*
lorcansmith 0:2a53a4c3238c 344 pbuf_alloced_custom(pbuf_layer l, u16_t length, pbuf_type type, struct pbuf_custom *p,
lorcansmith 0:2a53a4c3238c 345 void *payload_mem, u16_t payload_mem_len)
lorcansmith 0:2a53a4c3238c 346 {
lorcansmith 0:2a53a4c3238c 347 u16_t offset;
lorcansmith 0:2a53a4c3238c 348 LWIP_DEBUGF(PBUF_DEBUG | LWIP_DBG_TRACE, ("pbuf_alloced_custom(length=%"U16_F")\n", length));
lorcansmith 0:2a53a4c3238c 349
lorcansmith 0:2a53a4c3238c 350 /* determine header offset */
lorcansmith 0:2a53a4c3238c 351 offset = 0;
lorcansmith 0:2a53a4c3238c 352 switch (l) {
lorcansmith 0:2a53a4c3238c 353 case PBUF_TRANSPORT:
lorcansmith 0:2a53a4c3238c 354 /* add room for transport (often TCP) layer header */
lorcansmith 0:2a53a4c3238c 355 offset += PBUF_TRANSPORT_HLEN;
lorcansmith 0:2a53a4c3238c 356 /* FALLTHROUGH */
lorcansmith 0:2a53a4c3238c 357 case PBUF_IP:
lorcansmith 0:2a53a4c3238c 358 /* add room for IP layer header */
lorcansmith 0:2a53a4c3238c 359 offset += PBUF_IP_HLEN;
lorcansmith 0:2a53a4c3238c 360 /* FALLTHROUGH */
lorcansmith 0:2a53a4c3238c 361 case PBUF_LINK:
lorcansmith 0:2a53a4c3238c 362 /* add room for link layer header */
lorcansmith 0:2a53a4c3238c 363 offset += PBUF_LINK_HLEN;
lorcansmith 0:2a53a4c3238c 364 break;
lorcansmith 0:2a53a4c3238c 365 case PBUF_RAW:
lorcansmith 0:2a53a4c3238c 366 break;
lorcansmith 0:2a53a4c3238c 367 default:
lorcansmith 0:2a53a4c3238c 368 LWIP_ASSERT("pbuf_alloced_custom: bad pbuf layer", 0);
lorcansmith 0:2a53a4c3238c 369 return NULL;
lorcansmith 0:2a53a4c3238c 370 }
lorcansmith 0:2a53a4c3238c 371
lorcansmith 0:2a53a4c3238c 372 if (LWIP_MEM_ALIGN_SIZE(offset) + length < payload_mem_len) {
lorcansmith 0:2a53a4c3238c 373 LWIP_DEBUGF(PBUF_DEBUG | LWIP_DBG_LEVEL_WARNING, ("pbuf_alloced_custom(length=%"U16_F") buffer too short\n", length));
lorcansmith 0:2a53a4c3238c 374 return NULL;
lorcansmith 0:2a53a4c3238c 375 }
lorcansmith 0:2a53a4c3238c 376
lorcansmith 0:2a53a4c3238c 377 p->pbuf.next = NULL;
lorcansmith 0:2a53a4c3238c 378 if (payload_mem != NULL) {
lorcansmith 0:2a53a4c3238c 379 p->pbuf.payload = LWIP_MEM_ALIGN((void *)((u8_t *)payload_mem + offset));
lorcansmith 0:2a53a4c3238c 380 } else {
lorcansmith 0:2a53a4c3238c 381 p->pbuf.payload = NULL;
lorcansmith 0:2a53a4c3238c 382 }
lorcansmith 0:2a53a4c3238c 383 p->pbuf.flags = PBUF_FLAG_IS_CUSTOM;
lorcansmith 0:2a53a4c3238c 384 p->pbuf.len = p->pbuf.tot_len = length;
lorcansmith 0:2a53a4c3238c 385 p->pbuf.type = type;
lorcansmith 0:2a53a4c3238c 386 p->pbuf.ref = 1;
lorcansmith 0:2a53a4c3238c 387 return &p->pbuf;
lorcansmith 0:2a53a4c3238c 388 }
lorcansmith 0:2a53a4c3238c 389 #endif /* LWIP_SUPPORT_CUSTOM_PBUF */
lorcansmith 0:2a53a4c3238c 390
lorcansmith 0:2a53a4c3238c 391 /**
lorcansmith 0:2a53a4c3238c 392 * Shrink a pbuf chain to a desired length.
lorcansmith 0:2a53a4c3238c 393 *
lorcansmith 0:2a53a4c3238c 394 * @param p pbuf to shrink.
lorcansmith 0:2a53a4c3238c 395 * @param new_len desired new length of pbuf chain
lorcansmith 0:2a53a4c3238c 396 *
lorcansmith 0:2a53a4c3238c 397 * Depending on the desired length, the first few pbufs in a chain might
lorcansmith 0:2a53a4c3238c 398 * be skipped and left unchanged. The new last pbuf in the chain will be
lorcansmith 0:2a53a4c3238c 399 * resized, and any remaining pbufs will be freed.
lorcansmith 0:2a53a4c3238c 400 *
lorcansmith 0:2a53a4c3238c 401 * @note If the pbuf is ROM/REF, only the ->tot_len and ->len fields are adjusted.
lorcansmith 0:2a53a4c3238c 402 * @note May not be called on a packet queue.
lorcansmith 0:2a53a4c3238c 403 *
lorcansmith 0:2a53a4c3238c 404 * @note Despite its name, pbuf_realloc cannot grow the size of a pbuf (chain).
lorcansmith 0:2a53a4c3238c 405 */
lorcansmith 0:2a53a4c3238c 406 void
lorcansmith 0:2a53a4c3238c 407 pbuf_realloc(struct pbuf *p, u16_t new_len)
lorcansmith 0:2a53a4c3238c 408 {
lorcansmith 0:2a53a4c3238c 409 struct pbuf *q;
lorcansmith 0:2a53a4c3238c 410 u16_t rem_len; /* remaining length */
lorcansmith 0:2a53a4c3238c 411 s32_t grow;
lorcansmith 0:2a53a4c3238c 412
lorcansmith 0:2a53a4c3238c 413 LWIP_ASSERT("pbuf_realloc: p != NULL", p != NULL);
lorcansmith 0:2a53a4c3238c 414 LWIP_ASSERT("pbuf_realloc: sane p->type", p->type == PBUF_POOL ||
lorcansmith 0:2a53a4c3238c 415 p->type == PBUF_ROM ||
lorcansmith 0:2a53a4c3238c 416 p->type == PBUF_RAM ||
lorcansmith 0:2a53a4c3238c 417 p->type == PBUF_REF);
lorcansmith 0:2a53a4c3238c 418
lorcansmith 0:2a53a4c3238c 419 /* desired length larger than current length? */
lorcansmith 0:2a53a4c3238c 420 if (new_len >= p->tot_len) {
lorcansmith 0:2a53a4c3238c 421 /* enlarging not yet supported */
lorcansmith 0:2a53a4c3238c 422 return;
lorcansmith 0:2a53a4c3238c 423 }
lorcansmith 0:2a53a4c3238c 424
lorcansmith 0:2a53a4c3238c 425 /* the pbuf chain grows by (new_len - p->tot_len) bytes
lorcansmith 0:2a53a4c3238c 426 * (which may be negative in case of shrinking) */
lorcansmith 0:2a53a4c3238c 427 grow = new_len - p->tot_len;
lorcansmith 0:2a53a4c3238c 428
lorcansmith 0:2a53a4c3238c 429 /* first, step over any pbufs that should remain in the chain */
lorcansmith 0:2a53a4c3238c 430 rem_len = new_len;
lorcansmith 0:2a53a4c3238c 431 q = p;
lorcansmith 0:2a53a4c3238c 432 /* should this pbuf be kept? */
lorcansmith 0:2a53a4c3238c 433 while (rem_len > q->len) {
lorcansmith 0:2a53a4c3238c 434 /* decrease remaining length by pbuf length */
lorcansmith 0:2a53a4c3238c 435 rem_len -= q->len;
lorcansmith 0:2a53a4c3238c 436 /* decrease total length indicator */
lorcansmith 0:2a53a4c3238c 437 LWIP_ASSERT("grow < max_u16_t", grow < 0xffff);
lorcansmith 0:2a53a4c3238c 438 q->tot_len += (u16_t)grow;
lorcansmith 0:2a53a4c3238c 439 /* proceed to next pbuf in chain */
lorcansmith 0:2a53a4c3238c 440 q = q->next;
lorcansmith 0:2a53a4c3238c 441 LWIP_ASSERT("pbuf_realloc: q != NULL", q != NULL);
lorcansmith 0:2a53a4c3238c 442 }
lorcansmith 0:2a53a4c3238c 443 /* we have now reached the new last pbuf (in q) */
lorcansmith 0:2a53a4c3238c 444 /* rem_len == desired length for pbuf q */
lorcansmith 0:2a53a4c3238c 445
lorcansmith 0:2a53a4c3238c 446 /* shrink allocated memory for PBUF_RAM */
lorcansmith 0:2a53a4c3238c 447 /* (other types merely adjust their length fields */
lorcansmith 0:2a53a4c3238c 448 if ((q->type == PBUF_RAM) && (rem_len != q->len)) {
lorcansmith 0:2a53a4c3238c 449 /* reallocate and adjust the length of the pbuf that will be split */
lorcansmith 0:2a53a4c3238c 450 q = (struct pbuf *)mem_trim(q, (u16_t)((u8_t *)q->payload - (u8_t *)q) + rem_len);
lorcansmith 0:2a53a4c3238c 451 LWIP_ASSERT("mem_trim returned q == NULL", q != NULL);
lorcansmith 0:2a53a4c3238c 452 }
lorcansmith 0:2a53a4c3238c 453 /* adjust length fields for new last pbuf */
lorcansmith 0:2a53a4c3238c 454 q->len = rem_len;
lorcansmith 0:2a53a4c3238c 455 q->tot_len = q->len;
lorcansmith 0:2a53a4c3238c 456
lorcansmith 0:2a53a4c3238c 457 /* any remaining pbufs in chain? */
lorcansmith 0:2a53a4c3238c 458 if (q->next != NULL) {
lorcansmith 0:2a53a4c3238c 459 /* free remaining pbufs in chain */
lorcansmith 0:2a53a4c3238c 460 pbuf_free(q->next);
lorcansmith 0:2a53a4c3238c 461 }
lorcansmith 0:2a53a4c3238c 462 /* q is last packet in chain */
lorcansmith 0:2a53a4c3238c 463 q->next = NULL;
lorcansmith 0:2a53a4c3238c 464
lorcansmith 0:2a53a4c3238c 465 }
lorcansmith 0:2a53a4c3238c 466
lorcansmith 0:2a53a4c3238c 467 /**
lorcansmith 0:2a53a4c3238c 468 * Adjusts the payload pointer to hide or reveal headers in the payload.
lorcansmith 0:2a53a4c3238c 469 *
lorcansmith 0:2a53a4c3238c 470 * Adjusts the ->payload pointer so that space for a header
lorcansmith 0:2a53a4c3238c 471 * (dis)appears in the pbuf payload.
lorcansmith 0:2a53a4c3238c 472 *
lorcansmith 0:2a53a4c3238c 473 * The ->payload, ->tot_len and ->len fields are adjusted.
lorcansmith 0:2a53a4c3238c 474 *
lorcansmith 0:2a53a4c3238c 475 * @param p pbuf to change the header size.
lorcansmith 0:2a53a4c3238c 476 * @param header_size_increment Number of bytes to increment header size which
lorcansmith 0:2a53a4c3238c 477 * increases the size of the pbuf. New space is on the front.
lorcansmith 0:2a53a4c3238c 478 * (Using a negative value decreases the header size.)
lorcansmith 0:2a53a4c3238c 479 * If hdr_size_inc is 0, this function does nothing and returns succesful.
lorcansmith 0:2a53a4c3238c 480 *
lorcansmith 0:2a53a4c3238c 481 * PBUF_ROM and PBUF_REF type buffers cannot have their sizes increased, so
lorcansmith 0:2a53a4c3238c 482 * the call will fail. A check is made that the increase in header size does
lorcansmith 0:2a53a4c3238c 483 * not move the payload pointer in front of the start of the buffer.
lorcansmith 0:2a53a4c3238c 484 * @return non-zero on failure, zero on success.
lorcansmith 0:2a53a4c3238c 485 *
lorcansmith 0:2a53a4c3238c 486 */
lorcansmith 0:2a53a4c3238c 487 u8_t
lorcansmith 0:2a53a4c3238c 488 pbuf_header(struct pbuf *p, s16_t header_size_increment)
lorcansmith 0:2a53a4c3238c 489 {
lorcansmith 0:2a53a4c3238c 490 u16_t type;
lorcansmith 0:2a53a4c3238c 491 void *payload;
lorcansmith 0:2a53a4c3238c 492 u16_t increment_magnitude;
lorcansmith 0:2a53a4c3238c 493
lorcansmith 0:2a53a4c3238c 494 LWIP_ASSERT("p != NULL", p != NULL);
lorcansmith 0:2a53a4c3238c 495 if ((header_size_increment == 0) || (p == NULL)) {
lorcansmith 0:2a53a4c3238c 496 return 0;
lorcansmith 0:2a53a4c3238c 497 }
lorcansmith 0:2a53a4c3238c 498
lorcansmith 0:2a53a4c3238c 499 if (header_size_increment < 0){
lorcansmith 0:2a53a4c3238c 500 increment_magnitude = -header_size_increment;
lorcansmith 0:2a53a4c3238c 501 /* Check that we aren't going to move off the end of the pbuf */
lorcansmith 0:2a53a4c3238c 502 LWIP_ERROR("increment_magnitude <= p->len", (increment_magnitude <= p->len), return 1;);
lorcansmith 0:2a53a4c3238c 503 } else {
lorcansmith 0:2a53a4c3238c 504 increment_magnitude = header_size_increment;
lorcansmith 0:2a53a4c3238c 505 #if 0
lorcansmith 0:2a53a4c3238c 506 /* Can't assert these as some callers speculatively call
lorcansmith 0:2a53a4c3238c 507 pbuf_header() to see if it's OK. Will return 1 below instead. */
lorcansmith 0:2a53a4c3238c 508 /* Check that we've got the correct type of pbuf to work with */
lorcansmith 0:2a53a4c3238c 509 LWIP_ASSERT("p->type == PBUF_RAM || p->type == PBUF_POOL",
lorcansmith 0:2a53a4c3238c 510 p->type == PBUF_RAM || p->type == PBUF_POOL);
lorcansmith 0:2a53a4c3238c 511 /* Check that we aren't going to move off the beginning of the pbuf */
lorcansmith 0:2a53a4c3238c 512 LWIP_ASSERT("p->payload - increment_magnitude >= p + SIZEOF_STRUCT_PBUF",
lorcansmith 0:2a53a4c3238c 513 (u8_t *)p->payload - increment_magnitude >= (u8_t *)p + SIZEOF_STRUCT_PBUF);
lorcansmith 0:2a53a4c3238c 514 #endif
lorcansmith 0:2a53a4c3238c 515 }
lorcansmith 0:2a53a4c3238c 516
lorcansmith 0:2a53a4c3238c 517 type = p->type;
lorcansmith 0:2a53a4c3238c 518 /* remember current payload pointer */
lorcansmith 0:2a53a4c3238c 519 payload = p->payload;
lorcansmith 0:2a53a4c3238c 520
lorcansmith 0:2a53a4c3238c 521 /* pbuf types containing payloads? */
lorcansmith 0:2a53a4c3238c 522 if (type == PBUF_RAM || type == PBUF_POOL) {
lorcansmith 0:2a53a4c3238c 523 /* set new payload pointer */
lorcansmith 0:2a53a4c3238c 524 p->payload = (u8_t *)p->payload - header_size_increment;
lorcansmith 0:2a53a4c3238c 525 /* boundary check fails? */
lorcansmith 0:2a53a4c3238c 526 if ((u8_t *)p->payload < (u8_t *)p + SIZEOF_STRUCT_PBUF) {
lorcansmith 0:2a53a4c3238c 527 LWIP_DEBUGF( PBUF_DEBUG | LWIP_DBG_LEVEL_SERIOUS,
lorcansmith 0:2a53a4c3238c 528 ("pbuf_header: failed as %p < %p (not enough space for new header size)\n",
lorcansmith 0:2a53a4c3238c 529 (void *)p->payload, (void *)(p + 1)));
lorcansmith 0:2a53a4c3238c 530 /* restore old payload pointer */
lorcansmith 0:2a53a4c3238c 531 p->payload = payload;
lorcansmith 0:2a53a4c3238c 532 /* bail out unsuccesfully */
lorcansmith 0:2a53a4c3238c 533 return 1;
lorcansmith 0:2a53a4c3238c 534 }
lorcansmith 0:2a53a4c3238c 535 /* pbuf types refering to external payloads? */
lorcansmith 0:2a53a4c3238c 536 } else if (type == PBUF_REF || type == PBUF_ROM) {
lorcansmith 0:2a53a4c3238c 537 /* hide a header in the payload? */
lorcansmith 0:2a53a4c3238c 538 if ((header_size_increment < 0) && (increment_magnitude <= p->len)) {
lorcansmith 0:2a53a4c3238c 539 /* increase payload pointer */
lorcansmith 0:2a53a4c3238c 540 p->payload = (u8_t *)p->payload - header_size_increment;
lorcansmith 0:2a53a4c3238c 541 } else {
lorcansmith 0:2a53a4c3238c 542 /* cannot expand payload to front (yet!)
lorcansmith 0:2a53a4c3238c 543 * bail out unsuccesfully */
lorcansmith 0:2a53a4c3238c 544 return 1;
lorcansmith 0:2a53a4c3238c 545 }
lorcansmith 0:2a53a4c3238c 546 } else {
lorcansmith 0:2a53a4c3238c 547 /* Unknown type */
lorcansmith 0:2a53a4c3238c 548 LWIP_ASSERT("bad pbuf type", 0);
lorcansmith 0:2a53a4c3238c 549 return 1;
lorcansmith 0:2a53a4c3238c 550 }
lorcansmith 0:2a53a4c3238c 551 /* modify pbuf length fields */
lorcansmith 0:2a53a4c3238c 552 p->len += header_size_increment;
lorcansmith 0:2a53a4c3238c 553 p->tot_len += header_size_increment;
lorcansmith 0:2a53a4c3238c 554
lorcansmith 0:2a53a4c3238c 555 LWIP_DEBUGF(PBUF_DEBUG | LWIP_DBG_TRACE, ("pbuf_header: old %p new %p (%"S16_F")\n",
lorcansmith 0:2a53a4c3238c 556 (void *)payload, (void *)p->payload, header_size_increment));
lorcansmith 0:2a53a4c3238c 557 //printf("pbuf_header: p->tot_len %d (%"S16_F")\r\n", p->tot_len, header_size_increment);
lorcansmith 0:2a53a4c3238c 558
lorcansmith 0:2a53a4c3238c 559 return 0;
lorcansmith 0:2a53a4c3238c 560 }
lorcansmith 0:2a53a4c3238c 561
lorcansmith 0:2a53a4c3238c 562 /**
lorcansmith 0:2a53a4c3238c 563 * Dereference a pbuf chain or queue and deallocate any no-longer-used
lorcansmith 0:2a53a4c3238c 564 * pbufs at the head of this chain or queue.
lorcansmith 0:2a53a4c3238c 565 *
lorcansmith 0:2a53a4c3238c 566 * Decrements the pbuf reference count. If it reaches zero, the pbuf is
lorcansmith 0:2a53a4c3238c 567 * deallocated.
lorcansmith 0:2a53a4c3238c 568 *
lorcansmith 0:2a53a4c3238c 569 * For a pbuf chain, this is repeated for each pbuf in the chain,
lorcansmith 0:2a53a4c3238c 570 * up to the first pbuf which has a non-zero reference count after
lorcansmith 0:2a53a4c3238c 571 * decrementing. So, when all reference counts are one, the whole
lorcansmith 0:2a53a4c3238c 572 * chain is free'd.
lorcansmith 0:2a53a4c3238c 573 *
lorcansmith 0:2a53a4c3238c 574 * @param p The pbuf (chain) to be dereferenced.
lorcansmith 0:2a53a4c3238c 575 *
lorcansmith 0:2a53a4c3238c 576 * @return the number of pbufs that were de-allocated
lorcansmith 0:2a53a4c3238c 577 * from the head of the chain.
lorcansmith 0:2a53a4c3238c 578 *
lorcansmith 0:2a53a4c3238c 579 * @note MUST NOT be called on a packet queue (Not verified to work yet).
lorcansmith 0:2a53a4c3238c 580 * @note the reference counter of a pbuf equals the number of pointers
lorcansmith 0:2a53a4c3238c 581 * that refer to the pbuf (or into the pbuf).
lorcansmith 0:2a53a4c3238c 582 *
lorcansmith 0:2a53a4c3238c 583 * @internal examples:
lorcansmith 0:2a53a4c3238c 584 *
lorcansmith 0:2a53a4c3238c 585 * Assuming existing chains a->b->c with the following reference
lorcansmith 0:2a53a4c3238c 586 * counts, calling pbuf_free(a) results in:
lorcansmith 0:2a53a4c3238c 587 *
lorcansmith 0:2a53a4c3238c 588 * 1->2->3 becomes ...1->3
lorcansmith 0:2a53a4c3238c 589 * 3->3->3 becomes 2->3->3
lorcansmith 0:2a53a4c3238c 590 * 1->1->2 becomes ......1
lorcansmith 0:2a53a4c3238c 591 * 2->1->1 becomes 1->1->1
lorcansmith 0:2a53a4c3238c 592 * 1->1->1 becomes .......
lorcansmith 0:2a53a4c3238c 593 *
lorcansmith 0:2a53a4c3238c 594 */
lorcansmith 0:2a53a4c3238c 595 u8_t
lorcansmith 0:2a53a4c3238c 596 pbuf_free(struct pbuf *p)
lorcansmith 0:2a53a4c3238c 597 {
lorcansmith 0:2a53a4c3238c 598 u16_t type;
lorcansmith 0:2a53a4c3238c 599 struct pbuf *q;
lorcansmith 0:2a53a4c3238c 600 u8_t count;
lorcansmith 0:2a53a4c3238c 601
lorcansmith 0:2a53a4c3238c 602 if (p == NULL) {
lorcansmith 0:2a53a4c3238c 603 LWIP_ASSERT("p != NULL", p != NULL);
lorcansmith 0:2a53a4c3238c 604 /* if assertions are disabled, proceed with debug output */
lorcansmith 0:2a53a4c3238c 605 LWIP_DEBUGF(PBUF_DEBUG | LWIP_DBG_LEVEL_SERIOUS,
lorcansmith 0:2a53a4c3238c 606 ("pbuf_free(p == NULL) was called.\n"));
lorcansmith 0:2a53a4c3238c 607 return 0;
lorcansmith 0:2a53a4c3238c 608 }
lorcansmith 0:2a53a4c3238c 609 LWIP_DEBUGF(PBUF_DEBUG | LWIP_DBG_TRACE, ("pbuf_free(%p)\n", (void *)p));
lorcansmith 0:2a53a4c3238c 610
lorcansmith 0:2a53a4c3238c 611 PERF_START;
lorcansmith 0:2a53a4c3238c 612
lorcansmith 0:2a53a4c3238c 613 LWIP_ASSERT("pbuf_free: sane type",
lorcansmith 0:2a53a4c3238c 614 p->type == PBUF_RAM || p->type == PBUF_ROM ||
lorcansmith 0:2a53a4c3238c 615 p->type == PBUF_REF || p->type == PBUF_POOL);
lorcansmith 0:2a53a4c3238c 616
lorcansmith 0:2a53a4c3238c 617 count = 0;
lorcansmith 0:2a53a4c3238c 618 /* de-allocate all consecutive pbufs from the head of the chain that
lorcansmith 0:2a53a4c3238c 619 * obtain a zero reference count after decrementing*/
lorcansmith 0:2a53a4c3238c 620 while (p != NULL) {
lorcansmith 0:2a53a4c3238c 621 u16_t ref;
lorcansmith 0:2a53a4c3238c 622 SYS_ARCH_DECL_PROTECT(old_level);
lorcansmith 0:2a53a4c3238c 623 /* Since decrementing ref cannot be guaranteed to be a single machine operation
lorcansmith 0:2a53a4c3238c 624 * we must protect it. We put the new ref into a local variable to prevent
lorcansmith 0:2a53a4c3238c 625 * further protection. */
lorcansmith 0:2a53a4c3238c 626 SYS_ARCH_PROTECT(old_level);
lorcansmith 0:2a53a4c3238c 627 /* all pbufs in a chain are referenced at least once */
lorcansmith 0:2a53a4c3238c 628 LWIP_ASSERT("pbuf_free: p->ref > 0", p->ref > 0);
lorcansmith 0:2a53a4c3238c 629 /* decrease reference count (number of pointers to pbuf) */
lorcansmith 0:2a53a4c3238c 630 ref = --(p->ref);
lorcansmith 0:2a53a4c3238c 631 SYS_ARCH_UNPROTECT(old_level);
lorcansmith 0:2a53a4c3238c 632 /* this pbuf is no longer referenced to? */
lorcansmith 0:2a53a4c3238c 633 if (ref == 0) {
lorcansmith 0:2a53a4c3238c 634 /* remember next pbuf in chain for next iteration */
lorcansmith 0:2a53a4c3238c 635 q = p->next;
lorcansmith 0:2a53a4c3238c 636 LWIP_DEBUGF( PBUF_DEBUG | LWIP_DBG_TRACE, ("pbuf_free: deallocating %p\n", (void *)p));
lorcansmith 0:2a53a4c3238c 637 type = p->type;
lorcansmith 0:2a53a4c3238c 638 #if LWIP_SUPPORT_CUSTOM_PBUF
lorcansmith 0:2a53a4c3238c 639 /* is this a custom pbuf? */
lorcansmith 0:2a53a4c3238c 640 if ((p->flags & PBUF_FLAG_IS_CUSTOM) != 0) {
lorcansmith 0:2a53a4c3238c 641 struct pbuf_custom *pc = (struct pbuf_custom*)p;
lorcansmith 0:2a53a4c3238c 642 LWIP_ASSERT("pc->custom_free_function != NULL", pc->custom_free_function != NULL);
lorcansmith 0:2a53a4c3238c 643 pc->custom_free_function(p);
lorcansmith 0:2a53a4c3238c 644 } else
lorcansmith 0:2a53a4c3238c 645 #endif /* LWIP_SUPPORT_CUSTOM_PBUF */
lorcansmith 0:2a53a4c3238c 646 {
lorcansmith 0:2a53a4c3238c 647 /* is this a pbuf from the pool? */
lorcansmith 0:2a53a4c3238c 648 if (type == PBUF_POOL) {
lorcansmith 0:2a53a4c3238c 649 memp_free(MEMP_PBUF_POOL, p);
lorcansmith 0:2a53a4c3238c 650 /* is this a ROM or RAM referencing pbuf? */
lorcansmith 0:2a53a4c3238c 651 } else if (type == PBUF_ROM || type == PBUF_REF) {
lorcansmith 0:2a53a4c3238c 652 memp_free(MEMP_PBUF, p);
lorcansmith 0:2a53a4c3238c 653 /* type == PBUF_RAM */
lorcansmith 0:2a53a4c3238c 654 } else {
lorcansmith 0:2a53a4c3238c 655 mem_free(p);
lorcansmith 0:2a53a4c3238c 656 }
lorcansmith 0:2a53a4c3238c 657 }
lorcansmith 0:2a53a4c3238c 658 count++;
lorcansmith 0:2a53a4c3238c 659 /* proceed to next pbuf */
lorcansmith 0:2a53a4c3238c 660 p = q;
lorcansmith 0:2a53a4c3238c 661 /* p->ref > 0, this pbuf is still referenced to */
lorcansmith 0:2a53a4c3238c 662 /* (and so the remaining pbufs in chain as well) */
lorcansmith 0:2a53a4c3238c 663 } else {
lorcansmith 0:2a53a4c3238c 664 LWIP_DEBUGF( PBUF_DEBUG | LWIP_DBG_TRACE, ("pbuf_free: %p has ref %"U16_F", ending here.\n", (void *)p, ref));
lorcansmith 0:2a53a4c3238c 665 /* stop walking through the chain */
lorcansmith 0:2a53a4c3238c 666 p = NULL;
lorcansmith 0:2a53a4c3238c 667 }
lorcansmith 0:2a53a4c3238c 668 }
lorcansmith 0:2a53a4c3238c 669 PERF_STOP("pbuf_free");
lorcansmith 0:2a53a4c3238c 670 /* return number of de-allocated pbufs */
lorcansmith 0:2a53a4c3238c 671 return count;
lorcansmith 0:2a53a4c3238c 672 }
lorcansmith 0:2a53a4c3238c 673
lorcansmith 0:2a53a4c3238c 674 /**
lorcansmith 0:2a53a4c3238c 675 * Count number of pbufs in a chain
lorcansmith 0:2a53a4c3238c 676 *
lorcansmith 0:2a53a4c3238c 677 * @param p first pbuf of chain
lorcansmith 0:2a53a4c3238c 678 * @return the number of pbufs in a chain
lorcansmith 0:2a53a4c3238c 679 */
lorcansmith 0:2a53a4c3238c 680
lorcansmith 0:2a53a4c3238c 681 u8_t
lorcansmith 0:2a53a4c3238c 682 pbuf_clen(struct pbuf *p)
lorcansmith 0:2a53a4c3238c 683 {
lorcansmith 0:2a53a4c3238c 684 u8_t len;
lorcansmith 0:2a53a4c3238c 685
lorcansmith 0:2a53a4c3238c 686 len = 0;
lorcansmith 0:2a53a4c3238c 687 while (p != NULL) {
lorcansmith 0:2a53a4c3238c 688 ++len;
lorcansmith 0:2a53a4c3238c 689 p = p->next;
lorcansmith 0:2a53a4c3238c 690 }
lorcansmith 0:2a53a4c3238c 691 return len;
lorcansmith 0:2a53a4c3238c 692 }
lorcansmith 0:2a53a4c3238c 693
lorcansmith 0:2a53a4c3238c 694 /**
lorcansmith 0:2a53a4c3238c 695 * Increment the reference count of the pbuf.
lorcansmith 0:2a53a4c3238c 696 *
lorcansmith 0:2a53a4c3238c 697 * @param p pbuf to increase reference counter of
lorcansmith 0:2a53a4c3238c 698 *
lorcansmith 0:2a53a4c3238c 699 */
lorcansmith 0:2a53a4c3238c 700 void
lorcansmith 0:2a53a4c3238c 701 pbuf_ref(struct pbuf *p)
lorcansmith 0:2a53a4c3238c 702 {
lorcansmith 0:2a53a4c3238c 703 SYS_ARCH_DECL_PROTECT(old_level);
lorcansmith 0:2a53a4c3238c 704 /* pbuf given? */
lorcansmith 0:2a53a4c3238c 705 if (p != NULL) {
lorcansmith 0:2a53a4c3238c 706 SYS_ARCH_PROTECT(old_level);
lorcansmith 0:2a53a4c3238c 707 ++(p->ref);
lorcansmith 0:2a53a4c3238c 708 SYS_ARCH_UNPROTECT(old_level);
lorcansmith 0:2a53a4c3238c 709 }
lorcansmith 0:2a53a4c3238c 710 }
lorcansmith 0:2a53a4c3238c 711
lorcansmith 0:2a53a4c3238c 712 /**
lorcansmith 0:2a53a4c3238c 713 * Concatenate two pbufs (each may be a pbuf chain) and take over
lorcansmith 0:2a53a4c3238c 714 * the caller's reference of the tail pbuf.
lorcansmith 0:2a53a4c3238c 715 *
lorcansmith 0:2a53a4c3238c 716 * @note The caller MAY NOT reference the tail pbuf afterwards.
lorcansmith 0:2a53a4c3238c 717 * Use pbuf_chain() for that purpose.
lorcansmith 0:2a53a4c3238c 718 *
lorcansmith 0:2a53a4c3238c 719 * @see pbuf_chain()
lorcansmith 0:2a53a4c3238c 720 */
lorcansmith 0:2a53a4c3238c 721
lorcansmith 0:2a53a4c3238c 722 void
lorcansmith 0:2a53a4c3238c 723 pbuf_cat(struct pbuf *h, struct pbuf *t)
lorcansmith 0:2a53a4c3238c 724 {
lorcansmith 0:2a53a4c3238c 725 struct pbuf *p;
lorcansmith 0:2a53a4c3238c 726
lorcansmith 0:2a53a4c3238c 727 LWIP_ERROR("(h != NULL) && (t != NULL) (programmer violates API)",
lorcansmith 0:2a53a4c3238c 728 ((h != NULL) && (t != NULL)), return;);
lorcansmith 0:2a53a4c3238c 729
lorcansmith 0:2a53a4c3238c 730 /* proceed to last pbuf of chain */
lorcansmith 0:2a53a4c3238c 731 for (p = h; p->next != NULL; p = p->next) {
lorcansmith 0:2a53a4c3238c 732 /* add total length of second chain to all totals of first chain */
lorcansmith 0:2a53a4c3238c 733 p->tot_len += t->tot_len;
lorcansmith 0:2a53a4c3238c 734 }
lorcansmith 0:2a53a4c3238c 735 /* { p is last pbuf of first h chain, p->next == NULL } */
lorcansmith 0:2a53a4c3238c 736 LWIP_ASSERT("p->tot_len == p->len (of last pbuf in chain)", p->tot_len == p->len);
lorcansmith 0:2a53a4c3238c 737 LWIP_ASSERT("p->next == NULL", p->next == NULL);
lorcansmith 0:2a53a4c3238c 738 /* add total length of second chain to last pbuf total of first chain */
lorcansmith 0:2a53a4c3238c 739 p->tot_len += t->tot_len;
lorcansmith 0:2a53a4c3238c 740 /* chain last pbuf of head (p) with first of tail (t) */
lorcansmith 0:2a53a4c3238c 741 p->next = t;
lorcansmith 0:2a53a4c3238c 742 /* p->next now references t, but the caller will drop its reference to t,
lorcansmith 0:2a53a4c3238c 743 * so netto there is no change to the reference count of t.
lorcansmith 0:2a53a4c3238c 744 */
lorcansmith 0:2a53a4c3238c 745 }
lorcansmith 0:2a53a4c3238c 746
lorcansmith 0:2a53a4c3238c 747 /**
lorcansmith 0:2a53a4c3238c 748 * Chain two pbufs (or pbuf chains) together.
lorcansmith 0:2a53a4c3238c 749 *
lorcansmith 0:2a53a4c3238c 750 * The caller MUST call pbuf_free(t) once it has stopped
lorcansmith 0:2a53a4c3238c 751 * using it. Use pbuf_cat() instead if you no longer use t.
lorcansmith 0:2a53a4c3238c 752 *
lorcansmith 0:2a53a4c3238c 753 * @param h head pbuf (chain)
lorcansmith 0:2a53a4c3238c 754 * @param t tail pbuf (chain)
lorcansmith 0:2a53a4c3238c 755 * @note The pbufs MUST belong to the same packet.
lorcansmith 0:2a53a4c3238c 756 * @note MAY NOT be called on a packet queue.
lorcansmith 0:2a53a4c3238c 757 *
lorcansmith 0:2a53a4c3238c 758 * The ->tot_len fields of all pbufs of the head chain are adjusted.
lorcansmith 0:2a53a4c3238c 759 * The ->next field of the last pbuf of the head chain is adjusted.
lorcansmith 0:2a53a4c3238c 760 * The ->ref field of the first pbuf of the tail chain is adjusted.
lorcansmith 0:2a53a4c3238c 761 *
lorcansmith 0:2a53a4c3238c 762 */
lorcansmith 0:2a53a4c3238c 763 void
lorcansmith 0:2a53a4c3238c 764 pbuf_chain(struct pbuf *h, struct pbuf *t)
lorcansmith 0:2a53a4c3238c 765 {
lorcansmith 0:2a53a4c3238c 766 pbuf_cat(h, t);
lorcansmith 0:2a53a4c3238c 767 /* t is now referenced by h */
lorcansmith 0:2a53a4c3238c 768 pbuf_ref(t);
lorcansmith 0:2a53a4c3238c 769 LWIP_DEBUGF(PBUF_DEBUG | LWIP_DBG_TRACE, ("pbuf_chain: %p references %p\n", (void *)h, (void *)t));
lorcansmith 0:2a53a4c3238c 770 }
lorcansmith 0:2a53a4c3238c 771
lorcansmith 0:2a53a4c3238c 772 /**
lorcansmith 0:2a53a4c3238c 773 * Dechains the first pbuf from its succeeding pbufs in the chain.
lorcansmith 0:2a53a4c3238c 774 *
lorcansmith 0:2a53a4c3238c 775 * Makes p->tot_len field equal to p->len.
lorcansmith 0:2a53a4c3238c 776 * @param p pbuf to dechain
lorcansmith 0:2a53a4c3238c 777 * @return remainder of the pbuf chain, or NULL if it was de-allocated.
lorcansmith 0:2a53a4c3238c 778 * @note May not be called on a packet queue.
lorcansmith 0:2a53a4c3238c 779 */
lorcansmith 0:2a53a4c3238c 780 struct pbuf *
lorcansmith 0:2a53a4c3238c 781 pbuf_dechain(struct pbuf *p)
lorcansmith 0:2a53a4c3238c 782 {
lorcansmith 0:2a53a4c3238c 783 struct pbuf *q;
lorcansmith 0:2a53a4c3238c 784 u8_t tail_gone = 1;
lorcansmith 0:2a53a4c3238c 785 /* tail */
lorcansmith 0:2a53a4c3238c 786 q = p->next;
lorcansmith 0:2a53a4c3238c 787 /* pbuf has successor in chain? */
lorcansmith 0:2a53a4c3238c 788 if (q != NULL) {
lorcansmith 0:2a53a4c3238c 789 /* assert tot_len invariant: (p->tot_len == p->len + (p->next? p->next->tot_len: 0) */
lorcansmith 0:2a53a4c3238c 790 LWIP_ASSERT("p->tot_len == p->len + q->tot_len", q->tot_len == p->tot_len - p->len);
lorcansmith 0:2a53a4c3238c 791 /* enforce invariant if assertion is disabled */
lorcansmith 0:2a53a4c3238c 792 q->tot_len = p->tot_len - p->len;
lorcansmith 0:2a53a4c3238c 793 /* decouple pbuf from remainder */
lorcansmith 0:2a53a4c3238c 794 p->next = NULL;
lorcansmith 0:2a53a4c3238c 795 /* total length of pbuf p is its own length only */
lorcansmith 0:2a53a4c3238c 796 p->tot_len = p->len;
lorcansmith 0:2a53a4c3238c 797 /* q is no longer referenced by p, free it */
lorcansmith 0:2a53a4c3238c 798 LWIP_DEBUGF(PBUF_DEBUG | LWIP_DBG_TRACE, ("pbuf_dechain: unreferencing %p\n", (void *)q));
lorcansmith 0:2a53a4c3238c 799 tail_gone = pbuf_free(q);
lorcansmith 0:2a53a4c3238c 800 if (tail_gone > 0) {
lorcansmith 0:2a53a4c3238c 801 LWIP_DEBUGF(PBUF_DEBUG | LWIP_DBG_TRACE,
lorcansmith 0:2a53a4c3238c 802 ("pbuf_dechain: deallocated %p (as it is no longer referenced)\n", (void *)q));
lorcansmith 0:2a53a4c3238c 803 }
lorcansmith 0:2a53a4c3238c 804 /* return remaining tail or NULL if deallocated */
lorcansmith 0:2a53a4c3238c 805 }
lorcansmith 0:2a53a4c3238c 806 /* assert tot_len invariant: (p->tot_len == p->len + (p->next? p->next->tot_len: 0) */
lorcansmith 0:2a53a4c3238c 807 LWIP_ASSERT("p->tot_len == p->len", p->tot_len == p->len);
lorcansmith 0:2a53a4c3238c 808 return ((tail_gone > 0) ? NULL : q);
lorcansmith 0:2a53a4c3238c 809 }
lorcansmith 0:2a53a4c3238c 810
lorcansmith 0:2a53a4c3238c 811 /**
lorcansmith 0:2a53a4c3238c 812 *
lorcansmith 0:2a53a4c3238c 813 * Create PBUF_RAM copies of pbufs.
lorcansmith 0:2a53a4c3238c 814 *
lorcansmith 0:2a53a4c3238c 815 * Used to queue packets on behalf of the lwIP stack, such as
lorcansmith 0:2a53a4c3238c 816 * ARP based queueing.
lorcansmith 0:2a53a4c3238c 817 *
lorcansmith 0:2a53a4c3238c 818 * @note You MUST explicitly use p = pbuf_take(p);
lorcansmith 0:2a53a4c3238c 819 *
lorcansmith 0:2a53a4c3238c 820 * @note Only one packet is copied, no packet queue!
lorcansmith 0:2a53a4c3238c 821 *
lorcansmith 0:2a53a4c3238c 822 * @param p_to pbuf destination of the copy
lorcansmith 0:2a53a4c3238c 823 * @param p_from pbuf source of the copy
lorcansmith 0:2a53a4c3238c 824 *
lorcansmith 0:2a53a4c3238c 825 * @return ERR_OK if pbuf was copied
lorcansmith 0:2a53a4c3238c 826 * ERR_ARG if one of the pbufs is NULL or p_to is not big
lorcansmith 0:2a53a4c3238c 827 * enough to hold p_from
lorcansmith 0:2a53a4c3238c 828 */
lorcansmith 0:2a53a4c3238c 829 err_t
lorcansmith 0:2a53a4c3238c 830 pbuf_copy(struct pbuf *p_to, struct pbuf *p_from)
lorcansmith 0:2a53a4c3238c 831 {
lorcansmith 0:2a53a4c3238c 832 u16_t offset_to=0, offset_from=0, len;
lorcansmith 0:2a53a4c3238c 833
lorcansmith 0:2a53a4c3238c 834 LWIP_DEBUGF(PBUF_DEBUG | LWIP_DBG_TRACE, ("pbuf_copy(%p, %p)\n",
lorcansmith 0:2a53a4c3238c 835 (void*)p_to, (void*)p_from));
lorcansmith 0:2a53a4c3238c 836
lorcansmith 0:2a53a4c3238c 837 /* is the target big enough to hold the source? */
lorcansmith 0:2a53a4c3238c 838 LWIP_ERROR("pbuf_copy: target not big enough to hold source", ((p_to != NULL) &&
lorcansmith 0:2a53a4c3238c 839 (p_from != NULL) && (p_to->tot_len >= p_from->tot_len)), return ERR_ARG;);
lorcansmith 0:2a53a4c3238c 840
lorcansmith 0:2a53a4c3238c 841 /* iterate through pbuf chain */
lorcansmith 0:2a53a4c3238c 842 do
lorcansmith 0:2a53a4c3238c 843 {
lorcansmith 0:2a53a4c3238c 844 LWIP_ASSERT("p_to != NULL", p_to != NULL);
lorcansmith 0:2a53a4c3238c 845 /* copy one part of the original chain */
lorcansmith 0:2a53a4c3238c 846 if ((p_to->len - offset_to) >= (p_from->len - offset_from)) {
lorcansmith 0:2a53a4c3238c 847 /* complete current p_from fits into current p_to */
lorcansmith 0:2a53a4c3238c 848 len = p_from->len - offset_from;
lorcansmith 0:2a53a4c3238c 849 } else {
lorcansmith 0:2a53a4c3238c 850 /* current p_from does not fit into current p_to */
lorcansmith 0:2a53a4c3238c 851 len = p_to->len - offset_to;
lorcansmith 0:2a53a4c3238c 852 }
lorcansmith 0:2a53a4c3238c 853 MEMCPY((u8_t*)p_to->payload + offset_to, (u8_t*)p_from->payload + offset_from, len);
lorcansmith 0:2a53a4c3238c 854 offset_to += len;
lorcansmith 0:2a53a4c3238c 855 offset_from += len;
lorcansmith 0:2a53a4c3238c 856 LWIP_ASSERT("offset_to <= p_to->len", offset_to <= p_to->len);
lorcansmith 0:2a53a4c3238c 857 if (offset_to == p_to->len) {
lorcansmith 0:2a53a4c3238c 858 /* on to next p_to (if any) */
lorcansmith 0:2a53a4c3238c 859 offset_to = 0;
lorcansmith 0:2a53a4c3238c 860 p_to = p_to->next;
lorcansmith 0:2a53a4c3238c 861 }
lorcansmith 0:2a53a4c3238c 862 LWIP_ASSERT("offset_from <= p_from->len", offset_from <= p_from->len);
lorcansmith 0:2a53a4c3238c 863 if (offset_from >= p_from->len) {
lorcansmith 0:2a53a4c3238c 864 /* on to next p_from (if any) */
lorcansmith 0:2a53a4c3238c 865 offset_from = 0;
lorcansmith 0:2a53a4c3238c 866 p_from = p_from->next;
lorcansmith 0:2a53a4c3238c 867 }
lorcansmith 0:2a53a4c3238c 868
lorcansmith 0:2a53a4c3238c 869 if((p_from != NULL) && (p_from->len == p_from->tot_len)) {
lorcansmith 0:2a53a4c3238c 870 /* don't copy more than one packet! */
lorcansmith 0:2a53a4c3238c 871 LWIP_ERROR("pbuf_copy() does not allow packet queues!\n",
lorcansmith 0:2a53a4c3238c 872 (p_from->next == NULL), return ERR_VAL;);
lorcansmith 0:2a53a4c3238c 873 }
lorcansmith 0:2a53a4c3238c 874 if((p_to != NULL) && (p_to->len == p_to->tot_len)) {
lorcansmith 0:2a53a4c3238c 875 /* don't copy more than one packet! */
lorcansmith 0:2a53a4c3238c 876 LWIP_ERROR("pbuf_copy() does not allow packet queues!\n",
lorcansmith 0:2a53a4c3238c 877 (p_to->next == NULL), return ERR_VAL;);
lorcansmith 0:2a53a4c3238c 878 }
lorcansmith 0:2a53a4c3238c 879 } while (p_from);
lorcansmith 0:2a53a4c3238c 880 LWIP_DEBUGF(PBUF_DEBUG | LWIP_DBG_TRACE, ("pbuf_copy: end of chain reached.\n"));
lorcansmith 0:2a53a4c3238c 881 return ERR_OK;
lorcansmith 0:2a53a4c3238c 882 }
lorcansmith 0:2a53a4c3238c 883
lorcansmith 0:2a53a4c3238c 884 /**
lorcansmith 0:2a53a4c3238c 885 * Copy (part of) the contents of a packet buffer
lorcansmith 0:2a53a4c3238c 886 * to an application supplied buffer.
lorcansmith 0:2a53a4c3238c 887 *
lorcansmith 0:2a53a4c3238c 888 * @param buf the pbuf from which to copy data
lorcansmith 0:2a53a4c3238c 889 * @param dataptr the application supplied buffer
lorcansmith 0:2a53a4c3238c 890 * @param len length of data to copy (dataptr must be big enough). No more
lorcansmith 0:2a53a4c3238c 891 * than buf->tot_len will be copied, irrespective of len
lorcansmith 0:2a53a4c3238c 892 * @param offset offset into the packet buffer from where to begin copying len bytes
lorcansmith 0:2a53a4c3238c 893 * @return the number of bytes copied, or 0 on failure
lorcansmith 0:2a53a4c3238c 894 */
lorcansmith 0:2a53a4c3238c 895 u16_t
lorcansmith 0:2a53a4c3238c 896 pbuf_copy_partial(struct pbuf *buf, void *dataptr, u16_t len, u16_t offset)
lorcansmith 0:2a53a4c3238c 897 {
lorcansmith 0:2a53a4c3238c 898 struct pbuf *p;
lorcansmith 0:2a53a4c3238c 899 u16_t left;
lorcansmith 0:2a53a4c3238c 900 u16_t buf_copy_len;
lorcansmith 0:2a53a4c3238c 901 u16_t copied_total = 0;
lorcansmith 0:2a53a4c3238c 902
lorcansmith 0:2a53a4c3238c 903 LWIP_ERROR("pbuf_copy_partial: invalid buf", (buf != NULL), return 0;);
lorcansmith 0:2a53a4c3238c 904 LWIP_ERROR("pbuf_copy_partial: invalid dataptr", (dataptr != NULL), return 0;);
lorcansmith 0:2a53a4c3238c 905
lorcansmith 0:2a53a4c3238c 906 left = 0;
lorcansmith 0:2a53a4c3238c 907
lorcansmith 0:2a53a4c3238c 908 if((buf == NULL) || (dataptr == NULL)) {
lorcansmith 0:2a53a4c3238c 909 return 0;
lorcansmith 0:2a53a4c3238c 910 }
lorcansmith 0:2a53a4c3238c 911
lorcansmith 0:2a53a4c3238c 912 /* Note some systems use byte copy if dataptr or one of the pbuf payload pointers are unaligned. */
lorcansmith 0:2a53a4c3238c 913 for(p = buf; len != 0 && p != NULL; p = p->next) {
lorcansmith 0:2a53a4c3238c 914 if ((offset != 0) && (offset >= p->len)) {
lorcansmith 0:2a53a4c3238c 915 /* don't copy from this buffer -> on to the next */
lorcansmith 0:2a53a4c3238c 916 offset -= p->len;
lorcansmith 0:2a53a4c3238c 917 } else {
lorcansmith 0:2a53a4c3238c 918 /* copy from this buffer. maybe only partially. */
lorcansmith 0:2a53a4c3238c 919 buf_copy_len = p->len - offset;
lorcansmith 0:2a53a4c3238c 920 if (buf_copy_len > len)
lorcansmith 0:2a53a4c3238c 921 buf_copy_len = len;
lorcansmith 0:2a53a4c3238c 922 /* copy the necessary parts of the buffer */
lorcansmith 0:2a53a4c3238c 923 MEMCPY(&((char*)dataptr)[left], &((char*)p->payload)[offset], buf_copy_len);
lorcansmith 0:2a53a4c3238c 924 copied_total += buf_copy_len;
lorcansmith 0:2a53a4c3238c 925 left += buf_copy_len;
lorcansmith 0:2a53a4c3238c 926 len -= buf_copy_len;
lorcansmith 0:2a53a4c3238c 927 offset = 0;
lorcansmith 0:2a53a4c3238c 928 }
lorcansmith 0:2a53a4c3238c 929 }
lorcansmith 0:2a53a4c3238c 930 return copied_total;
lorcansmith 0:2a53a4c3238c 931 }
lorcansmith 0:2a53a4c3238c 932
lorcansmith 0:2a53a4c3238c 933 /**
lorcansmith 0:2a53a4c3238c 934 * Copy application supplied data into a pbuf.
lorcansmith 0:2a53a4c3238c 935 * This function can only be used to copy the equivalent of buf->tot_len data.
lorcansmith 0:2a53a4c3238c 936 *
lorcansmith 0:2a53a4c3238c 937 * @param buf pbuf to fill with data
lorcansmith 0:2a53a4c3238c 938 * @param dataptr application supplied data buffer
lorcansmith 0:2a53a4c3238c 939 * @param len length of the application supplied data buffer
lorcansmith 0:2a53a4c3238c 940 *
lorcansmith 0:2a53a4c3238c 941 * @return ERR_OK if successful, ERR_MEM if the pbuf is not big enough
lorcansmith 0:2a53a4c3238c 942 */
lorcansmith 0:2a53a4c3238c 943 err_t
lorcansmith 0:2a53a4c3238c 944 pbuf_take(struct pbuf *buf, const void *dataptr, u16_t len)
lorcansmith 0:2a53a4c3238c 945 {
lorcansmith 0:2a53a4c3238c 946 struct pbuf *p;
lorcansmith 0:2a53a4c3238c 947 u16_t buf_copy_len;
lorcansmith 0:2a53a4c3238c 948 u16_t total_copy_len = len;
lorcansmith 0:2a53a4c3238c 949 u16_t copied_total = 0;
lorcansmith 0:2a53a4c3238c 950
lorcansmith 0:2a53a4c3238c 951 LWIP_ERROR("pbuf_take: invalid buf", (buf != NULL), return 0;);
lorcansmith 0:2a53a4c3238c 952 LWIP_ERROR("pbuf_take: invalid dataptr", (dataptr != NULL), return 0;);
lorcansmith 0:2a53a4c3238c 953
lorcansmith 0:2a53a4c3238c 954 if ((buf == NULL) || (dataptr == NULL) || (buf->tot_len < len)) {
lorcansmith 0:2a53a4c3238c 955 return ERR_ARG;
lorcansmith 0:2a53a4c3238c 956 }
lorcansmith 0:2a53a4c3238c 957
lorcansmith 0:2a53a4c3238c 958 /* Note some systems use byte copy if dataptr or one of the pbuf payload pointers are unaligned. */
lorcansmith 0:2a53a4c3238c 959 for(p = buf; total_copy_len != 0; p = p->next) {
lorcansmith 0:2a53a4c3238c 960 LWIP_ASSERT("pbuf_take: invalid pbuf", p != NULL);
lorcansmith 0:2a53a4c3238c 961 buf_copy_len = total_copy_len;
lorcansmith 0:2a53a4c3238c 962 if (buf_copy_len > p->len) {
lorcansmith 0:2a53a4c3238c 963 /* this pbuf cannot hold all remaining data */
lorcansmith 0:2a53a4c3238c 964 buf_copy_len = p->len;
lorcansmith 0:2a53a4c3238c 965 }
lorcansmith 0:2a53a4c3238c 966 /* copy the necessary parts of the buffer */
lorcansmith 0:2a53a4c3238c 967 MEMCPY(p->payload, &((char*)dataptr)[copied_total], buf_copy_len);
lorcansmith 0:2a53a4c3238c 968 total_copy_len -= buf_copy_len;
lorcansmith 0:2a53a4c3238c 969 copied_total += buf_copy_len;
lorcansmith 0:2a53a4c3238c 970 }
lorcansmith 0:2a53a4c3238c 971 LWIP_ASSERT("did not copy all data", total_copy_len == 0 && copied_total == len);
lorcansmith 0:2a53a4c3238c 972 return ERR_OK;
lorcansmith 0:2a53a4c3238c 973 }
lorcansmith 0:2a53a4c3238c 974
lorcansmith 0:2a53a4c3238c 975 /**
lorcansmith 0:2a53a4c3238c 976 * Creates a single pbuf out of a queue of pbufs.
lorcansmith 0:2a53a4c3238c 977 *
lorcansmith 0:2a53a4c3238c 978 * @remark: Either the source pbuf 'p' is freed by this function or the original
lorcansmith 0:2a53a4c3238c 979 * pbuf 'p' is returned, therefore the caller has to check the result!
lorcansmith 0:2a53a4c3238c 980 *
lorcansmith 0:2a53a4c3238c 981 * @param p the source pbuf
lorcansmith 0:2a53a4c3238c 982 * @param layer pbuf_layer of the new pbuf
lorcansmith 0:2a53a4c3238c 983 *
lorcansmith 0:2a53a4c3238c 984 * @return a new, single pbuf (p->next is NULL)
lorcansmith 0:2a53a4c3238c 985 * or the old pbuf if allocation fails
lorcansmith 0:2a53a4c3238c 986 */
lorcansmith 0:2a53a4c3238c 987 struct pbuf*
lorcansmith 0:2a53a4c3238c 988 pbuf_coalesce(struct pbuf *p, pbuf_layer layer)
lorcansmith 0:2a53a4c3238c 989 {
lorcansmith 0:2a53a4c3238c 990 struct pbuf *q;
lorcansmith 0:2a53a4c3238c 991 err_t err;
lorcansmith 0:2a53a4c3238c 992 if (p->next == NULL) {
lorcansmith 0:2a53a4c3238c 993 return p;
lorcansmith 0:2a53a4c3238c 994 }
lorcansmith 0:2a53a4c3238c 995 q = pbuf_alloc(layer, p->tot_len, PBUF_RAM);
lorcansmith 0:2a53a4c3238c 996 if (q == NULL) {
lorcansmith 0:2a53a4c3238c 997 /* @todo: what do we do now? */
lorcansmith 0:2a53a4c3238c 998 return p;
lorcansmith 0:2a53a4c3238c 999 }
lorcansmith 0:2a53a4c3238c 1000 err = pbuf_copy(q, p);
lorcansmith 0:2a53a4c3238c 1001 LWIP_ASSERT("pbuf_copy failed", err == ERR_OK);
lorcansmith 0:2a53a4c3238c 1002 pbuf_free(p);
lorcansmith 0:2a53a4c3238c 1003 return q;
lorcansmith 0:2a53a4c3238c 1004 }
lorcansmith 0:2a53a4c3238c 1005
lorcansmith 0:2a53a4c3238c 1006 #if LWIP_CHECKSUM_ON_COPY
lorcansmith 0:2a53a4c3238c 1007 /**
lorcansmith 0:2a53a4c3238c 1008 * Copies data into a single pbuf (*not* into a pbuf queue!) and updates
lorcansmith 0:2a53a4c3238c 1009 * the checksum while copying
lorcansmith 0:2a53a4c3238c 1010 *
lorcansmith 0:2a53a4c3238c 1011 * @param p the pbuf to copy data into
lorcansmith 0:2a53a4c3238c 1012 * @param start_offset offset of p->payload where to copy the data to
lorcansmith 0:2a53a4c3238c 1013 * @param dataptr data to copy into the pbuf
lorcansmith 0:2a53a4c3238c 1014 * @param len length of data to copy into the pbuf
lorcansmith 0:2a53a4c3238c 1015 * @param chksum pointer to the checksum which is updated
lorcansmith 0:2a53a4c3238c 1016 * @return ERR_OK if successful, another error if the data does not fit
lorcansmith 0:2a53a4c3238c 1017 * within the (first) pbuf (no pbuf queues!)
lorcansmith 0:2a53a4c3238c 1018 */
lorcansmith 0:2a53a4c3238c 1019 err_t
lorcansmith 0:2a53a4c3238c 1020 pbuf_fill_chksum(struct pbuf *p, u16_t start_offset, const void *dataptr,
lorcansmith 0:2a53a4c3238c 1021 u16_t len, u16_t *chksum)
lorcansmith 0:2a53a4c3238c 1022 {
lorcansmith 0:2a53a4c3238c 1023 u32_t acc;
lorcansmith 0:2a53a4c3238c 1024 u16_t copy_chksum;
lorcansmith 0:2a53a4c3238c 1025 char *dst_ptr;
lorcansmith 0:2a53a4c3238c 1026 LWIP_ASSERT("p != NULL", p != NULL);
lorcansmith 0:2a53a4c3238c 1027 LWIP_ASSERT("dataptr != NULL", dataptr != NULL);
lorcansmith 0:2a53a4c3238c 1028 LWIP_ASSERT("chksum != NULL", chksum != NULL);
lorcansmith 0:2a53a4c3238c 1029 LWIP_ASSERT("len != 0", len != 0);
lorcansmith 0:2a53a4c3238c 1030
lorcansmith 0:2a53a4c3238c 1031 if ((start_offset >= p->len) || (start_offset + len > p->len)) {
lorcansmith 0:2a53a4c3238c 1032 return ERR_ARG;
lorcansmith 0:2a53a4c3238c 1033 }
lorcansmith 0:2a53a4c3238c 1034
lorcansmith 0:2a53a4c3238c 1035 dst_ptr = ((char*)p->payload) + start_offset;
lorcansmith 0:2a53a4c3238c 1036 copy_chksum = LWIP_CHKSUM_COPY(dst_ptr, dataptr, len);
lorcansmith 0:2a53a4c3238c 1037 if ((start_offset & 1) != 0) {
lorcansmith 0:2a53a4c3238c 1038 copy_chksum = SWAP_BYTES_IN_WORD(copy_chksum);
lorcansmith 0:2a53a4c3238c 1039 }
lorcansmith 0:2a53a4c3238c 1040 acc = *chksum;
lorcansmith 0:2a53a4c3238c 1041 acc += copy_chksum;
lorcansmith 0:2a53a4c3238c 1042 *chksum = FOLD_U32T(acc);
lorcansmith 0:2a53a4c3238c 1043 return ERR_OK;
lorcansmith 0:2a53a4c3238c 1044 }
lorcansmith 0:2a53a4c3238c 1045 #endif /* LWIP_CHECKSUM_ON_COPY */
lorcansmith 0:2a53a4c3238c 1046
lorcansmith 0:2a53a4c3238c 1047 /** Get one byte from the specified position in a pbuf
lorcansmith 0:2a53a4c3238c 1048 * WARNING: returns zero for offset >= p->tot_len
lorcansmith 0:2a53a4c3238c 1049 *
lorcansmith 0:2a53a4c3238c 1050 * @param p pbuf to parse
lorcansmith 0:2a53a4c3238c 1051 * @param offset offset into p of the byte to return
lorcansmith 0:2a53a4c3238c 1052 * @return byte at an offset into p OR ZERO IF 'offset' >= p->tot_len
lorcansmith 0:2a53a4c3238c 1053 */
lorcansmith 0:2a53a4c3238c 1054 u8_t
lorcansmith 0:2a53a4c3238c 1055 pbuf_get_at(struct pbuf* p, u16_t offset)
lorcansmith 0:2a53a4c3238c 1056 {
lorcansmith 0:2a53a4c3238c 1057 u16_t copy_from = offset;
lorcansmith 0:2a53a4c3238c 1058 struct pbuf* q = p;
lorcansmith 0:2a53a4c3238c 1059
lorcansmith 0:2a53a4c3238c 1060 /* get the correct pbuf */
lorcansmith 0:2a53a4c3238c 1061 while ((q != NULL) && (q->len <= copy_from)) {
lorcansmith 0:2a53a4c3238c 1062 copy_from -= q->len;
lorcansmith 0:2a53a4c3238c 1063 q = q->next;
lorcansmith 0:2a53a4c3238c 1064 }
lorcansmith 0:2a53a4c3238c 1065 /* return requested data if pbuf is OK */
lorcansmith 0:2a53a4c3238c 1066 if ((q != NULL) && (q->len > copy_from)) {
lorcansmith 0:2a53a4c3238c 1067 return ((u8_t*)q->payload)[copy_from];
lorcansmith 0:2a53a4c3238c 1068 }
lorcansmith 0:2a53a4c3238c 1069 return 0;
lorcansmith 0:2a53a4c3238c 1070 }
lorcansmith 0:2a53a4c3238c 1071
lorcansmith 0:2a53a4c3238c 1072 /** Compare pbuf contents at specified offset with memory s2, both of length n
lorcansmith 0:2a53a4c3238c 1073 *
lorcansmith 0:2a53a4c3238c 1074 * @param p pbuf to compare
lorcansmith 0:2a53a4c3238c 1075 * @param offset offset into p at wich to start comparing
lorcansmith 0:2a53a4c3238c 1076 * @param s2 buffer to compare
lorcansmith 0:2a53a4c3238c 1077 * @param n length of buffer to compare
lorcansmith 0:2a53a4c3238c 1078 * @return zero if equal, nonzero otherwise
lorcansmith 0:2a53a4c3238c 1079 * (0xffff if p is too short, diffoffset+1 otherwise)
lorcansmith 0:2a53a4c3238c 1080 */
lorcansmith 0:2a53a4c3238c 1081 u16_t
lorcansmith 0:2a53a4c3238c 1082 pbuf_memcmp(struct pbuf* p, u16_t offset, const void* s2, u16_t n)
lorcansmith 0:2a53a4c3238c 1083 {
lorcansmith 0:2a53a4c3238c 1084 u16_t start = offset;
lorcansmith 0:2a53a4c3238c 1085 struct pbuf* q = p;
lorcansmith 0:2a53a4c3238c 1086
lorcansmith 0:2a53a4c3238c 1087 /* get the correct pbuf */
lorcansmith 0:2a53a4c3238c 1088 while ((q != NULL) && (q->len <= start)) {
lorcansmith 0:2a53a4c3238c 1089 start -= q->len;
lorcansmith 0:2a53a4c3238c 1090 q = q->next;
lorcansmith 0:2a53a4c3238c 1091 }
lorcansmith 0:2a53a4c3238c 1092 /* return requested data if pbuf is OK */
lorcansmith 0:2a53a4c3238c 1093 if ((q != NULL) && (q->len > start)) {
lorcansmith 0:2a53a4c3238c 1094 u16_t i;
lorcansmith 0:2a53a4c3238c 1095 for(i = 0; i < n; i++) {
lorcansmith 0:2a53a4c3238c 1096 u8_t a = pbuf_get_at(q, start + i);
lorcansmith 0:2a53a4c3238c 1097 u8_t b = ((u8_t*)s2)[i];
lorcansmith 0:2a53a4c3238c 1098 if (a != b) {
lorcansmith 0:2a53a4c3238c 1099 return i+1;
lorcansmith 0:2a53a4c3238c 1100 }
lorcansmith 0:2a53a4c3238c 1101 }
lorcansmith 0:2a53a4c3238c 1102 return 0;
lorcansmith 0:2a53a4c3238c 1103 }
lorcansmith 0:2a53a4c3238c 1104 return 0xffff;
lorcansmith 0:2a53a4c3238c 1105 }
lorcansmith 0:2a53a4c3238c 1106
lorcansmith 0:2a53a4c3238c 1107 /** Find occurrence of mem (with length mem_len) in pbuf p, starting at offset
lorcansmith 0:2a53a4c3238c 1108 * start_offset.
lorcansmith 0:2a53a4c3238c 1109 *
lorcansmith 0:2a53a4c3238c 1110 * @param p pbuf to search, maximum length is 0xFFFE since 0xFFFF is used as
lorcansmith 0:2a53a4c3238c 1111 * return value 'not found'
lorcansmith 0:2a53a4c3238c 1112 * @param mem search for the contents of this buffer
lorcansmith 0:2a53a4c3238c 1113 * @param mem_len length of 'mem'
lorcansmith 0:2a53a4c3238c 1114 * @param start_offset offset into p at which to start searching
lorcansmith 0:2a53a4c3238c 1115 * @return 0xFFFF if substr was not found in p or the index where it was found
lorcansmith 0:2a53a4c3238c 1116 */
lorcansmith 0:2a53a4c3238c 1117 u16_t
lorcansmith 0:2a53a4c3238c 1118 pbuf_memfind(struct pbuf* p, const void* mem, u16_t mem_len, u16_t start_offset)
lorcansmith 0:2a53a4c3238c 1119 {
lorcansmith 0:2a53a4c3238c 1120 u16_t i;
lorcansmith 0:2a53a4c3238c 1121 u16_t max = p->tot_len - mem_len;
lorcansmith 0:2a53a4c3238c 1122 if (p->tot_len >= mem_len + start_offset) {
lorcansmith 0:2a53a4c3238c 1123 for(i = start_offset; i <= max; ) {
lorcansmith 0:2a53a4c3238c 1124 u16_t plus = pbuf_memcmp(p, i, mem, mem_len);
lorcansmith 0:2a53a4c3238c 1125 if (plus == 0) {
lorcansmith 0:2a53a4c3238c 1126 return i;
lorcansmith 0:2a53a4c3238c 1127 } else {
lorcansmith 0:2a53a4c3238c 1128 i += plus;
lorcansmith 0:2a53a4c3238c 1129 }
lorcansmith 0:2a53a4c3238c 1130 }
lorcansmith 0:2a53a4c3238c 1131 }
lorcansmith 0:2a53a4c3238c 1132 return 0xFFFF;
lorcansmith 0:2a53a4c3238c 1133 }
lorcansmith 0:2a53a4c3238c 1134
lorcansmith 0:2a53a4c3238c 1135 /** Find occurrence of substr with length substr_len in pbuf p, start at offset
lorcansmith 0:2a53a4c3238c 1136 * start_offset
lorcansmith 0:2a53a4c3238c 1137 * WARNING: in contrast to strstr(), this one does not stop at the first \0 in
lorcansmith 0:2a53a4c3238c 1138 * the pbuf/source string!
lorcansmith 0:2a53a4c3238c 1139 *
lorcansmith 0:2a53a4c3238c 1140 * @param p pbuf to search, maximum length is 0xFFFE since 0xFFFF is used as
lorcansmith 0:2a53a4c3238c 1141 * return value 'not found'
lorcansmith 0:2a53a4c3238c 1142 * @param substr string to search for in p, maximum length is 0xFFFE
lorcansmith 0:2a53a4c3238c 1143 * @return 0xFFFF if substr was not found in p or the index where it was found
lorcansmith 0:2a53a4c3238c 1144 */
lorcansmith 0:2a53a4c3238c 1145 u16_t
lorcansmith 0:2a53a4c3238c 1146 pbuf_strstr(struct pbuf* p, const char* substr)
lorcansmith 0:2a53a4c3238c 1147 {
lorcansmith 0:2a53a4c3238c 1148 size_t substr_len;
lorcansmith 0:2a53a4c3238c 1149 if ((substr == NULL) || (substr[0] == 0) || (p->tot_len == 0xFFFF)) {
lorcansmith 0:2a53a4c3238c 1150 return 0xFFFF;
lorcansmith 0:2a53a4c3238c 1151 }
lorcansmith 0:2a53a4c3238c 1152 substr_len = strlen(substr);
lorcansmith 0:2a53a4c3238c 1153 if (substr_len >= 0xFFFF) {
lorcansmith 0:2a53a4c3238c 1154 return 0xFFFF;
lorcansmith 0:2a53a4c3238c 1155 }
lorcansmith 0:2a53a4c3238c 1156 return pbuf_memfind(p, substr, (u16_t)substr_len, 0);
lorcansmith 0:2a53a4c3238c 1157 }