mbed unsupported / lwip

A version of LWIP, provided for backwards compatibility.

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trunk/Core/lwIP/core/mem.c@0:5e1631496985, 2012-05-08 (annotated)

Committer:
root@mbed.org
Date:
Tue May 08 15:32:10 2012 +0100
Revision:
0:5e1631496985
initial commit

Who changed what in which revision?

UserRevisionLine numberNew contents of line
root@mbed.org 0:5e1631496985 1 /**
root@mbed.org 0:5e1631496985 2 * @file
root@mbed.org 0:5e1631496985 3 * Dynamic memory manager
root@mbed.org 0:5e1631496985 4 *
root@mbed.org 0:5e1631496985 5 * This is a lightweight replacement for the standard C library malloc().
root@mbed.org 0:5e1631496985 6 *
root@mbed.org 0:5e1631496985 7 * If you want to use the standard C library malloc() instead, define
root@mbed.org 0:5e1631496985 8 * MEM_LIBC_MALLOC to 1 in your lwipopts.h
root@mbed.org 0:5e1631496985 9 *
root@mbed.org 0:5e1631496985 10 * To let mem_malloc() use pools (prevents fragmentation and is much faster than
root@mbed.org 0:5e1631496985 11 * a heap but might waste some memory), define MEM_USE_POOLS to 1, define
root@mbed.org 0:5e1631496985 12 * MEM_USE_CUSTOM_POOLS to 1 and create a file "lwippools.h" that includes a list
root@mbed.org 0:5e1631496985 13 * of pools like this (more pools can be added between _START and _END):
root@mbed.org 0:5e1631496985 14 *
root@mbed.org 0:5e1631496985 15 * Define three pools with sizes 256, 512, and 1512 bytes
root@mbed.org 0:5e1631496985 16 * LWIP_MALLOC_MEMPOOL_START
root@mbed.org 0:5e1631496985 17 * LWIP_MALLOC_MEMPOOL(20, 256)
root@mbed.org 0:5e1631496985 18 * LWIP_MALLOC_MEMPOOL(10, 512)
root@mbed.org 0:5e1631496985 19 * LWIP_MALLOC_MEMPOOL(5, 1512)
root@mbed.org 0:5e1631496985 20 * LWIP_MALLOC_MEMPOOL_END
root@mbed.org 0:5e1631496985 21 */
root@mbed.org 0:5e1631496985 22
root@mbed.org 0:5e1631496985 23 /*
root@mbed.org 0:5e1631496985 24 * Copyright (c) 2001-2004 Swedish Institute of Computer Science.
root@mbed.org 0:5e1631496985 25 * All rights reserved.
root@mbed.org 0:5e1631496985 26 *
root@mbed.org 0:5e1631496985 27 * Redistribution and use in source and binary forms, with or without modification,
root@mbed.org 0:5e1631496985 28 * are permitted provided that the following conditions are met:
root@mbed.org 0:5e1631496985 29 *
root@mbed.org 0:5e1631496985 30 * 1. Redistributions of source code must retain the above copyright notice,
root@mbed.org 0:5e1631496985 31 * this list of conditions and the following disclaimer.
root@mbed.org 0:5e1631496985 32 * 2. Redistributions in binary form must reproduce the above copyright notice,
root@mbed.org 0:5e1631496985 33 * this list of conditions and the following disclaimer in the documentation
root@mbed.org 0:5e1631496985 34 * and/or other materials provided with the distribution.
root@mbed.org 0:5e1631496985 35 * 3. The name of the author may not be used to endorse or promote products
root@mbed.org 0:5e1631496985 36 * derived from this software without specific prior written permission.
root@mbed.org 0:5e1631496985 37 *
root@mbed.org 0:5e1631496985 38 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR IMPLIED
root@mbed.org 0:5e1631496985 39 * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
root@mbed.org 0:5e1631496985 40 * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT
root@mbed.org 0:5e1631496985 41 * SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
root@mbed.org 0:5e1631496985 42 * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT
root@mbed.org 0:5e1631496985 43 * OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
root@mbed.org 0:5e1631496985 44 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
root@mbed.org 0:5e1631496985 45 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
root@mbed.org 0:5e1631496985 46 * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY
root@mbed.org 0:5e1631496985 47 * OF SUCH DAMAGE.
root@mbed.org 0:5e1631496985 48 *
root@mbed.org 0:5e1631496985 49 * This file is part of the lwIP TCP/IP stack.
root@mbed.org 0:5e1631496985 50 *
root@mbed.org 0:5e1631496985 51 * Author: Adam Dunkels <adam@sics.se>
root@mbed.org 0:5e1631496985 52 * Simon Goldschmidt
root@mbed.org 0:5e1631496985 53 *
root@mbed.org 0:5e1631496985 54 */
root@mbed.org 0:5e1631496985 55
root@mbed.org 0:5e1631496985 56 #include "lwip/opt.h"
root@mbed.org 0:5e1631496985 57
root@mbed.org 0:5e1631496985 58 #if !MEM_LIBC_MALLOC /* don't build if not configured for use in lwipopts.h */
root@mbed.org 0:5e1631496985 59
root@mbed.org 0:5e1631496985 60 #include "lwip/def.h"
root@mbed.org 0:5e1631496985 61 #include "lwip/mem.h"
root@mbed.org 0:5e1631496985 62 #include "lwip/sys.h"
root@mbed.org 0:5e1631496985 63 #include "lwip/stats.h"
root@mbed.org 0:5e1631496985 64
root@mbed.org 0:5e1631496985 65 #include <string.h>
root@mbed.org 0:5e1631496985 66
root@mbed.org 0:5e1631496985 67 #if MEM_USE_POOLS
root@mbed.org 0:5e1631496985 68 /* lwIP head implemented with different sized pools */
root@mbed.org 0:5e1631496985 69
root@mbed.org 0:5e1631496985 70 /**
root@mbed.org 0:5e1631496985 71 * Allocate memory: determine the smallest pool that is big enough
root@mbed.org 0:5e1631496985 72 * to contain an element of 'size' and get an element from that pool.
root@mbed.org 0:5e1631496985 73 *
root@mbed.org 0:5e1631496985 74 * @param size the size in bytes of the memory needed
root@mbed.org 0:5e1631496985 75 * @return a pointer to the allocated memory or NULL if the pool is empty
root@mbed.org 0:5e1631496985 76 */
root@mbed.org 0:5e1631496985 77 void *
root@mbed.org 0:5e1631496985 78 mem_malloc(mem_size_t size)
root@mbed.org 0:5e1631496985 79 {
root@mbed.org 0:5e1631496985 80 struct memp_malloc_helper *element;
root@mbed.org 0:5e1631496985 81 memp_t poolnr;
root@mbed.org 0:5e1631496985 82 mem_size_t required_size = size + sizeof(struct memp_malloc_helper);
root@mbed.org 0:5e1631496985 83
root@mbed.org 0:5e1631496985 84 for (poolnr = MEMP_POOL_FIRST; poolnr <= MEMP_POOL_LAST; poolnr++) {
root@mbed.org 0:5e1631496985 85 #if MEM_USE_POOLS_TRY_BIGGER_POOL
root@mbed.org 0:5e1631496985 86 again:
root@mbed.org 0:5e1631496985 87 #endif /* MEM_USE_POOLS_TRY_BIGGER_POOL */
root@mbed.org 0:5e1631496985 88 /* is this pool big enough to hold an element of the required size
root@mbed.org 0:5e1631496985 89 plus a struct memp_malloc_helper that saves the pool this element came from? */
root@mbed.org 0:5e1631496985 90 if (required_size <= memp_sizes[poolnr]) {
root@mbed.org 0:5e1631496985 91 break;
root@mbed.org 0:5e1631496985 92 }
root@mbed.org 0:5e1631496985 93 }
root@mbed.org 0:5e1631496985 94 if (poolnr > MEMP_POOL_LAST) {
root@mbed.org 0:5e1631496985 95 LWIP_ASSERT("mem_malloc(): no pool is that big!", 0);
root@mbed.org 0:5e1631496985 96 return NULL;
root@mbed.org 0:5e1631496985 97 }
root@mbed.org 0:5e1631496985 98 element = (struct memp_malloc_helper*)memp_malloc(poolnr);
root@mbed.org 0:5e1631496985 99 if (element == NULL) {
root@mbed.org 0:5e1631496985 100 /* No need to DEBUGF or ASSERT: This error is already
root@mbed.org 0:5e1631496985 101 taken care of in memp.c */
root@mbed.org 0:5e1631496985 102 #if MEM_USE_POOLS_TRY_BIGGER_POOL
root@mbed.org 0:5e1631496985 103 /** Try a bigger pool if this one is empty! */
root@mbed.org 0:5e1631496985 104 if (poolnr < MEMP_POOL_LAST) {
root@mbed.org 0:5e1631496985 105 poolnr++;
root@mbed.org 0:5e1631496985 106 goto again;
root@mbed.org 0:5e1631496985 107 }
root@mbed.org 0:5e1631496985 108 #endif /* MEM_USE_POOLS_TRY_BIGGER_POOL */
root@mbed.org 0:5e1631496985 109 return NULL;
root@mbed.org 0:5e1631496985 110 }
root@mbed.org 0:5e1631496985 111
root@mbed.org 0:5e1631496985 112 /* save the pool number this element came from */
root@mbed.org 0:5e1631496985 113 element->poolnr = poolnr;
root@mbed.org 0:5e1631496985 114 /* and return a pointer to the memory directly after the struct memp_malloc_helper */
root@mbed.org 0:5e1631496985 115 element++;
root@mbed.org 0:5e1631496985 116
root@mbed.org 0:5e1631496985 117 return element;
root@mbed.org 0:5e1631496985 118 }
root@mbed.org 0:5e1631496985 119
root@mbed.org 0:5e1631496985 120 /**
root@mbed.org 0:5e1631496985 121 * Free memory previously allocated by mem_malloc. Loads the pool number
root@mbed.org 0:5e1631496985 122 * and calls memp_free with that pool number to put the element back into
root@mbed.org 0:5e1631496985 123 * its pool
root@mbed.org 0:5e1631496985 124 *
root@mbed.org 0:5e1631496985 125 * @param rmem the memory element to free
root@mbed.org 0:5e1631496985 126 */
root@mbed.org 0:5e1631496985 127 void
root@mbed.org 0:5e1631496985 128 mem_free(void *rmem)
root@mbed.org 0:5e1631496985 129 {
root@mbed.org 0:5e1631496985 130 struct memp_malloc_helper *hmem = (struct memp_malloc_helper*)rmem;
root@mbed.org 0:5e1631496985 131
root@mbed.org 0:5e1631496985 132 LWIP_ASSERT("rmem != NULL", (rmem != NULL));
root@mbed.org 0:5e1631496985 133 LWIP_ASSERT("rmem == MEM_ALIGN(rmem)", (rmem == LWIP_MEM_ALIGN(rmem)));
root@mbed.org 0:5e1631496985 134
root@mbed.org 0:5e1631496985 135 /* get the original struct memp_malloc_helper */
root@mbed.org 0:5e1631496985 136 hmem--;
root@mbed.org 0:5e1631496985 137
root@mbed.org 0:5e1631496985 138 LWIP_ASSERT("hmem != NULL", (hmem != NULL));
root@mbed.org 0:5e1631496985 139 LWIP_ASSERT("hmem == MEM_ALIGN(hmem)", (hmem == LWIP_MEM_ALIGN(hmem)));
root@mbed.org 0:5e1631496985 140 LWIP_ASSERT("hmem->poolnr < MEMP_MAX", (hmem->poolnr < MEMP_MAX));
root@mbed.org 0:5e1631496985 141
root@mbed.org 0:5e1631496985 142 /* and put it in the pool we saved earlier */
root@mbed.org 0:5e1631496985 143 memp_free(hmem->poolnr, hmem);
root@mbed.org 0:5e1631496985 144 }
root@mbed.org 0:5e1631496985 145
root@mbed.org 0:5e1631496985 146 #else /* MEM_USE_POOLS */
root@mbed.org 0:5e1631496985 147 /* lwIP replacement for your libc malloc() */
root@mbed.org 0:5e1631496985 148
root@mbed.org 0:5e1631496985 149 /**
root@mbed.org 0:5e1631496985 150 * The heap is made up as a list of structs of this type.
root@mbed.org 0:5e1631496985 151 * This does not have to be aligned since for getting its size,
root@mbed.org 0:5e1631496985 152 * we only use the macro SIZEOF_STRUCT_MEM, which automatically alignes.
root@mbed.org 0:5e1631496985 153 */
root@mbed.org 0:5e1631496985 154 struct mem {
root@mbed.org 0:5e1631496985 155 /** index (-> ram[next]) of the next struct */
root@mbed.org 0:5e1631496985 156 mem_size_t next;
root@mbed.org 0:5e1631496985 157 /** index (-> ram[next]) of the next struct */
root@mbed.org 0:5e1631496985 158 mem_size_t prev;
root@mbed.org 0:5e1631496985 159 /** 1: this area is used; 0: this area is unused */
root@mbed.org 0:5e1631496985 160 u8_t used;
root@mbed.org 0:5e1631496985 161 };
root@mbed.org 0:5e1631496985 162
root@mbed.org 0:5e1631496985 163 /** All allocated blocks will be MIN_SIZE bytes big, at least!
root@mbed.org 0:5e1631496985 164 * MIN_SIZE can be overridden to suit your needs. Smaller values save space,
root@mbed.org 0:5e1631496985 165 * larger values could prevent too small blocks to fragment the RAM too much. */
root@mbed.org 0:5e1631496985 166 #ifndef MIN_SIZE
root@mbed.org 0:5e1631496985 167 #define MIN_SIZE 12
root@mbed.org 0:5e1631496985 168 #endif /* MIN_SIZE */
root@mbed.org 0:5e1631496985 169 /* some alignment macros: we define them here for better source code layout */
root@mbed.org 0:5e1631496985 170 #define MIN_SIZE_ALIGNED LWIP_MEM_ALIGN_SIZE(MIN_SIZE)
root@mbed.org 0:5e1631496985 171 #define SIZEOF_STRUCT_MEM LWIP_MEM_ALIGN_SIZE(sizeof(struct mem))
root@mbed.org 0:5e1631496985 172 #define MEM_SIZE_ALIGNED LWIP_MEM_ALIGN_SIZE(MEM_SIZE)
root@mbed.org 0:5e1631496985 173
root@mbed.org 0:5e1631496985 174 /** the heap. we need one struct mem at the end and some room for alignment */
root@mbed.org 0:5e1631496985 175 static u8_t ram_heap[MEM_SIZE_ALIGNED + (2*SIZEOF_STRUCT_MEM) + MEM_ALIGNMENT] MEM_POSITION;
root@mbed.org 0:5e1631496985 176 /** pointer to the heap (ram_heap): for alignment, ram is now a pointer instead of an array */
root@mbed.org 0:5e1631496985 177 static u8_t *ram;
root@mbed.org 0:5e1631496985 178 /** the last entry, always unused! */
root@mbed.org 0:5e1631496985 179 static struct mem *ram_end;
root@mbed.org 0:5e1631496985 180 /** pointer to the lowest free block, this is used for faster search */
root@mbed.org 0:5e1631496985 181 static struct mem *lfree;
root@mbed.org 0:5e1631496985 182
root@mbed.org 0:5e1631496985 183 /** concurrent access protection */
root@mbed.org 0:5e1631496985 184 static sys_sem_t mem_sem;
root@mbed.org 0:5e1631496985 185
root@mbed.org 0:5e1631496985 186 #if LWIP_ALLOW_MEM_FREE_FROM_OTHER_CONTEXT
root@mbed.org 0:5e1631496985 187
root@mbed.org 0:5e1631496985 188 static volatile u8_t mem_free_count;
root@mbed.org 0:5e1631496985 189
root@mbed.org 0:5e1631496985 190 /* Allow mem_free from other (e.g. interrupt) context */
root@mbed.org 0:5e1631496985 191 #define LWIP_MEM_FREE_DECL_PROTECT() SYS_ARCH_DECL_PROTECT(lev_free)
root@mbed.org 0:5e1631496985 192 #define LWIP_MEM_FREE_PROTECT() SYS_ARCH_PROTECT(lev_free)
root@mbed.org 0:5e1631496985 193 #define LWIP_MEM_FREE_UNPROTECT() SYS_ARCH_UNPROTECT(lev_free)
root@mbed.org 0:5e1631496985 194 #define LWIP_MEM_ALLOC_DECL_PROTECT() SYS_ARCH_DECL_PROTECT(lev_alloc)
root@mbed.org 0:5e1631496985 195 #define LWIP_MEM_ALLOC_PROTECT() SYS_ARCH_PROTECT(lev_alloc)
root@mbed.org 0:5e1631496985 196 #define LWIP_MEM_ALLOC_UNPROTECT() SYS_ARCH_UNPROTECT(lev_alloc)
root@mbed.org 0:5e1631496985 197
root@mbed.org 0:5e1631496985 198 #else /* LWIP_ALLOW_MEM_FREE_FROM_OTHER_CONTEXT */
root@mbed.org 0:5e1631496985 199
root@mbed.org 0:5e1631496985 200 /* Protect the heap only by using a semaphore */
root@mbed.org 0:5e1631496985 201 #define LWIP_MEM_FREE_DECL_PROTECT()
root@mbed.org 0:5e1631496985 202 #define LWIP_MEM_FREE_PROTECT() sys_arch_sem_wait(mem_sem, 0)
root@mbed.org 0:5e1631496985 203 #define LWIP_MEM_FREE_UNPROTECT() sys_sem_signal(mem_sem)
root@mbed.org 0:5e1631496985 204 /* mem_malloc is protected using semaphore AND LWIP_MEM_ALLOC_PROTECT */
root@mbed.org 0:5e1631496985 205 #define LWIP_MEM_ALLOC_DECL_PROTECT()
root@mbed.org 0:5e1631496985 206 #define LWIP_MEM_ALLOC_PROTECT()
root@mbed.org 0:5e1631496985 207 #define LWIP_MEM_ALLOC_UNPROTECT()
root@mbed.org 0:5e1631496985 208
root@mbed.org 0:5e1631496985 209 #endif /* LWIP_ALLOW_MEM_FREE_FROM_OTHER_CONTEXT */
root@mbed.org 0:5e1631496985 210
root@mbed.org 0:5e1631496985 211
root@mbed.org 0:5e1631496985 212 /**
root@mbed.org 0:5e1631496985 213 * "Plug holes" by combining adjacent empty struct mems.
root@mbed.org 0:5e1631496985 214 * After this function is through, there should not exist
root@mbed.org 0:5e1631496985 215 * one empty struct mem pointing to another empty struct mem.
root@mbed.org 0:5e1631496985 216 *
root@mbed.org 0:5e1631496985 217 * @param mem this points to a struct mem which just has been freed
root@mbed.org 0:5e1631496985 218 * @internal this function is only called by mem_free() and mem_realloc()
root@mbed.org 0:5e1631496985 219 *
root@mbed.org 0:5e1631496985 220 * This assumes access to the heap is protected by the calling function
root@mbed.org 0:5e1631496985 221 * already.
root@mbed.org 0:5e1631496985 222 */
root@mbed.org 0:5e1631496985 223 static void
root@mbed.org 0:5e1631496985 224 plug_holes(struct mem *mem)
root@mbed.org 0:5e1631496985 225 {
root@mbed.org 0:5e1631496985 226 struct mem *nmem;
root@mbed.org 0:5e1631496985 227 struct mem *pmem;
root@mbed.org 0:5e1631496985 228
root@mbed.org 0:5e1631496985 229 LWIP_ASSERT("plug_holes: mem >= ram", (u8_t *)mem >= ram);
root@mbed.org 0:5e1631496985 230 LWIP_ASSERT("plug_holes: mem < ram_end", (u8_t *)mem < (u8_t *)ram_end);
root@mbed.org 0:5e1631496985 231 LWIP_ASSERT("plug_holes: mem->used == 0", mem->used == 0);
root@mbed.org 0:5e1631496985 232
root@mbed.org 0:5e1631496985 233 /* plug hole forward */
root@mbed.org 0:5e1631496985 234 LWIP_ASSERT("plug_holes: mem->next <= MEM_SIZE_ALIGNED", mem->next <= MEM_SIZE_ALIGNED);
root@mbed.org 0:5e1631496985 235
root@mbed.org 0:5e1631496985 236 nmem = (struct mem *)&ram[mem->next];
root@mbed.org 0:5e1631496985 237 if (mem != nmem && nmem->used == 0 && (u8_t *)nmem != (u8_t *)ram_end) {
root@mbed.org 0:5e1631496985 238 /* if mem->next is unused and not end of ram, combine mem and mem->next */
root@mbed.org 0:5e1631496985 239 if (lfree == nmem) {
root@mbed.org 0:5e1631496985 240 lfree = mem;
root@mbed.org 0:5e1631496985 241 }
root@mbed.org 0:5e1631496985 242 mem->next = nmem->next;
root@mbed.org 0:5e1631496985 243 ((struct mem *)&ram[nmem->next])->prev = (u8_t *)mem - ram;
root@mbed.org 0:5e1631496985 244 }
root@mbed.org 0:5e1631496985 245
root@mbed.org 0:5e1631496985 246 /* plug hole backward */
root@mbed.org 0:5e1631496985 247 pmem = (struct mem *)&ram[mem->prev];
root@mbed.org 0:5e1631496985 248 if (pmem != mem && pmem->used == 0) {
root@mbed.org 0:5e1631496985 249 /* if mem->prev is unused, combine mem and mem->prev */
root@mbed.org 0:5e1631496985 250 if (lfree == mem) {
root@mbed.org 0:5e1631496985 251 lfree = pmem;
root@mbed.org 0:5e1631496985 252 }
root@mbed.org 0:5e1631496985 253 pmem->next = mem->next;
root@mbed.org 0:5e1631496985 254 ((struct mem *)&ram[mem->next])->prev = (u8_t *)pmem - ram;
root@mbed.org 0:5e1631496985 255 }
root@mbed.org 0:5e1631496985 256 }
root@mbed.org 0:5e1631496985 257
root@mbed.org 0:5e1631496985 258 /**
root@mbed.org 0:5e1631496985 259 * Zero the heap and initialize start, end and lowest-free
root@mbed.org 0:5e1631496985 260 */
root@mbed.org 0:5e1631496985 261 void
root@mbed.org 0:5e1631496985 262 mem_init(void)
root@mbed.org 0:5e1631496985 263 {
root@mbed.org 0:5e1631496985 264 struct mem *mem;
root@mbed.org 0:5e1631496985 265
root@mbed.org 0:5e1631496985 266 LWIP_ASSERT("Sanity check alignment",
root@mbed.org 0:5e1631496985 267 (SIZEOF_STRUCT_MEM & (MEM_ALIGNMENT-1)) == 0);
root@mbed.org 0:5e1631496985 268
root@mbed.org 0:5e1631496985 269 /* align the heap */
root@mbed.org 0:5e1631496985 270 ram = (u8_t *) LWIP_MEM_ALIGN(ram_heap);
root@mbed.org 0:5e1631496985 271 /* initialize the start of the heap */
root@mbed.org 0:5e1631496985 272 mem = (struct mem *)ram;
root@mbed.org 0:5e1631496985 273 mem->next = MEM_SIZE_ALIGNED;
root@mbed.org 0:5e1631496985 274 mem->prev = 0;
root@mbed.org 0:5e1631496985 275 mem->used = 0;
root@mbed.org 0:5e1631496985 276 /* initialize the end of the heap */
root@mbed.org 0:5e1631496985 277 ram_end = (struct mem *)&ram[MEM_SIZE_ALIGNED];
root@mbed.org 0:5e1631496985 278 ram_end->used = 1;
root@mbed.org 0:5e1631496985 279 ram_end->next = MEM_SIZE_ALIGNED;
root@mbed.org 0:5e1631496985 280 ram_end->prev = MEM_SIZE_ALIGNED;
root@mbed.org 0:5e1631496985 281
root@mbed.org 0:5e1631496985 282 mem_sem = sys_sem_new(1);
root@mbed.org 0:5e1631496985 283
root@mbed.org 0:5e1631496985 284 /* initialize the lowest-free pointer to the start of the heap */
root@mbed.org 0:5e1631496985 285 lfree = (struct mem *)ram;
root@mbed.org 0:5e1631496985 286
root@mbed.org 0:5e1631496985 287 MEM_STATS_AVAIL(avail, MEM_SIZE_ALIGNED);
root@mbed.org 0:5e1631496985 288 }
root@mbed.org 0:5e1631496985 289
root@mbed.org 0:5e1631496985 290 /**
root@mbed.org 0:5e1631496985 291 * Put a struct mem back on the heap
root@mbed.org 0:5e1631496985 292 *
root@mbed.org 0:5e1631496985 293 * @param rmem is the data portion of a struct mem as returned by a previous
root@mbed.org 0:5e1631496985 294 * call to mem_malloc()
root@mbed.org 0:5e1631496985 295 */
root@mbed.org 0:5e1631496985 296 void
root@mbed.org 0:5e1631496985 297 mem_free(void *rmem)
root@mbed.org 0:5e1631496985 298 {
root@mbed.org 0:5e1631496985 299 struct mem *mem;
root@mbed.org 0:5e1631496985 300 LWIP_MEM_FREE_DECL_PROTECT();
root@mbed.org 0:5e1631496985 301
root@mbed.org 0:5e1631496985 302 if (rmem == NULL) {
root@mbed.org 0:5e1631496985 303 LWIP_DEBUGF(MEM_DEBUG | LWIP_DBG_TRACE | 2, ("mem_free(p == NULL) was called.\n"));
root@mbed.org 0:5e1631496985 304 return;
root@mbed.org 0:5e1631496985 305 }
root@mbed.org 0:5e1631496985 306 LWIP_ASSERT("mem_free: sanity check alignment", (((mem_ptr_t)rmem) & (MEM_ALIGNMENT-1)) == 0);
root@mbed.org 0:5e1631496985 307
root@mbed.org 0:5e1631496985 308 LWIP_ASSERT("mem_free: legal memory", (u8_t *)rmem >= (u8_t *)ram &&
root@mbed.org 0:5e1631496985 309 (u8_t *)rmem < (u8_t *)ram_end);
root@mbed.org 0:5e1631496985 310
root@mbed.org 0:5e1631496985 311 if ((u8_t *)rmem < (u8_t *)ram || (u8_t *)rmem >= (u8_t *)ram_end) {
root@mbed.org 0:5e1631496985 312 SYS_ARCH_DECL_PROTECT(lev);
root@mbed.org 0:5e1631496985 313 LWIP_DEBUGF(MEM_DEBUG | 3, ("mem_free: illegal memory\n"));
root@mbed.org 0:5e1631496985 314 /* protect mem stats from concurrent access */
root@mbed.org 0:5e1631496985 315 SYS_ARCH_PROTECT(lev);
root@mbed.org 0:5e1631496985 316 MEM_STATS_INC(illegal);
root@mbed.org 0:5e1631496985 317 SYS_ARCH_UNPROTECT(lev);
root@mbed.org 0:5e1631496985 318 return;
root@mbed.org 0:5e1631496985 319 }
root@mbed.org 0:5e1631496985 320 /* protect the heap from concurrent access */
root@mbed.org 0:5e1631496985 321 LWIP_MEM_FREE_PROTECT();
root@mbed.org 0:5e1631496985 322 /* Get the corresponding struct mem ... */
root@mbed.org 0:5e1631496985 323 mem = (struct mem *)((u8_t *)rmem - SIZEOF_STRUCT_MEM);
root@mbed.org 0:5e1631496985 324 /* ... which has to be in a used state ... */
root@mbed.org 0:5e1631496985 325 LWIP_ASSERT("mem_free: mem->used", mem->used);
root@mbed.org 0:5e1631496985 326 /* ... and is now unused. */
root@mbed.org 0:5e1631496985 327 mem->used = 0;
root@mbed.org 0:5e1631496985 328
root@mbed.org 0:5e1631496985 329 if (mem < lfree) {
root@mbed.org 0:5e1631496985 330 /* the newly freed struct is now the lowest */
root@mbed.org 0:5e1631496985 331 lfree = mem;
root@mbed.org 0:5e1631496985 332 }
root@mbed.org 0:5e1631496985 333
root@mbed.org 0:5e1631496985 334 MEM_STATS_DEC_USED(used, mem->next - ((u8_t *)mem - ram));
root@mbed.org 0:5e1631496985 335
root@mbed.org 0:5e1631496985 336 /* finally, see if prev or next are free also */
root@mbed.org 0:5e1631496985 337 plug_holes(mem);
root@mbed.org 0:5e1631496985 338 #if LWIP_ALLOW_MEM_FREE_FROM_OTHER_CONTEXT
root@mbed.org 0:5e1631496985 339 mem_free_count = 1;
root@mbed.org 0:5e1631496985 340 #endif /* LWIP_ALLOW_MEM_FREE_FROM_OTHER_CONTEXT */
root@mbed.org 0:5e1631496985 341 LWIP_MEM_FREE_UNPROTECT();
root@mbed.org 0:5e1631496985 342 }
root@mbed.org 0:5e1631496985 343
root@mbed.org 0:5e1631496985 344 /**
root@mbed.org 0:5e1631496985 345 * In contrast to its name, mem_realloc can only shrink memory, not expand it.
root@mbed.org 0:5e1631496985 346 * Since the only use (for now) is in pbuf_realloc (which also can only shrink),
root@mbed.org 0:5e1631496985 347 * this shouldn't be a problem!
root@mbed.org 0:5e1631496985 348 *
root@mbed.org 0:5e1631496985 349 * @param rmem pointer to memory allocated by mem_malloc the is to be shrinked
root@mbed.org 0:5e1631496985 350 * @param newsize required size after shrinking (needs to be smaller than or
root@mbed.org 0:5e1631496985 351 * equal to the previous size)
root@mbed.org 0:5e1631496985 352 * @return for compatibility reasons: is always == rmem, at the moment
root@mbed.org 0:5e1631496985 353 * or NULL if newsize is > old size, in which case rmem is NOT touched
root@mbed.org 0:5e1631496985 354 * or freed!
root@mbed.org 0:5e1631496985 355 */
root@mbed.org 0:5e1631496985 356 void *
root@mbed.org 0:5e1631496985 357 mem_realloc(void *rmem, mem_size_t newsize)
root@mbed.org 0:5e1631496985 358 {
root@mbed.org 0:5e1631496985 359 mem_size_t size;
root@mbed.org 0:5e1631496985 360 mem_size_t ptr, ptr2;
root@mbed.org 0:5e1631496985 361 struct mem *mem, *mem2;
root@mbed.org 0:5e1631496985 362 /* use the FREE_PROTECT here: it protects with sem OR SYS_ARCH_PROTECT */
root@mbed.org 0:5e1631496985 363 LWIP_MEM_FREE_DECL_PROTECT();
root@mbed.org 0:5e1631496985 364
root@mbed.org 0:5e1631496985 365 /* Expand the size of the allocated memory region so that we can
root@mbed.org 0:5e1631496985 366 adjust for alignment. */
root@mbed.org 0:5e1631496985 367 newsize = LWIP_MEM_ALIGN_SIZE(newsize);
root@mbed.org 0:5e1631496985 368
root@mbed.org 0:5e1631496985 369 if(newsize < MIN_SIZE_ALIGNED) {
root@mbed.org 0:5e1631496985 370 /* every data block must be at least MIN_SIZE_ALIGNED long */
root@mbed.org 0:5e1631496985 371 newsize = MIN_SIZE_ALIGNED;
root@mbed.org 0:5e1631496985 372 }
root@mbed.org 0:5e1631496985 373
root@mbed.org 0:5e1631496985 374 if (newsize > MEM_SIZE_ALIGNED) {
root@mbed.org 0:5e1631496985 375 return NULL;
root@mbed.org 0:5e1631496985 376 }
root@mbed.org 0:5e1631496985 377
root@mbed.org 0:5e1631496985 378 LWIP_ASSERT("mem_realloc: legal memory", (u8_t *)rmem >= (u8_t *)ram &&
root@mbed.org 0:5e1631496985 379 (u8_t *)rmem < (u8_t *)ram_end);
root@mbed.org 0:5e1631496985 380
root@mbed.org 0:5e1631496985 381 if ((u8_t *)rmem < (u8_t *)ram || (u8_t *)rmem >= (u8_t *)ram_end) {
root@mbed.org 0:5e1631496985 382 SYS_ARCH_DECL_PROTECT(lev);
root@mbed.org 0:5e1631496985 383 LWIP_DEBUGF(MEM_DEBUG | 3, ("mem_realloc: illegal memory\n"));
root@mbed.org 0:5e1631496985 384 /* protect mem stats from concurrent access */
root@mbed.org 0:5e1631496985 385 SYS_ARCH_PROTECT(lev);
root@mbed.org 0:5e1631496985 386 MEM_STATS_INC(illegal);
root@mbed.org 0:5e1631496985 387 SYS_ARCH_UNPROTECT(lev);
root@mbed.org 0:5e1631496985 388 return rmem;
root@mbed.org 0:5e1631496985 389 }
root@mbed.org 0:5e1631496985 390 /* Get the corresponding struct mem ... */
root@mbed.org 0:5e1631496985 391 mem = (struct mem *)((u8_t *)rmem - SIZEOF_STRUCT_MEM);
root@mbed.org 0:5e1631496985 392 /* ... and its offset pointer */
root@mbed.org 0:5e1631496985 393 ptr = (u8_t *)mem - ram;
root@mbed.org 0:5e1631496985 394
root@mbed.org 0:5e1631496985 395 size = mem->next - ptr - SIZEOF_STRUCT_MEM;
root@mbed.org 0:5e1631496985 396 LWIP_ASSERT("mem_realloc can only shrink memory", newsize <= size);
root@mbed.org 0:5e1631496985 397 if (newsize > size) {
root@mbed.org 0:5e1631496985 398 /* not supported */
root@mbed.org 0:5e1631496985 399 return NULL;
root@mbed.org 0:5e1631496985 400 }
root@mbed.org 0:5e1631496985 401 if (newsize == size) {
root@mbed.org 0:5e1631496985 402 /* No change in size, simply return */
root@mbed.org 0:5e1631496985 403 return rmem;
root@mbed.org 0:5e1631496985 404 }
root@mbed.org 0:5e1631496985 405
root@mbed.org 0:5e1631496985 406 /* protect the heap from concurrent access */
root@mbed.org 0:5e1631496985 407 LWIP_MEM_FREE_PROTECT();
root@mbed.org 0:5e1631496985 408
root@mbed.org 0:5e1631496985 409 MEM_STATS_DEC_USED(used, (size - newsize));
root@mbed.org 0:5e1631496985 410
root@mbed.org 0:5e1631496985 411 mem2 = (struct mem *)&ram[mem->next];
root@mbed.org 0:5e1631496985 412 if(mem2->used == 0) {
root@mbed.org 0:5e1631496985 413 /* The next struct is unused, we can simply move it at little */
root@mbed.org 0:5e1631496985 414 mem_size_t next;
root@mbed.org 0:5e1631496985 415 /* remember the old next pointer */
root@mbed.org 0:5e1631496985 416 next = mem2->next;
root@mbed.org 0:5e1631496985 417 /* create new struct mem which is moved directly after the shrinked mem */
root@mbed.org 0:5e1631496985 418 ptr2 = ptr + SIZEOF_STRUCT_MEM + newsize;
root@mbed.org 0:5e1631496985 419 if (lfree == mem2) {
root@mbed.org 0:5e1631496985 420 lfree = (struct mem *)&ram[ptr2];
root@mbed.org 0:5e1631496985 421 }
root@mbed.org 0:5e1631496985 422 mem2 = (struct mem *)&ram[ptr2];
root@mbed.org 0:5e1631496985 423 mem2->used = 0;
root@mbed.org 0:5e1631496985 424 /* restore the next pointer */
root@mbed.org 0:5e1631496985 425 mem2->next = next;
root@mbed.org 0:5e1631496985 426 /* link it back to mem */
root@mbed.org 0:5e1631496985 427 mem2->prev = ptr;
root@mbed.org 0:5e1631496985 428 /* link mem to it */
root@mbed.org 0:5e1631496985 429 mem->next = ptr2;
root@mbed.org 0:5e1631496985 430 /* last thing to restore linked list: as we have moved mem2,
root@mbed.org 0:5e1631496985 431 * let 'mem2->next->prev' point to mem2 again. but only if mem2->next is not
root@mbed.org 0:5e1631496985 432 * the end of the heap */
root@mbed.org 0:5e1631496985 433 if (mem2->next != MEM_SIZE_ALIGNED) {
root@mbed.org 0:5e1631496985 434 ((struct mem *)&ram[mem2->next])->prev = ptr2;
root@mbed.org 0:5e1631496985 435 }
root@mbed.org 0:5e1631496985 436 /* no need to plug holes, we've already done that */
root@mbed.org 0:5e1631496985 437 } else if (newsize + SIZEOF_STRUCT_MEM + MIN_SIZE_ALIGNED <= size) {
root@mbed.org 0:5e1631496985 438 /* Next struct is used but there's room for another struct mem with
root@mbed.org 0:5e1631496985 439 * at least MIN_SIZE_ALIGNED of data.
root@mbed.org 0:5e1631496985 440 * Old size ('size') must be big enough to contain at least 'newsize' plus a struct mem
root@mbed.org 0:5e1631496985 441 * ('SIZEOF_STRUCT_MEM') with some data ('MIN_SIZE_ALIGNED').
root@mbed.org 0:5e1631496985 442 * @todo we could leave out MIN_SIZE_ALIGNED. We would create an empty
root@mbed.org 0:5e1631496985 443 * region that couldn't hold data, but when mem->next gets freed,
root@mbed.org 0:5e1631496985 444 * the 2 regions would be combined, resulting in more free memory */
root@mbed.org 0:5e1631496985 445 ptr2 = ptr + SIZEOF_STRUCT_MEM + newsize;
root@mbed.org 0:5e1631496985 446 mem2 = (struct mem *)&ram[ptr2];
root@mbed.org 0:5e1631496985 447 if (mem2 < lfree) {
root@mbed.org 0:5e1631496985 448 lfree = mem2;
root@mbed.org 0:5e1631496985 449 }
root@mbed.org 0:5e1631496985 450 mem2->used = 0;
root@mbed.org 0:5e1631496985 451 mem2->next = mem->next;
root@mbed.org 0:5e1631496985 452 mem2->prev = ptr;
root@mbed.org 0:5e1631496985 453 mem->next = ptr2;
root@mbed.org 0:5e1631496985 454 if (mem2->next != MEM_SIZE_ALIGNED) {
root@mbed.org 0:5e1631496985 455 ((struct mem *)&ram[mem2->next])->prev = ptr2;
root@mbed.org 0:5e1631496985 456 }
root@mbed.org 0:5e1631496985 457 /* the original mem->next is used, so no need to plug holes! */
root@mbed.org 0:5e1631496985 458 }
root@mbed.org 0:5e1631496985 459 /* else {
root@mbed.org 0:5e1631496985 460 next struct mem is used but size between mem and mem2 is not big enough
root@mbed.org 0:5e1631496985 461 to create another struct mem
root@mbed.org 0:5e1631496985 462 -> don't do anyhting.
root@mbed.org 0:5e1631496985 463 -> the remaining space stays unused since it is too small
root@mbed.org 0:5e1631496985 464 } */
root@mbed.org 0:5e1631496985 465 #if LWIP_ALLOW_MEM_FREE_FROM_OTHER_CONTEXT
root@mbed.org 0:5e1631496985 466 mem_free_count = 1;
root@mbed.org 0:5e1631496985 467 #endif /* LWIP_ALLOW_MEM_FREE_FROM_OTHER_CONTEXT */
root@mbed.org 0:5e1631496985 468 LWIP_MEM_FREE_UNPROTECT();
root@mbed.org 0:5e1631496985 469 return rmem;
root@mbed.org 0:5e1631496985 470 }
root@mbed.org 0:5e1631496985 471
root@mbed.org 0:5e1631496985 472 /**
root@mbed.org 0:5e1631496985 473 * Adam's mem_malloc() plus solution for bug #17922
root@mbed.org 0:5e1631496985 474 * Allocate a block of memory with a minimum of 'size' bytes.
root@mbed.org 0:5e1631496985 475 *
root@mbed.org 0:5e1631496985 476 * @param size is the minimum size of the requested block in bytes.
root@mbed.org 0:5e1631496985 477 * @return pointer to allocated memory or NULL if no free memory was found.
root@mbed.org 0:5e1631496985 478 *
root@mbed.org 0:5e1631496985 479 * Note that the returned value will always be aligned (as defined by MEM_ALIGNMENT).
root@mbed.org 0:5e1631496985 480 */
root@mbed.org 0:5e1631496985 481 void *
root@mbed.org 0:5e1631496985 482 mem_malloc(mem_size_t size)
root@mbed.org 0:5e1631496985 483 {
root@mbed.org 0:5e1631496985 484 mem_size_t ptr, ptr2;
root@mbed.org 0:5e1631496985 485 struct mem *mem, *mem2;
root@mbed.org 0:5e1631496985 486 #if LWIP_ALLOW_MEM_FREE_FROM_OTHER_CONTEXT
root@mbed.org 0:5e1631496985 487 u8_t local_mem_free_count = 0;
root@mbed.org 0:5e1631496985 488 #endif /* LWIP_ALLOW_MEM_FREE_FROM_OTHER_CONTEXT */
root@mbed.org 0:5e1631496985 489 LWIP_MEM_ALLOC_DECL_PROTECT();
root@mbed.org 0:5e1631496985 490
root@mbed.org 0:5e1631496985 491 if (size == 0) {
root@mbed.org 0:5e1631496985 492 return NULL;
root@mbed.org 0:5e1631496985 493 }
root@mbed.org 0:5e1631496985 494
root@mbed.org 0:5e1631496985 495 /* Expand the size of the allocated memory region so that we can
root@mbed.org 0:5e1631496985 496 adjust for alignment. */
root@mbed.org 0:5e1631496985 497 size = LWIP_MEM_ALIGN_SIZE(size);
root@mbed.org 0:5e1631496985 498
root@mbed.org 0:5e1631496985 499 if(size < MIN_SIZE_ALIGNED) {
root@mbed.org 0:5e1631496985 500 /* every data block must be at least MIN_SIZE_ALIGNED long */
root@mbed.org 0:5e1631496985 501 size = MIN_SIZE_ALIGNED;
root@mbed.org 0:5e1631496985 502 }
root@mbed.org 0:5e1631496985 503
root@mbed.org 0:5e1631496985 504 if (size > MEM_SIZE_ALIGNED) {
root@mbed.org 0:5e1631496985 505 return NULL;
root@mbed.org 0:5e1631496985 506 }
root@mbed.org 0:5e1631496985 507
root@mbed.org 0:5e1631496985 508 /* protect the heap from concurrent access */
root@mbed.org 0:5e1631496985 509 sys_arch_sem_wait(mem_sem, 0);
root@mbed.org 0:5e1631496985 510 LWIP_MEM_ALLOC_PROTECT();
root@mbed.org 0:5e1631496985 511 #if LWIP_ALLOW_MEM_FREE_FROM_OTHER_CONTEXT
root@mbed.org 0:5e1631496985 512 /* run as long as a mem_free disturbed mem_malloc */
root@mbed.org 0:5e1631496985 513 do {
root@mbed.org 0:5e1631496985 514 local_mem_free_count = 0;
root@mbed.org 0:5e1631496985 515 #endif /* LWIP_ALLOW_MEM_FREE_FROM_OTHER_CONTEXT */
root@mbed.org 0:5e1631496985 516
root@mbed.org 0:5e1631496985 517 /* Scan through the heap searching for a free block that is big enough,
root@mbed.org 0:5e1631496985 518 * beginning with the lowest free block.
root@mbed.org 0:5e1631496985 519 */
root@mbed.org 0:5e1631496985 520 for (ptr = (u8_t *)lfree - ram; ptr < MEM_SIZE_ALIGNED - size;
root@mbed.org 0:5e1631496985 521 ptr = ((struct mem *)&ram[ptr])->next) {
root@mbed.org 0:5e1631496985 522 mem = (struct mem *)&ram[ptr];
root@mbed.org 0:5e1631496985 523 #if LWIP_ALLOW_MEM_FREE_FROM_OTHER_CONTEXT
root@mbed.org 0:5e1631496985 524 mem_free_count = 0;
root@mbed.org 0:5e1631496985 525 LWIP_MEM_ALLOC_UNPROTECT();
root@mbed.org 0:5e1631496985 526 /* allow mem_free to run */
root@mbed.org 0:5e1631496985 527 LWIP_MEM_ALLOC_PROTECT();
root@mbed.org 0:5e1631496985 528 if (mem_free_count != 0) {
root@mbed.org 0:5e1631496985 529 local_mem_free_count = mem_free_count;
root@mbed.org 0:5e1631496985 530 }
root@mbed.org 0:5e1631496985 531 mem_free_count = 0;
root@mbed.org 0:5e1631496985 532 #endif /* LWIP_ALLOW_MEM_FREE_FROM_OTHER_CONTEXT */
root@mbed.org 0:5e1631496985 533
root@mbed.org 0:5e1631496985 534 if ((!mem->used) &&
root@mbed.org 0:5e1631496985 535 (mem->next - (ptr + SIZEOF_STRUCT_MEM)) >= size) {
root@mbed.org 0:5e1631496985 536 /* mem is not used and at least perfect fit is possible:
root@mbed.org 0:5e1631496985 537 * mem->next - (ptr + SIZEOF_STRUCT_MEM) gives us the 'user data size' of mem */
root@mbed.org 0:5e1631496985 538
root@mbed.org 0:5e1631496985 539 if (mem->next - (ptr + SIZEOF_STRUCT_MEM) >= (size + SIZEOF_STRUCT_MEM + MIN_SIZE_ALIGNED)) {
root@mbed.org 0:5e1631496985 540 /* (in addition to the above, we test if another struct mem (SIZEOF_STRUCT_MEM) containing
root@mbed.org 0:5e1631496985 541 * at least MIN_SIZE_ALIGNED of data also fits in the 'user data space' of 'mem')
root@mbed.org 0:5e1631496985 542 * -> split large block, create empty remainder,
root@mbed.org 0:5e1631496985 543 * remainder must be large enough to contain MIN_SIZE_ALIGNED data: if
root@mbed.org 0:5e1631496985 544 * mem->next - (ptr + (2*SIZEOF_STRUCT_MEM)) == size,
root@mbed.org 0:5e1631496985 545 * struct mem would fit in but no data between mem2 and mem2->next
root@mbed.org 0:5e1631496985 546 * @todo we could leave out MIN_SIZE_ALIGNED. We would create an empty
root@mbed.org 0:5e1631496985 547 * region that couldn't hold data, but when mem->next gets freed,
root@mbed.org 0:5e1631496985 548 * the 2 regions would be combined, resulting in more free memory
root@mbed.org 0:5e1631496985 549 */
root@mbed.org 0:5e1631496985 550 ptr2 = ptr + SIZEOF_STRUCT_MEM + size;
root@mbed.org 0:5e1631496985 551 /* create mem2 struct */
root@mbed.org 0:5e1631496985 552 mem2 = (struct mem *)&ram[ptr2];
root@mbed.org 0:5e1631496985 553 mem2->used = 0;
root@mbed.org 0:5e1631496985 554 mem2->next = mem->next;
root@mbed.org 0:5e1631496985 555 mem2->prev = ptr;
root@mbed.org 0:5e1631496985 556 /* and insert it between mem and mem->next */
root@mbed.org 0:5e1631496985 557 mem->next = ptr2;
root@mbed.org 0:5e1631496985 558 mem->used = 1;
root@mbed.org 0:5e1631496985 559
root@mbed.org 0:5e1631496985 560 if (mem2->next != MEM_SIZE_ALIGNED) {
root@mbed.org 0:5e1631496985 561 ((struct mem *)&ram[mem2->next])->prev = ptr2;
root@mbed.org 0:5e1631496985 562 }
root@mbed.org 0:5e1631496985 563 MEM_STATS_INC_USED(used, (size + SIZEOF_STRUCT_MEM));
root@mbed.org 0:5e1631496985 564 } else {
root@mbed.org 0:5e1631496985 565 /* (a mem2 struct does no fit into the user data space of mem and mem->next will always
root@mbed.org 0:5e1631496985 566 * be used at this point: if not we have 2 unused structs in a row, plug_holes should have
root@mbed.org 0:5e1631496985 567 * take care of this).
root@mbed.org 0:5e1631496985 568 * -> near fit or excact fit: do not split, no mem2 creation
root@mbed.org 0:5e1631496985 569 * also can't move mem->next directly behind mem, since mem->next
root@mbed.org 0:5e1631496985 570 * will always be used at this point!
root@mbed.org 0:5e1631496985 571 */
root@mbed.org 0:5e1631496985 572 mem->used = 1;
root@mbed.org 0:5e1631496985 573 MEM_STATS_INC_USED(used, mem->next - ((u8_t *)mem - ram));
root@mbed.org 0:5e1631496985 574 }
root@mbed.org 0:5e1631496985 575
root@mbed.org 0:5e1631496985 576 if (mem == lfree) {
root@mbed.org 0:5e1631496985 577 /* Find next free block after mem and update lowest free pointer */
root@mbed.org 0:5e1631496985 578 while (lfree->used && lfree != ram_end) {
root@mbed.org 0:5e1631496985 579 LWIP_MEM_ALLOC_UNPROTECT();
root@mbed.org 0:5e1631496985 580 /* prevent high interrupt latency... */
root@mbed.org 0:5e1631496985 581 LWIP_MEM_ALLOC_PROTECT();
root@mbed.org 0:5e1631496985 582 lfree = (struct mem *)&ram[lfree->next];
root@mbed.org 0:5e1631496985 583 }
root@mbed.org 0:5e1631496985 584 LWIP_ASSERT("mem_malloc: !lfree->used", ((lfree == ram_end) || (!lfree->used)));
root@mbed.org 0:5e1631496985 585 }
root@mbed.org 0:5e1631496985 586 LWIP_MEM_ALLOC_UNPROTECT();
root@mbed.org 0:5e1631496985 587 sys_sem_signal(mem_sem);
root@mbed.org 0:5e1631496985 588 LWIP_ASSERT("mem_malloc: allocated memory not above ram_end.",
root@mbed.org 0:5e1631496985 589 (mem_ptr_t)mem + SIZEOF_STRUCT_MEM + size <= (mem_ptr_t)ram_end);
root@mbed.org 0:5e1631496985 590 LWIP_ASSERT("mem_malloc: allocated memory properly aligned.",
root@mbed.org 0:5e1631496985 591 ((mem_ptr_t)mem + SIZEOF_STRUCT_MEM) % MEM_ALIGNMENT == 0);
root@mbed.org 0:5e1631496985 592 LWIP_ASSERT("mem_malloc: sanity check alignment",
root@mbed.org 0:5e1631496985 593 (((mem_ptr_t)mem) & (MEM_ALIGNMENT-1)) == 0);
root@mbed.org 0:5e1631496985 594
root@mbed.org 0:5e1631496985 595 return (u8_t *)mem + SIZEOF_STRUCT_MEM;
root@mbed.org 0:5e1631496985 596 }
root@mbed.org 0:5e1631496985 597 }
root@mbed.org 0:5e1631496985 598 #if LWIP_ALLOW_MEM_FREE_FROM_OTHER_CONTEXT
root@mbed.org 0:5e1631496985 599 /* if we got interrupted by a mem_free, try again */
root@mbed.org 0:5e1631496985 600 } while(local_mem_free_count != 0);
root@mbed.org 0:5e1631496985 601 #endif /* LWIP_ALLOW_MEM_FREE_FROM_OTHER_CONTEXT */
root@mbed.org 0:5e1631496985 602 LWIP_DEBUGF(MEM_DEBUG | 2, ("mem_malloc: could not allocate %"S16_F" bytes\n", (s16_t)size));
root@mbed.org 0:5e1631496985 603 MEM_STATS_INC(err);
root@mbed.org 0:5e1631496985 604 LWIP_MEM_ALLOC_UNPROTECT();
root@mbed.org 0:5e1631496985 605 sys_sem_signal(mem_sem);
root@mbed.org 0:5e1631496985 606 return NULL;
root@mbed.org 0:5e1631496985 607 }
root@mbed.org 0:5e1631496985 608
root@mbed.org 0:5e1631496985 609 #endif /* MEM_USE_POOLS */
root@mbed.org 0:5e1631496985 610 /**
root@mbed.org 0:5e1631496985 611 * Contiguously allocates enough space for count objects that are size bytes
root@mbed.org 0:5e1631496985 612 * of memory each and returns a pointer to the allocated memory.
root@mbed.org 0:5e1631496985 613 *
root@mbed.org 0:5e1631496985 614 * The allocated memory is filled with bytes of value zero.
root@mbed.org 0:5e1631496985 615 *
root@mbed.org 0:5e1631496985 616 * @param count number of objects to allocate
root@mbed.org 0:5e1631496985 617 * @param size size of the objects to allocate
root@mbed.org 0:5e1631496985 618 * @return pointer to allocated memory / NULL pointer if there is an error
root@mbed.org 0:5e1631496985 619 */
root@mbed.org 0:5e1631496985 620 void *mem_calloc(mem_size_t count, mem_size_t size)
root@mbed.org 0:5e1631496985 621 {
root@mbed.org 0:5e1631496985 622 void *p;
root@mbed.org 0:5e1631496985 623
root@mbed.org 0:5e1631496985 624 /* allocate 'count' objects of size 'size' */
root@mbed.org 0:5e1631496985 625 p = mem_malloc(count * size);
root@mbed.org 0:5e1631496985 626 if (p) {
root@mbed.org 0:5e1631496985 627 /* zero the memory */
root@mbed.org 0:5e1631496985 628 memset(p, 0, count * size);
root@mbed.org 0:5e1631496985 629 }
root@mbed.org 0:5e1631496985 630 return p;
root@mbed.org 0:5e1631496985 631 }
root@mbed.org 0:5e1631496985 632
root@mbed.org 0:5e1631496985 633 #endif /* !MEM_LIBC_MALLOC */