Leest de waarde van een sensor binnen een maakt deze beschikbaar via internet

Dependencies:   NTPClient_NetServices mbed

Committer:
hendrikvincent
Date:
Mon Dec 02 09:01:23 2013 +0000
Revision:
0:05ccbd4f84f1
eerste programma;

Who changed what in which revision?

UserRevisionLine numberNew contents of line
hendrikvincent 0:05ccbd4f84f1 1 #pragma diag_remark 177
hendrikvincent 0:05ccbd4f84f1 2 /**
hendrikvincent 0:05ccbd4f84f1 3 * @file
hendrikvincent 0:05ccbd4f84f1 4 * Dynamic memory manager
hendrikvincent 0:05ccbd4f84f1 5 *
hendrikvincent 0:05ccbd4f84f1 6 * This is a lightweight replacement for the standard C library malloc().
hendrikvincent 0:05ccbd4f84f1 7 *
hendrikvincent 0:05ccbd4f84f1 8 * If you want to use the standard C library malloc() instead, define
hendrikvincent 0:05ccbd4f84f1 9 * MEM_LIBC_MALLOC to 1 in your lwipopts.h
hendrikvincent 0:05ccbd4f84f1 10 *
hendrikvincent 0:05ccbd4f84f1 11 * To let mem_malloc() use pools (prevents fragmentation and is much faster than
hendrikvincent 0:05ccbd4f84f1 12 * a heap but might waste some memory), define MEM_USE_POOLS to 1, define
hendrikvincent 0:05ccbd4f84f1 13 * MEM_USE_CUSTOM_POOLS to 1 and create a file "lwippools.h" that includes a list
hendrikvincent 0:05ccbd4f84f1 14 * of pools like this (more pools can be added between _START and _END):
hendrikvincent 0:05ccbd4f84f1 15 *
hendrikvincent 0:05ccbd4f84f1 16 * Define three pools with sizes 256, 512, and 1512 bytes
hendrikvincent 0:05ccbd4f84f1 17 * LWIP_MALLOC_MEMPOOL_START
hendrikvincent 0:05ccbd4f84f1 18 * LWIP_MALLOC_MEMPOOL(20, 256)
hendrikvincent 0:05ccbd4f84f1 19 * LWIP_MALLOC_MEMPOOL(10, 512)
hendrikvincent 0:05ccbd4f84f1 20 * LWIP_MALLOC_MEMPOOL(5, 1512)
hendrikvincent 0:05ccbd4f84f1 21 * LWIP_MALLOC_MEMPOOL_END
hendrikvincent 0:05ccbd4f84f1 22 */
hendrikvincent 0:05ccbd4f84f1 23
hendrikvincent 0:05ccbd4f84f1 24 /*
hendrikvincent 0:05ccbd4f84f1 25 * Copyright (c) 2001-2004 Swedish Institute of Computer Science.
hendrikvincent 0:05ccbd4f84f1 26 * All rights reserved.
hendrikvincent 0:05ccbd4f84f1 27 *
hendrikvincent 0:05ccbd4f84f1 28 * Redistribution and use in source and binary forms, with or without modification,
hendrikvincent 0:05ccbd4f84f1 29 * are permitted provided that the following conditions are met:
hendrikvincent 0:05ccbd4f84f1 30 *
hendrikvincent 0:05ccbd4f84f1 31 * 1. Redistributions of source code must retain the above copyright notice,
hendrikvincent 0:05ccbd4f84f1 32 * this list of conditions and the following disclaimer.
hendrikvincent 0:05ccbd4f84f1 33 * 2. Redistributions in binary form must reproduce the above copyright notice,
hendrikvincent 0:05ccbd4f84f1 34 * this list of conditions and the following disclaimer in the documentation
hendrikvincent 0:05ccbd4f84f1 35 * and/or other materials provided with the distribution.
hendrikvincent 0:05ccbd4f84f1 36 * 3. The name of the author may not be used to endorse or promote products
hendrikvincent 0:05ccbd4f84f1 37 * derived from this software without specific prior written permission.
hendrikvincent 0:05ccbd4f84f1 38 *
hendrikvincent 0:05ccbd4f84f1 39 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR IMPLIED
hendrikvincent 0:05ccbd4f84f1 40 * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
hendrikvincent 0:05ccbd4f84f1 41 * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT
hendrikvincent 0:05ccbd4f84f1 42 * SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
hendrikvincent 0:05ccbd4f84f1 43 * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT
hendrikvincent 0:05ccbd4f84f1 44 * OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
hendrikvincent 0:05ccbd4f84f1 45 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
hendrikvincent 0:05ccbd4f84f1 46 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
hendrikvincent 0:05ccbd4f84f1 47 * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY
hendrikvincent 0:05ccbd4f84f1 48 * OF SUCH DAMAGE.
hendrikvincent 0:05ccbd4f84f1 49 *
hendrikvincent 0:05ccbd4f84f1 50 * This file is part of the lwIP TCP/IP stack.
hendrikvincent 0:05ccbd4f84f1 51 *
hendrikvincent 0:05ccbd4f84f1 52 * Author: Adam Dunkels <adam@sics.se>
hendrikvincent 0:05ccbd4f84f1 53 * Simon Goldschmidt
hendrikvincent 0:05ccbd4f84f1 54 *
hendrikvincent 0:05ccbd4f84f1 55 */
hendrikvincent 0:05ccbd4f84f1 56
hendrikvincent 0:05ccbd4f84f1 57 #include "lwip/opt.h"
hendrikvincent 0:05ccbd4f84f1 58
hendrikvincent 0:05ccbd4f84f1 59 #if !MEM_LIBC_MALLOC /* don't build if not configured for use in lwipopts.h */
hendrikvincent 0:05ccbd4f84f1 60
hendrikvincent 0:05ccbd4f84f1 61 #include "lwip/def.h"
hendrikvincent 0:05ccbd4f84f1 62 #include "lwip/mem.h"
hendrikvincent 0:05ccbd4f84f1 63 #include "lwip/sys.h"
hendrikvincent 0:05ccbd4f84f1 64 #include "lwip/stats.h"
hendrikvincent 0:05ccbd4f84f1 65 #include "lwip/err.h"
hendrikvincent 0:05ccbd4f84f1 66
hendrikvincent 0:05ccbd4f84f1 67 #include <string.h>
hendrikvincent 0:05ccbd4f84f1 68
hendrikvincent 0:05ccbd4f84f1 69 #if MEM_USE_POOLS
hendrikvincent 0:05ccbd4f84f1 70 /* lwIP head implemented with different sized pools */
hendrikvincent 0:05ccbd4f84f1 71
hendrikvincent 0:05ccbd4f84f1 72 /**
hendrikvincent 0:05ccbd4f84f1 73 * Allocate memory: determine the smallest pool that is big enough
hendrikvincent 0:05ccbd4f84f1 74 * to contain an element of 'size' and get an element from that pool.
hendrikvincent 0:05ccbd4f84f1 75 *
hendrikvincent 0:05ccbd4f84f1 76 * @param size the size in bytes of the memory needed
hendrikvincent 0:05ccbd4f84f1 77 * @return a pointer to the allocated memory or NULL if the pool is empty
hendrikvincent 0:05ccbd4f84f1 78 */
hendrikvincent 0:05ccbd4f84f1 79 void *
hendrikvincent 0:05ccbd4f84f1 80 mem_malloc(mem_size_t size)
hendrikvincent 0:05ccbd4f84f1 81 {
hendrikvincent 0:05ccbd4f84f1 82 struct memp_malloc_helper *element;
hendrikvincent 0:05ccbd4f84f1 83 memp_t poolnr;
hendrikvincent 0:05ccbd4f84f1 84 mem_size_t required_size = size + sizeof(struct memp_malloc_helper);
hendrikvincent 0:05ccbd4f84f1 85
hendrikvincent 0:05ccbd4f84f1 86 for (poolnr = MEMP_POOL_FIRST; poolnr <= MEMP_POOL_LAST; poolnr = (memp_t)(poolnr + 1)) {
hendrikvincent 0:05ccbd4f84f1 87 #if MEM_USE_POOLS_TRY_BIGGER_POOL
hendrikvincent 0:05ccbd4f84f1 88 again:
hendrikvincent 0:05ccbd4f84f1 89 #endif /* MEM_USE_POOLS_TRY_BIGGER_POOL */
hendrikvincent 0:05ccbd4f84f1 90 /* is this pool big enough to hold an element of the required size
hendrikvincent 0:05ccbd4f84f1 91 plus a struct memp_malloc_helper that saves the pool this element came from? */
hendrikvincent 0:05ccbd4f84f1 92 if (required_size <= memp_sizes[poolnr]) {
hendrikvincent 0:05ccbd4f84f1 93 break;
hendrikvincent 0:05ccbd4f84f1 94 }
hendrikvincent 0:05ccbd4f84f1 95 }
hendrikvincent 0:05ccbd4f84f1 96 if (poolnr > MEMP_POOL_LAST) {
hendrikvincent 0:05ccbd4f84f1 97 LWIP_ASSERT("mem_malloc(): no pool is that big!", 0);
hendrikvincent 0:05ccbd4f84f1 98 return NULL;
hendrikvincent 0:05ccbd4f84f1 99 }
hendrikvincent 0:05ccbd4f84f1 100 element = (struct memp_malloc_helper*)memp_malloc(poolnr);
hendrikvincent 0:05ccbd4f84f1 101 if (element == NULL) {
hendrikvincent 0:05ccbd4f84f1 102 /* No need to DEBUGF or ASSERT: This error is already
hendrikvincent 0:05ccbd4f84f1 103 taken care of in memp.c */
hendrikvincent 0:05ccbd4f84f1 104 #if MEM_USE_POOLS_TRY_BIGGER_POOL
hendrikvincent 0:05ccbd4f84f1 105 /** Try a bigger pool if this one is empty! */
hendrikvincent 0:05ccbd4f84f1 106 if (poolnr < MEMP_POOL_LAST) {
hendrikvincent 0:05ccbd4f84f1 107 poolnr++;
hendrikvincent 0:05ccbd4f84f1 108 goto again;
hendrikvincent 0:05ccbd4f84f1 109 }
hendrikvincent 0:05ccbd4f84f1 110 #endif /* MEM_USE_POOLS_TRY_BIGGER_POOL */
hendrikvincent 0:05ccbd4f84f1 111 return NULL;
hendrikvincent 0:05ccbd4f84f1 112 }
hendrikvincent 0:05ccbd4f84f1 113
hendrikvincent 0:05ccbd4f84f1 114 /* save the pool number this element came from */
hendrikvincent 0:05ccbd4f84f1 115 element->poolnr = poolnr;
hendrikvincent 0:05ccbd4f84f1 116 /* and return a pointer to the memory directly after the struct memp_malloc_helper */
hendrikvincent 0:05ccbd4f84f1 117 element++;
hendrikvincent 0:05ccbd4f84f1 118
hendrikvincent 0:05ccbd4f84f1 119 return element;
hendrikvincent 0:05ccbd4f84f1 120 }
hendrikvincent 0:05ccbd4f84f1 121
hendrikvincent 0:05ccbd4f84f1 122 /**
hendrikvincent 0:05ccbd4f84f1 123 * Free memory previously allocated by mem_malloc. Loads the pool number
hendrikvincent 0:05ccbd4f84f1 124 * and calls memp_free with that pool number to put the element back into
hendrikvincent 0:05ccbd4f84f1 125 * its pool
hendrikvincent 0:05ccbd4f84f1 126 *
hendrikvincent 0:05ccbd4f84f1 127 * @param rmem the memory element to free
hendrikvincent 0:05ccbd4f84f1 128 */
hendrikvincent 0:05ccbd4f84f1 129 void
hendrikvincent 0:05ccbd4f84f1 130 mem_free(void *rmem)
hendrikvincent 0:05ccbd4f84f1 131 {
hendrikvincent 0:05ccbd4f84f1 132 struct memp_malloc_helper *hmem = (struct memp_malloc_helper*)rmem;
hendrikvincent 0:05ccbd4f84f1 133
hendrikvincent 0:05ccbd4f84f1 134 LWIP_ASSERT("rmem != NULL", (rmem != NULL));
hendrikvincent 0:05ccbd4f84f1 135 LWIP_ASSERT("rmem == MEM_ALIGN(rmem)", (rmem == LWIP_MEM_ALIGN(rmem)));
hendrikvincent 0:05ccbd4f84f1 136
hendrikvincent 0:05ccbd4f84f1 137 /* get the original struct memp_malloc_helper */
hendrikvincent 0:05ccbd4f84f1 138 hmem--;
hendrikvincent 0:05ccbd4f84f1 139
hendrikvincent 0:05ccbd4f84f1 140 LWIP_ASSERT("hmem != NULL", (hmem != NULL));
hendrikvincent 0:05ccbd4f84f1 141 LWIP_ASSERT("hmem == MEM_ALIGN(hmem)", (hmem == LWIP_MEM_ALIGN(hmem)));
hendrikvincent 0:05ccbd4f84f1 142 LWIP_ASSERT("hmem->poolnr < MEMP_MAX", (hmem->poolnr < MEMP_MAX));
hendrikvincent 0:05ccbd4f84f1 143
hendrikvincent 0:05ccbd4f84f1 144 /* and put it in the pool we saved earlier */
hendrikvincent 0:05ccbd4f84f1 145 memp_free(hmem->poolnr, hmem);
hendrikvincent 0:05ccbd4f84f1 146 }
hendrikvincent 0:05ccbd4f84f1 147
hendrikvincent 0:05ccbd4f84f1 148 #else /* MEM_USE_POOLS */
hendrikvincent 0:05ccbd4f84f1 149 /* lwIP replacement for your libc malloc() */
hendrikvincent 0:05ccbd4f84f1 150
hendrikvincent 0:05ccbd4f84f1 151 /**
hendrikvincent 0:05ccbd4f84f1 152 * The heap is made up as a list of structs of this type.
hendrikvincent 0:05ccbd4f84f1 153 * This does not have to be aligned since for getting its size,
hendrikvincent 0:05ccbd4f84f1 154 * we only use the macro SIZEOF_STRUCT_MEM, which automatically alignes.
hendrikvincent 0:05ccbd4f84f1 155 */
hendrikvincent 0:05ccbd4f84f1 156 struct mem {
hendrikvincent 0:05ccbd4f84f1 157 /** index (-> ram[next]) of the next struct */
hendrikvincent 0:05ccbd4f84f1 158 mem_size_t next;
hendrikvincent 0:05ccbd4f84f1 159 /** index (-> ram[prev]) of the previous struct */
hendrikvincent 0:05ccbd4f84f1 160 mem_size_t prev;
hendrikvincent 0:05ccbd4f84f1 161 /** 1: this area is used; 0: this area is unused */
hendrikvincent 0:05ccbd4f84f1 162 u8_t used;
hendrikvincent 0:05ccbd4f84f1 163 };
hendrikvincent 0:05ccbd4f84f1 164
hendrikvincent 0:05ccbd4f84f1 165 /** All allocated blocks will be MIN_SIZE bytes big, at least!
hendrikvincent 0:05ccbd4f84f1 166 * MIN_SIZE can be overridden to suit your needs. Smaller values save space,
hendrikvincent 0:05ccbd4f84f1 167 * larger values could prevent too small blocks to fragment the RAM too much. */
hendrikvincent 0:05ccbd4f84f1 168 #ifndef MIN_SIZE
hendrikvincent 0:05ccbd4f84f1 169 #define MIN_SIZE 12
hendrikvincent 0:05ccbd4f84f1 170 #endif /* MIN_SIZE */
hendrikvincent 0:05ccbd4f84f1 171 /* some alignment macros: we define them here for better source code layout */
hendrikvincent 0:05ccbd4f84f1 172 #define MIN_SIZE_ALIGNED LWIP_MEM_ALIGN_SIZE(MIN_SIZE)
hendrikvincent 0:05ccbd4f84f1 173 #define SIZEOF_STRUCT_MEM LWIP_MEM_ALIGN_SIZE(sizeof(struct mem))
hendrikvincent 0:05ccbd4f84f1 174 #define MEM_SIZE_ALIGNED LWIP_MEM_ALIGN_SIZE(MEM_SIZE)
hendrikvincent 0:05ccbd4f84f1 175
hendrikvincent 0:05ccbd4f84f1 176 /** If you want to relocate the heap to external memory, simply define
hendrikvincent 0:05ccbd4f84f1 177 * LWIP_RAM_HEAP_POINTER as a void-pointer to that location.
hendrikvincent 0:05ccbd4f84f1 178 * If so, make sure the memory at that location is big enough (see below on
hendrikvincent 0:05ccbd4f84f1 179 * how that space is calculated). */
hendrikvincent 0:05ccbd4f84f1 180 #ifndef LWIP_RAM_HEAP_POINTER
hendrikvincent 0:05ccbd4f84f1 181 /** the heap. we need one struct mem at the end and some room for alignment */
hendrikvincent 0:05ccbd4f84f1 182 u8_t ram_heap[MEM_SIZE_ALIGNED + (2*SIZEOF_STRUCT_MEM) + MEM_ALIGNMENT] MEM_POSITION;
hendrikvincent 0:05ccbd4f84f1 183 #define LWIP_RAM_HEAP_POINTER ram_heap
hendrikvincent 0:05ccbd4f84f1 184 #endif /* LWIP_RAM_HEAP_POINTER */
hendrikvincent 0:05ccbd4f84f1 185
hendrikvincent 0:05ccbd4f84f1 186 /** pointer to the heap (ram_heap): for alignment, ram is now a pointer instead of an array */
hendrikvincent 0:05ccbd4f84f1 187 static u8_t *ram;
hendrikvincent 0:05ccbd4f84f1 188 /** the last entry, always unused! */
hendrikvincent 0:05ccbd4f84f1 189 static struct mem *ram_end;
hendrikvincent 0:05ccbd4f84f1 190 /** pointer to the lowest free block, this is used for faster search */
hendrikvincent 0:05ccbd4f84f1 191 static struct mem *lfree;
hendrikvincent 0:05ccbd4f84f1 192
hendrikvincent 0:05ccbd4f84f1 193 /** concurrent access protection */
hendrikvincent 0:05ccbd4f84f1 194 static sys_mutex_t mem_mutex;
hendrikvincent 0:05ccbd4f84f1 195
hendrikvincent 0:05ccbd4f84f1 196 #if LWIP_ALLOW_MEM_FREE_FROM_OTHER_CONTEXT
hendrikvincent 0:05ccbd4f84f1 197
hendrikvincent 0:05ccbd4f84f1 198 static volatile u8_t mem_free_count;
hendrikvincent 0:05ccbd4f84f1 199
hendrikvincent 0:05ccbd4f84f1 200 /* Allow mem_free from other (e.g. interrupt) context */
hendrikvincent 0:05ccbd4f84f1 201 #define LWIP_MEM_FREE_DECL_PROTECT() SYS_ARCH_DECL_PROTECT(lev_free)
hendrikvincent 0:05ccbd4f84f1 202 #define LWIP_MEM_FREE_PROTECT() SYS_ARCH_PROTECT(lev_free)
hendrikvincent 0:05ccbd4f84f1 203 #define LWIP_MEM_FREE_UNPROTECT() SYS_ARCH_UNPROTECT(lev_free)
hendrikvincent 0:05ccbd4f84f1 204 #define LWIP_MEM_ALLOC_DECL_PROTECT() SYS_ARCH_DECL_PROTECT(lev_alloc)
hendrikvincent 0:05ccbd4f84f1 205 #define LWIP_MEM_ALLOC_PROTECT() SYS_ARCH_PROTECT(lev_alloc)
hendrikvincent 0:05ccbd4f84f1 206 #define LWIP_MEM_ALLOC_UNPROTECT() SYS_ARCH_UNPROTECT(lev_alloc)
hendrikvincent 0:05ccbd4f84f1 207
hendrikvincent 0:05ccbd4f84f1 208 #else /* LWIP_ALLOW_MEM_FREE_FROM_OTHER_CONTEXT */
hendrikvincent 0:05ccbd4f84f1 209
hendrikvincent 0:05ccbd4f84f1 210 /* Protect the heap only by using a semaphore */
hendrikvincent 0:05ccbd4f84f1 211 #define LWIP_MEM_FREE_DECL_PROTECT()
hendrikvincent 0:05ccbd4f84f1 212 #define LWIP_MEM_FREE_PROTECT() sys_mutex_lock(&mem_mutex)
hendrikvincent 0:05ccbd4f84f1 213 #define LWIP_MEM_FREE_UNPROTECT() sys_mutex_unlock(&mem_mutex)
hendrikvincent 0:05ccbd4f84f1 214 /* mem_malloc is protected using semaphore AND LWIP_MEM_ALLOC_PROTECT */
hendrikvincent 0:05ccbd4f84f1 215 #define LWIP_MEM_ALLOC_DECL_PROTECT()
hendrikvincent 0:05ccbd4f84f1 216 #define LWIP_MEM_ALLOC_PROTECT()
hendrikvincent 0:05ccbd4f84f1 217 #define LWIP_MEM_ALLOC_UNPROTECT()
hendrikvincent 0:05ccbd4f84f1 218
hendrikvincent 0:05ccbd4f84f1 219 #endif /* LWIP_ALLOW_MEM_FREE_FROM_OTHER_CONTEXT */
hendrikvincent 0:05ccbd4f84f1 220
hendrikvincent 0:05ccbd4f84f1 221
hendrikvincent 0:05ccbd4f84f1 222 /**
hendrikvincent 0:05ccbd4f84f1 223 * "Plug holes" by combining adjacent empty struct mems.
hendrikvincent 0:05ccbd4f84f1 224 * After this function is through, there should not exist
hendrikvincent 0:05ccbd4f84f1 225 * one empty struct mem pointing to another empty struct mem.
hendrikvincent 0:05ccbd4f84f1 226 *
hendrikvincent 0:05ccbd4f84f1 227 * @param mem this points to a struct mem which just has been freed
hendrikvincent 0:05ccbd4f84f1 228 * @internal this function is only called by mem_free() and mem_trim()
hendrikvincent 0:05ccbd4f84f1 229 *
hendrikvincent 0:05ccbd4f84f1 230 * This assumes access to the heap is protected by the calling function
hendrikvincent 0:05ccbd4f84f1 231 * already.
hendrikvincent 0:05ccbd4f84f1 232 */
hendrikvincent 0:05ccbd4f84f1 233 static void
hendrikvincent 0:05ccbd4f84f1 234 plug_holes(struct mem *mem)
hendrikvincent 0:05ccbd4f84f1 235 {
hendrikvincent 0:05ccbd4f84f1 236 struct mem *nmem;
hendrikvincent 0:05ccbd4f84f1 237 struct mem *pmem;
hendrikvincent 0:05ccbd4f84f1 238
hendrikvincent 0:05ccbd4f84f1 239 LWIP_ASSERT("plug_holes: mem >= ram", (u8_t *)mem >= ram);
hendrikvincent 0:05ccbd4f84f1 240 LWIP_ASSERT("plug_holes: mem < ram_end", (u8_t *)mem < (u8_t *)ram_end);
hendrikvincent 0:05ccbd4f84f1 241 LWIP_ASSERT("plug_holes: mem->used == 0", mem->used == 0);
hendrikvincent 0:05ccbd4f84f1 242
hendrikvincent 0:05ccbd4f84f1 243 /* plug hole forward */
hendrikvincent 0:05ccbd4f84f1 244 LWIP_ASSERT("plug_holes: mem->next <= MEM_SIZE_ALIGNED", mem->next <= MEM_SIZE_ALIGNED);
hendrikvincent 0:05ccbd4f84f1 245
hendrikvincent 0:05ccbd4f84f1 246 nmem = (struct mem *)(void *)&ram[mem->next];
hendrikvincent 0:05ccbd4f84f1 247 if (mem != nmem && nmem->used == 0 && (u8_t *)nmem != (u8_t *)ram_end) {
hendrikvincent 0:05ccbd4f84f1 248 /* if mem->next is unused and not end of ram, combine mem and mem->next */
hendrikvincent 0:05ccbd4f84f1 249 if (lfree == nmem) {
hendrikvincent 0:05ccbd4f84f1 250 lfree = mem;
hendrikvincent 0:05ccbd4f84f1 251 }
hendrikvincent 0:05ccbd4f84f1 252 mem->next = nmem->next;
hendrikvincent 0:05ccbd4f84f1 253 ((struct mem *)(void *)&ram[nmem->next])->prev = (mem_size_t)((u8_t *)mem - ram);
hendrikvincent 0:05ccbd4f84f1 254 }
hendrikvincent 0:05ccbd4f84f1 255
hendrikvincent 0:05ccbd4f84f1 256 /* plug hole backward */
hendrikvincent 0:05ccbd4f84f1 257 pmem = (struct mem *)(void *)&ram[mem->prev];
hendrikvincent 0:05ccbd4f84f1 258 if (pmem != mem && pmem->used == 0) {
hendrikvincent 0:05ccbd4f84f1 259 /* if mem->prev is unused, combine mem and mem->prev */
hendrikvincent 0:05ccbd4f84f1 260 if (lfree == mem) {
hendrikvincent 0:05ccbd4f84f1 261 lfree = pmem;
hendrikvincent 0:05ccbd4f84f1 262 }
hendrikvincent 0:05ccbd4f84f1 263 pmem->next = mem->next;
hendrikvincent 0:05ccbd4f84f1 264 ((struct mem *)(void *)&ram[mem->next])->prev = (mem_size_t)((u8_t *)pmem - ram);
hendrikvincent 0:05ccbd4f84f1 265 }
hendrikvincent 0:05ccbd4f84f1 266 }
hendrikvincent 0:05ccbd4f84f1 267
hendrikvincent 0:05ccbd4f84f1 268 /**
hendrikvincent 0:05ccbd4f84f1 269 * Zero the heap and initialize start, end and lowest-free
hendrikvincent 0:05ccbd4f84f1 270 */
hendrikvincent 0:05ccbd4f84f1 271 void
hendrikvincent 0:05ccbd4f84f1 272 mem_init(void)
hendrikvincent 0:05ccbd4f84f1 273 {
hendrikvincent 0:05ccbd4f84f1 274 struct mem *mem;
hendrikvincent 0:05ccbd4f84f1 275
hendrikvincent 0:05ccbd4f84f1 276 LWIP_ASSERT("Sanity check alignment",
hendrikvincent 0:05ccbd4f84f1 277 (SIZEOF_STRUCT_MEM & (MEM_ALIGNMENT-1)) == 0);
hendrikvincent 0:05ccbd4f84f1 278
hendrikvincent 0:05ccbd4f84f1 279 /* align the heap */
hendrikvincent 0:05ccbd4f84f1 280 ram = (u8_t *)LWIP_MEM_ALIGN(LWIP_RAM_HEAP_POINTER);
hendrikvincent 0:05ccbd4f84f1 281 /* initialize the start of the heap */
hendrikvincent 0:05ccbd4f84f1 282 mem = (struct mem *)(void *)ram;
hendrikvincent 0:05ccbd4f84f1 283 mem->next = MEM_SIZE_ALIGNED;
hendrikvincent 0:05ccbd4f84f1 284 mem->prev = 0;
hendrikvincent 0:05ccbd4f84f1 285 mem->used = 0;
hendrikvincent 0:05ccbd4f84f1 286 /* initialize the end of the heap */
hendrikvincent 0:05ccbd4f84f1 287 ram_end = (struct mem *)(void *)&ram[MEM_SIZE_ALIGNED];
hendrikvincent 0:05ccbd4f84f1 288 ram_end->used = 1;
hendrikvincent 0:05ccbd4f84f1 289 ram_end->next = MEM_SIZE_ALIGNED;
hendrikvincent 0:05ccbd4f84f1 290 ram_end->prev = MEM_SIZE_ALIGNED;
hendrikvincent 0:05ccbd4f84f1 291
hendrikvincent 0:05ccbd4f84f1 292 /* initialize the lowest-free pointer to the start of the heap */
hendrikvincent 0:05ccbd4f84f1 293 lfree = (struct mem *)(void *)ram;
hendrikvincent 0:05ccbd4f84f1 294
hendrikvincent 0:05ccbd4f84f1 295 MEM_STATS_AVAIL(avail, MEM_SIZE_ALIGNED);
hendrikvincent 0:05ccbd4f84f1 296
hendrikvincent 0:05ccbd4f84f1 297 if(sys_mutex_new(&mem_mutex) != ERR_OK) {
hendrikvincent 0:05ccbd4f84f1 298 LWIP_ASSERT("failed to create mem_mutex", 0);
hendrikvincent 0:05ccbd4f84f1 299 }
hendrikvincent 0:05ccbd4f84f1 300 }
hendrikvincent 0:05ccbd4f84f1 301
hendrikvincent 0:05ccbd4f84f1 302 /**
hendrikvincent 0:05ccbd4f84f1 303 * Put a struct mem back on the heap
hendrikvincent 0:05ccbd4f84f1 304 *
hendrikvincent 0:05ccbd4f84f1 305 * @param rmem is the data portion of a struct mem as returned by a previous
hendrikvincent 0:05ccbd4f84f1 306 * call to mem_malloc()
hendrikvincent 0:05ccbd4f84f1 307 */
hendrikvincent 0:05ccbd4f84f1 308 void
hendrikvincent 0:05ccbd4f84f1 309 mem_free(void *rmem)
hendrikvincent 0:05ccbd4f84f1 310 {
hendrikvincent 0:05ccbd4f84f1 311 struct mem *mem;
hendrikvincent 0:05ccbd4f84f1 312 LWIP_MEM_FREE_DECL_PROTECT();
hendrikvincent 0:05ccbd4f84f1 313
hendrikvincent 0:05ccbd4f84f1 314 if (rmem == NULL) {
hendrikvincent 0:05ccbd4f84f1 315 LWIP_DEBUGF(MEM_DEBUG | LWIP_DBG_TRACE | LWIP_DBG_LEVEL_SERIOUS, ("mem_free(p == NULL) was called.\n"));
hendrikvincent 0:05ccbd4f84f1 316 return;
hendrikvincent 0:05ccbd4f84f1 317 }
hendrikvincent 0:05ccbd4f84f1 318 LWIP_ASSERT("mem_free: sanity check alignment", (((mem_ptr_t)rmem) & (MEM_ALIGNMENT-1)) == 0);
hendrikvincent 0:05ccbd4f84f1 319
hendrikvincent 0:05ccbd4f84f1 320 LWIP_ASSERT("mem_free: legal memory", (u8_t *)rmem >= (u8_t *)ram &&
hendrikvincent 0:05ccbd4f84f1 321 (u8_t *)rmem < (u8_t *)ram_end);
hendrikvincent 0:05ccbd4f84f1 322
hendrikvincent 0:05ccbd4f84f1 323 if ((u8_t *)rmem < (u8_t *)ram || (u8_t *)rmem >= (u8_t *)ram_end) {
hendrikvincent 0:05ccbd4f84f1 324 SYS_ARCH_DECL_PROTECT(lev);
hendrikvincent 0:05ccbd4f84f1 325 LWIP_DEBUGF(MEM_DEBUG | LWIP_DBG_LEVEL_SEVERE, ("mem_free: illegal memory\n"));
hendrikvincent 0:05ccbd4f84f1 326 /* protect mem stats from concurrent access */
hendrikvincent 0:05ccbd4f84f1 327 SYS_ARCH_PROTECT(lev);
hendrikvincent 0:05ccbd4f84f1 328 MEM_STATS_INC(illegal);
hendrikvincent 0:05ccbd4f84f1 329 SYS_ARCH_UNPROTECT(lev);
hendrikvincent 0:05ccbd4f84f1 330 return;
hendrikvincent 0:05ccbd4f84f1 331 }
hendrikvincent 0:05ccbd4f84f1 332 /* protect the heap from concurrent access */
hendrikvincent 0:05ccbd4f84f1 333 LWIP_MEM_FREE_PROTECT();
hendrikvincent 0:05ccbd4f84f1 334 /* Get the corresponding struct mem ... */
hendrikvincent 0:05ccbd4f84f1 335 mem = (struct mem *)(void *)((u8_t *)rmem - SIZEOF_STRUCT_MEM);
hendrikvincent 0:05ccbd4f84f1 336 /* ... which has to be in a used state ... */
hendrikvincent 0:05ccbd4f84f1 337 LWIP_ASSERT("mem_free: mem->used", mem->used);
hendrikvincent 0:05ccbd4f84f1 338 /* ... and is now unused. */
hendrikvincent 0:05ccbd4f84f1 339 mem->used = 0;
hendrikvincent 0:05ccbd4f84f1 340
hendrikvincent 0:05ccbd4f84f1 341 if (mem < lfree) {
hendrikvincent 0:05ccbd4f84f1 342 /* the newly freed struct is now the lowest */
hendrikvincent 0:05ccbd4f84f1 343 lfree = mem;
hendrikvincent 0:05ccbd4f84f1 344 }
hendrikvincent 0:05ccbd4f84f1 345
hendrikvincent 0:05ccbd4f84f1 346 MEM_STATS_DEC_USED(used, mem->next - (mem_size_t)(((u8_t *)mem - ram)));
hendrikvincent 0:05ccbd4f84f1 347
hendrikvincent 0:05ccbd4f84f1 348 /* finally, see if prev or next are free also */
hendrikvincent 0:05ccbd4f84f1 349 plug_holes(mem);
hendrikvincent 0:05ccbd4f84f1 350 #if LWIP_ALLOW_MEM_FREE_FROM_OTHER_CONTEXT
hendrikvincent 0:05ccbd4f84f1 351 mem_free_count = 1;
hendrikvincent 0:05ccbd4f84f1 352 #endif /* LWIP_ALLOW_MEM_FREE_FROM_OTHER_CONTEXT */
hendrikvincent 0:05ccbd4f84f1 353 LWIP_MEM_FREE_UNPROTECT();
hendrikvincent 0:05ccbd4f84f1 354 }
hendrikvincent 0:05ccbd4f84f1 355
hendrikvincent 0:05ccbd4f84f1 356 /**
hendrikvincent 0:05ccbd4f84f1 357 * Shrink memory returned by mem_malloc().
hendrikvincent 0:05ccbd4f84f1 358 *
hendrikvincent 0:05ccbd4f84f1 359 * @param rmem pointer to memory allocated by mem_malloc the is to be shrinked
hendrikvincent 0:05ccbd4f84f1 360 * @param newsize required size after shrinking (needs to be smaller than or
hendrikvincent 0:05ccbd4f84f1 361 * equal to the previous size)
hendrikvincent 0:05ccbd4f84f1 362 * @return for compatibility reasons: is always == rmem, at the moment
hendrikvincent 0:05ccbd4f84f1 363 * or NULL if newsize is > old size, in which case rmem is NOT touched
hendrikvincent 0:05ccbd4f84f1 364 * or freed!
hendrikvincent 0:05ccbd4f84f1 365 */
hendrikvincent 0:05ccbd4f84f1 366 void *
hendrikvincent 0:05ccbd4f84f1 367 mem_trim(void *rmem, mem_size_t newsize)
hendrikvincent 0:05ccbd4f84f1 368 {
hendrikvincent 0:05ccbd4f84f1 369 mem_size_t size;
hendrikvincent 0:05ccbd4f84f1 370 mem_size_t ptr, ptr2;
hendrikvincent 0:05ccbd4f84f1 371 struct mem *mem, *mem2;
hendrikvincent 0:05ccbd4f84f1 372 /* use the FREE_PROTECT here: it protects with sem OR SYS_ARCH_PROTECT */
hendrikvincent 0:05ccbd4f84f1 373 LWIP_MEM_FREE_DECL_PROTECT();
hendrikvincent 0:05ccbd4f84f1 374
hendrikvincent 0:05ccbd4f84f1 375 /* Expand the size of the allocated memory region so that we can
hendrikvincent 0:05ccbd4f84f1 376 adjust for alignment. */
hendrikvincent 0:05ccbd4f84f1 377 newsize = LWIP_MEM_ALIGN_SIZE(newsize);
hendrikvincent 0:05ccbd4f84f1 378
hendrikvincent 0:05ccbd4f84f1 379 if(newsize < MIN_SIZE_ALIGNED) {
hendrikvincent 0:05ccbd4f84f1 380 /* every data block must be at least MIN_SIZE_ALIGNED long */
hendrikvincent 0:05ccbd4f84f1 381 newsize = MIN_SIZE_ALIGNED;
hendrikvincent 0:05ccbd4f84f1 382 }
hendrikvincent 0:05ccbd4f84f1 383
hendrikvincent 0:05ccbd4f84f1 384 if (newsize > MEM_SIZE_ALIGNED) {
hendrikvincent 0:05ccbd4f84f1 385 return NULL;
hendrikvincent 0:05ccbd4f84f1 386 }
hendrikvincent 0:05ccbd4f84f1 387
hendrikvincent 0:05ccbd4f84f1 388 LWIP_ASSERT("mem_trim: legal memory", (u8_t *)rmem >= (u8_t *)ram &&
hendrikvincent 0:05ccbd4f84f1 389 (u8_t *)rmem < (u8_t *)ram_end);
hendrikvincent 0:05ccbd4f84f1 390
hendrikvincent 0:05ccbd4f84f1 391 if ((u8_t *)rmem < (u8_t *)ram || (u8_t *)rmem >= (u8_t *)ram_end) {
hendrikvincent 0:05ccbd4f84f1 392 SYS_ARCH_DECL_PROTECT(lev);
hendrikvincent 0:05ccbd4f84f1 393 LWIP_DEBUGF(MEM_DEBUG | LWIP_DBG_LEVEL_SEVERE, ("mem_trim: illegal memory\n"));
hendrikvincent 0:05ccbd4f84f1 394 /* protect mem stats from concurrent access */
hendrikvincent 0:05ccbd4f84f1 395 SYS_ARCH_PROTECT(lev);
hendrikvincent 0:05ccbd4f84f1 396 MEM_STATS_INC(illegal);
hendrikvincent 0:05ccbd4f84f1 397 SYS_ARCH_UNPROTECT(lev);
hendrikvincent 0:05ccbd4f84f1 398 return rmem;
hendrikvincent 0:05ccbd4f84f1 399 }
hendrikvincent 0:05ccbd4f84f1 400 /* Get the corresponding struct mem ... */
hendrikvincent 0:05ccbd4f84f1 401 mem = (struct mem *)(void *)((u8_t *)rmem - SIZEOF_STRUCT_MEM);
hendrikvincent 0:05ccbd4f84f1 402 /* ... and its offset pointer */
hendrikvincent 0:05ccbd4f84f1 403 ptr = (mem_size_t)((u8_t *)mem - ram);
hendrikvincent 0:05ccbd4f84f1 404
hendrikvincent 0:05ccbd4f84f1 405 size = mem->next - ptr - SIZEOF_STRUCT_MEM;
hendrikvincent 0:05ccbd4f84f1 406 LWIP_ASSERT("mem_trim can only shrink memory", newsize <= size);
hendrikvincent 0:05ccbd4f84f1 407 if (newsize > size) {
hendrikvincent 0:05ccbd4f84f1 408 /* not supported */
hendrikvincent 0:05ccbd4f84f1 409 return NULL;
hendrikvincent 0:05ccbd4f84f1 410 }
hendrikvincent 0:05ccbd4f84f1 411 if (newsize == size) {
hendrikvincent 0:05ccbd4f84f1 412 /* No change in size, simply return */
hendrikvincent 0:05ccbd4f84f1 413 return rmem;
hendrikvincent 0:05ccbd4f84f1 414 }
hendrikvincent 0:05ccbd4f84f1 415
hendrikvincent 0:05ccbd4f84f1 416 /* protect the heap from concurrent access */
hendrikvincent 0:05ccbd4f84f1 417 LWIP_MEM_FREE_PROTECT();
hendrikvincent 0:05ccbd4f84f1 418
hendrikvincent 0:05ccbd4f84f1 419 mem2 = (struct mem *)(void *)&ram[mem->next];
hendrikvincent 0:05ccbd4f84f1 420 if(mem2->used == 0) {
hendrikvincent 0:05ccbd4f84f1 421 /* The next struct is unused, we can simply move it at little */
hendrikvincent 0:05ccbd4f84f1 422 mem_size_t next;
hendrikvincent 0:05ccbd4f84f1 423 /* remember the old next pointer */
hendrikvincent 0:05ccbd4f84f1 424 next = mem2->next;
hendrikvincent 0:05ccbd4f84f1 425 /* create new struct mem which is moved directly after the shrinked mem */
hendrikvincent 0:05ccbd4f84f1 426 ptr2 = ptr + SIZEOF_STRUCT_MEM + newsize;
hendrikvincent 0:05ccbd4f84f1 427 if (lfree == mem2) {
hendrikvincent 0:05ccbd4f84f1 428 lfree = (struct mem *)(void *)&ram[ptr2];
hendrikvincent 0:05ccbd4f84f1 429 }
hendrikvincent 0:05ccbd4f84f1 430 mem2 = (struct mem *)(void *)&ram[ptr2];
hendrikvincent 0:05ccbd4f84f1 431 mem2->used = 0;
hendrikvincent 0:05ccbd4f84f1 432 /* restore the next pointer */
hendrikvincent 0:05ccbd4f84f1 433 mem2->next = next;
hendrikvincent 0:05ccbd4f84f1 434 /* link it back to mem */
hendrikvincent 0:05ccbd4f84f1 435 mem2->prev = ptr;
hendrikvincent 0:05ccbd4f84f1 436 /* link mem to it */
hendrikvincent 0:05ccbd4f84f1 437 mem->next = ptr2;
hendrikvincent 0:05ccbd4f84f1 438 /* last thing to restore linked list: as we have moved mem2,
hendrikvincent 0:05ccbd4f84f1 439 * let 'mem2->next->prev' point to mem2 again. but only if mem2->next is not
hendrikvincent 0:05ccbd4f84f1 440 * the end of the heap */
hendrikvincent 0:05ccbd4f84f1 441 if (mem2->next != MEM_SIZE_ALIGNED) {
hendrikvincent 0:05ccbd4f84f1 442 ((struct mem *)(void *)&ram[mem2->next])->prev = ptr2;
hendrikvincent 0:05ccbd4f84f1 443 }
hendrikvincent 0:05ccbd4f84f1 444 MEM_STATS_DEC_USED(used, (size - newsize));
hendrikvincent 0:05ccbd4f84f1 445 /* no need to plug holes, we've already done that */
hendrikvincent 0:05ccbd4f84f1 446 } else if (newsize + SIZEOF_STRUCT_MEM + MIN_SIZE_ALIGNED <= size) {
hendrikvincent 0:05ccbd4f84f1 447 /* Next struct is used but there's room for another struct mem with
hendrikvincent 0:05ccbd4f84f1 448 * at least MIN_SIZE_ALIGNED of data.
hendrikvincent 0:05ccbd4f84f1 449 * Old size ('size') must be big enough to contain at least 'newsize' plus a struct mem
hendrikvincent 0:05ccbd4f84f1 450 * ('SIZEOF_STRUCT_MEM') with some data ('MIN_SIZE_ALIGNED').
hendrikvincent 0:05ccbd4f84f1 451 * @todo we could leave out MIN_SIZE_ALIGNED. We would create an empty
hendrikvincent 0:05ccbd4f84f1 452 * region that couldn't hold data, but when mem->next gets freed,
hendrikvincent 0:05ccbd4f84f1 453 * the 2 regions would be combined, resulting in more free memory */
hendrikvincent 0:05ccbd4f84f1 454 ptr2 = ptr + SIZEOF_STRUCT_MEM + newsize;
hendrikvincent 0:05ccbd4f84f1 455 mem2 = (struct mem *)(void *)&ram[ptr2];
hendrikvincent 0:05ccbd4f84f1 456 if (mem2 < lfree) {
hendrikvincent 0:05ccbd4f84f1 457 lfree = mem2;
hendrikvincent 0:05ccbd4f84f1 458 }
hendrikvincent 0:05ccbd4f84f1 459 mem2->used = 0;
hendrikvincent 0:05ccbd4f84f1 460 mem2->next = mem->next;
hendrikvincent 0:05ccbd4f84f1 461 mem2->prev = ptr;
hendrikvincent 0:05ccbd4f84f1 462 mem->next = ptr2;
hendrikvincent 0:05ccbd4f84f1 463 if (mem2->next != MEM_SIZE_ALIGNED) {
hendrikvincent 0:05ccbd4f84f1 464 ((struct mem *)(void *)&ram[mem2->next])->prev = ptr2;
hendrikvincent 0:05ccbd4f84f1 465 }
hendrikvincent 0:05ccbd4f84f1 466 MEM_STATS_DEC_USED(used, (size - newsize));
hendrikvincent 0:05ccbd4f84f1 467 /* the original mem->next is used, so no need to plug holes! */
hendrikvincent 0:05ccbd4f84f1 468 }
hendrikvincent 0:05ccbd4f84f1 469 /* else {
hendrikvincent 0:05ccbd4f84f1 470 next struct mem is used but size between mem and mem2 is not big enough
hendrikvincent 0:05ccbd4f84f1 471 to create another struct mem
hendrikvincent 0:05ccbd4f84f1 472 -> don't do anyhting.
hendrikvincent 0:05ccbd4f84f1 473 -> the remaining space stays unused since it is too small
hendrikvincent 0:05ccbd4f84f1 474 } */
hendrikvincent 0:05ccbd4f84f1 475 #if LWIP_ALLOW_MEM_FREE_FROM_OTHER_CONTEXT
hendrikvincent 0:05ccbd4f84f1 476 mem_free_count = 1;
hendrikvincent 0:05ccbd4f84f1 477 #endif /* LWIP_ALLOW_MEM_FREE_FROM_OTHER_CONTEXT */
hendrikvincent 0:05ccbd4f84f1 478 LWIP_MEM_FREE_UNPROTECT();
hendrikvincent 0:05ccbd4f84f1 479 return rmem;
hendrikvincent 0:05ccbd4f84f1 480 }
hendrikvincent 0:05ccbd4f84f1 481
hendrikvincent 0:05ccbd4f84f1 482 /**
hendrikvincent 0:05ccbd4f84f1 483 * Adam's mem_malloc() plus solution for bug #17922
hendrikvincent 0:05ccbd4f84f1 484 * Allocate a block of memory with a minimum of 'size' bytes.
hendrikvincent 0:05ccbd4f84f1 485 *
hendrikvincent 0:05ccbd4f84f1 486 * @param size is the minimum size of the requested block in bytes.
hendrikvincent 0:05ccbd4f84f1 487 * @return pointer to allocated memory or NULL if no free memory was found.
hendrikvincent 0:05ccbd4f84f1 488 *
hendrikvincent 0:05ccbd4f84f1 489 * Note that the returned value will always be aligned (as defined by MEM_ALIGNMENT).
hendrikvincent 0:05ccbd4f84f1 490 */
hendrikvincent 0:05ccbd4f84f1 491 void *
hendrikvincent 0:05ccbd4f84f1 492 mem_malloc(mem_size_t size)
hendrikvincent 0:05ccbd4f84f1 493 {
hendrikvincent 0:05ccbd4f84f1 494 mem_size_t ptr, ptr2;
hendrikvincent 0:05ccbd4f84f1 495 struct mem *mem, *mem2;
hendrikvincent 0:05ccbd4f84f1 496 #if LWIP_ALLOW_MEM_FREE_FROM_OTHER_CONTEXT
hendrikvincent 0:05ccbd4f84f1 497 u8_t local_mem_free_count = 0;
hendrikvincent 0:05ccbd4f84f1 498 #endif /* LWIP_ALLOW_MEM_FREE_FROM_OTHER_CONTEXT */
hendrikvincent 0:05ccbd4f84f1 499 LWIP_MEM_ALLOC_DECL_PROTECT();
hendrikvincent 0:05ccbd4f84f1 500
hendrikvincent 0:05ccbd4f84f1 501 if (size == 0) {
hendrikvincent 0:05ccbd4f84f1 502 return NULL;
hendrikvincent 0:05ccbd4f84f1 503 }
hendrikvincent 0:05ccbd4f84f1 504
hendrikvincent 0:05ccbd4f84f1 505 /* Expand the size of the allocated memory region so that we can
hendrikvincent 0:05ccbd4f84f1 506 adjust for alignment. */
hendrikvincent 0:05ccbd4f84f1 507 size = LWIP_MEM_ALIGN_SIZE(size);
hendrikvincent 0:05ccbd4f84f1 508
hendrikvincent 0:05ccbd4f84f1 509 if(size < MIN_SIZE_ALIGNED) {
hendrikvincent 0:05ccbd4f84f1 510 /* every data block must be at least MIN_SIZE_ALIGNED long */
hendrikvincent 0:05ccbd4f84f1 511 size = MIN_SIZE_ALIGNED;
hendrikvincent 0:05ccbd4f84f1 512 }
hendrikvincent 0:05ccbd4f84f1 513
hendrikvincent 0:05ccbd4f84f1 514 if (size > MEM_SIZE_ALIGNED) {
hendrikvincent 0:05ccbd4f84f1 515 return NULL;
hendrikvincent 0:05ccbd4f84f1 516 }
hendrikvincent 0:05ccbd4f84f1 517
hendrikvincent 0:05ccbd4f84f1 518 /* protect the heap from concurrent access */
hendrikvincent 0:05ccbd4f84f1 519 sys_mutex_lock(&mem_mutex);
hendrikvincent 0:05ccbd4f84f1 520 LWIP_MEM_ALLOC_PROTECT();
hendrikvincent 0:05ccbd4f84f1 521 #if LWIP_ALLOW_MEM_FREE_FROM_OTHER_CONTEXT
hendrikvincent 0:05ccbd4f84f1 522 /* run as long as a mem_free disturbed mem_malloc */
hendrikvincent 0:05ccbd4f84f1 523 do {
hendrikvincent 0:05ccbd4f84f1 524 local_mem_free_count = 0;
hendrikvincent 0:05ccbd4f84f1 525 #endif /* LWIP_ALLOW_MEM_FREE_FROM_OTHER_CONTEXT */
hendrikvincent 0:05ccbd4f84f1 526
hendrikvincent 0:05ccbd4f84f1 527 /* Scan through the heap searching for a free block that is big enough,
hendrikvincent 0:05ccbd4f84f1 528 * beginning with the lowest free block.
hendrikvincent 0:05ccbd4f84f1 529 */
hendrikvincent 0:05ccbd4f84f1 530 for (ptr = (mem_size_t)((u8_t *)lfree - ram); ptr < MEM_SIZE_ALIGNED - size;
hendrikvincent 0:05ccbd4f84f1 531 ptr = ((struct mem *)(void *)&ram[ptr])->next) {
hendrikvincent 0:05ccbd4f84f1 532 mem = (struct mem *)(void *)&ram[ptr];
hendrikvincent 0:05ccbd4f84f1 533 #if LWIP_ALLOW_MEM_FREE_FROM_OTHER_CONTEXT
hendrikvincent 0:05ccbd4f84f1 534 mem_free_count = 0;
hendrikvincent 0:05ccbd4f84f1 535 LWIP_MEM_ALLOC_UNPROTECT();
hendrikvincent 0:05ccbd4f84f1 536 /* allow mem_free to run */
hendrikvincent 0:05ccbd4f84f1 537 LWIP_MEM_ALLOC_PROTECT();
hendrikvincent 0:05ccbd4f84f1 538 if (mem_free_count != 0) {
hendrikvincent 0:05ccbd4f84f1 539 local_mem_free_count = mem_free_count;
hendrikvincent 0:05ccbd4f84f1 540 }
hendrikvincent 0:05ccbd4f84f1 541 mem_free_count = 0;
hendrikvincent 0:05ccbd4f84f1 542 #endif /* LWIP_ALLOW_MEM_FREE_FROM_OTHER_CONTEXT */
hendrikvincent 0:05ccbd4f84f1 543
hendrikvincent 0:05ccbd4f84f1 544 if ((!mem->used) &&
hendrikvincent 0:05ccbd4f84f1 545 (mem->next - (ptr + SIZEOF_STRUCT_MEM)) >= size) {
hendrikvincent 0:05ccbd4f84f1 546 /* mem is not used and at least perfect fit is possible:
hendrikvincent 0:05ccbd4f84f1 547 * mem->next - (ptr + SIZEOF_STRUCT_MEM) gives us the 'user data size' of mem */
hendrikvincent 0:05ccbd4f84f1 548
hendrikvincent 0:05ccbd4f84f1 549 if (mem->next - (ptr + SIZEOF_STRUCT_MEM) >= (size + SIZEOF_STRUCT_MEM + MIN_SIZE_ALIGNED)) {
hendrikvincent 0:05ccbd4f84f1 550 /* (in addition to the above, we test if another struct mem (SIZEOF_STRUCT_MEM) containing
hendrikvincent 0:05ccbd4f84f1 551 * at least MIN_SIZE_ALIGNED of data also fits in the 'user data space' of 'mem')
hendrikvincent 0:05ccbd4f84f1 552 * -> split large block, create empty remainder,
hendrikvincent 0:05ccbd4f84f1 553 * remainder must be large enough to contain MIN_SIZE_ALIGNED data: if
hendrikvincent 0:05ccbd4f84f1 554 * mem->next - (ptr + (2*SIZEOF_STRUCT_MEM)) == size,
hendrikvincent 0:05ccbd4f84f1 555 * struct mem would fit in but no data between mem2 and mem2->next
hendrikvincent 0:05ccbd4f84f1 556 * @todo we could leave out MIN_SIZE_ALIGNED. We would create an empty
hendrikvincent 0:05ccbd4f84f1 557 * region that couldn't hold data, but when mem->next gets freed,
hendrikvincent 0:05ccbd4f84f1 558 * the 2 regions would be combined, resulting in more free memory
hendrikvincent 0:05ccbd4f84f1 559 */
hendrikvincent 0:05ccbd4f84f1 560 ptr2 = ptr + SIZEOF_STRUCT_MEM + size;
hendrikvincent 0:05ccbd4f84f1 561 /* create mem2 struct */
hendrikvincent 0:05ccbd4f84f1 562 mem2 = (struct mem *)(void *)&ram[ptr2];
hendrikvincent 0:05ccbd4f84f1 563 mem2->used = 0;
hendrikvincent 0:05ccbd4f84f1 564 mem2->next = mem->next;
hendrikvincent 0:05ccbd4f84f1 565 mem2->prev = ptr;
hendrikvincent 0:05ccbd4f84f1 566 /* and insert it between mem and mem->next */
hendrikvincent 0:05ccbd4f84f1 567 mem->next = ptr2;
hendrikvincent 0:05ccbd4f84f1 568 mem->used = 1;
hendrikvincent 0:05ccbd4f84f1 569
hendrikvincent 0:05ccbd4f84f1 570 if (mem2->next != MEM_SIZE_ALIGNED) {
hendrikvincent 0:05ccbd4f84f1 571 ((struct mem *)(void *)&ram[mem2->next])->prev = ptr2;
hendrikvincent 0:05ccbd4f84f1 572 }
hendrikvincent 0:05ccbd4f84f1 573 MEM_STATS_INC_USED(used, (size + SIZEOF_STRUCT_MEM));
hendrikvincent 0:05ccbd4f84f1 574 } else {
hendrikvincent 0:05ccbd4f84f1 575 /* (a mem2 struct does no fit into the user data space of mem and mem->next will always
hendrikvincent 0:05ccbd4f84f1 576 * be used at this point: if not we have 2 unused structs in a row, plug_holes should have
hendrikvincent 0:05ccbd4f84f1 577 * take care of this).
hendrikvincent 0:05ccbd4f84f1 578 * -> near fit or excact fit: do not split, no mem2 creation
hendrikvincent 0:05ccbd4f84f1 579 * also can't move mem->next directly behind mem, since mem->next
hendrikvincent 0:05ccbd4f84f1 580 * will always be used at this point!
hendrikvincent 0:05ccbd4f84f1 581 */
hendrikvincent 0:05ccbd4f84f1 582 mem->used = 1;
hendrikvincent 0:05ccbd4f84f1 583 MEM_STATS_INC_USED(used, mem->next - (mem_size_t)((u8_t *)mem - ram));
hendrikvincent 0:05ccbd4f84f1 584 }
hendrikvincent 0:05ccbd4f84f1 585
hendrikvincent 0:05ccbd4f84f1 586 if (mem == lfree) {
hendrikvincent 0:05ccbd4f84f1 587 /* Find next free block after mem and update lowest free pointer */
hendrikvincent 0:05ccbd4f84f1 588 while (lfree->used && lfree != ram_end) {
hendrikvincent 0:05ccbd4f84f1 589 LWIP_MEM_ALLOC_UNPROTECT();
hendrikvincent 0:05ccbd4f84f1 590 /* prevent high interrupt latency... */
hendrikvincent 0:05ccbd4f84f1 591 LWIP_MEM_ALLOC_PROTECT();
hendrikvincent 0:05ccbd4f84f1 592 lfree = (struct mem *)(void *)&ram[lfree->next];
hendrikvincent 0:05ccbd4f84f1 593 }
hendrikvincent 0:05ccbd4f84f1 594 LWIP_ASSERT("mem_malloc: !lfree->used", ((lfree == ram_end) || (!lfree->used)));
hendrikvincent 0:05ccbd4f84f1 595 }
hendrikvincent 0:05ccbd4f84f1 596 LWIP_MEM_ALLOC_UNPROTECT();
hendrikvincent 0:05ccbd4f84f1 597 sys_mutex_unlock(&mem_mutex);
hendrikvincent 0:05ccbd4f84f1 598 LWIP_ASSERT("mem_malloc: allocated memory not above ram_end.",
hendrikvincent 0:05ccbd4f84f1 599 (mem_ptr_t)mem + SIZEOF_STRUCT_MEM + size <= (mem_ptr_t)ram_end);
hendrikvincent 0:05ccbd4f84f1 600 LWIP_ASSERT("mem_malloc: allocated memory properly aligned.",
hendrikvincent 0:05ccbd4f84f1 601 ((mem_ptr_t)mem + SIZEOF_STRUCT_MEM) % MEM_ALIGNMENT == 0);
hendrikvincent 0:05ccbd4f84f1 602 LWIP_ASSERT("mem_malloc: sanity check alignment",
hendrikvincent 0:05ccbd4f84f1 603 (((mem_ptr_t)mem) & (MEM_ALIGNMENT-1)) == 0);
hendrikvincent 0:05ccbd4f84f1 604
hendrikvincent 0:05ccbd4f84f1 605 return (u8_t *)mem + SIZEOF_STRUCT_MEM;
hendrikvincent 0:05ccbd4f84f1 606 }
hendrikvincent 0:05ccbd4f84f1 607 }
hendrikvincent 0:05ccbd4f84f1 608 #if LWIP_ALLOW_MEM_FREE_FROM_OTHER_CONTEXT
hendrikvincent 0:05ccbd4f84f1 609 /* if we got interrupted by a mem_free, try again */
hendrikvincent 0:05ccbd4f84f1 610 } while(local_mem_free_count != 0);
hendrikvincent 0:05ccbd4f84f1 611 #endif /* LWIP_ALLOW_MEM_FREE_FROM_OTHER_CONTEXT */
hendrikvincent 0:05ccbd4f84f1 612 LWIP_DEBUGF(MEM_DEBUG | LWIP_DBG_LEVEL_SERIOUS, ("mem_malloc: could not allocate %"S16_F" bytes\n", (s16_t)size));
hendrikvincent 0:05ccbd4f84f1 613 MEM_STATS_INC(err);
hendrikvincent 0:05ccbd4f84f1 614 LWIP_MEM_ALLOC_UNPROTECT();
hendrikvincent 0:05ccbd4f84f1 615 sys_mutex_unlock(&mem_mutex);
hendrikvincent 0:05ccbd4f84f1 616 return NULL;
hendrikvincent 0:05ccbd4f84f1 617 }
hendrikvincent 0:05ccbd4f84f1 618
hendrikvincent 0:05ccbd4f84f1 619 #endif /* MEM_USE_POOLS */
hendrikvincent 0:05ccbd4f84f1 620 /**
hendrikvincent 0:05ccbd4f84f1 621 * Contiguously allocates enough space for count objects that are size bytes
hendrikvincent 0:05ccbd4f84f1 622 * of memory each and returns a pointer to the allocated memory.
hendrikvincent 0:05ccbd4f84f1 623 *
hendrikvincent 0:05ccbd4f84f1 624 * The allocated memory is filled with bytes of value zero.
hendrikvincent 0:05ccbd4f84f1 625 *
hendrikvincent 0:05ccbd4f84f1 626 * @param count number of objects to allocate
hendrikvincent 0:05ccbd4f84f1 627 * @param size size of the objects to allocate
hendrikvincent 0:05ccbd4f84f1 628 * @return pointer to allocated memory / NULL pointer if there is an error
hendrikvincent 0:05ccbd4f84f1 629 */
hendrikvincent 0:05ccbd4f84f1 630 void *mem_calloc(mem_size_t count, mem_size_t size)
hendrikvincent 0:05ccbd4f84f1 631 {
hendrikvincent 0:05ccbd4f84f1 632 void *p;
hendrikvincent 0:05ccbd4f84f1 633
hendrikvincent 0:05ccbd4f84f1 634 /* allocate 'count' objects of size 'size' */
hendrikvincent 0:05ccbd4f84f1 635 p = mem_malloc(count * size);
hendrikvincent 0:05ccbd4f84f1 636 if (p) {
hendrikvincent 0:05ccbd4f84f1 637 /* zero the memory */
hendrikvincent 0:05ccbd4f84f1 638 memset(p, 0, count * size);
hendrikvincent 0:05ccbd4f84f1 639 }
hendrikvincent 0:05ccbd4f84f1 640 return p;
hendrikvincent 0:05ccbd4f84f1 641 }
hendrikvincent 0:05ccbd4f84f1 642
hendrikvincent 0:05ccbd4f84f1 643 #endif /* !MEM_LIBC_MALLOC */