[457] | 1 | /**
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| 2 | * @file
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| 3 | * Dynamic memory manager
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| 4 | *
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| 5 | * This is a lightweight replacement for the standard C library malloc().
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| 6 | *
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| 7 | * If you want to use the standard C library malloc() instead, define
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| 8 | * MEM_LIBC_MALLOC to 1 in your lwipopts.h
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| 9 | *
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| 10 | * To let mem_malloc() use pools (prevents fragmentation and is much faster than
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| 11 | * a heap but might waste some memory), define MEM_USE_POOLS to 1, define
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| 12 | * MEMP_USE_CUSTOM_POOLS to 1 and create a file "lwippools.h" that includes a list
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| 13 | * of pools like this (more pools can be added between _START and _END):
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| 14 | *
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| 15 | * Define three pools with sizes 256, 512, and 1512 bytes
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| 16 | * LWIP_MALLOC_MEMPOOL_START
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| 17 | * LWIP_MALLOC_MEMPOOL(20, 256)
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| 18 | * LWIP_MALLOC_MEMPOOL(10, 512)
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| 19 | * LWIP_MALLOC_MEMPOOL(5, 1512)
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| 20 | * LWIP_MALLOC_MEMPOOL_END
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| 21 | */
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| 22 |
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| 23 | /*
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| 24 | * Copyright (c) 2001-2004 Swedish Institute of Computer Science.
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| 25 | * All rights reserved.
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| 26 | *
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| 27 | * Redistribution and use in source and binary forms, with or without modification,
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| 28 | * are permitted provided that the following conditions are met:
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| 29 | *
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| 30 | * 1. Redistributions of source code must retain the above copyright notice,
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| 31 | * this list of conditions and the following disclaimer.
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| 32 | * 2. Redistributions in binary form must reproduce the above copyright notice,
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| 33 | * this list of conditions and the following disclaimer in the documentation
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| 34 | * and/or other materials provided with the distribution.
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| 35 | * 3. The name of the author may not be used to endorse or promote products
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| 36 | * derived from this software without specific prior written permission.
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| 37 | *
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| 38 | * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR IMPLIED
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| 39 | * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
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| 40 | * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT
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| 41 | * SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
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| 42 | * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT
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| 43 | * OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
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| 44 | * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
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| 45 | * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
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| 46 | * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY
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| 47 | * OF SUCH DAMAGE.
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| 48 | *
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| 49 | * This file is part of the lwIP TCP/IP stack.
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| 50 | *
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| 51 | * Author: Adam Dunkels <adam@sics.se>
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| 52 | * Simon Goldschmidt
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| 53 | *
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| 54 | */
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| 55 |
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| 56 | #include "lwip/opt.h"
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| 57 | #include "lwip/mem.h"
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| 58 | #include "lwip/def.h"
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| 59 | #include "lwip/sys.h"
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| 60 | #include "lwip/stats.h"
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| 61 | #include "lwip/err.h"
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| 62 |
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| 63 | #include <string.h>
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| 64 |
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| 65 | #if MEM_LIBC_MALLOC
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| 66 | #include <stdlib.h> /* for malloc()/free() */
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| 67 | #endif
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| 68 |
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| 69 | /* This is overridable for tests only... */
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| 70 | #ifndef LWIP_MEM_ILLEGAL_FREE
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| 71 | #define LWIP_MEM_ILLEGAL_FREE(msg) LWIP_ASSERT(msg, 0)
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| 72 | #endif
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| 73 |
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| 74 | #define MEM_STATS_INC_LOCKED(x) SYS_ARCH_LOCKED(MEM_STATS_INC(x))
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| 75 | #define MEM_STATS_INC_USED_LOCKED(x, y) SYS_ARCH_LOCKED(MEM_STATS_INC_USED(x, y))
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| 76 | #define MEM_STATS_DEC_USED_LOCKED(x, y) SYS_ARCH_LOCKED(MEM_STATS_DEC_USED(x, y))
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| 77 |
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| 78 | #if MEM_OVERFLOW_CHECK
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| 79 | #define MEM_SANITY_OFFSET MEM_SANITY_REGION_BEFORE_ALIGNED
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| 80 | #define MEM_SANITY_OVERHEAD (MEM_SANITY_REGION_BEFORE_ALIGNED + MEM_SANITY_REGION_AFTER_ALIGNED)
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| 81 | #else
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| 82 | #define MEM_SANITY_OFFSET 0
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| 83 | #define MEM_SANITY_OVERHEAD 0
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| 84 | #endif
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| 85 |
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| 86 | #if MEM_OVERFLOW_CHECK || MEMP_OVERFLOW_CHECK
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| 87 | /**
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| 88 | * Check if a mep element was victim of an overflow or underflow
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| 89 | * (e.g. the restricted area after/before it has been altered)
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| 90 | *
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| 91 | * @param p the mem element to check
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| 92 | * @param size allocated size of the element
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| 93 | * @param descr1 description of the element source shown on error
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| 94 | * @param descr2 description of the element source shown on error
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| 95 | */
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| 96 | void
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| 97 | mem_overflow_check_raw(void *p, size_t size, const char *descr1, const char *descr2)
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| 98 | {
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| 99 | #if MEM_SANITY_REGION_AFTER_ALIGNED || MEM_SANITY_REGION_BEFORE_ALIGNED
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| 100 | u16_t k;
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| 101 | u8_t *m;
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| 102 |
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| 103 | #if MEM_SANITY_REGION_AFTER_ALIGNED > 0
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| 104 | m = (u8_t *)p + size;
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| 105 | for (k = 0; k < MEM_SANITY_REGION_AFTER_ALIGNED; k++) {
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| 106 | if (m[k] != 0xcd) {
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| 107 | char errstr[128];
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| 108 | snprintf(errstr, sizeof(errstr), "detected mem overflow in %s%s", descr1, descr2);
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| 109 | LWIP_ASSERT(errstr, 0);
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| 110 | }
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| 111 | }
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| 112 | #endif /* MEM_SANITY_REGION_AFTER_ALIGNED > 0 */
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| 113 |
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| 114 | #if MEM_SANITY_REGION_BEFORE_ALIGNED > 0
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| 115 | m = (u8_t *)p - MEM_SANITY_REGION_BEFORE_ALIGNED;
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| 116 | for (k = 0; k < MEM_SANITY_REGION_BEFORE_ALIGNED; k++) {
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| 117 | if (m[k] != 0xcd) {
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| 118 | char errstr[128];
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| 119 | snprintf(errstr, sizeof(errstr), "detected mem underflow in %s%s", descr1, descr2);
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| 120 | LWIP_ASSERT(errstr, 0);
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| 121 | }
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| 122 | }
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| 123 | #endif /* MEM_SANITY_REGION_BEFORE_ALIGNED > 0 */
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| 124 | #else
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| 125 | LWIP_UNUSED_ARG(p);
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| 126 | LWIP_UNUSED_ARG(desc);
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| 127 | LWIP_UNUSED_ARG(descr);
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| 128 | #endif
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| 129 | }
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| 130 |
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| 131 | /**
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| 132 | * Initialize the restricted area of a mem element.
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| 133 | */
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| 134 | void
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| 135 | mem_overflow_init_raw(void *p, size_t size)
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| 136 | {
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| 137 | #if MEM_SANITY_REGION_BEFORE_ALIGNED > 0 || MEM_SANITY_REGION_AFTER_ALIGNED > 0
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| 138 | u8_t *m;
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| 139 | #if MEM_SANITY_REGION_BEFORE_ALIGNED > 0
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| 140 | m = (u8_t *)p - MEM_SANITY_REGION_BEFORE_ALIGNED;
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| 141 | memset(m, 0xcd, MEM_SANITY_REGION_BEFORE_ALIGNED);
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| 142 | #endif
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| 143 | #if MEM_SANITY_REGION_AFTER_ALIGNED > 0
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| 144 | m = (u8_t *)p + size;
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| 145 | memset(m, 0xcd, MEM_SANITY_REGION_AFTER_ALIGNED);
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| 146 | #endif
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| 147 | #else /* MEM_SANITY_REGION_BEFORE_ALIGNED > 0 || MEM_SANITY_REGION_AFTER_ALIGNED > 0 */
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| 148 | LWIP_UNUSED_ARG(p);
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| 149 | LWIP_UNUSED_ARG(desc);
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| 150 | #endif /* MEM_SANITY_REGION_BEFORE_ALIGNED > 0 || MEM_SANITY_REGION_AFTER_ALIGNED > 0 */
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| 151 | }
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| 152 | #endif /* MEM_OVERFLOW_CHECK || MEMP_OVERFLOW_CHECK */
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| 153 |
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| 154 | #if MEM_LIBC_MALLOC || MEM_USE_POOLS
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| 155 |
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| 156 | /** mem_init is not used when using pools instead of a heap or using
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| 157 | * C library malloc().
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| 158 | */
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| 159 | void
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| 160 | mem_init(void)
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| 161 | {
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| 162 | }
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| 163 |
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| 164 | /** mem_trim is not used when using pools instead of a heap or using
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| 165 | * C library malloc(): we can't free part of a pool element and the stack
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| 166 | * support mem_trim() to return a different pointer
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| 167 | */
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| 168 | void *
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| 169 | mem_trim(void *mem, mem_size_t size)
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| 170 | {
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| 171 | LWIP_UNUSED_ARG(size);
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| 172 | return mem;
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| 173 | }
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| 174 | #endif /* MEM_LIBC_MALLOC || MEM_USE_POOLS */
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| 175 |
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| 176 | #if MEM_LIBC_MALLOC
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| 177 | /* lwIP heap implemented using C library malloc() */
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| 178 |
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| 179 | /* in case C library malloc() needs extra protection,
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| 180 | * allow these defines to be overridden.
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| 181 | */
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| 182 | #ifndef mem_clib_free
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| 183 | #define mem_clib_free free
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| 184 | #endif
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| 185 | #ifndef mem_clib_malloc
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| 186 | #define mem_clib_malloc malloc
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| 187 | #endif
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| 188 | #ifndef mem_clib_calloc
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| 189 | #define mem_clib_calloc calloc
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| 190 | #endif
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| 191 |
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| 192 | #if LWIP_STATS && MEM_STATS
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| 193 | #define MEM_LIBC_STATSHELPER_SIZE LWIP_MEM_ALIGN_SIZE(sizeof(mem_size_t))
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| 194 | #else
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| 195 | #define MEM_LIBC_STATSHELPER_SIZE 0
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| 196 | #endif
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| 197 |
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| 198 | /**
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| 199 | * Allocate a block of memory with a minimum of 'size' bytes.
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| 200 | *
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| 201 | * @param size is the minimum size of the requested block in bytes.
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| 202 | * @return pointer to allocated memory or NULL if no free memory was found.
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| 203 | *
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| 204 | * Note that the returned value must always be aligned (as defined by MEM_ALIGNMENT).
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| 205 | */
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| 206 | void *
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| 207 | mem_malloc(mem_size_t size)
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| 208 | {
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| 209 | void *ret = mem_clib_malloc(size + MEM_LIBC_STATSHELPER_SIZE);
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| 210 | if (ret == NULL) {
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| 211 | MEM_STATS_INC_LOCKED(err);
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| 212 | } else {
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| 213 | LWIP_ASSERT("malloc() must return aligned memory", LWIP_MEM_ALIGN(ret) == ret);
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| 214 | #if LWIP_STATS && MEM_STATS
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| 215 | *(mem_size_t *)ret = size;
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| 216 | ret = (u8_t *)ret + MEM_LIBC_STATSHELPER_SIZE;
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| 217 | MEM_STATS_INC_USED_LOCKED(used, size);
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| 218 | #endif
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| 219 | }
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| 220 | return ret;
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| 221 | }
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| 222 |
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| 223 | /** Put memory back on the heap
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| 224 | *
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| 225 | * @param rmem is the pointer as returned by a previous call to mem_malloc()
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| 226 | */
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| 227 | void
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| 228 | mem_free(void *rmem)
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| 229 | {
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| 230 | LWIP_ASSERT("rmem != NULL", (rmem != NULL));
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| 231 | LWIP_ASSERT("rmem == MEM_ALIGN(rmem)", (rmem == LWIP_MEM_ALIGN(rmem)));
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| 232 | #if LWIP_STATS && MEM_STATS
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| 233 | rmem = (u8_t *)rmem - MEM_LIBC_STATSHELPER_SIZE;
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| 234 | MEM_STATS_DEC_USED_LOCKED(used, *(mem_size_t *)rmem);
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| 235 | #endif
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| 236 | mem_clib_free(rmem);
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| 237 | }
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| 238 |
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| 239 | #elif MEM_USE_POOLS
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| 240 |
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| 241 | /* lwIP heap implemented with different sized pools */
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| 242 |
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| 243 | /**
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| 244 | * Allocate memory: determine the smallest pool that is big enough
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| 245 | * to contain an element of 'size' and get an element from that pool.
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| 246 | *
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| 247 | * @param size the size in bytes of the memory needed
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| 248 | * @return a pointer to the allocated memory or NULL if the pool is empty
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| 249 | */
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| 250 | void *
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| 251 | mem_malloc(mem_size_t size)
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| 252 | {
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| 253 | void *ret;
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| 254 | struct memp_malloc_helper *element = NULL;
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| 255 | memp_t poolnr;
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| 256 | mem_size_t required_size = size + LWIP_MEM_ALIGN_SIZE(sizeof(struct memp_malloc_helper));
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| 257 |
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| 258 | for (poolnr = MEMP_POOL_FIRST; poolnr <= MEMP_POOL_LAST; poolnr = (memp_t)(poolnr + 1)) {
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| 259 | /* is this pool big enough to hold an element of the required size
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| 260 | plus a struct memp_malloc_helper that saves the pool this element came from? */
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| 261 | if (required_size <= memp_pools[poolnr]->size) {
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| 262 | element = (struct memp_malloc_helper *)memp_malloc(poolnr);
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| 263 | if (element == NULL) {
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| 264 | /* No need to DEBUGF or ASSERT: This error is already taken care of in memp.c */
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| 265 | #if MEM_USE_POOLS_TRY_BIGGER_POOL
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| 266 | /** Try a bigger pool if this one is empty! */
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| 267 | if (poolnr < MEMP_POOL_LAST) {
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| 268 | continue;
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| 269 | }
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| 270 | #endif /* MEM_USE_POOLS_TRY_BIGGER_POOL */
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| 271 | MEM_STATS_INC_LOCKED(err);
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| 272 | return NULL;
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| 273 | }
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| 274 | break;
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| 275 | }
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| 276 | }
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| 277 | if (poolnr > MEMP_POOL_LAST) {
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| 278 | LWIP_ASSERT("mem_malloc(): no pool is that big!", 0);
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| 279 | MEM_STATS_INC_LOCKED(err);
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| 280 | return NULL;
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| 281 | }
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| 282 |
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| 283 | /* save the pool number this element came from */
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| 284 | element->poolnr = poolnr;
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| 285 | /* and return a pointer to the memory directly after the struct memp_malloc_helper */
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| 286 | ret = (u8_t *)element + LWIP_MEM_ALIGN_SIZE(sizeof(struct memp_malloc_helper));
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| 287 |
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| 288 | #if MEMP_OVERFLOW_CHECK || (LWIP_STATS && MEM_STATS)
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| 289 | /* truncating to u16_t is safe because struct memp_desc::size is u16_t */
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| 290 | element->size = (u16_t)size;
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| 291 | MEM_STATS_INC_USED_LOCKED(used, element->size);
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| 292 | #endif /* MEMP_OVERFLOW_CHECK || (LWIP_STATS && MEM_STATS) */
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| 293 | #if MEMP_OVERFLOW_CHECK
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| 294 | /* initialize unused memory (diff between requested size and selected pool's size) */
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| 295 | memset((u8_t *)ret + size, 0xcd, memp_pools[poolnr]->size - size);
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| 296 | #endif /* MEMP_OVERFLOW_CHECK */
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| 297 | return ret;
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| 298 | }
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| 299 |
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| 300 | /**
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| 301 | * Free memory previously allocated by mem_malloc. Loads the pool number
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| 302 | * and calls memp_free with that pool number to put the element back into
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| 303 | * its pool
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| 304 | *
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| 305 | * @param rmem the memory element to free
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| 306 | */
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| 307 | void
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| 308 | mem_free(void *rmem)
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| 309 | {
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| 310 | struct memp_malloc_helper *hmem;
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| 311 |
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| 312 | LWIP_ASSERT("rmem != NULL", (rmem != NULL));
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| 313 | LWIP_ASSERT("rmem == MEM_ALIGN(rmem)", (rmem == LWIP_MEM_ALIGN(rmem)));
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| 314 |
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| 315 | /* get the original struct memp_malloc_helper */
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| 316 | /* cast through void* to get rid of alignment warnings */
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| 317 | hmem = (struct memp_malloc_helper *)(void *)((u8_t *)rmem - LWIP_MEM_ALIGN_SIZE(sizeof(struct memp_malloc_helper)));
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| 318 |
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| 319 | LWIP_ASSERT("hmem != NULL", (hmem != NULL));
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| 320 | LWIP_ASSERT("hmem == MEM_ALIGN(hmem)", (hmem == LWIP_MEM_ALIGN(hmem)));
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| 321 | LWIP_ASSERT("hmem->poolnr < MEMP_MAX", (hmem->poolnr < MEMP_MAX));
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| 322 |
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| 323 | MEM_STATS_DEC_USED_LOCKED(used, hmem->size);
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| 324 | #if MEMP_OVERFLOW_CHECK
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| 325 | {
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| 326 | u16_t i;
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| 327 | LWIP_ASSERT("MEM_USE_POOLS: invalid chunk size",
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| 328 | hmem->size <= memp_pools[hmem->poolnr]->size);
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| 329 | /* check that unused memory remained untouched (diff between requested size and selected pool's size) */
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| 330 | for (i = hmem->size; i < memp_pools[hmem->poolnr]->size; i++) {
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| 331 | u8_t data = *((u8_t *)rmem + i);
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| 332 | LWIP_ASSERT("MEM_USE_POOLS: mem overflow detected", data == 0xcd);
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| 333 | }
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| 334 | }
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| 335 | #endif /* MEMP_OVERFLOW_CHECK */
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| 336 |
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| 337 | /* and put it in the pool we saved earlier */
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| 338 | memp_free(hmem->poolnr, hmem);
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| 339 | }
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| 340 |
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| 341 | #else /* MEM_USE_POOLS */
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| 342 | /* lwIP replacement for your libc malloc() */
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| 343 |
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| 344 | /**
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| 345 | * The heap is made up as a list of structs of this type.
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| 346 | * This does not have to be aligned since for getting its size,
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| 347 | * we only use the macro SIZEOF_STRUCT_MEM, which automatically aligns.
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| 348 | */
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| 349 | struct mem {
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| 350 | /** index (-> ram[next]) of the next struct */
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| 351 | mem_size_t next;
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| 352 | /** index (-> ram[prev]) of the previous struct */
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| 353 | mem_size_t prev;
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| 354 | /** 1: this area is used; 0: this area is unused */
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| 355 | u8_t used;
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| 356 | #if MEM_OVERFLOW_CHECK
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| 357 | /** this keeps track of the user allocation size for guard checks */
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| 358 | mem_size_t user_size;
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| 359 | #endif
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| 360 | };
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| 361 |
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| 362 | /** All allocated blocks will be MIN_SIZE bytes big, at least!
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| 363 | * MIN_SIZE can be overridden to suit your needs. Smaller values save space,
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| 364 | * larger values could prevent too small blocks to fragment the RAM too much. */
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| 365 | #ifndef MIN_SIZE
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| 366 | #define MIN_SIZE 12
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| 367 | #endif /* MIN_SIZE */
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| 368 | /* some alignment macros: we define them here for better source code layout */
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| 369 | #define MIN_SIZE_ALIGNED LWIP_MEM_ALIGN_SIZE(MIN_SIZE)
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| 370 | #define SIZEOF_STRUCT_MEM LWIP_MEM_ALIGN_SIZE(sizeof(struct mem))
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| 371 | #define MEM_SIZE_ALIGNED LWIP_MEM_ALIGN_SIZE(MEM_SIZE)
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| 372 |
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| 373 | /** If you want to relocate the heap to external memory, simply define
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| 374 | * LWIP_RAM_HEAP_POINTER as a void-pointer to that location.
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| 375 | * If so, make sure the memory at that location is big enough (see below on
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| 376 | * how that space is calculated). */
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| 377 | #ifndef LWIP_RAM_HEAP_POINTER
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| 378 | /** the heap. we need one struct mem at the end and some room for alignment */
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| 379 | LWIP_DECLARE_MEMORY_ALIGNED(ram_heap, MEM_SIZE_ALIGNED + (2U * SIZEOF_STRUCT_MEM));
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| 380 | #define LWIP_RAM_HEAP_POINTER ram_heap
|
---|
| 381 | #endif /* LWIP_RAM_HEAP_POINTER */
|
---|
| 382 |
|
---|
| 383 | /** pointer to the heap (ram_heap): for alignment, ram is now a pointer instead of an array */
|
---|
| 384 | static u8_t *ram;
|
---|
| 385 | /** the last entry, always unused! */
|
---|
| 386 | static struct mem *ram_end;
|
---|
| 387 |
|
---|
| 388 | /** concurrent access protection */
|
---|
| 389 | #if !NO_SYS
|
---|
| 390 | static sys_mutex_t mem_mutex;
|
---|
| 391 | #endif
|
---|
| 392 |
|
---|
| 393 | #if LWIP_ALLOW_MEM_FREE_FROM_OTHER_CONTEXT
|
---|
| 394 |
|
---|
| 395 | static volatile u8_t mem_free_count;
|
---|
| 396 |
|
---|
| 397 | /* Allow mem_free from other (e.g. interrupt) context */
|
---|
| 398 | #define LWIP_MEM_FREE_DECL_PROTECT() SYS_ARCH_DECL_PROTECT(lev_free)
|
---|
| 399 | #define LWIP_MEM_FREE_PROTECT() SYS_ARCH_PROTECT(lev_free)
|
---|
| 400 | #define LWIP_MEM_FREE_UNPROTECT() SYS_ARCH_UNPROTECT(lev_free)
|
---|
| 401 | #define LWIP_MEM_ALLOC_DECL_PROTECT() SYS_ARCH_DECL_PROTECT(lev_alloc)
|
---|
| 402 | #define LWIP_MEM_ALLOC_PROTECT() SYS_ARCH_PROTECT(lev_alloc)
|
---|
| 403 | #define LWIP_MEM_ALLOC_UNPROTECT() SYS_ARCH_UNPROTECT(lev_alloc)
|
---|
| 404 | #define LWIP_MEM_LFREE_VOLATILE volatile
|
---|
| 405 |
|
---|
| 406 | #else /* LWIP_ALLOW_MEM_FREE_FROM_OTHER_CONTEXT */
|
---|
| 407 |
|
---|
| 408 | /* Protect the heap only by using a mutex */
|
---|
| 409 | #define LWIP_MEM_FREE_DECL_PROTECT()
|
---|
| 410 | #define LWIP_MEM_FREE_PROTECT() sys_mutex_lock(&mem_mutex)
|
---|
| 411 | #define LWIP_MEM_FREE_UNPROTECT() sys_mutex_unlock(&mem_mutex)
|
---|
| 412 | /* mem_malloc is protected using mutex AND LWIP_MEM_ALLOC_PROTECT */
|
---|
| 413 | #define LWIP_MEM_ALLOC_DECL_PROTECT()
|
---|
| 414 | #define LWIP_MEM_ALLOC_PROTECT()
|
---|
| 415 | #define LWIP_MEM_ALLOC_UNPROTECT()
|
---|
| 416 | #define LWIP_MEM_LFREE_VOLATILE
|
---|
| 417 |
|
---|
| 418 | #endif /* LWIP_ALLOW_MEM_FREE_FROM_OTHER_CONTEXT */
|
---|
| 419 |
|
---|
| 420 | /** pointer to the lowest free block, this is used for faster search */
|
---|
| 421 | static struct mem * LWIP_MEM_LFREE_VOLATILE lfree;
|
---|
| 422 |
|
---|
| 423 | #if MEM_SANITY_CHECK
|
---|
| 424 | static void mem_sanity(void);
|
---|
| 425 | #define MEM_SANITY() mem_sanity()
|
---|
| 426 | #else
|
---|
| 427 | #define MEM_SANITY()
|
---|
| 428 | #endif
|
---|
| 429 |
|
---|
| 430 | #if MEM_OVERFLOW_CHECK
|
---|
| 431 | static void
|
---|
| 432 | mem_overflow_init_element(struct mem *mem, mem_size_t user_size)
|
---|
| 433 | {
|
---|
| 434 | void *p = (u8_t *)mem + SIZEOF_STRUCT_MEM + MEM_SANITY_OFFSET;
|
---|
| 435 | mem->user_size = user_size;
|
---|
| 436 | mem_overflow_init_raw(p, user_size);
|
---|
| 437 | }
|
---|
| 438 |
|
---|
| 439 | static void
|
---|
| 440 | mem_overflow_check_element(struct mem *mem)
|
---|
| 441 | {
|
---|
| 442 | void *p = (u8_t *)mem + SIZEOF_STRUCT_MEM + MEM_SANITY_OFFSET;
|
---|
| 443 | mem_overflow_check_raw(p, mem->user_size, "heap", "");
|
---|
| 444 | }
|
---|
| 445 | #else /* MEM_OVERFLOW_CHECK */
|
---|
| 446 | #define mem_overflow_init_element(mem, size)
|
---|
| 447 | #define mem_overflow_check_element(mem)
|
---|
| 448 | #endif /* MEM_OVERFLOW_CHECK */
|
---|
| 449 |
|
---|
| 450 | static struct mem *
|
---|
| 451 | ptr_to_mem(mem_size_t ptr)
|
---|
| 452 | {
|
---|
| 453 | return (struct mem *)(void *)&ram[ptr];
|
---|
| 454 | }
|
---|
| 455 |
|
---|
| 456 | static mem_size_t
|
---|
| 457 | mem_to_ptr(void *mem)
|
---|
| 458 | {
|
---|
| 459 | return (mem_size_t)((u8_t *)mem - ram);
|
---|
| 460 | }
|
---|
| 461 |
|
---|
| 462 | /**
|
---|
| 463 | * "Plug holes" by combining adjacent empty struct mems.
|
---|
| 464 | * After this function is through, there should not exist
|
---|
| 465 | * one empty struct mem pointing to another empty struct mem.
|
---|
| 466 | *
|
---|
| 467 | * @param mem this points to a struct mem which just has been freed
|
---|
| 468 | * @internal this function is only called by mem_free() and mem_trim()
|
---|
| 469 | *
|
---|
| 470 | * This assumes access to the heap is protected by the calling function
|
---|
| 471 | * already.
|
---|
| 472 | */
|
---|
| 473 | static void
|
---|
| 474 | plug_holes(struct mem *mem)
|
---|
| 475 | {
|
---|
| 476 | struct mem *nmem;
|
---|
| 477 | struct mem *pmem;
|
---|
| 478 |
|
---|
| 479 | LWIP_ASSERT("plug_holes: mem >= ram", (u8_t *)mem >= ram);
|
---|
| 480 | LWIP_ASSERT("plug_holes: mem < ram_end", (u8_t *)mem < (u8_t *)ram_end);
|
---|
| 481 | LWIP_ASSERT("plug_holes: mem->used == 0", mem->used == 0);
|
---|
| 482 |
|
---|
| 483 | /* plug hole forward */
|
---|
| 484 | LWIP_ASSERT("plug_holes: mem->next <= MEM_SIZE_ALIGNED", mem->next <= MEM_SIZE_ALIGNED);
|
---|
| 485 |
|
---|
| 486 | nmem = ptr_to_mem(mem->next);
|
---|
| 487 | if (mem != nmem && nmem->used == 0 && (u8_t *)nmem != (u8_t *)ram_end) {
|
---|
| 488 | /* if mem->next is unused and not end of ram, combine mem and mem->next */
|
---|
| 489 | if (lfree == nmem) {
|
---|
| 490 | lfree = mem;
|
---|
| 491 | }
|
---|
| 492 | mem->next = nmem->next;
|
---|
| 493 | if (nmem->next != MEM_SIZE_ALIGNED) {
|
---|
| 494 | ptr_to_mem(nmem->next)->prev = mem_to_ptr(mem);
|
---|
| 495 | }
|
---|
| 496 | }
|
---|
| 497 |
|
---|
| 498 | /* plug hole backward */
|
---|
| 499 | pmem = ptr_to_mem(mem->prev);
|
---|
| 500 | if (pmem != mem && pmem->used == 0) {
|
---|
| 501 | /* if mem->prev is unused, combine mem and mem->prev */
|
---|
| 502 | if (lfree == mem) {
|
---|
| 503 | lfree = pmem;
|
---|
| 504 | }
|
---|
| 505 | pmem->next = mem->next;
|
---|
| 506 | if (mem->next != MEM_SIZE_ALIGNED) {
|
---|
| 507 | ptr_to_mem(mem->next)->prev = mem_to_ptr(pmem);
|
---|
| 508 | }
|
---|
| 509 | }
|
---|
| 510 | }
|
---|
| 511 |
|
---|
| 512 | /**
|
---|
| 513 | * Zero the heap and initialize start, end and lowest-free
|
---|
| 514 | */
|
---|
| 515 | void
|
---|
| 516 | mem_init(void)
|
---|
| 517 | {
|
---|
| 518 | struct mem *mem;
|
---|
| 519 |
|
---|
| 520 | LWIP_ASSERT("Sanity check alignment",
|
---|
| 521 | (SIZEOF_STRUCT_MEM & (MEM_ALIGNMENT - 1)) == 0);
|
---|
| 522 |
|
---|
| 523 | /* align the heap */
|
---|
| 524 | ram = (u8_t *)LWIP_MEM_ALIGN(LWIP_RAM_HEAP_POINTER);
|
---|
| 525 | /* initialize the start of the heap */
|
---|
| 526 | mem = (struct mem *)(void *)ram;
|
---|
| 527 | mem->next = MEM_SIZE_ALIGNED;
|
---|
| 528 | mem->prev = 0;
|
---|
| 529 | mem->used = 0;
|
---|
| 530 | /* initialize the end of the heap */
|
---|
| 531 | ram_end = ptr_to_mem(MEM_SIZE_ALIGNED);
|
---|
| 532 | ram_end->used = 1;
|
---|
| 533 | ram_end->next = MEM_SIZE_ALIGNED;
|
---|
| 534 | ram_end->prev = MEM_SIZE_ALIGNED;
|
---|
| 535 | MEM_SANITY();
|
---|
| 536 |
|
---|
| 537 | /* initialize the lowest-free pointer to the start of the heap */
|
---|
| 538 | lfree = (struct mem *)(void *)ram;
|
---|
| 539 |
|
---|
| 540 | MEM_STATS_AVAIL(avail, MEM_SIZE_ALIGNED);
|
---|
| 541 |
|
---|
| 542 | if (sys_mutex_new(&mem_mutex) != ERR_OK) {
|
---|
| 543 | LWIP_ASSERT("failed to create mem_mutex", 0);
|
---|
| 544 | }
|
---|
| 545 | }
|
---|
| 546 |
|
---|
| 547 | /* Check if a struct mem is correctly linked.
|
---|
| 548 | * If not, double-free is a possible reason.
|
---|
| 549 | */
|
---|
| 550 | static int
|
---|
| 551 | mem_link_valid(struct mem *mem)
|
---|
| 552 | {
|
---|
| 553 | struct mem *nmem, *pmem;
|
---|
| 554 | mem_size_t rmem_idx;
|
---|
| 555 | rmem_idx = mem_to_ptr(mem);
|
---|
| 556 | nmem = ptr_to_mem(mem->next);
|
---|
| 557 | pmem = ptr_to_mem(mem->prev);
|
---|
| 558 | if ((mem->next > MEM_SIZE_ALIGNED) || (mem->prev > MEM_SIZE_ALIGNED) ||
|
---|
| 559 | ((mem->prev != rmem_idx) && (pmem->next != rmem_idx)) ||
|
---|
| 560 | ((nmem != ram_end) && (nmem->prev != rmem_idx))) {
|
---|
| 561 | return 0;
|
---|
| 562 | }
|
---|
| 563 | return 1;
|
---|
| 564 | }
|
---|
| 565 |
|
---|
| 566 | #if MEM_SANITY_CHECK
|
---|
| 567 | static void
|
---|
| 568 | mem_sanity(void)
|
---|
| 569 | {
|
---|
| 570 | struct mem *mem;
|
---|
| 571 | u8_t last_used;
|
---|
| 572 |
|
---|
| 573 | /* begin with first element here */
|
---|
| 574 | mem = (struct mem *)ram;
|
---|
| 575 | LWIP_ASSERT("heap element used valid", (mem->used == 0) || (mem->used == 1));
|
---|
| 576 | last_used = mem->used;
|
---|
| 577 | LWIP_ASSERT("heap element prev ptr valid", mem->prev == 0);
|
---|
| 578 | LWIP_ASSERT("heap element next ptr valid", mem->next <= MEM_SIZE_ALIGNED);
|
---|
| 579 | LWIP_ASSERT("heap element next ptr aligned", LWIP_MEM_ALIGN(ptr_to_mem(mem->next) == ptr_to_mem(mem->next)));
|
---|
| 580 |
|
---|
| 581 | /* check all elements before the end of the heap */
|
---|
| 582 | for (mem = ptr_to_mem(mem->next);
|
---|
| 583 | ((u8_t *)mem > ram) && (mem < ram_end);
|
---|
| 584 | mem = ptr_to_mem(mem->next)) {
|
---|
| 585 | LWIP_ASSERT("heap element aligned", LWIP_MEM_ALIGN(mem) == mem);
|
---|
| 586 | LWIP_ASSERT("heap element prev ptr valid", mem->prev <= MEM_SIZE_ALIGNED);
|
---|
| 587 | LWIP_ASSERT("heap element next ptr valid", mem->next <= MEM_SIZE_ALIGNED);
|
---|
| 588 | LWIP_ASSERT("heap element prev ptr aligned", LWIP_MEM_ALIGN(ptr_to_mem(mem->prev) == ptr_to_mem(mem->prev)));
|
---|
| 589 | LWIP_ASSERT("heap element next ptr aligned", LWIP_MEM_ALIGN(ptr_to_mem(mem->next) == ptr_to_mem(mem->next)));
|
---|
| 590 |
|
---|
| 591 | if (last_used == 0) {
|
---|
| 592 | /* 2 unused elements in a row? */
|
---|
| 593 | LWIP_ASSERT("heap element unused?", mem->used == 1);
|
---|
| 594 | } else {
|
---|
| 595 | LWIP_ASSERT("heap element unused member", (mem->used == 0) || (mem->used == 1));
|
---|
| 596 | }
|
---|
| 597 |
|
---|
| 598 | LWIP_ASSERT("heap element link valid", mem_link_valid(mem));
|
---|
| 599 |
|
---|
| 600 | /* used/unused altering */
|
---|
| 601 | last_used = mem->used;
|
---|
| 602 | }
|
---|
| 603 | LWIP_ASSERT("heap end ptr sanity", mem == ptr_to_mem(MEM_SIZE_ALIGNED));
|
---|
| 604 | LWIP_ASSERT("heap element used valid", mem->used == 1);
|
---|
| 605 | LWIP_ASSERT("heap element prev ptr valid", mem->prev == MEM_SIZE_ALIGNED);
|
---|
| 606 | LWIP_ASSERT("heap element next ptr valid", mem->next == MEM_SIZE_ALIGNED);
|
---|
| 607 | }
|
---|
| 608 | #endif /* MEM_SANITY_CHECK */
|
---|
| 609 |
|
---|
| 610 | /**
|
---|
| 611 | * Put a struct mem back on the heap
|
---|
| 612 | *
|
---|
| 613 | * @param rmem is the data portion of a struct mem as returned by a previous
|
---|
| 614 | * call to mem_malloc()
|
---|
| 615 | */
|
---|
| 616 | void
|
---|
| 617 | mem_free(void *rmem)
|
---|
| 618 | {
|
---|
| 619 | struct mem *mem;
|
---|
| 620 | LWIP_MEM_FREE_DECL_PROTECT();
|
---|
| 621 |
|
---|
| 622 | if (rmem == NULL) {
|
---|
| 623 | LWIP_DEBUGF(MEM_DEBUG | LWIP_DBG_TRACE | LWIP_DBG_LEVEL_SERIOUS, ("mem_free(p == NULL) was called.\n"));
|
---|
| 624 | return;
|
---|
| 625 | }
|
---|
| 626 | if ((((mem_ptr_t)rmem) & (MEM_ALIGNMENT - 1)) != 0) {
|
---|
| 627 | LWIP_MEM_ILLEGAL_FREE("mem_free: sanity check alignment");
|
---|
| 628 | LWIP_DEBUGF(MEM_DEBUG | LWIP_DBG_LEVEL_SEVERE, ("mem_free: sanity check alignment\n"));
|
---|
| 629 | /* protect mem stats from concurrent access */
|
---|
| 630 | MEM_STATS_INC_LOCKED(illegal);
|
---|
| 631 | return;
|
---|
| 632 | }
|
---|
| 633 |
|
---|
| 634 | /* Get the corresponding struct mem: */
|
---|
| 635 | /* cast through void* to get rid of alignment warnings */
|
---|
| 636 | mem = (struct mem *)(void *)((u8_t *)rmem - (SIZEOF_STRUCT_MEM + MEM_SANITY_OFFSET));
|
---|
| 637 |
|
---|
| 638 | if ((u8_t *)mem < ram || (u8_t *)rmem + MIN_SIZE_ALIGNED > (u8_t *)ram_end) {
|
---|
| 639 | LWIP_MEM_ILLEGAL_FREE("mem_free: illegal memory");
|
---|
| 640 | LWIP_DEBUGF(MEM_DEBUG | LWIP_DBG_LEVEL_SEVERE, ("mem_free: illegal memory\n"));
|
---|
| 641 | /* protect mem stats from concurrent access */
|
---|
| 642 | MEM_STATS_INC_LOCKED(illegal);
|
---|
| 643 | return;
|
---|
| 644 | }
|
---|
| 645 | #if MEM_OVERFLOW_CHECK
|
---|
| 646 | mem_overflow_check_element(mem);
|
---|
| 647 | #endif
|
---|
| 648 | /* protect the heap from concurrent access */
|
---|
| 649 | LWIP_MEM_FREE_PROTECT();
|
---|
| 650 | /* mem has to be in a used state */
|
---|
| 651 | if (!mem->used) {
|
---|
| 652 | LWIP_MEM_ILLEGAL_FREE("mem_free: illegal memory: double free");
|
---|
| 653 | LWIP_MEM_FREE_UNPROTECT();
|
---|
| 654 | LWIP_DEBUGF(MEM_DEBUG | LWIP_DBG_LEVEL_SEVERE, ("mem_free: illegal memory: double free?\n"));
|
---|
| 655 | /* protect mem stats from concurrent access */
|
---|
| 656 | MEM_STATS_INC_LOCKED(illegal);
|
---|
| 657 | return;
|
---|
| 658 | }
|
---|
| 659 |
|
---|
| 660 | if (!mem_link_valid(mem)) {
|
---|
| 661 | LWIP_MEM_ILLEGAL_FREE("mem_free: illegal memory: non-linked: double free");
|
---|
| 662 | LWIP_MEM_FREE_UNPROTECT();
|
---|
| 663 | LWIP_DEBUGF(MEM_DEBUG | LWIP_DBG_LEVEL_SEVERE, ("mem_free: illegal memory: non-linked: double free?\n"));
|
---|
| 664 | /* protect mem stats from concurrent access */
|
---|
| 665 | MEM_STATS_INC_LOCKED(illegal);
|
---|
| 666 | return;
|
---|
| 667 | }
|
---|
| 668 |
|
---|
| 669 | /* mem is now unused. */
|
---|
| 670 | mem->used = 0;
|
---|
| 671 |
|
---|
| 672 | if (mem < lfree) {
|
---|
| 673 | /* the newly freed struct is now the lowest */
|
---|
| 674 | lfree = mem;
|
---|
| 675 | }
|
---|
| 676 |
|
---|
| 677 | MEM_STATS_DEC_USED(used, mem->next - (mem_size_t)(((u8_t *)mem - ram)));
|
---|
| 678 |
|
---|
| 679 | /* finally, see if prev or next are free also */
|
---|
| 680 | plug_holes(mem);
|
---|
| 681 | MEM_SANITY();
|
---|
| 682 | #if LWIP_ALLOW_MEM_FREE_FROM_OTHER_CONTEXT
|
---|
| 683 | mem_free_count = 1;
|
---|
| 684 | #endif /* LWIP_ALLOW_MEM_FREE_FROM_OTHER_CONTEXT */
|
---|
| 685 | LWIP_MEM_FREE_UNPROTECT();
|
---|
| 686 | }
|
---|
| 687 |
|
---|
| 688 | /**
|
---|
| 689 | * Shrink memory returned by mem_malloc().
|
---|
| 690 | *
|
---|
| 691 | * @param rmem pointer to memory allocated by mem_malloc the is to be shrinked
|
---|
| 692 | * @param new_size required size after shrinking (needs to be smaller than or
|
---|
| 693 | * equal to the previous size)
|
---|
| 694 | * @return for compatibility reasons: is always == rmem, at the moment
|
---|
| 695 | * or NULL if newsize is > old size, in which case rmem is NOT touched
|
---|
| 696 | * or freed!
|
---|
| 697 | */
|
---|
| 698 | void *
|
---|
| 699 | mem_trim(void *rmem, mem_size_t new_size)
|
---|
| 700 | {
|
---|
| 701 | mem_size_t size, newsize;
|
---|
| 702 | mem_size_t ptr, ptr2;
|
---|
| 703 | struct mem *mem, *mem2;
|
---|
| 704 | /* use the FREE_PROTECT here: it protects with sem OR SYS_ARCH_PROTECT */
|
---|
| 705 | LWIP_MEM_FREE_DECL_PROTECT();
|
---|
| 706 |
|
---|
| 707 | /* Expand the size of the allocated memory region so that we can
|
---|
| 708 | adjust for alignment. */
|
---|
| 709 | newsize = (mem_size_t)LWIP_MEM_ALIGN_SIZE(new_size);
|
---|
| 710 | if (newsize < MIN_SIZE_ALIGNED) {
|
---|
| 711 | /* every data block must be at least MIN_SIZE_ALIGNED long */
|
---|
| 712 | newsize = MIN_SIZE_ALIGNED;
|
---|
| 713 | }
|
---|
| 714 | #if MEM_OVERFLOW_CHECK
|
---|
| 715 | newsize += MEM_SANITY_REGION_BEFORE_ALIGNED + MEM_SANITY_REGION_AFTER_ALIGNED;
|
---|
| 716 | #endif
|
---|
| 717 | if ((newsize > MEM_SIZE_ALIGNED) || (newsize < new_size)) {
|
---|
| 718 | return NULL;
|
---|
| 719 | }
|
---|
| 720 |
|
---|
| 721 | LWIP_ASSERT("mem_trim: legal memory", (u8_t *)rmem >= (u8_t *)ram &&
|
---|
| 722 | (u8_t *)rmem < (u8_t *)ram_end);
|
---|
| 723 |
|
---|
| 724 | if ((u8_t *)rmem < (u8_t *)ram || (u8_t *)rmem >= (u8_t *)ram_end) {
|
---|
| 725 | LWIP_DEBUGF(MEM_DEBUG | LWIP_DBG_LEVEL_SEVERE, ("mem_trim: illegal memory\n"));
|
---|
| 726 | /* protect mem stats from concurrent access */
|
---|
| 727 | MEM_STATS_INC_LOCKED(illegal);
|
---|
| 728 | return rmem;
|
---|
| 729 | }
|
---|
| 730 | /* Get the corresponding struct mem ... */
|
---|
| 731 | /* cast through void* to get rid of alignment warnings */
|
---|
| 732 | mem = (struct mem *)(void *)((u8_t *)rmem - (SIZEOF_STRUCT_MEM + MEM_SANITY_OFFSET));
|
---|
| 733 | #if MEM_OVERFLOW_CHECK
|
---|
| 734 | mem_overflow_check_element(mem);
|
---|
| 735 | #endif
|
---|
| 736 | /* ... and its offset pointer */
|
---|
| 737 | ptr = mem_to_ptr(mem);
|
---|
| 738 |
|
---|
| 739 | size = (mem_size_t)((mem_size_t)(mem->next - ptr) - (SIZEOF_STRUCT_MEM + MEM_SANITY_OVERHEAD));
|
---|
| 740 | LWIP_ASSERT("mem_trim can only shrink memory", newsize <= size);
|
---|
| 741 | if (newsize > size) {
|
---|
| 742 | /* not supported */
|
---|
| 743 | return NULL;
|
---|
| 744 | }
|
---|
| 745 | if (newsize == size) {
|
---|
| 746 | /* No change in size, simply return */
|
---|
| 747 | return rmem;
|
---|
| 748 | }
|
---|
| 749 |
|
---|
| 750 | /* protect the heap from concurrent access */
|
---|
| 751 | LWIP_MEM_FREE_PROTECT();
|
---|
| 752 |
|
---|
| 753 | mem2 = ptr_to_mem(mem->next);
|
---|
| 754 | if (mem2->used == 0) {
|
---|
| 755 | /* The next struct is unused, we can simply move it at little */
|
---|
| 756 | mem_size_t next;
|
---|
| 757 | LWIP_ASSERT("invalid next ptr", mem->next != MEM_SIZE_ALIGNED);
|
---|
| 758 | /* remember the old next pointer */
|
---|
| 759 | next = mem2->next;
|
---|
| 760 | /* create new struct mem which is moved directly after the shrinked mem */
|
---|
| 761 | ptr2 = (mem_size_t)(ptr + SIZEOF_STRUCT_MEM + newsize);
|
---|
| 762 | if (lfree == mem2) {
|
---|
| 763 | lfree = ptr_to_mem(ptr2);
|
---|
| 764 | }
|
---|
| 765 | mem2 = ptr_to_mem(ptr2);
|
---|
| 766 | mem2->used = 0;
|
---|
| 767 | /* restore the next pointer */
|
---|
| 768 | mem2->next = next;
|
---|
| 769 | /* link it back to mem */
|
---|
| 770 | mem2->prev = ptr;
|
---|
| 771 | /* link mem to it */
|
---|
| 772 | mem->next = ptr2;
|
---|
| 773 | /* last thing to restore linked list: as we have moved mem2,
|
---|
| 774 | * let 'mem2->next->prev' point to mem2 again. but only if mem2->next is not
|
---|
| 775 | * the end of the heap */
|
---|
| 776 | if (mem2->next != MEM_SIZE_ALIGNED) {
|
---|
| 777 | ptr_to_mem(mem2->next)->prev = ptr2;
|
---|
| 778 | }
|
---|
| 779 | MEM_STATS_DEC_USED(used, (size - newsize));
|
---|
| 780 | /* no need to plug holes, we've already done that */
|
---|
| 781 | } else if (newsize + SIZEOF_STRUCT_MEM + MIN_SIZE_ALIGNED <= size) {
|
---|
| 782 | /* Next struct is used but there's room for another struct mem with
|
---|
| 783 | * at least MIN_SIZE_ALIGNED of data.
|
---|
| 784 | * Old size ('size') must be big enough to contain at least 'newsize' plus a struct mem
|
---|
| 785 | * ('SIZEOF_STRUCT_MEM') with some data ('MIN_SIZE_ALIGNED').
|
---|
| 786 | * @todo we could leave out MIN_SIZE_ALIGNED. We would create an empty
|
---|
| 787 | * region that couldn't hold data, but when mem->next gets freed,
|
---|
| 788 | * the 2 regions would be combined, resulting in more free memory */
|
---|
| 789 | ptr2 = (mem_size_t)(ptr + SIZEOF_STRUCT_MEM + newsize);
|
---|
| 790 | LWIP_ASSERT("invalid next ptr", mem->next != MEM_SIZE_ALIGNED);
|
---|
| 791 | mem2 = ptr_to_mem(ptr2);
|
---|
| 792 | if (mem2 < lfree) {
|
---|
| 793 | lfree = mem2;
|
---|
| 794 | }
|
---|
| 795 | mem2->used = 0;
|
---|
| 796 | mem2->next = mem->next;
|
---|
| 797 | mem2->prev = ptr;
|
---|
| 798 | mem->next = ptr2;
|
---|
| 799 | if (mem2->next != MEM_SIZE_ALIGNED) {
|
---|
| 800 | ptr_to_mem(mem2->next)->prev = ptr2;
|
---|
| 801 | }
|
---|
| 802 | MEM_STATS_DEC_USED(used, (size - newsize));
|
---|
| 803 | /* the original mem->next is used, so no need to plug holes! */
|
---|
| 804 | }
|
---|
| 805 | /* else {
|
---|
| 806 | next struct mem is used but size between mem and mem2 is not big enough
|
---|
| 807 | to create another struct mem
|
---|
| 808 | -> don't do anyhting.
|
---|
| 809 | -> the remaining space stays unused since it is too small
|
---|
| 810 | } */
|
---|
| 811 | #if MEM_OVERFLOW_CHECK
|
---|
| 812 | mem_overflow_init_element(mem, new_size);
|
---|
| 813 | #endif
|
---|
| 814 | MEM_SANITY();
|
---|
| 815 | #if LWIP_ALLOW_MEM_FREE_FROM_OTHER_CONTEXT
|
---|
| 816 | mem_free_count = 1;
|
---|
| 817 | #endif /* LWIP_ALLOW_MEM_FREE_FROM_OTHER_CONTEXT */
|
---|
| 818 | LWIP_MEM_FREE_UNPROTECT();
|
---|
| 819 | return rmem;
|
---|
| 820 | }
|
---|
| 821 |
|
---|
| 822 | /**
|
---|
| 823 | * Allocate a block of memory with a minimum of 'size' bytes.
|
---|
| 824 | *
|
---|
| 825 | * @param size_in is the minimum size of the requested block in bytes.
|
---|
| 826 | * @return pointer to allocated memory or NULL if no free memory was found.
|
---|
| 827 | *
|
---|
| 828 | * Note that the returned value will always be aligned (as defined by MEM_ALIGNMENT).
|
---|
| 829 | */
|
---|
| 830 | void *
|
---|
| 831 | mem_malloc(mem_size_t size_in)
|
---|
| 832 | {
|
---|
| 833 | mem_size_t ptr, ptr2, size;
|
---|
| 834 | struct mem *mem, *mem2;
|
---|
| 835 | #if LWIP_ALLOW_MEM_FREE_FROM_OTHER_CONTEXT
|
---|
| 836 | u8_t local_mem_free_count = 0;
|
---|
| 837 | #endif /* LWIP_ALLOW_MEM_FREE_FROM_OTHER_CONTEXT */
|
---|
| 838 | LWIP_MEM_ALLOC_DECL_PROTECT();
|
---|
| 839 |
|
---|
| 840 | if (size_in == 0) {
|
---|
| 841 | return NULL;
|
---|
| 842 | }
|
---|
| 843 |
|
---|
| 844 | /* Expand the size of the allocated memory region so that we can
|
---|
| 845 | adjust for alignment. */
|
---|
| 846 | size = (mem_size_t)LWIP_MEM_ALIGN_SIZE(size_in);
|
---|
| 847 | if (size < MIN_SIZE_ALIGNED) {
|
---|
| 848 | /* every data block must be at least MIN_SIZE_ALIGNED long */
|
---|
| 849 | size = MIN_SIZE_ALIGNED;
|
---|
| 850 | }
|
---|
| 851 | #if MEM_OVERFLOW_CHECK
|
---|
| 852 | size += MEM_SANITY_REGION_BEFORE_ALIGNED + MEM_SANITY_REGION_AFTER_ALIGNED;
|
---|
| 853 | #endif
|
---|
| 854 | if ((size > MEM_SIZE_ALIGNED) || (size < size_in)) {
|
---|
| 855 | return NULL;
|
---|
| 856 | }
|
---|
| 857 |
|
---|
| 858 | /* protect the heap from concurrent access */
|
---|
| 859 | sys_mutex_lock(&mem_mutex);
|
---|
| 860 | LWIP_MEM_ALLOC_PROTECT();
|
---|
| 861 | #if LWIP_ALLOW_MEM_FREE_FROM_OTHER_CONTEXT
|
---|
| 862 | /* run as long as a mem_free disturbed mem_malloc or mem_trim */
|
---|
| 863 | do {
|
---|
| 864 | local_mem_free_count = 0;
|
---|
| 865 | #endif /* LWIP_ALLOW_MEM_FREE_FROM_OTHER_CONTEXT */
|
---|
| 866 |
|
---|
| 867 | /* Scan through the heap searching for a free block that is big enough,
|
---|
| 868 | * beginning with the lowest free block.
|
---|
| 869 | */
|
---|
| 870 | for (ptr = mem_to_ptr(lfree); ptr < MEM_SIZE_ALIGNED - size;
|
---|
| 871 | ptr = ptr_to_mem(ptr)->next) {
|
---|
| 872 | mem = ptr_to_mem(ptr);
|
---|
| 873 | #if LWIP_ALLOW_MEM_FREE_FROM_OTHER_CONTEXT
|
---|
| 874 | mem_free_count = 0;
|
---|
| 875 | LWIP_MEM_ALLOC_UNPROTECT();
|
---|
| 876 | /* allow mem_free or mem_trim to run */
|
---|
| 877 | LWIP_MEM_ALLOC_PROTECT();
|
---|
| 878 | if (mem_free_count != 0) {
|
---|
| 879 | /* If mem_free or mem_trim have run, we have to restart since they
|
---|
| 880 | could have altered our current struct mem. */
|
---|
| 881 | local_mem_free_count = 1;
|
---|
| 882 | break;
|
---|
| 883 | }
|
---|
| 884 | #endif /* LWIP_ALLOW_MEM_FREE_FROM_OTHER_CONTEXT */
|
---|
| 885 |
|
---|
| 886 | if ((!mem->used) &&
|
---|
| 887 | (mem->next - (ptr + SIZEOF_STRUCT_MEM)) >= size) {
|
---|
| 888 | /* mem is not used and at least perfect fit is possible:
|
---|
| 889 | * mem->next - (ptr + SIZEOF_STRUCT_MEM) gives us the 'user data size' of mem */
|
---|
| 890 |
|
---|
| 891 | if (mem->next - (ptr + SIZEOF_STRUCT_MEM) >= (size + SIZEOF_STRUCT_MEM + MIN_SIZE_ALIGNED)) {
|
---|
| 892 | /* (in addition to the above, we test if another struct mem (SIZEOF_STRUCT_MEM) containing
|
---|
| 893 | * at least MIN_SIZE_ALIGNED of data also fits in the 'user data space' of 'mem')
|
---|
| 894 | * -> split large block, create empty remainder,
|
---|
| 895 | * remainder must be large enough to contain MIN_SIZE_ALIGNED data: if
|
---|
| 896 | * mem->next - (ptr + (2*SIZEOF_STRUCT_MEM)) == size,
|
---|
| 897 | * struct mem would fit in but no data between mem2 and mem2->next
|
---|
| 898 | * @todo we could leave out MIN_SIZE_ALIGNED. We would create an empty
|
---|
| 899 | * region that couldn't hold data, but when mem->next gets freed,
|
---|
| 900 | * the 2 regions would be combined, resulting in more free memory
|
---|
| 901 | */
|
---|
| 902 | ptr2 = (mem_size_t)(ptr + SIZEOF_STRUCT_MEM + size);
|
---|
| 903 | LWIP_ASSERT("invalid next ptr",ptr2 != MEM_SIZE_ALIGNED);
|
---|
| 904 | /* create mem2 struct */
|
---|
| 905 | mem2 = ptr_to_mem(ptr2);
|
---|
| 906 | mem2->used = 0;
|
---|
| 907 | mem2->next = mem->next;
|
---|
| 908 | mem2->prev = ptr;
|
---|
| 909 | /* and insert it between mem and mem->next */
|
---|
| 910 | mem->next = ptr2;
|
---|
| 911 | mem->used = 1;
|
---|
| 912 |
|
---|
| 913 | if (mem2->next != MEM_SIZE_ALIGNED) {
|
---|
| 914 | ptr_to_mem(mem2->next)->prev = ptr2;
|
---|
| 915 | }
|
---|
| 916 | MEM_STATS_INC_USED(used, (size + SIZEOF_STRUCT_MEM));
|
---|
| 917 | } else {
|
---|
| 918 | /* (a mem2 struct does no fit into the user data space of mem and mem->next will always
|
---|
| 919 | * be used at this point: if not we have 2 unused structs in a row, plug_holes should have
|
---|
| 920 | * take care of this).
|
---|
| 921 | * -> near fit or exact fit: do not split, no mem2 creation
|
---|
| 922 | * also can't move mem->next directly behind mem, since mem->next
|
---|
| 923 | * will always be used at this point!
|
---|
| 924 | */
|
---|
| 925 | mem->used = 1;
|
---|
| 926 | MEM_STATS_INC_USED(used, mem->next - mem_to_ptr(mem));
|
---|
| 927 | }
|
---|
| 928 | #if LWIP_ALLOW_MEM_FREE_FROM_OTHER_CONTEXT
|
---|
| 929 | mem_malloc_adjust_lfree:
|
---|
| 930 | #endif /* LWIP_ALLOW_MEM_FREE_FROM_OTHER_CONTEXT */
|
---|
| 931 | if (mem == lfree) {
|
---|
| 932 | struct mem *cur = lfree;
|
---|
| 933 | /* Find next free block after mem and update lowest free pointer */
|
---|
| 934 | while (cur->used && cur != ram_end) {
|
---|
| 935 | #if LWIP_ALLOW_MEM_FREE_FROM_OTHER_CONTEXT
|
---|
| 936 | mem_free_count = 0;
|
---|
| 937 | LWIP_MEM_ALLOC_UNPROTECT();
|
---|
| 938 | /* prevent high interrupt latency... */
|
---|
| 939 | LWIP_MEM_ALLOC_PROTECT();
|
---|
| 940 | if (mem_free_count != 0) {
|
---|
| 941 | /* If mem_free or mem_trim have run, we have to restart since they
|
---|
| 942 | could have altered our current struct mem or lfree. */
|
---|
| 943 | goto mem_malloc_adjust_lfree;
|
---|
| 944 | }
|
---|
| 945 | #endif /* LWIP_ALLOW_MEM_FREE_FROM_OTHER_CONTEXT */
|
---|
| 946 | cur = ptr_to_mem(cur->next);
|
---|
| 947 | }
|
---|
| 948 | lfree = cur;
|
---|
| 949 | LWIP_ASSERT("mem_malloc: !lfree->used", ((lfree == ram_end) || (!lfree->used)));
|
---|
| 950 | }
|
---|
| 951 | LWIP_MEM_ALLOC_UNPROTECT();
|
---|
| 952 | sys_mutex_unlock(&mem_mutex);
|
---|
| 953 | LWIP_ASSERT("mem_malloc: allocated memory not above ram_end.",
|
---|
| 954 | (mem_ptr_t)mem + SIZEOF_STRUCT_MEM + size <= (mem_ptr_t)ram_end);
|
---|
| 955 | LWIP_ASSERT("mem_malloc: allocated memory properly aligned.",
|
---|
| 956 | ((mem_ptr_t)mem + SIZEOF_STRUCT_MEM) % MEM_ALIGNMENT == 0);
|
---|
| 957 | LWIP_ASSERT("mem_malloc: sanity check alignment",
|
---|
| 958 | (((mem_ptr_t)mem) & (MEM_ALIGNMENT - 1)) == 0);
|
---|
| 959 |
|
---|
| 960 | #if MEM_OVERFLOW_CHECK
|
---|
| 961 | mem_overflow_init_element(mem, size_in);
|
---|
| 962 | #endif
|
---|
| 963 | MEM_SANITY();
|
---|
| 964 | return (u8_t *)mem + SIZEOF_STRUCT_MEM + MEM_SANITY_OFFSET;
|
---|
| 965 | }
|
---|
| 966 | }
|
---|
| 967 | #if LWIP_ALLOW_MEM_FREE_FROM_OTHER_CONTEXT
|
---|
| 968 | /* if we got interrupted by a mem_free, try again */
|
---|
| 969 | } while (local_mem_free_count != 0);
|
---|
| 970 | #endif /* LWIP_ALLOW_MEM_FREE_FROM_OTHER_CONTEXT */
|
---|
| 971 | MEM_STATS_INC(err);
|
---|
| 972 | LWIP_MEM_ALLOC_UNPROTECT();
|
---|
| 973 | sys_mutex_unlock(&mem_mutex);
|
---|
| 974 | LWIP_DEBUGF(MEM_DEBUG | LWIP_DBG_LEVEL_SERIOUS, ("mem_malloc: could not allocate %"S16_F" bytes\n", (s16_t)size));
|
---|
| 975 | return NULL;
|
---|
| 976 | }
|
---|
| 977 |
|
---|
| 978 | #endif /* MEM_USE_POOLS */
|
---|
| 979 |
|
---|
| 980 | #if MEM_LIBC_MALLOC && (!LWIP_STATS || !MEM_STATS)
|
---|
| 981 | void *
|
---|
| 982 | mem_calloc(mem_size_t count, mem_size_t size)
|
---|
| 983 | {
|
---|
| 984 | return mem_clib_calloc(count, size);
|
---|
| 985 | }
|
---|
| 986 |
|
---|
| 987 | #else /* MEM_LIBC_MALLOC && (!LWIP_STATS || !MEM_STATS) */
|
---|
| 988 | /**
|
---|
| 989 | * Contiguously allocates enough space for count objects that are size bytes
|
---|
| 990 | * of memory each and returns a pointer to the allocated memory.
|
---|
| 991 | *
|
---|
| 992 | * The allocated memory is filled with bytes of value zero.
|
---|
| 993 | *
|
---|
| 994 | * @param count number of objects to allocate
|
---|
| 995 | * @param size size of the objects to allocate
|
---|
| 996 | * @return pointer to allocated memory / NULL pointer if there is an error
|
---|
| 997 | */
|
---|
| 998 | void *
|
---|
| 999 | mem_calloc(mem_size_t count, mem_size_t size)
|
---|
| 1000 | {
|
---|
| 1001 | void *p;
|
---|
| 1002 | size_t alloc_size = (size_t)count * (size_t)size;
|
---|
| 1003 |
|
---|
| 1004 | if ((size_t)(mem_size_t)alloc_size != alloc_size) {
|
---|
| 1005 | LWIP_DEBUGF(MEM_DEBUG | LWIP_DBG_LEVEL_SERIOUS, ("mem_calloc: could not allocate %"SZT_F" bytes\n", alloc_size));
|
---|
| 1006 | return NULL;
|
---|
| 1007 | }
|
---|
| 1008 |
|
---|
| 1009 | /* allocate 'count' objects of size 'size' */
|
---|
| 1010 | p = mem_malloc((mem_size_t)alloc_size);
|
---|
| 1011 | if (p) {
|
---|
| 1012 | /* zero the memory */
|
---|
| 1013 | memset(p, 0, alloc_size);
|
---|
| 1014 | }
|
---|
| 1015 | return p;
|
---|
| 1016 | }
|
---|
| 1017 | #endif /* MEM_LIBC_MALLOC && (!LWIP_STATS || !MEM_STATS) */
|
---|