645 lines
22 KiB
C
645 lines
22 KiB
C
/**
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* @file
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* Dynamic memory manager
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*
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* This is a lightweight replacement for the standard C library malloc().
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*
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* If you want to use the standard C library malloc() instead, define
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* MEM_LIBC_MALLOC to 1 in your lwipopts.h
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*
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* To let mem_malloc() use pools (prevents fragmentation and is much faster than
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* a heap but might waste some memory), define MEM_USE_POOLS to 1, define
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* MEM_USE_CUSTOM_POOLS to 1 and create a file "lwippools.h" that includes a list
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* of pools like this (more pools can be added between _START and _END):
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*
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* Define three pools with sizes 256, 512, and 1512 bytes
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* LWIP_MALLOC_MEMPOOL_START
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* LWIP_MALLOC_MEMPOOL(20, 256)
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* LWIP_MALLOC_MEMPOOL(10, 512)
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* LWIP_MALLOC_MEMPOOL(5, 1512)
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* LWIP_MALLOC_MEMPOOL_END
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*/
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/*
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* Copyright (c) 2001-2004 Swedish Institute of Computer Science.
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* All rights reserved.
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*
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* Redistribution and use in source and binary forms, with or without modification,
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* are permitted provided that the following conditions are met:
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*
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* 1. Redistributions of source code must retain the above copyright notice,
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* this list of conditions and the following disclaimer.
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* 2. Redistributions in binary form must reproduce the above copyright notice,
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* this list of conditions and the following disclaimer in the documentation
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* and/or other materials provided with the distribution.
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* 3. The name of the author may not be used to endorse or promote products
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* derived from this software without specific prior written permission.
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*
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* THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR IMPLIED
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* WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
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* MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT
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* SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
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* EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT
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* OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
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* INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
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* CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
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* IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY
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* OF SUCH DAMAGE.
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*
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* This file is part of the lwIP TCP/IP stack.
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*
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* Author: Adam Dunkels <adam@sics.se>
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* Simon Goldschmidt
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*
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*/
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#include "lwip/opt.h"
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#if !MEM_LIBC_MALLOC /* don't build if not configured for use in lwipopts.h */
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#include "lwip/def.h"
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#include "lwip/mem.h"
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#include "lwip/sys.h"
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#include "lwip/stats.h"
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#include "lwip/err.h"
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#include <string.h>
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#if MEM_USE_POOLS
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/* lwIP head implemented with different sized pools */
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/**
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* Allocate memory: determine the smallest pool that is big enough
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* to contain an element of 'size' and get an element from that pool.
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*
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* @param size the size in bytes of the memory needed
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* @return a pointer to the allocated memory or NULL if the pool is empty
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*/
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void *
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mem_malloc(mem_size_t size)
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{
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struct memp_malloc_helper *element;
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memp_t poolnr;
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mem_size_t required_size = size + sizeof(struct memp_malloc_helper);
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for (poolnr = MEMP_POOL_FIRST; poolnr <= MEMP_POOL_LAST; poolnr = (memp_t)(poolnr + 1)) {
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#if MEM_USE_POOLS_TRY_BIGGER_POOL
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again:
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#endif /* MEM_USE_POOLS_TRY_BIGGER_POOL */
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/* is this pool big enough to hold an element of the required size
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plus a struct memp_malloc_helper that saves the pool this element came from? */
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if (required_size <= memp_sizes[poolnr]) {
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break;
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}
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}
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if (poolnr > MEMP_POOL_LAST) {
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LWIP_ASSERT("mem_malloc(): no pool is that big!", 0);
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return NULL;
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}
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element = (struct memp_malloc_helper*)memp_malloc(poolnr);
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if (element == NULL) {
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/* No need to DEBUGF or ASSERT: This error is already
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taken care of in memp.c */
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#if MEM_USE_POOLS_TRY_BIGGER_POOL
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/** Try a bigger pool if this one is empty! */
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if (poolnr < MEMP_POOL_LAST) {
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poolnr++;
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goto again;
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}
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#endif /* MEM_USE_POOLS_TRY_BIGGER_POOL */
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return NULL;
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}
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/* save the pool number this element came from */
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element->poolnr = poolnr;
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/* and return a pointer to the memory directly after the struct memp_malloc_helper */
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element++;
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return element;
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}
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/**
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* Free memory previously allocated by mem_malloc. Loads the pool number
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* and calls memp_free with that pool number to put the element back into
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* its pool
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*
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* @param rmem the memory element to free
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*/
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void
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mem_free(void *rmem)
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{
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struct memp_malloc_helper *hmem = (struct memp_malloc_helper*)rmem;
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LWIP_ASSERT("rmem != NULL", (rmem != NULL));
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LWIP_ASSERT("rmem == MEM_ALIGN(rmem)", (rmem == LWIP_MEM_ALIGN(rmem)));
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/* get the original struct memp_malloc_helper */
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hmem--;
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LWIP_ASSERT("hmem != NULL", (hmem != NULL));
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LWIP_ASSERT("hmem == MEM_ALIGN(hmem)", (hmem == LWIP_MEM_ALIGN(hmem)));
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LWIP_ASSERT("hmem->poolnr < MEMP_MAX", (hmem->poolnr < MEMP_MAX));
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/* and put it in the pool we saved earlier */
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memp_free(hmem->poolnr, hmem);
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}
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#else /* MEM_USE_POOLS */
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/* lwIP replacement for your libc malloc() */
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/**
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* The heap is made up as a list of structs of this type.
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* This does not have to be aligned since for getting its size,
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* we only use the macro SIZEOF_STRUCT_MEM, which automatically alignes.
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*/
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struct mem {
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/** index (-> ram[next]) of the next struct */
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mem_size_t next;
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/** index (-> ram[prev]) of the previous struct */
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mem_size_t prev;
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/** 1: this area is used; 0: this area is unused */
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u8_t used;
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u8_t pad[3]; /* XXX: pad here instead use global ALIGN */
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} __ATTRIB_PACK;
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/** All allocated blocks will be MIN_SIZE bytes big, at least!
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* MIN_SIZE can be overridden to suit your needs. Smaller values save space,
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* larger values could prevent too small blocks to fragment the RAM too much. */
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#ifndef MIN_SIZE
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#define MIN_SIZE 12
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#endif /* MIN_SIZE */
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/* some alignment macros: we define them here for better source code layout */
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#define MIN_SIZE_ALIGNED LWIP_MEM_ALIGN_SIZE(MIN_SIZE)
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#define SIZEOF_STRUCT_MEM LWIP_MEM_ALIGN_SIZE(sizeof(struct mem))
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#define MEM_SIZE_ALIGNED LWIP_MEM_ALIGN_SIZE(MEM_SIZE)
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/** If you want to relocate the heap to external memory, simply define
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* LWIP_RAM_HEAP_POINTER as a void-pointer to that location.
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* If so, make sure the memory at that location is big enough (see below on
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* how that space is calculated). */
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#ifndef LWIP_RAM_HEAP_POINTER
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/** the heap. we need one struct mem at the end and some room for alignment */
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/* enlarge heap as tx pbuf payload is allocate from heap as well */
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u8_t ram_heap[MEM_SIZE_ALIGNED + (2*SIZEOF_STRUCT_MEM) + MEM_ALIGNMENT] SHMEM_ATTR;
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#define LWIP_RAM_HEAP_POINTER ram_heap
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#endif /* LWIP_RAM_HEAP_POINTER */
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/** pointer to the heap (ram_heap): for alignment, ram is now a pointer instead of an array */
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static u8_t *ram;
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/** the last entry, always unused! */
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static struct mem *ram_end;
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/** pointer to the lowest free block, this is used for faster search */
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static struct mem *lfree;
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/** concurrent access protection */
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//static sys_mutex_t mem_mutex;
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#if LWIP_ALLOW_MEM_FREE_FROM_OTHER_CONTEXT
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static volatile u8_t mem_free_count;
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/* Allow mem_free from other (e.g. interrupt) context */
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#define LWIP_MEM_FREE_DECL_PROTECT() SYS_ARCH_DECL_PROTECT(lev_free)
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#define LWIP_MEM_FREE_PROTECT() SYS_ARCH_PROTECT(lev_free)
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#define LWIP_MEM_FREE_UNPROTECT() SYS_ARCH_UNPROTECT(lev_free)
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#define LWIP_MEM_ALLOC_DECL_PROTECT() SYS_ARCH_DECL_PROTECT(lev_alloc)
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#define LWIP_MEM_ALLOC_PROTECT() SYS_ARCH_PROTECT(lev_alloc)
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#define LWIP_MEM_ALLOC_UNPROTECT() SYS_ARCH_UNPROTECT(lev_alloc)
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#else /* LWIP_ALLOW_MEM_FREE_FROM_OTHER_CONTEXT */
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/* Protect the heap only by using a semaphore */
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#define LWIP_MEM_FREE_DECL_PROTECT()
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#define LWIP_MEM_FREE_PROTECT() sys_mutex_lock(&mem_mutex)
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#define LWIP_MEM_FREE_UNPROTECT() sys_mutex_unlock(&mem_mutex)
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/* mem_malloc is protected using semaphore AND LWIP_MEM_ALLOC_PROTECT */
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#define LWIP_MEM_ALLOC_DECL_PROTECT()
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#define LWIP_MEM_ALLOC_PROTECT()
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#define LWIP_MEM_ALLOC_UNPROTECT()
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#endif /* LWIP_ALLOW_MEM_FREE_FROM_OTHER_CONTEXT */
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/**
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* "Plug holes" by combining adjacent empty struct mems.
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* After this function is through, there should not exist
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* one empty struct mem pointing to another empty struct mem.
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*
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* @param mem this points to a struct mem which just has been freed
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* @internal this function is only called by mem_free() and mem_trim()
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*
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* This assumes access to the heap is protected by the calling function
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* already.
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*/
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static void ICACHE_FLASH_ATTR
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plug_holes(struct mem *mem)
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{
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struct mem *nmem;
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struct mem *pmem;
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LWIP_ASSERT("plug_holes: mem >= ram", (u8_t *)mem >= ram);
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LWIP_ASSERT("plug_holes: mem < ram_end", (u8_t *)mem < (u8_t *)ram_end);
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LWIP_ASSERT("plug_holes: mem->used == 0", mem->used == 0);
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/* plug hole forward */
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LWIP_ASSERT("plug_holes: mem->next <= MEM_SIZE_ALIGNED", mem->next <= MEM_SIZE_ALIGNED);
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nmem = (struct mem *)(void *)&ram[mem->next];
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if (mem != nmem && nmem->used == 0 && (u8_t *)nmem != (u8_t *)ram_end) {
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/* if mem->next is unused and not end of ram, combine mem and mem->next */
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if (lfree == nmem) {
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lfree = mem;
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}
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mem->next = nmem->next;
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((struct mem *)(void *)&ram[nmem->next])->prev = (mem_size_t)((u8_t *)mem - ram);
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}
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/* plug hole backward */
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pmem = (struct mem *)(void *)&ram[mem->prev];
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if (pmem != mem && pmem->used == 0) {
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/* if mem->prev is unused, combine mem and mem->prev */
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if (lfree == mem) {
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lfree = pmem;
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}
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pmem->next = mem->next;
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((struct mem *)(void *)&ram[mem->next])->prev = (mem_size_t)((u8_t *)pmem - ram);
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}
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}
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/**
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* Zero the heap and initialize start, end and lowest-free
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*/
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void
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mem_init(void)
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{
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struct mem *mem;
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LWIP_ASSERT("Sanity check alignment",
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(SIZEOF_STRUCT_MEM & (MEM_ALIGNMENT-1)) == 0);
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/* align the heap */
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ram = (u8_t *)LWIP_MEM_ALIGN(LWIP_RAM_HEAP_POINTER);
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/* initialize the start of the heap */
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mem = (struct mem *)(void *)ram;
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mem->next = MEM_SIZE_ALIGNED;
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mem->prev = 0;
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mem->used = 0;
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/* initialize the end of the heap */
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ram_end = (struct mem *)(void *)&ram[MEM_SIZE_ALIGNED];
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ram_end->used = 1;
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ram_end->next = MEM_SIZE_ALIGNED;
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ram_end->prev = MEM_SIZE_ALIGNED;
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/* initialize the lowest-free pointer to the start of the heap */
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lfree = (struct mem *)(void *)ram;
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MEM_STATS_AVAIL(avail, MEM_SIZE_ALIGNED);
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if(sys_mutex_new(&mem_mutex) != ERR_OK) {
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LWIP_ASSERT("failed to create mem_mutex", 0);
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}
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}
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/**
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* Put a struct mem back on the heap
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*
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* @param rmem is the data portion of a struct mem as returned by a previous
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* call to mem_malloc()
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*/
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void
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mem_free(void *rmem)
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{
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struct mem *mem;
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LWIP_MEM_FREE_DECL_PROTECT();
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if (rmem == NULL) {
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LWIP_DEBUGF(MEM_DEBUG | LWIP_DBG_TRACE | LWIP_DBG_LEVEL_SERIOUS, ("mem_free(p == NULL) was called.\n"));
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return;
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}
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LWIP_ASSERT("mem_free: sanity check alignment", (((mem_ptr_t)rmem) & (MEM_ALIGNMENT-1)) == 0);
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LWIP_ASSERT("mem_free: legal memory", (u8_t *)rmem >= (u8_t *)ram &&
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(u8_t *)rmem < (u8_t *)ram_end);
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if ((u8_t *)rmem < (u8_t *)ram || (u8_t *)rmem >= (u8_t *)ram_end) {
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SYS_ARCH_DECL_PROTECT(lev);
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LWIP_DEBUGF(MEM_DEBUG | LWIP_DBG_LEVEL_SEVERE, ("mem_free: illegal memory\n"));
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/* protect mem stats from concurrent access */
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SYS_ARCH_PROTECT(lev);
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MEM_STATS_INC(illegal);
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SYS_ARCH_UNPROTECT(lev);
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return;
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}
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/* protect the heap from concurrent access */
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LWIP_MEM_FREE_PROTECT();
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/* Get the corresponding struct mem ... */
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mem = (struct mem *)(void *)((u8_t *)rmem - SIZEOF_STRUCT_MEM);
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/* ... which has to be in a used state ... */
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LWIP_ASSERT("mem_free: mem->used", mem->used);
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/* ... and is now unused. */
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mem->used = 0;
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if (mem < lfree) {
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/* the newly freed struct is now the lowest */
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lfree = mem;
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}
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MEM_STATS_DEC_USED(used, mem->next - (mem_size_t)(((u8_t *)mem - ram)));
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/* finally, see if prev or next are free also */
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plug_holes(mem);
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#if LWIP_ALLOW_MEM_FREE_FROM_OTHER_CONTEXT
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mem_free_count = 1;
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#endif /* LWIP_ALLOW_MEM_FREE_FROM_OTHER_CONTEXT */
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LWIP_MEM_FREE_UNPROTECT();
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}
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/**
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* Shrink memory returned by mem_malloc().
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*
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* @param rmem pointer to memory allocated by mem_malloc the is to be shrinked
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* @param newsize required size after shrinking (needs to be smaller than or
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* equal to the previous size)
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* @return for compatibility reasons: is always == rmem, at the moment
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* or NULL if newsize is > old size, in which case rmem is NOT touched
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* or freed!
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*/
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void *
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mem_trim(void *rmem, mem_size_t newsize)
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{
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mem_size_t size;
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mem_size_t ptr, ptr2;
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struct mem *mem, *mem2;
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/* use the FREE_PROTECT here: it protects with sem OR SYS_ARCH_PROTECT */
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LWIP_MEM_FREE_DECL_PROTECT();
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/* Expand the size of the allocated memory region so that we can
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adjust for alignment. */
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newsize = LWIP_MEM_ALIGN_SIZE(newsize);
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if(newsize < MIN_SIZE_ALIGNED) {
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/* every data block must be at least MIN_SIZE_ALIGNED long */
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newsize = MIN_SIZE_ALIGNED;
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}
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if (newsize > MEM_SIZE_ALIGNED) {
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return NULL;
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}
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LWIP_ASSERT("mem_trim: legal memory", (u8_t *)rmem >= (u8_t *)ram &&
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(u8_t *)rmem < (u8_t *)ram_end);
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if ((u8_t *)rmem < (u8_t *)ram || (u8_t *)rmem >= (u8_t *)ram_end) {
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SYS_ARCH_DECL_PROTECT(lev);
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LWIP_DEBUGF(MEM_DEBUG | LWIP_DBG_LEVEL_SEVERE, ("mem_trim: illegal memory\n"));
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/* protect mem stats from concurrent access */
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SYS_ARCH_PROTECT(lev);
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MEM_STATS_INC(illegal);
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SYS_ARCH_UNPROTECT(lev);
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return rmem;
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}
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/* Get the corresponding struct mem ... */
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mem = (struct mem *)(void *)((u8_t *)rmem - SIZEOF_STRUCT_MEM);
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/* ... and its offset pointer */
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ptr = (mem_size_t)((u8_t *)mem - ram);
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size = mem->next - ptr - SIZEOF_STRUCT_MEM;
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LWIP_ASSERT("mem_trim can only shrink memory", newsize <= size);
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if (newsize > size) {
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/* not supported */
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return NULL;
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}
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if (newsize == size) {
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/* No change in size, simply return */
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return rmem;
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}
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/* protect the heap from concurrent access */
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LWIP_MEM_FREE_PROTECT();
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mem2 = (struct mem *)(void *)&ram[mem->next];
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if(mem2->used == 0) {
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/* The next struct is unused, we can simply move it at little */
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mem_size_t next;
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/* remember the old next pointer */
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next = mem2->next;
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/* create new struct mem which is moved directly after the shrinked mem */
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ptr2 = ptr + SIZEOF_STRUCT_MEM + newsize;
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if (lfree == mem2) {
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lfree = (struct mem *)(void *)&ram[ptr2];
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}
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mem2 = (struct mem *)(void *)&ram[ptr2];
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mem2->used = 0;
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/* restore the next pointer */
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mem2->next = next;
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/* link it back to mem */
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mem2->prev = ptr;
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/* link mem to it */
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mem->next = ptr2;
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/* last thing to restore linked list: as we have moved mem2,
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* let 'mem2->next->prev' point to mem2 again. but only if mem2->next is not
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* the end of the heap */
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if (mem2->next != MEM_SIZE_ALIGNED) {
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((struct mem *)(void *)&ram[mem2->next])->prev = ptr2;
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}
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MEM_STATS_DEC_USED(used, (size - newsize));
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/* no need to plug holes, we've already done that */
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} else if (newsize + SIZEOF_STRUCT_MEM + MIN_SIZE_ALIGNED <= size) {
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/* Next struct is used but there's room for another struct mem with
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* at least MIN_SIZE_ALIGNED of data.
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* Old size ('size') must be big enough to contain at least 'newsize' plus a struct mem
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* ('SIZEOF_STRUCT_MEM') with some data ('MIN_SIZE_ALIGNED').
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* @todo we could leave out MIN_SIZE_ALIGNED. We would create an empty
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* region that couldn't hold data, but when mem->next gets freed,
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|
* the 2 regions would be combined, resulting in more free memory */
|
|
ptr2 = ptr + SIZEOF_STRUCT_MEM + newsize;
|
|
mem2 = (struct mem *)(void *)&ram[ptr2];
|
|
if (mem2 < lfree) {
|
|
lfree = mem2;
|
|
}
|
|
mem2->used = 0;
|
|
mem2->next = mem->next;
|
|
mem2->prev = ptr;
|
|
mem->next = ptr2;
|
|
if (mem2->next != MEM_SIZE_ALIGNED) {
|
|
((struct mem *)(void *)&ram[mem2->next])->prev = ptr2;
|
|
}
|
|
MEM_STATS_DEC_USED(used, (size - newsize));
|
|
/* the original mem->next is used, so no need to plug holes! */
|
|
}
|
|
/* else {
|
|
next struct mem is used but size between mem and mem2 is not big enough
|
|
to create another struct mem
|
|
-> don't do anyhting.
|
|
-> the remaining space stays unused since it is too small
|
|
} */
|
|
#if LWIP_ALLOW_MEM_FREE_FROM_OTHER_CONTEXT
|
|
mem_free_count = 1;
|
|
#endif /* LWIP_ALLOW_MEM_FREE_FROM_OTHER_CONTEXT */
|
|
LWIP_MEM_FREE_UNPROTECT();
|
|
return rmem;
|
|
}
|
|
|
|
/**
|
|
* Adam's mem_malloc() plus solution for bug #17922
|
|
* Allocate a block of memory with a minimum of 'size' bytes.
|
|
*
|
|
* @param size is the minimum size of the requested block in bytes.
|
|
* @return pointer to allocated memory or NULL if no free memory was found.
|
|
*
|
|
* Note that the returned value will always be aligned (as defined by MEM_ALIGNMENT).
|
|
*/
|
|
void *
|
|
mem_malloc(mem_size_t size)
|
|
{
|
|
mem_size_t ptr, ptr2;
|
|
struct mem *mem, *mem2;
|
|
#if LWIP_ALLOW_MEM_FREE_FROM_OTHER_CONTEXT
|
|
u8_t local_mem_free_count = 0;
|
|
#endif /* LWIP_ALLOW_MEM_FREE_FROM_OTHER_CONTEXT */
|
|
LWIP_MEM_ALLOC_DECL_PROTECT();
|
|
|
|
if (size == 0) {
|
|
return NULL;
|
|
}
|
|
|
|
/* Expand the size of the allocated memory region so that we can
|
|
adjust for alignment. */
|
|
size = LWIP_MEM_ALIGN_SIZE(size);
|
|
|
|
if(size < MIN_SIZE_ALIGNED) {
|
|
/* every data block must be at least MIN_SIZE_ALIGNED long */
|
|
size = MIN_SIZE_ALIGNED;
|
|
}
|
|
|
|
if (size > MEM_SIZE_ALIGNED) {
|
|
return NULL;
|
|
}
|
|
|
|
/* protect the heap from concurrent access */
|
|
sys_mutex_lock(&mem_mutex);
|
|
LWIP_MEM_ALLOC_PROTECT();
|
|
#if LWIP_ALLOW_MEM_FREE_FROM_OTHER_CONTEXT
|
|
/* run as long as a mem_free disturbed mem_malloc */
|
|
do {
|
|
local_mem_free_count = 0;
|
|
#endif /* LWIP_ALLOW_MEM_FREE_FROM_OTHER_CONTEXT */
|
|
|
|
/* Scan through the heap searching for a free block that is big enough,
|
|
* beginning with the lowest free block.
|
|
*/
|
|
for (ptr = (mem_size_t)((u8_t *)lfree - ram); ptr < MEM_SIZE_ALIGNED - size;
|
|
ptr = ((struct mem *)(void *)&ram[ptr])->next) {
|
|
mem = (struct mem *)(void *)&ram[ptr];
|
|
#if LWIP_ALLOW_MEM_FREE_FROM_OTHER_CONTEXT
|
|
mem_free_count = 0;
|
|
LWIP_MEM_ALLOC_UNPROTECT();
|
|
/* allow mem_free to run */
|
|
LWIP_MEM_ALLOC_PROTECT();
|
|
if (mem_free_count != 0) {
|
|
local_mem_free_count = mem_free_count;
|
|
}
|
|
mem_free_count = 0;
|
|
#endif /* LWIP_ALLOW_MEM_FREE_FROM_OTHER_CONTEXT */
|
|
|
|
if ((!mem->used) &&
|
|
(mem->next - (ptr + SIZEOF_STRUCT_MEM)) >= size) {
|
|
/* mem is not used and at least perfect fit is possible:
|
|
* mem->next - (ptr + SIZEOF_STRUCT_MEM) gives us the 'user data size' of mem */
|
|
|
|
if (mem->next - (ptr + SIZEOF_STRUCT_MEM) >= (size + SIZEOF_STRUCT_MEM + MIN_SIZE_ALIGNED)) {
|
|
/* (in addition to the above, we test if another struct mem (SIZEOF_STRUCT_MEM) containing
|
|
* at least MIN_SIZE_ALIGNED of data also fits in the 'user data space' of 'mem')
|
|
* -> split large block, create empty remainder,
|
|
* remainder must be large enough to contain MIN_SIZE_ALIGNED data: if
|
|
* mem->next - (ptr + (2*SIZEOF_STRUCT_MEM)) == size,
|
|
* struct mem would fit in but no data between mem2 and mem2->next
|
|
* @todo we could leave out MIN_SIZE_ALIGNED. We would create an empty
|
|
* region that couldn't hold data, but when mem->next gets freed,
|
|
* the 2 regions would be combined, resulting in more free memory
|
|
*/
|
|
ptr2 = ptr + SIZEOF_STRUCT_MEM + size;
|
|
/* create mem2 struct */
|
|
mem2 = (struct mem *)(void *)&ram[ptr2];
|
|
mem2->used = 0;
|
|
mem2->next = mem->next;
|
|
mem2->prev = ptr;
|
|
/* and insert it between mem and mem->next */
|
|
mem->next = ptr2;
|
|
mem->used = 1;
|
|
|
|
if (mem2->next != MEM_SIZE_ALIGNED) {
|
|
((struct mem *)(void *)&ram[mem2->next])->prev = ptr2;
|
|
}
|
|
MEM_STATS_INC_USED(used, (size + SIZEOF_STRUCT_MEM));
|
|
} else {
|
|
/* (a mem2 struct does no fit into the user data space of mem and mem->next will always
|
|
* be used at this point: if not we have 2 unused structs in a row, plug_holes should have
|
|
* take care of this).
|
|
* -> near fit or excact fit: do not split, no mem2 creation
|
|
* also can't move mem->next directly behind mem, since mem->next
|
|
* will always be used at this point!
|
|
*/
|
|
mem->used = 1;
|
|
MEM_STATS_INC_USED(used, mem->next - (mem_size_t)((u8_t *)mem - ram));
|
|
}
|
|
|
|
if (mem == lfree) {
|
|
/* Find next free block after mem and update lowest free pointer */
|
|
while (lfree->used && lfree != ram_end) {
|
|
LWIP_MEM_ALLOC_UNPROTECT();
|
|
/* prevent high interrupt latency... */
|
|
LWIP_MEM_ALLOC_PROTECT();
|
|
lfree = (struct mem *)(void *)&ram[lfree->next];
|
|
}
|
|
LWIP_ASSERT("mem_malloc: !lfree->used", ((lfree == ram_end) || (!lfree->used)));
|
|
}
|
|
LWIP_MEM_ALLOC_UNPROTECT();
|
|
sys_mutex_unlock(&mem_mutex);
|
|
LWIP_ASSERT("mem_malloc: allocated memory not above ram_end.",
|
|
(mem_ptr_t)mem + SIZEOF_STRUCT_MEM + size <= (mem_ptr_t)ram_end);
|
|
LWIP_ASSERT("mem_malloc: allocated memory properly aligned.",
|
|
((mem_ptr_t)mem + SIZEOF_STRUCT_MEM) % MEM_ALIGNMENT == 0);
|
|
LWIP_ASSERT("mem_malloc: sanity check alignment",
|
|
(((mem_ptr_t)mem) & (MEM_ALIGNMENT-1)) == 0);
|
|
|
|
return (u8_t *)mem + SIZEOF_STRUCT_MEM;
|
|
}
|
|
}
|
|
#if LWIP_ALLOW_MEM_FREE_FROM_OTHER_CONTEXT
|
|
/* if we got interrupted by a mem_free, try again */
|
|
} while(local_mem_free_count != 0);
|
|
#endif /* LWIP_ALLOW_MEM_FREE_FROM_OTHER_CONTEXT */
|
|
LWIP_DEBUGF(MEM_DEBUG | LWIP_DBG_LEVEL_SERIOUS, ("mem_malloc: could not allocate %"S16_F" bytes\n", (s16_t)size));
|
|
MEM_STATS_INC(err);
|
|
LWIP_MEM_ALLOC_UNPROTECT();
|
|
sys_mutex_unlock(&mem_mutex);
|
|
return NULL;
|
|
}
|
|
|
|
#endif /* MEM_USE_POOLS */
|
|
/**
|
|
* Contiguously allocates enough space for count objects that are size bytes
|
|
* of memory each and returns a pointer to the allocated memory.
|
|
*
|
|
* The allocated memory is filled with bytes of value zero.
|
|
*
|
|
* @param count number of objects to allocate
|
|
* @param size size of the objects to allocate
|
|
* @return pointer to allocated memory / NULL pointer if there is an error
|
|
*/
|
|
void *mem_calloc(mem_size_t count, mem_size_t size)
|
|
{
|
|
void *p;
|
|
|
|
/* allocate 'count' objects of size 'size' */
|
|
p = mem_malloc(count * size);
|
|
if (p) {
|
|
/* zero the memory */
|
|
os_memset(p, 0, count * size);
|
|
}
|
|
return p;
|
|
}
|
|
|
|
#endif /* !MEM_LIBC_MALLOC */
|