Danger-alarm/SOFTWARE-FreeRTOS/Common/ethernet/lwIP/core/mem.c
2024-06-03 16:27:41 +08:00

415 lines
11 KiB
C

/** @file
*
* Dynamic memory manager
*
*/
/*
* Copyright (c) 2001-2004 Swedish Institute of Computer Science.
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without modification,
* are permitted provided that the following conditions are met:
*
* 1. Redistributions of source code must retain the above copyright notice,
* this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright notice,
* this list of conditions and the following disclaimer in the documentation
* and/or other materials provided with the distribution.
* 3. The name of the author may not be used to endorse or promote products
* derived from this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR IMPLIED
* WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
* MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT
* SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
* EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT
* OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
* INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
* CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
* IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY
* OF SUCH DAMAGE.
*
* This file is part of the lwIP TCP/IP stack.
*
* Author: Adam Dunkels <adam@sics.se>
*
*/
#include <string.h>
#include "lwip/arch.h"
#include "lwip/opt.h"
#include "lwip/def.h"
#include "lwip/mem.h"
#include "lwip/sys.h"
#include "lwip/stats.h"
#if (MEM_LIBC_MALLOC == 0)
/* lwIP replacement for your libc malloc() */
struct mem {
mem_size_t next, prev;
#if MEM_ALIGNMENT == 1
u8_t used;
#elif MEM_ALIGNMENT == 2
u16_t used;
#elif MEM_ALIGNMENT == 4
u32_t used;
#elif MEM_ALIGNMENT == 8
u64_t used;
#else
#error "unhandled MEM_ALIGNMENT size"
#endif /* MEM_ALIGNMENT */
};
static struct mem *ram_end;
#if 1
/* Adam original */
static u8_t ram[MEM_SIZE + sizeof(struct mem) + MEM_ALIGNMENT];
#else
/* Christiaan alignment fix */
static u8_t *ram;
static struct mem ram_heap[1 + ( (MEM_SIZE + sizeof(struct mem) - 1) / sizeof(struct mem))];
#endif
#define MIN_SIZE 12
#if 0 /* this one does not align correctly for some, resulting in crashes */
#define SIZEOF_STRUCT_MEM (unsigned int)MEM_ALIGN_SIZE(sizeof(struct mem))
#else
#define SIZEOF_STRUCT_MEM (sizeof(struct mem) + \
(((sizeof(struct mem) % MEM_ALIGNMENT) == 0)? 0 : \
(4 - (sizeof(struct mem) % MEM_ALIGNMENT))))
#endif
static struct mem *lfree; /* pointer to the lowest free block */
static sys_sem_t mem_sem;
static void
plug_holes(struct mem *mem)
{
struct mem *nmem;
struct mem *pmem;
LWIP_ASSERT("plug_holes: mem >= ram", (u8_t *)mem >= ram);
LWIP_ASSERT("plug_holes: mem < ram_end", (u8_t *)mem < (u8_t *)ram_end);
LWIP_ASSERT("plug_holes: mem->used == 0", mem->used == 0);
/* plug hole forward */
LWIP_ASSERT("plug_holes: mem->next <= MEM_SIZE", mem->next <= MEM_SIZE);
nmem = (struct mem *)&ram[mem->next];
if (mem != nmem && nmem->used == 0 && (u8_t *)nmem != (u8_t *)ram_end) {
if (lfree == nmem) {
lfree = mem;
}
mem->next = nmem->next;
((struct mem *)&ram[nmem->next])->prev = (u8_t *)mem - ram;
}
/* plug hole backward */
pmem = (struct mem *)&ram[mem->prev];
if (pmem != mem && pmem->used == 0) {
if (lfree == mem) {
lfree = pmem;
}
pmem->next = mem->next;
((struct mem *)&ram[mem->next])->prev = (u8_t *)pmem - ram;
}
}
void
mem_init(void)
{
struct mem *mem;
#if 1
/* Adam original */
#else
/* Christiaan alignment fix */
ram = (u8_t*)ram_heap;
#endif
memset(ram, 0, MEM_SIZE);
mem = (struct mem *)ram;
mem->next = MEM_SIZE;
mem->prev = 0;
mem->used = 0;
ram_end = (struct mem *)&ram[MEM_SIZE];
ram_end->used = 1;
ram_end->next = MEM_SIZE;
ram_end->prev = MEM_SIZE;
mem_sem = sys_sem_new(1);
lfree = (struct mem *)ram;
#if MEM_STATS
lwip_stats.mem.avail = MEM_SIZE;
#endif /* MEM_STATS */
}
void
mem_free(void *rmem)
{
struct mem *mem;
if (rmem == NULL) {
LWIP_DEBUGF(MEM_DEBUG | DBG_TRACE | 2, ("mem_free(p == NULL) was called.\n"));
return;
}
sys_sem_wait(mem_sem);
LWIP_ASSERT("mem_free: legal memory", (u8_t *)rmem >= (u8_t *)ram &&
(u8_t *)rmem < (u8_t *)ram_end);
if ((u8_t *)rmem < (u8_t *)ram || (u8_t *)rmem >= (u8_t *)ram_end) {
LWIP_DEBUGF(MEM_DEBUG | 3, ("mem_free: illegal memory\n"));
#if MEM_STATS
++lwip_stats.mem.err;
#endif /* MEM_STATS */
sys_sem_signal(mem_sem);
return;
}
mem = (struct mem *)((u8_t *)rmem - SIZEOF_STRUCT_MEM);
LWIP_ASSERT("mem_free: mem->used", mem->used);
mem->used = 0;
if (mem < lfree) {
lfree = mem;
}
#if MEM_STATS
lwip_stats.mem.used -= mem->next - ((u8_t *)mem - ram);
#endif /* MEM_STATS */
plug_holes(mem);
sys_sem_signal(mem_sem);
}
void *
mem_realloc(void *rmem, mem_size_t newsize)
{
mem_size_t size;
mem_size_t ptr, ptr2;
struct mem *mem, *mem2;
/* Expand the size of the allocated memory region so that we can
adjust for alignment. */
if ((newsize % MEM_ALIGNMENT) != 0) {
newsize += MEM_ALIGNMENT - ((newsize + SIZEOF_STRUCT_MEM) % MEM_ALIGNMENT);
}
if (newsize > MEM_SIZE) {
return NULL;
}
sys_sem_wait(mem_sem);
LWIP_ASSERT("mem_realloc: legal memory", (u8_t *)rmem >= (u8_t *)ram &&
(u8_t *)rmem < (u8_t *)ram_end);
if ((u8_t *)rmem < (u8_t *)ram || (u8_t *)rmem >= (u8_t *)ram_end) {
LWIP_DEBUGF(MEM_DEBUG | 3, ("mem_realloc: illegal memory\n"));
return rmem;
}
mem = (struct mem *)((u8_t *)rmem - SIZEOF_STRUCT_MEM);
ptr = (u8_t *)mem - ram;
size = mem->next - ptr - SIZEOF_STRUCT_MEM;
#if MEM_STATS
lwip_stats.mem.used -= (size - newsize);
#endif /* MEM_STATS */
if (newsize + SIZEOF_STRUCT_MEM + MIN_SIZE < size) {
ptr2 = ptr + SIZEOF_STRUCT_MEM + newsize;
mem2 = (struct mem *)&ram[ptr2];
mem2->used = 0;
mem2->next = mem->next;
mem2->prev = ptr;
mem->next = ptr2;
if (mem2->next != MEM_SIZE) {
((struct mem *)&ram[mem2->next])->prev = ptr2;
}
plug_holes(mem2);
}
sys_sem_signal(mem_sem);
return rmem;
}
#if 1
/**
* Adam's mem_malloc(), suffers from bug #17922
* Set if to 0 for alternative mem_malloc().
*/
void *
mem_malloc(mem_size_t size)
{
mem_size_t ptr, ptr2;
struct mem *mem, *mem2;
if (size == 0) {
return NULL;
}
/* Expand the size of the allocated memory region so that we can
adjust for alignment. */
if ((size % MEM_ALIGNMENT) != 0) {
size += MEM_ALIGNMENT - ((size + SIZEOF_STRUCT_MEM) % MEM_ALIGNMENT);
}
if (size > MEM_SIZE) {
return NULL;
}
sys_sem_wait(mem_sem);
for (ptr = (u8_t *)lfree - ram; ptr < MEM_SIZE; ptr = ((struct mem *)&ram[ptr])->next) {
mem = (struct mem *)&ram[ptr];
if (!mem->used &&
mem->next - (ptr + SIZEOF_STRUCT_MEM) >= size + SIZEOF_STRUCT_MEM) {
ptr2 = ptr + SIZEOF_STRUCT_MEM + size;
mem2 = (struct mem *)&ram[ptr2];
mem2->prev = ptr;
mem2->next = mem->next;
mem->next = ptr2;
if (mem2->next != MEM_SIZE) {
((struct mem *)&ram[mem2->next])->prev = ptr2;
}
mem2->used = 0;
mem->used = 1;
#if MEM_STATS
lwip_stats.mem.used += (size + SIZEOF_STRUCT_MEM);
/* if (lwip_stats.mem.max < lwip_stats.mem.used) {
lwip_stats.mem.max = lwip_stats.mem.used;
} */
if (lwip_stats.mem.max < ptr2) {
lwip_stats.mem.max = ptr2;
}
#endif /* MEM_STATS */
if (mem == lfree) {
/* Find next free block after mem */
while (lfree->used && lfree != ram_end) {
lfree = (struct mem *)&ram[lfree->next];
}
LWIP_ASSERT("mem_malloc: !lfree->used", !lfree->used);
}
sys_sem_signal(mem_sem);
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.",
(unsigned long)((u8_t *)mem + SIZEOF_STRUCT_MEM) % MEM_ALIGNMENT == 0);
return (u8_t *)mem + SIZEOF_STRUCT_MEM;
}
}
LWIP_DEBUGF(MEM_DEBUG | 2, ("mem_malloc: could not allocate %"S16_F" bytes\n", (s16_t)size));
#if MEM_STATS
++lwip_stats.mem.err;
#endif /* MEM_STATS */
sys_sem_signal(mem_sem);
return NULL;
}
#else
/**
* Adam's mem_malloc() plus solution for bug #17922
*/
void *
mem_malloc(mem_size_t size)
{
mem_size_t ptr, ptr2;
struct mem *mem, *mem2;
if (size == 0) {
return NULL;
}
/* Expand the size of the allocated memory region so that we can
adjust for alignment. */
if ((size % MEM_ALIGNMENT) != 0) {
size += MEM_ALIGNMENT - ((size + SIZEOF_STRUCT_MEM) % MEM_ALIGNMENT);
}
if (size > MEM_SIZE) {
return NULL;
}
sys_sem_wait(mem_sem);
for (ptr = (u8_t *)lfree - ram; ptr < MEM_SIZE - size; ptr = ((struct mem *)&ram[ptr])->next) {
mem = (struct mem *)&ram[ptr];
if (!mem->used) {
ptr2 = ptr + SIZEOF_STRUCT_MEM + size;
if (mem->next - (ptr + (2*SIZEOF_STRUCT_MEM)) >= size) {
/* split large block, create empty remainder */
mem->next = ptr2;
mem->used = 1;
/* create mem2 struct */
mem2 = (struct mem *)&ram[ptr2];
mem2->used = 0;
mem2->next = mem->next;
mem2->prev = ptr;
if (mem2->next != MEM_SIZE) {
((struct mem *)&ram[mem2->next])->prev = ptr2;
}
}
else if (mem->next - (ptr + SIZEOF_STRUCT_MEM) > size) {
/* near fit, no split, no mem2 creation,
round up to mem->next */
ptr2 = mem->next;
mem->used = 1;
}
else if (mem->next - (ptr + SIZEOF_STRUCT_MEM) == size) {
/* exact fit, do not split, no mem2 creation */
mem->next = ptr2;
mem->used = 1;
}
if (mem->used) {
#if MEM_STATS
lwip_stats.mem.used += (size + SIZEOF_STRUCT_MEM);
if (lwip_stats.mem.max < ptr2) {
lwip_stats.mem.max = ptr2;
}
#endif /* MEM_STATS */
if (mem == lfree) {
/* Find next free block after mem */
while (lfree->used && lfree != ram_end) {
lfree = (struct mem *)&ram[lfree->next];
}
LWIP_ASSERT("mem_malloc: !lfree->used", !lfree->used);
}
sys_sem_signal(mem_sem);
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.",
(unsigned long)((u8_t *)mem + SIZEOF_STRUCT_MEM) % MEM_ALIGNMENT == 0);
return (u8_t *)mem + SIZEOF_STRUCT_MEM;
}
}
}
LWIP_DEBUGF(MEM_DEBUG | 2, ("mem_malloc: could not allocate %"S16_F" bytes\n", (s16_t)size));
#if MEM_STATS
++lwip_stats.mem.err;
#endif /* MEM_STATS */
sys_sem_signal(mem_sem);
return NULL;
}
#endif
#endif /* MEM_LIBC_MALLOC == 0 */