www.pudn.com > lwip-1.3.0.rar > memp.c
/**
* @file
* Dynamic pool memory manager
*
* lwIP has dedicated pools for many structures (netconn, protocol control blocks,
* packet buffers, ...). All these pools are managed here.
*/
/*
* 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
*
*/
#include "lwip/opt.h"
#include "lwip/memp.h"
#include "lwip/pbuf.h"
#include "lwip/udp.h"
#include "lwip/raw.h"
#include "lwip/tcp.h"
#include "lwip/igmp.h"
#include "lwip/api.h"
#include "lwip/api_msg.h"
#include "lwip/tcpip.h"
#include "lwip/sys.h"
#include "lwip/stats.h"
#include "netif/etharp.h"
#include "lwip/ip_frag.h"
#include
struct memp {
struct memp *next;
#if MEMP_OVERFLOW_CHECK
const char *file;
int line;
#endif /* MEMP_OVERFLOW_CHECK */
};
#if MEMP_OVERFLOW_CHECK
/* if MEMP_OVERFLOW_CHECK is turned on, we reserve some bytes at the beginning
* and at the end of each element, initialize them as 0xcd and check
* them later. */
/* If MEMP_OVERFLOW_CHECK is >= 2, on every call to memp_malloc or memp_free,
* every single element in each pool is checked!
* This is VERY SLOW but also very helpful. */
/* MEMP_SANITY_REGION_BEFORE and MEMP_SANITY_REGION_AFTER can be overridden in
* lwipopts.h to change the amount reserved for checking. */
#ifndef MEMP_SANITY_REGION_BEFORE
#define MEMP_SANITY_REGION_BEFORE 16
#endif /* MEMP_SANITY_REGION_BEFORE*/
#if MEMP_SANITY_REGION_BEFORE > 0
#define MEMP_SANITY_REGION_BEFORE_ALIGNED LWIP_MEM_ALIGN_SIZE(MEMP_SANITY_REGION_BEFORE)
#else
#define MEMP_SANITY_REGION_BEFORE_ALIGNED 0
#endif /* MEMP_SANITY_REGION_BEFORE*/
#ifndef MEMP_SANITY_REGION_AFTER
#define MEMP_SANITY_REGION_AFTER 16
#endif /* MEMP_SANITY_REGION_AFTER*/
#if MEMP_SANITY_REGION_AFTER > 0
#define MEMP_SANITY_REGION_AFTER_ALIGNED LWIP_MEM_ALIGN_SIZE(MEMP_SANITY_REGION_AFTER)
#else
#define MEMP_SANITY_REGION_AFTER_ALIGNED 0
#endif /* MEMP_SANITY_REGION_AFTER*/
/* MEMP_SIZE: save space for struct memp and for sanity check */
#define MEMP_SIZE (LWIP_MEM_ALIGN_SIZE(sizeof(struct memp)) + MEMP_SANITY_REGION_BEFORE_ALIGNED)
#define MEMP_ALIGN_SIZE(x) (LWIP_MEM_ALIGN_SIZE(x) + MEMP_SANITY_REGION_AFTER_ALIGNED)
#else /* MEMP_OVERFLOW_CHECK */
/* No sanity checks
* We don't need to preserve the struct memp while not allocated, so we
* can save a little space and set MEMP_SIZE to 0.
*/
#define MEMP_SIZE 0
#define MEMP_ALIGN_SIZE(x) (LWIP_MEM_ALIGN_SIZE(x))
#endif /* MEMP_OVERFLOW_CHECK */
/** This array holds the first free element of each pool.
* Elements form a linked list. */
static struct memp *memp_tab[MEMP_MAX];
/** This array holds the element sizes of each pool. */
#if !MEM_USE_POOLS
static
#endif
const u16_t memp_sizes[MEMP_MAX] = {
#define LWIP_MEMPOOL(name,num,size,desc) MEMP_ALIGN_SIZE(size),
#include "lwip/memp_std.h"
};
/** This array holds the number of elements in each pool. */
static const u16_t memp_num[MEMP_MAX] = {
#define LWIP_MEMPOOL(name,num,size,desc) (num),
#include "lwip/memp_std.h"
};
/** This array holds a textual description of each pool. */
#ifdef LWIP_DEBUG
static const char *memp_desc[MEMP_MAX] = {
#define LWIP_MEMPOOL(name,num,size,desc) (desc),
#include "lwip/memp_std.h"
};
#endif /* LWIP_DEBUG */
/** This is the actual memory used by the pools. */
static u8_t memp_memory[MEM_ALIGNMENT - 1
#define LWIP_MEMPOOL(name,num,size,desc) + ( (num) * (MEMP_SIZE + MEMP_ALIGN_SIZE(size) ) )
#include "lwip/memp_std.h"
];
#if MEMP_SANITY_CHECK
/**
* Check that memp-lists don't form a circle
*/
static int
memp_sanity(void)
{
s16_t i, c;
struct memp *m, *n;
for (i = 0; i < MEMP_MAX; i++) {
for (m = memp_tab[i]; m != NULL; m = m->next) {
c = 1;
for (n = memp_tab[i]; n != NULL; n = n->next) {
if (n == m && --c < 0) {
return 0;
}
}
}
}
return 1;
}
#endif /* MEMP_SANITY_CHECK*/
#if MEMP_OVERFLOW_CHECK
/**
* Check if a memp element was victim of an overflow
* (e.g. the restricted area after it has been altered)
*
* @param p the memp element to check
* @param memp_size the element size of the pool p comes from
*/
static void
memp_overflow_check_element(struct memp *p, u16_t memp_size)
{
u16_t k;
u8_t *m;
#if MEMP_SANITY_REGION_BEFORE_ALIGNED > 0
m = (u8_t*)p + MEMP_SIZE - MEMP_SANITY_REGION_BEFORE_ALIGNED;
for (k = 0; k < MEMP_SANITY_REGION_BEFORE_ALIGNED; k++) {
if (m[k] != 0xcd) {
LWIP_ASSERT("detected memp underflow!", 0);
}
}
#endif
#if MEMP_SANITY_REGION_AFTER_ALIGNED > 0
m = (u8_t*)p + MEMP_SIZE + memp_size - MEMP_SANITY_REGION_AFTER_ALIGNED;
for (k = 0; k < MEMP_SANITY_REGION_AFTER_ALIGNED; k++) {
if (m[k] != 0xcd) {
LWIP_ASSERT("detected memp overflow!", 0);
}
}
#endif
}
/**
* Do an overflow check for all elements in every pool.
*
* @see memp_overflow_check_element for a description of the check
*/
static void
memp_overflow_check_all(void)
{
u16_t i, j;
struct memp *p;
p = LWIP_MEM_ALIGN(memp_memory);
for (i = 0; i < MEMP_MAX; ++i) {
p = p;
for (j = 0; j < memp_num[i]; ++j) {
memp_overflow_check_element(p, memp_sizes[i]);
p = (struct memp*)((u8_t*)p + MEMP_SIZE + memp_sizes[i]);
}
}
}
/**
* Initialize the restricted areas of all memp elements in every pool.
*/
static void
memp_overflow_init(void)
{
u16_t i, j;
struct memp *p;
u8_t *m;
p = LWIP_MEM_ALIGN(memp_memory);
for (i = 0; i < MEMP_MAX; ++i) {
p = p;
for (j = 0; j < memp_num[i]; ++j) {
#if MEMP_SANITY_REGION_BEFORE_ALIGNED > 0
m = (u8_t*)p + MEMP_SIZE - MEMP_SANITY_REGION_BEFORE_ALIGNED;
memset(m, 0xcd, MEMP_SANITY_REGION_BEFORE_ALIGNED);
#endif
#if MEMP_SANITY_REGION_AFTER_ALIGNED > 0
m = (u8_t*)p + MEMP_SIZE + memp_sizes[i] - MEMP_SANITY_REGION_AFTER_ALIGNED;
memset(m, 0xcd, MEMP_SANITY_REGION_AFTER_ALIGNED);
#endif
p = (struct memp*)((u8_t*)p + MEMP_SIZE + memp_sizes[i]);
}
}
}
#endif /* MEMP_OVERFLOW_CHECK */
/**
* Initialize this module.
*
* Carves out memp_memory into linked lists for each pool-type.
*/
void
memp_init(void)
{
struct memp *memp;
u16_t i, j;
#if MEMP_STATS
for (i = 0; i < MEMP_MAX; ++i) {
lwip_stats.memp[i].used = lwip_stats.memp[i].max =
lwip_stats.memp[i].err = 0;
lwip_stats.memp[i].avail = memp_num[i];
}
#endif /* MEMP_STATS */
memp = LWIP_MEM_ALIGN(memp_memory);
/* for every pool: */
for (i = 0; i < MEMP_MAX; ++i) {
memp_tab[i] = NULL;
/* create a linked list of memp elements */
for (j = 0; j < memp_num[i]; ++j) {
memp->next = memp_tab[i];
memp_tab[i] = memp;
memp = (struct memp *)((u8_t *)memp + MEMP_SIZE + memp_sizes[i]);
}
}
#if MEMP_OVERFLOW_CHECK
memp_overflow_init();
/* check everything a first time to see if it worked */
memp_overflow_check_all();
#endif /* MEMP_OVERFLOW_CHECK */
}
/**
* Get an element from a specific pool.
*
* @param type the pool to get an element from
*
* the debug version has two more parameters:
* @param file file name calling this function
* @param line number of line where this function is called
*
* @return a pointer to the allocated memory or a NULL pointer on error
*/
void *
#if !MEMP_OVERFLOW_CHECK
memp_malloc(memp_t type)
#else
memp_malloc_fn(memp_t type, const char* file, const int line)
#endif
{
struct memp *memp;
SYS_ARCH_DECL_PROTECT(old_level);
LWIP_ERROR("memp_malloc: type < MEMP_MAX", (type < MEMP_MAX), return NULL;);
SYS_ARCH_PROTECT(old_level);
#if MEMP_OVERFLOW_CHECK >= 2
memp_overflow_check_all();
#endif /* MEMP_OVERFLOW_CHECK >= 2 */
memp = memp_tab[type];
if (memp != NULL) {
memp_tab[type] = memp->next;
#if MEMP_OVERFLOW_CHECK
memp->next = NULL;
memp->file = file;
memp->line = line;
#endif /* MEMP_OVERFLOW_CHECK */
#if MEMP_STATS
++lwip_stats.memp[type].used;
if (lwip_stats.memp[type].used > lwip_stats.memp[type].max) {
lwip_stats.memp[type].max = lwip_stats.memp[type].used;
}
#endif /* MEMP_STATS */
LWIP_ASSERT("memp_malloc: memp properly aligned",
((mem_ptr_t)memp % MEM_ALIGNMENT) == 0);
memp = (struct memp*)((u8_t*)memp + MEMP_SIZE);
} else {
LWIP_DEBUGF(MEMP_DEBUG | 2, ("memp_malloc: out of memory in pool %s\n", memp_desc[type]));
#if MEMP_STATS
++lwip_stats.memp[type].err;
#endif /* MEMP_STATS */
}
SYS_ARCH_UNPROTECT(old_level);
return memp;
}
/**
* Put an element back into its pool.
*
* @param type the pool where to put mem
* @param mem the memp element to free
*/
void
memp_free(memp_t type, void *mem)
{
struct memp *memp;
SYS_ARCH_DECL_PROTECT(old_level);
if (mem == NULL) {
return;
}
LWIP_ASSERT("memp_free: mem properly aligned",
((mem_ptr_t)mem % MEM_ALIGNMENT) == 0);
memp = (struct memp *)((u8_t*)mem - MEMP_SIZE);
SYS_ARCH_PROTECT(old_level);
#if MEMP_OVERFLOW_CHECK
#if MEMP_OVERFLOW_CHECK >= 2
memp_overflow_check_all();
#else
memp_overflow_check_element(memp, memp_sizes[type]);
#endif /* MEMP_OVERFLOW_CHECK >= 2 */
#endif /* MEMP_OVERFLOW_CHECK */
#if MEMP_STATS
lwip_stats.memp[type].used--;
#endif /* MEMP_STATS */
memp->next = memp_tab[type];
memp_tab[type] = memp;
#if MEMP_SANITY_CHECK
LWIP_ASSERT("memp sanity", memp_sanity());
#endif /* MEMP_SANITY_CHECK */
SYS_ARCH_UNPROTECT(old_level);
}