memory.c

MPEG-4编解码的实现(包括MPEG4视音频编解码)

/*
 * FILE:    memory.c
 * AUTHORS:  Isidor Kouvelas / Colin Perkins / Mark Handley / Orion Hodson
 *
 * $Revision: 1.5 $
 * $Date: 2002/06/12 17:37:25 $
 *
 * Copyright (c) 1995-2000 University College London
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, is 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. All advertising materials mentioning features or use of this software
 *    must display the following acknowledgement:
 *      This product includes software developed by the Computer Science
 *      Department at University College London
 * 4. Neither the name of the University nor of the Department may be used
 *    to endorse or promote products derived from this software without
 *    specific prior written permission.
 * THIS SOFTWARE IS PROVIDED BY THE AUTHORS AND CONTRIBUTORS ``AS IS'' AND
 * ANY EXPRESSED 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 AUTHORS OR CONTRIBUTORS 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.
 */

#include "config_unix.h"
#include "config_win32.h"
#include "debug.h"
#include "memory.h"
#include "util.h"

#ifdef DEBUG_MEM

/* Custom memory routines are here, down to #else, defaults follow */

#define MAX_ADDRS         65536
#define MAGIC_MEMORY      0xdeadbeef
#define MAGIC_MEMORY_SIZE 4

/* Allocated block format is:
 * <chk_header> <memory chunk...> <trailing magic number>
 */

typedef struct {
        uint32_t key;   /* Original allocation number   */
        uint32_t size;  /* Size of allocation requested */
        uint32_t pad;   /* Alignment padding to 8 bytes */
        uint32_t magic; /* Magic number                 */
} chk_header;

typedef struct s_alloc_blk {
        uint32_t    key;     /* Key in table (ascending) */
        chk_header *addr;
        char       *filen;   /* file where allocated     */
        int         line;    /* line where allocated     */
        size_t      length;  /* size of allocation       */
        int         blen;    /* size passed to block_alloc (if relevent) */
        int         est;     /* time last touched in order of all allocation and reclaims */
} alloc_blk;

/* Table is ordered by key */
static alloc_blk mem_item[MAX_ADDRS];

static int   naddr = 0; /* number of allocations */
static int   tick  = 1; /* xmemchk assumes this is one, do not change without checking why */

static int   init  = 0;

/**
 * xdoneinit:
 * @void: 
 * 
 * Marks end of an applications initialization period.  For media
 * applications with real-time data transfer it's sometimes helpful to
 * distinguish between memory allocated during application
 * initialization and when application is running.
 **/

void xdoneinit(void) 
{
	init = tick++;
}

extern int chk_header_okay(const chk_header *ch);
int chk_header_okay(const chk_header *ch)
{
        const uint8_t *tm; /* tail magic */
        ASSERT(ch != NULL);

        if (ch->key == MAGIC_MEMORY) {
                fprintf(stderr, "ERROR: freed unit being checked\n");
                abort();
        }

        tm = (const uint8_t*)ch;
        tm += sizeof(chk_header) + ch->size;

        if (ch->magic != MAGIC_MEMORY) {
                fprintf(stderr, "ERROR: memory underrun\n");
                abort();
                return FALSE;
        } else if (memcmp(tm, &ch->magic, MAGIC_MEMORY_SIZE)) {
                fprintf(stderr, "ERROR: memory overrun\n");
                abort();
                return FALSE;
        }

        return TRUE;
}

static int mem_key_cmp(const void *a, const void *b) {
        const alloc_blk *g, *h;
        g = (const alloc_blk*)a;
        h = (const alloc_blk*)b;
        if (g->key < h->key) {
                return -1;
        } else if (g->key > h->key) {
                return +1;
        }
        return 0;
}

static alloc_blk *mem_item_find(uint32_t key) {
        void      *p;
        alloc_blk  t;
        t.key = key;
        p = bsearch((const void*)&t, mem_item, naddr, sizeof(alloc_blk), mem_key_cmp);
        return (alloc_blk*)p;
}

/**
 * xmemchk:
 * @void: 
 * 
 * Check for bounds overruns in all memory allocated with xmalloc(),
 * xrealloc(), and xstrdup().  Information on corrupted blocks is
 * rendered on the standard error stream.  This includes where the
 * block was allocated, the size of the block, and the number of
 * allocations made since the block was created.
 **/
void xmemchk(void)
{
        uint32_t    last_key;
        chk_header *ch;
        int         i;

	if (naddr > MAX_ADDRS) {
		fprintf(stderr, "ERROR: Too many addresses for xmemchk()!\n");
		abort();
	}

        last_key = 0;
	for (i = 0; i < naddr; i++) {
                /* Check for table corruption */
                if (mem_item[i].key  < last_key) {
                        fprintf(stderr, "Memory table keys out of order - fatal error");
                        abort();
                }
                last_key = mem_item[i].key;
                if (mem_item[i].addr == NULL) {
                        fprintf(stderr, "Memory table entry reference null block - fatal error");
                        abort();
                }
                if (mem_item[i].filen == NULL) {
                        fprintf(stderr, "Memory table filename missing - fatal error");
                        abort();
                }
                if ((size_t) strlen(mem_item[i].filen) != mem_item[i].length) {
                        fprintf(stderr, "Memory table filename length corrupted - fatal error");
                        abort();
                }
                
                /* Check memory */
                ch = mem_item[i].addr;
                if (chk_header_okay(ch) == FALSE) {
                        /* Chk header display which side has gone awry */
			fprintf(stderr, "Memory check failed!\n");
			fprintf(stderr, "addr: %p", mem_item[i].addr);
                        fprintf(stderr, "  size: %6d", ch->size);
                        fprintf(stderr, "  age: %6d", tick - mem_item[i].est);
                        fprintf(stderr, "  file: %s", mem_item[i].filen);
                        fprintf(stderr, "  line: %d", mem_item[i].line);
                        fprintf(stderr, "\n");
                        abort();
                }
        }
}

static int 
alloc_blk_cmp_origin(const void *vab1, const void *vab2)
{
        const alloc_blk *ab1, *ab2;
        int sc;
        
        ab1 = (const alloc_blk*)vab1;
        ab2 = (const alloc_blk*)vab2;

        if (ab1->filen == NULL || ab2->filen == NULL) {
                if (ab1->filen == NULL && ab2->filen == NULL) {
                        return 0;
                } else if (ab1->filen == NULL) {
                        return +1;
                } else /* (ab2->filen == NULL)*/ {
                        return -1;
                }
        }

        sc = strcmp(ab1->filen, ab2->filen);
        if (sc == 0) {
                if (ab1->line > ab2->line) {
                        return +1;
                } else if (ab1->line == ab2->line) {
                        return 0;
                } else /* (ab1->line < ab2->line) */{
                        return -1;
                }
        }

        return sc;
}

static int
alloc_blk_cmp_est(const void *vab1, const void *vab2)
{
        const alloc_blk *ab1, *ab2;

        ab1 = (const alloc_blk*)vab1;        
        ab2 = (const alloc_blk*)vab2;
        
        if (ab1->est > ab2->est) {
                return +1;
        } else if (ab1->est == ab2->est) {
                return 0;
        } else {
                return -1;
        }
}

/**
 * xmemdmp:
 * @void: 
 * 
 * Dumps the address, size, age, and point of allocation in code.
 *
 **/
void 
xmemdmp(void)
{
	int i;
        block_release_all();
	if (naddr > MAX_ADDRS) {
		printf("ERROR: Too many addresses for xmemdmp()!\n");
		abort();
	}

        qsort(mem_item, naddr, sizeof(mem_item[0]), alloc_blk_cmp_est);

        for (i=0; i<naddr; i++) {
                printf("%5d",i);                               fflush(stdout);
                printf("  addr: %p", mem_item[i].addr);        fflush(stdout);
                printf("  size: %5d", mem_item[i].addr->size); fflush(stdout);
                printf("  age: %6d", tick - mem_item[i].est);  fflush(stdout);
                printf("  file: %s", mem_item[i].filen);       fflush(stdout);
                printf(":%d", mem_item[i].line);               fflush(stdout);
                if (mem_item[i].blen != 0) { 
                        printf("  \tblen %d", mem_item[i].blen);   
                        fflush(stdout);
                }
                printf("\n");
        }
	printf("Program initialisation finished at age %6d\n", tick-init);
        qsort(mem_item, naddr, sizeof(mem_item[0]), mem_key_cmp);
}


/* Because block_alloc recycles blocks we need to know which code
 * fragment takes over responsibility for the memory.  */

/**
 * xclaim: