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			508 lines
		
	
	
	
		
			11 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			508 lines
		
	
	
	
		
			11 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
| /*
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|  * default memory allocator for libavutil
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|  * Copyright (c) 2002 Fabrice Bellard
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|  *
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|  * This file is part of FFmpeg.
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|  *
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|  * FFmpeg is free software; you can redistribute it and/or
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|  * modify it under the terms of the GNU Lesser General Public
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|  * License as published by the Free Software Foundation; either
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|  * version 2.1 of the License, or (at your option) any later version.
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|  *
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|  * FFmpeg is distributed in the hope that it will be useful,
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|  * but WITHOUT ANY WARRANTY; without even the implied warranty of
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|  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
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|  * Lesser General Public License for more details.
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|  *
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|  * You should have received a copy of the GNU Lesser General Public
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|  * License along with FFmpeg; if not, write to the Free Software
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|  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
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|  */
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| 
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| /**
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|  * @file
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|  * default memory allocator for libavutil
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|  */
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| 
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| #define _XOPEN_SOURCE 600
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| 
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| #include "config.h"
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| 
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| #include <limits.h>
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| #include <stdint.h>
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| #include <stdlib.h>
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| #include <string.h>
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| #if HAVE_MALLOC_H
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| #include <malloc.h>
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| #endif
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| 
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| #include "avassert.h"
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| #include "avutil.h"
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| #include "common.h"
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| #include "dynarray.h"
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| #include "intreadwrite.h"
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| #include "mem.h"
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| 
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| #ifdef MALLOC_PREFIX
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| 
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| #define malloc         AV_JOIN(MALLOC_PREFIX, malloc)
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| #define memalign       AV_JOIN(MALLOC_PREFIX, memalign)
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| #define posix_memalign AV_JOIN(MALLOC_PREFIX, posix_memalign)
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| #define realloc        AV_JOIN(MALLOC_PREFIX, realloc)
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| #define free           AV_JOIN(MALLOC_PREFIX, free)
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| 
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| void *malloc(size_t size);
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| void *memalign(size_t align, size_t size);
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| int   posix_memalign(void **ptr, size_t align, size_t size);
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| void *realloc(void *ptr, size_t size);
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| void  free(void *ptr);
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| 
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| #endif /* MALLOC_PREFIX */
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| 
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| #include "mem_internal.h"
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| 
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| #define ALIGN (HAVE_AVX512 ? 64 : (HAVE_AVX ? 32 : 16))
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| 
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| /* NOTE: if you want to override these functions with your own
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|  * implementations (not recommended) you have to link libav* as
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|  * dynamic libraries and remove -Wl,-Bsymbolic from the linker flags.
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|  * Note that this will cost performance. */
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| 
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| static size_t max_alloc_size= INT_MAX;
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| 
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| void av_max_alloc(size_t max){
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|     max_alloc_size = max;
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| }
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| 
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| void *av_malloc(size_t size)
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| {
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|     void *ptr = NULL;
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| 
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|     /* let's disallow possibly ambiguous cases */
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|     if (size > (max_alloc_size - 32))
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|         return NULL;
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| 
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| #if HAVE_POSIX_MEMALIGN
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|     if (size) //OS X on SDK 10.6 has a broken posix_memalign implementation
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|     if (posix_memalign(&ptr, ALIGN, size))
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|         ptr = NULL;
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| #elif HAVE_ALIGNED_MALLOC
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|     ptr = _aligned_malloc(size, ALIGN);
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| #elif HAVE_MEMALIGN
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| #ifndef __DJGPP__
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|     ptr = memalign(ALIGN, size);
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| #else
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|     ptr = memalign(size, ALIGN);
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| #endif
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|     /* Why 64?
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|      * Indeed, we should align it:
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|      *   on  4 for 386
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|      *   on 16 for 486
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|      *   on 32 for 586, PPro - K6-III
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|      *   on 64 for K7 (maybe for P3 too).
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|      * Because L1 and L2 caches are aligned on those values.
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|      * But I don't want to code such logic here!
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|      */
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|     /* Why 32?
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|      * For AVX ASM. SSE / NEON needs only 16.
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|      * Why not larger? Because I did not see a difference in benchmarks ...
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|      */
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|     /* benchmarks with P3
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|      * memalign(64) + 1          3071, 3051, 3032
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|      * memalign(64) + 2          3051, 3032, 3041
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|      * memalign(64) + 4          2911, 2896, 2915
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|      * memalign(64) + 8          2545, 2554, 2550
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|      * memalign(64) + 16         2543, 2572, 2563
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|      * memalign(64) + 32         2546, 2545, 2571
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|      * memalign(64) + 64         2570, 2533, 2558
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|      *
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|      * BTW, malloc seems to do 8-byte alignment by default here.
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|      */
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| #else
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|     ptr = malloc(size);
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| #endif
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|     if(!ptr && !size) {
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|         size = 1;
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|         ptr= av_malloc(1);
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|     }
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| #if CONFIG_MEMORY_POISONING
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|     if (ptr)
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|         memset(ptr, FF_MEMORY_POISON, size);
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| #endif
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|     return ptr;
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| }
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| 
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| void *av_realloc(void *ptr, size_t size)
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| {
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|     /* let's disallow possibly ambiguous cases */
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|     if (size > (max_alloc_size - 32))
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|         return NULL;
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| 
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| #if HAVE_ALIGNED_MALLOC
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|     return _aligned_realloc(ptr, size + !size, ALIGN);
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| #else
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|     return realloc(ptr, size + !size);
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| #endif
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| }
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| 
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| void *av_realloc_f(void *ptr, size_t nelem, size_t elsize)
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| {
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|     size_t size;
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|     void *r;
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| 
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|     if (av_size_mult(elsize, nelem, &size)) {
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|         av_free(ptr);
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|         return NULL;
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|     }
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|     r = av_realloc(ptr, size);
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|     if (!r)
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|         av_free(ptr);
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|     return r;
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| }
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| 
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| int av_reallocp(void *ptr, size_t size)
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| {
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|     void *val;
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| 
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|     if (!size) {
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|         av_freep(ptr);
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|         return 0;
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|     }
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| 
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|     memcpy(&val, ptr, sizeof(val));
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|     val = av_realloc(val, size);
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| 
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|     if (!val) {
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|         av_freep(ptr);
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|         return AVERROR(ENOMEM);
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|     }
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| 
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|     memcpy(ptr, &val, sizeof(val));
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|     return 0;
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| }
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| 
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| void *av_malloc_array(size_t nmemb, size_t size)
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| {
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|     if (!size || nmemb >= INT_MAX / size)
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|         return NULL;
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|     return av_malloc(nmemb * size);
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| }
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| 
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| void *av_mallocz_array(size_t nmemb, size_t size)
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| {
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|     if (!size || nmemb >= INT_MAX / size)
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|         return NULL;
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|     return av_mallocz(nmemb * size);
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| }
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| 
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| void *av_realloc_array(void *ptr, size_t nmemb, size_t size)
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| {
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|     if (!size || nmemb >= INT_MAX / size)
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|         return NULL;
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|     return av_realloc(ptr, nmemb * size);
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| }
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| 
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| int av_reallocp_array(void *ptr, size_t nmemb, size_t size)
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| {
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|     void *val;
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| 
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|     memcpy(&val, ptr, sizeof(val));
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|     val = av_realloc_f(val, nmemb, size);
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|     memcpy(ptr, &val, sizeof(val));
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|     if (!val && nmemb && size)
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|         return AVERROR(ENOMEM);
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| 
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|     return 0;
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| }
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| 
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| void av_free(void *ptr)
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| {
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| #if HAVE_ALIGNED_MALLOC
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|     _aligned_free(ptr);
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| #else
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|     free(ptr);
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| #endif
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| }
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| 
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| void av_freep(void *arg)
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| {
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|     void *val;
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| 
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|     memcpy(&val, arg, sizeof(val));
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|     memcpy(arg, &(void *){ NULL }, sizeof(val));
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|     av_free(val);
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| }
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| 
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| void *av_mallocz(size_t size)
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| {
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|     void *ptr = av_malloc(size);
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|     if (ptr)
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|         memset(ptr, 0, size);
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|     return ptr;
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| }
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| 
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| void *av_calloc(size_t nmemb, size_t size)
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| {
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|     if (size <= 0 || nmemb >= INT_MAX / size)
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|         return NULL;
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|     return av_mallocz(nmemb * size);
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| }
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| 
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| char *av_strdup(const char *s)
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| {
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|     char *ptr = NULL;
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|     if (s) {
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|         size_t len = strlen(s) + 1;
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|         ptr = av_realloc(NULL, len);
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|         if (ptr)
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|             memcpy(ptr, s, len);
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|     }
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|     return ptr;
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| }
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| 
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| char *av_strndup(const char *s, size_t len)
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| {
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|     char *ret = NULL, *end;
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| 
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|     if (!s)
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|         return NULL;
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| 
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|     end = memchr(s, 0, len);
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|     if (end)
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|         len = end - s;
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| 
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|     ret = av_realloc(NULL, len + 1);
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|     if (!ret)
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|         return NULL;
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| 
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|     memcpy(ret, s, len);
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|     ret[len] = 0;
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|     return ret;
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| }
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| 
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| void *av_memdup(const void *p, size_t size)
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| {
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|     void *ptr = NULL;
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|     if (p) {
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|         ptr = av_malloc(size);
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|         if (ptr)
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|             memcpy(ptr, p, size);
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|     }
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|     return ptr;
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| }
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| 
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| int av_dynarray_add_nofree(void *tab_ptr, int *nb_ptr, void *elem)
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| {
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|     void **tab;
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|     memcpy(&tab, tab_ptr, sizeof(tab));
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| 
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|     FF_DYNARRAY_ADD(INT_MAX, sizeof(*tab), tab, *nb_ptr, {
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|         tab[*nb_ptr] = elem;
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|         memcpy(tab_ptr, &tab, sizeof(tab));
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|     }, {
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|         return AVERROR(ENOMEM);
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|     });
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|     return 0;
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| }
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| 
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| void av_dynarray_add(void *tab_ptr, int *nb_ptr, void *elem)
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| {
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|     void **tab;
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|     memcpy(&tab, tab_ptr, sizeof(tab));
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| 
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|     FF_DYNARRAY_ADD(INT_MAX, sizeof(*tab), tab, *nb_ptr, {
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|         tab[*nb_ptr] = elem;
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|         memcpy(tab_ptr, &tab, sizeof(tab));
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|     }, {
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|         *nb_ptr = 0;
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|         av_freep(tab_ptr);
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|     });
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| }
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| 
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| void *av_dynarray2_add(void **tab_ptr, int *nb_ptr, size_t elem_size,
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|                        const uint8_t *elem_data)
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| {
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|     uint8_t *tab_elem_data = NULL;
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| 
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|     FF_DYNARRAY_ADD(INT_MAX, elem_size, *tab_ptr, *nb_ptr, {
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|         tab_elem_data = (uint8_t *)*tab_ptr + (*nb_ptr) * elem_size;
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|         if (elem_data)
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|             memcpy(tab_elem_data, elem_data, elem_size);
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|         else if (CONFIG_MEMORY_POISONING)
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|             memset(tab_elem_data, FF_MEMORY_POISON, elem_size);
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|     }, {
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|         av_freep(tab_ptr);
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|         *nb_ptr = 0;
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|     });
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|     return tab_elem_data;
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| }
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| 
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| static void fill16(uint8_t *dst, int len)
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| {
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|     uint32_t v = AV_RN16(dst - 2);
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| 
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|     v |= v << 16;
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| 
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|     while (len >= 4) {
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|         AV_WN32(dst, v);
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|         dst += 4;
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|         len -= 4;
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|     }
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| 
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|     while (len--) {
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|         *dst = dst[-2];
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|         dst++;
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|     }
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| }
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| 
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| static void fill24(uint8_t *dst, int len)
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| {
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| #if HAVE_BIGENDIAN
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|     uint32_t v = AV_RB24(dst - 3);
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|     uint32_t a = v << 8  | v >> 16;
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|     uint32_t b = v << 16 | v >> 8;
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|     uint32_t c = v << 24 | v;
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| #else
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|     uint32_t v = AV_RL24(dst - 3);
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|     uint32_t a = v       | v << 24;
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|     uint32_t b = v >> 8  | v << 16;
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|     uint32_t c = v >> 16 | v << 8;
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| #endif
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| 
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|     while (len >= 12) {
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|         AV_WN32(dst,     a);
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|         AV_WN32(dst + 4, b);
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|         AV_WN32(dst + 8, c);
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|         dst += 12;
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|         len -= 12;
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|     }
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| 
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|     if (len >= 4) {
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|         AV_WN32(dst, a);
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|         dst += 4;
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|         len -= 4;
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|     }
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| 
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|     if (len >= 4) {
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|         AV_WN32(dst, b);
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|         dst += 4;
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|         len -= 4;
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|     }
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| 
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|     while (len--) {
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|         *dst = dst[-3];
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|         dst++;
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|     }
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| }
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| 
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| static void fill32(uint8_t *dst, int len)
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| {
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|     uint32_t v = AV_RN32(dst - 4);
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| 
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| #if HAVE_FAST_64BIT
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|     uint64_t v2= v + ((uint64_t)v<<32);
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|     while (len >= 32) {
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|         AV_WN64(dst   , v2);
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|         AV_WN64(dst+ 8, v2);
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|         AV_WN64(dst+16, v2);
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|         AV_WN64(dst+24, v2);
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|         dst += 32;
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|         len -= 32;
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|     }
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| #endif
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| 
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|     while (len >= 4) {
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|         AV_WN32(dst, v);
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|         dst += 4;
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|         len -= 4;
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|     }
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| 
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|     while (len--) {
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|         *dst = dst[-4];
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|         dst++;
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|     }
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| }
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| 
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| void av_memcpy_backptr(uint8_t *dst, int back, int cnt)
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| {
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|     const uint8_t *src = &dst[-back];
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|     if (!back)
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|         return;
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| 
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|     if (back == 1) {
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|         memset(dst, *src, cnt);
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|     } else if (back == 2) {
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|         fill16(dst, cnt);
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|     } else if (back == 3) {
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|         fill24(dst, cnt);
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|     } else if (back == 4) {
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|         fill32(dst, cnt);
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|     } else {
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|         if (cnt >= 16) {
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|             int blocklen = back;
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|             while (cnt > blocklen) {
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|                 memcpy(dst, src, blocklen);
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|                 dst       += blocklen;
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|                 cnt       -= blocklen;
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|                 blocklen <<= 1;
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|             }
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|             memcpy(dst, src, cnt);
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|             return;
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|         }
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|         if (cnt >= 8) {
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|             AV_COPY32U(dst,     src);
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|             AV_COPY32U(dst + 4, src + 4);
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|             src += 8;
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|             dst += 8;
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|             cnt -= 8;
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|         }
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|         if (cnt >= 4) {
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|             AV_COPY32U(dst, src);
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|             src += 4;
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|             dst += 4;
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|             cnt -= 4;
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|         }
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|         if (cnt >= 2) {
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|             AV_COPY16U(dst, src);
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|             src += 2;
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|             dst += 2;
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|             cnt -= 2;
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|         }
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|         if (cnt)
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|             *dst = *src;
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|     }
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| }
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| 
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| void *av_fast_realloc(void *ptr, unsigned int *size, size_t min_size)
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| {
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|     if (min_size <= *size)
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|         return ptr;
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| 
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|     if (min_size > max_alloc_size - 32) {
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|         *size = 0;
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|         return NULL;
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|     }
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| 
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|     min_size = FFMIN(max_alloc_size - 32, FFMAX(min_size + min_size / 16 + 32, min_size));
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| 
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|     ptr = av_realloc(ptr, min_size);
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|     /* we could set this to the unmodified min_size but this is safer
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|      * if the user lost the ptr and uses NULL now
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|      */
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|     if (!ptr)
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|         min_size = 0;
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| 
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|     *size = min_size;
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| 
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|     return ptr;
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| }
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| 
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| void av_fast_malloc(void *ptr, unsigned int *size, size_t min_size)
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| {
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|     ff_fast_malloc(ptr, size, min_size, 0);
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| }
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| 
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| void av_fast_mallocz(void *ptr, unsigned int *size, size_t min_size)
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| {
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|     ff_fast_malloc(ptr, size, min_size, 1);
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| }
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