common/multibuf.c

   1 /*****************************************************************************
   2  * multibuf.c
   3  *****************************************************************************
   4  * Copyright (C) 2011-2015 L-SMASH project
   5  *
   6  * Authors: Yusuke Nakamura <muken.the.vfrmaniac@gmail.com>
   7  *
   8  * Permission to use, copy, modify, and/or distribute this software for any
   9  * purpose with or without fee is hereby granted, provided that the above
  10  * copyright notice and this permission notice appear in all copies.
  11  *
  12  * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
  13  * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
  14  * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
  15  * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
  16  * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
  17  * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
  18  * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
  19  *****************************************************************************/
  20
  21 /* This file is available under an ISC license. */
  22
  23 #include "internal.h" /* must be placed first */
  24
  25 #include <string.h>
  26
  27 lsmash_multiple_buffers_t *lsmash_create_multiple_buffers( uint32_t number_of_buffers, uint32_t buffer_size )
  28 {
  29     if( (uint64_t)number_of_buffers * buffer_size > UINT32_MAX )
  30         return NULL;
  31     lsmash_multiple_buffers_t *multiple_buffer = lsmash_malloc( sizeof(lsmash_multiple_buffers_t) );
  32     if( !multiple_buffer )
  33         return NULL;
  34     multiple_buffer->buffers = lsmash_malloc( number_of_buffers * buffer_size );
  35     if( !multiple_buffer->buffers )
  36     {
  37         lsmash_free( multiple_buffer );
  38         return NULL;
  39     }
  40     multiple_buffer->number_of_buffers = number_of_buffers;
  41     multiple_buffer->buffer_size = buffer_size;
  42     return multiple_buffer;
  43 }
  44
  45 void *lsmash_withdraw_buffer( lsmash_multiple_buffers_t *multiple_buffer, uint32_t buffer_number )
  46 {
  47     if( !multiple_buffer || !buffer_number || buffer_number > multiple_buffer->number_of_buffers )
  48         return NULL;
  49     return (uint8_t *)multiple_buffer->buffers + (buffer_number - 1) * multiple_buffer->buffer_size;
  50 }
  51
  52 lsmash_multiple_buffers_t *lsmash_resize_multiple_buffers( lsmash_multiple_buffers_t *multiple_buffer, uint32_t buffer_size )
  53 {
  54     if( !multiple_buffer )
  55         return NULL;
  56     if( buffer_size == multiple_buffer->buffer_size )
  57         return multiple_buffer;
  58     if( (uint64_t)multiple_buffer->number_of_buffers * buffer_size > UINT32_MAX )
  59         return NULL;
  60     uint8_t *temp;
  61     if( buffer_size > multiple_buffer->buffer_size )
  62     {
  63         temp = lsmash_realloc( multiple_buffer->buffers, multiple_buffer->number_of_buffers * buffer_size );
  64         if( !temp )
  65             return NULL;
  66         for( uint32_t i = multiple_buffer->number_of_buffers - 1; i ; i-- )
  67             memmove( temp + buffer_size, temp + i * multiple_buffer->buffer_size, multiple_buffer->buffer_size );
  68     }
  69     else
  70     {
  71         for( uint32_t i = 1; i < multiple_buffer->number_of_buffers; i++ )
  72             memmove( (uint8_t *)multiple_buffer->buffers + buffer_size,
  73                      (uint8_t *)multiple_buffer->buffers + i * multiple_buffer->buffer_size,
  74                                 multiple_buffer->buffer_size );
  75         temp = lsmash_realloc( multiple_buffer->buffers, multiple_buffer->number_of_buffers * buffer_size );
  76         if( !temp )
  77             return NULL;
  78     }
  79     multiple_buffer->buffers     = temp;
  80     multiple_buffer->buffer_size = buffer_size;
  81     return multiple_buffer;
  82 }
  83
  84 void lsmash_destroy_multiple_buffers( lsmash_multiple_buffers_t *multiple_buffer )
  85 {
  86     if( !multiple_buffer )
  87         return;
  88     lsmash_free( multiple_buffer->buffers );
  89     lsmash_free( multiple_buffer );
  90 }