1 /*****************************************************************************
2 * block.c: Data blocks management functions
3 *****************************************************************************
4 * Copyright (C) 2003-2004 the VideoLAN team
7 * Authors: Laurent Aimar <fenrir@videolan.org>
9 * This program is free software; you can redistribute it and/or modify
10 * it under the terms of the GNU General Public License as published by
11 * the Free Software Foundation; either version 2 of the License, or
12 * (at your option) any later version.
14 * This program is distributed in the hope that it will be useful,
15 * but WITHOUT ANY WARRANTY; without even the implied warranty of
16 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
17 * GNU General Public License for more details.
19 * You should have received a copy of the GNU General Public License
20 * along with this program; if not, write to the Free Software
21 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston MA 02110-1301, USA.
22 *****************************************************************************/
24 /*****************************************************************************
26 *****************************************************************************/
30 #include "vlc_block.h"
32 /*****************************************************************************
34 *****************************************************************************/
38 uint8_t *p_allocated_buffer;
39 int i_allocated_buffer;
42 #define BLOCK_PADDING_SIZE 32
43 static void BlockRelease( block_t * );
45 block_t *__block_New( vlc_object_t *p_obj, int i_size )
47 /* We do only one malloc
48 * TODO bench if doing 2 malloc but keeping a pool of buffer is better
50 * 2 * BLOCK_PADDING_SIZE -> pre + post padding
53 const int i_alloc = i_size + 2 * BLOCK_PADDING_SIZE + 16;
55 malloc( sizeof( block_t ) + sizeof( block_sys_t ) + i_alloc );
57 if( p_block == NULL ) return NULL;
59 /* Fill opaque data */
60 p_sys = (block_sys_t*)( (uint8_t*)p_block + sizeof( block_t ) );
61 p_sys->i_allocated_buffer = i_alloc;
62 p_sys->p_allocated_buffer = (uint8_t*)p_block + sizeof( block_t ) +
63 sizeof( block_sys_t );
66 p_block->p_next = NULL;
67 p_block->p_prev = NULL;
71 p_block->i_length = 0;
73 p_block->i_buffer = i_size;
75 &p_sys->p_allocated_buffer[BLOCK_PADDING_SIZE +
76 16 - ((uintptr_t)p_sys->p_allocated_buffer % 16 )];
77 p_block->pf_release = BlockRelease;
79 /* Is ok, as no comunication between p_vlc */
80 p_block->p_manager = VLC_OBJECT( p_obj->p_libvlc );
81 p_block->p_sys = p_sys;
86 block_t *block_Realloc( block_t *p_block, int i_prebody, int i_body )
90 if( p_block->pf_release != BlockRelease )
92 /* Special case when pf_release if overloaded
93 * TODO if used one day, them implement it in a smarter way */
94 block_t *p_dup = block_Duplicate( p_block );
95 block_Release( p_block );
100 i_buffer_size = i_prebody + i_body;
102 if( i_body < 0 || i_buffer_size <= 0 ) return NULL;
104 if( p_block->p_buffer - i_prebody > p_block->p_sys->p_allocated_buffer &&
105 p_block->p_buffer - i_prebody < p_block->p_sys->p_allocated_buffer +
106 p_block->p_sys->i_allocated_buffer )
108 p_block->p_buffer -= i_prebody;
109 p_block->i_buffer += i_prebody;
112 if( p_block->p_buffer + i_body < p_block->p_sys->p_allocated_buffer +
113 p_block->p_sys->i_allocated_buffer )
115 p_block->i_buffer = i_buffer_size;
119 if( i_body > 0 || i_prebody > 0 )
121 block_t *p_rea = block_New( p_block->p_manager, i_buffer_size );
123 p_rea->i_dts = p_block->i_dts;
124 p_rea->i_pts = p_block->i_pts;
125 p_rea->i_flags = p_block->i_flags;
126 p_rea->i_length = p_block->i_length;
127 p_rea->i_rate = p_block->i_rate;
128 p_rea->i_samples = p_block->i_samples;
130 memcpy( p_rea->p_buffer + i_prebody, p_block->p_buffer,
131 __MIN( p_block->i_buffer, p_rea->i_buffer - i_prebody ) );
133 block_Release( p_block );
141 static void BlockRelease( block_t *p_block )
147 /*****************************************************************************
148 * block_fifo_t management
149 *****************************************************************************/
150 block_fifo_t *__block_FifoNew( vlc_object_t *p_obj )
152 block_fifo_t *p_fifo;
154 p_fifo = malloc( sizeof( block_fifo_t ) );
155 vlc_mutex_init( p_obj, &p_fifo->lock );
156 vlc_cond_init( p_obj, &p_fifo->wait );
157 p_fifo->i_depth = p_fifo->i_size = 0;
158 p_fifo->p_first = NULL;
159 p_fifo->pp_last = &p_fifo->p_first;
164 void block_FifoRelease( block_fifo_t *p_fifo )
166 block_FifoEmpty( p_fifo );
167 vlc_cond_destroy( &p_fifo->wait );
168 vlc_mutex_destroy( &p_fifo->lock );
172 void block_FifoEmpty( block_fifo_t *p_fifo )
176 vlc_mutex_lock( &p_fifo->lock );
177 for( b = p_fifo->p_first; b != NULL; )
186 p_fifo->i_depth = p_fifo->i_size = 0;
187 p_fifo->p_first = NULL;
188 p_fifo->pp_last = &p_fifo->p_first;
189 vlc_mutex_unlock( &p_fifo->lock );
192 int block_FifoPut( block_fifo_t *p_fifo, block_t *p_block )
195 vlc_mutex_lock( &p_fifo->lock );
199 i_size += p_block->i_buffer;
201 *p_fifo->pp_last = p_block;
202 p_fifo->pp_last = &p_block->p_next;
204 p_fifo->i_size += p_block->i_buffer;
206 p_block = p_block->p_next;
210 /* warn there is data in this fifo */
211 vlc_cond_signal( &p_fifo->wait );
212 vlc_mutex_unlock( &p_fifo->lock );
217 block_t *block_FifoGet( block_fifo_t *p_fifo )
221 vlc_mutex_lock( &p_fifo->lock );
223 /* We do a while here because there is a race condition in the
224 * win32 implementation of vlc_cond_wait() (We can't be sure the fifo
225 * hasn't been emptied again since we were signaled). */
226 while( p_fifo->p_first == NULL )
228 vlc_cond_wait( &p_fifo->wait, &p_fifo->lock );
233 p_fifo->p_first = b->p_next;
235 p_fifo->i_size -= b->i_buffer;
237 if( p_fifo->p_first == NULL )
239 p_fifo->pp_last = &p_fifo->p_first;
242 vlc_mutex_unlock( &p_fifo->lock );
248 block_t *block_FifoShow( block_fifo_t *p_fifo )
252 vlc_mutex_lock( &p_fifo->lock );
254 if( p_fifo->p_first == NULL )
256 vlc_cond_wait( &p_fifo->wait, &p_fifo->lock );
261 vlc_mutex_unlock( &p_fifo->lock );