1 /*****************************************************************************
2 * block.c: Data blocks management functions
3 *****************************************************************************
4 * Copyright (C) 2003-2004 VideoLAN
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., 59 Temple Place - Suite 330, Boston, MA 02111, 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;
70 p_block->i_length = 0;
72 p_block->i_buffer = i_size;
74 &p_sys->p_allocated_buffer[BLOCK_PADDING_SIZE +
75 16 - ((uintptr_t)p_sys->p_allocated_buffer % 16 )];
76 p_block->pf_release = BlockRelease;
78 /* Is ok, as no comunication between p_vlc */
79 p_block->p_manager = VLC_OBJECT( p_obj->p_vlc );
80 p_block->p_sys = p_sys;
85 block_t *block_Realloc( block_t *p_block, int i_prebody, int i_body )
89 if( p_block->pf_release != BlockRelease )
91 /* Special case when pf_release if overloaded
92 * TODO if used one day, them implement it in a smarter way */
93 block_t *p_dup = block_Duplicate( p_block );
94 block_Release( p_block );
99 i_buffer_size = i_prebody + i_body;
101 if( i_body < 0 || i_buffer_size <= 0 ) return NULL;
103 if( i_prebody < ( p_block->p_buffer - p_block->p_sys->p_allocated_buffer +
104 p_block->p_sys->i_allocated_buffer ) ||
105 p_block->p_buffer - i_prebody > p_block->p_sys->p_allocated_buffer )
107 p_block->p_buffer -= i_prebody;
108 p_block->i_buffer += i_prebody;
111 if( p_block->p_buffer + i_body < p_block->p_sys->p_allocated_buffer +
112 p_block->p_sys->i_allocated_buffer )
114 p_block->i_buffer = i_buffer_size;
118 if( i_body > 0 || i_prebody > 0 )
120 block_t *p_rea = block_New( p_block->p_manager, i_buffer_size );
122 p_rea->i_dts = p_block->i_dts;
123 p_rea->i_pts = p_block->i_pts;
124 p_rea->i_flags = p_block->i_flags;
125 p_rea->i_length= p_block->i_length;
126 p_rea->i_rate = p_block->i_rate;
128 memcpy( p_rea->p_buffer + i_prebody, p_block->p_buffer,
129 __MIN( p_block->i_buffer, p_rea->i_buffer - i_prebody ) );
131 block_Release( p_block );
139 static void BlockRelease( block_t *p_block )
145 /*****************************************************************************
146 * block_fifo_t management
147 *****************************************************************************/
148 block_fifo_t *__block_FifoNew( vlc_object_t *p_obj )
150 block_fifo_t *p_fifo;
152 p_fifo = malloc( sizeof( vlc_object_t ) );
153 vlc_mutex_init( p_obj, &p_fifo->lock );
154 vlc_cond_init( p_obj, &p_fifo->wait );
155 p_fifo->i_depth = p_fifo->i_size = 0;
156 p_fifo->p_first = NULL;
157 p_fifo->pp_last = &p_fifo->p_first;
162 void block_FifoRelease( block_fifo_t *p_fifo )
164 block_FifoEmpty( p_fifo );
165 vlc_cond_destroy( &p_fifo->wait );
166 vlc_mutex_destroy( &p_fifo->lock );
170 void block_FifoEmpty( block_fifo_t *p_fifo )
174 vlc_mutex_lock( &p_fifo->lock );
175 for( b = p_fifo->p_first; b != NULL; )
184 p_fifo->i_depth = p_fifo->i_size = 0;
185 p_fifo->p_first = NULL;
186 p_fifo->pp_last = &p_fifo->p_first;
187 vlc_mutex_unlock( &p_fifo->lock );
190 int block_FifoPut( block_fifo_t *p_fifo, block_t *p_block )
193 vlc_mutex_lock( &p_fifo->lock );
197 i_size += p_block->i_buffer;
199 *p_fifo->pp_last = p_block;
200 p_fifo->pp_last = &p_block->p_next;
202 p_fifo->i_size += p_block->i_buffer;
204 p_block = p_block->p_next;
208 /* warn there is data in this fifo */
209 vlc_cond_signal( &p_fifo->wait );
210 vlc_mutex_unlock( &p_fifo->lock );
215 block_t *block_FifoGet( block_fifo_t *p_fifo )
219 vlc_mutex_lock( &p_fifo->lock );
221 /* We do a while here because there is a race condition in the
222 * win32 implementation of vlc_cond_wait() (We can't be sure the fifo
223 * hasn't been emptied again since we were signaled). */
224 while( p_fifo->p_first == NULL )
226 vlc_cond_wait( &p_fifo->wait, &p_fifo->lock );
231 p_fifo->p_first = b->p_next;
233 p_fifo->i_size -= b->i_buffer;
235 if( p_fifo->p_first == NULL )
237 p_fifo->pp_last = &p_fifo->p_first;
240 vlc_mutex_unlock( &p_fifo->lock );
246 block_t *block_FifoShow( block_fifo_t *p_fifo )
250 vlc_mutex_lock( &p_fifo->lock );
252 if( p_fifo->p_first == NULL )
254 vlc_cond_wait( &p_fifo->wait, &p_fifo->lock );
259 vlc_mutex_unlock( &p_fifo->lock );