1 /*****************************************************************************
2 * vlc_block.h: Data blocks management functions
3 *****************************************************************************
4 * Copyright (C) 2003 the VideoLAN team
7 * Authors: Laurent Aimar <fenrir@via.ecp.fr>
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 *****************************************************************************/
25 #define _VLC_BLOCK_H 1
27 /****************************************************************************
29 ****************************************************************************
30 * - block_sys_t is opaque and thus block_t->p_sys is PRIVATE
31 * - i_flags may not always be set (ie could be 0, even for a key frame
32 * it depends where you receive the buffer (before/after a packetizer
33 * and the demux/packetizer implementations.
34 * - i_dts/i_pts could be 0, it means no pts
35 * - i_length: length in microseond of the packet, can be null except in the
36 * sout where it is mandatory.
37 * - i_rate 0 or a valid input rate, look at vlc_input.h
39 * - i_buffer number of valid data pointed by p_buffer
40 * you can freely decrease it but never increase it yourself
42 * - p_buffer: pointer over datas. You should never overwrite it, you can
43 * only incremment it to skip datas, in others cases use block_Realloc
44 * (don't duplicate yourself in a bigger buffer, block_Realloc is
45 * optimised for prehader/postdatas increase)
46 ****************************************************************************/
47 typedef struct block_sys_t block_sys_t
;
49 /** The content doesn't follow the last block, or is probably broken */
50 #define BLOCK_FLAG_DISCONTINUITY 0x0001
52 #define BLOCK_FLAG_TYPE_I 0x0002
53 /** Inter frame with backward reference only */
54 #define BLOCK_FLAG_TYPE_P 0x0004
55 /** Inter frame with backward and forward reference */
56 #define BLOCK_FLAG_TYPE_B 0x0008
57 /** For inter frame when you don't know the real type */
58 #define BLOCK_FLAG_TYPE_PB 0x0010
59 /** Warn that this block is a header one */
60 #define BLOCK_FLAG_HEADER 0x0020
61 /** This is the last block of the frame */
62 #define BLOCK_FLAG_END_OF_FRAME 0x0040
63 /** This is not a key frame for bitrate shaping */
64 #define BLOCK_FLAG_NO_KEYFRAME 0x0080
65 /** This block contains a clock reference */
66 #define BLOCK_FLAG_CLOCK 0x0200
67 /** This block is scrambled */
68 #define BLOCK_FLAG_SCRAMBLED 0x0400
69 /** This block has to be decoded but not be displayed */
70 #define BLOCK_FLAG_PREROLL 0x0800
71 /** This block is corrupted and/or there is data loss */
72 #define BLOCK_FLAG_CORRUPTED 0x1000
74 #define BLOCK_FLAG_PRIVATE_MASK 0xffff0000
75 #define BLOCK_FLAG_PRIVATE_SHIFT 16
77 typedef void (*block_free_t
) (block_t
*);
90 int i_samples
; /* Used for audio */
96 /* Rudimentary support for overloading block (de)allocation. */
97 block_free_t pf_release
;
100 /****************************************************************************
102 ****************************************************************************
103 * - block_Alloc : create a new block with the requested size ( >= 0 ), return
105 * - block_Release : release a block allocated with block_Alloc.
106 * - block_Realloc : realloc a block,
107 * i_pre: how many bytes to insert before body if > 0, else how many
108 * bytes of body to skip (the latter can be done without using
109 * block_Realloc i_buffer -= -i_pre, p_buffer += -i_pre as i_pre < 0)
110 * i_body (>= 0): the final size of the body (decreasing it can directly
111 * be done with i_buffer = i_body).
112 * with preheader and or body (increase
113 * and decrease are supported). Use it as it is optimised.
114 * - block_Duplicate : create a copy of a block.
115 ****************************************************************************/
116 VLC_EXPORT( void, block_Init
, ( block_t
*, void *, size_t ) );
117 VLC_EXPORT( block_t
*, block_Alloc
, ( size_t ) );
118 VLC_EXPORT( block_t
*, block_Realloc
, ( block_t
*, ssize_t i_pre
, size_t i_body
) );
120 #define block_New( dummy, size ) block_Alloc(size)
122 static inline block_t
*block_Duplicate( block_t
*p_block
)
124 block_t
*p_dup
= block_Alloc( p_block
->i_buffer
);
128 p_dup
->i_dts
= p_block
->i_dts
;
129 p_dup
->i_pts
= p_block
->i_pts
;
130 p_dup
->i_flags
= p_block
->i_flags
;
131 p_dup
->i_length
= p_block
->i_length
;
132 p_dup
->i_rate
= p_block
->i_rate
;
133 p_dup
->i_samples
= p_block
->i_samples
;
134 memcpy( p_dup
->p_buffer
, p_block
->p_buffer
, p_block
->i_buffer
);
138 static inline void block_Release( block_t
*p_block
)
140 p_block
->pf_release( p_block
);
143 VLC_EXPORT( block_t
*, block_mmap_Alloc
, (void *addr
, size_t length
) );
144 VLC_EXPORT( block_t
*, block_File
, (int fd
) );
146 /****************************************************************************
147 * Chains of blocks functions helper
148 ****************************************************************************
149 * - block_ChainAppend : append a block the the last block of a chain. Try to
150 * avoid using with a lot of data as it's really slow, prefer
151 * block_ChainLastAppend
152 * - block_ChainLastAppend : use a pointer over a pointer to the next blocks,
154 * - block_ChainRelease : release a chain of block
155 * - block_ChainExtract : extract data from a chain, return real bytes counts
156 * - block_ChainGather : gather a chain, free it and return a block.
157 ****************************************************************************/
158 static inline void block_ChainAppend( block_t
**pp_list
, block_t
*p_block
)
160 if( *pp_list
== NULL
)
166 block_t
*p
= *pp_list
;
168 while( p
->p_next
) p
= p
->p_next
;
173 static inline void block_ChainLastAppend( block_t
***ppp_last
, block_t
*p_block
)
175 block_t
*p_last
= p_block
;
177 **ppp_last
= p_block
;
179 while( p_last
->p_next
) p_last
= p_last
->p_next
;
180 *ppp_last
= &p_last
->p_next
;
183 static inline void block_ChainRelease( block_t
*p_block
)
187 block_t
*p_next
= p_block
->p_next
;
188 block_Release( p_block
);
193 static size_t block_ChainExtract( block_t
*p_list
, void *p_data
, size_t i_max
)
196 uint8_t *p
= (uint8_t*)p_data
;
198 while( p_list
&& i_max
)
200 size_t i_copy
= __MIN( i_max
, p_list
->i_buffer
);
201 memcpy( p
, p_list
->p_buffer
, i_copy
);
206 p_list
= p_list
->p_next
;
211 static inline block_t
*block_ChainGather( block_t
*p_list
)
214 mtime_t i_length
= 0;
217 if( p_list
->p_next
== NULL
)
218 return p_list
; /* Already gathered */
220 for( b
= p_list
; b
!= NULL
; b
= b
->p_next
)
222 i_total
+= b
->i_buffer
;
223 i_length
+= b
->i_length
;
226 g
= block_Alloc( i_total
);
227 block_ChainExtract( p_list
, g
->p_buffer
, g
->i_buffer
);
229 g
->i_flags
= p_list
->i_flags
;
230 g
->i_pts
= p_list
->i_pts
;
231 g
->i_dts
= p_list
->i_dts
;
232 g
->i_length
= i_length
;
235 block_ChainRelease( p_list
);
240 /****************************************************************************
242 ****************************************************************************
243 * - block_FifoNew : create and init a new fifo
244 * - block_FifoRelease : destroy a fifo and free all blocks in it.
245 * - block_FifoEmpty : free all blocks in a fifo
246 * - block_FifoPut : put a block
247 * - block_FifoGet : get a packet from the fifo (and wait if it is empty)
248 * - block_FifoShow : show the first packet of the fifo (and wait if
249 * needed), be carefull, you can use it ONLY if you are sure to be the
250 * only one getting data from the fifo.
251 * - block_FifoCount : how many packets are waiting in the fifo
252 * - block_FifoSize : how many cumulated bytes are waiting in the fifo
253 * - block_FifoWake : wake ups a thread with block_FifoGet() = NULL
254 * (this is used to wakeup a thread when there is no data to queue)
255 ****************************************************************************/
257 VLC_EXPORT( block_fifo_t
*, block_FifoNew
, ( void ) );
258 VLC_EXPORT( void, block_FifoRelease
, ( block_fifo_t
* ) );
259 VLC_EXPORT( void, block_FifoEmpty
, ( block_fifo_t
* ) );
260 VLC_EXPORT( size_t, block_FifoPut
, ( block_fifo_t
*, block_t
* ) );
261 VLC_EXPORT( void, block_FifoWake
, ( block_fifo_t
* ) );
262 VLC_EXPORT( block_t
*, block_FifoGet
, ( block_fifo_t
* ) );
263 VLC_EXPORT( block_t
*, block_FifoShow
, ( block_fifo_t
* ) );
264 VLC_EXPORT( size_t, block_FifoSize
, ( const block_fifo_t
*p_fifo
) );
265 VLC_EXPORT( size_t, block_FifoCount
, ( const block_fifo_t
*p_fifo
) );
267 #endif /* VLC_BLOCK_H */