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 *****************************************************************************/
24 #if !defined( __LIBVLC__ )
25 #error You are not libvlc or one of its plugins. You cannot include this file
29 #define _VLC_BLOCK_H 1
31 /****************************************************************************
33 ****************************************************************************
34 * - block_sys_t is opaque and thus block_t->p_sys is PRIVATE
35 * - i_flags may not always be set (ie could be 0, even for a key frame
36 * it depends where you receive the buffer (before/after a packetizer
37 * and the demux/packetizer implementations.
38 * - i_dts/i_pts could be 0, it means no pts
39 * - i_length: length in microseond of the packet, can be null except in the
40 * sout where it is mandatory.
41 * - i_rate 0 or a valid input rate, look at vlc_input.h
43 * - i_buffer number of valid data pointed by p_buffer
44 * you can freely decrease it but never increase it yourself
46 * - p_buffer: pointer over datas. You should never overwrite it, you can
47 * only incremment it to skip datas, in others cases use block_Realloc
48 * (don't duplicate yourself in a bigger buffer, block_Realloc is
49 * optimised for prehader/postdatas increase)
50 ****************************************************************************/
51 typedef struct block_sys_t block_sys_t
;
53 /** The content doesn't follow the last block, or is probably broken */
54 #define BLOCK_FLAG_DISCONTINUITY 0x0001
56 #define BLOCK_FLAG_TYPE_I 0x0002
57 /** Inter frame with backward reference only */
58 #define BLOCK_FLAG_TYPE_P 0x0004
59 /** Inter frame with backward and forward reference */
60 #define BLOCK_FLAG_TYPE_B 0x0008
61 /** For inter frame when you don't know the real type */
62 #define BLOCK_FLAG_TYPE_PB 0x0010
63 /** Warn that this block is a header one */
64 #define BLOCK_FLAG_HEADER 0x0020
65 /** This is the last block of the frame */
66 #define BLOCK_FLAG_END_OF_FRAME 0x0040
67 /** This is not a key frame for bitrate shaping */
68 #define BLOCK_FLAG_NO_KEYFRAME 0x0080
69 /** This block contains a clock reference */
70 #define BLOCK_FLAG_CLOCK 0x0200
71 /** This block is scrambled */
72 #define BLOCK_FLAG_SCRAMBLED 0x0400
73 /** This block has to be decoded but not be displayed */
74 #define BLOCK_FLAG_PREROLL 0x0800
75 /** This block is corrupted and/or there is data loss */
76 #define BLOCK_FLAG_CORRUPTED 0x1000
78 #define BLOCK_FLAG_PRIVATE_MASK 0xffff0000
79 #define BLOCK_FLAG_PRIVATE_SHIFT 16
81 typedef void (*block_free_t
) (block_t
*);
94 int i_samples
; /* Used for audio */
100 /* Rudimentary support for overloading block (de)allocation. */
101 block_free_t pf_release
;
104 /****************************************************************************
106 ****************************************************************************
107 * - block_New : create a new block with the requested size ( >= 0 ), return
109 * - block_Release : release a block allocated with block_New.
110 * - block_Realloc : realloc a block,
111 * i_pre: how many bytes to insert before body if > 0, else how many
112 * bytes of body to skip (the latter can be done without using
113 * block_Realloc i_buffer -= -i_pre, p_buffer += -i_pre as i_pre < 0)
114 * i_body (>= 0): the final size of the body (decreasing it can directly
115 * be done with i_buffer = i_body).
116 * with preheader and or body (increase
117 * and decrease are supported). Use it as it is optimised.
118 * - block_Duplicate : create a copy of a block.
119 ****************************************************************************/
120 VLC_EXPORT( void, block_Init
, ( block_t
*, void *, size_t ) );
121 VLC_EXPORT( block_t
*, block_Alloc
, ( size_t ) );
122 VLC_EXPORT( block_t
*, block_Realloc
, ( block_t
*, ssize_t i_pre
, size_t i_body
) );
124 static inline block_t
*block_New( void *dummy
, size_t size
)
127 return block_Alloc (size
);
130 static inline block_t
*block_Duplicate( block_t
*p_block
)
132 block_t
*p_dup
= block_New( NULL
, p_block
->i_buffer
);
136 p_dup
->i_dts
= p_block
->i_dts
;
137 p_dup
->i_pts
= p_block
->i_pts
;
138 p_dup
->i_flags
= p_block
->i_flags
;
139 p_dup
->i_length
= p_block
->i_length
;
140 p_dup
->i_rate
= p_block
->i_rate
;
141 p_dup
->i_samples
= p_block
->i_samples
;
142 memcpy( p_dup
->p_buffer
, p_block
->p_buffer
, p_block
->i_buffer
);
146 static inline void block_Release( block_t
*p_block
)
148 p_block
->pf_release( p_block
);
152 * Creates a block from a virtual address memory mapping (mmap).
153 * This is provided by LibVLC so that mmap blocks can safely be deallocated
154 * even after the allocating plugin has been unloaded from memory.
156 * @param addr base address of the mapping (as returned by mmap)
157 * @param length length (bytes) of the mapping (as passed to mmap)
158 * @return NULL if addr is MAP_FAILED, or an error occurred (in the later
159 * case, munmap(addr, length) is invoked before returning).
161 VLC_EXPORT( block_t
*, block_mmap_Alloc
, (void *addr
, size_t length
) );
163 /****************************************************************************
164 * Chains of blocks functions helper
165 ****************************************************************************
166 * - block_ChainAppend : append a block the the last block of a chain. Try to
167 * avoid using with a lot of data as it's really slow, prefer
168 * block_ChainLastAppend
169 * - block_ChainLastAppend : use a pointer over a pointer to the next blocks,
171 * - block_ChainRelease : release a chain of block
172 * - block_ChainExtract : extract data from a chain, return real bytes counts
173 * - block_ChainGather : gather a chain, free it and return a block.
174 ****************************************************************************/
175 static inline void block_ChainAppend( block_t
**pp_list
, block_t
*p_block
)
177 if( *pp_list
== NULL
)
183 block_t
*p
= *pp_list
;
185 while( p
->p_next
) p
= p
->p_next
;
190 static inline void block_ChainLastAppend( block_t
***ppp_last
, block_t
*p_block
)
192 block_t
*p_last
= p_block
;
194 **ppp_last
= p_block
;
196 while( p_last
->p_next
) p_last
= p_last
->p_next
;
197 *ppp_last
= &p_last
->p_next
;
200 static inline void block_ChainRelease( block_t
*p_block
)
204 block_t
*p_next
= p_block
->p_next
;
205 block_Release( p_block
);
210 static size_t block_ChainExtract( block_t
*p_list
, void *p_data
, size_t i_max
)
213 uint8_t *p
= (uint8_t*)p_data
;
215 while( p_list
&& i_max
)
217 size_t i_copy
= __MIN( i_max
, p_list
->i_buffer
);
218 memcpy( p
, p_list
->p_buffer
, i_copy
);
223 p_list
= p_list
->p_next
;
228 static inline block_t
*block_ChainGather( block_t
*p_list
)
231 mtime_t i_length
= 0;
234 if( p_list
->p_next
== NULL
)
235 return p_list
; /* Already gathered */
237 for( b
= p_list
; b
!= NULL
; b
= b
->p_next
)
239 i_total
+= b
->i_buffer
;
240 i_length
+= b
->i_length
;
243 g
= block_New( NULL
, i_total
);
244 block_ChainExtract( p_list
, g
->p_buffer
, g
->i_buffer
);
246 g
->i_flags
= p_list
->i_flags
;
247 g
->i_pts
= p_list
->i_pts
;
248 g
->i_dts
= p_list
->i_dts
;
249 g
->i_length
= i_length
;
252 block_ChainRelease( p_list
);
257 /****************************************************************************
259 ****************************************************************************
260 * - block_FifoNew : create and init a new fifo
261 * - block_FifoRelease : destroy a fifo and free all blocks in it.
262 * - block_FifoEmpty : free all blocks in a fifo
263 * - block_FifoPut : put a block
264 * - block_FifoGet : get a packet from the fifo (and wait if it is empty)
265 * - block_FifoShow : show the first packet of the fifo (and wait if
266 * needed), be carefull, you can use it ONLY if you are sure to be the
267 * only one getting data from the fifo.
268 * - block_FifoCount : how many packets are waiting in the fifo
269 * - block_FifoSize : how many cumulated bytes are waiting in the fifo
270 * - block_FifoWake : wake ups a thread with block_FifoGet() = NULL
271 * (this is used to wakeup a thread when there is no data to queue)
272 ****************************************************************************/
274 #define block_FifoNew( a ) __block_FifoNew( VLC_OBJECT(a) )
275 VLC_EXPORT( block_fifo_t
*, __block_FifoNew
, ( vlc_object_t
* ) );
276 VLC_EXPORT( void, block_FifoRelease
, ( block_fifo_t
* ) );
277 VLC_EXPORT( void, block_FifoEmpty
, ( block_fifo_t
* ) );
278 VLC_EXPORT( size_t, block_FifoPut
, ( block_fifo_t
*, block_t
* ) );
279 VLC_EXPORT( void, block_FifoWake
, ( block_fifo_t
* ) );
280 VLC_EXPORT( block_t
*, block_FifoGet
, ( block_fifo_t
* ) );
281 VLC_EXPORT( block_t
*, block_FifoShow
, ( block_fifo_t
* ) );
282 VLC_EXPORT( size_t, block_FifoSize
, ( const block_fifo_t
*p_fifo
) );
283 VLC_EXPORT( size_t, block_FifoCount
, ( const block_fifo_t
*p_fifo
) );
285 #endif /* VLC_BLOCK_H */