/***************************************************************************** * vlc_block.h: Data blocks management functions ***************************************************************************** * Copyright (C) 2003 the VideoLAN team * $Id: 581132a804f62692699241b244f014638e0dfded $ * * Authors: Laurent Aimar <fenrir@via.ecp.fr> * * This program is free software; you can redistribute it and/or modify * it under the terms of the GNU General Public License as published by * the Free Software Foundation; either version 2 of the License, or * (at your option) any later version. * * This program is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the * GNU General Public License for more details. * * You should have received a copy of the GNU General Public License * along with this program; if not, write to the Free Software * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston MA 02110-1301, USA. *****************************************************************************/#ifndef VLC_BLOCK_H#define VLC_BLOCK_H 1/** * \file * This file implements functions and structures to handle blocks of data in vlc * *//**************************************************************************** * block: **************************************************************************** * - block_sys_t is opaque and thus block_t->p_sys is PRIVATE * - i_flags may not always be set (ie could be 0, even for a key frame *      it depends where you receive the buffer (before/after a packetizer *      and the demux/packetizer implementations. * - i_dts/i_pts could be 0, it means no pts * - i_length: length in microseond of the packet, can be null except in the *      sout where it is mandatory. * - i_rate 0 or a valid input rate, look at vlc_input.h * * - i_buffer number of valid data pointed by p_buffer *      you can freely decrease it but never increase it yourself *      (use block_Realloc) * - p_buffer: pointer over datas. You should never overwrite it, you can *   only incremment it to skip datas, in others cases use block_Realloc *   (don't duplicate yourself in a bigger buffer, block_Realloc is *   optimised for prehader/postdatas increase) ****************************************************************************/typedef struct block_sys_t block_sys_t;/** The content doesn't follow the last block, or is probably broken */#define BLOCK_FLAG_DISCONTINUITY 0x0001/** Intra frame */#define BLOCK_FLAG_TYPE_I        0x0002/** Inter frame with backward reference only */#define BLOCK_FLAG_TYPE_P        0x0004/** Inter frame with backward and forward reference */#define BLOCK_FLAG_TYPE_B        0x0008/** For inter frame when you don't know the real type */#define BLOCK_FLAG_TYPE_PB       0x0010/** Warn that this block is a header one */#define BLOCK_FLAG_HEADER        0x0020/** This is the last block of the frame */#define BLOCK_FLAG_END_OF_FRAME  0x0040/** This is not a key frame for bitrate shaping */#define BLOCK_FLAG_NO_KEYFRAME   0x0080/** This block contains the last part of a sequence  */#define BLOCK_FLAG_END_OF_SEQUENCE 0x0100/** This block contains a clock reference */#define BLOCK_FLAG_CLOCK         0x0200/** This block is scrambled */#define BLOCK_FLAG_SCRAMBLED     0x0400/** This block has to be decoded but not be displayed */#define BLOCK_FLAG_PREROLL       0x0800/** This block is corrupted and/or there is data loss  */#define BLOCK_FLAG_CORRUPTED     0x1000#define BLOCK_FLAG_TYPE_MASK \    (BLOCK_FLAG_TYPE_I|BLOCK_FLAG_TYPE_P|BLOCK_FLAG_TYPE_B|BLOCK_FLAG_TYPE_PB)/* These are for input core private usage only */#define BLOCK_FLAG_CORE_PRIVATE_MASK  0x00ff0000#define BLOCK_FLAG_CORE_PRIVATE_SHIFT 16/* These are for module private usage only */#define BLOCK_FLAG_PRIVATE_MASK  0xff000000#define BLOCK_FLAG_PRIVATE_SHIFT 24typedef void (*block_free_t) (block_t *);struct block_t{    block_t     *p_next;    block_t     *p_prev;    uint32_t    i_flags;    mtime_t     i_pts;    mtime_t     i_dts;    mtime_t     i_length;    int         i_samples; /* Used for audio */    int         i_rate;    size_t      i_buffer;    uint8_t     *p_buffer;    /* Rudimentary support for overloading block (de)allocation. */    block_free_t pf_release;};/**************************************************************************** * Blocks functions: **************************************************************************** * - block_Alloc : create a new block with the requested size ( >= 0 ), return *      NULL for failure. * - block_Release : release a block allocated with block_Alloc. * - block_Realloc : realloc a block, *      i_pre: how many bytes to insert before body if > 0, else how many *      bytes of body to skip (the latter can be done without using *      block_Realloc i_buffer -= -i_pre, p_buffer += -i_pre as i_pre < 0) *      i_body (>= 0): the final size of the body (decreasing it can directly *      be done with i_buffer = i_body). *      with preheader and or body (increase *      and decrease are supported). Use it as it is optimised. * - block_Duplicate : create a copy of a block. ****************************************************************************/VLC_EXPORT( void,      block_Init,    ( block_t *, void *, size_t ) );VLC_EXPORT( block_t *, block_Alloc,   ( size_t ) LIBVLC_USED );VLC_EXPORT( block_t *, block_Realloc, ( block_t *, ssize_t i_pre, size_t i_body ) LIBVLC_USED );#define block_New( dummy, size ) block_Alloc(size)LIBVLC_USEDstatic inline block_t *block_Duplicate( block_t *p_block ){    block_t *p_dup = block_Alloc( p_block->i_buffer );    if( p_dup == NULL )        return NULL;    p_dup->i_dts     = p_block->i_dts;    p_dup->i_pts     = p_block->i_pts;    p_dup->i_flags   = p_block->i_flags;    p_dup->i_length  = p_block->i_length;    p_dup->i_rate    = p_block->i_rate;    p_dup->i_samples = p_block->i_samples;    memcpy( p_dup->p_buffer, p_block->p_buffer, p_block->i_buffer );    return p_dup;}static inline void block_Release( block_t *p_block ){    p_block->pf_release( p_block );}VLC_EXPORT( block_t *, block_mmap_Alloc, (void *addr, size_t length) LIBVLC_USED );VLC_EXPORT( block_t *, block_File, (int fd) LIBVLC_USED );static inline void block_Cleanup (void *block){    block_Release ((block_t *)block);}#define block_cleanup_push( block ) vlc_cleanup_push (block_Cleanup, block)/**************************************************************************** * Chains of blocks functions helper **************************************************************************** * - block_ChainAppend : append a block to the last block of a chain. Try to *      avoid using with a lot of data as it's really slow, prefer *      block_ChainLastAppend * - block_ChainLastAppend : use a pointer over a pointer to the next blocks, *      and update it. * - block_ChainRelease : release a chain of block * - block_ChainExtract : extract data from a chain, return real bytes counts * - block_ChainGather : gather a chain, free it and return one block. ****************************************************************************/static inline void block_ChainAppend( block_t **pp_list, block_t *p_block ){    if( *pp_list == NULL )    {        *pp_list = p_block;    }    else    {        block_t *p = *pp_list;        while( p->p_next ) p = p->p_next;        p->p_next = p_block;    }}static inline void block_ChainLastAppend( block_t ***ppp_last, block_t *p_block ){    block_t *p_last = p_block;    **ppp_last = p_block;    while( p_last->p_next ) p_last = p_last->p_next;    *ppp_last = &p_last->p_next;}static inline void block_ChainRelease( block_t *p_block ){    while( p_block )    {        block_t *p_next = p_block->p_next;        block_Release( p_block );        p_block = p_next;    }}static size_t block_ChainExtract( block_t *p_list, void *p_data, size_t i_max ){    size_t  i_total = 0;    uint8_t *p = (uint8_t*)p_data;    while( p_list && i_max )    {        size_t i_copy = __MIN( i_max, p_list->i_buffer );        memcpy( p, p_list->p_buffer, i_copy );        i_max   -= i_copy;        i_total += i_copy;        p       += i_copy;        p_list = p_list->p_next;    }    return i_total;}static inline void block_ChainProperties( block_t *p_list, int *pi_count, size_t *pi_size, mtime_t *pi_length ){    size_t i_size = 0;    mtime_t i_length = 0;    int i_count = 0;    while( p_list )    {        i_size += p_list->i_buffer;        i_length += p_list->i_length;        i_count++;        p_list = p_list->p_next;    }    if( pi_size )        *pi_size = i_size;    if( pi_length )        *pi_length = i_length;    if( pi_count )        *pi_count = i_count;}static inline block_t *block_ChainGather( block_t *p_list ){    size_t  i_total = 0;    mtime_t i_length = 0;    block_t *g;    if( p_list->p_next == NULL )        return p_list;  /* Already gathered */    block_ChainProperties( p_list, NULL, &i_total, &i_length );    g = block_Alloc( i_total );    block_ChainExtract( p_list, g->p_buffer, g->i_buffer );    g->i_flags = p_list->i_flags;    g->i_pts   = p_list->i_pts;    g->i_dts   = p_list->i_dts;    g->i_length = i_length;    /* free p_list */    block_ChainRelease( p_list );    return g;}/**************************************************************************** * Fifos of blocks. **************************************************************************** * - block_FifoNew : create and init a new fifo * - block_FifoRelease : destroy a fifo and free all blocks in it. * - block_FifoEmpty : free all blocks in a fifo * - block_FifoPut : put a block * - block_FifoGet : get a packet from the fifo (and wait if it is empty) * - block_FifoShow : show the first packet of the fifo (and wait if *      needed), be carefull, you can use it ONLY if you are sure to be the *      only one getting data from the fifo. * - block_FifoCount : how many packets are waiting in the fifo * - block_FifoSize : how many cumulated bytes are waiting in the fifo * - block_FifoWake : wake ups a thread with block_FifoGet() = NULL *   (this is used to wakeup a thread when there is no data to queue) * * block_FifoGet and block_FifoShow are cancellation points. ****************************************************************************/VLC_EXPORT( block_fifo_t *, block_FifoNew,      ( void ) LIBVLC_USED );VLC_EXPORT( void,           block_FifoRelease,  ( block_fifo_t * ) );/* TODO: do we need to export this? */void block_FifoPace (block_fifo_t *fifo, size_t max_depth, size_t max_size);VLC_EXPORT( void,           block_FifoEmpty,    ( block_fifo_t * ) );VLC_EXPORT( size_t,         block_FifoPut,      ( block_fifo_t *, block_t * ) );VLC_EXPORT( void,           block_FifoWake,     ( block_fifo_t * ) );VLC_EXPORT( block_t *,      block_FifoGet,      ( block_fifo_t * ) LIBVLC_USED );VLC_EXPORT( block_t *,      block_FifoShow,     ( block_fifo_t * ) );VLC_EXPORT( size_t,         block_FifoSize,     ( const block_fifo_t *p_fifo ) LIBVLC_USED );VLC_EXPORT( size_t,         block_FifoCount,    ( const block_fifo_t *p_fifo ) LIBVLC_USED );#endif /* VLC_BLOCK_H */