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/*****************************************************************************
* vlc_frame.h: frame management functions
*****************************************************************************
* Copyright (C) 2003 VLC authors and VideoLAN
*
* 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 Lesser General Public License as published by
* the Free Software Foundation; either version 2.1 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 Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser 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_FRAME_H
#define VLC_FRAME_H 1
#include <vlc_tick.h>
struct vlc_ancillary;
typedef uint32_t vlc_ancillary_id;
/**
* \defgroup frame Frames
* \ingroup input
*
* Frames of binary data.
*
* @ref vlc_frame_t is a generic structure to represent a binary blob within VLC.
* The primary goal of the structure is to avoid memory copying as data is
* passed around. It is notably used between the \ref demux, the packetizer
* (if present) and the \ref decoder, and for audio, between the \ref decoder,
* the audio filters, and the \ref audio_output.
*
* @{
* \file
* Frames definition and functions
*/
#include <sys/types.h> /* for ssize_t */
/****************************************************************************
* frame:
****************************************************************************
* - 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 VLC_TICK_INVALID, it means no pts/dts
* - i_length: length in microsecond of the packet, can be null except in the
* sout where it is mandatory.
*
* - i_buffer number of valid data pointed by p_buffer
* you can freely decrease it but never increase it yourself
* (use vlc_frame_Realloc)
* - p_buffer: pointer over data. You should never overwrite it, you can
* only increment it to skip data, in others cases use vlc_frame_Realloc
* (don't duplicate yourself in a bigger buffer, vlc_frame_Realloc is
* optimised for preheader/postdata increase)
****************************************************************************/
typedef struct vlc_frame_t vlc_frame_t;
/** The content doesn't follow the last frame, possible some frames in between
* have been lost */
#define VLC_FRAME_FLAG_DISCONTINUITY 0x0001
/** Intra frame */
#define VLC_FRAME_FLAG_TYPE_I 0x0002
/** Inter frame with backward reference only */
#define VLC_FRAME_FLAG_TYPE_P 0x0004
/** Inter frame with backward and forward reference */
#define VLC_FRAME_FLAG_TYPE_B 0x0008
/** For inter frame when you don't know the real type */
#define VLC_FRAME_FLAG_TYPE_PB 0x0010
/** Warn that this frame is a header one */
#define VLC_FRAME_FLAG_HEADER 0x0020
/** This frame contains the last part of a sequence */
#define VLC_FRAME_FLAG_END_OF_SEQUENCE 0x0040
/** This frame is scrambled */
#define VLC_FRAME_FLAG_SCRAMBLED 0x0100
/** This frame has to be decoded but not be displayed */
#define VLC_FRAME_FLAG_PREROLL 0x0200
/** This frame is corrupted and/or there is data loss */
#define VLC_FRAME_FLAG_CORRUPTED 0x0400
/** This frame is last of its access unit */
#define VLC_FRAME_FLAG_AU_END 0x0800
/** This frame contains an interlaced picture with top field stored first */
#define VLC_FRAME_FLAG_TOP_FIELD_FIRST 0x1000
/** This frame contains an interlaced picture with bottom field stored first */
#define VLC_FRAME_FLAG_BOTTOM_FIELD_FIRST 0x2000
/** This frame contains a single field from interlaced picture. */
#define VLC_FRAME_FLAG_SINGLE_FIELD 0x4000
/** This frame contains an interlaced picture */
#define VLC_FRAME_FLAG_INTERLACED_MASK \
(VLC_FRAME_FLAG_TOP_FIELD_FIRST|VLC_FRAME_FLAG_BOTTOM_FIELD_FIRST|VLC_FRAME_FLAG_SINGLE_FIELD)
#define VLC_FRAME_FLAG_TYPE_MASK \
(VLC_FRAME_FLAG_TYPE_I|VLC_FRAME_FLAG_TYPE_P|VLC_FRAME_FLAG_TYPE_B|VLC_FRAME_FLAG_TYPE_PB)
/* These are for input core private usage only */
#define VLC_FRAME_FLAG_CORE_PRIVATE_MASK 0x00ff0000
#define VLC_FRAME_FLAG_CORE_PRIVATE_SHIFT 16
/* These are for module private usage only */
#define VLC_FRAME_FLAG_PRIVATE_MASK 0xff000000
#define VLC_FRAME_FLAG_PRIVATE_SHIFT 24
struct vlc_frame_callbacks
{
void (*free)(vlc_frame_t *);
};
struct vlc_frame_t
{
vlc_frame_t *p_next;
uint8_t *p_buffer; /**< Payload start */
size_t i_buffer; /**< Payload length */
uint8_t *p_start; /**< Buffer start */
size_t i_size; /**< Buffer total size */
uint32_t i_flags;
unsigned i_nb_samples; /* Used for audio */
vlc_tick_t i_pts;
vlc_tick_t i_dts;
vlc_tick_t i_length;
/** Private ancillary struct. Don't use it directly, but use it via
* vlc_frame_AttachAncillary() and vlc_frame_GetAncillary(). */
struct vlc_ancillary **priv_ancillaries;
const struct vlc_frame_callbacks *cbs;
};
/**
* Initializes a custom frame.
*
* This function initialize a frame of timed data allocated by custom means.
* This allows passing data without copying even if the data has been allocated
* with unusual means or outside of LibVLC.
*
* Normally, frames are allocated and initialized by vlc_frame_Alloc() instead.
*
* @param frame allocated frame structure to initialize
* @param cbs structure of custom callbacks to handle the frame [IN]
* @param base start address of the frame data
* @param length byte length of the frame data
*
* @return @c frame (this function cannot fail)
*/
VLC_API vlc_frame_t *vlc_frame_Init(vlc_frame_t *frame,
const struct vlc_frame_callbacks *cbs,
void *base, size_t length);
/**
* Creates a custom frame.
*
* This function initialize a frame of timed data allocated by custom means.
* This allows passing data without copying even if the data has been allocated
* with unusual means or outside of LibVLC.
*
* Normally, frames are allocated and initialized by vlc_frame_Alloc() instead.
*
* @param cbs structure of custom callbacks to handle the frame [IN]
* @param base start address of the frame data
* @param length byte length of the frame data
*
* @return the created frame, or NULL on memory error.
*/
VLC_API vlc_frame_t *vlc_frame_New(const struct vlc_frame_callbacks *cbs,
void *base, size_t length);
/**
* Allocates a frame.
*
* Creates a new frame with the requested size.
* The frame must be released with vlc_frame_Release().
*
* @param size size in bytes (possibly zero)
* @return the created frame, or NULL on memory error.
*/
VLC_API vlc_frame_t *vlc_frame_Alloc(size_t size) VLC_USED VLC_MALLOC;
VLC_API vlc_frame_t *vlc_frame_TryRealloc(vlc_frame_t *, ssize_t pre, size_t body) VLC_USED;
/**
* Reallocates a frame.
*
* This function expands, shrinks or moves a data frame.
* In many cases, this function can return without any memory allocation by
* reusing spare buffer space. Otherwise, a new frame is created and data is
* copied.
*
* @param frame the frame to realloc, which will be freed after the call to
* this function
* @param pre count of bytes to prepend if positive,
* count of leading bytes to discard if negative
* @param body new bytes size of the frame
*
* @return the reallocated frame on success, NULL on error.
*
* @note Skipping leading bytes can be achieved directly by subtracting from
* vlc_frame_t.i_buffer and adding vlc_frame_t.p_buffer.
* @note Discard trailing bytes can be achieved directly by subtracting from
* vlc_frame_t.i_buffer.
* @note On error, the frame is discarded.
* To avoid that, use vlc_frame_TryRealloc() instead.
*/
VLC_API vlc_frame_t *
vlc_frame_Realloc(vlc_frame_t *frame, ssize_t pre, size_t body) VLC_USED;
/**
* Releases a frame.
*
* This function works for any @ref vlc_frame_t frame, regardless of the way it was
* allocated.
*
* @note
* If the frame is in a chain, this function does <b>not</b> release any
* subsequent frame in the chain. Use vlc_frame_ChainRelease() for that purpose.
*
* @param frame frame to release (cannot be NULL)
*/
VLC_API void vlc_frame_Release(vlc_frame_t *frame);
/**
* Attach an ancillary to the frame
*
* @warning the ancillary will be released only if the frame is allocated from
* a vlc_frame Alloc function (vlc_frame_Alloc(), vlc_frame_mmap_Alloc()...).
*
* @note Several ancillaries can be attached to a frame, but if two ancillaries
* are identified by the same ID, only the last one take precedence.
*
* @param frame the frame to attach an ancillary
* @param ancillary ancillary that will be held by the frame, can't be NULL
* @return VLC_SUCCESS in case of success, VLC_ENOMEM in case of alloc error
*/
VLC_API int
vlc_frame_AttachAncillary(vlc_frame_t *frame, struct vlc_ancillary *ancillary);
/**
* Return the ancillary identified by an ID
*
* @param frame the frame to read the ancillary from
* @param id id of ancillary to request
* @return the ancillary or NULL if the ancillary for that particular id is
* not present
*/
VLC_API struct vlc_ancillary *
vlc_frame_GetAncillary(vlc_frame_t *frame, vlc_ancillary_id id);
/**
* Copy frame properties from src to dst
*
* Copy i_flags, i_nb_samples, i_dts, i_pts, and i_length.
*
* @note if src has an ancillary, the ancillary will be copied and refcounted
* to dst.
*
* @param dst the frame to copy properties into
* @param src the frame to copy properties from
*/
VLC_API void vlc_frame_CopyProperties( vlc_frame_t *dst, const vlc_frame_t *src );
/**
* Duplicates a frame.
*
* Creates a writeable duplicate of a frame.
*
* @return the duplicate on success, NULL on error.
*/
VLC_USED
static inline vlc_frame_t *vlc_frame_Duplicate( const vlc_frame_t *frame )
{
vlc_frame_t *p_dup = vlc_frame_Alloc( frame->i_buffer );
if( p_dup == NULL )
return NULL;
vlc_frame_CopyProperties( p_dup, frame );
memcpy( p_dup->p_buffer, frame->p_buffer, frame->i_buffer );
return p_dup;
}
/**
* Wraps heap in a frame.
*
* Creates a @ref vlc_frame_t out of an existing heap allocation.
* This is provided by LibVLC so that manually heap-allocated frames can safely
* be deallocated even after the origin plugin has been unloaded from memory.
*
* When vlc_frame_Release() is called, VLC will free() the specified pointer.
*
* @param addr base address of the heap allocation (will be free()'d)
* @param length bytes length of the heap allocation
* @return NULL in case of error (ptr free()'d in that case), or a valid
* vlc_frame_t pointer.
*/
VLC_API vlc_frame_t *vlc_frame_heap_Alloc(void *addr, size_t length) VLC_USED VLC_MALLOC;
/**
* Wraps a memory mapping in a frame
*
* Creates a @ref vlc_frame_t from a virtual address memory mapping (mmap).
* This is provided by LibVLC so that mmap frames can safely be deallocated
* even after the allocating plugin has been unloaded from memory.
*
* @param addr base address of the mapping (as returned by mmap)
* @param length length (bytes) of the mapping (as passed to mmap)
* @return NULL if addr is MAP_FAILED, or an error occurred (in the later
* case, munmap(addr, length) is invoked before returning).
*/
VLC_API vlc_frame_t *vlc_frame_mmap_Alloc(void *addr, size_t length) VLC_USED VLC_MALLOC;
/**
* Wraps a System V memory segment in a frame
*
* Creates a @ref vlc_frame_t from a System V shared memory segment (shmget()).
* This is provided by LibVLC so that segments can safely be deallocated
* even after the allocating plugin has been unloaded from memory.
*
* @param addr base address of the segment (as returned by shmat())
* @param length length (bytes) of the segment (as passed to shmget())
* @return NULL if an error occurred (in that case, shmdt(addr) is invoked
* before returning NULL).
*/
VLC_API vlc_frame_t * vlc_frame_shm_Alloc(void *addr, size_t length) VLC_USED VLC_MALLOC;
/**
* Maps a file handle in memory.
*
* Loads a file into a frame of memory through a file descriptor.
* If possible a private file mapping is created. Otherwise, the file is read
* normally. This function is a cancellation point.
*
* @note On 32-bits platforms,
* this function will not work for very large files,
* due to memory space constraints.
*
* @param fd file descriptor to load from
* @param write If true, request a read/write private mapping.
* If false, request a read-only potentially shared mapping.
*
* @return a new frame with the file content at p_buffer, and file length at
* i_buffer (release it with vlc_frame_Release()), or NULL upon error (see errno).
*/
VLC_API vlc_frame_t *vlc_frame_File(int fd, bool write) VLC_USED VLC_MALLOC;
/**
* Maps a file in memory.
*
* Loads a file into a frame of memory from a path to the file.
* See also vlc_frame_File().
*
* @param path the file path to load the memory block from
* @param write If true, request a read/write private mapping.
* If false, request a read-only potentially shared mapping.
*/
VLC_API vlc_frame_t *
vlc_frame_FilePath(const char *path, bool write)
VLC_USED VLC_MALLOC;
static inline void vlc_frame_Cleanup (void *frame)
{
vlc_frame_Release ((vlc_frame_t *)frame);
}
#define vlc_frame_cleanup_push( frame ) vlc_cleanup_push (vlc_frame_Cleanup, frame)
/**
* \defgroup vlc_frame_chain Frame chain
* @{
*/
/**
* Appends a @ref vlc_frame_t to the chain
*
* The given frame is appended to the last frame of the given chain.
*
* @attention
* Using this function on long chains or repeatedly calling it
* to append a lot of frames can be slow, as it has to iterate the
* whole chain to append the frame.
* In these cases @ref vlc_frame_ChainLastAppend should be used.
*
* @param pp_list Pointer to the vlc_frame_t chain
* @param frame The vlc_frame_t to append (can be NULL)
*
* @see vlc_frame_ChainLastAppend()
*
* Example:
* @code{.c}
* vlc_frame_t *p_chain = NULL;
*
* vlc_frame_ChainAppend(&p_chain, p_frame);
* @endcode
*/
static inline void vlc_frame_ChainAppend( vlc_frame_t **pp_list, vlc_frame_t *frame )
{
if( *pp_list == NULL )
{
*pp_list = frame;
}
else
{
vlc_frame_t *p = *pp_list;
while( p->p_next ) p = p->p_next;
p->p_next = frame;
}
}
/**
* Appends a @ref vlc_frame_t to the last frame pointer and update it
*
* Uses a pointer over a pointer to p_next of the last frame of the frame chain
* to append a frame at the end of the chain and updates the pointer to the new
* last frame's @c p_next. If the appended frame is itself a chain, it is iterated
* till the end to correctly update @c ppp_last.
*
* @param[in,out] ppp_last Pointer to pointer to the end of the chain
* (The vlc_frame_t::p_next of the last vlc_frame_t in the chain)
* @param frame The vlc_frame_t to append
*
* Example:
* @code{.c}
* vlc_frame_t *p_frame = NULL;
* vlc_frame_t **pp_frame_last = &p_frame;
*
* vlc_frame_ChainLastAppend(&pp_frame_last, p_other_frame);
* @endcode
*/
static inline void vlc_frame_ChainLastAppend( vlc_frame_t ***ppp_last, vlc_frame_t *frame )
{
vlc_frame_t *p_last = frame;
**ppp_last = frame;
while( p_last->p_next ) p_last = p_last->p_next;
*ppp_last = &p_last->p_next;
}
/**
* Releases a chain of blocks
*
* The frame pointed to by frame and all following frames in the
* chain are released.
*
* @param frame Pointer to first vlc_frame_t of the chain to release
*
* @see vlc_frame_Release()
*/
static inline void vlc_frame_ChainRelease( vlc_frame_t *frame )
{
while( frame )
{
vlc_frame_t *p_next = frame->p_next;
vlc_frame_Release( frame );
frame = p_next;
}
}
/**
* Extracts data from a chain of frames
*
* Copies the specified amount of data from the chain into the given buffer.
* If the data in the chain is less than the maximum amount given, the remainder
* of the buffer is not modified.
*
* @param p_list Pointer to the first vlc_frame_t of the chain to copy from
* @param[out] p_data Destination buffer to copy the data to
* @param i_max Number of bytes to copy
* @return Number of bytes actually copied
*
* @see vlc_frame_ChainGather()
*/
static size_t vlc_frame_ChainExtract( vlc_frame_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;
}
/**
* Retrieves chain properties
*
* Can be used to retrieve count of frames, number of bytes and the duration
* of the chain.
*
* @param p_list Pointer to the first vlc_frame_t of the chain
* @param[out] pi_count Pointer to count of frames in the chain (may be NULL)
* @param[out] pi_size Pointer to number of bytes in the chain (may be NULL)
* @param[out] pi_length Pointer to length (duration) of the chain (may be NULL)
*/
static inline void vlc_frame_ChainProperties( const vlc_frame_t *p_list, int *pi_count, size_t *pi_size, vlc_tick_t *pi_length )
{
size_t i_size = 0;
vlc_tick_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;
}
/**
* Gathers a chain into a single vlc_frame_t
*
* All frames in the chain are gathered into a single vlc_frame_t and the
* original chain is released.
*
* @param p_list Pointer to the first vlc_frame_t of the chain to gather
* @return Returns a pointer to a new vlc_frame_t or NULL if the frame can not
* be allocated, in which case the original chain is not released.
* If the chain pointed to by p_list is already gathered, a pointer
* to it is returned and no new frame will be allocated.
*
* @see vlc_frame_ChainExtract()
*/
static inline vlc_frame_t *vlc_frame_ChainGather( vlc_frame_t *p_list )
{
size_t i_total = 0;
vlc_tick_t i_length = 0;
vlc_frame_t *g;
if( p_list->p_next == NULL )
return p_list; /* Already gathered */
vlc_frame_ChainProperties( p_list, NULL, &i_total, &i_length );
g = vlc_frame_Alloc( i_total );
if( !g )
return NULL;
vlc_frame_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 */
vlc_frame_ChainRelease( p_list );
return g;
}
/**
* @}
* \defgroup block_fifo Block FIFO
* Thread-safe block queue functions
* @{
*/
#include <vlc_queue.h>
/**
* Creates a thread-safe FIFO queue of blocks.
*
* See also vlc_fifo_Put() and vlc_fifo_Get().
* The created queue must be deleted with vlc_fifo_Delete().
*
* @return the FIFO or NULL on memory error
*/
VLC_API vlc_fifo_t *vlc_fifo_New(void) VLC_USED VLC_MALLOC;
/**
* Delete a FIFO created by vlc_fifo_New().
*
* @note Any queued blocks are also deleted.
* @warning No other threads may be using the FIFO when this function is
* called. Otherwise, undefined behaviour will occur.
*/
VLC_API void vlc_fifo_Delete(vlc_fifo_t *);
/**
* Dequeue the first block from the FIFO. If necessary, wait until there is
* one block in the queue. This function is (always) cancellation point.
*
* @return a valid block
*/
VLC_API vlc_frame_t *vlc_fifo_Get(vlc_fifo_t *) VLC_USED;
/**
* Peeks the first block in the FIFO.
*
* @warning This function leaves the block in the FIFO.
* You need to protect against concurrent threads who could dequeue the block.
* Preferably, there should be only one thread reading from the FIFO.
*
* @warning This function is undefined if the FIFO is empty.
*
* @return a valid block.
*/
VLC_API vlc_frame_t *vlc_fifo_Show(vlc_fifo_t *);
static inline vlc_queue_t *vlc_fifo_queue(const vlc_fifo_t *fifo)
{
return (vlc_queue_t *)fifo;
}
/**
* Locks a block FIFO.
*
* No more than one thread can lock the FIFO at any given
* time, and no other thread can modify the FIFO while it is locked.
* vlc_fifo_Unlock() releases the lock.
*
* @note If the FIFO is already locked by another thread, this function waits.
* This function is not a cancellation point.
*
* @warning Recursively locking a single FIFO is undefined. Locking more than
* one FIFO at a time may lead to lock inversion; mind the locking order.
*/
static inline void vlc_fifo_Lock(vlc_fifo_t *fifo)
{
vlc_queue_Lock(vlc_fifo_queue(fifo));
}
/**
* Unlocks a block FIFO.
*
* The calling thread must have locked the FIFO previously with
* vlc_fifo_Lock(). Otherwise, the behaviour is undefined.
*
* @note This function is not a cancellation point.
*/
static inline void vlc_fifo_Unlock(vlc_fifo_t *fifo)
{
vlc_queue_Unlock(vlc_fifo_queue(fifo));
}
/**
* Wakes up one thread waiting on the FIFO, if any.
*
* @note This function is not a cancellation point.
*
* @warning For race-free operations, the FIFO should be locked by the calling
* thread. The function can be called on a unlocked FIFO however.
*/
static inline void vlc_fifo_Signal(vlc_fifo_t *fifo)
{
vlc_queue_Signal(vlc_fifo_queue(fifo));
}
/**
* Waits on the FIFO.
*
* Atomically unlocks the FIFO and waits until one thread signals the FIFO,
* then locks the FIFO again. A signal can be sent by queueing a block to the
* previously empty FIFO or by calling vlc_fifo_Signal() directly.
* This function may also return spuriously at any moment.
*
* @note This function is a cancellation point. In case of cancellation, the
* the FIFO will be locked before cancellation cleanup handlers are processed.
*/
static inline void vlc_fifo_Wait(vlc_fifo_t *fifo)
{
vlc_queue_Wait(vlc_fifo_queue(fifo));
}
static inline void vlc_fifo_WaitCond(vlc_fifo_t *fifo, vlc_cond_t *condvar)
{
vlc_queue_t *q = vlc_fifo_queue(fifo);
vlc_cond_wait(condvar, &q->lock);
}
/**
* Queues a linked-list of blocks into a locked FIFO.
*
* @param fifo a fifo object locked with ::vlc_fifo_Lock()
* @param block the head of the list of blocks
* (if NULL, this function has no effects)
*
* @note This function is not a cancellation point.
*
* @warning The FIFO must be locked by the calling thread using
* vlc_fifo_Lock(). Otherwise behaviour is undefined.
*/
VLC_API void vlc_fifo_QueueUnlocked(vlc_fifo_t *fifo, vlc_frame_t *block);
/**
* Dequeues the first block from a locked FIFO, if any.
*
* @note This function is not a cancellation point.
*
* @warning The FIFO must be locked by the calling thread using
* vlc_fifo_Lock(). Otherwise behaviour is undefined.
*
* @return the first block in the FIFO or NULL if the FIFO is empty
*/
VLC_API vlc_frame_t *vlc_fifo_DequeueUnlocked(vlc_fifo_t *) VLC_USED;
/**
* Dequeues the all blocks from a locked FIFO.
*
* This is equivalent to calling vlc_fifo_DequeueUnlocked() repeatedly until
* the FIFO is emptied, but this function is much faster.
*
* @note This function is not a cancellation point.
*
* @warning The FIFO must be locked by the calling thread using
* vlc_fifo_Lock(). Otherwise behaviour is undefined.
*
* @return a linked-list of all blocks in the FIFO (possibly NULL)
*/
VLC_API vlc_frame_t *vlc_fifo_DequeueAllUnlocked(vlc_fifo_t *) VLC_USED;
/**
* Counts blocks in a FIFO.
*
* Checks how many blocks are queued in a locked FIFO.
*
* @note This function is not cancellation point.
*
* @warning The FIFO must be locked by the calling thread using
* vlc_fifo_Lock(). Otherwise behaviour is undefined.
*
* @return the number of blocks in the FIFO (zero if it is empty)
*/
VLC_API size_t vlc_fifo_GetCount(const vlc_fifo_t *) VLC_USED;
/**
* Counts bytes in a FIFO.
*
* Checks how many bytes are queued in a locked FIFO.
*
* @note This function is not cancellation point.
*
* @warning The FIFO must be locked by the calling thread using
* vlc_fifo_Lock(). Otherwise behaviour is undefined.
*
* @return the total number of bytes
*
* @note Zero bytes does not necessarily mean that the FIFO is empty since
* a block could contain zero bytes. Use vlc_fifo_GetCount() to determine if
* a FIFO is empty.
*/
VLC_API size_t vlc_fifo_GetBytes(const vlc_fifo_t *) VLC_USED;
/**
* Checks whether the vlc_fifo_t object is being locked.
*
* This function checks if the calling thread holds a given vlc_fifo_t
* object. It has no side effects and is essentially intended for run-time
* debugging.
*
* @note This function is the vlc_fifo_t equivalent of vlc_mutex_held.
*
* @note To assert that the calling thread holds a lock, the helper macro
* vlc_fifo_Assert() should be used instead of this function.
*
* @retval false the fifo is not locked by the calling thread
* @retval true the fifo is locked by the calling thread
*/
VLC_API bool vlc_fifo_Held(const vlc_fifo_t *fifo) VLC_USED;
/**
* Asserts that a vlc_fifo_t is locked by the calling thread.
*/
#define vlc_fifo_Assert(fifo) assert(vlc_fifo_Held(fifo))
VLC_USED static inline bool vlc_fifo_IsEmpty(const vlc_fifo_t *fifo)
{
return vlc_queue_IsEmpty(vlc_fifo_queue(fifo));
}
static inline void vlc_fifo_Cleanup(void *fifo)
{
vlc_fifo_Unlock((vlc_fifo_t *)fifo);
}
#define vlc_fifo_CleanupPush(fifo) vlc_cleanup_push(vlc_fifo_Cleanup, fifo)
/**
* Clears all blocks in a FIFO.
*/
static inline void vlc_fifo_Empty(vlc_fifo_t *fifo)
{
vlc_frame_t *block;
vlc_fifo_Lock(fifo);
block = vlc_fifo_DequeueAllUnlocked(fifo);
vlc_fifo_Unlock(fifo);
vlc_frame_ChainRelease(block);
}
/**
* Immediately queue one block at the end of a FIFO.
*
* @param fifo queue
* @param block head of a block list to queue (may be NULL)
*/
static inline void vlc_fifo_Put(vlc_fifo_t *fifo, vlc_frame_t *block)
{
vlc_fifo_Lock(fifo);
vlc_fifo_QueueUnlocked(fifo, block);
vlc_fifo_Unlock(fifo);
}
/* FIXME: not (really) thread-safe */
VLC_USED VLC_DEPRECATED
static inline size_t vlc_fifo_Size (vlc_fifo_t *fifo)
{
size_t size;
vlc_fifo_Lock(fifo);
size = vlc_fifo_GetBytes(fifo);
vlc_fifo_Unlock(fifo);
return size;
}
/* FIXME: not (really) thread-safe */
VLC_USED VLC_DEPRECATED
static inline size_t vlc_fifo_Count (vlc_fifo_t *fifo)
{
size_t depth;
vlc_fifo_Lock(fifo);
depth = vlc_fifo_GetCount(fifo);
vlc_fifo_Unlock(fifo);
return depth;
}
/** @} */
/** @} */
#endif /* VLC_FRAME_H */
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