SPA Buffers

Buffers describe the data and metadata that is exchanged between ports of a node. More...

Data Structures
struct	spa_buffer_alloc_info
	information about the buffer layout More...
struct	spa_chunk
	Chunk of memory, can change for each buffer. More...
struct	spa_data
	Data for a buffer this stays constant for a buffer. More...
struct	spa_buffer
	A Buffer. More...
struct	spa_meta
	A metadata element. More...
struct	spa_meta_header
	Describes essential buffer header metadata such as flags and timestamps. More...
struct	spa_meta_region
	metadata structure for Region or an array of these for RegionArray More...
struct	spa_meta_bitmap
	Bitmap information. More...
struct	spa_meta_cursor
	Cursor information. More...
struct	spa_meta_control
	a timed set of events associated with the buffer More...
struct	spa_meta_busy
	a busy counter for the buffer More...

Macros
#define	spa_meta_first(m)   ((m)->data)
#define	spa_meta_end(m)   SPA_PTROFF((m)->data,(m)->size,void)
#define	spa_meta_check(p, m)   (SPA_PTROFF(p,sizeof(*p),void) <= spa_meta_end(m))
#define	spa_meta_region_is_valid(m)   ((m)->region.size.width != 0 && (m)->region.size.height != 0)
#define	spa_meta_for_each(pos, meta)
	iterate all the items in a metadata More...
#define	spa_meta_bitmap_is_valid(m)   ((m)->format != 0)
#define	spa_meta_cursor_is_valid(m)   ((m)->id != 0)
#define	SPA_TYPE_INFO_Buffer   SPA_TYPE_INFO_POINTER_BASE "Buffer"
#define	SPA_TYPE_INFO_BUFFER_BASE   SPA_TYPE_INFO_Buffer ":"
#define	SPA_TYPE_INFO_Data   SPA_TYPE_INFO_ENUM_BASE "Data"
	Buffers contain data of a certain type. More...
#define	SPA_TYPE_INFO_DATA_BASE   SPA_TYPE_INFO_Data ":"
#define	SPA_TYPE_INFO_DATA_Fd   SPA_TYPE_INFO_DATA_BASE "Fd"
	base type for fd based memory More...
#define	SPA_TYPE_INFO_DATA_FD_BASE   SPA_TYPE_INFO_DATA_Fd ":"
#define	SPA_TYPE_INFO_Meta   SPA_TYPE_INFO_POINTER_BASE "Meta"
#define	SPA_TYPE_INFO_META_BASE   SPA_TYPE_INFO_Meta ":"
#define	SPA_TYPE_INFO_META_Array   SPA_TYPE_INFO_META_BASE "Array"
#define	SPA_TYPE_INFO_META_ARRAY_BASE   SPA_TYPE_INFO_META_Array ":"
#define	SPA_TYPE_INFO_META_Region   SPA_TYPE_INFO_META_BASE "Region"
#define	SPA_TYPE_INFO_META_REGION_BASE   SPA_TYPE_INFO_META_Region ":"
#define	SPA_TYPE_INFO_META_ARRAY_Region   SPA_TYPE_INFO_META_ARRAY_BASE "Region"
#define	SPA_TYPE_INFO_META_ARRAY_REGION_BASE   SPA_TYPE_INFO_META_ARRAY_Region ":"

Enumerations
enum	spa_data_type {   SPA_DATA_Invalid, SPA_DATA_MemPtr, SPA_DATA_MemFd, SPA_DATA_DmaBuf,   SPA_DATA_MemId, _SPA_DATA_LAST }
enum	spa_meta_type {   SPA_META_Invalid, SPA_META_Header, SPA_META_VideoCrop, SPA_META_VideoDamage,   SPA_META_Bitmap, SPA_META_Cursor, SPA_META_Control, SPA_META_Busy,   _SPA_META_LAST }

Functions
int	spa_buffer_alloc_fill_info (struct spa_buffer_alloc_info *info, uint32_t n_metas, struct spa_meta metas[], uint32_t n_datas, struct spa_data datas[], uint32_t data_aligns[])
	Fill buffer allocation information. More...
struct spa_buffer *	spa_buffer_alloc_layout (struct spa_buffer_alloc_info *info, void *skel_mem, void *data_mem)
	Fill skeleton and data according to the allocation info. More...
int	spa_buffer_alloc_layout_array (struct spa_buffer_alloc_info *info, uint32_t n_buffers, struct spa_buffer *buffers[], void *skel_mem, void *data_mem)
	Layout an array of buffers. More...
struct spa_buffer **	spa_buffer_alloc_array (uint32_t n_buffers, uint32_t flags, uint32_t n_metas, struct spa_meta metas[], uint32_t n_datas, struct spa_data datas[], uint32_t data_aligns[])
	Allocate an array of buffers. More...
struct spa_meta *	spa_buffer_find_meta (const struct spa_buffer *b, uint32_t type)
	Find metadata in a buffer. More...
void *	spa_buffer_find_meta_data (const struct spa_buffer *b, uint32_t type, size_t size)

Variables
const struct spa_type_info	spa_type_data_type []
const struct spa_type_info	spa_type_meta_type []

Detailed Description

Buffers describe the data and metadata that is exchanged between ports of a node.

Macro Definition Documentation

spa_meta_bitmap_is_valid

#define spa_meta_bitmap_is_valid

(

m

)

((m)->format != 0)

spa_meta_check

#define spa_meta_check	(		p,
			m
	)		(SPA_PTROFF(p,sizeof(*p),void) <= spa_meta_end(m))

spa_meta_cursor_is_valid

#define spa_meta_cursor_is_valid

(

m

)

((m)->id != 0)

spa_meta_end

#define spa_meta_end

(

m

)

SPA_PTROFF((m)->data,(m)->size,void)

spa_meta_first

#define spa_meta_first

(

m

)

((m)->data)

spa_meta_for_each

#define spa_meta_for_each	(		pos,
			meta
	)

Value:

        for (pos = (__typeof(pos))spa_meta_first(meta);                 \
            spa_meta_check(pos, meta);                                  \
            (pos)++)

iterate all the items in a metadata

spa_meta_region_is_valid

#define spa_meta_region_is_valid

(

m

)

((m)->region.size.width != 0 && (m)->region.size.height != 0)

SPA_TYPE_INFO_Buffer

#define SPA_TYPE_INFO_Buffer   SPA_TYPE_INFO_POINTER_BASE "Buffer"

SPA_TYPE_INFO_BUFFER_BASE

#define SPA_TYPE_INFO_BUFFER_BASE   SPA_TYPE_INFO_Buffer ":"

SPA_TYPE_INFO_Data

#define SPA_TYPE_INFO_Data   SPA_TYPE_INFO_ENUM_BASE "Data"

Buffers contain data of a certain type.

SPA_TYPE_INFO_DATA_BASE

#define SPA_TYPE_INFO_DATA_BASE   SPA_TYPE_INFO_Data ":"

SPA_TYPE_INFO_DATA_Fd

#define SPA_TYPE_INFO_DATA_Fd   SPA_TYPE_INFO_DATA_BASE "Fd"

base type for fd based memory

SPA_TYPE_INFO_DATA_FD_BASE

#define SPA_TYPE_INFO_DATA_FD_BASE   SPA_TYPE_INFO_DATA_Fd ":"

SPA_TYPE_INFO_Meta

#define SPA_TYPE_INFO_Meta   SPA_TYPE_INFO_POINTER_BASE "Meta"

SPA_TYPE_INFO_META_Array

#define SPA_TYPE_INFO_META_Array   SPA_TYPE_INFO_META_BASE "Array"

SPA_TYPE_INFO_META_ARRAY_BASE

#define SPA_TYPE_INFO_META_ARRAY_BASE   SPA_TYPE_INFO_META_Array ":"

SPA_TYPE_INFO_META_ARRAY_Region

#define SPA_TYPE_INFO_META_ARRAY_Region   SPA_TYPE_INFO_META_ARRAY_BASE "Region"

SPA_TYPE_INFO_META_ARRAY_REGION_BASE

#define SPA_TYPE_INFO_META_ARRAY_REGION_BASE   SPA_TYPE_INFO_META_ARRAY_Region ":"

SPA_TYPE_INFO_META_BASE

#define SPA_TYPE_INFO_META_BASE   SPA_TYPE_INFO_Meta ":"

SPA_TYPE_INFO_META_Region

#define SPA_TYPE_INFO_META_Region   SPA_TYPE_INFO_META_BASE "Region"

SPA_TYPE_INFO_META_REGION_BASE

#define SPA_TYPE_INFO_META_REGION_BASE   SPA_TYPE_INFO_META_Region ":"

Enumeration Type Documentation

spa_data_type

enum spa_data_type

Enumerator
SPA_DATA_Invalid
SPA_DATA_MemPtr	pointer to memory, the data field in struct spa_data is set.
SPA_DATA_MemFd	generic fd, mmap to get to memory
SPA_DATA_DmaBuf	fd to dmabuf memory
SPA_DATA_MemId	memory is identified with an id
_SPA_DATA_LAST	not part of ABI

spa_meta_type

enum spa_meta_type

Enumerator
SPA_META_Invalid
SPA_META_Header	struct spa_meta_header
SPA_META_VideoCrop	struct spa_meta_region with cropping data
SPA_META_VideoDamage	array of struct spa_meta_region with damage
SPA_META_Bitmap	struct spa_meta_bitmap
SPA_META_Cursor	struct spa_meta_cursor
SPA_META_Control	metadata contains a spa_meta_control associated with the data
SPA_META_Busy	don't write to buffer when count > 0
_SPA_META_LAST	not part of ABI/API

Function Documentation

spa_buffer_alloc_array()

struct spa_buffer** spa_buffer_alloc_array ( uint32_t  n_buffers, uint32_t  flags, uint32_t  n_metas, struct spa_meta  metas[], uint32_t  n_datas, struct spa_data  datas[], uint32_t  data_aligns[]  )

inline

Allocate an array of buffers.

Allocate n_buffers with the given metadata, memory and alignment information.

The buffer array, structures, data and metadata will all be allocated in one block of memory with the proper requested alignment.

Parameters

n_buffers	the number of buffers to create
flags	extra flags
n_metas	number of metadatas
metas	n_metas metadata specification
n_datas	number of datas
datas	n_datas memory specification
data_aligns	n_datas alignment specifications

Returns

an array of n_buffers pointers to struct SPA Buffers with the given metadata, data and alignment or NULL when allocation failed.

References spa_buffer_alloc_info::data_aligns, spa_buffer_alloc_info::datas, spa_buffer_alloc_info::flags, spa_buffer_alloc_info::max_align, spa_buffer_alloc_info::metas, spa_buffer_alloc_info::n_datas, spa_buffer_alloc_info::n_metas, spa_buffer_alloc_info::skel_size, spa_buffer_alloc_fill_info(), SPA_BUFFER_ALLOC_FLAG_INLINE_ALL, spa_buffer_alloc_layout_array(), SPA_PTR_ALIGN, and SPA_PTROFF.

spa_buffer_alloc_fill_info()

int spa_buffer_alloc_fill_info ( struct spa_buffer_alloc_info *  info, uint32_t  n_metas, struct spa_meta  metas[], uint32_t  n_datas, struct spa_data  datas[], uint32_t  data_aligns[]  )

inline

Fill buffer allocation information.

Fill info with allocation information needed to allocate buffers with the given number of metadata and data members.

The required size of the skeleton (the struct spa_buffer) information and the memory (for the metadata, chunk and buffer memory) will be calculated.

The flags member in info should be configured before calling this functions.

Parameters

info	the information to fill
n_metas	the number of metadatas for the buffer
metas	an array of metadata items
n_datas	the number of datas for the buffer
datas	an array of n_datas items
data_aligns	n_datas alignments

Returns

0 on success.

References spa_buffer_alloc_info::chunk_size, spa_buffer_alloc_info::data_aligns, spa_buffer_alloc_info::data_size, spa_buffer_alloc_info::datas, spa_buffer_alloc_info::flags, spa_buffer_alloc_info::max_align, spa_data::maxsize, spa_buffer_alloc_info::mem_size, spa_buffer_alloc_info::meta_size, spa_buffer_alloc_info::metas, spa_buffer_alloc_info::n_datas, spa_buffer_alloc_info::n_metas, n_metas, spa_chunk::size, spa_buffer_alloc_info::skel_size, SPA_BUFFER_ALLOC_FLAG_INLINE_CHUNK, SPA_BUFFER_ALLOC_FLAG_INLINE_DATA, SPA_BUFFER_ALLOC_FLAG_INLINE_META, SPA_BUFFER_ALLOC_FLAG_NO_DATA, SPA_FLAG_IS_SET, SPA_MAX, and SPA_ROUND_UP_N.

Referenced by spa_buffer_alloc_array().

spa_buffer_alloc_layout()

struct spa_buffer* spa_buffer_alloc_layout ( struct spa_buffer_alloc_info *  info, void *  skel_mem, void *  data_mem  )

inline

Fill skeleton and data according to the allocation info.

Use the allocation info to create a struct SPA Buffers into skel_mem and data_mem.

Depending on the flags given when calling spa_buffer_alloc_fill_info(), the buffer meta, chunk and memory will be referenced in either skel_mem or data_mem.

Parameters

info	an allocation info
skel_mem	memory to hold the struct SPA Buffers and the pointers to meta, chunk and memory.
data_mem	memory to hold the meta, chunk and memory

Returns

a struct SPA Buffers in skel_mem

References spa_data::chunk, spa_data::data, spa_meta::data, spa_buffer_alloc_info::data_aligns, spa_buffer_alloc_info::datas, datas, spa_buffer_alloc_info::flags, spa_data::maxsize, spa_buffer_alloc_info::metas, metas, spa_buffer_alloc_info::n_datas, n_datas, spa_buffer_alloc_info::n_metas, n_metas, spa_chunk::size, spa_meta::size, SPA_BUFFER_ALLOC_FLAG_INLINE_CHUNK, SPA_BUFFER_ALLOC_FLAG_INLINE_DATA, SPA_BUFFER_ALLOC_FLAG_INLINE_META, SPA_BUFFER_ALLOC_FLAG_NO_DATA, SPA_FLAG_IS_SET, SPA_PTR_ALIGN, SPA_PTROFF, and SPA_ROUND_UP_N.

Referenced by spa_buffer_alloc_layout_array().

spa_buffer_alloc_layout_array()

int spa_buffer_alloc_layout_array ( struct spa_buffer_alloc_info *  info, uint32_t  n_buffers, struct spa_buffer *  buffers[], void *  skel_mem, void *  data_mem  )

inline

Layout an array of buffers.

Use the allocation info to layout the memory of an array of buffers.

skel_mem should point to at least info->skel_size * n_buffers bytes of memory. data_mem should point to at least info->mem_size * n_buffers bytes of memory.

Parameters

info	the allocation info for one buffer
n_buffers	the number of buffers to create
buffers	a array with space to hold n_buffers pointers to buffers
skel_mem	memory for the struct SPA Buffers
data_mem	memory for the meta, chunk, memory of the buffer if not inlined in the skeleton.

Returns

0 on success.

References spa_buffer_alloc_info::mem_size, spa_buffer_alloc_info::skel_size, spa_buffer_alloc_layout(), and SPA_PTROFF.

Referenced by spa_buffer_alloc_array().

spa_buffer_find_meta()

struct spa_meta* spa_buffer_find_meta ( const struct spa_buffer *  b, uint32_t  type  )

inline

Find metadata in a buffer.

References metas, n_metas, and spa_meta::type.

Referenced by spa_buffer_find_meta_data().

spa_buffer_find_meta_data()

void* spa_buffer_find_meta_data ( const struct spa_buffer *  b, uint32_t  type, size_t  size  )

inline

References spa_meta::data, spa_chunk::size, spa_meta::size, spa_buffer_find_meta(), and spa_meta::type.

Variable Documentation

spa_type_data_type

const struct spa_type_info spa_type_data_type[]

Initial value:

= {
        { SPA_DATA_Invalid, SPA_TYPE_Int, SPA_TYPE_INFO_DATA_BASE "Invalid", NULL },
        { SPA_DATA_MemPtr, SPA_TYPE_Int, SPA_TYPE_INFO_DATA_BASE "MemPtr", NULL },
        { SPA_DATA_MemFd, SPA_TYPE_Int, SPA_TYPE_INFO_DATA_FD_BASE "MemFd", NULL },
        { SPA_DATA_DmaBuf, SPA_TYPE_Int, SPA_TYPE_INFO_DATA_FD_BASE "DmaBuf", NULL },
        { SPA_DATA_MemId, SPA_TYPE_Int, SPA_TYPE_INFO_DATA_BASE "MemId", NULL },
        { 0, 0, NULL, NULL },
}

Referenced by spa_debug_buffer().

spa_type_meta_type

const struct spa_type_info spa_type_meta_type[]

Initial value:

= {
        { SPA_META_Invalid, SPA_TYPE_Pointer, SPA_TYPE_INFO_META_BASE "Invalid", NULL },
        { SPA_META_Header, SPA_TYPE_Pointer, SPA_TYPE_INFO_META_BASE "Header", NULL },
        { SPA_META_VideoCrop, SPA_TYPE_Pointer, SPA_TYPE_INFO_META_REGION_BASE "VideoCrop", NULL },
        { SPA_META_VideoDamage, SPA_TYPE_Pointer, SPA_TYPE_INFO_META_ARRAY_REGION_BASE "VideoDamage", NULL },
        { SPA_META_Bitmap, SPA_TYPE_Pointer, SPA_TYPE_INFO_META_BASE "Bitmap", NULL },
        { SPA_META_Cursor, SPA_TYPE_Pointer, SPA_TYPE_INFO_META_BASE "Cursor", NULL },
        { SPA_META_Control, SPA_TYPE_Pointer, SPA_TYPE_INFO_META_BASE "Control", NULL },
        { SPA_META_Busy, SPA_TYPE_Pointer, SPA_TYPE_INFO_META_BASE "Busy", NULL },
        { 0, 0, NULL, NULL },
}

Referenced by spa_debug_buffer().