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/* Simple Plugin API */
/* SPDX-FileCopyrightText: Copyright © 2018 Wim Taymans */
/* SPDX-License-Identifier: MIT */
#ifndef SPA_BUFFER_H
#define SPA_BUFFER_H
#ifdef __cplusplus
extern "C" {
#endif
#include <spa/utils/defs.h>
#include <spa/buffer/meta.h>
#ifndef SPA_API_BUFFER
#ifdef SPA_API_IMPL
#define SPA_API_BUFFER SPA_API_IMPL
#else
#define SPA_API_BUFFER static inline
#endif
#endif
/** \defgroup spa_buffer Buffers
*
* Buffers describe the data and metadata that is exchanged between
* ports of a node.
*/
/**
* \addtogroup spa_buffer
* \{
*/
enum spa_data_type {
SPA_DATA_Invalid,
SPA_DATA_MemPtr, /**< pointer to memory, the data field in
* struct spa_data is set. */
SPA_DATA_MemFd, /**< memfd, mmap to get to memory. */
SPA_DATA_DmaBuf, /**< fd to dmabuf memory. This might not be readily
* mappable (unless the MAPPABLE flag is set) and should
* normally be handled with DMABUF apis. */
SPA_DATA_MemId, /**< memory is identified with an id. The actual memory
* can be obtained in some other way and can be identified
* with this id. */
SPA_DATA_SyncObj, /**< a syncobj, usually requires a spa_meta_sync_timeline metadata
* with timeline points. */
_SPA_DATA_LAST, /**< not part of ABI */
};
/** Chunk of memory, can change for each buffer */
struct spa_chunk {
uint32_t offset; /**< offset of valid data. Should be taken
* modulo the data maxsize to get the offset
* in the data memory. */
uint32_t size; /**< size of valid data. Should be clamped to
* maxsize. */
int32_t stride; /**< stride of valid data */
#define SPA_CHUNK_FLAG_NONE 0
#define SPA_CHUNK_FLAG_CORRUPTED (1u<<0) /**< chunk data is corrupted in some way */
#define SPA_CHUNK_FLAG_EMPTY (1u<<1) /**< chunk data is empty with media specific
* neutral data such as silence or black. This
* could be used to optimize processing. */
int32_t flags; /**< chunk flags */
};
/** Data for a buffer this stays constant for a buffer */
struct spa_data {
uint32_t type; /**< memory type, one of enum spa_data_type, when
* allocating memory, the type contains a bitmask
* of allowed types. SPA_ID_INVALID is a special
* value for the allocator to indicate that the
* other side did not explicitly specify any
* supported data types. It should probably use
* a memory type that does not require special
* handling in addition to simple mmap/munmap. */
#define SPA_DATA_FLAG_NONE 0
#define SPA_DATA_FLAG_READABLE (1u<<0) /**< data is readable */
#define SPA_DATA_FLAG_WRITABLE (1u<<1) /**< data is writable */
#define SPA_DATA_FLAG_DYNAMIC (1u<<2) /**< data pointer can be changed */
#define SPA_DATA_FLAG_READWRITE (SPA_DATA_FLAG_READABLE|SPA_DATA_FLAG_WRITABLE)
#define SPA_DATA_FLAG_MAPPABLE (1u<<3) /**< data is mappable with simple mmap/munmap. Some memory
* types are not simply mappable (DmaBuf) unless explicitly
* specified with this flag. */
uint32_t flags; /**< data flags */
int64_t fd; /**< optional fd for data */
uint32_t mapoffset; /**< offset to map fd at, this is page aligned */
uint32_t maxsize; /**< max size of data */
void *data; /**< optional data pointer */
struct spa_chunk *chunk; /**< valid chunk of memory */
};
/** A Buffer */
struct spa_buffer {
uint32_t n_metas; /**< number of metadata */
uint32_t n_datas; /**< number of data members */
struct spa_meta *metas; /**< array of metadata */
struct spa_data *datas; /**< array of data members */
};
/** Find metadata in a buffer */
SPA_API_BUFFER struct spa_meta *spa_buffer_find_meta(const struct spa_buffer *b, uint32_t type)
{
uint32_t i;
for (i = 0; i < b->n_metas; i++)
if (b->metas[i].type == type)
return &b->metas[i];
return NULL;
}
SPA_API_BUFFER void *spa_buffer_find_meta_data(const struct spa_buffer *b, uint32_t type, size_t size)
{
struct spa_meta *m;
if ((m = spa_buffer_find_meta(b, type)) && m->size >= size)
return m->data;
return NULL;
}
/**
* \}
*/
#ifdef __cplusplus
} /* extern "C" */
#endif
#endif /* SPA_BUFFER_H */