diff options
Diffstat (limited to 'ext/atom.lv2/atom.h')
| -rw-r--r-- | ext/atom.lv2/atom.h | 138 |
1 files changed, 70 insertions, 68 deletions
diff --git a/ext/atom.lv2/atom.h b/ext/atom.lv2/atom.h index 61482c7..d617435 100644 --- a/ext/atom.lv2/atom.h +++ b/ext/atom.lv2/atom.h @@ -18,11 +18,8 @@ @file atom.h C header for the LV2 Atom extension <http://lv2plug.in/ns/ext/atom>. - This extension defines convenience structs that should match the definition - of the built-in types of the atom extension. The layout of atoms in this - header must match the description in RDF. The RDF description of an atom - type should be considered normative. This header is a non-normative (but - hopefully accurate) implementation of that specification. + This header describes the binary layout of various types defined in the + atom extension. */ #ifndef LV2_ATOM_H @@ -35,6 +32,10 @@ #include <stdint.h> #include <stddef.h> +#ifdef __cplusplus +extern "C" { +#endif + /** An LV2 Atom. @@ -45,70 +46,76 @@ (e.g. with memcpy) using the size field, except atoms with type 0. An atom with type 0 is a reference, and may only be used via the functions provided in LV2_Blob_Support (e.g. it MUST NOT be manually copied). - - Note that an LV2_Atom is the latter two fields of an LV2_Event as defined by - the <a href="http://lv2plug.in/ns/ext/event">LV2 events extension</a>. The - host MAY marshal an LV2_Event to an LV2_Atom by simply pointing to the - offset of <code>type</code>. The macro LV2_ATOM_FROM_EVENT is provided in - this header for this purpose. */ typedef struct { - - /** - The type of this atom. - - This number is mapped from a URI using the extension - <http://lv2plug.in/ns/ext/uri-map> with 'map' = - "http://lv2plug.in/ns/ext/atom". Type 0 is a special case which - indicates this atom is a reference and MUST NOT be copied manually. - */ - uint16_t type; - - /** - The size of this atom, not including this header, in bytes. - */ - uint16_t size; - - /** - Size bytes of data follow here. - */ - uint8_t body[]; - + uint32_t type; /**< Type of this atom (mapped URI). */ + uint32_t size; /**< Size in bytes, not including type and size. */ + uint8_t body[]; /**< Body of length @ref size bytes. */ } LV2_Atom; /** - The body of an atom:Literal. + An atom:String. + This type may safely be cast to LV2_Atom. */ typedef struct { - uint32_t datatype; /**< The ID of the datatype of this literal */ - uint32_t lang; /**< The ID of the language of this literal */ - uint8_t str[]; /**< Null-terminated string data in UTF-8 encoding */ + uint32_t type; /**< Type of this atom (mapped URI). */ + uint32_t size; /**< Size in bytes, not including type and size. */ + uint8_t str[]; /**< Null-terminated string data in UTF-8 encoding. */ +} LV2_Atom_String; + +/** + An atom:Literal. + This type may safely be cast to LV2_Atom. +*/ +typedef struct { + uint32_t type; /**< Type of this atom (mapped URI). */ + uint32_t size; /**< Size in bytes, not including type and size. */ + uint32_t datatype; /**< The ID of the datatype of this literal. */ + uint32_t lang; /**< The ID of the language of this literal. */ + uint8_t str[]; /**< Null-terminated string data in UTF-8 encoding. */ } LV2_Atom_Literal; /** - The body of an atom:Vector. + An atom:ID. + This type may safely be cast to LV2_Atom. */ typedef struct { - uint16_t elem_count; /**< The number of elements in the vector */ - uint16_t elem_type; /**< The type of each element in the vector */ - uint8_t elems[]; /**< Sequence of element bodies */ + uint32_t type; /**< Type of this atom (mapped URI). */ + uint32_t size; /**< Size in bytes, not including type and size. */ + uint32_t id; /**< Value, a URI mapped to an integer. */ +} LV2_Atom_ID; + +/** + An atom:Vector. + This type may safely be cast to LV2_Atom. +*/ +typedef struct { + uint32_t type; /**< Type of this atom (mapped URI). */ + uint32_t size; /**< Size in bytes, not including type and size. */ + uint32_t elem_count; /**< The number of elements in the vector */ + uint32_t elem_type; /**< The type of each element in the vector */ + uint8_t elems[]; /**< Sequence of element bodies */ } LV2_Atom_Vector; /** The body of an atom:Property. + Note this type is not an LV2_Atom. */ typedef struct _LV2_Atom_Property { - uint32_t key; /**< ID of key (predicate) */ - LV2_Atom value; /**< Value (object) */ + uint32_t key; /**< Key (predicate) (mapped URI). */ + LV2_Atom value; /**< Value (object) */ } LV2_Atom_Property; /** - The body of an atom:Resource or atom:Blank. + An atom:Object (atom:Resource or atom:Blank). + This type may safely be cast to LV2_Atom. */ typedef struct { - uint32_t context; /**< ID of context graph, or 0 for default */ - uint32_t id; /**< URID (for Resource) or blank ID (for Blank) */ - uint8_t properties[]; /**< Sequence of LV2_Atom_Property */ + uint32_t type; /**< Type of this atom (mapped URI). */ + uint32_t size; /**< Size in bytes, not including type and size. */ + uint32_t context; /**< ID of context graph, or 0 for default */ + uint32_t id; /**< URID (for Resource) or blank ID (for Blank) */ + uint8_t properties[]; /**< Sequence of LV2_Atom_Property */ } LV2_Object; /** @@ -121,27 +128,9 @@ typedef struct { the @ref body field of the Event. */ typedef struct { - - /** - The frames portion of timestamp. The unit of this value may depend on - context, but for events processed by LV2_Descriptor::run() the unit is - audio frames relative to this block (e.g. frame 0 is the first frame in - this call to run()) - */ - uint32_t frames; - - /** - The sub-frames portion of timestamp. The unit of this value may depend - on context, but for events processed by LV2_Descriptor::run() the unit - is 1/(2^32) of an audio frame. - */ - uint32_t subframes; - - /** - The body of this event. - */ - LV2_Atom body; - + uint32_t frames; /**< Time in frames relative to this block. */ + uint32_t subframes; /**< Fractional time in 1/(2^32)ths of a frame. */ + LV2_Atom body; /**< Event body. */ } LV2_Atom_Event; /** @@ -208,4 +197,17 @@ typedef struct { } LV2_Atom_Buffer; -#endif /* LV2_ATOM_H */ +/** + Pad a size to 64 bits. +*/ +static inline uint32_t +lv2_atom_pad_size(uint32_t size) +{ + return (size + 7) & (~7); +} + +#ifdef __cplusplus +} /* extern "C" */ +#endif + +#endif /* LV2_ATOM_H */ |