src/calf/lv2_atom.h

   1 /*
   2   Copyright 2008-2012 David Robillard <http://drobilla.net>
   3
   4   Permission to use, copy, modify, and/or distribute this software for any
   5   purpose with or without fee is hereby granted, provided that the above
   6   copyright notice and this permission notice appear in all copies.
   7
   8   THIS SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
   9   WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
  10   MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
  11   ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
  12   WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
  13   ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
  14   OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
  15 */
  16
  17 /**
  18    @file atom.h C header for the LV2 Atom extension
  19    <http://lv2plug.in/ns/ext/atom>.
  20 */
  21
  22 #ifndef LV2_ATOM_H
  23 #define LV2_ATOM_H
  24
  25 #include <stdint.h>
  26 #include <stddef.h>
  27
  28 #define LV2_ATOM_URI    "http://lv2plug.in/ns/ext/atom"
  29 #define LV2_ATOM_PREFIX LV2_ATOM_URI "#"
  30
  31 #define LV2_ATOM__Atom          LV2_ATOM_PREFIX "Atom"
  32 #define LV2_ATOM__AtomPort      LV2_ATOM_PREFIX "AtomPort"
  33 #define LV2_ATOM__Blank         LV2_ATOM_PREFIX "Blank"
  34 #define LV2_ATOM__Bool          LV2_ATOM_PREFIX "Bool"
  35 #define LV2_ATOM__Chunk         LV2_ATOM_PREFIX "Chunk"
  36 #define LV2_ATOM__Double        LV2_ATOM_PREFIX "Double"
  37 #define LV2_ATOM__Event         LV2_ATOM_PREFIX "Event"
  38 #define LV2_ATOM__Float         LV2_ATOM_PREFIX "Float"
  39 #define LV2_ATOM__Int           LV2_ATOM_PREFIX "Int"
  40 #define LV2_ATOM__Literal       LV2_ATOM_PREFIX "Literal"
  41 #define LV2_ATOM__Long          LV2_ATOM_PREFIX "Long"
  42 #define LV2_ATOM__Number        LV2_ATOM_PREFIX "Number"
  43 #define LV2_ATOM__Object        LV2_ATOM_PREFIX "Object"
  44 #define LV2_ATOM__Path          LV2_ATOM_PREFIX "Path"
  45 #define LV2_ATOM__Property      LV2_ATOM_PREFIX "Property"
  46 #define LV2_ATOM__Resource      LV2_ATOM_PREFIX "Resource"
  47 #define LV2_ATOM__Sequence      LV2_ATOM_PREFIX "Sequence"
  48 #define LV2_ATOM__Sound         LV2_ATOM_PREFIX "Sound"
  49 #define LV2_ATOM__String        LV2_ATOM_PREFIX "String"
  50 #define LV2_ATOM__Tuple         LV2_ATOM_PREFIX "Tuple"
  51 #define LV2_ATOM__URI           LV2_ATOM_PREFIX "URI"
  52 #define LV2_ATOM__URID          LV2_ATOM_PREFIX "URID"
  53 #define LV2_ATOM__Vector        LV2_ATOM_PREFIX "Vector"
  54 #define LV2_ATOM__atomTransfer  LV2_ATOM_PREFIX "atomTransfer"
  55 #define LV2_ATOM__beatTime      LV2_ATOM_PREFIX "beatTime"
  56 #define LV2_ATOM__bufferType    LV2_ATOM_PREFIX "bufferType"
  57 #define LV2_ATOM__childType     LV2_ATOM_PREFIX "childType"
  58 #define LV2_ATOM__eventTransfer LV2_ATOM_PREFIX "eventTransfer"
  59 #define LV2_ATOM__frameTime     LV2_ATOM_PREFIX "frameTime"
  60 #define LV2_ATOM__supports      LV2_ATOM_PREFIX "supports"
  61 #define LV2_ATOM__timeUnit      LV2_ATOM_PREFIX "timeUnit"
  62
  63 #define LV2_ATOM_REFERENCE_TYPE 0
  64
  65 #ifdef __cplusplus
  66 extern "C" {
  67 #endif
  68
  69 /** This expression will fail to compile if double does not fit in 64 bits. */
  70 typedef char lv2_atom_assert_double_fits_in_64_bits[
  71         ((sizeof(double) <= sizeof(uint64_t)) * 2) - 1];
  72
  73 /**
  74    Return a pointer to the contents of an Atom.  The "contents" of an atom
  75    is the data past the complete type-specific header.
  76    @param type The type of the atom, e.g. LV2_Atom_String.
  77    @param atom A variable-sized atom.
  78 */
  79 #define LV2_ATOM_CONTENTS(type, atom) \
  80         ((void*)((uint8_t*)(atom) + sizeof(type)))
  81
  82 /**
  83    Const version of LV2_ATOM_CONTENTS.
  84 */
  85 #define LV2_ATOM_CONTENTS_CONST(type, atom) \
  86         ((const void*)((const uint8_t*)(atom) + sizeof(type)))
  87
  88 /**
  89    Return a pointer to the body of an Atom.  The "body" of an atom is the
  90    data just past the LV2_Atom head (i.e. the same offset for all types).
  91 */
  92 #define LV2_ATOM_BODY(atom) LV2_ATOM_CONTENTS(LV2_Atom, atom)
  93
  94 /**
  95    Const version of LV2_ATOM_BODY.
  96 */
  97 #define LV2_ATOM_BODY_CONST(atom) LV2_ATOM_CONTENTS_CONST(LV2_Atom, atom)
  98
  99 /** The header of an atom:Atom. */
 100 typedef struct {
 101         uint32_t size;  /**< Size in bytes, not including type and size. */
 102         uint32_t type;  /**< Type of this atom (mapped URI). */
 103 } LV2_Atom;
 104
 105 /** An atom:Int or atom:Bool.  May be cast to LV2_Atom. */
 106 typedef struct {
 107         LV2_Atom atom;  /**< Atom header. */
 108         int32_t  body;  /**< Integer value. */
 109 } LV2_Atom_Int;
 110
 111 /** An atom:Long.  May be cast to LV2_Atom. */
 112 typedef struct {
 113         LV2_Atom atom;  /**< Atom header. */
 114         int64_t  body;  /**< Integer value. */
 115 } LV2_Atom_Long;
 116
 117 /** An atom:Float.  May be cast to LV2_Atom. */
 118 typedef struct {
 119         LV2_Atom atom;  /**< Atom header. */
 120         float    body;  /**< Floating point value. */
 121 } LV2_Atom_Float;
 122
 123 /** An atom:Double.  May be cast to LV2_Atom. */
 124 typedef struct {
 125         LV2_Atom atom;  /**< Atom header. */
 126         double   body;  /**< Floating point value. */
 127 } LV2_Atom_Double;
 128
 129 /** An atom:Bool.  May be cast to LV2_Atom. */
 130 typedef LV2_Atom_Int LV2_Atom_Bool;
 131
 132 /** An atom:URID.  May be cast to LV2_Atom. */
 133 typedef struct {
 134         LV2_Atom atom;  /**< Atom header. */
 135         uint32_t body;  /**< URID. */
 136 } LV2_Atom_URID;
 137
 138 /** An atom:String.  May be cast to LV2_Atom. */
 139 typedef struct {
 140         LV2_Atom atom;  /**< Atom header. */
 141         /* Contents (a null-terminated UTF-8 string) follow here. */
 142 } LV2_Atom_String;
 143
 144 /** The body of an atom:Literal. */
 145 typedef struct {
 146         uint32_t datatype;  /**< Datatype URID. */
 147         uint32_t lang;      /**< Language URID. */
 148         /* Contents (a null-terminated UTF-8 string) follow here. */
 149 } LV2_Atom_Literal_Body;
 150
 151 /** An atom:Literal.  May be cast to LV2_Atom. */
 152 typedef struct {
 153         LV2_Atom              atom;  /**< Atom header. */
 154         LV2_Atom_Literal_Body body;  /**< Body. */
 155 } LV2_Atom_Literal;
 156
 157 /** An atom:Tuple.  May be cast to LV2_Atom. */
 158 typedef struct {
 159         LV2_Atom atom;  /**< Atom header. */
 160         /* Contents (a series of complete atoms) follow here. */
 161 } LV2_Atom_Tuple;
 162
 163 /** The body of an atom:Vector. */
 164 typedef struct {
 165         uint32_t child_size;  /**< The size of each element in the vector. */
 166         uint32_t child_type;  /**< The type of each element in the vector. */
 167         /* Contents (a series of packed atom bodies) follow here. */
 168 } LV2_Atom_Vector_Body;
 169
 170 /** An atom:Vector.  May be cast to LV2_Atom. */
 171 typedef struct {
 172         LV2_Atom             atom;  /**< Atom header. */
 173         LV2_Atom_Vector_Body body;  /**< Body. */
 174 } LV2_Atom_Vector;
 175
 176 /** The body of an atom:Property (e.g. in an atom:Object). */
 177 typedef struct {
 178         uint32_t key;      /**< Key (predicate) (mapped URI). */
 179         uint32_t context;  /**< Context URID (may be, and generally is, 0). */
 180         LV2_Atom value;    /**< Value atom header. */
 181         /* Value atom body follows here. */
 182 } LV2_Atom_Property_Body;
 183
 184 /** An atom:Property.  May be cast to LV2_Atom. */
 185 typedef struct {
 186         LV2_Atom               atom;  /**< Atom header. */
 187         LV2_Atom_Property_Body body;  /**< Body. */
 188 } LV2_Atom_Property;
 189
 190 /** The body of an atom:Object. May be cast to LV2_Atom. */
 191 typedef struct {
 192         uint32_t id;     /**< URID, or 0 for blank. */
 193         uint32_t otype;  /**< Type URID (same as rdf:type, for fast dispatch). */
 194         /* Contents (a series of property bodies) follow here. */
 195 } LV2_Atom_Object_Body;
 196
 197 /** An atom:Object.  May be cast to LV2_Atom. */
 198 typedef struct {
 199         LV2_Atom             atom;  /**< Atom header. */
 200         LV2_Atom_Object_Body body;  /**< Body. */
 201 } LV2_Atom_Object;
 202
 203 /** The header of an atom:Event.  Note this type is NOT an LV2_Atom. */
 204 typedef struct {
 205         /** Time stamp.  Which type is valid is determined by context. */
 206         union {
 207                 int64_t frames;  /**< Time in audio frames. */
 208                 double  beats;   /**< Time in beats. */
 209         } time;
 210         LV2_Atom body;  /**< Event body atom header. */
 211         /* Body atom contents follow here. */
 212 } LV2_Atom_Event;
 213
 214 /**
 215    The body of an atom:Sequence (a sequence of events).
 216
 217    The unit field is either a URID that described an appropriate time stamp
 218    type, or may be 0 where a default stamp type is known.  For
 219    LV2_Descriptor::run(), the default stamp type is audio frames.
 220
 221    The contents of a sequence is a series of LV2_Atom_Event, each aligned
 222    to 64-bits, e.g.:
 223    <pre>
 224    | Event 1 (size 6)                              | Event 2
 225    |       |       |       |       |       |       |       |       |
 226    | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | |
 227    |FRAMES |SUBFRMS|TYPE   |SIZE   |DATADATADATAPAD|FRAMES |SUBFRMS|...
 228    </pre>
 229 */
 230 typedef struct {
 231         uint32_t unit;  /**< URID of unit of event time stamps. */
 232         uint32_t pad;   /**< Currently unused. */
 233         /* Contents (a series of events) follow here. */
 234 } LV2_Atom_Sequence_Body;
 235
 236 /** An atom:Sequence. */
 237 typedef struct {
 238         LV2_Atom               atom;  /**< Atom header. */
 239         LV2_Atom_Sequence_Body body;  /**< Body. */
 240 } LV2_Atom_Sequence;
 241
 242 #ifdef __cplusplus
 243 }  /* extern "C" */
 244 #endif
 245
 246 #endif  /* LV2_ATOM_H */