diff options
Diffstat (limited to 'lv2/core/lv2.h')
| -rw-r--r-- | lv2/core/lv2.h | 452 |
1 files changed, 224 insertions, 228 deletions
diff --git a/lv2/core/lv2.h b/lv2/core/lv2.h index c0376e9..82bc7ab 100644 --- a/lv2/core/lv2.h +++ b/lv2/core/lv2.h @@ -144,7 +144,7 @@ extern "C" { compare to NULL (or 0 for C++) but otherwise the host MUST NOT attempt to interpret it. */ -typedef void * LV2_Handle; +typedef void* LV2_Handle; /** Feature. @@ -155,20 +155,20 @@ typedef void * LV2_Handle; Some features, such as lv2:isLive, do not require the host to pass data. */ typedef struct { - /** - A globally unique, case-sensitive identifier (URI) for this feature. + /** + A globally unique, case-sensitive identifier (URI) for this feature. - This MUST be a valid URI string as defined by RFC 3986. - */ - const char * URI; + This MUST be a valid URI string as defined by RFC 3986. + */ + const char* URI; - /** - Pointer to arbitrary data. + /** + Pointer to arbitrary data. - The format of this data is defined by the extension which describes the - feature with the given `URI`. - */ - void * data; + The format of this data is defined by the extension which describes the + feature with the given `URI`. + */ + void* data; } LV2_Feature; /** @@ -178,190 +178,187 @@ typedef struct { a plugin. */ typedef struct LV2_Descriptor { - /** - A globally unique, case-sensitive identifier for this plugin. - - This MUST be a valid URI string as defined by RFC 3986. All plugins with - the same URI MUST be compatible to some degree, see - http://lv2plug.in/ns/lv2core for details. - */ - const char * URI; - - /** - Instantiate the plugin. - - Note that instance initialisation should generally occur in activate() - rather than here. If a host calls instantiate(), it MUST call cleanup() - at some point in the future. - - @param descriptor Descriptor of the plugin to instantiate. - - @param sample_rate Sample rate, in Hz, for the new plugin instance. - - @param bundle_path Path to the LV2 bundle which contains this plugin - binary. It MUST include the trailing directory separator so that simply - appending a filename will yield the path to that file in the bundle. - - @param features A NULL terminated array of LV2_Feature structs which - represent the features the host supports. Plugins may refuse to - instantiate if required features are not found here. However, hosts MUST - NOT use this as a discovery mechanism: instead, use the RDF data to - determine which features are required and do not attempt to instantiate - unsupported plugins at all. This parameter MUST NOT be NULL, i.e. a host - that supports no features MUST pass a single element array containing - NULL. - - @return A handle for the new plugin instance, or NULL if instantiation - has failed. - */ - LV2_Handle (*instantiate)(const struct LV2_Descriptor * descriptor, - double sample_rate, - const char * bundle_path, - const LV2_Feature *const * features); - - /** - Connect a port on a plugin instance to a memory location. - - Plugin writers should be aware that the host may elect to use the same - buffer for more than one port and even use the same buffer for both - input and output (see lv2:inPlaceBroken in lv2.ttl). - - If the plugin has the feature lv2:hardRTCapable then there are various - things that the plugin MUST NOT do within the connect_port() function; - see lv2core.ttl for details. - - connect_port() MUST be called at least once for each port before run() - is called, unless that port is lv2:connectionOptional. The plugin must - pay careful attention to the block size passed to run() since the block - allocated may only just be large enough to contain the data, and is not - guaranteed to remain constant between run() calls. - - connect_port() may be called more than once for a plugin instance to - allow the host to change the buffers that the plugin is reading or - writing. These calls may be made before or after activate() or - deactivate() calls. - - @param instance Plugin instance containing the port. - - @param port Index of the port to connect. The host MUST NOT try to - connect a port index that is not defined in the plugin's RDF data. If - it does, the plugin's behaviour is undefined (a crash is likely). - - @param data_location Pointer to data of the type defined by the port - type in the plugin's RDF data (for example, an array of float for an - lv2:AudioPort). This pointer must be stored by the plugin instance and - used to read/write data when run() is called. Data present at the time - of the connect_port() call MUST NOT be considered meaningful. - */ - void (*connect_port)(LV2_Handle instance, - uint32_t port, - void * data_location); - - /** - Initialise a plugin instance and activate it for use. - - This is separated from instantiate() to aid real-time support and so - that hosts can reinitialise a plugin instance by calling deactivate() - and then activate(). In this case the plugin instance MUST reset all - state information dependent on the history of the plugin instance except - for any data locations provided by connect_port(). If there is nothing - for activate() to do then this field may be NULL. - - When present, hosts MUST call this function once before run() is called - for the first time. This call SHOULD be made as close to the run() call - as possible and indicates to real-time plugins that they are now live, - however plugins MUST NOT rely on a prompt call to run() after - activate(). - - The host MUST NOT call activate() again until deactivate() has been - called first. If a host calls activate(), it MUST call deactivate() at - some point in the future. Note that connect_port() may be called before - or after activate(). - */ - void (*activate)(LV2_Handle instance); - - /** - Run a plugin instance for a block. - - Note that if an activate() function exists then it must be called before - run(). If deactivate() is called for a plugin instance then run() may - not be called until activate() has been called again. - - If the plugin has the feature lv2:hardRTCapable then there are various - things that the plugin MUST NOT do within the run() function (see - lv2core.ttl for details). - - As a special case, when `sample_count` is 0, the plugin should update - any output ports that represent a single instant in time (for example, - control ports, but not audio ports). This is particularly useful for - latent plugins, which should update their latency output port so hosts - can pre-roll plugins to compute latency. Plugins MUST NOT crash when - `sample_count` is 0. - - @param instance Instance to be run. - - @param sample_count The block size (in samples) for which the plugin - instance must run. - */ - void (*run)(LV2_Handle instance, - uint32_t sample_count); - - /** - Deactivate a plugin instance (counterpart to activate()). - - Hosts MUST deactivate all activated instances after they have been run() - for the last time. This call SHOULD be made as close to the last run() - call as possible and indicates to real-time plugins that they are no - longer live, however plugins MUST NOT rely on prompt deactivation. If - there is nothing for deactivate() to do then this field may be NULL - - Deactivation is not similar to pausing since the plugin instance will be - reinitialised by activate(). However, deactivate() itself MUST NOT fully - reset plugin state. For example, the host may deactivate a plugin, then - store its state (using some extension to do so). - - Hosts MUST NOT call deactivate() unless activate() was previously - called. Note that connect_port() may be called before or after - deactivate(). - */ - void (*deactivate)(LV2_Handle instance); - - /** - Clean up a plugin instance (counterpart to instantiate()). - - Once an instance of a plugin has been finished with it must be deleted - using this function. The instance handle passed ceases to be valid after - this call. - - If activate() was called for a plugin instance then a corresponding call - to deactivate() MUST be made before cleanup() is called. Hosts MUST NOT - call cleanup() unless instantiate() was previously called. - */ - void (*cleanup)(LV2_Handle instance); - - /** - Return additional plugin data defined by some extenion. - - A typical use of this facility is to return a struct containing function - pointers to extend the LV2_Descriptor API. - - The actual type and meaning of the returned object MUST be specified - precisely by the extension. This function MUST return NULL for any - unsupported URI. If a plugin does not support any extension data, this - field may be NULL. - - The host is never responsible for freeing the returned value. - */ - const void * (*extension_data)(const char * uri); + /** + A globally unique, case-sensitive identifier for this plugin. + + This MUST be a valid URI string as defined by RFC 3986. All plugins with + the same URI MUST be compatible to some degree, see + http://lv2plug.in/ns/lv2core for details. + */ + const char* URI; + + /** + Instantiate the plugin. + + Note that instance initialisation should generally occur in activate() + rather than here. If a host calls instantiate(), it MUST call cleanup() + at some point in the future. + + @param descriptor Descriptor of the plugin to instantiate. + + @param sample_rate Sample rate, in Hz, for the new plugin instance. + + @param bundle_path Path to the LV2 bundle which contains this plugin + binary. It MUST include the trailing directory separator so that simply + appending a filename will yield the path to that file in the bundle. + + @param features A NULL terminated array of LV2_Feature structs which + represent the features the host supports. Plugins may refuse to + instantiate if required features are not found here. However, hosts MUST + NOT use this as a discovery mechanism: instead, use the RDF data to + determine which features are required and do not attempt to instantiate + unsupported plugins at all. This parameter MUST NOT be NULL, i.e. a host + that supports no features MUST pass a single element array containing + NULL. + + @return A handle for the new plugin instance, or NULL if instantiation + has failed. + */ + LV2_Handle (*instantiate)(const struct LV2_Descriptor* descriptor, + double sample_rate, + const char* bundle_path, + const LV2_Feature* const* features); + + /** + Connect a port on a plugin instance to a memory location. + + Plugin writers should be aware that the host may elect to use the same + buffer for more than one port and even use the same buffer for both + input and output (see lv2:inPlaceBroken in lv2.ttl). + + If the plugin has the feature lv2:hardRTCapable then there are various + things that the plugin MUST NOT do within the connect_port() function; + see lv2core.ttl for details. + + connect_port() MUST be called at least once for each port before run() + is called, unless that port is lv2:connectionOptional. The plugin must + pay careful attention to the block size passed to run() since the block + allocated may only just be large enough to contain the data, and is not + guaranteed to remain constant between run() calls. + + connect_port() may be called more than once for a plugin instance to + allow the host to change the buffers that the plugin is reading or + writing. These calls may be made before or after activate() or + deactivate() calls. + + @param instance Plugin instance containing the port. + + @param port Index of the port to connect. The host MUST NOT try to + connect a port index that is not defined in the plugin's RDF data. If + it does, the plugin's behaviour is undefined (a crash is likely). + + @param data_location Pointer to data of the type defined by the port + type in the plugin's RDF data (for example, an array of float for an + lv2:AudioPort). This pointer must be stored by the plugin instance and + used to read/write data when run() is called. Data present at the time + of the connect_port() call MUST NOT be considered meaningful. + */ + void (*connect_port)(LV2_Handle instance, uint32_t port, void* data_location); + + /** + Initialise a plugin instance and activate it for use. + + This is separated from instantiate() to aid real-time support and so + that hosts can reinitialise a plugin instance by calling deactivate() + and then activate(). In this case the plugin instance MUST reset all + state information dependent on the history of the plugin instance except + for any data locations provided by connect_port(). If there is nothing + for activate() to do then this field may be NULL. + + When present, hosts MUST call this function once before run() is called + for the first time. This call SHOULD be made as close to the run() call + as possible and indicates to real-time plugins that they are now live, + however plugins MUST NOT rely on a prompt call to run() after + activate(). + + The host MUST NOT call activate() again until deactivate() has been + called first. If a host calls activate(), it MUST call deactivate() at + some point in the future. Note that connect_port() may be called before + or after activate(). + */ + void (*activate)(LV2_Handle instance); + + /** + Run a plugin instance for a block. + + Note that if an activate() function exists then it must be called before + run(). If deactivate() is called for a plugin instance then run() may + not be called until activate() has been called again. + + If the plugin has the feature lv2:hardRTCapable then there are various + things that the plugin MUST NOT do within the run() function (see + lv2core.ttl for details). + + As a special case, when `sample_count` is 0, the plugin should update + any output ports that represent a single instant in time (for example, + control ports, but not audio ports). This is particularly useful for + latent plugins, which should update their latency output port so hosts + can pre-roll plugins to compute latency. Plugins MUST NOT crash when + `sample_count` is 0. + + @param instance Instance to be run. + + @param sample_count The block size (in samples) for which the plugin + instance must run. + */ + void (*run)(LV2_Handle instance, uint32_t sample_count); + + /** + Deactivate a plugin instance (counterpart to activate()). + + Hosts MUST deactivate all activated instances after they have been run() + for the last time. This call SHOULD be made as close to the last run() + call as possible and indicates to real-time plugins that they are no + longer live, however plugins MUST NOT rely on prompt deactivation. If + there is nothing for deactivate() to do then this field may be NULL + + Deactivation is not similar to pausing since the plugin instance will be + reinitialised by activate(). However, deactivate() itself MUST NOT fully + reset plugin state. For example, the host may deactivate a plugin, then + store its state (using some extension to do so). + + Hosts MUST NOT call deactivate() unless activate() was previously + called. Note that connect_port() may be called before or after + deactivate(). + */ + void (*deactivate)(LV2_Handle instance); + + /** + Clean up a plugin instance (counterpart to instantiate()). + + Once an instance of a plugin has been finished with it must be deleted + using this function. The instance handle passed ceases to be valid after + this call. + + If activate() was called for a plugin instance then a corresponding call + to deactivate() MUST be made before cleanup() is called. Hosts MUST NOT + call cleanup() unless instantiate() was previously called. + */ + void (*cleanup)(LV2_Handle instance); + + /** + Return additional plugin data defined by some extenion. + + A typical use of this facility is to return a struct containing function + pointers to extend the LV2_Descriptor API. + + The actual type and meaning of the returned object MUST be specified + precisely by the extension. This function MUST return NULL for any + unsupported URI. If a plugin does not support any extension data, this + field may be NULL. + + The host is never responsible for freeing the returned value. + */ + const void* (*extension_data)(const char* uri); } LV2_Descriptor; /** Helper macro needed for LV2_SYMBOL_EXPORT when using C++. */ #ifdef __cplusplus -# define LV2_SYMBOL_EXTERN extern "C" +# define LV2_SYMBOL_EXTERN extern "C" #else -# define LV2_SYMBOL_EXTERN +# define LV2_SYMBOL_EXTERN #endif /** @@ -369,9 +366,10 @@ typedef struct LV2_Descriptor { by the host as a symbol from the dynamic library. */ #ifdef _WIN32 -# define LV2_SYMBOL_EXPORT LV2_SYMBOL_EXTERN __declspec(dllexport) +# define LV2_SYMBOL_EXPORT LV2_SYMBOL_EXTERN __declspec(dllexport) #else -# define LV2_SYMBOL_EXPORT LV2_SYMBOL_EXTERN __attribute__((visibility("default"))) +# define LV2_SYMBOL_EXPORT \ + LV2_SYMBOL_EXTERN __attribute__((visibility("default"))) #endif /** @@ -398,13 +396,13 @@ typedef struct LV2_Descriptor { consistent between loads of the plugin library. */ LV2_SYMBOL_EXPORT -const LV2_Descriptor * lv2_descriptor(uint32_t index); +const LV2_Descriptor* +lv2_descriptor(uint32_t index); /** Type of the lv2_descriptor() function in a library (old discovery API). */ -typedef const LV2_Descriptor * -(*LV2_Descriptor_Function)(uint32_t index); +typedef const LV2_Descriptor* (*LV2_Descriptor_Function)(uint32_t index); /** Handle for a library descriptor. @@ -418,34 +416,33 @@ typedef void* LV2_Lib_Handle; lv2_lib_descriptor() function in the shared object. */ typedef struct { - /** - Opaque library data which must be passed as the first parameter to all - the methods of this struct. - */ - LV2_Lib_Handle handle; - - /** - The total size of this struct. This allows for this struct to be - expanded in the future if necessary. This MUST be set by the library to - sizeof(LV2_Lib_Descriptor). The host MUST NOT access any fields of this - struct beyond get_plugin() unless this field indicates they are present. - */ - uint32_t size; - - /** - Destroy this library descriptor and free all related resources. - */ - void (*cleanup)(LV2_Lib_Handle handle); - - /** - Plugin accessor. - - Plugins are accessed by index using values from 0 upwards. Out of range - indices MUST result in this function returning NULL, so the host can - enumerate plugins by increasing `index` until NULL is returned. - */ - const LV2_Descriptor * (*get_plugin)(LV2_Lib_Handle handle, - uint32_t index); + /** + Opaque library data which must be passed as the first parameter to all + the methods of this struct. + */ + LV2_Lib_Handle handle; + + /** + The total size of this struct. This allows for this struct to be + expanded in the future if necessary. This MUST be set by the library to + sizeof(LV2_Lib_Descriptor). The host MUST NOT access any fields of this + struct beyond get_plugin() unless this field indicates they are present. + */ + uint32_t size; + + /** + Destroy this library descriptor and free all related resources. + */ + void (*cleanup)(LV2_Lib_Handle handle); + + /** + Plugin accessor. + + Plugins are accessed by index using values from 0 upwards. Out of range + indices MUST result in this function returning NULL, so the host can + enumerate plugins by increasing `index` until NULL is returned. + */ + const LV2_Descriptor* (*get_plugin)(LV2_Lib_Handle handle, uint32_t index); } LV2_Lib_Descriptor; /** @@ -465,16 +462,15 @@ typedef struct { from that library have been destroyed. */ LV2_SYMBOL_EXPORT -const LV2_Lib_Descriptor * -lv2_lib_descriptor(const char * bundle_path, - const LV2_Feature *const * features); +const LV2_Lib_Descriptor* +lv2_lib_descriptor(const char* bundle_path, const LV2_Feature* const* features); /** Type of the lv2_lib_descriptor() function in an LV2 library. */ -typedef const LV2_Lib_Descriptor * -(*LV2_Lib_Descriptor_Function)(const char * bundle_path, - const LV2_Feature *const * features); +typedef const LV2_Lib_Descriptor* (*LV2_Lib_Descriptor_Function)( + const char* bundle_path, + const LV2_Feature* const* features); #ifdef __cplusplus } /* extern "C" */ |