diff options
Diffstat (limited to 'ext/dynmanifest.lv2/dynmanifest.h')
| -rw-r--r-- | ext/dynmanifest.lv2/dynmanifest.h | 186 |
1 files changed, 80 insertions, 106 deletions
diff --git a/ext/dynmanifest.lv2/dynmanifest.h b/ext/dynmanifest.lv2/dynmanifest.h index 204e18b..5594293 100644 --- a/ext/dynmanifest.lv2/dynmanifest.h +++ b/ext/dynmanifest.lv2/dynmanifest.h @@ -31,7 +31,8 @@ #define LV2_DYN_MANIFEST_H_INCLUDED #include <stdio.h> -#include "lv2.h" + +#include "lv2/lv2plug.in/ns/lv2core/lv2.h" #define LV2_DYN_MANIFEST_URI "http://lv2plug.in/ns/ext/dynmanifest" @@ -68,46 +69,45 @@ extern "C" { * * This API is extensible in a similar fashion as the LV2 API. * + * == Accessing data == + * + * Whenever a host wants to access data using this API, it could: + * + * -# Call lv2_dyn_manifest_open(); + * -# Create an empty resource identified by a FILE *; + * -# Get a "list" of exposed subject URIs using + * lv2_dyn_manifest_get_subjects(); + * -# Call lv2_dyn_manifest_get_data() for each URI of interest, in order to + * get data related to that URI (either by calling the function subsequently + * with the same FILE * resource, or by creating more FILE * resources to + * perform parallel calls); + * -# Call lv2_dyn_manifest_close(); + * -# Parse the content of the FILE * resource(s). + * -# Free/delete/unlink the FILE * resource(s). + * + * The content of the FILE * resources has to be interpreted by the host as a + * regular file in Turtle syntax. This also means that each FILE * resource + * should also contain needed prefix definitions, in case any are used. + * + * Each call to lv2_dyn_manifest_open() automatically implies the (re)generation + * of the dynamic manifest on the library side. + * + * When such calls are made, data fetched from the involved library using this + * API before such call is to be considered no more valid. + * + * In case the plugin library uses this same API to access other dynamic + * manifests, it MUST implement some mechanism to avoid potentially endless + * loops (such as A loads B, B loads A, etc.) and, in case such a loop is + * detected, the operation MUST fail. For this purpose, use of a static boolean + * flag is suggested. + * * == Threading rules == * - * This specification defines threading rule classes, similarly to the LV2 - * specification. - * - * The functions defined by this API belong to: - * - * - Dynamic manifest open class: lv2_dyn_manifest_open() - * - Dynamic manifest close class: lv2_dyn_manifest_close() - * - Dynamic manifest file class: lv2_dyn_manifest_get_subjects(), - * lv2_dyn_manifest_get_data() - * - * The rules that hosts must follow are these: - * - * - When a function from the Dynamic manifest open or the Dynamic manifest - * close class is running, no other functions in the same shared object file - * may run. - * - When a function from the Dynamic manifest file class is called, no other - * functions from the same class may run if they are given at least one - * FILE * argument with the same value. - * - A function from the Dynamic manifest open class may not run after a - * successful call to a function from the same class, in case a function from - * the Dynamic manifest close class was not successfully called in the - * meanwhile. - * - A function from the Dynamic manifest close class may only run after a - * successful call to a function from the Dynamic manifest open class. - * - A function from the Dynamic manifest file class may only run beetween a - * successful call to a function from the Dynamic manifest open class and the - * following successful call to a function from the Dynamic manifest close - * class. + * All of the functions defined by this specification belong to the Discovery + * class. * * Extensions to this specification which add new functions MUST declare in - * which of these classes the functions belong, or define new classes for them; - * furthermore, classes defined by such extensions MUST only allow calls after - * a successful call to a function from the Dynamic manifest open class and - * before the following successful call to a function from the Dynamic manifest - * close class. - * - * Any simultaneous calls that are not explicitly forbidden by these rules are - * allowed. + * which classes the functions belong, or define new classes for them. */ @@ -118,7 +118,7 @@ extern "C" { * * This handle indicates a particular status of a dynamic manifest generator. * The host MUST NOT attempt to interpret it and, unlikely LV2_Handle, it is NOT - * even valid to compare this to NULL. The dynamic manifest generator may use it + * even valid to compare this to NULL. The dynamic manifest generator MAY use it * to reference internal data. */ typedef void * LV2_Dyn_Manifest_Handle; @@ -126,44 +126,11 @@ typedef void * LV2_Dyn_Manifest_Handle; /* ************************************************************************* */ -/** Accessing data. - * - * Whenever a host wants to access data using this API, it could: - * - * 1. Call lv2_dyn_manifest_open(); - * 2. Create an empty resource identified by a FILE *; - * 3. Get a "list" of exposed subject URIs using - * lv2_dyn_manifest_get_subjects(); - * 4. Call lv2_dyn_manifest_get_data() for each URI of interest, in order to - * get data related to that URI (either by calling the function subsequently - * with the same FILE * resource, or by creating more FILE * resources to - * perform parallel calls); - * 5. Call lv2_dyn_manifest_close(); - * 6. Parse the content of the FILE * resource(s). - * 7. Free/delete/unlink the FILE * resource(s). - * - * The content of the FILE * resources has to be interpreted by the host as a - * regular file in Turtle syntax. This also means that each FILE * resource - * should also contain needed prefix definitions, in case any are used. - * - * Each call to lv2_dyn_manifest_open() automatically implies the (re)generation - * of the dynamic manifest on the library side. - * - * When such calls are made, data fetched from the involved library using this - * API before such call is to be considered no more valid. - * - * In case the library uses this same API to access other dynamic manifests, it - * MUST implement some mechanism to avoid potentially endless loops (such as A - * loads B, B loads A, etc.) in functions from the Dynamic manifest open class - * (the open-like operation MUST fail). For this purpose, use of a static - * boolean flag is suggested. - */ - /** Function that (re)generates the dynamic manifest. * - * handle is a pointer to an uninitialized dynamic manifest generator handle. + * @param handle Pointer to an uninitialized dynamic manifest generator handle. * - * features is a NULL terminated array of LV2_Feature structs which + * @param features NULL terminated array of LV2_Feature structs which * represent the features the host supports. The dynamic manifest geenrator may * refuse to (re)generate the dynamic manifest if required features are not * found here (however hosts SHOULD NOT use this as a discovery mechanism, @@ -171,9 +138,9 @@ typedef void * LV2_Dyn_Manifest_Handle; * if a host has no features, it MUST pass a single element array containing * NULL. * - * This function MUST return 0 on success, otherwise a non-zero error code, and - * the host SHOULD evaluate the result of the operation by examining the - * returned value, rather than try to interpret the value of handle. + * @return 0 on success, otherwise a non-zero error code. The host SHOULD + * evaluate the result of the operation by examining the returned value and MUST + * NOT try to interpret the value of handle. */ int lv2_dyn_manifest_open(LV2_Dyn_Manifest_Handle * handle, const LV2_Feature *const * features); @@ -181,61 +148,68 @@ int lv2_dyn_manifest_open(LV2_Dyn_Manifest_Handle * handle, /** Function that fetches a "list" of subject URIs exposed by the dynamic * manifest generator. * - * handle is the dynamic manifest generator handle. - * - * fp is the FILE * identifying the resource the host has to set up for the - * dynamic manifest generator. The host MUST pass a writable, empty resource to - * this function, and the dynamic manifest generator MUST ONLY perform write - * operations on it at the end of the stream (e.g. use only fprintf(), fwrite() - * and similar). - * * The dynamic manifest generator has to fill the resource only with the needed * triples to make the host aware of the "objects" it wants to expose. For - * example, if the library exposes a regular LV2 plugin, it should output only a - * triple like the following: + * example, if the plugin library exposes a regular LV2 plugin, it should output + * only a triple like the following: * * <http://www.example.com/plugin/uri> a lv2:Plugin . * - * This function MUST return 0 on success, otherwise a non-zero error code. + * The objects that are elegible for exposure are those that would need to be + * represented by a subject node in a static manifest. + * + * @param handle Dynamic manifest generator handle. + * + * @param fp FILE * identifying the resource the host has to set up for the + * dynamic manifest generator. The host MUST pass a writable, empty resource to + * this function, and the dynamic manifest generator MUST ONLY perform write + * operations on it at the end of the stream (e.g., using only fprintf(), + * fwrite() and similar). + * + * @return 0 on success, otherwise a non-zero error code. */ int lv2_dyn_manifest_get_subjects(LV2_Dyn_Manifest_Handle handle, FILE * fp); /** Function that fetches data related to a specific URI. * - * handle is the dynamic manifest generator handle. + * The dynamic manifest generator has to fill the resource with data related to + * object represented by the given URI. For example, if the library exposes a + * regular LV2 plugin whose URI, as retrieved by the host using + * lv2_dyn_manifest_get_subjects() is http://www.example.com/plugin/uri, it + * should output something like: + * + * <http://www.example.com/plugin/uri> a lv2:Plugin ; + * doap:name "My Plugin" ; + * lv2:binary <mylib.so> ; + * ... etc... + * + * @param handle Dynamic manifest generator handle. * - * fp is the FILE * identifying the resource the host has to set up for the + * @param fp FILE * identifying the resource the host has to set up for the * dynamic manifest generator. The host MUST pass a writable resource to this * function, and the dynamic manifest generator MUST ONLY perform write - * operations on it at the current position of the stream (e.g. use only + * operations on it at the current position of the stream (e.g. using only * fprintf(), fwrite() and similar). * - * uri is the URI to get data about (in the "plain" form, a.k.a. without RDF - * prefixes). - * - * The dynamic manifest generator has to fill the resource with data related to - * the URI. For example, if the library exposes a regular LV2 plugin whose URI, - * as retrieved by the host using lv2_dyn_manifest_get_subjects() is - * http://www.example.com/plugin/uri, it should output something like: + * @param uri URI to get data about (in the "plain" form, i.e., absolute URI + * without Turtle prefixes). * - * <http://www.example.com/plugin/uri> a lv2:Plugin; - * lv2:binary <mylib.so>; - * doap:name "My Plugin"; - * ... etc... - * - * This function MUST return 0 on success, otherwise a non-zero error code. + * @return 0 on success, otherwise a non-zero error code. */ int lv2_dyn_manifest_get_data(LV2_Dyn_Manifest_Handle handle, FILE * fp, const char * uri); /** Function that ends the operations on the dynamic manifest generator. + * + * This function SHOULD be used by the dynamic manifest generator to perform + * cleanup operations, etc. * - * handle is the dynamic manifest generator handle. + * Once this function is called, referring to handle will cause undefined + * behavior. * - * This function should be used by the dynamic manifest generator to perform - * cleanup operations, etc. + * @param handle Dynamic manifest generator handle. */ void lv2_dyn_manifest_close(LV2_Dyn_Manifest_Handle handle); |