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Diffstat (limited to 'ext/persist.lv2/persist.ttl')
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diff --git a/ext/persist.lv2/persist.ttl b/ext/persist.lv2/persist.ttl deleted file mode 100644 index 697b931..0000000 --- a/ext/persist.lv2/persist.ttl +++ /dev/null @@ -1,208 +0,0 @@ -# LV2 Persist Extension -# Copyright 2010-2011 David Robillard <d@drobilla.net> -# Copyright 2010 Leonard Ritter <paniq@paniq.org> -# -# Permission to use, copy, modify, and/or distribute this software for any -# purpose with or without fee is hereby granted, provided that the above -# copyright notice and this permission notice appear in all copies. -# -# THIS SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES -# WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF -# MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR -# ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES -# WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN -# ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF -# OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE. - -@prefix persist: <http://lv2plug.in/ns/ext/persist#> . -@prefix doap: <http://usefulinc.com/ns/doap#> . -@prefix foaf: <http://xmlns.com/foaf/0.1/> . -@prefix lv2: <http://lv2plug.in/ns/lv2core#> . -@prefix rdf: <http://www.w3.org/1999/02/22-rdf-syntax-ns#> . -@prefix rdfs: <http://www.w3.org/2000/01/rdf-schema#> . -@prefix xsd: <http://www.w3.org/2001/XMLSchema#> . - -<http://lv2plug.in/ns/ext/persist> - a lv2:Specification ; - doap:name "LV2 Persist" ; - doap:license <http://opensource.org/licenses/isc-license> ; - doap:release [ - doap:revision "0.3" ; - doap:created "2011-03-29" - ] ; - doap:developer [ - a foaf:Person ; - foaf:name "Leonard Ritter" ; - foaf:homepage <http://paniq.org> ; - ] ; - doap:maintainer [ - a foaf:Person ; - foaf:name "David Robillard" ; - foaf:homepage <http://drobilla.net/> ; - rdfs:seeAlso <http://drobilla.net/drobilla.rdf> - ] ; - lv2:documentation """ -<p>This extension provides a mechanism for plugins to save and restore state -across instances, allowing hosts to save configuration/state/data with a -project or fully clone (i.e. make a deep copy of) a plugin instance.</p> - -<p>This extension allows plugins to save private state data, i.e. data that is -not contained in input ports. The motivating ideal is for the state of a plugin -instance to be <em>entirely</em> described by port values (as with all LV2 -plugins) and a key/value dictionary as defined by this extension. This -mechanism is simple, yet sufficiently powerful to describe arbitrarily advanced -state.</p> - -<p>The <q>state</q> described by this extension is conceptually a single key/value -dictionary. Keys are URIs, and values are typed-tagged blobs of any type. The -plugin provides a save and restore method for saving and restoring state. To -initiate a save or restore, the host calls these methods, passing a callback to -be used for saving or restoring a key/value pair. This data is available -to the host, allowing state to be easily used in many different way. The -actual mechanism of saving and restoring state is completely abstract from the -plugin's perspective.</p> - -<p>Because the state is a simple dictionary, hosts and plugins can work with -state easily (virtually all programming languages have an appropriate -dictionary type available). Additionally, this format is simple and terse to -serialise in many formats (e.g. any RDF syntax, JSON, XML, key/value databases -such as BDB, etc.). In particular, state can be elegantly described in a -plugin's Turtle description, which is useful for e.g. presets or default -state. Note that these are simply possibilities; this extension defines only a -few function prototypes and does not require the use of any particular syntax, -data structure, file system, or other implementation detail. Hosts are free to -work with plugin state in whatever way is most appropriate for that host.</p> - -<p>This extension makes it possible for plugins to save private data, but state -is not necessarily private, e.g. a plugin could have a public interface for -inspecting and manipulating internal state, which would be saved using this -extension. Plugins and extensions SHOULD express state changes as modifications -to this key/value dictionary, and use meaningful types wherever -possible. Extensions may define a dynamic mechanism for accessing plugin state, -or conventional state keys likely to be useful to several implementations.</p> - -<p>In pseudo code, a typical use case in a plugin is:</p> -<pre class="c-code"> -#define NS_EG "http://example.org/" -#define NS_ATOM "http://lv2plug.in/ns/ext/atom#" -#define NS_XSD "http://www.w3.org/2001/XMLSchema#" - -static const char* const KEY_GREETING = "http://example.org/greeting"; - -LV2_Handle my_instantiate(...) -{ - MyPlugin* plugin = ...; - LV2_URI_Map_Feature* map = ...; - plugin->uri_greeting_key = map->uri_to_id(..., NULL, NS_EG "greeting-key"); - plugin->uri_xsd_string = map->uri_to_id(..., NULL, NS_XSD "string"); - plugin->state->greeting = strdup("Hello"); - return plugin; -} - -void my_save(LV2_Handle instance, - LV2_Persist_Store_Function store, - void* callback_data) -{ - MyPlugin* plugin = (MyPlugin*)instance; - const char* greeting = plugin->state->greeting; - - store(callback_data, - plugin->uri_greeting_key, - greeting, - strlen(greeting) + 1, - plugin->uri_xsd_string, - LV2_PERSIST_IS_POD | LV2_PERSIST_IS_PORTABLE); -} - -void my_restore(LV2_Handle instance, - LV2_Persist_Retrieve_Function retrieve, - void* callback_data) -{ - MyPlugin* plugin = (MyPlugin*)instance; - - size_t size; - uint32_t type; - uint32_t flags; - const char* greeting = retrieve(callback_data, - plugin->uri_greeting_key, - &size, - &type, - &flags); - - if (greeting) { - free(plugin->state->greeting); - plugin->state->greeting = strdup(greeting); - } else { - plugin->state->greeting = strdup("Hello"); - } -} -</pre> - -<p>Similarly, a typical use case in a host is:</p> -<pre class="c-code"> -int store_callback(void* callback_data, - uint32_t key, - const void* value, - size_t size, - uint32_t type, - uint32_t flags) -{ - if ((flags & LV2_PERSIST_IS_POD)) { - /* Keeping state in memory only, if disk was involved then - LV2_PERSIST_IS_PORTABLE would have to be checked as well. - */ - Map* state_map = (Map*)callback_data; - state_map->insert(key, Value(copy(value), size, type, pod)); - return 0; - } else { - return 1; /* Non-POD events are unsupported. */ - } -} - -Map get_plugin_state(LV2_Handle instance) -{ - LV2_Persist* persist = instance.extension_data("http://lv2plug.in/ns/ext/persist"); - Map state_map; - persist.save(instance, store_callback, &state_map); - return state_map; -} -</pre> -""" . - -persist:InstanceState - a rdfs:Class ; - rdfs:label "Plugin Instance State" ; - rdfs:comment """ -This class is used to express a plugin instance's state in RDF. The key/value -properties of the instance form the predicate/object (respectively) of triples -with a persist:InstanceState as the subject (see persist:instanceState for an -example). This may be used wherever it is useful to express a plugin instance's -state in RDF (e.g. for serialisation, storing in a model, or transmitting over -a network). Note that this class is provided because it may be useful for -hosts, plugins, or extensions that work with instance state, but its use is not -required to support the LV2 Persist extension. -""" . - - -persist:instanceState - a rdf:Property ; - rdfs:range persist:InstanceState ; - lv2:documentation """ -Predicate to relate a plugin instance to an InstanceState. This may be used -wherever the state of a particular plugin instance needs to be represented. -Note that the domain of this property is unspecified, since LV2 does not define -any RDF class for plugin instance. This predicate may be used wherever it makes -sense to do so, e.g.: -<pre class="turtle-code"> -@prefix eg: <http://example.org/> . - -<plugininstance> persist:instanceState [ - eg:somekey "some value" ; - eg:someotherkey "some other value" ; - eg:favourite-number 2 . -] -</pre> -Note that this property is provided because it may be useful for hosts, -plugins, or extensions that work with instance state, but its use is not -required to support the LV2 Persist extension. -""" . |