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-rw-r--r--lv2/lv2plug.in/ns/ext/state/lv2-state.doap.ttl66
-rw-r--r--lv2/lv2plug.in/ns/ext/state/manifest.ttl8
-rw-r--r--lv2/lv2plug.in/ns/ext/state/state.h363
-rw-r--r--lv2/lv2plug.in/ns/ext/state/state.ttl382
4 files changed, 0 insertions, 819 deletions
diff --git a/lv2/lv2plug.in/ns/ext/state/lv2-state.doap.ttl b/lv2/lv2plug.in/ns/ext/state/lv2-state.doap.ttl
deleted file mode 100644
index fd87a13..0000000
--- a/lv2/lv2plug.in/ns/ext/state/lv2-state.doap.ttl
+++ /dev/null
@@ -1,66 +0,0 @@
-@prefix dcs: <http://ontologi.es/doap-changeset#> .
-@prefix doap: <http://usefulinc.com/ns/doap#> .
-@prefix foaf: <http://xmlns.com/foaf/0.1/> .
-@prefix rdfs: <http://www.w3.org/2000/01/rdf-schema#> .
-
-<http://lv2plug.in/ns/ext/state>
- a doap:Project ;
- doap:created "2010-11-09" ;
- doap:name "LV2 State" ;
- doap:shortdesc "An interface for LV2 plugins to save and restore state." ;
- doap:license <http://opensource.org/licenses/isc> ;
- doap:developer <http://lv2plug.in/ns/meta#paniq> ,
- <http://drobilla.net/drobilla#me> ;
- doap:maintainer <http://drobilla.net/drobilla#me> ;
- doap:release [
- doap:revision "2.3" ;
- doap:created "2016-10-19" ;
- dcs:blame <http://drobilla.net/drobilla#me> ;
- dcs:changeset [
- dcs:item [
- rdfs:label "Add state:StateChanged for notification events."
- ]
- ]
- ] , [
- doap:revision "2.2" ;
- doap:created "2016-07-31" ;
- doap:file-release <http://lv2plug.in/spec/lv2-1.14.0.tar.bz2> ;
- dcs:blame <http://drobilla.net/drobilla#me> ;
- dcs:changeset [
- dcs:item [
- rdfs:label "Add LV2_STATE_ERR_NO_SPACE status flag."
- ] , [
- rdfs:label "Add state:threadSafeRestore feature for dropout-free state restoration."
- ]
- ]
- ] , [
- doap:revision "2.0" ;
- doap:created "2013-01-16" ;
- doap:file-release <http://lv2plug.in/spec/lv2-1.4.0.tar.bz2> ;
- dcs:blame <http://drobilla.net/drobilla#me> ;
- dcs:changeset [
- dcs:item [
- rdfs:label "Add state:loadDefaultState feature so plugins can have their default state loaded without hard-coding default state as a special case."
- ]
- ]
- ] , [
- doap:revision "1.2" ;
- doap:created "2012-10-14" ;
- doap:file-release <http://lv2plug.in/spec/lv2-1.2.0.tar.bz2> ;
- dcs:blame <http://drobilla.net/drobilla#me> ;
- dcs:changeset [
- dcs:item [
- rdfs:label "Use consistent label style."
- ]
- ]
- ] , [
- doap:revision "1.0" ;
- doap:created "2012-04-17" ;
- doap:file-release <http://lv2plug.in/spec/lv2-1.0.0.tar.bz2> ;
- dcs:blame <http://drobilla.net/drobilla#me> ;
- dcs:changeset [
- dcs:item [
- rdfs:label "Initial release."
- ]
- ]
- ] .
diff --git a/lv2/lv2plug.in/ns/ext/state/manifest.ttl b/lv2/lv2plug.in/ns/ext/state/manifest.ttl
deleted file mode 100644
index 2a54874..0000000
--- a/lv2/lv2plug.in/ns/ext/state/manifest.ttl
+++ /dev/null
@@ -1,8 +0,0 @@
-@prefix lv2: <http://lv2plug.in/ns/lv2core#> .
-@prefix rdfs: <http://www.w3.org/2000/01/rdf-schema#> .
-
-<http://lv2plug.in/ns/ext/state>
- a lv2:Specification ;
- lv2:minorVersion 2 ;
- lv2:microVersion 3 ;
- rdfs:seeAlso <state.ttl> .
diff --git a/lv2/lv2plug.in/ns/ext/state/state.h b/lv2/lv2plug.in/ns/ext/state/state.h
deleted file mode 100644
index f2a4afa..0000000
--- a/lv2/lv2plug.in/ns/ext/state/state.h
+++ /dev/null
@@ -1,363 +0,0 @@
-/*
- Copyright 2010-2016 David Robillard <http://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.
-*/
-
-/**
- @defgroup state State
-
- An interface for LV2 plugins to save and restore state, see
- <http://lv2plug.in/ns/ext/state> for details.
-
- @{
-*/
-
-#ifndef LV2_STATE_H
-#define LV2_STATE_H
-
-#include <stddef.h>
-#include <stdint.h>
-
-#include "lv2/lv2plug.in/ns/lv2core/lv2.h"
-
-#define LV2_STATE_URI "http://lv2plug.in/ns/ext/state" ///< http://lv2plug.in/ns/ext/state
-#define LV2_STATE_PREFIX LV2_STATE_URI "#" ///< http://lv2plug.in/ns/ext/state#
-
-#define LV2_STATE__State LV2_STATE_PREFIX "State" ///< http://lv2plug.in/ns/ext/state#State
-#define LV2_STATE__interface LV2_STATE_PREFIX "interface" ///< http://lv2plug.in/ns/ext/state#interface
-#define LV2_STATE__loadDefaultState LV2_STATE_PREFIX "loadDefaultState" ///< http://lv2plug.in/ns/ext/state#loadDefaultState
-#define LV2_STATE__makePath LV2_STATE_PREFIX "makePath" ///< http://lv2plug.in/ns/ext/state#makePath
-#define LV2_STATE__mapPath LV2_STATE_PREFIX "mapPath" ///< http://lv2plug.in/ns/ext/state#mapPath
-#define LV2_STATE__state LV2_STATE_PREFIX "state" ///< http://lv2plug.in/ns/ext/state#state
-#define LV2_STATE__threadSafeRestore LV2_STATE_PREFIX "threadSafeRestore" ///< http://lv2plug.in/ns/ext/state#threadSafeRestore
-#define LV2_STATE__StateChanged LV2_STATE_PREFIX "StateChanged" ///< http://lv2plug.in/ns/ext/state#StateChanged
-
-#ifdef __cplusplus
-extern "C" {
-#else
-# include <stdbool.h>
-#endif
-
-typedef void* LV2_State_Handle; ///< Opaque handle for state save/restore
-typedef void* LV2_State_Map_Path_Handle; ///< Opaque handle for state:mapPath feature
-typedef void* LV2_State_Make_Path_Handle; ///< Opaque handle for state:makePath feature
-
-/**
- Flags describing value characteristics.
-
- These flags are used along with the value's type URI to determine how to
- (de-)serialise the value data, or whether it is even possible to do so.
-*/
-typedef enum {
- /**
- Plain Old Data.
-
- Values with this flag contain no pointers or references to other areas
- of memory. It is safe to copy POD values with a simple memcpy and store
- them for the duration of the process. A POD value is not necessarily
- safe to trasmit between processes or machines (e.g. filenames are POD),
- see LV2_STATE_IS_PORTABLE for details.
-
- Implementations MUST NOT attempt to copy or serialise a non-POD value if
- they do not understand its type (and thus know how to correctly do so).
- */
- LV2_STATE_IS_POD = 1,
-
- /**
- Portable (architecture independent) data.
-
- Values with this flag are in a format that is usable on any
- architecture. A portable value saved on one machine can be restored on
- another machine regardless of architecture. The format of portable
- values MUST NOT depend on architecture-specific properties like
- endianness or alignment. Portable values MUST NOT contain filenames.
- */
- LV2_STATE_IS_PORTABLE = 1 << 1,
-
- /**
- Native data.
-
- This flag is used by the host to indicate that the saved data is only
- going to be used locally in the currently running process (e.g. for
- instance duplication or snapshots), so the plugin should use the most
- efficient representation possible and not worry about serialisation
- and portability.
- */
- LV2_STATE_IS_NATIVE = 1 << 2
-} LV2_State_Flags;
-
-/** A status code for state functions. */
-typedef enum {
- LV2_STATE_SUCCESS = 0, /**< Completed successfully. */
- LV2_STATE_ERR_UNKNOWN = 1, /**< Unknown error. */
- LV2_STATE_ERR_BAD_TYPE = 2, /**< Failed due to unsupported type. */
- LV2_STATE_ERR_BAD_FLAGS = 3, /**< Failed due to unsupported flags. */
- LV2_STATE_ERR_NO_FEATURE = 4, /**< Failed due to missing features. */
- LV2_STATE_ERR_NO_PROPERTY = 5, /**< Failed due to missing property. */
- LV2_STATE_ERR_NO_SPACE = 6 /**< Failed due to insufficient space. */
-} LV2_State_Status;
-
-/**
- A host-provided function to store a property.
- @param handle Must be the handle passed to LV2_State_Interface.save().
- @param key The key to store `value` under (URID).
- @param value Pointer to the value to be stored.
- @param size The size of `value` in bytes.
- @param type The type of `value` (URID).
- @param flags LV2_State_Flags for `value`.
- @return 0 on success, otherwise a non-zero error code.
-
- The host passes a callback of this type to LV2_State_Interface.save(). This
- callback is called repeatedly by the plugin to store all the properties that
- describe its current state.
-
- DO NOT INVENT NONSENSE URI SCHEMES FOR THE KEY. Best is to use keys from
- existing vocabularies. If nothing appropriate is available, use http URIs
- that point to somewhere you can host documents so documentation can be made
- resolvable (e.g. a child of the plugin or project URI). If this is not
- possible, invent a URN scheme, e.g. urn:myproj:whatever. The plugin MUST
- NOT pass an invalid URI key.
-
- The host MAY fail to store a property for whatever reason, but SHOULD
- store any property that is LV2_STATE_IS_POD and LV2_STATE_IS_PORTABLE.
- Implementations SHOULD use the types from the LV2 Atom extension
- (http://lv2plug.in/ns/ext/atom) wherever possible. The plugin SHOULD
- attempt to fall-back and avoid the error if possible.
-
- Note that `size` MUST be > 0, and `value` MUST point to a valid region of
- memory `size` bytes long (this is required to make restore unambiguous).
-
- The plugin MUST NOT attempt to use this function outside of the
- LV2_State_Interface.restore() context.
-*/
-typedef LV2_State_Status (*LV2_State_Store_Function)(
- LV2_State_Handle handle,
- uint32_t key,
- const void* value,
- size_t size,
- uint32_t type,
- uint32_t flags);
-
-/**
- A host-provided function to retrieve a property.
- @param handle Must be the handle passed to LV2_State_Interface.restore().
- @param key The key of the property to retrieve (URID).
- @param size (Output) If non-NULL, set to the size of the restored value.
- @param type (Output) If non-NULL, set to the type of the restored value.
- @param flags (Output) If non-NULL, set to the flags for the restored value.
- @return A pointer to the restored value (object), or NULL if no value
- has been stored under `key`.
-
- A callback of this type is passed by the host to
- LV2_State_Interface.restore(). This callback is called repeatedly by the
- plugin to retrieve any properties it requires to restore its state.
-
- The returned value MUST remain valid until LV2_State_Interface.restore()
- returns. The plugin MUST NOT attempt to use this function, or any value
- returned from it, outside of the LV2_State_Interface.restore() context.
-*/
-typedef const void* (*LV2_State_Retrieve_Function)(
- LV2_State_Handle handle,
- uint32_t key,
- size_t* size,
- uint32_t* type,
- uint32_t* flags);
-
-/**
- LV2 Plugin State Interface.
-
- When the plugin's extension_data is called with argument
- LV2_STATE__interface, the plugin MUST return an LV2_State_Interface
- structure, which remains valid for the lifetime of the plugin.
-
- The host can use the contained function pointers to save and restore the
- state of a plugin instance at any time, provided the threading restrictions
- of the functions are met.
-
- Stored data is only guaranteed to be compatible between instances of plugins
- with the same URI (i.e. if a change to a plugin would cause a fatal error
- when restoring state saved by a previous version of that plugin, the plugin
- URI MUST change just as it must when ports change incompatibly). Plugin
- authors should consider this possibility, and always store sensible data
- with meaningful types to avoid such problems in the future.
-*/
-typedef struct _LV2_State_Interface {
- /**
- Save plugin state using a host-provided `store` callback.
-
- @param instance The instance handle of the plugin.
- @param store The host-provided store callback.
- @param handle An opaque pointer to host data which MUST be passed as the
- handle parameter to `store` if it is called.
- @param flags Flags describing desired properties of this save. These
- flags may be used to determine the most appropriate values to store.
- @param features Extensible parameter for passing any additional
- features to be used for this save.
-
- The plugin is expected to store everything necessary to completely
- restore its state later. Plugins SHOULD store simple POD data whenever
- possible, and consider the possibility of state being restored much
- later on a different machine.
-
- The `handle` pointer and `store` function MUST NOT be used
- beyond the scope of save().
-
- This function has its own special threading class: it may not be called
- concurrently with any "Instantiation" function, but it may be called
- concurrently with functions in any other class, unless the definition of
- that class prohibits it (e.g. it may not be called concurrently with a
- "Discovery" function, but it may be called concurrently with an "Audio"
- function. The plugin is responsible for any locking or lock-free
- techniques necessary to make this possible.
-
- Note that in the simple case where state is only modified by restore(),
- there are no synchronization issues since save() is never called
- concurrently with restore() (though run() may read it during a save).
-
- Plugins that dynamically modify state while running, however, must take
- care to do so in such a way that a concurrent call to save() will save a
- consistent representation of plugin state for a single instant in time.
- */
- LV2_State_Status (*save)(LV2_Handle instance,
- LV2_State_Store_Function store,
- LV2_State_Handle handle,
- uint32_t flags,
- const LV2_Feature *const * features);
-
- /**
- Restore plugin state using a host-provided `retrieve` callback.
-
- @param instance The instance handle of the plugin.
- @param retrieve The host-provided retrieve callback.
- @param handle An opaque pointer to host data which MUST be passed as the
- handle parameter to `retrieve` if it is called.
- @param flags Currently unused.
- @param features Extensible parameter for passing any additional
- features to be used for this restore.
-
- The plugin MAY assume a restored value was set by a previous call to
- LV2_State_Interface.save() by a plugin with the same URI.
-
- The plugin MUST gracefully fall back to a default value when a value can
- not be retrieved. This allows the host to reset the plugin state with
- an empty map.
-
- The `handle` pointer and `store` function MUST NOT be used
- beyond the scope of restore().
-
- This function is in the "Instantiation" threading class as defined by
- LV2. This means it MUST NOT be called concurrently with any other
- function on the same plugin instance.
- */
- LV2_State_Status (*restore)(LV2_Handle instance,
- LV2_State_Retrieve_Function retrieve,
- LV2_State_Handle handle,
- uint32_t flags,
- const LV2_Feature *const * features);
-} LV2_State_Interface;
-
-/**
- Feature data for state:mapPath (@ref LV2_STATE__mapPath).
-*/
-typedef struct {
- /**
- Opaque host data.
- */
- LV2_State_Map_Path_Handle handle;
-
- /**
- Map an absolute path to an abstract path for use in plugin state.
- @param handle MUST be the `handle` member of this struct.
- @param absolute_path The absolute path of a file.
- @return An abstract path suitable for use in plugin state.
-
- The plugin MUST use this function to map any paths that will be stored
- in plugin state. The returned value is an abstract path which MAY not
- be an actual file system path; absolute_path() MUST be used to map
- it to an actual path in order to use the file.
-
- Plugins MUST NOT make any assumptions about abstract paths except that
- they can be mapped back to the absolute path of the "same" file (though
- not necessarily the same original path) using absolute_path().
-
- This function may only be called within the context of
- LV2_State_Interface methods. The caller is responsible for freeing the
- returned value with free().
- */
- char* (*abstract_path)(LV2_State_Map_Path_Handle handle,
- const char* absolute_path);
-
- /**
- Map an abstract path from plugin state to an absolute path.
- @param handle MUST be the `handle` member of this struct.
- @param abstract_path An abstract path (e.g. a path from plugin state).
- @return An absolute file system path.
-
- The plugin MUST use this function in order to actually open or otherwise
- use any paths loaded from plugin state.
-
- This function may only be called within the context of
- LV2_State_Interface methods. The caller is responsible for freeing the
- returned value with free().
- */
- char* (*absolute_path)(LV2_State_Map_Path_Handle handle,
- const char* abstract_path);
-} LV2_State_Map_Path;
-
-/**
- Feature data for state:makePath (@ref LV2_STATE__makePath).
-*/
-typedef struct {
- /**
- Opaque host data.
- */
- LV2_State_Make_Path_Handle handle;
-
- /**
- Return a path the plugin may use to create a new file.
- @param handle MUST be the `handle` member of this struct.
- @param path The path of the new file within a namespace unique to this
- plugin instance.
- @return The absolute path to use for the new file.
-
- This function can be used by plugins to create files and directories,
- either at state saving time (if this feature is passed to
- LV2_State_Interface.save()) or any time (if this feature is passed to
- LV2_Descriptor.instantiate()).
-
- The host MUST do whatever is necessary for the plugin to be able to
- create a file at the returned path (e.g. using fopen), including
- creating any leading directories.
-
- If this function is passed to LV2_Descriptor.instantiate(), it may be
- called from any non-realtime context. If it is passed to
- LV2_State_Interface.save(), it may only be called within the dynamic
- scope of that function call.
-
- The caller is responsible for freeing the returned value with free().
- */
- char* (*path)(LV2_State_Make_Path_Handle handle,
- const char* path);
-} LV2_State_Make_Path;
-
-#ifdef __cplusplus
-} /* extern "C" */
-#endif
-
-#endif /* LV2_STATE_H */
-
-/**
- @}
-*/
diff --git a/lv2/lv2plug.in/ns/ext/state/state.ttl b/lv2/lv2plug.in/ns/ext/state/state.ttl
deleted file mode 100644
index c86fea7..0000000
--- a/lv2/lv2plug.in/ns/ext/state/state.ttl
+++ /dev/null
@@ -1,382 +0,0 @@
-@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 state: <http://lv2plug.in/ns/ext/state#> .
-
-<http://lv2plug.in/ns/ext/state>
- a lv2:Specification ;
- rdfs:seeAlso <state.h> ,
- <lv2-state.doap.ttl> ;
- lv2:documentation """
-<p>This extension defines a simple mechanism which allows hosts to save and
-restore a plugin instance's state. The goal is for an instance's state to be
-<em>completely</em> described by port values (as with all LV2 plugins) and a
-simple dictionary.</p>
-
-<p>The <q>state</q> defined here is conceptually a key:value dictionary, with
-URI keys and values of any type. For performance reasons the key and value
-type are actually a <q>URID</q>, a URI mapped to an integer. A single
-key:value pair is called a <q>property</q>.</p>
-
-<p>This state model is simple yet has many benefits:</p>
-<ul>
- <li>Both fast and extensible thanks to URID keys.</li>
- <li>No limitations on possible value types.</li>
- <li>Easy to serialise in almost any format.</li>
- <li>Easy to store in a typical <q>map</q> or <q>dictionary</q> data
- structure.</li>
- <li>Elegantly described in Turtle, so state can be described in LV2 data
- files (including presets).</li>
- <li>Does not impose any file formats, data structures, or file system
- requirements.</li>
- <li>Suitable for portable persistent state as well as fast in-memory
- snapshots.</li>
- <li>Keys <em>may</em> be well-defined and used meaningfully across several
- implementations.</li>
- <li>State <em>may</em> be dynamic, but plugins are not required to have a
- dynamic dictionary data structure available.</li>
-</ul>
-
-<p>To implement state, the plugin provides a state:interface to the host. To
-save or restore, the host calls LV2_State_Interface::save() or
-LV2_State_Interface::restore(), passing a callback to be used for handling a
-single property. The host is free to implement property storage and retrieval
-in any way.</p>
-
-<p>Since value types are defined by URI, any type is possible. However, a set
-of standard types is defined by the <a href="../atom/atom.html">LV2 Atom</a>
-extension. Use of these types is recommended. Hosts MUST implement at least
-<a href="../atom/atom.html#String">atom:String</a>, which is simply a C
-string.</p>
-
-<h3>Referring to Files</h3>
-
-<p>Plugins may need to refer to existing files (e.g. loaded samples) in their
-state. This is done by storing the file's path as a property just like any
-other value. However, there are some rules which MUST be followed when storing
-paths, see state:mapPath for details. Plugins MUST use the type <a
-href="../atom/atom.html#Path">atom:Path</a> for all paths in their state.</p>
-
-<p>Plugins are strongly encouraged to avoid creating files, instead storing all
-state as properties. However, occasionally the ability to create files is
-necessary. To make this possible, the host can provide the feature
-state:makePath which allocates paths for plugin-created files. Plugins MUST
-NOT create files in any other locations.</p>
-
-<h3>Plugin Code Example</h3>
-
-<pre class="c-code">
-
-/* Namespace for this plugin's keys. This SHOULD be something that could be
- published as a document, even if that document does not exist right now.
-*/
-#define NS_MY "http://example.org/myplugin/schema#"
-
-#define DEFAULT_GREETING "Hello"
-
-LV2_Handle
-my_instantiate(...)
-{
- MyPlugin* plugin = ...;
- plugin->uris.atom_String = map_uri(LV2_ATOM__String);
- plugin->uris.my_greeting = map_uri(NS_MY "greeting");
- plugin->state.greeting = strdup(DEFAULT_GREETING);
- return plugin;
-}
-
-LV2_State_Status
-my_save(LV2_Handle instance,
- LV2_State_Store_Function store,
- LV2_State_Handle handle,
- uint32_t flags,
- const LV2_Feature *const * features)
-{
- MyPlugin* plugin = (MyPlugin*)instance;
- const char* greeting = plugin->state.greeting;
-
- store(handle,
- plugin->uris.my_greeting,
- greeting,
- strlen(greeting) + 1, // Careful! Need space for terminator
- plugin->uris.atom_String,
- LV2_STATE_IS_POD | LV2_STATE_IS_PORTABLE);
-
- return LV2_STATE_SUCCESS;
-}
-
-LV2_State_Status
-my_restore(LV2_Handle instance,
- LV2_State_Retrieve_Function retrieve,
- LV2_State_Handle handle,
- uint32_t flags,
- const LV2_Feature *const * features)
-{
- MyPlugin* plugin = (MyPlugin*)instance;
-
- size_t size;
- uint32_t type;
- uint32_t flags;
- const char* greeting = retrieve(
- handle, plugin->uris.my_greeting, &amp;size, &amp;type, &amp;flags);
-
- if (greeting) {
- free(plugin->state->greeting);
- plugin->state->greeting = strdup(greeting);
- } else {
- plugin->state->greeting = strdup(DEFAULT_GREETING);
- }
-
- return LV2_STATE_SUCCESS;
-}
-
-const void*
-my_extension_data(const char* uri)
-{
- static const LV2_State_Interface state_iface = { my_save, my_restore };
- if (!strcmp(uri, LV2_STATE__interface)) {
- return &amp;state_iface;
- }
-}
-</pre>
-
-<h3>Host Code Example</h3>
-
-<pre class="c-code">
-LV2_State_Status
-store_callback(LV2_State_Handle handle,
- uint32_t key,
- const void* value,
- size_t size,
- uint32_t type,
- uint32_t flags)
-{
- if ((flags &amp; LV2_STATE_IS_POD)) {
- /* We only care about POD since we're keeping state in memory only.
- For disk or network use, LV2_STATE_IS_PORTABLE must also be checked.
- */
- Map* state_map = (Map*)handle;
- state_map->insert(key, Value(copy(value), size, type));
- return 0;
- } else {
- return 1; /* Non-POD events are unsupported. */
- }
-}
-
-Map
-get_plugin_state(LV2_Handle instance)
-{
- LV2_State* state = instance.extension_data(LV2_STATE__interface);
- Map state_map;
- /** Request a fast/native/POD save, since we're just copying in memory */
- state.save(instance, store_callback, &amp;state_map,
- LV2_STATE_IS_POD|LV2_STATE_IS_NATIVE);
- return state_map;
-}
-</pre>
-
-<h3>Extensions to this Specification</h3>
-
-<p>It is likely that other interfaces for working with plugin state will be
-developed as needed. This is encouraged, however everything SHOULD work within
-the state <em>model</em> defined here. That is, <strong>do not complicate the
-state model</strong>. Implementations can assume the following:</p>
-
-<ul>
-<li>The current port values and state dictionary completely describe a plugin
-instance, at least well enough that saving and restoring will yield an
-<q>identical</q> instance from the user's perspective.</li>
-<li>Hosts are not expected to save and/or restore any other attributes of a
-plugin instance.</li>
-</ul>
-
-<h3>The <q>Property Principle</q></h3>
-
-<p>The main benefit of this meaningful state model is that it can double as a
-plugin control/query mechanism. For plugins that require more advanced control
-than simple control ports, instead of defining a set of commands, define
-properties whose values can be set appropriately. This provides both a way to
-control and save that state <q>for free</q>, since there is no need to define
-commands <em>and</em> a set of properties for storing their effects. In
-particular, this is a good way for UIs to achieve more advanced control of
-plugins.</p>
-
-<p>This <q>property principle</q> is summed up in the phrase:
-<q>Don't stop; set playing to false</q>.</p>
-
-<p>This extension does not define a dynamic mechanism for state access and
-manipulation. The <a href="../patch/patch.html">LV2 Patch</a> extension
-defines a generic set of messages which can be used to access or manipulate
-properties, and the <a href="../atom/atom.html">LV2 Atom</a> extension defines
-a port type and data container capable of transmitting those messages.</p>
-""" .
-
-state:interface
- a lv2:ExtensionData ;
- lv2:documentation """
-<p>A structure (LV2_State_Interface) which contains functions to be called by
-the host to save and restore state. In order to support this extension, the
-plugin must return a valid LV2_State_Interface from
-LV2_Descriptor::extension_data() when it is called with URI
-LV2_STATE__interface.</p>
-
-<p>The plugin data file should describe this like so:</p>
-<pre class="turtle-code">
-@prefix state: &lt;http://lv2plug.in/ns/ext/state#&gt; .
-
-&lt;plugin&gt;
- a lv2:Plugin ;
- lv2:extensionData state:interface .
-</pre>
-""" .
-
-state:State
- a rdfs:Class ;
- rdfs:label "State" ;
- lv2:documentation """
-<p>A state dictionary. This type should be used wherever instance state is
-described. The properties of a resource with this type correspond directly to
-the properties of the state dictionary (except the property that states it has
-this type).</p>
-""" .
-
-state:loadDefaultState
- a lv2:Feature ;
- lv2:documentation """
-<p>This feature indicates that the plugin has default state listed with the
-state:state property which should be loaded by the host before running the
-plugin. Requiring this feature allows plugins to implement a single state
-loading mechanism which works for initialisation as well as restoration,
-without having to hard-code default state.</p>
-
-<p>To support this feature, the host MUST <q>restore</q> the default state
-after instantiating the plugin but before calling run().</p>
-""" .
-
-state:state
- a rdf:Property ;
- rdfs:label "state" ;
- rdfs:range state:State ;
- lv2:documentation """
-<p>The state of this instance. This property may be used anywhere a state
-needs to be described, for example:</p>
-
-<pre class="turtle-code">
-@prefix eg: &lt;http://example.org/&gt; .
-
-&lt;plugin-instance&gt;
- state:state [
- eg:somekey "some value" ;
- eg:someotherkey "some other value" ;
- eg:favourite-number 2
- ] .
-</pre>
-""" .
-
-state:mapPath
- a lv2:Feature ;
- rdfs:label "map file paths" ;
- lv2:documentation """
-<p>This feature maps absolute paths to/from <q>abstract paths</q> which are
-stored in state. To support this feature a host must pass an LV2_Feature with
-URI LV2_STATE__mapPath and data pointed to an LV2_State_Map_Path to the
-plugin's LV2_State_Interface methods.</p>
-
-<p>The plugin MUST map <em>all</em> paths stored in its state (including those
-inside any files in its state). This is necessary to enable host to handle
-file system references correctly, e.g. for distribution or archival.</p>
-
-<p>For example, a plugin may write a path to a state file like so:</p>
-
-<pre class="c-code">
-void write_path(LV2_State_Map_Path* map_path, FILE* myfile, const char* path)
-{
- char* abstract_path = map_path->abstract_path(map_path->handle, path);
- fprintf(myfile, "%s", abstract_path);
- free(abstract_path);
-}
-</pre>
-
-<p>Then, later reload the path like so:</p>
-
-<pre class="c-code">
-char* read_path(LV2_State_Map_Path* map_path, FILE* myfile)
-{
- /* Obviously this is not production quality code! */
- char abstract_path[1024];
- fscanf(myfile, "%s", abstract_path);
- return map_path->absolute_path(map_path->handle, abstract_path);
-}
-</pre>
-""" .
-
-state:makePath
- a lv2:Feature ;
- rdfs:label "create new file paths" ;
- lv2:documentation """
-<p>This feature allows plugins to create new files and/or directories. To
-support this feature the host passes an LV2_Feature with URI
-LV2_STATE__makePath and data pointed to an LV2_State_Make_Path to the plugin.
-The host may make this feature available only during save by passing it to
-LV2_State_Interface::save(), or available any time by passing it to
-LV2_Descriptor::instantiate(). If passed to LV2_State_Interface::save(), the
-feature MUST NOT be used beyond the scope of that call.</p>
-
-<p>The plugin is guaranteed a hierarchical namespace unique to that plugin
-instance, and may expect the returned path to have the requested path as a
-suffix. There is <em>one</em> such namespace, even if the feature is passed to
-both LV2_Descriptor::instantiate() <em>and</em> LV2_State_Interface::save().
-Beyond this, the plugin MUST NOT make any assumptions about the returned
-paths.</p>
-
-<p>Like any other paths, the plugin MUST map these paths using state:mapPath
-before storing them in state. The plugin MUST NOT assume these paths will be
-available across a save/restore otherwise, i.e. only mapped paths saved to
-state are persistent, any other created paths are temporary.</p>
-
-<p>For example, a plugin may create a file in a subdirectory like so:</p>
-
-<pre class="c-code">
-char* save_myfile(LV2_State_Make_Path* make_path)
-{
- char* path = make_path->path(make_path->handle, "foo/bar/myfile.txt");
- FILE* myfile = fopen(path, 'w');
- fprintf(myfile, "I am some data");
- fclose(myfile);
- return path;
-}
-</pre>
-""" .
-
-state:threadSafeRestore
- a lv2:Feature ;
- rdfs:label "thread-safe restore" ;
- lv2:documentation """
-<p>If a plugin supports this feature, its LV2_State_Interface::restore method
-is thread-safe and may be called concurrently with audio class functions.</p>
-
-<p>To support this feature, the host MUST pass a <a
-href="../worker/worker.html#schedule">work:schedule</a> feature to the restore
-method, which will be used to complete the state restoration. The usual
-mechanics of the worker apply: the host will call the plugin's work method,
-which emits a response which is later applied in the audio thread.</p>
-
-<p>The host is not required to block run() while restore() and work() load the
-state, so this feature allows state to be restored without dropouts.</p>
-""" .
-
-state:Changed
- a rdfs:Class ;
- rdfs:label "State changed" ;
- lv2:documentation """
-<p>A notification that the internal state of the plugin has been changed in a
-way that the host can not otherwise know about.</p>
-
-<p>This is a one-way notification, intended to be used as the type of an <a
-href="../atom/atom.html#Object">Object</a> sent from plugins when
-necessary.</p>
-
-<p>Plugins SHOULD emit such an event whenever a change has occurred that would
-result in a different state being saved, but not when the host explicity makes
-a change which it knows is likely to have that effect, such as changing a
-parameter.</p>
-""" .