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authorDavid Robillard <d@drobilla.net>2022-07-07 18:59:32 -0400
committerDavid Robillard <d@drobilla.net>2022-07-17 18:14:00 -0400
commit1eccbe4355685b322194df72b5de2382d5290b3b (patch)
tree0677b5c2f577a5024c351a164527f4bdd91a639b /lv2/state
parentd4a970f6962dda28133290194832b726b566ddab (diff)
downloadlv2-1eccbe4355685b322194df72b5de2382d5290b3b.tar.xz
Rearrange source tree to be directly usable by dependants
This allows the LV2 source distribution to be used as an include path for compilers and an LV2_PATH for applications, at the expense of self-contained bundles. That's a nice idea, but it made LV2 itself weird and annoying to depend on. This rearranges things so that directories in the source tree correspond more closely to installation directories. To make this possible, the "aux" directory in the documentation output has been changed to "style", to avoid the reserved name "aux" on Windows.
Diffstat (limited to 'lv2/state')
-rw-r--r--lv2/state/manifest.ttl9
-rw-r--r--lv2/state/meson.build40
-rw-r--r--lv2/state/state.h392
-rw-r--r--lv2/state/state.meta.ttl477
-rw-r--r--lv2/state/state.ttl61
5 files changed, 0 insertions, 979 deletions
diff --git a/lv2/state/manifest.ttl b/lv2/state/manifest.ttl
deleted file mode 100644
index e56c4e5..0000000
--- a/lv2/state/manifest.ttl
+++ /dev/null
@@ -1,9 +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 10 ;
- rdfs:seeAlso <state.ttl> .
-
diff --git a/lv2/state/meson.build b/lv2/state/meson.build
deleted file mode 100644
index 7914797..0000000
--- a/lv2/state/meson.build
+++ /dev/null
@@ -1,40 +0,0 @@
-# Copyright 2022 David Robillard <d@drobilla.net>
-# SPDX-License-Identifier: CC0-1.0 OR ISC
-
-name = 'state'
-path = 'ns' / 'ext' / 'state'
-
-state_data = files(
- 'state.meta.ttl',
- 'state.ttl',
- 'manifest.ttl',
-)
-
-headers = files(
- 'state.h',
-)
-
-# Install specification bundle
-install_data(state_data, install_dir: lv2dir / name + '.lv2')
-install_headers(headers, subdir: 'lv2' / name)
-if get_option('old_headers')
- install_headers(headers, subdir: 'lv2' / 'lv2plug.in' / path)
-endif
-
-# Build documentation
-if build_docs
- lv2_state_docs = custom_target(
- name + '.html',
- command: lv2specgen_command_prefix + [
- '--docdir=../../html',
- '--style-uri=../../aux/style.css',
- '@INPUT@',
- '@OUTPUT@',
- ],
- depends: doc_deps,
- input: files('state.ttl'),
- install: true,
- install_dir: lv2_docdir / 'ns' / 'ext',
- output: name + '.html',
- )
-endif
diff --git a/lv2/state/state.h b/lv2/state/state.h
deleted file mode 100644
index 01ec598..0000000
--- a/lv2/state/state.h
+++ /dev/null
@@ -1,392 +0,0 @@
-/*
- Copyright 2010-2016 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.
-*/
-
-#ifndef LV2_STATE_H
-#define LV2_STATE_H
-
-/**
- @defgroup state State
- @ingroup lv2
-
- An interface for LV2 plugins to save and restore state.
-
- See <http://lv2plug.in/ns/ext/state> for details.
-
- @{
-*/
-
-#include "lv2/core/lv2.h"
-
-#include <stddef.h>
-#include <stdint.h>
-
-// clang-format off
-
-#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__freePath LV2_STATE_PREFIX "freePath" ///< http://lv2plug.in/ns/ext/state#freePath
-#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
-
-// clang-format on
-
-#ifdef __cplusplus
-extern "C" {
-#endif
-
-typedef void* LV2_State_Handle; ///< Opaque handle for state save/restore
-typedef void*
- LV2_State_Free_Path_Handle; ///< Opaque handle for state:freePath feature
-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 transmit between processes or machines (for example, 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 = 1u << 0u,
-
- /**
- 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 = 1u << 1u,
-
- /**
- 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 (for things
- like 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 = 1u << 2u
-} 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 (typically 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 {
- /**
- 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 (for example, 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 must free the returned value
- with LV2_State_Free_Path.free_path().
- */
- 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 (typically 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 must free the returned value
- with LV2_State_Free_Path.free_path().
- */
- 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 (for example, 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 must free the returned value with
- LV2_State_Free_Path.free_path().
- */
- char* (*path)(LV2_State_Make_Path_Handle handle, const char* path);
-} LV2_State_Make_Path;
-
-/**
- Feature data for state:freePath (@ref LV2_STATE__freePath).
-*/
-typedef struct {
- /**
- Opaque host data.
- */
- LV2_State_Free_Path_Handle handle;
-
- /**
- Free a path returned by a state feature.
-
- @param handle MUST be the `handle` member of this struct.
- @param path The path previously returned by a state feature.
-
- This function can be used by plugins to free paths allocated by the host
- and returned by state features (LV2_State_Map_Path.abstract_path(),
- LV2_State_Map_Path.absolute_path(), and LV2_State_Make_Path.path()).
- */
- void (*free_path)(LV2_State_Free_Path_Handle handle, char* path);
-} LV2_State_Free_Path;
-
-#ifdef __cplusplus
-} /* extern "C" */
-#endif
-
-/**
- @}
-*/
-
-#endif /* LV2_STATE_H */
diff --git a/lv2/state/state.meta.ttl b/lv2/state/state.meta.ttl
deleted file mode 100644
index cebe0ac..0000000
--- a/lv2/state/state.meta.ttl
+++ /dev/null
@@ -1,477 +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 lv2: <http://lv2plug.in/ns/lv2core#> .
-@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 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 "2.10" ;
- doap:created "2022-05-26" ;
- doap:file-release <http://lv2plug.in/spec/lv2-1.18.4.tar.bz2> ;
- dcs:blame <http://drobilla.net/drobilla#me> ;
- dcs:changeset [
- dcs:item [
- rdfs:label "Fix spelling errors."
- ]
- ]
- ] , [
- doap:revision "2.8" ;
- doap:created "2021-01-07" ;
- doap:file-release <http://lv2plug.in/spec/lv2-1.18.2.tar.bz2> ;
- dcs:blame <http://drobilla.net/drobilla#me> ;
- dcs:changeset [
- dcs:item [
- rdfs:label "Fix state:StateChanged URI in metadata and documentation."
- ]
- ]
- ] , [
- doap:revision "2.6" ;
- doap:created "2020-04-26" ;
- doap:file-release <http://lv2plug.in/spec/lv2-1.18.0.tar.bz2> ;
- dcs:blame <http://drobilla.net/drobilla#me> ;
- dcs:changeset [
- dcs:item [
- rdfs:label "Add state:freePath feature."
- ]
- ]
- ] , [
- doap:revision "2.4" ;
- doap:created "2019-02-03" ;
- doap:file-release <http://lv2plug.in/spec/lv2-1.16.0.tar.bz2> ;
- 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."
- ]
- ]
- ] ;
- lv2:documentation """
-
-This extension defines a simple mechanism that allows hosts to save and restore
-a plugin instance's state. The goal is for an instance's state to be
-completely described by port values and a simple dictionary.
-
-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 "URID", a URI mapped to an integer. A single key:value pair is
-called a "property".
-
-This state model is simple yet has many benefits:
-
- * Both fast and extensible thanks to URID keys.
-
- * No limitations on possible value types.
-
- * Easy to serialise in almost any format.
-
- * Easy to store in a typical "map" or "dictionary" data structure.
-
- * Elegantly described in Turtle, so state can be described in LV2 data files
- (including presets).
-
- * Does not impose any file formats, data structures, or file system
- requirements.
-
- * Suitable for portable persistent state as well as fast in-memory snapshots.
-
- * Keys _may_ be well-defined and used meaningfully across several
- implementations.
-
- * State _may_ be dynamic, but plugins are not required to have a dynamic
- dictionary data structure available.
-
-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.
-
-Since value types are defined by URI, any type is possible. However, a set of
-standard types is defined by the [LV2 Atom](atom.html) extension. Use of these
-types is recommended. Hosts MUST implement at least
-[atom:String](atom.html#String), which is simply a C string.
-
-### Referring to Files
-
-Plugins may need to refer to existing files (such as 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
-[atom:Path](atom.html#Path) for all paths in their state.
-
-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.
-
-### Plugin Code Example
-
- :::c
-
- /* 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, &size, &type, &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 &state_iface;
- }
- }
-
-### Host Code Example
-
- :::c
- 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 & LV2_STATE_IS_POD)) {
- // We only care about POD since we're keeping state in memory only.
- // Disk or network use would also require LV2_STATE_IS_PORTABLE.
- Map* state_map = (Map*)handle;
- state_map->insert(key, Value(copy(value), size, type));
- return LV2_STATE_SUCCESS;;
- } else {
- return LV2_STATE_ERR_BAD_FLAGS; // Non-POD events are unsupported
- }
- }
-
- Map
- get_plugin_state(LV2_Handle instance)
- {
- LV2_State* state = instance.extension_data(LV2_STATE__interface);
-
- // Request a fast/native/POD save, since we're just copying in memory
- Map state_map;
- state.save(instance, store_callback, &state_map,
- LV2_STATE_IS_POD|LV2_STATE_IS_NATIVE);
-
- return state_map;
- }
-
-### Extensions to this Specification
-
-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 _model_ defined here. That is, **do not complicate the state
-model**. Implementations can assume the following:
-
- * The current port values and state dictionary completely describe a plugin
- instance, at least well enough that saving and restoring will yield an
- "identical" instance from the user's perspective.
-
- * Hosts are not expected to save and/or restore any other attributes of a
- plugin instance.
-
-### The "Property Principle"
-
-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 "for free", since there is no need to define
-commands _and_ a set of properties for storing their effects. In particular,
-this is a good way for UIs to achieve more advanced control of plugins.
-
-This "property principle" is summed up in the phrase: "Don't stop; set playing
-to false".
-
-This extension does not define a dynamic mechanism for state access and
-manipulation. The [LV2 Patch](patch.html) extension defines a generic set of
-messages which can be used to access or manipulate properties, and the [LV2
-Atom](atom.html) extension defines a port type and data container capable of
-transmitting those messages.
-
-"""^^lv2:Markdown .
-
-state:interface
- lv2:documentation """
-
-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.
-
-The plugin data file should describe this like so:
-
- :::turtle
- @prefix state: <http://lv2plug.in/ns/ext/state#> .
-
- <plugin>
- a lv2:Plugin ;
- lv2:extensionData state:interface .
-
-"""^^lv2:Markdown .
-
-state:State
- lv2:documentation """
-
-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).
-
-"""^^lv2:Markdown .
-
-state:loadDefaultState
- lv2:documentation """
-
-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.
-
-To support this feature, the host MUST restore the default state after
-instantiating the plugin but before calling run().
-
-"""^^lv2:Markdown .
-
-state:state
- lv2:documentation """
-
-This property may be used anywhere a state needs to be described, for example:
-
- :::turtle
- @prefix eg: <http://example.org/> .
-
- <plugin-instance>
- state:state [
- eg:somekey "some value" ;
- eg:someotherkey "some other value" ;
- eg:favourite-number 2
- ] .
-
-"""^^lv2:Markdown .
-
-state:mapPath
- lv2:documentation """
-
-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.
-
-The plugin MUST map _all_ paths stored in its state (including those inside any
-files). This is necessary so that hosts can handle file system references
-correctly, for example to share common files, or bundle state for distribution
-or archival.
-
-For example, a plugin may write a path to a state file like so:
-
- :::c
- 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);
- }
-
-Then, later reload the path like so:
-
- :::c
- 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);
- }
-
-"""^^lv2:Markdown .
-
-state:makePath
- lv2:documentation """
-
-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.
-
-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 one such namespace, even if the feature is passed to both
-LV2_Descriptor::instantiate() and LV2_State_Interface::save(). Beyond this,
-the plugin MUST NOT make any assumptions about the returned paths.
-
-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, that is, only mapped paths saved to
-state are persistent, any other created paths are temporary.
-
-For example, a plugin may create a file in a subdirectory like so:
-
- :::c
- 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;
- }
-
-"""^^lv2:Markdown .
-
-state:threadSafeRestore
- lv2:documentation """
-
-If a plugin supports this feature, its LV2_State_Interface::restore method is
-thread-safe and may be called concurrently with audio class functions.
-
-To support this feature, the host MUST pass a
-[work:schedule](worker.html#schedule) 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.
-
-The host is not required to block audio processing while restore() and work()
-load the state, so this feature allows state to be restored without dropouts.
-
-"""^^lv2:Markdown .
-
-state:freePath
- lv2:documentation """
-
-This feature provides a function that can be used by plugins to free paths that
-were allocated by the host via other state features (state:mapPath and
-state:makePath).
-
-"""^^lv2:Markdown .
-
-state:StateChanged
- lv2:documentation """
-
-A notification that the internal state of the plugin has been changed in a way
-that the host can not otherwise know about.
-
-This is a one-way notification, intended to be used as the type of an
-[Object](atom.html#Object) sent from plugins when necessary.
-
-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 explicitly makes
-a change which it knows is likely to have that effect, such as changing a
-parameter.
-
-"""^^lv2:Markdown .
-
diff --git a/lv2/state/state.ttl b/lv2/state/state.ttl
deleted file mode 100644
index 48537c8..0000000
--- a/lv2/state/state.ttl
+++ /dev/null
@@ -1,61 +0,0 @@
-@prefix lv2: <http://lv2plug.in/ns/lv2core#> .
-@prefix owl: <http://www.w3.org/2002/07/owl#> .
-@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 owl:Ontology ;
- rdfs:label "LV2 State" ;
- rdfs:comment "An interface for LV2 plugins to save and restore state." ;
- rdfs:seeAlso <state.h> ,
- <state.meta.ttl> ;
- owl:imports <http://lv2plug.in/ns/lv2core> .
-
-state:interface
- a lv2:ExtensionData ;
- rdfs:label "interface" ;
- rdfs:comment "A plugin interface for saving and restoring state." .
-
-state:State
- a rdfs:Class ;
- rdfs:label "State" ;
- rdfs:comment "LV2 plugin state." .
-
-state:loadDefaultState
- a lv2:Feature ;
- rdfs:label "load default state" ;
- rdfs:comment "A feature indicating that the plugin has default state." .
-
-state:state
- a rdf:Property ,
- owl:ObjectProperty ;
- rdfs:label "state" ;
- rdfs:range state:State ;
- rdfs:comment "The state of an LV2 plugin instance." .
-
-state:mapPath
- a lv2:Feature ;
- rdfs:label "map path" ;
- rdfs:comment "A feature for mapping between absolute and abstract file paths." .
-
-state:makePath
- a lv2:Feature ;
- rdfs:label "make path" ;
- rdfs:comment "A feature for creating new files and directories." .
-
-state:threadSafeRestore
- a lv2:Feature ;
- rdfs:label "thread-safe restore" ;
- rdfs:comment "A feature indicating support for thread-safe state restoration." .
-
-state:freePath
- a lv2:Feature ;
- rdfs:label "free path" ;
- rdfs:comment "A feature for freeing paths allocated by the host." .
-
-state:StateChanged
- a rdfs:Class ;
- rdfs:label "State Changed" ;
- rdfs:comment "A notification that the internal state of the plugin has changed." .
-