From ed78bbe5ba12be1f9bcc736f14c51da6b4f639f3 Mon Sep 17 00:00:00 2001 From: David Robillard Date: Wed, 8 Feb 2012 04:56:24 +0000 Subject: Rearrange tree so top level can be used as an include path for standard style LV2 includes. --- lv2/ns/ext/state/ext.pc.in | 1 - lv2/ns/ext/state/manifest.ttl | 8 - lv2/ns/ext/state/state.h | 359 ------------------------------------------ lv2/ns/ext/state/state.ttl | 359 ------------------------------------------ lv2/ns/ext/state/waf | 1 - lv2/ns/ext/state/wscript | 1 - 6 files changed, 729 deletions(-) delete mode 120000 lv2/ns/ext/state/ext.pc.in delete mode 100644 lv2/ns/ext/state/manifest.ttl delete mode 100644 lv2/ns/ext/state/state.h delete mode 100644 lv2/ns/ext/state/state.ttl delete mode 120000 lv2/ns/ext/state/waf delete mode 120000 lv2/ns/ext/state/wscript (limited to 'lv2/ns/ext/state') diff --git a/lv2/ns/ext/state/ext.pc.in b/lv2/ns/ext/state/ext.pc.in deleted file mode 120000 index 82b50df..0000000 --- a/lv2/ns/ext/state/ext.pc.in +++ /dev/null @@ -1 +0,0 @@ -../../../../ext.pc.in \ No newline at end of file diff --git a/lv2/ns/ext/state/manifest.ttl b/lv2/ns/ext/state/manifest.ttl deleted file mode 100644 index bff9ad5..0000000 --- a/lv2/ns/ext/state/manifest.ttl +++ /dev/null @@ -1,8 +0,0 @@ -@prefix lv2: . -@prefix rdfs: . - - - a lv2:Specification ; - lv2:minorVersion 0 ; - lv2:microVersion 5 ; - rdfs:seeAlso . diff --git a/lv2/ns/ext/state/state.h b/lv2/ns/ext/state/state.h deleted file mode 100644 index b450b93..0000000 --- a/lv2/ns/ext/state/state.h +++ /dev/null @@ -1,359 +0,0 @@ -/* - Copyright 2010-2012 David Robillard - Copyright 2010 Leonard Ritter - - 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. -*/ - -/** - @file - C API for the LV2 State extension . -*/ - -#ifndef LV2_STATE_H -#define LV2_STATE_H - -#include -#include - -#include "lv2/lv2plug.in/ns/lv2core/lv2.h" - -#ifdef __cplusplus -extern "C" { -#else -# include -#endif - -#define LV2_STATE_URI "http://lv2plug.in/ns/ext/state" - -#define LV2_STATE_INTERFACE_URI LV2_STATE_URI "#Interface" -#define LV2_STATE_PATH_URI LV2_STATE_URI "#Path" -#define LV2_STATE_MAP_PATH_URI LV2_STATE_URI "#mapPath" -#define LV2_STATE_MAKE_PATH_URI LV2_STATE_URI "#makePath" - -typedef void* LV2_State_Handle; -typedef void* LV2_State_Map_Path_Handle; -typedef void* LV2_State_Make_Path_Handle; - -/** - 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 references to non-persistent or - non-global resources (e.g. pointers, handles, local paths, etc.). It is - safe to copy POD values with a simple memcpy and store them for use at - any time in the future on a machine with a compatible architecture - (e.g. the same endianness and alignment). - - 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, i.e. if the value is saved on one machine it can safely be - restored on another machine regardless of endianness, alignment, etc. - */ - 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 host-provided function to store a property. - @param handle Must be the handle passed to LV2_State_Interface.save(). - @param key The key (predicate) to store @c value under (URI mapped integer). - @param value Pointer to the value (object) to be stored. - @param size The size of the data at @c value in bytes. - @param type The type of @c value (URI). - @param flags LV2_State_Flags for @c 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 within - LV2_State_Interface.save() to store all the statements 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 you can make - documentation resolvable. 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. - - Note that @c size MUST be > 0, and @c value MUST point to a valid region of - memory @c 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 int (*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 (predicate) of the property to retrieve (URI). - @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 LV2_State_Flags for - the returned value. - @return A pointer to the restored value (object), or NULL if no value - has been stored under @c key. - - A callback of this type is passed by the host to - LV2_State_Interface.restore(). This callback is called repeatedly by the - plugin within LV2_State_Interface.restore() 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. Returned values - MAY be copied for later use if necessary, assuming the plugin knows how to - do so correctly (e.g. the value is POD, or the plugin understands the type). -*/ -typedef const void* (*LV2_State_Retrieve_Function)(LV2_State_Handle handle, - uint32_t key, - size_t* size, - uint32_t* type, - uint32_t* flags); - -/** - State Extension Data. - - When the plugin's extension_data is called with argument LV2_STATE_URI, - the plugin MUST return an LV2_State 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 - for the given function are met). - - The typical use case is to save the plugin's state when a project is saved, - and to restore the state when a project has been loaded. Other uses are - possible (e.g. cloning plugin instances or taking a snapshot of plugin - state). - - 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 compatibility issues in the future. -*/ -typedef struct _LV2_State_Interface { - - /** - Save plugin state using a host-provided @c 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, e.g. the map or - file where the values are to be stored. If @c store is called, this MUST - be passed as its handle parameter. - @param flags Flags describing desires properties of this save. The - plugin SHOULD use these values to determine the most appropriate and/or - efficient serialisation, but is not required to do so. - @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 (possibly much later, in a different process, on - a completely different machine, etc.) - - The @c handle pointer and @c 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. - */ - void (*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 @c 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, e.g. the map or - file from which the values are to be restored. If @c retrieve is - called, this MUST be passed as its handle parameter. - @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 @c handle pointer and @c 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. - */ - void (*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 (LV2_STATE_MAP_PATH_URI). -*/ -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 @a 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 files in plugin state. The returned value is an abstract path which - MAY not be an actual file system path; @ref absolute_path MUST be used - to map it to an actual path in order to use the file. - - Hosts MAY map paths in any way (e.g. by creating symbolic links within - the plugin's state directory or storing a list of referenced files - elsewhere). Plugins MUST NOT make any assumptions about abstract paths - except that they can be mapped back to an absolute path using @ref - absolute_path. - - This function may only be called within the context of - LV2_State_Interface.save() or LV2_State_Interface.restore(). The caller - is responsible for freeing the returned value. - */ - 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 @a handle member of this struct. - @param abstract_path An abstract path (e.g. a path from plugin state). - @return An absolute file system path. - - Since abstract paths are not necessarily actual file paths (or at least - not necessarily absolute paths), this function MUST be used in order to - actually open or otherwise use the file referred to by an abstract path. - - This function may only be called within the context of - LV2_State_Interface.save() or LV2_State_Interface.restore(). The caller - is responsible for freeing the returned value. - */ - 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_MAKE_PATH_URI). -*/ -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 @a handle member of this struct. - @param path The path of the new file relative to 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/ns/ext/state/state.ttl b/lv2/ns/ext/state/state.ttl deleted file mode 100644 index 6c0656a..0000000 --- a/lv2/ns/ext/state/state.ttl +++ /dev/null @@ -1,359 +0,0 @@ -# LV2 State Extension -# Copyright 2010-2012 David Robillard -# Copyright 2010 Leonard Ritter -# -# 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 dcs: . -@prefix doap: . -@prefix foaf: . -@prefix lv2: . -@prefix rdf: . -@prefix rdfs: . -@prefix state: . - - - a foaf:Person ; - foaf:name "David Robillard" ; - foaf:homepage ; - foaf:mbox ; - rdfs:seeAlso . - - - a lv2:Specification ; - doap:name "LV2 State" ; - doap:shortdesc "An interface for LV2 plugins to save and restore state." ; - doap:license ; - doap:release [ - doap:revision "0.5" ; - doap:created "2012-01-29" ; - dcs:blame - ] ; - doap:developer [ - a foaf:Person ; - foaf:name "Leonard Ritter" ; - foaf:homepage - ] ; - doap:maintainer [ - a foaf:Person ; - foaf:name "David Robillard" ; - foaf:homepage ; - rdfs:seeAlso - ] ; - lv2:documentation """ -

This extension provides a simple mechanism for plugins to save and restore -state across instances, allowing hosts to save and restore a plugin instance's -state at any time. The goal is for an instance's state to be -completely described by port values (as with all LV2 plugins) and a -dictionary.

- -

The state described by this extension is conceptually a simple -key:value dictionary, where keys are URIDs (URIs mapped to integers) and values -are type-tagged blobs of any type. A single key:value pair is called a -property. 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.

- -

This state model is simple yet has many benefits:

-
    -
  • URID keys provide both fast performance and RDF compatibility.
    • -
  • Fully extensible, no limitations on keys or value types.
    • -
  • Easy to serialise in many formats (e.g. any RDF syntax, plain - text, JSON, XML, key:value databases, SQL, s-expressions, etc.).
    • -
  • Elegantly described in Turtle, which is useful for describing presets - or default state in LV2 data files (the predicate state:state is provided - for this purpose).
    • -
  • Does not impose any file formats, data structures, or file system - requirements.
    • -
  • Suitable for portable persistent state as well as fast in-memory - snapshots.
    • -
  • Easily stored in a typical map or dictionary data - structure.
    • -
  • Keys may be defined by extensions and used by several plugins, - making state meaningful enabling dynamic state control.
    • -
- -

Implementations or further extensions which work with plugin state -(including dynamic plugin control) SHOULD work entirely within this model. -That is, do not complicate the state model. All -information required to express an instance's state at any given time can, and -should, be expressed within this model.

- -

Plugin Code Example

- -
-#define NS_EG   "http://example.org/"
-#define NS_ATOM "http://lv2plug.in/ns/ext/atom#"
-
-LV2_Handle my_instantiate(...)
-{
-    MyPlugin* plugin = ...;
-    plugin->uris.atom_String = map_uri(NS_ATOM "String");
-    plugin->uris.eg_greeting = map_uri(NS_EG "greeting");
-    plugin->state.greeting   = strdup("Hello");
-    return plugin;
-}
-
-void my_save(LV2_Handle                 instance,
-             LV2_State_Store_Function   store,
-             void*                      handle,
-             uint32_t                   flags,
-             const LV2_Feature *const * features)
-{
-    MyPlugin*   plugin   = (MyPlugin*)instance;
-    const char* greeting = plugin->state.greeting;
-
-    store(handle,
-          plugin->uris.eg_greeting,
-          greeting,
-          strlen(greeting) + 1,
-          plugin->uris.atom_String,
-          LV2_STATE_IS_POD | LV2_STATE_IS_PORTABLE);
-}
-
-void my_restore(LV2_Handle                  instance,
-                LV2_State_Retrieve_Function retrieve,
-                void*                       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.eg_greeting, &size, &type, &flags);
-
-    if (greeting) {
-        free(plugin->state->greeting);
-        plugin->state->greeting = strdup(greeting);
-    } else {
-        plugin->state->greeting = strdup("Hello");
-    }
-}
-
-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_URI)) {
-        return &state_iface;
-    }
-}
-
- -

Host Code Example

- -
-int store_callback(void*       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.
-           If this was for disk or network storage/transmission,
-           LV2_STATE_IS_PORTABLE would have to be checked as well.
-        */
-        Map* state_map = (Map*)handle;
-        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_State* state = instance.extension_data("http://lv2plug.in/ns/ext/state");
-    Map state_map;
-    /** Request a fast/native/POD save, since we're just copying in memory */
-    state.save(instance, store_callback, &state_map,
-               LV2_STATE_IS_POD|LV2_STATE_IS_NATIVE);
-    return state_map;
-}
-
- -

Referring to Existing Files

- -

Plugins may need to refer to 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.

- -

Creating New Files or Directories

- -

Implementations are strongly encouraged to avoid the use of files and simply -store all state as properties whenever possible. However, occasionally the -ability to create files is necessary. The feature state:newPath makes this possible, if it is provided by the -host.

-""" . - -state:Interface - a rdfs:Class ; - rdfs:subClassOf lv2:ExtensionData ; - 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 -LV2_STATE_INTERFACE_URI.

- -

The plugin data file should describe this like so:

-
-@prefix state: <http://lv2plug.in/ns/ext/state#> .
-
-<plugin>
-    a lv2:Plugin ;
-    lv2:extensionData state:Interface .
-
-""" . - -state:State - a rdfs:Class ; - rdfs:label "Plugin Instance State" ; - lv2:documentation """ -

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 state:State as the subject (see state:state 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 State -extension.

-""" . - -state:state - a rdf:Property ; - rdfs:range state:State ; - lv2:documentation """ -

Predicate to relate a plugin instance to its State. 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.:

-
-@prefix eg: <http://example.org/> .
-
-<plugininstance>
-    state:state [
-        eg:somekey "some value" ;
-        eg:someotherkey "some other value" ;
-        eg:favourite-number 2
-    ] .
-
-

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 this extension.

-""" . - -state:mapPath - a lv2:Feature ; - rdfs:label "Support for storing paths in files" ; - lv2:documentation """ - -

This feature maps absolute paths to/from abstract paths which are -stored in state. To support this feature a host must pass an LV2_Feature with -URI LV2_STATE_MAP_PATH_URI 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 in any -files in its state). This is necessary to enable host to handle file system -references correctly, e.g. for distribution or archival.

- -

For example, a plugin may write a path to a state file like so:

- -
-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:

- -
-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);
-}
-
-""" . - -state:makePath - a lv2:Feature ; - rdfs:label "Support for creating new files and directories" ; - 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_MAKE_PATH_URI 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 hierarchial 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, -i.e. 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:

- -
-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, "Hello");
-    fclose(myfile);
-    return path;
-}
-
-""" . - -state:Path - a rdfs:Class ; - rdfs:label "Path" ; - lv2:documentation """ -

A path to a file or directory.

- -

The format of a state:Path is a C string, possibly escaped or otherwise -restricted in a system-specific manner. This URI (LV2_STATE_PATH_URI), mapped -to an integer, MUST be used as the type parameter for any files -passed to the LV2_State_Store_Function; and will likewise be returned by the -corresponding call to the LV2_State_Retrieve_Function.

- -

When storing and retrieving a path, the plugin MUST NOT assume the same path -will be restored. However, the restored path will refer to a file with -equivalent contents to the original.

-""" . diff --git a/lv2/ns/ext/state/waf b/lv2/ns/ext/state/waf deleted file mode 120000 index b955110..0000000 --- a/lv2/ns/ext/state/waf +++ /dev/null @@ -1 +0,0 @@ -../../../../waf \ No newline at end of file diff --git a/lv2/ns/ext/state/wscript b/lv2/ns/ext/state/wscript deleted file mode 120000 index ec20a77..0000000 --- a/lv2/ns/ext/state/wscript +++ /dev/null @@ -1 +0,0 @@ -../../../../ext.wscript \ No newline at end of file -- cgit v1.2.1