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authorBent Bisballe Nyeng <deva@aasimon.org>2012-06-11 19:15:09 +0200
committerBent Bisballe Nyeng <deva@aasimon.org>2012-06-11 19:15:09 +0200
commitfa10bccb322dedee6b72d6f8c1834de8b194d3ca (patch)
treee3ffaecb550be05abc3eabb3ac812d75e351e17d /lv2/lv2_persist.h
parent30d7235c2ceda6d549438a9204b60a0e1f9186de (diff)
Port to new LV2 state interface. Use new lv2-1.0 header files (from system) and remove local copies of same.
Diffstat (limited to 'lv2/lv2_persist.h')
-rw-r--r--lv2/lv2_persist.h231
1 files changed, 0 insertions, 231 deletions
diff --git a/lv2/lv2_persist.h b/lv2/lv2_persist.h
deleted file mode 100644
index 69f1181..0000000
--- a/lv2/lv2_persist.h
+++ /dev/null
@@ -1,231 +0,0 @@
-/*
- Copyright 2010-2011 David Robillard <http://drobilla.net>
- Copyright 2010 Leonard Ritter <paniq@paniq.org>
-
- This header is free software; you can redistribute it and/or modify it
- under the terms of the GNU Lesser General Public License as published
- by the Free Software Foundation; either version 2 of the License, or
- (at your option) any later version.
-
- This header is distributed in the hope that it will be useful, but WITHOUT
- ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
- FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public
- License for more details.
-
- You should have received a copy of the GNU Lesser General Public License
- along with this header; if not, write to the Free Software Foundation,
- Inc., 59 Temple Place, Suite 330, Boston, MA 01222-1307 USA
-*/
-
-/**
- @file
- C API for the LV2 Persist extension <http://lv2plug.in/ns/ext/persist>.
-*/
-
-#ifndef LV2_PERSIST_H
-#define LV2_PERSIST_H
-
-#include <stdbool.h>
-#include <stddef.h>
-#include <stdint.h>
-
-#include "lv2/lv2plug.in/ns/lv2core/lv2.h"
-
-#ifdef __cplusplus
-extern "C" {
-#endif
-
-#define LV2_PERSIST_URI "http://lv2plug.in/ns/ext/persist"
-
-/**
- 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_PERSIST_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_PERSIST_IS_PORTABLE = 1 << 1
-
-} LV2_Persist_Flags;
-
-/**
- A host-provided function to store a property.
- @param callback_data Must be the callback_data passed to LV2_Persist.save().
- @param key The key (predicate) to store @a value under (URI mapped integer).
- @param value Pointer to the value (object) to be stored.
- @param size The size of the data at @a value in bytes.
- @param type The type of @a value (URI).
- @param flags LV2_Persist_Flags for @a value.
- @return 0 on success, otherwise a non-zero error code.
-
- The host passes a callback of this type to LV2_Persist.save(). This callback
- is called repeatedly by the plugin within LV2_Persist.save() to store all
- the statements that describe its current state.
-
- The host MAY fail to store a property if the type is not understood and is
- not LV2_PERSIST_IS_POD and/or LV2_PERSIST_IS_PORTABLE. Implementations are
- encouraged to use POD and portable values (e.g. string literals) wherever
- possible, and use common types (e.g. types from
- http://lv2plug.in/ns/ext/atom) regardless, since hosts are likely to already
- contain the necessary implementation.
-
- Note that @a size MUST be > 0, and @a value MUST point to a valid region of
- memory @a size bytes long (this is required to make restore unambiguous).
-
- The plugin MUST NOT attempt to use this function outside of the
- LV2_Persist.restore() context.
-*/
-typedef int (*LV2_Persist_Store_Function)(
- void* callback_data,
- uint32_t key,
- const void* value,
- size_t size,
- uint32_t type,
- uint32_t flags);
-
-/**
- A host-provided function to retrieve a property.
- @param callback_data Must be the callback_data passed to LV2_Persist.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_Persist_Flags for
- the returned value.
- @return A pointer to the restored value (object), or NULL if no value
- has been stored under @a key.
-
- A callback of this type is passed by the host to LV2_Persist.restore(). This
- callback is called repeatedly by the plugin within LV2_Persist.restore() to
- retrieve any properties it requires to restore its state.
-
- The returned value MUST remain valid until LV2_Persist.restore() returns.
-
- The plugin MUST NOT attempt to use this function, or any value returned from
- it, outside of the LV2_Persist.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_Persist_Retrieve_Function)(
- void* callback_data,
- uint32_t key,
- size_t* size,
- uint32_t* type,
- uint32_t* flags);
-
-/**
- Persist Extension Data.
-
- When the plugin's extension_data is called with argument LV2_PERSIST_URI,
- the plugin MUST return an LV2_Persist 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_Persist {
-
- /**
- Save plugin state using a host-provided @a store callback.
-
- @param instance The instance handle of the plugin.
- @param store The host-provided store callback.
- @param callback_data An opaque pointer to host data, e.g. the map or
- file where the values are to be stored. If @a store is called,
- this MUST be passed as its callback_data parameter.
-
- 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 @a callback_data pointer and @a 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_Persist_Store_Function store,
- void* callback_data);
-
- /**
- Restore plugin state using a host-provided @a retrieve callback.
-
- @param instance The instance handle of the plugin.
- @param retrieve The host-provided retrieve callback.
- @param callback_data An opaque pointer to host data, e.g. the map or
- file from which the values are to be restored. If @a retrieve is
- called, this MUST be passed as its callback_data parameter.
-
- The plugin MAY assume a restored value was set by a previous call to
- LV2_Persist.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 @a callback_data pointer and @a 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_Persist_Retrieve_Function retrieve,
- void* callback_data);
-
-} LV2_Persist;
-
-#ifdef __cplusplus
-} /* extern "C" */
-#endif
-
-#endif /* LV2_PERSIST_H */