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-rw-r--r--lv2/state/state.h441
1 files changed, 220 insertions, 221 deletions
diff --git a/lv2/state/state.h b/lv2/state/state.h
index 0de3ee4..55db43b 100644
--- a/lv2/state/state.h
+++ b/lv2/state/state.h
@@ -55,10 +55,13 @@
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
+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.
@@ -67,52 +70,52 @@ typedef void* LV2_State_Make_Path_Handle; ///< Opaque handle for state:makePath
(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 (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 = 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 (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 = 1 << 2
+ /**
+ 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 (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 = 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 (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 = 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_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;
/**
@@ -148,13 +151,12 @@ typedef enum {
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);
+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.
@@ -174,12 +176,11 @@ typedef LV2_State_Status (*LV2_State_Store_Function)(
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);
+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.
@@ -200,186 +201,184 @@ typedef const void* (*LV2_State_Retrieve_Function)(
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);
+ /**
+ 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);
+ /**
+ 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);
+ /**
+ 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);
+ /**
+ 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