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/*
  Copyright 2011 Gabriel M. Beddingfield <gabrbedd@gmail.com>
  Copyright 2008-2011 David Robillard <http://drobilla.net>

  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 header for the LV2 URID extension <http://lv2plug.in/ns/ext/urid>
*/

#ifndef LV2_URID_H
#define LV2_URID_H

#define LV2_URID_URI "http://lv2plug.in/ns/ext/urid"

#include <stdint.h>

/**
   Opaque pointer to host data for LV2_URID_Mapper.
*/
typedef void* LV2_URID_Mapper_Handle;

/**
   Opaque pointer to host data for LV2_URID_Unmapper.
*/
typedef void* LV2_URID_Unmapper_Handle;

/**
   URI mapped to an integer.
*/
typedef uint32_t LV2_URID;

/**
   URI Mapper (http://lv2plug.in/ns/ext/urid#Mapper).
*/
typedef struct {
	/**
	   Opaque pointer to host data.

	   This MUST be passed to map_uri() whenever it is called.
	   Otherwise, it must not be interpreted in any way.
	*/
	LV2_URID_Mapper_Handle handle;

	/**
	   Get the numeric ID of a URI.

	   If the ID does not already exist, it will be created.

	   This function is referentially transparent; any number of calls with the
	   same arguments is guaranteed to return the same value over the life of a
	   plugin instance.  However, this function is not necessarily very
	   fast or RT-safe: plugins SHOULD cache any IDs they might need in
	   performance critical situations.

	   The return value 0 is reserved and indicates that an ID for that URI
	   could not be created for whatever reason.  However, hosts SHOULD NOT
	   return 0 from this function in non-exceptional circumstances (i.e. the
	   URI map SHOULD be dynamic).

	   @param handle Must be the callback_data member of this struct.
	   @param uri The URI to be mapped to an integer ID.
	*/
	LV2_URID (*map_uri)(LV2_URID_Mapper_Handle handle,
	                    const char*            uri);
} LV2_URID_Mapper;

/**
   URI Unmapper (http://lv2plug.in/ns/ext/urid#Unmapper).
*/
typedef struct {
	/**
	   Opaque pointer to host data.

	   This MUST be passed to unmap_uri() whenever it is called.
	   Otherwise, it must not be interpreted in any way.
	*/
	LV2_URID_Unmapper_Handle handle;

	/**
	   Get the URI for a previously mapped numeric ID.

	   Returns NULL if @c urid is not yet mapped.  Otherwise, the corresponding
	   URI is returned in a canonical form.  This MAY not be the exact same
	   string that was originally passed to map_uri(), but it MUST be an
	   identical URI according to the URI spec.  A non-NULL return for a given
	   @c urid will always be the same for the life of the plugin.  Plugins
	   that intend to perform string comparison on unmapped URIs SHOULD first
	   canonicalise URI strings with a call to map_uri() followed by a call to
	   unmap_uri().

	   @param handle Must be the callback_data member of this struct.
	   @param urid The ID to be mapped back to the URI string.
	*/
	const char* (*unmap_uri)(LV2_URID_Unmapper_Handle handle,
	                         LV2_URID                 urid);
} LV2_URID_Unmapper;

#endif /* LV2_URID_H */