1 /* 2 Copyright 2008-2012 David Robillard <http://drobilla.net> 3 Copyright 2011 Gabriel M. Beddingfield <gabrbedd@gmail.com> 4 5 Permission to use, copy, modify, and/or distribute this software for any 6 purpose with or without fee is hereby granted, provided that the above 7 copyright notice and this permission notice appear in all copies. 8 9 THIS SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES 10 WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF 11 MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR 12 ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES 13 WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN 14 ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF 15 OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE. 16 */ 17 18 /** 19 @file urid.h 20 C header for the LV2 URID extension <http://lv2plug.in/ns/ext/urid> 21 */ 22 23 #ifndef LV2_URID_H 24 #define LV2_URID_H 25 26 #define LV2_URID_URI "http://lv2plug.in/ns/ext/urid" 27 #define LV2_URID_PREFIX LV2_URID_URI "#" 28 29 #define LV2_URID__map LV2_URID_PREFIX "map" 30 #define LV2_URID__unmap LV2_URID_PREFIX "unmap" 31 32 /* Legacy defines */ 33 #define LV2_URID_MAP_URI LV2_URID__map 34 #define LV2_URID_UNMAP_URI LV2_URID__unmap 35 36 #include <stdint.h> 37 38 #ifdef __cplusplus 39 extern "C" { 40 #endif 41 42 /** 43 Opaque pointer to host data for LV2_URID_Map. 44 */ 45 typedef void* LV2_URID_Map_Handle; 46 47 /** 48 Opaque pointer to host data for LV2_URID_Unmap. 49 */ 50 typedef void* LV2_URID_Unmap_Handle; 51 52 /** 53 URI mapped to an integer. 54 */ 55 typedef uint32_t LV2_URID; 56 57 /** 58 URID Map Feature (LV2_URID__map) 59 */ 60 typedef struct _LV2_URID_Map { 61 /** 62 Opaque pointer to host data. 63 64 This MUST be passed to map_uri() whenever it is called. 65 Otherwise, it must not be interpreted in any way. 66 */ 67 LV2_URID_Map_Handle handle; 68 69 /** 70 Get the numeric ID of a URI. 71 72 If the ID does not already exist, it will be created. 73 74 This function is referentially transparent; any number of calls with the 75 same arguments is guaranteed to return the same value over the life of a 76 plugin instance. Note, however, that several URIs MAY resolve to the 77 same ID if the host considers those URIs equivalent. 78 79 This function is not necessarily very fast or RT-safe: plugins SHOULD 80 cache any IDs they might need in performance critical situations. 81 82 The return value 0 is reserved and indicates that an ID for that URI 83 could not be created for whatever reason. However, hosts SHOULD NOT 84 return 0 from this function in non-exceptional circumstances (i.e. the 85 URI map SHOULD be dynamic). 86 87 @param handle Must be the callback_data member of this struct. 88 @param uri The URI to be mapped to an integer ID. 89 */ 90 LV2_URID (*map)(LV2_URID_Map_Handle handle, 91 const char* uri); 92 } LV2_URID_Map; 93 94 /** 95 URI Unmap Feature (LV2_URID__unmap) 96 */ 97 typedef struct _LV2_URID_Unmap { 98 /** 99 Opaque pointer to host data. 100 101 This MUST be passed to unmap() whenever it is called. 102 Otherwise, it must not be interpreted in any way. 103 */ 104 LV2_URID_Unmap_Handle handle; 105 106 /** 107 Get the URI for a previously mapped numeric ID. 108 109 Returns NULL if @p urid is not yet mapped. Otherwise, the corresponding 110 URI is returned in a canonical form. This MAY not be the exact same 111 string that was originally passed to LV2_URID_Map::map(), but it MUST be 112 an identical URI according to the URI syntax specification (RFC3986). A 113 non-NULL return for a given @p urid will always be the same for the life 114 of the plugin. Plugins that intend to perform string comparison on 115 unmapped URIs SHOULD first canonicalise URI strings with a call to 116 map_uri() followed by a call to unmap_uri(). 117 118 @param handle Must be the callback_data member of this struct. 119 @param urid The ID to be mapped back to the URI string. 120 */ 121 const char* (*unmap)(LV2_URID_Unmap_Handle handle, 122 LV2_URID urid); 123 } LV2_URID_Unmap; 124 125 #ifdef __cplusplus 126 } /* extern "C" */ 127 #endif 128 129 #endif /* LV2_URID_H */ 130