dplug.lv2.options source code

1 /*
2   Copyright 2012-2016 David Robillard <http://drobilla.net>
3   Copyright 2018 Ethan Reker <http://cutthroughrecordings.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    @defgroup options Options
20 
21    Instantiation time options, see <http://lv2plug.in/ns/ext/options> for
22    details.
23 
24    @{
25 */
26 module dplug.lv2.options;
27 
28 version(LV2):
29 
30 import core.stdc.stdint;
31 
32 import dplug.lv2.urid;
33 import dplug.lv2.lv2;
34 
35 enum LV2_OPTIONS_URI = "http://lv2plug.in/ns/ext/options";  ///< http://lv2plug.in/ns/ext/options
36 enum LV2_OPTIONS_PREFIX = LV2_OPTIONS_URI ~ "#";                 ///< http://lv2plug.in/ns/ext/options#
37 
38 enum LV2_OPTIONS__Option          = LV2_OPTIONS_PREFIX ~ "Option";           ///< http://lv2plug.in/ns/ext/options#Option
39 enum LV2_OPTIONS__interface       = LV2_OPTIONS_PREFIX ~ "interface";        ///< http://lv2plug.in/ns/ext/options#interface
40 enum LV2_OPTIONS__options         = LV2_OPTIONS_PREFIX ~ "options";          ///< http://lv2plug.in/ns/ext/options#options
41 enum LV2_OPTIONS__requiredOption  = LV2_OPTIONS_PREFIX ~ "requiredOption";   ///< http://lv2plug.in/ns/ext/options#requiredOption
42 enum LV2_OPTIONS__supportedOption = LV2_OPTIONS_PREFIX ~ "supportedOption";  ///< http://lv2plug.in/ns/ext/options#supportedOption
43 
44 /**
45 The context of an Option, which defines the subject it applies to.
46 */
47 alias LV2_Options_Context = int;
48 enum : int 
49 {
50     /**
51     This option applies to the instance itself.  The subject must be
52     ignored.
53     */
54     LV2_OPTIONS_INSTANCE,
55 
56     /**
57     This option applies to some named resource.  The subject is a URI mapped
58     to an integer (a LV2_URID, like the key)
59     */
60     LV2_OPTIONS_RESOURCE,
61 
62     /**
63     This option applies to some blank node.  The subject is a blank node
64     identifier, which is valid only within the current local scope.
65     */
66     LV2_OPTIONS_BLANK,
67 
68     /**
69     This option applies to a port on the instance.  The subject is the
70     port's index.
71     */
72     LV2_OPTIONS_PORT
73 }
74 
75 /**
76 An option.
77 
78 This is a property with a subject, also known as a triple or statement.
79 
80 This struct is useful anywhere a statement needs to be passed where no
81 memory ownership issues are present (since the value is a const pointer).
82 
83 Options can be passed to an instance via the feature LV2_OPTIONS__options
84 with data pointed to an array of options terminated by a zeroed option, or
85 accessed/manipulated using LV2_Options_Interface.
86 */
87 struct LV2_Options_Option 
88 {
89     LV2_Options_Context context;  /**< Context (type of subject). */
90     uint32_t            subject;  /**< Subject. */
91     LV2_URID            key;      /**< Key (property). */
92     uint32_t            size;     /**< Size of value in bytes. */
93     LV2_URID            type;     /**< Type of value (datatype). */
94     const void*         value;    /**< Pointer to value (object). */
95 }
96 
97 /** A status code for option functions. */
98 alias LV2_Options_Status = int;
99 enum : int {
100     LV2_OPTIONS_SUCCESS         = 0,       /**< Completed successfully. */
101     LV2_OPTIONS_ERR_UNKNOWN     = 1,       /**< Unknown error. */
102     LV2_OPTIONS_ERR_BAD_SUBJECT = 1 << 1,  /**< Invalid/unsupported subject. */
103     LV2_OPTIONS_ERR_BAD_KEY     = 1 << 2,  /**< Invalid/unsupported key. */
104     LV2_OPTIONS_ERR_BAD_VALUE   = 1 << 3   /**< Invalid/unsupported value. */
105 }
106 
107 /**
108 Interface for dynamically setting options (LV2_OPTIONS__interface).
109 */
110 struct LV2_Options_Interface 
111 {
112 nothrow:
113 @nogc:
114 extern(C):
115     /**
116     Get the given options.
117 
118     Each element of the passed options array MUST have type, subject, and
119     key set.  All other fields (size, type, value) MUST be initialised to
120     zero, and are set to the option value if such an option is found.
121 
122     This function is in the "instantiation" LV2 threading class, so no other
123     instance functions may be called concurrently.
124 
125     @return Bitwise OR of LV2_Options_Status values.
126     */
127     uint32_t function(LV2_Handle          instance,
128                     LV2_Options_Option* options) get;
129 
130     /**
131     Set the given options.
132 
133     This function is in the "instantiation" LV2 threading class, so no other
134     instance functions may be called concurrently.
135 
136     @return Bitwise OR of LV2_Options_Status values.
137     */
138     uint32_t function(LV2_Handle instance, const(LV2_Options_Option)* options) set;
139 }