1 /* PipeWire
2  *
3  * Copyright © 2018 Wim Taymans
4  *
5  * Permission is hereby granted, free of charge, to any person obtaining a
6  * copy of this software and associated documentation files (the "Software"),
7  * to deal in the Software without restriction, including without limitation
8  * the rights to use, copy, modify, merge, publish, distribute, sublicense,
9  * and/or sell copies of the Software, and to permit persons to whom the
10  * Software is furnished to do so, subject to the following conditions:
11  *
12  * The above copyright notice and this permission notice (including the next
13  * paragraph) shall be included in all copies or substantial portions of the
14  * Software.
15  *
16  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
17  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
18  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
19  * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
20  * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
21  * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
22  * DEALINGS IN THE SOFTWARE.
23  */
24 
25 #ifndef PIPEWIRE_IMPL_LINK_H
26 #define PIPEWIRE_IMPL_LINK_H
27 
28 #ifdef __cplusplus
29 extern "C" {
30 #endif
31 
32 /** \class pw_impl_link
33  *
34  * PipeWire link object.
35  */
36 struct pw_impl_link;
37 struct pw_impl_port;
38 
39 #include <pipewire/impl.h>
40 
41 /** \page page_link Link
42  *
43  * \section page_link_overview Overview
44  *
45  * A link is the connection between 2 nodes (\ref page_node). Nodes are
46  * linked together on ports.
47  *
48  * The link is responsible for negotiating the format and buffers for
49  * the nodes.
50  */
51 
52 /** link events added with \ref pw_impl_link_add_listener */
53 struct pw_impl_link_events {
54 #define PW_VERSION_IMPL_LINK_EVENTS	0
55 	uint32_t version;
56 
57 	/** A link is destroyed */
58 	void (*destroy) (void *data);
59 
60 	/** A link is freed */
61 	void (*free) (void *data);
62 
63 	/** a Link is initialized */
64 	void (*initialized) (void *data);
65 
66 	/** The info changed on a link */
67 	void (*info_changed) (void *data, const struct pw_link_info *info);
68 
69 	/** The link state changed, \a error is only valid when the state is
70 	  * in error. */
71 	void (*state_changed) (void *data, enum pw_link_state old,
72 					   enum pw_link_state state, const char *error);
73 
74 	/** A port is unlinked */
75 	void (*port_unlinked) (void *data, struct pw_impl_port *port);
76 };
77 
78 
79 /** Make a new link between two ports \memberof pw_impl_link
80  * \return a newly allocated link */
81 struct pw_impl_link *
82 pw_context_create_link(struct pw_context *context,		/**< the context object */
83 	    struct pw_impl_port *output,		/**< an output port */
84 	    struct pw_impl_port *input,		/**< an input port */
85 	    struct spa_pod *format_filter,	/**< an optional format filter */
86 	    struct pw_properties *properties	/**< extra properties */,
87 	    size_t user_data_size		/**< extra user data size */);
88 
89 /** Destroy a link \memberof pw_impl_link */
90 void pw_impl_link_destroy(struct pw_impl_link *link);
91 
92 /** Add an event listener to \a link */
93 void pw_impl_link_add_listener(struct pw_impl_link *link,
94 			  struct spa_hook *listener,
95 			  const struct pw_impl_link_events *events,
96 			  void *data);
97 
98 /** Finish link configuration and register */
99 int pw_impl_link_register(struct pw_impl_link *link,		/**< the link to register */
100 		     struct pw_properties *properties	/**< extra properties */);
101 
102 /** Get the context of a link */
103 struct pw_context *pw_impl_link_get_context(struct pw_impl_link *link);
104 
105 /** Get the user_data of a link, the size of the memory is given when
106   * constructing the link */
107 void *pw_impl_link_get_user_data(struct pw_impl_link *link);
108 
109 /** Get the link info */
110 const struct pw_link_info *pw_impl_link_get_info(struct pw_impl_link *link);
111 
112 /** Get the global of the link */
113 struct pw_global *pw_impl_link_get_global(struct pw_impl_link *link);
114 
115 /** Get the output port of the link */
116 struct pw_impl_port *pw_impl_link_get_output(struct pw_impl_link *link);
117 
118 /** Get the input port of the link */
119 struct pw_impl_port *pw_impl_link_get_input(struct pw_impl_link *link);
120 
121 /** Find the link between 2 ports \memberof pw_impl_link */
122 struct pw_impl_link *pw_impl_link_find(struct pw_impl_port *output, struct pw_impl_port *input);
123 
124 #ifdef __cplusplus
125 }
126 #endif
127 
128 #endif /* PIPEWIRE_IMPL_LINK_H */
129