Fix cut and past error in ast_call_forward().
[asterisk/asterisk.git] / bridges / bridge_simple.c
1 /*
2  * Asterisk -- An open source telephony toolkit.
3  *
4  * Copyright (C) 2007, Digium, Inc.
5  *
6  * Joshua Colp <jcolp@digium.com>
7  *
8  * See http://www.asterisk.org for more information about
9  * the Asterisk project. Please do not directly contact
10  * any of the maintainers of this project for assistance;
11  * the project provides a web site, mailing lists and IRC
12  * channels for your use.
13  *
14  * This program is free software, distributed under the terms of
15  * the GNU General Public License Version 2. See the LICENSE file
16  * at the top of the source tree.
17  */
18
19 /*! \file
20  *
21  * \brief Simple two channel bridging module
22  *
23  * \author Joshua Colp <jcolp@digium.com>
24  *
25  * \ingroup bridges
26  */
27
28 /*** MODULEINFO
29         <support_level>core</support_level>
30  ***/
31
32 #include "asterisk.h"
33
34 ASTERISK_FILE_VERSION(__FILE__, "$Revision$")
35
36 #include <stdio.h>
37 #include <stdlib.h>
38 #include <string.h>
39 #include <sys/types.h>
40 #include <sys/stat.h>
41
42 #include "asterisk/module.h"
43 #include "asterisk/channel.h"
44 #include "asterisk/bridging.h"
45 #include "asterisk/bridging_technology.h"
46 #include "asterisk/frame.h"
47
48 static int simple_bridge_join(struct ast_bridge *bridge, struct ast_bridge_channel *bridge_channel)
49 {
50         struct ast_channel *c0 = AST_LIST_FIRST(&bridge->channels)->chan, *c1 = AST_LIST_LAST(&bridge->channels)->chan;
51
52         /* If this is the first channel we can't make it compatible... unless we make it compatible with itself O.o */
53         if (AST_LIST_FIRST(&bridge->channels) == AST_LIST_LAST(&bridge->channels)) {
54                 return 0;
55         }
56
57         /* See if we need to make these compatible */
58         if ((ast_format_cmp(&c0->writeformat, &c1->readformat) == AST_FORMAT_CMP_EQUAL) &&
59                 (ast_format_cmp(&c0->readformat, &c1->writeformat) == AST_FORMAT_CMP_EQUAL) &&
60                 (ast_format_cap_identical(c0->nativeformats, c1->nativeformats))) {
61                 return 0;
62         }
63
64         /* BOOM! We do. */
65         return ast_channel_make_compatible(c0, c1);
66 }
67
68 static enum ast_bridge_write_result simple_bridge_write(struct ast_bridge *bridge, struct ast_bridge_channel *bridge_channel, struct ast_frame *frame)
69 {
70         struct ast_bridge_channel *other = NULL;
71
72         /* If this is the only channel in this bridge then immediately exit */
73         if (AST_LIST_FIRST(&bridge->channels) == AST_LIST_LAST(&bridge->channels)) {
74                 return AST_BRIDGE_WRITE_FAILED;
75         }
76
77         /* Find the channel we actually want to write to */
78         if (!(other = (AST_LIST_FIRST(&bridge->channels) == bridge_channel ? AST_LIST_LAST(&bridge->channels) : AST_LIST_FIRST(&bridge->channels)))) {
79                 return AST_BRIDGE_WRITE_FAILED;
80         }
81
82         /* Write the frame out if they are in the waiting state... don't worry about freeing it, the bridging core will take care of it */
83         if (other->state == AST_BRIDGE_CHANNEL_STATE_WAIT) {
84                 ast_write(other->chan, frame);
85         }
86
87         return AST_BRIDGE_WRITE_SUCCESS;
88 }
89
90 static struct ast_bridge_technology simple_bridge = {
91         .name = "simple_bridge",
92         .capabilities = AST_BRIDGE_CAPABILITY_1TO1MIX | AST_BRIDGE_CAPABILITY_THREAD,
93         .preference = AST_BRIDGE_PREFERENCE_MEDIUM,
94         .join = simple_bridge_join,
95         .write = simple_bridge_write,
96 };
97
98 static int unload_module(void)
99 {
100         ast_format_cap_destroy(simple_bridge.format_capabilities);
101         return ast_bridge_technology_unregister(&simple_bridge);
102 }
103
104 static int load_module(void)
105 {
106         if (!(simple_bridge.format_capabilities = ast_format_cap_alloc())) {
107                 return AST_MODULE_LOAD_DECLINE;
108         }
109         ast_format_cap_add_all_by_type(simple_bridge.format_capabilities, AST_FORMAT_TYPE_AUDIO);
110         ast_format_cap_add_all_by_type(simple_bridge.format_capabilities, AST_FORMAT_TYPE_VIDEO);
111         ast_format_cap_add_all_by_type(simple_bridge.format_capabilities, AST_FORMAT_TYPE_TEXT);
112
113         return ast_bridge_technology_register(&simple_bridge);
114 }
115
116 AST_MODULE_INFO_STANDARD(ASTERISK_GPL_KEY, "Simple two channel bridging module");