20dd9b86f70970b8d178605f46e2467a728352ef
[paraslash.git] / recv.h
1 /*
2 * Copyright (C) 2005-2009 Andre Noll <maan@systemlinux.org>
3 *
4 * Licensed under the GPL v2. For licencing details see COPYING.
5 */
6
7 /** \file recv.h Receiver-related structures and exported symbols of recv_common.c. */
8
9 /**
10 * Describes one instance of a receiver.
11 */
12 struct receiver_node {
13 /** Points to the corresponding receiver. */
14 struct receiver *receiver;
15 /** The output buffer. */
16 char *buf;
17 /** The amount of bytes in \a buf. */
18 size_t loaded;
19 /** Receiver-specific data. */
20 void *private_data;
21 /** Pointer to the error member of the consumer. */
22 int *output_error;
23 /** Pointer to the configuration data for this instance. */
24 void *conf;
25 /** The task associated with this instance. */
26 struct task task;
27 /** The receiver node is always the root of the buffer tree. */
28 struct btr_node *btrn;
29 };
30
31 /**
32 * Describes one supported paraslash receiver.
33 *
34 * \sa http_recv.c, udp_recv.c
35 */
36 struct receiver {
37 /**
38 * The name of the receiver.
39 */
40 const char *name;
41 /**
42 * The receiver init function.
43 *
44 * It must fill in all other function pointers and is assumed to succeed.
45 *
46 * \sa http_recv_init udp_recv_init.
47 */
48 void (*init)(struct receiver *r);
49 /**
50 * The command line parser of the receiver.
51 *
52 * It should check whether the command line options given by \a argc and \a
53 * argv are valid. On success, it should return a pointer to the
54 * receiver-specific configuration data determined by \a argc and \a argv.
55 * Note that this might be called more than once with different values of
56 * \a argc and \a argv.
57 */
58 void *(*parse_config)(int argc, char **argv);
59 void (*free_config)(void *conf);
60 /**
61 * Open one instance of the receiver.
62 *
63 * This should allocate the output buffer of \a rn. and may also
64 * perform any other work necessary for retrieving the stream according
65 * to the configuration stored in the \a conf member of \a rn which is
66 * guaranteed to point to valid configuration data (as previously
67 * obtained from the config parser).
68 *
69 * \sa receiver_node::conf, receiver_node::buf.
70 */
71 int (*open)(struct receiver_node *rn);
72 /**
73 * Close this instance of the receiver.
74 *
75 * It should free all resources associated with given receiver node
76 * that were allocated during the corresponding open call.
77 *
78 * \sa receiver_node.
79 */
80 void (*close)(struct receiver_node *rn);
81 /**
82 * Add file descriptors to fd_sets and compute timeout for select(2).
83 *
84 * The pre_select function gets called from the driving application
85 * before entering its select loop. The receiver may use this hook to
86 * add any file descriptors to the sets of file descriptors given by \a
87 * s.
88 *
89 * \sa select(2), time.c struct task, struct sched.
90 */
91 void (*pre_select)(struct sched *s, struct task *t);
92 /**
93 * Evaluate the result from select().
94 *
95 * This hook gets called after the call to select(). It should check
96 * all file descriptors which were added to any of the the fd sets
97 * during the previous call to pre_select. According to the result, it
98 * may then use any non-blocking I/O to establish a connection or to
99 * receive the audio data.
100 *
101 * \sa select(2), struct receiver.
102 */
103 void (*post_select)(struct sched *s, struct task *t);
104
105 /** The two help texts of this receiver. */
106 struct ggo_help help;
107 };
108
109
110 /** \cond */
111 extern void http_recv_init(struct receiver *r);
112 #define HTTP_RECEIVER {.name = "http", .init = http_recv_init},
113 extern void dccp_recv_init(struct receiver *r);
114 #define DCCP_RECEIVER {.name = "dccp", .init = dccp_recv_init},
115 extern void udp_recv_init(struct receiver *r);
116 #define UDP_RECEIVER {.name = "udp", .init = udp_recv_init},
117
118 extern struct receiver receivers[];
119 /** \endcond */
120
121 /** Define an array of all available receivers. */
122 #define DEFINE_RECEIVER_ARRAY struct receiver receivers[] = { \
123 HTTP_RECEIVER \
124 DCCP_RECEIVER \
125 UDP_RECEIVER \
126 {.name = NULL}};
127
128 /** Iterate over all available receivers. */
129 #define FOR_EACH_RECEIVER(i) for (i = 0; receivers[i].name; i++)
130
131 void recv_init(void);
132 void *check_receiver_arg(char *ra, int *receiver_num);
133 void print_receiver_helps(int detailed);
134 int generic_recv_pre_select(struct sched *s, struct task *t);