mp3dec: Fix possible endless loop.
[paraslash.git] / recv.h
1 /*
2 * Copyright (C) 2005-2011 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 /** Receiver-specific data. */
16 void *private_data;
17 /** Pointer to the configuration data for this instance. */
18 void *conf;
19 /** The task associated with this instance. */
20 struct task task;
21 /** The receiver node is always the root of the buffer tree. */
22 struct btr_node *btrn;
23 };
24
25 /**
26 * Describes one supported paraslash receiver.
27 *
28 * \sa http_recv.c, udp_recv.c
29 */
30 struct receiver {
31 /**
32 * The name of the receiver.
33 */
34 const char *name;
35 /**
36 * The receiver init function.
37 *
38 * It must fill in all other function pointers and is assumed to succeed.
39 *
40 * \sa http_recv_init udp_recv_init.
41 */
42 void (*init)(struct receiver *r);
43 /**
44 * The command line parser of the receiver.
45 *
46 * It should check whether the command line options given by \a argc and \a
47 * argv are valid. On success, it should return a pointer to the
48 * receiver-specific configuration data determined by \a argc and \a argv.
49 * Note that this might be called more than once with different values of
50 * \a argc and \a argv.
51 */
52 void *(*parse_config)(int argc, char **argv);
53 /**
54 * Deallocate the configuration structure of a receiver node.
55 *
56 * This calls the receiver-specific cleanup function generated by
57 * gengetopt.
58 */
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 /** Define an array of all available receivers. */
110 #define DEFINE_RECEIVER_ARRAY struct receiver receivers[] = { \
111 HTTP_RECEIVER \
112 DCCP_RECEIVER \
113 UDP_RECEIVER \
114 {.name = NULL}};
115
116 /** Iterate over all available receivers. */
117 #define FOR_EACH_RECEIVER(i) for (i = 0; receivers[i].name; i++)
118
119 void recv_init(void);
120 void *check_receiver_arg(char *ra, int *receiver_num);
121 void print_receiver_helps(int detailed);
122 int generic_recv_pre_select(struct sched *s, struct task *t);
123
124 /** \cond */
125 extern void http_recv_init(struct receiver *r);
126 #define HTTP_RECEIVER {.name = "http", .init = http_recv_init},
127 extern void dccp_recv_init(struct receiver *r);
128 #define DCCP_RECEIVER {.name = "dccp", .init = dccp_recv_init},
129 extern void udp_recv_init(struct receiver *r);
130 #define UDP_RECEIVER {.name = "udp", .init = udp_recv_init},
131
132 extern struct receiver receivers[];
133 /** \endcond */
134