72c7a6c6c6313e15d8cd64ceb0997624ef0be52e
[paraslash.git] / send.h
1 /*
2 * Copyright (C) 2005-2010 Andre Noll <maan@systemlinux.org>
3 *
4 * Licensed under the GPL v2. For licencing details see COPYING.
5 */
6
7 /** \file send.h Sender-related defines and structures. */
8
9 /** The sender subcommands. */
10 enum {SENDER_ADD, SENDER_DELETE, SENDER_ALLOW, SENDER_DENY, SENDER_ON, SENDER_OFF, NUM_SENDER_CMDS};
11
12 /**
13 * Each paraslash sender may register arbitrary many clients to the virtual
14 * streaming system, possibly with varying fec parameters. In order to do so,
15 * it must allocate a \a fec_client_parms structure and pass it to \ref
16 * add_fec_client.
17 *
18 * Clients are automatically removed from that list by the vss if an error
19 * occurs, or if the sender requests deletion of a client by calling \ref
20 * vss_del_fec_client().
21 */
22 struct fec_client;
23
24 /** FEC parameters requested by FEC clients. */
25 struct fec_client_parms {
26 /** Number of data slices plus redundant slices. */
27 uint8_t slices_per_group;
28 /** Number of slices minus number of redundant slices. */
29 uint8_t data_slices_per_group;
30 /** Maximal number of bytes per slice, initially zero. */
31 uint16_t max_slice_bytes;
32 };
33
34 /**
35 * Describes one supported sender of para_server.
36 *
37 * \sa http_send.c udp_send.c, dccp_send.c.
38 */
39 struct sender {
40 /** The name of the sender. */
41 const char *name;
42 /**
43 * The init function of this sender.
44 *
45 * It must fill in all function pointers of \a s as well as the \a
46 * client_cmds array, see below. It should also do all necessary
47 * preparations to init this sending facility, for example it could
48 * open a tcp port.
49 */
50 void (*init)(struct sender *s);
51 /**
52 * Return the help text of this sender.
53 *
54 * The result must be dynamically allocated and is freed by the caller.
55 */
56 char* (*help)(void);
57 /**
58 * Return current status info about this sender.
59 *
60 * The result must be dynamically allocated and is freed by the caller.
61 */
62 char* (*info)(void);
63 /**
64 * The send-hook.
65 *
66 * It gets called whenever para_server is playing and the current
67 * audio format handler indicates that another chunk of data should
68 * be sent now. The two parameters \a current_chunk and \a chunks_sent
69 * only differ if the stream was repositioned by the \a ff or \a jmp
70 * command. Of course, \a buf is a pointer to the chunk of data which
71 * should be sent, and \a len is the length of this buffer.
72 */
73 void (*send)(long unsigned current_chunk, long unsigned chunks_sent,
74 const char *buf, size_t len, const char *header_buf,
75 size_t header_len);
76
77 /**
78 * Obtain the FEC parameters of a FEC client.
79 *
80 * This is called once by vss.c at the beginning of a stream. Senders
81 * are supposed to set \a fcp to a struct which is suitable for the FEC
82 * client identified by \a private_data.
83 */
84 int (*open)(void *client, struct fec_client_parms **fcp);
85 /**
86 * Send the next slice to a FEC client.
87 *
88 * Called by vss.c when the next slice should be sent to the FEC client
89 * identified by \a private_data, the pointer which was previously
90 * passed to vss_add_fec_target().
91 */
92 int (*send_fec)(char *buf, size_t num_bytes, void *private_data);
93 /**
94 * Add file descriptors to fd_sets.
95 *
96 * The pre_select function of each supported sender is called just before
97 * para_server enters its main select loop. Each sender may add its own
98 * file descriptors to the \a rfds or the \a wfds set.
99 *
100 * If a file descriptor was added, \a max_fileno must be increased by
101 * this function, if necessary.
102 *
103 * \sa select(2).
104 */
105 void (*pre_select)(int *max_fileno, fd_set *rfds, fd_set *wfds);
106 /**
107 * Handle the file descriptors which are ready for I/O.
108 *
109 * If the pre_select hook added one ore more file descriptors to the
110 * read or write set, this is the hook to check the result and do any
111 * I/O on those descriptors which are ready for reading/writing.
112 */
113 void (*post_select)(fd_set *rfds, fd_set *wfds);
114 /**
115 * Terminate all connected clients.
116 *
117 * This is called e.g. if the stop command was executed. It should make
118 * the clients aware of the end-of-file condition.
119 */
120 void (*shutdown_clients)(void);
121 /**
122 * Array of function pointers for the sender subcommands.
123 *
124 * Each sender may implement any subset of the sender commands by
125 * filling in the appropriate function pointer in the array. A \p NULL
126 * pointer means this command is not implemented by this sender.
127 */
128 int (*client_cmds[NUM_SENDER_CMDS])(struct sender_command_data*);
129 };
130
131 /** Describes one client, connected to a paraslash sender. */
132 struct sender_client {
133 /** The file descriptor of the client. */
134 int fd;
135 /** The socket "name" of the client. */
136 char *name;
137 /** The position of this client in the client list. */
138 struct list_head node;
139 /** Non-zero if audio file header has been sent. */
140 int header_sent;
141 /** The list of pending chunks for this client. */
142 struct chunk_queue *cq;
143 /** Data specific to the particular sender. */
144 void *private_data;
145 };
146
147 /** Describes the current status of one paraslash sender. */
148 struct sender_status {
149 /** The file descriptor of the socket this sender is listening on. */
150 int listen_fd;
151 /** The TCP/DCCP port used by this sender. */
152 int port;
153 /** The current number of simultaneous connections. */
154 int num_clients;
155 /** The maximal number of simultaneous connections. */
156 int max_clients;
157 /** Whether the access control list is a whitelist. */
158 int default_deny;
159 /** The whitelist/blacklist. */
160 struct list_head acl;
161 /** The list of connected clients. */
162 struct list_head client_list;
163 };
164
165 void shutdown_client(struct sender_client *sc, struct sender_status *ss);
166 void shutdown_clients(struct sender_status *ss);
167 void send_chunk(struct sender_client *sc, struct sender_status *ss,
168 size_t max_bytes_per_write, long unsigned current_chunk,
169 const char *buf, size_t len, const char *header_buf,
170 size_t header_len);
171 void init_sender_status(struct sender_status *ss, char **access_arg, int num_access_args,
172 int port, int max_clients, int default_deny);
173 char *get_sender_info(struct sender_status *ss, const char *name);
174
175 void generic_com_allow(struct sender_command_data *scd,
176 struct sender_status *ss);
177 void generic_com_deny(struct sender_command_data *scd,
178 struct sender_status *ss);
179 int generic_com_on(struct sender_status *ss, unsigned protocol);
180 void generic_com_off(struct sender_status *ss);
181 char *generic_sender_help(void);
182 struct sender_client *accept_sender_client(struct sender_status *ss, fd_set *rfds);
183 int send_queued_chunks(int fd, struct chunk_queue *cq,
184 size_t max_bytes_per_write);
185 int parse_fec_url(const char *arg, struct sender_command_data *scd);