3d87008850a8ab3c39b3f1711d5aca1b2e2f3a45
2 * Copyright (C) 2005-2008 Andre Noll <maan@systemlinux.org>
4 * Licensed under the GPL v2. For licencing details see COPYING.
7 /** \file send_common.c Functions used by more than one paraslash sender. */
21 #include "close_on_fork.h"
22 #include "chunk_queue.h"
25 /** Clients will be kicked if there are more than that many bytes pending. */
26 #define MAX_CQ_BYTES 40000
29 * Open a passive socket of given layer4 type.
31 * Set the resulting file descriptor to nonblocking mode and add it to the list
32 * of fds that are being closed in the child process when the server calls
35 * \param l4type The transport-layer protocol.
36 * \param port The port number.
38 * \return The listening fd on success, negative on errors.
40 static int open_sender(unsigned l4type
, int port
)
42 int fd
, ret
= para_listen(AF_UNSPEC
, l4type
, port
);
47 ret
= mark_fd_nonblocking(fd
);
52 add_close_on_fork_list(fd
);
57 * Shut down a client connected to a paraslash sender.
59 * \param sc The client to shut down.
60 * \param ss The sender whose clients are to be shut down.
62 * Close the file descriptor given by \a sc, remove it from the close-on-fork
63 * list, destroy the chunk queue of this client, delete the client from the
64 * list of connected clients and free the sender_client struct.
66 * \sa shutdown_clients().
68 void shutdown_client(struct sender_client
*sc
, struct sender_status
*ss
)
70 PARA_INFO_LOG("shutting down %s on fd %d\n", sc
->name
, sc
->fd
);
73 del_close_on_fork_list(sc
->fd
);
76 free(sc
->private_data
);
82 * Shut down all clients connected to a paraslash sender.
84 * \param ss The sender whose clients are to be shut down.
86 * This just loops over all connected clients and calls shutdown_client()
89 void shutdown_clients(struct sender_status
*ss
)
91 struct sender_client
*sc
, *tmp
;
92 list_for_each_entry_safe(sc
, tmp
, &ss
->client_list
, node
)
93 shutdown_client(sc
, ss
);
97 * Write a buffer to a non-blocking file descriptor.
99 * \param fd The file descriptor.
100 * \param buf the buffer to write.
101 * \param len the number of bytes of \a buf.
102 * \param max_bytes_per_write Do not write more than that many bytes at once.
104 * If \a max_bytes_per_write is non-zero, do not send more than that many bytes
107 * EAGAIN is not considered an error condition. For example CCID3 has a
108 * sending wait queue which fills up and is emptied asynchronously. The EAGAIN
109 * case means that there is currently no space in the wait queue, but this can
110 * change at any moment.
112 * \return Negative on errors, number of bytes written else.
114 static int write_nonblock(int fd
, const char *buf
, size_t len
,
115 size_t max_bytes_per_write
)
120 while (written
< len
) {
121 size_t num
= len
- written
;
123 if (max_bytes_per_write
&& max_bytes_per_write
< num
)
124 num
= max_bytes_per_write
;
125 ret
= write(fd
, buf
+ written
, num
);
126 if (ret
< 0 && errno
== EAGAIN
)
129 return -ERRNO_TO_PARA_ERROR(errno
);
135 static int queue_chunk_or_shutdown(struct sender_client
*sc
,
136 struct sender_status
*ss
, const char *buf
, size_t num_bytes
)
138 int ret
= cq_enqueue(sc
->cq
, buf
, num_bytes
);
140 shutdown_client(sc
, ss
);
144 /* return: negative on errors, zero if not everything was sent, one otherwise */
145 static int send_queued_chunks(struct sender_client
*sc
,
146 size_t max_bytes_per_write
)
148 struct queued_chunk
*qc
;
149 while ((qc
= cq_peek(sc
->cq
))) {
153 cq_get(qc
, &buf
, &len
);
154 ret
= write_nonblock(sc
->fd
, buf
, len
, max_bytes_per_write
);
157 cq_update(sc
->cq
, ret
);
166 * Send one chunk of audio data to a connected client.
168 * \param sc The client.
169 * \param ss The sender.
170 * \param max_bytes_per_write Split writes to chunks of at most that many bytes.
171 * \param current_chunk The number of the chunk to write.
172 * \param buf The data to write.
173 * \param len The number of bytes of \a buf.
174 * \param header_buf The audio file header.
175 * \param header_len The number of bytes of \a header_buf.
177 * On errors, the client is shut down. If only a part of the buffer could be
178 * written, the remainder is put into the chunk queue for that client.
180 void send_chunk(struct sender_client
*sc
, struct sender_status
*ss
,
181 size_t max_bytes_per_write
, long unsigned current_chunk
,
182 const char *buf
, size_t len
, const char *header_buf
,
187 if (!sc
->header_sent
&& current_chunk
) {
188 if (header_buf
&& header_len
> 0) {
189 ret
= queue_chunk_or_shutdown(sc
, ss
, header_buf
, header_len
);
195 ret
= send_queued_chunks(sc
, max_bytes_per_write
);
197 shutdown_client(sc
, ss
);
202 if (!ret
) { /* still data left in the queue */
203 ret
= queue_chunk_or_shutdown(sc
, ss
, buf
, len
);
206 ret
= write_nonblock(sc
->fd
, buf
, len
, max_bytes_per_write
);
208 shutdown_client(sc
, ss
);
212 ret
= queue_chunk_or_shutdown(sc
, ss
, buf
+ ret
, len
- ret
);
215 PARA_NOTICE_LOG("%s\n", para_strerror(-ret
));
219 * Initialize a struct sender status.
221 * \param ss The struct to initialize.
222 * \param access_arg The array of access arguments given at the command line.
223 * \param num_access_args The number of elements in \a access_arg.
224 * \param port The tcp or dccp port to listen on.
225 * \param max_clients The maximal number of simultaneous connections.
226 * \param default_deny Whether a blacklist should be used for access control.
228 void init_sender_status(struct sender_status
*ss
, char **access_arg
,
229 int num_access_args
, int port
, int max_clients
, int default_deny
)
232 INIT_LIST_HEAD(&ss
->client_list
);
234 acl_init(&ss
->acl
, access_arg
, num_access_args
);
236 ss
->max_clients
= max_clients
;
237 ss
->default_deny
= default_deny
;
241 * Return a string containing the current status of a sender.
243 * \param ss The sender.
244 * \param name Used for printing the header line.
246 * \return The string printed in the "si" command.
248 char *get_sender_info(struct sender_status
*ss
, char *name
)
250 char *clnts
= NULL
, *ret
;
251 struct sender_client
*sc
, *tmp_sc
;
253 char *acl_contents
= acl_get_contents(&ss
->acl
);
254 list_for_each_entry_safe(sc
, tmp_sc
, &ss
->client_list
, node
) {
255 char *tmp
= make_message("%s%s ", clnts
? clnts
: "", sc
->name
);
263 "\tnumber of connected clients: %d\n"
264 "\tmaximal number of clients: %d%s\n"
265 "\tconnected clients: %s\n"
266 "\taccess %s list: %s\n",
268 (ss
->listen_fd
>= 0)? "on" : "off",
272 ss
->max_clients
> 0? "" : " (unlimited)",
273 clnts
? clnts
: "(none)",
274 ss
->default_deny
? "allow" : "deny",
275 acl_contents
? acl_contents
: "(empty)"
283 * Allow connections from the given range of IP addresses.
285 * \param scd Contains the IP and the netmask.
286 * \param ss The sender.
288 * \sa generic_com_deny().
290 void generic_com_allow(struct sender_command_data
*scd
,
291 struct sender_status
*ss
)
293 acl_allow(scd
->addr
, scd
->netmask
, &ss
->acl
, ss
->default_deny
);
297 * Deny connections from the given range of IP addresses.
299 * \param scd see \ref generic_com_allow().
300 * \param ss see \ref generic_com_allow().
302 * \sa generic_com_allow().
304 void generic_com_deny(struct sender_command_data
*scd
,
305 struct sender_status
*ss
)
307 acl_deny(scd
->addr
, scd
->netmask
, &ss
->acl
, ss
->default_deny
);
311 * Activate a paraslash sender.
313 * \param ss The sender to activate.
314 * \param protocol The symbolic name of the transport-layer protocol.
318 int generic_com_on(struct sender_status
*ss
, unsigned protocol
)
322 if (ss
->listen_fd
>= 0)
324 ret
= open_sender(protocol
, ss
->port
);
332 * Deactivate a paraslash sender.
334 * Shutdown all connected clients and stop listening on the TCP/DCCP socket.
336 * \param ss The sender to deactivate.
338 * \sa \ref del_close_on_fork_list(), shutdown_clients().
340 void generic_com_off(struct sender_status
*ss
)
342 if (ss
->listen_fd
< 0)
344 PARA_NOTICE_LOG("closing port %d\n", ss
->port
);
345 close(ss
->listen_fd
);
346 del_close_on_fork_list(ss
->listen_fd
);
347 shutdown_clients(ss
);
352 * Accept a connection on the socket this server is listening on.
354 * \param ss The sender whose listening fd is ready for reading.
356 * This must be called only if the socket fd of \a ss is ready for reading. It
357 * calls para_accept() to accept the connection and performs the following
358 * actions on the resulting file descriptor \a fd:
360 * - Checks whether the maximal number of connections are exceeded.
361 * - Sets \a fd to nonblocking mode.
362 * - Checks the acl of the sender to find out whether connections
363 * are allowed from the IP of the connecting peer.
364 * - Increases the number of connections for this sender.
365 * - Creates and initializes a new chunk queue for queuing network
366 * packets that can not be sent immediately.
367 * - Allocates a new struct sender_client and fills in its \a fd, \a cq
368 * and \a name members.
369 * - Adds \a fd to the list of connected clients for this sender.
370 * - Adds \a fd to the list of file descriptors that should be closed
371 * in the child process when the server calls fork().
373 * \return A pointer to the allocated sender_client structure on success, \p
376 * \sa \ref para_accept(), \ref mark_fd_nonblocking(), \ref acl_check_access(),
377 * \ref cq_new(), \ref add_close_on_fork_list().
379 struct sender_client
*accept_sender_client(struct sender_status
*ss
)
381 struct sender_client
*sc
;
382 int fd
, ret
= para_accept(ss
->listen_fd
, NULL
, 0);
384 PARA_ERROR_LOG("%s\n", para_strerror(-ret
));
388 ret
= -E_MAX_CLIENTS
;
389 if (ss
->max_clients
> 0 && ss
->num_clients
>= ss
->max_clients
)
391 ret
= mark_fd_nonblocking(fd
);
394 ret
= acl_check_access(fd
, &ss
->acl
, ss
->default_deny
);
398 sc
= para_calloc(sizeof(*sc
));
400 sc
->name
= make_message("%s", remote_name(fd
));
401 sc
->cq
= cq_new(MAX_CQ_BYTES
);
402 para_list_add(&sc
->node
, &ss
->client_list
);
403 add_close_on_fork_list(fd
);
404 PARA_INFO_LOG("accepted client #%d: %s (fd %d)\n", ss
->num_clients
,
408 PARA_WARNING_LOG("%s\n", para_strerror(-ret
));
414 * Get the generic help text.
416 * \return A dynamically allocated string containing the help text for
417 * a paraslash sender.
419 char *generic_sender_help(void)
423 "usage: {allow|deny} IP mask\n"
424 "example: allow 127.0.0.1 32\n"