2 * Copyright (C) 2005-2009 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. */
24 #include "close_on_fork.h"
25 #include "chunk_queue.h"
28 /** Clients will be kicked if there are more than that many bytes pending. */
29 #define MAX_CQ_BYTES 40000
32 * Open a passive socket of given layer4 type.
34 * Set the resulting file descriptor to nonblocking mode and add it to the list
35 * of fds that are being closed in the child process when the server calls
38 * \param l4type The transport-layer protocol.
39 * \param port The port number.
41 * \return The listening fd on success, negative on errors.
43 static int open_sender(unsigned l4type, int port)
45 int fd, ret = para_listen(AF_UNSPEC, l4type, port);
50 ret = mark_fd_nonblocking(fd);
55 add_close_on_fork_list(fd);
60 * Shut down a client connected to a paraslash sender.
62 * \param sc The client to shut down.
63 * \param ss The sender whose clients are to be shut down.
65 * Close the file descriptor given by \a sc, remove it from the close-on-fork
66 * list, destroy the chunk queue of this client, delete the client from the
67 * list of connected clients and free the sender_client struct.
69 * \sa shutdown_clients().
71 void shutdown_client(struct sender_client *sc, struct sender_status *ss)
73 PARA_INFO_LOG("shutting down %s on fd %d\n", sc->name, sc->fd);
76 del_close_on_fork_list(sc->fd);
79 free(sc->private_data);
85 * Shut down all clients connected to a paraslash sender.
87 * \param ss The sender whose clients are to be shut down.
89 * This just loops over all connected clients and calls shutdown_client()
92 void shutdown_clients(struct sender_status *ss)
94 struct sender_client *sc, *tmp;
95 list_for_each_entry_safe(sc, tmp, &ss->client_list, node)
96 shutdown_client(sc, ss);
99 static int queue_chunk_or_shutdown(struct sender_client *sc,
100 struct sender_status *ss, const char *buf, size_t num_bytes)
102 int ret = cq_enqueue(sc->cq, buf, num_bytes);
104 shutdown_client(sc, ss);
109 * Try to empty the chunk queue for this fd.
111 * \param fd The file descriptor.
112 * \param cq The list of queued chunks.
113 * \param max_bytes_per_write Do not send more than this in one go.
115 * \return Negative on errors, zero if not everything was sent, one otherwise.
117 int send_queued_chunks(int fd, struct chunk_queue *cq,
118 size_t max_bytes_per_write)
120 struct queued_chunk *qc;
121 while ((qc = cq_peek(cq))) {
125 cq_get(qc, &buf, &len);
126 ret = write_nonblock(fd, buf, len, max_bytes_per_write);
138 * Send one chunk of audio data to a connected client.
140 * \param sc The client.
141 * \param ss The sender.
142 * \param max_bytes_per_write Split writes to chunks of at most that many bytes.
143 * \param current_chunk The number of the chunk to write.
144 * \param buf The data to write.
145 * \param len The number of bytes of \a buf.
146 * \param header_buf The audio file header.
147 * \param header_len The number of bytes of \a header_buf.
149 * On errors, the client is shut down. If only a part of the buffer could be
150 * written, the remainder is put into the chunk queue for that client.
152 void send_chunk(struct sender_client *sc, struct sender_status *ss,
153 size_t max_bytes_per_write, long unsigned current_chunk,
154 const char *buf, size_t len, const char *header_buf,
159 if (!sc->header_sent && current_chunk) {
160 if (header_buf && header_len > 0) {
161 ret = queue_chunk_or_shutdown(sc, ss, header_buf, header_len);
167 ret = send_queued_chunks(sc->fd, sc->cq, max_bytes_per_write);
169 shutdown_client(sc, ss);
174 if (!ret) { /* still data left in the queue */
175 ret = queue_chunk_or_shutdown(sc, ss, buf, len);
178 ret = write_nonblock(sc->fd, buf, len, max_bytes_per_write);
180 shutdown_client(sc, ss);
184 ret = queue_chunk_or_shutdown(sc, ss, buf + ret, len - ret);
187 PARA_NOTICE_LOG("%s\n", para_strerror(-ret));
191 * Initialize a struct sender status.
193 * \param ss The struct to initialize.
194 * \param access_arg The array of access arguments given at the command line.
195 * \param num_access_args The number of elements in \a access_arg.
196 * \param port The tcp or dccp port to listen on.
197 * \param max_clients The maximal number of simultaneous connections.
198 * \param default_deny Whether a blacklist should be used for access control.
200 void init_sender_status(struct sender_status *ss, char **access_arg,
201 int num_access_args, int port, int max_clients, int default_deny)
204 INIT_LIST_HEAD(&ss->client_list);
206 acl_init(&ss->acl, access_arg, num_access_args);
208 ss->max_clients = max_clients;
209 ss->default_deny = default_deny;
213 * Return a string containing the current status of a sender.
215 * \param ss The sender.
216 * \param name Used for printing the header line.
218 * \return The string printed in the "si" command.
220 char *get_sender_info(struct sender_status *ss, const char *name)
222 char *clnts = NULL, *ret;
223 struct sender_client *sc, *tmp_sc;
225 char *acl_contents = acl_get_contents(&ss->acl);
226 list_for_each_entry_safe(sc, tmp_sc, &ss->client_list, node) {
227 char *tmp = make_message("%s%s ", clnts? clnts : "", sc->name);
235 "\tnumber of connected clients: %d\n"
236 "\tmaximal number of clients: %d%s\n"
237 "\tconnected clients: %s\n"
238 "\taccess %s list: %s\n",
240 (ss->listen_fd >= 0)? "on" : "off",
244 ss->max_clients > 0? "" : " (unlimited)",
245 clnts? clnts : "(none)",
246 ss->default_deny? "allow" : "deny",
247 acl_contents? acl_contents : "(empty)"
255 * Allow connections from the given range of IP addresses.
257 * \param scd Contains the IP and the netmask.
258 * \param ss The sender.
260 * \sa generic_com_deny().
262 void generic_com_allow(struct sender_command_data *scd,
263 struct sender_status *ss)
265 acl_allow(scd->host, scd->netmask, &ss->acl, ss->default_deny);
269 * Deny connections from the given range of IP addresses.
271 * \param scd see \ref generic_com_allow().
272 * \param ss see \ref generic_com_allow().
274 * \sa generic_com_allow().
276 void generic_com_deny(struct sender_command_data *scd,
277 struct sender_status *ss)
279 acl_deny(scd->host, scd->netmask, &ss->acl, ss->default_deny);
283 * Activate a paraslash sender.
285 * \param ss The sender to activate.
286 * \param protocol The symbolic name of the transport-layer protocol.
290 int generic_com_on(struct sender_status *ss, unsigned protocol)
294 if (ss->listen_fd >= 0)
296 ret = open_sender(protocol, ss->port);
304 * Deactivate a paraslash sender.
306 * Shutdown all connected clients and stop listening on the TCP/DCCP socket.
308 * \param ss The sender to deactivate.
310 * \sa \ref del_close_on_fork_list(), shutdown_clients().
312 void generic_com_off(struct sender_status *ss)
314 if (ss->listen_fd < 0)
316 PARA_NOTICE_LOG("closing port %d\n", ss->port);
317 close(ss->listen_fd);
318 del_close_on_fork_list(ss->listen_fd);
319 shutdown_clients(ss);
324 * Accept a connection on the socket this server is listening on.
326 * \param ss The sender whose listening fd is ready for reading.
328 * This must be called only if the socket fd of \a ss is ready for reading. It
329 * calls para_accept() to accept the connection and performs the following
330 * actions on the resulting file descriptor \a fd:
332 * - Checks whether the maximal number of connections are exceeded.
333 * - Sets \a fd to nonblocking mode.
334 * - Checks the acl of the sender to find out whether connections
335 * are allowed from the IP of the connecting peer.
336 * - Increases the number of connections for this sender.
337 * - Creates and initializes a new chunk queue for queuing network
338 * packets that can not be sent immediately.
339 * - Allocates a new struct sender_client and fills in its \a fd, \a cq
340 * and \a name members.
341 * - Adds \a fd to the list of connected clients for this sender.
342 * - Adds \a fd to the list of file descriptors that should be closed
343 * in the child process when the server calls fork().
345 * \return A pointer to the allocated sender_client structure on success, \p
348 * \sa \ref para_accept(), \ref mark_fd_nonblocking(), \ref acl_check_access(),
349 * \ref cq_new(), \ref add_close_on_fork_list().
351 struct sender_client *accept_sender_client(struct sender_status *ss)
353 struct sender_client *sc;
354 int fd, ret = para_accept(ss->listen_fd, NULL, 0);
356 PARA_ERROR_LOG("%s\n", para_strerror(-ret));
360 ret = -E_MAX_CLIENTS;
361 if (ss->max_clients > 0 && ss->num_clients >= ss->max_clients)
363 ret = mark_fd_nonblocking(fd);
366 ret = acl_check_access(fd, &ss->acl, ss->default_deny);
370 sc = para_calloc(sizeof(*sc));
372 sc->name = make_message("%s", remote_name(fd));
373 sc->cq = cq_new(MAX_CQ_BYTES);
374 para_list_add(&sc->node, &ss->client_list);
375 add_close_on_fork_list(fd);
376 PARA_INFO_LOG("accepted client #%d: %s (fd %d)\n", ss->num_clients,
380 PARA_WARNING_LOG("%s\n", para_strerror(-ret));
386 * Get the generic help text.
388 * \return A dynamically allocated string containing the help text for
389 * a paraslash sender.
391 char *generic_sender_help(void)
395 "usage: {allow|deny} IP[/netmask]\n"
396 " where mask defaults to 32\n"
397 "example: allow 192.168.0.1/24\n"
401 static int parse_fec_parms(const char *arg, struct sender_command_data *scd)
404 char *a = para_strdup(arg), *b = a, *e = strchr(b, ':');
405 int ret = -E_COMMAND_SYNTAX;
407 /* parse max slice bytes */
411 ret = para_atoi32(b, &val);
414 ret = -ERRNO_TO_PARA_ERROR(EINVAL);
415 if (val < 0 || val > 65535)
417 scd->max_slice_bytes = val;
418 /* parse data_slices_per_group */
421 ret = -E_COMMAND_SYNTAX;
425 ret = para_atoi32(b, &val);
428 ret = -ERRNO_TO_PARA_ERROR(EINVAL);
429 if (val < 0 || val > 255)
431 scd->data_slices_per_group = val;
432 /* parse slices_per_group */
434 ret = para_atoi32(b, &val);
437 ret = -ERRNO_TO_PARA_ERROR(EINVAL);
438 if (val < 0 || val < scd->data_slices_per_group)
440 scd->slices_per_group = val;
448 * Parse a FEC URL string.
450 * \param arg the URL string to parse.
451 * \param scd The structure containing host, port and the FEC parameters.
455 * A FEC URL consists of an ordinary URL string according to RFC 3986,
456 * optionally followed by a slash and the three FEC parameters slice_size,
457 * data_slices_per_group and slices_per_group. The three FEC parameters are
458 * separated by colons.
460 * \sa \ref parse_url().
462 int parse_fec_url(const char *arg, struct sender_command_data *scd)
465 ssize_t len = sizeof(scd->host);
466 char *a = para_strdup(arg), *p = strchr(a, '/');
472 ret = -ERRNO_TO_PARA_ERROR(EINVAL);
473 if (!parse_url(a, scd->host, len, &scd->port))
476 ret = parse_fec_parms(p + 1, scd);
479 /* use default fec parameters. */
480 scd->max_slice_bytes = 1490;
481 scd->slices_per_group = 16;
482 scd->data_slices_per_group = 14;