audiod_command.c: Trivial whitespace fix.
[paraslash.git] / audiod_command.c
1 /*
2 * Copyright (C) 2005 Andre Noll <maan@tuebingen.mpg.de>
3 *
4 * Licensed under the GPL v2. For licencing details see COPYING.
5 */
6
7 /** \file audiod_command.c Commands for para_audiod. */
8
9 #include <netinet/in.h>
10 #include <sys/socket.h>
11 #include <regex.h>
12 #include <sys/types.h>
13 #include <arpa/inet.h>
14 #include <sys/un.h>
15 #include <netdb.h>
16
17 #include "para.h"
18 #include "audiod.cmdline.h"
19 #include "audiod.command_list.h"
20 #include "list.h"
21 #include "sched.h"
22 #include "ggo.h"
23 #include "buffer_tree.h"
24 #include "filter.h"
25 #include "grab_client.h"
26 #include "error.h"
27 #include "audiod.h"
28 #include "net.h"
29 #include "daemon.h"
30 #include "string.h"
31 #include "write.h"
32 #include "fd.h"
33 #include "version.h"
34
35 extern struct sched sched;
36 extern char *stat_item_values[NUM_STAT_ITEMS];
37
38 typedef int audiod_command_handler_t(int, int, char **);
39 static audiod_command_handler_t AUDIOD_COMMAND_HANDLERS;
40
41 /* Defines one command of para_audiod. */
42 struct audiod_command {
43 const char *name;
44 /* Pointer to the function that handles the command. */
45 audiod_command_handler_t *handler;
46 /* One-line description. */
47 const char *description;
48 /* Summary of the command line options. */
49 const char *usage;
50 /* The long help text. */
51 const char *help;
52 };
53
54 static struct audiod_command audiod_cmds[] = {DEFINE_AUDIOD_CMD_ARRAY};
55
56 /** Iterate over the array of all audiod commands. */
57 #define FOR_EACH_COMMAND(c) for (c = 0; audiod_cmds[c].name; c++)
58
59 /** The maximal number of simultaneous connections. */
60 #define MAX_STAT_CLIENTS 50
61
62 /** Flags used for the stat command of para_audiod. */
63 enum stat_client_flags {
64 /** Enable parser-friendly output. */
65 SCF_PARSER_FRIENDLY = 1,
66 };
67
68 /**
69 * Describes a status client of para_audiod.
70 *
71 * There's one such structure per audiod client that sent the 'stat' command.
72 *
73 * A status client is identified by its file descriptor. para_audiod
74 * keeps a list of connected status clients.
75 */
76 struct stat_client {
77 /** The stat client's file descriptor. */
78 int fd;
79 /** Bitmask of those status items the client is interested in. */
80 uint64_t item_mask;
81 /** See \ref stat_client flags. */
82 unsigned flags;
83 /** Its entry in the list of stat clients. */
84 struct list_head node;
85 };
86
87 static INITIALIZED_LIST_HEAD(client_list);
88 static int num_clients;
89
90 /** The list of all status items used by para_{server,audiod,gui}. */
91 const char *status_item_list[] = {STATUS_ITEM_ARRAY};
92
93 static void dump_stat_client_list(void)
94 {
95 struct stat_client *sc;
96
97 list_for_each_entry(sc, &client_list, node)
98 PARA_INFO_LOG("stat client on fd %d\n", sc->fd);
99 }
100 /**
101 * Add a status client to the list.
102 *
103 * \param fd The file descriptor of the client.
104 * \param mask Bitfield of status items for this client.
105 * \param parser_friendly Enable parser-friendly output mode.
106 *
107 * Only those status items having the bit set in \a mask will be
108 * sent to the client.
109 *
110 * \return Positive value on success, or -E_TOO_MANY_CLIENTS if
111 * the number of connected clients exceeds #MAX_STAT_CLIENTS.
112 */
113 static int stat_client_add(int fd, uint64_t mask, int parser_friendly)
114 {
115 struct stat_client *new_client;
116 int ret;
117
118 if (num_clients >= MAX_STAT_CLIENTS) {
119 PARA_ERROR_LOG("maximal number of stat clients (%d) exceeded\n",
120 MAX_STAT_CLIENTS);
121 return -E_TOO_MANY_CLIENTS;
122 }
123 ret = dup(fd);
124 if (ret < 0)
125 return -ERRNO_TO_PARA_ERROR(errno);
126 new_client = para_calloc(sizeof(*new_client));
127 new_client->fd = ret;
128 PARA_INFO_LOG("adding client on fd %d\n", new_client->fd);
129 new_client->item_mask = mask;
130 if (parser_friendly)
131 new_client->flags = SCF_PARSER_FRIENDLY;
132 para_list_add(&new_client->node, &client_list);
133 dump_stat_client_list();
134 num_clients++;
135 return 1;
136 }
137
138 static void close_stat_client(struct stat_client *sc)
139 {
140 PARA_INFO_LOG("closing client fd %d\n", sc->fd);
141 close(sc->fd);
142 list_del(&sc->node);
143 free(sc);
144 num_clients--;
145 }
146
147 /**
148 * Empty the status clients list.
149 *
150 * This iterates over the list of connected status clients, closes each client
151 * file descriptor and frees the resources.
152 */
153 void close_stat_clients(void)
154 {
155 struct stat_client *sc, *tmp;
156
157 list_for_each_entry_safe(sc, tmp, &client_list, node)
158 close_stat_client(sc);
159 assert(num_clients == 0);
160 }
161
162 /**
163 * Write a message to all connected status clients.
164 *
165 * \param item_num The number of the status item of \a msg.
166 *
167 * On write errors, remove the status client from the client list and close its
168 * file descriptor.
169 */
170 void stat_client_write_item(int item_num)
171 {
172 struct stat_client *sc, *tmp;
173 struct para_buffer pb = {.flags = 0};
174 struct para_buffer pfpb = {.flags = PBF_SIZE_PREFIX};
175 const uint64_t one = 1;
176 char *msg = stat_item_values[item_num];
177 struct para_buffer *b;
178
179 list_for_each_entry_safe(sc, tmp, &client_list, node) {
180 int ret;
181
182 if (!((one << item_num) & sc->item_mask))
183 continue;
184 b = (sc->flags & SCF_PARSER_FRIENDLY)? &pfpb : &pb;
185 if (!b->buf)
186 (void)WRITE_STATUS_ITEM(b, item_num, "%s\n",
187 msg? msg : "");
188 ret = write(sc->fd, b->buf, b->offset);
189 if (ret == b->offset)
190 continue;
191 /* write error or short write */
192 close_stat_client(sc);
193 dump_stat_client_list();
194 }
195 free(pb.buf);
196 free(pfpb.buf);
197 }
198
199 /**
200 * Check if string is a known status item.
201 *
202 * \param item Buffer containing the text to check.
203 *
204 * \return If \a item is a valid status item, the number of that status item is
205 * returned. Otherwise, this function returns \p -E_UNKNOWN_STAT_ITEM.
206 */
207 static int stat_item_valid(const char *item)
208 {
209 int i;
210 if (!item || !*item) {
211 PARA_ERROR_LOG("%s\n", "no item");
212 return -E_UNKNOWN_STAT_ITEM;
213 }
214 FOR_EACH_STATUS_ITEM(i)
215 if (!strcmp(status_item_list[i], item))
216 return i;
217 PARA_ERROR_LOG("invalid stat item: %s\n", item);
218 return -E_UNKNOWN_STAT_ITEM;
219 }
220
221 static int client_write(int fd, const char *buf)
222 {
223 size_t len;
224
225 if (!buf)
226 return 0;
227 len = strlen(buf);
228 return write(fd, buf, len) != len? -E_CLIENT_WRITE: 1;
229 }
230
231 __malloc static char *audiod_status_string(void)
232 {
233 const char *status = (audiod_status == AUDIOD_ON)?
234 "on" : (audiod_status == AUDIOD_OFF)? "off": "sb";
235 return para_strdup(status);
236 }
237
238 static int dump_commands(int fd)
239 {
240 char *buf = para_strdup(""), *tmp = NULL;
241 int i;
242 ssize_t ret;
243
244 FOR_EACH_COMMAND(i) {
245 tmp = make_message("%s%s\t%s\n", buf, audiod_cmds[i].name,
246 audiod_cmds[i].description);
247 free(buf);
248 buf = tmp;
249 }
250 ret = client_write(fd, buf);
251 free(buf);
252 return ret;
253 }
254
255 static int com_help(int fd, int argc, char **argv)
256 {
257 int i, ret;
258 char *buf;
259 const char *dflt = "No such command. Available commands:\n";
260
261 if (argc < 2)
262 return dump_commands(fd);
263 FOR_EACH_COMMAND(i) {
264 if (strcmp(audiod_cmds[i].name, argv[1]))
265 continue;
266 buf = make_message(
267 "NAME\n\t%s -- %s\n"
268 "SYNOPSIS\n\tpara_audioc %s\n"
269 "DESCRIPTION\n%s\n",
270 argv[1],
271 audiod_cmds[i].description,
272 audiod_cmds[i].usage,
273 audiod_cmds[i].help
274 );
275 ret = client_write(fd, buf);
276 free(buf);
277 return ret;
278 }
279 ret = client_write(fd, dflt);
280 if (ret > 0)
281 ret = dump_commands(fd);
282 return ret;
283 }
284
285 static int com_tasks(int fd, __a_unused int argc, __a_unused char **argv)
286 {
287 char *tl = get_task_list(&sched);
288 int ret = 1;
289
290 if (tl)
291 ret = client_write(fd, tl);
292 free(tl);
293 return ret;
294 }
295
296 static int com_stat(int fd, int argc, char **argv)
297 {
298 int i, ret, parser_friendly = 0;
299 uint64_t mask = 0;
300 const uint64_t one = 1;
301 struct para_buffer b = {.flags = 0};
302
303 ret = mark_fd_nonblocking(fd);
304 if (ret < 0)
305 return ret;
306 for (i = 1; i < argc; i++) {
307 const char *arg = argv[i];
308 if (arg[0] != '-')
309 break;
310 if (!strcmp(arg, "--")) {
311 i++;
312 break;
313 }
314 if (!strncmp(arg, "-p", 2)) {
315 parser_friendly = 1;
316 b.flags = PBF_SIZE_PREFIX;
317 }
318 }
319 if (i >= argc)
320 mask--; /* set all bits */
321 for (; i < argc; i++) {
322 ret = stat_item_valid(argv[i]);
323 if (ret < 0)
324 return ret;
325 mask |= (one << ret);
326 }
327 PARA_INFO_LOG("mask: 0x%llx\n", (long long unsigned)mask);
328 FOR_EACH_STATUS_ITEM(i) {
329 char *item = stat_item_values[i];
330 if (!((one << i) & mask))
331 continue;
332 (void)WRITE_STATUS_ITEM(&b, i, "%s\n", item? item : "");
333 }
334 ret = client_write(fd, b.buf);
335 if (ret >= 0)
336 ret = stat_client_add(fd, mask, parser_friendly);
337 free(b.buf);
338 return ret;
339 }
340
341 static int com_grab(int fd, int argc, char **argv)
342 {
343 return grab_client_new(fd, argc, argv, &sched);
344 }
345
346 static int com_term(__a_unused int fd, __a_unused int argc, __a_unused char **argv)
347 {
348 return -E_AUDIOD_TERM;
349 }
350
351 static int com_on(__a_unused int fd, __a_unused int argc, __a_unused char **argv)
352 {
353 audiod_status = AUDIOD_ON;
354 return 1;
355 }
356
357 static int com_off(__a_unused int fd, __a_unused int argc, __a_unused char **argv)
358 {
359 audiod_status = AUDIOD_OFF;
360 return 1;
361 }
362
363 static int com_sb(__a_unused int fd, __a_unused int argc, __a_unused char **argv)
364 {
365 audiod_status = AUDIOD_STANDBY;
366 return 1;
367 }
368
369 static int com_cycle(__a_unused int fd, int argc, char **argv)
370 {
371 switch (audiod_status) {
372 case AUDIOD_ON:
373 return com_sb(fd, argc, argv);
374 break;
375 case AUDIOD_OFF:
376 return com_on(fd, argc, argv);
377 break;
378 case AUDIOD_STANDBY:
379 return com_off(fd, argc, argv);
380 break;
381 }
382 return 1;
383 }
384
385 static int com_version(int fd, int argc, char **argv)
386 {
387 int ret;
388 char *msg;
389
390 if (argc > 1 && strcmp(argv[1], "-v") == 0)
391 msg = make_message("%s", version_text("audiod"));
392 else
393 msg = make_message("%s\n", version_single_line("audiod"));
394 ret = client_write(fd, msg);
395 free(msg);
396 return ret;
397 }
398
399 static int check_perms(uid_t uid, uid_t *whitelist)
400 {
401 int i;
402
403 if (!conf.user_allow_given)
404 return 1;
405 for (i = 0; i < conf.user_allow_given; i++)
406 if (uid == whitelist[i])
407 return 1;
408 return -E_UCRED_PERM;
409 }
410
411 /**
412 * Handle arriving connections on the local socket.
413 *
414 * \param accept_fd The fd to accept connections on.
415 * \param rfds If \a accept_fd is not set in \a rfds, do nothing.
416 * \param uid_whitelist Array of UIDs which are allowed to connect.
417 *
418 * This is called in each iteration of the select loop. If there is an incoming
419 * connection on \a accept_fd, this function reads the command sent by the peer,
420 * checks the connecting user's permissions by using unix socket credentials
421 * (if supported by the OS) and calls the corresponding command handler if
422 * permissions are OK.
423 *
424 * \return Positive on success, negative on errors, zero if there was no
425 * connection to accept.
426 *
427 * \sa para_accept(), recv_cred_buffer()
428 * */
429 int handle_connect(int accept_fd, fd_set *rfds, uid_t *uid_whitelist)
430 {
431 int i, argc, ret, clifd;
432 char buf[MAXLINE], **argv = NULL;
433 struct sockaddr_un unix_addr;
434 uid_t uid;
435
436 ret = para_accept(accept_fd, rfds, &unix_addr, sizeof(struct sockaddr_un), &clifd);
437 if (ret <= 0)
438 return ret;
439 ret = recv_cred_buffer(clifd, buf, sizeof(buf) - 1);
440 if (ret < 0)
441 goto out;
442 uid = ret;
443 PARA_INFO_LOG("connection from user %i, buf: %s\n", ret, buf);
444 ret = check_perms(uid, uid_whitelist);
445 if (ret < 0)
446 goto out;
447 ret = create_argv(buf, "\n", &argv);
448 if (ret <= 0)
449 goto out;
450 argc = ret;
451 //PARA_INFO_LOG("argv[0]: %s, argc = %d\n", argv[0], argc);
452 FOR_EACH_COMMAND(i) {
453 if (strcmp(audiod_cmds[i].name, argv[0]))
454 continue;
455 ret = audiod_cmds[i].handler(clifd, argc, argv);
456 goto out;
457 }
458 ret = -E_INVALID_AUDIOD_CMD;
459 out:
460 free_argv(argv);
461 if (ret < 0 && ret != -E_CLIENT_WRITE) {
462 char *tmp = make_message("%s\n", para_strerror(-ret));
463 client_write(clifd, tmp);
464 free(tmp);
465 }
466 close(clifd);
467 return ret;
468 }
469
470 /**
471 * Send the current audiod status to all connected stat clients.
472 *
473 * \param force Whether to write unchanged items.
474 */
475 void audiod_status_dump(bool force)
476 {
477 char *old, *new;
478
479 old = stat_item_values[SI_PLAY_TIME];
480 new = get_time_string();
481 if (new) {
482 if (force || !old || strcmp(old, new)) {
483 free(old);
484 stat_item_values[SI_PLAY_TIME] = new;
485 stat_client_write_item(SI_PLAY_TIME);
486 } else
487 free(new);
488 }
489
490 new = daemon_get_uptime_str(now);
491 old = stat_item_values[SI_AUDIOD_UPTIME];
492 if (force || !old || strcmp(old, new)) {
493 free(old);
494 stat_item_values[SI_AUDIOD_UPTIME] = new;
495 stat_client_write_item(SI_AUDIOD_UPTIME);
496 } else
497 free(new);
498
499 old = stat_item_values[SI_AUDIOD_STATUS];
500 new = audiod_status_string();
501 if (force || !old || strcmp(old, new)) {
502 free(old);
503 stat_item_values[SI_AUDIOD_STATUS] = new;
504 stat_client_write_item(SI_AUDIOD_STATUS);
505 } else
506 free(new);
507
508 old = stat_item_values[SI_DECODER_FLAGS];
509 new = audiod_get_decoder_flags();
510 if (force || !old || strcmp(old, new)) {
511 free(old);
512 stat_item_values[SI_DECODER_FLAGS] = new;
513 stat_client_write_item(SI_DECODER_FLAGS);
514 } else
515 free(new);
516 }
517
518 /**
519 * Flush and send all status items.
520 *
521 * Send to each connected client the full status item list
522 * with empty values.
523 */
524 void clear_and_dump_items(void)
525 {
526 int i;
527
528 FOR_EACH_STATUS_ITEM(i) {
529 free(stat_item_values[i]);
530 stat_item_values[i] = NULL;
531 stat_client_write_item(i);
532 }
533 }