audiod_command.c

   1 /*
   2  * Copyright (C) 2005-2013 Andre Noll <maan@systemlinux.org>
   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 "list.h"
  20 #include "sched.h"
  21 #include "ggo.h"
  22 #include "buffer_tree.h"
  23 #include "filter.h"
  24 #include "grab_client.h"
  25 #include "error.h"
  26 #include "audiod.h"
  27 #include "net.h"
  28 #include "daemon.h"
  29 #include "string.h"
  30 #include "write.h"
  31 #include "fd.h"
  32 #include "audiod_command_list.h"
  33
  34 extern struct sched sched;
  35 extern char *stat_item_values[NUM_STAT_ITEMS];
  36
  37
  38 static struct audiod_command audiod_cmds[] = {DEFINE_AUDIOD_CMD_ARRAY};
  39
  40 /** Iterate over the array of all audiod commands. */
  41 #define FOR_EACH_COMMAND(c) for (c = 0; audiod_cmds[c].name; c++)
  42
  43 /** The maximal number of simultaneous connections. */
  44 #define MAX_STAT_CLIENTS 50
  45
  46 /** Flags used for the stat command of para_audiod. */
  47 enum stat_client_flags {
  48         /** Enable parser-friendly output. */
  49         SCF_PARSER_FRIENDLY = 1,
  50 };
  51
  52 /**
  53  * Describes a status client of para_audiod.
  54  *
  55  * There's one such structure per audiod client that sent the 'stat' command.
  56  *
  57  * A status client is identified by its file descriptor.  para_audiod
  58  * keeps a list of connected status clients.
  59  */
  60 struct stat_client {
  61         /** The stat client's file descriptor. */
  62         int fd;
  63         /** Bitmask of those status items the client is interested in. */
  64         uint64_t item_mask;
  65         /** See \ref stat_client flags. s*/
  66         unsigned flags;
  67         /** Its entry in the list of stat clients. */
  68         struct list_head node;
  69 };
  70
  71 static INITIALIZED_LIST_HEAD(client_list);
  72 static int num_clients;
  73
  74 /** The list of all status items used by para_{server,audiod,gui}. */
  75 const char *status_item_list[] = {STATUS_ITEM_ARRAY};
  76
  77 static void dump_stat_client_list(void)
  78 {
  79         struct stat_client *sc;
  80
  81         list_for_each_entry(sc, &client_list, node)
  82                 PARA_INFO_LOG("stat client on fd %d\n", sc->fd);
  83 }
  84 /**
  85  * Add a status client to the list.
  86  *
  87  * \param fd The file descriptor of the client.
  88  * \param mask Bitfield of status items for this client.
  89  * \param parser_friendly Enable parser-friendly output mode.
  90  *
  91  * Only those status items having the bit set in \a mask will be
  92  * sent to the client.
  93  *
  94  * \return Positive value on success, or -E_TOO_MANY_CLIENTS if
  95  * the number of connected clients exceeds #MAX_STAT_CLIENTS.
  96  */
  97 static int stat_client_add(int fd, uint64_t mask, int parser_friendly)
  98 {
  99         struct stat_client *new_client;
 100
 101         if (num_clients >= MAX_STAT_CLIENTS) {
 102                 PARA_ERROR_LOG("maximal number of stat clients (%d) exceeded\n",
 103                         MAX_STAT_CLIENTS);
 104                 return -E_TOO_MANY_CLIENTS;
 105         }
 106         PARA_INFO_LOG("adding client on fd %d\n", fd);
 107         new_client = para_calloc(sizeof(struct stat_client));
 108         new_client->fd = fd;
 109         new_client->item_mask = mask;
 110         if (parser_friendly)
 111                 new_client->flags = SCF_PARSER_FRIENDLY;
 112         para_list_add(&new_client->node, &client_list);
 113         dump_stat_client_list();
 114         num_clients++;
 115         return 1;
 116 }
 117
 118 static void close_stat_client(struct stat_client *sc)
 119 {
 120         PARA_INFO_LOG("closing client fd %d\n", sc->fd);
 121         close(sc->fd);
 122         list_del(&sc->node);
 123         free(sc);
 124         num_clients--;
 125 }
 126
 127 /**
 128  * Empty the status clients list.
 129  *
 130  * This iterates over the list of connected status clients, closes each client
 131  * file descriptor and frees the resources.
 132  */
 133 void close_stat_clients(void)
 134 {
 135         struct stat_client *sc, *tmp;
 136
 137         list_for_each_entry_safe(sc, tmp, &client_list, node)
 138                 close_stat_client(sc);
 139         assert(num_clients == 0);
 140 }
 141
 142 /**
 143  * Write a message to all connected status clients.
 144  *
 145  * \param item_num The number of the status item of \a msg.
 146  *
 147  * On write errors, remove the status client from the client list and close its
 148  * file descriptor.
 149  */
 150 void stat_client_write_item(int item_num)
 151 {
 152         struct stat_client *sc, *tmp;
 153         struct para_buffer pb = {.flags = 0};
 154         struct para_buffer pfpb = {.flags = PBF_SIZE_PREFIX};
 155         const uint64_t one = 1;
 156         char *msg = stat_item_values[item_num];
 157         struct para_buffer *b;
 158
 159         list_for_each_entry_safe(sc, tmp, &client_list, node) {
 160                 int ret;
 161
 162                 if (!((one << item_num) & sc->item_mask))
 163                         continue;
 164                 b = (sc->flags & SCF_PARSER_FRIENDLY)? &pfpb : &pb;
 165                 if (!b->buf)
 166                         (void)WRITE_STATUS_ITEM(b, item_num, "%s\n",
 167                                 msg? msg : "");
 168                 ret = write(sc->fd, b->buf, b->offset);
 169                 if (ret == b->offset)
 170                         continue;
 171                 /* write error or short write */
 172                 close_stat_client(sc);
 173                 dump_stat_client_list();
 174         }
 175         free(pb.buf);
 176         free(pfpb.buf);
 177 }
 178
 179 /**
 180  * Check if string is a known status item.
 181  *
 182  * \param item Buffer containing the text to check.
 183  *
 184  * \return If \a item is a valid status item, the number of that status item is
 185  * returned. Otherwise, this function returns \p -E_UNKNOWN_STAT_ITEM.
 186  */
 187 static int stat_item_valid(const char *item)
 188 {
 189         int i;
 190         if (!item || !*item) {
 191                 PARA_ERROR_LOG("%s\n", "no item");
 192                 return -E_UNKNOWN_STAT_ITEM;
 193         }
 194         FOR_EACH_STATUS_ITEM(i)
 195                 if (!strcmp(status_item_list[i], item))
 196                         return i;
 197         PARA_ERROR_LOG("invalid stat item: %s\n", item);
 198         return -E_UNKNOWN_STAT_ITEM;
 199 }
 200
 201 static int client_write(int fd, const char *buf)
 202 {
 203         size_t len;
 204
 205         if (!buf)
 206                 return 0;
 207         len = strlen(buf);
 208         return write(fd, buf, len) != len? -E_CLIENT_WRITE: 1;
 209 }
 210
 211 __malloc static char *audiod_status_string(void)
 212 {
 213         const char *status = (audiod_status == AUDIOD_ON)?
 214                 "on" : (audiod_status == AUDIOD_OFF)? "off": "sb";
 215         return para_strdup(status);
 216 }
 217
 218 static int get_play_time_slot_num(void)
 219 {
 220         int i, oldest_slot = -1;
 221         struct timeval oldest_wstime = {0, 0};
 222
 223         FOR_EACH_SLOT(i) {
 224                 struct slot_info *s = &slot[i];
 225                 struct timeval wstime;
 226                 if (!s->wns || !s->wns[0].btrn)
 227                         continue;
 228                 btr_get_node_start(s->wns[0].btrn, &wstime);
 229                 if (oldest_slot >= 0 && tv_diff(&wstime, &oldest_wstime, NULL) > 0)
 230                         continue;
 231                 oldest_wstime = wstime;
 232                 oldest_slot = i;
 233         }
 234         //PARA_CRIT_LOG("oldest slot: %d\n", oldest_slot);
 235         return oldest_slot;
 236 }
 237
 238 __malloc static char *decoder_flags(void)
 239 {
 240         int i;
 241         char flags[MAX_STREAM_SLOTS + 1];
 242
 243         FOR_EACH_SLOT(i) {
 244                 struct slot_info *s = &slot[i];
 245                 char flag = '0';
 246                 if (s->receiver_node)
 247                         flag += 1;
 248                 if (s->fns)
 249                         flag += 2;
 250                 if (s->wns)
 251                         flag += 4;
 252                 flags[i] = flag;
 253         }
 254         flags[MAX_STREAM_SLOTS] = '\0';
 255         return para_strdup(flags);
 256 }
 257
 258 static int dump_commands(int fd)
 259 {
 260         char *buf = para_strdup(""), *tmp = NULL;
 261         int i;
 262         ssize_t ret;
 263
 264         FOR_EACH_COMMAND(i) {
 265                 tmp = make_message("%s%s\t%s\n", buf, audiod_cmds[i].name,
 266                         audiod_cmds[i].description);
 267                 free(buf);
 268                 buf = tmp;
 269         }
 270         ret = client_write(fd, buf);
 271         free(buf);
 272         return ret;
 273 }
 274
 275 /*
 276  * command handlers don't close their fd on errors (ret < 0) so that
 277  * its caller can send an error message. Otherwise (ret >= 0) it's up
 278  * to each individual command to close the fd if necessary.
 279  */
 280
 281 static int com_help(int fd, int argc, char **argv)
 282 {
 283         int i, ret;
 284         char *buf;
 285         const char *dflt = "No such command. Available commands:\n";
 286
 287         if (argc < 2) {
 288                 ret = dump_commands(fd);
 289                 goto out;
 290         }
 291         FOR_EACH_COMMAND(i) {
 292                 if (strcmp(audiod_cmds[i].name, argv[1]))
 293                         continue;
 294                 buf = make_message(
 295                         "NAME\n\t%s -- %s\n"
 296                         "SYNOPSIS\n\tpara_audioc %s\n"
 297                         "DESCRIPTION\n%s\n",
 298                         argv[1],
 299                         audiod_cmds[i].description,
 300                         audiod_cmds[i].usage,
 301                         audiod_cmds[i].help
 302                 );
 303                 ret = client_write(fd, buf);
 304                 free(buf);
 305                 goto out;
 306         }
 307         ret = client_write(fd, dflt);
 308         if (ret > 0)
 309                 ret = dump_commands(fd);
 310 out:
 311         if (ret >= 0)
 312                 close(fd);
 313         return ret;
 314 }
 315
 316 static int com_tasks(int fd, __a_unused int argc, __a_unused char **argv)
 317 {
 318         char *tl = get_task_list(&sched);
 319         int ret = 1;
 320         if (tl)
 321                 ret = client_write(fd, tl);
 322         free(tl);
 323         if (ret > 0)
 324                 close(fd);
 325         return ret;
 326 }
 327
 328 static int com_stat(int fd, int argc, char **argv)
 329 {
 330         int i, ret, parser_friendly = 0;
 331         uint64_t mask = 0;
 332         const uint64_t one = 1;
 333         struct para_buffer b = {.flags = 0};
 334
 335         ret = mark_fd_nonblocking(fd);
 336         if (ret < 0)
 337                 return ret;
 338         for (i = 1; i < argc; i++) {
 339                 const char *arg = argv[i];
 340                 if (arg[0] != '-')
 341                         break;
 342                 if (!strcmp(arg, "--")) {
 343                         i++;
 344                         break;
 345                 }
 346                 if (!strncmp(arg, "-p", 2)) {
 347                         parser_friendly = 1;
 348                         b.flags = PBF_SIZE_PREFIX;
 349                 }
 350         }
 351         if (i >= argc)
 352                 mask--; /* set all bits */
 353         for (; i < argc; i++) {
 354                 ret = stat_item_valid(argv[i]);
 355                 if (ret < 0)
 356                         return ret;
 357                 mask |= (one << ret);
 358         }
 359         PARA_INFO_LOG("mask: 0x%llx\n", (long long unsigned)mask);
 360         FOR_EACH_STATUS_ITEM(i) {
 361                 char *item = stat_item_values[i];
 362                 if (!((one << i) & mask))
 363                         continue;
 364                 (void)WRITE_STATUS_ITEM(&b, i, "%s\n", item? item : "");
 365         }
 366         ret = client_write(fd, b.buf);
 367         if (ret >= 0)
 368                 ret = stat_client_add(fd, mask, parser_friendly);
 369         free(b.buf);
 370         return ret;
 371 }
 372
 373 static int com_grab(int fd, int argc, char **argv)
 374 {
 375         return grab_client_new(fd, argc, argv, &sched);
 376 }
 377
 378 __noreturn static int com_term(int fd, __a_unused int argc, __a_unused char **argv)
 379 {
 380         close(fd);
 381         clean_exit(EXIT_SUCCESS, "terminating on user request");
 382 }
 383
 384 static int com_on(int fd, __a_unused int argc, __a_unused char **argv)
 385 {
 386         audiod_status = AUDIOD_ON;
 387         close(fd);
 388         return 1;
 389 }
 390
 391 static int com_off(int fd, __a_unused int argc, __a_unused char **argv)
 392 {
 393         audiod_status = AUDIOD_OFF;
 394         close(fd);
 395         return 1;
 396 }
 397
 398 static int com_sb(int fd, __a_unused int argc, __a_unused char **argv)
 399 {
 400         audiod_status = AUDIOD_STANDBY;
 401         close(fd);
 402         return 1;
 403 }
 404
 405 static int com_cycle(int fd, int argc, char **argv)
 406 {
 407         switch (audiod_status) {
 408                 case  AUDIOD_ON:
 409                         return com_sb(fd, argc, argv);
 410                         break;
 411                 case  AUDIOD_OFF:
 412                         return com_on(fd, argc, argv);
 413                         break;
 414                 case  AUDIOD_STANDBY:
 415                         return com_off(fd, argc, argv);
 416                         break;
 417         }
 418         close(fd);
 419         return 1;
 420 }
 421
 422 static int check_perms(uid_t uid)
 423 {
 424         int i;
 425
 426         if (!conf.user_allow_given)
 427                 return 1;
 428         for (i = 0; i < conf.user_allow_given; i++)
 429                 if (uid == conf.user_allow_arg[i])
 430                         return 1;
 431         return -E_UCRED_PERM;
 432 }
 433
 434 /**
 435  * Handle arriving connections on the local socket.
 436  *
 437  * \param accept_fd The fd to accept connections on.
 438  * \param rfds If \a accept_fd is not set in \a rfds, do nothing.
 439  *
 440  * This is called in each iteration of the select loop. If there is an incoming
 441  * connection on \a accept_fd, this function reads the command sent by the peer,
 442  * checks the connecting user's permissions by using unix socket credentials
 443  * (if supported by the OS) and calls the corresponding command handler if
 444  * permissions are OK.
 445  *
 446  * \return Positive on success, negative on errors, zero if there was no
 447  * connection to accept.
 448  *
 449  * \sa para_accept(), recv_cred_buffer()
 450  * */
 451 int handle_connect(int accept_fd, fd_set *rfds)
 452 {
 453         int i, argc, ret, clifd;
 454         char buf[MAXLINE], **argv = NULL;
 455         struct sockaddr_un unix_addr;
 456         uid_t uid;
 457
 458         ret = para_accept(accept_fd, rfds, &unix_addr, sizeof(struct sockaddr_un), &clifd);
 459         if (ret <= 0)
 460                 return ret;
 461         ret = recv_cred_buffer(clifd, buf, sizeof(buf) - 1);
 462         if (ret < 0)
 463                 goto out;
 464         uid = ret;
 465         PARA_INFO_LOG("connection from user %i, buf: %s\n",  ret, buf);
 466         ret = check_perms(uid);
 467         if (ret < 0)
 468                 goto out;
 469         ret = create_argv(buf, "\n", &argv);
 470         if (ret <= 0)
 471                 goto out;
 472         argc = ret;
 473         //PARA_INFO_LOG("argv[0]: %s, argc = %d\n", argv[0], argc);
 474         FOR_EACH_COMMAND(i) {
 475                 if (strcmp(audiod_cmds[i].name, argv[0]))
 476                         continue;
 477                 ret = audiod_cmds[i].handler(clifd, argc, argv);
 478                 goto out;
 479         }
 480         ret = -E_INVALID_AUDIOD_CMD;
 481 out:
 482         free_argv(argv);
 483         if (clifd > 0 && ret < 0 && ret != -E_CLIENT_WRITE) {
 484                 char *tmp = make_message("%s\n", para_strerror(-ret));
 485                 client_write(clifd, tmp);
 486                 free(tmp);
 487                 close(clifd);
 488         }
 489         return ret;
 490 }
 491
 492 /**
 493  * Send the current audiod status to all connected stat clients.
 494  *
 495  * \param force Whether to write unchanged items.
 496  */
 497 void audiod_status_dump(bool force)
 498 {
 499         int slot_num = get_play_time_slot_num();
 500         char *old, *new;
 501
 502         old = stat_item_values[SI_PLAY_TIME];
 503         new = get_time_string(slot_num);
 504         if (new) {
 505                 if (force || !old || strcmp(old, new)) {
 506                         free(old);
 507                         stat_item_values[SI_PLAY_TIME] = new;
 508                         stat_client_write_item(SI_PLAY_TIME);
 509                 } else
 510                         free(new);
 511         }
 512
 513         new = get_server_uptime_str(now);
 514         old = stat_item_values[SI_AUDIOD_UPTIME];
 515         if (force || !old || strcmp(old, new)) {
 516                 free(old);
 517                 stat_item_values[SI_AUDIOD_UPTIME] = new;
 518                 stat_client_write_item(SI_AUDIOD_UPTIME);
 519         } else
 520                 free(new);
 521
 522         old = stat_item_values[SI_AUDIOD_STATUS];
 523         new = audiod_status_string();
 524         if (force || !old || strcmp(old, new)) {
 525                 free(old);
 526                 stat_item_values[SI_AUDIOD_STATUS] = new;
 527                 stat_client_write_item(SI_AUDIOD_STATUS);
 528         } else
 529                 free(new);
 530
 531         old = stat_item_values[SI_DECODER_FLAGS];
 532         new = decoder_flags();
 533         if (force || !old || strcmp(old, new)) {
 534                 free(old);
 535                 stat_item_values[SI_DECODER_FLAGS] = new;
 536                 stat_client_write_item(SI_DECODER_FLAGS);
 537         } else
 538                 free(new);
 539 }
 540
 541 /**
 542  * Flush and send all status items.
 543  *
 544  * Send to  each connected client the full status item list
 545  * with empty values.
 546  */
 547 void clear_and_dump_items(void)
 548 {
 549         int i;
 550
 551         FOR_EACH_STATUS_ITEM(i) {
 552                 free(stat_item_values[i]);
 553                 stat_item_values[i] = NULL;
 554                 stat_client_write_item(i);
 555         }
 556 }