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 <regex.h>
  10 #include <sys/types.h>
  11
  12 #include "para.h"
  13 #include "audiod.cmdline.h"
  14 #include "list.h"
  15 #include "sched.h"
  16 #include "ggo.h"
  17 #include "buffer_tree.h"
  18 #include "filter.h"
  19 #include "grab_client.h"
  20 #include "error.h"
  21 #include "audiod.h"
  22 #include "net.h"
  23 #include "daemon.h"
  24 #include "string.h"
  25 #include "write.h"
  26 #include "fd.h"
  27 #include "audiod_command_list.h"
  28
  29 extern struct sched sched;
  30 extern char *stat_item_values[NUM_STAT_ITEMS];
  31
  32
  33 static struct audiod_command audiod_cmds[] = {DEFINE_AUDIOD_CMD_ARRAY};
  34
  35 /** Iterate over the array of all audiod commands. */
  36 #define FOR_EACH_COMMAND(c) for (c = 0; audiod_cmds[c].name; c++)
  37
  38 /** The maximal number of simultaneous connections. */
  39 #define MAX_STAT_CLIENTS 50
  40
  41 /** Flags used for the stat command of para_audiod. */
  42 enum stat_client_flags {
  43         /** Enable parser-friendly output. */
  44         SCF_PARSER_FRIENDLY = 1,
  45 };
  46
  47 /**
  48  * Describes a status client of para_audiod.
  49  *
  50  * There's one such structure per audiod client that sent the 'stat' command.
  51  *
  52  * A status client is identified by its file descriptor.  para_audiod
  53  * keeps a list of connected status clients.
  54  */
  55 struct stat_client {
  56         /** The stat client's file descriptor. */
  57         int fd;
  58         /** Bitmask of those status items the client is interested in. */
  59         uint64_t item_mask;
  60         /** See \ref stat_client flags. s*/
  61         unsigned flags;
  62         /** Its entry in the list of stat clients. */
  63         struct list_head node;
  64 };
  65
  66 static INITIALIZED_LIST_HEAD(client_list);
  67 static int num_clients;
  68
  69 /** The list of all status items used by para_{server,audiod,gui}. */
  70 const char *status_item_list[] = {STATUS_ITEM_ARRAY};
  71
  72 static void dump_stat_client_list(void)
  73 {
  74         struct stat_client *sc;
  75
  76         list_for_each_entry(sc, &client_list, node)
  77                 PARA_INFO_LOG("stat client on fd %d\n", sc->fd);
  78 }
  79 /**
  80  * Add a status client to the list.
  81  *
  82  * \param fd The file descriptor of the client.
  83  * \param mask Bitfield of status items for this client.
  84  * \param parser_friendly Enable parser-friendly output mode.
  85  *
  86  * Only those status items having the bit set in \a mask will be
  87  * sent to the client.
  88  *
  89  * \return Positive value on success, or -E_TOO_MANY_CLIENTS if
  90  * the number of connected clients exceeds #MAX_STAT_CLIENTS.
  91  */
  92 static int stat_client_add(int fd, uint64_t mask, int parser_friendly)
  93 {
  94         struct stat_client *new_client;
  95
  96         if (num_clients >= MAX_STAT_CLIENTS) {
  97                 PARA_ERROR_LOG("maximal number of stat clients (%d) exceeded\n",
  98                         MAX_STAT_CLIENTS);
  99                 return -E_TOO_MANY_CLIENTS;
 100         }
 101         PARA_INFO_LOG("adding client on fd %d\n", fd);
 102         new_client = para_calloc(sizeof(struct stat_client));
 103         new_client->fd = fd;
 104         new_client->item_mask = mask;
 105         if (parser_friendly)
 106                 new_client->flags = SCF_PARSER_FRIENDLY;
 107         para_list_add(&new_client->node, &client_list);
 108         dump_stat_client_list();
 109         num_clients++;
 110         return 1;
 111 }
 112
 113 static void close_stat_client(struct stat_client *sc)
 114 {
 115         PARA_INFO_LOG("closing client fd %d\n", sc->fd);
 116         close(sc->fd);
 117         list_del(&sc->node);
 118         free(sc);
 119         num_clients--;
 120 }
 121
 122 /**
 123  * Empty the status clients list.
 124  *
 125  * This iterates over the list of connected status clients, closes each client
 126  * file descriptor and frees the resources.
 127  */
 128 void close_stat_clients(void)
 129 {
 130         struct stat_client *sc, *tmp;
 131
 132         list_for_each_entry_safe(sc, tmp, &client_list, node)
 133                 close_stat_client(sc);
 134         assert(num_clients == 0);
 135 }
 136
 137 /**
 138  * Write a message to all connected status clients.
 139  *
 140  * \param item_num The number of the status item of \a msg.
 141  *
 142  * On write errors, remove the status client from the client list and close its
 143  * file descriptor.
 144  */
 145 void stat_client_write_item(int item_num)
 146 {
 147         struct stat_client *sc, *tmp;
 148         struct para_buffer pb = {.flags = 0};
 149         struct para_buffer pfpb = {.flags = PBF_SIZE_PREFIX};
 150         const uint64_t one = 1;
 151         char *msg = stat_item_values[item_num];
 152         struct para_buffer *b;
 153
 154         list_for_each_entry_safe(sc, tmp, &client_list, node) {
 155                 int ret;
 156
 157                 if (!((one << item_num) & sc->item_mask))
 158                         continue;
 159                 b = (sc->flags & SCF_PARSER_FRIENDLY)? &pfpb : &pb;
 160                 if (!b->buf)
 161                         (void)WRITE_STATUS_ITEM(b, item_num, "%s\n",
 162                                 msg? msg : "");
 163                 ret = write(sc->fd, b->buf, b->offset);
 164                 if (ret == b->offset)
 165                         continue;
 166                 /* write error or short write */
 167                 close_stat_client(sc);
 168                 dump_stat_client_list();
 169         }
 170         free(pb.buf);
 171         free(pfpb.buf);
 172 }
 173
 174 /**
 175  * Check if string is a known status item.
 176  *
 177  * \param item Buffer containing the text to check.
 178  *
 179  * \return If \a item is a valid status item, the number of that status item is
 180  * returned. Otherwise, this function returns \p -E_UNKNOWN_STAT_ITEM.
 181  */
 182 static int stat_item_valid(const char *item)
 183 {
 184         int i;
 185         if (!item || !*item) {
 186                 PARA_ERROR_LOG("%s\n", "no item");
 187                 return -E_UNKNOWN_STAT_ITEM;
 188         }
 189         FOR_EACH_STATUS_ITEM(i)
 190                 if (!strcmp(status_item_list[i], item))
 191                         return i;
 192         PARA_ERROR_LOG("invalid stat item: %s\n", item);
 193         return -E_UNKNOWN_STAT_ITEM;
 194 }
 195
 196 static int client_write(int fd, const char *buf)
 197 {
 198         size_t len;
 199
 200         if (!buf)
 201                 return 0;
 202         len = strlen(buf);
 203         return write(fd, buf, len) != len? -E_CLIENT_WRITE: 1;
 204 }
 205
 206 __malloc static char *audiod_status_string(void)
 207 {
 208         const char *status = (audiod_status == AUDIOD_ON)?
 209                 "on" : (audiod_status == AUDIOD_OFF)? "off": "sb";
 210         return para_strdup(status);
 211 }
 212
 213 static int get_play_time_slot_num(void)
 214 {
 215         int i, oldest_slot = -1;
 216         struct timeval oldest_wstime = {0, 0};
 217
 218         FOR_EACH_SLOT(i) {
 219                 struct slot_info *s = &slot[i];
 220                 struct timeval wstime;
 221                 if (!s->wns || !s->wns[0].btrn)
 222                         continue;
 223                 btr_get_node_start(s->wns[0].btrn, &wstime);
 224                 if (oldest_slot >= 0 && tv_diff(&wstime, &oldest_wstime, NULL) > 0)
 225                         continue;
 226                 oldest_wstime = wstime;
 227                 oldest_slot = i;
 228         }
 229         //PARA_CRIT_LOG("oldest slot: %d\n", oldest_slot);
 230         return oldest_slot;
 231 }
 232
 233 __malloc static char *decoder_flags(void)
 234 {
 235         int i;
 236         char flags[MAX_STREAM_SLOTS + 1];
 237
 238         FOR_EACH_SLOT(i) {
 239                 struct slot_info *s = &slot[i];
 240                 char flag = '0';
 241                 if (s->receiver_node)
 242                         flag += 1;
 243                 if (s->fns)
 244                         flag += 2;
 245                 if (s->wns)
 246                         flag += 4;
 247                 flags[i] = flag;
 248         }
 249         flags[MAX_STREAM_SLOTS] = '\0';
 250         return para_strdup(flags);
 251 }
 252
 253 static int dump_commands(int fd)
 254 {
 255         char *buf = para_strdup(""), *tmp = NULL;
 256         int i;
 257         ssize_t ret;
 258
 259         FOR_EACH_COMMAND(i) {
 260                 tmp = make_message("%s%s\t%s\n", buf, audiod_cmds[i].name,
 261                         audiod_cmds[i].description);
 262                 free(buf);
 263                 buf = tmp;
 264         }
 265         ret = client_write(fd, buf);
 266         free(buf);
 267         return ret;
 268 }
 269
 270 /*
 271  * command handlers don't close their fd on errors (ret < 0) so that
 272  * its caller can send an error message. Otherwise (ret >= 0) it's up
 273  * to each individual command to close the fd if necessary.
 274  */
 275
 276 static int com_help(int fd, int argc, char **argv)
 277 {
 278         int i, ret;
 279         char *buf;
 280         const char *dflt = "No such command. Available commands:\n";
 281
 282         if (argc < 2) {
 283                 ret = dump_commands(fd);
 284                 goto out;
 285         }
 286         FOR_EACH_COMMAND(i) {
 287                 if (strcmp(audiod_cmds[i].name, argv[1]))
 288                         continue;
 289                 buf = make_message(
 290                         "NAME\n\t%s -- %s\n"
 291                         "SYNOPSIS\n\tpara_audioc %s\n"
 292                         "DESCRIPTION\n%s\n",
 293                         argv[1],
 294                         audiod_cmds[i].description,
 295                         audiod_cmds[i].usage,
 296                         audiod_cmds[i].help
 297                 );
 298                 ret = client_write(fd, buf);
 299                 free(buf);
 300                 goto out;
 301         }
 302         ret = client_write(fd, dflt);
 303         if (ret > 0)
 304                 ret = dump_commands(fd);
 305 out:
 306         if (ret >= 0)
 307                 close(fd);
 308         return ret;
 309 }
 310
 311 static int com_tasks(int fd, __a_unused int argc, __a_unused char **argv)
 312 {
 313         char *tl = get_task_list(&sched);
 314         int ret = 1;
 315         if (tl)
 316                 ret = client_write(fd, tl);
 317         free(tl);
 318         if (ret > 0)
 319                 close(fd);
 320         return ret;
 321 }
 322
 323 static int com_stat(int fd, int argc, char **argv)
 324 {
 325         int i, ret, parser_friendly = 0;
 326         uint64_t mask = 0;
 327         const uint64_t one = 1;
 328         struct para_buffer b = {.flags = 0};
 329
 330         ret = mark_fd_nonblocking(fd);
 331         if (ret < 0)
 332                 return ret;
 333         for (i = 1; i < argc; i++) {
 334                 const char *arg = argv[i];
 335                 if (arg[0] != '-')
 336                         break;
 337                 if (!strcmp(arg, "--")) {
 338                         i++;
 339                         break;
 340                 }
 341                 if (!strncmp(arg, "-p", 2)) {
 342                         parser_friendly = 1;
 343                         b.flags = PBF_SIZE_PREFIX;
 344                 }
 345         }
 346         if (i >= argc)
 347                 mask--; /* set all bits */
 348         for (; i < argc; i++) {
 349                 ret = stat_item_valid(argv[i]);
 350                 if (ret < 0)
 351                         return ret;
 352                 mask |= (one << ret);
 353         }
 354         PARA_INFO_LOG("mask: 0x%llx\n", (long long unsigned)mask);
 355         FOR_EACH_STATUS_ITEM(i) {
 356                 char *item = stat_item_values[i];
 357                 if (!((one << i) & mask))
 358                         continue;
 359                 (void)WRITE_STATUS_ITEM(&b, i, "%s\n", item? item : "");
 360         }
 361         ret = client_write(fd, b.buf);
 362         if (ret >= 0)
 363                 ret = stat_client_add(fd, mask, parser_friendly);
 364         free(b.buf);
 365         return ret;
 366 }
 367
 368 static int com_grab(int fd, int argc, char **argv)
 369 {
 370         return grab_client_new(fd, argc, argv, &sched);
 371 }
 372
 373 __noreturn static int com_term(int fd, __a_unused int argc, __a_unused char **argv)
 374 {
 375         close(fd);
 376         clean_exit(EXIT_SUCCESS, "terminating on user request");
 377 }
 378
 379 static int com_on(int fd, __a_unused int argc, __a_unused char **argv)
 380 {
 381         audiod_status = AUDIOD_ON;
 382         close(fd);
 383         return 1;
 384 }
 385
 386 static int com_off(int fd, __a_unused int argc, __a_unused char **argv)
 387 {
 388         audiod_status = AUDIOD_OFF;
 389         close(fd);
 390         return 1;
 391 }
 392
 393 static int com_sb(int fd, __a_unused int argc, __a_unused char **argv)
 394 {
 395         audiod_status = AUDIOD_STANDBY;
 396         close(fd);
 397         return 1;
 398 }
 399
 400 static int com_cycle(int fd, int argc, char **argv)
 401 {
 402         switch (audiod_status) {
 403                 case  AUDIOD_ON:
 404                         return com_sb(fd, argc, argv);
 405                         break;
 406                 case  AUDIOD_OFF:
 407                         return com_on(fd, argc, argv);
 408                         break;
 409                 case  AUDIOD_STANDBY:
 410                         return com_off(fd, argc, argv);
 411                         break;
 412         }
 413         close(fd);
 414         return 1;
 415 }
 416
 417 static int check_perms(uid_t uid)
 418 {
 419         int i;
 420
 421         if (!conf.user_allow_given)
 422                 return 1;
 423         for (i = 0; i < conf.user_allow_given; i++)
 424                 if (uid == conf.user_allow_arg[i])
 425                         return 1;
 426         return -E_UCRED_PERM;
 427 }
 428
 429 /**
 430  * Handle arriving connections on the local socket.
 431  *
 432  * \param accept_fd The fd to accept connections on.
 433  * \param rfds If \a accept_fd is not set in \a rfds, do nothing.
 434  *
 435  * This is called in each iteration of the select loop. If there is an incoming
 436  * connection on \a accept_fd, this function reads the command sent by the peer,
 437  * checks the connecting user's permissions by using unix socket credentials
 438  * (if supported by the OS) and calls the corresponding command handler if
 439  * permissions are OK.
 440  *
 441  * \return Positive on success, negative on errors, zero if there was no
 442  * connection to accept.
 443  *
 444  * \sa para_accept(), recv_cred_buffer()
 445  * */
 446 int handle_connect(int accept_fd, fd_set *rfds)
 447 {
 448         int i, argc, ret, clifd;
 449         char buf[MAXLINE], **argv = NULL;
 450         struct sockaddr_un unix_addr;
 451         uid_t uid;
 452
 453         ret = para_accept(accept_fd, rfds, &unix_addr, sizeof(struct sockaddr_un), &clifd);
 454         if (ret <= 0)
 455                 return ret;
 456         ret = recv_cred_buffer(clifd, buf, sizeof(buf) - 1);
 457         if (ret < 0)
 458                 goto out;
 459         uid = ret;
 460         PARA_INFO_LOG("connection from user %i, buf: %s\n",  ret, buf);
 461         ret = check_perms(uid);
 462         if (ret < 0)
 463                 goto out;
 464         ret = create_argv(buf, "\n", &argv);
 465         if (ret <= 0)
 466                 goto out;
 467         argc = ret;
 468         //PARA_INFO_LOG("argv[0]: %s, argc = %d\n", argv[0], argc);
 469         FOR_EACH_COMMAND(i) {
 470                 if (strcmp(audiod_cmds[i].name, argv[0]))
 471                         continue;
 472                 ret = audiod_cmds[i].handler(clifd, argc, argv);
 473                 goto out;
 474         }
 475         ret = -E_INVALID_AUDIOD_CMD;
 476 out:
 477         free_argv(argv);
 478         if (clifd > 0 && ret < 0 && ret != -E_CLIENT_WRITE) {
 479                 char *tmp = make_message("%s\n", para_strerror(-ret));
 480                 client_write(clifd, tmp);
 481                 free(tmp);
 482                 close(clifd);
 483         }
 484         return ret;
 485 }
 486
 487 /**
 488  * Send the current audiod status to all connected stat clients.
 489  *
 490  * \param force Whether to write unchanged items.
 491  */
 492 void audiod_status_dump(bool force)
 493 {
 494         int slot_num = get_play_time_slot_num();
 495         char *old, *new;
 496
 497         old = stat_item_values[SI_PLAY_TIME];
 498         new = get_time_string(slot_num);
 499         if (new) {
 500                 if (force || !old || strcmp(old, new)) {
 501                         free(old);
 502                         stat_item_values[SI_PLAY_TIME] = new;
 503                         stat_client_write_item(SI_PLAY_TIME);
 504                 } else
 505                         free(new);
 506         }
 507
 508         new = get_server_uptime_str(now);
 509         old = stat_item_values[SI_AUDIOD_UPTIME];
 510         if (force || !old || strcmp(old, new)) {
 511                 free(old);
 512                 stat_item_values[SI_AUDIOD_UPTIME] = new;
 513                 stat_client_write_item(SI_AUDIOD_UPTIME);
 514         } else
 515                 free(new);
 516
 517         old = stat_item_values[SI_AUDIOD_STATUS];
 518         new = audiod_status_string();
 519         if (force || !old || strcmp(old, new)) {
 520                 free(old);
 521                 stat_item_values[SI_AUDIOD_STATUS] = new;
 522                 stat_client_write_item(SI_AUDIOD_STATUS);
 523         } else
 524                 free(new);
 525
 526         old = stat_item_values[SI_DECODER_FLAGS];
 527         new = decoder_flags();
 528         if (force || !old || strcmp(old, new)) {
 529                 free(old);
 530                 stat_item_values[SI_DECODER_FLAGS] = new;
 531                 stat_client_write_item(SI_DECODER_FLAGS);
 532         } else
 533                 free(new);
 534 }
 535
 536 /**
 537  * Flush and send all status items.
 538  *
 539  * Send to  each connected client the full status item list
 540  * with empty values.
 541  */
 542 void clear_and_dump_items(void)
 543 {
 544         int i;
 545
 546         FOR_EACH_STATUS_ITEM(i) {
 547                 free(stat_item_values[i]);
 548                 stat_item_values[i] = NULL;
 549                 stat_client_write_item(i);
 550         }
 551 }