audiod_command.c

   1 /*
   2  * Copyright (C) 2005-2012 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 /** Iterate over the array of all audiod commands. */
  33 #define FOR_EACH_COMMAND(c) for (c = 0; audiod_cmds[c].name; c++)
  34
  35 /** The maximal number of simultaneous connections. */
  36 #define MAX_STAT_CLIENTS 50
  37
  38 /** Flags used for the stat command of para_audiod. */
  39 enum stat_client_flags {
  40         /** Enable parser-friendly output. */
  41         SCF_PARSER_FRIENDLY = 1,
  42 };
  43
  44 /**
  45  * Describes a status client of para_audiod.
  46  *
  47  * There's one such structure per audiod client that sent the 'stat' command.
  48  *
  49  * A status client is identified by its file descriptor.  para_audiod
  50  * keeps a list of connected status clients.
  51  */
  52 struct stat_client {
  53         /** The stat client's file descriptor. */
  54         int fd;
  55         /** Bitmask of those status items the client is interested in. */
  56         uint64_t item_mask;
  57         /** See \ref stat_client flags. s*/
  58         unsigned flags;
  59         /** Its entry in the list of stat clients. */
  60         struct list_head node;
  61 };
  62
  63 static INITIALIZED_LIST_HEAD(client_list);
  64 static int num_clients;
  65
  66 /** The list of all status items used by para_{server,audiod,gui}. */
  67 const char *status_item_list[] = {STATUS_ITEM_ARRAY};
  68
  69 static void dump_stat_client_list(void)
  70 {
  71         struct stat_client *sc;
  72
  73         list_for_each_entry(sc, &client_list, node)
  74                 PARA_INFO_LOG("stat client on fd %d\n", sc->fd);
  75 }
  76 /**
  77  * Add a status client to the list.
  78  *
  79  * \param fd The file descriptor of the client.
  80  * \param mask Bitfield of status items for this client.
  81  * \param parser_friendly Enable parser-friendly output mode.
  82  *
  83  * Only those status items having the bit set in \a mask will be
  84  * sent to the client.
  85  *
  86  * \return Positive value on success, or -E_TOO_MANY_CLIENTS if
  87  * the number of connected clients exceeds #MAX_STAT_CLIENTS.
  88  */
  89 static int stat_client_add(int fd, uint64_t mask, int parser_friendly)
  90 {
  91         struct stat_client *new_client;
  92
  93         if (num_clients >= MAX_STAT_CLIENTS) {
  94                 PARA_ERROR_LOG("maximal number of stat clients (%d) exceeded\n",
  95                         MAX_STAT_CLIENTS);
  96                 return -E_TOO_MANY_CLIENTS;
  97         }
  98         PARA_INFO_LOG("adding client on fd %d\n", fd);
  99         new_client = para_calloc(sizeof(struct stat_client));
 100         new_client->fd = fd;
 101         new_client->item_mask = mask;
 102         if (parser_friendly)
 103                 new_client->flags = SCF_PARSER_FRIENDLY;
 104         para_list_add(&new_client->node, &client_list);
 105         dump_stat_client_list();
 106         num_clients++;
 107         return 1;
 108 }
 109 /**
 110  * Write a message to all connected status clients.
 111  *
 112  * \param item_num The number of the status item of \a msg.
 113  *
 114  * On write errors, remove the status client from the client list and close its
 115  * file descriptor.
 116  */
 117 void stat_client_write_item(int item_num)
 118 {
 119         struct stat_client *sc, *tmp;
 120         struct para_buffer pb = {.flags = 0};
 121         struct para_buffer pfpb = {.flags = PBF_SIZE_PREFIX};
 122         const uint64_t one = 1;
 123         char *msg = stat_item_values[item_num];
 124         struct para_buffer *b;
 125
 126         list_for_each_entry_safe(sc, tmp, &client_list, node) {
 127                 int fd = sc->fd, ret;
 128
 129                 if (!((one << item_num) & sc->item_mask))
 130                         continue;
 131                 b = (sc->flags & SCF_PARSER_FRIENDLY)? &pfpb : &pb;
 132                 if (!b->buf)
 133                         (void)WRITE_STATUS_ITEM(b, item_num, "%s\n",
 134                                 msg? msg : "");
 135                 ret = write(fd, b->buf, b->offset);
 136                 if (ret == b->offset)
 137                         continue;
 138                 /* write error or short write */
 139                 close(fd);
 140                 num_clients--;
 141                 PARA_INFO_LOG("deleting client on fd %d\n", fd);
 142                 list_del(&sc->node);
 143                 free(sc);
 144                 dump_stat_client_list();
 145         }
 146         free(pb.buf);
 147         free(pfpb.buf);
 148 }
 149
 150 /**
 151  * Check if string is a known status item.
 152  *
 153  * \param item Buffer containing the text to check.
 154  *
 155  * \return If \a item is a valid status item, the number of that status item is
 156  * returned. Otherwise, this function returns \p -E_UNKNOWN_STAT_ITEM.
 157  */
 158 static int stat_item_valid(const char *item)
 159 {
 160         int i;
 161         if (!item || !*item) {
 162                 PARA_ERROR_LOG("%s\n", "no item");
 163                 return -E_UNKNOWN_STAT_ITEM;
 164         }
 165         FOR_EACH_STATUS_ITEM(i)
 166                 if (!strcmp(status_item_list[i], item))
 167                         return i;
 168         PARA_ERROR_LOG("invalid stat item: %s\n", item);
 169         return -E_UNKNOWN_STAT_ITEM;
 170 }
 171
 172 static int client_write(int fd, const char *buf)
 173 {
 174         size_t len;
 175
 176         if (!buf)
 177                 return 0;
 178         len = strlen(buf);
 179         return write(fd, buf, len) != len? -E_CLIENT_WRITE: 1;
 180 }
 181
 182 __malloc static char *audiod_status_string(void)
 183 {
 184         const char *status = (audiod_status == AUDIOD_ON)?
 185                 "on" : (audiod_status == AUDIOD_OFF)? "off": "sb";
 186         return para_strdup(status);
 187 }
 188
 189 static int get_play_time_slot_num(void)
 190 {
 191         int i, oldest_slot = -1;
 192         struct timeval oldest_wstime = {0, 0};
 193
 194         FOR_EACH_SLOT(i) {
 195                 struct slot_info *s = &slot[i];
 196                 struct timeval wstime;
 197                 if (!s->wns || !s->wns[0].btrn)
 198                         continue;
 199                 btr_get_node_start(s->wns[0].btrn, &wstime);
 200                 if (oldest_slot >= 0 && tv_diff(&wstime, &oldest_wstime, NULL) > 0)
 201                         continue;
 202                 oldest_wstime = wstime;
 203                 oldest_slot = i;
 204         }
 205         //PARA_CRIT_LOG("oldest slot: %d\n", oldest_slot);
 206         return oldest_slot;
 207 }
 208
 209 __malloc static char *decoder_flags(void)
 210 {
 211         int i;
 212         char flags[MAX_STREAM_SLOTS + 1];
 213
 214         FOR_EACH_SLOT(i) {
 215                 struct slot_info *s = &slot[i];
 216                 char flag = '0';
 217                 if (s->receiver_node)
 218                         flag += 1;
 219                 if (s->fns)
 220                         flag += 2;
 221                 if (s->wns)
 222                         flag += 4;
 223                 flags[i] = flag;
 224         }
 225         flags[MAX_STREAM_SLOTS] = '\0';
 226         return para_strdup(flags);
 227 }
 228
 229 static int dump_commands(int fd)
 230 {
 231         char *buf = para_strdup(""), *tmp = NULL;
 232         int i;
 233         ssize_t ret;
 234
 235         FOR_EACH_COMMAND(i) {
 236                 tmp = make_message("%s%s\t%s\n", buf, audiod_cmds[i].name,
 237                         audiod_cmds[i].description);
 238                 free(buf);
 239                 buf = tmp;
 240         }
 241         ret = client_write(fd, buf);
 242         free(buf);
 243         return ret;
 244 }
 245
 246 /*
 247  * command handlers don't close their fd on errors (ret < 0) so that
 248  * its caller can send an error message. Otherwise (ret >= 0) it's up
 249  * to each individual command to close the fd if necessary.
 250  */
 251
 252 int com_help(int fd, int argc, char **argv)
 253 {
 254         int i, ret;
 255         char *buf;
 256         const char *dflt = "No such command. Available commands:\n";
 257
 258         if (argc < 2) {
 259                 ret = dump_commands(fd);
 260                 goto out;
 261         }
 262         FOR_EACH_COMMAND(i) {
 263                 if (strcmp(audiod_cmds[i].name, argv[1]))
 264                         continue;
 265                 buf = make_message(
 266                         "NAME\n\t%s -- %s\n"
 267                         "SYNOPSIS\n\tpara_audioc %s\n"
 268                         "DESCRIPTION\n%s\n",
 269                         argv[1],
 270                         audiod_cmds[i].description,
 271                         audiod_cmds[i].usage,
 272                         audiod_cmds[i].help
 273                 );
 274                 ret = client_write(fd, buf);
 275                 free(buf);
 276                 goto out;
 277         }
 278         ret = client_write(fd, dflt);
 279         if (ret > 0)
 280                 ret = dump_commands(fd);
 281 out:
 282         if (ret >= 0)
 283                 close(fd);
 284         return ret;
 285 }
 286
 287 int com_tasks(int fd, __a_unused int argc, __a_unused char **argv)
 288 {
 289         char *tl = get_task_list(&sched);
 290         int ret = 1;
 291         if (tl)
 292                 ret = client_write(fd, tl);
 293         free(tl);
 294         if (ret > 0)
 295                 close(fd);
 296         return ret;
 297 }
 298
 299 int com_stat(int fd, int argc, char **argv)
 300 {
 301         int i, ret, parser_friendly = 0;
 302         uint64_t mask = 0;
 303         const uint64_t one = 1;
 304         struct para_buffer b = {.flags = 0};
 305
 306         ret = mark_fd_nonblocking(fd);
 307         if (ret < 0)
 308                 return ret;
 309         for (i = 1; i < argc; i++) {
 310                 const char *arg = argv[i];
 311                 if (arg[0] != '-')
 312                         break;
 313                 if (!strcmp(arg, "--")) {
 314                         i++;
 315                         break;
 316                 }
 317                 if (!strncmp(arg, "-p", 2)) {
 318                         parser_friendly = 1;
 319                         b.flags = PBF_SIZE_PREFIX;
 320                         continue;
 321                 }
 322         }
 323         if (i >= argc)
 324                 mask--; /* set all bits */
 325         for (; i < argc; i++) {
 326                 ret = stat_item_valid(argv[i]);
 327                 if (ret < 0)
 328                         return ret;
 329                 mask |= (one << ret);
 330         }
 331         PARA_INFO_LOG("mask: 0x%llx\n", (long long unsigned)mask);
 332         FOR_EACH_STATUS_ITEM(i) {
 333                 char *item = stat_item_values[i];
 334                 if (!((one << i) & mask))
 335                         continue;
 336                 (void)WRITE_STATUS_ITEM(&b, i, "%s\n", item? item : "");
 337         }
 338         ret = client_write(fd, b.buf);
 339         if (ret >= 0)
 340                 ret = stat_client_add(fd, mask, parser_friendly);
 341         free(b.buf);
 342         return ret;
 343 }
 344
 345 int com_grab(int fd, int argc, char **argv)
 346 {
 347         return grab_client_new(fd, argc, argv, &sched);
 348 }
 349
 350 __noreturn int com_term(int fd, __a_unused int argc, __a_unused char **argv)
 351 {
 352         close(fd);
 353         clean_exit(EXIT_SUCCESS, "terminating on user request");
 354 }
 355
 356 int com_on(int fd, __a_unused int argc, __a_unused char **argv)
 357 {
 358         audiod_status = AUDIOD_ON;
 359         close(fd);
 360         return 1;
 361 }
 362
 363 int com_off(int fd, __a_unused int argc, __a_unused char **argv)
 364 {
 365         audiod_status = AUDIOD_OFF;
 366         close(fd);
 367         return 1;
 368 }
 369
 370 int com_sb(int fd, __a_unused int argc, __a_unused char **argv)
 371 {
 372         audiod_status = AUDIOD_STANDBY;
 373         close(fd);
 374         return 1;
 375 }
 376
 377 int com_cycle(int fd, int argc, char **argv)
 378 {
 379         switch (audiod_status) {
 380                 case  AUDIOD_ON:
 381                         return com_sb(fd, argc, argv);
 382                         break;
 383                 case  AUDIOD_OFF:
 384                         return com_on(fd, argc, argv);
 385                         break;
 386                 case  AUDIOD_STANDBY:
 387                         return com_off(fd, argc, argv);
 388                         break;
 389         }
 390         close(fd);
 391         return 1;
 392 }
 393
 394 static int check_perms(uid_t uid)
 395 {
 396         int i;
 397
 398         if (!conf.user_allow_given)
 399                 return 1;
 400         for (i = 0; i < conf.user_allow_given; i++)
 401                 if (uid == conf.user_allow_arg[i])
 402                         return 1;
 403         return -E_UCRED_PERM;
 404 }
 405
 406 /**
 407  * Handle arriving connections on the local socket.
 408  *
 409  * \param accept_fd The fd to accept connections on.
 410  * \param rfds If \a accept_fd is not set in \a rfds, do nothing.
 411  *
 412  * This is called in each iteration of the select loop. If there is an incoming
 413  * connection on \a accept_fd, this function reads the command sent by the peer,
 414  * checks the connecting user's permissions by using unix socket credentials
 415  * (if supported by the OS) and calls the corresponding command handler if
 416  * permissions are OK.
 417  *
 418  * \return Positive on success, negative on errors, zero if there was no
 419  * connection to accept.
 420  *
 421  * \sa para_accept(), recv_cred_buffer()
 422  * */
 423 int handle_connect(int accept_fd, fd_set *rfds)
 424 {
 425         int i, argc, ret, clifd;
 426         char buf[MAXLINE], **argv = NULL;
 427         struct sockaddr_un unix_addr;
 428         uid_t uid;
 429
 430         ret = para_accept(accept_fd, rfds, &unix_addr, sizeof(struct sockaddr_un), &clifd);
 431         if (ret <= 0)
 432                 return ret;
 433         ret = recv_cred_buffer(clifd, buf, sizeof(buf) - 1);
 434         if (ret < 0)
 435                 goto out;
 436         uid = ret;
 437         PARA_INFO_LOG("connection from user %i, buf: %s\n",  ret, buf);
 438         ret = check_perms(uid);
 439         if (ret < 0)
 440                 goto out;
 441         ret = create_argv(buf, "\n", &argv);
 442         if (ret < 0)
 443                 goto out;
 444         argc = ret;
 445         //PARA_INFO_LOG("argv[0]: %s, argc = %d\n", argv[0], argc);
 446         FOR_EACH_COMMAND(i) {
 447                 if (strcmp(audiod_cmds[i].name, argv[0]))
 448                         continue;
 449                 ret = audiod_cmds[i].handler(clifd, argc, argv);
 450                 goto out;
 451         }
 452         ret = -E_INVALID_AUDIOD_CMD;
 453 out:
 454         free_argv(argv);
 455         if (clifd > 0 && ret < 0 && ret != -E_CLIENT_WRITE) {
 456                 char *tmp = make_message("%s\n", para_strerror(-ret));
 457                 client_write(clifd, tmp);
 458                 free(tmp);
 459                 close(clifd);
 460         }
 461         return ret;
 462 }
 463
 464 /**
 465  * Send the current audiod status to all connected stat clients.
 466  */
 467 void audiod_status_dump(void)
 468 {
 469         int slot_num = get_play_time_slot_num();
 470         char *old, *new;
 471
 472         old = stat_item_values[SI_PLAY_TIME];
 473         new = get_time_string(slot_num);
 474         if (new) {
 475                 if (!old || strcmp(old, new)) {
 476                         free(old);
 477                         stat_item_values[SI_PLAY_TIME] = new;
 478                         stat_client_write_item(SI_PLAY_TIME);
 479                 } else
 480                         free(new);
 481         }
 482
 483         new = get_server_uptime_str(now);
 484         old = stat_item_values[SI_AUDIOD_UPTIME];
 485         if (!old || strcmp(old, new)) {
 486                 free(old);
 487                 stat_item_values[SI_AUDIOD_UPTIME] = new;
 488                 stat_client_write_item(SI_AUDIOD_UPTIME);
 489         } else
 490                 free(new);
 491
 492         old = stat_item_values[SI_AUDIOD_STATUS];
 493         new = audiod_status_string();
 494         if (!old || strcmp(old, new)) {
 495                 free(old);
 496                 stat_item_values[SI_AUDIOD_STATUS] = new;
 497                 stat_client_write_item(SI_AUDIOD_STATUS);
 498         } else
 499                 free(new);
 500
 501         old = stat_item_values[SI_DECODER_FLAGS];
 502         new = decoder_flags();
 503         if (!old || strcmp(old, new)) {
 504                 free(old);
 505                 stat_item_values[SI_DECODER_FLAGS] = new;
 506                 stat_client_write_item(SI_DECODER_FLAGS);
 507         } else
 508                 free(new);
 509 }
 510
 511 /**
 512  * Flush and send all status items.
 513  *
 514  * Send to  each connected client the full status item list
 515  * with empty values.
 516  */
 517 void clear_and_dump_items(void)
 518 {
 519         int i;
 520
 521         FOR_EACH_STATUS_ITEM(i) {
 522                 free(stat_item_values[i]);
 523                 stat_item_values[i] = NULL;
 524                 stat_client_write_item(i);
 525         }
 526 }