audiod_command.c

   1 /*
   2  * Copyright (C) 2005-2009 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 #include <dirent.h>
  12
  13 #include "para.h"
  14 #include "audiod.cmdline.h"
  15 #include "list.h"
  16 #include "sched.h"
  17 #include "ggo.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 "fd.h"
  26 #include "audiod_command_list.h"
  27
  28 extern char *stat_item_values[NUM_STAT_ITEMS];
  29
  30 /** Iterate over the array of all audiod commands. */
  31 #define FOR_EACH_COMMAND(c) for (c = 0; audiod_cmds[c].name; c++)
  32
  33 /** The maximal number of simultaneous connections. */
  34 #define MAX_STAT_CLIENTS 50
  35
  36 /** Flags used for the stat command of para_audiod. */
  37 enum stat_client_flags {
  38         /** Enable parser-friendly output. */
  39         SCF_PARSER_FRIENDLY = 1,
  40 };
  41
  42 /**
  43  * Describes a status client of para_audiod.
  44  *
  45  * There's one such structure per audiod client that sent the 'stat' command.
  46  *
  47  * A status client is identified by its file descriptor.  para_audiod
  48  * keeps a list of connected status clients.
  49  */
  50 struct stat_client {
  51         /** The stat client's file descriptor. */
  52         int fd;
  53         /** Bitmask of those status items the client is interested in. */
  54         uint64_t item_mask;
  55         /** See \ref stat_client flags. s*/
  56         unsigned flags;
  57         /** Its entry in the list of stat clients. */
  58         struct list_head node;
  59 };
  60
  61 static INITIALIZED_LIST_HEAD(client_list);
  62 static int num_clients;
  63
  64 /** The list of all status items used by para_{server,audiod,gui}. */
  65 const char *status_item_list[] = {STATUS_ITEM_ARRAY};
  66
  67 static void dump_stat_client_list(void)
  68 {
  69         struct stat_client *sc;
  70
  71         list_for_each_entry(sc, &client_list, node)
  72                 PARA_INFO_LOG("stat client on fd %d\n", sc->fd);
  73 }
  74 /**
  75  * Add a status client to the list.
  76  *
  77  * \param fd The file descriptor of the client.
  78  * \param mask Bitfield of status items for this client.
  79  * \param parser_friendly Enable parser-friendly output mode.
  80  *
  81  * Only those status items having the bit set in \a mask will be
  82  * sent to the client.
  83  *
  84  * \return Positive value on success, or -E_TOO_MANY_CLIENTS if
  85  * the number of connected clients exceeds #MAX_STAT_CLIENTS.
  86  */
  87 static int stat_client_add(int fd, uint64_t mask, int parser_friendly)
  88 {
  89         struct stat_client *new_client;
  90
  91         if (num_clients >= MAX_STAT_CLIENTS) {
  92                 PARA_ERROR_LOG("maximal number of stat clients (%d) exceeded\n",
  93                         MAX_STAT_CLIENTS);
  94                 return -E_TOO_MANY_CLIENTS;
  95         }
  96         PARA_INFO_LOG("adding client on fd %d\n", fd);
  97         new_client = para_calloc(sizeof(struct stat_client));
  98         new_client->fd = fd;
  99         new_client->item_mask = mask;
 100         if (parser_friendly)
 101                 new_client->flags = SCF_PARSER_FRIENDLY;
 102         para_list_add(&new_client->node, &client_list);
 103         dump_stat_client_list();
 104         num_clients++;
 105         return 1;
 106 }
 107 /**
 108  * Write a message to all connected status clients.
 109  *
 110  * \param item_num The number of the status item of \a msg.
 111  *
 112  * On write errors, remove the status client from the client list and close its
 113  * file descriptor.
 114  */
 115 void stat_client_write_item(int item_num)
 116 {
 117         struct stat_client *sc, *tmp;
 118         struct para_buffer pb = {.flags = 0};
 119         struct para_buffer pfpb = {.flags = PBF_SIZE_PREFIX};
 120         const uint64_t one = 1;
 121
 122         list_for_each_entry_safe(sc, tmp, &client_list, node) {
 123                 int fd = sc->fd, ret;
 124
 125                 if (!((one << item_num) & sc->item_mask))
 126                         continue;
 127                 if (write_ok(fd) > 0) {
 128                         struct para_buffer *b =
 129                                 (sc->flags & SCF_PARSER_FRIENDLY)? &pfpb : &pb;
 130                         char *msg = stat_item_values[item_num];
 131                         if (!b->buf)
 132                                 WRITE_STATUS_ITEM(b, item_num, "%s\n",
 133                                         msg? msg : "");
 134                         ret = write(fd, b->buf, b->offset);
 135                         if (ret == b->offset)
 136                                 continue;
 137                 }
 138                 /* write error or fd not ready for writing */
 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 //      if (num_clients)
 149 //              PARA_DEBUG_LOG("%d client(s)\n", num_clients);
 150 }
 151
 152 /**
 153  * Check if string is a known status item.
 154  *
 155  * \param item Buffer containing the text to check.
 156  *
 157  * \return If \a item is a valid status item, the number of that status item is
 158  * returned. Otherwise, this function returns \p -E_UNKNOWN_STAT_ITEM.
 159  */
 160 static int stat_item_valid(const char *item)
 161 {
 162         int i;
 163         if (!item || !*item) {
 164                 PARA_ERROR_LOG("%s\n", "no item");
 165                 return -E_UNKNOWN_STAT_ITEM;
 166         }
 167         FOR_EACH_STATUS_ITEM(i)
 168                 if (!strcmp(status_item_list[i], item))
 169                         return i;
 170         PARA_ERROR_LOG("invalid stat item: %s\n", item);
 171         return -E_UNKNOWN_STAT_ITEM;
 172 }
 173
 174 static int client_write(int fd, const char *buf)
 175 {
 176         size_t len;
 177
 178         if (!buf)
 179                 return 0;
 180         len = strlen(buf);
 181         return write(fd, buf, len) != len? -E_CLIENT_WRITE: 1;
 182 }
 183
 184 __malloc static char *audiod_status_string(void)
 185 {
 186         const char *status = (audiod_status == AUDIOD_ON)?
 187                 "on" : (audiod_status == AUDIOD_OFF)? "off": "sb";
 188         return para_strdup(status);
 189 }
 190
 191 static int get_play_time_slot_num(void)
 192 {
 193         int i, oldest = -1;
 194
 195         FOR_EACH_SLOT(i) {
 196                 struct slot_info *s = &slot[i];
 197                 if (!s->wng)
 198                         continue;
 199                 if (oldest >= 0 && tv_diff(&s->wstime, &slot[oldest].wstime,
 200                                 NULL) > 0)
 201                         continue;
 202                 oldest = i;
 203         }
 204         return oldest;
 205 }
 206
 207 __malloc static char *decoder_flags(void)
 208 {
 209         int i;
 210         char flags[MAX_STREAM_SLOTS + 1];
 211
 212         FOR_EACH_SLOT(i) {
 213                 struct slot_info *s = &slot[i];
 214                 char flag = '0';
 215                 if (s->receiver_node)
 216                         flag += 1;
 217                 if (s->fc)
 218                         flag += 2;
 219                 if (s->wng)
 220                         flag += 4;
 221                 flags[i] = flag;
 222         }
 223         flags[MAX_STREAM_SLOTS] = '\0';
 224         return para_strdup(flags);
 225 }
 226
 227 static int dump_commands(int fd)
 228 {
 229         char *buf = para_strdup(""), *tmp = NULL;
 230         int i;
 231         ssize_t ret;
 232
 233         FOR_EACH_COMMAND(i) {
 234                 tmp = make_message("%s%s\t%s\n", buf, audiod_cmds[i].name,
 235                         audiod_cmds[i].description);
 236                 free(buf);
 237                 buf = tmp;
 238         }
 239         ret = client_write(fd, buf);
 240         free(buf);
 241         return ret;
 242 }
 243
 244 /*
 245  * command handlers don't close their fd on errors (ret < 0) so that
 246  * its caller can send an error message. Otherwise (ret >= 0) it's up
 247  * to each individual command to close the fd if necessary.
 248  */
 249
 250 int com_help(int fd, int argc, char **argv)
 251 {
 252         int i, ret;
 253         char *buf;
 254         const char *dflt = "No such command. Available commands:\n";
 255
 256         if (argc < 2) {
 257                 ret = dump_commands(fd);
 258                 goto out;
 259         }
 260         FOR_EACH_COMMAND(i) {
 261                 if (strcmp(audiod_cmds[i].name, argv[1]))
 262                         continue;
 263                 buf = make_message(
 264                         "NAME\n\t%s -- %s\n"
 265                         "SYNOPSIS\n\tpara_audioc %s\n"
 266                         "DESCRIPTION\n%s\n",
 267                         argv[1],
 268                         audiod_cmds[i].description,
 269                         audiod_cmds[i].usage,
 270                         audiod_cmds[i].help
 271                 );
 272                 ret = client_write(fd, buf);
 273                 free(buf);
 274                 goto out;
 275         }
 276         ret = client_write(fd, dflt);
 277         if (ret > 0)
 278                 ret = dump_commands(fd);
 279 out:
 280         if (ret >= 0)
 281                 close(fd);
 282         return ret;
 283 }
 284
 285 int com_tasks(int fd, __a_unused int argc, __a_unused char **argv)
 286 {
 287         char *tl = get_task_list();
 288         int ret = 1;
 289         if (tl)
 290                 ret = client_write(fd, tl);
 291         free(tl);
 292         if (ret > 0)
 293                 close(fd);
 294         return ret;
 295 }
 296
 297 int com_kill(int fd, int argc, char **argv)
 298 {
 299         int i, ret = 1;
 300         if (argc < 2)
 301                 return -E_AUDIOD_SYNTAX;
 302         for (i = 1; i < argc; i++) {
 303                 ret = kill_task(argv[i]);
 304                 if (ret < 0)
 305                         break;
 306         }
 307         if (ret > 0)
 308                 close(fd);
 309         return ret;
 310 }
 311
 312 int com_stat(int fd, int argc, char **argv)
 313 {
 314         int i, ret, parser_friendly = 0;
 315         uint64_t mask = 0;
 316         const uint64_t one = 1;
 317         struct para_buffer b = {.flags = 0};
 318
 319         for (i = 1; i < argc; i++) {
 320                 const char *arg = argv[i];
 321                 if (arg[0] != '-')
 322                         break;
 323                 if (!strcmp(arg, "--")) {
 324                         i++;
 325                         break;
 326                 }
 327                 if (!strncmp(arg, "-p", 2)) {
 328                         parser_friendly = 1;
 329                         b.flags = PBF_SIZE_PREFIX;
 330                         continue;
 331                 }
 332         }
 333         if (i >= argc)
 334                 mask--; /* set all bits */
 335         for (; i < argc; i++) {
 336                 ret = stat_item_valid(argv[i]);
 337                 if (ret < 0)
 338                         return ret;
 339                 mask |= (one << ret);
 340         }
 341         PARA_INFO_LOG("mask: 0x%llx\n", (long long unsigned)mask);
 342         FOR_EACH_STATUS_ITEM(i) {
 343                 char *item = stat_item_values[i];
 344                 if (!((one << i) & mask))
 345                         continue;
 346                 WRITE_STATUS_ITEM(&b, i, "%s\n", item? item : "");
 347         }
 348         ret = client_write(fd, b.buf);
 349         if (ret >= 0)
 350                 ret = stat_client_add(fd, mask, parser_friendly);
 351         free(b.buf);
 352         return ret;
 353 }
 354
 355 int com_grab(int fd, int argc, char **argv)
 356 {
 357         return grab_client_new(fd, argc, argv);
 358 }
 359
 360 __noreturn int com_term(int fd, __a_unused int argc, __a_unused char **argv)
 361 {
 362         close(fd);
 363         clean_exit(EXIT_SUCCESS, "terminating on user request");
 364 }
 365
 366 int com_on(int fd, __a_unused int argc, __a_unused char **argv)
 367 {
 368         audiod_status = AUDIOD_ON;
 369         close(fd);
 370         return 1;
 371 }
 372
 373 int com_off(int fd, __a_unused int argc, __a_unused char **argv)
 374 {
 375         audiod_status = AUDIOD_OFF;
 376         close(fd);
 377         return 1;
 378 }
 379
 380 int com_sb(int fd, __a_unused int argc, __a_unused char **argv)
 381 {
 382         audiod_status = AUDIOD_STANDBY;
 383         close(fd);
 384         return 1;
 385 }
 386
 387 int com_cycle(int fd, int argc, char **argv)
 388 {
 389         switch (audiod_status) {
 390                 case  AUDIOD_ON:
 391                         return com_sb(fd, argc, argv);
 392                         break;
 393                 case  AUDIOD_OFF:
 394                         return com_on(fd, argc, argv);
 395                         break;
 396                 case  AUDIOD_STANDBY:
 397                         return com_off(fd, argc, argv);
 398                         break;
 399         }
 400         close(fd);
 401         return 1;
 402 }
 403
 404 static int check_perms(uid_t uid)
 405 {
 406         int i;
 407
 408         if (!conf.user_allow_given)
 409                 return 1;
 410         for (i = 0; i < conf.user_allow_given; i++)
 411                 if (uid == conf.user_allow_arg[i])
 412                         return 1;
 413         return -E_UCRED_PERM;
 414 }
 415
 416 /**
 417  * handle arriving connections on the local socket
 418  *
 419  * \param accept_fd the fd to call accept() on
 420  *
 421  * This is called whenever para_audiod's main task detects an incoming
 422  * connection by the readability of \a accept_fd. This function reads the
 423  * command sent by the peer, checks the connecting user's permissions by using
 424  * unix socket credentials (if supported by the OS) and calls the corresponding
 425  * command handler if permissions are OK.
 426  *
 427  * \return positive on success, negative on errors
 428  *
 429  * \sa para_accept(), recv_cred_buffer()
 430  * */
 431 int handle_connect(int accept_fd)
 432 {
 433         int i, argc, ret, clifd = -1;
 434         char buf[MAXLINE], **argv = NULL;
 435         struct sockaddr_un unix_addr;
 436         uid_t uid;
 437
 438         ret = para_accept(accept_fd, &unix_addr, sizeof(struct sockaddr_un));
 439         if (ret < 0)
 440                 goto out;
 441         clifd = ret;
 442         ret = recv_cred_buffer(clifd, buf, sizeof(buf) - 1);
 443         if (ret < 0)
 444                 goto out;
 445         uid = ret;
 446         PARA_INFO_LOG("connection from user %i, buf: %s\n",  ret, buf);
 447         ret = check_perms(uid);
 448         if (ret < 0)
 449                 goto out;
 450         ret = create_argv(buf, "\n", &argv);
 451         if (ret < 0)
 452                 goto out;
 453         argc = ret;
 454         //PARA_INFO_LOG("argv[0]: %s, argc = %d\n", argv[0], argc);
 455         FOR_EACH_COMMAND(i) {
 456                 if (strcmp(audiod_cmds[i].name, argv[0]))
 457                         continue;
 458                 ret = audiod_cmds[i].handler(clifd, argc, argv);
 459                 goto out;
 460         }
 461         ret = -E_INVALID_AUDIOD_CMD;
 462 out:
 463         free_argv(argv);
 464         if (clifd > 0 && ret < 0 && ret != -E_CLIENT_WRITE) {
 465                 char *tmp = make_message("%s\n", para_strerror(-ret));
 466                 client_write(clifd, tmp);
 467                 free(tmp);
 468                 close(clifd);
 469         }
 470         return ret;
 471 }
 472
 473 /**
 474  * Send the current audiod status to all connected stat clients.
 475  */
 476 void audiod_status_dump(void)
 477 {
 478         int slot_num = get_play_time_slot_num();
 479         char *old, *new;
 480
 481         old = stat_item_values[SI_PLAY_TIME];
 482         new = get_time_string(slot_num);
 483         if (new) {
 484                 if (!old || strcmp(old, new)) {
 485                         free(old);
 486                         stat_item_values[SI_PLAY_TIME] = new;
 487                         stat_client_write_item(SI_PLAY_TIME);
 488                 } else
 489                         free(new);
 490         }
 491
 492         new = uptime_str();
 493         old = stat_item_values[SI_AUDIOD_UPTIME];
 494         if (!old || strcmp(old, new)) {
 495                 free(old);
 496                 stat_item_values[SI_AUDIOD_UPTIME] = new;
 497                 stat_client_write_item(SI_AUDIOD_UPTIME);
 498         } else
 499                 free(new);
 500
 501         old = stat_item_values[SI_AUDIOD_STATUS];
 502         new = audiod_status_string();
 503         if (!old || strcmp(old, new)) {
 504                 free(old);
 505                 stat_item_values[SI_AUDIOD_STATUS] = new;
 506                 stat_client_write_item(SI_AUDIOD_STATUS);
 507         } else
 508                 free(new);
 509
 510         old = stat_item_values[SI_DECODER_FLAGS];
 511         new = decoder_flags();
 512         if (!old || strcmp(old, new)) {
 513                 free(old);
 514                 stat_item_values[SI_DECODER_FLAGS] = new;
 515                 stat_client_write_item(SI_DECODER_FLAGS);
 516         } else
 517                 free(new);
 518 }
 519
 520 /**
 521  * Flush and send all status items.
 522  *
 523  * Send to  each connected client the full status item list
 524  * with empty values.
 525  */
 526 void clear_and_dump_items(void)
 527 {
 528         int i;
 529
 530         FOR_EACH_STATUS_ITEM(i) {
 531                 free(stat_item_values[i]);
 532                 stat_item_values[i] = NULL;
 533                 stat_client_write_item(i);
 534         }
 535 }