code.delx.au - pulseaudio/blob - src/modules/gconf/module-gconf.c

   1 /* $Id$ */
   2
   3 /***
   4   This file is part of PulseAudio.
   5
   6   PulseAudio is free software; you can redistribute it and/or modify
   7   it under the terms of the GNU Lesser General Public License as published
   8   by the Free Software Foundation; either version 2 of the License,
   9   or (at your option) any later version.
  10
  11   PulseAudio is distributed in the hope that it will be useful, but
  12   WITHOUT ANY WARRANTY; without even the implied warranty of
  13   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
  14   General Public License for more details.
  15
  16   You should have received a copy of the GNU Lesser General Public License
  17   along with PulseAudio; if not, write to the Free Software
  18   Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307
  19   USA.
  20 ***/
  21
  22 #ifdef HAVE_CONFIG_H
  23 #include <config.h>
  24 #endif
  25
  26 #include <assert.h>
  27 #include <string.h>
  28 #include <unistd.h>
  29 #include <stdlib.h>
  30 #include <errno.h>
  31 #include <signal.h>
  32 #include <sys/types.h>
  33 #include <sys/wait.h>
  34 #include <fcntl.h>
  35
  36 #ifdef HAVE_SYS_PRCTL_H
  37 #include <sys/prctl.h>
  38 #endif
  39 #ifdef HAVE_SYS_RESOURCE_H
  40 #include <sys/resource.h>
  41 #endif
  42
  43 #include <pulsecore/module.h>
  44 #include <pulsecore/core.h>
  45 #include <pulsecore/llist.h>
  46 #include <pulsecore/core-util.h>
  47 #include <pulsecore/log.h>
  48 #include <pulse/mainloop-api.h>
  49 #include <pulse/xmalloc.h>
  50 #include <pulsecore/core-error.h>
  51
  52 #include "module-gconf-symdef.h"
  53
  54 PA_MODULE_AUTHOR("Lennart Poettering")
  55 PA_MODULE_DESCRIPTION("GConf Adapter")
  56 PA_MODULE_VERSION(PACKAGE_VERSION)
  57 PA_MODULE_USAGE("")
  58
  59 #define MAX_MODULES 10
  60 #define BUF_MAX 2048
  61
  62 /* #undef PA_GCONF_HELPER */
  63 /* #define PA_GCONF_HELPER "/home/lennart/projects/pulseaudio/src/gconf-helper" */
  64
  65 struct module_item {
  66     char *name;
  67     char *args;
  68     uint32_t index;
  69 };
  70
  71 struct module_info {
  72     char *name;
  73
  74     struct module_item items[MAX_MODULES];
  75     unsigned n_items;
  76 };
  77
  78 struct userdata {
  79     pa_core *core;
  80     pa_module *module;
  81
  82     pa_hashmap *module_infos;
  83
  84     pid_t pid;
  85
  86     int fd;
  87     int fd_type;
  88     pa_io_event *io_event;
  89
  90     char buf[BUF_MAX];
  91     size_t buf_fill;
  92 };
  93
  94 static int fill_buf(struct userdata *u) {
  95     ssize_t r;
  96     assert(u);
  97
  98     if (u->buf_fill >= BUF_MAX) {
  99         pa_log(__FILE__": read buffer overflow");
 100         return -1;
 101     }
 102
 103     if ((r = pa_read(u->fd, u->buf + u->buf_fill, BUF_MAX - u->buf_fill, &u->fd_type)) <= 0)
 104         return -1;
 105
 106     u->buf_fill += r;
 107     return 0;
 108 }
 109
 110 static int read_byte(struct userdata *u) {
 111     int ret;
 112     assert(u);
 113
 114     if (u->buf_fill < 1)
 115         if (fill_buf(u) < 0)
 116             return -1;
 117
 118     ret = u->buf[0];
 119     assert(u->buf_fill > 0);
 120     u->buf_fill--;
 121     memmove(u->buf, u->buf+1, u->buf_fill);
 122     return ret;
 123 }
 124
 125 static char *read_string(struct userdata *u) {
 126     assert(u);
 127
 128     for (;;) {
 129         char *e;
 130
 131         if ((e = memchr(u->buf, 0, u->buf_fill))) {
 132             char *ret = pa_xstrdup(u->buf);
 133             u->buf_fill -= e - u->buf +1;
 134             memmove(u->buf, e+1, u->buf_fill);
 135             return ret;
 136         }
 137
 138         if (fill_buf(u) < 0)
 139             return NULL;
 140     }
 141 }
 142
 143 static void unload_one_module(struct userdata *u, struct module_info*m, unsigned i) {
 144     assert(u);
 145     assert(m);
 146     assert(i < m->n_items);
 147
 148     if (m->items[i].index == PA_INVALID_INDEX)
 149         return;
 150
 151     pa_log_debug(__FILE__": Unloading module #%i", m->items[i].index);
 152     pa_module_unload_by_index(u->core, m->items[i].index);
 153     m->items[i].index = PA_INVALID_INDEX;
 154     pa_xfree(m->items[i].name);
 155     pa_xfree(m->items[i].args);
 156     m->items[i].name = m->items[i].args = NULL;
 157 }
 158
 159 static void unload_all_modules(struct userdata *u, struct module_info*m) {
 160     unsigned i;
 161
 162     assert(u);
 163     assert(m);
 164
 165     for (i = 0; i < m->n_items; i++)
 166         unload_one_module(u, m, i);
 167
 168     m->n_items = 0;
 169 }
 170
 171 static void load_module(
 172         struct userdata *u,
 173         struct module_info *m,
 174         int i,
 175         const char *name,
 176         const char *args,
 177         int is_new) {
 178
 179     pa_module *mod;
 180
 181     assert(u);
 182     assert(m);
 183     assert(name);
 184     assert(args);
 185
 186     if (!is_new) {
 187         if (m->items[i].index != PA_INVALID_INDEX &&
 188             strcmp(m->items[i].name, name) == 0 &&
 189             strcmp(m->items[i].args, args) == 0)
 190             return;
 191
 192         unload_one_module(u, m, i);
 193     }
 194
 195     pa_log_debug(__FILE__": Loading module '%s' with args '%s' due to GConf configuration.", name, args);
 196
 197     m->items[i].name = pa_xstrdup(name);
 198     m->items[i].args = pa_xstrdup(args);
 199     m->items[i].index = PA_INVALID_INDEX;
 200
 201     if (!(mod = pa_module_load(u->core, name, args))) {
 202         pa_log(__FILE__": pa_module_load() failed");
 203         return;
 204     }
 205
 206     m->items[i].index = mod->index;
 207 }
 208
 209 static void module_info_free(void *p, void *userdata) {
 210     struct module_info *m = p;
 211     struct userdata *u = userdata;
 212
 213     assert(m);
 214     assert(u);
 215
 216     unload_all_modules(u, m);
 217     pa_xfree(m->name);
 218     pa_xfree(m);
 219 }
 220
 221 static int handle_event(struct userdata *u) {
 222     int opcode;
 223     int ret = 0;
 224
 225     do {
 226         if ((opcode = read_byte(u)) < 0)
 227             goto fail;
 228
 229         switch (opcode) {
 230             case '!':
 231                 /* The helper tool is now initialized */
 232                 ret = 1;
 233                 break;
 234
 235             case '+': {
 236                 char *name;
 237                 struct module_info *m;
 238                 unsigned i, j;
 239
 240                 if (!(name = read_string(u)))
 241                     goto fail;
 242
 243                 if (!(m = pa_hashmap_get(u->module_infos, name))) {
 244                     m = pa_xnew(struct module_info, 1);
 245                     m->name = name;
 246                     m->n_items = 0;
 247                     pa_hashmap_put(u->module_infos, m->name, m);
 248                 } else
 249                     pa_xfree(name);
 250
 251                 i = 0;
 252                 while (i < MAX_MODULES) {
 253                     char *module, *args;
 254
 255                     if (!(module = read_string(u))) {
 256                         if (i > m->n_items) m->n_items = i;
 257                         goto fail;
 258                     }
 259
 260                     if (!*module) {
 261                         pa_xfree(module);
 262                         break;
 263                     }
 264
 265                     if (!(args = read_string(u))) {
 266                         pa_xfree(module);
 267
 268                         if (i > m->n_items) m->n_items = i;
 269                         goto fail;
 270                     }
 271
 272                     load_module(u, m, i, module, args, i >= m->n_items);
 273
 274                     i++;
 275
 276                     pa_xfree(module);
 277                     pa_xfree(args);
 278                 }
 279
 280                 /* Unload all removed modules */
 281                 for (j = i; j < m->n_items; j++)
 282                     unload_one_module(u, m, j);
 283
 284                 m->n_items = i;
 285
 286                 break;
 287             }
 288
 289             case '-': {
 290                 char *name;
 291                 struct module_info *m;
 292
 293                 if (!(name = read_string(u)))
 294                     goto fail;
 295
 296                 if ((m = pa_hashmap_get(u->module_infos, name))) {
 297                     pa_hashmap_remove(u->module_infos, name);
 298                     module_info_free(m, u);
 299                 }
 300
 301                 pa_xfree(name);
 302
 303                 break;
 304             }
 305         }
 306     } while (u->buf_fill > 0 && ret == 0);
 307
 308     return ret;
 309
 310 fail:
 311     pa_log(__FILE__": Unable to read or parse data from client.");
 312     return -1;
 313 }
 314
 315 static void io_event_cb(
 316         pa_mainloop_api*a,
 317         pa_io_event* e,
 318         int fd,
 319         pa_io_event_flags_t events,
 320         void *userdata) {
 321
 322     struct userdata *u = userdata;
 323
 324     if (handle_event(u) < 0) {
 325
 326         if (u->io_event) {
 327             u->core->mainloop->io_free(u->io_event);
 328             u->io_event = NULL;
 329         }
 330
 331         pa_module_unload_request(u->module);
 332     }
 333 }
 334
 335 static int start_client(const char *n, pid_t *pid) {
 336     pid_t child;
 337     int pipe_fds[2] = { -1, -1 };
 338
 339     if (pipe(pipe_fds) < 0) {
 340         pa_log(__FILE__": pipe() failed: %s", pa_cstrerror(errno));
 341         goto fail;
 342     }
 343
 344     if ((child = fork()) == (pid_t) -1) {
 345         pa_log(__FILE__": fork() failed: %s", pa_cstrerror(errno));
 346         goto fail;
 347     } else if (child != 0) {
 348
 349         /* Parent */
 350         close(pipe_fds[1]);
 351
 352         if (pid)
 353             *pid = child;
 354
 355         return pipe_fds[0];
 356     } else {
 357         int max_fd, i;
 358
 359         /* child */
 360
 361         close(pipe_fds[0]);
 362         dup2(pipe_fds[1], 1);
 363
 364         if (pipe_fds[1] != 1)
 365             close(pipe_fds[1]);
 366
 367         close(0);
 368         open("/dev/null", O_RDONLY);
 369
 370         close(2);
 371         open("/dev/null", O_WRONLY);
 372
 373         max_fd = 1024;
 374
 375 #ifdef HAVE_SYS_RESOURCE_H
 376         {
 377             struct rlimit r;
 378             if (getrlimit(RLIMIT_NOFILE, &r) == 0)
 379                 max_fd = r.rlim_max;
 380         }
 381 #endif
 382
 383         for (i = 3; i < max_fd; i++)
 384             close(i);
 385
 386 #ifdef PR_SET_PDEATHSIG
 387         /* On Linux we can use PR_SET_PDEATHSIG to have the helper
 388         process killed when the daemon dies abnormally. On non-Linux
 389         machines the client will die as soon as it writes data to
 390         stdout again (SIGPIPE) */
 391
 392         prctl(PR_SET_PDEATHSIG, SIGTERM, 0, 0, 0);
 393 #endif
 394
 395 #ifdef SIGPIPE
 396         /* Make sure that SIGPIPE kills the child process */
 397         signal(SIGPIPE, SIG_DFL);
 398 #endif
 399
 400         execl(n, n, NULL);
 401         _exit(1);
 402     }
 403
 404 fail:
 405     if (pipe_fds[0] >= 0)
 406         close(pipe_fds[0]);
 407
 408     if (pipe_fds[1] >= 0)
 409         close(pipe_fds[1]);
 410
 411     return -1;
 412 }
 413
 414 int pa__init(pa_core *c, pa_module*m) {
 415     struct userdata *u;
 416     int r;
 417
 418     u = pa_xnew(struct userdata, 1);
 419     u->core = c;
 420     u->module = m;
 421     m->userdata = u;
 422     u->module_infos = pa_hashmap_new(pa_idxset_string_hash_func, pa_idxset_string_compare_func);
 423     u->pid = (pid_t) -1;
 424     u->fd = -1;
 425     u->fd_type = 0;
 426     u->io_event = NULL;
 427     u->buf_fill = 0;
 428
 429     if ((u->fd = start_client(PA_GCONF_HELPER, &u->pid)) < 0)
 430         goto fail;
 431
 432     u->io_event = c->mainloop->io_new(
 433             c->mainloop,
 434             u->fd,
 435             PA_IO_EVENT_INPUT,
 436             io_event_cb,
 437             u);
 438
 439     do {
 440         if ((r = handle_event(u)) < 0)
 441             goto fail;
 442
 443         /* Read until the client signalled us that it is ready with
 444          * initialization */
 445     } while (r != 1);
 446
 447     return 0;
 448
 449 fail:
 450     pa__done(c, m);
 451     return -1;
 452 }
 453
 454 void pa__done(pa_core *c, pa_module*m) {
 455     struct userdata *u;
 456
 457     assert(c);
 458     assert(m);
 459
 460     if (!(u = m->userdata))
 461         return;
 462
 463     if (u->io_event)
 464         c->mainloop->io_free(u->io_event);
 465
 466     if (u->fd >= 0)
 467         close(u->fd);
 468
 469     if (u->pid != (pid_t) -1) {
 470         kill(u->pid, SIGTERM);
 471         waitpid(u->pid, NULL, 0);
 472     }
 473
 474     if (u->module_infos)
 475         pa_hashmap_free(u->module_infos, module_info_free, u);
 476
 477     pa_xfree(u);
 478 }
 479