src/pulsecore/module.c

   1 /***
   2   This file is part of PulseAudio.
   3
   4   Copyright 2004-2006 Lennart Poettering
   5   Copyright 2006 Pierre Ossman <ossman@cendio.se> for Cendio AB
   6
   7   PulseAudio is free software; you can redistribute it and/or modify
   8   it under the terms of the GNU Lesser General Public License as published
   9   by the Free Software Foundation; either version 2.1 of the License,
  10   or (at your option) any later version.
  11
  12   PulseAudio is distributed in the hope that it will be useful, but
  13   WITHOUT ANY WARRANTY; without even the implied warranty of
  14   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
  15   General Public License for more details.
  16
  17   You should have received a copy of the GNU Lesser General Public License
  18   along with PulseAudio; if not, write to the Free Software
  19   Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307
  20   USA.
  21 ***/
  22
  23 #ifdef HAVE_CONFIG_H
  24 #include <config.h>
  25 #endif
  26
  27 #include <limits.h>
  28 #include <stdio.h>
  29 #include <stdlib.h>
  30 #include <string.h>
  31 #include <errno.h>
  32 #include <ctype.h>
  33
  34 #include <pulse/timeval.h>
  35 #include <pulse/xmalloc.h>
  36 #include <pulse/proplist.h>
  37
  38 #include <pulsecore/core-subscribe.h>
  39 #include <pulsecore/log.h>
  40 #include <pulsecore/core-util.h>
  41 #include <pulsecore/macro.h>
  42 #include <pulsecore/ltdl-helper.h>
  43 #include <pulsecore/modinfo.h>
  44
  45 #include "module.h"
  46
  47 #define PA_SYMBOL_INIT "pa__init"
  48 #define PA_SYMBOL_DONE "pa__done"
  49 #define PA_SYMBOL_LOAD_ONCE "pa__load_once"
  50 #define PA_SYMBOL_GET_N_USED "pa__get_n_used"
  51 #define PA_SYMBOL_GET_DEPRECATE "pa__get_deprecated"
  52
  53 pa_module* pa_module_load(pa_core *c, const char *name, const char *argument) {
  54     pa_module *m = NULL;
  55     pa_bool_t (*load_once)(void);
  56     const char* (*get_deprecated)(void);
  57     pa_modinfo *mi;
  58
  59     pa_assert(c);
  60     pa_assert(name);
  61
  62     if (c->disallow_module_loading)
  63         goto fail;
  64
  65     m = pa_xnew(pa_module, 1);
  66     m->name = pa_xstrdup(name);
  67     m->argument = pa_xstrdup(argument);
  68     m->load_once = FALSE;
  69     m->proplist = pa_proplist_new();
  70
  71     if (!(m->dl = lt_dlopenext(name))) {
  72         pa_log("Failed to open module \"%s\": %s", name, lt_dlerror());
  73         goto fail;
  74     }
  75
  76     if ((load_once = (pa_bool_t (*)(void)) pa_load_sym(m->dl, name, PA_SYMBOL_LOAD_ONCE))) {
  77
  78         m->load_once = load_once();
  79
  80         if (m->load_once) {
  81             pa_module *i;
  82             uint32_t idx;
  83             /* OK, the module only wants to be loaded once, let's make sure it is */
  84
  85             for (i = pa_idxset_first(c->modules, &idx); i; i = pa_idxset_next(c->modules, &idx)) {
  86                 if (strcmp(name, i->name) == 0) {
  87                     pa_log("Module \"%s\" should be loaded once at most. Refusing to load.", name);
  88                     goto fail;
  89                 }
  90             }
  91         }
  92     }
  93
  94     if ((get_deprecated = (const char* (*) (void)) pa_load_sym(m->dl, name, PA_SYMBOL_GET_DEPRECATE))) {
  95         const char *t;
  96
  97         if ((t = get_deprecated()))
  98             pa_log_warn("%s is deprecated: %s", name, t);
  99     }
 100
 101     if (!(m->init = (int (*)(pa_module*_m)) pa_load_sym(m->dl, name, PA_SYMBOL_INIT))) {
 102         pa_log("Failed to load module \"%s\": symbol \""PA_SYMBOL_INIT"\" not found.", name);
 103         goto fail;
 104     }
 105
 106     m->done = (void (*)(pa_module*_m)) pa_load_sym(m->dl, name, PA_SYMBOL_DONE);
 107     m->get_n_used = (int (*)(pa_module*_m)) pa_load_sym(m->dl, name, PA_SYMBOL_GET_N_USED);
 108     m->userdata = NULL;
 109     m->core = c;
 110     m->unload_requested = FALSE;
 111
 112     if (m->init(m) < 0) {
 113         pa_log_error("Failed to load  module \"%s\" (argument: \"%s\"): initialization failed.", name, argument ? argument : "");
 114         goto fail;
 115     }
 116
 117     pa_assert_se(pa_idxset_put(c->modules, m, &m->index) >= 0);
 118     pa_assert(m->index != PA_IDXSET_INVALID);
 119
 120     pa_log_info("Loaded \"%s\" (index: #%u; argument: \"%s\").", m->name, m->index, m->argument ? m->argument : "");
 121
 122     pa_subscription_post(c, PA_SUBSCRIPTION_EVENT_MODULE|PA_SUBSCRIPTION_EVENT_NEW, m->index);
 123
 124     if ((mi = pa_modinfo_get_by_handle(m->dl, name))) {
 125
 126         if (mi->author && !pa_proplist_contains(m->proplist, PA_PROP_MODULE_AUTHOR))
 127             pa_proplist_sets(m->proplist, PA_PROP_MODULE_AUTHOR, mi->author);
 128
 129         if (mi->description && !pa_proplist_contains(m->proplist, PA_PROP_MODULE_DESCRIPTION))
 130             pa_proplist_sets(m->proplist, PA_PROP_MODULE_DESCRIPTION, mi->description);
 131
 132         if (mi->version && !pa_proplist_contains(m->proplist, PA_PROP_MODULE_VERSION))
 133             pa_proplist_sets(m->proplist, PA_PROP_MODULE_VERSION, mi->version);
 134
 135         pa_modinfo_free(mi);
 136     }
 137
 138     return m;
 139
 140 fail:
 141
 142     if (m) {
 143         if (m->proplist)
 144             pa_proplist_free(m->proplist);
 145
 146         pa_xfree(m->argument);
 147         pa_xfree(m->name);
 148
 149         if (m->dl)
 150             lt_dlclose(m->dl);
 151
 152         pa_xfree(m);
 153     }
 154
 155     return NULL;
 156 }
 157
 158 static void pa_module_free(pa_module *m) {
 159     pa_assert(m);
 160     pa_assert(m->core);
 161
 162     pa_log_info("Unloading \"%s\" (index: #%u).", m->name, m->index);
 163
 164     if (m->done)
 165         m->done(m);
 166
 167     if (m->proplist)
 168         pa_proplist_free(m->proplist);
 169
 170     lt_dlclose(m->dl);
 171
 172     pa_log_info("Unloaded \"%s\" (index: #%u).", m->name, m->index);
 173
 174     pa_subscription_post(m->core, PA_SUBSCRIPTION_EVENT_MODULE|PA_SUBSCRIPTION_EVENT_REMOVE, m->index);
 175
 176     pa_xfree(m->name);
 177     pa_xfree(m->argument);
 178     pa_xfree(m);
 179 }
 180
 181 void pa_module_unload(pa_core *c, pa_module *m, pa_bool_t force) {
 182     pa_assert(c);
 183     pa_assert(m);
 184
 185     if (m->core->disallow_module_loading && !force)
 186         return;
 187
 188     if (!(m = pa_idxset_remove_by_data(c->modules, m, NULL)))
 189         return;
 190
 191     pa_module_free(m);
 192 }
 193
 194 void pa_module_unload_by_index(pa_core *c, uint32_t idx, pa_bool_t force) {
 195     pa_module *m;
 196     pa_assert(c);
 197     pa_assert(idx != PA_IDXSET_INVALID);
 198
 199     if (c->disallow_module_loading && !force)
 200         return;
 201
 202     if (!(m = pa_idxset_remove_by_index(c->modules, idx)))
 203         return;
 204
 205     pa_module_free(m);
 206 }
 207
 208 void pa_module_unload_all(pa_core *c) {
 209     pa_module *m;
 210     pa_assert(c);
 211
 212     while ((m = pa_idxset_steal_first(c->modules, NULL)))
 213         pa_module_free(m);
 214
 215     if (c->module_defer_unload_event) {
 216         c->mainloop->defer_free(c->module_defer_unload_event);
 217         c->module_defer_unload_event = NULL;
 218     }
 219 }
 220
 221 static void defer_cb(pa_mainloop_api*api, pa_defer_event *e, void *userdata) {
 222     void *state = NULL;
 223     pa_core *c = PA_CORE(userdata);
 224     pa_module *m;
 225
 226     pa_core_assert_ref(c);
 227     api->defer_enable(e, 0);
 228
 229     while ((m = pa_idxset_iterate(c->modules, &state, NULL)))
 230         if (m->unload_requested)
 231             pa_module_unload(c, m, TRUE);
 232 }
 233
 234 void pa_module_unload_request(pa_module *m, pa_bool_t force) {
 235     pa_assert(m);
 236
 237     if (m->core->disallow_module_loading && !force)
 238         return;
 239
 240     m->unload_requested = TRUE;
 241
 242     if (!m->core->module_defer_unload_event)
 243         m->core->module_defer_unload_event = m->core->mainloop->defer_new(m->core->mainloop, defer_cb, m->core);
 244
 245     m->core->mainloop->defer_enable(m->core->module_defer_unload_event, 1);
 246 }
 247
 248 void pa_module_unload_request_by_index(pa_core *c, uint32_t idx, pa_bool_t force) {
 249     pa_module *m;
 250     pa_assert(c);
 251
 252     if (!(m = pa_idxset_get_by_index(c->modules, idx)))
 253         return;
 254
 255     pa_module_unload_request(m, force);
 256 }
 257
 258 int pa_module_get_n_used(pa_module*m) {
 259     pa_assert(m);
 260
 261     if (!m->get_n_used)
 262         return -1;
 263
 264     return m->get_n_used(m);
 265 }