reserve: wrap device reservation monitor reference implementation

This commit is contained in:
Lennart Poettering 2009-06-05 19:03:16 +02:00
parent 1748fd2a0d
commit 3af5f8cb55
5 changed files with 479 additions and 4 deletions

View file

@ -1358,7 +1358,7 @@ libalsa_util_la_CFLAGS += $(UDEV_CFLAGS)
endif
if HAVE_DBUS
libalsa_util_la_SOURCES += modules/reserve.h modules/reserve.c
libalsa_util_la_SOURCES += modules/reserve.h modules/reserve.c modules/reserve-monitor.h modules/reserve-monitor.c
libalsa_util_la_LIBADD += $(DBUS_LIBS)
libalsa_util_la_CFLAGS += $(DBUS_CFLAGS)
endif
@ -1670,7 +1670,7 @@ update-sbc:
done
update-reserve:
for i in reserve.c reserve.h ; do \
for i in reserve.c reserve.h reserve-monitor.c reserve-monitor.h ; do \
wget -O modules/$$i http://git.0pointer.de/\?p=reserve.git\;a=blob_plain\;f=$$i\;hb=master ; \
done

View file

@ -0,0 +1,259 @@
/***
Copyright 2009 Lennart Poettering
Permission is hereby granted, free of charge, to any person
obtaining a copy of this software and associated documentation files
(the "Software"), to deal in the Software without restriction,
including without limitation the rights to use, copy, modify, merge,
publish, distribute, sublicense, and/or sell copies of the Software,
and to permit persons to whom the Software is furnished to do so,
subject to the following conditions:
The above copyright notice and this permission notice shall be
included in all copies or substantial portions of the Software.
THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
SOFTWARE.
***/
#include <string.h>
#include <unistd.h>
#include <errno.h>
#include <stdlib.h>
#include <stdio.h>
#include <assert.h>
#include "reserve-monitor.h"
struct rm_monitor {
int ref;
char *device_name;
char *service_name;
DBusConnection *connection;
unsigned busy:1;
unsigned filtering:1;
unsigned matching:1;
rm_change_cb_t change_cb;
void *userdata;
};
#define SERVICE_PREFIX "org.freedesktop.ReserveDevice1."
static DBusHandlerResult filter_handler(
DBusConnection *c,
DBusMessage *s,
void *userdata) {
DBusMessage *reply;
rm_monitor *m;
DBusError error;
dbus_error_init(&error);
m = userdata;
assert(m->ref >= 1);
if (dbus_message_is_signal(s, "org.freedesktop.DBus", "NameOwnerChanged")) {
const char *name, *old, *new;
if (!dbus_message_get_args(
s,
&error,
DBUS_TYPE_STRING, &name,
DBUS_TYPE_STRING, &old,
DBUS_TYPE_STRING, &new,
DBUS_TYPE_INVALID))
goto invalid;
if (strcmp(name, m->service_name) == 0) {
m->busy = !!(new && *new);
if (m->change_cb) {
m->ref++;
m->change_cb(m);
rm_release(m);
}
}
}
return DBUS_HANDLER_RESULT_NOT_YET_HANDLED;
invalid:
if (!(reply = dbus_message_new_error(
s,
DBUS_ERROR_INVALID_ARGS,
"Invalid arguments")))
goto oom;
if (!dbus_connection_send(c, reply, NULL))
goto oom;
dbus_message_unref(reply);
dbus_error_free(&error);
return DBUS_HANDLER_RESULT_HANDLED;
oom:
if (reply)
dbus_message_unref(reply);
dbus_error_free(&error);
return DBUS_HANDLER_RESULT_NEED_MEMORY;
}
int rm_watch(
rm_monitor **_m,
DBusConnection *connection,
const char*device_name,
rm_change_cb_t change_cb,
DBusError *error) {
rm_monitor *m = NULL;
int r;
DBusError _error;
if (!error)
error = &_error;
dbus_error_init(error);
if (!_m)
return -EINVAL;
if (!connection)
return -EINVAL;
if (!device_name)
return -EINVAL;
if (!(m = calloc(sizeof(rm_monitor), 1)))
return -ENOMEM;
m->ref = 1;
if (!(m->device_name = strdup(device_name))) {
r = -ENOMEM;
goto fail;
}
m->connection = dbus_connection_ref(connection);
m->change_cb = change_cb;
if (!(m->service_name = malloc(sizeof(SERVICE_PREFIX) + strlen(device_name)))) {
r = -ENOMEM;
goto fail;
}
sprintf(m->service_name, SERVICE_PREFIX "%s", m->device_name);
if (!(dbus_connection_add_filter(m->connection, filter_handler, m, NULL))) {
r = -ENOMEM;
goto fail;
}
m->filtering = 1;
dbus_bus_add_match(m->connection,
"type='signal',"
"sender='" DBUS_SERVICE_DBUS "',"
"interface='" DBUS_INTERFACE_DBUS "',"
"member='NameOwnerChanged'", error);
if (dbus_error_is_set(error)) {
r = -EIO;
goto fail;
}
m->matching = 1;
m->busy = dbus_bus_name_has_owner(m->connection, m->service_name, error);
if (dbus_error_is_set(error)) {
r = -EIO;
goto fail;
}
*_m = m;
return 0;
fail:
if (&_error == error)
dbus_error_free(&_error);
if (m)
rm_release(m);
return r;
}
void rm_release(rm_monitor *m) {
if (!m)
return;
assert(m->ref > 0);
if (--m->ref > 0)
return;
if (m->matching)
dbus_bus_remove_match(
m->connection,
"type='signal',"
"sender='" DBUS_SERVICE_DBUS "',"
"interface='" DBUS_INTERFACE_DBUS "',"
"member='NameOwnerChanged'", NULL);
if (m->filtering)
dbus_connection_remove_filter(
m->connection,
filter_handler,
m);
free(m->device_name);
free(m->service_name);
if (m->connection)
dbus_connection_unref(m->connection);
free(m);
}
int rm_busy(rm_monitor *m) {
if (!m)
return -EINVAL;
assert(m->ref > 0);
return m->busy;
}
void rm_set_userdata(rm_monitor *m, void *userdata) {
if (!m)
return;
assert(m->ref > 0);
m->userdata = userdata;
}
void* rm_get_userdata(rm_monitor *m) {
if (!m)
return NULL;
assert(m->ref > 0);
return m->userdata;
}

View file

@ -0,0 +1,62 @@
#ifndef fooreservemonitorhfoo
#define fooreservemonitorhfoo
/***
Copyright 2009 Lennart Poettering
Permission is hereby granted, free of charge, to any person
obtaining a copy of this software and associated documentation files
(the "Software"), to deal in the Software without restriction,
including without limitation the rights to use, copy, modify, merge,
publish, distribute, sublicense, and/or sell copies of the Software,
and to permit persons to whom the Software is furnished to do so,
subject to the following conditions:
The above copyright notice and this permission notice shall be
included in all copies or substantial portions of the Software.
THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
SOFTWARE.
***/
#include <dbus/dbus.h>
#include <inttypes.h>
typedef struct rm_monitor rm_monitor;
/* Prototype for a function that is called whenever the reservation
* device of a device changes. Use rm_monitor_busy() to find out the
* new state.*/
typedef void (*rm_change_cb_t)(rm_monitor *m);
/* Creates a monitor for watching the lock status of a device. Returns
* 0 on success, a negative errno style return value on error. The
* DBus error might be set as well if the error was caused D-Bus. */
int rm_watch(
rm_monitor **m, /* On success a pointer to the newly allocated rm_device object will be filled in here */
DBusConnection *connection, /* Session bus (when D-Bus learns about user busses we should switchg to user busses) */
const char *device_name, /* The device to monitor, e.g. "Audio0" */
rm_change_cb_t change_cb, /* Will be called whenever the lock status changes. May be NULL */
DBusError *error); /* If we fail due to a D-Bus related issue the error will be filled in here. May be NULL. */
/* Free a rm_monitor object */
void rm_release(rm_monitor *m);
/* Checks whether the device is currently reserved, and returns 1
* then, 0 if not, negative errno style error code value on error. */
int rm_busy(rm_monitor *m);
/* Attach a userdata pointer to an rm_monitor */
void rm_set_userdata(rm_monitor *m, void *userdata);
/* Query the userdata pointer from an rm_monitor. Returns NULL if no
* userdata was set. */
void* rm_get_userdata(rm_monitor *m);
#endif

View file

@ -35,6 +35,7 @@
#ifdef HAVE_DBUS
#include <pulsecore/dbus-shared.h>
#include "reserve.h"
#include "reserve-monitor.h"
#endif
#include "reserve-wrap.h"
@ -50,6 +51,17 @@ struct pa_reserve_wrapper {
#endif
};
struct pa_reserve_monitor_wrapper {
PA_REFCNT_DECLARE;
pa_core *core;
pa_hook hook;
char *shared_name;
#ifdef HAVE_DBUS
pa_dbus_connection *connection;
struct rm_monitor *monitor;
#endif
};
static void reserve_wrapper_free(pa_reserve_wrapper *r) {
pa_assert(r);
@ -83,7 +95,7 @@ static int request_cb(rd_device *d, int forced) {
PA_REFCNT_INC(r);
k = pa_hook_fire(&r->hook, PA_INT_TO_PTR(forced));
pa_log_debug("Device unlock has been requested and %s.", k < 0 ? "failed" : "succeeded");
pa_log_debug("Device unlock of %s has been requested and %s.", r->shared_name, k < 0 ? "failed" : "succeeded");
pa_reserve_wrapper_unref(r);
@ -191,3 +203,138 @@ void pa_reserve_wrapper_set_application_device_name(pa_reserve_wrapper *r, const
rd_set_application_device_name(r->device, name);
#endif
}
static void reserve_monitor_wrapper_free(pa_reserve_monitor_wrapper *w) {
pa_assert(w);
#ifdef HAVE_DBUS
if (w->monitor)
rm_release(w->monitor);
if (w->connection)
pa_dbus_connection_unref(w->connection);
#endif
pa_hook_done(&w->hook);
if (w->shared_name) {
pa_assert_se(pa_shared_remove(w->core, w->shared_name) >= 0);
pa_xfree(w->shared_name);
}
pa_xfree(w);
}
#ifdef HAVE_DBUS
static void change_cb(rm_monitor *m) {
pa_reserve_monitor_wrapper *w;
int k;
pa_assert(m);
pa_assert_se(w = rm_get_userdata(m));
pa_assert(PA_REFCNT_VALUE(w) >= 1);
PA_REFCNT_INC(w);
if ((k = rm_busy(w->monitor)) < 0)
return;
pa_hook_fire(&w->hook, PA_INT_TO_PTR(!!k));
pa_log_debug("Device lock status of %s changed: %s", w->shared_name, k ? "busy" : "not busy");
pa_reserve_monitor_wrapper_unref(w);
}
#endif
pa_reserve_monitor_wrapper* pa_reserve_monitor_wrapper_get(pa_core *c, const char *device_name) {
pa_reserve_monitor_wrapper *w;
int k;
char *t;
#ifdef HAVE_DBUS
DBusError error;
dbus_error_init(&error);
#endif
pa_assert(c);
pa_assert(device_name);
t = pa_sprintf_malloc("reserve-monitor-wrapper@%s", device_name);
if ((w = pa_shared_get(c, t))) {
pa_xfree(t);
pa_assert(PA_REFCNT_VALUE(w) >= 1);
PA_REFCNT_INC(w);
return w;
}
w = pa_xnew0(pa_reserve_monitor_wrapper, 1);
PA_REFCNT_INIT(w);
w->core = c;
pa_hook_init(&w->hook, w);
w->shared_name = t;
pa_assert_se(pa_shared_set(c, w->shared_name, w) >= 0);
#ifdef HAVE_DBUS
if (!(w->connection = pa_dbus_bus_get(c, DBUS_BUS_SESSION, &error)) || dbus_error_is_set(&error)) {
pa_log_warn("Unable to contact D-Bus session bus: %s: %s", error.name, error.message);
/* We don't treat this as error here because we want allow PA
* to run even when no session bus is available. */
return w;
}
if ((k = rm_watch(
&w->monitor,
pa_dbus_connection_get(w->connection),
device_name,
change_cb,
NULL)) < 0) {
pa_log_warn("Failed to create watch on device '%s': %s", device_name, pa_cstrerror(-k));
goto fail;
}
pa_log_debug("Successfully create reservation lock monitor for device '%s'", device_name);
rm_set_userdata(w->monitor, w);
return w;
fail:
dbus_error_free(&error);
reserve_monitor_wrapper_free(w);
return NULL;
#else
return w;
#endif
}
void pa_reserve_monitor_wrapper_unref(pa_reserve_monitor_wrapper *w) {
pa_assert(w);
pa_assert(PA_REFCNT_VALUE(w) >= 1);
if (PA_REFCNT_DEC(w) > 0)
return;
reserve_monitor_wrapper_free(w);
}
pa_hook* pa_reserve_monitor_wrapper_hook(pa_reserve_monitor_wrapper *w) {
pa_assert(w);
pa_assert(PA_REFCNT_VALUE(w) >= 1);
return &w->hook;
}
pa_bool_t pa_reserve_monitor_wrapper_busy(pa_reserve_monitor_wrapper *w) {
pa_assert(w);
pa_assert(PA_REFCNT_VALUE(w) >= 1);
return rm_busy(w->monitor) > 0;
}

View file

@ -28,11 +28,18 @@
typedef struct pa_reserve_wrapper pa_reserve_wrapper;
pa_reserve_wrapper* pa_reserve_wrapper_get(pa_core *c, const char *device_name);
void pa_reserve_wrapper_unref(pa_reserve_wrapper *r);
pa_hook* pa_reserve_wrapper_hook(pa_reserve_wrapper *r);
void pa_reserve_wrapper_set_application_device_name(pa_reserve_wrapper *r, const char *name);
typedef struct pa_reserve_monitor_wrapper pa_reserve_monitor_wrapper;
pa_reserve_monitor_wrapper* pa_reserve_monitor_wrapper_get(pa_core *c, const char *device_name);
void pa_reserve_monitor_wrapper_unref(pa_reserve_monitor_wrapper *m);
pa_hook* pa_reserve_monitor_wrapper_hook(pa_reserve_monitor_wrapper *m);
pa_bool_t pa_reserve_monitor_wrapper_busy(pa_reserve_monitor_wrapper *m);
#endif