bluetooth: module-bluetooth-policy initial commit

This is a basic module for enabling loopback as soon as a new bluetooth A2DP
source is created. The module is given a source and a media role using command
line. This allows module-intended-roles or module-device-manager to choose a
target sink for the stream.

src/Makefile.am

@@ -1241,6 +1241,7 @@ modlibexec_LTLIBRARIES += \
 		module-bluetooth-discover.la \
 		libbluetooth-ipc.la \
 		libbluetooth-sbc.la \
+		module-bluetooth-policy.la \
 		module-bluetooth-device.la
 
 pulselibexec_PROGRAMS += \
@@ -1332,6 +1333,7 @@ SYMDEF_FILES = \
 		module-systemd-login-symdef.h \
 		module-bluetooth-proximity-symdef.h \
 		module-bluetooth-discover-symdef.h \
+		module-bluetooth-policy-symdef.h \
 		module-bluetooth-device-symdef.h \
 		module-raop-sink-symdef.h \
 		module-raop-discover-symdef.h \
@@ -1948,6 +1950,11 @@ module_bluetooth_device_la_LDFLAGS = $(MODULE_LDFLAGS)
 module_bluetooth_device_la_LIBADD = $(MODULE_LIBADD) $(DBUS_LIBS) libbluetooth-util.la libbluetooth-ipc.la libbluetooth-sbc.la
 module_bluetooth_device_la_CFLAGS = $(AM_CFLAGS) $(DBUS_CFLAGS) -I$(top_srcdir)/src/modules/bluetooth/sbc
 
+module_bluetooth_policy_la_SOURCES = modules/bluetooth/module-bluetooth-policy.c
+module_bluetooth_policy_la_LDFLAGS = $(MODULE_LDFLAGS)
+module_bluetooth_policy_la_LIBADD = $(MODULE_LIBADD)
+module_bluetooth_policy_la_CFLAGS = $(AM_CFLAGS) $(DBUS_CFLAGS)
+
 # Apple Airtunes/RAOP
 module_raop_sink_la_SOURCES = modules/raop/module-raop-sink.c
 module_raop_sink_la_LDFLAGS = $(MODULE_LDFLAGS)

src/modules/bluetooth/module-bluetooth-policy.c

@@ -0,0 +1,107 @@
+/***
+  This file is part of PulseAudio.
+
+  Copyright 2006 Lennart Poettering
+  Copyright 2009 Canonical Ltd
+  Copyright (C) 2012 Intel Corporation
+
+  PulseAudio is free software; you can redistribute it and/or modify
+  it under the terms of the GNU Lesser General Public License as published
+  by the Free Software Foundation; either version 2.1 of the License,
+  or (at your option) any later version.
+
+  PulseAudio is distributed in the hope that it will be useful, but
+  WITHOUT ANY WARRANTY; without even the implied warranty of
+  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+  General Public License for more details.
+
+  You should have received a copy of the GNU Lesser General Public License
+  along with PulseAudio; if not, write to the Free Software
+  Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307
+  USA.
+***/
+
+#ifdef HAVE_CONFIG_H
+#include <config.h>
+#endif
+
+#include <pulse/xmalloc.h>
+
+#include <pulsecore/core.h>
+#include <pulsecore/source-output.h>
+#include <pulsecore/source.h>
+#include <pulsecore/core-util.h>
+
+#include "module-bluetooth-policy-symdef.h"
+
+PA_MODULE_AUTHOR("Frédéric Dalleau");
+PA_MODULE_DESCRIPTION("When an A2DP source is added, load module-loopback");
+PA_MODULE_VERSION(PACKAGE_VERSION);
+PA_MODULE_LOAD_ONCE(TRUE);
+
+struct userdata {
+     pa_hook_slot *source_put_slot;
+};
+
+/* When a source is created, loopback it to default sink */
+static pa_hook_result_t source_put_hook_callback(pa_core *c, pa_source *source, void* userdata) {
+    const char *s;
+    const char *role;
+    char *args;
+
+    pa_assert(c);
+    pa_assert(source);
+
+    /* Only consider bluetooth sinks and sources */
+    s = pa_proplist_gets(source->proplist, PA_PROP_DEVICE_BUS);
+    if (!s)
+        return PA_HOOK_OK;
+
+    if (!pa_streq(s, "bluetooth"))
+        return PA_HOOK_OK;
+
+    /* Restrict to A2DP profile (sink role) */
+    s = pa_proplist_gets(source->proplist, "bluetooth.protocol");
+    if (!s)
+        return PA_HOOK_OK;
+
+    if pa_streq(s, "a2dp_source")
+        role = "music";
+    else {
+        pa_log_debug("Profile %s cannot be selected for loopback", s);
+        return PA_HOOK_OK;
+    }
+
+    /* Load module-loopback */
+    args = pa_sprintf_malloc("source=\"%s\" source_dont_move=\"true\" sink_input_properties=\"media.role=%s\"", source->name, role);
+    (void) pa_module_load(c, "module-loopback", args);
+    pa_xfree(args);
+
+    return PA_HOOK_OK;
+}
+
+int pa__init(pa_module*m) {
+    struct userdata *u;
+
+    pa_assert(m);
+
+    m->userdata = u = pa_xnew(struct userdata, 1);
+
+    u->source_put_slot = pa_hook_connect(&m->core->hooks[PA_CORE_HOOK_SOURCE_PUT], PA_HOOK_NORMAL, (pa_hook_cb_t) source_put_hook_callback, u);
+
+    return 0;
+}
+
+void pa__done(pa_module*m) {
+    struct userdata *u;
+
+    pa_assert(m);
+
+    if (!(u = m->userdata))
+        return;
+
+    if (u->source_put_slot)
+        pa_hook_slot_free(u->source_put_slot);
+
+    pa_xfree(u);
+}