Hi Fred,

On 03/25/2013 12:16 PM, Frédéric Dalleau wrote:
> This code can register an handsfree audio agent and receive NewConnection and
> Release calls.
> ---
>   tools/handsfree-audio.c |  332 +++++++++++++++++++++++++++++++++++++++++++++++
>   1 file changed, 332 insertions(+)
>   create mode 100644 tools/handsfree-audio.c
>
> diff --git a/tools/handsfree-audio.c b/tools/handsfree-audio.c
> new file mode 100644
> index 0000000..88310aa
> --- /dev/null
> +++ b/tools/handsfree-audio.c
> @@ -0,0 +1,332 @@
> +/*
> + *
> + *  oFono - Open Source Telephony
> + *
> + *  Copyright (C) 2013  Intel Corporation. All rights reserved.
> + *
> + *  This program is free software; you can redistribute it and/or modify
> + *  it under the terms of the GNU General Public License version 2 as
> + *  published by the Free Software Foundation.
> + *
> + *  This program 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 General Public License
> + *  along with this program; if not, write to the Free Software
> + *  Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
> + *
> + */
> +
> +#ifdef HAVE_CONFIG_H
> +#include<config.h>
> +#endif
> +
> +#include<stdio.h>
> +#include<errno.h>
> +#include<fcntl.h>
> +#include<unistd.h>
> +#include<stdlib.h>
> +#include<string.h>
> +#include<signal.h>
> +
> +#include<gdbus.h>
> +#include<glib.h>
> +
> +#define OFONO_SERVICE			"org.ofono"
> +#define HFP_AUDIO_MANAGER_PATH		"/"
> +#define HFP_AUDIO_MANAGER_INTERFACE	OFONO_SERVICE ".HandsfreeAudioManager"
> +#define HFP_AUDIO_AGENT_PATH		"/hfpaudioagent"
> +#define HFP_AUDIO_AGENT_INTERFACE	OFONO_SERVICE ".HandsfreeAudioAgent"
> +
> +#define HFP_AUDIO_CVSD			1
> +#define HFP_AUDIO_MSBC			2
> +
> +#define DBG(fmt, arg...) do {\
> +		g_print("%s: " fmt "\n", __FUNCTION__, ## arg);\
> +	} while (0)
> +
> +/* DBus related */
> +static GMainLoop *main_loop = NULL;
> +static DBusConnection *conn;
> +static GSList *hcons = NULL;

This variable needs to be named differently.  Perhaps audio_connections, 
or active_list, or something else more descriptive.

> +
> +static gboolean option_nocvsd = FALSE;

I don't think it makes sense to have a nocvsd option.  That one is 
mandatory and we cannot register multiple agents.

> +static gboolean option_nomsbc = FALSE;
> +
> +struct hfp_audio_conn {
> +	unsigned char codec;
> +	int watch;
> +};
> +
> +static void hfp_audio_conn_free(struct hfp_audio_conn *hcon)
> +{
> +	DBG("Freeing audio connection %p", hcon);
> +
> +	hcons = g_slist_remove(hcons, hcon);
> +	g_source_remove(hcon->watch);
> +	g_free(hcon);
> +}
> +
> +static gboolean hfp_audio_cb(GIOChannel *io, GIOCondition cond, gpointer data)
> +{
> +	struct hfp_audio_conn *hcon = data;
> +	gsize read;
> +	gsize written;
> +	char buf[60];
> +
> +	if (cond&  (G_IO_HUP | G_IO_NVAL | G_IO_ERR))
> +		goto fail;
> +
> +	if (g_io_channel_read_chars(io, buf, sizeof(buf),&read, NULL) !=
> +			G_IO_STATUS_NORMAL)
> +		goto fail;
> +
> +	g_io_channel_write_chars(io, buf+written, read,&written, NULL);

Something is funky here with the written variable.  I do not see it 
being initialized.  Also, I don't really understand the logic, you're 
reading a max of 60 bytes into buf and writing the number of read into 
the io channel.  Why do you even need 'written'?

> +
> +	return TRUE;
> +
> +fail:
> +	DBG("Disconnected");
> +	hfp_audio_conn_free(hcon);
> +	return FALSE;
> +}
> +
> +static DBusMessage *agent_newconnection(DBusConnection *conn, DBusMessage *msg,
> +					void *data)
> +{
> +	const char *card;
> +	int fd;
> +	unsigned char codec;
> +	GIOChannel *io;
> +	struct hfp_audio_conn *hcon;
> +
> +	DBG("New connection");
> +
> +	if (dbus_message_get_args(msg, NULL, DBUS_TYPE_OBJECT_PATH,&card,
> +						DBUS_TYPE_UNIX_FD,&fd,
> +						DBUS_TYPE_BYTE,&codec,
> +						DBUS_TYPE_INVALID) == FALSE)
> +		return g_dbus_create_error(msg,
> +				HFP_AUDIO_AGENT_INTERFACE ".InvalidArguments",
> +				"Invalid arguments");
> +
> +	DBG("New connection: card=%s fd=%d codec=%d", card, fd, codec);
> +
> +	io = g_io_channel_unix_new(fd);
> +
> +	hcon = g_try_malloc0(sizeof(struct hfp_audio_conn));
> +	if (hcon == NULL)
> +		return NULL;

What do you do with io/fd in this case?  Please just use g_new0 here.

> +
> +	hcon->codec = codec;
> +	hcon->watch = g_io_add_watch(io, G_IO_IN, hfp_audio_cb, hcon);
> +	hcons = g_slist_prepend(hcons, hcon);
> +
> +	return dbus_message_new_method_return(msg);
> +}
> +
> +static DBusMessage *agent_release(DBusConnection *conn, DBusMessage *msg,
> +					void *data)
> +{
> +	DBG("HFP audio agent released");
> +	return dbus_message_new_method_return(msg);

You might as well clean up and exit here.

> +}
> +
> +static const GDBusMethodTable agent_methods[] = {
> +	{ GDBUS_METHOD("NewConnection", NULL, NULL, agent_newconnection) },
> +	{ GDBUS_METHOD("Release", NULL, NULL, agent_release) },
> +	{ },
> +};
> +
> +static void hfp_audio_agent_register_reply(DBusPendingCall *call, void *data)
> +{
> +	DBusMessage *reply = dbus_pending_call_steal_reply(call);
> +	DBusError err;
> +
> +	dbus_error_init(&err);
> +
> +	if (dbus_set_error_from_message(&err, reply) == TRUE) {
> +		DBG("Failed to register audio agent (%s: %s)", err.name,
> +								err.message);
> +		dbus_error_free(&err);
> +	} else {
> +		DBG("HFP audio agent registered");
> +	}
> +
> +	dbus_message_unref(reply);
> +}
> +
> +static void hfp_audio_agent_register(DBusConnection *conn)
> +{
> +	DBusMessage *msg;
> +	DBusPendingCall *call;
> +	const char *path = HFP_AUDIO_AGENT_PATH;
> +	unsigned char codecs[2];
> +	const unsigned char *pcodecs = codecs;
> +	int ncodecs = 0;
> +
> +	DBG("Registering audio agent");
> +
> +	msg = dbus_message_new_method_call(OFONO_SERVICE,
> +						HFP_AUDIO_MANAGER_PATH,
> +						HFP_AUDIO_MANAGER_INTERFACE,
> +						"Register");
> +	if (msg == NULL) {
> +		DBG("Not enough memory");
> +		return;
> +	}
> +
> +	if (option_nocvsd == FALSE)
> +		codecs[ncodecs++] = HFP_AUDIO_CVSD;
> +
> +	if (option_nomsbc == FALSE)
> +		codecs[ncodecs++] = HFP_AUDIO_MSBC;
> +
> +	dbus_message_append_args(msg, DBUS_TYPE_OBJECT_PATH,&path,
> +					DBUS_TYPE_ARRAY, DBUS_TYPE_BYTE,
> +					&pcodecs, ncodecs, DBUS_TYPE_INVALID);
> +
> +	if (!dbus_connection_send_with_reply(conn, msg,&call, -1)) {
> +		dbus_message_unref(msg);
> +		DBG("Unable to register agent");
> +		return;
> +	}
> +
> +	dbus_message_unref(msg);
> +
> +	if (call == NULL) {
> +		DBG("Unable to register agent");
> +		return;
> +	}
> +
> +	dbus_pending_call_set_notify(call, hfp_audio_agent_register_reply,
> +						NULL, NULL);
> +
> +	dbus_pending_call_unref(call);
> +}
> +
> +static void hfp_audio_agent_create(DBusConnection *conn)
> +{
> +	DBG("Creating audio agent");
> +
> +	if (!g_dbus_register_interface(conn, HFP_AUDIO_AGENT_PATH,
> +					HFP_AUDIO_AGENT_INTERFACE,
> +					agent_methods, NULL, NULL,
> +					NULL, NULL)) {
> +		DBG("Unable to create local agent");
> +		g_main_loop_quit(main_loop);
> +	}
> +}
> +
> +static void hfp_audio_agent_destroy(DBusConnection *conn)
> +{
> +	DBG("Destroying audio agent");
> +
> +	g_dbus_unregister_interface(conn, HFP_AUDIO_AGENT_PATH,
> +						HFP_AUDIO_AGENT_INTERFACE);
> +}
> +
> +static void ofono_connect(DBusConnection *conn, void *user_data)
> +{
> +	DBG("oFono appeared");
> +
> +	hfp_audio_agent_register(conn);
> +}
> +
> +static void ofono_disconnect(DBusConnection *conn, void *user_data)
> +{
> +	DBG("oFono disappeared");
> +}
> +
> +static void disconnect_callback(DBusConnection *conn, void *user_data)
> +{
> +	DBG("Disconnected from BUS");
> +
> +	g_main_loop_quit(main_loop);
> +}
> +
> +static void sig_term(int sig)
> +{
> +	DBG("Terminating");
> +
> +	g_main_loop_quit(main_loop);
> +}
> +
> +static GOptionEntry options[] = {
> +	{ "nocvsd", 'c', 0, G_OPTION_ARG_NONE,&option_nocvsd,
> +				"Disable CVSD support" },
> +	{ "nomsbc", 'm', 0, G_OPTION_ARG_NONE,&option_nomsbc,
> +				"Disable MSBC support" },
> +	{ NULL },
> +};
> +
> +int main(int argc, char **argv)
> +{
> +	GOptionContext *context;
> +	GError *error = NULL;
> +	DBusError err;
> +	guint watch;
> +	struct sigaction sa;
> +
> +	context = g_option_context_new(NULL);
> +	g_option_context_add_main_entries(context, options, NULL);
> +
> +	if (g_option_context_parse(context,&argc,&argv,&error) == FALSE) {
> +		if (error != NULL) {
> +			DBG("%s", error->message);
> +			g_error_free(error);
> +		} else
> +			DBG("An unknown error occurred");
> +		exit(1);
> +	}
> +
> +	g_option_context_free(context);
> +
> +	if (option_nocvsd == TRUE&&  option_nomsbc == TRUE) {
> +		DBG("At least one codec must be supported");
> +		exit(2);
> +	}
> +
> +	main_loop = g_main_loop_new(NULL, FALSE);
> +
> +	dbus_error_init(&err);
> +
> +	conn = g_dbus_setup_bus(DBUS_BUS_SYSTEM, NULL,&err);
> +	if (conn == NULL) {
> +		if (dbus_error_is_set(&err) == TRUE) {
> +			DBG("%s", err.message);
> +			dbus_error_free(&err);
> +		} else
> +			DBG("Can't register with system bus");
> +		exit(1);
> +	}
> +
> +	g_dbus_set_disconnect_function(conn, disconnect_callback, NULL, NULL);
> +
> +	memset(&sa, 0, sizeof(sa));
> +	sa.sa_handler = sig_term;
> +	sigaction(SIGINT,&sa, NULL);
> +	sigaction(SIGTERM,&sa, NULL);
> +
> +	hfp_audio_agent_create(conn);
> +
> +	watch = g_dbus_add_service_watch(conn, OFONO_SERVICE,
> +				ofono_connect, ofono_disconnect, NULL, NULL);
> +
> +	g_main_loop_run(main_loop);
> +
> +	g_dbus_remove_watch(conn, watch);
> +
> +	while (hcons != NULL)
> +		hfp_audio_conn_free(hcons->data);
> +
> +	hfp_audio_agent_destroy(conn);
> +
> +	dbus_connection_unref(conn);
> +
> +	g_main_loop_unref(main_loop);
> +
> +	return 0;
> +}

Regards,
-Denis