Hi Howard,
On Thu, Jul 22, 2021 at 12:23 AM Howard Chung <howardchung@xxxxxxxxxx> wrote:
>
> From: Yun-Hao Chung <howardchung@xxxxxxxxxxxx>
>
> This adds an D-BUS client to listen for DeviceAdd and DeviceRemove. It
> is necessary for implementation of "AffectedByPolicy" property since it
> needs to register an interface for each device object and unregister it
> once the device gets removed.
>
> Reviewed-by: Miao-chen Chou <mcchou@xxxxxxxxxxxx>
> ---
> The following test steps were performed:
> 1. start discovery using UI
> 2. verify device_data were added by checking system log
> 3. stop discovery
> 4. verify device_data were removed after a few seconds by checking
> system log
>
> (no changes since v1)
>
> plugins/admin_policy.c | 154 +++++++++++++++++++++++++++++++++++++++--
> 1 file changed, 150 insertions(+), 4 deletions(-)
>
> diff --git a/plugins/admin_policy.c b/plugins/admin_policy.c
> index 270d42366cd6..73d695ef976b 100644
> --- a/plugins/admin_policy.c
> +++ b/plugins/admin_policy.c
> @@ -20,6 +20,7 @@
>
> #include "src/adapter.h"
> #include "src/dbus-common.h"
> +#include "src/device.h"
> #include "src/error.h"
> #include "src/log.h"
> #include "src/plugin.h"
> @@ -29,7 +30,12 @@
> #define ADMIN_POLICY_SET_INTERFACE "org.bluez.AdminPolicySet1"
> #define ADMIN_POLICY_STATUS_INTERFACE "org.bluez.AdminPolicyStatus1"
>
> +#define DBUS_BLUEZ_SERVICE "org.bluez"
> +#define BTD_DEVICE_INTERFACE "org.bluez.Device1"
> +
> static DBusConnection *dbus_conn;
> +static GDBusClient *dbus_client;
> +static struct queue *devices; /* List of struct device_data objects */
>
> /* |policy_data| has the same life cycle as btd_adapter */
> static struct btd_admin_policy {
> @@ -38,6 +44,11 @@ static struct btd_admin_policy {
> struct queue *service_allowlist;
> } *policy_data = NULL;
>
> +struct device_data {
> + struct btd_device *device;
> + char *path;
> +};
> +
> static struct btd_admin_policy *admin_policy_new(struct btd_adapter *adapter)
> {
> struct btd_admin_policy *admin_policy = NULL;
> @@ -203,8 +214,122 @@ static const GDBusPropertyTable admin_policy_adapter_properties[] = {
> { }
> };
>
> +static bool device_data_match(const void *a, const void *b)
> +{
> + const struct device_data *data = a;
> + const struct btd_device *dev = b;
> +
> + if (!data) {
> + error("Unexpected NULL device_data");
> + return false;
> + }
> +
> + return data->device == dev;
> +}
> +
> +static bool device_data_match_by_path(const void *a, const void *b)
> +{
> + const struct device_data *data = a;
> + const char *path = b;
> +
> + if (!data) {
> + error("Unexpected NULL device_data");
> + return false;
> + }
> +
> + return strcmp(data->path, b) == 0;
> +}
> +
> +static void free_device_data(void *data)
> +{
> + struct device_data *device_data = data;
> +
> + g_free(device_data->path);
> + g_free(device_data);
> +}
> +
> +static void remove_device_data(void *data)
> +{
> + struct device_data *device_data = data;
> +
> + DBG("device_data for %s removing", device_data->path);
> +
> + queue_remove(devices, device_data);
> + free_device_data(device_data);
> +}
> +
> +static void add_device_data(struct btd_device *device)
> +{
> + struct btd_adapter *adapter = device_get_adapter(device);
> + struct device_data *data;
> +
> + if (queue_find(devices, device_data_match, device))
> + return;
> +
> + data = g_new0(struct device_data, 1);
> + if (!data) {
> + btd_error(btd_adapter_get_index(adapter),
> + "Failed to allocate memory for device_data");
> + return;
> + }
> +
> + data->device = device;
> + data->path = g_strdup(device_get_path(device));
> + queue_push_tail(devices, data);
> +
> + DBG("device_data for %s added", data->path);
> +}
> +
> +static struct btd_device *find_device_by_proxy(GDBusProxy *proxy)
> +{
> + const char *path = g_dbus_proxy_get_path(proxy);
> + const char *iface = g_dbus_proxy_get_interface(proxy);
> + struct btd_device *device;
> +
> + if (strcmp(iface, BTD_DEVICE_INTERFACE) != 0)
> + return NULL;
> +
> + device = btd_adapter_find_device_by_path(policy_data->adapter, path);
> +
> + if (!device) {
> + btd_warn(adapter_get_path(policy_data->adapter),
> + "Device path %s is not found", path);
> + }
> +
> + return device;
> +}
> +
> +static void object_added_cb(GDBusProxy *proxy, void *user_data)
> +{
> + struct btd_device *device;
> +
> + device = find_device_by_proxy(proxy);
> +
> + if (!device)
> + return;
> +
> + add_device_data(device);
> +}
> +
> +static void object_removed_cb(GDBusProxy *proxy, void *user_data)
> +{
> + const char *path = g_dbus_proxy_get_path(proxy);
> + const char *iface = g_dbus_proxy_get_interface(proxy);
> + struct device_data *data;
> +
> + if (strcmp(iface, BTD_DEVICE_INTERFACE) != 0)
> + return;
> +
> + data = queue_find(devices, device_data_match_by_path, path);
> +
> + if (data)
> + remove_device_data(data);
> +}
> +
> static int admin_policy_adapter_probe(struct btd_adapter *adapter)
> {
> + const char *adapter_path;
> +
> if (policy_data) {
> btd_warn(policy_data->adapter_id,
> "Policy data already exists");
> @@ -216,33 +341,43 @@ static int admin_policy_adapter_probe(struct btd_adapter *adapter)
> if (!policy_data)
> return -ENOMEM;
>
> - if (!g_dbus_register_interface(dbus_conn, adapter_get_path(adapter),
> + adapter_path = adapter_get_path(adapter);
> +
> + if (!g_dbus_register_interface(dbus_conn, adapter_path,
> ADMIN_POLICY_SET_INTERFACE,
> admin_policy_adapter_methods, NULL,
> NULL, policy_data, admin_policy_free)) {
> btd_error(policy_data->adapter_id,
> "Admin Policy Set interface init failed on path %s",
> - adapter_get_path(adapter));
> + adapter_path);
> return -EINVAL;
> }
>
> btd_info(policy_data->adapter_id,
> "Admin Policy Set interface registered");
>
> - if (!g_dbus_register_interface(dbus_conn, adapter_get_path(adapter),
> + if (!g_dbus_register_interface(dbus_conn, adapter_path,
> ADMIN_POLICY_STATUS_INTERFACE,
> NULL, NULL,
> admin_policy_adapter_properties,
> policy_data, admin_policy_free)) {
> btd_error(policy_data->adapter_id,
> "Admin Policy Status interface init failed on path %s",
> - adapter_get_path(adapter));
> + adapter_path);
> return -EINVAL;
> }
>
> btd_info(policy_data->adapter_id,
> "Admin Policy Status interface registered");
>
> + dbus_client = g_dbus_client_new(dbus_conn, DBUS_BLUEZ_SERVICE,
> + adapter_path);
> +
> + g_dbus_client_set_proxy_handlers(dbus_client, object_added_cb,
> + object_removed_cb, NULL, NULL);
> +
> + g_dbus_client_set_ready_watch(dbus_client, NULL, NULL);
I hope it wasn't one of my comments that led you to do this, because
it is really a bad idea to listen to our own signals like that since
it comes from the same process it just adds a round trip to the D-Bus
daemon for no reason. Perhaps we could extend the btd_adapter_driver
to have device_added/device_remove callbacks so whenever a new device
is added or removed the driver will get notified.
> +
> return 0;
> }
>
> @@ -257,6 +392,7 @@ static int admin_policy_init(void)
> DBG("");
>
> dbus_conn = btd_get_dbus_connection();
> + devices = queue_new();
>
> return btd_register_adapter_driver(&admin_policy_driver);
> }
> @@ -266,9 +402,19 @@ static void admin_policy_exit(void)
> DBG("");
>
> btd_unregister_adapter_driver(&admin_policy_driver);
> + queue_destroy(devices, free_device_data);
>
> if (policy_data)
> admin_policy_free(policy_data);
> +
> + if (dbus_client) {
> + g_dbus_client_set_disconnect_watch(dbus_client, NULL, NULL);
> + g_dbus_client_set_proxy_handlers(dbus_client, NULL, NULL, NULL,
> + NULL);
> + g_dbus_client_set_ready_watch(dbus_client, NULL, NULL);
> + g_dbus_client_unref(dbus_client);
> + dbus_client = NULL;
> + }
> }
>
> BLUETOOTH_PLUGIN_DEFINE(admin_policy, VERSION,
> --
> 2.32.0.402.g57bb445576-goog
>
--
Luiz Augusto von Dentz
