（一百零九）Android O wpa_supplicant初始化学习（三）—— hidl

版权声明：本文为博主原创文章，未经授权禁止转载，O(∩_∩)O谢谢 https://blog.csdn.net/sinat_20059415/article/details/84726364

前言：之前在（一百零三）Android O wpa_supplicant初始化学习（二）梳理到了wpa_supplicant_init方法，但是里面代码太多了，也不知道哪里是重点，这次凑巧梳理了其中一条关于hidl的初始化。

1.流程梳理

1.1 wpa_supplicant_init

wpa_supplicant.c

/**
 * wpa_supplicant_init - Initialize %wpa_supplicant
 * @params: Parameters for %wpa_supplicant
 * Returns: Pointer to global %wpa_supplicant data, or %NULL on failure
 *
 * This function is used to initialize %wpa_supplicant. After successful
 * initialization, the returned data pointer can be used to add and remove
 * network interfaces, and eventually, to deinitialize %wpa_supplicant.
 */
struct wpa_global * wpa_supplicant_init(struct wpa_params *params)
{
	struct wpa_global *global;
	int ret, i;

	if (params == NULL)
		return NULL;

#ifdef CONFIG_DRIVER_NDIS
	{
		void driver_ndis_init_ops(void);
		driver_ndis_init_ops();
	}
#endif /* CONFIG_DRIVER_NDIS */

#ifndef CONFIG_NO_WPA_MSG
	wpa_msg_register_ifname_cb(wpa_supplicant_msg_ifname_cb);
#endif /* CONFIG_NO_WPA_MSG */

	if (params->wpa_debug_file_path)
		wpa_debug_open_file(params->wpa_debug_file_path);
	else
		wpa_debug_setup_stdout();
	if (params->wpa_debug_syslog)
		wpa_debug_open_syslog();
	if (params->wpa_debug_tracing) {
		ret = wpa_debug_open_linux_tracing();
		if (ret) {
			wpa_printf(MSG_ERROR,
				   "Failed to enable trace logging");
			return NULL;
		}
	}

	ret = eap_register_methods();
	if (ret) {
		wpa_printf(MSG_ERROR, "Failed to register EAP methods");
		if (ret == -2)
			wpa_printf(MSG_ERROR, "Two or more EAP methods used "
				   "the same EAP type.");
		return NULL;
	}

	global = os_zalloc(sizeof(*global));
	if (global == NULL)
		return NULL;
	dl_list_init(&global->p2p_srv_bonjour);
	dl_list_init(&global->p2p_srv_upnp);
	global->params.daemonize = params->daemonize;
	global->params.wait_for_monitor = params->wait_for_monitor;
	global->params.dbus_ctrl_interface = params->dbus_ctrl_interface;
	if (params->pid_file)
		global->params.pid_file = os_strdup(params->pid_file);
	if (params->ctrl_interface)
		global->params.ctrl_interface =
			os_strdup(params->ctrl_interface);
	if (params->ctrl_interface_group)
		global->params.ctrl_interface_group =
			os_strdup(params->ctrl_interface_group);
	if (params->override_driver)
		global->params.override_driver =
			os_strdup(params->override_driver);
	if (params->override_ctrl_interface)
		global->params.override_ctrl_interface =
			os_strdup(params->override_ctrl_interface);
#ifdef CONFIG_MATCH_IFACE
	global->params.match_iface_count = params->match_iface_count;
	if (params->match_iface_count) {
		global->params.match_ifaces =
			os_calloc(params->match_iface_count,
				  sizeof(struct wpa_interface));
		os_memcpy(global->params.match_ifaces,
			  params->match_ifaces,
			  params->match_iface_count *
			  sizeof(struct wpa_interface));
	}
#endif /* CONFIG_MATCH_IFACE */
#ifdef CONFIG_P2P
	if (params->conf_p2p_dev)
		global->params.conf_p2p_dev =
			os_strdup(params->conf_p2p_dev);
#endif /* CONFIG_P2P */
	wpa_debug_level = global->params.wpa_debug_level =
		params->wpa_debug_level;
	wpa_debug_show_keys = global->params.wpa_debug_show_keys =
		params->wpa_debug_show_keys;
	wpa_debug_timestamp = global->params.wpa_debug_timestamp =
		params->wpa_debug_timestamp;

	wpa_printf(MSG_DEBUG, "wpa_supplicant v" VERSION_STR);

	if (eloop_init()) {
		wpa_printf(MSG_ERROR, "Failed to initialize event loop");
		wpa_supplicant_deinit(global);
		return NULL;
	}

	random_init(params->entropy_file);

	global->ctrl_iface = wpa_supplicant_global_ctrl_iface_init(global);
	if (global->ctrl_iface == NULL) {
		wpa_supplicant_deinit(global);
		return NULL;
	}

	if (wpas_notify_supplicant_initialized(global)) {
		wpa_supplicant_deinit(global);
		return NULL;
	}

	for (i = 0; wpa_drivers[i]; i++)
		global->drv_count++;
	if (global->drv_count == 0) {
		wpa_printf(MSG_ERROR, "No drivers enabled");
		wpa_supplicant_deinit(global);
		return NULL;
	}
	global->drv_priv = os_calloc(global->drv_count, sizeof(void *));
	if (global->drv_priv == NULL) {
		wpa_supplicant_deinit(global);
		return NULL;
	}

#ifdef CONFIG_WIFI_DISPLAY
	if (wifi_display_init(global) < 0) {
		wpa_printf(MSG_ERROR, "Failed to initialize Wi-Fi Display");
		wpa_supplicant_deinit(global);
		return NULL;
	}
#endif /* CONFIG_WIFI_DISPLAY */

	eloop_register_timeout(WPA_SUPPLICANT_CLEANUP_INTERVAL, 0,
			       wpas_periodic, global, NULL);

	return global;
}

其中有这么一句

	if (wpas_notify_supplicant_initialized(global)) {
		wpa_supplicant_deinit(global);
		return NULL;
	}

1.2 wpas_notify_supplicant_initialized

notify.c

int wpas_notify_supplicant_initialized(struct wpa_global *global)
{
#ifdef CONFIG_DBUS
	if (global->params.dbus_ctrl_interface) {
		global->dbus = wpas_dbus_init(global);
		if (global->dbus == NULL)
			return -1;
	}
#endif /* CONFIG_DBUS */

#ifdef CONFIG_HIDL
	global->hidl = wpas_hidl_init(global);
	if (!global->hidl)
		return -1;
#endif /* CONFIG_HIDL */

	return 0;
}

1.3 wpas_hidl_init

hidl.cpp

struct wpas_hidl_priv *wpas_hidl_init(struct wpa_global *global)
{
	struct wpas_hidl_priv *priv;
	HidlManager *hidl_manager;

	priv = (wpas_hidl_priv *)os_zalloc(sizeof(*priv));
	if (!priv)
		return NULL;
	priv->global = global;

	wpa_printf(MSG_DEBUG, "Initing hidl control");

	configureRpcThreadpool(1, true /* callerWillJoin */);
	IPCThreadState::self()->setupPolling(&priv->hidl_fd);
	if (priv->hidl_fd < 0)
		goto err;

	wpa_printf(MSG_INFO, "Processing hidl events on FD %d", priv->hidl_fd);
	// Look for read events from the hidl socket in the eloop.
	if (eloop_register_read_sock(
		priv->hidl_fd, wpas_hidl_sock_handler, global, priv) < 0)
		goto err;

	hidl_manager = HidlManager::getInstance();
	if (!hidl_manager)
		goto err;
	hidl_manager->registerHidlService(global);
	// We may not need to store this hidl manager reference in the
	// global data strucure because we've made it a singleton class.
	priv->hidl_manager = (void *)hidl_manager;

	return priv;
err:
	wpas_hidl_deinit(priv);
	return NULL;
}

1.4 registerHidlService

hidl_manager.cpp

int HidlManager::registerHidlService(struct wpa_global *global)
{
	// Create the main hidl service object and register it.
	supplicant_object_ = new Supplicant(global);
	if (supplicant_object_->registerAsService() != android::NO_ERROR) {
		return 1;
	}
	if (!supplicant_object_->ensureConfigFileExists()) {
		// If config file does not exist, we cannot start supplicant.
		return 1;
	}
	return 0;
}

1.5 ensureConfigFileExists

supplicant.cpp

bool Supplicant::ensureConfigFileExists()
{
	// To support Android P Wifi framework, make sure the config file exists.
	if (copyTemplateConfigFileIfNotExists(
		kStaIfaceConfPath, kTemplateConfPath) != 0) {
		wpa_printf(MSG_ERROR, "Conf file does not exists: %s",
		    kStaIfaceConfPath);
		return false;
	}
	// P2P configuration file is not madatory but required for some devices.
	if (copyTemplateConfigFileIfNotExists(
		kP2pIfaceConfPath, kTemplateConfPath) != 0) {
		wpa_printf(MSG_INFO, "Conf file does not exists: %s",
		    kP2pIfaceConfPath);
	}
	return true;
}

2. 总结