Fixed a possibility that the function handler might be called twice

Configfs can use more than one configs.
(/sys/kernel/config/usb_gadget/hal-gadget/configs/hal-config.1 and /sys/kernel/config/usb_gadget/hal-gadget/configs/hal-config.2)

One usb function can be included in two config simultaneously.
In this situation, a handler associated with function can be called twice for a usb function.

To prevent duplicate calls,
it handles only the handlers of functions enabled in configfs, not the usb functions included in all configs.

Change-Id: I5e02dadc5d2688f0ad9210ad5ab149fb95ab05ba

1 files changed, 47 insertions, 45 deletions

diff --git a/hw/usb_cfs_client_common.c b/hw/usb_cfs_client_common.c
index 12e73c4..846eb77 100644
--- a/hw/usb_cfs_client_common.c
+++ b/hw/usb_cfs_client_common.c
@@ -16,8 +16,8 @@
  * limitations under the License.
  */
 
-#include <string.h>
 #include <errno.h>
+#include <string.h>
 #include <sys/stat.h>
 #include <sys/types.h>
 #include <sys/mount.h>
@@ -28,11 +28,6 @@
 
 #include <hw/usb_client.h>
 
-#define zalloc(amount) calloc(1, amount)
-
-#define MAX_GADGET_STR_LEN 256
-#define MAX_FUNCS 32
-
 #define CONFIGFS_PATH "/sys/kernel/config"
 
 #define CONFIGFS_GADGET_NAME "hal-gadget"
@@ -47,6 +42,12 @@
 #define EXPORT	__attribute__ ((visibility("default")))
 #endif
 
+enum cfs_function_service_operation {
+	CFS_FUNCTION_SERVICE_START,
+	CFS_FUNCTION_SERVICE_STOP,
+	CFS_FUNCTION_SERVICE_POST_STOP,
+};
+
 struct cfs_client {
 	struct usb_client client;
 	usbg_state *ctx;
@@ -556,48 +557,49 @@ out:
 	return ret;
 }
 
-static void cfs_start_stop_service_handler(usbg_gadget *gadget, bool start, bool post_stop)
+static void cfs_start_stop_service_and_handler(usbg_gadget *gadget, enum cfs_function_service_operation operation)
 {
 	int index;
 	const char *name;
 	const char *instance;
-	usbg_config *config;
-	usbg_binding *binding;
 	usbg_function *function;
 	struct usb_function *usb_function;
 
-	/* Execute service and handler related to functions bound to configs */
-	usbg_for_each_config(config, gadget) {
-		usbg_for_each_binding(binding, config) {
-			function = usbg_get_binding_target(binding);
-			instance = usbg_get_function_instance(function);
-			name = usbg_get_function_type_str(usbg_get_function_type(function));
-
-			index = cfs_find_func(name, instance);
-			if (index < 0)
-				continue;
-
-			usb_function = _available_funcs[index];
-
-			if (start) {
-				if (usb_function->handler)
-					usb_function->handler(1);
-
-				/* functionfs service is automatically started by socket activation */
-				if (!usb_function->is_functionfs && usb_function->service)
-					(void)systemd_start_unit_wait_started(usb_function->service, ".service", -1);
-			} else {
-				if (post_stop) {
-					if (usb_function->is_functionfs && usb_function->service)
-						(void)systemd_stop_unit_wait_stopped(usb_function->service, ".service", -1);
-				} else {
-					if (!usb_function->is_functionfs && usb_function->service)
-						(void)systemd_stop_unit_wait_stopped(usb_function->service, ".service", -1);
-
-					if (usb_function->handler)
-						usb_function->handler(0);
-				}
-			}
+	usbg_for_each_function(function, gadget) {
+		instance = usbg_get_function_instance(function);
+		name = usbg_get_function_type_str(usbg_get_function_type(function));
+
+		index = cfs_find_func(name, instance);
+		if (index < 0)
+			continue;
+
+		usb_function = _available_funcs[index];
+
+		switch(operation) {
+		case CFS_FUNCTION_SERVICE_START:
+			if (usb_function->handler)
+				usb_function->handler(1);
+
+			/* functionfs service is automatically started by socket activation */
+			if (!usb_function->is_functionfs && usb_function->service)
+				(void)systemd_start_unit_wait_started(usb_function->service, ".service", -1);
+			break;
+
+		case CFS_FUNCTION_SERVICE_STOP:
+			if (!usb_function->is_functionfs && usb_function->service)
+				(void)systemd_stop_unit_wait_stopped(usb_function->service, ".service", -1);
+
+			if (usb_function->handler)
+				usb_function->handler(0);
+			break;
+
+		case CFS_FUNCTION_SERVICE_POST_STOP:
+			if (usb_function->is_functionfs && usb_function->service)
+				(void)systemd_stop_unit_wait_stopped(usb_function->service, ".service", -1);
+			break;
+
+		default:
+			break;
 		}
 	}
 }
@@ -616,7 +618,7 @@ static int cfs_enable(struct usb_client *usb)
 	if (ret)
 		return ret;
 
-	cfs_start_stop_service_handler(cfs_client->gadget, true, false);
+	cfs_start_stop_service_and_handler(cfs_client->gadget, CFS_FUNCTION_SERVICE_START);
 
 	return 0;
 }
@@ -631,7 +633,7 @@ static int cfs_disable(struct usb_client *usb)
 
 	cfs_client = container_of(usb, struct cfs_client, client);
 
-	cfs_start_stop_service_handler(cfs_client->gadget, false, false);
+	cfs_start_stop_service_and_handler(cfs_client->gadget, CFS_FUNCTION_SERVICE_STOP);
 
 	ret = usbg_disable_gadget(cfs_client->gadget); /* ignore error checking */
 
@@ -640,7 +642,7 @@ static int cfs_disable(struct usb_client *usb)
 	 * If usb data may come in after stopping functionfs service and before disabling gadget,
 	 * functionfs service wakes up again by socket activation.
 	 */
-	cfs_start_stop_service_handler(cfs_client->gadget, false, true);
+	cfs_start_stop_service_and_handler(cfs_client->gadget, CFS_FUNCTION_SERVICE_POST_STOP);
 
 	return ret;
 }
@@ -655,7 +657,7 @@ int hw_cfs_gadget_open(struct hw_info *info,
 	if (!info || !common)
 		return -EINVAL;
 
-	cfs_client = zalloc(sizeof(*cfs_client));
+	cfs_client = calloc(1, sizeof(*cfs_client));
 	if (!cfs_client)
 		return -ENOMEM;