Interrupt blocking threads when changing altsetting/interface

Disable endpoint before attempting to join threads that might be
blocked on read/write Raw Gadget ioctls.

Hopefully fixes AristoChen#9.

host-raw-gadget.cpp

@@ -107,8 +107,10 @@ int usb_raw_ep_read(int fd, struct usb_raw_ep_io *io) {
 			// Ignore failures caused by the test that halts endpoints.
 			return rv;
 		}
-		else if (errno == EBUSY)
+		else if (errno == EBUSY || errno == ESHUTDOWN) {
+			// Ignore failures caused by thread cancellation.
 			return rv;
+		}
 		perror("ioctl(USB_RAW_IOCTL_EP_READ)");
 		exit(EXIT_FAILURE);
 	}
@@ -122,8 +124,10 @@ int usb_raw_ep_write(int fd, struct usb_raw_ep_io *io) {
 			// Ignore failures caused by the test that halts endpoints.
 			return rv;
 		}
-		else if (errno == EBUSY)
+		else if (errno == EBUSY || errno == ESHUTDOWN) {
+			// Ignore failures caused by thread cancellation.
 			return rv;
+		}
 		perror("ioctl(USB_RAW_IOCTL_EP_WRITE)");
 		exit(EXIT_FAILURE);
 	}
@@ -315,7 +319,7 @@ void log_event(struct usb_raw_event *event) {
 		log_control_request((struct usb_ctrlrequest *)&event->data[0]);
 		break;
 	default:
-		printf("event: unknown, length: %u\n", event->length);
+		printf("event: unknown (%d), length: %u\n", (int)event->type, event->length);
 	}
 }
 

misc.h

@@ -15,7 +15,7 @@
 
 extern int verbose_level;
 extern bool please_stop_ep0;
-extern bool please_stop_eps;
+extern volatile bool please_stop_eps;
 
 extern bool injection_enabled;
 extern std::string injection_file;

proxy.cpp

@@ -129,7 +129,16 @@ void *ep_loop_write(void *arg) {
 
 		if (ep.bEndpointAddress & USB_DIR_IN) {
 			int rv = usb_raw_ep_write(fd, (struct usb_raw_ep_io *)&io);
-			if (rv >= 0) {
+			if (rv < 0 && please_stop_eps) {
+				printf("EP%x(%s_%s): thread interrupted\n", ep.bEndpointAddress,
+						transfer_type.c_str(), dir.c_str());
+				break;
+			}
+			else if (rv < 0) {
+				perror("usb_raw_ep_write()");
+				exit(EXIT_FAILURE);
+			}
+			else {
 				printf("EP%x(%s_%s): wrote %d bytes to host\n", ep.bEndpointAddress,
 					transfer_type.c_str(), dir.c_str(), rv);
 			}
@@ -204,7 +213,16 @@ void *ep_loop_read(void *arg) {
 			io.inner.length = sizeof(io.data);
 
 			int rv = usb_raw_ep_read(fd, (struct usb_raw_ep_io *)&io);
-			if (rv >= 0) {
+			if (rv < 0 && please_stop_eps) {
+				printf("EP%x(%s_%s): thread interrupted\n", ep.bEndpointAddress,
+						transfer_type.c_str(), dir.c_str());
+				break;
+			}
+			else if (rv < 0) {
+				perror("usb_raw_ep_read()");
+				exit(EXIT_FAILURE);
+			}
+			else {
 				printf("EP%x(%s_%s): read %d bytes from host\n", ep.bEndpointAddress,
 						transfer_type.c_str(), dir.c_str(), rv);
 				io.inner.length = rv;
@@ -291,6 +309,8 @@ void terminate_eps(int fd, int config, int interface, int altsetting) {
 	for (int i = 0; i < alt->interface.bNumEndpoints; i++) {
 		struct raw_gadget_endpoint *ep = &alt->endpoints[i];
 
+		usb_raw_ep_disable(fd, ep->thread_info.ep_num);
+
 		if (ep->thread_read && pthread_join(ep->thread_read, NULL)) {
 			fprintf(stderr, "Error join thread_read\n");
 		}
@@ -300,7 +320,6 @@ void terminate_eps(int fd, int config, int interface, int altsetting) {
 		ep->thread_read = 0;
 		ep->thread_write = 0;
 
-		usb_raw_ep_disable(fd, ep->thread_info.ep_num);
 		ep->thread_info.ep_num = -1;
 
 		delete ep->thread_info.data_queue;

usb-proxy.cpp

@@ -5,7 +5,7 @@
 
 int verbose_level = 0;
 bool please_stop_ep0 = false;
-bool please_stop_eps = false;
+volatile bool please_stop_eps = false; // Use volatile to mark as atomic.
 
 bool injection_enabled = false;
 std::string injection_file = "injection.json";