Merge "adb: avoid potential race conditions in detecting device disconnects" (fc86c58a) · Commits · e / os / android_system_core

adb/usb_linux.c

+33 −32

Original line number	Diff line number	Diff line
		@@ -81,13 +81,41 @@ static int known_device(const char *dev_name)

		static void kick_disconnected_device(const char devname, void client_data)
		{
		usb_handle *usb;
		usb_handle *h;

		adb_mutex_lock(&usb_lock);
		/* kick the device if it is in our list */
		for (usb = handle_list.next; usb != &handle_list; usb = usb->next) {
		if (!strcmp(devname, usb_device_get_name(usb->device)))
		usb_kick(usb);
		for (h = handle_list.next; h != &handle_list; h = h->next) {
		if (!strcmp(devname, usb_device_get_name(h->device))) {
		D("[ kicking %p (fd = %s) ]\n", h, usb_device_get_name(h->device));
		adb_mutex_lock(&h->lock);
		if(h->dead == 0) {
		h->dead = 1;

		if (usb_device_is_writeable(h->device)) {
		/* HACK ALERT!
		** Sometimes we get stuck in ioctl(USBDEVFS_REAPURB).
		** This is a workaround for that problem.
		*/
		if (h->reaper_thread) {
		pthread_kill(h->reaper_thread, SIGALRM);
		}

		/* cancel any pending transactions
		** these will quietly fail if the txns are not active,
		** but this ensures that a reader blocked on REAPURB
		** will get unblocked
		*/
		usb_endpoint_cancel(h->ep_in);
		usb_endpoint_cancel(h->ep_out);
		adb_cond_broadcast(&h->notify_in);
		adb_cond_broadcast(&h->notify_out);
		} else {
		unregister_usb_transport(h);
		}
		}
		adb_mutex_unlock(&h->lock);
		}
		}
		adb_mutex_unlock(&usb_lock);

		@@ -405,34 +433,7 @@ int usb_read(usb_handle h, void _data, int len)

		void usb_kick(usb_handle *h)
		{
		D("[ kicking %p (fd = %s) ]\n", h, usb_device_get_name(h->device));
		adb_mutex_lock(&h->lock);
		if(h->dead == 0) {
		h->dead = 1;

		if (usb_device_is_writeable(h->device)) {
		/* HACK ALERT!
		** Sometimes we get stuck in ioctl(USBDEVFS_REAPURB).
		** This is a workaround for that problem.
		*/
		if (h->reaper_thread) {
		pthread_kill(h->reaper_thread, SIGALRM);
		}

		/* cancel any pending transactions
		** these will quietly fail if the txns are not active,
		** but this ensures that a reader blocked on REAPURB
		** will get unblocked
		*/
		usb_endpoint_cancel(h->ep_in);
		usb_endpoint_cancel(h->ep_out);
		adb_cond_broadcast(&h->notify_in);
		adb_cond_broadcast(&h->notify_out);
		} else {
		unregister_usb_transport(h);
		}
		}
		adb_mutex_unlock(&h->lock);
		// do nothing here. we kick in kick_disconnected_devices instead.
		}

		int usb_close(usb_handle *h)