made SerialUSB.read blocking

it should have been blocking before but wasnt. see bug #49

1 files changed, 12 insertions, 2 deletions

diff --git a/wirish/usb_serial.cpp b/wirish/usb_serial.cpp
index 5c8a65f..d4a8148 100644
--- a/wirish/usb_serial.cpp
+++ b/wirish/usb_serial.cpp
@@ -101,17 +101,27 @@ uint32 USBSerial::available(void) {
     return usbBytesAvailable();
 }
 
+/* blocks forever until len_bytes is received */
 uint32 USBSerial::read(void *buf, uint32 len) {
     if (!buf) {
         return 0;
     }
 
-    return usbReceiveBytes((uint8*)buf, len);
+    uint32 bytes_in = 0;
+    while (len > 0) {
+        uint32 new_bytes = usbReceiveBytes(&(uint8)buf[new_bytes], len);
+        len -= newBytes;
+        bytes_in += new_bytes;
+    }
+
+    return len;
 }
 
+/* blocks forever until 1 byte is received */
 uint8 USBSerial::read(void) {
     uint8 ch;
-    usbReceiveBytes(&ch, 1);
+
+    while (usbReceiveBytes(&ch, 1) == 0);
     return ch;
 }