esp8266/esp_mphal: Handle Ctrl+C from dupterm (e.g. WebREPL).

esp8266/esp_mphal.c

@@ -176,6 +176,10 @@ static int call_dupterm_read(void) {
             mp_uos_deactivate("dupterm: EOF received, deactivating\n", MP_OBJ_NULL);
             return -1;
         }
+        if (*(byte*)bufinfo.buf == interrupt_char) {
+            mp_keyboard_interrupt();
+            return -2;
+        }
         return *(byte*)bufinfo.buf;
     } else {
         mp_uos_deactivate("dupterm: Exception in read() method, deactivating: ", nlr.ret_val);

esp8266/esp_mphal.h

@@ -29,6 +29,9 @@
 
 #include "py/ringbuf.h"
 
+void mp_keyboard_interrupt(void);
+extern int interrupt_char;
+
 struct _mp_print_t;
 // Structure for UART-only output via mp_printf()
 extern const struct _mp_print_t mp_debug_print;