common/mbed/xprintf.cpp

   1 #include <cstdarg>
   2 //#include <stdarg.h>
   3 #include "mbed.h"
   4 #include "mbed/xprintf.h"
   5
   6
   7 #define STRING_STACK_LIMIT    120
   8
   9 /* mbed Serial */
  10 Serial ser(UART_TX, UART_RX);
  11
  12 /* TODO: Need small implementation for embedded */
  13 int xprintf(const char* format, ...)
  14 {
  15     /* copy from mbed/common/RawSerial.cpp */
  16     std::va_list arg;
  17     va_start(arg, format);
  18     int len = vsnprintf(NULL, 0, format, arg);
  19     if (len < STRING_STACK_LIMIT) {
  20         char temp[STRING_STACK_LIMIT];
  21         vsprintf(temp, format, arg);
  22         ser.puts(temp);
  23     } else {
  24         char *temp = new char[len + 1];
  25         vsprintf(temp, format, arg);
  26         ser.puts(temp);
  27         delete[] temp;
  28     }
  29     va_end(arg);
  30     return len;
  31
  32 /* Fail: __builtin_va_arg_pack?
  33  * https://gcc.gnu.org/onlinedocs/gcc-4.3.5/gcc/Constructing-Calls.html#Constructing-Calls
  34     void *arg = __builtin_apply_args();
  35     void *ret = __builtin_apply((void*)(&(ser.printf)), arg, 100);
  36     __builtin_return(ret)
  37 */
  38 /* Fail: varargs can not be passed to printf
  39     //int r = ser.printf("test %i\r\n", 123);
  40     va_list arg;
  41     va_start(arg, format);
  42     int r = ser.printf(format, arg);
  43     va_end(arg);
  44     return r;
  45 */
  46 }