ardupilot/libraries/AP_HAL/Util.h

#ifndef __AP_HAL_UTIL_H__
#define __AP_HAL_UTIL_H__

#include <stdarg.h>
#include "AP_HAL_Namespace.h"
#include <AP_Progmem.h>

class AP_HAL::Util {
public:
    virtual int snprintf(char* str, size_t size,
            const char *format, ...) = 0;

    virtual int snprintf_P(char* str, size_t size,
            const prog_char_t *format, ...) = 0;

    virtual int vsnprintf(char* str, size_t size,
            const char *format, va_list ap) = 0;

    virtual int vsnprintf_P(char* str, size_t size,
            const prog_char_t *format, va_list ap) = 0;

    // run a debug shall on the given stream if possible. This is used
    // to support dropping into a debug shell to run firmware upgrade
    // commands
    virtual bool run_debug_shell(AP_HAL::BetterStream *stream) = 0;

};

#endif // __AP_HAL_UTIL_H__