gistfile1.cpp

#include <stdio.h>
#include <string>

template< class > struct FormatSupportedType;

#define SUPPORTED_TYPE(C, T) \
template<> struct FormatSupportedType< T > { \
constexpr static bool supports(char c) { return c == C; } }

SUPPORTED_TYPE('c', char);
SUPPORTED_TYPE('d', int);
SUPPORTED_TYPE('f', float);

template< std::size_t N >
constexpr bool checkFormatHelper(const char (&format)[N], std::size_t current)
{
    return
    current >= N ?
    true
    : format[current] != '%' ?
    checkFormatHelper( format, current + 1 )
    : format[current + 1] == '%' ?
    checkFormatHelper( format, current + 2 )
    :
    false;
}

template< std::size_t N, class T, class... Ts >
constexpr bool checkFormatHelper(const char (&format)[N], std::size_t current, const T& arg, const Ts & ... args)
{
    return
    current >= N ?
    false
    : format[current] != '%' ?
    checkFormatHelper( format, current + 1, arg, args... )
    : (format[current] == '%' && format[current + 1] == '%') ?
    checkFormatHelper( format, current + 2, arg, args... )
    : FormatSupportedType< T >::supports(format[current + 1]) &&
    checkFormatHelper( format, current + 2, args... );
}

template< std::size_t N, class... Ts >
constexpr bool checkFormat(const char (&format)[N], const Ts & ... args)
{
    return checkFormatHelper( format, 0, args... );
}

#define safe_printf(FORMAT, ...) \
static_assert(checkFormat( FORMAT, __VA_ARGS__ ), "Format is incorrect"); \
printf(FORMAT, __VA_ARGS__)

int main(int argc, const char * argv[])
{

    safe_printf("test %% %f %d\n", 1.0f, 1);
    return 0;
}