Function m_vsnprintf

Sming/System/m_printf.cpp:116–269

}

int m_vsnprintf(char *buf, size_t maxLen, const char *fmt, va_list args)
{
    size_t size = 0;
    auto add = [&](char c) {
        if (++size < maxLen) *buf++ = c;
    };

    while (*fmt) {
        //  copy verbatim text
        if (*fmt != '%')  {
            add(*fmt++);
            continue;
        }
        fmt++;

        const char* s;                          // source for string copy
        char    tempNum[40];                    // buffer for number conversion

        //  reset attributes to defaults
        bool    minus       = 0;
        uint8_t ubase       = 0;
        int8_t  precision   = -1;
        int8_t  width       = 0;
        char    pad         = ' ';
        uint8_t length      = 0;
        bool    upcase      = false;

        while (char f = *fmt) {
            if (f == '-')           minus = 1;
            else if (f == '+')      ;           // ignored
            else if (f == ' ')      ;           // ignored
            else if (f == '#')      ;           // ignored
            else                    break;
            fmt++;
        }

        //  process padding
        if (*fmt == '0') {
            pad = '0';
            fmt++;
        }

        //  process width ('*' is not supported yet)
        if ( is_digit(*fmt) ) {
            width = skip_atoi(&fmt);
        }

        //  process precision
        if( *fmt == '.' ) {
            fmt++;
            if ( is_digit(*fmt) ) precision = skip_atoi(&fmt);
        }

        // while (*fmt == 'l' || *fmt == 'h' || *fmt == 'L') fmt++;
        
        // process length
        do {
            if ( *fmt == 'l' ) {