int
cub_vsnprintf (char *buffer, size_t count, const char *format, va_list argptr)
{
int len = _vscprintf_p (format, argptr) + 1;
if (len > count)
{
char *cp = malloc (len);
if (cp == NULL)
{
return -1;
}
len = _vsprintf_p (cp, len, format, argptr);
if (len < 0)
{
free (cp);
return len;
}
memcpy (buffer, cp, count - 1);
buffer[count - 1] = 0;
free (cp);
return count;
}
return _vsprintf_p (buffer, count, format, argptr);
}
int __cdecl _scprintf_p(
const char* format,
...
) {
va_list arglist;
va_start(arglist, format);
return _vscprintf_p(format, arglist);
}
int
vasprintf (char **ptr, const char *format, va_list ap)
{
int len;
len = _vscprintf_p (format, ap) + 1;
*ptr = (char *) malloc (len * sizeof (char));
if (!*ptr)
{
return -1;
}
return _vsprintf_p (*ptr, len, format, ap);
}
int mt_snprintf(char *buf, const size_t buf_size, const char *fmt, ...)
{
// https://msdn.microsoft.com/en-us/library/bt7tawza.aspx
// Many of the MSVC / Windows printf-style functions do not support positional
// arguments (eg. "%1$s"). We just forward the call to vsnprintf for sane
// platforms, but defer to _vsprintf_p on MSVC / Windows.
// https://github.com/FFmpeg/FFmpeg/blob/5ae9fa13f5ac640bec113120d540f70971aa635d/compat/msvcrt/snprintf.c#L46
// _vsprintf_p has to be shimmed with _vscprintf_p on -1 (for an example see
// above FFmpeg link).
va_list args;
va_start(args, fmt);
#ifndef _MSC_VER
int c = vsnprintf(buf, buf_size, fmt, args);
#else // _MSC_VER
int c = _vsprintf_p(buf, buf_size, fmt, args);
if (c == -1)
c = _vscprintf_p(fmt, args);
#endif // _MSC_VER
va_end(args);
return c;
}
