_reactos_strsafe_wrapper.c File Reference

#include <windef.h>
#include <strsafe.h>

Include dependency graph for _reactos_strsafe_wrapper.c:

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Functions
int	_vsnprintf_s (char *buffer, size_t sizeOfBuffer, size_t count, const char *format, va_list argptr)

Function Documentation

_vsnprintf_s()

int _vsnprintf_s	(	char *	buffer,
		size_t	sizeOfBuffer,
		size_t	count,
		const char *	format,
		va_list	argptr
	)

Definition at line 25 of file _reactos_strsafe_wrapper.c.

{
    size_t cchRemaining;

    HRESULT ret = StringCchVPrintfEx(buffer, sizeOfBuffer, NULL, &cchRemaining, 0, format, argptr);

    // EXAMPLE //////////////////////////
    // -------- > Size of provided buffer in chars (8).
    // ABC0____ > Buffer contents after StringCchVPrintfEx gets called.
    // ---      > What we actually need to return (3).
    //    ----- > Remaining chars in buffer, including post string NULL, returned by StringCchVPrintfEx (5).

    /* _vsnprintf_s returns the number of characters written, not including
       the terminating null, or a negative value if an output error occurs.  */

    switch (ret)
    {
        case S_OK:
            return (sizeOfBuffer - cchRemaining);

        case STRSAFE_E_INVALID_PARAMETER:
        case STRSAFE_E_INSUFFICIENT_BUFFER:
        default:
            return -1;
    }
}