vsprintf_s.c File Reference

#include "safe_str_lib.h"

Include dependency graph for vsprintf_s.c:

Functions
EXPORT int	vsprintf_s (char *restrict dest, rsize_t dmax, const char *restrict fmt, va_list ap)
	The vsprintf_s function composes a string with same test that would be printed if format was used on printf. More...

Function Documentation

vsprintf_s()

EXPORT int vsprintf_s	(	char *restrict	dest,
		rsize_t	dmax,
		const char *restrict	fmt,
		va_list	ap
	)

The vsprintf_s function composes a string with same test that would be printed if format was used on printf.

Instead of being printed, the content is stored in dest. With SAFECLIB_STR_NULL_SLACK defined all elements following the terminating null character (if any) written by vsprintf_s in the array of dmax characters pointed to by dest are nulled when vsprintf_s returns.

Remarks

SPECIFIED IN

• C11 standard (ISO/IEC 9899:2011): K.3.5.3.13 The vsprintf_s function (p: 601) http://en.cppreference.com/w/c/io/vfprintf

Parameters

[out]	dest	pointer to string that will be written into.
[in]	dmax	restricted maximum length of dest
[in]	fmt	format-control string.
[in]	ap	optional arguments

Precondition

Neither dest nor fmt shall be a null pointer.

dmax shall not be greater than RSIZE_MAX_STR.

dmax shall not equal zero.

dmax shall be greater than strnlen_s(dest, dmax).

fmt shall not contain the conversion specifier n

None of the arguments corresponding to s is a null pointer

No encoding error shall occur.

Note

C11 uses RSIZE_MAX, not RSIZE_MAX_STR.

Returns

On success the total number of characters written is returned.

On failure a negative number is returned.

If the buffer dest is too small for the formatted text, including the terminating null, then the buffer is set to an empty string by placing a null character at dest[0], and the invalid parameter handler is invoked. Unlike vsnprintf, vsprintf_s guarantees that the buffer will be null-terminated unless the buffer size is zero.

errno: ESNULLP when dest/fmt is NULL pointer ESZEROL when dmax = 0 ESLEMAX when dmax > RSIZE_MAX_STR ESNOSPC when return value exceeds dmax EINVAL when fmt contains n

Return values

-1	if an encoding error occurred or the return buffer size exceeds dmax.
0	on some other error in vsnprintf().

See also

sprintf_s(), vsnprintf_s()