strncat_s.c File Reference

#include "safe_str_lib.h"

Include dependency graph for strncat_s.c:

Functions
EXPORT errno_t	strncat_s (char *restrict dest, rsize_t dmax, const char *restrict src, rsize_t slen)
	The strncat_s function appends a copy of the string pointed to by src (including the terminating null character) to the end of the string pointed to by dest. More...

Function Documentation

strncat_s()

EXPORT errno_t strncat_s	(	char *restrict	dest,
		rsize_t	dmax,
		const char *restrict	src,
		rsize_t	slen
	)

The strncat_s function appends a copy of the string pointed to by src (including the terminating null character) to the end of the string pointed to by dest.

The initial character from src overwrites the null character at the end of dest.

All elements following the terminating null character (if any) written by strncat_s in the array of dmax characters pointed to by dest take unspecified values when strncat_s returns. With SAFECLIB_STR_NULL_SLACK defined the rest is cleared with NULL bytes.

Remarks

SPECIFIED IN

• C11 standard (ISO/IEC 9899:2011): K.3.7.2.2 The strncat_s function (p: 618-620) http://en.cppreference.com/w/c/string/byte/strncat
• ISO/IEC TR 24731, Programming languages, environments and system software interfaces, Extensions to the C Library, Part I: Bounds-checking interfaces

Parameters

[out]	dest	pointer to string that will be extended by src if dmax allows. The string is null terminated. If the resulting concatenated string is less than dmax, the remaining slack space is nulled.
[in]	dmax	restricted maximum length of the resulting dest, including the null
[in]	src	pointer to the string that will be concatenaed to string dest
[in]	slen	maximum characters to append

Precondition

Neither dest nor src shall be a null pointer

dmax shall not equal zero

dmax shall not be greater than RSIZE_MAX_STR

dmax shall be greater than strnlen_s(src,m).

Copying shall not takeplace between objects that overlap

Note

C11 uses RSIZE_MAX, not RSIZE_MAX_STR.

Returns

If there is a runtime-constraint violation, then if dest is not a null pointer and dmax is greater than zero and not greater than RSIZE_MAX_STR, then strncat_s sets dest[0] to the null character.

Return values

EOK	successful operation, all the characters from src null terminated.
ESNULLP	when dest/src is NULL pointer
ESZEROL	when dmax = 0
ESLEMAX	when dmax/slen > RSIZE_MAX_STR
ESUNTERM	when dest not terminated
ESOVRLP	when src overlaps with dest