//

// Copyright (c) Microsoft. All rights reserved.

// Licensed under the MIT license. See LICENSE file in the project root for full license information.

//

/***

*tcstok_s.inl - general implementation of _tcstok_s

*

*

*Purpose:

* This file contains the general algorithm for strtok_s and its variants.

*

****/

_FUNC_PROLOGUE

_CHAR * __cdecl _FUNC_NAME(_CHAR *_String, const _CHAR *_Control, _CHAR **_Context)

{

_CHAR *token;

const _CHAR *ctl;

/* validation section */

_VALIDATE_POINTER_ERROR_RETURN(_Context, EINVAL, NULL);

_VALIDATE_POINTER_ERROR_RETURN(_Control, EINVAL, NULL);

_VALIDATE_CONDITION_ERROR_RETURN(_String != NULL || *_Context != NULL, EINVAL, NULL);

/* If string==NULL, continue with previous string */

if (!_String)

{

_String = *_Context;

}

/* Find beginning of token (skip over leading delimiters). Note that

* there is no token iff this loop sets string to point to the terminal null. */

for ( ; *_String != 0 ; _String++)

{

for (ctl = _Control; *ctl != 0 && *ctl != *_String; ctl++)

;

if (*ctl == 0)

{

break;

}

}

token = _String;

/* Find the end of the token. If it is not the end of the string,

* put a null there. */

for ( ; *_String != 0 ; _String++)

{

for (ctl = _Control; *ctl != 0 && *ctl != *_String; ctl++)

;

if (*ctl != 0)

{

*_String++ = 0;

break;

}

}

/* Update the context */

*_Context = _String;

/* Determine if a token has been found. */

if (token == _String)

{

return NULL;

}

else

{

return token;

}

}