luckfox-pico-sdk/project/app/wifi_app/hisi_tools/securec/strtok_s.c
2023-08-08 20:36:47 +08:00

110 lines
3.3 KiB
C

/*
* Copyright (c) Huawei Technologies Co., Ltd. 2014-2018. All rights reserved.
* Description: strtok_s function
* Author: lishunda
* Create: 2014-02-25
*/
#include "securecutil.h"
SECUREC_INLINE int SecIsInDelimit(char ch, const char *strDelimit) {
const char *ctl = strDelimit;
while (*ctl != '\0' && *ctl != ch) {
++ctl;
}
return (int)(*ctl != '\0');
}
/*
* Find beginning of token (skip over leading delimiters).
* Note that there is no token if this loop sets string to point to the terminal
* null.
*/
SECUREC_INLINE char *SecFindBegin(char *strToken, const char *strDelimit) {
char *token = strToken;
while (*token != '\0') {
if (SecIsInDelimit(*token, strDelimit)) {
++token;
continue;
}
/* Don't find any delimiter in string header, break the loop */
break;
}
return token;
}
/*
* Find rest of token
*/
SECUREC_INLINE char *SecFindRest(char *strToken, const char *strDelimit) {
/* Find the rest of the token. If it is not the end of the string, put a null
* there */
char *token = strToken;
while (*token != '\0') {
if (SecIsInDelimit(*token, strDelimit)) {
/* Find a delimiter, set string termintor */
*token = '\0';
++token;
break;
}
++token;
}
return token;
}
/*
* Find the final position pointer
*/
SECUREC_INLINE char *SecUpdateToken(char *strToken, const char *strDelimit,
char **context) {
/* Point to updated position */
char *token = SecFindRest(strToken, strDelimit);
/* Record string position for next search in the context */
*context = token;
/* Determine if a token has been found. */
if (token == strToken) {
return NULL;
}
return strToken;
}
/*
* <FUNCTION DESCRIPTION>
* The strtok_s function parses a string into a sequence of strToken,
* replace all characters in strToken string that match to strDelimit set
* with 0. On the first call to strtok_s the string to be parsed should be
* specified in strToken. In each subsequent call that should parse the same
* string, strToken should be NULL <INPUT PARAMETERS> strToken String
* containing token or tokens. strDelimit Set of delimiter characters.
* context Used to store position information between calls
* to strtok_s
* <OUTPUT PARAMETERS>
* context is updated
* <RETURN VALUE>
* On the first call returns the address of the first non \0 character,
* otherwise NULL is returned. In subsequent calls, the strtoken is set to NULL,
* and the context set is the same as the previous call, return NULL if the
* *context string length is equal 0, otherwise return *context.
*/
char *strtok_s(char *strToken, const char *strDelimit, char **context) {
char *orgToken = strToken;
/* Validate delimiter and string context */
if (context == NULL || strDelimit == NULL) {
return NULL;
}
/* Valid input string and string pointer from where to search */
if (orgToken == NULL && *context == NULL) {
return NULL;
}
/* If string is null, continue searching from previous string position stored
* in context */
if (orgToken == NULL) {
orgToken = *context;
}
orgToken = SecFindBegin(orgToken, strDelimit);
return SecUpdateToken(orgToken, strDelimit, context);
}
#if SECUREC_IN_KERNEL
EXPORT_SYMBOL(strtok_s);
#endif