strlen.c

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/***************************************************************************//**
 @file strlen.c
 
 @brief Defines the strlen function
*******************************************************************************/
#include <string.h>
 
/*******************************************************************************
 strlen
*//**
 @brief Computes the length of a string
 @param *s String having its length computed
 
 The strlen function computes the length of the string pointed to by s.
 
 @note If an error or wrapping occurs, a value of 0 is returned
 
 @return The number of characters that precede the terminating null character
*******************************************************************************/
size_t
strlen(const char *s)
{
 const char *end = s;
 
 /* Check s every time to safeguard against non-NUL terminated strings */
 while (end &&
 ('\0' != *end))
 {
 end++;
 }
 
 /* Verify the loop didn't stop in an error and s didn't wrap memory */
 if (!end ||
 (end < s))
 {
 end = s;
 }
 
 return (size_t) (end - s);
}