strrchr.c

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/***************************************************************************//**
 @file strrchr.c
 
 @brief Defines the strrchr function
*******************************************************************************/
#include <string.h>
 
/*******************************************************************************
 strrchr
*//**
 @brief Locate the last occurrence of a character in a string
 @param *s String being searched
 @param c Character to find
 
 The strrchr function locates the last occurrence of c (converted to a
 char) in the string pointed to by s. The terminating null character is
 considered to be a part of the string.
 
 @return A pointer to the located character
 @retval NULL The character does not occur in the string
*******************************************************************************/
char *
strrchr(const char *s, int c)
{
 const char *cur = NULL;
 const char search = c;
 
 if (!s)
 {
 return NULL;
 }
 
 cur = s + strlen(s);
 do
 {
 if (search == *cur)
 {
 return (char *) cur;
 }
 
 } while (--cur >= s);
 
 return NULL;
}