dist/ntp/libopts/compat/strchr.c

   1 /*      $NetBSD$        */
   2
   3 /*
   4    SYNOPSIS
   5        #include <string.h>
   6
   7        char *strchr(char const *s, int c);
   8
   9        char *strrchr(char const *s, int c);
  10
  11    DESCRIPTION
  12        The  strchr() function returns a pointer to the first occurrence of the
  13        character c in the string s.
  14
  15        The strrchr() function returns a pointer to the last occurrence of  the
  16        character c in the string s.
  17
  18        Here  "character"  means "byte" - these functions do not work with wide
  19        or multi-byte characters.
  20
  21    RETURN VALUE
  22        The strchr() and strrchr() functions return a pointer  to  the  matched
  23        character or NULL if the character is not found.
  24
  25    CONFORMING TO
  26        SVID 3, POSIX, BSD 4.3, ISO 9899
  27 */
  28
  29 char*
  30 strchr( char const *s, int c)
  31 {
  32     do {
  33         if ((unsigned)*s == (unsigned)c)
  34             return s;
  35
  36     } while (*(++s) != NUL);
  37
  38     return NULL;
  39 }
  40
  41 char*
  42 strrchr( char const *s, int c)
  43 {
  44     char const *e = s + strlen(s);
  45
  46     for (;;) {
  47         if (--e < s)
  48             break;
  49
  50         if ((unsigned)*e == (unsigned)c)
  51             return e;
  52     }
  53     return NULL;
  54 }
  55
  56 /*
  57  * Local Variables:
  58  * mode: C
  59  * c-file-style: "stroustrup"
  60  * indent-tabs-mode: nil
  61  * End:
  62  * end of compat/strsignal.c */