nsprpub/lib/libc/src/strchr.c

   1 /* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
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  37
  38 #include "plstr.h"
  39 #include <string.h>
  40
  41 PR_IMPLEMENT(char *)
  42 PL_strchr(const char *s, char c)
  43 {
  44     if( (const char *)0 == s ) return (char *)0;
  45
  46     return strchr(s, c);
  47 }
  48
  49 PR_IMPLEMENT(char *)
  50 PL_strrchr(const char *s, char c)
  51 {
  52     if( (const char *)0 == s ) return (char *)0;
  53
  54     return strrchr(s, c);
  55 }
  56
  57 PR_IMPLEMENT(char *)
  58 PL_strnchr(const char *s, char c, PRUint32 n)
  59 {
  60     if( (const char *)0 == s ) return (char *)0;
  61
  62     for( ; n && *s; s++, n-- )
  63         if( *s == c )
  64             return (char *)s;
  65
  66     if( ((char)0 == c) && (n > 0) && ((char)0 == *s) ) return (char *)s;
  67
  68     return (char *)0;
  69 }
  70
  71 PR_IMPLEMENT(char *)
  72 PL_strnrchr(const char *s, char c, PRUint32 n)
  73 {
  74     const char *p;
  75
  76     if( (const char *)0 == s ) return (char *)0;
  77
  78     for( p = s; n && *p; p++, n-- )
  79         ;
  80
  81     if( ((char)0 == c) && (n > 0) && ((char)0 == *p) ) return (char *)p;
  82
  83     for( p--; p >= s; p-- )
  84         if( *p == c )
  85             return (char *)p;
  86
  87     return (char *)0;
  88 }