toolchain/gcc/newlib/libc/string/strtok.c

   1 /*
   2 FUNCTION
   3         <<strtok>>,<<strtok_r>>,<<strsep>>---get next token from a string
   4
   5 INDEX
   6         strtok
   7
   8 INDEX
   9         strtok_r
  10
  11 INDEX
  12         strsep
  13
  14 ANSI_SYNOPSIS
  15         #include <string.h>
  16         char *strtok(char *<[source]>, const char *<[delimiters]>)
  17         char *strtok_r(char *<[source]>, const char *<[delimiters]>,
  18                         char **<[lasts]>)
  19         char *strsep(char **<[source_ptr]>, const char *<[delimiters]>)
  20
  21 TRAD_SYNOPSIS
  22         #include <string.h>
  23         char *strtok(<[source]>, <[delimiters]>)
  24         char *<[source]>;
  25         char *<[delimiters]>;
  26
  27         char *strtok_r(<[source]>, <[delimiters]>, <[lasts]>)
  28         char *<[source]>;
  29         char *<[delimiters]>;
  30         char **<[lasts]>;
  31
  32         char *strsep(<[source_ptr]>, <[delimiters]>)
  33         char **<[source_ptr]>;
  34         char *<[delimiters]>;
  35
  36 DESCRIPTION
  37         The <<strtok>> function is used to isolate sequential tokens in a
  38         null-terminated string, <<*<[source]>>>. These tokens are delimited
  39         in the string by at least one of the characters in <<*<[delimiters]>>>.
  40         The first time that <<strtok>> is called, <<*<[source]>>> should be
  41         specified; subsequent calls, wishing to obtain further tokens from
  42         the same string, should pass a null pointer instead.  The separator
  43         string, <<*<[delimiters]>>>, must be supplied each time, and may
  44         change between calls.
  45
  46         The <<strtok>> function returns a pointer to the beginning of each
  47         subsequent token in the string, after replacing the separator
  48         character itself with a NUL character.  When no more tokens remain,
  49         a null pointer is returned.
  50
  51         The <<strtok_r>> function has the same behavior as <<strtok>>, except
  52         a pointer to placeholder <<*[lasts]>> must be supplied by the caller.
  53
  54         The <<strsep>> function is similar in behavior to <<strtok>>, except
  55         a pointer to the string pointer must be supplied <<[source_ptr]>> and
  56         the function does not skip leading delimeters.  When the string starts
  57         with a delimeter, the delimeter is changed to the NUL character and
  58         the empty string is returned.  Like <<strtok_r>> and <<strtok>>, the
  59         <<*[source_ptr]>> is updated to the next character following the
  60         last delimeter found or NULL if the end of string is reached with
  61         no more delimeters.
  62
  63 RETURNS
  64         <<strtok>>, <<strtok_r>>, and <<strsep>> all return a pointer to the
  65         next token, or <<NULL>> if no more tokens can be found.  For
  66         <<strsep>>, a token may be the empty string.
  67
  68 NOTES
  69         <<strtok>> is unsafe for multi-thread applications.  <<strtok_r>>
  70         and <<strsep>> are MT-Safe and should be used instead.
  71
  72 PORTABILITY
  73 <<strtok>> is ANSI C.
  74 <<strtok_r>> is POSIX.
  75 <<strsep>> is a BSD-extension.
  76
  77 <<strtok>>, <<strtok_r>>, and <<strsep>> require no supporting OS subroutines.
  78
  79 QUICKREF
  80         strtok ansi impure
  81 */
  82
  83 /* undef STRICT_ANSI so that strtok_r prototype will be defined */
  84 #undef  __STRICT_ANSI__
  85 #include <string.h>
  86 #include <_ansi.h>
  87 #include <reent.h>
  88
  89 #ifndef _REENT_ONLY
  90
  91 extern char *__strtok_r (char *, const char *, char **, int);
  92
  93 char *
  94 _DEFUN (strtok, (s, delim),
  95         register char *s _AND
  96         register const char *delim)
  97 {
  98         _REENT_CHECK_MISC(_REENT);
  99         return __strtok_r (s, delim, &(_REENT_STRTOK_LAST(_REENT)), 1);
 100 }
 101 #endif