1 /* Reentrant string tokenizer.  Generic version.
2    Copyright (C) 1991-2022 Free Software Foundation, Inc.
3    This file is part of the GNU C Library.
4 
5    The GNU C Library is free software; you can redistribute it and/or
6    modify it under the terms of the GNU Lesser General Public
7    License as published by the Free Software Foundation; either
8    version 2.1 of the License, or (at your option) any later version.
9 
10    The GNU C Library is distributed in the hope that it will be useful,
11    but WITHOUT ANY WARRANTY; without even the implied warranty of
12    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
13    Lesser General Public License for more details.
14 
15    You should have received a copy of the GNU Lesser General Public
16    License along with the GNU C Library; if not, see
17    <https://www.gnu.org/licenses/>.  */
18 
19 #ifdef HAVE_CONFIG_H
20 # include <config.h>
21 #endif
22 
23 #include <string.h>
24 
25 #ifndef _LIBC
26 /* Get specification.  */
27 # include "strtok_r.h"
28 # define __strtok_r strtok_r
29 #endif
30 
31 /* Parse S into tokens separated by characters in DELIM.
32    If S is NULL, the saved pointer in SAVE_PTR is used as
33    the next starting point.  For example:
34 	char s[] = "-abc-=-def";
35 	char *sp;
36 	x = strtok_r(s, "-", &sp);	// x = "abc", sp = "=-def"
37 	x = strtok_r(NULL, "-=", &sp);	// x = "def", sp = NULL
38 	x = strtok_r(NULL, "=", &sp);	// x = NULL
39 		// s = "abc\0-def\0"
40 */
41 char *
__strtok_r(char * s,const char * delim,char ** save_ptr)42 __strtok_r (char *s, const char *delim, char **save_ptr)
43 {
44   char *end;
45 
46   if (s == NULL)
47     s = *save_ptr;
48 
49   if (*s == '\0')
50     {
51       *save_ptr = s;
52       return NULL;
53     }
54 
55   /* Scan leading delimiters.  */
56   s += strspn (s, delim);
57   if (*s == '\0')
58     {
59       *save_ptr = s;
60       return NULL;
61     }
62 
63   /* Find the end of the token.  */
64   end = s + strcspn (s, delim);
65   if (*end == '\0')
66     {
67       *save_ptr = end;
68       return s;
69     }
70 
71   /* Terminate the token and make *SAVE_PTR point past it.  */
72   *end = '\0';
73   *save_ptr = end + 1;
74   return s;
75 }
76 #ifdef weak_alias
77 libc_hidden_def (__strtok_r)
78 weak_alias (__strtok_r, strtok_r)
79 #endif
80