initial import

string/strtok.c

@@ -0,0 +1,73 @@
+/* Copyright (C) 1991 Free Software Foundation, Inc.
+This file is part of the GNU C Library.
+
+The GNU C Library is free software; you can redistribute it and/or
+modify it under the terms of the GNU Library General Public License as
+published by the Free Software Foundation; either version 2 of the
+License, or (at your option) any later version.
+
+The GNU C Library is distributed in the hope that it will be useful,
+but WITHOUT ANY WARRANTY; without even the implied warranty of
+MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+Library General Public License for more details.
+
+You should have received a copy of the GNU Library General Public
+License along with the GNU C Library; see the file COPYING.LIB.  If
+not, write to the Free Software Foundation, Inc., 675 Mass Ave,
+Cambridge, MA 02139, USA.  */
+
+#include <ansidecl.h>
+#include <errno.h>
+#include <string.h>
+
+
+static char *olds = NULL;
+
+/* Parse S into tokens separated by characters in DELIM.
+   If S is NULL, the last string strtok() was called with is
+   used.  For example:
+	char s[] = "-abc=-def";
+	x = strtok(s, "-");		// x = "abc"
+	x = strtok(NULL, "=-");		// x = "def"
+	x = strtok(NULL, "=");		// x = NULL
+		// s = "abc\0-def\0"
+*/
+char *
+DEFUN(strtok, (s, delim),
+      register char *s AND register CONST char *delim)
+{
+  char *token;
+
+  if (s == NULL)
+    {
+      if (olds == NULL)
+	{
+	  errno = EINVAL;
+	  return NULL;
+	}
+      else
+	s = olds;
+    }
+
+  /* Scan leading delimiters.  */
+  s += strspn(s, delim);
+  if (*s == '\0')
+    {
+      olds = NULL;
+      return NULL;
+    }
+
+  /* Find the end of the token.  */
+  token = s;
+  s = strpbrk(token, delim);
+  if (s == NULL)
+    /* This token finishes the string.  */
+    olds = NULL;
+  else
+    {
+      /* Terminate the token and make OLDS point past it.  */
+      *s = '\0';
+      olds = s + 1;
+    }
+  return token;
+}