freebsd-dev/usr.sbin/sup/lib/skipto.c
Peter Wemm d14071a4b3 Import the unmodified version of the sup that we are using.
The heritage of this version is not clear.  It appears to be NetBSD
derived from some time ago.
1995-12-26 04:54:48 +00:00

79 lines
2.9 KiB
C

/*
* Copyright (c) 1991 Carnegie Mellon University
* All Rights Reserved.
*
* Permission to use, copy, modify and distribute this software and its
* documentation is hereby granted, provided that both the copyright
* notice and this permission notice appear in all copies of the
* software, derivative works or modified versions, and any portions
* thereof, and that both notices appear in supporting documentation.
*
* CARNEGIE MELLON ALLOWS FREE USE OF THIS SOFTWARE IN ITS "AS IS"
* CONDITION. CARNEGIE MELLON DISCLAIMS ANY LIABILITY OF ANY KIND FOR
* ANY DAMAGES WHATSOEVER RESULTING FROM THE USE OF THIS SOFTWARE.
*
* Carnegie Mellon requests users of this software to return to
*
* Software Distribution Coordinator or Software.Distribution@CS.CMU.EDU
* School of Computer Science
* Carnegie Mellon University
* Pittsburgh PA 15213-3890
*
* any improvements or extensions that they make and grant Carnegie the rights
* to redistribute these changes.
*/
/************************************************************************
* skipover and skipto -- skip over characters in string
*
* Usage: p = skipto (string,charset);
* p = skipover (string,charset);
*
* char *p,*charset,*string;
*
* Skipto returns a pointer to the first character in string which
* is in the string charset; it "skips until" a character in charset.
* Skipover returns a pointer to the first character in string which
* is not in the string charset; it "skips over" characters in charset.
************************************************************************
* HISTORY
* 26-Jun-81 David Smith (drs) at Carnegie-Mellon University
* Skipover, skipto rewritten to avoid inner loop at expense of space.
*
* 20-Nov-79 Steven Shafer (sas) at Carnegie-Mellon University
* Skipover, skipto adapted for VAX from skip() and skipx() on the PDP-11
* (from Ken Greer). The names are more mnemonic.
*
* Sindex adapted for VAX from indexs() on the PDP-11 (thanx to Ralph
* Guggenheim). The name has changed to be more like the index()
* and rindex() functions from Bell Labs; the return value (pointer
* rather than integer) has changed partly for the same reason,
* and partly due to popular usage of this function.
*/
static unsigned char tab[256] = {
0};
char *skipto (string,charset)
unsigned char *string, *charset;
{
register unsigned char *setp,*strp;
tab[0] = 1; /* Stop on a null, too. */
for (setp=charset; *setp; setp++) tab[*setp]=1;
for (strp=string; tab[*strp]==0; strp++) ;
for (setp=charset; *setp; setp++) tab[*setp]=0;
return ((char *)strp);
}
char *skipover (string,charset)
unsigned char *string, *charset;
{
register unsigned char *setp,*strp;
tab[0] = 0; /* Do not skip over nulls. */
for (setp=charset; *setp; setp++) tab[*setp]=1;
for (strp=string; tab[*strp]; strp++) ;
for (setp=charset; *setp; setp++) tab[*setp]=0;
return ((char *)strp);
}