freebsd-dev/usr.sbin/sup/lib/nxtarg.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

78 lines
2.6 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.
*/
/*
* nxtarg -- strip off arguments from a string
*
* Usage: p = nxtarg (&q,brk);
* char *p,*q,*brk;
* extern char _argbreak;
*
* q is pointer to next argument in string
* after call, p points to string containing argument,
* q points to remainder of string
*
* Leading blanks and tabs are skipped; the argument ends at the
* first occurence of one of the characters in the string "brk".
* When such a character is found, it is put into the external
* variable "_argbreak", and replaced by a null character; if the
* arg string ends before that, then the null character is
* placed into _argbreak;
* If "brk" is 0, then " " is substituted.
*
* HISTORY
* 01-Jul-83 Steven Shafer (sas) at Carnegie-Mellon University
* Bug fix: added check for "back >= front" in loop to chop trailing
* white space.
*
* 20-Nov-79 Steven Shafer (sas) at Carnegie-Mellon University
* Rewritten for VAX. By popular demand, a table of break characters
* has been added (implemented as a string passed into nxtarg).
*
* Originally from klg (Ken Greer); IUS/SUS UNIX.
*/
char _argbreak;
char *skipto();
char *nxtarg (q,brk)
char **q,*brk;
{
register char *front,*back;
front = *q; /* start of string */
/* leading blanks and tabs */
while (*front && (*front == ' ' || *front == '\t')) front++;
/* find break character at end */
if (brk == 0) brk = " ";
back = skipto (front,brk);
_argbreak = *back;
*q = (*back ? back+1 : back); /* next arg start loc */
/* elim trailing blanks and tabs */
back -= 1;
while ((back >= front) && (*back == ' ' || *back == '\t')) back--;
back++;
if (*back) *back = '\0';
return (front);
}