BSD 4_3_Tahoe release

[unix-history] / usr / src / bin / sh / args.c

#ifndef lint
static char sccsid[] = "@(#)args.c      4.5 4/24/88";
#endif

#
/*
* UNIX shell
*
* S. R. Bourne
* Bell Telephone Laboratories
*
*/

#include        "defs.h"

PROC DOLPTR copyargs();
LOCAL DOLPTR    dolh;

CHAR    flagadr[10];

CHAR    flagchar[] = {
       'x',    'n',    'v',    't',    's',    'i',    'e',    'r',    'k',    'u',    0
};
INT     flagval[]  = {
       execpr, noexec, readpr, oneflg, stdflg, intflg, errflg, rshflg, keyflg, setflg, 0
};

/* ========     option handling ======== */


INT     options(argc,argv)
       STRING          *argv;
       INT             argc;
{
       REG STRING      cp;
       REG STRING      *argp=argv;
       REG STRING      flagc;
       STRING          flagp;

       IF argc>1 ANDF *argp[1]=='-'
       THEN    cp=argp[1];
               flags &= ~(execpr|readpr);
               WHILE *++cp
               DO      flagc=flagchar;

                       WHILE *flagc ANDF *flagc != *cp DO flagc++ OD
                       IF *cp == *flagc
                       THEN    flags |= flagval[flagc-flagchar];
                       ELIF *cp=='c' ANDF argc>2 ANDF comdiv==0
                       THEN    comdiv=argp[2];
                               argp[1]=argp[0]; argp++; argc--;
                       ELSE    failed(argv[1],badopt);
                       FI
               OD
               argp[1]=argp[0]; argc--;
       FI

       /* set up $- */
       flagc=flagchar;
       flagp=flagadr;
       WHILE *flagc
       DO IF flags&flagval[flagc-flagchar]
          THEN *flagp++ = *flagc;
          FI
          flagc++;
       OD
       *flagp++=0;

       return(argc);
}

VOID    setargs(argi)
       STRING          argi[];
{
       /* count args */
       REG STRING      *argp=argi;
       REG INT         argn=0;

       WHILE Rcheat(*argp++)!=ENDARGS DO argn++ OD

       /* free old ones unless on for loop chain */
       freeargs(dolh);
       dolh=copyargs(argi,argn);       /* sets dolv */
       assnum(&dolladr,dolc=argn-1);
}

freeargs(blk)
       DOLPTR          blk;
{
       REG STRING      *argp;
       REG DOLPTR      argr=0;
       REG DOLPTR      argblk;

       IF argblk=blk
       THEN    argr = argblk->dolnxt;
               IF (--argblk->doluse)==0
               THEN    FOR argp=argblk->dolarg; Rcheat(*argp)!=ENDARGS; argp++
                       DO free(*argp) OD
                       free(argblk);
               FI
       FI
       return(argr);
}

LOCAL DOLPTR    copyargs(from, n)
       STRING          from[];
{
       REG DOLPTR      dp=alloc(sizeof(STRING*)*n+3*BYTESPERWORD);
       REG STRING *    np;
       REG STRING *    fp=from;

       dp->doluse=1;   /* use count */
       np=dp->dolarg;
       dolv=np;

       WHILE n--
       DO *np++ = make(*fp++) OD
       *np++ = ENDARGS;
       return(dp);
}

clearup()
{
       /* force `for' $* lists to go away */
       WHILE argfor=freeargs(argfor) DONE

       /* clean up io files */
       WHILE pop() DONE
}

DOLPTR  useargs()
{
       IF dolh
       THEN    dolh->doluse++;
               dolh->dolnxt=argfor;
               return(argfor=dolh);
       ELSE    return(0);
       FI
}