BSD 4_1c_2 release

[unix-history] / usr / src / old / sdb / access.c

static  char sccsid[] = "@(#)access.c 4.2 8/17/82";
#
/*
*
*      UNIX debugger
*
*/

#include "head.h"
struct user u;


MSG             BADDAT;
MSG             BADTXT;
MAP             txtmap;
MAP             datmap;
STRING          errflg;
int             errno;

INT             pid;




/* file handling and access routines */

int dmask[5] = {0, 0xff, 0xffff, 0xffffff, 0xffffffff};

/* get data at loc using descriptor format d */
long
getval(loc, d, space)
ADDR loc;
char d; {
       register int val;
       
       val = get(loc, space);
       val &= dmask[dtol(d)];
       return(val);
}

/* put value at loc using descriptor format d */
putval(loc, d, value)
ADDR loc; char d; long value; {
       register long val;
       
       val = get(loc, DSP);
       val = (val & !dmask[dtol(d)]) | (value & dmask[dtol(d)]);
       put(loc, DSP, val);
}

/* put value in named register using descriptor format d */
putreg(reg, d, value)
ADDR reg; char d; long value; {
       register long val;
       
       val = *(ADDR *)(((ADDR)&u)+R0+WORDSIZE*reg);
       val = (val & !dmask[dtol(d)]) | (value & dmask[dtol(d)]);
       *(ADDR *)(((ADDR)&u)+R0+WORDSIZE*reg) = val;
}

put(adr,space,value)
L_INT   adr;
{
       access(WT,adr,space,value);
}

POS     get(adr, space)
L_INT           adr;
{
       return(access(RD,adr,space,0));
}


access(mode,adr,space,value)
L_INT   adr;
{
       INT     pmode,rd,file;
       ADDR    w;
       if (debug) 
               printf("access(mode=%d,adr=%d,space=%d,value=%d) with pid %d\n",
                       mode, adr, space, value, pid);
       rd = mode==RD;

       IF space == NSP THEN return(0); FI

       IF pid          /* tracing on? */
       THEN
#ifndef vax
               IF adr&01 ANDF !rd THEN error(ODDADR); FI
#endif
            pmode = (space&DSP?(rd?RDUSER:WDUSER):(rd?RIUSER:WIUSER));
            w = ptrace(pmode, pid, adr, value);
            if (debug)
               printf("ptrace(%d,%d,%d,%d) = %d with error=%d\n",
                       pmode, pid, adr, value, w, errno);
#ifndef vax
            IF adr&01
            THEN w1 = ptrace(pmode, pid, shorten(adr+1), value);
                 w = (w>>8)&LOBYTE | (w1<<8);
            FI
#endif
            IF errno
            THEN errflg = (space&DSP ? BADDAT : BADTXT);
            FI
            return(w);
       FI
       w = 0;
       IF !chkmap(&adr,space)
       THEN return(0);
       FI
       file=(space&DSP?datmap.ufd:txtmap.ufd);
       if (longseek(file,adr)==0 ||
          (rd ? read(file,&w,sizeof(w)) : write(file,&value,sizeof(w))) < 1)
               errflg=(space&DSP?BADDAT:BADTXT);
       return(w);

}

chkmap(adr,space)
       REG L_INT       *adr;
       REG INT         space;
{
       REG MAPPTR amap;
       amap=((space&DSP?&datmap:&txtmap));
       IF space&STAR ORF !within(*adr,amap->b1,amap->e1)
       THEN if (within(*adr,amap->b2,amap->e2))
               *adr += (amap->f2)-(amap->b2);
            else {
               errflg=(space&DSP?BADDAT:BADTXT); return(0);
            }
       ELSE *adr += (amap->f1)-(amap->b1);
       FI
       return(1);
}

within(adr,lbd,ubd)
POS     adr, lbd, ubd;
{
       return(adr>=lbd && adr<ubd);
}

/* ------------ */
POS     chkget(n, space)
L_INT           n;
{
#ifndef vax
       REG INT         w;
#else
       REG L_INT       w;
#endif

       w = get(n, space);
       chkerr();
       return(w);
}

POS bchkget(n, space) 
L_INT   n;
{
       return(chkget(n, space) & LOBYTE);
}