2.9BSD - /usr/src/cmd/adb/access.c

   1: #
   2: /*
   3:  *
   4:  *	UNIX debugger
   5:  *
   6:  */
   7: 
   8: #include "defs.h"
   9: 
  10: 
  11: MSG     ODDADR;
  12: MSG     BADDAT;
  13: MSG     BADTXT;
  14: MAP     txtmap;
  15: MAP     datmap;
  16: INT     wtflag;
  17: STRING      errflg;
  18: INT     errno;
  19: 
  20: INT     pid;
  21: 
  22: struct ovhead       ovlseg;
  23: L_INT       ovloff[];
  24: OVTAG       curov;
  25: int     overlay;
  26: 
  27: L_INT       var[];
  28: 
  29: 
  30: 
  31: /* file handling and access routines */
  32: 
  33: put(adr,space,value)
  34: L_INT   adr;
  35: {
  36:     access(WT,adr,space,value);
  37: }
  38: 
  39: POS get(adr, space)
  40: L_INT       adr;
  41: {
  42:     return(access(RD,adr,space,0));
  43: }
  44: 
  45: POS chkget(n, space)
  46: L_INT       n;
  47: {
  48:     REG INT     w;
  49: 
  50:     w = get(n, space);
  51:     chkerr();
  52:     return(w);
  53: }
  54: 
  55: access(mode,adr,space,value)
  56: L_INT   adr;
  57: {
  58:     INT     w, w1, pmode, rd, file;
  59:     BKPTR   bkptr, scanbkpt();
  60:     rd = mode==RD;
  61: 
  62:     IF space == NSP THEN return(0); FI
  63: 
  64:     IF pid      /* tracing on? */
  65:     THEN IF (adr&01) ANDF !rd THEN error(ODDADR); FI
  66:          pmode = (space&DSP?(rd?RDUSER:WDUSER):(rd?RIUSER:WIUSER));
  67:          if (bkptr=scanbkpt((POS)adr)) {
  68:         if (rd) {
  69:             return(bkptr->ins);
  70:         } else {
  71:             bkptr->ins = value;
  72:             return(0);
  73:         }
  74:          }
  75:          w = ptrace(pmode, pid, shorten(adr&~01), value);
  76:          IF adr&01
  77:          THEN w1 = ptrace(pmode, pid, shorten(adr+1), value);
  78:           w = (w>>8)&LOBYTE | (w1<<8);
  79:          FI
  80:          IF errno
  81:          THEN errflg = (space&DSP ? BADDAT : BADTXT);
  82:          FI
  83:          return(w);
  84:     FI
  85:     w = 0;
  86:     IF mode==WT ANDF wtflag==0
  87:     THEN    error("not in write mode");
  88:     FI
  89:     IF !chkmap(&adr,space)
  90:     THEN return(0);
  91:     FI
  92:     file=(space&DSP?datmap.ufd:txtmap.ufd);
  93:     IF longseek(file,adr)==0 ORF
  94:        (rd ? read(file,&w,2) : write(file,&value,2)) < 1
  95:     THEN    errflg=(space&DSP?BADDAT:BADTXT);
  96:     FI
  97:     return(w);
  98: 
  99: }
 100: 
 101: chkmap(adr,space)
 102:     REG L_INT   *adr;
 103:     REG INT     space;
 104: {
 105:     REG MAPPTR amap;
 106:     amap=((space&DSP?&datmap:&txtmap));
 107:     switch(space&(ISP|DSP|STAR)) {
 108: 
 109:         case ISP:
 110:             IF within(*adr, amap->b1, amap->e1)
 111:             THEN *adr += (amap->f1) - (amap->b1);
 112:                 break;
 113:             ELIF within(*adr, amap->bo, amap->eo)
 114:             THEN *adr += (amap->fo) - (amap->bo);
 115:                 break;
 116:             FI
 117:             /* falls through */
 118: 
 119:         case ISP+STAR:
 120:             IF within(*adr, amap->b2, amap->e2)
 121:             THEN *adr += (amap->f2) - (amap->b2);
 122:                 break;
 123:             ELSE goto error;
 124:             FI
 125: 
 126:         case DSP:
 127:             IF within(*adr, amap->b1, amap->e1)
 128:             THEN *adr += (amap->f1) - (amap->b1);
 129:                 break;
 130:             FI
 131:             /* falls through */
 132: 
 133:         case DSP+STAR:
 134:             IF within(*adr, amap->b2, amap->e2)
 135:             THEN *adr += (amap->f2) - (amap->b2);
 136:                 break;
 137:             FI
 138:             /* falls through */
 139: 
 140:         default:
 141:         error:
 142:             errflg = (space&DSP ? BADDAT: BADTXT);
 143:             return(0);
 144:     }
 145:     return(1);
 146: }
 147: 
 148: setovmap(ovno)
 149: OVTAG ovno;
 150: {
 151:     REG MAPPTR amap;
 152: 
 153:     if ((!overlay) || (ovno < 0) || (ovno > 7))
 154:         return;
 155:     amap = &txtmap;
 156:     IF ovno == 0
 157:     THEN    amap->eo = amap->bo;
 158:         amap->fo = 0;
 159:     ELSE    amap->eo = amap->bo + ovlseg.ov[ovno-1];
 160:         amap->fo = ovloff[ovno-1];
 161:     FI
 162:     var[VARC] = curov = ovno;
 163:     if (pid)
 164:         choverlay(ovno);
 165: }
 166: 
 167: within(adr,lbd,ubd)
 168: L_INT   adr, lbd, ubd;
 169: {
 170:     return(adr>=lbd && adr<ubd);
 171: }

Defined functions

Defined variables