1: # 2: /* 3: * 4: * UNIX debugger 5: * 6: */ 7: 8: #include "defs.h" 9: 10: 11: MSG BADSYM; 12: MSG BADVAR; 13: MSG BADKET; 14: MSG BADSYN; 15: MSG NOCFN; 16: MSG NOADR; 17: MSG BADLOC; 18: 19: SYMTAB symbol; 20: INT lastframe; 21: INT savlastf; 22: L_INT savframe; 23: INT savpc; 24: INT callpc; 25: 26: 27: 28: CHAR *lp; 29: INT octal; 30: STRING errflg; 31: L_INT localval; 32: CHAR isymbol[8]; 33: 34: CHAR lastc; 35: POS *endhdr; 36: 37: L_INT dot; 38: L_INT ditto; 39: INT dotinc; 40: L_INT var[]; 41: L_INT expv; 42: 43: 44: 45: 46: expr(a) 47: { /* term | term dyadic expr | */ 48: INT rc; 49: L_INT lhs; 50: 51: rdc(); lp--; rc=term(a); 52: 53: WHILE rc 54: DO lhs = expv; 55: 56: switch (readchar()) { 57: 58: case '+': 59: term(a|1); expv += lhs; break; 60: 61: case '-': 62: term(a|1); expv = lhs - expv; break; 63: 64: case '#': 65: term(a|1); expv = round(lhs,expv); break; 66: 67: case '*': 68: term(a|1); expv *= lhs; break; 69: 70: case '%': 71: term(a|1); expv = lhs/expv; break; 72: 73: case '&': 74: term(a|1); expv &= lhs; break; 75: 76: case '|': 77: term(a|1); expv |= lhs; break; 78: 79: case ')': 80: IF (a&2)==0 THEN error(BADKET); FI 81: 82: default: 83: lp--; 84: return(rc); 85: } 86: OD 87: return(rc); 88: } 89: 90: term(a) 91: { /* item | monadic item | (expr) | */ 92: 93: switch (readchar()) { 94: 95: case '*': 96: term(a|1); expv=chkget(expv,DSP); return(1); 97: 98: case '@': 99: term(a|1); expv=chkget(expv,ISP); return(1); 100: 101: case '-': 102: term(a|1); expv = -expv; return(1); 103: 104: case '~': 105: term(a|1); expv = ~expv; return(1); 106: 107: case '(': 108: expr(2); 109: IF *lp!=')' 110: THEN error(BADSYN); 111: ELSE lp++; return(1); 112: FI 113: 114: default: 115: lp--; 116: return(item(a)); 117: } 118: } 119: 120: item(a) 121: { /* name [ . local ] | number | . | ^ | <var | <register | 'x | | */ 122: INT base, d, frpt, regptr; 123: CHAR savc; 124: BOOL hex; 125: L_INT frame; 126: UNION{REAL r; L_INT i;} real; 127: SYMPTR symp; 128: 129: hex=FALSE; 130: 131: readchar(); 132: IF symchar(0) 133: THEN readsym(); 134: IF lastc=='.' 135: THEN frame=endhdr[r5]&EVEN; lastframe=0; callpc=endhdr[pc]; 136: WHILE errflg==0 137: DO savpc=callpc; 138: findroutine(frame); 139: IF eqsym(symbol.symc,isymbol,'~') 140: THEN break; 141: FI 142: lastframe=frame; 143: frame=get(frame,DSP)&EVEN; 144: IF frame==0 145: THEN error(NOCFN); 146: FI 147: OD 148: savlastf=lastframe; savframe=frame; 149: readchar(); 150: IF symchar(0) 151: THEN chkloc(expv=frame); 152: FI 153: ELIF (symp=lookupsym(isymbol))==0 THEN error(BADSYM); 154: ELSE expv = symp->symv; 155: FI 156: lp--; 157: 158: 159: ELIF digit(lastc) ORF (hex=TRUE, lastc=='#' ANDF hexdigit(readchar())) 160: THEN expv = 0; 161: base = (lastc == '0' ORF octal ? 8 : (hex ? 16 : 10)); 162: WHILE (hex ? hexdigit(lastc) : digit(lastc)) 163: DO expv *= base; 164: IF (d=convdig(lastc))>=base THEN error(BADSYN); FI 165: expv += d; readchar(); 166: IF expv==0 ANDF (lastc=='x' ORF lastc=='X') 167: THEN hex=TRUE; base=16; readchar(); 168: FI 169: OD 170: IF lastc=='.' ANDF (base==10 ORF expv==0) ANDF !hex 171: THEN real.r=expv; frpt=0; base=10; 172: WHILE digit(readchar()) 173: DO real.r *= base; frpt++; 174: real.r += lastc-'0'; 175: OD 176: WHILE frpt-- 177: DO real.r /= base; OD 178: expv = real.i; 179: FI 180: lp--; 181: 182: ELIF lastc=='.' 183: THEN readchar(); 184: IF symchar(0) 185: THEN lastframe=savlastf; callpc=savpc; findroutine(savframe); 186: chkloc(savframe); 187: ELSE expv=dot; 188: FI 189: lp--; 190: 191: ELIF lastc=='"' 192: THEN expv=ditto; 193: 194: ELIF lastc=='+' 195: THEN expv=inkdot(dotinc); 196: 197: ELIF lastc=='^' 198: THEN expv=inkdot(-dotinc); 199: 200: ELIF lastc=='<' 201: THEN savc=rdc(); 202: IF regptr=getreg(savc) 203: THEN expv=endhdr[regptr]; 204: ELIF (base=varchk(savc)) != -1 205: THEN expv=var[base]; 206: ELSE error(BADVAR); 207: FI 208: 209: ELIF lastc=='\'' 210: THEN d=4; expv=0; 211: WHILE quotchar() 212: DO IF d-- 213: THEN IF d==1 THEN expv =<<16; FI 214: expv |= ((d&1)?lastc:lastc<<8); 215: ELSE error(BADSYN); 216: FI 217: OD 218: 219: ELIF a 220: THEN error(NOADR); 221: ELSE lp--; return(0); 222: FI 223: return(1); 224: } 225: 226: /* service routines for expression reading */ 227: 228: readsym() 229: { 230: REG char *p; 231: 232: p = isymbol; 233: REP IF p < &isymbol[8] 234: THEN *p++ = lastc; 235: FI 236: readchar(); 237: PER symchar(1) DONE 238: WHILE p < &isymbol[8] DO *p++ = 0; OD 239: } 240: 241: SYMPTR lookupsym(symstr) 242: STRING symstr; 243: { 244: SYMPTR symp; 245: symset(); 246: WHILE (symp=symget()) 247: DO IF (symp->symf&SYMCHK)==symp->symf 248: ANDF eqsym(symp->symc, symstr,'_') 249: THEN return(symp); 250: FI 251: OD 252: return(0); 253: } 254: 255: hexdigit(c) 256: CHAR c; 257: { return((c>='0' ANDF c<='9') ORF (c>='a' ANDF c<='f')); 258: } 259: 260: convdig(c) 261: CHAR c; 262: { 263: IF digit(c) 264: THEN return(c-'0'); 265: ELIF hexdigit(c) 266: THEN return(c-'a'+10); 267: ELSE return(17); 268: FI 269: } 270: 271: digit(c) char c; {return(c>='0' ANDF c<='9');} 272: 273: letter(c) char c; {return(c>='a' ANDF c<='z' ORF c>='A' ANDF c<='Z');} 274: 275: symchar(dig) 276: { 277: IF lastc=='\\' THEN readchar(); return(TRUE); FI 278: return( letter(lastc) ORF lastc=='_' ORF dig ANDF digit(lastc) ); 279: } 280: 281: varchk(name) 282: { 283: IF digit(name) THEN return(name-'0'); FI 284: IF letter(name) THEN return((name&037)-1+10); FI 285: return(-1); 286: } 287: 288: chkloc(frame) 289: L_INT frame; 290: { 291: readsym(); 292: REP IF localsym(frame)==0 THEN error(BADLOC); FI 293: expv=localval; 294: PER !eqsym(symbol.symc,isymbol,'~') DONE 295: } 296: 297: eqsym(s1, s2, c) 298: REG STRING s1, s2; 299: CHAR c; 300: { 301: IF eqstr(s1,s2) 302: THEN return(TRUE); 303: ELIF *s1==c 304: THEN CHAR s3[8]; 305: REG INT i; 306: 307: s3[0]=c; 308: FOR i=1; i<8; i++ 309: DO s3[i] = *s2++; OD 310: 311: return(eqstr(s1,s3)); 312: FI 313: }
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