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1.1 root 1: #define lv yylval
2: #define v yyval
3:
4:
5: yylex()
6: {
7: register c;
8: register struct tab *tp;
9: extern TERMtype;
10:
11: if(nlexsym != -1) {
12: if (TERMtype == 1) dofix(); /* convert iline */
13: c = nlexsym;
14: nlexsym = -1;
15: return(c);
16:
17: }
18: while(litflag > 0) {
19: if (TERMtype == 0)c = (int)*iline++;
20: else c = asciich();
21: if(c == '\n') {
22: nlexsym = 0;
23: return(eol);
24: }
25: }
26: do
27: if (TERMtype == 0)c = (int)*iline++;
28: else c = asciich();
29: while(c == ' ');
30: if(c == '\n') {
31: nlexsym = 0;
32: return(eol);
33: }
34: if(alpha(c))
35: return(getnam(c));
36: if(digit(c) || c == '@' ||
37: (c=='.' && digit(*iline)))
38: return(getnum(c));
39: c &= 0377;
40: for(tp = tab; tp->input; tp++)
41: if(tp->input == c) {
42: lv = tp->lexval;
43: return(tp->retval);
44: }
45: return(unk);
46: }
47:
48: getnam(ic)
49: {
50: char name[NAMS];
51: register c;
52: register char *cp;
53: register struct nlist *np;
54:
55: cp = name;
56: do {
57: *cp++ = c;
58: if (TERMtype == 0)c = (int)*iline++;
59: else c = asciich();
60: } while(alpha(c) || digit(c));
61: *cp++ = 0;
62: iline--;
63: if(litflag < 0) { /* commands */
64: litflag = 0;
65: for(c=0; comtab[c]; c+=3)
66: if(equal(name, comtab[c]))
67: break;
68: lv = comtab[c+2];
69: return(comtab[c+1]);
70: }
71: if(a_label(name)){
72: return(numb);
73: }
74: for(np=nlist; np->namep; np++)
75: if(equal(np->namep, name)) {
76: lv = np;
77: switch(np->use) {
78:
79: case NF:
80: return(nfun);
81:
82: case MF:
83: return(mfun);
84:
85: case DF:
86: return(dfun);
87: }
88: return(nam);
89: }
90: np->namep = alloc(cp-name);
91: copy(CH, name, np->namep, cp-name);
92: np->type = LV;
93: lv = np;
94: return(nam);
95: }
96:
97: a_label(x)
98: register char *x;
99: {
100: register struct lablist *lblthru;
101:
102: lblthru = labldefs.nextll;
103: while(lblthru) {
104: if(equal(lblthru->lname,x)) {
105: datum = (double) lblthru->lno;
106: return(1);
107: }
108: lblthru = lblthru->nextll;
109: }
110: return(0);
111: }
112:
113: getnum(ic)
114: {
115: double d1, d2;
116: register c, n, n1;
117: int s, s1;
118:
119: s = 0;
120: n = 0;
121: d1 = 0.;
122: c = ic;
123: if(c == '@') {
124: s++;
125: if (TERMtype == 0)c = (int)*iline++;
126: else c = asciich();
127: }
128: while(digit(c)) {
129: d1 = d1*10. + c - '0';
130: if (TERMtype == 0)c = (int)*iline++;
131: else c = asciich();
132: }
133: if(c == '.') {
134: if (TERMtype == 0)c = (int)*iline++;
135: else c = asciich();
136: while(digit(c)) {
137: d1 = d1*10. + c - '0';
138: if (TERMtype == 0)c = (int)*iline++;
139: else c = asciich();
140: n--;
141: }
142: }
143: if(c == 'e') {
144: s1 = 0;
145: n1 = 0;
146: if (TERMtype == 0)c = (int)*iline++;
147: else c = asciich();
148: if(c == '@') {
149: s1++;
150: if (TERMtype == 0)c = (int)*iline++;
151: else c = asciich();
152: }
153: while(digit(c)) {
154: n1 = n1*10 + c - '0';
155: if (TERMtype == 0)c = (int)*iline++;
156: else c = asciich();
157: }
158: if(s1)
159: n -= n1; else
160: n += n1;
161: }
162: n1 = n;
163: if(n1 < 0)
164: n1 = -n1;
165: d2 = 1.;
166: while(n1--)
167: d2 *= 10.;
168: if(n < 0)
169: d1 /= d2; else
170: d1 *= d2;
171: if(s)
172: d1 = -d1;
173: iline--;
174: datum = d1;
175: return(numb);
176: }
177:
178: alpha(s)
179: {
180: register c;
181:
182: c = s & 0377;
183: if(c >= 'a' && c <= 'z')
184: return(1);
185: if(c == 'H')
186: return(1);
187: if(c == 'F')
188: return(1);
189: if(c >= 0220 && c<=0252)
190: return(1);
191: return(0);
192: }
193:
194: digit(s)
195: {
196: register c;
197:
198: c = s;
199: if(c >='0' && c <= '9')
200: return(1);
201: return(0);
202: }
203:
204: /*
205: * s is statement
206: * f is execution flag:
207: * 0 compile immediate
208: * 1 compile L
209: * 2 function definition
210: * 3 function prolog
211: * 4 function epilog
212: * 5 function body
213: */
214: int ilex[]
215: {
216: lex0, lex1, lex2, lex3, lex4, lex5, lex6
217: };
218: compile(s, f)
219: {
220: register char *p, *q;
221: char oline[OBJS];
222:
223: iline = s;
224: ccharp = oline;
225: litflag = 0;
226: nlexsym = ilex[f];
227: context = nlexsym;
228: if(yyparse()) {
229: pline(s, iline-s);
230: return(0);
231: }
232: *ccharp++ = EOF;
233: p = alloc(ccharp-oline);
234: iline = p;
235: for(q=oline; q<ccharp;)
236: *p++ = *q++;
237: return(iline);
238: }
239:
240: yyerror()
241: {
242: }
243:
244: name(np, c2)
245: {
246: register char *p;
247:
248: p = ccharp;
249: *ccharp++ = c2;
250: *ccharp++ = np.c[0];
251: *ccharp++ = np.c[1];
252: *ccharp++ = np.c[2];
253: *ccharp++ = np.c[3];
254: return(p);
255: }
256:
257: equal(a, b)
258: char *a, *b;
259: {
260: register char *c1, *c2;
261:
262: c1 = a;
263: c2 = b;
264: while(*c1++ == *c2)
265: if(*c2++ == 0)
266: return(1);
267: return(0);
268: }
269:
270: invert(a, b)
271: {
272:
273: flop(a, b);
274: flop(b, ccharp);
275: flop(a, ccharp);
276: }
277:
278: flop(a, b)
279: char *a, *b;
280: {
281: register char *a1, *a2;
282: register c;
283:
284: a1 = a;
285: a2 = b;
286: while(a1 < a2) {
287: c = *a1;
288: *a1++ = *--a2;
289: *a2 = c;
290: }
291: }
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