xref: /original-bsd/old/dbx/check.c (revision 23c6a147)
1 /*
2  * Copyright (c) 1983 The Regents of the University of California.
3  * All rights reserved.
4  *
5  * Redistribution and use in source and binary forms are permitted
6  * provided that the above copyright notice and this paragraph are
7  * duplicated in all such forms and that any documentation,
8  * advertising materials, and other materials related to such
9  * distribution and use acknowledge that the software was developed
10  * by the University of California, Berkeley.  The name of the
11  * University may not be used to endorse or promote products derived
12  * from this software without specific prior written permission.
13  * THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR
14  * IMPLIED WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED
15  * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE.
16  */
17 
18 #ifndef lint
19 static char sccsid[] = "@(#)check.c	5.3 (Berkeley) 05/23/89";
20 #endif /* not lint */
21 
22 /*
23  * Check a tree for semantic correctness.
24  */
25 
26 #include "defs.h"
27 #include "tree.h"
28 #include "operators.h"
29 #include "events.h"
30 #include "symbols.h"
31 #include "scanner.h"
32 #include "source.h"
33 #include "object.h"
34 #include "mappings.h"
35 #include "process.h"
36 #include <signal.h>
37 
38 #ifndef public
39 #endif
40 
41 /*
42  * Check that the nodes in a tree have the correct arguments
43  * in order to be evaluated.  Basically the error checking here
44  * frees the evaluation routines from worrying about anything
45  * except dynamic errors, e.g. subscript out of range.
46  */
47 
48 public check(p)
49 register Node p;
50 {
51     Node p1, p2;
52     Address addr;
53     Symbol f;
54 
55     checkref(p);
56     switch (p->op) {
57 	case O_ASSIGN:
58 	    p1 = p->value.arg[0];
59 	    p2 = p->value.arg[1];
60 	    if (varIsSet("$unsafeassign")) {
61 		if (size(p1->nodetype) != size(p2->nodetype)) {
62 		    error("incompatible sizes");
63 		}
64 	    } else if (not compatible(p1->nodetype, p2->nodetype)) {
65 		error("incompatible types");
66 	    }
67 	    break;
68 
69 	case O_CATCH:
70 	case O_IGNORE:
71 	    if (p->value.lcon < 0 or p->value.lcon > NSIG) {
72 		error("invalid signal number");
73 	    }
74 	    break;
75 
76 	case O_CONT:
77 	    if (p->value.lcon != DEFSIG and (
78 		p->value.lcon < 0 or p->value.lcon > NSIG)
79 	    ) {
80 		error("invalid signal number");
81 	    }
82 	    break;
83 
84 	case O_DUMP:
85 	    if (p->value.arg[0] != nil) {
86 		if (p->value.arg[0]->op == O_SYM) {
87 		    f = p->value.arg[0]->value.sym;
88 		    if (not isblock(f)) {
89 			error("\"%s\" is not a block", symname(f));
90 		    }
91 		} else {
92 		    beginerrmsg();
93 		    fprintf(stderr, "expected a symbol, found \"");
94 		    prtree(stderr, p->value.arg[0]);
95 		    fprintf(stderr, "\"");
96 		    enderrmsg();
97 		}
98 	    }
99 	    break;
100 
101 	case O_LIST:
102 	    if (p->value.arg[0]->op == O_SYM) {
103 		f = p->value.arg[0]->value.sym;
104 		if (not isblock(f) or ismodule(f)) {
105 		    error("\"%s\" is not a procedure or function", symname(f));
106 		}
107 		addr = firstline(f);
108 		if (addr == NOADDR) {
109 		    error("\"%s\" is empty", symname(f));
110 		}
111 	    }
112 	    break;
113 
114 	case O_TRACE:
115 	case O_TRACEI:
116 	    chktrace(p);
117 	    break;
118 
119 	case O_STOP:
120 	case O_STOPI:
121 	    chkstop(p);
122 	    break;
123 
124 	case O_CALLPROC:
125 	case O_CALL:
126 	    if (not isroutine(p->value.arg[0]->nodetype)) {
127 		beginerrmsg();
128 		fprintf(stderr, "\"");
129 		prtree(stderr, p->value.arg[0]);
130 		fprintf(stderr, "\" not call-able");
131 		enderrmsg();
132 	    }
133 	    break;
134 
135 	case O_WHEREIS:
136 	    if (p->value.arg[0]->op == O_SYM and
137 	      p->value.arg[0]->value.sym == nil) {
138 		error("symbol not defined");
139 	    }
140 	    break;
141 
142 	default:
143 	    break;
144     }
145 }
146 
147 /*
148  * Check arguments to a trace command.
149  */
150 
151 private chktrace(p)
152 Node p;
153 {
154     Node exp, place, cond;
155 
156     exp = p->value.arg[0];
157     place = p->value.arg[1];
158     cond = p->value.arg[2];
159     if (exp == nil) {
160 	chkblock(place);
161     } else if (exp->op == O_LCON or exp->op == O_QLINE) {
162 	if (place != nil) {
163 	    error("unexpected \"at\" or \"in\"");
164 	}
165 	if (p->op == O_TRACE) {
166 	    chkline(exp);
167 	} else {
168 	    chkaddr(exp);
169 	}
170     } else if (place != nil and (place->op == O_QLINE or place->op == O_LCON)) {
171 	if (p->op == O_TRACE) {
172 	    chkline(place);
173 	} else {
174 	    chkaddr(place);
175 	}
176     } else {
177 	if (exp->op != O_RVAL and exp->op != O_SYM and exp->op != O_CALL) {
178 	    error("can't trace expressions");
179 	}
180 	chkblock(place);
181     }
182 }
183 
184 /*
185  * Check arguments to a stop command.
186  */
187 
188 private chkstop(p)
189 Node p;
190 {
191     Node exp, place, cond;
192 
193     exp = p->value.arg[0];
194     place = p->value.arg[1];
195     cond = p->value.arg[2];
196     if (exp != nil) {
197 	if (exp->op != O_RVAL and exp->op != O_SYM and exp->op != O_LCON) {
198 	    beginerrmsg();
199 	    fprintf(stderr, "expected variable, found ");
200 	    prtree(stderr, exp);
201 	    enderrmsg();
202 	}
203 	chkblock(place);
204     } else if (place != nil) {
205 	if (place->op == O_SYM) {
206 	    chkblock(place);
207 	} else {
208 	    if (p->op == O_STOP) {
209 		chkline(place);
210 	    } else {
211 		chkaddr(place);
212 	    }
213 	}
214     }
215 }
216 
217 /*
218  * Check to see that the given node specifies some subprogram.
219  * Nil is ok since that means the entire program.
220  */
221 
222 private chkblock(b)
223 Node b;
224 {
225     Symbol p, outer;
226 
227     if (b != nil) {
228 	if (b->op != O_SYM) {
229 	    beginerrmsg();
230 	    fprintf(stderr, "expected subprogram, found ");
231 	    prtree(stderr, b);
232 	    enderrmsg();
233 	} else if (ismodule(b->value.sym)) {
234 	    outer = b->value.sym;
235 	    while (outer != nil) {
236 		find(p, outer->name) where p->block == outer endfind(p);
237 		if (p == nil) {
238 		    outer = nil;
239 		    error("\"%s\" is not a subprogram", symname(b->value.sym));
240 		} else if (ismodule(p)) {
241 		    outer = p;
242 		} else {
243 		    outer = nil;
244 		    b->value.sym = p;
245 		}
246 	    }
247 	} else if (
248 	    b->value.sym->class == VAR and
249 	    b->value.sym->name == b->value.sym->block->name and
250 	    b->value.sym->block->class == FUNC
251 	) {
252 	    b->value.sym = b->value.sym->block;
253 	} else if (not isblock(b->value.sym)) {
254 	    error("\"%s\" is not a subprogram", symname(b->value.sym));
255 	}
256     }
257 }
258 
259 /*
260  * Check to make sure a node corresponds to a source line.
261  */
262 
263 private chkline(p)
264 Node p;
265 {
266     if (p == nil) {
267 	error("missing line");
268     } else if (p->op != O_QLINE and p->op != O_LCON) {
269 	error("expected source line number, found \"%t\"", p);
270     }
271 }
272 
273 /*
274  * Check to make sure a node corresponds to an address.
275  */
276 
277 private chkaddr(p)
278 Node p;
279 {
280     if (p == nil) {
281 	error("missing address");
282     } else if (p->op != O_LCON and p->op != O_QLINE) {
283 	beginerrmsg();
284 	fprintf(stderr, "expected address, found \"");
285 	prtree(stderr, p);
286 	fprintf(stderr, "\"");
287 	enderrmsg();
288     }
289 }
290