Commit | Line | Data |
---|---|---|
2a24676e DF |
1 | /* |
2 | * Copyright (c) 1983 Regents of the University of California. | |
3 | * All rights reserved. The Berkeley software License Agreement | |
4 | * specifies the terms and conditions for redistribution. | |
5 | */ | |
cccba246 | 6 | |
2a24676e | 7 | #ifndef lint |
34d5a416 | 8 | static char sccsid[] = "@(#)eval.c 5.5 (Berkeley) %G%"; |
2a24676e | 9 | #endif not lint |
0022c355 | 10 | |
34d5a416 | 11 | static char rcsid[] = "$Header: eval.c,v 1.2 87/03/25 19:48:33 donn Exp $"; |
cccba246 ML |
12 | |
13 | /* | |
14 | * Tree evaluation. | |
15 | */ | |
16 | ||
17 | #include "defs.h" | |
18 | #include "tree.h" | |
19 | #include "operators.h" | |
0022c355 | 20 | #include "debug.h" |
cccba246 ML |
21 | #include "eval.h" |
22 | #include "events.h" | |
23 | #include "symbols.h" | |
24 | #include "scanner.h" | |
25 | #include "source.h" | |
26 | #include "object.h" | |
27 | #include "mappings.h" | |
28 | #include "process.h" | |
2fd0f574 | 29 | #include "runtime.h" |
cccba246 ML |
30 | #include "machine.h" |
31 | #include <signal.h> | |
32 | ||
33 | #ifndef public | |
34 | ||
35 | #include "machine.h" | |
36 | ||
c760d7ed | 37 | #define STACKSIZE 20000 |
cccba246 ML |
38 | |
39 | typedef Char Stack; | |
40 | ||
41 | #define push(type, value) { \ | |
42 | ((type *) (sp += sizeof(type)))[-1] = (value); \ | |
43 | } | |
44 | ||
45 | #define pop(type) ( \ | |
46 | (*((type *) (sp -= sizeof(type)))) \ | |
47 | ) | |
48 | ||
2fd0f574 SL |
49 | #define popn(n, dest) { \ |
50 | sp -= n; \ | |
51 | bcopy(sp, dest, n); \ | |
52 | } | |
53 | ||
cccba246 ML |
54 | #define alignstack() { \ |
55 | sp = (Stack *) (( ((int) sp) + sizeof(int) - 1)&~(sizeof(int) - 1)); \ | |
56 | } | |
57 | ||
58 | #endif | |
59 | ||
60 | public Stack stack[STACKSIZE]; | |
61 | public Stack *sp = &stack[0]; | |
b5c2913a | 62 | public Boolean useInstLoc = false; |
cccba246 ML |
63 | |
64 | #define chksp() \ | |
65 | { \ | |
66 | if (sp < &stack[0]) { \ | |
67 | panic("stack underflow"); \ | |
68 | } \ | |
69 | } | |
70 | ||
71 | #define poparg(n, r, fr) { \ | |
72 | eval(p->value.arg[n]); \ | |
73 | if (isreal(p->op)) { \ | |
2fd0f574 SL |
74 | if (size(p->value.arg[n]->nodetype) == sizeof(float)) { \ |
75 | fr = pop(float); \ | |
76 | } else { \ | |
77 | fr = pop(double); \ | |
78 | } \ | |
cccba246 ML |
79 | } else if (isint(p->op)) { \ |
80 | r = popsmall(p->value.arg[n]->nodetype); \ | |
81 | } \ | |
82 | } | |
83 | ||
84 | #define Boolrep char /* underlying representation type for booleans */ | |
85 | ||
0022c355 ML |
86 | /* |
87 | * Command-level evaluation. | |
88 | */ | |
89 | ||
90 | public Node topnode; | |
91 | ||
92 | public topeval (p) | |
93 | Node p; | |
94 | { | |
95 | if (traceeval) { | |
96 | fprintf(stderr, "topeval("); | |
97 | prtree(stderr, p); | |
98 | fprintf(stderr, ")\n"); | |
99 | fflush(stderr); | |
100 | } | |
101 | topnode = p; | |
102 | eval(p); | |
103 | } | |
104 | ||
cccba246 ML |
105 | /* |
106 | * Evaluate a parse tree leaving the value on the top of the stack. | |
107 | */ | |
108 | ||
109 | public eval(p) | |
110 | register Node p; | |
111 | { | |
112 | long r0, r1; | |
113 | double fr0, fr1; | |
114 | Address addr; | |
115 | long i, n; | |
116 | int len; | |
0022c355 | 117 | Symbol s; |
cccba246 | 118 | Node n1, n2; |
0022c355 | 119 | boolean b; |
cccba246 | 120 | File file; |
0022c355 | 121 | String str; |
cccba246 ML |
122 | |
123 | checkref(p); | |
0022c355 ML |
124 | if (traceeval) { |
125 | fprintf(stderr, "begin eval %s\n", opname(p->op)); | |
c760d7ed | 126 | } |
cccba246 ML |
127 | switch (degree(p->op)) { |
128 | case BINARY: | |
129 | poparg(1, r1, fr1); | |
130 | poparg(0, r0, fr0); | |
131 | break; | |
132 | ||
133 | case UNARY: | |
134 | poparg(0, r0, fr0); | |
135 | break; | |
136 | ||
137 | default: | |
138 | /* do nothing */; | |
139 | } | |
140 | switch (p->op) { | |
141 | case O_SYM: | |
142 | s = p->value.sym; | |
143 | if (s == retaddrsym) { | |
144 | push(long, return_addr()); | |
0022c355 ML |
145 | } else if (isvariable(s)) { |
146 | if (s != program and not isactive(container(s))) { | |
147 | error("\"%s\" is not active", symname(s)); | |
148 | } | |
149 | if (isvarparam(s) and not isopenarray(s)) { | |
150 | rpush(address(s, nil), sizeof(Address)); | |
cccba246 | 151 | } else { |
0022c355 | 152 | push(Address, address(s, nil)); |
cccba246 | 153 | } |
0022c355 ML |
154 | } else if (isblock(s)) { |
155 | push(Symbol, s); | |
156 | } else if (isconst(s)) { | |
157 | eval(constval(s)); | |
158 | } else { | |
159 | error("can't evaluate a %s", classname(s)); | |
cccba246 ML |
160 | } |
161 | break; | |
162 | ||
163 | case O_LCON: | |
0022c355 | 164 | case O_CCON: |
cccba246 ML |
165 | r0 = p->value.lcon; |
166 | pushsmall(p->nodetype, r0); | |
167 | break; | |
168 | ||
169 | case O_FCON: | |
170 | push(double, p->value.fcon); | |
171 | break; | |
172 | ||
173 | case O_SCON: | |
174 | len = size(p->nodetype); | |
175 | mov(p->value.scon, sp, len); | |
176 | sp += len; | |
177 | break; | |
178 | ||
179 | case O_INDEX: | |
0022c355 ML |
180 | s = p->value.arg[0]->nodetype; |
181 | p->value.arg[0]->nodetype = t_addr; | |
182 | eval(p->value.arg[0]); | |
183 | p->value.arg[0]->nodetype = s; | |
184 | n = pop(Address); | |
185 | eval(p->value.arg[1]); | |
186 | evalindex(s, n, popsmall(p->value.arg[1]->nodetype)); | |
cccba246 ML |
187 | break; |
188 | ||
189 | case O_DOT: | |
190 | s = p->value.arg[1]->value.sym; | |
0022c355 ML |
191 | eval(p->value.arg[0]); |
192 | n = pop(long); | |
cccba246 ML |
193 | push(long, n + (s->symvalue.field.offset div 8)); |
194 | break; | |
195 | ||
196 | /* | |
197 | * Get the value of the expression addressed by the top of the stack. | |
198 | * Push the result back on the stack. | |
199 | */ | |
200 | ||
201 | case O_INDIR: | |
202 | case O_RVAL: | |
203 | addr = pop(long); | |
204 | if (addr == 0) { | |
205 | error("reference through nil pointer"); | |
206 | } | |
0022c355 | 207 | len = size(p->nodetype); |
cccba246 ML |
208 | rpush(addr, len); |
209 | break; | |
210 | ||
80ba8b01 | 211 | case O_TYPERENAME: |
34d5a416 | 212 | loophole(size(p->value.arg[0]->nodetype), size(p->nodetype)); |
80ba8b01 ML |
213 | break; |
214 | ||
cccba246 | 215 | case O_COMMA: |
0022c355 ML |
216 | eval(p->value.arg[0]); |
217 | if (p->value.arg[1] != nil) { | |
218 | eval(p->value.arg[1]); | |
219 | } | |
cccba246 ML |
220 | break; |
221 | ||
222 | case O_ITOF: | |
223 | push(double, (double) r0); | |
224 | break; | |
225 | ||
226 | case O_ADD: | |
227 | push(long, r0+r1); | |
228 | break; | |
229 | ||
230 | case O_ADDF: | |
231 | push(double, fr0+fr1); | |
232 | break; | |
233 | ||
234 | case O_SUB: | |
235 | push(long, r0-r1); | |
236 | break; | |
237 | ||
238 | case O_SUBF: | |
239 | push(double, fr0-fr1); | |
240 | break; | |
241 | ||
242 | case O_NEG: | |
243 | push(long, -r0); | |
244 | break; | |
245 | ||
246 | case O_NEGF: | |
247 | push(double, -fr0); | |
248 | break; | |
249 | ||
250 | case O_MUL: | |
251 | push(long, r0*r1); | |
252 | break; | |
253 | ||
254 | case O_MULF: | |
255 | push(double, fr0*fr1); | |
256 | break; | |
257 | ||
258 | case O_DIVF: | |
259 | if (fr1 == 0) { | |
260 | error("error: division by 0"); | |
261 | } | |
262 | push(double, fr0 / fr1); | |
263 | break; | |
264 | ||
265 | case O_DIV: | |
266 | if (r1 == 0) { | |
267 | error("error: div by 0"); | |
268 | } | |
269 | push(long, r0 div r1); | |
270 | break; | |
271 | ||
272 | case O_MOD: | |
273 | if (r1 == 0) { | |
274 | error("error: mod by 0"); | |
275 | } | |
276 | push(long, r0 mod r1); | |
277 | break; | |
278 | ||
279 | case O_LT: | |
280 | push(Boolrep, r0 < r1); | |
281 | break; | |
282 | ||
283 | case O_LTF: | |
284 | push(Boolrep, fr0 < fr1); | |
285 | break; | |
286 | ||
287 | case O_LE: | |
288 | push(Boolrep, r0 <= r1); | |
289 | break; | |
290 | ||
291 | case O_LEF: | |
292 | push(Boolrep, fr0 <= fr1); | |
293 | break; | |
294 | ||
295 | case O_GT: | |
296 | push(Boolrep, r0 > r1); | |
297 | break; | |
298 | ||
299 | case O_GTF: | |
300 | push(Boolrep, fr0 > fr1); | |
301 | break; | |
302 | ||
303 | case O_EQ: | |
304 | push(Boolrep, r0 == r1); | |
305 | break; | |
306 | ||
307 | case O_EQF: | |
308 | push(Boolrep, fr0 == fr1); | |
309 | break; | |
310 | ||
311 | case O_NE: | |
312 | push(Boolrep, r0 != r1); | |
313 | break; | |
314 | ||
315 | case O_NEF: | |
316 | push(Boolrep, fr0 != fr1); | |
317 | break; | |
318 | ||
319 | case O_AND: | |
320 | push(Boolrep, r0 and r1); | |
321 | break; | |
322 | ||
323 | case O_OR: | |
324 | push(Boolrep, r0 or r1); | |
325 | break; | |
326 | ||
327 | case O_ASSIGN: | |
328 | assign(p->value.arg[0], p->value.arg[1]); | |
329 | break; | |
330 | ||
331 | case O_CHFILE: | |
332 | if (p->value.scon == nil) { | |
333 | printf("%s\n", cursource); | |
334 | } else { | |
335 | file = opensource(p->value.scon); | |
336 | if (file == nil) { | |
337 | error("can't read \"%s\"", p->value.scon); | |
338 | } else { | |
339 | fclose(file); | |
340 | setsource(p->value.scon); | |
341 | } | |
342 | } | |
343 | break; | |
344 | ||
345 | case O_CONT: | |
fd49257b | 346 | cont(p->value.lcon); |
cccba246 ML |
347 | printnews(); |
348 | break; | |
349 | ||
350 | case O_LIST: | |
0022c355 | 351 | list(p); |
cccba246 ML |
352 | break; |
353 | ||
354 | case O_FUNC: | |
0022c355 | 355 | func(p->value.arg[0]); |
cccba246 ML |
356 | break; |
357 | ||
358 | case O_EXAMINE: | |
359 | eval(p->value.examine.beginaddr); | |
360 | r0 = pop(long); | |
361 | if (p->value.examine.endaddr == nil) { | |
362 | n = p->value.examine.count; | |
80ba8b01 ML |
363 | if (n == 0) { |
364 | printvalue(r0, p->value.examine.mode); | |
365 | } else if (streq(p->value.examine.mode, "i")) { | |
cccba246 ML |
366 | printninst(n, (Address) r0); |
367 | } else { | |
368 | printndata(n, (Address) r0, p->value.examine.mode); | |
369 | } | |
370 | } else { | |
371 | eval(p->value.examine.endaddr); | |
372 | r1 = pop(long); | |
373 | if (streq(p->value.examine.mode, "i")) { | |
374 | printinst((Address)r0, (Address)r1); | |
375 | } else { | |
376 | printdata((Address)r0, (Address)r1, p->value.examine.mode); | |
377 | } | |
378 | } | |
379 | break; | |
380 | ||
381 | case O_PRINT: | |
382 | for (n1 = p->value.arg[0]; n1 != nil; n1 = n1->value.arg[1]) { | |
383 | eval(n1->value.arg[0]); | |
384 | printval(n1->value.arg[0]->nodetype); | |
385 | putchar(' '); | |
386 | } | |
387 | putchar('\n'); | |
388 | break; | |
389 | ||
390 | case O_PSYM: | |
391 | if (p->value.arg[0]->op == O_SYM) { | |
392 | psym(p->value.arg[0]->value.sym); | |
393 | } else { | |
394 | psym(p->value.arg[0]->nodetype); | |
395 | } | |
396 | break; | |
397 | ||
398 | case O_QLINE: | |
399 | eval(p->value.arg[1]); | |
400 | break; | |
401 | ||
402 | case O_STEP: | |
403 | b = inst_tracing; | |
404 | inst_tracing = (Boolean) (not p->value.step.source); | |
405 | if (p->value.step.skipcalls) { | |
406 | next(); | |
407 | } else { | |
408 | stepc(); | |
409 | } | |
410 | inst_tracing = b; | |
b5c2913a | 411 | useInstLoc = (Boolean) (not p->value.step.source); |
cccba246 ML |
412 | printnews(); |
413 | break; | |
414 | ||
415 | case O_WHATIS: | |
416 | if (p->value.arg[0]->op == O_SYM) { | |
417 | printdecl(p->value.arg[0]->value.sym); | |
418 | } else { | |
419 | printdecl(p->value.arg[0]->nodetype); | |
420 | } | |
421 | break; | |
422 | ||
423 | case O_WHERE: | |
424 | wherecmd(); | |
425 | break; | |
426 | ||
427 | case O_WHEREIS: | |
c760d7ed | 428 | if (p->value.arg[0]->op == O_SYM) { |
0022c355 | 429 | printwhereis(stdout, p->value.arg[0]->value.sym); |
c760d7ed | 430 | } else { |
0022c355 | 431 | printwhereis(stdout, p->value.arg[0]->nodetype); |
c760d7ed | 432 | } |
cccba246 ML |
433 | break; |
434 | ||
435 | case O_WHICH: | |
c760d7ed | 436 | if (p->value.arg[0]->op == O_SYM) { |
0022c355 | 437 | printwhich(stdout, p->value.arg[0]->value.sym); |
c760d7ed | 438 | } else { |
0022c355 | 439 | printwhich(stdout, p->value.arg[0]->nodetype); |
c760d7ed | 440 | } |
cccba246 ML |
441 | putchar('\n'); |
442 | break; | |
443 | ||
444 | case O_ALIAS: | |
445 | n1 = p->value.arg[0]; | |
446 | n2 = p->value.arg[1]; | |
0022c355 ML |
447 | if (n2 == nil) { |
448 | if (n1 == nil) { | |
449 | alias(nil, nil, nil); | |
450 | } else { | |
451 | alias(n1->value.name, nil, nil); | |
452 | } | |
453 | } else if (n2->op == O_NAME) { | |
454 | str = ident(n2->value.name); | |
455 | alias(n1->value.name, nil, strdup(str)); | |
cccba246 | 456 | } else { |
0022c355 ML |
457 | if (n1->op == O_COMMA) { |
458 | alias( | |
459 | n1->value.arg[0]->value.name, | |
460 | (List) n1->value.arg[1], | |
461 | n2->value.scon | |
462 | ); | |
463 | } else { | |
464 | alias(n1->value.name, nil, n2->value.scon); | |
465 | } | |
cccba246 ML |
466 | } |
467 | break; | |
468 | ||
0022c355 ML |
469 | case O_UNALIAS: |
470 | unalias(p->value.arg[0]->value.name); | |
471 | break; | |
472 | ||
473 | case O_CALLPROC: | |
474 | callproc(p, false); | |
475 | break; | |
476 | ||
cccba246 | 477 | case O_CALL: |
0022c355 | 478 | callproc(p, true); |
cccba246 ML |
479 | break; |
480 | ||
481 | case O_CATCH: | |
0022c355 ML |
482 | if (p->value.lcon == 0) { |
483 | printsigscaught(process); | |
484 | } else { | |
485 | psigtrace(process, p->value.lcon, true); | |
486 | } | |
cccba246 ML |
487 | break; |
488 | ||
489 | case O_EDIT: | |
490 | edit(p->value.scon); | |
491 | break; | |
492 | ||
c760d7ed AF |
493 | case O_DEBUG: |
494 | debug(p); | |
495 | break; | |
496 | ||
2fd0f574 SL |
497 | case O_DOWN: |
498 | checkref(p->value.arg[0]); | |
499 | assert(p->value.arg[0]->op == O_LCON); | |
500 | down(p->value.arg[0]->value.lcon); | |
501 | break; | |
502 | ||
cccba246 | 503 | case O_DUMP: |
0022c355 ML |
504 | if (p->value.arg[0] == nil) { |
505 | dumpall(); | |
506 | } else { | |
507 | s = p->value.arg[0]->value.sym; | |
508 | if (s == curfunc) { | |
509 | dump(nil); | |
510 | } else { | |
511 | dump(s); | |
512 | } | |
513 | } | |
cccba246 ML |
514 | break; |
515 | ||
516 | case O_GRIPE: | |
517 | gripe(); | |
518 | break; | |
519 | ||
520 | case O_HELP: | |
521 | help(); | |
522 | break; | |
523 | ||
524 | case O_IGNORE: | |
0022c355 ML |
525 | if (p->value.lcon == 0) { |
526 | printsigsignored(process); | |
527 | } else { | |
528 | psigtrace(process, p->value.lcon, false); | |
529 | } | |
cccba246 ML |
530 | break; |
531 | ||
2fd0f574 SL |
532 | case O_RETURN: |
533 | if (p->value.arg[0] == nil) { | |
534 | rtnfunc(nil); | |
535 | } else { | |
536 | assert(p->value.arg[0]->op == O_SYM); | |
537 | rtnfunc(p->value.arg[0]->value.sym); | |
538 | } | |
539 | break; | |
540 | ||
cccba246 ML |
541 | case O_RUN: |
542 | run(); | |
543 | break; | |
544 | ||
0022c355 ML |
545 | case O_SET: |
546 | set(p->value.arg[0], p->value.arg[1]); | |
547 | break; | |
548 | ||
549 | case O_SEARCH: | |
550 | search(p->value.arg[0]->value.lcon, p->value.arg[1]->value.scon); | |
551 | break; | |
552 | ||
cccba246 ML |
553 | case O_SOURCE: |
554 | setinput(p->value.scon); | |
555 | break; | |
556 | ||
557 | case O_STATUS: | |
558 | status(); | |
559 | break; | |
560 | ||
561 | case O_TRACE: | |
562 | case O_TRACEI: | |
563 | trace(p); | |
cccba246 ML |
564 | break; |
565 | ||
566 | case O_STOP: | |
567 | case O_STOPI: | |
568 | stop(p); | |
cccba246 ML |
569 | break; |
570 | ||
0022c355 ML |
571 | case O_UNSET: |
572 | undefvar(p->value.arg[0]->value.name); | |
573 | break; | |
574 | ||
2fd0f574 SL |
575 | case O_UP: |
576 | checkref(p->value.arg[0]); | |
577 | assert(p->value.arg[0]->op == O_LCON); | |
578 | up(p->value.arg[0]->value.lcon); | |
579 | break; | |
580 | ||
cccba246 ML |
581 | case O_ADDEVENT: |
582 | addevent(p->value.event.cond, p->value.event.actions); | |
583 | break; | |
584 | ||
585 | case O_DELETE: | |
2fd0f574 SL |
586 | n1 = p->value.arg[0]; |
587 | while (n1->op == O_COMMA) { | |
588 | n2 = n1->value.arg[0]; | |
589 | assert(n2->op == O_LCON); | |
590 | if (not delevent((unsigned int) n2->value.lcon)) { | |
591 | error("unknown event %ld", n2->value.lcon); | |
592 | } | |
593 | n1 = n1->value.arg[1]; | |
594 | } | |
595 | assert(n1->op == O_LCON); | |
596 | if (not delevent((unsigned int) n1->value.lcon)) { | |
597 | error("unknown event %ld", n1->value.lcon); | |
598 | } | |
cccba246 ML |
599 | break; |
600 | ||
601 | case O_ENDX: | |
602 | endprogram(); | |
603 | break; | |
604 | ||
605 | case O_IF: | |
606 | if (cond(p->value.event.cond)) { | |
607 | evalcmdlist(p->value.event.actions); | |
608 | } | |
609 | break; | |
610 | ||
611 | case O_ONCE: | |
612 | event_once(p->value.event.cond, p->value.event.actions); | |
613 | break; | |
614 | ||
615 | case O_PRINTCALL: | |
616 | printcall(p->value.sym, whatblock(return_addr())); | |
617 | break; | |
618 | ||
619 | case O_PRINTIFCHANGED: | |
620 | printifchanged(p->value.arg[0]); | |
621 | break; | |
622 | ||
623 | case O_PRINTRTN: | |
624 | printrtn(p->value.sym); | |
625 | break; | |
626 | ||
627 | case O_PRINTSRCPOS: | |
628 | getsrcpos(); | |
629 | if (p->value.arg[0] == nil) { | |
630 | printsrcpos(); | |
631 | putchar('\n'); | |
632 | printlines(curline, curline); | |
633 | } else if (p->value.arg[0]->op == O_QLINE) { | |
634 | if (p->value.arg[0]->value.arg[1]->value.lcon == 0) { | |
635 | printf("tracei: "); | |
636 | printinst(pc, pc); | |
637 | } else { | |
0022c355 ML |
638 | if (canReadSource()) { |
639 | printf("trace: "); | |
640 | printlines(curline, curline); | |
641 | } | |
cccba246 ML |
642 | } |
643 | } else { | |
644 | printsrcpos(); | |
645 | printf(": "); | |
646 | eval(p->value.arg[0]); | |
647 | prtree(stdout, p->value.arg[0]); | |
648 | printf(" = "); | |
649 | printval(p->value.arg[0]->nodetype); | |
650 | putchar('\n'); | |
651 | } | |
652 | break; | |
653 | ||
654 | case O_PROCRTN: | |
655 | procreturn(p->value.sym); | |
656 | break; | |
657 | ||
658 | case O_STOPIFCHANGED: | |
659 | stopifchanged(p->value.arg[0]); | |
660 | break; | |
661 | ||
662 | case O_STOPX: | |
663 | isstopped = true; | |
664 | break; | |
665 | ||
666 | case O_TRACEON: | |
667 | traceon(p->value.trace.inst, p->value.trace.event, | |
668 | p->value.trace.actions); | |
669 | break; | |
670 | ||
671 | case O_TRACEOFF: | |
672 | traceoff(p->value.lcon); | |
673 | break; | |
674 | ||
675 | default: | |
676 | panic("eval: bad op %d", p->op); | |
677 | } | |
0022c355 ML |
678 | if (traceeval) { |
679 | fprintf(stderr, "end eval %s\n", opname(p->op)); | |
680 | } | |
cccba246 ML |
681 | } |
682 | ||
683 | /* | |
684 | * Evaluate a list of commands. | |
685 | */ | |
686 | ||
687 | public evalcmdlist(cl) | |
688 | Cmdlist cl; | |
689 | { | |
690 | Command c; | |
691 | ||
692 | foreach (Command, c, cl) | |
693 | evalcmd(c); | |
694 | endfor | |
695 | } | |
696 | ||
697 | /* | |
698 | * Push "len" bytes onto the expression stack from address "addr" | |
699 | * in the process. If there isn't room on the stack, print an error message. | |
700 | */ | |
701 | ||
702 | public rpush(addr, len) | |
703 | Address addr; | |
704 | int len; | |
705 | { | |
706 | if (not canpush(len)) { | |
707 | error("expression too large to evaluate"); | |
708 | } else { | |
709 | chksp(); | |
710 | dread(sp, addr, len); | |
711 | sp += len; | |
712 | } | |
713 | } | |
714 | ||
715 | /* | |
716 | * Check if the stack has n bytes available. | |
717 | */ | |
718 | ||
719 | public Boolean canpush(n) | |
720 | Integer n; | |
721 | { | |
722 | return (Boolean) (sp + n < &stack[STACKSIZE]); | |
723 | } | |
724 | ||
725 | /* | |
726 | * Push a small scalar of the given type onto the stack. | |
727 | */ | |
728 | ||
729 | public pushsmall(t, v) | |
730 | Symbol t; | |
731 | long v; | |
732 | { | |
733 | register Integer s; | |
734 | ||
735 | s = size(t); | |
736 | switch (s) { | |
737 | case sizeof(char): | |
738 | push(char, v); | |
739 | break; | |
740 | ||
741 | case sizeof(short): | |
742 | push(short, v); | |
743 | break; | |
744 | ||
745 | case sizeof(long): | |
746 | push(long, v); | |
747 | break; | |
748 | ||
749 | default: | |
750 | panic("bad size %d in popsmall", s); | |
751 | } | |
752 | } | |
753 | ||
754 | /* | |
755 | * Pop an item of the given type which is assumed to be no larger | |
756 | * than a long and return it expanded into a long. | |
757 | */ | |
758 | ||
759 | public long popsmall(t) | |
760 | Symbol t; | |
761 | { | |
0022c355 | 762 | register integer n; |
cccba246 ML |
763 | long r; |
764 | ||
0022c355 ML |
765 | n = size(t); |
766 | if (n == sizeof(char)) { | |
767 | if (t->class == RANGE and t->symvalue.rangev.lower >= 0) { | |
768 | r = (long) pop(unsigned char); | |
769 | } else { | |
cccba246 | 770 | r = (long) pop(char); |
0022c355 ML |
771 | } |
772 | } else if (n == sizeof(short)) { | |
773 | if (t->class == RANGE and t->symvalue.rangev.lower >= 0) { | |
774 | r = (long) pop(unsigned short); | |
775 | } else { | |
cccba246 | 776 | r = (long) pop(short); |
0022c355 ML |
777 | } |
778 | } else if (n == sizeof(long)) { | |
779 | r = pop(long); | |
780 | } else { | |
781 | error("[internal error: size %d in popsmall]", n); | |
cccba246 ML |
782 | } |
783 | return r; | |
784 | } | |
785 | ||
786 | /* | |
787 | * Evaluate a conditional expression. | |
788 | */ | |
789 | ||
790 | public Boolean cond(p) | |
791 | Node p; | |
792 | { | |
34d5a416 DS |
793 | Boolean b; |
794 | int i; | |
cccba246 ML |
795 | |
796 | if (p == nil) { | |
797 | b = true; | |
798 | } else { | |
799 | eval(p); | |
34d5a416 DS |
800 | i = pop(Boolrep); |
801 | b = (Boolean) i; | |
cccba246 ML |
802 | } |
803 | return b; | |
804 | } | |
805 | ||
806 | /* | |
807 | * Return the address corresponding to a given tree. | |
808 | */ | |
809 | ||
810 | public Address lval(p) | |
811 | Node p; | |
812 | { | |
813 | if (p->op == O_RVAL) { | |
814 | eval(p->value.arg[0]); | |
815 | } else { | |
816 | eval(p); | |
817 | } | |
818 | return (Address) (pop(long)); | |
819 | } | |
820 | ||
821 | /* | |
822 | * Process a trace command, translating into the appropriate events | |
823 | * and associated actions. | |
824 | */ | |
825 | ||
826 | public trace(p) | |
827 | Node p; | |
828 | { | |
829 | Node exp, place, cond; | |
830 | Node left; | |
831 | ||
832 | exp = p->value.arg[0]; | |
833 | place = p->value.arg[1]; | |
834 | cond = p->value.arg[2]; | |
835 | if (exp == nil) { | |
836 | traceall(p->op, place, cond); | |
ab538816 | 837 | } else if (exp->op == O_QLINE or exp->op == O_LCON) { |
cccba246 ML |
838 | traceinst(p->op, exp, cond); |
839 | } else if (place != nil and place->op == O_QLINE) { | |
840 | traceat(p->op, exp, place, cond); | |
841 | } else { | |
7bf092d9 ML |
842 | left = exp; |
843 | if (left->op == O_RVAL or left->op == O_CALL) { | |
844 | left = left->value.arg[0]; | |
845 | } | |
cccba246 ML |
846 | if (left->op == O_SYM and isblock(left->value.sym)) { |
847 | traceproc(p->op, left->value.sym, place, cond); | |
848 | } else { | |
849 | tracedata(p->op, exp, place, cond); | |
850 | } | |
851 | } | |
852 | } | |
853 | ||
854 | /* | |
855 | * Set a breakpoint that will turn on tracing. | |
856 | */ | |
857 | ||
858 | private traceall(op, place, cond) | |
859 | Operator op; | |
860 | Node place; | |
861 | Node cond; | |
862 | { | |
863 | Symbol s; | |
864 | Node event; | |
865 | Command action; | |
866 | ||
867 | if (place == nil) { | |
868 | s = program; | |
869 | } else { | |
870 | s = place->value.sym; | |
871 | } | |
872 | event = build(O_EQ, build(O_SYM, procsym), build(O_SYM, s)); | |
873 | action = build(O_PRINTSRCPOS, | |
874 | build(O_QLINE, nil, build(O_LCON, (op == O_TRACE) ? 1 : 0))); | |
875 | if (cond != nil) { | |
876 | action = build(O_IF, cond, buildcmdlist(action)); | |
877 | } | |
878 | action = build(O_TRACEON, (op == O_TRACEI), buildcmdlist(action)); | |
879 | action->value.trace.event = addevent(event, buildcmdlist(action)); | |
fd49257b ML |
880 | if (isstdin()) { |
881 | printevent(action->value.trace.event); | |
882 | } | |
cccba246 ML |
883 | } |
884 | ||
885 | /* | |
886 | * Set up the appropriate breakpoint for tracing an instruction. | |
887 | */ | |
888 | ||
889 | private traceinst(op, exp, cond) | |
890 | Operator op; | |
891 | Node exp; | |
892 | Node cond; | |
893 | { | |
ab538816 | 894 | Node event, wh; |
cccba246 | 895 | Command action; |
fd49257b | 896 | Event e; |
cccba246 | 897 | |
ab538816 | 898 | if (exp->op == O_LCON) { |
0022c355 | 899 | wh = build(O_QLINE, build(O_SCON, strdup(cursource)), exp); |
ab538816 ML |
900 | } else { |
901 | wh = exp; | |
902 | } | |
cccba246 | 903 | if (op == O_TRACEI) { |
ab538816 | 904 | event = build(O_EQ, build(O_SYM, pcsym), wh); |
cccba246 | 905 | } else { |
ab538816 | 906 | event = build(O_EQ, build(O_SYM, linesym), wh); |
cccba246 | 907 | } |
ab538816 | 908 | action = build(O_PRINTSRCPOS, wh); |
cccba246 ML |
909 | if (cond) { |
910 | action = build(O_IF, cond, buildcmdlist(action)); | |
911 | } | |
fd49257b ML |
912 | e = addevent(event, buildcmdlist(action)); |
913 | if (isstdin()) { | |
914 | printevent(e); | |
915 | } | |
cccba246 ML |
916 | } |
917 | ||
918 | /* | |
919 | * Set a breakpoint to print an expression at a given line or address. | |
920 | */ | |
921 | ||
922 | private traceat(op, exp, place, cond) | |
923 | Operator op; | |
924 | Node exp; | |
925 | Node place; | |
926 | Node cond; | |
927 | { | |
928 | Node event; | |
929 | Command action; | |
fd49257b | 930 | Event e; |
cccba246 ML |
931 | |
932 | if (op == O_TRACEI) { | |
933 | event = build(O_EQ, build(O_SYM, pcsym), place); | |
934 | } else { | |
935 | event = build(O_EQ, build(O_SYM, linesym), place); | |
936 | } | |
937 | action = build(O_PRINTSRCPOS, exp); | |
938 | if (cond != nil) { | |
939 | action = build(O_IF, cond, buildcmdlist(action)); | |
940 | } | |
fd49257b ML |
941 | e = addevent(event, buildcmdlist(action)); |
942 | if (isstdin()) { | |
943 | printevent(e); | |
944 | } | |
cccba246 ML |
945 | } |
946 | ||
947 | /* | |
948 | * Construct event for tracing a procedure. | |
949 | * | |
950 | * What we want here is | |
951 | * | |
952 | * when $proc = p do | |
953 | * if <condition> then | |
954 | * printcall; | |
955 | * once $pc = $retaddr do | |
956 | * printrtn; | |
957 | * end; | |
958 | * end if; | |
959 | * end; | |
960 | * | |
961 | * Note that "once" is like "when" except that the event | |
962 | * deletes itself as part of its associated action. | |
963 | */ | |
964 | ||
965 | private traceproc(op, p, place, cond) | |
966 | Operator op; | |
967 | Symbol p; | |
968 | Node place; | |
969 | Node cond; | |
970 | { | |
971 | Node event; | |
972 | Command action; | |
973 | Cmdlist actionlist; | |
fd49257b | 974 | Event e; |
cccba246 ML |
975 | |
976 | action = build(O_PRINTCALL, p); | |
977 | actionlist = list_alloc(); | |
978 | cmdlist_append(action, actionlist); | |
979 | event = build(O_EQ, build(O_SYM, pcsym), build(O_SYM, retaddrsym)); | |
980 | action = build(O_ONCE, event, buildcmdlist(build(O_PRINTRTN, p))); | |
981 | cmdlist_append(action, actionlist); | |
982 | if (cond != nil) { | |
983 | actionlist = buildcmdlist(build(O_IF, cond, actionlist)); | |
984 | } | |
985 | event = build(O_EQ, build(O_SYM, procsym), build(O_SYM, p)); | |
fd49257b ML |
986 | e = addevent(event, actionlist); |
987 | if (isstdin()) { | |
988 | printevent(e); | |
989 | } | |
cccba246 ML |
990 | } |
991 | ||
992 | /* | |
993 | * Set up breakpoint for tracing data. | |
994 | */ | |
995 | ||
996 | private tracedata(op, exp, place, cond) | |
997 | Operator op; | |
998 | Node exp; | |
999 | Node place; | |
1000 | Node cond; | |
1001 | { | |
1002 | Symbol p; | |
1003 | Node event; | |
1004 | Command action; | |
1005 | ||
34d5a416 DS |
1006 | if (size(exp->nodetype) > MAXTRSIZE) { |
1007 | error("expression too large to trace (limit is %d bytes)", MAXTRSIZE); | |
1008 | } | |
cccba246 ML |
1009 | p = (place == nil) ? tcontainer(exp) : place->value.sym; |
1010 | if (p == nil) { | |
1011 | p = program; | |
1012 | } | |
1013 | action = build(O_PRINTIFCHANGED, exp); | |
1014 | if (cond != nil) { | |
1015 | action = build(O_IF, cond, buildcmdlist(action)); | |
1016 | } | |
1017 | action = build(O_TRACEON, (op == O_TRACEI), buildcmdlist(action)); | |
1018 | event = build(O_EQ, build(O_SYM, procsym), build(O_SYM, p)); | |
1019 | action->value.trace.event = addevent(event, buildcmdlist(action)); | |
fd49257b ML |
1020 | if (isstdin()) { |
1021 | printevent(action->value.trace.event); | |
1022 | } | |
cccba246 ML |
1023 | } |
1024 | ||
1025 | /* | |
1026 | * Setting and unsetting of stops. | |
1027 | */ | |
1028 | ||
1029 | public stop(p) | |
1030 | Node p; | |
1031 | { | |
40ea9b88 | 1032 | Node exp, place, cond, t; |
cccba246 ML |
1033 | Symbol s; |
1034 | Command action; | |
fd49257b | 1035 | Event e; |
cccba246 ML |
1036 | |
1037 | exp = p->value.arg[0]; | |
1038 | place = p->value.arg[1]; | |
1039 | cond = p->value.arg[2]; | |
1040 | if (exp != nil) { | |
1041 | stopvar(p->op, exp, place, cond); | |
cccba246 | 1042 | } else { |
40ea9b88 ML |
1043 | action = build(O_STOPX); |
1044 | if (cond != nil) { | |
1045 | action = build(O_IF, cond, buildcmdlist(action)); | |
1046 | } | |
2fd0f574 SL |
1047 | if (place == nil or place->op == O_SYM) { |
1048 | if (place == nil) { | |
1049 | s = program; | |
1050 | } else { | |
1051 | s = place->value.sym; | |
1052 | } | |
40ea9b88 ML |
1053 | t = build(O_EQ, build(O_SYM, procsym), build(O_SYM, s)); |
1054 | if (cond != nil) { | |
1055 | action = build(O_TRACEON, (p->op == O_STOPI), | |
1056 | buildcmdlist(action)); | |
1057 | e = addevent(t, buildcmdlist(action)); | |
1058 | action->value.trace.event = e; | |
1059 | } else { | |
1060 | e = addevent(t, buildcmdlist(action)); | |
1061 | } | |
1062 | if (isstdin()) { | |
1063 | printevent(e); | |
1064 | } | |
1065 | } else { | |
1066 | stopinst(p->op, place, cond, action); | |
1067 | } | |
cccba246 ML |
1068 | } |
1069 | } | |
1070 | ||
40ea9b88 | 1071 | private stopinst(op, place, cond, action) |
cccba246 ML |
1072 | Operator op; |
1073 | Node place; | |
1074 | Node cond; | |
40ea9b88 | 1075 | Command action; |
cccba246 ML |
1076 | { |
1077 | Node event; | |
fd49257b | 1078 | Event e; |
cccba246 ML |
1079 | |
1080 | if (op == O_STOP) { | |
1081 | event = build(O_EQ, build(O_SYM, linesym), place); | |
1082 | } else { | |
1083 | event = build(O_EQ, build(O_SYM, pcsym), place); | |
1084 | } | |
40ea9b88 | 1085 | e = addevent(event, buildcmdlist(action)); |
fd49257b ML |
1086 | if (isstdin()) { |
1087 | printevent(e); | |
1088 | } | |
cccba246 ML |
1089 | } |
1090 | ||
1091 | /* | |
1092 | * Implement stopping on assignment to a variable by adding it to | |
1093 | * the variable list. | |
1094 | */ | |
1095 | ||
1096 | private stopvar(op, exp, place, cond) | |
1097 | Operator op; | |
1098 | Node exp; | |
1099 | Node place; | |
1100 | Node cond; | |
1101 | { | |
1102 | Symbol p; | |
1103 | Node event; | |
1104 | Command action; | |
1105 | ||
34d5a416 DS |
1106 | if (size(exp->nodetype) > MAXTRSIZE) { |
1107 | error("expression too large to trace (limit is %d bytes)", MAXTRSIZE); | |
1108 | } | |
af28d1f8 ML |
1109 | if (place == nil) { |
1110 | if (exp->op == O_LCON) { | |
1111 | p = program; | |
1112 | } else { | |
1113 | p = tcontainer(exp); | |
1114 | if (p == nil) { | |
1115 | p = program; | |
1116 | } | |
1117 | } | |
1118 | } else { | |
1119 | p = place->value.sym; | |
1120 | } | |
1121 | action = build(O_STOPIFCHANGED, exp); | |
1122 | if (cond != nil) { | |
1123 | action = build(O_IF, cond, buildcmdlist(action)); | |
cccba246 | 1124 | } |
cccba246 ML |
1125 | action = build(O_TRACEON, (op == O_STOPI), buildcmdlist(action)); |
1126 | event = build(O_EQ, build(O_SYM, procsym), build(O_SYM, p)); | |
1127 | action->value.trace.event = addevent(event, buildcmdlist(action)); | |
fd49257b ML |
1128 | if (isstdin()) { |
1129 | printevent(action->value.trace.event); | |
1130 | } | |
cccba246 ML |
1131 | } |
1132 | ||
1133 | /* | |
1134 | * Assign the value of an expression to a variable (or term). | |
1135 | */ | |
1136 | ||
1137 | public assign(var, exp) | |
1138 | Node var; | |
1139 | Node exp; | |
1140 | { | |
1141 | Address addr; | |
2fd0f574 | 1142 | integer varsize, expsize; |
cccba246 ML |
1143 | char cvalue; |
1144 | short svalue; | |
1145 | long lvalue; | |
2fd0f574 | 1146 | float fvalue; |
cccba246 | 1147 | |
0022c355 ML |
1148 | if (var->op == O_SYM and regnum(var->value.sym) != -1) { |
1149 | eval(exp); | |
1150 | setreg(regnum(var->value.sym), pop(Address)); | |
cccba246 | 1151 | } else { |
0022c355 ML |
1152 | addr = lval(var); |
1153 | varsize = size(var->nodetype); | |
1154 | expsize = size(exp->nodetype); | |
1155 | eval(exp); | |
1156 | if (varsize == sizeof(float) and expsize == sizeof(double)) { | |
1157 | fvalue = (float) pop(double); | |
1158 | dwrite(&fvalue, addr, sizeof(fvalue)); | |
1159 | } else { | |
1160 | if (varsize < sizeof(long)) { | |
1161 | lvalue = 0; | |
1162 | popn(expsize, &lvalue); | |
1163 | if (varsize == sizeof(char)) { | |
2fd0f574 SL |
1164 | cvalue = lvalue; |
1165 | dwrite(&cvalue, addr, sizeof(cvalue)); | |
0022c355 | 1166 | } else if (varsize == sizeof(short)) { |
2fd0f574 SL |
1167 | svalue = lvalue; |
1168 | dwrite(&svalue, addr, sizeof(svalue)); | |
0022c355 ML |
1169 | } else { |
1170 | error("[internal error: bad size %d in assign]", varsize); | |
1171 | } | |
1172 | } else { | |
1173 | if (expsize <= varsize) { | |
1174 | sp -= expsize; | |
1175 | dwrite(sp, addr, expsize); | |
1176 | } else { | |
1177 | sp -= expsize; | |
1178 | dwrite(sp, addr, varsize); | |
1179 | } | |
2fd0f574 | 1180 | } |
0022c355 ML |
1181 | } |
1182 | } | |
1183 | } | |
1184 | ||
1185 | /* | |
1186 | * Set a debugger variable. | |
1187 | */ | |
1188 | ||
1189 | private set (var, exp) | |
1190 | Node var, exp; | |
1191 | { | |
1192 | Symbol t; | |
1193 | ||
1194 | if (var == nil) { | |
1195 | defvar(nil, nil); | |
1196 | } else if (exp == nil) { | |
1197 | defvar(var->value.name, nil); | |
1198 | } else if (var->value.name == identname("$frame", true)) { | |
1199 | t = exp->nodetype; | |
1200 | if (not compatible(t, t_int) and not compatible(t, t_addr)) { | |
1201 | error("$frame must be an address"); | |
1202 | } | |
1203 | eval(exp); | |
1204 | getnewregs(pop(Address)); | |
1205 | } else { | |
1206 | defvar(var->value.name, unrval(exp)); | |
1207 | } | |
1208 | } | |
1209 | ||
1210 | /* | |
1211 | * Execute a list command. | |
1212 | */ | |
1213 | ||
1214 | private list (p) | |
1215 | Node p; | |
1216 | { | |
1217 | Symbol f; | |
1218 | Address addr; | |
1219 | Lineno line, l1, l2; | |
1220 | ||
1221 | if (p->value.arg[0]->op == O_SYM) { | |
1222 | f = p->value.arg[0]->value.sym; | |
1223 | addr = firstline(f); | |
1224 | if (addr == NOADDR) { | |
1225 | error("no source lines for \"%s\"", symname(f)); | |
1226 | } | |
1227 | setsource(srcfilename(addr)); | |
1228 | line = srcline(addr); | |
1229 | getsrcwindow(line, &l1, &l2); | |
1230 | } else { | |
1231 | eval(p->value.arg[0]); | |
1232 | l1 = (Lineno) (pop(long)); | |
1233 | eval(p->value.arg[1]); | |
1234 | l2 = (Lineno) (pop(long)); | |
1235 | } | |
1236 | printlines(l1, l2); | |
1237 | } | |
1238 | ||
1239 | /* | |
1240 | * Execute a func command. | |
1241 | */ | |
1242 | ||
1243 | private func (p) | |
1244 | Node p; | |
1245 | { | |
1246 | Symbol s, f; | |
1247 | Address addr; | |
1248 | ||
1249 | if (p == nil) { | |
1250 | printname(stdout, curfunc); | |
1251 | putchar('\n'); | |
1252 | } else { | |
1253 | s = p->value.sym; | |
1254 | if (isroutine(s)) { | |
1255 | setcurfunc(s); | |
2fd0f574 | 1256 | } else { |
0022c355 ML |
1257 | find(f, s->name) where isroutine(f) endfind(f); |
1258 | if (f == nil) { | |
1259 | error("%s is not a procedure or function", symname(s)); | |
2fd0f574 | 1260 | } |
0022c355 ML |
1261 | setcurfunc(f); |
1262 | } | |
1263 | addr = codeloc(curfunc); | |
1264 | if (addr != NOADDR) { | |
1265 | setsource(srcfilename(addr)); | |
1266 | cursrcline = srcline(addr); | |
2fd0f574 | 1267 | } |
cccba246 ML |
1268 | } |
1269 | } | |
1270 | ||
cccba246 | 1271 | /* |
0022c355 | 1272 | * Send a message to the current support person. |
cccba246 ML |
1273 | */ |
1274 | ||
1275 | public gripe() | |
1276 | { | |
1277 | typedef Operation(); | |
1278 | Operation *old; | |
af28d1f8 | 1279 | int pid, status; |
2fd0f574 SL |
1280 | extern int versionNumber; |
1281 | char subject[100]; | |
cccba246 | 1282 | |
34d5a416 DS |
1283 | # ifdef MAINTAINER |
1284 | puts("Type control-D to end your message. Be sure to include"); | |
1285 | puts("your name and the name of the file you are debugging."); | |
1286 | putchar('\n'); | |
1287 | old = signal(SIGINT, SIG_DFL); | |
1288 | sprintf(subject, "dbx (version 3.%d) gripe", versionNumber); | |
1289 | pid = back("Mail", stdin, stdout, "-s", subject, MAINTAINER, nil); | |
1290 | signal(SIGINT, SIG_IGN); | |
1291 | pwait(pid, &status); | |
1292 | signal(SIGINT, old); | |
1293 | if (status == 0) { | |
1294 | puts("Thank you."); | |
1295 | } else { | |
1296 | puts("\nMail not sent."); | |
1297 | } | |
1298 | # else | |
1299 | puts("Sorry, no dbx maintainer available to gripe to."); | |
1300 | puts("Try contacting your system manager."); | |
1301 | # endif | |
cccba246 ML |
1302 | } |
1303 | ||
1304 | /* | |
1305 | * Give the user some help. | |
1306 | */ | |
1307 | ||
1308 | public help() | |
1309 | { | |
1310 | puts("run - begin execution of the program"); | |
2fd0f574 SL |
1311 | puts("print <exp> - print the value of the expression"); |
1312 | puts("where - print currently active procedures"); | |
1313 | puts("stop at <line> - suspend execution at the line"); | |
1314 | puts("stop in <proc> - suspend execution when <proc> is called"); | |
cccba246 ML |
1315 | puts("cont - continue execution"); |
1316 | puts("step - single step one line"); | |
1317 | puts("next - step to next line (skip over calls)"); | |
1318 | puts("trace <line#> - trace execution of the line"); | |
1319 | puts("trace <proc> - trace calls to the procedure"); | |
1320 | puts("trace <var> - trace changes to the variable"); | |
1321 | puts("trace <exp> at <line#> - print <exp> when <line> is reached"); | |
cccba246 ML |
1322 | puts("status - print trace/stop's in effect"); |
1323 | puts("delete <number> - remove trace or stop of given number"); | |
2fd0f574 | 1324 | puts("call <proc> - call a procedure in program"); |
cccba246 ML |
1325 | puts("whatis <name> - print the declaration of the name"); |
1326 | puts("list <line>, <line> - list source lines"); | |
cccba246 ML |
1327 | puts("gripe - send mail to the person in charge of dbx"); |
1328 | puts("quit - exit dbx"); | |
1329 | } | |
1330 | ||
1331 | /* | |
1332 | * Divert output to the given file name. | |
1333 | * Cannot redirect to an existing file. | |
1334 | */ | |
1335 | ||
1336 | private int so_fd; | |
1337 | private Boolean notstdout; | |
1338 | ||
1339 | public setout(filename) | |
1340 | String filename; | |
1341 | { | |
1342 | File f; | |
1343 | ||
1344 | f = fopen(filename, "r"); | |
1345 | if (f != nil) { | |
1346 | fclose(f); | |
1347 | error("%s: file already exists", filename); | |
1348 | } else { | |
1349 | so_fd = dup(1); | |
1350 | close(1); | |
1351 | if (creat(filename, 0666) == nil) { | |
1352 | unsetout(); | |
1353 | error("can't create %s", filename); | |
1354 | } | |
1355 | notstdout = true; | |
1356 | } | |
1357 | } | |
1358 | ||
1359 | /* | |
1360 | * Revert output to standard output. | |
1361 | */ | |
1362 | ||
1363 | public unsetout() | |
1364 | { | |
1365 | fflush(stdout); | |
1366 | close(1); | |
1367 | if (dup(so_fd) != 1) { | |
1368 | panic("standard out dup failed"); | |
1369 | } | |
1370 | close(so_fd); | |
1371 | notstdout = false; | |
1372 | } | |
1373 | ||
1374 | /* | |
1375 | * Determine is standard output is currently being redirected | |
1376 | * to a file (as far as we know). | |
1377 | */ | |
1378 | ||
1379 | public Boolean isredirected() | |
1380 | { | |
1381 | return notstdout; | |
1382 | } |