1 |
#ifndef lint |
2 |
static const char RCSid[] = "$Id: caldefn.c,v 2.14 2003/03/10 17:13:29 greg Exp $"; |
3 |
#endif |
4 |
/* |
5 |
* Store variable definitions. |
6 |
* |
7 |
* 7/1/85 Greg Ward |
8 |
* |
9 |
* 11/11/85 Added conditional compiles (OUTCHAN) for control output. |
10 |
* |
11 |
* 4/2/86 Added conditional compiles for function definitions (FUNCTION). |
12 |
* |
13 |
* 1/15/88 Added clock for caching of variable values. |
14 |
* |
15 |
* 11/16/88 Added VARDEF structure for hard linking. |
16 |
* |
17 |
* 5/31/90 Added conditional compile (REDEFW) for redefinition warning. |
18 |
* |
19 |
* 4/23/91 Added ':' assignment for constant expressions |
20 |
* |
21 |
* 8/7/91 Added optional context path to append to variable names |
22 |
* |
23 |
* 5/17/2001 Fixed clock counter wrapping behavior |
24 |
* |
25 |
* 2/19/03 Eliminated conditional compiles in favor of esupport extern. |
26 |
*/ |
27 |
|
28 |
#include "copyright.h" |
29 |
|
30 |
#include <stdio.h> |
31 |
|
32 |
#include <string.h> |
33 |
|
34 |
#include <ctype.h> |
35 |
|
36 |
#include "calcomp.h" |
37 |
|
38 |
#ifndef NHASH |
39 |
#define NHASH 521 /* hash size (a prime!) */ |
40 |
#endif |
41 |
|
42 |
#define hash(s) (shash(s)%NHASH) |
43 |
|
44 |
#define newnode() (EPNODE *)ecalloc(1, sizeof(EPNODE)) |
45 |
|
46 |
static double dvalue(); |
47 |
|
48 |
#define MAXCLOCK (1L<<31) /* clock wrap value */ |
49 |
|
50 |
unsigned long eclock = 0; /* value storage timer */ |
51 |
|
52 |
#define MAXCNTX 1023 /* maximum context length */ |
53 |
|
54 |
static char context[MAXCNTX+1]; /* current context path */ |
55 |
|
56 |
static VARDEF *hashtbl[NHASH]; /* definition list */ |
57 |
static int htndx; /* index for */ |
58 |
static VARDEF *htpos; /* ...dfirst() and */ |
59 |
static EPNODE *ochpos; /* ...dnext */ |
60 |
static EPNODE *outchan; |
61 |
|
62 |
EPNODE *curfunc = NULL; |
63 |
#define dname(ep) ((ep)->v.kid->type == SYM ? \ |
64 |
(ep)->v.kid->v.name : \ |
65 |
(ep)->v.kid->v.kid->v.name) |
66 |
|
67 |
|
68 |
void |
69 |
fcompile(fname) /* get definitions from a file */ |
70 |
char *fname; |
71 |
{ |
72 |
FILE *fp; |
73 |
|
74 |
if (fname == NULL) |
75 |
fp = stdin; |
76 |
else if ((fp = fopen(fname, "r")) == NULL) { |
77 |
eputs(fname); |
78 |
eputs(": cannot open\n"); |
79 |
quit(1); |
80 |
} |
81 |
initfile(fp, fname, 0); |
82 |
while (nextc != EOF) |
83 |
getstatement(); |
84 |
if (fname != NULL) |
85 |
fclose(fp); |
86 |
} |
87 |
|
88 |
|
89 |
void |
90 |
scompile(str, fn, ln) /* get definitions from a string */ |
91 |
char *str; |
92 |
char *fn; |
93 |
int ln; |
94 |
{ |
95 |
initstr(str, fn, ln); |
96 |
while (nextc != EOF) |
97 |
getstatement(); |
98 |
} |
99 |
|
100 |
|
101 |
double |
102 |
varvalue(vname) /* return a variable's value */ |
103 |
char *vname; |
104 |
{ |
105 |
return(dvalue(vname, dlookup(vname))); |
106 |
} |
107 |
|
108 |
|
109 |
double |
110 |
evariable(ep) /* evaluate a variable */ |
111 |
EPNODE *ep; |
112 |
{ |
113 |
register VARDEF *dp = ep->v.ln; |
114 |
|
115 |
return(dvalue(dp->name, dp->def)); |
116 |
} |
117 |
|
118 |
|
119 |
void |
120 |
varset(vname, assign, val) /* set a variable's value */ |
121 |
char *vname; |
122 |
int assign; |
123 |
double val; |
124 |
{ |
125 |
char *qname; |
126 |
register EPNODE *ep1, *ep2; |
127 |
/* get qualified name */ |
128 |
qname = qualname(vname, 0); |
129 |
/* check for quick set */ |
130 |
if ((ep1 = dlookup(qname)) != NULL && ep1->v.kid->type == SYM) { |
131 |
ep2 = ep1->v.kid->sibling; |
132 |
if (ep2->type == NUM) { |
133 |
ep2->v.num = val; |
134 |
ep1->type = assign; |
135 |
return; |
136 |
} |
137 |
} |
138 |
/* hand build definition */ |
139 |
ep1 = newnode(); |
140 |
ep1->type = assign; |
141 |
ep2 = newnode(); |
142 |
ep2->type = SYM; |
143 |
ep2->v.name = savestr(vname); |
144 |
addekid(ep1, ep2); |
145 |
ep2 = newnode(); |
146 |
ep2->type = NUM; |
147 |
ep2->v.num = val; |
148 |
addekid(ep1, ep2); |
149 |
dremove(qname); |
150 |
dpush(qname, ep1); |
151 |
} |
152 |
|
153 |
|
154 |
void |
155 |
dclear(name) /* delete variable definitions of name */ |
156 |
char *name; |
157 |
{ |
158 |
register EPNODE *ep; |
159 |
|
160 |
while ((ep = dpop(name)) != NULL) { |
161 |
if (ep->type == ':') { |
162 |
dpush(name, ep); /* don't clear constants */ |
163 |
return; |
164 |
} |
165 |
epfree(ep); |
166 |
} |
167 |
} |
168 |
|
169 |
|
170 |
void |
171 |
dremove(name) /* delete all definitions of name */ |
172 |
char *name; |
173 |
{ |
174 |
register EPNODE *ep; |
175 |
|
176 |
while ((ep = dpop(name)) != NULL) |
177 |
epfree(ep); |
178 |
} |
179 |
|
180 |
|
181 |
int |
182 |
vardefined(name) /* return non-zero if variable defined */ |
183 |
char *name; |
184 |
{ |
185 |
register EPNODE *dp; |
186 |
|
187 |
return((dp = dlookup(name)) != NULL && dp->v.kid->type == SYM); |
188 |
} |
189 |
|
190 |
|
191 |
char * |
192 |
setcontext(ctx) /* set a new context path */ |
193 |
register char *ctx; |
194 |
{ |
195 |
register char *cpp; |
196 |
|
197 |
if (ctx == NULL) |
198 |
return(context); /* just asking */ |
199 |
while (*ctx == CNTXMARK) |
200 |
ctx++; /* skip past marks */ |
201 |
if (!*ctx) { |
202 |
context[0] = '\0'; /* empty means clear context */ |
203 |
return(context); |
204 |
} |
205 |
cpp = context; /* start context with mark */ |
206 |
*cpp++ = CNTXMARK; |
207 |
do { /* carefully copy new context */ |
208 |
if (cpp >= context+MAXCNTX) |
209 |
break; /* just copy what we can */ |
210 |
if (isid(*ctx)) |
211 |
*cpp++ = *ctx++; |
212 |
else { |
213 |
*cpp++ = '_'; ctx++; |
214 |
} |
215 |
} while (*ctx); |
216 |
while (cpp[-1] == CNTXMARK) /* cannot end in context mark */ |
217 |
cpp--; |
218 |
*cpp = '\0'; |
219 |
return(context); |
220 |
} |
221 |
|
222 |
|
223 |
char * |
224 |
pushcontext(ctx) /* push on another context */ |
225 |
char *ctx; |
226 |
{ |
227 |
char oldcontext[MAXCNTX+1]; |
228 |
register int n; |
229 |
|
230 |
strcpy(oldcontext, context); /* save old context */ |
231 |
setcontext(ctx); /* set new context */ |
232 |
n = strlen(context); /* tack on old */ |
233 |
if (n+strlen(oldcontext) > MAXCNTX) { |
234 |
strncpy(context+n, oldcontext, MAXCNTX-n); |
235 |
context[MAXCNTX] = '\0'; |
236 |
} else |
237 |
strcpy(context+n, oldcontext); |
238 |
return(context); |
239 |
} |
240 |
|
241 |
|
242 |
char * |
243 |
popcontext() /* pop off top context */ |
244 |
{ |
245 |
register char *cp1, *cp2; |
246 |
|
247 |
if (!context[0]) /* nothing left to pop */ |
248 |
return(context); |
249 |
cp2 = context; /* find mark */ |
250 |
while (*++cp2 && *cp2 != CNTXMARK) |
251 |
; |
252 |
cp1 = context; /* copy tail to front */ |
253 |
while (*cp1++ = *cp2++) |
254 |
; |
255 |
return(context); |
256 |
} |
257 |
|
258 |
|
259 |
char * |
260 |
qualname(nam, lvl) /* get qualified name */ |
261 |
register char *nam; |
262 |
int lvl; |
263 |
{ |
264 |
static char nambuf[MAXWORD+1]; |
265 |
register char *cp = nambuf, *cpp; |
266 |
/* check for explicit local */ |
267 |
if (*nam == CNTXMARK) |
268 |
if (lvl > 0) /* only action is to refuse search */ |
269 |
return(NULL); |
270 |
else |
271 |
nam++; |
272 |
else if (nam == nambuf) /* check for repeat call */ |
273 |
return(lvl > 0 ? NULL : nam); |
274 |
/* copy name to static buffer */ |
275 |
while (*nam) { |
276 |
if (cp >= nambuf+MAXWORD) |
277 |
goto toolong; |
278 |
*cp++ = *nam++; |
279 |
} |
280 |
/* check for explicit global */ |
281 |
if (cp > nambuf && cp[-1] == CNTXMARK) { |
282 |
if (lvl > 0) |
283 |
return(NULL); |
284 |
*--cp = '\0'; |
285 |
return(nambuf); /* already qualified */ |
286 |
} |
287 |
cpp = context; /* else skip the requested levels */ |
288 |
while (lvl-- > 0) { |
289 |
if (!*cpp) |
290 |
return(NULL); /* return NULL if past global level */ |
291 |
while (*++cpp && *cpp != CNTXMARK) |
292 |
; |
293 |
} |
294 |
while (*cpp) { /* copy context to static buffer */ |
295 |
if (cp >= nambuf+MAXWORD) |
296 |
goto toolong; |
297 |
*cp++ = *cpp++; |
298 |
} |
299 |
toolong: |
300 |
*cp = '\0'; |
301 |
return(nambuf); /* return qualified name */ |
302 |
} |
303 |
|
304 |
|
305 |
int |
306 |
incontext(qn) /* is qualified name in current context? */ |
307 |
register char *qn; |
308 |
{ |
309 |
if (!context[0]) /* global context accepts all */ |
310 |
return(1); |
311 |
while (*qn && *qn != CNTXMARK) /* find context mark */ |
312 |
qn++; |
313 |
return(!strcmp(qn, context)); |
314 |
} |
315 |
|
316 |
|
317 |
void |
318 |
chanout(cs) /* set output channels */ |
319 |
void (*cs)(); |
320 |
{ |
321 |
register EPNODE *ep; |
322 |
|
323 |
for (ep = outchan; ep != NULL; ep = ep->sibling) |
324 |
(*cs)(ep->v.kid->v.chan, evalue(ep->v.kid->sibling)); |
325 |
|
326 |
} |
327 |
|
328 |
|
329 |
void |
330 |
dcleanup(lvl) /* clear definitions (0->vars,1->output,2->consts) */ |
331 |
int lvl; |
332 |
{ |
333 |
register int i; |
334 |
register VARDEF *vp; |
335 |
register EPNODE *ep; |
336 |
/* if context is global, clear all */ |
337 |
for (i = 0; i < NHASH; i++) |
338 |
for (vp = hashtbl[i]; vp != NULL; vp = vp->next) |
339 |
if (incontext(vp->name)) |
340 |
if (lvl >= 2) |
341 |
dremove(vp->name); |
342 |
else |
343 |
dclear(vp->name); |
344 |
if (lvl >= 1) { |
345 |
for (ep = outchan; ep != NULL; ep = ep->sibling) |
346 |
epfree(ep); |
347 |
outchan = NULL; |
348 |
} |
349 |
} |
350 |
|
351 |
|
352 |
EPNODE * |
353 |
dlookup(name) /* look up a definition */ |
354 |
char *name; |
355 |
{ |
356 |
register VARDEF *vp; |
357 |
|
358 |
if ((vp = varlookup(name)) == NULL) |
359 |
return(NULL); |
360 |
return(vp->def); |
361 |
} |
362 |
|
363 |
|
364 |
VARDEF * |
365 |
varlookup(name) /* look up a variable */ |
366 |
char *name; |
367 |
{ |
368 |
int lvl = 0; |
369 |
register char *qname; |
370 |
register VARDEF *vp; |
371 |
/* find most qualified match */ |
372 |
while ((qname = qualname(name, lvl++)) != NULL) |
373 |
for (vp = hashtbl[hash(qname)]; vp != NULL; vp = vp->next) |
374 |
if (!strcmp(vp->name, qname)) |
375 |
return(vp); |
376 |
return(NULL); |
377 |
} |
378 |
|
379 |
|
380 |
VARDEF * |
381 |
varinsert(name) /* get a link to a variable */ |
382 |
char *name; |
383 |
{ |
384 |
register VARDEF *vp; |
385 |
int hv; |
386 |
|
387 |
if ((vp = varlookup(name)) != NULL) { |
388 |
vp->nlinks++; |
389 |
return(vp); |
390 |
} |
391 |
vp = (VARDEF *)emalloc(sizeof(VARDEF)); |
392 |
vp->lib = liblookup(name); |
393 |
if (vp->lib == NULL) /* if name not in library */ |
394 |
name = qualname(name, 0); /* use fully qualified version */ |
395 |
hv = hash(name); |
396 |
vp->name = savestr(name); |
397 |
vp->nlinks = 1; |
398 |
vp->def = NULL; |
399 |
vp->next = hashtbl[hv]; |
400 |
hashtbl[hv] = vp; |
401 |
return(vp); |
402 |
} |
403 |
|
404 |
|
405 |
void |
406 |
libupdate(fn) /* update library links */ |
407 |
char *fn; |
408 |
{ |
409 |
register int i; |
410 |
register VARDEF *vp; |
411 |
/* if fn is NULL then relink all */ |
412 |
for (i = 0; i < NHASH; i++) |
413 |
for (vp = hashtbl[i]; vp != NULL; vp = vp->next) |
414 |
if (vp->lib != NULL || fn == NULL || !strcmp(fn, vp->name)) |
415 |
vp->lib = liblookup(vp->name); |
416 |
} |
417 |
|
418 |
|
419 |
void |
420 |
varfree(ln) /* release link to variable */ |
421 |
register VARDEF *ln; |
422 |
{ |
423 |
register VARDEF *vp; |
424 |
int hv; |
425 |
|
426 |
if (--ln->nlinks > 0) |
427 |
return; /* still active */ |
428 |
|
429 |
hv = hash(ln->name); |
430 |
vp = hashtbl[hv]; |
431 |
if (vp == ln) |
432 |
hashtbl[hv] = vp->next; |
433 |
else { |
434 |
while (vp->next != ln) /* must be in list */ |
435 |
vp = vp->next; |
436 |
vp->next = ln->next; |
437 |
} |
438 |
freestr(ln->name); |
439 |
efree((char *)ln); |
440 |
} |
441 |
|
442 |
|
443 |
EPNODE * |
444 |
dfirst() /* return pointer to first definition */ |
445 |
{ |
446 |
htndx = 0; |
447 |
htpos = NULL; |
448 |
ochpos = outchan; |
449 |
return(dnext()); |
450 |
} |
451 |
|
452 |
|
453 |
EPNODE * |
454 |
dnext() /* return pointer to next definition */ |
455 |
{ |
456 |
register EPNODE *ep; |
457 |
register char *nm; |
458 |
|
459 |
while (htndx < NHASH) { |
460 |
if (htpos == NULL) |
461 |
htpos = hashtbl[htndx++]; |
462 |
while (htpos != NULL) { |
463 |
ep = htpos->def; |
464 |
nm = htpos->name; |
465 |
htpos = htpos->next; |
466 |
if (ep != NULL && incontext(nm)) |
467 |
return(ep); |
468 |
} |
469 |
} |
470 |
if ((ep = ochpos) != NULL) |
471 |
ochpos = ep->sibling; |
472 |
return(ep); |
473 |
} |
474 |
|
475 |
|
476 |
EPNODE * |
477 |
dpop(name) /* pop a definition */ |
478 |
char *name; |
479 |
{ |
480 |
register VARDEF *vp; |
481 |
register EPNODE *dp; |
482 |
|
483 |
if ((vp = varlookup(name)) == NULL || vp->def == NULL) |
484 |
return(NULL); |
485 |
dp = vp->def; |
486 |
vp->def = dp->sibling; |
487 |
varfree(vp); |
488 |
return(dp); |
489 |
} |
490 |
|
491 |
|
492 |
void |
493 |
dpush(nm, ep) /* push on a definition */ |
494 |
char *nm; |
495 |
register EPNODE *ep; |
496 |
{ |
497 |
register VARDEF *vp; |
498 |
|
499 |
vp = varinsert(nm); |
500 |
ep->sibling = vp->def; |
501 |
vp->def = ep; |
502 |
} |
503 |
|
504 |
|
505 |
void |
506 |
addchan(sp) /* add an output channel assignment */ |
507 |
EPNODE *sp; |
508 |
{ |
509 |
int ch = sp->v.kid->v.chan; |
510 |
register EPNODE *ep, *epl; |
511 |
|
512 |
for (epl = NULL, ep = outchan; ep != NULL; epl = ep, ep = ep->sibling) |
513 |
if (ep->v.kid->v.chan >= ch) { |
514 |
if (epl != NULL) |
515 |
epl->sibling = sp; |
516 |
else |
517 |
outchan = sp; |
518 |
if (ep->v.kid->v.chan > ch) |
519 |
sp->sibling = ep; |
520 |
else { |
521 |
sp->sibling = ep->sibling; |
522 |
epfree(ep); |
523 |
} |
524 |
return; |
525 |
} |
526 |
if (epl != NULL) |
527 |
epl->sibling = sp; |
528 |
else |
529 |
outchan = sp; |
530 |
sp->sibling = NULL; |
531 |
|
532 |
} |
533 |
|
534 |
|
535 |
void |
536 |
getstatement() /* get next statement */ |
537 |
{ |
538 |
register EPNODE *ep; |
539 |
char *qname; |
540 |
register VARDEF *vdef; |
541 |
|
542 |
if (nextc == ';') { /* empty statement */ |
543 |
scan(); |
544 |
return; |
545 |
} |
546 |
if (esupport&E_OUTCHAN && |
547 |
nextc == '$') { /* channel assignment */ |
548 |
ep = getchan(); |
549 |
addchan(ep); |
550 |
} else { /* ordinary definition */ |
551 |
ep = getdefn(); |
552 |
qname = qualname(dname(ep), 0); |
553 |
if (esupport&E_REDEFW && (vdef = varlookup(qname)) != NULL) |
554 |
if (vdef->def != NULL && epcmp(ep, vdef->def)) { |
555 |
wputs(qname); |
556 |
if (vdef->def->type == ':') |
557 |
wputs(": redefined constant expression\n"); |
558 |
else |
559 |
wputs(": redefined\n"); |
560 |
} else if (ep->v.kid->type == FUNC && vdef->lib != NULL) { |
561 |
wputs(qname); |
562 |
wputs(": definition hides library function\n"); |
563 |
} |
564 |
if (ep->type == ':') |
565 |
dremove(qname); |
566 |
else |
567 |
dclear(qname); |
568 |
dpush(qname, ep); |
569 |
} |
570 |
if (nextc != EOF) { |
571 |
if (nextc != ';') |
572 |
syntax("';' expected"); |
573 |
scan(); |
574 |
} |
575 |
} |
576 |
|
577 |
|
578 |
EPNODE * |
579 |
getdefn() /* A -> SYM = E1 */ |
580 |
/* SYM : E1 */ |
581 |
/* FUNC(SYM,..) = E1 */ |
582 |
/* FUNC(SYM,..) : E1 */ |
583 |
{ |
584 |
register EPNODE *ep1, *ep2; |
585 |
|
586 |
if (!isalpha(nextc) && nextc != CNTXMARK) |
587 |
syntax("illegal variable name"); |
588 |
|
589 |
ep1 = newnode(); |
590 |
ep1->type = SYM; |
591 |
ep1->v.name = savestr(getname()); |
592 |
|
593 |
if (esupport&E_FUNCTION && nextc == '(') { |
594 |
ep2 = newnode(); |
595 |
ep2->type = FUNC; |
596 |
addekid(ep2, ep1); |
597 |
ep1 = ep2; |
598 |
do { |
599 |
scan(); |
600 |
if (!isalpha(nextc)) |
601 |
syntax("illegal variable name"); |
602 |
ep2 = newnode(); |
603 |
ep2->type = SYM; |
604 |
ep2->v.name = savestr(getname()); |
605 |
addekid(ep1, ep2); |
606 |
} while (nextc == ','); |
607 |
if (nextc != ')') |
608 |
syntax("')' expected"); |
609 |
scan(); |
610 |
curfunc = ep1; |
611 |
} |
612 |
|
613 |
if (nextc != '=' && nextc != ':') |
614 |
syntax("'=' or ':' expected"); |
615 |
|
616 |
ep2 = newnode(); |
617 |
ep2->type = nextc; |
618 |
scan(); |
619 |
addekid(ep2, ep1); |
620 |
addekid(ep2, getE1()); |
621 |
|
622 |
if (ep1->type == SYM && ep1->sibling->type != NUM) { |
623 |
ep1 = newnode(); |
624 |
ep1->type = TICK; |
625 |
ep1->v.tick = 0; |
626 |
addekid(ep2, ep1); |
627 |
ep1 = newnode(); |
628 |
ep1->type = NUM; |
629 |
addekid(ep2, ep1); |
630 |
} |
631 |
curfunc = NULL; |
632 |
|
633 |
return(ep2); |
634 |
} |
635 |
|
636 |
|
637 |
EPNODE * |
638 |
getchan() /* A -> $N = E1 */ |
639 |
{ |
640 |
register EPNODE *ep1, *ep2; |
641 |
|
642 |
if (nextc != '$') |
643 |
syntax("missing '$'"); |
644 |
scan(); |
645 |
|
646 |
ep1 = newnode(); |
647 |
ep1->type = CHAN; |
648 |
ep1->v.chan = getinum(); |
649 |
|
650 |
if (nextc != '=') |
651 |
syntax("'=' expected"); |
652 |
scan(); |
653 |
|
654 |
ep2 = newnode(); |
655 |
ep2->type = '='; |
656 |
addekid(ep2, ep1); |
657 |
addekid(ep2, getE1()); |
658 |
|
659 |
return(ep2); |
660 |
} |
661 |
|
662 |
|
663 |
|
664 |
/* |
665 |
* The following routines are for internal use only: |
666 |
*/ |
667 |
|
668 |
|
669 |
static double |
670 |
dvalue(name, d) /* evaluate a variable */ |
671 |
char *name; |
672 |
EPNODE *d; |
673 |
{ |
674 |
register EPNODE *ep1, *ep2; |
675 |
|
676 |
if (d == NULL || d->v.kid->type != SYM) { |
677 |
eputs(name); |
678 |
eputs(": undefined variable\n"); |
679 |
quit(1); |
680 |
} |
681 |
ep1 = d->v.kid->sibling; /* get expression */ |
682 |
if (ep1->type == NUM) |
683 |
return(ep1->v.num); /* return if number */ |
684 |
ep2 = ep1->sibling; /* check time */ |
685 |
if (eclock >= MAXCLOCK) |
686 |
eclock = 1; /* wrap clock counter */ |
687 |
if (ep2->v.tick < MAXCLOCK && |
688 |
ep2->v.tick == 0 | ep2->v.tick != eclock) { |
689 |
ep2->v.tick = d->type == ':' ? MAXCLOCK : eclock; |
690 |
ep2 = ep2->sibling; |
691 |
ep2->v.num = evalue(ep1); /* needs new value */ |
692 |
} else |
693 |
ep2 = ep2->sibling; /* else reuse old value */ |
694 |
|
695 |
return(ep2->v.num); |
696 |
} |