1 |
#ifndef lint |
2 |
static const char RCSid[] = "$Id: calexpr.c,v 2.29 2004/03/28 20:33:12 schorsch Exp $"; |
3 |
#endif |
4 |
/* |
5 |
* Compute data values using expression parser |
6 |
* |
7 |
* 7/1/85 Greg Ward |
8 |
* |
9 |
* 11/11/85 Made channel input conditional with (INCHAN) compiles. |
10 |
* |
11 |
* 4/2/86 Added conditional compiles for function definitions (FUNCTION). |
12 |
* |
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* 1/29/87 Made variables conditional (VARIABLE) |
14 |
* |
15 |
* 5/19/88 Added constant subexpression elimination (RCONST) |
16 |
* |
17 |
* 2/19/03 Eliminated conditional compiles in favor of esupport extern. |
18 |
*/ |
19 |
|
20 |
#include "copyright.h" |
21 |
|
22 |
#include <stdio.h> |
23 |
#include <string.h> |
24 |
#include <ctype.h> |
25 |
#include <errno.h> |
26 |
#include <math.h> |
27 |
#include <stdlib.h> |
28 |
|
29 |
#include "rtmisc.h" |
30 |
#include "rtio.h" |
31 |
#include "rterror.h" |
32 |
#include "calcomp.h" |
33 |
|
34 |
#define MAXLINE 256 /* maximum line length */ |
35 |
|
36 |
#define newnode() (EPNODE *)ecalloc(1, sizeof(EPNODE)) |
37 |
|
38 |
#define isdecimal(c) (isdigit(c) || (c) == '.') |
39 |
|
40 |
static double euminus(EPNODE *), eargument(EPNODE *), enumber(EPNODE *); |
41 |
static double echannel(EPNODE *); |
42 |
static double eadd(EPNODE *), esubtr(EPNODE *), |
43 |
emult(EPNODE *), edivi(EPNODE *), |
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epow(EPNODE *); |
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static double ebotch(EPNODE *); |
46 |
|
47 |
unsigned int esupport = /* what to support */ |
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E_VARIABLE | E_FUNCTION ; |
49 |
|
50 |
int eofc = 0; /* optional end-of-file character */ |
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int nextc; /* lookahead character */ |
52 |
|
53 |
double (*eoper[])(EPNODE *) = { /* expression operations */ |
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ebotch, |
55 |
evariable, |
56 |
enumber, |
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euminus, |
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echannel, |
59 |
efunc, |
60 |
eargument, |
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ebotch, |
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ebotch, |
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0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0, |
64 |
0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0, |
65 |
emult, |
66 |
eadd, |
67 |
0, |
68 |
esubtr, |
69 |
0, |
70 |
edivi, |
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0,0,0,0,0,0,0,0,0,0, |
72 |
ebotch, |
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0,0, |
74 |
ebotch, |
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0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0, |
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0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0, |
77 |
epow, |
78 |
}; |
79 |
|
80 |
static FILE *infp; /* input file pointer */ |
81 |
static char *linbuf; /* line buffer */ |
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static char *infile; /* input file name */ |
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static int lineno; /* input line number */ |
84 |
static int linepos; /* position in buffer */ |
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|
86 |
|
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EPNODE * |
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eparse( /* parse an expression string */ |
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char *expr |
90 |
) |
91 |
{ |
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EPNODE *ep; |
93 |
|
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initstr(expr, NULL, 0); |
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curfunc = NULL; |
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ep = getE1(); |
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if (nextc != EOF) |
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syntax("unexpected character"); |
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return(ep); |
100 |
} |
101 |
|
102 |
|
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double |
104 |
eval( /* evaluate an expression string */ |
105 |
char *expr |
106 |
) |
107 |
{ |
108 |
register EPNODE *ep; |
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double rval; |
110 |
|
111 |
ep = eparse(expr); |
112 |
rval = evalue(ep); |
113 |
epfree(ep); |
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return(rval); |
115 |
} |
116 |
|
117 |
|
118 |
int |
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epcmp( /* compare two expressions for equivalence */ |
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register EPNODE *ep1, |
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register EPNODE *ep2 |
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) |
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{ |
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double d; |
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|
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if (ep1->type != ep2->type) |
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return(1); |
128 |
|
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switch (ep1->type) { |
130 |
|
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case VAR: |
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return(ep1->v.ln != ep2->v.ln); |
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|
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case NUM: |
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if (ep2->v.num == 0) |
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return(ep1->v.num != 0); |
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d = ep1->v.num / ep2->v.num; |
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return((d > 1.000000000001) | (d < 0.999999999999)); |
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|
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case CHAN: |
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case ARG: |
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return(ep1->v.chan != ep2->v.chan); |
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|
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case '=': |
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case ':': |
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return(epcmp(ep1->v.kid->sibling, ep2->v.kid->sibling)); |
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|
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case TICK: |
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case SYM: /* should never get this one */ |
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return(0); |
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|
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default: |
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ep1 = ep1->v.kid; |
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ep2 = ep2->v.kid; |
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while (ep1 != NULL) { |
156 |
if (ep2 == NULL) |
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return(1); |
158 |
if (epcmp(ep1, ep2)) |
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return(1); |
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ep1 = ep1->sibling; |
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ep2 = ep2->sibling; |
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} |
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return(ep2 != NULL); |
164 |
} |
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} |
166 |
|
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|
168 |
void |
169 |
epfree( /* free a parse tree */ |
170 |
register EPNODE *epar |
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) |
172 |
{ |
173 |
register EPNODE *ep; |
174 |
|
175 |
switch (epar->type) { |
176 |
|
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case VAR: |
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varfree(epar->v.ln); |
179 |
break; |
180 |
|
181 |
case SYM: |
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freestr(epar->v.name); |
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break; |
184 |
|
185 |
case NUM: |
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case CHAN: |
187 |
case ARG: |
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case TICK: |
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break; |
190 |
|
191 |
default: |
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while ((ep = epar->v.kid) != NULL) { |
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epar->v.kid = ep->sibling; |
194 |
epfree(ep); |
195 |
} |
196 |
break; |
197 |
|
198 |
} |
199 |
|
200 |
efree((char *)epar); |
201 |
} |
202 |
|
203 |
/* the following used to be a switch */ |
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static double |
205 |
eargument( |
206 |
EPNODE *ep |
207 |
) |
208 |
{ |
209 |
return(argument(ep->v.chan)); |
210 |
} |
211 |
|
212 |
static double |
213 |
enumber( |
214 |
EPNODE *ep |
215 |
) |
216 |
{ |
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return(ep->v.num); |
218 |
} |
219 |
|
220 |
static double |
221 |
euminus( |
222 |
EPNODE *ep |
223 |
) |
224 |
{ |
225 |
register EPNODE *ep1 = ep->v.kid; |
226 |
|
227 |
return(-evalue(ep1)); |
228 |
} |
229 |
|
230 |
static double |
231 |
echannel( |
232 |
EPNODE *ep |
233 |
) |
234 |
{ |
235 |
return(chanvalue(ep->v.chan)); |
236 |
} |
237 |
|
238 |
static double |
239 |
eadd( |
240 |
EPNODE *ep |
241 |
) |
242 |
{ |
243 |
register EPNODE *ep1 = ep->v.kid; |
244 |
|
245 |
return(evalue(ep1) + evalue(ep1->sibling)); |
246 |
} |
247 |
|
248 |
static double |
249 |
esubtr( |
250 |
EPNODE *ep |
251 |
) |
252 |
{ |
253 |
register EPNODE *ep1 = ep->v.kid; |
254 |
|
255 |
return(evalue(ep1) - evalue(ep1->sibling)); |
256 |
} |
257 |
|
258 |
static double |
259 |
emult( |
260 |
EPNODE *ep |
261 |
) |
262 |
{ |
263 |
register EPNODE *ep1 = ep->v.kid; |
264 |
|
265 |
return(evalue(ep1) * evalue(ep1->sibling)); |
266 |
} |
267 |
|
268 |
static double |
269 |
edivi( |
270 |
EPNODE *ep |
271 |
) |
272 |
{ |
273 |
register EPNODE *ep1 = ep->v.kid; |
274 |
double d; |
275 |
|
276 |
d = evalue(ep1->sibling); |
277 |
if (d == 0.0) { |
278 |
wputs("Division by zero\n"); |
279 |
errno = ERANGE; |
280 |
return(0.0); |
281 |
} |
282 |
return(evalue(ep1) / d); |
283 |
} |
284 |
|
285 |
static double |
286 |
epow( |
287 |
EPNODE *ep |
288 |
) |
289 |
{ |
290 |
register EPNODE *ep1 = ep->v.kid; |
291 |
double d; |
292 |
int lasterrno; |
293 |
|
294 |
lasterrno = errno; |
295 |
errno = 0; |
296 |
d = pow(evalue(ep1), evalue(ep1->sibling)); |
297 |
#ifdef IEEE |
298 |
if (!finite(d)) |
299 |
errno = EDOM; |
300 |
#endif |
301 |
if (errno == EDOM || errno == ERANGE) { |
302 |
wputs("Illegal power\n"); |
303 |
return(0.0); |
304 |
} |
305 |
errno = lasterrno; |
306 |
return(d); |
307 |
} |
308 |
|
309 |
static double |
310 |
ebotch( |
311 |
EPNODE *ep |
312 |
) |
313 |
{ |
314 |
eputs("Bad expression!\n"); |
315 |
quit(1); |
316 |
return 0.0; /* pro forma return */ |
317 |
} |
318 |
|
319 |
|
320 |
EPNODE * |
321 |
ekid( /* return pointer to a node's nth kid */ |
322 |
register EPNODE *ep, |
323 |
register int n |
324 |
) |
325 |
{ |
326 |
|
327 |
for (ep = ep->v.kid; ep != NULL; ep = ep->sibling) |
328 |
if (--n < 0) |
329 |
break; |
330 |
|
331 |
return(ep); |
332 |
} |
333 |
|
334 |
|
335 |
int |
336 |
nekids( /* return # of kids for node ep */ |
337 |
register EPNODE *ep |
338 |
) |
339 |
{ |
340 |
register int n = 0; |
341 |
|
342 |
for (ep = ep->v.kid; ep != NULL; ep = ep->sibling) |
343 |
n++; |
344 |
|
345 |
return(n); |
346 |
} |
347 |
|
348 |
|
349 |
void |
350 |
initfile( /* prepare input file */ |
351 |
FILE *fp, |
352 |
char *fn, |
353 |
int ln |
354 |
) |
355 |
{ |
356 |
static char inpbuf[MAXLINE]; |
357 |
|
358 |
infp = fp; |
359 |
linbuf = inpbuf; |
360 |
infile = fn; |
361 |
lineno = ln; |
362 |
linepos = 0; |
363 |
inpbuf[0] = '\0'; |
364 |
scan(); |
365 |
} |
366 |
|
367 |
|
368 |
void |
369 |
initstr( /* prepare input string */ |
370 |
char *s, |
371 |
char *fn, |
372 |
int ln |
373 |
) |
374 |
{ |
375 |
infp = NULL; |
376 |
infile = fn; |
377 |
lineno = ln; |
378 |
linbuf = s; |
379 |
linepos = 0; |
380 |
scan(); |
381 |
} |
382 |
|
383 |
|
384 |
void |
385 |
getscanpos( /* return current scan position */ |
386 |
char **fnp, |
387 |
int *lnp, |
388 |
char **spp, |
389 |
FILE **fpp |
390 |
) |
391 |
{ |
392 |
if (fnp != NULL) *fnp = infile; |
393 |
if (lnp != NULL) *lnp = lineno; |
394 |
if (spp != NULL) *spp = linbuf+linepos; |
395 |
if (fpp != NULL) *fpp = infp; |
396 |
} |
397 |
|
398 |
|
399 |
int |
400 |
scan(void) /* scan next character, return literal next */ |
401 |
{ |
402 |
register int lnext = 0; |
403 |
|
404 |
do { |
405 |
if (linbuf[linepos] == '\0') |
406 |
if (infp == NULL || fgets(linbuf, MAXLINE, infp) == NULL) |
407 |
nextc = EOF; |
408 |
else { |
409 |
nextc = linbuf[0]; |
410 |
lineno++; |
411 |
linepos = 1; |
412 |
} |
413 |
else |
414 |
nextc = linbuf[linepos++]; |
415 |
if (!lnext) |
416 |
lnext = nextc; |
417 |
if (nextc == eofc) { |
418 |
nextc = EOF; |
419 |
break; |
420 |
} |
421 |
if (nextc == '{') { |
422 |
scan(); |
423 |
while (nextc != '}') |
424 |
if (nextc == EOF) |
425 |
syntax("'}' expected"); |
426 |
else |
427 |
scan(); |
428 |
scan(); |
429 |
} |
430 |
} while (isspace(nextc)); |
431 |
return(lnext); |
432 |
} |
433 |
|
434 |
|
435 |
char * |
436 |
long2ascii( /* convert long to ascii */ |
437 |
long l |
438 |
) |
439 |
{ |
440 |
static char buf[16]; |
441 |
register char *cp; |
442 |
int neg = 0; |
443 |
|
444 |
if (l == 0) |
445 |
return("0"); |
446 |
if (l < 0) { |
447 |
l = -l; |
448 |
neg++; |
449 |
} |
450 |
cp = buf + sizeof(buf); |
451 |
*--cp = '\0'; |
452 |
while (l) { |
453 |
*--cp = l % 10 + '0'; |
454 |
l /= 10; |
455 |
} |
456 |
if (neg) |
457 |
*--cp = '-'; |
458 |
return(cp); |
459 |
} |
460 |
|
461 |
|
462 |
void |
463 |
syntax( /* report syntax error and quit */ |
464 |
char *err |
465 |
) |
466 |
{ |
467 |
register int i; |
468 |
|
469 |
if (infile != NULL || lineno != 0) { |
470 |
if (infile != NULL) eputs(infile); |
471 |
if (lineno != 0) { |
472 |
eputs(infile != NULL ? ", line " : "line "); |
473 |
eputs(long2ascii((long)lineno)); |
474 |
} |
475 |
eputs(":\n"); |
476 |
} |
477 |
eputs(linbuf); |
478 |
if (linbuf[strlen(linbuf)-1] != '\n') |
479 |
eputs("\n"); |
480 |
for (i = 0; i < linepos-1; i++) |
481 |
eputs(linbuf[i] == '\t' ? "\t" : " "); |
482 |
eputs("^ "); |
483 |
eputs(err); |
484 |
eputs("\n"); |
485 |
quit(1); |
486 |
} |
487 |
|
488 |
|
489 |
void |
490 |
addekid( /* add a child to ep */ |
491 |
register EPNODE *ep, |
492 |
EPNODE *ekid |
493 |
) |
494 |
{ |
495 |
if (ep->v.kid == NULL) |
496 |
ep->v.kid = ekid; |
497 |
else { |
498 |
for (ep = ep->v.kid; ep->sibling != NULL; ep = ep->sibling) |
499 |
; |
500 |
ep->sibling = ekid; |
501 |
} |
502 |
ekid->sibling = NULL; |
503 |
} |
504 |
|
505 |
|
506 |
char * |
507 |
getname(void) /* scan an identifier */ |
508 |
{ |
509 |
static char str[RMAXWORD+1]; |
510 |
register int i, lnext; |
511 |
|
512 |
lnext = nextc; |
513 |
for (i = 0; i < RMAXWORD && isid(lnext); i++, lnext = scan()) |
514 |
str[i] = lnext; |
515 |
str[i] = '\0'; |
516 |
while (isid(lnext)) /* skip rest of name */ |
517 |
lnext = scan(); |
518 |
|
519 |
return(str); |
520 |
} |
521 |
|
522 |
|
523 |
int |
524 |
getinum(void) /* scan a positive integer */ |
525 |
{ |
526 |
register int n, lnext; |
527 |
|
528 |
n = 0; |
529 |
lnext = nextc; |
530 |
while (isdigit(lnext)) { |
531 |
n = n * 10 + lnext - '0'; |
532 |
lnext = scan(); |
533 |
} |
534 |
return(n); |
535 |
} |
536 |
|
537 |
|
538 |
double |
539 |
getnum(void) /* scan a positive float */ |
540 |
{ |
541 |
register int i, lnext; |
542 |
char str[RMAXWORD+1]; |
543 |
|
544 |
i = 0; |
545 |
lnext = nextc; |
546 |
while (isdigit(lnext) && i < RMAXWORD) { |
547 |
str[i++] = lnext; |
548 |
lnext = scan(); |
549 |
} |
550 |
if (lnext == '.' && i < RMAXWORD) { |
551 |
str[i++] = lnext; |
552 |
lnext = scan(); |
553 |
if (i == 1 && !isdigit(lnext)) |
554 |
syntax("badly formed number"); |
555 |
while (isdigit(lnext) && i < RMAXWORD) { |
556 |
str[i++] = lnext; |
557 |
lnext = scan(); |
558 |
} |
559 |
} |
560 |
if ((lnext == 'e') | (lnext == 'E') && i < RMAXWORD) { |
561 |
str[i++] = lnext; |
562 |
lnext = scan(); |
563 |
if ((lnext == '-') | (lnext == '+') && i < RMAXWORD) { |
564 |
str[i++] = lnext; |
565 |
lnext = scan(); |
566 |
} |
567 |
if (!isdigit(lnext)) |
568 |
syntax("missing exponent"); |
569 |
while (isdigit(lnext) && i < RMAXWORD) { |
570 |
str[i++] = lnext; |
571 |
lnext = scan(); |
572 |
} |
573 |
} |
574 |
str[i] = '\0'; |
575 |
|
576 |
return(atof(str)); |
577 |
} |
578 |
|
579 |
|
580 |
EPNODE * |
581 |
getE1(void) /* E1 -> E1 ADDOP E2 */ |
582 |
/* E2 */ |
583 |
{ |
584 |
register EPNODE *ep1, *ep2; |
585 |
|
586 |
ep1 = getE2(); |
587 |
while (nextc == '+' || nextc == '-') { |
588 |
ep2 = newnode(); |
589 |
ep2->type = nextc; |
590 |
scan(); |
591 |
addekid(ep2, ep1); |
592 |
addekid(ep2, getE2()); |
593 |
if (esupport&E_RCONST && |
594 |
ep1->type == NUM && ep1->sibling->type == NUM) |
595 |
ep2 = rconst(ep2); |
596 |
ep1 = ep2; |
597 |
} |
598 |
return(ep1); |
599 |
} |
600 |
|
601 |
|
602 |
EPNODE * |
603 |
getE2(void) /* E2 -> E2 MULOP E3 */ |
604 |
/* E3 */ |
605 |
{ |
606 |
register EPNODE *ep1, *ep2; |
607 |
|
608 |
ep1 = getE3(); |
609 |
while (nextc == '*' || nextc == '/') { |
610 |
ep2 = newnode(); |
611 |
ep2->type = nextc; |
612 |
scan(); |
613 |
addekid(ep2, ep1); |
614 |
addekid(ep2, getE3()); |
615 |
if (esupport&E_RCONST && |
616 |
ep1->type == NUM && ep1->sibling->type == NUM) |
617 |
ep2 = rconst(ep2); |
618 |
ep1 = ep2; |
619 |
} |
620 |
return(ep1); |
621 |
} |
622 |
|
623 |
|
624 |
EPNODE * |
625 |
getE3(void) /* E3 -> E4 ^ E3 */ |
626 |
/* E4 */ |
627 |
{ |
628 |
register EPNODE *ep1, *ep2; |
629 |
|
630 |
ep1 = getE4(); |
631 |
if (nextc == '^') { |
632 |
ep2 = newnode(); |
633 |
ep2->type = nextc; |
634 |
scan(); |
635 |
addekid(ep2, ep1); |
636 |
addekid(ep2, getE3()); |
637 |
if (esupport&E_RCONST && |
638 |
ep1->type == NUM && ep1->sibling->type == NUM) |
639 |
ep2 = rconst(ep2); |
640 |
return(ep2); |
641 |
} |
642 |
return(ep1); |
643 |
} |
644 |
|
645 |
|
646 |
EPNODE * |
647 |
getE4(void) /* E4 -> ADDOP E5 */ |
648 |
/* E5 */ |
649 |
{ |
650 |
register EPNODE *ep1, *ep2; |
651 |
|
652 |
if (nextc == '-') { |
653 |
scan(); |
654 |
ep2 = getE5(); |
655 |
if (ep2->type == NUM) { |
656 |
ep2->v.num = -ep2->v.num; |
657 |
return(ep2); |
658 |
} |
659 |
if (ep2->type == UMINUS) { /* don't generate -(-E5) */ |
660 |
efree((char *)ep2); |
661 |
return(ep2->v.kid); |
662 |
} |
663 |
ep1 = newnode(); |
664 |
ep1->type = UMINUS; |
665 |
addekid(ep1, ep2); |
666 |
return(ep1); |
667 |
} |
668 |
if (nextc == '+') |
669 |
scan(); |
670 |
return(getE5()); |
671 |
} |
672 |
|
673 |
|
674 |
EPNODE * |
675 |
getE5(void) /* E5 -> (E1) */ |
676 |
/* VAR */ |
677 |
/* NUM */ |
678 |
/* $N */ |
679 |
/* FUNC(E1,..) */ |
680 |
/* ARG */ |
681 |
{ |
682 |
int i; |
683 |
char *nam; |
684 |
register EPNODE *ep1, *ep2; |
685 |
|
686 |
if (nextc == '(') { |
687 |
scan(); |
688 |
ep1 = getE1(); |
689 |
if (nextc != ')') |
690 |
syntax("')' expected"); |
691 |
scan(); |
692 |
return(ep1); |
693 |
} |
694 |
|
695 |
if (esupport&E_INCHAN && nextc == '$') { |
696 |
scan(); |
697 |
ep1 = newnode(); |
698 |
ep1->type = CHAN; |
699 |
ep1->v.chan = getinum(); |
700 |
return(ep1); |
701 |
} |
702 |
|
703 |
if (esupport&(E_VARIABLE|E_FUNCTION) && |
704 |
(isalpha(nextc) || nextc == CNTXMARK)) { |
705 |
nam = getname(); |
706 |
ep1 = NULL; |
707 |
if ((esupport&(E_VARIABLE|E_FUNCTION)) == (E_VARIABLE|E_FUNCTION) |
708 |
&& curfunc != NULL) |
709 |
for (i = 1, ep2 = curfunc->v.kid->sibling; |
710 |
ep2 != NULL; i++, ep2 = ep2->sibling) |
711 |
if (!strcmp(ep2->v.name, nam)) { |
712 |
ep1 = newnode(); |
713 |
ep1->type = ARG; |
714 |
ep1->v.chan = i; |
715 |
break; |
716 |
} |
717 |
if (ep1 == NULL) { |
718 |
ep1 = newnode(); |
719 |
ep1->type = VAR; |
720 |
ep1->v.ln = varinsert(nam); |
721 |
} |
722 |
if (esupport&E_FUNCTION && nextc == '(') { |
723 |
ep2 = newnode(); |
724 |
ep2->type = FUNC; |
725 |
addekid(ep2, ep1); |
726 |
ep1 = ep2; |
727 |
do { |
728 |
scan(); |
729 |
addekid(ep1, getE1()); |
730 |
} while (nextc == ','); |
731 |
if (nextc != ')') |
732 |
syntax("')' expected"); |
733 |
scan(); |
734 |
} else if (!(esupport&E_VARIABLE)) |
735 |
syntax("'(' expected"); |
736 |
if (esupport&E_RCONST && isconstvar(ep1)) |
737 |
ep1 = rconst(ep1); |
738 |
return(ep1); |
739 |
} |
740 |
|
741 |
if (isdecimal(nextc)) { |
742 |
ep1 = newnode(); |
743 |
ep1->type = NUM; |
744 |
ep1->v.num = getnum(); |
745 |
return(ep1); |
746 |
} |
747 |
syntax("unexpected character"); |
748 |
return NULL; /* pro forma return */ |
749 |
} |
750 |
|
751 |
|
752 |
EPNODE * |
753 |
rconst( /* reduce a constant expression */ |
754 |
register EPNODE *epar |
755 |
) |
756 |
{ |
757 |
register EPNODE *ep; |
758 |
|
759 |
ep = newnode(); |
760 |
ep->type = NUM; |
761 |
errno = 0; |
762 |
ep->v.num = evalue(epar); |
763 |
if (errno == EDOM || errno == ERANGE) |
764 |
syntax("bad constant expression"); |
765 |
epfree(epar); |
766 |
|
767 |
return(ep); |
768 |
} |
769 |
|
770 |
|
771 |
int |
772 |
isconstvar( /* is ep linked to a constant expression? */ |
773 |
register EPNODE *ep |
774 |
) |
775 |
{ |
776 |
register EPNODE *ep1; |
777 |
|
778 |
if (esupport&E_FUNCTION && ep->type == FUNC) { |
779 |
if (!isconstfun(ep->v.kid)) |
780 |
return(0); |
781 |
for (ep1 = ep->v.kid->sibling; ep1 != NULL; ep1 = ep1->sibling) |
782 |
if (ep1->type != NUM && !isconstfun(ep1)) |
783 |
return(0); |
784 |
return(1); |
785 |
} |
786 |
if (ep->type != VAR) |
787 |
return(0); |
788 |
ep1 = ep->v.ln->def; |
789 |
if (ep1 == NULL || ep1->type != ':') |
790 |
return(0); |
791 |
if (esupport&E_FUNCTION && ep1->v.kid->type != SYM) |
792 |
return(0); |
793 |
return(1); |
794 |
} |
795 |
|
796 |
|
797 |
int |
798 |
isconstfun( /* is ep linked to a constant function? */ |
799 |
register EPNODE *ep |
800 |
) |
801 |
{ |
802 |
register EPNODE *dp; |
803 |
register LIBR *lp; |
804 |
|
805 |
if (ep->type != VAR) |
806 |
return(0); |
807 |
if ((dp = ep->v.ln->def) != NULL) { |
808 |
if (dp->v.kid->type == FUNC) |
809 |
return(dp->type == ':'); |
810 |
else |
811 |
return(0); /* don't identify masked library functions */ |
812 |
} |
813 |
if ((lp = ep->v.ln->lib) != NULL) |
814 |
return(lp->atyp == ':'); |
815 |
return(0); |
816 |
} |