xref: /plan9-contrib/sys/src/cmd/grap/input.c (revision 219b2ee8daee37f4aad58d63f21287faa8e4ffdc)
1 #include <stdio.h>
2 #include <stdlib.h>
3 #include <string.h>
4 #include <ctype.h>
5 #include <errno.h>
6 #include "grap.h"
7 #include "y.tab.h"
8 
9 Infile	infile[10];
10 Infile	*curfile = infile;
11 
12 #define	MAXSRC	50
13 Src	src[MAXSRC];	/* input source stack */
14 Src	*srcp	= src;
15 
16 void pushsrc(int type, char *ptr)	/* new input source */
17 {
18 	if (++srcp >= src + MAXSRC)
19 		ERROR "inputs nested too deep" FATAL;
20 	srcp->type = type;
21 	srcp->sp = ptr;
22 	if (dbg) {
23 		printf("\n%3d ", srcp - src);
24 		switch (srcp->type) {
25 		case File:
26 			printf("push file\n", ((Infile *)ptr)->fname);
27 			break;
28 		case Macro:
29 			printf("push macro <%s>\n", ptr);
30 			break;
31 		case Char:
32 			printf("push char <%c>\n", *ptr);
33 			break;
34 		case Thru:
35 			printf("push thru\n");
36 			break;
37 		case String:
38 			printf("push string <%s>\n", ptr);
39 			break;
40 		case Free:
41 			printf("push free <%s>\n", ptr);
42 			break;
43 		default:
44 			ERROR "pushed bad type %d", srcp->type FATAL;
45 		}
46 	}
47 }
48 
49 void popsrc(void)	/* restore an old one */
50 {
51 	if (srcp <= src)
52 		ERROR "too many inputs popped" FATAL;
53 	if (dbg) {
54 		printf("%3d ", srcp - src);
55 		switch (srcp->type) {
56 		case File:
57 			printf("pop file\n");
58 			break;
59 		case Macro:
60 			printf("pop macro\n");
61 			break;
62 		case Char:
63 			printf("pop char <%c>\n", *srcp->sp);
64 			break;
65 		case Thru:
66 			printf("pop thru\n");
67 			break;
68 		case String:
69 			printf("pop string\n");
70 			break;
71 		case Free:
72 			printf("pop free\n");
73 			break;
74 		default:
75 			ERROR "pop weird input %d", srcp->type FATAL;
76 		}
77 	}
78 	srcp--;
79 }
80 
81 void definition(char *s)	/* collect definition for s and install */
82 				/* definitions picked up lexically */
83 {
84 	char *p;
85 	Obj *stp;
86 
87 	p = delimstr("definition");
88 	stp = lookup(s, 0);
89 	if (stp != NULL) {	/* it's there before */
90 		if (stp->type != DEFNAME) {
91 			ERROR "%s used as variable and definition", s WARNING;
92 			return;
93 		}
94 		free(stp->val);
95 	} else {
96 		stp = lookup(s, 1);
97 		stp->type = DEFNAME;
98 	}
99 	stp->val = p;
100 	dprintf("installing %s as `%s'\n", s, p);
101 }
102 
103 char *delimstr(char *s)	/* get body of X ... X */
104 			/* message if too big */
105 {
106 	int c, delim, rdelim, n, deep;
107 	static char *buf = NULL;
108 	static int nbuf = 0;
109 	char *p;
110 
111 	if (buf == NULL)
112 		buf = grow(buf, "buf", nbuf += 1000, sizeof(buf[0]));
113 	while ((delim = input()) == ' ' || delim == '\t' || delim == '\n')
114 		;
115 	rdelim = baldelim(delim, "{}");		/* could be "(){}[]`'" */
116 	deep = 1;
117 	for (p = buf; ; ) {
118 		c = input();
119 		if (c == rdelim)
120 			if (--deep == 0)
121 				break;
122 		if (c == delim)
123 			deep++;
124 		if (p >= buf + nbuf) {
125 			n = p - buf;
126 			buf = grow(buf, "buf", nbuf += 1000, sizeof(buf[0]));
127 			p = buf + n;
128 		}
129 		if (c == EOF)
130 			ERROR "end of file in %s %c %.20s... %c", s, delim, buf, delim FATAL;
131 		*p++ = c;
132 	}
133 	*p = '\0';
134 	dprintf("delimstr %s %c <%s> %c\n", s, delim, buf, delim);
135 	return tostring(buf);
136 }
137 
138 baldelim(int c, char *s)	/* replace c by balancing entry in s */
139 {
140 	for ( ; *s; s += 2)
141 		if (*s == c)
142 			return s[1];
143 	return c;
144 }
145 
146 Arg	args[10];	/* argument frames */
147 Arg	*argfp = args;	/* frame pointer */
148 int	argcnt;		/* number of arguments seen so far */
149 
150 void dodef(Obj *stp)	/* collect args and switch input to defn */
151 {
152 	int i, len;
153 	char *p;
154 	Arg *ap;
155 
156 	ap = argfp+1;
157 	if (ap >= args+10)
158 		ERROR "arguments too deep" FATAL;
159 	argcnt = 0;
160 	if (input() != '(')
161 		ERROR "disaster in dodef" FATAL;
162 	if (ap->argval == 0)
163 		ap->argval = malloc(1000);
164 	for (p = ap->argval; (len = getarg(p)) != -1; p += len) {
165 		ap->argstk[argcnt++] = p;
166 		if (input() == ')')
167 			break;
168 	}
169 	for (i = argcnt; i < MAXARGS; i++)
170 		ap->argstk[i] = "";
171 	if (dbg)
172 		for (i = 0; i < argcnt; i++)
173 			printf("arg %d.%d = <%s>\n", ap-args, i+1, ap->argstk[i]);
174 	argfp = ap;
175 	pushsrc(Macro, stp->val);
176 }
177 
178 getarg(char *p)	/* pick up single argument, store in p, return length */
179 {
180 	int n, c, npar;
181 
182 	n = npar = 0;
183 	for ( ;; ) {
184 		c = input();
185 		if (c == EOF)
186 			ERROR "end of file in getarg!" FATAL;
187 		if (npar == 0 && (c == ',' || c == ')'))
188 			break;
189 		if (c == '"')	/* copy quoted stuff intact */
190 			do {
191 				*p++ = c;
192 				n++;
193 			} while ((c = input()) != '"' && c != EOF);
194 		else if (c == '(')
195 			npar++;
196 		else if (c == ')')
197 			npar--;
198 		n++;
199 		*p++ = c;
200 	}
201 	*p = 0;
202 	unput(c);
203 	return(n + 1);
204 }
205 
206 #define	PBSIZE	2000
207 char	pbuf[PBSIZE];		/* pushback buffer */
208 char	*pb	= pbuf-1;	/* next pushed back character */
209 
210 char	ebuf[200];		/* collect input here for error reporting */
211 char	*ep	= ebuf;
212 
213 int	begin	= 0;
214 extern	int	thru;
215 extern	Obj	*thrudef;
216 extern	char	*untilstr;
217 
218 input(void)
219 {
220 	register int c;
221 
222 	if (thru && begin) {
223 		do_thru();
224 		begin = 0;
225 	}
226 	c = nextchar();
227 	dprintf(" <%c>", c);
228 	if (ep >= ebuf + sizeof ebuf)
229 		ep = ebuf;
230 	return *ep++ = c;
231 }
232 
233 nextchar(void)
234 {
235 	register int c;
236 
237   loop:
238 	switch (srcp->type) {
239 	case Free:	/* free string */
240 		free(srcp->sp);
241 		popsrc();
242 		goto loop;
243 	case Thru:	/* end of pushed back line */
244 		begin = 1;
245 		popsrc();
246 		c = '\n';
247 		break;
248 	case Char:
249 		if (pb >= pbuf) {
250 			c = *pb--;
251 			popsrc();
252 			break;
253 		} else {	/* can't happen? */
254 			popsrc();
255 			goto loop;
256 		}
257 	case String:
258 		c = *srcp->sp++;
259 		if (c == '\0') {
260 			popsrc();
261 			goto loop;
262 		} else {
263 			if (*srcp->sp == '\0')	/* empty, so pop */
264 				popsrc();
265 			break;
266 		}
267 	case Macro:
268 		c = *srcp->sp++;
269 		if (c == '\0') {
270 			if (--argfp < args)
271 				ERROR "argfp underflow" FATAL;
272 			popsrc();
273 			goto loop;
274 		} else if (c == '$' && isdigit(*srcp->sp)) {
275 			int n = 0;
276 			while (isdigit(*srcp->sp))
277 				n = 10 * n + *srcp->sp++ - '0';
278 			if (n > 0 && n <= MAXARGS)
279 				pushsrc(String, argfp->argstk[n-1]);
280 			goto loop;
281 		}
282 		break;
283 	case File:
284 		c = getc(curfile->fin);
285 		if (c == EOF) {
286 			if (curfile == infile)
287 				ERROR "end of file inside .G1/.G2" FATAL;
288 			if (curfile->fin != stdin) {
289 				fclose(curfile->fin);
290 				free(curfile->fname);	/* assumes allocated */
291 			}
292 			curfile--;
293 			printf(".lf %d %s\n", curfile->lineno, curfile->fname);
294 			popsrc();
295 			thru = 0;	/* chicken out */
296 			thrudef = 0;
297 			if (untilstr) {
298 				free(untilstr);
299 				untilstr = 0;
300 			}
301 			goto loop;
302 		}
303 		if (c == '\n')
304 			curfile->lineno++;
305 		break;
306 	}
307 	return c;
308 }
309 
310 void do_thru(void)	/* read one line, make into a macro expansion */
311 {
312 	int c, i;
313 	char *p;
314 	Arg *ap;
315 
316 	ap = argfp+1;
317 	if (ap >= args+10)
318 		ERROR "arguments too deep" FATAL;
319 	if (ap->argval == NULL)
320 		ap->argval = malloc(1000);
321 	p = ap->argval;
322 	argcnt = 0;
323 	c = nextchar();
324 	if (thru == 0) {	/* end of file was seen, so thru is done */
325 		unput(c);
326 		return;
327 	}
328 	for ( ; c != '\n' && c != EOF; ) {
329 		if (c == ' ' || c == '\t') {
330 			c = nextchar();
331 			continue;
332 		}
333 		if (argcnt >= MAXARGS)
334 			ERROR "too many fields on input line" FATAL;
335 		ap->argstk[argcnt++] = p;
336 		if (c == '"') {
337 			do {
338 				*p++ = c;
339 				if ((c = nextchar()) == '\\') {
340 					*p++ = c;
341 					*p++ = nextchar();
342 					c = nextchar();
343 				}
344 			} while (c != '"' && c != '\n' && c != EOF);
345 			*p++ = '"';
346 			if (c == '"')
347 				c = nextchar();
348 		} else {
349 			do {
350 				*p++ = c;
351 			} while ((c = nextchar())!=' ' && c!='\t' && c!='\n' && c!=',' && c!=EOF);
352 			if (c == ',')
353 				c = nextchar();
354 		}
355 		*p++ = '\0';
356 	}
357 	if (c == EOF)
358 		ERROR "unexpected end of file in do_thru" FATAL;
359 	if (argcnt == 0) {	/* ignore blank line */
360 		pushsrc(Thru, (char *) 0);
361 		return;
362 	}
363 	for (i = argcnt; i < MAXARGS; i++)
364 		ap->argstk[i] = "";
365 	if (dbg)
366 		for (i = 0; i < argcnt; i++)
367 			printf("arg %d.%d = <%s>\n", ap-args, i+1, ap->argstk[i]);
368 	if (strcmp(ap->argstk[0], ".G2") == 0) {
369 		thru = 0;
370 		thrudef = 0;
371 		pushsrc(String, "\n.G2\n");
372 		return;
373 	}
374 	if (untilstr && strcmp(ap->argstk[0], untilstr) == 0) {
375 		thru = 0;
376 		thrudef = 0;
377 		free(untilstr);
378 		untilstr = 0;
379 		return;
380 	}
381 	pushsrc(Thru, (char *) 0);
382 	dprintf("do_thru pushing back <%s>\n", thrudef->val);
383 	argfp = ap;
384 	pushsrc(Macro, thrudef->val);
385 }
386 
387 unput(int c)
388 {
389 	if (++pb >= pbuf + sizeof pbuf)
390 		ERROR "pushback overflow" FATAL;
391 	if (--ep < ebuf)
392 		ep = ebuf + sizeof(ebuf) - 1;
393 	*pb = c;
394 	pushsrc(Char, pb);
395 	return c;
396 }
397 
398 void pbstr(char *s)
399 {
400 	pushsrc(String, s);
401 }
402 
403 double errcheck(double x, char *s)
404 {
405 	extern int errno;
406 
407 	if (errno == EDOM) {
408 		errno = 0;
409 		ERROR "%s argument out of domain", s WARNING;
410 	} else if (errno == ERANGE) {
411 		errno = 0;
412 		ERROR "%s result out of range", s WARNING;
413 	}
414 	return x;
415 }
416 
417 char	errbuf[200];
418 
419 void yyerror(char *s)
420 {
421 	extern char *cmdname;
422 
423 	if (synerr)
424 		return;
425 	fflush(stdout);
426 	fprintf(stderr, "%s: %s", cmdname, s);
427 	if (errno > 0)
428 		perror("???");
429 	fprintf(stderr, " near line %d, file %s\n",
430 		curfile->lineno, curfile->fname);
431 	eprint();
432 	synerr = 1;
433 	errno = 0;
434 }
435 
436 void eprint(void)	/* try to print context around error */
437 {
438 	char *p, *q;
439 
440 	p = ep - 1;
441 	if (p > ebuf && *p == '\n')
442 		p--;
443 	for ( ; p >= ebuf && *p != '\n'; p--)
444 		;
445 	while (*p == '\n')
446 		p++;
447 	fprintf(stderr, " context is\n\t");
448 	for (q=ep-1; q>=p && *q!=' ' && *q!='\t' && *q!='\n'; q--)
449 		;
450 	while (p < q)
451 		putc(*p++, stderr);
452 	fprintf(stderr, " >>> ");
453 	while (p < ep)
454 		putc(*p++, stderr);
455 	fprintf(stderr, " <<< ");
456 	while (pb >= pbuf)
457 		putc(*pb--, stderr);
458 	fgets(ebuf, sizeof ebuf, curfile->fin);
459 	fprintf(stderr, "%s", ebuf);
460 	pbstr("\n.G2\n");	/* safety first */
461 	ep = ebuf;
462 }
463 
464 int yywrap(void) {return 1;}
465 
466 char	*newfile = 0;		/* filename for file copy */
467 char	*untilstr = 0;		/* string that terminates a thru */
468 int	thru	= 0;		/* 1 if copying thru macro */
469 Obj	*thrudef = 0;		/* macro being used */
470 
471 void copyfile(char *s)	/* remember file to start reading from */
472 {
473 	newfile = s;
474 }
475 
476 void copydef(Obj *p)	/* remember macro Obj */
477 {
478 	thrudef = p;
479 }
480 
481 Obj *copythru(char *s)	/* collect the macro name or body for thru */
482 {
483 	Obj *p;
484 	char *q;
485 
486 	p = lookup(s, 0);
487 	if (p != NULL) {
488 		if (p->type == DEFNAME) {
489 			p->val = addnewline(p->val);
490 			return p;
491 		} else
492 			ERROR "%s used as define and name", s FATAL;
493 	}
494 	/* have to collect the definition */
495 	pbstr(s);	/* first char is the delimiter */
496 	q = delimstr("thru body");
497 	p = lookup("nameless", 1);
498 	if (p != NULL)
499 		if (p->val)
500 			free(p->val);
501 	p->type = DEFNAME;
502 	p->val = q;
503 	p->val = addnewline(p->val);
504 	dprintf("installing nameless as `%s'\n", p->val);
505 	return p;
506 }
507 
508 char *addnewline(char *p)	/* add newline to end of p */
509 {
510 	int n;
511 
512 	n = strlen(p);
513 	if (p[n-1] != '\n') {
514 		p = realloc(p, n+2);
515 		p[n] = '\n';
516 		p[n+1] = '\0';
517 	}
518 	return p;
519 }
520 
521 void copyuntil(char *s)	/* string that terminates a thru */
522 {
523 	untilstr = s;
524 }
525 
526 void copy(void)	/* begin input from file, etc. */
527 {
528 	FILE *fin;
529 
530 	if (newfile) {
531 		if ((fin = fopen(newfile, "r")) == NULL)
532 			ERROR "can't open file %s", newfile FATAL;
533 		curfile++;
534 		curfile->fin = fin;
535 		curfile->fname = tostring(newfile);
536 		curfile->lineno = 0;
537 		printf(".lf 1 %s\n", curfile->fname);
538 		pushsrc(File, curfile->fname);
539 		newfile = 0;
540 	}
541 	if (thrudef) {
542 		thru = 1;
543 		begin = 1;	/* wrong place */
544 	}
545 }
546 
547 char	shellbuf[1000], *shellp;
548 
549 void shell_init(void)	/* set up to interpret a shell command */
550 {
551 	fprintf(tfd, "# shell cmd...\n");
552 	sprintf(shellbuf, "sh -c '");
553 	shellp = shellbuf + strlen(shellbuf);
554 }
555 
556 void shell_text(char *s)	/* add string to command being collected */
557 {
558 	/* fprintf(tfd, "#add <%s> to <%s>\n", s, shellbuf); */
559 	while (*s) {
560 		if (*s == '\'')	{	/* protect interior quotes */
561 			*shellp++ = '\'';
562 			*shellp++ = '\\';
563 			*shellp++ = '\'';
564 		}
565 		*shellp++ = *s++;
566 	}
567 }
568 
569 void shell_exec(void)	/* do it */
570 {
571 	/* fprintf(tfd, "# run <%s>\n", shellbuf); */
572 	*shellp++ = '\'';
573 	*shellp = '\0';
574 	system(shellbuf);
575 }
576