xref: /freebsd/contrib/one-true-awk/awkgram.y (revision 63a938566d524836885917d95bd491aa4400b181)
1 /****************************************************************
2 Copyright (C) Lucent Technologies 1997
3 All Rights Reserved
4 
5 Permission to use, copy, modify, and distribute this software and
6 its documentation for any purpose and without fee is hereby
7 granted, provided that the above copyright notice appear in all
8 copies and that both that the copyright notice and this
9 permission notice and warranty disclaimer appear in supporting
10 documentation, and that the name Lucent Technologies or any of
11 its entities not be used in advertising or publicity pertaining
12 to distribution of the software without specific, written prior
13 permission.
14 
15 LUCENT DISCLAIMS ALL WARRANTIES WITH REGARD TO THIS SOFTWARE,
16 INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS.
17 IN NO EVENT SHALL LUCENT OR ANY OF ITS ENTITIES BE LIABLE FOR ANY
18 SPECIAL, INDIRECT OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
19 WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER
20 IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION,
21 ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF
22 THIS SOFTWARE.
23 ****************************************************************/
24 
25 %{
26 #include <stdio.h>
27 #include <string.h>
28 #include "awk.h"
29 
30 void checkdup(Node *list, Cell *item);
31 int yywrap(void) { return(1); }
32 
33 Node	*beginloc = 0;
34 Node	*endloc = 0;
35 int	infunc	= 0;	/* = 1 if in arglist or body of func */
36 int	inloop	= 0;	/* = 1 if in while, for, do */
37 char	*curfname = 0;	/* current function name */
38 Node	*arglist = 0;	/* list of args for current function */
39 %}
40 
41 %union {
42 	Node	*p;
43 	Cell	*cp;
44 	int	i;
45 	char	*s;
46 }
47 
48 %token	<i>	FIRSTTOKEN	/* must be first */
49 %token	<p>	PROGRAM PASTAT PASTAT2 XBEGIN XEND
50 %token	<i>	NL ',' '{' '(' '|' ';' '/' ')' '}' '[' ']'
51 %token	<i>	ARRAY
52 %token	<i>	MATCH NOTMATCH MATCHOP
53 %token	<i>	FINAL DOT ALL CCL NCCL CHAR OR STAR QUEST PLUS EMPTYRE
54 %token	<i>	AND BOR APPEND EQ GE GT LE LT NE IN
55 %token	<i>	ARG BLTIN BREAK CLOSE CONTINUE DELETE DO EXIT FOR FUNC
56 %token	<i>	SUB GSUB IF INDEX LSUBSTR MATCHFCN NEXT NEXTFILE
57 %token	<i>	ADD MINUS MULT DIVIDE MOD
58 %token	<i>	ASSIGN ASGNOP ADDEQ SUBEQ MULTEQ DIVEQ MODEQ POWEQ
59 %token	<i>	PRINT PRINTF SPRINTF
60 %token	<p>	ELSE INTEST CONDEXPR
61 %token	<i>	POSTINCR PREINCR POSTDECR PREDECR
62 %token	<cp>	VAR IVAR VARNF CALL NUMBER STRING
63 %token	<s>	REGEXPR
64 
65 %type	<p>	pas pattern ppattern plist pplist patlist prarg term re
66 %type	<p>	pa_pat pa_stat pa_stats
67 %type	<s>	reg_expr
68 %type	<p>	simple_stmt opt_simple_stmt stmt stmtlist
69 %type	<p>	var varname funcname varlist
70 %type	<p>	for if else while
71 %type	<i>	do st
72 %type	<i>	pst opt_pst lbrace rbrace rparen comma nl opt_nl and bor
73 %type	<i>	subop print
74 
75 %right	ASGNOP
76 %right	'?'
77 %right	':'
78 %left	BOR
79 %left	AND
80 %left	GETLINE
81 %nonassoc APPEND EQ GE GT LE LT NE MATCHOP IN '|'
82 %left	ARG BLTIN BREAK CALL CLOSE CONTINUE DELETE DO EXIT FOR FUNC
83 %left	GSUB IF INDEX LSUBSTR MATCHFCN NEXT NUMBER
84 %left	PRINT PRINTF RETURN SPLIT SPRINTF STRING SUB SUBSTR
85 %left	REGEXPR VAR VARNF IVAR WHILE '('
86 %left	CAT
87 %left	'+' '-'
88 %left	'*' '/' '%'
89 %left	NOT UMINUS
90 %right	POWER
91 %right	DECR INCR
92 %left	INDIRECT
93 %token	LASTTOKEN	/* must be last */
94 
95 %%
96 
97 program:
98 	  pas	{ if (errorflag==0)
99 			winner = (Node *)stat3(PROGRAM, beginloc, $1, endloc); }
100 	| error	{ yyclearin; bracecheck(); SYNTAX("bailing out"); }
101 	;
102 
103 and:
104 	  AND | and NL
105 	;
106 
107 bor:
108 	  BOR | bor NL
109 	;
110 
111 comma:
112 	  ',' | comma NL
113 	;
114 
115 do:
116 	  DO | do NL
117 	;
118 
119 else:
120 	  ELSE | else NL
121 	;
122 
123 for:
124 	  FOR '(' opt_simple_stmt ';' opt_nl pattern ';' opt_nl opt_simple_stmt rparen {inloop++;} stmt
125 		{ --inloop; $$ = stat4(FOR, $3, notnull($6), $9, $12); }
126 	| FOR '(' opt_simple_stmt ';'  ';' opt_nl opt_simple_stmt rparen {inloop++;} stmt
127 		{ --inloop; $$ = stat4(FOR, $3, NIL, $7, $10); }
128 	| FOR '(' varname IN varname rparen {inloop++;} stmt
129 		{ --inloop; $$ = stat3(IN, $3, makearr($5), $8); }
130 	;
131 
132 funcname:
133 	  VAR	{ setfname($1); }
134 	| CALL	{ setfname($1); }
135 	;
136 
137 if:
138 	  IF '(' pattern rparen		{ $$ = notnull($3); }
139 	;
140 
141 lbrace:
142 	  '{' | lbrace NL
143 	;
144 
145 nl:
146 	  NL | nl NL
147 	;
148 
149 opt_nl:
150 	  /* empty */	{ $$ = 0; }
151 	| nl
152 	;
153 
154 opt_pst:
155 	  /* empty */	{ $$ = 0; }
156 	| pst
157 	;
158 
159 
160 opt_simple_stmt:
161 	  /* empty */			{ $$ = 0; }
162 	| simple_stmt
163 	;
164 
165 pas:
166 	  opt_pst			{ $$ = 0; }
167 	| opt_pst pa_stats opt_pst	{ $$ = $2; }
168 	;
169 
170 pa_pat:
171 	  pattern	{ $$ = notnull($1); }
172 	;
173 
174 pa_stat:
175 	  pa_pat			{ $$ = stat2(PASTAT, $1, stat2(PRINT, rectonode(), NIL)); }
176 	| pa_pat lbrace stmtlist '}'	{ $$ = stat2(PASTAT, $1, $3); }
177 	| pa_pat ',' opt_nl pa_pat		{ $$ = pa2stat($1, $4, stat2(PRINT, rectonode(), NIL)); }
178 	| pa_pat ',' opt_nl pa_pat lbrace stmtlist '}'	{ $$ = pa2stat($1, $4, $6); }
179 	| lbrace stmtlist '}'		{ $$ = stat2(PASTAT, NIL, $2); }
180 	| XBEGIN lbrace stmtlist '}'
181 		{ beginloc = linkum(beginloc, $3); $$ = 0; }
182 	| XEND lbrace stmtlist '}'
183 		{ endloc = linkum(endloc, $3); $$ = 0; }
184 	| FUNC funcname '(' varlist rparen {infunc++;} lbrace stmtlist '}'
185 		{ infunc--; curfname=0; defn((Cell *)$2, $4, $8); $$ = 0; }
186 	;
187 
188 pa_stats:
189 	  pa_stat
190 	| pa_stats opt_pst pa_stat	{ $$ = linkum($1, $3); }
191 	;
192 
193 patlist:
194 	  pattern
195 	| patlist comma pattern		{ $$ = linkum($1, $3); }
196 	;
197 
198 ppattern:
199 	  var ASGNOP ppattern		{ $$ = op2($2, $1, $3); }
200 	| ppattern '?' ppattern ':' ppattern %prec '?'
201 	 	{ $$ = op3(CONDEXPR, notnull($1), $3, $5); }
202 	| ppattern bor ppattern %prec BOR
203 		{ $$ = op2(BOR, notnull($1), notnull($3)); }
204 	| ppattern and ppattern %prec AND
205 		{ $$ = op2(AND, notnull($1), notnull($3)); }
206 	| ppattern MATCHOP reg_expr	{ $$ = op3($2, NIL, $1, (Node*)makedfa($3, 0)); }
207 	| ppattern MATCHOP ppattern
208 		{ if (constnode($3))
209 			$$ = op3($2, NIL, $1, (Node*)makedfa(strnode($3), 0));
210 		  else
211 			$$ = op3($2, (Node *)1, $1, $3); }
212 	| ppattern IN varname		{ $$ = op2(INTEST, $1, makearr($3)); }
213 	| '(' plist ')' IN varname	{ $$ = op2(INTEST, $2, makearr($5)); }
214 	| ppattern term %prec CAT	{ $$ = op2(CAT, $1, $2); }
215 	| re
216 	| term
217 	;
218 
219 pattern:
220 	  var ASGNOP pattern		{ $$ = op2($2, $1, $3); }
221 	| pattern '?' pattern ':' pattern %prec '?'
222 	 	{ $$ = op3(CONDEXPR, notnull($1), $3, $5); }
223 	| pattern bor pattern %prec BOR
224 		{ $$ = op2(BOR, notnull($1), notnull($3)); }
225 	| pattern and pattern %prec AND
226 		{ $$ = op2(AND, notnull($1), notnull($3)); }
227 	| pattern EQ pattern		{ $$ = op2($2, $1, $3); }
228 	| pattern GE pattern		{ $$ = op2($2, $1, $3); }
229 	| pattern GT pattern		{ $$ = op2($2, $1, $3); }
230 	| pattern LE pattern		{ $$ = op2($2, $1, $3); }
231 	| pattern LT pattern		{ $$ = op2($2, $1, $3); }
232 	| pattern NE pattern		{ $$ = op2($2, $1, $3); }
233 	| pattern MATCHOP reg_expr	{ $$ = op3($2, NIL, $1, (Node*)makedfa($3, 0)); }
234 	| pattern MATCHOP pattern
235 		{ if (constnode($3))
236 			$$ = op3($2, NIL, $1, (Node*)makedfa(strnode($3), 0));
237 		  else
238 			$$ = op3($2, (Node *)1, $1, $3); }
239 	| pattern IN varname		{ $$ = op2(INTEST, $1, makearr($3)); }
240 	| '(' plist ')' IN varname	{ $$ = op2(INTEST, $2, makearr($5)); }
241 	| pattern '|' GETLINE var	{
242 			if (safe) SYNTAX("cmd | getline is unsafe");
243 			else $$ = op3(GETLINE, $4, itonp($2), $1); }
244 	| pattern '|' GETLINE		{
245 			if (safe) SYNTAX("cmd | getline is unsafe");
246 			else $$ = op3(GETLINE, (Node*)0, itonp($2), $1); }
247 	| pattern term %prec CAT	{ $$ = op2(CAT, $1, $2); }
248 	| re
249 	| term
250 	;
251 
252 plist:
253 	  pattern comma pattern		{ $$ = linkum($1, $3); }
254 	| plist comma pattern		{ $$ = linkum($1, $3); }
255 	;
256 
257 pplist:
258 	  ppattern
259 	| pplist comma ppattern		{ $$ = linkum($1, $3); }
260 	;
261 
262 prarg:
263 	  /* empty */			{ $$ = rectonode(); }
264 	| pplist
265 	| '(' plist ')'			{ $$ = $2; }
266 	;
267 
268 print:
269 	  PRINT | PRINTF
270 	;
271 
272 pst:
273 	  NL | ';' | pst NL | pst ';'
274 	;
275 
276 rbrace:
277 	  '}' | rbrace NL
278 	;
279 
280 re:
281 	   reg_expr
282 		{ $$ = op3(MATCH, NIL, rectonode(), (Node*)makedfa($1, 0)); }
283 	| NOT re	{ $$ = op1(NOT, notnull($2)); }
284 	;
285 
286 reg_expr:
287 	  '/' {startreg();} REGEXPR '/'		{ $$ = $3; }
288 	;
289 
290 rparen:
291 	  ')' | rparen NL
292 	;
293 
294 simple_stmt:
295 	  print prarg '|' term		{
296 			if (safe) SYNTAX("print | is unsafe");
297 			else $$ = stat3($1, $2, itonp($3), $4); }
298 	| print prarg APPEND term	{
299 			if (safe) SYNTAX("print >> is unsafe");
300 			else $$ = stat3($1, $2, itonp($3), $4); }
301 	| print prarg GT term		{
302 			if (safe) SYNTAX("print > is unsafe");
303 			else $$ = stat3($1, $2, itonp($3), $4); }
304 	| print prarg			{ $$ = stat3($1, $2, NIL, NIL); }
305 	| DELETE varname '[' patlist ']' { $$ = stat2(DELETE, makearr($2), $4); }
306 	| DELETE varname		 { $$ = stat2(DELETE, makearr($2), 0); }
307 	| pattern			{ $$ = exptostat($1); }
308 	| error				{ yyclearin; SYNTAX("illegal statement"); }
309 	;
310 
311 st:
312 	  nl
313 	| ';' opt_nl
314 	;
315 
316 stmt:
317 	  BREAK st		{ if (!inloop) SYNTAX("break illegal outside of loops");
318 				  $$ = stat1(BREAK, NIL); }
319 	| CONTINUE st		{  if (!inloop) SYNTAX("continue illegal outside of loops");
320 				  $$ = stat1(CONTINUE, NIL); }
321 	| do {inloop++;} stmt {--inloop;} WHILE '(' pattern ')' st
322 		{ $$ = stat2(DO, $3, notnull($7)); }
323 	| EXIT pattern st	{ $$ = stat1(EXIT, $2); }
324 	| EXIT st		{ $$ = stat1(EXIT, NIL); }
325 	| for
326 	| if stmt else stmt	{ $$ = stat3(IF, $1, $2, $4); }
327 	| if stmt		{ $$ = stat3(IF, $1, $2, NIL); }
328 	| lbrace stmtlist rbrace { $$ = $2; }
329 	| NEXT st	{ if (infunc)
330 				SYNTAX("next is illegal inside a function");
331 			  $$ = stat1(NEXT, NIL); }
332 	| NEXTFILE st	{ if (infunc)
333 				SYNTAX("nextfile is illegal inside a function");
334 			  $$ = stat1(NEXTFILE, NIL); }
335 	| RETURN pattern st	{ $$ = stat1(RETURN, $2); }
336 	| RETURN st		{ $$ = stat1(RETURN, NIL); }
337 	| simple_stmt st
338 	| while {inloop++;} stmt	{ --inloop; $$ = stat2(WHILE, $1, $3); }
339 	| ';' opt_nl		{ $$ = 0; }
340 	;
341 
342 stmtlist:
343 	  stmt
344 	| stmtlist stmt		{ $$ = linkum($1, $2); }
345 	;
346 
347 subop:
348 	  SUB | GSUB
349 	;
350 
351 term:
352  	  term '/' ASGNOP term		{ $$ = op2(DIVEQ, $1, $4); }
353  	| term '+' term			{ $$ = op2(ADD, $1, $3); }
354 	| term '-' term			{ $$ = op2(MINUS, $1, $3); }
355 	| term '*' term			{ $$ = op2(MULT, $1, $3); }
356 	| term '/' term			{ $$ = op2(DIVIDE, $1, $3); }
357 	| term '%' term			{ $$ = op2(MOD, $1, $3); }
358 	| term POWER term		{ $$ = op2(POWER, $1, $3); }
359 	| '-' term %prec UMINUS		{ $$ = op1(UMINUS, $2); }
360 	| '+' term %prec UMINUS		{ $$ = $2; }
361 	| NOT term %prec UMINUS		{ $$ = op1(NOT, notnull($2)); }
362 	| BLTIN '(' ')'			{ $$ = op2(BLTIN, itonp($1), rectonode()); }
363 	| BLTIN '(' patlist ')'		{ $$ = op2(BLTIN, itonp($1), $3); }
364 	| BLTIN				{ $$ = op2(BLTIN, itonp($1), rectonode()); }
365 	| CALL '(' ')'			{ $$ = op2(CALL, celltonode($1,CVAR), NIL); }
366 	| CALL '(' patlist ')'		{ $$ = op2(CALL, celltonode($1,CVAR), $3); }
367 	| CLOSE term			{ $$ = op1(CLOSE, $2); }
368 	| DECR var			{ $$ = op1(PREDECR, $2); }
369 	| INCR var			{ $$ = op1(PREINCR, $2); }
370 	| var DECR			{ $$ = op1(POSTDECR, $1); }
371 	| var INCR			{ $$ = op1(POSTINCR, $1); }
372 	| GETLINE var LT term		{ $$ = op3(GETLINE, $2, itonp($3), $4); }
373 	| GETLINE LT term		{ $$ = op3(GETLINE, NIL, itonp($2), $3); }
374 	| GETLINE var			{ $$ = op3(GETLINE, $2, NIL, NIL); }
375 	| GETLINE			{ $$ = op3(GETLINE, NIL, NIL, NIL); }
376 	| INDEX '(' pattern comma pattern ')'
377 		{ $$ = op2(INDEX, $3, $5); }
378 	| INDEX '(' pattern comma reg_expr ')'
379 		{ SYNTAX("index() doesn't permit regular expressions");
380 		  $$ = op2(INDEX, $3, (Node*)$5); }
381 	| '(' pattern ')'		{ $$ = $2; }
382 	| MATCHFCN '(' pattern comma reg_expr ')'
383 		{ $$ = op3(MATCHFCN, NIL, $3, (Node*)makedfa($5, 1)); }
384 	| MATCHFCN '(' pattern comma pattern ')'
385 		{ if (constnode($5))
386 			$$ = op3(MATCHFCN, NIL, $3, (Node*)makedfa(strnode($5), 1));
387 		  else
388 			$$ = op3(MATCHFCN, (Node *)1, $3, $5); }
389 	| NUMBER			{ $$ = celltonode($1, CCON); }
390 	| SPLIT '(' pattern comma varname comma pattern ')'     /* string */
391 		{ $$ = op4(SPLIT, $3, makearr($5), $7, (Node*)STRING); }
392 	| SPLIT '(' pattern comma varname comma reg_expr ')'    /* const /regexp/ */
393 		{ $$ = op4(SPLIT, $3, makearr($5), (Node*)makedfa($7, 1), (Node *)REGEXPR); }
394 	| SPLIT '(' pattern comma varname ')'
395 		{ $$ = op4(SPLIT, $3, makearr($5), NIL, (Node*)STRING); }  /* default */
396 	| SPRINTF '(' patlist ')'	{ $$ = op1($1, $3); }
397 	| STRING	 		{ $$ = celltonode($1, CCON); }
398 	| subop '(' reg_expr comma pattern ')'
399 		{ $$ = op4($1, NIL, (Node*)makedfa($3, 1), $5, rectonode()); }
400 	| subop '(' pattern comma pattern ')'
401 		{ if (constnode($3))
402 			$$ = op4($1, NIL, (Node*)makedfa(strnode($3), 1), $5, rectonode());
403 		  else
404 			$$ = op4($1, (Node *)1, $3, $5, rectonode()); }
405 	| subop '(' reg_expr comma pattern comma var ')'
406 		{ $$ = op4($1, NIL, (Node*)makedfa($3, 1), $5, $7); }
407 	| subop '(' pattern comma pattern comma var ')'
408 		{ if (constnode($3))
409 			$$ = op4($1, NIL, (Node*)makedfa(strnode($3), 1), $5, $7);
410 		  else
411 			$$ = op4($1, (Node *)1, $3, $5, $7); }
412 	| SUBSTR '(' pattern comma pattern comma pattern ')'
413 		{ $$ = op3(SUBSTR, $3, $5, $7); }
414 	| SUBSTR '(' pattern comma pattern ')'
415 		{ $$ = op3(SUBSTR, $3, $5, NIL); }
416 	| var
417 	;
418 
419 var:
420 	  varname
421 	| varname '[' patlist ']'	{ $$ = op2(ARRAY, makearr($1), $3); }
422 	| IVAR				{ $$ = op1(INDIRECT, celltonode($1, CVAR)); }
423 	| INDIRECT term	 		{ $$ = op1(INDIRECT, $2); }
424 	;
425 
426 varlist:
427 	  /* nothing */		{ arglist = $$ = 0; }
428 	| VAR			{ arglist = $$ = celltonode($1,CVAR); }
429 	| varlist comma VAR	{
430 			checkdup($1, $3);
431 			arglist = $$ = linkum($1,celltonode($3,CVAR)); }
432 	;
433 
434 varname:
435 	  VAR			{ $$ = celltonode($1, CVAR); }
436 	| ARG 			{ $$ = op1(ARG, itonp($1)); }
437 	| VARNF			{ $$ = op1(VARNF, (Node *) $1); }
438 	;
439 
440 
441 while:
442 	  WHILE '(' pattern rparen	{ $$ = notnull($3); }
443 	;
444 
445 %%
446 
447 void setfname(Cell *p)
448 {
449 	if (isarr(p))
450 		SYNTAX("%s is an array, not a function", p->nval);
451 	else if (isfcn(p))
452 		SYNTAX("you can't define function %s more than once", p->nval);
453 	curfname = p->nval;
454 }
455 
456 int constnode(Node *p)
457 {
458 	return isvalue(p) && ((Cell *) (p->narg[0]))->csub == CCON;
459 }
460 
461 char *strnode(Node *p)
462 {
463 	return ((Cell *)(p->narg[0]))->sval;
464 }
465 
466 Node *notnull(Node *n)
467 {
468 	switch (n->nobj) {
469 	case LE: case LT: case EQ: case NE: case GT: case GE:
470 	case BOR: case AND: case NOT:
471 		return n;
472 	default:
473 		return op2(NE, n, nullnode);
474 	}
475 }
476 
477 void checkdup(Node *vl, Cell *cp)	/* check if name already in list */
478 {
479 	char *s = cp->nval;
480 	for ( ; vl; vl = vl->nnext) {
481 		if (strcmp(s, ((Cell *)(vl->narg[0]))->nval) == 0) {
482 			SYNTAX("duplicate argument %s", s);
483 			break;
484 		}
485 	}
486 }
487