xref: /freebsd/cddl/contrib/opensolaris/lib/libdtrace/common/dt_lex.l (revision 57718be8fa0bd5edc11ab9a72e68cc71982939a6)
1 %{
2 /*
3  * CDDL HEADER START
4  *
5  * The contents of this file are subject to the terms of the
6  * Common Development and Distribution License (the "License").
7  * You may not use this file except in compliance with the License.
8  *
9  * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
10  * or http://www.opensolaris.org/os/licensing.
11  * See the License for the specific language governing permissions
12  * and limitations under the License.
13  *
14  * When distributing Covered Code, include this CDDL HEADER in each
15  * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
16  * If applicable, add the following below this CDDL HEADER, with the
17  * fields enclosed by brackets "[]" replaced with your own identifying
18  * information: Portions Copyright [yyyy] [name of copyright owner]
19  *
20  * CDDL HEADER END
21  */
22 
23 /*
24  * Copyright (c) 2003, 2010, Oracle and/or its affiliates. All rights reserved.
25  */
26 /*
27  * Copyright (c) 2013 by Delphix. All rights reserved.
28  * Copyright (c) 2013, Joyent, Inc. All rights reserved.
29  */
30 
31 #include <string.h>
32 #include <stdlib.h>
33 #include <stdio.h>
34 #include <assert.h>
35 #include <ctype.h>
36 #include <errno.h>
37 
38 #include <dt_impl.h>
39 #include <dt_grammar.h>
40 #include <dt_parser.h>
41 #include <dt_string.h>
42 
43 /*
44  * We need to undefine lex's input and unput macros so that references to these
45  * call the functions provided at the end of this source file.
46  */
47 #if defined(sun)
48 #undef input
49 #undef unput
50 #else
51 /*
52  * Define YY_INPUT for flex since input() can't be re-defined.
53  */
54 #define YY_INPUT(buf,result,max_size) \
55 	if (yypcb->pcb_fileptr != NULL) { \
56 		if (((result = fread(buf, 1, max_size, yypcb->pcb_fileptr)) == 0) \
57 		    && ferror(yypcb->pcb_fileptr)) \
58 			longjmp(yypcb->pcb_jmpbuf, EDT_FIO); \
59 	} else { \
60 		int n; \
61 		for (n = 0; n < max_size && \
62 		    yypcb->pcb_strptr < yypcb->pcb_string + yypcb->pcb_strlen; n++) \
63 			buf[n] = *yypcb->pcb_strptr++; \
64 		result = n; \
65 	}
66 /*
67  * Do not EOF let tokens to be put back. This does not work with flex.
68  * On the other hand, leaving current buffer in same state it was when
69  * last EOF was received guarantees that input() will keep returning EOF
70  * for all subsequent invocations, which is the effect desired.
71  */
72 #undef  unput
73 #define unput(c)					\
74 	do {						\
75 		int _c = c;				\
76 		if (_c != EOF)				\
77 			yyunput(_c, yytext_ptr);	\
78 	} while(0)
79 #endif
80 
81 static int id_or_type(const char *);
82 #if defined(sun)
83 static int input(void);
84 static void unput(int);
85 #endif
86 
87 /*
88  * We first define a set of labeled states for use in the D lexer and then a
89  * set of regular expressions to simplify things below. The lexer states are:
90  *
91  * S0 - D program clause and expression lexing
92  * S1 - D comments (i.e. skip everything until end of comment)
93  * S2 - D program outer scope (probe specifiers and declarations)
94  * S3 - D control line parsing (i.e. after ^# is seen but before \n)
95  * S4 - D control line scan (locate control directives only and invoke S3)
96  */
97 %}
98 
99 %e 1500		/* maximum nodes */
100 %p 4900		/* maximum positions */
101 %n 600		/* maximum states */
102 %a 3000		/* maximum transitions */
103 
104 %s S0 S1 S2 S3 S4
105 
106 RGX_AGG		"@"[a-zA-Z_][0-9a-zA-Z_]*
107 RGX_PSPEC	[-$:a-zA-Z_.?*\\\[\]!][-$:0-9a-zA-Z_.`?*\\\[\]!]*
108 RGX_ALTIDENT	[a-zA-Z_][0-9a-zA-Z_]*
109 RGX_LMID	LM[0-9a-fA-F]+`
110 RGX_MOD_IDENT	[a-zA-Z_`][0-9a-z.A-Z_`]*`
111 RGX_IDENT	[a-zA-Z_`][0-9a-zA-Z_`]*
112 RGX_INT		([0-9]+|0[xX][0-9A-Fa-f]+)[uU]?[lL]?[lL]?
113 RGX_FP		([0-9]+("."?)[0-9]*|"."[0-9]+)((e|E)("+"|-)?[0-9]+)?[fFlL]?
114 RGX_WS		[\f\n\r\t\v ]
115 RGX_STR		([^"\\\n]|\\[^"\n]|\\\")*
116 RGX_CHR		([^'\\\n]|\\[^'\n]|\\')*
117 RGX_INTERP	^[\f\t\v ]*#!.*
118 RGX_CTL		^[\f\t\v ]*#
119 
120 %%
121 
122 %{
123 
124 /*
125  * We insert a special prologue into yylex() itself: if the pcb contains a
126  * context token, we return that prior to running the normal lexer.  This
127  * allows libdtrace to force yacc into one of our three parsing contexts: D
128  * expression (DT_CTX_DEXPR), D program (DT_CTX_DPROG) or D type (DT_CTX_DTYPE).
129  * Once the token is returned, we clear it so this only happens once.
130  */
131 if (yypcb->pcb_token != 0) {
132 	int tok = yypcb->pcb_token;
133 	yypcb->pcb_token = 0;
134 	return (tok);
135 }
136 
137 %}
138 
139 <S0>auto	return (DT_KEY_AUTO);
140 <S0>break	return (DT_KEY_BREAK);
141 <S0>case	return (DT_KEY_CASE);
142 <S0>char	return (DT_KEY_CHAR);
143 <S0>const	return (DT_KEY_CONST);
144 <S0>continue	return (DT_KEY_CONTINUE);
145 <S0>counter	return (DT_KEY_COUNTER);
146 <S0>default	return (DT_KEY_DEFAULT);
147 <S0>do		return (DT_KEY_DO);
148 <S0>double	return (DT_KEY_DOUBLE);
149 <S0>else	return (DT_KEY_ELSE);
150 <S0>enum	return (DT_KEY_ENUM);
151 <S0>extern	return (DT_KEY_EXTERN);
152 <S0>float	return (DT_KEY_FLOAT);
153 <S0>for		return (DT_KEY_FOR);
154 <S0>goto	return (DT_KEY_GOTO);
155 <S0>if		return (DT_KEY_IF);
156 <S0>import	return (DT_KEY_IMPORT);
157 <S0>inline	return (DT_KEY_INLINE);
158 <S0>int		return (DT_KEY_INT);
159 <S0>long	return (DT_KEY_LONG);
160 <S0>offsetof	return (DT_TOK_OFFSETOF);
161 <S0>probe	return (DT_KEY_PROBE);
162 <S0>provider	return (DT_KEY_PROVIDER);
163 <S0>register	return (DT_KEY_REGISTER);
164 <S0>restrict	return (DT_KEY_RESTRICT);
165 <S0>return	return (DT_KEY_RETURN);
166 <S0>self	return (DT_KEY_SELF);
167 <S0>short	return (DT_KEY_SHORT);
168 <S0>signed	return (DT_KEY_SIGNED);
169 <S0>sizeof	return (DT_TOK_SIZEOF);
170 <S0>static	return (DT_KEY_STATIC);
171 <S0>string	return (DT_KEY_STRING);
172 <S0>stringof	return (DT_TOK_STRINGOF);
173 <S0>struct	return (DT_KEY_STRUCT);
174 <S0>switch	return (DT_KEY_SWITCH);
175 <S0>this	return (DT_KEY_THIS);
176 <S0>translator	return (DT_KEY_XLATOR);
177 <S0>typedef	return (DT_KEY_TYPEDEF);
178 <S0>union	return (DT_KEY_UNION);
179 <S0>unsigned	return (DT_KEY_UNSIGNED);
180 <S0>userland	return (DT_KEY_USERLAND);
181 <S0>void	return (DT_KEY_VOID);
182 <S0>volatile	return (DT_KEY_VOLATILE);
183 <S0>while	return (DT_KEY_WHILE);
184 <S0>xlate	return (DT_TOK_XLATE);
185 
186 <S2>auto	{ yybegin(YYS_EXPR);	return (DT_KEY_AUTO); }
187 <S2>char	{ yybegin(YYS_EXPR);	return (DT_KEY_CHAR); }
188 <S2>const	{ yybegin(YYS_EXPR);	return (DT_KEY_CONST); }
189 <S2>counter	{ yybegin(YYS_DEFINE);	return (DT_KEY_COUNTER); }
190 <S2>double	{ yybegin(YYS_EXPR);	return (DT_KEY_DOUBLE); }
191 <S2>enum	{ yybegin(YYS_EXPR);	return (DT_KEY_ENUM); }
192 <S2>extern	{ yybegin(YYS_EXPR);	return (DT_KEY_EXTERN); }
193 <S2>float	{ yybegin(YYS_EXPR);	return (DT_KEY_FLOAT); }
194 <S2>import	{ yybegin(YYS_EXPR);	return (DT_KEY_IMPORT); }
195 <S2>inline	{ yybegin(YYS_DEFINE);	return (DT_KEY_INLINE); }
196 <S2>int		{ yybegin(YYS_EXPR);	return (DT_KEY_INT); }
197 <S2>long	{ yybegin(YYS_EXPR);	return (DT_KEY_LONG); }
198 <S2>provider	{ yybegin(YYS_DEFINE);	return (DT_KEY_PROVIDER); }
199 <S2>register	{ yybegin(YYS_EXPR);	return (DT_KEY_REGISTER); }
200 <S2>restrict	{ yybegin(YYS_EXPR);	return (DT_KEY_RESTRICT); }
201 <S2>self	{ yybegin(YYS_EXPR);	return (DT_KEY_SELF); }
202 <S2>short	{ yybegin(YYS_EXPR);	return (DT_KEY_SHORT); }
203 <S2>signed	{ yybegin(YYS_EXPR);	return (DT_KEY_SIGNED); }
204 <S2>static	{ yybegin(YYS_EXPR);	return (DT_KEY_STATIC); }
205 <S2>string	{ yybegin(YYS_EXPR);	return (DT_KEY_STRING); }
206 <S2>struct	{ yybegin(YYS_EXPR);	return (DT_KEY_STRUCT); }
207 <S2>this	{ yybegin(YYS_EXPR);	return (DT_KEY_THIS); }
208 <S2>translator	{ yybegin(YYS_DEFINE);	return (DT_KEY_XLATOR); }
209 <S2>typedef	{ yybegin(YYS_EXPR);	return (DT_KEY_TYPEDEF); }
210 <S2>union	{ yybegin(YYS_EXPR);	return (DT_KEY_UNION); }
211 <S2>unsigned	{ yybegin(YYS_EXPR);	return (DT_KEY_UNSIGNED); }
212 <S2>void	{ yybegin(YYS_EXPR);	return (DT_KEY_VOID); }
213 <S2>volatile	{ yybegin(YYS_EXPR);	return (DT_KEY_VOLATILE); }
214 
215 <S0>"$$"[0-9]+	{
216 			int i = atoi(yytext + 2);
217 			char *v = "";
218 
219 			/*
220 			 * A macro argument reference substitutes the text of
221 			 * an argument in place of the current token.  When we
222 			 * see $$<d> we fetch the saved string from pcb_sargv
223 			 * (or use the default argument if the option has been
224 			 * set and the argument hasn't been specified) and
225 			 * return a token corresponding to this string.
226 			 */
227 			if (i < 0 || (i >= yypcb->pcb_sargc &&
228 			    !(yypcb->pcb_cflags & DTRACE_C_DEFARG))) {
229 				xyerror(D_MACRO_UNDEF, "macro argument %s is "
230 				    "not defined\n", yytext);
231 			}
232 
233 			if (i < yypcb->pcb_sargc) {
234 				v = yypcb->pcb_sargv[i]; /* get val from pcb */
235 				yypcb->pcb_sflagv[i] |= DT_IDFLG_REF;
236 			}
237 
238 			if ((yylval.l_str = strdup(v)) == NULL)
239 				longjmp(yypcb->pcb_jmpbuf, EDT_NOMEM);
240 
241 			(void) stresc2chr(yylval.l_str);
242 			return (DT_TOK_STRING);
243 		}
244 
245 <S0>"$"[0-9]+	{
246 			int i = atoi(yytext + 1);
247 			char *p, *v = "0";
248 
249 			/*
250 			 * A macro argument reference substitutes the text of
251 			 * one identifier or integer pattern for another.  When
252 			 * we see $<d> we fetch the saved string from pcb_sargv
253 			 * (or use the default argument if the option has been
254 			 * set and the argument hasn't been specified) and
255 			 * return a token corresponding to this string.
256 			 */
257 			if (i < 0 || (i >= yypcb->pcb_sargc &&
258 			    !(yypcb->pcb_cflags & DTRACE_C_DEFARG))) {
259 				xyerror(D_MACRO_UNDEF, "macro argument %s is "
260 				    "not defined\n", yytext);
261 			}
262 
263 			if (i < yypcb->pcb_sargc) {
264 				v = yypcb->pcb_sargv[i]; /* get val from pcb */
265 				yypcb->pcb_sflagv[i] |= DT_IDFLG_REF;
266 			}
267 
268 			/*
269 			 * If the macro text is not a valid integer or ident,
270 			 * then we treat it as a string.  The string may be
271 			 * optionally enclosed in quotes, which we strip.
272 			 */
273 			if (strbadidnum(v)) {
274 				size_t len = strlen(v);
275 
276 				if (len != 1 && *v == '"' && v[len - 1] == '"')
277 					yylval.l_str = strndup(v + 1, len - 2);
278 				else
279 					yylval.l_str = strndup(v, len);
280 
281 				if (yylval.l_str == NULL)
282 					longjmp(yypcb->pcb_jmpbuf, EDT_NOMEM);
283 
284 				(void) stresc2chr(yylval.l_str);
285 				return (DT_TOK_STRING);
286 			}
287 
288 			/*
289 			 * If the macro text is not a string an begins with a
290 			 * digit or a +/- sign, process it as an integer token.
291 			 */
292 			if (isdigit(v[0]) || v[0] == '-' || v[0] == '+') {
293 				if (isdigit(v[0]))
294 					yyintprefix = 0;
295 				else
296 					yyintprefix = *v++;
297 
298 				errno = 0;
299 				yylval.l_int = strtoull(v, &p, 0);
300 				(void) strncpy(yyintsuffix, p,
301 				    sizeof (yyintsuffix));
302 				yyintdecimal = *v != '0';
303 
304 				if (errno == ERANGE) {
305 					xyerror(D_MACRO_OFLOW, "macro argument"
306 					    " %s constant %s results in integer"
307 					    " overflow\n", yytext, v);
308 				}
309 
310 				return (DT_TOK_INT);
311 			}
312 
313 			return (id_or_type(v));
314 		}
315 
316 <S0>"$$"{RGX_IDENT} {
317 			dt_ident_t *idp = dt_idhash_lookup(
318 			    yypcb->pcb_hdl->dt_macros, yytext + 2);
319 
320 			char s[16]; /* enough for UINT_MAX + \0 */
321 
322 			if (idp == NULL) {
323 				xyerror(D_MACRO_UNDEF, "macro variable %s "
324 				    "is not defined\n", yytext);
325 			}
326 
327 			/*
328 			 * For the moment, all current macro variables are of
329 			 * type id_t (refer to dtrace_update() for details).
330 			 */
331 			(void) snprintf(s, sizeof (s), "%u", idp->di_id);
332 			if ((yylval.l_str = strdup(s)) == NULL)
333 				longjmp(yypcb->pcb_jmpbuf, EDT_NOMEM);
334 
335 			return (DT_TOK_STRING);
336 		}
337 
338 <S0>"$"{RGX_IDENT} {
339 			dt_ident_t *idp = dt_idhash_lookup(
340 			    yypcb->pcb_hdl->dt_macros, yytext + 1);
341 
342 			if (idp == NULL) {
343 				xyerror(D_MACRO_UNDEF, "macro variable %s "
344 				    "is not defined\n", yytext);
345 			}
346 
347 			/*
348 			 * For the moment, all current macro variables are of
349 			 * type id_t (refer to dtrace_update() for details).
350 			 */
351 			yylval.l_int = (intmax_t)(int)idp->di_id;
352 			yyintprefix = 0;
353 			yyintsuffix[0] = '\0';
354 			yyintdecimal = 1;
355 
356 			return (DT_TOK_INT);
357 		}
358 
359 <S0>{RGX_IDENT} |
360 <S0>{RGX_MOD_IDENT}{RGX_IDENT} |
361 <S0>{RGX_MOD_IDENT} {
362 			return (id_or_type(yytext));
363 		}
364 
365 <S0>{RGX_AGG}	{
366 			if ((yylval.l_str = strdup(yytext)) == NULL)
367 				longjmp(yypcb->pcb_jmpbuf, EDT_NOMEM);
368 			return (DT_TOK_AGG);
369 		}
370 
371 <S0>"@"		{
372 			if ((yylval.l_str = strdup("@_")) == NULL)
373 				longjmp(yypcb->pcb_jmpbuf, EDT_NOMEM);
374 			return (DT_TOK_AGG);
375 		}
376 
377 <S0>{RGX_INT}	|
378 <S2>{RGX_INT}	|
379 <S3>{RGX_INT}	{
380 			char *p;
381 
382 			errno = 0;
383 			yylval.l_int = strtoull(yytext, &p, 0);
384 			yyintprefix = 0;
385 			(void) strncpy(yyintsuffix, p, sizeof (yyintsuffix));
386 			yyintdecimal = yytext[0] != '0';
387 
388 			if (errno == ERANGE) {
389 				xyerror(D_INT_OFLOW, "constant %s results in "
390 				    "integer overflow\n", yytext);
391 			}
392 
393 			if (*p != '\0' && strchr("uUlL", *p) == NULL) {
394 				xyerror(D_INT_DIGIT, "constant %s contains "
395 				    "invalid digit %c\n", yytext, *p);
396 			}
397 
398 			if ((YYSTATE) != S3)
399 				return (DT_TOK_INT);
400 
401 			yypragma = dt_node_link(yypragma,
402 			    dt_node_int(yylval.l_int));
403 		}
404 
405 <S0>{RGX_FP}	yyerror("floating-point constants are not permitted\n");
406 
407 <S0>\"{RGX_STR}$ |
408 <S3>\"{RGX_STR}$ xyerror(D_STR_NL, "newline encountered in string literal");
409 
410 <S0>\"{RGX_STR}\" |
411 <S3>\"{RGX_STR}\" {
412 			/*
413 			 * Quoted string -- convert C escape sequences and
414 			 * return the string as a token.
415 			 */
416 			yylval.l_str = strndup(yytext + 1, yyleng - 2);
417 
418 			if (yylval.l_str == NULL)
419 				longjmp(yypcb->pcb_jmpbuf, EDT_NOMEM);
420 
421 			(void) stresc2chr(yylval.l_str);
422 			if ((YYSTATE) != S3)
423 				return (DT_TOK_STRING);
424 
425 			yypragma = dt_node_link(yypragma,
426 			    dt_node_string(yylval.l_str));
427 		}
428 
429 <S0>'{RGX_CHR}$	xyerror(D_CHR_NL, "newline encountered in character constant");
430 
431 <S0>'{RGX_CHR}'	{
432 			char *s, *p, *q;
433 			size_t nbytes;
434 
435 			/*
436 			 * Character constant -- convert C escape sequences and
437 			 * return the character as an integer immediate value.
438 			 */
439 			if (yyleng == 2)
440 				xyerror(D_CHR_NULL, "empty character constant");
441 
442 			s = yytext + 1;
443 			yytext[yyleng - 1] = '\0';
444 			nbytes = stresc2chr(s);
445 			yylval.l_int = 0;
446 			yyintprefix = 0;
447 			yyintsuffix[0] = '\0';
448 			yyintdecimal = 1;
449 
450 			if (nbytes > sizeof (yylval.l_int)) {
451 				xyerror(D_CHR_OFLOW, "character constant is "
452 				    "too long");
453 			}
454 #if BYTE_ORDER == _LITTLE_ENDIAN
455 			p = ((char *)&yylval.l_int) + nbytes - 1;
456 			for (q = s; nbytes != 0; nbytes--)
457 				*p-- = *q++;
458 #else
459 			bcopy(s, ((char *)&yylval.l_int) +
460 			    sizeof (yylval.l_int) - nbytes, nbytes);
461 #endif
462 			return (DT_TOK_INT);
463 		}
464 
465 <S0>"/*"	|
466 <S2>"/*"	{
467 			yypcb->pcb_cstate = (YYSTATE);
468 			BEGIN(S1);
469 		}
470 
471 <S0>{RGX_INTERP} |
472 <S2>{RGX_INTERP} ;	/* discard any #! lines */
473 
474 <S0>{RGX_CTL}	|
475 <S2>{RGX_CTL}	|
476 <S4>{RGX_CTL}	{
477 			assert(yypragma == NULL);
478 			yypcb->pcb_cstate = (YYSTATE);
479 			BEGIN(S3);
480 		}
481 
482 <S4>.		;	/* discard */
483 <S4>"\n"	;	/* discard */
484 
485 <S0>"/"		{
486 			int c, tok;
487 
488 			/*
489 			 * The use of "/" as the predicate delimiter and as the
490 			 * integer division symbol requires special lookahead
491 			 * to avoid a shift/reduce conflict in the D grammar.
492 			 * We look ahead to the next non-whitespace character.
493 			 * If we encounter EOF, ";", "{", or "/", then this "/"
494 			 * closes the predicate and we return DT_TOK_EPRED.
495 			 * If we encounter anything else, it's DT_TOK_DIV.
496 			 */
497 			while ((c = input()) != 0) {
498 				if (strchr("\f\n\r\t\v ", c) == NULL)
499 					break;
500 			}
501 
502 			if (c == 0 || c == ';' || c == '{' || c == '/') {
503 				if (yypcb->pcb_parens != 0) {
504 					yyerror("closing ) expected in "
505 					    "predicate before /\n");
506 				}
507 				if (yypcb->pcb_brackets != 0) {
508 					yyerror("closing ] expected in "
509 					    "predicate before /\n");
510 				}
511 				tok = DT_TOK_EPRED;
512 			} else
513 				tok = DT_TOK_DIV;
514 
515 			unput(c);
516 			return (tok);
517 		}
518 
519 <S0>"("		{
520 			yypcb->pcb_parens++;
521 			return (DT_TOK_LPAR);
522 		}
523 
524 <S0>")"		{
525 			if (--yypcb->pcb_parens < 0)
526 				yyerror("extra ) in input stream\n");
527 			return (DT_TOK_RPAR);
528 		}
529 
530 <S0>"["		{
531 			yypcb->pcb_brackets++;
532 			return (DT_TOK_LBRAC);
533 		}
534 
535 <S0>"]"		{
536 			if (--yypcb->pcb_brackets < 0)
537 				yyerror("extra ] in input stream\n");
538 			return (DT_TOK_RBRAC);
539 		}
540 
541 <S0>"{"		|
542 <S2>"{"		{
543 			yypcb->pcb_braces++;
544 			return ('{');
545 		}
546 
547 <S0>"}"		{
548 			if (--yypcb->pcb_braces < 0)
549 				yyerror("extra } in input stream\n");
550 			return ('}');
551 		}
552 
553 <S0>"|"		return (DT_TOK_BOR);
554 <S0>"^"		return (DT_TOK_XOR);
555 <S0>"&"		return (DT_TOK_BAND);
556 <S0>"&&"	return (DT_TOK_LAND);
557 <S0>"^^"	return (DT_TOK_LXOR);
558 <S0>"||"	return (DT_TOK_LOR);
559 <S0>"=="	return (DT_TOK_EQU);
560 <S0>"!="	return (DT_TOK_NEQ);
561 <S0>"<"		return (DT_TOK_LT);
562 <S0>"<="	return (DT_TOK_LE);
563 <S0>">"		return (DT_TOK_GT);
564 <S0>">="	return (DT_TOK_GE);
565 <S0>"<<"	return (DT_TOK_LSH);
566 <S0>">>"	return (DT_TOK_RSH);
567 <S0>"+"		return (DT_TOK_ADD);
568 <S0>"-"		return (DT_TOK_SUB);
569 <S0>"*"		return (DT_TOK_MUL);
570 <S0>"%"		return (DT_TOK_MOD);
571 <S0>"~"		return (DT_TOK_BNEG);
572 <S0>"!"		return (DT_TOK_LNEG);
573 <S0>"?"		return (DT_TOK_QUESTION);
574 <S0>":"		return (DT_TOK_COLON);
575 <S0>"."		return (DT_TOK_DOT);
576 <S0>"->"	return (DT_TOK_PTR);
577 <S0>"="		return (DT_TOK_ASGN);
578 <S0>"+="	return (DT_TOK_ADD_EQ);
579 <S0>"-="	return (DT_TOK_SUB_EQ);
580 <S0>"*="	return (DT_TOK_MUL_EQ);
581 <S0>"/="	return (DT_TOK_DIV_EQ);
582 <S0>"%="	return (DT_TOK_MOD_EQ);
583 <S0>"&="	return (DT_TOK_AND_EQ);
584 <S0>"^="	return (DT_TOK_XOR_EQ);
585 <S0>"|="	return (DT_TOK_OR_EQ);
586 <S0>"<<="	return (DT_TOK_LSH_EQ);
587 <S0>">>="	return (DT_TOK_RSH_EQ);
588 <S0>"++"	return (DT_TOK_ADDADD);
589 <S0>"--"	return (DT_TOK_SUBSUB);
590 <S0>"..."	return (DT_TOK_ELLIPSIS);
591 <S0>","		return (DT_TOK_COMMA);
592 <S0>";"		return (';');
593 <S0>{RGX_WS}	; /* discard */
594 <S0>"\\"\n	; /* discard */
595 <S0>.		yyerror("syntax error near \"%c\"\n", yytext[0]);
596 
597 <S1>"/*"	yyerror("/* encountered inside a comment\n");
598 <S1>"*/"	BEGIN(yypcb->pcb_cstate);
599 <S1>.|\n	; /* discard */
600 
601 <S2>{RGX_PSPEC}	{
602 			/*
603 			 * S2 has an ambiguity because RGX_PSPEC includes '*'
604 			 * as a glob character and '*' also can be DT_TOK_STAR.
605 			 * Since lex always matches the longest token, this
606 			 * rule can be matched by an input string like "int*",
607 			 * which could begin a global variable declaration such
608 			 * as "int*x;" or could begin a RGX_PSPEC with globbing
609 			 * such as "int* { trace(timestamp); }".  If C_PSPEC is
610 			 * not set, we must resolve the ambiguity in favor of
611 			 * the type and perform lexer pushback if the fragment
612 			 * before '*' or entire fragment matches a type name.
613 			 * If C_PSPEC is set, we always return a PSPEC token.
614 			 * If C_PSPEC is off, the user can avoid ambiguity by
615 			 * including a ':' delimiter in the specifier, which
616 			 * they should be doing anyway to specify the provider.
617 			 */
618 			if (!(yypcb->pcb_cflags & DTRACE_C_PSPEC) &&
619 			    strchr(yytext, ':') == NULL) {
620 
621 				char *p = strchr(yytext, '*');
622 				char *q = yytext + yyleng - 1;
623 
624 				if (p != NULL && p > yytext)
625 					*p = '\0'; /* prune yytext */
626 
627 				if (dt_type_lookup(yytext, NULL) == 0) {
628 					yylval.l_str = strdup(yytext);
629 
630 					if (yylval.l_str == NULL) {
631 						longjmp(yypcb->pcb_jmpbuf,
632 						    EDT_NOMEM);
633 					}
634 
635 					if (p != NULL && p > yytext) {
636 						for (*p = '*'; q >= p; q--)
637 							unput(*q);
638 					}
639 
640 					yybegin(YYS_EXPR);
641 					return (DT_TOK_TNAME);
642 				}
643 
644 				if (p != NULL && p > yytext)
645 					*p = '*'; /* restore yytext */
646 			}
647 
648 			if ((yylval.l_str = strdup(yytext)) == NULL)
649 				longjmp(yypcb->pcb_jmpbuf, EDT_NOMEM);
650 
651 			return (DT_TOK_PSPEC);
652 		}
653 
654 <S2>"/"		return (DT_TOK_DIV);
655 <S2>","		return (DT_TOK_COMMA);
656 
657 <S2>{RGX_WS}	; /* discard */
658 <S2>.		yyerror("syntax error near \"%c\"\n", yytext[0]);
659 
660 <S3>\n		{
661 			dt_pragma(yypragma);
662 			yypragma = NULL;
663 			BEGIN(yypcb->pcb_cstate);
664 		}
665 
666 <S3>[\f\t\v ]+	; /* discard */
667 
668 <S3>[^\f\n\t\v "]+ {
669 			dt_node_t *dnp;
670 
671 			if ((yylval.l_str = strdup(yytext)) == NULL)
672 				longjmp(yypcb->pcb_jmpbuf, EDT_NOMEM);
673 
674 			/*
675 			 * We want to call dt_node_ident() here, but we can't
676 			 * because it will expand inlined identifiers, which we
677 			 * don't want to do from #pragma context in order to
678 			 * support pragmas that apply to the ident itself.  We
679 			 * call dt_node_string() and then reset dn_op instead.
680 			 */
681 			dnp = dt_node_string(yylval.l_str);
682 			dnp->dn_kind = DT_NODE_IDENT;
683 			dnp->dn_op = DT_TOK_IDENT;
684 			yypragma = dt_node_link(yypragma, dnp);
685 		}
686 
687 <S3>.		yyerror("syntax error near \"%c\"\n", yytext[0]);
688 
689 %%
690 
691 /*
692  * yybegin provides a wrapper for use from C code around the lex BEGIN() macro.
693  * We use two main states for lexing because probe descriptions use a syntax
694  * that is incompatible with the normal D tokens (e.g. names can contain "-").
695  * yybegin also handles the job of switching between two lists of dt_nodes
696  * as we allocate persistent definitions, like inlines, and transient nodes
697  * that will be freed once we are done parsing the current program file.
698  */
699 void
700 yybegin(yystate_t state)
701 {
702 #ifdef	YYDEBUG
703 	yydebug = _dtrace_debug;
704 #endif
705 	if (yypcb->pcb_yystate == state)
706 		return; /* nothing to do if we're in the state already */
707 
708 	if (yypcb->pcb_yystate == YYS_DEFINE) {
709 		yypcb->pcb_list = yypcb->pcb_hold;
710 		yypcb->pcb_hold = NULL;
711 	}
712 
713 	switch (state) {
714 	case YYS_CLAUSE:
715 		BEGIN(S2);
716 		break;
717 	case YYS_DEFINE:
718 		assert(yypcb->pcb_hold == NULL);
719 		yypcb->pcb_hold = yypcb->pcb_list;
720 		yypcb->pcb_list = NULL;
721 		/*FALLTHRU*/
722 	case YYS_EXPR:
723 		BEGIN(S0);
724 		break;
725 	case YYS_DONE:
726 		break;
727 	case YYS_CONTROL:
728 		BEGIN(S4);
729 		break;
730 	default:
731 		xyerror(D_UNKNOWN, "internal error -- bad yystate %d\n", state);
732 	}
733 
734 	yypcb->pcb_yystate = state;
735 }
736 
737 void
738 yyinit(dt_pcb_t *pcb)
739 {
740 	yypcb = pcb;
741 	yylineno = 1;
742 	yypragma = NULL;
743 #if defined(sun)
744 	yysptr = yysbuf;
745 #endif
746 }
747 
748 /*
749  * Given a lexeme 's' (typically yytext), set yylval and return an appropriate
750  * token to the parser indicating either an identifier or a typedef name.
751  * User-defined global variables always take precedence over types, but we do
752  * use some heuristics because D programs can look at an ever-changing set of
753  * kernel types and also can implicitly instantiate variables by assignment,
754  * unlike in C.  The code here is ordered carefully as lookups are not cheap.
755  */
756 static int
757 id_or_type(const char *s)
758 {
759 	dtrace_hdl_t *dtp = yypcb->pcb_hdl;
760 	dt_decl_t *ddp = yypcb->pcb_dstack.ds_decl;
761 	int c0, c1, ttok = DT_TOK_TNAME;
762 	dt_ident_t *idp;
763 
764 	if ((s = yylval.l_str = strdup(s)) == NULL)
765 		longjmp(yypcb->pcb_jmpbuf, EDT_NOMEM);
766 
767 	/*
768 	 * If the lexeme is a global variable or likely identifier or *not* a
769 	 * type_name, then it is an identifier token.
770 	 */
771 	if (dt_idstack_lookup(&yypcb->pcb_globals, s) != NULL ||
772 	    dt_idhash_lookup(yypcb->pcb_idents, s) != NULL ||
773 	    dt_type_lookup(s, NULL) != 0)
774 		return (DT_TOK_IDENT);
775 
776 	/*
777 	 * If we're in the midst of parsing a declaration and a type_specifier
778 	 * has already been shifted, then return DT_TOK_IDENT instead of TNAME.
779 	 * This semantic is necessary to permit valid ISO C code such as:
780 	 *
781 	 * typedef int foo;
782 	 * struct s { foo foo; };
783 	 *
784 	 * without causing shift/reduce conflicts in the direct_declarator part
785 	 * of the grammar.  The result is that we must check for conflicting
786 	 * redeclarations of the same identifier as part of dt_node_decl().
787 	 */
788 	if (ddp != NULL && ddp->dd_name != NULL)
789 		return (DT_TOK_IDENT);
790 
791 	/*
792 	 * If the lexeme is a type name and we are not in a program clause,
793 	 * then always interpret it as a type and return DT_TOK_TNAME.
794 	 */
795 	if ((YYSTATE) != S0)
796 		return (DT_TOK_TNAME);
797 
798 	/*
799 	 * If the lexeme matches a type name but is in a program clause, then
800 	 * it could be a type or it could be an undefined variable.  Peek at
801 	 * the next token to decide.  If we see ++, --, [, or =, we know there
802 	 * might be an assignment that is trying to create a global variable,
803 	 * so we optimistically return DT_TOK_IDENT.  There is no harm in being
804 	 * wrong: a type_name followed by ++, --, [, or = is a syntax error.
805 	 */
806 	while ((c0 = input()) != 0) {
807 		if (strchr("\f\n\r\t\v ", c0) == NULL)
808 			break;
809 	}
810 
811 	switch (c0) {
812 	case '+':
813 	case '-':
814 		if ((c1 = input()) == c0)
815 			ttok = DT_TOK_IDENT;
816 		unput(c1);
817 		break;
818 
819 	case '=':
820 		if ((c1 = input()) != c0)
821 			ttok = DT_TOK_IDENT;
822 		unput(c1);
823 		break;
824 	case '[':
825 		ttok = DT_TOK_IDENT;
826 		break;
827 	}
828 
829 	if (ttok == DT_TOK_IDENT) {
830 		idp = dt_idhash_insert(yypcb->pcb_idents, s, DT_IDENT_SCALAR, 0,
831 		    0, _dtrace_defattr, 0, &dt_idops_thaw, NULL, dtp->dt_gen);
832 
833 		if (idp == NULL)
834 			longjmp(yypcb->pcb_jmpbuf, EDT_NOMEM);
835 	}
836 
837 	unput(c0);
838 	return (ttok);
839 }
840 
841 #if defined(sun)
842 static int
843 input(void)
844 {
845 	int c;
846 
847 	if (yysptr > yysbuf)
848 		c = *--yysptr;
849 	else if (yypcb->pcb_fileptr != NULL)
850 		c = fgetc(yypcb->pcb_fileptr);
851 	else if (yypcb->pcb_strptr < yypcb->pcb_string + yypcb->pcb_strlen)
852 		c = *(unsigned char *)(yypcb->pcb_strptr++);
853 	else
854 		c = EOF;
855 
856 	if (c == '\n')
857 		yylineno++;
858 
859 	if (c != EOF)
860 		return (c);
861 
862 	if ((YYSTATE) == S1)
863 		yyerror("end-of-file encountered before matching */\n");
864 
865 	if ((YYSTATE) == S3)
866 		yyerror("end-of-file encountered before end of control line\n");
867 
868 	if (yypcb->pcb_fileptr != NULL && ferror(yypcb->pcb_fileptr))
869 		longjmp(yypcb->pcb_jmpbuf, EDT_FIO);
870 
871 	return (0); /* EOF */
872 }
873 
874 static void
875 unput(int c)
876 {
877 	if (c == '\n')
878 		yylineno--;
879 
880 	*yysptr++ = c;
881 	yytchar = c;
882 }
883 #endif
884