xref: /linux/scripts/genksyms/parse.y (revision 52338415) 
1 /* SPDX-License-Identifier: GPL-2.0-or-later */
2 /*
3  * C global declaration parser for genksyms.
4  * Copyright 1996, 1997 Linux International.
5  *
6  * New implementation contributed by Richard Henderson <rth@tamu.edu>
7  * Based on original work by Bjorn Ekwall <bj0rn@blox.se>
8  *
9  * This file is part of the Linux modutils.
10  */
11 
12 %{
13 
14 #include <assert.h>
15 #include <stdlib.h>
16 #include <string.h>
17 #include "genksyms.h"
18 
19 static int is_typedef;
20 static int is_extern;
21 static char *current_name;
22 static struct string_list *decl_spec;
23 
24 static void yyerror(const char *);
25 
26 static inline void
27 remove_node(struct string_list **p)
28 {
29   struct string_list *node = *p;
30   *p = node->next;
31   free_node(node);
32 }
33 
34 static inline void
35 remove_list(struct string_list **pb, struct string_list **pe)
36 {
37   struct string_list *b = *pb, *e = *pe;
38   *pb = e;
39   free_list(b, e);
40 }
41 
42 /* Record definition of a struct/union/enum */
43 static void record_compound(struct string_list **keyw,
44 		       struct string_list **ident,
45 		       struct string_list **body,
46 		       enum symbol_type type)
47 {
48 	struct string_list *b = *body, *i = *ident, *r;
49 
50 	if (i->in_source_file) {
51 		remove_node(keyw);
52 		(*ident)->tag = type;
53 		remove_list(body, ident);
54 		return;
55 	}
56 	r = copy_node(i); r->tag = type;
57 	r->next = (*keyw)->next; *body = r; (*keyw)->next = NULL;
58 	add_symbol(i->string, type, b, is_extern);
59 }
60 
61 %}
62 
63 %token ASM_KEYW
64 %token ATTRIBUTE_KEYW
65 %token AUTO_KEYW
66 %token BOOL_KEYW
67 %token BUILTIN_INT_KEYW
68 %token CHAR_KEYW
69 %token CONST_KEYW
70 %token DOUBLE_KEYW
71 %token ENUM_KEYW
72 %token EXTERN_KEYW
73 %token EXTENSION_KEYW
74 %token FLOAT_KEYW
75 %token INLINE_KEYW
76 %token INT_KEYW
77 %token LONG_KEYW
78 %token REGISTER_KEYW
79 %token RESTRICT_KEYW
80 %token SHORT_KEYW
81 %token SIGNED_KEYW
82 %token STATIC_KEYW
83 %token STRUCT_KEYW
84 %token TYPEDEF_KEYW
85 %token UNION_KEYW
86 %token UNSIGNED_KEYW
87 %token VOID_KEYW
88 %token VOLATILE_KEYW
89 %token TYPEOF_KEYW
90 %token VA_LIST_KEYW
91 
92 %token EXPORT_SYMBOL_KEYW
93 
94 %token ASM_PHRASE
95 %token ATTRIBUTE_PHRASE
96 %token TYPEOF_PHRASE
97 %token BRACE_PHRASE
98 %token BRACKET_PHRASE
99 %token EXPRESSION_PHRASE
100 
101 %token CHAR
102 %token DOTS
103 %token IDENT
104 %token INT
105 %token REAL
106 %token STRING
107 %token TYPE
108 %token OTHER
109 %token FILENAME
110 
111 %%
112 
113 declaration_seq:
114 	declaration
115 	| declaration_seq declaration
116 	;
117 
118 declaration:
119 	{ is_typedef = 0; is_extern = 0; current_name = NULL; decl_spec = NULL; }
120 	declaration1
121 	{ free_list(*$2, NULL); *$2 = NULL; }
122 	;
123 
124 declaration1:
125 	EXTENSION_KEYW TYPEDEF_KEYW { is_typedef = 1; } simple_declaration
126 		{ $$ = $4; }
127 	| TYPEDEF_KEYW { is_typedef = 1; } simple_declaration
128 		{ $$ = $3; }
129 	| simple_declaration
130 	| function_definition
131 	| asm_definition
132 	| export_definition
133 	| error ';'				{ $$ = $2; }
134 	| error '}'				{ $$ = $2; }
135 	;
136 
137 simple_declaration:
138 	decl_specifier_seq_opt init_declarator_list_opt ';'
139 		{ if (current_name) {
140 		    struct string_list *decl = (*$3)->next;
141 		    (*$3)->next = NULL;
142 		    add_symbol(current_name,
143 			       is_typedef ? SYM_TYPEDEF : SYM_NORMAL,
144 			       decl, is_extern);
145 		    current_name = NULL;
146 		  }
147 		  $$ = $3;
148 		}
149 	;
150 
151 init_declarator_list_opt:
152 	/* empty */				{ $$ = NULL; }
153 	| init_declarator_list
154 	;
155 
156 init_declarator_list:
157 	init_declarator
158 		{ struct string_list *decl = *$1;
159 		  *$1 = NULL;
160 		  add_symbol(current_name,
161 			     is_typedef ? SYM_TYPEDEF : SYM_NORMAL, decl, is_extern);
162 		  current_name = NULL;
163 		  $$ = $1;
164 		}
165 	| init_declarator_list ',' init_declarator
166 		{ struct string_list *decl = *$3;
167 		  *$3 = NULL;
168 		  free_list(*$2, NULL);
169 		  *$2 = decl_spec;
170 		  add_symbol(current_name,
171 			     is_typedef ? SYM_TYPEDEF : SYM_NORMAL, decl, is_extern);
172 		  current_name = NULL;
173 		  $$ = $3;
174 		}
175 	;
176 
177 init_declarator:
178 	declarator asm_phrase_opt attribute_opt initializer_opt
179 		{ $$ = $4 ? $4 : $3 ? $3 : $2 ? $2 : $1; }
180 	;
181 
182 /* Hang on to the specifiers so that we can reuse them.  */
183 decl_specifier_seq_opt:
184 	/* empty */				{ decl_spec = NULL; }
185 	| decl_specifier_seq
186 	;
187 
188 decl_specifier_seq:
189 	decl_specifier				{ decl_spec = *$1; }
190 	| decl_specifier_seq decl_specifier	{ decl_spec = *$2; }
191 	;
192 
193 decl_specifier:
194 	storage_class_specifier
195 		{ /* Version 2 checksumming ignores storage class, as that
196 		     is really irrelevant to the linkage.  */
197 		  remove_node($1);
198 		  $$ = $1;
199 		}
200 	| type_specifier
201 	;
202 
203 storage_class_specifier:
204 	AUTO_KEYW
205 	| REGISTER_KEYW
206 	| STATIC_KEYW
207 	| EXTERN_KEYW	{ is_extern = 1; $$ = $1; }
208 	| INLINE_KEYW	{ is_extern = 0; $$ = $1; }
209 	;
210 
211 type_specifier:
212 	simple_type_specifier
213 	| cvar_qualifier
214 	| TYPEOF_KEYW '(' parameter_declaration ')'
215 	| TYPEOF_PHRASE
216 
217 	/* References to s/u/e's defined elsewhere.  Rearrange things
218 	   so that it is easier to expand the definition fully later.  */
219 	| STRUCT_KEYW IDENT
220 		{ remove_node($1); (*$2)->tag = SYM_STRUCT; $$ = $2; }
221 	| UNION_KEYW IDENT
222 		{ remove_node($1); (*$2)->tag = SYM_UNION; $$ = $2; }
223 	| ENUM_KEYW IDENT
224 		{ remove_node($1); (*$2)->tag = SYM_ENUM; $$ = $2; }
225 
226 	/* Full definitions of an s/u/e.  Record it.  */
227 	| STRUCT_KEYW IDENT class_body
228 		{ record_compound($1, $2, $3, SYM_STRUCT); $$ = $3; }
229 	| UNION_KEYW IDENT class_body
230 		{ record_compound($1, $2, $3, SYM_UNION); $$ = $3; }
231 	| ENUM_KEYW IDENT enum_body
232 		{ record_compound($1, $2, $3, SYM_ENUM); $$ = $3; }
233 	/*
234 	 * Anonymous enum definition. Tell add_symbol() to restart its counter.
235 	 */
236 	| ENUM_KEYW enum_body
237 		{ add_symbol(NULL, SYM_ENUM, NULL, 0); $$ = $2; }
238 	/* Anonymous s/u definitions.  Nothing needs doing.  */
239 	| STRUCT_KEYW class_body			{ $$ = $2; }
240 	| UNION_KEYW class_body				{ $$ = $2; }
241 	;
242 
243 simple_type_specifier:
244 	CHAR_KEYW
245 	| SHORT_KEYW
246 	| INT_KEYW
247 	| LONG_KEYW
248 	| SIGNED_KEYW
249 	| UNSIGNED_KEYW
250 	| FLOAT_KEYW
251 	| DOUBLE_KEYW
252 	| VOID_KEYW
253 	| BOOL_KEYW
254 	| VA_LIST_KEYW
255 	| BUILTIN_INT_KEYW
256 	| TYPE			{ (*$1)->tag = SYM_TYPEDEF; $$ = $1; }
257 	;
258 
259 ptr_operator:
260 	'*' cvar_qualifier_seq_opt
261 		{ $$ = $2 ? $2 : $1; }
262 	;
263 
264 cvar_qualifier_seq_opt:
265 	/* empty */					{ $$ = NULL; }
266 	| cvar_qualifier_seq
267 	;
268 
269 cvar_qualifier_seq:
270 	cvar_qualifier
271 	| cvar_qualifier_seq cvar_qualifier		{ $$ = $2; }
272 	;
273 
274 cvar_qualifier:
275 	CONST_KEYW | VOLATILE_KEYW | ATTRIBUTE_PHRASE
276 	| RESTRICT_KEYW
277 		{ /* restrict has no effect in prototypes so ignore it */
278 		  remove_node($1);
279 		  $$ = $1;
280 		}
281 	;
282 
283 declarator:
284 	ptr_operator declarator			{ $$ = $2; }
285 	| direct_declarator
286 	;
287 
288 direct_declarator:
289 	IDENT
290 		{ if (current_name != NULL) {
291 		    error_with_pos("unexpected second declaration name");
292 		    YYERROR;
293 		  } else {
294 		    current_name = (*$1)->string;
295 		    $$ = $1;
296 		  }
297 		}
298 	| TYPE
299 		{ if (current_name != NULL) {
300 		    error_with_pos("unexpected second declaration name");
301 		    YYERROR;
302 		  } else {
303 		    current_name = (*$1)->string;
304 		    $$ = $1;
305 		  }
306 		}
307 	| direct_declarator '(' parameter_declaration_clause ')'
308 		{ $$ = $4; }
309 	| direct_declarator '(' error ')'
310 		{ $$ = $4; }
311 	| direct_declarator BRACKET_PHRASE
312 		{ $$ = $2; }
313 	| '(' declarator ')'
314 		{ $$ = $3; }
315 	;
316 
317 /* Nested declarators differ from regular declarators in that they do
318    not record the symbols they find in the global symbol table.  */
319 nested_declarator:
320 	ptr_operator nested_declarator		{ $$ = $2; }
321 	| direct_nested_declarator
322 	;
323 
324 direct_nested_declarator:
325 	IDENT
326 	| TYPE
327 	| direct_nested_declarator '(' parameter_declaration_clause ')'
328 		{ $$ = $4; }
329 	| direct_nested_declarator '(' error ')'
330 		{ $$ = $4; }
331 	| direct_nested_declarator BRACKET_PHRASE
332 		{ $$ = $2; }
333 	| '(' nested_declarator ')'
334 		{ $$ = $3; }
335 	| '(' error ')'
336 		{ $$ = $3; }
337 	;
338 
339 parameter_declaration_clause:
340 	parameter_declaration_list_opt DOTS		{ $$ = $2; }
341 	| parameter_declaration_list_opt
342 	| parameter_declaration_list ',' DOTS		{ $$ = $3; }
343 	;
344 
345 parameter_declaration_list_opt:
346 	/* empty */					{ $$ = NULL; }
347 	| parameter_declaration_list
348 	;
349 
350 parameter_declaration_list:
351 	parameter_declaration
352 	| parameter_declaration_list ',' parameter_declaration
353 		{ $$ = $3; }
354 	;
355 
356 parameter_declaration:
357 	decl_specifier_seq m_abstract_declarator
358 		{ $$ = $2 ? $2 : $1; }
359 	;
360 
361 m_abstract_declarator:
362 	ptr_operator m_abstract_declarator
363 		{ $$ = $2 ? $2 : $1; }
364 	| direct_m_abstract_declarator
365 	;
366 
367 direct_m_abstract_declarator:
368 	/* empty */					{ $$ = NULL; }
369 	| IDENT
370 		{ /* For version 2 checksums, we don't want to remember
371 		     private parameter names.  */
372 		  remove_node($1);
373 		  $$ = $1;
374 		}
375 	/* This wasn't really a typedef name but an identifier that
376 	   shadows one.  */
377 	| TYPE
378 		{ remove_node($1);
379 		  $$ = $1;
380 		}
381 	| direct_m_abstract_declarator '(' parameter_declaration_clause ')'
382 		{ $$ = $4; }
383 	| direct_m_abstract_declarator '(' error ')'
384 		{ $$ = $4; }
385 	| direct_m_abstract_declarator BRACKET_PHRASE
386 		{ $$ = $2; }
387 	| '(' m_abstract_declarator ')'
388 		{ $$ = $3; }
389 	| '(' error ')'
390 		{ $$ = $3; }
391 	;
392 
393 function_definition:
394 	decl_specifier_seq_opt declarator BRACE_PHRASE
395 		{ struct string_list *decl = *$2;
396 		  *$2 = NULL;
397 		  add_symbol(current_name, SYM_NORMAL, decl, is_extern);
398 		  $$ = $3;
399 		}
400 	;
401 
402 initializer_opt:
403 	/* empty */					{ $$ = NULL; }
404 	| initializer
405 	;
406 
407 /* We never care about the contents of an initializer.  */
408 initializer:
409 	'=' EXPRESSION_PHRASE
410 		{ remove_list($2, &(*$1)->next); $$ = $2; }
411 	;
412 
413 class_body:
414 	'{' member_specification_opt '}'		{ $$ = $3; }
415 	| '{' error '}'					{ $$ = $3; }
416 	;
417 
418 member_specification_opt:
419 	/* empty */					{ $$ = NULL; }
420 	| member_specification
421 	;
422 
423 member_specification:
424 	member_declaration
425 	| member_specification member_declaration	{ $$ = $2; }
426 	;
427 
428 member_declaration:
429 	decl_specifier_seq_opt member_declarator_list_opt ';'
430 		{ $$ = $3; }
431 	| error ';'
432 		{ $$ = $2; }
433 	;
434 
435 member_declarator_list_opt:
436 	/* empty */					{ $$ = NULL; }
437 	| member_declarator_list
438 	;
439 
440 member_declarator_list:
441 	member_declarator
442 	| member_declarator_list ',' member_declarator	{ $$ = $3; }
443 	;
444 
445 member_declarator:
446 	nested_declarator attribute_opt			{ $$ = $2 ? $2 : $1; }
447 	| IDENT member_bitfield_declarator		{ $$ = $2; }
448 	| member_bitfield_declarator
449 	;
450 
451 member_bitfield_declarator:
452 	':' EXPRESSION_PHRASE				{ $$ = $2; }
453 	;
454 
455 attribute_opt:
456 	/* empty */					{ $$ = NULL; }
457 	| attribute_opt ATTRIBUTE_PHRASE
458 	;
459 
460 enum_body:
461 	'{' enumerator_list '}'				{ $$ = $3; }
462 	| '{' enumerator_list ',' '}'			{ $$ = $4; }
463 	 ;
464 
465 enumerator_list:
466 	enumerator
467 	| enumerator_list ',' enumerator
468 
469 enumerator:
470 	IDENT
471 		{
472 			const char *name = strdup((*$1)->string);
473 			add_symbol(name, SYM_ENUM_CONST, NULL, 0);
474 		}
475 	| IDENT '=' EXPRESSION_PHRASE
476 		{
477 			const char *name = strdup((*$1)->string);
478 			struct string_list *expr = copy_list_range(*$3, *$2);
479 			add_symbol(name, SYM_ENUM_CONST, expr, 0);
480 		}
481 
482 asm_definition:
483 	ASM_PHRASE ';'					{ $$ = $2; }
484 	;
485 
486 asm_phrase_opt:
487 	/* empty */					{ $$ = NULL; }
488 	| ASM_PHRASE
489 	;
490 
491 export_definition:
492 	EXPORT_SYMBOL_KEYW '(' IDENT ')' ';'
493 		{ export_symbol((*$3)->string); $$ = $5; }
494 	;
495 
496 
497 %%
498 
499 static void
500 yyerror(const char *e)
501 {
502   error_with_pos("%s", e);
503 }
504