kernel/scripts/genksyms/parse.y

   1 /* C global declaration parser for genksyms.
   2    Copyright 1996, 1997 Linux International.
   3
   4    New implementation contributed by Richard Henderson <rth@tamu.edu>
   5    Based on original work by Bjorn Ekwall <bj0rn@blox.se>
   6
   7    This file is part of the Linux modutils.
   8
   9    This program is free software; you can redistribute it and/or modify it
  10    under the terms of the GNU General Public License as published by the
  11    Free Software Foundation; either version 2 of the License, or (at your
  12    option) any later version.
  13
  14    This program is distributed in the hope that it will be useful, but
  15    WITHOUT ANY WARRANTY; without even the implied warranty of
  16    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  17    General Public License for more details.
  18
  19    You should have received a copy of the GNU General Public License
  20    along with this program; if not, write to the Free Software Foundation,
  21    Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.  */
  22
  23
  24 %{
  25
  26 #include <assert.h>
  27 #include <stdlib.h>
  28 #include <string.h>
  29 #include "genksyms.h"
  30
  31 static int is_typedef;
  32 static int is_extern;
  33 static char *current_name;
  34 static struct string_list *decl_spec;
  35
  36 static void yyerror(const char *);
  37
  38 static inline void
  39 remove_node(struct string_list **p)
  40 {
  41   struct string_list *node = *p;
  42   *p = node->next;
  43   free_node(node);
  44 }
  45
  46 static inline void
  47 remove_list(struct string_list **pb, struct string_list **pe)
  48 {
  49   struct string_list *b = *pb, *e = *pe;
  50   *pb = e;
  51   free_list(b, e);
  52 }
  53
  54 /* Record definition of a struct/union/enum */
  55 static void record_compound(struct string_list **keyw,
  56                        struct string_list **ident,
  57                        struct string_list **body,
  58                        enum symbol_type type)
  59 {
  60         struct string_list *b = *body, *i = *ident, *r;
  61
  62         if (i->in_source_file) {
  63                 remove_node(keyw);
  64                 (*ident)->tag = type;
  65                 remove_list(body, ident);
  66                 return;
  67         }
  68         r = copy_node(i); r->tag = type;
  69         r->next = (*keyw)->next; *body = r; (*keyw)->next = NULL;
  70         add_symbol(i->string, type, b, is_extern);
  71 }
  72
  73 %}
  74
  75 %token ASM_KEYW
  76 %token ATTRIBUTE_KEYW
  77 %token AUTO_KEYW
  78 %token BOOL_KEYW
  79 %token CHAR_KEYW
  80 %token CONST_KEYW
  81 %token DOUBLE_KEYW
  82 %token ENUM_KEYW
  83 %token EXTERN_KEYW
  84 %token EXTENSION_KEYW
  85 %token FLOAT_KEYW
  86 %token INLINE_KEYW
  87 %token INT_KEYW
  88 %token LONG_KEYW
  89 %token REGISTER_KEYW
  90 %token RESTRICT_KEYW
  91 %token SHORT_KEYW
  92 %token SIGNED_KEYW
  93 %token STATIC_KEYW
  94 %token STRUCT_KEYW
  95 %token TYPEDEF_KEYW
  96 %token UNION_KEYW
  97 %token UNSIGNED_KEYW
  98 %token VOID_KEYW
  99 %token VOLATILE_KEYW
 100 %token TYPEOF_KEYW
 101
 102 %token EXPORT_SYMBOL_KEYW
 103
 104 %token ASM_PHRASE
 105 %token ATTRIBUTE_PHRASE
 106 %token TYPEOF_PHRASE
 107 %token BRACE_PHRASE
 108 %token BRACKET_PHRASE
 109 %token EXPRESSION_PHRASE
 110
 111 %token CHAR
 112 %token DOTS
 113 %token IDENT
 114 %token INT
 115 %token REAL
 116 %token STRING
 117 %token TYPE
 118 %token OTHER
 119 %token FILENAME
 120
 121 %%
 122
 123 declaration_seq:
 124         declaration
 125         | declaration_seq declaration
 126         ;
 127
 128 declaration:
 129         { is_typedef = 0; is_extern = 0; current_name = NULL; decl_spec = NULL; }
 130         declaration1
 131         { free_list(*$2, NULL); *$2 = NULL; }
 132         ;
 133
 134 declaration1:
 135         EXTENSION_KEYW TYPEDEF_KEYW { is_typedef = 1; } simple_declaration
 136                 { $$ = $4; }
 137         | TYPEDEF_KEYW { is_typedef = 1; } simple_declaration
 138                 { $$ = $3; }
 139         | simple_declaration
 140         | function_definition
 141         | asm_definition
 142         | export_definition
 143         | error ';'                             { $$ = $2; }
 144         | error '}'                             { $$ = $2; }
 145         ;
 146
 147 simple_declaration:
 148         decl_specifier_seq_opt init_declarator_list_opt ';'
 149                 { if (current_name) {
 150                     struct string_list *decl = (*$3)->next;
 151                     (*$3)->next = NULL;
 152                     add_symbol(current_name,
 153                                is_typedef ? SYM_TYPEDEF : SYM_NORMAL,
 154                                decl, is_extern);
 155                     current_name = NULL;
 156                   }
 157                   $$ = $3;
 158                 }
 159         ;
 160
 161 init_declarator_list_opt:
 162         /* empty */                             { $$ = NULL; }
 163         | init_declarator_list
 164         ;
 165
 166 init_declarator_list:
 167         init_declarator
 168                 { struct string_list *decl = *$1;
 169                   *$1 = NULL;
 170                   add_symbol(current_name,
 171                              is_typedef ? SYM_TYPEDEF : SYM_NORMAL, decl, is_extern);
 172                   current_name = NULL;
 173                   $$ = $1;
 174                 }
 175         | init_declarator_list ',' init_declarator
 176                 { struct string_list *decl = *$3;
 177                   *$3 = NULL;
 178                   free_list(*$2, NULL);
 179                   *$2 = decl_spec;
 180                   add_symbol(current_name,
 181                              is_typedef ? SYM_TYPEDEF : SYM_NORMAL, decl, is_extern);
 182                   current_name = NULL;
 183                   $$ = $3;
 184                 }
 185         ;
 186
 187 init_declarator:
 188         declarator asm_phrase_opt attribute_opt initializer_opt
 189                 { $$ = $4 ? $4 : $3 ? $3 : $2 ? $2 : $1; }
 190         ;
 191
 192 /* Hang on to the specifiers so that we can reuse them.  */
 193 decl_specifier_seq_opt:
 194         /* empty */                             { decl_spec = NULL; }
 195         | decl_specifier_seq
 196         ;
 197
 198 decl_specifier_seq:
 199         decl_specifier                          { decl_spec = *$1; }
 200         | decl_specifier_seq decl_specifier     { decl_spec = *$2; }
 201         ;
 202
 203 decl_specifier:
 204         storage_class_specifier
 205                 { /* Version 2 checksumming ignores storage class, as that
 206                      is really irrelevant to the linkage.  */
 207                   remove_node($1);
 208                   $$ = $1;
 209                 }
 210         | type_specifier
 211         ;
 212
 213 storage_class_specifier:
 214         AUTO_KEYW
 215         | REGISTER_KEYW
 216         | STATIC_KEYW
 217         | EXTERN_KEYW   { is_extern = 1; $$ = $1; }
 218         | INLINE_KEYW   { is_extern = 0; $$ = $1; }
 219         ;
 220
 221 type_specifier:
 222         simple_type_specifier
 223         | cvar_qualifier
 224         | TYPEOF_KEYW '(' parameter_declaration ')'
 225         | TYPEOF_PHRASE
 226
 227         /* References to s/u/e's defined elsewhere.  Rearrange things
 228            so that it is easier to expand the definition fully later.  */
 229         | STRUCT_KEYW IDENT
 230                 { remove_node($1); (*$2)->tag = SYM_STRUCT; $$ = $2; }
 231         | UNION_KEYW IDENT
 232                 { remove_node($1); (*$2)->tag = SYM_UNION; $$ = $2; }
 233         | ENUM_KEYW IDENT
 234                 { remove_node($1); (*$2)->tag = SYM_ENUM; $$ = $2; }
 235
 236         /* Full definitions of an s/u/e.  Record it.  */
 237         | STRUCT_KEYW IDENT class_body
 238                 { record_compound($1, $2, $3, SYM_STRUCT); $$ = $3; }
 239         | UNION_KEYW IDENT class_body
 240                 { record_compound($1, $2, $3, SYM_UNION); $$ = $3; }
 241         | ENUM_KEYW IDENT enum_body
 242                 { record_compound($1, $2, $3, SYM_ENUM); $$ = $3; }
 243         /*
 244          * Anonymous enum definition. Tell add_symbol() to restart its counter.
 245          */
 246         | ENUM_KEYW enum_body
 247                 { add_symbol(NULL, SYM_ENUM, NULL, 0); $$ = $2; }
 248         /* Anonymous s/u definitions.  Nothing needs doing.  */
 249         | STRUCT_KEYW class_body                        { $$ = $2; }
 250         | UNION_KEYW class_body                         { $$ = $2; }
 251         ;
 252
 253 simple_type_specifier:
 254         CHAR_KEYW
 255         | SHORT_KEYW
 256         | INT_KEYW
 257         | LONG_KEYW
 258         | SIGNED_KEYW
 259         | UNSIGNED_KEYW
 260         | FLOAT_KEYW
 261         | DOUBLE_KEYW
 262         | VOID_KEYW
 263         | BOOL_KEYW
 264         | TYPE                  { (*$1)->tag = SYM_TYPEDEF; $$ = $1; }
 265         ;
 266
 267 ptr_operator:
 268         '*' cvar_qualifier_seq_opt
 269                 { $$ = $2 ? $2 : $1; }
 270         ;
 271
 272 cvar_qualifier_seq_opt:
 273         /* empty */                                     { $$ = NULL; }
 274         | cvar_qualifier_seq
 275         ;
 276
 277 cvar_qualifier_seq:
 278         cvar_qualifier
 279         | cvar_qualifier_seq cvar_qualifier             { $$ = $2; }
 280         ;
 281
 282 cvar_qualifier:
 283         CONST_KEYW | VOLATILE_KEYW | ATTRIBUTE_PHRASE
 284         | RESTRICT_KEYW
 285                 { /* restrict has no effect in prototypes so ignore it */
 286                   remove_node($1);
 287                   $$ = $1;
 288                 }
 289         ;
 290
 291 declarator:
 292         ptr_operator declarator                 { $$ = $2; }
 293         | direct_declarator
 294         ;
 295
 296 direct_declarator:
 297         IDENT
 298                 { if (current_name != NULL) {
 299                     error_with_pos("unexpected second declaration name");
 300                     YYERROR;
 301                   } else {
 302                     current_name = (*$1)->string;
 303                     $$ = $1;
 304                   }
 305                 }
 306         | direct_declarator '(' parameter_declaration_clause ')'
 307                 { $$ = $4; }
 308         | direct_declarator '(' error ')'
 309                 { $$ = $4; }
 310         | direct_declarator BRACKET_PHRASE
 311                 { $$ = $2; }
 312         | '(' declarator ')'
 313                 { $$ = $3; }
 314         | '(' error ')'
 315                 { $$ = $3; }
 316         ;
 317
 318 /* Nested declarators differ from regular declarators in that they do
 319    not record the symbols they find in the global symbol table.  */
 320 nested_declarator:
 321         ptr_operator nested_declarator          { $$ = $2; }
 322         | direct_nested_declarator
 323         ;
 324
 325 direct_nested_declarator:
 326         IDENT
 327         | TYPE
 328         | direct_nested_declarator '(' parameter_declaration_clause ')'
 329                 { $$ = $4; }
 330         | direct_nested_declarator '(' error ')'
 331                 { $$ = $4; }
 332         | direct_nested_declarator BRACKET_PHRASE
 333                 { $$ = $2; }
 334         | '(' nested_declarator ')'
 335                 { $$ = $3; }
 336         | '(' error ')'
 337                 { $$ = $3; }
 338         ;
 339
 340 parameter_declaration_clause:
 341         parameter_declaration_list_opt DOTS             { $$ = $2; }
 342         | parameter_declaration_list_opt
 343         | parameter_declaration_list ',' DOTS           { $$ = $3; }
 344         ;
 345
 346 parameter_declaration_list_opt:
 347         /* empty */                                     { $$ = NULL; }
 348         | parameter_declaration_list
 349         ;
 350
 351 parameter_declaration_list:
 352         parameter_declaration
 353         | parameter_declaration_list ',' parameter_declaration
 354                 { $$ = $3; }
 355         ;
 356
 357 parameter_declaration:
 358         decl_specifier_seq m_abstract_declarator
 359                 { $$ = $2 ? $2 : $1; }
 360         ;
 361
 362 m_abstract_declarator:
 363         ptr_operator m_abstract_declarator
 364                 { $$ = $2 ? $2 : $1; }
 365         | direct_m_abstract_declarator
 366         ;
 367
 368 direct_m_abstract_declarator:
 369         /* empty */                                     { $$ = NULL; }
 370         | IDENT
 371                 { /* For version 2 checksums, we don't want to remember
 372                      private parameter names.  */
 373                   remove_node($1);
 374                   $$ = $1;
 375                 }
 376         /* This wasn't really a typedef name but an identifier that
 377            shadows one.  */
 378         | TYPE
 379                 { remove_node($1);
 380                   $$ = $1;
 381                 }
 382         | direct_m_abstract_declarator '(' parameter_declaration_clause ')'
 383                 { $$ = $4; }
 384         | direct_m_abstract_declarator '(' error ')'
 385                 { $$ = $4; }
 386         | direct_m_abstract_declarator BRACKET_PHRASE
 387                 { $$ = $2; }
 388         | '(' m_abstract_declarator ')'
 389                 { $$ = $3; }
 390         | '(' error ')'
 391                 { $$ = $3; }
 392         ;
 393
 394 function_definition:
 395         decl_specifier_seq_opt declarator BRACE_PHRASE
 396                 { struct string_list *decl = *$2;
 397                   *$2 = NULL;
 398                   add_symbol(current_name, SYM_NORMAL, decl, is_extern);
 399                   $$ = $3;
 400                 }
 401         ;
 402
 403 initializer_opt:
 404         /* empty */                                     { $$ = NULL; }
 405         | initializer
 406         ;
 407
 408 /* We never care about the contents of an initializer.  */
 409 initializer:
 410         '=' EXPRESSION_PHRASE
 411                 { remove_list($2, &(*$1)->next); $$ = $2; }
 412         ;
 413
 414 class_body:
 415         '{' member_specification_opt '}'                { $$ = $3; }
 416         | '{' error '}'                                 { $$ = $3; }
 417         ;
 418
 419 member_specification_opt:
 420         /* empty */                                     { $$ = NULL; }
 421         | member_specification
 422         ;
 423
 424 member_specification:
 425         member_declaration
 426         | member_specification member_declaration       { $$ = $2; }
 427         ;
 428
 429 member_declaration:
 430         decl_specifier_seq_opt member_declarator_list_opt ';'
 431                 { $$ = $3; }
 432         | error ';'
 433                 { $$ = $2; }
 434         ;
 435
 436 member_declarator_list_opt:
 437         /* empty */                                     { $$ = NULL; }
 438         | member_declarator_list
 439         ;
 440
 441 member_declarator_list:
 442         member_declarator
 443         | member_declarator_list ',' member_declarator  { $$ = $3; }
 444         ;
 445
 446 member_declarator:
 447         nested_declarator attribute_opt                 { $$ = $2 ? $2 : $1; }
 448         | IDENT member_bitfield_declarator              { $$ = $2; }
 449         | member_bitfield_declarator
 450         ;
 451
 452 member_bitfield_declarator:
 453         ':' EXPRESSION_PHRASE                           { $$ = $2; }
 454         ;
 455
 456 attribute_opt:
 457         /* empty */                                     { $$ = NULL; }
 458         | attribute_opt ATTRIBUTE_PHRASE
 459         ;
 460
 461 enum_body:
 462         '{' enumerator_list '}'                         { $$ = $3; }
 463         | '{' enumerator_list ',' '}'                   { $$ = $4; }
 464          ;
 465
 466 enumerator_list:
 467         enumerator
 468         | enumerator_list ',' enumerator
 469
 470 enumerator:
 471         IDENT
 472                 {
 473                         const char *name = strdup((*$1)->string);
 474                         add_symbol(name, SYM_ENUM_CONST, NULL, 0);
 475                 }
 476         | IDENT '=' EXPRESSION_PHRASE
 477                 {
 478                         const char *name = strdup((*$1)->string);
 479                         struct string_list *expr = copy_list_range(*$3, *$2);
 480                         add_symbol(name, SYM_ENUM_CONST, expr, 0);
 481                 }
 482
 483 asm_definition:
 484         ASM_PHRASE ';'                                  { $$ = $2; }
 485         ;
 486
 487 asm_phrase_opt:
 488         /* empty */                                     { $$ = NULL; }
 489         | ASM_PHRASE
 490         ;
 491
 492 export_definition:
 493         EXPORT_SYMBOL_KEYW '(' IDENT ')' ';'
 494                 { export_symbol((*$3)->string); $$ = $5; }
 495         ;
 496
 497
 498 %%
 499
 500 static void
 501 yyerror(const char *e)
 502 {
 503   error_with_pos("%s", e);
 504 }