1 # C++ GLR skeleton for Bison 2 3 # Copyright (C) 2002-2015, 2018-2021 Free Software Foundation, Inc. 4 5 # This program is free software: you can redistribute it and/or modify 6 # it under the terms of the GNU General Public License as published by 7 # the Free Software Foundation, either version 3 of the License, or 8 # (at your option) any later version. 9 # 10 # This program is distributed in the hope that it will be useful, 11 # but WITHOUT ANY WARRANTY; without even the implied warranty of 12 # MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 13 # GNU General Public License for more details. 14 # 15 # You should have received a copy of the GNU General Public License 16 # along with this program. If not, see <https://www.gnu.org/licenses/>. 17 18 19 # This skeleton produces a C++ class that encapsulates a C glr parser. 20 # This is in order to reduce the maintenance burden. The glr.c 21 # skeleton is clean and pure enough so that there are no real 22 # problems. The C++ interface is the same as that of lalr1.cc. In 23 # fact, glr.c can replace yacc.c without the user noticing any 24 # difference, and similarly for glr.cc replacing lalr1.cc. 25 # 26 # The passing of parse-params 27 # 28 # The additional arguments are stored as members of the parser 29 # object, yyparser. The C routines need to carry yyparser 30 # throughout the C parser; that's easy: make yyparser an 31 # additional parse-param. But because the C++ skeleton needs to 32 # know the "real" original parse-param, we save them 33 # (b4_parse_param_orig). Note that b4_parse_param is overquoted 34 # (and c.m4 strips one level of quotes). This is a PITA, and 35 # explains why there are so many levels of quotes. 36 # 37 # The locations 38 # 39 # We use location.cc just like lalr1.cc, but because glr.c stores 40 # the locations in a union, the position and location classes 41 # must not have a constructor. Therefore, contrary to lalr1.cc, we 42 # must not define "b4_location_constructors". As a consequence the 43 # user must initialize the first positions (in particular the 44 # filename member). 45 46 # We require a pure interface. 47 m4_define([b4_pure_flag], [1]) 48 49 m4_include(b4_skeletonsdir/[c++.m4]) 50 b4_bison_locations_if([m4_include(b4_skeletonsdir/[location.cc])]) 51 52 m4_define([b4_parser_class], 53 [b4_percent_define_get([[api.parser.class]])]) 54 55 # Save the parse parameters. 56 m4_define([b4_parse_param_orig], m4_defn([b4_parse_param])) 57 58 # b4_parse_param_wrap 59 # ------------------- 60 # New ones. 61 m4_ifset([b4_parse_param], 62 [m4_define([b4_parse_param_wrap], 63 [[b4_namespace_ref::b4_parser_class[& yyparser], [[yyparser]]],] 64 m4_defn([b4_parse_param]))], 65 [m4_define([b4_parse_param_wrap], 66 [[b4_namespace_ref::b4_parser_class[& yyparser], [[yyparser]]]]) 67 ]) 68 69 70 # b4_yy_symbol_print_define 71 # ------------------------- 72 # Bypass the default implementation to generate the "yy_symbol_print" 73 # and "yy_symbol_value_print" functions. 74 m4_define([b4_yy_symbol_print_define], 75 [[/*--------------------. 76 | Print this symbol. | 77 `--------------------*/ 78 79 static void 80 yy_symbol_print (FILE *, ]b4_namespace_ref::b4_parser_class[::symbol_kind_type yytoken, 81 const ]b4_namespace_ref::b4_parser_class[::value_type *yyvaluep]b4_locations_if([[, 82 const ]b4_namespace_ref::b4_parser_class[::location_type *yylocationp]])[]b4_user_formals[) 83 { 84 ]b4_parse_param_use[]dnl 85 [ yyparser.yy_symbol_print_ (yytoken, yyvaluep]b4_locations_if([, yylocationp])[); 86 } 87 ]])[ 88 89 # Hijack the initial action to initialize the locations. 90 ]b4_bison_locations_if([m4_define([b4_initial_action], 91 [yylloc.initialize ();]m4_ifdef([b4_initial_action], [ 92 m4_defn([b4_initial_action])]))])[ 93 94 # Hijack the post prologue to declare yyerror. 95 ]m4_append([b4_post_prologue], 96 [b4_syncline([@oline@], [@ofile@])dnl 97 [static void 98 yyerror (]b4_locations_if([[const ]b4_namespace_ref::b4_parser_class[::location_type *yylocationp, 99 ]])[]m4_ifset([b4_parse_param], [b4_formals(b4_parse_param), 100 ])[const char* msg);]])[ 101 102 # Inserted before the epilogue to define implementations (yyerror, parser member 103 # functions etc.). 104 ]m4_define([b4_glr_cc_pre_epilogue], 105 [b4_syncline([@oline@], [@ofile@])dnl 106 [ 107 /*------------------. 108 | Report an error. | 109 `------------------*/ 110 111 static void 112 yyerror (]b4_locations_if([[const ]b4_namespace_ref::b4_parser_class[::location_type *yylocationp, 113 ]])[]m4_ifset([b4_parse_param], [b4_formals(b4_parse_param), 114 ])[const char* msg) 115 { 116 ]b4_parse_param_use[]dnl 117 [ yyparser.error (]b4_locations_if([[*yylocationp, ]])[msg); 118 } 119 120 121 ]b4_namespace_open[ 122 ]dnl In this section, the parse params are the original parse_params. 123 m4_pushdef([b4_parse_param], m4_defn([b4_parse_param_orig]))dnl 124 [ /// Build a parser object. 125 ]b4_parser_class::b4_parser_class[ (]b4_parse_param_decl[)]m4_ifset([b4_parse_param], [ 126 :])[ 127 #if ]b4_api_PREFIX[DEBUG 128 ]m4_ifset([b4_parse_param], [ ], [ :])[yycdebug_ (&std::cerr)]m4_ifset([b4_parse_param], [,])[ 129 #endif]b4_parse_param_cons[ 130 {} 131 132 ]b4_parser_class::~b4_parser_class[ () 133 {} 134 135 ]b4_parser_class[::syntax_error::~syntax_error () YY_NOEXCEPT YY_NOTHROW 136 {} 137 138 int 139 ]b4_parser_class[::operator() () 140 { 141 return parse (); 142 } 143 144 int 145 ]b4_parser_class[::parse () 146 { 147 return ::yy_parse_impl (*this]b4_user_args[); 148 } 149 150 #if ]b4_api_PREFIX[DEBUG 151 /*--------------------. 152 | Print this symbol. | 153 `--------------------*/ 154 155 void 156 ]b4_parser_class[::yy_symbol_value_print_ (symbol_kind_type yykind, 157 const value_type* yyvaluep]b4_locations_if([[, 158 const location_type* yylocationp]])[) const 159 {]b4_locations_if([[ 160 YY_USE (yylocationp);]])[ 161 YY_USE (yyvaluep); 162 std::ostream& yyo = debug_stream (); 163 std::ostream& yyoutput = yyo; 164 YY_USE (yyoutput); 165 ]b4_symbol_actions([printer])[ 166 } 167 168 169 void 170 ]b4_parser_class[::yy_symbol_print_ (symbol_kind_type yykind, 171 const value_type* yyvaluep]b4_locations_if([[, 172 const location_type* yylocationp]])[) const 173 { 174 *yycdebug_ << (yykind < YYNTOKENS ? "token" : "nterm") 175 << ' ' << yysymbol_name (yykind) << " ("]b4_locations_if([[ 176 << *yylocationp << ": "]])[; 177 yy_symbol_value_print_ (yykind, yyvaluep]b4_locations_if([[, yylocationp]])[); 178 *yycdebug_ << ')'; 179 } 180 181 std::ostream& 182 ]b4_parser_class[::debug_stream () const 183 { 184 return *yycdebug_; 185 } 186 187 void 188 ]b4_parser_class[::set_debug_stream (std::ostream& o) 189 { 190 yycdebug_ = &o; 191 } 192 193 194 ]b4_parser_class[::debug_level_type 195 ]b4_parser_class[::debug_level () const 196 { 197 return yydebug; 198 } 199 200 void 201 ]b4_parser_class[::set_debug_level (debug_level_type l) 202 { 203 // Actually, it is yydebug which is really used. 204 yydebug = l; 205 } 206 207 #endif 208 ]m4_popdef([b4_parse_param])dnl 209 b4_namespace_close[]dnl 210 ]) 211 212 213 m4_define([b4_define_symbol_kind], 214 [m4_format([#define %-15s %s], 215 b4_symbol($][1, kind_base), 216 b4_namespace_ref[::]b4_parser_class[::symbol_kind::]b4_symbol($1, kind_base)) 217 ]) 218 219 # b4_glr_cc_setup 220 # --------------- 221 # Setup redirections for glr.c: Map the names used in c.m4 to the ones used 222 # in c++.m4. 223 m4_define([b4_glr_cc_setup], 224 [[]b4_attribute_define[ 225 ]b4_null_define[ 226 227 // This skeleton is based on C, yet compiles it as C++. 228 // So expect warnings about C style casts. 229 #if defined __clang__ && 306 <= __clang_major__ * 100 + __clang_minor__ 230 # pragma clang diagnostic ignored "-Wold-style-cast" 231 #elif defined __GNUC__ && 406 <= __GNUC__ * 100 + __GNUC_MINOR__ 232 # pragma GCC diagnostic ignored "-Wold-style-cast" 233 #endif 234 235 // On MacOS, PTRDIFF_MAX is defined as long long, which Clang's 236 // -pedantic reports as being a C++11 extension. 237 #if defined __APPLE__ && YY_CPLUSPLUS < 201103L \ 238 && defined __clang__ && 4 <= __clang_major__ 239 # pragma clang diagnostic ignored "-Wc++11-long-long" 240 #endif 241 242 #undef ]b4_symbol(empty, [id])[ 243 #define ]b4_symbol(empty, [id])[ ]b4_namespace_ref[::]b4_parser_class[::token::]b4_symbol(empty, [id])[ 244 #undef ]b4_symbol(eof, [id])[ 245 #define ]b4_symbol(eof, [id])[ ]b4_namespace_ref[::]b4_parser_class[::token::]b4_symbol(eof, [id])[ 246 #undef ]b4_symbol(error, [id])[ 247 #define ]b4_symbol(error, [id])[ ]b4_namespace_ref[::]b4_parser_class[::token::]b4_symbol(error, [id])[ 248 249 #ifndef ]b4_api_PREFIX[STYPE 250 # define ]b4_api_PREFIX[STYPE ]b4_namespace_ref[::]b4_parser_class[::value_type 251 #endif 252 #ifndef ]b4_api_PREFIX[LTYPE 253 # define ]b4_api_PREFIX[LTYPE ]b4_namespace_ref[::]b4_parser_class[::location_type 254 #endif 255 256 typedef ]b4_namespace_ref[::]b4_parser_class[::symbol_kind_type yysymbol_kind_t; 257 258 // Expose C++ symbol kinds to C. 259 ]b4_define_symbol_kind(-2)dnl 260 b4_symbol_foreach([b4_define_symbol_kind])])[ 261 ]]) 262 263 264 m4_define([b4_undef_symbol_kind], 265 [[#undef ]b4_symbol($1, kind_base)[ 266 ]]) 267 268 269 # b4_glr_cc_cleanup 270 # ----------------- 271 # Remove redirections for glr.c. 272 m4_define([b4_glr_cc_cleanup], 273 [[#undef ]b4_symbol(empty, [id])[ 274 #undef ]b4_symbol(eof, [id])[ 275 #undef ]b4_symbol(error, [id])[ 276 277 ]b4_undef_symbol_kind(-2)dnl 278 b4_symbol_foreach([b4_undef_symbol_kind])dnl 279 ]) 280 281 282 # b4_shared_declarations(hh|cc) 283 # ----------------------------- 284 # Declaration that might either go into the header (if --header, $1 = hh) 285 # or in the implementation file. 286 m4_define([b4_shared_declarations], 287 [m4_pushdef([b4_parse_param], m4_defn([b4_parse_param_orig]))dnl 288 b4_percent_code_get([[requires]])[ 289 #include <iostream> 290 #include <stdexcept> 291 #include <string> 292 293 ]b4_cxx_portability[ 294 ]m4_ifdef([b4_location_include], 295 [[# include ]b4_location_include])[ 296 ]b4_variant_if([b4_variant_includes])[ 297 298 // Whether we are compiled with exception support. 299 #ifndef YY_EXCEPTIONS 300 # if defined __GNUC__ && !defined __EXCEPTIONS 301 # define YY_EXCEPTIONS 0 302 # else 303 # define YY_EXCEPTIONS 1 304 # endif 305 #endif 306 307 ]b4_YYDEBUG_define[ 308 309 ]b4_namespace_open[ 310 311 ]b4_bison_locations_if([m4_ifndef([b4_location_file], 312 [b4_location_define])])[ 313 314 /// A Bison parser. 315 class ]b4_parser_class[ 316 { 317 public: 318 ]b4_public_types_declare[ 319 320 /// Build a parser object. 321 ]b4_parser_class[ (]b4_parse_param_decl[); 322 virtual ~]b4_parser_class[ (); 323 324 /// Parse. An alias for parse (). 325 /// \returns 0 iff parsing succeeded. 326 int operator() (); 327 328 /// Parse. 329 /// \returns 0 iff parsing succeeded. 330 virtual int parse (); 331 332 #if ]b4_api_PREFIX[DEBUG 333 /// The current debugging stream. 334 std::ostream& debug_stream () const; 335 /// Set the current debugging stream. 336 void set_debug_stream (std::ostream &); 337 338 /// Type for debugging levels. 339 typedef int debug_level_type; 340 /// The current debugging level. 341 debug_level_type debug_level () const; 342 /// Set the current debugging level. 343 void set_debug_level (debug_level_type l); 344 #endif 345 346 /// Report a syntax error.]b4_locations_if([[ 347 /// \param loc where the syntax error is found.]])[ 348 /// \param msg a description of the syntax error. 349 virtual void error (]b4_locations_if([[const location_type& loc, ]])[const std::string& msg); 350 351 # if ]b4_api_PREFIX[DEBUG 352 public: 353 /// \brief Report a symbol value on the debug stream. 354 /// \param yykind The symbol kind. 355 /// \param yyvaluep Its semantic value.]b4_locations_if([[ 356 /// \param yylocationp Its location.]])[ 357 virtual void yy_symbol_value_print_ (symbol_kind_type yykind, 358 const value_type* yyvaluep]b4_locations_if([[, 359 const location_type* yylocationp]])[) const; 360 /// \brief Report a symbol on the debug stream. 361 /// \param yykind The symbol kind. 362 /// \param yyvaluep Its semantic value.]b4_locations_if([[ 363 /// \param yylocationp Its location.]])[ 364 virtual void yy_symbol_print_ (symbol_kind_type yykind, 365 const value_type* yyvaluep]b4_locations_if([[, 366 const location_type* yylocationp]])[) const; 367 private: 368 /// Debug stream. 369 std::ostream* yycdebug_; 370 #endif 371 372 ]b4_parse_param_vars[ 373 }; 374 375 ]b4_namespace_close[ 376 377 ]b4_percent_code_get([[provides]])[ 378 ]m4_popdef([b4_parse_param])dnl 379 ])[ 380 381 ]b4_header_if( 382 [b4_output_begin([b4_spec_header_file]) 383 b4_copyright([Skeleton interface for Bison GLR parsers in C++], 384 [2002-2015, 2018-2021])[ 385 // C++ GLR parser skeleton written by Akim Demaille. 386 387 ]b4_disclaimer[ 388 ]b4_cpp_guard_open([b4_spec_mapped_header_file])[ 389 ]b4_shared_declarations[ 390 ]b4_cpp_guard_close([b4_spec_mapped_header_file])[ 391 ]b4_output_end]) 392 393 # Let glr.c (and b4_shared_declarations) believe that the user 394 # arguments include the parser itself. 395 m4_pushdef([b4_parse_param], m4_defn([b4_parse_param_wrap])) 396 m4_include(b4_skeletonsdir/[glr.c]) 397 m4_popdef([b4_parse_param]) 398