1 /* Source-language-related definitions for GDB. 2 3 Copyright (C) 1991-2017 Free Software Foundation, Inc. 4 5 Contributed by the Department of Computer Science at the State University 6 of New York at Buffalo. 7 8 This file is part of GDB. 9 10 This program is free software; you can redistribute it and/or modify 11 it under the terms of the GNU General Public License as published by 12 the Free Software Foundation; either version 3 of the License, or 13 (at your option) any later version. 14 15 This program is distributed in the hope that it will be useful, 16 but WITHOUT ANY WARRANTY; without even the implied warranty of 17 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 18 GNU General Public License for more details. 19 20 You should have received a copy of the GNU General Public License 21 along with this program. If not, see <http://www.gnu.org/licenses/>. */ 22 23 #if !defined (LANGUAGE_H) 24 #define LANGUAGE_H 1 25 26 #include "symtab.h" 27 #include "common/function-view.h" 28 29 /* Forward decls for prototypes. */ 30 struct value; 31 struct objfile; 32 struct frame_info; 33 struct expression; 34 struct ui_file; 35 struct value_print_options; 36 struct type_print_options; 37 struct lang_varobj_ops; 38 struct parser_state; 39 struct compile_instance; 40 41 #define MAX_FORTRAN_DIMS 7 /* Maximum number of F77 array dims. */ 42 43 /* range_mode == 44 range_mode_auto: range_check set automatically to default of language. 45 range_mode_manual: range_check set manually by user. */ 46 47 extern enum range_mode 48 { 49 range_mode_auto, range_mode_manual 50 } 51 range_mode; 52 53 /* range_check == 54 range_check_on: Ranges are checked in GDB expressions, producing errors. 55 range_check_warn: Ranges are checked, producing warnings. 56 range_check_off: Ranges are not checked in GDB expressions. */ 57 58 extern enum range_check 59 { 60 range_check_off, range_check_warn, range_check_on 61 } 62 range_check; 63 64 /* case_mode == 65 case_mode_auto: case_sensitivity set upon selection of scope. 66 case_mode_manual: case_sensitivity set only by user. */ 67 68 extern enum case_mode 69 { 70 case_mode_auto, case_mode_manual 71 } 72 case_mode; 73 74 /* array_ordering == 75 array_row_major: Arrays are in row major order. 76 array_column_major: Arrays are in column major order. */ 77 78 extern enum array_ordering 79 { 80 array_row_major, array_column_major 81 } 82 array_ordering; 83 84 85 /* case_sensitivity == 86 case_sensitive_on: Case sensitivity in name matching is used. 87 case_sensitive_off: Case sensitivity in name matching is not used. */ 88 89 extern enum case_sensitivity 90 { 91 case_sensitive_on, case_sensitive_off 92 } 93 case_sensitivity; 94 95 96 /* macro_expansion == 97 macro_expansion_no: No macro expansion is available. 98 macro_expansion_c: C-like macro expansion is available. */ 99 100 enum macro_expansion 101 { 102 macro_expansion_no, macro_expansion_c 103 }; 104 105 106 /* Per architecture (OS/ABI) language information. */ 107 108 struct language_arch_info 109 { 110 /* Its primitive types. This is a vector ended by a NULL pointer. 111 These types can be specified by name in parsing types in 112 expressions, regardless of whether the program being debugged 113 actually defines such a type. */ 114 struct type **primitive_type_vector; 115 116 /* Symbol wrappers around primitive_type_vector, so that the symbol lookup 117 machinery can return them. */ 118 struct symbol **primitive_type_symbols; 119 120 /* Type of elements of strings. */ 121 struct type *string_char_type; 122 123 /* Symbol name of type to use as boolean type, if defined. */ 124 const char *bool_type_symbol; 125 /* Otherwise, this is the default boolean builtin type. */ 126 struct type *bool_type_default; 127 }; 128 129 /* A pointer to a function expected to return nonzero if 130 SYMBOL_SEARCH_NAME matches the given LOOKUP_NAME. 131 132 SYMBOL_SEARCH_NAME should be a symbol's "search" name. 133 LOOKUP_NAME should be the name of an entity after it has been 134 transformed for lookup. */ 135 136 typedef int (*symbol_name_cmp_ftype) (const char *symbol_search_name, 137 const char *lookup_name); 138 139 /* Structure tying together assorted information about a language. */ 140 141 struct language_defn 142 { 143 /* Name of the language. */ 144 145 const char *la_name; 146 147 /* Natural or official name of the language. */ 148 149 const char *la_natural_name; 150 151 /* its symtab language-enum (defs.h). */ 152 153 enum language la_language; 154 155 /* Default range checking. */ 156 157 enum range_check la_range_check; 158 159 /* Default case sensitivity. */ 160 enum case_sensitivity la_case_sensitivity; 161 162 /* Multi-dimensional array ordering. */ 163 enum array_ordering la_array_ordering; 164 165 /* Style of macro expansion, if any, supported by this language. */ 166 enum macro_expansion la_macro_expansion; 167 168 /* A NULL-terminated array of file extensions for this language. 169 The extension must include the ".", like ".c". If this 170 language doesn't need to provide any filename extensions, this 171 may be NULL. */ 172 173 const char *const *la_filename_extensions; 174 175 /* Definitions related to expression printing, prefixifying, and 176 dumping. */ 177 178 const struct exp_descriptor *la_exp_desc; 179 180 /* Parser function. */ 181 182 int (*la_parser) (struct parser_state *); 183 184 /* Parser error function. */ 185 186 void (*la_error) (const char *); 187 188 /* Given an expression *EXPP created by prefixifying the result of 189 la_parser, perform any remaining processing necessary to complete 190 its translation. *EXPP may change; la_post_parser is responsible 191 for releasing its previous contents, if necessary. If 192 VOID_CONTEXT_P, then no value is expected from the expression. */ 193 194 void (*la_post_parser) (struct expression ** expp, int void_context_p); 195 196 void (*la_printchar) (int ch, struct type *chtype, 197 struct ui_file * stream); 198 199 void (*la_printstr) (struct ui_file * stream, struct type *elttype, 200 const gdb_byte *string, unsigned int length, 201 const char *encoding, int force_ellipses, 202 const struct value_print_options *); 203 204 void (*la_emitchar) (int ch, struct type *chtype, 205 struct ui_file * stream, int quoter); 206 207 /* Print a type using syntax appropriate for this language. */ 208 209 void (*la_print_type) (struct type *, const char *, struct ui_file *, int, 210 int, const struct type_print_options *); 211 212 /* Print a typedef using syntax appropriate for this language. 213 TYPE is the underlying type. NEW_SYMBOL is the symbol naming 214 the type. STREAM is the output stream on which to print. */ 215 216 void (*la_print_typedef) (struct type *type, struct symbol *new_symbol, 217 struct ui_file *stream); 218 219 /* Print a value using syntax appropriate for this language. 220 221 TYPE is the type of the sub-object to be printed. 222 223 EMBEDDED_OFFSET is the offset into the outermost object of the 224 sub-object represented by TYPE. This is the object which this 225 call should print. Note that the enclosing type is not 226 available. 227 228 ADDRESS is the address in the inferior of the enclosing object. 229 230 STREAM is the stream on which the value is to be printed. 231 232 RECURSE is the recursion depth. It is zero-based. 233 234 OPTIONS are the formatting options to be used when 235 printing. */ 236 237 void (*la_val_print) (struct type *type, 238 int embedded_offset, CORE_ADDR address, 239 struct ui_file *stream, int recurse, 240 struct value *val, 241 const struct value_print_options *options); 242 243 /* Print a top-level value using syntax appropriate for this language. */ 244 245 void (*la_value_print) (struct value *, struct ui_file *, 246 const struct value_print_options *); 247 248 /* Given a symbol VAR, the corresponding block VAR_BLOCK (if any) and a 249 stack frame id FRAME, read the value of the variable and return (pointer 250 to a) struct value containing the value. 251 252 VAR_BLOCK is needed if there's a possibility for VAR to be outside 253 FRAME. This is what happens if FRAME correspond to a nested function 254 and VAR is defined in the outer function. If callers know that VAR is 255 located in FRAME or is global/static, NULL can be passed as VAR_BLOCK. 256 257 Throw an error if the variable cannot be found. */ 258 259 struct value *(*la_read_var_value) (struct symbol *var, 260 const struct block *var_block, 261 struct frame_info *frame); 262 263 /* PC is possibly an unknown languages trampoline. 264 If that PC falls in a trampoline belonging to this language, 265 return the address of the first pc in the real function, or 0 266 if it isn't a language tramp for this language. */ 267 CORE_ADDR (*skip_trampoline) (struct frame_info *, CORE_ADDR); 268 269 /* Now come some hooks for lookup_symbol. */ 270 271 /* If this is non-NULL, specifies the name that of the implicit 272 local variable that refers to the current object instance. */ 273 274 const char *la_name_of_this; 275 276 /* This is a function that lookup_symbol will call when it gets to 277 the part of symbol lookup where C looks up static and global 278 variables. */ 279 280 struct block_symbol (*la_lookup_symbol_nonlocal) 281 (const struct language_defn *, 282 const char *, 283 const struct block *, 284 const domain_enum); 285 286 /* Find the definition of the type with the given name. */ 287 struct type *(*la_lookup_transparent_type) (const char *); 288 289 /* Return demangled language symbol, or NULL. */ 290 char *(*la_demangle) (const char *mangled, int options); 291 292 /* Demangle a symbol according to this language's rules. Unlike 293 la_demangle, this does not take any options. 294 295 *DEMANGLED will be set by this function. 296 297 If this function returns 0, then *DEMANGLED must always be set 298 to NULL. 299 300 If this function returns 1, the implementation may set this to 301 a xmalloc'd string holding the demangled form. However, it is 302 not required to. The string, if any, is owned by the caller. 303 304 The resulting string should be of the form that will be 305 installed into a symbol. */ 306 int (*la_sniff_from_mangled_name) (const char *mangled, char **demangled); 307 308 /* Return class name of a mangled method name or NULL. */ 309 char *(*la_class_name_from_physname) (const char *physname); 310 311 /* Table for printing expressions. */ 312 313 const struct op_print *la_op_print_tab; 314 315 /* Zero if the language has first-class arrays. True if there are no 316 array values, and array objects decay to pointers, as in C. */ 317 318 char c_style_arrays; 319 320 /* Index to use for extracting the first element of a string. */ 321 char string_lower_bound; 322 323 /* The list of characters forming word boundaries. */ 324 const char *(*la_word_break_characters) (void); 325 326 /* Should return a vector of all symbols which are possible 327 completions for TEXT. WORD is the entire command on which the 328 completion is being made. If CODE is TYPE_CODE_UNDEF, then all 329 symbols should be examined; otherwise, only STRUCT_DOMAIN 330 symbols whose type has a code of CODE should be matched. */ 331 VEC (char_ptr) *(*la_make_symbol_completion_list) (const char *text, 332 const char *word, 333 enum type_code code); 334 335 /* The per-architecture (OS/ABI) language information. */ 336 void (*la_language_arch_info) (struct gdbarch *, 337 struct language_arch_info *); 338 339 /* Print the index of an element of an array. */ 340 void (*la_print_array_index) (struct value *index_value, 341 struct ui_file *stream, 342 const struct value_print_options *options); 343 344 /* Return non-zero if TYPE should be passed (and returned) by 345 reference at the language level. */ 346 int (*la_pass_by_reference) (struct type *type); 347 348 /* Obtain a string from the inferior, storing it in a newly allocated 349 buffer in BUFFER, which should be freed by the caller. If the 350 in- and out-parameter *LENGTH is specified at -1, the string is 351 read until a null character of the appropriate width is found - 352 otherwise the string is read to the length of characters specified. 353 On completion, *LENGTH will hold the size of the string in characters. 354 If a *LENGTH of -1 was specified it will count only actual 355 characters, excluding any eventual terminating null character. 356 Otherwise *LENGTH will include all characters - including any nulls. 357 CHARSET will hold the encoding used in the string. */ 358 void (*la_get_string) (struct value *value, gdb_byte **buffer, int *length, 359 struct type **chartype, const char **charset); 360 361 /* Return a pointer to the function that should be used to match 362 a symbol name against LOOKUP_NAME. This is mostly for languages 363 such as Ada where the matching algorithm depends on LOOKUP_NAME. 364 365 This field may be NULL, in which case strcmp_iw will be used 366 to perform the matching. */ 367 symbol_name_cmp_ftype (*la_get_symbol_name_cmp) (const char *lookup_name); 368 369 /* Find all symbols in the current program space matching NAME in 370 DOMAIN, according to this language's rules. 371 372 The search is done in BLOCK only. 373 The caller is responsible for iterating up through superblocks 374 if desired. 375 376 For each one, call CALLBACK with the symbol. If CALLBACK 377 returns false, the iteration ends at that point. 378 379 This field may not be NULL. If the language does not need any 380 special processing here, 'iterate_over_symbols' should be 381 used as the definition. */ 382 void (*la_iterate_over_symbols) 383 (const struct block *block, const char *name, domain_enum domain, 384 gdb::function_view<symbol_found_callback_ftype> callback); 385 386 /* Various operations on varobj. */ 387 const struct lang_varobj_ops *la_varobj_ops; 388 389 /* If this language allows compilation from the gdb command line, 390 this method should be non-NULL. When called it should return 391 an instance of struct gcc_context appropriate to the language. 392 When defined this method must never return NULL; instead it 393 should throw an exception on failure. The returned compiler 394 instance is owned by its caller and must be deallocated by 395 calling its 'destroy' method. */ 396 397 struct compile_instance *(*la_get_compile_instance) (void); 398 399 /* This method must be defined if 'la_get_gcc_context' is defined. 400 If 'la_get_gcc_context' is not defined, then this method is 401 ignored. 402 403 This takes the user-supplied text and returns a new bit of code 404 to compile. 405 406 INST is the compiler instance being used. 407 INPUT is the user's input text. 408 GDBARCH is the architecture to use. 409 EXPR_BLOCK is the block in which the expression is being 410 parsed. 411 EXPR_PC is the PC at which the expression is being parsed. */ 412 413 std::string (*la_compute_program) (struct compile_instance *inst, 414 const char *input, 415 struct gdbarch *gdbarch, 416 const struct block *expr_block, 417 CORE_ADDR expr_pc); 418 419 /* Add fields above this point, so the magic number is always last. */ 420 /* Magic number for compat checking. */ 421 422 long la_magic; 423 424 }; 425 426 #define LANG_MAGIC 910823L 427 428 /* Pointer to the language_defn for our current language. This pointer 429 always points to *some* valid struct; it can be used without checking 430 it for validity. 431 432 The current language affects expression parsing and evaluation 433 (FIXME: it might be cleaner to make the evaluation-related stuff 434 separate exp_opcodes for each different set of semantics. We 435 should at least think this through more clearly with respect to 436 what happens if the language is changed between parsing and 437 evaluation) and printing of things like types and arrays. It does 438 *not* affect symbol-reading-- each source file in a symbol-file has 439 its own language and we should keep track of that regardless of the 440 language when symbols are read. If we want some manual setting for 441 the language of symbol files (e.g. detecting when ".c" files are 442 C++), it should be a separate setting from the current_language. */ 443 444 extern const struct language_defn *current_language; 445 446 /* Pointer to the language_defn expected by the user, e.g. the language 447 of main(), or the language we last mentioned in a message, or C. */ 448 449 extern const struct language_defn *expected_language; 450 451 /* language_mode == 452 language_mode_auto: current_language automatically set upon selection 453 of scope (e.g. stack frame) 454 language_mode_manual: current_language set only by user. */ 455 456 extern enum language_mode 457 { 458 language_mode_auto, language_mode_manual 459 } 460 language_mode; 461 462 struct type *language_bool_type (const struct language_defn *l, 463 struct gdbarch *gdbarch); 464 465 struct type *language_string_char_type (const struct language_defn *l, 466 struct gdbarch *gdbarch); 467 468 /* Look up type NAME in language L, and return its definition for architecture 469 GDBARCH. Returns NULL if not found. */ 470 471 struct type *language_lookup_primitive_type (const struct language_defn *l, 472 struct gdbarch *gdbarch, 473 const char *name); 474 475 /* Wrapper around language_lookup_primitive_type to return the 476 corresponding symbol. */ 477 478 struct symbol * 479 language_lookup_primitive_type_as_symbol (const struct language_defn *l, 480 struct gdbarch *gdbarch, 481 const char *name); 482 483 484 /* These macros define the behaviour of the expression 485 evaluator. */ 486 487 /* Should we range check values against the domain of their type? */ 488 #define RANGE_CHECK (range_check != range_check_off) 489 490 /* "cast" really means conversion. */ 491 /* FIXME -- should be a setting in language_defn. */ 492 #define CAST_IS_CONVERSION(LANG) ((LANG)->la_language == language_c || \ 493 (LANG)->la_language == language_cplus || \ 494 (LANG)->la_language == language_objc) 495 496 extern void language_info (int); 497 498 extern enum language set_language (enum language); 499 500 501 /* This page contains functions that return things that are 502 specific to languages. Each of these functions is based on 503 the current setting of working_lang, which the user sets 504 with the "set language" command. */ 505 506 #define LA_PRINT_TYPE(type,varstring,stream,show,level,flags) \ 507 (current_language->la_print_type(type,varstring,stream,show,level,flags)) 508 509 #define LA_PRINT_TYPEDEF(type,new_symbol,stream) \ 510 (current_language->la_print_typedef(type,new_symbol,stream)) 511 512 #define LA_VALUE_PRINT(val,stream,options) \ 513 (current_language->la_value_print(val,stream,options)) 514 515 #define LA_PRINT_CHAR(ch, type, stream) \ 516 (current_language->la_printchar(ch, type, stream)) 517 #define LA_PRINT_STRING(stream, elttype, string, length, encoding, force_ellipses, options) \ 518 (current_language->la_printstr(stream, elttype, string, length, \ 519 encoding, force_ellipses,options)) 520 #define LA_EMIT_CHAR(ch, type, stream, quoter) \ 521 (current_language->la_emitchar(ch, type, stream, quoter)) 522 #define LA_GET_STRING(value, buffer, length, chartype, encoding) \ 523 (current_language->la_get_string(value, buffer, length, chartype, encoding)) 524 525 #define LA_PRINT_ARRAY_INDEX(index_value, stream, options) \ 526 (current_language->la_print_array_index(index_value, stream, options)) 527 528 #define LA_ITERATE_OVER_SYMBOLS(BLOCK, NAME, DOMAIN, CALLBACK) \ 529 (current_language->la_iterate_over_symbols (BLOCK, NAME, DOMAIN, CALLBACK)) 530 531 /* Test a character to decide whether it can be printed in literal form 532 or needs to be printed in another representation. For example, 533 in C the literal form of the character with octal value 141 is 'a' 534 and the "other representation" is '\141'. The "other representation" 535 is program language dependent. */ 536 537 #define PRINT_LITERAL_FORM(c) \ 538 ((c) >= 0x20 \ 539 && ((c) < 0x7F || (c) >= 0xA0) \ 540 && (!sevenbit_strings || (c) < 0x80)) 541 542 /* Type predicates */ 543 544 extern int pointer_type (struct type *); 545 546 /* Error messages */ 547 548 extern void range_error (const char *, ...) ATTRIBUTE_PRINTF (1, 2); 549 550 /* Data: Does this value represent "truth" to the current language? */ 551 552 extern int value_true (struct value *); 553 554 /* Misc: The string representing a particular enum language. */ 555 556 extern enum language language_enum (char *str); 557 558 extern const struct language_defn *language_def (enum language); 559 560 extern const char *language_str (enum language); 561 562 /* Add a language to the set known by GDB (at initialization time). */ 563 564 extern void add_language (const struct language_defn *); 565 566 /* Check for a language-specific trampoline. */ 567 568 extern CORE_ADDR skip_language_trampoline (struct frame_info *, CORE_ADDR pc); 569 570 /* Return demangled language symbol, or NULL. */ 571 extern char *language_demangle (const struct language_defn *current_language, 572 const char *mangled, int options); 573 574 /* A wrapper for la_sniff_from_mangled_name. The arguments and result 575 are as for the method. */ 576 577 extern int language_sniff_from_mangled_name (const struct language_defn *lang, 578 const char *mangled, 579 char **demangled); 580 581 /* Return class name from physname, or NULL. */ 582 extern char *language_class_name_from_physname (const struct language_defn *, 583 const char *physname); 584 585 /* Splitting strings into words. */ 586 extern const char *default_word_break_characters (void); 587 588 /* Print the index of an array element using the C99 syntax. */ 589 extern void default_print_array_index (struct value *index_value, 590 struct ui_file *stream, 591 const struct value_print_options *options); 592 593 /* Return non-zero if TYPE should be passed (and returned) by 594 reference at the language level. */ 595 int language_pass_by_reference (struct type *type); 596 597 /* Return zero; by default, types are passed by value at the language 598 level. The target ABI may pass or return some structs by reference 599 independent of this. */ 600 int default_pass_by_reference (struct type *type); 601 602 /* The default implementation of la_print_typedef. */ 603 void default_print_typedef (struct type *type, struct symbol *new_symbol, 604 struct ui_file *stream); 605 606 void default_get_string (struct value *value, gdb_byte **buffer, int *length, 607 struct type **char_type, const char **charset); 608 609 void c_get_string (struct value *value, gdb_byte **buffer, int *length, 610 struct type **char_type, const char **charset); 611 612 #endif /* defined (LANGUAGE_H) */ 613