gdb/language.h

   1 /* Source-language-related definitions for GDB.
   2
   3    Copyright (C) 1991-2018 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 #include "expression.h"
  29
  30 /* Forward decls for prototypes.  */
  31 struct value;
  32 struct objfile;
  33 struct frame_info;
  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 struct completion_match_for_lcd;
  41
  42 #define MAX_FORTRAN_DIMS  7     /* Maximum number of F77 array dims.  */
  43
  44 /* range_mode ==
  45    range_mode_auto:   range_check set automatically to default of language.
  46    range_mode_manual: range_check set manually by user.  */
  47
  48 extern enum range_mode
  49   {
  50     range_mode_auto, range_mode_manual
  51   }
  52 range_mode;
  53
  54 /* range_check ==
  55    range_check_on:    Ranges are checked in GDB expressions, producing errors.
  56    range_check_warn:  Ranges are checked, producing warnings.
  57    range_check_off:   Ranges are not checked in GDB expressions.  */
  58
  59 extern enum range_check
  60   {
  61     range_check_off, range_check_warn, range_check_on
  62   }
  63 range_check;
  64
  65 /* case_mode ==
  66    case_mode_auto:   case_sensitivity set upon selection of scope.
  67    case_mode_manual: case_sensitivity set only by user.  */
  68
  69 extern enum case_mode
  70   {
  71     case_mode_auto, case_mode_manual
  72   }
  73 case_mode;
  74
  75 /* array_ordering ==
  76    array_row_major:     Arrays are in row major order.
  77    array_column_major:  Arrays are in column major order.  */
  78
  79 extern enum array_ordering
  80   {
  81     array_row_major, array_column_major
  82   }
  83 array_ordering;
  84
  85
  86 /* case_sensitivity ==
  87    case_sensitive_on:   Case sensitivity in name matching is used.
  88    case_sensitive_off:  Case sensitivity in name matching is not used.  */
  89
  90 extern enum case_sensitivity
  91   {
  92     case_sensitive_on, case_sensitive_off
  93   }
  94 case_sensitivity;
  95
  96
  97 /* macro_expansion ==
  98    macro_expansion_no:  No macro expansion is available.
  99    macro_expansion_c:   C-like macro expansion is available.  */
 100
 101 enum macro_expansion
 102   {
 103     macro_expansion_no, macro_expansion_c
 104   };
 105
 106 \f
 107 /* Per architecture (OS/ABI) language information.  */
 108
 109 struct language_arch_info
 110 {
 111   /* Its primitive types.  This is a vector ended by a NULL pointer.
 112      These types can be specified by name in parsing types in
 113      expressions, regardless of whether the program being debugged
 114      actually defines such a type.  */
 115   struct type **primitive_type_vector;
 116
 117   /* Symbol wrappers around primitive_type_vector, so that the symbol lookup
 118      machinery can return them.  */
 119   struct symbol **primitive_type_symbols;
 120
 121   /* Type of elements of strings.  */
 122   struct type *string_char_type;
 123
 124   /* Symbol name of type to use as boolean type, if defined.  */
 125   const char *bool_type_symbol;
 126   /* Otherwise, this is the default boolean builtin type.  */
 127   struct type *bool_type_default;
 128 };
 129
 130 /* Structure tying together assorted information about a language.  */
 131
 132 struct language_defn
 133   {
 134     /* Name of the language.  */
 135
 136     const char *la_name;
 137
 138     /* Natural or official name of the language.  */
 139
 140     const char *la_natural_name;
 141
 142     /* its symtab language-enum (defs.h).  */
 143
 144     enum language la_language;
 145
 146     /* Default range checking.  */
 147
 148     enum range_check la_range_check;
 149
 150     /* Default case sensitivity.  */
 151     enum case_sensitivity la_case_sensitivity;
 152
 153     /* Multi-dimensional array ordering.  */
 154     enum array_ordering la_array_ordering;
 155
 156     /* Style of macro expansion, if any, supported by this language.  */
 157     enum macro_expansion la_macro_expansion;
 158
 159     /* A NULL-terminated array of file extensions for this language.
 160        The extension must include the ".", like ".c".  If this
 161        language doesn't need to provide any filename extensions, this
 162        may be NULL.  */
 163
 164     const char *const *la_filename_extensions;
 165
 166     /* Definitions related to expression printing, prefixifying, and
 167        dumping.  */
 168
 169     const struct exp_descriptor *la_exp_desc;
 170
 171     /* Parser function.  */
 172
 173     int (*la_parser) (struct parser_state *);
 174
 175     /* Given an expression *EXPP created by prefixifying the result of
 176        la_parser, perform any remaining processing necessary to complete
 177        its translation.  *EXPP may change; la_post_parser is responsible
 178        for releasing its previous contents, if necessary.  If
 179        VOID_CONTEXT_P, then no value is expected from the expression.  */
 180
 181     void (*la_post_parser) (expression_up *expp, int void_context_p);
 182
 183     void (*la_printchar) (int ch, struct type *chtype,
 184                           struct ui_file * stream);
 185
 186     void (*la_printstr) (struct ui_file * stream, struct type *elttype,
 187                          const gdb_byte *string, unsigned int length,
 188                          const char *encoding, int force_ellipses,
 189                          const struct value_print_options *);
 190
 191     void (*la_emitchar) (int ch, struct type *chtype,
 192                          struct ui_file * stream, int quoter);
 193
 194     /* Print a type using syntax appropriate for this language.  */
 195
 196     void (*la_print_type) (struct type *, const char *, struct ui_file *, int,
 197                            int, const struct type_print_options *);
 198
 199     /* Print a typedef using syntax appropriate for this language.
 200        TYPE is the underlying type.  NEW_SYMBOL is the symbol naming
 201        the type.  STREAM is the output stream on which to print.  */
 202
 203     void (*la_print_typedef) (struct type *type, struct symbol *new_symbol,
 204                               struct ui_file *stream);
 205
 206     /* Print a value using syntax appropriate for this language.
 207
 208        TYPE is the type of the sub-object to be printed.
 209
 210        EMBEDDED_OFFSET is the offset into the outermost object of the
 211        sub-object represented by TYPE.  This is the object which this
 212        call should print.  Note that the enclosing type is not
 213        available.
 214
 215        ADDRESS is the address in the inferior of the enclosing object.
 216
 217        STREAM is the stream on which the value is to be printed.
 218
 219        RECURSE is the recursion depth.  It is zero-based.
 220
 221        OPTIONS are the formatting options to be used when
 222        printing.  */
 223
 224     void (*la_val_print) (struct type *type,
 225                           int embedded_offset, CORE_ADDR address,
 226                           struct ui_file *stream, int recurse,
 227                           struct value *val,
 228                           const struct value_print_options *options);
 229
 230     /* Print a top-level value using syntax appropriate for this language.  */
 231
 232     void (*la_value_print) (struct value *, struct ui_file *,
 233                             const struct value_print_options *);
 234
 235     /* Given a symbol VAR, the corresponding block VAR_BLOCK (if any) and a
 236        stack frame id FRAME, read the value of the variable and return (pointer
 237        to a) struct value containing the value.
 238
 239        VAR_BLOCK is needed if there's a possibility for VAR to be outside
 240        FRAME.  This is what happens if FRAME correspond to a nested function
 241        and VAR is defined in the outer function.  If callers know that VAR is
 242        located in FRAME or is global/static, NULL can be passed as VAR_BLOCK.
 243
 244        Throw an error if the variable cannot be found.  */
 245
 246     struct value *(*la_read_var_value) (struct symbol *var,
 247                                         const struct block *var_block,
 248                                         struct frame_info *frame);
 249
 250     /* PC is possibly an unknown languages trampoline.
 251        If that PC falls in a trampoline belonging to this language,
 252        return the address of the first pc in the real function, or 0
 253        if it isn't a language tramp for this language.  */
 254     CORE_ADDR (*skip_trampoline) (struct frame_info *, CORE_ADDR);
 255
 256     /* Now come some hooks for lookup_symbol.  */
 257
 258     /* If this is non-NULL, specifies the name that of the implicit
 259        local variable that refers to the current object instance.  */
 260
 261     const char *la_name_of_this;
 262
 263     /* True if the symbols names should be stored in GDB's data structures
 264        for minimal/partial/full symbols using their linkage (aka mangled)
 265        form; false if the symbol names should be demangled first.
 266
 267        Most languages implement symbol lookup by comparing the demangled
 268        names, in which case it is advantageous to store that information
 269        already demangled, and so would set this field to false.
 270
 271        On the other hand, some languages have opted for doing symbol
 272        lookups by comparing mangled names instead, for reasons usually
 273        specific to the language.  Those languages should set this field
 274        to true.
 275
 276        And finally, other languages such as C or Asm do not have
 277        the concept of mangled vs demangled name, so those languages
 278        should set this field to true as well, to prevent any accidental
 279        demangling through an unrelated language's demangler.  */
 280
 281     const bool la_store_sym_names_in_linkage_form_p;
 282
 283     /* This is a function that lookup_symbol will call when it gets to
 284        the part of symbol lookup where C looks up static and global
 285        variables.  */
 286
 287     struct block_symbol (*la_lookup_symbol_nonlocal)
 288       (const struct language_defn *,
 289        const char *,
 290        const struct block *,
 291        const domain_enum);
 292
 293     /* Find the definition of the type with the given name.  */
 294     struct type *(*la_lookup_transparent_type) (const char *);
 295
 296     /* Return demangled language symbol, or NULL.  */
 297     char *(*la_demangle) (const char *mangled, int options);
 298
 299     /* Demangle a symbol according to this language's rules.  Unlike
 300        la_demangle, this does not take any options.
 301
 302        *DEMANGLED will be set by this function.
 303
 304        If this function returns 0, then *DEMANGLED must always be set
 305        to NULL.
 306
 307        If this function returns 1, the implementation may set this to
 308        a xmalloc'd string holding the demangled form.  However, it is
 309        not required to.  The string, if any, is owned by the caller.
 310
 311        The resulting string should be of the form that will be
 312        installed into a symbol.  */
 313     int (*la_sniff_from_mangled_name) (const char *mangled, char **demangled);
 314
 315     /* Return class name of a mangled method name or NULL.  */
 316     char *(*la_class_name_from_physname) (const char *physname);
 317
 318     /* Table for printing expressions.  */
 319
 320     const struct op_print *la_op_print_tab;
 321
 322     /* Zero if the language has first-class arrays.  True if there are no
 323        array values, and array objects decay to pointers, as in C.  */
 324
 325     char c_style_arrays;
 326
 327     /* Index to use for extracting the first element of a string.  */
 328     char string_lower_bound;
 329
 330     /* The list of characters forming word boundaries.  */
 331     const char *(*la_word_break_characters) (void);
 332
 333     /* Add to the completion tracker all symbols which are possible
 334        completions for TEXT.  WORD is the entire command on which the
 335        completion is being made.  If CODE is TYPE_CODE_UNDEF, then all
 336        symbols should be examined; otherwise, only STRUCT_DOMAIN
 337        symbols whose type has a code of CODE should be matched.  */
 338     void (*la_collect_symbol_completion_matches)
 339       (completion_tracker &tracker,
 340        complete_symbol_mode mode,
 341        symbol_name_match_type match_type,
 342        const char *text,
 343        const char *word,
 344        enum type_code code);
 345
 346     /* The per-architecture (OS/ABI) language information.  */
 347     void (*la_language_arch_info) (struct gdbarch *,
 348                                    struct language_arch_info *);
 349
 350     /* Print the index of an element of an array.  */
 351     void (*la_print_array_index) (struct value *index_value,
 352                                   struct ui_file *stream,
 353                                   const struct value_print_options *options);
 354
 355     /* Return non-zero if TYPE should be passed (and returned) by
 356        reference at the language level.  */
 357     int (*la_pass_by_reference) (struct type *type);
 358
 359     /* Obtain a string from the inferior, storing it in a newly allocated
 360        buffer in BUFFER, which should be freed by the caller.  If the
 361        in- and out-parameter *LENGTH is specified at -1, the string is
 362        read until a null character of the appropriate width is found -
 363        otherwise the string is read to the length of characters specified.
 364        On completion, *LENGTH will hold the size of the string in characters.
 365        If a *LENGTH of -1 was specified it will count only actual
 366        characters, excluding any eventual terminating null character.
 367        Otherwise *LENGTH will include all characters - including any nulls.
 368        CHARSET will hold the encoding used in the string.  */
 369     void (*la_get_string) (struct value *value, gdb_byte **buffer, int *length,
 370                            struct type **chartype, const char **charset);
 371
 372     /* Return an expression that can be used for a location
 373        watchpoint.  TYPE is a pointer type that points to the memory
 374        to watch, and ADDR is the address of the watched memory.  */
 375     gdb::unique_xmalloc_ptr<char> (*la_watch_location_expression)
 376          (struct type *type, CORE_ADDR addr);
 377
 378     /* Return a pointer to the function that should be used to match a
 379        symbol name against LOOKUP_NAME, according to this language's
 380        rules.  The matching algorithm depends on LOOKUP_NAME.  For
 381        example, on Ada, the matching algorithm depends on the symbol
 382        name (wild/full/verbatim matching), and on whether we're doing
 383        a normal lookup or a completion match lookup.
 384
 385        This field may be NULL, in which case
 386        default_symbol_name_matcher is used to perform the
 387        matching.  */
 388     symbol_name_matcher_ftype *(*la_get_symbol_name_matcher)
 389       (const lookup_name_info &);
 390
 391     /* Find all symbols in the current program space matching NAME in
 392        DOMAIN, according to this language's rules.
 393
 394        The search is done in BLOCK only.
 395        The caller is responsible for iterating up through superblocks
 396        if desired.
 397
 398        For each one, call CALLBACK with the symbol.  If CALLBACK
 399        returns false, the iteration ends at that point.
 400
 401        This field may not be NULL.  If the language does not need any
 402        special processing here, 'iterate_over_symbols' should be
 403        used as the definition.  */
 404     void (*la_iterate_over_symbols)
 405       (const struct block *block, const lookup_name_info &name,
 406        domain_enum domain,
 407        gdb::function_view<symbol_found_callback_ftype> callback);
 408
 409     /* Hash the given symbol search name.  Use
 410        default_search_name_hash if no special treatment is
 411        required.  */
 412     unsigned int (*la_search_name_hash) (const char *name);
 413
 414     /* Various operations on varobj.  */
 415     const struct lang_varobj_ops *la_varobj_ops;
 416
 417     /* If this language allows compilation from the gdb command line,
 418        this method should be non-NULL.  When called it should return
 419        an instance of struct gcc_context appropriate to the language.
 420        When defined this method must never return NULL; instead it
 421        should throw an exception on failure.  The returned compiler
 422        instance is owned by its caller and must be deallocated by
 423        calling its 'destroy' method.  */
 424
 425     struct compile_instance *(*la_get_compile_instance) (void);
 426
 427     /* This method must be defined if 'la_get_gcc_context' is defined.
 428        If 'la_get_gcc_context' is not defined, then this method is
 429        ignored.
 430
 431        This takes the user-supplied text and returns a new bit of code
 432        to compile.
 433
 434        INST is the compiler instance being used.
 435        INPUT is the user's input text.
 436        GDBARCH is the architecture to use.
 437        EXPR_BLOCK is the block in which the expression is being
 438        parsed.
 439        EXPR_PC is the PC at which the expression is being parsed.  */
 440
 441     std::string (*la_compute_program) (struct compile_instance *inst,
 442                                        const char *input,
 443                                        struct gdbarch *gdbarch,
 444                                        const struct block *expr_block,
 445                                        CORE_ADDR expr_pc);
 446
 447     /* Add fields above this point, so the magic number is always last.  */
 448     /* Magic number for compat checking.  */
 449
 450     long la_magic;
 451
 452   };
 453
 454 #define LANG_MAGIC      910823L
 455
 456 /* Pointer to the language_defn for our current language.  This pointer
 457    always points to *some* valid struct; it can be used without checking
 458    it for validity.
 459
 460    The current language affects expression parsing and evaluation
 461    (FIXME: it might be cleaner to make the evaluation-related stuff
 462    separate exp_opcodes for each different set of semantics.  We
 463    should at least think this through more clearly with respect to
 464    what happens if the language is changed between parsing and
 465    evaluation) and printing of things like types and arrays.  It does
 466    *not* affect symbol-reading-- each source file in a symbol-file has
 467    its own language and we should keep track of that regardless of the
 468    language when symbols are read.  If we want some manual setting for
 469    the language of symbol files (e.g. detecting when ".c" files are
 470    C++), it should be a separate setting from the current_language.  */
 471
 472 extern const struct language_defn *current_language;
 473
 474 /* Pointer to the language_defn expected by the user, e.g. the language
 475    of main(), or the language we last mentioned in a message, or C.  */
 476
 477 extern const struct language_defn *expected_language;
 478
 479 /* language_mode ==
 480    language_mode_auto:   current_language automatically set upon selection
 481    of scope (e.g. stack frame)
 482    language_mode_manual: current_language set only by user.  */
 483
 484 extern enum language_mode
 485   {
 486     language_mode_auto, language_mode_manual
 487   }
 488 language_mode;
 489
 490 struct type *language_bool_type (const struct language_defn *l,
 491                                  struct gdbarch *gdbarch);
 492
 493 struct type *language_string_char_type (const struct language_defn *l,
 494                                         struct gdbarch *gdbarch);
 495
 496 /* Look up type NAME in language L, and return its definition for architecture
 497    GDBARCH.  Returns NULL if not found.  */
 498
 499 struct type *language_lookup_primitive_type (const struct language_defn *l,
 500                                              struct gdbarch *gdbarch,
 501                                              const char *name);
 502
 503 /* Wrapper around language_lookup_primitive_type to return the
 504    corresponding symbol.  */
 505
 506 struct symbol *
 507   language_lookup_primitive_type_as_symbol (const struct language_defn *l,
 508                                             struct gdbarch *gdbarch,
 509                                             const char *name);
 510
 511 \f
 512 /* These macros define the behaviour of the expression
 513    evaluator.  */
 514
 515 /* Should we range check values against the domain of their type?  */
 516 #define RANGE_CHECK (range_check != range_check_off)
 517
 518 /* "cast" really means conversion.  */
 519 /* FIXME -- should be a setting in language_defn.  */
 520 #define CAST_IS_CONVERSION(LANG) ((LANG)->la_language == language_c  || \
 521                                   (LANG)->la_language == language_cplus || \
 522                                   (LANG)->la_language == language_objc)
 523
 524 extern void language_info (int);
 525
 526 extern enum language set_language (enum language);
 527 \f
 528
 529 /* This page contains functions that return things that are
 530    specific to languages.  Each of these functions is based on
 531    the current setting of working_lang, which the user sets
 532    with the "set language" command.  */
 533
 534 #define LA_PRINT_TYPE(type,varstring,stream,show,level,flags)           \
 535   (current_language->la_print_type(type,varstring,stream,show,level,flags))
 536
 537 #define LA_PRINT_TYPEDEF(type,new_symbol,stream) \
 538   (current_language->la_print_typedef(type,new_symbol,stream))
 539
 540 #define LA_VALUE_PRINT(val,stream,options) \
 541   (current_language->la_value_print(val,stream,options))
 542
 543 #define LA_PRINT_CHAR(ch, type, stream) \
 544   (current_language->la_printchar(ch, type, stream))
 545 #define LA_PRINT_STRING(stream, elttype, string, length, encoding, force_ellipses, options) \
 546   (current_language->la_printstr(stream, elttype, string, length, \
 547                                  encoding, force_ellipses,options))
 548 #define LA_EMIT_CHAR(ch, type, stream, quoter) \
 549   (current_language->la_emitchar(ch, type, stream, quoter))
 550 #define LA_GET_STRING(value, buffer, length, chartype, encoding) \
 551   (current_language->la_get_string(value, buffer, length, chartype, encoding))
 552
 553 #define LA_PRINT_ARRAY_INDEX(index_value, stream, options) \
 554   (current_language->la_print_array_index(index_value, stream, options))
 555
 556 #define LA_ITERATE_OVER_SYMBOLS(BLOCK, NAME, DOMAIN, CALLBACK) \
 557   (current_language->la_iterate_over_symbols (BLOCK, NAME, DOMAIN, CALLBACK))
 558
 559 /* Test a character to decide whether it can be printed in literal form
 560    or needs to be printed in another representation.  For example,
 561    in C the literal form of the character with octal value 141 is 'a'
 562    and the "other representation" is '\141'.  The "other representation"
 563    is program language dependent.  */
 564
 565 #define PRINT_LITERAL_FORM(c)           \
 566   ((c) >= 0x20                          \
 567    && ((c) < 0x7F || (c) >= 0xA0)       \
 568    && (!sevenbit_strings || (c) < 0x80))
 569
 570 /* Type predicates */
 571
 572 extern int pointer_type (struct type *);
 573
 574 /* Error messages */
 575
 576 extern void range_error (const char *, ...) ATTRIBUTE_PRINTF (1, 2);
 577
 578 /* Data:  Does this value represent "truth" to the current language?  */
 579
 580 extern int value_true (struct value *);
 581
 582 /* Misc:  The string representing a particular enum language.  */
 583
 584 extern enum language language_enum (const char *str);
 585
 586 extern const struct language_defn *language_def (enum language);
 587
 588 extern const char *language_str (enum language);
 589
 590 /* Check for a language-specific trampoline.  */
 591
 592 extern CORE_ADDR skip_language_trampoline (struct frame_info *, CORE_ADDR pc);
 593
 594 /* Return demangled language symbol, or NULL.  */
 595 extern char *language_demangle (const struct language_defn *current_language,
 596                                 const char *mangled, int options);
 597
 598 /* A wrapper for la_sniff_from_mangled_name.  The arguments and result
 599    are as for the method.  */
 600
 601 extern int language_sniff_from_mangled_name (const struct language_defn *lang,
 602                                              const char *mangled,
 603                                              char **demangled);
 604
 605 /* Return class name from physname, or NULL.  */
 606 extern char *language_class_name_from_physname (const struct language_defn *,
 607                                                 const char *physname);
 608
 609 /* Splitting strings into words.  */
 610 extern const char *default_word_break_characters (void);
 611
 612 /* Print the index of an array element using the C99 syntax.  */
 613 extern void default_print_array_index (struct value *index_value,
 614                                        struct ui_file *stream,
 615                                        const struct value_print_options *options);
 616
 617 /* Return non-zero if TYPE should be passed (and returned) by
 618    reference at the language level.  */
 619 int language_pass_by_reference (struct type *type);
 620
 621 /* Return zero; by default, types are passed by value at the language
 622    level.  The target ABI may pass or return some structs by reference
 623    independent of this.  */
 624 int default_pass_by_reference (struct type *type);
 625
 626 /* The default implementation of la_print_typedef.  */
 627 void default_print_typedef (struct type *type, struct symbol *new_symbol,
 628                             struct ui_file *stream);
 629
 630 void default_get_string (struct value *value, gdb_byte **buffer, int *length,
 631                          struct type **char_type, const char **charset);
 632
 633 /* Default name hashing function.  */
 634
 635 /* Produce an unsigned hash value from SEARCH_NAME that is consistent
 636    with strcmp_iw, strcmp, and, at least on Ada symbols, wild_match.
 637    That is, two identifiers equivalent according to any of those three
 638    comparison operators hash to the same value.  */
 639 extern unsigned int default_search_name_hash (const char *search_name);
 640
 641 void c_get_string (struct value *value, gdb_byte **buffer, int *length,
 642                    struct type **char_type, const char **charset);
 643
 644 /* The default implementation of la_symbol_name_matcher.  Matches with
 645    strncmp_iw.  */
 646 extern bool default_symbol_name_matcher
 647   (const char *symbol_search_name,
 648    const lookup_name_info &lookup_name,
 649    completion_match_result *comp_match_res);
 650
 651 /* Get LANG's symbol_name_matcher method for LOOKUP_NAME.  Returns
 652    default_symbol_name_matcher if not set.  LANG is used as a hint;
 653    the function may ignore it depending on the current language and
 654    LOOKUP_NAME.  Specifically, if the current language is Ada, this
 655    may return an Ada matcher regardless of LANG.  */
 656 symbol_name_matcher_ftype *get_symbol_name_matcher
 657   (const language_defn *lang, const lookup_name_info &lookup_name);
 658
 659 /* The languages supported by GDB.  */
 660
 661 extern const struct language_defn auto_language_defn;
 662 extern const struct language_defn unknown_language_defn;
 663 extern const struct language_defn minimal_language_defn;
 664
 665 extern const struct language_defn ada_language_defn;
 666 extern const struct language_defn asm_language_defn;
 667 extern const struct language_defn c_language_defn;
 668 extern const struct language_defn cplus_language_defn;
 669 extern const struct language_defn d_language_defn;
 670 extern const struct language_defn f_language_defn;
 671 extern const struct language_defn go_language_defn;
 672 extern const struct language_defn m2_language_defn;
 673 extern const struct language_defn objc_language_defn;
 674 extern const struct language_defn opencl_language_defn;
 675 extern const struct language_defn pascal_language_defn;
 676 extern const struct language_defn rust_language_defn;
 677
 678 /* Save the current language and restore it upon destruction.  */
 679
 680 class scoped_restore_current_language
 681 {
 682 public:
 683
 684   explicit scoped_restore_current_language ()
 685     : m_lang (current_language->la_language)
 686   {
 687   }
 688
 689   ~scoped_restore_current_language ()
 690   {
 691     set_language (m_lang);
 692   }
 693
 694   scoped_restore_current_language (const scoped_restore_current_language &)
 695       = delete;
 696   scoped_restore_current_language &operator=
 697       (const scoped_restore_current_language &) = delete;
 698
 699 private:
 700
 701   enum language m_lang;
 702 };
 703
 704 #endif /* defined (LANGUAGE_H) */