gdb/language.h

   1 /* Source-language-related definitions for GDB.
   2
   3    Copyright (C) 1991-1995, 1998-2000, 2003-2004, 2007-2012 Free
   4    Software Foundation, Inc.
   5
   6    Contributed by the Department of Computer Science at the State University
   7    of New York at Buffalo.
   8
   9    This file is part of GDB.
  10
  11    This program is free software; you can redistribute it and/or modify
  12    it under the terms of the GNU General Public License as published by
  13    the Free Software Foundation; either version 3 of the License, or
  14    (at your option) any later version.
  15
  16    This program is distributed in the hope that it will be useful,
  17    but WITHOUT ANY WARRANTY; without even the implied warranty of
  18    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  19    GNU General Public License for more details.
  20
  21    You should have received a copy of the GNU General Public License
  22    along with this program.  If not, see <http://www.gnu.org/licenses/>.  */
  23
  24 #if !defined (LANGUAGE_H)
  25 #define LANGUAGE_H 1
  26
  27 /* Forward decls for prototypes.  */
  28 struct value;
  29 struct objfile;
  30 struct frame_info;
  31 struct expression;
  32 struct ui_file;
  33 struct value_print_options;
  34
  35 #define MAX_FORTRAN_DIMS  7     /* Maximum number of F77 array dims.  */
  36
  37 /* range_mode ==
  38    range_mode_auto:   range_check set automatically to default of language.
  39    range_mode_manual: range_check set manually by user.  */
  40
  41 extern enum range_mode
  42   {
  43     range_mode_auto, range_mode_manual
  44   }
  45 range_mode;
  46
  47 /* range_check ==
  48    range_check_on:    Ranges are checked in GDB expressions, producing errors.
  49    range_check_warn:  Ranges are checked, producing warnings.
  50    range_check_off:   Ranges are not checked in GDB expressions.  */
  51
  52 extern enum range_check
  53   {
  54     range_check_off, range_check_warn, range_check_on
  55   }
  56 range_check;
  57
  58 /* type_mode ==
  59    type_mode_auto:   type_check set automatically to default of language.
  60    type_mode_manual: type_check set manually by user.  */
  61
  62 extern enum type_mode
  63   {
  64     type_mode_auto, type_mode_manual
  65   }
  66 type_mode;
  67
  68 /* type_check ==
  69    type_check_on:    Types are checked in GDB expressions, producing errors.
  70    type_check_warn:  Types are checked, producing warnings.
  71    type_check_off:   Types are not checked in GDB expressions.  */
  72
  73 extern enum type_check
  74   {
  75     type_check_off, type_check_warn, type_check_on
  76   }
  77 type_check;
  78
  79 /* case_mode ==
  80    case_mode_auto:   case_sensitivity set upon selection of scope.
  81    case_mode_manual: case_sensitivity set only by user.  */
  82
  83 extern enum case_mode
  84   {
  85     case_mode_auto, case_mode_manual
  86   }
  87 case_mode;
  88
  89 /* array_ordering ==
  90    array_row_major:     Arrays are in row major order.
  91    array_column_major:  Arrays are in column major order.  */
  92
  93 extern enum array_ordering
  94   {
  95     array_row_major, array_column_major
  96   }
  97 array_ordering;
  98
  99
 100 /* case_sensitivity ==
 101    case_sensitive_on:   Case sensitivity in name matching is used.
 102    case_sensitive_off:  Case sensitivity in name matching is not used.  */
 103
 104 extern enum case_sensitivity
 105   {
 106     case_sensitive_on, case_sensitive_off
 107   }
 108 case_sensitivity;
 109
 110
 111 /* macro_expansion ==
 112    macro_expansion_no:  No macro expansion is available.
 113    macro_expansion_c:   C-like macro expansion is available.  */
 114
 115 enum macro_expansion
 116   {
 117     macro_expansion_no, macro_expansion_c
 118   };
 119
 120 \f
 121 /* Per architecture (OS/ABI) language information.  */
 122
 123 struct language_arch_info
 124 {
 125   /* Its primitive types.  This is a vector ended by a NULL pointer.
 126      These types can be specified by name in parsing types in
 127      expressions, regardless of whether the program being debugged
 128      actually defines such a type.  */
 129   struct type **primitive_type_vector;
 130   /* Type of elements of strings.  */
 131   struct type *string_char_type;
 132
 133   /* Symbol name of type to use as boolean type, if defined.  */
 134   const char *bool_type_symbol;
 135   /* Otherwise, this is the default boolean builtin type.  */
 136   struct type *bool_type_default;
 137 };
 138
 139 /* A pointer to a function expected to return nonzero if
 140    SYMBOL_SEARCH_NAME matches the given LOOKUP_NAME.
 141
 142    SYMBOL_SEARCH_NAME should be a symbol's "search" name.
 143    LOOKUP_NAME should be the name of an entity after it has been
 144    transformed for lookup.  */
 145
 146 typedef int (*symbol_name_match_p_ftype) (const char *symbol_search_name,
 147                                           const char *lookup_name);
 148
 149 /* Structure tying together assorted information about a language.  */
 150
 151 struct language_defn
 152   {
 153     /* Name of the language.  */
 154
 155     char *la_name;
 156
 157     /* its symtab language-enum (defs.h).  */
 158
 159     enum language la_language;
 160
 161     /* Default range checking.  */
 162
 163     enum range_check la_range_check;
 164
 165     /* Default type checking.  */
 166
 167     enum type_check la_type_check;
 168
 169     /* Default case sensitivity.  */
 170     enum case_sensitivity la_case_sensitivity;
 171
 172     /* Multi-dimensional array ordering.  */
 173     enum array_ordering la_array_ordering;
 174
 175     /* Style of macro expansion, if any, supported by this language.  */
 176     enum macro_expansion la_macro_expansion;
 177
 178     /* Definitions related to expression printing, prefixifying, and
 179        dumping.  */
 180
 181     const struct exp_descriptor *la_exp_desc;
 182
 183     /* Parser function.  */
 184
 185     int (*la_parser) (void);
 186
 187     /* Parser error function.  */
 188
 189     void (*la_error) (char *);
 190
 191     /* Given an expression *EXPP created by prefixifying the result of
 192        la_parser, perform any remaining processing necessary to complete
 193        its translation.  *EXPP may change; la_post_parser is responsible
 194        for releasing its previous contents, if necessary.  If
 195        VOID_CONTEXT_P, then no value is expected from the expression.  */
 196
 197     void (*la_post_parser) (struct expression ** expp, int void_context_p);
 198
 199     void (*la_printchar) (int ch, struct type *chtype,
 200                           struct ui_file * stream);
 201
 202     void (*la_printstr) (struct ui_file * stream, struct type *elttype,
 203                          const gdb_byte *string, unsigned int length,
 204                          const char *encoding, int force_ellipses,
 205                          const struct value_print_options *);
 206
 207     void (*la_emitchar) (int ch, struct type *chtype,
 208                          struct ui_file * stream, int quoter);
 209
 210     /* Print a type using syntax appropriate for this language.  */
 211
 212     void (*la_print_type) (struct type *, const char *, struct ui_file *, int,
 213                            int);
 214
 215     /* Print a typedef using syntax appropriate for this language.
 216        TYPE is the underlying type.  NEW_SYMBOL is the symbol naming
 217        the type.  STREAM is the output stream on which to print.  */
 218
 219     void (*la_print_typedef) (struct type *type, struct symbol *new_symbol,
 220                               struct ui_file *stream);
 221
 222     /* Print a value using syntax appropriate for this language.
 223
 224        TYPE is the type of the sub-object to be printed.
 225
 226        CONTENTS holds the bits of the value.  This holds the entire
 227        enclosing object.
 228
 229        EMBEDDED_OFFSET is the offset into the outermost object of the
 230        sub-object represented by TYPE.  This is the object which this
 231        call should print.  Note that the enclosing type is not
 232        available.
 233
 234        ADDRESS is the address in the inferior of the enclosing object.
 235
 236        STREAM is the stream on which the value is to be printed.
 237
 238        RECURSE is the recursion depth.  It is zero-based.
 239
 240        OPTIONS are the formatting options to be used when
 241        printing.  */
 242
 243     int (*la_val_print) (struct type *type,
 244                          const gdb_byte *contents,
 245                          int embedded_offset, CORE_ADDR address,
 246                          struct ui_file *stream, int recurse,
 247                          const struct value *val,
 248                          const struct value_print_options *options);
 249
 250     /* Print a top-level value using syntax appropriate for this language.  */
 251
 252     int (*la_value_print) (struct value *, struct ui_file *,
 253                            const struct value_print_options *);
 254
 255     /* PC is possibly an unknown languages trampoline.
 256        If that PC falls in a trampoline belonging to this language,
 257        return the address of the first pc in the real function, or 0
 258        if it isn't a language tramp for this language.  */
 259     CORE_ADDR (*skip_trampoline) (struct frame_info *, CORE_ADDR);
 260
 261     /* Now come some hooks for lookup_symbol.  */
 262
 263     /* If this is non-NULL, specifies the name that of the implicit
 264        local variable that refers to the current object instance.  */
 265
 266     char *la_name_of_this;
 267
 268     /* This is a function that lookup_symbol will call when it gets to
 269        the part of symbol lookup where C looks up static and global
 270        variables.  */
 271
 272     struct symbol *(*la_lookup_symbol_nonlocal) (const char *,
 273                                                  const struct block *,
 274                                                  const domain_enum);
 275
 276     /* Find the definition of the type with the given name.  */
 277     struct type *(*la_lookup_transparent_type) (const char *);
 278
 279     /* Return demangled language symbol, or NULL.  */
 280     char *(*la_demangle) (const char *mangled, int options);
 281
 282     /* Return class name of a mangled method name or NULL.  */
 283     char *(*la_class_name_from_physname) (const char *physname);
 284
 285     /* Table for printing expressions.  */
 286
 287     const struct op_print *la_op_print_tab;
 288
 289     /* Zero if the language has first-class arrays.  True if there are no
 290        array values, and array objects decay to pointers, as in C.  */
 291
 292     char c_style_arrays;
 293
 294     /* Index to use for extracting the first element of a string.  */
 295     char string_lower_bound;
 296
 297     /* The list of characters forming word boundaries.  */
 298     char *(*la_word_break_characters) (void);
 299
 300     /* Should return a NULL terminated array of all symbols which
 301        are possible completions for TEXT.  WORD is the entire command
 302        on which the completion is being made.  */
 303     char **(*la_make_symbol_completion_list) (char *text, char *word);
 304
 305     /* The per-architecture (OS/ABI) language information.  */
 306     void (*la_language_arch_info) (struct gdbarch *,
 307                                    struct language_arch_info *);
 308
 309     /* Print the index of an element of an array.  */
 310     void (*la_print_array_index) (struct value *index_value,
 311                                   struct ui_file *stream,
 312                                   const struct value_print_options *options);
 313
 314     /* Return non-zero if TYPE should be passed (and returned) by
 315        reference at the language level.  */
 316     int (*la_pass_by_reference) (struct type *type);
 317
 318     /* Obtain a string from the inferior, storing it in a newly allocated
 319        buffer in BUFFER, which should be freed by the caller.  If the
 320        in- and out-parameter *LENGTH is specified at -1, the string is
 321        read until a null character of the appropriate width is found -
 322        otherwise the string is read to the length of characters specified.
 323        On completion, *LENGTH will hold the size of the string in characters.
 324        If a *LENGTH of -1 was specified it will count only actual
 325        characters, excluding any eventual terminating null character.
 326        Otherwise *LENGTH will include all characters - including any nulls.
 327        CHARSET will hold the encoding used in the string.  */
 328     void (*la_get_string) (struct value *value, gdb_byte **buffer, int *length,
 329                            struct type **chartype, const char **charset);
 330
 331     /* Return a pointer to the function that should be used to match
 332        a symbol name against LOOKUP_NAME. This is mostly for languages
 333        such as Ada where the matching algorithm depends on LOOKUP_NAME.
 334
 335        This field may be NULL, in which case strcmp_iw will be used
 336        to perform the matching.  */
 337     symbol_name_match_p_ftype (*la_get_symbol_name_match_p)
 338       (const char *lookup_name);
 339
 340     /* Find all symbols in the current program space matching NAME in
 341        DOMAIN, according to this language's rules.
 342
 343        The search starts with BLOCK.  This function iterates upward
 344        through blocks.  When the outermost block has been finished,
 345        the function returns.
 346
 347        For each one, call CALLBACK with the symbol and the DATA
 348        argument.  If CALLBACK returns zero, the iteration ends at that
 349        point.
 350
 351        This field can be NULL, meaning that this language doesn't need
 352        any special code aside from ordinary searches of the symbol
 353        table.  */
 354     void (*la_iterate_over_symbols) (const struct block *block,
 355                                      const char *name,
 356                                      domain_enum domain,
 357                                      int (*callback) (struct symbol *, void *),
 358                                      void *data);
 359
 360     /* Add fields above this point, so the magic number is always last.  */
 361     /* Magic number for compat checking.  */
 362
 363     long la_magic;
 364
 365   };
 366
 367 #define LANG_MAGIC      910823L
 368
 369 /* Pointer to the language_defn for our current language.  This pointer
 370    always points to *some* valid struct; it can be used without checking
 371    it for validity.
 372
 373    The current language affects expression parsing and evaluation
 374    (FIXME: it might be cleaner to make the evaluation-related stuff
 375    separate exp_opcodes for each different set of semantics.  We
 376    should at least think this through more clearly with respect to
 377    what happens if the language is changed between parsing and
 378    evaluation) and printing of things like types and arrays.  It does
 379    *not* affect symbol-reading-- each source file in a symbol-file has
 380    its own language and we should keep track of that regardless of the
 381    language when symbols are read.  If we want some manual setting for
 382    the language of symbol files (e.g. detecting when ".c" files are
 383    C++), it should be a separate setting from the current_language.  */
 384
 385 extern const struct language_defn *current_language;
 386
 387 /* Pointer to the language_defn expected by the user, e.g. the language
 388    of main(), or the language we last mentioned in a message, or C.  */
 389
 390 extern const struct language_defn *expected_language;
 391
 392 /* language_mode ==
 393    language_mode_auto:   current_language automatically set upon selection
 394    of scope (e.g. stack frame)
 395    language_mode_manual: current_language set only by user.  */
 396
 397 extern enum language_mode
 398   {
 399     language_mode_auto, language_mode_manual
 400   }
 401 language_mode;
 402
 403 struct type *language_bool_type (const struct language_defn *l,
 404                                  struct gdbarch *gdbarch);
 405
 406 struct type *language_string_char_type (const struct language_defn *l,
 407                                         struct gdbarch *gdbarch);
 408
 409 struct type *language_lookup_primitive_type_by_name (const struct language_defn *l,
 410                                                      struct gdbarch *gdbarch,
 411                                                      const char *name);
 412
 413 \f
 414 /* These macros define the behaviour of the expression
 415    evaluator.  */
 416
 417 /* Should we strictly type check expressions?  */
 418 #define STRICT_TYPE (type_check != type_check_off)
 419
 420 /* Should we range check values against the domain of their type?  */
 421 #define RANGE_CHECK (range_check != range_check_off)
 422
 423 /* "cast" really means conversion.  */
 424 /* FIXME -- should be a setting in language_defn.  */
 425 #define CAST_IS_CONVERSION(LANG) ((LANG)->la_language == language_c  || \
 426                                   (LANG)->la_language == language_cplus || \
 427                                   (LANG)->la_language == language_objc)
 428
 429 extern void language_info (int);
 430
 431 extern enum language set_language (enum language);
 432 \f
 433
 434 /* This page contains functions that return things that are
 435    specific to languages.  Each of these functions is based on
 436    the current setting of working_lang, which the user sets
 437    with the "set language" command.  */
 438
 439 #define LA_PRINT_TYPE(type,varstring,stream,show,level) \
 440   (current_language->la_print_type(type,varstring,stream,show,level))
 441
 442 #define LA_PRINT_TYPEDEF(type,new_symbol,stream) \
 443   (current_language->la_print_typedef(type,new_symbol,stream))
 444
 445 #define LA_VAL_PRINT(type,valaddr,offset,addr,stream,val,recurse,options) \
 446   (current_language->la_val_print(type,valaddr,offset,addr,stream, \
 447                                   val,recurse,options))
 448 #define LA_VALUE_PRINT(val,stream,options) \
 449   (current_language->la_value_print(val,stream,options))
 450
 451 #define LA_PRINT_CHAR(ch, type, stream) \
 452   (current_language->la_printchar(ch, type, stream))
 453 #define LA_PRINT_STRING(stream, elttype, string, length, encoding, force_ellipses, options) \
 454   (current_language->la_printstr(stream, elttype, string, length, \
 455                                  encoding, force_ellipses,options))
 456 #define LA_EMIT_CHAR(ch, type, stream, quoter) \
 457   (current_language->la_emitchar(ch, type, stream, quoter))
 458 #define LA_GET_STRING(value, buffer, length, chartype, encoding) \
 459   (current_language->la_get_string(value, buffer, length, chartype, encoding))
 460
 461 #define LA_PRINT_ARRAY_INDEX(index_value, stream, options) \
 462   (current_language->la_print_array_index(index_value, stream, options))
 463
 464 #define LA_ITERATE_OVER_SYMBOLS(BLOCK, NAME, DOMAIN, CALLBACK, DATA) \
 465   (current_language->la_iterate_over_symbols (BLOCK, NAME, DOMAIN, CALLBACK, \
 466                                               DATA))
 467
 468 /* Test a character to decide whether it can be printed in literal form
 469    or needs to be printed in another representation.  For example,
 470    in C the literal form of the character with octal value 141 is 'a'
 471    and the "other representation" is '\141'.  The "other representation"
 472    is program language dependent.  */
 473
 474 #define PRINT_LITERAL_FORM(c)           \
 475   ((c) >= 0x20                          \
 476    && ((c) < 0x7F || (c) >= 0xA0)       \
 477    && (!sevenbit_strings || (c) < 0x80))
 478
 479 /* Type predicates */
 480
 481 extern int pointer_type (struct type *);
 482
 483 /* Checks Binary and Unary operations for semantic type correctness.  */
 484 /* FIXME:  Does not appear to be used.  */
 485 #define unop_type_check(v,o) binop_type_check((v),NULL,(o))
 486
 487 extern void binop_type_check (struct value *, struct value *, int);
 488
 489 /* Error messages */
 490
 491 extern void type_error (const char *, ...) ATTRIBUTE_PRINTF (1, 2);
 492
 493 extern void range_error (const char *, ...) ATTRIBUTE_PRINTF (1, 2);
 494
 495 /* Data:  Does this value represent "truth" to the current language?  */
 496
 497 extern int value_true (struct value *);
 498
 499 /* Misc:  The string representing a particular enum language.  */
 500
 501 extern enum language language_enum (char *str);
 502
 503 extern const struct language_defn *language_def (enum language);
 504
 505 extern char *language_str (enum language);
 506
 507 /* Add a language to the set known by GDB (at initialization time).  */
 508
 509 extern void add_language (const struct language_defn *);
 510
 511 extern enum language get_frame_language (void); /* In stack.c */
 512
 513 /* Check for a language-specific trampoline.  */
 514
 515 extern CORE_ADDR skip_language_trampoline (struct frame_info *, CORE_ADDR pc);
 516
 517 /* Return demangled language symbol, or NULL.  */
 518 extern char *language_demangle (const struct language_defn *current_language,
 519                                 const char *mangled, int options);
 520
 521 /* Return class name from physname, or NULL.  */
 522 extern char *language_class_name_from_physname (const struct language_defn *,
 523                                                 const char *physname);
 524
 525 /* Splitting strings into words.  */
 526 extern char *default_word_break_characters (void);
 527
 528 /* Print the index of an array element using the C99 syntax.  */
 529 extern void default_print_array_index (struct value *index_value,
 530                                        struct ui_file *stream,
 531                                        const struct value_print_options *options);
 532
 533 /* Return non-zero if TYPE should be passed (and returned) by
 534    reference at the language level.  */
 535 int language_pass_by_reference (struct type *type);
 536
 537 /* Return zero; by default, types are passed by value at the language
 538    level.  The target ABI may pass or return some structs by reference
 539    independent of this.  */
 540 int default_pass_by_reference (struct type *type);
 541
 542 /* The default implementation of la_print_typedef.  */
 543 void default_print_typedef (struct type *type, struct symbol *new_symbol,
 544                             struct ui_file *stream);
 545
 546 void default_get_string (struct value *value, gdb_byte **buffer, int *length,
 547                          struct type **char_type, const char **charset);
 548
 549 void c_get_string (struct value *value, gdb_byte **buffer, int *length,
 550                    struct type **char_type, const char **charset);
 551
 552 #endif /* defined (LANGUAGE_H) */