gdb/language.h

   1 /* Source-language-related definitions for GDB.
   2
   3    Copyright (C) 1991, 1992, 1993, 1994, 1995, 1998, 1999, 2000, 2003, 2004,
   4    2007, 2008, 2009, 2010, 2011 Free 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 /* Structure tying together assorted information about a language.  */
 140
 141 struct language_defn
 142   {
 143     /* Name of the language.  */
 144
 145     char *la_name;
 146
 147     /* its symtab language-enum (defs.h).  */
 148
 149     enum language la_language;
 150
 151     /* Default range checking.  */
 152
 153     enum range_check la_range_check;
 154
 155     /* Default type checking.  */
 156
 157     enum type_check la_type_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     /* Definitions related to expression printing, prefixifying, and
 169        dumping.  */
 170
 171     const struct exp_descriptor *la_exp_desc;
 172
 173     /* Parser function.  */
 174
 175     int (*la_parser) (void);
 176
 177     /* Parser error function.  */
 178
 179     void (*la_error) (char *);
 180
 181     /* Given an expression *EXPP created by prefixifying the result of
 182        la_parser, perform any remaining processing necessary to complete
 183        its translation.  *EXPP may change; la_post_parser is responsible
 184        for releasing its previous contents, if necessary.  If
 185        VOID_CONTEXT_P, then no value is expected from the expression.  */
 186
 187     void (*la_post_parser) (struct expression ** expp, int void_context_p);
 188
 189     void (*la_printchar) (int ch, struct type *chtype,
 190                           struct ui_file * stream);
 191
 192     void (*la_printstr) (struct ui_file * stream, struct type *elttype,
 193                          const gdb_byte *string, unsigned int length,
 194                          const char *encoding, int force_ellipses,
 195                          const struct value_print_options *);
 196
 197     void (*la_emitchar) (int ch, struct type *chtype,
 198                          struct ui_file * stream, int quoter);
 199
 200     /* Print a type using syntax appropriate for this language.  */
 201
 202     void (*la_print_type) (struct type *, const char *, struct ui_file *, int,
 203                            int);
 204
 205     /* Print a typedef using syntax appropriate for this language.
 206        TYPE is the underlying type.  NEW_SYMBOL is the symbol naming
 207        the type.  STREAM is the output stream on which to print.  */
 208
 209     void (*la_print_typedef) (struct type *type, struct symbol *new_symbol,
 210                               struct ui_file *stream);
 211
 212     /* Print a value using syntax appropriate for this language.
 213
 214        TYPE is the type of the sub-object to be printed.
 215
 216        CONTENTS holds the bits of the value.  This holds the entire
 217        enclosing object.
 218
 219        EMBEDDED_OFFSET is the offset into the outermost object of the
 220        sub-object represented by TYPE.  This is the object which this
 221        call should print.  Note that the enclosing type is not
 222        available.
 223
 224        ADDRESS is the address in the inferior of the enclosing object.
 225
 226        STREAM is the stream on which the value is to be printed.
 227
 228        RECURSE is the recursion depth.  It is zero-based.
 229
 230        OPTIONS are the formatting options to be used when
 231        printing.  */
 232
 233     int (*la_val_print) (struct type *type,
 234                          const gdb_byte *contents,
 235                          int embedded_offset, CORE_ADDR address,
 236                          struct ui_file *stream, int recurse,
 237                          const struct value *val,
 238                          const struct value_print_options *options);
 239
 240     /* Print a top-level value using syntax appropriate for this language.  */
 241
 242     int (*la_value_print) (struct value *, struct ui_file *,
 243                            const struct value_print_options *);
 244
 245     /* PC is possibly an unknown languages trampoline.
 246        If that PC falls in a trampoline belonging to this language,
 247        return the address of the first pc in the real function, or 0
 248        if it isn't a language tramp for this language.  */
 249     CORE_ADDR (*skip_trampoline) (struct frame_info *, CORE_ADDR);
 250
 251     /* Now come some hooks for lookup_symbol.  */
 252
 253     /* If this is non-NULL, specifies the name that of the implicit
 254        local variable that refers to the current object instance.  */
 255
 256     char *la_name_of_this;
 257
 258     /* This is a function that lookup_symbol will call when it gets to
 259        the part of symbol lookup where C looks up static and global
 260        variables.  */
 261
 262     struct symbol *(*la_lookup_symbol_nonlocal) (const char *,
 263                                                  const struct block *,
 264                                                  const domain_enum);
 265
 266     /* Find the definition of the type with the given name.  */
 267     struct type *(*la_lookup_transparent_type) (const char *);
 268
 269     /* Return demangled language symbol, or NULL.  */
 270     char *(*la_demangle) (const char *mangled, int options);
 271
 272     /* Return class name of a mangled method name or NULL.  */
 273     char *(*la_class_name_from_physname) (const char *physname);
 274
 275     /* Table for printing expressions.  */
 276
 277     const struct op_print *la_op_print_tab;
 278
 279     /* Zero if the language has first-class arrays.  True if there are no
 280        array values, and array objects decay to pointers, as in C.  */
 281
 282     char c_style_arrays;
 283
 284     /* Index to use for extracting the first element of a string.  */
 285     char string_lower_bound;
 286
 287     /* The list of characters forming word boundaries.  */
 288     char *(*la_word_break_characters) (void);
 289
 290     /* Should return a NULL terminated array of all symbols which
 291        are possible completions for TEXT.  WORD is the entire command
 292        on which the completion is being made.  */
 293     char **(*la_make_symbol_completion_list) (char *text, char *word);
 294
 295     /* The per-architecture (OS/ABI) language information.  */
 296     void (*la_language_arch_info) (struct gdbarch *,
 297                                    struct language_arch_info *);
 298
 299     /* Print the index of an element of an array.  */
 300     void (*la_print_array_index) (struct value *index_value,
 301                                   struct ui_file *stream,
 302                                   const struct value_print_options *options);
 303
 304     /* Return non-zero if TYPE should be passed (and returned) by
 305        reference at the language level.  */
 306     int (*la_pass_by_reference) (struct type *type);
 307
 308     /* Obtain a string from the inferior, storing it in a newly allocated
 309        buffer in BUFFER, which should be freed by the caller.  If the
 310        in- and out-parameter *LENGTH is specified at -1, the string is
 311        read until a null character of the appropriate width is found -
 312        otherwise the string is read to the length of characters specified.
 313        On completion, *LENGTH will hold the size of the string in characters.
 314        If a *LENGTH of -1 was specified it will count only actual
 315        characters, excluding any eventual terminating null character.
 316        Otherwise *LENGTH will include all characters - including any nulls.
 317        CHARSET will hold the encoding used in the string.  */
 318     void (*la_get_string) (struct value *value, gdb_byte **buffer, int *length,
 319                            struct type **chartype, const char **charset);
 320
 321     /* Compare two symbol names according to language rules.  For
 322        instance, in C++, we might want to ignore whitespaces in
 323        the symbol name.  Or some case-insensitive language might
 324        want to ignore casing during the match.
 325
 326        Both STR1 and STR2 are expected to be demangled name, except
 327        for Ada, where STR1 and STR2 are expected to be encoded names.
 328        The latter is because searches are performed using the encoded
 329        name in Ada.
 330
 331        The return value follows the same spirit as strcmp.  */
 332
 333     int (*la_symbol_name_compare) (const char *str1, const char *str2);
 334
 335     /* Find all symbols in the current program space matching NAME in
 336        DOMAIN, according to this language's rules.
 337
 338        The search starts with BLOCK.  This function iterates upward
 339        through blocks.  When the outermost block has been finished,
 340        the function returns.
 341
 342        For each one, call CALLBACK with the symbol and the DATA
 343        argument.  If CALLBACK returns zero, the iteration ends at that
 344        point.
 345
 346        This field can be NULL, meaning that this language doesn't need
 347        any special code aside from ordinary searches of the symbol
 348        table.  */
 349     void (*la_iterate_over_symbols) (const struct block *block,
 350                                      const char *name,
 351                                      domain_enum domain,
 352                                      int (*callback) (struct symbol *, void *),
 353                                      void *data);
 354
 355     /* Add fields above this point, so the magic number is always last.  */
 356     /* Magic number for compat checking.  */
 357
 358     long la_magic;
 359
 360   };
 361
 362 #define LANG_MAGIC      910823L
 363
 364 /* Pointer to the language_defn for our current language.  This pointer
 365    always points to *some* valid struct; it can be used without checking
 366    it for validity.
 367
 368    The current language affects expression parsing and evaluation
 369    (FIXME: it might be cleaner to make the evaluation-related stuff
 370    separate exp_opcodes for each different set of semantics.  We
 371    should at least think this through more clearly with respect to
 372    what happens if the language is changed between parsing and
 373    evaluation) and printing of things like types and arrays.  It does
 374    *not* affect symbol-reading-- each source file in a symbol-file has
 375    its own language and we should keep track of that regardless of the
 376    language when symbols are read.  If we want some manual setting for
 377    the language of symbol files (e.g. detecting when ".c" files are
 378    C++), it should be a separate setting from the current_language.  */
 379
 380 extern const struct language_defn *current_language;
 381
 382 /* Pointer to the language_defn expected by the user, e.g. the language
 383    of main(), or the language we last mentioned in a message, or C.  */
 384
 385 extern const struct language_defn *expected_language;
 386
 387 /* language_mode ==
 388    language_mode_auto:   current_language automatically set upon selection
 389    of scope (e.g. stack frame)
 390    language_mode_manual: current_language set only by user.  */
 391
 392 extern enum language_mode
 393   {
 394     language_mode_auto, language_mode_manual
 395   }
 396 language_mode;
 397
 398 struct type *language_bool_type (const struct language_defn *l,
 399                                  struct gdbarch *gdbarch);
 400
 401 struct type *language_string_char_type (const struct language_defn *l,
 402                                         struct gdbarch *gdbarch);
 403
 404 struct type *language_lookup_primitive_type_by_name (const struct language_defn *l,
 405                                                      struct gdbarch *gdbarch,
 406                                                      const char *name);
 407
 408 \f
 409 /* These macros define the behaviour of the expression
 410    evaluator.  */
 411
 412 /* Should we strictly type check expressions?  */
 413 #define STRICT_TYPE (type_check != type_check_off)
 414
 415 /* Should we range check values against the domain of their type?  */
 416 #define RANGE_CHECK (range_check != range_check_off)
 417
 418 /* "cast" really means conversion.  */
 419 /* FIXME -- should be a setting in language_defn.  */
 420 #define CAST_IS_CONVERSION(LANG) ((LANG)->la_language == language_c  || \
 421                                   (LANG)->la_language == language_cplus || \
 422                                   (LANG)->la_language == language_objc)
 423
 424 extern void language_info (int);
 425
 426 extern enum language set_language (enum language);
 427 \f
 428
 429 /* This page contains functions that return things that are
 430    specific to languages.  Each of these functions is based on
 431    the current setting of working_lang, which the user sets
 432    with the "set language" command.  */
 433
 434 #define LA_PRINT_TYPE(type,varstring,stream,show,level) \
 435   (current_language->la_print_type(type,varstring,stream,show,level))
 436
 437 #define LA_PRINT_TYPEDEF(type,new_symbol,stream) \
 438   (current_language->la_print_typedef(type,new_symbol,stream))
 439
 440 #define LA_VAL_PRINT(type,valaddr,offset,addr,stream,val,recurse,options) \
 441   (current_language->la_val_print(type,valaddr,offset,addr,stream, \
 442                                   val,recurse,options))
 443 #define LA_VALUE_PRINT(val,stream,options) \
 444   (current_language->la_value_print(val,stream,options))
 445
 446 #define LA_PRINT_CHAR(ch, type, stream) \
 447   (current_language->la_printchar(ch, type, stream))
 448 #define LA_PRINT_STRING(stream, elttype, string, length, encoding, force_ellipses, options) \
 449   (current_language->la_printstr(stream, elttype, string, length, \
 450                                  encoding, force_ellipses,options))
 451 #define LA_EMIT_CHAR(ch, type, stream, quoter) \
 452   (current_language->la_emitchar(ch, type, stream, quoter))
 453 #define LA_GET_STRING(value, buffer, length, chartype, encoding) \
 454   (current_language->la_get_string(value, buffer, length, chartype, encoding))
 455
 456 #define LA_PRINT_ARRAY_INDEX(index_value, stream, options) \
 457   (current_language->la_print_array_index(index_value, stream, options))
 458
 459 #define LA_ITERATE_OVER_SYMBOLS(BLOCK, NAME, DOMAIN, CALLBACK, DATA) \
 460   (current_language->la_iterate_over_symbols (BLOCK, NAME, DOMAIN, CALLBACK, \
 461                                               DATA))
 462
 463 /* Test a character to decide whether it can be printed in literal form
 464    or needs to be printed in another representation.  For example,
 465    in C the literal form of the character with octal value 141 is 'a'
 466    and the "other representation" is '\141'.  The "other representation"
 467    is program language dependent.  */
 468
 469 #define PRINT_LITERAL_FORM(c)           \
 470   ((c) >= 0x20                          \
 471    && ((c) < 0x7F || (c) >= 0xA0)       \
 472    && (!sevenbit_strings || (c) < 0x80))
 473
 474 /* Type predicates */
 475
 476 extern int simple_type (struct type *);
 477
 478 extern int ordered_type (struct type *);
 479
 480 extern int same_type (struct type *, struct type *);
 481
 482 extern int integral_type (struct type *);
 483
 484 extern int numeric_type (struct type *);
 485
 486 extern int character_type (struct type *);
 487
 488 extern int boolean_type (struct type *);
 489
 490 extern int float_type (struct type *);
 491
 492 extern int pointer_type (struct type *);
 493
 494 extern int structured_type (struct type *);
 495
 496 /* Checks Binary and Unary operations for semantic type correctness.  */
 497 /* FIXME:  Does not appear to be used.  */
 498 #define unop_type_check(v,o) binop_type_check((v),NULL,(o))
 499
 500 extern void binop_type_check (struct value *, struct value *, int);
 501
 502 /* Error messages */
 503
 504 extern void type_error (const char *, ...) ATTRIBUTE_PRINTF (1, 2);
 505
 506 extern void range_error (const char *, ...) ATTRIBUTE_PRINTF (1, 2);
 507
 508 /* Data:  Does this value represent "truth" to the current language?  */
 509
 510 extern int value_true (struct value *);
 511
 512 /* Misc:  The string representing a particular enum language.  */
 513
 514 extern enum language language_enum (char *str);
 515
 516 extern const struct language_defn *language_def (enum language);
 517
 518 extern char *language_str (enum language);
 519
 520 /* Add a language to the set known by GDB (at initialization time).  */
 521
 522 extern void add_language (const struct language_defn *);
 523
 524 extern enum language get_frame_language (void); /* In stack.c */
 525
 526 /* Check for a language-specific trampoline.  */
 527
 528 extern CORE_ADDR skip_language_trampoline (struct frame_info *, CORE_ADDR pc);
 529
 530 /* Return demangled language symbol, or NULL.  */
 531 extern char *language_demangle (const struct language_defn *current_language,
 532                                 const char *mangled, int options);
 533
 534 /* Return class name from physname, or NULL.  */
 535 extern char *language_class_name_from_physname (const struct language_defn *,
 536                                                 const char *physname);
 537
 538 /* Splitting strings into words.  */
 539 extern char *default_word_break_characters (void);
 540
 541 /* Print the index of an array element using the C99 syntax.  */
 542 extern void default_print_array_index (struct value *index_value,
 543                                        struct ui_file *stream,
 544                                        const struct value_print_options *options);
 545
 546 /* Return non-zero if TYPE should be passed (and returned) by
 547    reference at the language level.  */
 548 int language_pass_by_reference (struct type *type);
 549
 550 /* Return zero; by default, types are passed by value at the language
 551    level.  The target ABI may pass or return some structs by reference
 552    independent of this.  */
 553 int default_pass_by_reference (struct type *type);
 554
 555 /* The default implementation of la_print_typedef.  */
 556 void default_print_typedef (struct type *type, struct symbol *new_symbol,
 557                             struct ui_file *stream);
 558
 559 void default_get_string (struct value *value, gdb_byte **buffer, int *length,
 560                          struct type **char_type, const char **charset);
 561
 562 void c_get_string (struct value *value, gdb_byte **buffer, int *length,
 563                    struct type **char_type, const char **charset);
 564
 565 #endif /* defined (LANGUAGE_H) */