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