gdb/language.h

   1 /* Source-language-related definitions for GDB.
   2
   3    Copyright (C) 1991-2013 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 /* Forward decls for prototypes.  */
  27 struct value;
  28 struct objfile;
  29 struct frame_info;
  30 struct expression;
  31 struct ui_file;
  32 struct value_print_options;
  33 struct type_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 /* case_mode ==
  59    case_mode_auto:   case_sensitivity set upon selection of scope.
  60    case_mode_manual: case_sensitivity set only by user.  */
  61
  62 extern enum case_mode
  63   {
  64     case_mode_auto, case_mode_manual
  65   }
  66 case_mode;
  67
  68 /* array_ordering ==
  69    array_row_major:     Arrays are in row major order.
  70    array_column_major:  Arrays are in column major order.  */
  71
  72 extern enum array_ordering
  73   {
  74     array_row_major, array_column_major
  75   }
  76 array_ordering;
  77
  78
  79 /* case_sensitivity ==
  80    case_sensitive_on:   Case sensitivity in name matching is used.
  81    case_sensitive_off:  Case sensitivity in name matching is not used.  */
  82
  83 extern enum case_sensitivity
  84   {
  85     case_sensitive_on, case_sensitive_off
  86   }
  87 case_sensitivity;
  88
  89
  90 /* macro_expansion ==
  91    macro_expansion_no:  No macro expansion is available.
  92    macro_expansion_c:   C-like macro expansion is available.  */
  93
  94 enum macro_expansion
  95   {
  96     macro_expansion_no, macro_expansion_c
  97   };
  98
  99 \f
 100 /* Per architecture (OS/ABI) language information.  */
 101
 102 struct language_arch_info
 103 {
 104   /* Its primitive types.  This is a vector ended by a NULL pointer.
 105      These types can be specified by name in parsing types in
 106      expressions, regardless of whether the program being debugged
 107      actually defines such a type.  */
 108   struct type **primitive_type_vector;
 109   /* Type of elements of strings.  */
 110   struct type *string_char_type;
 111
 112   /* Symbol name of type to use as boolean type, if defined.  */
 113   const char *bool_type_symbol;
 114   /* Otherwise, this is the default boolean builtin type.  */
 115   struct type *bool_type_default;
 116 };
 117
 118 /* A pointer to a function expected to return nonzero if
 119    SYMBOL_SEARCH_NAME matches the given LOOKUP_NAME.
 120
 121    SYMBOL_SEARCH_NAME should be a symbol's "search" name.
 122    LOOKUP_NAME should be the name of an entity after it has been
 123    transformed for lookup.  */
 124
 125 typedef int (*symbol_name_cmp_ftype) (const char *symbol_search_name,
 126                                           const char *lookup_name);
 127
 128 /* Structure tying together assorted information about a language.  */
 129
 130 struct language_defn
 131   {
 132     /* Name of the language.  */
 133
 134     char *la_name;
 135
 136     /* its symtab language-enum (defs.h).  */
 137
 138     enum language la_language;
 139
 140     /* Default range checking.  */
 141
 142     enum range_check la_range_check;
 143
 144     /* Default case sensitivity.  */
 145     enum case_sensitivity la_case_sensitivity;
 146
 147     /* Multi-dimensional array ordering.  */
 148     enum array_ordering la_array_ordering;
 149
 150     /* Style of macro expansion, if any, supported by this language.  */
 151     enum macro_expansion la_macro_expansion;
 152
 153     /* Definitions related to expression printing, prefixifying, and
 154        dumping.  */
 155
 156     const struct exp_descriptor *la_exp_desc;
 157
 158     /* Parser function.  */
 159
 160     int (*la_parser) (void);
 161
 162     /* Parser error function.  */
 163
 164     void (*la_error) (char *);
 165
 166     /* Given an expression *EXPP created by prefixifying the result of
 167        la_parser, perform any remaining processing necessary to complete
 168        its translation.  *EXPP may change; la_post_parser is responsible
 169        for releasing its previous contents, if necessary.  If
 170        VOID_CONTEXT_P, then no value is expected from the expression.  */
 171
 172     void (*la_post_parser) (struct expression ** expp, int void_context_p);
 173
 174     void (*la_printchar) (int ch, struct type *chtype,
 175                           struct ui_file * stream);
 176
 177     void (*la_printstr) (struct ui_file * stream, struct type *elttype,
 178                          const gdb_byte *string, unsigned int length,
 179                          const char *encoding, int force_ellipses,
 180                          const struct value_print_options *);
 181
 182     void (*la_emitchar) (int ch, struct type *chtype,
 183                          struct ui_file * stream, int quoter);
 184
 185     /* Print a type using syntax appropriate for this language.  */
 186
 187     void (*la_print_type) (struct type *, const char *, struct ui_file *, int,
 188                            int, const struct type_print_options *);
 189
 190     /* Print a typedef using syntax appropriate for this language.
 191        TYPE is the underlying type.  NEW_SYMBOL is the symbol naming
 192        the type.  STREAM is the output stream on which to print.  */
 193
 194     void (*la_print_typedef) (struct type *type, struct symbol *new_symbol,
 195                               struct ui_file *stream);
 196
 197     /* Print a value using syntax appropriate for this language.
 198
 199        TYPE is the type of the sub-object to be printed.
 200
 201        CONTENTS holds the bits of the value.  This holds the entire
 202        enclosing object.
 203
 204        EMBEDDED_OFFSET is the offset into the outermost object of the
 205        sub-object represented by TYPE.  This is the object which this
 206        call should print.  Note that the enclosing type is not
 207        available.
 208
 209        ADDRESS is the address in the inferior of the enclosing object.
 210
 211        STREAM is the stream on which the value is to be printed.
 212
 213        RECURSE is the recursion depth.  It is zero-based.
 214
 215        OPTIONS are the formatting options to be used when
 216        printing.  */
 217
 218     void (*la_val_print) (struct type *type,
 219                           const gdb_byte *contents,
 220                           int embedded_offset, CORE_ADDR address,
 221                           struct ui_file *stream, int recurse,
 222                           const struct value *val,
 223                           const struct value_print_options *options);
 224
 225     /* Print a top-level value using syntax appropriate for this language.  */
 226
 227     void (*la_value_print) (struct value *, struct ui_file *,
 228                             const struct value_print_options *);
 229
 230     /* Given a symbol VAR, and a stack frame id FRAME, read the value
 231        of the variable an return (pointer to a) struct value containing
 232        the value.
 233
 234        Throw an error if the variable cannot be found.  */
 235
 236     struct value *(*la_read_var_value) (struct symbol *var,
 237                                         struct frame_info *frame);
 238
 239     /* PC is possibly an unknown languages trampoline.
 240        If that PC falls in a trampoline belonging to this language,
 241        return the address of the first pc in the real function, or 0
 242        if it isn't a language tramp for this language.  */
 243     CORE_ADDR (*skip_trampoline) (struct frame_info *, CORE_ADDR);
 244
 245     /* Now come some hooks for lookup_symbol.  */
 246
 247     /* If this is non-NULL, specifies the name that of the implicit
 248        local variable that refers to the current object instance.  */
 249
 250     char *la_name_of_this;
 251
 252     /* This is a function that lookup_symbol will call when it gets to
 253        the part of symbol lookup where C looks up static and global
 254        variables.  */
 255
 256     struct symbol *(*la_lookup_symbol_nonlocal) (const char *,
 257                                                  const struct block *,
 258                                                  const domain_enum);
 259
 260     /* Find the definition of the type with the given name.  */
 261     struct type *(*la_lookup_transparent_type) (const char *);
 262
 263     /* Return demangled language symbol, or NULL.  */
 264     char *(*la_demangle) (const char *mangled, int options);
 265
 266     /* Return class name of a mangled method name or NULL.  */
 267     char *(*la_class_name_from_physname) (const char *physname);
 268
 269     /* Table for printing expressions.  */
 270
 271     const struct op_print *la_op_print_tab;
 272
 273     /* Zero if the language has first-class arrays.  True if there are no
 274        array values, and array objects decay to pointers, as in C.  */
 275
 276     char c_style_arrays;
 277
 278     /* Index to use for extracting the first element of a string.  */
 279     char string_lower_bound;
 280
 281     /* The list of characters forming word boundaries.  */
 282     char *(*la_word_break_characters) (void);
 283
 284     /* Should return a vector of all symbols which are possible
 285        completions for TEXT.  WORD is the entire command on which the
 286        completion is being made.  If CODE is TYPE_CODE_UNDEF, then all
 287        symbols should be examined; otherwise, only STRUCT_DOMAIN
 288        symbols whose type has a code of CODE should be matched.  */
 289     VEC (char_ptr) *(*la_make_symbol_completion_list) (const char *text,
 290                                                        const char *word,
 291                                                        enum type_code code);
 292
 293     /* The per-architecture (OS/ABI) language information.  */
 294     void (*la_language_arch_info) (struct gdbarch *,
 295                                    struct language_arch_info *);
 296
 297     /* Print the index of an element of an array.  */
 298     void (*la_print_array_index) (struct value *index_value,
 299                                   struct ui_file *stream,
 300                                   const struct value_print_options *options);
 301
 302     /* Return non-zero if TYPE should be passed (and returned) by
 303        reference at the language level.  */
 304     int (*la_pass_by_reference) (struct type *type);
 305
 306     /* Obtain a string from the inferior, storing it in a newly allocated
 307        buffer in BUFFER, which should be freed by the caller.  If the
 308        in- and out-parameter *LENGTH is specified at -1, the string is
 309        read until a null character of the appropriate width is found -
 310        otherwise the string is read to the length of characters specified.
 311        On completion, *LENGTH will hold the size of the string in characters.
 312        If a *LENGTH of -1 was specified it will count only actual
 313        characters, excluding any eventual terminating null character.
 314        Otherwise *LENGTH will include all characters - including any nulls.
 315        CHARSET will hold the encoding used in the string.  */
 316     void (*la_get_string) (struct value *value, gdb_byte **buffer, int *length,
 317                            struct type **chartype, const char **charset);
 318
 319     /* Return a pointer to the function that should be used to match
 320        a symbol name against LOOKUP_NAME. This is mostly for languages
 321        such as Ada where the matching algorithm depends on LOOKUP_NAME.
 322
 323        This field may be NULL, in which case strcmp_iw will be used
 324        to perform the matching.  */
 325     symbol_name_cmp_ftype (*la_get_symbol_name_cmp) (const char *lookup_name);
 326
 327     /* Find all symbols in the current program space matching NAME in
 328        DOMAIN, according to this language's rules.
 329
 330        The search is done in BLOCK only.
 331        The caller is responsible for iterating up through superblocks
 332        if desired.
 333
 334        For each one, call CALLBACK with the symbol and the DATA
 335        argument.  If CALLBACK returns zero, the iteration ends at that
 336        point.
 337
 338        This field may not be NULL.  If the language does not need any
 339        special processing here, 'iterate_over_symbols' should be
 340        used as the definition.  */
 341     void (*la_iterate_over_symbols) (const struct block *block,
 342                                      const char *name,
 343                                      domain_enum domain,
 344                                      symbol_found_callback_ftype *callback,
 345                                      void *data);
 346
 347     /* Add fields above this point, so the magic number is always last.  */
 348     /* Magic number for compat checking.  */
 349
 350     long la_magic;
 351
 352   };
 353
 354 #define LANG_MAGIC      910823L
 355
 356 /* Pointer to the language_defn for our current language.  This pointer
 357    always points to *some* valid struct; it can be used without checking
 358    it for validity.
 359
 360    The current language affects expression parsing and evaluation
 361    (FIXME: it might be cleaner to make the evaluation-related stuff
 362    separate exp_opcodes for each different set of semantics.  We
 363    should at least think this through more clearly with respect to
 364    what happens if the language is changed between parsing and
 365    evaluation) and printing of things like types and arrays.  It does
 366    *not* affect symbol-reading-- each source file in a symbol-file has
 367    its own language and we should keep track of that regardless of the
 368    language when symbols are read.  If we want some manual setting for
 369    the language of symbol files (e.g. detecting when ".c" files are
 370    C++), it should be a separate setting from the current_language.  */
 371
 372 extern const struct language_defn *current_language;
 373
 374 /* Pointer to the language_defn expected by the user, e.g. the language
 375    of main(), or the language we last mentioned in a message, or C.  */
 376
 377 extern const struct language_defn *expected_language;
 378
 379 /* language_mode ==
 380    language_mode_auto:   current_language automatically set upon selection
 381    of scope (e.g. stack frame)
 382    language_mode_manual: current_language set only by user.  */
 383
 384 extern enum language_mode
 385   {
 386     language_mode_auto, language_mode_manual
 387   }
 388 language_mode;
 389
 390 struct type *language_bool_type (const struct language_defn *l,
 391                                  struct gdbarch *gdbarch);
 392
 393 struct type *language_string_char_type (const struct language_defn *l,
 394                                         struct gdbarch *gdbarch);
 395
 396 struct type *language_lookup_primitive_type_by_name (const struct language_defn *l,
 397                                                      struct gdbarch *gdbarch,
 398                                                      const char *name);
 399
 400 \f
 401 /* These macros define the behaviour of the expression
 402    evaluator.  */
 403
 404 /* Should we range check values against the domain of their type?  */
 405 #define RANGE_CHECK (range_check != range_check_off)
 406
 407 /* "cast" really means conversion.  */
 408 /* FIXME -- should be a setting in language_defn.  */
 409 #define CAST_IS_CONVERSION(LANG) ((LANG)->la_language == language_c  || \
 410                                   (LANG)->la_language == language_cplus || \
 411                                   (LANG)->la_language == language_objc)
 412
 413 extern void language_info (int);
 414
 415 extern enum language set_language (enum language);
 416 \f
 417
 418 /* This page contains functions that return things that are
 419    specific to languages.  Each of these functions is based on
 420    the current setting of working_lang, which the user sets
 421    with the "set language" command.  */
 422
 423 #define LA_PRINT_TYPE(type,varstring,stream,show,level,flags)           \
 424   (current_language->la_print_type(type,varstring,stream,show,level,flags))
 425
 426 #define LA_PRINT_TYPEDEF(type,new_symbol,stream) \
 427   (current_language->la_print_typedef(type,new_symbol,stream))
 428
 429 #define LA_VAL_PRINT(type,valaddr,offset,addr,stream,val,recurse,options) \
 430   (current_language->la_val_print(type,valaddr,offset,addr,stream, \
 431                                   val,recurse,options))
 432 #define LA_VALUE_PRINT(val,stream,options) \
 433   (current_language->la_value_print(val,stream,options))
 434
 435 #define LA_PRINT_CHAR(ch, type, stream) \
 436   (current_language->la_printchar(ch, type, stream))
 437 #define LA_PRINT_STRING(stream, elttype, string, length, encoding, force_ellipses, options) \
 438   (current_language->la_printstr(stream, elttype, string, length, \
 439                                  encoding, force_ellipses,options))
 440 #define LA_EMIT_CHAR(ch, type, stream, quoter) \
 441   (current_language->la_emitchar(ch, type, stream, quoter))
 442 #define LA_GET_STRING(value, buffer, length, chartype, encoding) \
 443   (current_language->la_get_string(value, buffer, length, chartype, encoding))
 444
 445 #define LA_PRINT_ARRAY_INDEX(index_value, stream, options) \
 446   (current_language->la_print_array_index(index_value, stream, options))
 447
 448 #define LA_ITERATE_OVER_SYMBOLS(BLOCK, NAME, DOMAIN, CALLBACK, DATA) \
 449   (current_language->la_iterate_over_symbols (BLOCK, NAME, DOMAIN, CALLBACK, \
 450                                               DATA))
 451
 452 /* Test a character to decide whether it can be printed in literal form
 453    or needs to be printed in another representation.  For example,
 454    in C the literal form of the character with octal value 141 is 'a'
 455    and the "other representation" is '\141'.  The "other representation"
 456    is program language dependent.  */
 457
 458 #define PRINT_LITERAL_FORM(c)           \
 459   ((c) >= 0x20                          \
 460    && ((c) < 0x7F || (c) >= 0xA0)       \
 461    && (!sevenbit_strings || (c) < 0x80))
 462
 463 /* Type predicates */
 464
 465 extern int pointer_type (struct type *);
 466
 467 /* Checks Binary and Unary operations for semantic type correctness.  */
 468 /* FIXME:  Does not appear to be used.  */
 469 #define unop_type_check(v,o) binop_type_check((v),NULL,(o))
 470
 471 extern void binop_type_check (struct value *, struct value *, int);
 472
 473 /* Error messages */
 474
 475 extern void range_error (const char *, ...) ATTRIBUTE_PRINTF (1, 2);
 476
 477 /* Data:  Does this value represent "truth" to the current language?  */
 478
 479 extern int value_true (struct value *);
 480
 481 /* Misc:  The string representing a particular enum language.  */
 482
 483 extern enum language language_enum (char *str);
 484
 485 extern const struct language_defn *language_def (enum language);
 486
 487 extern char *language_str (enum language);
 488
 489 /* Add a language to the set known by GDB (at initialization time).  */
 490
 491 extern void add_language (const struct language_defn *);
 492
 493 extern enum language get_frame_language (void); /* In stack.c */
 494
 495 /* Check for a language-specific trampoline.  */
 496
 497 extern CORE_ADDR skip_language_trampoline (struct frame_info *, CORE_ADDR pc);
 498
 499 /* Return demangled language symbol, or NULL.  */
 500 extern char *language_demangle (const struct language_defn *current_language,
 501                                 const char *mangled, int options);
 502
 503 /* Return class name from physname, or NULL.  */
 504 extern char *language_class_name_from_physname (const struct language_defn *,
 505                                                 const char *physname);
 506
 507 /* Splitting strings into words.  */
 508 extern char *default_word_break_characters (void);
 509
 510 /* Print the index of an array element using the C99 syntax.  */
 511 extern void default_print_array_index (struct value *index_value,
 512                                        struct ui_file *stream,
 513                                        const struct value_print_options *options);
 514
 515 /* Return non-zero if TYPE should be passed (and returned) by
 516    reference at the language level.  */
 517 int language_pass_by_reference (struct type *type);
 518
 519 /* Return zero; by default, types are passed by value at the language
 520    level.  The target ABI may pass or return some structs by reference
 521    independent of this.  */
 522 int default_pass_by_reference (struct type *type);
 523
 524 /* The default implementation of la_print_typedef.  */
 525 void default_print_typedef (struct type *type, struct symbol *new_symbol,
 526                             struct ui_file *stream);
 527
 528 void default_get_string (struct value *value, gdb_byte **buffer, int *length,
 529                          struct type **char_type, const char **charset);
 530
 531 void c_get_string (struct value *value, gdb_byte **buffer, int *length,
 532                    struct type **char_type, const char **charset);
 533
 534 #endif /* defined (LANGUAGE_H) */