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 struct lang_varobj_ops;
  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     const char *la_name;
 136
 137     /* Natural or official name of the language.  */
 138
 139     const char *la_natural_name;
 140
 141     /* its symtab language-enum (defs.h).  */
 142
 143     enum language la_language;
 144
 145     /* Default range checking.  */
 146
 147     enum range_check la_range_check;
 148
 149     /* Default case sensitivity.  */
 150     enum case_sensitivity la_case_sensitivity;
 151
 152     /* Multi-dimensional array ordering.  */
 153     enum array_ordering la_array_ordering;
 154
 155     /* Style of macro expansion, if any, supported by this language.  */
 156     enum macro_expansion la_macro_expansion;
 157
 158     /* Definitions related to expression printing, prefixifying, and
 159        dumping.  */
 160
 161     const struct exp_descriptor *la_exp_desc;
 162
 163     /* Parser function.  */
 164
 165     int (*la_parser) (void);
 166
 167     /* Parser error function.  */
 168
 169     void (*la_error) (char *);
 170
 171     /* Given an expression *EXPP created by prefixifying the result of
 172        la_parser, perform any remaining processing necessary to complete
 173        its translation.  *EXPP may change; la_post_parser is responsible
 174        for releasing its previous contents, if necessary.  If
 175        VOID_CONTEXT_P, then no value is expected from the expression.  */
 176
 177     void (*la_post_parser) (struct expression ** expp, int void_context_p);
 178
 179     void (*la_printchar) (int ch, struct type *chtype,
 180                           struct ui_file * stream);
 181
 182     void (*la_printstr) (struct ui_file * stream, struct type *elttype,
 183                          const gdb_byte *string, unsigned int length,
 184                          const char *encoding, int force_ellipses,
 185                          const struct value_print_options *);
 186
 187     void (*la_emitchar) (int ch, struct type *chtype,
 188                          struct ui_file * stream, int quoter);
 189
 190     /* Print a type using syntax appropriate for this language.  */
 191
 192     void (*la_print_type) (struct type *, const char *, struct ui_file *, int,
 193                            int, const struct type_print_options *);
 194
 195     /* Print a typedef using syntax appropriate for this language.
 196        TYPE is the underlying type.  NEW_SYMBOL is the symbol naming
 197        the type.  STREAM is the output stream on which to print.  */
 198
 199     void (*la_print_typedef) (struct type *type, struct symbol *new_symbol,
 200                               struct ui_file *stream);
 201
 202     /* Print a value using syntax appropriate for this language.
 203
 204        TYPE is the type of the sub-object to be printed.
 205
 206        CONTENTS holds the bits of the value.  This holds the entire
 207        enclosing object.
 208
 209        EMBEDDED_OFFSET is the offset into the outermost object of the
 210        sub-object represented by TYPE.  This is the object which this
 211        call should print.  Note that the enclosing type is not
 212        available.
 213
 214        ADDRESS is the address in the inferior of the enclosing object.
 215
 216        STREAM is the stream on which the value is to be printed.
 217
 218        RECURSE is the recursion depth.  It is zero-based.
 219
 220        OPTIONS are the formatting options to be used when
 221        printing.  */
 222
 223     void (*la_val_print) (struct type *type,
 224                           const gdb_byte *contents,
 225                           int embedded_offset, CORE_ADDR address,
 226                           struct ui_file *stream, int recurse,
 227                           const struct value *val,
 228                           const struct value_print_options *options);
 229
 230     /* Print a top-level value using syntax appropriate for this language.  */
 231
 232     void (*la_value_print) (struct value *, struct ui_file *,
 233                             const struct value_print_options *);
 234
 235     /* Given a symbol VAR, and a stack frame id FRAME, read the value
 236        of the variable an return (pointer to a) struct value containing
 237        the value.
 238
 239        Throw an error if the variable cannot be found.  */
 240
 241     struct value *(*la_read_var_value) (struct symbol *var,
 242                                         struct frame_info *frame);
 243
 244     /* PC is possibly an unknown languages trampoline.
 245        If that PC falls in a trampoline belonging to this language,
 246        return the address of the first pc in the real function, or 0
 247        if it isn't a language tramp for this language.  */
 248     CORE_ADDR (*skip_trampoline) (struct frame_info *, CORE_ADDR);
 249
 250     /* Now come some hooks for lookup_symbol.  */
 251
 252     /* If this is non-NULL, specifies the name that of the implicit
 253        local variable that refers to the current object instance.  */
 254
 255     char *la_name_of_this;
 256
 257     /* This is a function that lookup_symbol will call when it gets to
 258        the part of symbol lookup where C looks up static and global
 259        variables.  */
 260
 261     struct symbol *(*la_lookup_symbol_nonlocal) (const char *,
 262                                                  const struct block *,
 263                                                  const domain_enum);
 264
 265     /* Find the definition of the type with the given name.  */
 266     struct type *(*la_lookup_transparent_type) (const char *);
 267
 268     /* Return demangled language symbol, or NULL.  */
 269     char *(*la_demangle) (const char *mangled, int options);
 270
 271     /* Return class name of a mangled method name or NULL.  */
 272     char *(*la_class_name_from_physname) (const char *physname);
 273
 274     /* Table for printing expressions.  */
 275
 276     const struct op_print *la_op_print_tab;
 277
 278     /* Zero if the language has first-class arrays.  True if there are no
 279        array values, and array objects decay to pointers, as in C.  */
 280
 281     char c_style_arrays;
 282
 283     /* Index to use for extracting the first element of a string.  */
 284     char string_lower_bound;
 285
 286     /* The list of characters forming word boundaries.  */
 287     char *(*la_word_break_characters) (void);
 288
 289     /* Should return a vector of all symbols which are possible
 290        completions for TEXT.  WORD is the entire command on which the
 291        completion is being made.  If CODE is TYPE_CODE_UNDEF, then all
 292        symbols should be examined; otherwise, only STRUCT_DOMAIN
 293        symbols whose type has a code of CODE should be matched.  */
 294     VEC (char_ptr) *(*la_make_symbol_completion_list) (const char *text,
 295                                                        const char *word,
 296                                                        enum type_code code);
 297
 298     /* The per-architecture (OS/ABI) language information.  */
 299     void (*la_language_arch_info) (struct gdbarch *,
 300                                    struct language_arch_info *);
 301
 302     /* Print the index of an element of an array.  */
 303     void (*la_print_array_index) (struct value *index_value,
 304                                   struct ui_file *stream,
 305                                   const struct value_print_options *options);
 306
 307     /* Return non-zero if TYPE should be passed (and returned) by
 308        reference at the language level.  */
 309     int (*la_pass_by_reference) (struct type *type);
 310
 311     /* Obtain a string from the inferior, storing it in a newly allocated
 312        buffer in BUFFER, which should be freed by the caller.  If the
 313        in- and out-parameter *LENGTH is specified at -1, the string is
 314        read until a null character of the appropriate width is found -
 315        otherwise the string is read to the length of characters specified.
 316        On completion, *LENGTH will hold the size of the string in characters.
 317        If a *LENGTH of -1 was specified it will count only actual
 318        characters, excluding any eventual terminating null character.
 319        Otherwise *LENGTH will include all characters - including any nulls.
 320        CHARSET will hold the encoding used in the string.  */
 321     void (*la_get_string) (struct value *value, gdb_byte **buffer, int *length,
 322                            struct type **chartype, const char **charset);
 323
 324     /* Return a pointer to the function that should be used to match
 325        a symbol name against LOOKUP_NAME. This is mostly for languages
 326        such as Ada where the matching algorithm depends on LOOKUP_NAME.
 327
 328        This field may be NULL, in which case strcmp_iw will be used
 329        to perform the matching.  */
 330     symbol_name_cmp_ftype (*la_get_symbol_name_cmp) (const char *lookup_name);
 331
 332     /* Find all symbols in the current program space matching NAME in
 333        DOMAIN, according to this language's rules.
 334
 335        The search is done in BLOCK only.
 336        The caller is responsible for iterating up through superblocks
 337        if desired.
 338
 339        For each one, call CALLBACK with the symbol and the DATA
 340        argument.  If CALLBACK returns zero, the iteration ends at that
 341        point.
 342
 343        This field may not be NULL.  If the language does not need any
 344        special processing here, 'iterate_over_symbols' should be
 345        used as the definition.  */
 346     void (*la_iterate_over_symbols) (const struct block *block,
 347                                      const char *name,
 348                                      domain_enum domain,
 349                                      symbol_found_callback_ftype *callback,
 350                                      void *data);
 351
 352     /* Various operations on varobj.  */
 353     const struct lang_varobj_ops *la_varobj_ops;
 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 range check values against the domain of their type?  */
 413 #define RANGE_CHECK (range_check != range_check_off)
 414
 415 /* "cast" really means conversion.  */
 416 /* FIXME -- should be a setting in language_defn.  */
 417 #define CAST_IS_CONVERSION(LANG) ((LANG)->la_language == language_c  || \
 418                                   (LANG)->la_language == language_cplus || \
 419                                   (LANG)->la_language == language_objc)
 420
 421 extern void language_info (int);
 422
 423 extern enum language set_language (enum language);
 424 \f
 425
 426 /* This page contains functions that return things that are
 427    specific to languages.  Each of these functions is based on
 428    the current setting of working_lang, which the user sets
 429    with the "set language" command.  */
 430
 431 #define LA_PRINT_TYPE(type,varstring,stream,show,level,flags)           \
 432   (current_language->la_print_type(type,varstring,stream,show,level,flags))
 433
 434 #define LA_PRINT_TYPEDEF(type,new_symbol,stream) \
 435   (current_language->la_print_typedef(type,new_symbol,stream))
 436
 437 #define LA_VAL_PRINT(type,valaddr,offset,addr,stream,val,recurse,options) \
 438   (current_language->la_val_print(type,valaddr,offset,addr,stream, \
 439                                   val,recurse,options))
 440 #define LA_VALUE_PRINT(val,stream,options) \
 441   (current_language->la_value_print(val,stream,options))
 442
 443 #define LA_PRINT_CHAR(ch, type, stream) \
 444   (current_language->la_printchar(ch, type, stream))
 445 #define LA_PRINT_STRING(stream, elttype, string, length, encoding, force_ellipses, options) \
 446   (current_language->la_printstr(stream, elttype, string, length, \
 447                                  encoding, force_ellipses,options))
 448 #define LA_EMIT_CHAR(ch, type, stream, quoter) \
 449   (current_language->la_emitchar(ch, type, stream, quoter))
 450 #define LA_GET_STRING(value, buffer, length, chartype, encoding) \
 451   (current_language->la_get_string(value, buffer, length, chartype, encoding))
 452
 453 #define LA_PRINT_ARRAY_INDEX(index_value, stream, options) \
 454   (current_language->la_print_array_index(index_value, stream, options))
 455
 456 #define LA_ITERATE_OVER_SYMBOLS(BLOCK, NAME, DOMAIN, CALLBACK, DATA) \
 457   (current_language->la_iterate_over_symbols (BLOCK, NAME, DOMAIN, CALLBACK, \
 458                                               DATA))
 459
 460 /* Test a character to decide whether it can be printed in literal form
 461    or needs to be printed in another representation.  For example,
 462    in C the literal form of the character with octal value 141 is 'a'
 463    and the "other representation" is '\141'.  The "other representation"
 464    is program language dependent.  */
 465
 466 #define PRINT_LITERAL_FORM(c)           \
 467   ((c) >= 0x20                          \
 468    && ((c) < 0x7F || (c) >= 0xA0)       \
 469    && (!sevenbit_strings || (c) < 0x80))
 470
 471 /* Type predicates */
 472
 473 extern int pointer_type (struct type *);
 474
 475 /* Checks Binary and Unary operations for semantic type correctness.  */
 476 /* FIXME:  Does not appear to be used.  */
 477 #define unop_type_check(v,o) binop_type_check((v),NULL,(o))
 478
 479 extern void binop_type_check (struct value *, struct value *, int);
 480
 481 /* Error messages */
 482
 483 extern void range_error (const char *, ...) ATTRIBUTE_PRINTF (1, 2);
 484
 485 /* Data:  Does this value represent "truth" to the current language?  */
 486
 487 extern int value_true (struct value *);
 488
 489 /* Misc:  The string representing a particular enum language.  */
 490
 491 extern enum language language_enum (char *str);
 492
 493 extern const struct language_defn *language_def (enum language);
 494
 495 extern const char *language_str (enum language);
 496
 497 /* Add a language to the set known by GDB (at initialization time).  */
 498
 499 extern void add_language (const struct language_defn *);
 500
 501 extern enum language get_frame_language (void); /* In stack.c */
 502
 503 /* Check for a language-specific trampoline.  */
 504
 505 extern CORE_ADDR skip_language_trampoline (struct frame_info *, CORE_ADDR pc);
 506
 507 /* Return demangled language symbol, or NULL.  */
 508 extern char *language_demangle (const struct language_defn *current_language,
 509                                 const char *mangled, int options);
 510
 511 /* Return class name from physname, or NULL.  */
 512 extern char *language_class_name_from_physname (const struct language_defn *,
 513                                                 const char *physname);
 514
 515 /* Splitting strings into words.  */
 516 extern char *default_word_break_characters (void);
 517
 518 /* Print the index of an array element using the C99 syntax.  */
 519 extern void default_print_array_index (struct value *index_value,
 520                                        struct ui_file *stream,
 521                                        const struct value_print_options *options);
 522
 523 /* Return non-zero if TYPE should be passed (and returned) by
 524    reference at the language level.  */
 525 int language_pass_by_reference (struct type *type);
 526
 527 /* Return zero; by default, types are passed by value at the language
 528    level.  The target ABI may pass or return some structs by reference
 529    independent of this.  */
 530 int default_pass_by_reference (struct type *type);
 531
 532 /* The default implementation of la_print_typedef.  */
 533 void default_print_typedef (struct type *type, struct symbol *new_symbol,
 534                             struct ui_file *stream);
 535
 536 void default_get_string (struct value *value, gdb_byte **buffer, int *length,
 537                          struct type **char_type, const char **charset);
 538
 539 void c_get_string (struct value *value, gdb_byte **buffer, int *length,
 540                    struct type **char_type, const char **charset);
 541
 542 #endif /* defined (LANGUAGE_H) */