xref: /netbsd-src/external/gpl3/gdb.old/dist/gdb/language.h (revision bdc22b2e01993381dcefeff2bc9b56ca75a4235c)
1 /* Source-language-related definitions for GDB.
2 
3    Copyright (C) 1991-2016 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 #include "symtab.h"
27 
28 /* Forward decls for prototypes.  */
29 struct value;
30 struct objfile;
31 struct frame_info;
32 struct expression;
33 struct ui_file;
34 struct value_print_options;
35 struct type_print_options;
36 struct lang_varobj_ops;
37 struct parser_state;
38 struct compile_instance;
39 
40 #define MAX_FORTRAN_DIMS  7	/* Maximum number of F77 array dims.  */
41 
42 /* range_mode ==
43    range_mode_auto:   range_check set automatically to default of language.
44    range_mode_manual: range_check set manually by user.  */
45 
46 extern enum range_mode
47   {
48     range_mode_auto, range_mode_manual
49   }
50 range_mode;
51 
52 /* range_check ==
53    range_check_on:    Ranges are checked in GDB expressions, producing errors.
54    range_check_warn:  Ranges are checked, producing warnings.
55    range_check_off:   Ranges are not checked in GDB expressions.  */
56 
57 extern enum range_check
58   {
59     range_check_off, range_check_warn, range_check_on
60   }
61 range_check;
62 
63 /* case_mode ==
64    case_mode_auto:   case_sensitivity set upon selection of scope.
65    case_mode_manual: case_sensitivity set only by user.  */
66 
67 extern enum case_mode
68   {
69     case_mode_auto, case_mode_manual
70   }
71 case_mode;
72 
73 /* array_ordering ==
74    array_row_major:     Arrays are in row major order.
75    array_column_major:  Arrays are in column major order.  */
76 
77 extern enum array_ordering
78   {
79     array_row_major, array_column_major
80   }
81 array_ordering;
82 
83 
84 /* case_sensitivity ==
85    case_sensitive_on:   Case sensitivity in name matching is used.
86    case_sensitive_off:  Case sensitivity in name matching is not used.  */
87 
88 extern enum case_sensitivity
89   {
90     case_sensitive_on, case_sensitive_off
91   }
92 case_sensitivity;
93 
94 
95 /* macro_expansion ==
96    macro_expansion_no:  No macro expansion is available.
97    macro_expansion_c:   C-like macro expansion is available.  */
98 
99 enum macro_expansion
100   {
101     macro_expansion_no, macro_expansion_c
102   };
103 
104 
105 /* Per architecture (OS/ABI) language information.  */
106 
107 struct language_arch_info
108 {
109   /* Its primitive types.  This is a vector ended by a NULL pointer.
110      These types can be specified by name in parsing types in
111      expressions, regardless of whether the program being debugged
112      actually defines such a type.  */
113   struct type **primitive_type_vector;
114 
115   /* Symbol wrappers around primitive_type_vector, so that the symbol lookup
116      machinery can return them.  */
117   struct symbol **primitive_type_symbols;
118 
119   /* Type of elements of strings.  */
120   struct type *string_char_type;
121 
122   /* Symbol name of type to use as boolean type, if defined.  */
123   const char *bool_type_symbol;
124   /* Otherwise, this is the default boolean builtin type.  */
125   struct type *bool_type_default;
126 };
127 
128 /* A pointer to a function expected to return nonzero if
129    SYMBOL_SEARCH_NAME matches the given LOOKUP_NAME.
130 
131    SYMBOL_SEARCH_NAME should be a symbol's "search" name.
132    LOOKUP_NAME should be the name of an entity after it has been
133    transformed for lookup.  */
134 
135 typedef int (*symbol_name_cmp_ftype) (const char *symbol_search_name,
136 					  const char *lookup_name);
137 
138 /* Structure tying together assorted information about a language.  */
139 
140 struct language_defn
141   {
142     /* Name of the language.  */
143 
144     const char *la_name;
145 
146     /* Natural or official name of the language.  */
147 
148     const char *la_natural_name;
149 
150     /* its symtab language-enum (defs.h).  */
151 
152     enum language la_language;
153 
154     /* Default range checking.  */
155 
156     enum range_check la_range_check;
157 
158     /* Default case sensitivity.  */
159     enum case_sensitivity la_case_sensitivity;
160 
161     /* Multi-dimensional array ordering.  */
162     enum array_ordering la_array_ordering;
163 
164     /* Style of macro expansion, if any, supported by this language.  */
165     enum macro_expansion la_macro_expansion;
166 
167     /* A NULL-terminated array of file extensions for this language.
168        The extension must include the ".", like ".c".  If this
169        language doesn't need to provide any filename extensions, this
170        may be NULL.  */
171 
172     const char *const *la_filename_extensions;
173 
174     /* Definitions related to expression printing, prefixifying, and
175        dumping.  */
176 
177     const struct exp_descriptor *la_exp_desc;
178 
179     /* Parser function.  */
180 
181     int (*la_parser) (struct parser_state *);
182 
183     /* Parser error function.  */
184 
185     void (*la_error) (char *);
186 
187     /* Given an expression *EXPP created by prefixifying the result of
188        la_parser, perform any remaining processing necessary to complete
189        its translation.  *EXPP may change; la_post_parser is responsible
190        for releasing its previous contents, if necessary.  If
191        VOID_CONTEXT_P, then no value is expected from the expression.  */
192 
193     void (*la_post_parser) (struct expression ** expp, int void_context_p);
194 
195     void (*la_printchar) (int ch, struct type *chtype,
196 			  struct ui_file * stream);
197 
198     void (*la_printstr) (struct ui_file * stream, struct type *elttype,
199 			 const gdb_byte *string, unsigned int length,
200 			 const char *encoding, int force_ellipses,
201 			 const struct value_print_options *);
202 
203     void (*la_emitchar) (int ch, struct type *chtype,
204 			 struct ui_file * stream, int quoter);
205 
206     /* Print a type using syntax appropriate for this language.  */
207 
208     void (*la_print_type) (struct type *, const char *, struct ui_file *, int,
209 			   int, const struct type_print_options *);
210 
211     /* Print a typedef using syntax appropriate for this language.
212        TYPE is the underlying type.  NEW_SYMBOL is the symbol naming
213        the type.  STREAM is the output stream on which to print.  */
214 
215     void (*la_print_typedef) (struct type *type, struct symbol *new_symbol,
216 			      struct ui_file *stream);
217 
218     /* Print a value using syntax appropriate for this language.
219 
220        TYPE is the type of the sub-object to be printed.
221 
222        CONTENTS holds the bits of the value.  This holds the entire
223        enclosing object.
224 
225        EMBEDDED_OFFSET is the offset into the outermost object of the
226        sub-object represented by TYPE.  This is the object which this
227        call should print.  Note that the enclosing type is not
228        available.
229 
230        ADDRESS is the address in the inferior of the enclosing object.
231 
232        STREAM is the stream on which the value is to be printed.
233 
234        RECURSE is the recursion depth.  It is zero-based.
235 
236        OPTIONS are the formatting options to be used when
237        printing.  */
238 
239     void (*la_val_print) (struct type *type,
240 			  const gdb_byte *contents,
241 			  int embedded_offset, CORE_ADDR address,
242 			  struct ui_file *stream, int recurse,
243 			  const struct value *val,
244 			  const struct value_print_options *options);
245 
246     /* Print a top-level value using syntax appropriate for this language.  */
247 
248     void (*la_value_print) (struct value *, struct ui_file *,
249 			    const struct value_print_options *);
250 
251     /* Given a symbol VAR, the corresponding block VAR_BLOCK (if any) and a
252        stack frame id FRAME, read the value of the variable and return (pointer
253        to a) struct value containing the value.
254 
255        VAR_BLOCK is needed if there's a possibility for VAR to be outside
256        FRAME.  This is what happens if FRAME correspond to a nested function
257        and VAR is defined in the outer function.  If callers know that VAR is
258        located in FRAME or is global/static, NULL can be passed as VAR_BLOCK.
259 
260        Throw an error if the variable cannot be found.  */
261 
262     struct value *(*la_read_var_value) (struct symbol *var,
263 					const struct block *var_block,
264 					struct frame_info *frame);
265 
266     /* PC is possibly an unknown languages trampoline.
267        If that PC falls in a trampoline belonging to this language,
268        return the address of the first pc in the real function, or 0
269        if it isn't a language tramp for this language.  */
270     CORE_ADDR (*skip_trampoline) (struct frame_info *, CORE_ADDR);
271 
272     /* Now come some hooks for lookup_symbol.  */
273 
274     /* If this is non-NULL, specifies the name that of the implicit
275        local variable that refers to the current object instance.  */
276 
277     char *la_name_of_this;
278 
279     /* This is a function that lookup_symbol will call when it gets to
280        the part of symbol lookup where C looks up static and global
281        variables.  */
282 
283     struct block_symbol (*la_lookup_symbol_nonlocal)
284       (const struct language_defn *,
285        const char *,
286        const struct block *,
287        const domain_enum);
288 
289     /* Find the definition of the type with the given name.  */
290     struct type *(*la_lookup_transparent_type) (const char *);
291 
292     /* Return demangled language symbol, or NULL.  */
293     char *(*la_demangle) (const char *mangled, int options);
294 
295     /* Demangle a symbol according to this language's rules.  Unlike
296        la_demangle, this does not take any options.
297 
298        *DEMANGLED will be set by this function.
299 
300        If this function returns 0, then *DEMANGLED must always be set
301        to NULL.
302 
303        If this function returns 1, the implementation may set this to
304        a xmalloc'd string holding the demangled form.  However, it is
305        not required to.  The string, if any, is owned by the caller.
306 
307        The resulting string should be of the form that will be
308        installed into a symbol.  */
309     int (*la_sniff_from_mangled_name) (const char *mangled, char **demangled);
310 
311     /* Return class name of a mangled method name or NULL.  */
312     char *(*la_class_name_from_physname) (const char *physname);
313 
314     /* Table for printing expressions.  */
315 
316     const struct op_print *la_op_print_tab;
317 
318     /* Zero if the language has first-class arrays.  True if there are no
319        array values, and array objects decay to pointers, as in C.  */
320 
321     char c_style_arrays;
322 
323     /* Index to use for extracting the first element of a string.  */
324     char string_lower_bound;
325 
326     /* The list of characters forming word boundaries.  */
327     char *(*la_word_break_characters) (void);
328 
329     /* Should return a vector of all symbols which are possible
330        completions for TEXT.  WORD is the entire command on which the
331        completion is being made.  If CODE is TYPE_CODE_UNDEF, then all
332        symbols should be examined; otherwise, only STRUCT_DOMAIN
333        symbols whose type has a code of CODE should be matched.  */
334     VEC (char_ptr) *(*la_make_symbol_completion_list) (const char *text,
335 						       const char *word,
336 						       enum type_code code);
337 
338     /* The per-architecture (OS/ABI) language information.  */
339     void (*la_language_arch_info) (struct gdbarch *,
340 				   struct language_arch_info *);
341 
342     /* Print the index of an element of an array.  */
343     void (*la_print_array_index) (struct value *index_value,
344                                   struct ui_file *stream,
345                                   const struct value_print_options *options);
346 
347     /* Return non-zero if TYPE should be passed (and returned) by
348        reference at the language level.  */
349     int (*la_pass_by_reference) (struct type *type);
350 
351     /* Obtain a string from the inferior, storing it in a newly allocated
352        buffer in BUFFER, which should be freed by the caller.  If the
353        in- and out-parameter *LENGTH is specified at -1, the string is
354        read until a null character of the appropriate width is found -
355        otherwise the string is read to the length of characters specified.
356        On completion, *LENGTH will hold the size of the string in characters.
357        If a *LENGTH of -1 was specified it will count only actual
358        characters, excluding any eventual terminating null character.
359        Otherwise *LENGTH will include all characters - including any nulls.
360        CHARSET will hold the encoding used in the string.  */
361     void (*la_get_string) (struct value *value, gdb_byte **buffer, int *length,
362 			   struct type **chartype, const char **charset);
363 
364     /* Return a pointer to the function that should be used to match
365        a symbol name against LOOKUP_NAME. This is mostly for languages
366        such as Ada where the matching algorithm depends on LOOKUP_NAME.
367 
368        This field may be NULL, in which case strcmp_iw will be used
369        to perform the matching.  */
370     symbol_name_cmp_ftype (*la_get_symbol_name_cmp) (const char *lookup_name);
371 
372     /* Find all symbols in the current program space matching NAME in
373        DOMAIN, according to this language's rules.
374 
375        The search is done in BLOCK only.
376        The caller is responsible for iterating up through superblocks
377        if desired.
378 
379        For each one, call CALLBACK with the symbol and the DATA
380        argument.  If CALLBACK returns zero, the iteration ends at that
381        point.
382 
383        This field may not be NULL.  If the language does not need any
384        special processing here, 'iterate_over_symbols' should be
385        used as the definition.  */
386     void (*la_iterate_over_symbols) (const struct block *block,
387 				     const char *name,
388 				     domain_enum domain,
389 				     symbol_found_callback_ftype *callback,
390 				     void *data);
391 
392     /* Various operations on varobj.  */
393     const struct lang_varobj_ops *la_varobj_ops;
394 
395     /* If this language allows compilation from the gdb command line,
396        this method should be non-NULL.  When called it should return
397        an instance of struct gcc_context appropriate to the language.
398        When defined this method must never return NULL; instead it
399        should throw an exception on failure.  The returned compiler
400        instance is owned by its caller and must be deallocated by
401        calling its 'destroy' method.  */
402 
403     struct compile_instance *(*la_get_compile_instance) (void);
404 
405     /* This method must be defined if 'la_get_gcc_context' is defined.
406        If 'la_get_gcc_context' is not defined, then this method is
407        ignored.
408 
409        This takes the user-supplied text and returns a newly malloc'd
410        bit of code to compile.  The caller owns the result.
411 
412        INST is the compiler instance being used.
413        INPUT is the user's input text.
414        GDBARCH is the architecture to use.
415        EXPR_BLOCK is the block in which the expression is being
416        parsed.
417        EXPR_PC is the PC at which the expression is being parsed.  */
418 
419     char *(*la_compute_program) (struct compile_instance *inst,
420 				 const char *input,
421 				 struct gdbarch *gdbarch,
422 				 const struct block *expr_block,
423 				 CORE_ADDR expr_pc);
424 
425     /* Add fields above this point, so the magic number is always last.  */
426     /* Magic number for compat checking.  */
427 
428     long la_magic;
429 
430   };
431 
432 #define LANG_MAGIC	910823L
433 
434 /* Pointer to the language_defn for our current language.  This pointer
435    always points to *some* valid struct; it can be used without checking
436    it for validity.
437 
438    The current language affects expression parsing and evaluation
439    (FIXME: it might be cleaner to make the evaluation-related stuff
440    separate exp_opcodes for each different set of semantics.  We
441    should at least think this through more clearly with respect to
442    what happens if the language is changed between parsing and
443    evaluation) and printing of things like types and arrays.  It does
444    *not* affect symbol-reading-- each source file in a symbol-file has
445    its own language and we should keep track of that regardless of the
446    language when symbols are read.  If we want some manual setting for
447    the language of symbol files (e.g. detecting when ".c" files are
448    C++), it should be a separate setting from the current_language.  */
449 
450 extern const struct language_defn *current_language;
451 
452 /* Pointer to the language_defn expected by the user, e.g. the language
453    of main(), or the language we last mentioned in a message, or C.  */
454 
455 extern const struct language_defn *expected_language;
456 
457 /* language_mode ==
458    language_mode_auto:   current_language automatically set upon selection
459    of scope (e.g. stack frame)
460    language_mode_manual: current_language set only by user.  */
461 
462 extern enum language_mode
463   {
464     language_mode_auto, language_mode_manual
465   }
466 language_mode;
467 
468 struct type *language_bool_type (const struct language_defn *l,
469 				 struct gdbarch *gdbarch);
470 
471 struct type *language_string_char_type (const struct language_defn *l,
472 					struct gdbarch *gdbarch);
473 
474 /* Look up type NAME in language L, and return its definition for architecture
475    GDBARCH.  Returns NULL if not found.  */
476 
477 struct type *language_lookup_primitive_type (const struct language_defn *l,
478 					     struct gdbarch *gdbarch,
479 					     const char *name);
480 
481 /* Wrapper around language_lookup_primitive_type to return the
482    corresponding symbol.  */
483 
484 struct symbol *
485   language_lookup_primitive_type_as_symbol (const struct language_defn *l,
486 					    struct gdbarch *gdbarch,
487 					    const char *name);
488 
489 
490 /* These macros define the behaviour of the expression
491    evaluator.  */
492 
493 /* Should we range check values against the domain of their type?  */
494 #define RANGE_CHECK (range_check != range_check_off)
495 
496 /* "cast" really means conversion.  */
497 /* FIXME -- should be a setting in language_defn.  */
498 #define CAST_IS_CONVERSION(LANG) ((LANG)->la_language == language_c  || \
499 				  (LANG)->la_language == language_cplus || \
500 				  (LANG)->la_language == language_objc)
501 
502 extern void language_info (int);
503 
504 extern enum language set_language (enum language);
505 
506 
507 /* This page contains functions that return things that are
508    specific to languages.  Each of these functions is based on
509    the current setting of working_lang, which the user sets
510    with the "set language" command.  */
511 
512 #define LA_PRINT_TYPE(type,varstring,stream,show,level,flags)		\
513   (current_language->la_print_type(type,varstring,stream,show,level,flags))
514 
515 #define LA_PRINT_TYPEDEF(type,new_symbol,stream) \
516   (current_language->la_print_typedef(type,new_symbol,stream))
517 
518 #define LA_VAL_PRINT(type,valaddr,offset,addr,stream,val,recurse,options) \
519   (current_language->la_val_print(type,valaddr,offset,addr,stream, \
520 				  val,recurse,options))
521 #define LA_VALUE_PRINT(val,stream,options) \
522   (current_language->la_value_print(val,stream,options))
523 
524 #define LA_PRINT_CHAR(ch, type, stream) \
525   (current_language->la_printchar(ch, type, stream))
526 #define LA_PRINT_STRING(stream, elttype, string, length, encoding, force_ellipses, options) \
527   (current_language->la_printstr(stream, elttype, string, length, \
528 				 encoding, force_ellipses,options))
529 #define LA_EMIT_CHAR(ch, type, stream, quoter) \
530   (current_language->la_emitchar(ch, type, stream, quoter))
531 #define LA_GET_STRING(value, buffer, length, chartype, encoding) \
532   (current_language->la_get_string(value, buffer, length, chartype, encoding))
533 
534 #define LA_PRINT_ARRAY_INDEX(index_value, stream, options) \
535   (current_language->la_print_array_index(index_value, stream, options))
536 
537 #define LA_ITERATE_OVER_SYMBOLS(BLOCK, NAME, DOMAIN, CALLBACK, DATA) \
538   (current_language->la_iterate_over_symbols (BLOCK, NAME, DOMAIN, CALLBACK, \
539 					      DATA))
540 
541 /* Test a character to decide whether it can be printed in literal form
542    or needs to be printed in another representation.  For example,
543    in C the literal form of the character with octal value 141 is 'a'
544    and the "other representation" is '\141'.  The "other representation"
545    is program language dependent.  */
546 
547 #define PRINT_LITERAL_FORM(c)		\
548   ((c) >= 0x20				\
549    && ((c) < 0x7F || (c) >= 0xA0)	\
550    && (!sevenbit_strings || (c) < 0x80))
551 
552 /* Type predicates */
553 
554 extern int pointer_type (struct type *);
555 
556 /* Error messages */
557 
558 extern void range_error (const char *, ...) ATTRIBUTE_PRINTF (1, 2);
559 
560 /* Data:  Does this value represent "truth" to the current language?  */
561 
562 extern int value_true (struct value *);
563 
564 /* Misc:  The string representing a particular enum language.  */
565 
566 extern enum language language_enum (char *str);
567 
568 extern const struct language_defn *language_def (enum language);
569 
570 extern const char *language_str (enum language);
571 
572 /* Add a language to the set known by GDB (at initialization time).  */
573 
574 extern void add_language (const struct language_defn *);
575 
576 /* Check for a language-specific trampoline.  */
577 
578 extern CORE_ADDR skip_language_trampoline (struct frame_info *, CORE_ADDR pc);
579 
580 /* Return demangled language symbol, or NULL.  */
581 extern char *language_demangle (const struct language_defn *current_language,
582 				const char *mangled, int options);
583 
584 /* A wrapper for la_sniff_from_mangled_name.  The arguments and result
585    are as for the method.  */
586 
587 extern int language_sniff_from_mangled_name (const struct language_defn *lang,
588 					     const char *mangled,
589 					     char **demangled);
590 
591 /* Return class name from physname, or NULL.  */
592 extern char *language_class_name_from_physname (const struct language_defn *,
593 					        const char *physname);
594 
595 /* Splitting strings into words.  */
596 extern char *default_word_break_characters (void);
597 
598 /* Print the index of an array element using the C99 syntax.  */
599 extern void default_print_array_index (struct value *index_value,
600                                        struct ui_file *stream,
601 				       const struct value_print_options *options);
602 
603 /* Return non-zero if TYPE should be passed (and returned) by
604    reference at the language level.  */
605 int language_pass_by_reference (struct type *type);
606 
607 /* Return zero; by default, types are passed by value at the language
608    level.  The target ABI may pass or return some structs by reference
609    independent of this.  */
610 int default_pass_by_reference (struct type *type);
611 
612 /* The default implementation of la_print_typedef.  */
613 void default_print_typedef (struct type *type, struct symbol *new_symbol,
614 			    struct ui_file *stream);
615 
616 void default_get_string (struct value *value, gdb_byte **buffer, int *length,
617 			 struct type **char_type, const char **charset);
618 
619 void c_get_string (struct value *value, gdb_byte **buffer, int *length,
620 		   struct type **char_type, const char **charset);
621 
622 #endif /* defined (LANGUAGE_H) */
623