1 /* Helper routines for C++ support in GDB.
2 Copyright (C) 2003, 2004, 2007, 2008, 2009, 2010
3 Free Software Foundation, Inc.
5 Contributed by David Carlton and by Kealia, Inc.
7 This file is part of GDB.
9 This program is free software; you can redistribute it and/or modify
10 it under the terms of the GNU General Public License as published by
11 the Free Software Foundation; either version 3 of the License, or
12 (at your option) any later version.
14 This program is distributed in the hope that it will be useful,
15 but WITHOUT ANY WARRANTY; without even the implied warranty of
16 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
17 GNU General Public License for more details.
19 You should have received a copy of the GNU General Public License
20 along with this program. If not, see <http://www.gnu.org/licenses/>. */
23 #include "cp-support.h"
24 #include "gdb_obstack.h"
27 #include "gdb_assert.h"
31 #include "dictionary.h"
36 static struct symbol
*lookup_namespace_scope (const char *name
,
37 const char *linkage_name
,
38 const struct block
*block
,
39 const domain_enum domain
,
43 static struct symbol
*lookup_symbol_file (const char *name
,
44 const char *linkage_name
,
45 const struct block
*block
,
46 const domain_enum domain
,
47 int anonymous_namespace
);
49 static struct type
*cp_lookup_transparent_type_loop (const char *name
,
53 static void initialize_namespace_symtab (struct objfile
*objfile
);
55 static struct block
*get_possible_namespace_block (struct objfile
*objfile
);
57 static void free_namespace_block (struct symtab
*symtab
);
59 static int check_possible_namespace_symbols_loop (const char *name
,
61 struct objfile
*objfile
);
63 static int check_one_possible_namespace_symbol (const char *name
,
65 struct objfile
*objfile
);
67 static struct symbol
*lookup_possible_namespace_symbol (const char *name
);
69 static void maintenance_cplus_namespace (char *args
, int from_tty
);
71 /* Check to see if SYMBOL refers to an object contained within an
72 anonymous namespace; if so, add an appropriate using directive. */
74 /* Optimize away strlen ("(anonymous namespace)"). */
76 #define ANONYMOUS_NAMESPACE_LEN 21
79 cp_scan_for_anonymous_namespaces (const struct symbol
*symbol
)
81 if (SYMBOL_DEMANGLED_NAME (symbol
) != NULL
)
83 const char *name
= SYMBOL_DEMANGLED_NAME (symbol
);
84 unsigned int previous_component
;
85 unsigned int next_component
;
88 /* Start with a quick-and-dirty check for mention of "(anonymous
91 if (!cp_is_anonymous (name
))
94 previous_component
= 0;
95 next_component
= cp_find_first_component (name
+ previous_component
);
97 while (name
[next_component
] == ':')
99 if ((next_component
- previous_component
) == ANONYMOUS_NAMESPACE_LEN
100 && strncmp (name
+ previous_component
,
101 "(anonymous namespace)",
102 ANONYMOUS_NAMESPACE_LEN
) == 0)
104 int dest_len
= (previous_component
== 0 ? 0 : previous_component
- 2);
105 int src_len
= next_component
;
107 char *dest
= alloca (dest_len
+ 1);
108 char *src
= alloca (src_len
+ 1);
110 memcpy (dest
, name
, dest_len
);
111 memcpy (src
, name
, src_len
);
113 dest
[dest_len
] = '\0';
116 /* We've found a component of the name that's an
117 anonymous namespace. So add symbols in it to the
118 namespace given by the previous component if there is
119 one, or to the global namespace if there isn't. */
120 cp_add_using_directive (dest
, src
);
122 /* The "+ 2" is for the "::". */
123 previous_component
= next_component
+ 2;
124 next_component
= (previous_component
125 + cp_find_first_component (name
126 + previous_component
));
131 /* Add a using directive to using_list. If the using directive in question
132 has already been added, don't add it twice. */
135 cp_add_using_directive (const char *dest
, const char *src
)
137 struct using_direct
*current
;
138 struct using_direct
*new;
140 /* Has it already been added? */
142 for (current
= using_directives
; current
!= NULL
; current
= current
->next
)
144 if (strcmp (current
->import_src
, src
) == 0
145 && strcmp (current
->import_dest
, dest
) == 0)
149 using_directives
= cp_add_using (dest
, src
, using_directives
);
153 /* Record the namespace that the function defined by SYMBOL was
154 defined in, if necessary. BLOCK is the associated block; use
155 OBSTACK for allocation. */
158 cp_set_block_scope (const struct symbol
*symbol
,
160 struct obstack
*obstack
,
161 const char *processing_current_prefix
,
162 int processing_has_namespace_info
)
164 if (processing_has_namespace_info
)
167 (block
, obsavestring (processing_current_prefix
,
168 strlen (processing_current_prefix
),
172 else if (SYMBOL_DEMANGLED_NAME (symbol
) != NULL
)
174 /* Try to figure out the appropriate namespace from the
177 /* FIXME: carlton/2003-04-15: If the function in question is
178 a method of a class, the name will actually include the
179 name of the class as well. This should be harmless, but
180 is a little unfortunate. */
182 const char *name
= SYMBOL_DEMANGLED_NAME (symbol
);
183 unsigned int prefix_len
= cp_entire_prefix_len (name
);
185 block_set_scope (block
,
186 obsavestring (name
, prefix_len
, obstack
),
191 /* Test whether or not NAMESPACE looks like it mentions an anonymous
192 namespace; return nonzero if so. */
195 cp_is_anonymous (const char *namespace)
197 return (strstr (namespace, "(anonymous namespace)")
201 /* Create a new struct using direct which imports the namespace SRC
203 Set its next member in the linked list to NEXT; allocate all memory
204 using xmalloc. It copies the strings, so NAME can be a temporary
207 struct using_direct
*
208 cp_add_using (const char *dest
,
210 struct using_direct
*next
)
212 struct using_direct
*retval
;
214 retval
= xmalloc (sizeof (struct using_direct
));
215 retval
->import_src
= savestring (src
, strlen(src
));
216 retval
->import_dest
= savestring (dest
, strlen(dest
));
222 /* The C++-specific version of name lookup for static and global
223 names. This makes sure that names get looked for in all namespaces
224 that are in scope. NAME is the natural name of the symbol that
225 we're looking for, LINKAGE_NAME (which is optional) is its linkage
226 name, BLOCK is the block that we're searching within, DOMAIN says
227 what kind of symbols we're looking for, and if SYMTAB is non-NULL,
228 we should store the symtab where we found the symbol in it. */
231 cp_lookup_symbol_nonlocal (const char *name
,
232 const char *linkage_name
,
233 const struct block
*block
,
234 const domain_enum domain
)
236 return lookup_namespace_scope (name
, linkage_name
, block
, domain
,
237 block_scope (block
), 0);
240 /* Lookup NAME at namespace scope (or, in C terms, in static and
241 global variables). SCOPE is the namespace that the current
242 function is defined within; only consider namespaces whose length
243 is at least SCOPE_LEN. Other arguments are as in
244 cp_lookup_symbol_nonlocal.
246 For example, if we're within a function A::B::f and looking for a
247 symbol x, this will get called with NAME = "x", SCOPE = "A::B", and
248 SCOPE_LEN = 0. It then calls itself with NAME and SCOPE the same,
249 but with SCOPE_LEN = 1. And then it calls itself with NAME and
250 SCOPE the same, but with SCOPE_LEN = 4. This third call looks for
251 "A::B::x"; if it doesn't find it, then the second call looks for
252 "A::x", and if that call fails, then the first call looks for
255 static struct symbol
*
256 lookup_namespace_scope (const char *name
,
257 const char *linkage_name
,
258 const struct block
*block
,
259 const domain_enum domain
,
265 if (scope
[scope_len
] != '\0')
267 /* Recursively search for names in child namespaces first. */
270 int new_scope_len
= scope_len
;
272 /* If the current scope is followed by "::", skip past that. */
273 if (new_scope_len
!= 0)
275 gdb_assert (scope
[new_scope_len
] == ':');
278 new_scope_len
+= cp_find_first_component (scope
+ new_scope_len
);
279 sym
= lookup_namespace_scope (name
, linkage_name
, block
,
280 domain
, scope
, new_scope_len
);
285 /* Okay, we didn't find a match in our children, so look for the
286 name in the current namespace. */
288 namespace = alloca (scope_len
+ 1);
289 strncpy (namespace, scope
, scope_len
);
290 namespace[scope_len
] = '\0';
291 return cp_lookup_symbol_namespace (namespace, name
, linkage_name
,
295 /* Look up NAME in the C++ namespace NAMESPACE, applying the using
296 directives that are active in BLOCK. Other arguments are as in
297 cp_lookup_symbol_nonlocal. */
300 cp_lookup_symbol_namespace (const char *namespace,
302 const char *linkage_name
,
303 const struct block
*block
,
304 const domain_enum domain
)
306 const struct using_direct
*current
;
309 /* First, go through the using directives. If any of them add new
310 names to the namespace we're searching in, see if we can find a
311 match by applying them. */
313 for (current
= block_using (block
);
315 current
= current
->next
)
317 if (strcmp (namespace, current
->import_dest
) == 0)
319 sym
= cp_lookup_symbol_namespace (current
->import_src
,
329 /* We didn't find anything by applying any of the using directives
330 that are still applicable; so let's see if we've got a match
331 using the current namespace. */
333 if (namespace[0] == '\0')
335 return lookup_symbol_file (name
, linkage_name
, block
,
340 char *concatenated_name
341 = alloca (strlen (namespace) + 2 + strlen (name
) + 1);
342 strcpy (concatenated_name
, namespace);
343 strcat (concatenated_name
, "::");
344 strcat (concatenated_name
, name
);
345 sym
= lookup_symbol_file (concatenated_name
, linkage_name
,
347 cp_is_anonymous (namespace));
352 /* Look up NAME in BLOCK's static block and in global blocks. If
353 ANONYMOUS_NAMESPACE is nonzero, the symbol in question is located
354 within an anonymous namespace. Other arguments are as in
355 cp_lookup_symbol_nonlocal. */
357 static struct symbol
*
358 lookup_symbol_file (const char *name
,
359 const char *linkage_name
,
360 const struct block
*block
,
361 const domain_enum domain
,
362 int anonymous_namespace
)
364 struct symbol
*sym
= NULL
;
366 sym
= lookup_symbol_static (name
, linkage_name
, block
, domain
);
370 if (anonymous_namespace
)
372 /* Symbols defined in anonymous namespaces have external linkage
373 but should be treated as local to a single file nonetheless.
374 So we only search the current file's global block. */
376 const struct block
*global_block
= block_global_block (block
);
378 if (global_block
!= NULL
)
379 sym
= lookup_symbol_aux_block (name
, linkage_name
, global_block
,
384 sym
= lookup_symbol_global (name
, linkage_name
, block
, domain
);
390 /* Now call "lookup_possible_namespace_symbol". Symbols in here
391 claim to be associated to namespaces, but this claim might be
392 incorrect: the names in question might actually correspond to
393 classes instead of namespaces. But if they correspond to
394 classes, then we should have found a match for them above. So if
395 we find them now, they should be genuine. */
397 /* FIXME: carlton/2003-06-12: This is a hack and should eventually
398 be deleted: see comments below. */
400 if (domain
== VAR_DOMAIN
)
402 sym
= lookup_possible_namespace_symbol (name
);
410 /* Look up a type named NESTED_NAME that is nested inside the C++
411 class or namespace given by PARENT_TYPE, from within the context
412 given by BLOCK. Return NULL if there is no such nested type. */
415 cp_lookup_nested_type (struct type
*parent_type
,
416 const char *nested_name
,
417 const struct block
*block
)
419 switch (TYPE_CODE (parent_type
))
421 case TYPE_CODE_STRUCT
:
422 case TYPE_CODE_NAMESPACE
:
424 /* NOTE: carlton/2003-11-10: We don't treat C++ class members
425 of classes like, say, data or function members. Instead,
426 they're just represented by symbols whose names are
427 qualified by the name of the surrounding class. This is
428 just like members of namespaces; in particular,
429 lookup_symbol_namespace works when looking them up. */
431 const char *parent_name
= TYPE_TAG_NAME (parent_type
);
432 struct symbol
*sym
= cp_lookup_symbol_namespace (parent_name
,
437 if (sym
== NULL
|| SYMBOL_CLASS (sym
) != LOC_TYPEDEF
)
440 return SYMBOL_TYPE (sym
);
443 internal_error (__FILE__
, __LINE__
,
444 _("cp_lookup_nested_type called on a non-aggregate type."));
448 /* The C++-version of lookup_transparent_type. */
450 /* FIXME: carlton/2004-01-16: The problem that this is trying to
451 address is that, unfortunately, sometimes NAME is wrong: it may not
452 include the name of namespaces enclosing the type in question.
453 lookup_transparent_type gets called when the the type in question
454 is a declaration, and we're trying to find its definition; but, for
455 declarations, our type name deduction mechanism doesn't work.
456 There's nothing we can do to fix this in general, I think, in the
457 absence of debug information about namespaces (I've filed PR
458 gdb/1511 about this); until such debug information becomes more
459 prevalent, one heuristic which sometimes looks is to search for the
460 definition in namespaces containing the current namespace.
462 We should delete this functions once the appropriate debug
463 information becomes more widespread. (GCC 3.4 will be the first
464 released version of GCC with such information.) */
467 cp_lookup_transparent_type (const char *name
)
469 /* First, try the honest way of looking up the definition. */
470 struct type
*t
= basic_lookup_transparent_type (name
);
476 /* If that doesn't work and we're within a namespace, look there
478 scope
= block_scope (get_selected_block (0));
480 if (scope
[0] == '\0')
483 return cp_lookup_transparent_type_loop (name
, scope
, 0);
486 /* Lookup the the type definition associated to NAME in
487 namespaces/classes containing SCOPE whose name is strictly longer
488 than LENGTH. LENGTH must be the index of the start of a
489 component of SCOPE. */
492 cp_lookup_transparent_type_loop (const char *name
, const char *scope
,
495 int scope_length
= length
+ cp_find_first_component (scope
+ length
);
498 /* If the current scope is followed by "::", look in the next
500 if (scope
[scope_length
] == ':')
503 = cp_lookup_transparent_type_loop (name
, scope
, scope_length
+ 2);
508 full_name
= alloca (scope_length
+ 2 + strlen (name
) + 1);
509 strncpy (full_name
, scope
, scope_length
);
510 strncpy (full_name
+ scope_length
, "::", 2);
511 strcpy (full_name
+ scope_length
+ 2, name
);
513 return basic_lookup_transparent_type (full_name
);
516 /* Now come functions for dealing with symbols associated to
517 namespaces. (They're used to store the namespaces themselves, not
518 objects that live in the namespaces.) These symbols come in two
519 varieties: if we run into a DW_TAG_namespace DIE, then we know that
520 we have a namespace, so dwarf2read.c creates a symbol for it just
521 like normal. But, unfortunately, versions of GCC through at least
522 3.3 don't generate those DIE's. Our solution is to try to guess
523 their existence by looking at demangled names. This might cause us
524 to misidentify classes as namespaces, however. So we put those
525 symbols in a special block (one per objfile), and we only search
526 that block as a last resort. */
528 /* FIXME: carlton/2003-06-12: Once versions of GCC that generate
529 DW_TAG_namespace have been out for a year or two, we should get rid
530 of all of this "possible namespace" nonsense. */
532 /* Allocate everything necessary for the possible namespace block
533 associated to OBJFILE. */
536 initialize_namespace_symtab (struct objfile
*objfile
)
538 struct symtab
*namespace_symtab
;
539 struct blockvector
*bv
;
542 namespace_symtab
= allocate_symtab ("<<C++-namespaces>>", objfile
);
543 namespace_symtab
->language
= language_cplus
;
544 namespace_symtab
->free_code
= free_nothing
;
545 namespace_symtab
->dirname
= NULL
;
547 bv
= obstack_alloc (&objfile
->objfile_obstack
,
548 sizeof (struct blockvector
)
549 + FIRST_LOCAL_BLOCK
* sizeof (struct block
*));
550 BLOCKVECTOR_NBLOCKS (bv
) = FIRST_LOCAL_BLOCK
+ 1;
551 BLOCKVECTOR (namespace_symtab
) = bv
;
553 /* Allocate empty GLOBAL_BLOCK and STATIC_BLOCK. */
555 bl
= allocate_block (&objfile
->objfile_obstack
);
556 BLOCK_DICT (bl
) = dict_create_linear (&objfile
->objfile_obstack
,
558 BLOCKVECTOR_BLOCK (bv
, GLOBAL_BLOCK
) = bl
;
559 bl
= allocate_block (&objfile
->objfile_obstack
);
560 BLOCK_DICT (bl
) = dict_create_linear (&objfile
->objfile_obstack
,
562 BLOCKVECTOR_BLOCK (bv
, STATIC_BLOCK
) = bl
;
564 /* Allocate the possible namespace block; we put it where the first
565 local block will live, though I don't think there's any need to
566 pretend that it's actually a local block (e.g. by setting
567 BLOCK_SUPERBLOCK appropriately). We don't use the global or
568 static block because we don't want it searched during the normal
569 search of all global/static blocks in lookup_symbol: we only want
570 it used as a last resort. */
572 /* NOTE: carlton/2003-09-11: I considered not associating the fake
573 symbols to a block/symtab at all. But that would cause problems
574 with lookup_symbol's SYMTAB argument and with block_found, so
575 having a symtab/block for this purpose seems like the best
578 bl
= allocate_block (&objfile
->objfile_obstack
);
579 BLOCK_DICT (bl
) = dict_create_hashed_expandable ();
580 BLOCKVECTOR_BLOCK (bv
, FIRST_LOCAL_BLOCK
) = bl
;
582 namespace_symtab
->free_func
= free_namespace_block
;
584 objfile
->cp_namespace_symtab
= namespace_symtab
;
587 /* Locate the possible namespace block associated to OBJFILE,
588 allocating it if necessary. */
590 static struct block
*
591 get_possible_namespace_block (struct objfile
*objfile
)
593 if (objfile
->cp_namespace_symtab
== NULL
)
594 initialize_namespace_symtab (objfile
);
596 return BLOCKVECTOR_BLOCK (BLOCKVECTOR (objfile
->cp_namespace_symtab
),
600 /* Free the dictionary associated to the possible namespace block. */
603 free_namespace_block (struct symtab
*symtab
)
605 struct block
*possible_namespace_block
;
607 possible_namespace_block
= BLOCKVECTOR_BLOCK (BLOCKVECTOR (symtab
),
609 gdb_assert (possible_namespace_block
!= NULL
);
610 dict_free (BLOCK_DICT (possible_namespace_block
));
613 /* Ensure that there are symbols in the possible namespace block
614 associated to OBJFILE for all initial substrings of NAME that look
615 like namespaces or classes. NAME should end in a member variable:
616 it shouldn't consist solely of namespaces. */
619 cp_check_possible_namespace_symbols (const char *name
, struct objfile
*objfile
)
621 check_possible_namespace_symbols_loop (name
,
622 cp_find_first_component (name
),
626 /* This is a helper loop for cp_check_possible_namespace_symbols; it
627 ensures that there are symbols in the possible namespace block
628 associated to OBJFILE for all namespaces that are initial
629 substrings of NAME of length at least LEN. It returns 1 if a
630 previous loop had already created the shortest such symbol and 0
633 This function assumes that if there is already a symbol associated
634 to a substring of NAME of a given length, then there are already
635 symbols associated to all substrings of NAME whose length is less
636 than that length. So if cp_check_possible_namespace_symbols has
637 been called once with argument "A::B::C::member", then that will
638 create symbols "A", "A::B", and "A::B::C". If it is then later
639 called with argument "A::B::D::member", then the new call will
640 generate a new symbol for "A::B::D", but once it sees that "A::B"
641 has already been created, it doesn't bother checking to see if "A"
642 has also been created. */
645 check_possible_namespace_symbols_loop (const char *name
, int len
,
646 struct objfile
*objfile
)
648 if (name
[len
] == ':')
651 int next_len
= len
+ 2;
653 next_len
+= cp_find_first_component (name
+ next_len
);
654 done
= check_possible_namespace_symbols_loop (name
, next_len
,
658 done
= check_one_possible_namespace_symbol (name
, len
, objfile
);
666 /* Check to see if there's already a possible namespace symbol in
667 OBJFILE whose name is the initial substring of NAME of length LEN.
668 If not, create one and return 0; otherwise, return 1. */
671 check_one_possible_namespace_symbol (const char *name
, int len
,
672 struct objfile
*objfile
)
674 struct block
*block
= get_possible_namespace_block (objfile
);
675 char *name_copy
= alloca (len
+ 1);
678 memcpy (name_copy
, name
, len
);
679 name_copy
[len
] = '\0';
680 sym
= lookup_block_symbol (block
, name_copy
, NULL
, VAR_DOMAIN
);
686 type
= init_type (TYPE_CODE_NAMESPACE
, 0, 0, name_copy
, objfile
);
688 TYPE_TAG_NAME (type
) = TYPE_NAME (type
);
690 sym
= obstack_alloc (&objfile
->objfile_obstack
, sizeof (struct symbol
));
691 memset (sym
, 0, sizeof (struct symbol
));
692 SYMBOL_LANGUAGE (sym
) = language_cplus
;
693 /* Note that init_type copied the name to the objfile's
695 SYMBOL_SET_NAMES (sym
, TYPE_NAME (type
), len
, 0, objfile
);
696 SYMBOL_CLASS (sym
) = LOC_TYPEDEF
;
697 SYMBOL_TYPE (sym
) = type
;
698 SYMBOL_DOMAIN (sym
) = VAR_DOMAIN
;
700 dict_add_symbol (BLOCK_DICT (block
), sym
);
708 /* Look for a symbol named NAME in all the possible namespace blocks.
709 If one is found, return it. */
711 static struct symbol
*
712 lookup_possible_namespace_symbol (const char *name
)
714 struct objfile
*objfile
;
716 ALL_OBJFILES (objfile
)
720 sym
= lookup_block_symbol (get_possible_namespace_block (objfile
),
721 name
, NULL
, VAR_DOMAIN
);
730 /* Print out all the possible namespace symbols. */
733 maintenance_cplus_namespace (char *args
, int from_tty
)
735 struct objfile
*objfile
;
736 printf_unfiltered (_("Possible namespaces:\n"));
737 ALL_OBJFILES (objfile
)
739 struct dict_iterator iter
;
742 ALL_BLOCK_SYMBOLS (get_possible_namespace_block (objfile
), iter
, sym
)
744 printf_unfiltered ("%s\n", SYMBOL_PRINT_NAME (sym
));
749 /* Provide a prototype to silence -Wmissing-prototypes. */
750 extern initialize_file_ftype _initialize_cp_namespace
;
753 _initialize_cp_namespace (void)
755 add_cmd ("namespace", class_maintenance
, maintenance_cplus_namespace
,
756 _("Print the list of possible C++ namespaces."),
757 &maint_cplus_cmd_list
);