/* Helper routines for C++ support in GDB.
- Copyright 2003 Free Software Foundation, Inc.
+ Copyright (C) 2003, 2004, 2007 Free Software Foundation, Inc.
Contributed by David Carlton and by Kealia, Inc.
You should have received a copy of the GNU General Public License
along with this program; if not, write to the Free Software
- Foundation, Inc., 59 Temple Place - Suite 330,
- Boston, MA 02111-1307, USA. */
+ Foundation, Inc., 51 Franklin Street, Fifth Floor,
+ Boston, MA 02110-1301, USA. */
#include "defs.h"
#include "cp-support.h"
#include "symfile.h"
#include "gdb_assert.h"
#include "block.h"
+#include "objfiles.h"
+#include "gdbtypes.h"
+#include "dictionary.h"
+#include "command.h"
+#include "frame.h"
-/* When set, the file that we're processing seems to have debugging
- info for C++ namespaces, so cp-namespace.c shouldn't try to guess
- namespace info itself. */
+/* When set, the file that we're processing is known to have debugging
+ info for C++ namespaces. */
+
+/* NOTE: carlton/2004-01-13: No currently released version of GCC (the
+ latest of which is 3.3.x at the time of this writing) produces this
+ debug info. GCC 3.4 should, however. */
unsigned char processing_has_namespace_info;
-/* If processing_has_namespace_info is nonzero, this string should
- contain the name of the current namespace. The string is
- temporary; copy it if you need it. */
+/* This contains our best guess as to the name of the current
+ enclosing namespace(s)/class(es), if any. For example, if we're
+ within the method foo() in the following code:
+
+ namespace N {
+ class C {
+ void foo () {
+ }
+ };
+ }
+
+ then processing_current_prefix should be set to "N::C". If
+ processing_has_namespace_info is false, then this variable might
+ not be reliable. */
-const char *processing_current_namespace;
+const char *processing_current_prefix;
/* List of using directives that are active in the current file. */
struct symtab **symtab,
int anonymous_namespace);
+static struct type *cp_lookup_transparent_type_loop (const char *name,
+ const char *scope,
+ int scope_len);
+
+static void initialize_namespace_symtab (struct objfile *objfile);
+
+static struct block *get_possible_namespace_block (struct objfile *objfile);
+
+static void free_namespace_block (struct symtab *symtab);
+
+static int check_possible_namespace_symbols_loop (const char *name,
+ int len,
+ struct objfile *objfile);
+
+static int check_one_possible_namespace_symbol (const char *name,
+ int len,
+ struct objfile *objfile);
+
+static
+struct symbol *lookup_possible_namespace_symbol (const char *name,
+ struct symtab **symtab);
+
+static void maintenance_cplus_namespace (char *args, int from_tty);
+
/* Set up support for dealing with C++ namespace info in the current
symtab. */
if (processing_has_namespace_info)
{
block_set_scope
- (block, obsavestring (processing_current_namespace,
- strlen (processing_current_namespace),
+ (block, obsavestring (processing_current_prefix,
+ strlen (processing_current_prefix),
obstack),
obstack);
}
cp_lookup_symbol_nonlocal.
For example, if we're within a function A::B::f and looking for a
- symbol f, this will get called with NAME = "f", SCOPE = "A::B", and
+ symbol x, this will get called with NAME = "x", SCOPE = "A::B", and
SCOPE_LEN = 0. It then calls itself with NAME and SCOPE the same,
but with SCOPE_LEN = 1. And then it calls itself with NAME and
SCOPE the same, but with SCOPE_LEN = 4. This third call looks for
const struct block *global_block = block_global_block (block);
if (global_block != NULL)
- return lookup_symbol_aux_block (name, linkage_name, global_block,
- domain, symtab);
- else
- return NULL;
+ sym = lookup_symbol_aux_block (name, linkage_name, global_block,
+ domain, symtab);
+ }
+ else
+ {
+ sym = lookup_symbol_global (name, linkage_name, domain, symtab);
+ }
+
+ if (sym != NULL)
+ return sym;
+
+ /* Now call "lookup_possible_namespace_symbol". Symbols in here
+ claim to be associated to namespaces, but this claim might be
+ incorrect: the names in question might actually correspond to
+ classes instead of namespaces. But if they correspond to
+ classes, then we should have found a match for them above. So if
+ we find them now, they should be genuine. */
+
+ /* FIXME: carlton/2003-06-12: This is a hack and should eventually
+ be deleted: see comments below. */
+
+ if (domain == VAR_DOMAIN)
+ {
+ sym = lookup_possible_namespace_symbol (name, symtab);
+ if (sym != NULL)
+ return sym;
+ }
+
+ return NULL;
+}
+
+/* Look up a type named NESTED_NAME that is nested inside the C++
+ class or namespace given by PARENT_TYPE, from within the context
+ given by BLOCK. Return NULL if there is no such nested type. */
+
+struct type *
+cp_lookup_nested_type (struct type *parent_type,
+ const char *nested_name,
+ const struct block *block)
+{
+ switch (TYPE_CODE (parent_type))
+ {
+ case TYPE_CODE_STRUCT:
+ case TYPE_CODE_NAMESPACE:
+ {
+ /* NOTE: carlton/2003-11-10: We don't treat C++ class members
+ of classes like, say, data or function members. Instead,
+ they're just represented by symbols whose names are
+ qualified by the name of the surrounding class. This is
+ just like members of namespaces; in particular,
+ lookup_symbol_namespace works when looking them up. */
+
+ const char *parent_name = TYPE_TAG_NAME (parent_type);
+ struct symbol *sym = cp_lookup_symbol_namespace (parent_name,
+ nested_name,
+ NULL,
+ block,
+ VAR_DOMAIN,
+ NULL);
+ if (sym == NULL || SYMBOL_CLASS (sym) != LOC_TYPEDEF)
+ return NULL;
+ else
+ return SYMBOL_TYPE (sym);
+ }
+ default:
+ internal_error (__FILE__, __LINE__,
+ _("cp_lookup_nested_type called on a non-aggregate type."));
+ }
+}
+
+/* The C++-version of lookup_transparent_type. */
+
+/* FIXME: carlton/2004-01-16: The problem that this is trying to
+ address is that, unfortunately, sometimes NAME is wrong: it may not
+ include the name of namespaces enclosing the type in question.
+ lookup_transparent_type gets called when the the type in question
+ is a declaration, and we're trying to find its definition; but, for
+ declarations, our type name deduction mechanism doesn't work.
+ There's nothing we can do to fix this in general, I think, in the
+ absence of debug information about namespaces (I've filed PR
+ gdb/1511 about this); until such debug information becomes more
+ prevalent, one heuristic which sometimes looks is to search for the
+ definition in namespaces containing the current namespace.
+
+ We should delete this functions once the appropriate debug
+ information becomes more widespread. (GCC 3.4 will be the first
+ released version of GCC with such information.) */
+
+struct type *
+cp_lookup_transparent_type (const char *name)
+{
+ /* First, try the honest way of looking up the definition. */
+ struct type *t = basic_lookup_transparent_type (name);
+ const char *scope;
+
+ if (t != NULL)
+ return t;
+
+ /* If that doesn't work and we're within a namespace, look there
+ instead. */
+ scope = block_scope (get_selected_block (0));
+
+ if (scope[0] == '\0')
+ return NULL;
+
+ return cp_lookup_transparent_type_loop (name, scope, 0);
+}
+
+/* Lookup the the type definition associated to NAME in
+ namespaces/classes containing SCOPE whose name is strictly longer
+ than LENGTH. LENGTH must be the index of the start of a
+ component of SCOPE. */
+
+static struct type *
+cp_lookup_transparent_type_loop (const char *name, const char *scope,
+ int length)
+{
+ int scope_length = length + cp_find_first_component (scope + length);
+ char *full_name;
+
+ /* If the current scope is followed by "::", look in the next
+ component. */
+ if (scope[scope_length] == ':')
+ {
+ struct type *retval
+ = cp_lookup_transparent_type_loop (name, scope, scope_length + 2);
+ if (retval != NULL)
+ return retval;
+ }
+
+ full_name = alloca (scope_length + 2 + strlen (name) + 1);
+ strncpy (full_name, scope, scope_length);
+ strncpy (full_name + scope_length, "::", 2);
+ strcpy (full_name + scope_length + 2, name);
+
+ return basic_lookup_transparent_type (full_name);
+}
+
+/* Now come functions for dealing with symbols associated to
+ namespaces. (They're used to store the namespaces themselves, not
+ objects that live in the namespaces.) These symbols come in two
+ varieties: if we run into a DW_TAG_namespace DIE, then we know that
+ we have a namespace, so dwarf2read.c creates a symbol for it just
+ like normal. But, unfortunately, versions of GCC through at least
+ 3.3 don't generate those DIE's. Our solution is to try to guess
+ their existence by looking at demangled names. This might cause us
+ to misidentify classes as namespaces, however. So we put those
+ symbols in a special block (one per objfile), and we only search
+ that block as a last resort. */
+
+/* FIXME: carlton/2003-06-12: Once versions of GCC that generate
+ DW_TAG_namespace have been out for a year or two, we should get rid
+ of all of this "possible namespace" nonsense. */
+
+/* Allocate everything necessary for the possible namespace block
+ associated to OBJFILE. */
+
+static void
+initialize_namespace_symtab (struct objfile *objfile)
+{
+ struct symtab *namespace_symtab;
+ struct blockvector *bv;
+ struct block *bl;
+
+ namespace_symtab = allocate_symtab ("<<C++-namespaces>>", objfile);
+ namespace_symtab->language = language_cplus;
+ namespace_symtab->free_code = free_nothing;
+ namespace_symtab->dirname = NULL;
+
+ bv = obstack_alloc (&objfile->objfile_obstack,
+ sizeof (struct blockvector)
+ + FIRST_LOCAL_BLOCK * sizeof (struct block *));
+ BLOCKVECTOR_NBLOCKS (bv) = FIRST_LOCAL_BLOCK + 1;
+ BLOCKVECTOR (namespace_symtab) = bv;
+
+ /* Allocate empty GLOBAL_BLOCK and STATIC_BLOCK. */
+
+ bl = allocate_block (&objfile->objfile_obstack);
+ BLOCK_DICT (bl) = dict_create_linear (&objfile->objfile_obstack,
+ NULL);
+ BLOCKVECTOR_BLOCK (bv, GLOBAL_BLOCK) = bl;
+ bl = allocate_block (&objfile->objfile_obstack);
+ BLOCK_DICT (bl) = dict_create_linear (&objfile->objfile_obstack,
+ NULL);
+ BLOCKVECTOR_BLOCK (bv, STATIC_BLOCK) = bl;
+
+ /* Allocate the possible namespace block; we put it where the first
+ local block will live, though I don't think there's any need to
+ pretend that it's actually a local block (e.g. by setting
+ BLOCK_SUPERBLOCK appropriately). We don't use the global or
+ static block because we don't want it searched during the normal
+ search of all global/static blocks in lookup_symbol: we only want
+ it used as a last resort. */
+
+ /* NOTE: carlton/2003-09-11: I considered not associating the fake
+ symbols to a block/symtab at all. But that would cause problems
+ with lookup_symbol's SYMTAB argument and with block_found, so
+ having a symtab/block for this purpose seems like the best
+ solution for now. */
+
+ bl = allocate_block (&objfile->objfile_obstack);
+ BLOCK_DICT (bl) = dict_create_hashed_expandable ();
+ BLOCKVECTOR_BLOCK (bv, FIRST_LOCAL_BLOCK) = bl;
+
+ namespace_symtab->free_func = free_namespace_block;
+
+ objfile->cp_namespace_symtab = namespace_symtab;
+}
+
+/* Locate the possible namespace block associated to OBJFILE,
+ allocating it if necessary. */
+
+static struct block *
+get_possible_namespace_block (struct objfile *objfile)
+{
+ if (objfile->cp_namespace_symtab == NULL)
+ initialize_namespace_symtab (objfile);
+
+ return BLOCKVECTOR_BLOCK (BLOCKVECTOR (objfile->cp_namespace_symtab),
+ FIRST_LOCAL_BLOCK);
+}
+
+/* Free the dictionary associated to the possible namespace block. */
+
+static void
+free_namespace_block (struct symtab *symtab)
+{
+ struct block *possible_namespace_block;
+
+ possible_namespace_block = BLOCKVECTOR_BLOCK (BLOCKVECTOR (symtab),
+ FIRST_LOCAL_BLOCK);
+ gdb_assert (possible_namespace_block != NULL);
+ dict_free (BLOCK_DICT (possible_namespace_block));
+}
+
+/* Ensure that there are symbols in the possible namespace block
+ associated to OBJFILE for all initial substrings of NAME that look
+ like namespaces or classes. NAME should end in a member variable:
+ it shouldn't consist solely of namespaces. */
+
+void
+cp_check_possible_namespace_symbols (const char *name, struct objfile *objfile)
+{
+ check_possible_namespace_symbols_loop (name,
+ cp_find_first_component (name),
+ objfile);
+}
+
+/* This is a helper loop for cp_check_possible_namespace_symbols; it
+ ensures that there are symbols in the possible namespace block
+ associated to OBJFILE for all namespaces that are initial
+ substrings of NAME of length at least LEN. It returns 1 if a
+ previous loop had already created the shortest such symbol and 0
+ otherwise.
+
+ This function assumes that if there is already a symbol associated
+ to a substring of NAME of a given length, then there are already
+ symbols associated to all substrings of NAME whose length is less
+ than that length. So if cp_check_possible_namespace_symbols has
+ been called once with argument "A::B::C::member", then that will
+ create symbols "A", "A::B", and "A::B::C". If it is then later
+ called with argument "A::B::D::member", then the new call will
+ generate a new symbol for "A::B::D", but once it sees that "A::B"
+ has already been created, it doesn't bother checking to see if "A"
+ has also been created. */
+
+static int
+check_possible_namespace_symbols_loop (const char *name, int len,
+ struct objfile *objfile)
+{
+ if (name[len] == ':')
+ {
+ int done;
+ int next_len = len + 2;
+
+ next_len += cp_find_first_component (name + next_len);
+ done = check_possible_namespace_symbols_loop (name, next_len,
+ objfile);
+
+ if (!done)
+ done = check_one_possible_namespace_symbol (name, len, objfile);
+
+ return done;
+ }
+ else
+ return 0;
+}
+
+/* Check to see if there's already a possible namespace symbol in
+ OBJFILE whose name is the initial substring of NAME of length LEN.
+ If not, create one and return 0; otherwise, return 1. */
+
+static int
+check_one_possible_namespace_symbol (const char *name, int len,
+ struct objfile *objfile)
+{
+ struct block *block = get_possible_namespace_block (objfile);
+ char *name_copy = alloca (len + 1);
+ struct symbol *sym;
+
+ memcpy (name_copy, name, len);
+ name_copy[len] = '\0';
+ sym = lookup_block_symbol (block, name_copy, NULL, VAR_DOMAIN);
+
+ if (sym == NULL)
+ {
+ struct type *type;
+ name_copy = obsavestring (name, len, &objfile->objfile_obstack);
+
+ type = init_type (TYPE_CODE_NAMESPACE, 0, 0, name_copy, objfile);
+
+ TYPE_TAG_NAME (type) = TYPE_NAME (type);
+
+ sym = obstack_alloc (&objfile->objfile_obstack, sizeof (struct symbol));
+ memset (sym, 0, sizeof (struct symbol));
+ SYMBOL_LANGUAGE (sym) = language_cplus;
+ SYMBOL_SET_NAMES (sym, name_copy, len, objfile);
+ SYMBOL_CLASS (sym) = LOC_TYPEDEF;
+ SYMBOL_TYPE (sym) = type;
+ SYMBOL_DOMAIN (sym) = VAR_DOMAIN;
+
+ dict_add_symbol (BLOCK_DICT (block), sym);
+
+ return 0;
}
else
+ return 1;
+}
+
+/* Look for a symbol named NAME in all the possible namespace blocks.
+ If one is found, return it; if SYMTAB is non-NULL, set *SYMTAB to
+ equal the symtab where it was found. */
+
+static struct symbol *
+lookup_possible_namespace_symbol (const char *name, struct symtab **symtab)
+{
+ struct objfile *objfile;
+
+ ALL_OBJFILES (objfile)
+ {
+ struct symbol *sym;
+
+ sym = lookup_block_symbol (get_possible_namespace_block (objfile),
+ name, NULL, VAR_DOMAIN);
+
+ if (sym != NULL)
+ {
+ if (symtab != NULL)
+ *symtab = objfile->cp_namespace_symtab;
+
+ return sym;
+ }
+ }
+
+ return NULL;
+}
+
+/* Print out all the possible namespace symbols. */
+
+static void
+maintenance_cplus_namespace (char *args, int from_tty)
+{
+ struct objfile *objfile;
+ printf_unfiltered (_("Possible namespaces:\n"));
+ ALL_OBJFILES (objfile)
{
- return lookup_symbol_global (name, linkage_name, domain, symtab);
+ struct dict_iterator iter;
+ struct symbol *sym;
+
+ ALL_BLOCK_SYMBOLS (get_possible_namespace_block (objfile), iter, sym)
+ {
+ printf_unfiltered ("%s\n", SYMBOL_PRINT_NAME (sym));
+ }
}
}
+
+void
+_initialize_cp_namespace (void)
+{
+ add_cmd ("namespace", class_maintenance, maintenance_cplus_namespace,
+ _("Print the list of possible C++ namespaces."),
+ &maint_cplus_cmd_list);
+}