binutils-gdb/gdb/cp-valprint.c
Peter Schauer 39cb3d0488 * stabsread.c (read_member_functions): Initialize domain for stubbed
member functions to avoid gdb core dumps when printing pointers
	to member functions.
	* cp-valprint.c (cp_print_class_method): Check for stubbed member
	functions.
1993-04-14 19:53:11 +00:00

469 lines
12 KiB
C

/* Support for printing C++ values for GDB, the GNU debugger.
Copyright 1986, 1988, 1989, 1991 Free Software Foundation, Inc.
This file is part of GDB.
This program is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation; either version 2 of the License, or
(at your option) any later version.
This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.
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., 675 Mass Ave, Cambridge, MA 02139, USA. */
#include "defs.h"
#include "obstack.h"
#include "symtab.h"
#include "gdbtypes.h"
#include "expression.h"
#include "value.h"
#include "command.h"
#include "gdbcmd.h"
#include "demangle.h"
int vtblprint; /* Controls printing of vtbl's */
int objectprint; /* Controls looking up an object's derived type
using what we find in its vtables. */
struct obstack dont_print_obstack;
static void
cplus_print_value PARAMS ((struct type *, char *, FILE *, int, int,
enum val_prettyprint, struct type **));
/* BEGIN-FIXME: Hooks into typeprint.c, find a better home for prototypes. */
extern void
c_type_print_base PARAMS ((struct type *, FILE *, int, int));
extern void
c_type_print_varspec_prefix PARAMS ((struct type *, FILE *, int, int));
extern void
cp_type_print_method_args PARAMS ((struct type **, char *, char *, int,
FILE *));
extern struct obstack dont_print_obstack;
/* END-FIXME */
/* BEGIN-FIXME: Hooks into c-valprint.c */
extern int
c_val_print PARAMS ((struct type *, char *, CORE_ADDR, FILE *, int, int, int,
enum val_prettyprint));
/* END-FIXME */
void
cp_print_class_method (valaddr, type, stream)
char *valaddr;
struct type *type;
FILE *stream;
{
struct type *domain;
struct fn_field *f;
int j;
int len2;
int offset;
char *kind = "";
CORE_ADDR addr;
struct symbol *sym;
unsigned len;
unsigned int i;
domain = TYPE_DOMAIN_TYPE (TYPE_TARGET_TYPE (type));
addr = unpack_pointer (lookup_pointer_type (builtin_type_void), valaddr);
if (METHOD_PTR_IS_VIRTUAL (addr))
{
offset = METHOD_PTR_TO_VOFFSET (addr);
len = TYPE_NFN_FIELDS (domain);
for (i = 0; i < len; i++)
{
f = TYPE_FN_FIELDLIST1 (domain, i);
len2 = TYPE_FN_FIELDLIST_LENGTH (domain, i);
for (j = 0; j < len2; j++)
{
QUIT;
if (TYPE_FN_FIELD_VOFFSET (f, j) == offset)
{
kind = "virtual ";
goto common;
}
}
}
}
else
{
sym = find_pc_function (addr);
if (sym == 0)
{
error ("invalid pointer to member function");
}
len = TYPE_NFN_FIELDS (domain);
for (i = 0; i < len; i++)
{
f = TYPE_FN_FIELDLIST1 (domain, i);
len2 = TYPE_FN_FIELDLIST_LENGTH (domain, i);
for (j = 0; j < len2; j++)
{
QUIT;
if (TYPE_FN_FIELD_STUB (f, j))
check_stub_method (domain, i, j);
if (STREQ (SYMBOL_NAME (sym), TYPE_FN_FIELD_PHYSNAME (f, j)))
{
goto common;
}
}
}
}
common:
if (i < len)
{
fprintf_filtered (stream, "&");
c_type_print_varspec_prefix (TYPE_FN_FIELD_TYPE (f, j), stream, 0, 0);
fprintf (stream, kind);
if (TYPE_FN_FIELD_PHYSNAME (f, j)[0] == '_'
&& TYPE_FN_FIELD_PHYSNAME (f, j)[1] == CPLUS_MARKER)
{
cp_type_print_method_args (TYPE_FN_FIELD_ARGS (f, j) + 1, "~",
TYPE_FN_FIELDLIST_NAME (domain, i),
0, stream);
}
else
{
cp_type_print_method_args (TYPE_FN_FIELD_ARGS (f, j), "",
TYPE_FN_FIELDLIST_NAME (domain, i),
0, stream);
}
}
else
{
fprintf_filtered (stream, "(");
type_print (type, "", stream, -1);
fprintf_filtered (stream, ") %d", (int) addr >> 3);
}
}
/* Return truth value for assertion that TYPE is of the type
"pointer to virtual function". */
int
cp_is_vtbl_ptr_type(type)
struct type *type;
{
char *typename = type_name_no_tag (type);
static const char vtbl_ptr_name[] =
{ CPLUS_MARKER,'v','t','b','l','_','p','t','r','_','t','y','p','e', 0 };
return (typename != NULL && STREQ(typename, vtbl_ptr_name));
}
/* Return truth value for the assertion that TYPE is of the type
"pointer to virtual function table". */
int
cp_is_vtbl_member(type)
struct type *type;
{
if (TYPE_CODE (type) == TYPE_CODE_PTR)
type = TYPE_TARGET_TYPE (type);
else
return 0;
if (TYPE_CODE (type) == TYPE_CODE_ARRAY
&& TYPE_CODE (TYPE_TARGET_TYPE (type)) == TYPE_CODE_STRUCT)
/* Virtual functions tables are full of pointers to virtual functions. */
return cp_is_vtbl_ptr_type (TYPE_TARGET_TYPE (type));
return 0;
}
/* Mutually recursive subroutines of cplus_print_value and c_val_print to
print out a structure's fields: cp_print_value_fields and cplus_print_value.
TYPE, VALADDR, STREAM, RECURSE, and PRETTY have the
same meanings as in cplus_print_value and c_val_print.
DONT_PRINT is an array of baseclass types that we
should not print, or zero if called from top level. */
void
cp_print_value_fields (type, valaddr, stream, format, recurse, pretty,
dont_print)
struct type *type;
char *valaddr;
FILE *stream;
int format;
int recurse;
enum val_prettyprint pretty;
struct type **dont_print;
{
int i, len, n_baseclasses;
check_stub_type (type);
fprintf_filtered (stream, "{");
len = TYPE_NFIELDS (type);
n_baseclasses = TYPE_N_BASECLASSES (type);
/* Print out baseclasses such that we don't print
duplicates of virtual baseclasses. */
if (n_baseclasses > 0)
cplus_print_value (type, valaddr, stream, format, recurse+1, pretty,
dont_print);
if (!len && n_baseclasses == 1)
fprintf_filtered (stream, "<No data fields>");
else
{
extern int inspect_it;
int fields_seen = 0;
for (i = n_baseclasses; i < len; i++)
{
/* Check if static field */
if (TYPE_FIELD_STATIC (type, i))
continue;
if (fields_seen)
fprintf_filtered (stream, ", ");
else if (n_baseclasses > 0)
{
if (pretty)
{
fprintf_filtered (stream, "\n");
print_spaces_filtered (2 + 2 * recurse, stream);
fputs_filtered ("members of ", stream);
fputs_filtered (type_name_no_tag (type), stream);
fputs_filtered (": ", stream);
}
}
fields_seen = 1;
if (pretty)
{
fprintf_filtered (stream, "\n");
print_spaces_filtered (2 + 2 * recurse, stream);
}
else
{
wrap_here (n_spaces (2 + 2 * recurse));
}
if (inspect_it)
{
if (TYPE_CODE (TYPE_FIELD_TYPE (type, i)) == TYPE_CODE_PTR)
fputs_filtered ("\"( ptr \"", stream);
else
fputs_filtered ("\"( nodef \"", stream);
fprintf_symbol_filtered (stream, TYPE_FIELD_NAME (type, i),
language_cplus,
DMGL_PARAMS | DMGL_ANSI);
fputs_filtered ("\" \"", stream);
fprintf_symbol_filtered (stream, TYPE_FIELD_NAME (type, i),
language_cplus,
DMGL_PARAMS | DMGL_ANSI);
fputs_filtered ("\") \"", stream);
}
else
{
fprintf_symbol_filtered (stream, TYPE_FIELD_NAME (type, i),
language_cplus,
DMGL_PARAMS | DMGL_ANSI);
fputs_filtered (" = ", stream);
}
if (TYPE_FIELD_PACKED (type, i))
{
value v;
/* Bitfields require special handling, especially due to byte
order problems. */
v = value_from_longest (TYPE_FIELD_TYPE (type, i),
unpack_field_as_long (type, valaddr, i));
c_val_print (TYPE_FIELD_TYPE (type, i), VALUE_CONTENTS (v), 0,
stream, format, 0, recurse + 1, pretty);
}
else
{
c_val_print (TYPE_FIELD_TYPE (type, i),
valaddr + TYPE_FIELD_BITPOS (type, i) / 8,
0, stream, format, 0, recurse + 1, pretty);
}
}
if (pretty)
{
fprintf_filtered (stream, "\n");
print_spaces_filtered (2 * recurse, stream);
}
}
fprintf_filtered (stream, "}");
}
/* Special val_print routine to avoid printing multiple copies of virtual
baseclasses. */
static void
cplus_print_value (type, valaddr, stream, format, recurse, pretty, dont_print)
struct type *type;
char *valaddr;
FILE *stream;
int format;
int recurse;
enum val_prettyprint pretty;
struct type **dont_print;
{
struct obstack tmp_obstack;
struct type **last_dont_print
= (struct type **)obstack_next_free (&dont_print_obstack);
int i, n_baseclasses = TYPE_N_BASECLASSES (type);
if (dont_print == 0)
{
/* If we're at top level, carve out a completely fresh
chunk of the obstack and use that until this particular
invocation returns. */
tmp_obstack = dont_print_obstack;
/* Bump up the high-water mark. Now alpha is omega. */
obstack_finish (&dont_print_obstack);
}
for (i = 0; i < n_baseclasses; i++)
{
char *baddr;
int err;
if (BASETYPE_VIA_VIRTUAL (type, i))
{
struct type **first_dont_print
= (struct type **)obstack_base (&dont_print_obstack);
int j = (struct type **)obstack_next_free (&dont_print_obstack)
- first_dont_print;
while (--j >= 0)
if (TYPE_BASECLASS (type, i) == first_dont_print[j])
goto flush_it;
obstack_ptr_grow (&dont_print_obstack, TYPE_BASECLASS (type, i));
}
/* Fix to use baseclass_offset instead. FIXME */
baddr = baseclass_addr (type, i, valaddr, 0, &err);
if (err == 0 && baddr == 0)
error ("could not find virtual baseclass `%s'\n",
type_name_no_tag (TYPE_BASECLASS (type, i)));
if (pretty)
{
fprintf_filtered (stream, "\n");
print_spaces_filtered (2 * recurse, stream);
}
fputs_filtered ("<", stream);
fputs_filtered (type_name_no_tag (TYPE_BASECLASS (type, i)), stream);
fputs_filtered ("> = ", stream);
if (err != 0)
fprintf_filtered (stream, "<invalid address 0x%x>", baddr);
else
cp_print_value_fields (TYPE_BASECLASS (type, i), baddr, stream, format,
recurse, pretty,
(struct type **) obstack_base (&dont_print_obstack));
fputs_filtered (", ", stream);
flush_it:
;
}
if (dont_print == 0)
{
/* Free the space used to deal with the printing
of this type from top level. */
obstack_free (&dont_print_obstack, last_dont_print);
/* Reset watermark so that we can continue protecting
ourselves from whatever we were protecting ourselves. */
dont_print_obstack = tmp_obstack;
}
}
void
cp_print_class_member (valaddr, domain, stream, prefix)
char *valaddr;
struct type *domain;
FILE *stream;
char *prefix;
{
/* VAL is a byte offset into the structure type DOMAIN.
Find the name of the field for that offset and
print it. */
int extra = 0;
int bits = 0;
register unsigned int i;
unsigned len = TYPE_NFIELDS (domain);
/* @@ Make VAL into bit offset */
LONGEST val = unpack_long (builtin_type_int, valaddr) << 3;
for (i = TYPE_N_BASECLASSES (domain); i < len; i++)
{
int bitpos = TYPE_FIELD_BITPOS (domain, i);
QUIT;
if (val == bitpos)
break;
if (val < bitpos && i != 0)
{
/* Somehow pointing into a field. */
i -= 1;
extra = (val - TYPE_FIELD_BITPOS (domain, i));
if (extra & 0x7)
bits = 1;
else
extra >>= 3;
break;
}
}
if (i < len)
{
char *name;
fprintf_filtered (stream, prefix);
name = type_name_no_tag (domain);
if (name)
fputs_filtered (name, stream);
else
c_type_print_base (domain, stream, 0, 0);
fprintf_filtered (stream, "::");
fputs_filtered (TYPE_FIELD_NAME (domain, i), stream);
if (extra)
fprintf_filtered (stream, " + %d bytes", extra);
if (bits)
fprintf_filtered (stream, " (offset in bits)");
}
else
fprintf_filtered (stream, "%d", val >> 3);
}
void
_initialize_cp_valprint ()
{
add_show_from_set
(add_set_cmd ("vtbl", class_support, var_boolean, (char *)&vtblprint,
"Set printing of C++ virtual function tables.",
&setprintlist),
&showprintlist);
add_show_from_set
(add_set_cmd ("object", class_support, var_boolean, (char *)&objectprint,
"Set printing of object's derived type based on vtable info.",
&setprintlist),
&showprintlist);
/* Give people the defaults which they are used to. */
objectprint = 0;
vtblprint = 0;
obstack_begin (&dont_print_obstack, 32 * sizeof (struct type *));
}