binutils-gdb/gdb/jv-valprint.c
Pedro Alves 686d4defdf Print nonexisting/optimized out static fields gracefully.
With:

 struct static_struct { static int aaa; };
 struct static_struct sss;
 int main () { return 0; }

We get:

 (gdb) p sss
 $1 = {static aaa = <optimized out>}
 (gdb) p sss.aaa
 field aaa is nonexistent or has been optimized out

Note that the "field aaa ..." message is an error being thrown.

GDB is graceful everywhere else when printing optimized out values.
IOW it usually prints an <optimized out> value and puts that in the
value history.  I see no reason for here to be different, more so that
when the print the whole "containing" object (well, it's a static
field, so it's not really a container), we already print <optimized
out>.

After the patch:

 (gdb) p sss
 $1 = {static aaa = <optimized out>}
 (gdb) p sss.aaa
 $2 = <optimized out>

The value_entirely_optimized_out checks are there to preserve
behavior.  Without those, if the static field is a struct/union, GDB
would go and print its fields one by one (and print <optimized out>
for each).

Tested on x86_64 Fedora 17.

gdb/
2013-10-25  Pedro Alves  <palves@redhat.com>

	* cp-valprint.c (cp_print_value_fields): No longer handle a NULL
	static field value.
	(cp_print_static_field): If the value is entirely optimized out,
	print <optimized out> here.
	* jv-valprint.c (java_print_value_fields): No longer handle a NULL
	static field value.
	* p-valprint.c (pascal_object_print_static_field): If the value is
	entirely optimized out, print <optimized out> here.
	* valops.c (do_search_struct_field)
	(value_struct_elt_for_reference): No longer handle a NULL static
	field value.
	* value.c (value_static_field): Return an optimized out value
	instead of NULL.

gdb/testsuite/
2013-10-25  Pedro Alves  <palves@redhat.com>

	* gdb.cp/m-static.exp: Adjust expected output of printing a
	nonexistent or optimized out static field.  Also test printing the
	the "container" object.
2013-10-25 14:03:01 +00:00

538 lines
14 KiB
C

/* Support for printing Java values for GDB, the GNU debugger.
Copyright (C) 1997-2013 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 3 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, see <http://www.gnu.org/licenses/>. */
#include "defs.h"
#include "symtab.h"
#include "gdbtypes.h"
#include "gdbcore.h"
#include "expression.h"
#include "value.h"
#include "demangle.h"
#include "valprint.h"
#include "language.h"
#include "jv-lang.h"
#include "c-lang.h"
#include "annotate.h"
#include "gdb_string.h"
/* Local functions */
void
java_value_print (struct value *val, struct ui_file *stream,
const struct value_print_options *options)
{
struct gdbarch *gdbarch = get_type_arch (value_type (val));
enum bfd_endian byte_order = gdbarch_byte_order (gdbarch);
struct type *type;
CORE_ADDR address;
int i;
const char *name;
struct value_print_options opts;
type = value_type (val);
address = value_address (val);
if (is_object_type (type))
{
CORE_ADDR obj_addr;
struct value *tem = val;
/* Get the run-time type, and cast the object into that. */
while (TYPE_CODE (value_type (tem)) == TYPE_CODE_PTR)
tem = value_ind (tem);
obj_addr = value_address (tem);
if (obj_addr != 0)
{
type = type_from_class (gdbarch, java_class_from_object (val));
type = lookup_pointer_type (type);
val = value_at (type, address);
}
}
if (TYPE_CODE (type) == TYPE_CODE_PTR && !value_logical_not (val))
type_print (TYPE_TARGET_TYPE (type), "", stream, -1);
name = TYPE_TAG_NAME (type);
if (TYPE_CODE (type) == TYPE_CODE_STRUCT && name != NULL
&& (i = strlen (name), name[i - 1] == ']'))
{
gdb_byte buf4[4];
long length;
unsigned int things_printed = 0;
int reps;
struct type *el_type
= java_primitive_type_from_name (gdbarch, name, i - 2);
i = 0;
read_memory (address + get_java_object_header_size (gdbarch), buf4, 4);
length = (long) extract_signed_integer (buf4, 4, byte_order);
fprintf_filtered (stream, "{length: %ld", length);
if (el_type == NULL)
{
CORE_ADDR element;
CORE_ADDR next_element = -1; /* Dummy initial value. */
/* Skip object header and length. */
address += get_java_object_header_size (gdbarch) + 4;
while (i < length && things_printed < options->print_max)
{
gdb_byte *buf;
buf = alloca (gdbarch_ptr_bit (gdbarch) / HOST_CHAR_BIT);
fputs_filtered (", ", stream);
wrap_here (n_spaces (2));
if (i > 0)
element = next_element;
else
{
read_memory (address, buf, sizeof (buf));
address += gdbarch_ptr_bit (gdbarch) / HOST_CHAR_BIT;
/* FIXME: cagney/2003-05-24: Bogus or what. It
pulls a host sized pointer out of the target and
then extracts that as an address (while assuming
that the address is unsigned)! */
element = extract_unsigned_integer (buf, sizeof (buf),
byte_order);
}
for (reps = 1; i + reps < length; reps++)
{
read_memory (address, buf, sizeof (buf));
address += gdbarch_ptr_bit (gdbarch) / HOST_CHAR_BIT;
/* FIXME: cagney/2003-05-24: Bogus or what. It
pulls a host sized pointer out of the target and
then extracts that as an address (while assuming
that the address is unsigned)! */
next_element = extract_unsigned_integer (buf, sizeof (buf),
byte_order);
if (next_element != element)
break;
}
if (reps == 1)
fprintf_filtered (stream, "%d: ", i);
else
fprintf_filtered (stream, "%d..%d: ", i, i + reps - 1);
if (element == 0)
fprintf_filtered (stream, "null");
else
fprintf_filtered (stream, "@%s", paddress (gdbarch, element));
things_printed++;
i += reps;
}
}
else
{
struct value *v = allocate_value (el_type);
struct value *next_v = allocate_value (el_type);
set_value_address (v, (address
+ get_java_object_header_size (gdbarch) + 4));
set_value_address (next_v, value_raw_address (v));
while (i < length && things_printed < options->print_max)
{
fputs_filtered (", ", stream);
wrap_here (n_spaces (2));
if (i > 0)
{
struct value *tmp;
tmp = next_v;
next_v = v;
v = tmp;
}
else
{
set_value_lazy (v, 1);
set_value_offset (v, 0);
}
set_value_offset (next_v, value_offset (v));
for (reps = 1; i + reps < length; reps++)
{
set_value_lazy (next_v, 1);
set_value_offset (next_v, value_offset (next_v)
+ TYPE_LENGTH (el_type));
value_fetch_lazy (next_v);
if (!(value_available_contents_eq
(v, value_embedded_offset (v),
next_v, value_embedded_offset (next_v),
TYPE_LENGTH (el_type))))
break;
}
if (reps == 1)
fprintf_filtered (stream, "%d: ", i);
else
fprintf_filtered (stream, "%d..%d: ", i, i + reps - 1);
opts = *options;
opts.deref_ref = 1;
common_val_print (v, stream, 1, &opts, current_language);
things_printed++;
i += reps;
}
}
if (i < length)
fprintf_filtered (stream, "...");
fprintf_filtered (stream, "}");
return;
}
/* If it's type String, print it. */
if (TYPE_CODE (type) == TYPE_CODE_PTR
&& TYPE_TARGET_TYPE (type)
&& TYPE_TAG_NAME (TYPE_TARGET_TYPE (type))
&& strcmp (TYPE_TAG_NAME (TYPE_TARGET_TYPE (type)),
"java.lang.String") == 0
&& (options->format == 0 || options->format == 's')
&& address != 0
&& value_as_address (val) != 0)
{
struct type *char_type;
struct value *data_val;
CORE_ADDR data;
struct value *boffset_val;
unsigned long boffset;
struct value *count_val;
unsigned long count;
struct value *mark;
fputs_filtered (" ", stream);
mark = value_mark (); /* Remember start of new values. */
data_val = value_struct_elt (&val, NULL, "data", NULL, NULL);
data = value_as_address (data_val);
boffset_val = value_struct_elt (&val, NULL, "boffset", NULL, NULL);
boffset = value_as_address (boffset_val);
count_val = value_struct_elt (&val, NULL, "count", NULL, NULL);
count = value_as_address (count_val);
value_free_to_mark (mark); /* Release unnecessary values. */
char_type = builtin_java_type (gdbarch)->builtin_char;
val_print_string (char_type, NULL, data + boffset, count, stream,
options);
return;
}
opts = *options;
opts.deref_ref = 1;
common_val_print (val, stream, 0, &opts, current_language);
}
/* TYPE, VALADDR, ADDRESS, STREAM, RECURSE, and OPTIONS have the
same meanings as in cp_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. */
static void
java_print_value_fields (struct type *type, const gdb_byte *valaddr,
int offset,
CORE_ADDR address, struct ui_file *stream,
int recurse,
const struct value *val,
const struct value_print_options *options)
{
int i, len, n_baseclasses;
CHECK_TYPEDEF (type);
fprintf_filtered (stream, "{");
len = TYPE_NFIELDS (type);
n_baseclasses = TYPE_N_BASECLASSES (type);
if (n_baseclasses > 0)
{
int i, n_baseclasses = TYPE_N_BASECLASSES (type);
for (i = 0; i < n_baseclasses; i++)
{
int boffset;
struct type *baseclass = check_typedef (TYPE_BASECLASS (type, i));
const char *basename = TYPE_NAME (baseclass);
const gdb_byte *base_valaddr;
if (BASETYPE_VIA_VIRTUAL (type, i))
continue;
if (basename != NULL && strcmp (basename, "java.lang.Object") == 0)
continue;
boffset = 0;
if (options->prettyformat)
{
fprintf_filtered (stream, "\n");
print_spaces_filtered (2 * (recurse + 1), stream);
}
fputs_filtered ("<", stream);
/* Not sure what the best notation is in the case where there is no
baseclass name. */
fputs_filtered (basename ? basename : "", stream);
fputs_filtered ("> = ", stream);
base_valaddr = valaddr;
java_print_value_fields (baseclass, base_valaddr,
offset + boffset, address,
stream, recurse + 1, val, options);
fputs_filtered (", ", stream);
}
}
if (!len && n_baseclasses == 1)
fprintf_filtered (stream, "<No data fields>");
else
{
int fields_seen = 0;
for (i = n_baseclasses; i < len; i++)
{
/* If requested, skip printing of static fields. */
if (field_is_static (&TYPE_FIELD (type, i)))
{
const char *name = TYPE_FIELD_NAME (type, i);
if (!options->static_field_print)
continue;
if (name != NULL && strcmp (name, "class") == 0)
continue;
}
if (fields_seen)
fprintf_filtered (stream, ", ");
else if (n_baseclasses > 0)
{
if (options->prettyformat)
{
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 (options->prettyformat)
{
fprintf_filtered (stream, "\n");
print_spaces_filtered (2 + 2 * recurse, stream);
}
else
{
wrap_here (n_spaces (2 + 2 * recurse));
}
annotate_field_begin (TYPE_FIELD_TYPE (type, i));
if (field_is_static (&TYPE_FIELD (type, i)))
fputs_filtered ("static ", stream);
fprintf_symbol_filtered (stream, TYPE_FIELD_NAME (type, i),
language_cplus,
DMGL_PARAMS | DMGL_ANSI);
annotate_field_name_end ();
fputs_filtered (": ", stream);
annotate_field_value ();
if (!field_is_static (&TYPE_FIELD (type, i))
&& TYPE_FIELD_PACKED (type, i))
{
struct value *v;
/* Bitfields require special handling, especially due to byte
order problems. */
if (TYPE_FIELD_IGNORE (type, i))
{
fputs_filtered ("<optimized out or zero length>", stream);
}
else if (value_bits_synthetic_pointer (val,
TYPE_FIELD_BITPOS (type,
i),
TYPE_FIELD_BITSIZE (type,
i)))
{
fputs_filtered (_("<synthetic pointer>"), stream);
}
else if (!value_bits_valid (val, TYPE_FIELD_BITPOS (type, i),
TYPE_FIELD_BITSIZE (type, i)))
{
val_print_optimized_out (val, stream);
}
else
{
struct value_print_options opts;
v = value_field_bitfield (type, i, valaddr, offset, val);
opts = *options;
opts.deref_ref = 0;
common_val_print (v, stream, recurse + 1,
&opts, current_language);
}
}
else
{
if (TYPE_FIELD_IGNORE (type, i))
{
fputs_filtered ("<optimized out or zero length>", stream);
}
else if (field_is_static (&TYPE_FIELD (type, i)))
{
struct value_print_options opts;
struct value *v = value_static_field (type, i);
struct type *t = check_typedef (value_type (v));
if (TYPE_CODE (t) == TYPE_CODE_STRUCT)
v = value_addr (v);
opts = *options;
opts.deref_ref = 0;
common_val_print (v, stream, recurse + 1,
&opts, current_language);
}
else if (TYPE_FIELD_TYPE (type, i) == NULL)
fputs_filtered ("<unknown type>", stream);
else
{
struct value_print_options opts = *options;
opts.deref_ref = 0;
val_print (TYPE_FIELD_TYPE (type, i),
valaddr,
offset + TYPE_FIELD_BITPOS (type, i) / 8,
address, stream, recurse + 1, val, &opts,
current_language);
}
}
annotate_field_end ();
}
if (options->prettyformat)
{
fprintf_filtered (stream, "\n");
print_spaces_filtered (2 * recurse, stream);
}
}
fprintf_filtered (stream, "}");
}
/* See val_print for a description of the various parameters of this
function; they are identical. */
void
java_val_print (struct type *type, const gdb_byte *valaddr,
int embedded_offset, CORE_ADDR address,
struct ui_file *stream, int recurse,
const struct value *val,
const struct value_print_options *options)
{
struct gdbarch *gdbarch = get_type_arch (type);
struct type *target_type;
CORE_ADDR addr;
CHECK_TYPEDEF (type);
switch (TYPE_CODE (type))
{
case TYPE_CODE_PTR:
if (options->format && options->format != 's')
{
val_print_scalar_formatted (type, valaddr, embedded_offset,
val, options, 0, stream);
break;
}
addr = unpack_pointer (type, valaddr + embedded_offset);
if (addr == 0)
{
fputs_filtered ("null", stream);
return;
}
target_type = check_typedef (TYPE_TARGET_TYPE (type));
if (TYPE_CODE (target_type) == TYPE_CODE_FUNC)
{
/* Try to print what function it points to. */
print_address_demangle (options, gdbarch, addr, stream, demangle);
return;
}
if (options->addressprint && options->format != 's')
{
fputs_filtered ("@", stream);
print_longest (stream, 'x', 0, (ULONGEST) addr);
}
return;
case TYPE_CODE_CHAR:
case TYPE_CODE_INT:
/* Can't just call c_val_print because that prints bytes as C
chars. */
if (options->format || options->output_format)
{
struct value_print_options opts = *options;
opts.format = (options->format ? options->format
: options->output_format);
val_print_scalar_formatted (type, valaddr, embedded_offset,
val, &opts, 0, stream);
}
else if (TYPE_CODE (type) == TYPE_CODE_CHAR
|| (TYPE_CODE (type) == TYPE_CODE_INT
&& TYPE_LENGTH (type) == 2
&& strcmp (TYPE_NAME (type), "char") == 0))
LA_PRINT_CHAR ((int) unpack_long (type, valaddr + embedded_offset),
type, stream);
else
val_print_type_code_int (type, valaddr + embedded_offset, stream);
break;
case TYPE_CODE_STRUCT:
java_print_value_fields (type, valaddr, embedded_offset,
address, stream, recurse, val, options);
break;
default:
c_val_print (type, valaddr, embedded_offset, address, stream,
recurse, val, options);
break;
}
}