binutils-gdb/gdb/jv-valprint.c

/* Support for printing Java values for GDB, the GNU debugger.

   Copyright (C) 1997-2016 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"
/* 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);
	  type = value_type (val);
	}
    }

  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 = ((gdb_byte *)
		     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_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;

  type = 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
		{
		  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;

  type = 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;
    }
}