jv-valprint.c   [plain text]


/* Support for printing Java values for GDB, the GNU debugger.
   Copyright 1997, 1998, 1999, 2000 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., 59 Temple Place - Suite 330,
   Boston, MA 02111-1307, USA.  */

#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 */

static void java_print_value_fields (struct type * type, char *valaddr,
				     CORE_ADDR address,
				     struct ui_file *stream, int format,
				     int recurse,
				     enum val_prettyprint pretty);


int
java_value_print (struct value *val, struct ui_file *stream, int format,
		  enum val_prettyprint pretty)
{
  struct type *type;
  CORE_ADDR address;
  int i;
  char *name;

  type = VALUE_TYPE (val);
  address = VALUE_ADDRESS (val) + VALUE_OFFSET (val);

  if (is_object_type (type))
    {
      CORE_ADDR obj_addr;

      /* Get the run-time type, and cast the object into that */

      obj_addr = unpack_pointer (type, VALUE_CONTENTS (val));

      if (obj_addr != 0)
	{
	  type = type_from_class (java_class_from_object (val));
	  type = lookup_pointer_type (type);

	  val = value_at (type, address, NULL);
	}
    }

  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] == ']'))
    {
      char buf4[4];
      long length;
      unsigned int things_printed = 0;
      int reps;
      struct type *el_type = java_primitive_type_from_name (name, i - 2);

      i = 0;
      read_memory (address + JAVA_OBJECT_SIZE, buf4, 4);

      length = (long) extract_signed_integer (buf4, 4);
      fprintf_filtered (stream, "{length: %ld", length);

      if (el_type == NULL)
	{
	  CORE_ADDR element;
	  CORE_ADDR next_element = -1; /* dummy initial value */

	  address += JAVA_OBJECT_SIZE + 4;	/* Skip object header and length. */

	  while (i < length && things_printed < print_max)
	    {
	      char *buf;

	      buf = alloca (TARGET_PTR_BIT / 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 += TARGET_PTR_BIT / HOST_CHAR_BIT;
		  element = extract_address (buf, sizeof (buf));
		}

	      for (reps = 1; i + reps < length; reps++)
		{
		  read_memory (address, buf, sizeof (buf));
		  address += TARGET_PTR_BIT / HOST_CHAR_BIT;
		  next_element = extract_address (buf, sizeof (buf));
		  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", paddr_nz (element));

	      things_printed++;
	      i += reps;
	    }
	}
      else
	{
	  struct value *v = allocate_value (el_type);
	  struct value *next_v = allocate_value (el_type);

	  VALUE_ADDRESS (v) = address + JAVA_OBJECT_SIZE + 4;
	  VALUE_ADDRESS (next_v) = VALUE_ADDRESS (v);

	  while (i < length && things_printed < 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
		{
		  VALUE_LAZY (v) = 1;
		  VALUE_OFFSET (v) = 0;
		}

	      VALUE_OFFSET (next_v) = VALUE_OFFSET (v);

	      for (reps = 1; i + reps < length; reps++)
		{
		  VALUE_LAZY (next_v) = 1;
		  VALUE_OFFSET (next_v) += TYPE_LENGTH (el_type);
		  if (memcmp (VALUE_CONTENTS (v), VALUE_CONTENTS (next_v),
			      TYPE_LENGTH (el_type)) != 0)
		    break;
		}

	      if (reps == 1)
		fprintf_filtered (stream, "%d: ", i);
	      else
		fprintf_filtered (stream, "%d..%d: ", i, i + reps - 1);

	      val_print (VALUE_TYPE (v), VALUE_CONTENTS (v), 0, 0,
			 stream, format, 2, 1, pretty);

	      things_printed++;
	      i += reps;
	    }
	}

      if (i < length)
	fprintf_filtered (stream, "...");

      fprintf_filtered (stream, "}");

      return 0;
    }

  /* If it's type String, print it */

  if (TYPE_CODE (type) == TYPE_CODE_PTR
      && TYPE_TARGET_TYPE (type)
      && TYPE_NAME (TYPE_TARGET_TYPE (type))
      && strcmp (TYPE_NAME (TYPE_TARGET_TYPE (type)), "java.lang.String") == 0
      && (format == 0 || format == 's')
      && address != 0
      && value_as_address (val) != 0)
    {
      struct value *data_val;
      CORE_ADDR data;
      struct value *boffset_val;
      unsigned long boffset;
      struct value *count_val;
      unsigned long count;
      struct value *mark;

      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 */

      val_print_string (data + boffset, count, 2, stream);

      return 0;
    }

  return (val_print (type, VALUE_CONTENTS (val), 0, address,
		     stream, format, 1, 0, pretty));
}

/* TYPE, VALADDR, ADDRESS, STREAM, RECURSE, and PRETTY 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, char *valaddr, CORE_ADDR address,
			 struct ui_file *stream, int format, int recurse,
			 enum val_prettyprint pretty)
{
  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));
	  char *basename = TYPE_NAME (baseclass);
	  char *base_valaddr;

	  if (BASETYPE_VIA_VIRTUAL (type, i))
	    continue;

	  if (basename != NULL && strcmp (basename, "java.lang.Object") == 0)
	    continue;

	  boffset = 0;

	  if (pretty)
	    {
	      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, address + boffset,
				   stream, format, recurse + 1, pretty);
	  fputs_filtered (", ", stream);

	flush_it:
	  ;
	}

    }

  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++)
	{
	  /* If requested, skip printing of static fields.  */
	  if (TYPE_FIELD_STATIC (type, i))
	    {
	      char *name = TYPE_FIELD_NAME (type, i);
	      if (!static_field_print)
		continue;
	      if (name != NULL && strcmp (name, "class") == 0)
		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);
	      if (TYPE_FIELD_STATIC (type, i))
		fputs_filtered ("static ", 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
	    {
	      annotate_field_begin (TYPE_FIELD_TYPE (type, i));

	      if (TYPE_FIELD_STATIC (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 (!TYPE_FIELD_STATIC (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
		{
		  v = value_from_longest (TYPE_FIELD_TYPE (type, i),
				   unpack_field_as_long (type, valaddr, i));

		  val_print (TYPE_FIELD_TYPE (type, i), VALUE_CONTENTS (v), 0,
			     0, stream, format, 0, recurse + 1, pretty);
		}
	    }
	  else
	    {
	      if (TYPE_FIELD_IGNORE (type, i))
		{
		  fputs_filtered ("<optimized out or zero length>", stream);
		}
	      else if (TYPE_FIELD_STATIC (type, i))
		{
		  struct value *v = value_static_field (type, i);
		  if (v == NULL)
		    fputs_filtered ("<optimized out>", stream);
		  else
		    {
		      struct type *t = check_typedef (VALUE_TYPE (v));
		      if (TYPE_CODE (t) == TYPE_CODE_STRUCT)
			v = value_addr (v);
		      val_print (VALUE_TYPE (v),
				 VALUE_CONTENTS (v), 0, VALUE_ADDRESS (v),
				 stream, format, 0, recurse + 1, pretty);
		    }
		}
	      else if (TYPE_FIELD_TYPE (type, i) == NULL)
		fputs_filtered ("<unknown type>", stream);
	      else
		{
		  val_print (TYPE_FIELD_TYPE (type, i),
			     valaddr + TYPE_FIELD_BITPOS (type, i) / 8, 0,
			     address + TYPE_FIELD_BITPOS (type, i) / 8,
			     stream, format, 0, recurse + 1, pretty);
		}
	    }
	  annotate_field_end ();
	}

      if (pretty)
	{
	  fprintf_filtered (stream, "\n");
	  print_spaces_filtered (2 * recurse, stream);
	}
    }
  fprintf_filtered (stream, "}");
}

/* Print data of type TYPE located at VALADDR (within GDB), which came from
   the inferior at address ADDRESS, onto stdio stream STREAM according to
   FORMAT (a letter or 0 for natural format).  The data at VALADDR is in
   target byte order.

   If the data are a string pointer, returns the number of string characters
   printed.

   If DEREF_REF is nonzero, then dereference references, otherwise just print
   them like pointers.

   The PRETTY parameter controls prettyprinting.  */

int
java_val_print (struct type *type, char *valaddr, int embedded_offset,
		CORE_ADDR address, struct ui_file *stream, int format,
		int deref_ref, int recurse, enum val_prettyprint pretty)
{
  register unsigned int i = 0;	/* Number of characters printed */
  struct type *target_type;
  CORE_ADDR addr;

  CHECK_TYPEDEF (type);
  switch (TYPE_CODE (type))
    {
    case TYPE_CODE_PTR:
      if (format && format != 's')
	{
	  print_scalar_formatted (valaddr, type, format, 0, stream);
	  break;
	}
#if 0
      if (vtblprint && cp_is_vtbl_ptr_type (type))
	{
	  /* Print the unmangled name if desired.  */
	  /* Print vtable entry - we only get here if we ARE using
	     -fvtable_thunks.  (Otherwise, look under TYPE_CODE_STRUCT.) */
	  print_address_demangle (extract_address (valaddr, TYPE_LENGTH (type)),
				  stream, demangle);
	  break;
	}
#endif
      addr = unpack_pointer (type, valaddr);
      if (addr == 0)
	{
	  fputs_filtered ("null", stream);
	  return i;
	}
      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 (addr, stream, demangle);
	  /* Return value is irrelevant except for string pointers.  */
	  return (0);
	}

      if (addressprint && format != 's')
	{
	  fputs_filtered ("@", stream);
	  print_longest (stream, 'x', 0, (ULONGEST) addr);
	}

      return i;

    case TYPE_CODE_CHAR:
    case TYPE_CODE_INT:
      /* Can't just call c_val_print because that prints bytes as C
	 chars.  */
      format = format ? format : output_format;
      if (format)
	print_scalar_formatted (valaddr, type, format, 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), stream);
      else
	val_print_type_code_int (type, valaddr, stream);
      break;

    case TYPE_CODE_STRUCT:
      java_print_value_fields (type, valaddr, address, stream, format,
			       recurse, pretty);
      break;

    default:
      return c_val_print (type, valaddr, embedded_offset, address, stream,
			  format, deref_ref, recurse, pretty);
    }

  return 0;
}