2002-09-18 Michael Snyder <msnyder@redhat.com>

	* objc-lang.c: New file, support for Objective-C.
	Preliminary check-in, not yet integrated into gdb.
        * objc-lang.h: New file.
        * objc-exp.y:  New file.

1 files changed, 1905 insertions, 0 deletions

diff --git a/gdb/objc-lang.c b/gdb/objc-lang.c
new file mode 100644
index 0000000..594a0cb
--- /dev/null
+++ b/gdb/objc-lang.c
@@ -0,0 +1,1905 @@
+/* Objective C language support routines for GDB, the GNU debugger.
+   Copyright 1996 NeXT Software, 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 "expression.h"
+#include "parser-defs.h"
+#include "language.h"
+#include "objc-lang.h"
+#include "complaints.h"
+#include "value.h"
+#include "symfile.h"
+#include "objfiles.h"
+#include "string.h"		/* for strchr */
+#include "target.h"		/* for target_has_execution */
+#include "gdbcore.h"
+#include "gdbcmd.h"
+#include "frame.h"
+#include "gdb_regex.h"
+#include "regcache.h"
+
+#include <ctype.h>
+
+struct objc_object {
+  CORE_ADDR isa;
+};
+
+struct objc_class {
+  CORE_ADDR isa; 
+  CORE_ADDR super_class; 
+  CORE_ADDR name;               
+  long version;
+  long info;
+  long instance_size;
+  CORE_ADDR ivars;
+  CORE_ADDR methods;
+  CORE_ADDR cache;
+  CORE_ADDR protocols;
+};
+
+struct objc_super {
+  CORE_ADDR receiver;
+  CORE_ADDR class;
+};
+
+struct objc_method {
+  CORE_ADDR name;
+  CORE_ADDR types;
+  CORE_ADDR imp;
+};
+
+/* Complaints about ObjC classes, selectors, etc.  */
+
+static struct complaint noclass_lookup_complaint = 
+  {"no way to lookup Objective-C classes", 0, 0};
+
+static struct complaint nosel_lookup_complaint = 
+  {"no way to lookup Objective-C selectors", 0, 0};
+
+
+#if (!defined __GNUC__ || __GNUC__ < 2 || __GNUC_MINOR__ < (defined __cplusplus ? 6 : 4))
+#define __CHECK_FUNCTION ((__const char *) 0)
+#else
+#define __CHECK_FUNCTION __PRETTY_FUNCTION__
+#endif
+
+#define CHECK(expression) \
+  ((void) ((expression) ? 0 : gdb_check (#expression, __FILE__, __LINE__, \
+                                         __CHECK_FUNCTION)))
+
+#define CHECK_FATAL(expression) \
+  ((void) ((expression) ? 0 : gdb_check_fatal (#expression, __FILE__, \
+                              __LINE__, __CHECK_FUNCTION)))
+
+void 
+gdb_check (const char *str, const char *file, unsigned int line, 
+	   const char *func)
+{
+  error ("assertion failure on line %u of \"%s\" in function \"%s\": %s\n",
+	 line, file, func, str);
+}
+
+void 
+gdb_check_fatal (const char *str, const char *file, unsigned int line, 
+		 const char *func)
+{
+  internal_error (file, line, 
+		  "assertion failure in function \"%s\": %s\n", func, str);
+}
+
+/* Lookup a structure type named "struct NAME",
+   visible in lexical block BLOCK.  
+   If NOERR is nonzero, return zero if NAME is not suitably defined.  */
+
+struct symbol *
+lookup_struct_typedef (char *name, struct block *block, int noerr)
+{
+  register struct symbol *sym;
+
+  sym = lookup_symbol (name, block, STRUCT_NAMESPACE, 0, (struct symtab **) NULL);
+
+  if (sym == NULL)
+    {
+      if (noerr)
+	return 0;
+      else 
+	error ("No struct type named %s.", name);
+    }
+  if (TYPE_CODE (SYMBOL_TYPE (sym)) != TYPE_CODE_STRUCT)
+    {
+      if (noerr)
+	return 0;
+      else
+	error ("This context has class, union or enum %s, not a struct.", name);
+    }
+  return sym;
+}
+
+CORE_ADDR 
+lookup_objc_class (char *classname)
+{
+  struct value * function, *classval;
+
+  if (! target_has_execution)
+    {
+      /* can't call into inferior to lookup class */
+      return 0;
+    }
+
+  if (lookup_minimal_symbol("objc_lookUpClass", 0, 0))
+    function = find_function_in_inferior("objc_lookUpClass");
+  else if (lookup_minimal_symbol ("objc_lookup_class", 0, 0))
+    function = find_function_in_inferior("objc_lookup_class");
+  else
+    {
+      complain (&noclass_lookup_complaint, 0);
+      return 0;
+    }
+
+  classval = value_string (classname, strlen (classname) + 1);
+  classval = value_coerce_array (classval);
+  return (CORE_ADDR) value_as_long (call_function_by_hand (function, 
+							   1, &classval));
+}
+
+int
+lookup_child_selector (char *selname)
+{
+  struct value * function, *selstring;
+
+  if (! target_has_execution)
+    {
+      /* can't call into inferior to lookup selector */
+      return 0;
+    }
+
+  if (lookup_minimal_symbol("sel_getUid", 0, 0))
+    function = find_function_in_inferior("sel_getUid");
+  else if (lookup_minimal_symbol ("sel_get_any_uid", 0, 0))
+    function = find_function_in_inferior("sel_get_any_uid");
+  else
+    {
+      complain (&nosel_lookup_complaint, 0);
+      return 0;
+    }
+
+  selstring = value_coerce_array (value_string (selname, strlen (selname) + 1));
+  return value_as_long (call_function_by_hand (function, 1, &selstring));
+}
+
+struct value * 
+value_nsstring (char *ptr, int len)
+{
+  struct value *stringValue[3];
+  struct value *function, *nsstringValue;
+  struct symbol *sym;
+  struct type *type;
+
+  if (!target_has_execution)
+    return 0;		/* can't call into inferior to create NSString */
+
+  if (!(sym = lookup_struct_typedef("NSString", 0, 1)) &&
+      !(sym = lookup_struct_typedef("NXString", 0, 1)))
+    type = lookup_pointer_type(builtin_type_void);
+  else
+    type = lookup_pointer_type(SYMBOL_TYPE (sym));
+
+  stringValue[2] = value_string(ptr, len);
+  stringValue[2] = value_coerce_array(stringValue[2]);
+  /* _NSNewStringFromCString replaces "istr" after Lantern2A */
+  if (lookup_minimal_symbol("_NSNewStringFromCString", 0, 0))
+    {
+      function = find_function_in_inferior("_NSNewStringFromCString");
+      nsstringValue = call_function_by_hand(function, 1, &stringValue[2]);
+    }
+  else if (lookup_minimal_symbol("istr", 0, 0))
+    {
+      function = find_function_in_inferior("istr");
+      nsstringValue = call_function_by_hand(function, 1, &stringValue[2]);
+    }
+  else if (lookup_minimal_symbol("+[NSString stringWithCString:]", 0, 0))
+    {
+      function = find_function_in_inferior("+[NSString stringWithCString:]");
+      stringValue[0] = value_from_longest 
+	(builtin_type_long, lookup_objc_class ("NSString"));
+      stringValue[1] = value_from_longest 
+	(builtin_type_long, lookup_child_selector ("stringWithCString:"));
+      nsstringValue = call_function_by_hand(function, 3, &stringValue[0]);
+    }
+  else
+    error ("NSString: internal error -- no way to create new NSString");
+
+  VALUE_TYPE(nsstringValue) = type;
+  return nsstringValue;
+}
+
+/* Objective C name demangling */
+
+char *
+objc_demangle (const char *mangled)
+{
+  char *demangled, *cp;
+
+  if (mangled[0] == '_' &&
+     (mangled[1] == 'i' || mangled[1] == 'c') &&
+      mangled[2] == '_')
+    {
+      cp = demangled = xmalloc(strlen(mangled) + 2);
+
+      if (mangled[1] == 'i')
+	*cp++ = '-';		/* for instance method */
+      else
+	*cp++ = '+';		/* for class    method */
+
+      *cp++ = '[';		/* opening left brace  */
+      strcpy(cp, mangled+3);	/* tack on the rest of the mangled name */
+
+      while (*cp && *cp == '_')
+	cp++;			/* skip any initial underbars in class name */
+
+      if (!(cp = strchr(cp, '_')))	/* find first non-initial underbar */
+	{
+	  free(demangled);	/* not mangled name */
+	  return NULL;
+	}
+      if (cp[1] == '_') {	/* easy case: no category name     */
+	*cp++ = ' ';		/* replace two '_' with one ' '    */
+	strcpy(cp, mangled + (cp - demangled) + 2);
+      }
+      else {
+	*cp++ = '(';		/* less easy case: category name */
+	if (!(cp = strchr(cp, '_')))
+	  {
+	    free(demangled);	/* not mangled name */
+	    return NULL;
+	  }
+	*cp++ = ')';
+	*cp++ = ' ';		/* overwriting 1st char of method name... */
+	strcpy(cp, mangled + (cp - demangled));	/* get it back */
+      }
+
+      while (*cp && *cp == '_')
+	cp++;			/* skip any initial underbars in method name */
+
+      for (; *cp; cp++)
+	if (*cp == '_')
+	  *cp = ':';		/* replace remaining '_' with ':' */
+
+      *cp++ = ']';		/* closing right brace */
+      *cp++ = 0;		/* string terminator */
+      return demangled;
+    }
+  else
+    return NULL;	/* not an objc mangled name */
+}
+
+/* Print the character C on STREAM as part of the contents of a literal
+   string whose delimiter is QUOTER.  Note that that format for printing
+   characters and strings is language specific. */
+
+static void
+objc_emit_char (register int c, struct ui_file *stream, int quoter)
+{
+
+  c &= 0xFF;			/* Avoid sign bit follies */
+
+  if (PRINT_LITERAL_FORM (c))
+    {
+      if (c == '\\' || c == quoter)
+	{
+	  fputs_filtered ("\\", stream);
+	}
+      fprintf_filtered (stream, "%c", c);
+    }
+  else
+    {
+      switch (c)
+	{
+	case '\n':
+	  fputs_filtered ("\\n", stream);
+	  break;
+	case '\b':
+	  fputs_filtered ("\\b", stream);
+	  break;
+	case '\t':
+	  fputs_filtered ("\\t", stream);
+	  break;
+	case '\f':
+	  fputs_filtered ("\\f", stream);
+	  break;
+	case '\r':
+	  fputs_filtered ("\\r", stream);
+	  break;
+	case '\033':
+	  fputs_filtered ("\\e", stream);
+	  break;
+	case '\007':
+	  fputs_filtered ("\\a", stream);
+	  break;
+	default:
+	  fprintf_filtered (stream, "\\%.3o", (unsigned int) c);
+	  break;
+	}
+    }
+}
+
+static void
+objc_printchar (int c, struct ui_file *stream)
+{
+  fputs_filtered ("'", stream);
+  objc_emit_char (c, stream, '\'');
+  fputs_filtered ("'", stream);
+}
+
+/* Print the character string STRING, printing at most LENGTH characters.
+   Printing stops early if the number hits print_max; repeat counts
+   are printed as appropriate.  Print ellipses at the end if we
+   had to stop before printing LENGTH characters, or if FORCE_ELLIPSES.  */
+
+static void
+objc_printstr (struct ui_file *stream, char *string, unsigned int length, 
+	       int force_ellipses)
+{
+  register unsigned int i;
+  unsigned int things_printed = 0;
+  int in_quotes = 0;
+  int need_comma = 0;
+  extern int inspect_it;
+  extern int repeat_count_threshold;
+  extern int print_max;
+
+  /* If the string was not truncated due to `set print elements', and
+     the last byte of it is a null, we don't print that, in traditional C
+     style.  */
+  if ((!force_ellipses) && length > 0 && string[length-1] == '\0')
+    length--;
+
+  if (length == 0)
+    {
+      fputs_filtered ("\"\"", stream);
+      return;
+    }
+
+  for (i = 0; i < length && things_printed < print_max; ++i)
+    {
+      /* Position of the character we are examining
+	 to see whether it is repeated.  */
+      unsigned int rep1;
+      /* Number of repetitions we have detected so far.  */
+      unsigned int reps;
+
+      QUIT;
+
+      if (need_comma)
+	{
+	  fputs_filtered (", ", stream);
+	  need_comma = 0;
+	}
+
+      rep1 = i + 1;
+      reps = 1;
+      while (rep1 < length && string[rep1] == string[i])
+	{
+	  ++rep1;
+	  ++reps;
+	}
+
+      if (reps > repeat_count_threshold)
+	{
+	  if (in_quotes)
+	    {
+	      if (inspect_it)
+		fputs_filtered ("\\\", ", stream);
+	      else
+		fputs_filtered ("\", ", stream);
+	      in_quotes = 0;
+	    }
+	  objc_printchar (string[i], stream);
+	  fprintf_filtered (stream, " <repeats %u times>", reps);
+	  i = rep1 - 1;
+	  things_printed += repeat_count_threshold;
+	  need_comma = 1;
+	}
+      else
+	{
+	  if (!in_quotes)
+	    {
+	      if (inspect_it)
+		fputs_filtered ("\\\"", stream);
+	      else
+		fputs_filtered ("\"", stream);
+	      in_quotes = 1;
+	    }
+	  objc_emit_char (string[i], stream, '"');
+	  ++things_printed;
+	}
+    }
+
+  /* Terminate the quotes if necessary.  */
+  if (in_quotes)
+    {
+      if (inspect_it)
+	fputs_filtered ("\\\"", stream);
+      else
+	fputs_filtered ("\"", stream);
+    }
+
+  if (force_ellipses || i < length)
+    fputs_filtered ("...", stream);
+}
+
+/* Create a fundamental C type using default reasonable for the current
+   target machine.
+
+   Some object/debugging file formats (DWARF version 1, COFF, etc) do not
+   define fundamental types such as "int" or "double".  Others (stabs or
+   DWARF version 2, etc) do define fundamental types.  For the formats which
+   don't provide fundamental types, gdb can create such types using this
+   function.
+
+   FIXME:  Some compilers distinguish explicitly signed integral types
+   (signed short, signed int, signed long) from "regular" integral types
+   (short, int, long) in the debugging information.  There is some dis-
+   agreement as to how useful this feature is.  In particular, gcc does
+   not support this.  Also, only some debugging formats allow the
+   distinction to be passed on to a debugger.  For now, we always just
+   use "short", "int", or "long" as the type name, for both the implicit
+   and explicitly signed types.  This also makes life easier for the
+   gdb test suite since we don't have to account for the differences
+   in output depending upon what the compiler and debugging format
+   support.  We will probably have to re-examine the issue when gdb
+   starts taking it's fundamental type information directly from the
+   debugging information supplied by the compiler.  fnf@cygnus.com */
+
+static struct type *
+objc_create_fundamental_type (struct objfile *objfile, int typeid)
+{
+  register struct type *type = NULL;
+
+  switch (typeid)
+    {
+      default:
+	/* FIXME:  For now, if we are asked to produce a type not in this
+	   language, create the equivalent of a C integer type with the
+	   name "<?type?>".  When all the dust settles from the type
+	   reconstruction work, this should probably become an error. */
+	type = init_type (TYPE_CODE_INT,
+			  TARGET_INT_BIT / TARGET_CHAR_BIT,
+			  0, "<?type?>", objfile);
+        warning ("internal error: no C/C++ fundamental type %d", typeid);
+	break;
+      case FT_VOID:
+	type = init_type (TYPE_CODE_VOID,
+			  TARGET_CHAR_BIT / TARGET_CHAR_BIT,
+			  0, "void", objfile);
+	break;
+      case FT_CHAR:
+	type = init_type (TYPE_CODE_INT,
+			  TARGET_CHAR_BIT / TARGET_CHAR_BIT,
+			  0, "char", objfile);
+	break;
+      case FT_SIGNED_CHAR:
+	type = init_type (TYPE_CODE_INT,
+			  TARGET_CHAR_BIT / TARGET_CHAR_BIT,
+			  0, "signed char", objfile);
+	break;
+      case FT_UNSIGNED_CHAR:
+	type = init_type (TYPE_CODE_INT,
+			  TARGET_CHAR_BIT / TARGET_CHAR_BIT,
+			  TYPE_FLAG_UNSIGNED, "unsigned char", objfile);
+	break;
+      case FT_SHORT:
+	type = init_type (TYPE_CODE_INT,
+			  TARGET_SHORT_BIT / TARGET_CHAR_BIT,
+			  0, "short", objfile);
+	break;
+      case FT_SIGNED_SHORT:
+	type = init_type (TYPE_CODE_INT,
+			  TARGET_SHORT_BIT / TARGET_CHAR_BIT,
+			  0, "short", objfile);	/* FIXME-fnf */
+	break;
+      case FT_UNSIGNED_SHORT:
+	type = init_type (TYPE_CODE_INT,
+			  TARGET_SHORT_BIT / TARGET_CHAR_BIT,
+			  TYPE_FLAG_UNSIGNED, "unsigned short", objfile);
+	break;
+      case FT_INTEGER:
+	type = init_type (TYPE_CODE_INT,
+			  TARGET_INT_BIT / TARGET_CHAR_BIT,
+			  0, "int", objfile);
+	break;
+      case FT_SIGNED_INTEGER:
+	type = init_type (TYPE_CODE_INT,
+			  TARGET_INT_BIT / TARGET_CHAR_BIT,
+			  0, "int", objfile); /* FIXME -fnf */
+	break;
+      case FT_UNSIGNED_INTEGER:
+	type = init_type (TYPE_CODE_INT,
+			  TARGET_INT_BIT / TARGET_CHAR_BIT,
+			  TYPE_FLAG_UNSIGNED, "unsigned int", objfile);
+	break;
+      case FT_LONG:
+	type = init_type (TYPE_CODE_INT,
+			  TARGET_LONG_BIT / TARGET_CHAR_BIT,
+			  0, "long", objfile);
+	break;
+      case FT_SIGNED_LONG:
+	type = init_type (TYPE_CODE_INT,
+			  TARGET_LONG_BIT / TARGET_CHAR_BIT,
+			  0, "long", objfile); /* FIXME -fnf */
+	break;
+      case FT_UNSIGNED_LONG:
+	type = init_type (TYPE_CODE_INT,
+			  TARGET_LONG_BIT / TARGET_CHAR_BIT,
+			  TYPE_FLAG_UNSIGNED, "unsigned long", objfile);
+	break;
+      case FT_LONG_LONG:
+	type = init_type (TYPE_CODE_INT,
+			  TARGET_LONG_LONG_BIT / TARGET_CHAR_BIT,
+			  0, "long long", objfile);
+	break;
+      case FT_SIGNED_LONG_LONG:
+	type = init_type (TYPE_CODE_INT,
+			  TARGET_LONG_LONG_BIT / TARGET_CHAR_BIT,
+			  0, "signed long long", objfile);
+	break;
+      case FT_UNSIGNED_LONG_LONG:
+	type = init_type (TYPE_CODE_INT,
+			  TARGET_LONG_LONG_BIT / TARGET_CHAR_BIT,
+			  TYPE_FLAG_UNSIGNED, "unsigned long long", objfile);
+	break;
+      case FT_FLOAT:
+	type = init_type (TYPE_CODE_FLT,
+			  TARGET_FLOAT_BIT / TARGET_CHAR_BIT,
+			  0, "float", objfile);
+	break;
+      case FT_DBL_PREC_FLOAT:
+	type = init_type (TYPE_CODE_FLT,
+			  TARGET_DOUBLE_BIT / TARGET_CHAR_BIT,
+			  0, "double", objfile);
+	break;
+      case FT_EXT_PREC_FLOAT:
+	type = init_type (TYPE_CODE_FLT,
+			  TARGET_LONG_DOUBLE_BIT / TARGET_CHAR_BIT,
+			  0, "long double", objfile);
+	break;
+      }
+  return (type);
+}
+
+
+/* Table mapping opcodes into strings for printing operators
+   and precedences of the operators.  */
+
+static const struct op_print objc_op_print_tab[] =
+  {
+    {",",  BINOP_COMMA, PREC_COMMA, 0},
+    {"=",  BINOP_ASSIGN, PREC_ASSIGN, 1},
+    {"||", BINOP_LOGICAL_OR, PREC_LOGICAL_OR, 0},
+    {"&&", BINOP_LOGICAL_AND, PREC_LOGICAL_AND, 0},
+    {"|",  BINOP_BITWISE_IOR, PREC_BITWISE_IOR, 0},
+    {"^",  BINOP_BITWISE_XOR, PREC_BITWISE_XOR, 0},
+    {"&",  BINOP_BITWISE_AND, PREC_BITWISE_AND, 0},
+    {"==", BINOP_EQUAL, PREC_EQUAL, 0},
+    {"!=", BINOP_NOTEQUAL, PREC_EQUAL, 0},
+    {"<=", BINOP_LEQ, PREC_ORDER, 0},
+    {">=", BINOP_GEQ, PREC_ORDER, 0},
+    {">",  BINOP_GTR, PREC_ORDER, 0},
+    {"<",  BINOP_LESS, PREC_ORDER, 0},
+    {">>", BINOP_RSH, PREC_SHIFT, 0},
+    {"<<", BINOP_LSH, PREC_SHIFT, 0},
+    {"+",  BINOP_ADD, PREC_ADD, 0},
+    {"-",  BINOP_SUB, PREC_ADD, 0},
+    {"*",  BINOP_MUL, PREC_MUL, 0},
+    {"/",  BINOP_DIV, PREC_MUL, 0},
+    {"%",  BINOP_REM, PREC_MUL, 0},
+    {"@",  BINOP_REPEAT, PREC_REPEAT, 0},
+    {"-",  UNOP_NEG, PREC_PREFIX, 0},
+    {"!",  UNOP_LOGICAL_NOT, PREC_PREFIX, 0},
+    {"~",  UNOP_COMPLEMENT, PREC_PREFIX, 0},
+    {"*",  UNOP_IND, PREC_PREFIX, 0},
+    {"&",  UNOP_ADDR, PREC_PREFIX, 0},
+    {"sizeof ", UNOP_SIZEOF, PREC_PREFIX, 0},
+    {"++", UNOP_PREINCREMENT, PREC_PREFIX, 0},
+    {"--", UNOP_PREDECREMENT, PREC_PREFIX, 0},
+    {NULL, 0, 0, 0}
+};
+
+struct type ** const (objc_builtin_types[]) = 
+{
+  &builtin_type_int,
+  &builtin_type_long,
+  &builtin_type_short,
+  &builtin_type_char,
+  &builtin_type_float,
+  &builtin_type_double,
+  &builtin_type_void,
+  &builtin_type_long_long,
+  &builtin_type_signed_char,
+  &builtin_type_unsigned_char,
+  &builtin_type_unsigned_short,
+  &builtin_type_unsigned_int,
+  &builtin_type_unsigned_long,
+  &builtin_type_unsigned_long_long,
+  &builtin_type_long_double,
+  &builtin_type_complex,
+  &builtin_type_double_complex,
+  0
+};
+
+const struct language_defn objc_language_defn = {
+  "objective-c",				/* Language name */
+  language_objc,
+  objc_builtin_types,
+  range_check_off,
+  type_check_off,
+  case_sensitive_on,
+  objc_parse,
+  objc_error,
+  evaluate_subexp_standard,
+  objc_printchar,		/* Print a character constant */
+  objc_printstr,		/* Function to print string constant */
+  objc_emit_char,
+  objc_create_fundamental_type,	/* Create fundamental type in this language */
+  c_print_type,			/* Print a type using appropriate syntax */
+  c_val_print,			/* Print a value using appropriate syntax */
+  c_value_print,		/* Print a top-level value */
+  {"",     "",    "",  ""},	/* Binary format info */
+  {"0%lo",  "0",   "o", ""},	/* Octal format info */
+  {"%ld",   "",    "d", ""},	/* Decimal format info */
+  {"0x%lx", "0x",  "x", ""},	/* Hex format info */
+  objc_op_print_tab,		/* expression operators for printing */
+  1,				/* c-style arrays */
+  0,				/* String lower bound */
+  &builtin_type_char,		/* Type of string elements */
+  LANG_MAGIC
+};
+
+/*
+ * ObjC:
+ * Following functions help construct Objective C message calls 
+ */
+
+struct selname		/* for parsing Objective C */
+  {
+    struct selname *next;
+    char *msglist_sel;
+    int msglist_len;
+  };
+
+static int msglist_len;
+static struct selname *selname_chain;
+static char *msglist_sel;
+
+void
+start_msglist(void)
+{
+  register struct selname *new = 
+    (struct selname *) xmalloc (sizeof (struct selname));
+
+  new->next = selname_chain;
+  new->msglist_len = msglist_len;
+  new->msglist_sel = msglist_sel;
+  msglist_len = 0;
+  msglist_sel = (char *)xmalloc(1);
+  *msglist_sel = 0;
+  selname_chain = new;
+}
+
+void
+add_msglist(struct stoken *str, int addcolon)
+{
+  char *s, *p;
+  int len, plen;
+
+  if (str == 0) {		/* unnamed arg, or... */
+    if (addcolon == 0) {	/* variable number of args */
+      msglist_len++;
+      return;
+    }
+    p = "";
+    plen = 0;
+  } else {
+    p = str->ptr;
+    plen = str->length;
+  }
+  len = plen + strlen(msglist_sel) + 2;
+  s = (char *)xmalloc(len);
+  strcpy(s, msglist_sel);
+  strncat(s, p, plen);
+  free(msglist_sel);
+  msglist_sel = s;
+  if (addcolon) {
+    s[len-2] = ':';
+    s[len-1] = 0;
+    msglist_len++;
+  } else
+    s[len-2] = '\0';
+}
+
+int
+end_msglist(void)
+{
+  register int val = msglist_len;
+  register struct selname *sel = selname_chain;
+  register char *p = msglist_sel;
+  int selid;
+
+  selname_chain = sel->next;
+  msglist_len = sel->msglist_len;
+  msglist_sel = sel->msglist_sel;
+  selid = lookup_child_selector(p);
+  if (!selid)
+    error("Can't find selector \"%s\"", p);
+  write_exp_elt_longcst (selid);
+  free(p);
+  write_exp_elt_longcst (val);/* Number of args */
+  free(sel);
+
+  return val;
+}
+
+/*
+ * Function: specialcmp (char *a, char *b)
+ *
+ * Special strcmp: treats ']' and ' ' as end-of-string.
+ * Used for qsorting lists of objc methods (either by class or selector) 
+ */
+
+int specialcmp(char *a, char *b)
+{
+  while (*a && *a != ' ' && *a != ']' && *b && *b != ' ' && *b != ']')
+    {
+      if (*a != *b)
+	return *a - *b;
+      a++, b++;
+    }
+  if (*a && *a != ' ' && *a != ']')
+    return  1;		/* a is longer therefore greater */
+  if (*b && *b != ' ' && *b != ']')
+    return -1;		/* a is shorter therefore lesser */
+  return    0;		/* a and b are identical */
+}
+
+/*
+ * Function: compare_selectors (void *, void *)
+ *
+ * Comparison function for use with qsort.  Arguments are symbols or msymbols
+ * Compares selector part of objc method name alphabetically.
+ */
+
+static int
+compare_selectors (a, b)
+     void *a;
+     void *b;
+{
+  char *aname, *bname;
+
+  if ((aname = SYMBOL_SOURCE_NAME (*(struct symbol **) a)) == NULL ||
+      (bname = SYMBOL_SOURCE_NAME (*(struct symbol **) b)) == NULL)
+    error ("internal: compare_selectors(1)");
+
+  if ((aname = strchr(aname, ' ')) == NULL ||
+      (bname = strchr(bname, ' ')) == NULL)
+    error ("internal: compare_selectors(2)");
+
+  return specialcmp (aname+1, bname+1);
+}
+
+/*
+ * Function: selectors_info (regexp, from_tty)
+ *
+ * Implements the "Info selectors" command.  Takes an optional regexp arg.
+ * Lists all objective c selectors that match the regexp.  Works by 
+ * grepping thru all symbols for objective c methods.  Output list is 
+ * sorted and uniqued. 
+ */
+
+static void
+selectors_info (char *regexp, int from_tty)
+{
+  struct objfile	*objfile;
+  struct minimal_symbol *msymbol;
+  char                  *name;
+  char                  *val;
+  int                    matches = 0;
+  int                    maxlen  = 0;
+  int                    ix;
+  char                   myregexp[2048];
+  char                   asel[256];
+  struct symbol        **sym_arr;
+  int                    plusminus = 0;
+
+  if (regexp == NULL)
+    strcpy(myregexp, ".*]");	/* null input, match all objc methods */
+  else
+    {
+      if (*regexp == '+' || *regexp == '-')	/* if regexp starts with +/- */
+	{ 	   /* user wants only class methods or only instance methods */
+	  plusminus = *regexp++;
+	  while (*regexp == ' ' || *regexp == '\t')
+	    regexp++;
+	}
+      if (*regexp == '\0')
+	strcpy(myregexp, ".*]");
+      else
+	{
+	  strcpy(myregexp, regexp);
+	  if (myregexp[strlen(myregexp) - 1] == '$') /* end of selector */
+	    myregexp[strlen(myregexp) - 1] = ']';    /* end of method name */
+	  else
+	    strcat(myregexp, ".*]");
+	}
+    }
+
+  if (regexp != NULL)
+    if (0 != (val = re_comp (myregexp)))
+      error ("Invalid regexp (%s): %s", val, regexp);
+
+  /* first time thru is JUST to get max length and count */
+  ALL_MSYMBOLS (objfile, msymbol)
+    {
+      QUIT;
+      if ((name = SYMBOL_DEMANGLED_NAME (msymbol)) == NULL)
+	name = SYMBOL_NAME (msymbol);
+      if (name &&
+	 (name[0] == '-' || name[0] == '+') &&
+	  name[1] == '[')		/* got a method name */
+	{
+	  if (plusminus && name[0] != plusminus)
+	    continue;			/* filter for class/instance methods */
+	  name = (char *) strchr(name+2, ' ');	/* find selector part */
+	  if (regexp == NULL || re_exec(++name) != 0)
+	    { 
+	      char *mystart = name;
+	      char *myend   = (char *) strchr(mystart, ']');
+	      
+	      if (myend && (myend - mystart > maxlen))
+		maxlen = myend - mystart;	/* get longest selector */
+	      matches++;
+	    }
+	}
+    }
+  if (matches)
+    {
+      printf_filtered ("Selectors matching \"%s\":\n\n", 
+		       regexp ? regexp : "*");
+
+      sym_arr = alloca (matches * sizeof (struct symbol *));
+      matches = 0;
+      ALL_MSYMBOLS (objfile, msymbol)
+	{
+	  QUIT;
+	  if ((name = SYMBOL_DEMANGLED_NAME (msymbol)) == NULL)
+	    name = SYMBOL_NAME (msymbol);
+	  if (name &&
+	     (name[0] == '-' || name[0] == '+') &&
+	      name[1] == '[')		/* got a method name */
+	    {
+	      if (plusminus && name[0] != plusminus)
+		continue;		/* filter for class/instance methods */
+	      name = (char *) strchr(name+2, ' ');     /* find selector part */
+	      if (regexp == NULL || re_exec(++name) != 0)
+		sym_arr[matches++] = (struct symbol *) msymbol;
+	    }
+	}
+
+      qsort (sym_arr, matches, sizeof (struct minimal_symbol *), 
+	     compare_selectors);
+      asel[0] = 0;		/* to prevent compare on first iteration */
+      for (ix = 0; ix < matches; ix++)	/* now do the output */
+	{
+	  char *p = asel;
+
+	  QUIT;
+	  if ((name = SYMBOL_DEMANGLED_NAME (sym_arr[ix])) == NULL)
+	    name = SYMBOL_NAME (sym_arr[ix]);
+	  name = strchr (name, ' ') + 1;
+	  if (p[0] && specialcmp(name, p) == 0)
+	    continue;		/* seen this one already (not unique) */
+
+	  while (*name && *name != ']')		/* copy selector part */
+	    *p++ = *name++;
+	  *p++ = '\0';
+	  puts_filtered_tabular(asel, maxlen + 1, 0);	/* print in columns */
+	}
+      begin_line();
+    }
+  else
+    printf_filtered ("No selectors matching \"%s\"\n", regexp ? regexp : "*");
+}
+
+/*
+ * Function: compare_classes (void *, void *)
+ *
+ * Comparison function for use with qsort.  Arguments are symbols or msymbols
+ * Compares class part of objc method name alphabetically.
+ */
+
+static int
+compare_classes (a, b)
+     void *a;
+     void *b;
+{
+  char *aname, *bname;
+
+  if ((aname = SYMBOL_SOURCE_NAME (*(struct symbol **) a)) == NULL ||
+      (bname = SYMBOL_SOURCE_NAME (*(struct symbol **) b)) == NULL)
+    error ("internal: compare_classes(1)");
+
+  return specialcmp (aname+1, bname+1);
+}
+
+/*
+ * Function: classes_info(regexp, from_tty)
+ *
+ * Implements the "info classes" command for objective c classes.
+ * Lists all objective c classes that match the optional regexp.
+ * Works by grepping thru the list of objective c methods.
+ * List will be sorted and uniqued (since one class may have many methods).
+ * BUGS: will not list a class that has no methods.
+ */
+
+static void
+classes_info (char *regexp, int from_tty)
+{
+  struct objfile	*objfile;
+  struct minimal_symbol *msymbol;
+  char                  *name;
+  char                  *val;
+  int                    matches = 0;
+  int                    maxlen  = 0;
+  int                    ix;
+  char                   myregexp[2048];
+  char                   aclass[256];
+  struct symbol        **sym_arr;
+
+  if (regexp == NULL)
+    strcpy(myregexp, ".* ");	/* null input: match all objc classes */
+  else
+    {
+      strcpy(myregexp, regexp);
+      if (myregexp[strlen(myregexp) - 1] == '$')
+	/* in the method name, the end of the class name is marked by ' ' */
+	myregexp[strlen(myregexp) - 1] = ' ';
+      else
+	strcat(myregexp, ".* ");
+    }
+
+  if (regexp != NULL)
+    if (0 != (val = re_comp (myregexp)))
+      error ("Invalid regexp (%s): %s", val, regexp);
+
+  /* first time thru is JUST to get max length and count */
+  ALL_MSYMBOLS (objfile, msymbol)
+    {
+      QUIT;
+      if ((name = SYMBOL_DEMANGLED_NAME (msymbol)) == NULL)
+	name = SYMBOL_NAME (msymbol);
+      if (name &&
+	 (name[0] == '-' || name[0] == '+') &&
+	  name[1] == '[')				/* got a method name */
+	if (regexp == NULL || re_exec(name+2) != 0)
+	  { 
+	    char *mystart = name + 2;	/* compute length of classname part */
+	    char *myend   = (char *) strchr(mystart, ' ');
+	    
+	    if (myend && (myend - mystart > maxlen))
+	      maxlen = myend - mystart;
+	    matches++;
+	  }
+    }
+  if (matches)
+    {
+      printf_filtered ("Classes matching \"%s\":\n\n", 
+		       regexp ? regexp : "*");
+      sym_arr = alloca (matches * sizeof (struct symbol *));
+      matches = 0;
+      ALL_MSYMBOLS (objfile, msymbol)
+	{
+	  QUIT;
+	  if ((name = SYMBOL_DEMANGLED_NAME (msymbol)) == NULL)
+	    name = SYMBOL_NAME (msymbol);
+	  if (name &&
+	     (name[0] == '-' || name[0] == '+') &&
+	      name[1] == '[')				/* got a method name */
+	    if (regexp == NULL || re_exec(name+2) != 0)
+		sym_arr[matches++] = (struct symbol *) msymbol;
+	}
+
+      qsort (sym_arr, matches, sizeof (struct minimal_symbol *), 
+	     compare_classes);
+      aclass[0] = 0;		/* to prevent compare on first iteration */
+      for (ix = 0; ix < matches; ix++)	/* now do the output */
+	{
+	  char *p = aclass;
+
+	  QUIT;
+	  if ((name = SYMBOL_DEMANGLED_NAME (sym_arr[ix])) == NULL)
+	    name = SYMBOL_NAME (sym_arr[ix]);
+	  name += 2;
+	  if (p[0] && specialcmp(name, p) == 0)
+	    continue;	/* seen this one already (not unique) */
+
+	  while (*name && *name != ' ')	/* copy class part of method name */
+	    *p++ = *name++;
+	  *p++ = '\0';
+	  puts_filtered_tabular(aclass, maxlen + 1, 0);	/* print in columns */
+	}
+      begin_line();
+    }
+  else
+    printf_filtered ("No classes matching \"%s\"\n", regexp ? regexp : "*");
+}
+
+/* 
+ * Function: find_imps (char *selector, struct symbol **sym_arr)
+ *
+ * Input:  a string representing a selector
+ *         a pointer to an array of symbol pointers
+ *         possibly a pointer to a symbol found by the caller.
+ *
+ * Output: number of methods that implement that selector.
+ * Side effects: The array of symbol pointers is filled with matching syms.
+ *
+ * By analogy with function "find_methods" (symtab.c), builds a list of
+ * symbols matching the ambiguous input, so that "decode_line_2" (symtab.c)
+ * can list them and ask the user to choose one or more.  In this case the
+ * matches are objective c methods ("implementations") matching an objective
+ * c selector.
+ *
+ * Note that it is possible for a normal (c-style) function to have the
+ * same name as an objective c selector.  To prevent the selector from
+ * eclipsing the function, we allow the caller (decode_line_1) to search
+ * for such a function first, and if it finds one, pass it in to us.  We
+ * will then integrate it into the list.  We also search for one here, 
+ * among the minsyms.
+ *
+ * NOTE: if NUM_DEBUGGABLE is non-zero, the sym_arr will be 
+ *       divided into two parts: debuggable (struct symbol) syms, 
+ *       and non_debuggable (struct minimal_symbol) syms.  
+ *       The debuggable ones will come first, before NUM_DEBUGGABLE
+ *       (which will thus be the index of the first non-debuggable one).
+ */
+
+/*
+ * Function: total_number_of_imps (char *selector);
+ *
+ * Input:  a string representing a selector 
+ * Output: number of methods that implement that selector.
+ *
+ * By analogy with function "total_number_of_methods", this allows 
+ * decode_line_1 (symtab.c) to detect if there are objective c methods
+ * matching the input, and to allocate an array of pointers to them 
+ * which can be manipulated by "decode_line_2" (also in symtab.c)
+ */
+
+char * 
+parse_selector (char *method, char **selector)
+{
+  char *s1 = NULL;
+  char *s2 = NULL;
+  int found_quote = 0;
+
+  char *nselector = NULL;
+
+  CHECK (selector != NULL);
+
+  s1 = method;
+
+  while (isspace (*s1))
+    s1++;
+  if (*s1 == '\'') 
+    {
+      found_quote = 1;
+      s1++;
+    }
+  while (isspace (*s1))
+    s1++;
+   
+  nselector = s1;
+  s2 = s1;
+
+  for (;;) {
+    if (isalnum (*s2) || (*s2 == '_') || (*s2 == ':'))
+      *s1++ = *s2;
+    else if (isspace (*s2))
+      ;
+    else if ((*s2 == '\0') || (*s2 == '\''))
+      break;
+    else
+      return NULL;
+    s2++;
+  }
+  *s1++ = '\0';
+
+  while (isspace (*s2))
+    s2++;
+  if (found_quote)
+    {
+      if (*s2 == '\'') 
+	s2++;
+      while (isspace (*s2))
+	s2++;
+    }
+
+  if (selector != NULL)
+    *selector = nselector;
+
+  return s2;
+}
+
+char * 
+parse_method (char *method, char *type, char **class, char **category, 
+	      char **selector)
+{
+  char *s1 = NULL;
+  char *s2 = NULL;
+  int found_quote = 0;
+
+  char ntype = '\0';
+  char *nclass = NULL;
+  char *ncategory = NULL;
+  char *nselector = NULL;
+
+  CHECK (type != NULL);
+  CHECK (class != NULL);
+  CHECK (category != NULL);
+  CHECK (selector != NULL);
+  
+  s1 = method;
+
+  while (isspace (*s1))
+    s1++;
+  if (*s1 == '\'') 
+    {
+      found_quote = 1;
+      s1++;
+    }
+  while (isspace (*s1))
+    s1++;
+  
+  if ((s1[0] == '+') || (s1[0] == '-'))
+    ntype = *s1++;
+
+  while (isspace (*s1))
+    s1++;
+
+  if (*s1 != '[')
+    return NULL;
+  s1++;
+
+  nclass = s1;
+  while (isalnum (*s1) || (*s1 == '_'))
+    s1++;
+  
+  s2 = s1;
+  while (isspace (*s2))
+    s2++;
+  
+  if (*s2 == '(')
+    {
+      s2++;
+      while (isspace (*s2))
+	s2++;
+      ncategory = s2;
+      while (isalnum (*s2) || (*s2 == '_'))
+	s2++;
+      *s2++ = '\0';
+    }
+
+  /* truncate the class name now that we're not using the open paren */
+  *s1++ = '\0';
+
+  nselector = s2;
+  s1 = s2;
+
+  for (;;) {
+    if (isalnum (*s2) || (*s2 == '_') || (*s2 == ':'))
+      *s1++ = *s2;
+    else if (isspace (*s2))
+      ;
+    else if (*s2 == ']')
+      break;
+    else
+      return NULL;
+    s2++;
+  }
+  *s1++ = '\0';
+  s2++;
+
+  while (isspace (*s2))
+    s2++;
+  if (found_quote)
+    {
+      if (*s2 != '\'') 
+	return NULL;
+      s2++;
+      while (isspace (*s2))
+	s2++;
+    }
+
+  if (type != NULL)
+    *type = ntype;
+  if (class != NULL)
+    *class = nclass;
+  if (category != NULL)
+    *category = ncategory;
+  if (selector != NULL)
+    *selector = nselector;
+
+  return s2;
+}
+
+void
+find_methods (struct symtab *symtab, 
+	      char type, const char *class, const char *category, 
+	      const char *selector,
+	      struct symbol **syms, unsigned int *nsym, unsigned int *ndebug)
+{
+  struct objfile *objfile = NULL;
+  struct minimal_symbol *msymbol = NULL;
+  struct block *block = NULL;
+  struct symbol *sym = NULL;
+
+  char *symname = NULL;
+
+  char ntype = '\0';
+  char *nclass = NULL;
+  char *ncategory = NULL;
+  char *nselector = NULL;
+
+  unsigned int csym = 0;
+  unsigned int cdebug = 0;
+
+  static char *tmp = NULL;
+  static unsigned int tmplen = 0;
+
+  CHECK (nsym != NULL);
+  CHECK (ndebug != NULL);
+
+  if (symtab)
+    block = BLOCKVECTOR_BLOCK (BLOCKVECTOR (symtab), STATIC_BLOCK);
+
+  ALL_MSYMBOLS (objfile, msymbol)
+    {
+      QUIT;
+
+      if ((msymbol->type != mst_text) && (msymbol->type != mst_file_text))
+	/* not a function or method */
+	continue;
+
+      if (symtab)
+	if ((SYMBOL_VALUE_ADDRESS (msymbol) <  block->startaddr) ||
+	    (SYMBOL_VALUE_ADDRESS (msymbol) >= block->endaddr))
+	  /* not in the specified symtab */
+	  continue;
+
+      symname = SYMBOL_DEMANGLED_NAME (msymbol);
+      if (symname == NULL)
+	symname = SYMBOL_NAME (msymbol);
+      if (symname == NULL)
+	continue;
+
+      if ((symname[0] != '-' && symname[0] != '+') || (symname[1] != '['))
+	/* not a method name */
+	continue;
+      
+      while ((strlen (symname) + 1) >= tmplen)
+	{
+	  tmplen = (tmplen == 0) ? 1024 : tmplen * 2;
+	  tmp = xrealloc (tmp, tmplen);
+	}
+      strcpy (tmp, symname);
+
+      if (parse_method (tmp, &ntype, &nclass, &ncategory, &nselector) == NULL)
+	continue;
+      
+      if ((type != '\0') && (ntype != type))
+	continue;
+
+      if ((class != NULL) && ((nclass == NULL) || (strcmp (class, nclass) != 0)))
+	continue;
+
+      if ((category != NULL) && ((ncategory == NULL) || (strcmp (category, ncategory) != 0)))
+	continue;
+
+      if ((selector != NULL) && ((nselector == NULL) || (strcmp (selector, nselector) != 0)))
+	continue;
+
+      sym = find_pc_function (SYMBOL_VALUE_ADDRESS (msymbol));
+      if (sym != NULL)
+        {
+          const char    *newsymname = SYMBOL_DEMANGLED_NAME (sym);
+	  
+          if (newsymname == NULL)
+            newsymname = SYMBOL_NAME (sym);
+          if (strcmp (symname, newsymname) == 0)
+            {
+              /* found a high-level method sym: swap it into the
+                 lower part of sym_arr (below num_debuggable) */
+              if (syms != NULL)
+                {
+                  syms[csym] = syms[cdebug];
+                  syms[cdebug] = sym;
+                }
+              csym++;
+              cdebug++;
+            }
+          else
+            {
+              warning ("debugging symbol \"%s\" does not match minimal symbol (\"%s\"); ignoring",
+                       newsymname, symname);
+              if (syms != NULL)
+                syms[csym] = (struct symbol *) msymbol;
+              csym++;
+            }
+        }
+      else 
+	{
+	  /* found a non-debuggable method symbol */
+	  if (syms != NULL)
+	    syms[csym] = (struct symbol *) msymbol;
+	  csym++;
+	}
+    }
+
+  if (nsym != NULL)
+    *nsym = csym;
+  if (ndebug != NULL)
+    *ndebug = cdebug;
+}
+
+char *find_imps (struct symtab *symtab, struct block *block,
+		 char *method, struct symbol **syms, unsigned int *nsym, 
+		 unsigned int *ndebug) 
+{
+  char type = '\0';
+  char *class = NULL;
+  char *category = NULL;
+  char *selector = NULL;
+
+  unsigned int csym = 0;
+  unsigned int cdebug = 0;
+
+  unsigned int ncsym = 0;
+  unsigned int ncdebug = 0;
+
+  char *buf = NULL;
+  char *tmp = NULL;
+
+  CHECK (nsym != NULL);
+  CHECK (ndebug != NULL);
+
+  if (nsym != NULL)
+    *nsym = 0;
+  if (ndebug != NULL)
+    *ndebug = 0;
+
+  buf = (char *) alloca (strlen (method) + 1);
+  strcpy (buf, method);
+  tmp = parse_method (buf, &type, &class, &category, &selector);
+
+  if (tmp == NULL) {
+    
+    struct symtab *sym_symtab = NULL;
+    struct symbol *sym = NULL;
+    struct minimal_symbol *msym = NULL;
+    
+    strcpy (buf, method);
+    tmp = parse_selector (buf, &selector);
+    
+    if (tmp == NULL)
+      return NULL;
+    
+    sym = lookup_symbol (selector, block, VAR_NAMESPACE, 0, &sym_symtab);
+    if (sym != NULL) 
+      {
+	if (syms)
+	  syms[csym] = sym;
+	csym++;
+	cdebug++;
+      }
+
+    if (sym == NULL)
+      msym = lookup_minimal_symbol (selector, 0, 0);
+
+    if (msym != NULL) 
+      {
+	if (syms)
+	  syms[csym] = msym;
+	csym++;
+      }
+  }
+
+  if (syms != NULL)
+    find_methods (symtab, type, class, category, selector, syms + csym, &ncsym, &ncdebug);
+  else
+    find_methods (symtab, type, class, category, selector, NULL, &ncsym, &ncdebug);
+
+  /* If we didn't find any methods, just return. */
+  if (ncsym == 0 && ncdebug == 0)
+    return method;
+
+  /* Take debug symbols from the second batch of symbols and swap them
+   * with debug symbols from the first batch.  Repeat until either the
+   * second section is out of debug symbols or the first section is
+   * full of debug symbols.  Either way we have all debug symbols
+   * packed to the beginning of the buffer.  */
+
+  if (syms != NULL) 
+    {
+      while ((cdebug < csym) && (ncdebug > 0))
+	{
+	  struct symbol *s = NULL;
+
+	  unsigned int i = cdebug;	          /* first non-debugging symbol */
+	  unsigned int j = csym + ncdebug -1; /* last of second batch of debug symbols */
+
+	  s = syms[j];
+	  syms[j] = syms[i];
+	  syms[i] = s;
+
+	  /* We've moved a symbol from the second debug section to the first one. */
+	  cdebug++;
+	  ncdebug--;
+	}
+    }
+
+  csym += ncsym;
+  cdebug += ncdebug;
+
+  if (nsym != NULL)
+    *nsym = csym;
+  if (ndebug != NULL)
+    *ndebug = cdebug;
+
+  if (syms == NULL)
+    return method + (tmp - buf);
+
+  if (csym > 1)
+    {
+      /* sort debuggable symbols */
+      if (cdebug > 1)
+	qsort (syms, cdebug, sizeof (struct minimal_symbol *), compare_classes);
+      
+      /* sort minimal_symbols */
+      if ((csym - cdebug) > 1)
+	qsort (&syms[cdebug], csym - cdebug, sizeof (struct minimal_symbol *), compare_classes);
+    }
+  syms[csym] = 0;		/* terminate the sym_arr list */
+
+  return method + (tmp - buf);
+}
+
+void 
+print_object_command (char *args, int from_tty)
+{
+  struct value *object, *function, *description;
+  CORE_ADDR string_addr;
+  int i = 0;
+  char c = -1;
+
+  if (!args || !*args)
+    error ("The 'print-object' command requires an argument (an Objective-C object)");
+
+  {
+    struct expression *expr = parse_expression (args);
+    register struct cleanup *old_chain = make_cleanup (free_current_contents, &expr);
+    int pc = 0;
+
+#if 1
+    object = expr->language_defn->evaluate_exp (builtin_type_void_data_ptr,
+						expr, &pc, EVAL_NORMAL);
+#else
+    object = evaluate_subexp (builtin_type_void_data_ptr, expr, &pc, EVAL_NORMAL);
+#endif
+    do_cleanups (old_chain);
+  }
+
+  if (!(function = find_function_in_inferior ("_NSPrintForDebugger")))
+    error ("Unable to locate _NSPrintForDebugger in child process");
+
+  description = call_function_by_hand (function, 1, &object);
+
+  if ((string_addr = value_as_long (description)) == 0)
+    error ("object returns null description");
+
+  read_memory (string_addr + i++, &c, 1);
+  if (c != '\0')
+    do
+      { /* read and print characters up to EOS */
+	QUIT;
+	printf_filtered ("%c", c);
+	read_memory (string_addr + i++, &c, 1);
+      } while (c != 0);
+  else
+    printf_filtered("<object returns empty description>");
+  printf_filtered ("\n");
+}
+
+/* The data structure 'methcalls' is used to detect method calls
+ * (thru ObjC runtime lib functions objc_msgSend, objc_msgSendSuper, etc.),
+ * and ultimately find the method being called.
+ */
+
+struct objc_methcall {
+  char *name;
+  CORE_ADDR (*stop_at) (CORE_ADDR); /* should return instance method to be called */
+  CORE_ADDR begin;		    /* start of pc range corresponding to method invocation */
+  CORE_ADDR end;		    /* end of pc range corresponding to method invocation */
+};
+
+static int resolve_msgsend PARAMS ((CORE_ADDR pc, CORE_ADDR *new_pc));
+static int resolve_msgsend_stret PARAMS ((CORE_ADDR pc, CORE_ADDR *new_pc));
+static int resolve_msgsend_super PARAMS ((CORE_ADDR pc, CORE_ADDR *new_pc));
+static int resolve_msgsend_super_stret PARAMS ((CORE_ADDR pc, CORE_ADDR *new_pc));
+
+static struct objc_methcall methcalls[] = {
+  { "_objc_msgSend", resolve_msgsend, 0, 0},
+  { "_objc_msgSend_stret", resolve_msgsend_stret, 0, 0},
+  { "_objc_msgSendSuper", resolve_msgsend_super, 0, 0},
+  { "_objc_msgSendSuper_stret", resolve_msgsend_super_stret, 0, 0},
+  { "_objc_getClass", NULL, 0, 0},
+  { "_objc_getMetaClass", NULL, 0, 0}
+};
+
+#define nmethcalls (sizeof (methcalls) / sizeof (methcalls[0]))
+
+/* The following function, "find_objc_msgsend", fills in the data structure
+ * "objc_msgs" by finding the addresses of each of the (currently four) 
+ * functions that it holds (of which objc_msgSend is the first).  This
+ * must be called each time symbols are loaded, in case the functions
+ * have moved for some reason.
+ */
+
+void 
+find_objc_msgsend (void)
+{
+  unsigned int i;
+  for (i = 0; i < nmethcalls; i++) {
+
+    struct minimal_symbol *func;
+
+    /* try both with and without underscore */
+    func = lookup_minimal_symbol (methcalls[i].name, NULL, NULL);
+    if ((func == NULL) && (methcalls[i].name[0] == '_')) {
+      func = lookup_minimal_symbol (methcalls[i].name + 1, NULL, NULL);
+    }
+    if (func == NULL) { 
+      methcalls[i].begin = 0;
+      methcalls[i].end = 0;
+      continue; 
+    }
+    
+    methcalls[i].begin = SYMBOL_VALUE_ADDRESS (func);
+    do {
+      methcalls[i].end = SYMBOL_VALUE_ADDRESS (++func);
+    } while (methcalls[i].begin == methcalls[i].end);
+  }
+}
+
+/* find_objc_msgcall (replaces pc_off_limits)
+ *
+ * ALL that this function now does is to determine whether the input 
+ * address ("pc") is the address of one of the Objective C message
+ * dispatch functions (mainly objc_msgSend or objc_msgSendSuper), and
+ * if so, it returns the address of the method that will be called.
+ *
+ * The old function "pc_off_limits" used to do a lot of other things
+ * in addition, such as detecting shared library jump stubs and 
+ * returning the address of the shlib function that would be called.
+ * That functionality has been moved into the SKIP_TRAMPOLINE_CODE
+ * and IN_SOLIB_TRAMPOLINE macros, which are resolved in the target-
+ * dependent modules.
+ */
+
+struct objc_submethod_helper_data {
+  CORE_ADDR (*f) (CORE_ADDR, CORE_ADDR *);
+  CORE_ADDR pc;
+  CORE_ADDR *new_pc;
+};
+
+int 
+find_objc_msgcall_submethod_helper (PTR arg)
+{
+  struct objc_submethod_helper_data *s = (struct objc_submethod_helper_data *) arg;
+  if (s->f (s->pc, s->new_pc) == 0) { 
+    return 1;
+  } else {
+    return 0;
+  }
+}
+
+int 
+find_objc_msgcall_submethod (f, pc, new_pc)
+     CORE_ADDR (*f) (CORE_ADDR, CORE_ADDR *);
+     CORE_ADDR pc;
+     CORE_ADDR *new_pc;
+{
+  struct objc_submethod_helper_data s;
+
+  s.f = f;
+  s.pc = pc;
+  s.new_pc = new_pc;
+
+  if (catch_errors (find_objc_msgcall_submethod_helper,
+		   (PTR) &s,
+		   "Unable to determine target of Objective-C method call (ignoring):\n",
+		   RETURN_MASK_ALL) == 0) {
+    return 1;
+  } else {
+    return 0;
+  }
+}
+
+int 
+find_objc_msgcall (CORE_ADDR pc, CORE_ADDR *new_pc)
+{
+  unsigned int i;
+
+  find_objc_msgsend ();
+  if (new_pc != NULL) { *new_pc = 0; }
+
+  for (i = 0; i < nmethcalls; i++) {
+    if ((pc >= methcalls[i].begin) && (pc < methcalls[i].end)) {
+      if (methcalls[i].stop_at != NULL) {
+	return find_objc_msgcall_submethod (methcalls[i].stop_at, pc, new_pc);
+      } else {
+	return 0;
+      }
+    }
+  }
+  return 0;
+}
+
+void
+_initialize_objc_language (void)
+{
+  add_language (&objc_language_defn);
+  add_info ("selectors", selectors_info, 	/* INFO SELECTORS command */
+	    "All Objective C selectors, or those matching REGEXP.");
+  add_info ("classes", classes_info, 		/* INFO CLASSES   command */
+	    "All Objective C classes, or those matching REGEXP.");
+  add_com ("print-object", class_vars, print_object_command, 
+	   "Ask an Objective-C object to print itself.\n");
+  add_com_alias ("po", "print-object", class_vars, 1);
+}
+
+#if defined (__powerpc__) || defined (__ppc__)
+static unsigned long FETCH_ARGUMENT (int i)
+{
+  return read_register (3 + i);
+}
+#elif defined (__i386__)
+static unsigned long FETCH_ARGUMENT (int i)
+{
+  CORE_ADDR stack = read_register (SP_REGNUM);
+  return read_memory_unsigned_integer (stack + (4 * (i + 1)), 4);
+}
+#elif defined (__sparc__)
+static unsigned long FETCH_ARGUMENT (int i)
+{
+  return read_register (O0_REGNUM + i);
+}
+#elif defined (__hppa__) || defined (__hppa)
+static unsigned long FETCH_ARGUMENT (int i)
+{
+  return read_register (R0_REGNUM + 26 - i);
+}
+#else
+#error unknown architecture
+#endif
+
+#if defined (__hppa__) || defined (__hppa)
+static CORE_ADDR CONVERT_FUNCPTR (CORE_ADDR pc)
+{
+  if (pc & 0x2) {
+    pc = (CORE_ADDR) read_memory_integer (pc & ~0x3, 4);
+  }
+  return pc;
+}
+#else
+static CORE_ADDR CONVERT_FUNCPTR (CORE_ADDR pc)
+{
+  return pc;
+}
+#endif
+
+static void 
+read_objc_method (CORE_ADDR addr, struct objc_method *method)
+{
+  method->name = read_memory_unsigned_integer (addr, 4);
+  method->types = read_memory_unsigned_integer (addr + 4, 4);
+  method->imp = read_memory_unsigned_integer (addr + 8, 4);
+}
+
+static 
+unsigned long read_objc_methlist_nmethods (CORE_ADDR addr)
+{
+  return read_memory_unsigned_integer (addr + 4, 4);
+}
+
+static void 
+read_objc_methlist_method (CORE_ADDR addr, unsigned long num, 
+			   struct objc_method *method)
+{
+  CHECK_FATAL (num < read_objc_methlist_nmethods (addr));
+  read_objc_method (addr + 8 + (12 * num), method);
+}
+  
+static void 
+read_objc_object (CORE_ADDR addr, struct objc_object *object)
+{
+  object->isa = read_memory_unsigned_integer (addr, 4);
+}
+
+static void 
+read_objc_super (CORE_ADDR addr, struct objc_super *super)
+{
+  super->receiver = read_memory_unsigned_integer (addr, 4);
+  super->class = read_memory_unsigned_integer (addr + 4, 4);
+};
+
+static void 
+read_objc_class (CORE_ADDR addr, struct objc_class *class)
+{
+  class->isa = read_memory_unsigned_integer (addr, 4);
+  class->super_class = read_memory_unsigned_integer (addr + 4, 4);
+  class->name = read_memory_unsigned_integer (addr + 8, 4);
+  class->version = read_memory_unsigned_integer (addr + 12, 4);
+  class->info = read_memory_unsigned_integer (addr + 16, 4);
+  class->instance_size = read_memory_unsigned_integer (addr + 18, 4);
+  class->ivars = read_memory_unsigned_integer (addr + 24, 4);
+  class->methods = read_memory_unsigned_integer (addr + 28, 4);
+  class->cache = read_memory_unsigned_integer (addr + 32, 4);
+  class->protocols = read_memory_unsigned_integer (addr + 36, 4);
+}
+
+CORE_ADDR
+find_implementation_from_class (CORE_ADDR class, CORE_ADDR sel)
+{
+  CORE_ADDR subclass = class;
+
+  while (subclass != 0) {
+
+    struct objc_class class_str;
+    unsigned mlistnum = 0;
+
+    read_objc_class (subclass, &class_str);
+
+    for (;;) {
+      CORE_ADDR mlist;
+      unsigned long nmethods;
+      unsigned long i;
+      
+      mlist = read_memory_unsigned_integer (class_str.methods + (4 * mlistnum), 4);
+      if (mlist == 0) { break; }
+
+      nmethods = read_objc_methlist_nmethods (mlist);
+
+      for (i = 0; i < nmethods; i++) {
+	struct objc_method meth_str;
+	read_objc_methlist_method (mlist, i, &meth_str);
+
+#if 0
+	fprintf (stderr, "checking method 0x%lx against selector 0x%lx\n", meth_str.name, sel);
+#endif
+
+	if (meth_str.name == sel) {
+	  return CONVERT_FUNCPTR (meth_str.imp);
+	}
+      }
+
+      mlistnum++;
+    }
+      
+    subclass = class_str.super_class;
+  }
+
+  return 0;
+}
+
+CORE_ADDR
+find_implementation (CORE_ADDR object, CORE_ADDR sel)
+{
+  struct objc_object ostr;
+
+  if (object == 0) { return 0; }
+  read_objc_object (object, &ostr);
+  if (ostr.isa == 0) { return 0; }
+
+  return find_implementation_from_class (ostr.isa, sel);
+}
+
+static int
+resolve_msgsend (CORE_ADDR pc, CORE_ADDR *new_pc)
+{
+  CORE_ADDR object;
+  CORE_ADDR sel;
+  CORE_ADDR res;
+
+  object = FETCH_ARGUMENT (0);
+  sel = FETCH_ARGUMENT (1);
+
+  res = find_implementation (object, sel);
+  if (new_pc != 0) { *new_pc = res; }
+  if (res == 0) { return 1; }
+  return 0;
+}
+
+static int
+resolve_msgsend_stret (CORE_ADDR pc, CORE_ADDR *new_pc)
+{
+  CORE_ADDR object;
+  CORE_ADDR sel;
+  CORE_ADDR res;
+
+  object = FETCH_ARGUMENT (1);
+  sel = FETCH_ARGUMENT (2);
+
+  res = find_implementation (object, sel);
+  if (new_pc != 0) { *new_pc = res; }
+  if (res == 0) { return 1; }
+  return 0;
+}
+
+static int
+resolve_msgsend_super (CORE_ADDR pc, CORE_ADDR *new_pc)
+{
+  struct objc_super sstr;
+
+  CORE_ADDR super;
+  CORE_ADDR sel;
+  CORE_ADDR res;
+
+  super = FETCH_ARGUMENT (0);
+  sel = FETCH_ARGUMENT (1);
+
+  read_objc_super (super, &sstr);
+  if (sstr.class == 0) { return 0; }
+  
+  res = find_implementation_from_class (sstr.class, sel);
+  if (new_pc != 0) { *new_pc = res; }
+  if (res == 0) { return 1; }
+  return 0;
+}
+
+static int
+resolve_msgsend_super_stret (CORE_ADDR pc, CORE_ADDR *new_pc)
+{
+  struct objc_super sstr;
+
+  CORE_ADDR super;
+  CORE_ADDR sel;
+  CORE_ADDR res;
+
+  super = FETCH_ARGUMENT (1);
+  sel = FETCH_ARGUMENT (2);
+
+  read_objc_super (super, &sstr);
+  if (sstr.class == 0) { return 0; }
+  
+  res = find_implementation_from_class (sstr.class, sel);
+  if (new_pc != 0) { *new_pc = res; }
+  if (res == 0) { return 1; }
+  return 0;
+}