Initial revision

From-SVN: r4077

1 files changed, 1378 insertions, 0 deletions

diff --git a/gcc/objc/archive.c b/gcc/objc/archive.c
new file mode 100644
index 0000000..8398984
--- /dev/null
+++ b/gcc/objc/archive.c
@@ -0,0 +1,1378 @@
+/* GNU Objective C Runtime archiving
+   Copyright (C) 1993 Free Software Foundation, Inc.
+
+Author: Kresten Krab Thorup
+
+This file is part of GNU CC.
+
+GNU CC 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, or (at your option) any later version.
+
+GNU CC 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
+   GNU CC; see the file COPYING.  If not, write to the Free Software
+   Foundation, 675 Mass Ave, Cambridge, MA 02139, USA.  */
+
+/* As a special exception, if you link this library with files compiled with
+   GCC to produce an executable, this does not cause the resulting executable
+   to be covered by the GNU General Public License. This exception does not
+   however invalidate any other reasons why the executable file might be
+   covered by the GNU General Public License.  */
+
+/*
+** Note: This version assumes that int and longs are both 32bit.
+**       Most API function are in the bottom of this file.
+*/
+
+#include "runtime.h"
+#include <objc/objc-archive.h>
+
+#define __objc_fatal(format, args...) \
+ { fprintf(stderr, "archining: "); \
+   fprintf(stderr, format, ## args); \
+   fprintf(stderr, "\n"); abort(); }
+
+/* Declare some functions... */
+
+static int
+objc_read_class (struct objc_typed_stream* stream, Class** class);
+
+static int
+objc_sizeof_type(const char* type);
+
+static int
+objc_write_use_common (struct objc_typed_stream* stream, unsigned int key);
+
+static int
+objc_write_register_common (struct objc_typed_stream* stream,
+			    unsigned int key);
+
+static int 
+objc_write_class (struct objc_typed_stream* stream,
+			 struct objc_class* class);
+
+static const char*
+__objc_skip_type (const char* type);
+
+static __inline__ int
+__objc_code_unsigned_char (unsigned char* buf, unsigned char val)
+{
+  if ((val&_B_VALUE) == val)
+    {
+      buf[0] = val|_B_SINT;
+      return 1;
+    }
+  else
+    {
+      buf[0] = _B_NINT|0x01;
+      buf[1] = val;
+      return 2;
+    }
+}
+
+int
+objc_write_unsigned_char (struct objc_typed_stream* stream,
+			  unsigned char value)
+{
+  unsigned char buf[sizeof (unsigned char)+1];
+  int len = __objc_code_unsigned_char (buf, value);
+  return (*stream->write)(stream->physical, buf, len);
+}
+
+static __inline__ int
+__objc_code_char (unsigned char* buf, char val)
+{
+  if (val >= 0)
+    return __objc_code_unsigned_char (buf, val);
+  else
+    {
+      buf[0] = _B_NINT|_B_SIGN|0x01;
+      buf[1] = -val;
+      return 2;
+    }
+}
+
+int
+objc_write_char (struct objc_typed_stream* stream, char value)
+{
+  unsigned char buf[sizeof (char)+1];
+  int len = __objc_code_char (buf, value);
+  return (*stream->write)(stream->physical, buf, len);
+}
+
+static __inline__ int
+__objc_code_unsigned_short (unsigned char* buf, unsigned short val)
+{
+  if (val <= 0xffU)
+    return __objc_code_unsigned_char (buf, val);
+
+  else 
+    {
+      buf[0] = _B_NINT|0x02;
+      buf[1] = val/0x100;
+      buf[2] = val%0x100;
+      return 3;
+    }
+}
+
+int
+objc_write_unsigned_short (struct objc_typed_stream* stream, unsigned short value)
+{
+  unsigned char buf[sizeof (unsigned short)+1];
+  int len = __objc_code_unsigned_short (buf, value);
+  return (*stream->write)(stream->physical, buf, len);
+}
+      
+static __inline__ int
+__objc_code_short (unsigned char* buf, short val)
+{
+  if (val > 0)
+    return __objc_code_unsigned_short (buf, val);
+
+  if (val > -0x7f)		/* val > -128 */
+    return __objc_code_char (buf, val);
+
+  else 
+    {
+      int len = __objc_code_unsigned_short (buf, -val);
+      buf[0] |= _B_SIGN;
+      return len;
+    }
+}
+
+int
+objc_write_short (struct objc_typed_stream* stream, short value)
+{
+  unsigned char buf[sizeof (short)+1];
+  int len = __objc_code_short (buf, value);
+  return (*stream->write)(stream->physical, buf, len);
+}
+      
+
+static __inline__ int
+__objc_code_unsigned_int (unsigned char* buf, unsigned int val)
+{
+  if (val < 0x10000)
+    return __objc_code_unsigned_short (buf, val%0x10000);
+
+  else if (val < 0x1000000)
+    {
+      buf[0] = _B_NINT|3;
+      buf[1] = val/0x10000;
+      buf[2] = (val%0x10000)/0x100;
+      buf[3] = val%0x100;
+      return 4;
+    }
+
+  else 
+    {
+      buf[0] = _B_NINT|4;
+      buf[1] = val/0x1000000;
+      buf[2] = (val%0x1000000)/0x10000;
+      buf[3] = (val%0x10000)/0x100;
+      buf[4] = val%0x100;
+      return 5;
+    }
+}
+
+int
+objc_write_unsigned_int (struct objc_typed_stream* stream, unsigned int value)
+{
+  unsigned char buf[sizeof(unsigned int)+1];
+  int len = __objc_code_unsigned_int (buf, value);
+  return (*stream->write)(stream->physical, buf, len);
+}
+
+static __inline__ int
+__objc_code_int (unsigned char* buf, int val)
+{
+  if (val >= 0)
+    return __objc_code_unsigned_int (buf, val);
+
+  if (val > -0x7f)
+    return __objc_code_char (buf, val);
+
+  else 
+    {
+      int len = __objc_code_unsigned_int (buf, -val);
+      buf[0] |= _B_SIGN;
+      return len;
+    }
+}
+
+int
+objc_write_int (struct objc_typed_stream* stream, int value)
+{
+  unsigned char buf[sizeof(int)+1];
+  int len = __objc_code_int (buf, value);
+  return (*stream->write)(stream->physical, buf, len);
+}
+
+int
+objc_write_string (struct objc_typed_stream* stream,
+		   const unsigned char* string, unsigned int nbytes)
+{
+  unsigned char buf[sizeof(unsigned int)+1];
+  int len = __objc_code_unsigned_int (buf, nbytes);
+  
+  if ((buf[0]&_B_CODE) == _B_SINT)
+    buf[0] = (buf[0]&_B_VALUE)|_B_SSTR;
+
+  else /* _B_NINT */
+    buf[0] = (buf[0]&_B_VALUE)|_B_NSTR;
+
+  if ((*stream->write)(stream->physical, buf, len) != 0)
+    return (*stream->write)(stream->physical, string, nbytes);
+  else
+    return 0;
+}
+
+int
+objc_write_string_atomic (struct objc_typed_stream* stream,
+			  unsigned char* string, unsigned int nbytes)
+{
+  unsigned int key;
+  if ((key = (unsigned int)hash_value_for_key (stream->stream_table, string)))
+    return objc_write_use_common (stream, key);
+  else
+    {
+      int length;
+      hash_add (&stream->stream_table, (void*)key=(unsigned int)string, string);
+      if ((length = objc_write_register_common (stream, key)))
+	return objc_write_string (stream, string, nbytes);
+      return length;
+    }
+}
+
+static int
+objc_write_register_common (struct objc_typed_stream* stream, unsigned int key)
+{
+  unsigned char buf[sizeof (unsigned int)+2];
+  int len = __objc_code_unsigned_int (buf+1, key);
+  if (len == 1)
+    {
+      buf[0] = _B_RCOMM|0x01;
+      buf[1] &= _B_VALUE;
+      return (*stream->write)(stream->physical, buf, len+1);
+    }
+  else
+    {
+      buf[1] = (buf[1]&_B_VALUE)|_B_RCOMM;
+      return (*stream->write)(stream->physical, buf+1, len);
+    }
+}
+
+static int
+objc_write_use_common (struct objc_typed_stream* stream, unsigned int key)
+{
+  unsigned char buf[sizeof (unsigned int)+2];
+  int len = __objc_code_unsigned_int (buf+1, key);
+  if (len == 1)
+    {
+      buf[0] = _B_UCOMM|0x01;
+      buf[1] &= _B_VALUE;
+      return (*stream->write)(stream->physical, buf, 2);
+    }
+  else
+    {
+      buf[1] = (buf[1]&_B_VALUE)|_B_UCOMM;
+      return (*stream->write)(stream->physical, buf+1, len);
+    }
+}
+
+static __inline__ int
+__objc_write_extension (struct objc_typed_stream* stream, unsigned char code)
+{
+  if (code <= _B_VALUE)
+    {
+      unsigned char buf = code|_B_EXT;
+      return (*stream->write)(stream->physical, &buf, 1);
+    }
+  else 
+    abort();
+}
+
+__inline__ int
+__objc_write_object (struct objc_typed_stream* stream, id object)
+{
+  unsigned char buf = '\0';
+  SEL write_sel = sel_get_uid ("write:");
+  if (object)
+    {
+      __objc_write_extension (stream, _BX_OBJECT);
+      objc_write_class (stream, object->class_pointer);
+      (*objc_msg_lookup(object, write_sel))(object, write_sel, stream);
+      return (*stream->write)(stream->physical, &buf, 1);
+    }
+  else
+    return objc_write_use_common(stream, 0);
+}
+
+int 
+objc_write_object (struct objc_typed_stream* stream, id object)
+{
+  unsigned int key;
+  if ((key = (unsigned int)hash_value_for_key (stream->stream_table, object)))
+    return objc_write_use_common (stream, key);
+
+  else if (object == nil)
+    return objc_write_use_common(stream, 0);
+
+  else
+    {
+      int length;
+      hash_add (&stream->stream_table, (void*)key=(unsigned int)object, object);
+      if ((length = objc_write_register_common (stream, key)))
+	return __objc_write_object (stream, object);
+      return length;
+    }
+}
+
+__inline__ int
+__objc_write_class (struct objc_typed_stream* stream, struct objc_class* class)
+{
+  unsigned char buf = '\0';
+  SEL write_sel = sel_get_uid ("write:");
+  __objc_write_extension (stream, _BX_CLASS);
+  objc_write_string_atomic(stream, (char*)class->name,
+			   strlen(class->name));
+  objc_write_unsigned_int (stream, CLS_GETNUMBER(class));
+  (*objc_msg_lookup(class, write_sel))(class, write_sel, stream);
+  return (*stream->write)(stream->physical, &buf, 1);
+}
+
+
+static int 
+objc_write_class (struct objc_typed_stream* stream,
+			 struct objc_class* class)
+{
+  unsigned int key;
+  if ((key = (unsigned int)hash_value_for_key (stream->stream_table, class)))
+    return objc_write_use_common (stream, key);
+  else
+    {
+      int length;
+      hash_add (&stream->stream_table, (void*)key=(unsigned int)class, class);
+      if ((length = objc_write_register_common (stream, key)))
+	return __objc_write_class (stream, class);
+      return length;
+    }
+}
+
+
+__inline__ int 
+__objc_write_selector (struct objc_typed_stream* stream, SEL selector)
+{
+  const char* sel_name = sel_get_name (selector);
+  __objc_write_extension (stream, _BX_SEL);
+  return objc_write_string (stream, sel_name, strlen(sel_name));
+}
+
+int 
+objc_write_selector (struct objc_typed_stream* stream, SEL selector)
+{
+  const char* sel_name = sel_get_name (selector);
+  unsigned int key;
+  if ((key = (unsigned int)hash_value_for_key (stream->stream_table, sel_name)))
+    return objc_write_use_common (stream, key);
+  else
+    {
+      int length;
+      hash_add (&stream->stream_table, (void*)key=(unsigned int)sel_name, (char*)sel_name);
+      if ((length = objc_write_register_common (stream, key)))
+	return __objc_write_selector (stream, selector);
+      return length;
+    }
+}
+
+
+
+/*
+** Read operations 
+*/
+
+__inline__ int
+objc_read_char (struct objc_typed_stream* stream, char* val)
+{
+  unsigned char buf;
+  int len;
+  len = (*stream->read)(stream->physical, &buf, 1);
+  if (len != 0)
+    {
+      if ((buf & _B_CODE) == _B_SINT)
+	(*val) = (buf & _B_VALUE);
+
+      else if ((buf & _B_NUMBER) == 1)
+	{
+	  len = (*stream->read)(stream->physical, val, 1);
+	  if (buf&_B_SIGN)
+	    (*val) = -1*(*val);
+	}
+
+      else
+	__objc_fatal("expected 8bit signed int, got %dbit int",
+		     (int)(buf&_B_NUMBER)*8);
+    }
+  return len;
+}
+
+
+__inline__ int
+objc_read_unsigned_char (struct objc_typed_stream* stream, unsigned char* val)
+{
+  unsigned char buf;
+  int len;
+  if ((len = (*stream->read)(stream->physical, &buf, 1)))
+    {
+      if ((buf & _B_CODE) == _B_SINT)
+	(*val) = (buf & _B_VALUE);
+
+      else if ((buf & _B_NUMBER) == 1)
+	len = (*stream->read)(stream->physical, val, 1);
+
+      else
+	__objc_fatal("expected 8bit unsigned int, got %dbit int",
+		     (int)(buf&_B_NUMBER)*8);
+    }
+  return len;
+}
+
+__inline__ int
+objc_read_short (struct objc_typed_stream* stream, short* value)
+{
+  unsigned char buf[sizeof(short)+1];
+  int len;
+  if ((len = (*stream->read)(stream->physical, buf, 1)))
+    {
+      if ((buf[0] & _B_CODE) == _B_SINT)
+	(*value) = (buf[0] & _B_VALUE);
+
+      else
+	{
+	  int pos = 1;
+	  int nbytes = buf[0] & _B_NUMBER;
+	  if (nbytes > sizeof (short))
+	    __objc_fatal("expected short, got bigger (%dbits)", nbytes*8);
+	  len = (*stream->read)(stream->physical, buf+1, nbytes);
+	  (*value) = 0;
+	  while (pos <= nbytes)
+	    (*value) = ((*value)*0x100) + buf[pos++];
+	  if (buf[0] & _B_SIGN)
+	    (*value) = -(*value);
+	}
+    }
+  return len;
+}
+
+__inline__ int
+objc_read_unsigned_short (struct objc_typed_stream* stream,
+			  unsigned short* value)
+{
+  unsigned char buf[sizeof(unsigned short)+1];
+  int len;
+  if ((len = (*stream->read)(stream->physical, buf, 1)))
+    {
+      if ((buf[0] & _B_CODE) == _B_SINT)
+	(*value) = (buf[0] & _B_VALUE);
+
+      else
+	{
+	  int pos = 1;
+	  int nbytes = buf[0] & _B_NUMBER;
+	  if (nbytes > sizeof (short))
+	    __objc_fatal("expected short, got int or bigger");
+	  len = (*stream->read)(stream->physical, buf+1, nbytes);
+	  (*value) = 0;
+	  while (pos <= nbytes)
+	    (*value) = ((*value)*0x100) + buf[pos++];
+	}
+    }
+  return len;
+}
+
+
+__inline__ int
+objc_read_int (struct objc_typed_stream* stream, int* value)
+{
+  unsigned char buf[sizeof(int)+1];
+  int len;
+  if ((len = (*stream->read)(stream->physical, buf, 1)))
+    {
+      if ((buf[0] & _B_CODE) == _B_SINT)
+	(*value) = (buf[0] & _B_VALUE);
+
+      else
+	{
+	  int pos = 1;
+	  int nbytes = buf[0] & _B_NUMBER;
+	  if (nbytes > sizeof (int))
+	    __objc_fatal("expected int, got bigger");
+	  len = (*stream->read)(stream->physical, buf+1, nbytes);
+	  (*value) = 0;
+	  while (pos <= nbytes)
+	    (*value) = ((*value)*0x100) + buf[pos++];
+	  if (buf[0] & _B_SIGN)
+	    (*value) = -(*value);
+	}
+    }
+  return len;
+}
+
+__inline__ int
+__objc_read_nbyte_uint (struct objc_typed_stream* stream,
+		       unsigned int nbytes, unsigned int* val)
+{
+  int len, pos = 0;
+  unsigned char buf[sizeof(unsigned int)+1];
+
+  if (nbytes > sizeof (int))
+    __objc_fatal("expected int, got bigger");
+
+  len = (*stream->read)(stream->physical, buf, nbytes);
+  (*val) = 0;
+  while (pos < nbytes)
+    (*val) = ((*val)*0x100) + buf[pos++];
+  return len;
+}
+  
+
+__inline__ int
+objc_read_unsigned_int (struct objc_typed_stream* stream,
+			unsigned int* value)
+{
+  unsigned char buf[sizeof(unsigned int)+1];
+  int len;
+  if ((len = (*stream->read)(stream->physical, buf, 1)))
+    {
+      if ((buf[0] & _B_CODE) == _B_SINT)
+	(*value) = (buf[0] & _B_VALUE);
+
+      else
+	len = __objc_read_nbyte_uint (stream, (buf[0] & _B_VALUE), value);
+
+    }
+  return len;
+}
+
+__inline__ int
+objc_read_string (struct objc_typed_stream* stream,
+		  char** string)
+{
+  unsigned char buf[sizeof(unsigned int)+1];
+  int len;
+  if ((len = (*stream->read)(stream->physical, buf, 1)))
+    {
+      unsigned int key = 0;
+
+      if ((buf[0]&_B_CODE) == _B_RCOMM)	/* register following */
+	{
+	  len = __objc_read_nbyte_uint(stream, (buf[0] & _B_VALUE), &key);
+	  len = (*stream->read)(stream->physical, buf, 1);
+	}
+
+      switch (buf[0]&_B_CODE) {
+      case _B_SSTR:
+	{
+	  int length = buf[0]&_B_VALUE;
+	  (*string) = (char*)malloc(length+1);
+	  if (key)
+	    hash_add (&stream->stream_table, (void*)key, *string);
+	  len = (*stream->read)(stream->physical, *string, length);
+	  (*string)[length] = '\0';
+	}
+	break;
+
+      case _B_UCOMM:
+	{
+	  len = __objc_read_nbyte_uint(stream, (buf[0] & _B_VALUE), &key);
+	  (*string) = hash_value_for_key (stream->stream_table, (void*)key);
+	}
+	break;
+
+      case _B_NSTR:
+	{
+	  unsigned int nbytes = buf[0]&_B_VALUE;
+	  len = __objc_read_nbyte_uint(stream, nbytes, &nbytes);
+	  if (len) {
+	    (*string) = (char*)malloc(nbytes);
+	    if (key)
+	      hash_add (&stream->stream_table, (void*)key, *string);
+	    len = (*stream->read)(stream->physical, *string, buf[0]&_B_VALUE);
+	    (*string)[nbytes] = '\0';
+	  }
+	}
+	break;
+	
+      default:
+	__objc_fatal("expected string, got opcode %c\n", (buf[0]&_B_CODE));
+      }
+    }
+
+  return len;
+}
+
+
+int
+objc_read_object (struct objc_typed_stream* stream, id* object)
+{
+  unsigned char buf[sizeof (unsigned int)];
+  int len;
+  if ((len = (*stream->read)(stream->physical, buf, 1)))
+    {
+      SEL read_sel = sel_get_uid ("read:");
+      unsigned int key = 0;
+
+      if ((buf[0]&_B_CODE) == _B_RCOMM)	/* register common */
+	{
+	  len = __objc_read_nbyte_uint(stream, (buf[0] & _B_VALUE), &key);
+	  len = (*stream->read)(stream->physical, buf, 1);
+	}
+
+      if (buf[0] == (_B_EXT | _BX_OBJECT))
+	{
+	  Class* class;
+
+	  /* get class */
+	  len = objc_read_class (stream, &class);
+
+	  /* create instance */
+	  (*object) = class_create_instance(class);
+
+	  /* register? */
+	  if (key)
+	    hash_add (&stream->stream_table, (void*)key, *object);
+
+	  /* send -read: */
+	  if (__objc_responds_to (*object, read_sel))
+	    (*get_imp(class, read_sel))(*object, read_sel, stream);
+
+	  /* check null-byte */
+	  len = (*stream->read)(stream->physical, buf, 1);
+	  if (buf[0] != '\0')
+	    __objc_fatal("expected null-byte, got opcode %c", buf[0]);
+	}
+
+      else if ((buf[0]&_B_CODE) == _B_UCOMM)
+	{
+	  if (key)
+	    __objc_fatal("cannot register use upcode...");
+	  len = __objc_read_nbyte_uint(stream, (buf[0] & _B_VALUE), &key);
+	  (*object) = hash_value_for_key (stream->stream_table, (void*)key);
+	}
+
+      else
+	__objc_fatal("expected object, got opcode %c", buf[0]);
+    }
+  return len;
+}
+
+static int
+objc_read_class (struct objc_typed_stream* stream, Class** class)
+{
+  unsigned char buf[sizeof (unsigned int)];
+  int len;
+  if ((len = (*stream->read)(stream->physical, buf, 1)))
+    {
+      SEL read_sel = sel_get_uid ("read:");
+      unsigned int key = 0;
+
+      if ((buf[0]&_B_CODE) == _B_RCOMM)	/* register following */
+	{
+	  len = __objc_read_nbyte_uint(stream, (buf[0] & _B_VALUE), &key);
+	  len = (*stream->read)(stream->physical, buf, 1);
+	}
+
+      if (buf[0] == (_B_EXT | _BX_CLASS))
+	{
+	  char* class_name;
+	  int version;
+
+	  /* get class */
+	  len = objc_read_string (stream, &class_name);
+	  (*class) = objc_get_class(class_name);
+	  free (class_name);
+
+	  /* register */
+	  if (key)
+	    hash_add (&stream->stream_table, (void*)key, *class);
+
+	  /* call +read: */
+	  (*objc_msg_lookup(*class, read_sel))(*class, read_sel, stream);
+
+	  objc_read_unsigned_int(stream, &version);
+	  hash_add (&stream->class_table, (*class)->name, (void*)version);
+
+	  /* check null-byte */
+	  len = (*stream->read)(stream->physical, buf, 1);
+	  if (buf[0] != '\0')
+	    __objc_fatal("expected null-byte, got opcode %c", buf[0]);
+	}
+
+      else if ((buf[0]&_B_CODE) == _B_UCOMM)
+	{
+	  if (key)
+	    __objc_fatal("cannot register use upcode...");
+	  len = __objc_read_nbyte_uint(stream, (buf[0] & _B_VALUE), &key);
+	  (*class) = hash_value_for_key (stream->stream_table, (void*)key);
+	  if (!*class)
+	    __objc_fatal("cannot find class for key %x", key);
+	}
+
+      else
+	__objc_fatal("expected class, got opcode %c", buf[0]);
+    }
+  return len;
+}
+
+int
+objc_read_selector (struct objc_typed_stream* stream, SEL* selector)
+{
+  unsigned char buf[sizeof (unsigned int)];
+  int len;
+  if ((len = (*stream->read)(stream->physical, buf, 1)))
+    {
+      unsigned int key = 0;
+
+      if ((buf[0]&_B_CODE) == _B_RCOMM)	/* register following */
+	{
+	  len = __objc_read_nbyte_uint(stream, (buf[0] & _B_VALUE), &key);
+	  len = (*stream->read)(stream->physical, buf, 1);
+	}
+
+      if (buf[0] == (_B_EXT|_BX_SEL)) /* selector! */
+	{
+	  char* selector_name;
+
+	  /* get selector */
+	  len = objc_read_string (stream, &selector_name);
+	  (*selector) = sel_get_uid(selector_name);
+	  free (selector_name);
+
+	  /* register */
+	  if (key)
+	    hash_add (&stream->stream_table, (void*)key, *selector);
+	}
+
+      else if ((buf[0]&_B_CODE) == _B_UCOMM)
+	{
+	  if (key)
+	    __objc_fatal("cannot register use upcode...");
+	  len = __objc_read_nbyte_uint(stream, (buf[0] & _B_VALUE), &key);
+	  (*selector) = hash_value_for_key (stream->stream_table, (void*)key);
+	}
+
+      else
+	__objc_fatal("expected selector, got opcode %c", buf[0]);
+    }
+  return len;
+}
+
+static int
+objc_sizeof_type(const char* type)
+{
+  switch(*type) {
+  case _C_ID: return sizeof(id);
+    break;
+
+  case _C_CLASS:
+    return sizeof(Class*);
+    break;
+
+  case _C_SEL:
+    return sizeof(SEL);
+    break;
+
+  case _C_CHR:
+    return sizeof(char);
+    break;
+    
+  case _C_UCHR:
+    return sizeof(unsigned char);
+    break;
+
+  case _C_SHT:
+    return sizeof(short);
+    break;
+
+  case _C_USHT:
+    return sizeof(unsigned short);
+    break;
+
+  case _C_INT:
+  case _C_LNG:
+    return sizeof(int);
+    break;
+
+  case _C_UINT:
+  case _C_ULNG:
+    return sizeof(unsigned int);
+    break;
+
+  case _C_ATOM:
+  case _C_CHARPTR:
+    return sizeof(char*);
+    break;
+
+  default:
+    fprintf(stderr, "objc_write_type: cannot parse typespec: %s\n", type);
+    abort();
+  }
+}
+
+
+static const char*
+__objc_skip_type (const char* type)
+{
+  switch (*type) {
+  case _C_ID:
+  case _C_CLASS:
+  case _C_SEL:
+  case _C_CHR:
+  case _C_UCHR:
+  case _C_CHARPTR:
+  case _C_ATOM:
+  case _C_SHT:
+  case _C_USHT:
+  case _C_INT:
+  case _C_UINT:
+  case _C_LNG:
+  case _C_ULNG:
+  case _C_FLT:
+  case _C_DBL:
+    return ++type;
+    break;
+
+  case _C_ARY_B:
+    while(isdigit(*++type));
+    type = __objc_skip_type(type);
+    if (*type == _C_ARY_E)
+      return ++type;
+    else
+      __objc_fatal("cannot parse typespec: %s", type);
+    break;
+
+  default:
+    fprintf(stderr, "objc_read_types: cannot parse typespec: %s\n", type);
+    abort();
+  }
+}
+
+/*
+** USER LEVEL FUNCTIONS
+*/
+
+/*
+** Write one object, encoded in TYPE and pointed to by DATA to the
+** typed stream STREAM.  
+*/
+
+int
+objc_write_type(TypedStream* stream, const char* type, const void* data)
+{
+  switch(*type) {
+  case _C_ID:
+    return objc_write_object (stream, *(id*)data);
+    break;
+
+  case _C_CLASS:
+    return objc_write_class (stream, *(Class**)data);
+    break;
+
+  case _C_SEL:
+    return objc_write_selector (stream, *(SEL*)data);
+    break;
+
+  case _C_CHR:
+    return objc_write_char(stream, *(char*)data);
+    break;
+    
+  case _C_UCHR:
+    return objc_write_unsigned_char(stream, *(unsigned char*)data);
+    break;
+
+  case _C_SHT:
+    return objc_write_short(stream, *(short*)data);
+    break;
+
+  case _C_USHT:
+    return objc_write_unsigned_short(stream, *(unsigned short*)data);
+    break;
+
+  case _C_INT:
+  case _C_LNG:
+    return objc_write_int(stream, *(int*)data);
+    break;
+
+  case _C_UINT:
+  case _C_ULNG:
+    return objc_write_unsigned_int(stream, *(unsigned int*)data);
+    break;
+
+  case _C_CHARPTR:
+    return objc_write_string (stream, (char*)data, strlen((char*)data));
+    break;
+
+  case _C_ATOM:
+    return objc_write_string_atomic (stream, (char*)data, strlen((char*)data));
+    break;
+
+  case _C_ARY_B:
+    {
+      int len = atoi(type+1);
+      while (isdigit(*++type));
+      return objc_write_array (stream, type, len, data);
+    }
+    break; 
+
+  default:
+    fprintf(stderr, "objc_write_type: cannot parse typespec: %s\n", type);
+    abort();
+  }
+}
+
+/*
+** Read one object, encoded in TYPE and pointed to by DATA to the
+** typed stream STREAM.  DATA specifies the address of the types to
+** read.  Expected type is checked against the type actually present
+** on the stream. 
+*/
+
+int
+objc_read_type(TypedStream* stream, const char* type, void* data)
+{
+  char c;
+  switch(c = *type) {
+  case _C_ID:
+    return objc_read_object (stream, (id*)data);
+    break;
+
+  case _C_CLASS:
+    return objc_read_class (stream, (Class**)data);
+    break;
+
+  case _C_SEL:
+    return objc_read_selector (stream, (SEL*)data);
+    break;
+
+  case _C_CHR:
+    return objc_read_char (stream, (char*)data);
+    break;
+    
+  case _C_UCHR:
+    return objc_read_unsigned_char (stream, (unsigned char*)data);
+    break;
+
+  case _C_SHT:
+    return objc_read_short (stream, (short*)data);
+    break;
+
+  case _C_USHT:
+    return objc_read_unsigned_short (stream, (unsigned short*)data);
+    break;
+
+  case _C_INT:
+  case _C_LNG:
+    return objc_read_int (stream, (int*)data);
+    break;
+
+  case _C_UINT:
+  case _C_ULNG:
+    return objc_read_unsigned_int (stream, (unsigned int*)data);
+    break;
+
+  case _C_CHARPTR:
+  case _C_ATOM:
+    return objc_read_string (stream, (char**)data);
+    break;
+
+  case _C_ARY_B:
+    {
+      int len = atoi(type+1);
+      while (isdigit(*++type));
+      return objc_read_array (stream, type, len, data);
+    }
+    break; 
+
+  default:
+    fprintf(stderr, "objc_write_type: cannot parse typespec: %s\n", type);
+    abort();
+  }
+}
+
+/*
+** Write the object specified by the template TYPE to STREAM.  Last
+** arguments specify addresses of values to be written.  It might 
+** seem surprising to specify values by address, but this is extremely
+** convenient for copy-paste with objc_read_types calls.  A more
+** down-to-the-earth cause for this passing of addresses is that values
+** of arbitrary size is not well supported in ANSI C for functions with
+** variable number of arguments.
+*/
+
+int 
+objc_write_types (TypedStream* stream, const char* type, ...)
+{
+  va_list args;
+  const char *c;
+  int res = 0;
+
+  va_start(args, type);
+
+  for (c = type; *c; c = __objc_skip_type (c))
+    {
+      switch(*c) {
+      case _C_ID:
+	res = objc_write_object (stream, *va_arg (args, id*));
+	break;
+
+      case _C_CLASS:
+	res = objc_write_class (stream, *va_arg(args, Class**));
+	break;
+
+      case _C_SEL:
+	res = objc_write_selector (stream, *va_arg(args, SEL*));
+	break;
+	
+      case _C_CHR:
+	res = objc_write_char (stream, *va_arg (args, char*));
+	break;
+	
+      case _C_UCHR:
+	res = objc_write_unsigned_char (stream,
+					*va_arg (args, unsigned char*));
+	break;
+	
+      case _C_SHT:
+	res = objc_write_short (stream, *va_arg(args, short*));
+	break;
+
+      case _C_USHT:
+	res = objc_write_unsigned_short (stream,
+					 *va_arg(args, unsigned short*));
+	break;
+
+      case _C_INT:
+      case _C_LNG:
+	res = objc_write_int(stream, *va_arg(args, int*));
+	break;
+	
+      case _C_UINT:
+      case _C_ULNG:
+	res = objc_write_unsigned_int(stream, *va_arg(args, unsigned int*));
+	break;
+
+      case _C_CHARPTR:
+	{
+	  char* str = va_arg(args, char*);
+	  res = objc_write_string (stream, str, strlen(str));
+	}
+	break;
+
+      case _C_ATOM:
+	{
+	  char* str = va_arg(args, char*);
+	  res = objc_write_string_atomic (stream, str, strlen(str));
+	}
+	break;
+
+      case _C_ARY_B:
+	{
+	  int len = atoi(c+1);
+	  const char* t = c;
+	  while (isdigit(*++t));
+	  res = objc_write_array (stream, t, len, va_arg(args, void*));
+	  t = __objc_skip_type (t);
+	  if (*t != _C_ARY_E)
+	    __objc_fatal("expected `]', got: %s", t);
+	}
+	break; 
+	
+      default:
+	fprintf(stderr, "objc_write_type: cannot parse typespec: %s\n", type);
+	abort();
+      }
+    }
+  va_end(args);
+  return res;
+}
+
+
+/* 
+** Last arguments specify addresses of values to be read.  Expected
+** type is checked against the type actually present on the stream. 
+*/
+
+int 
+objc_read_types(TypedStream* stream, const char* type, ...)
+{
+  va_list args;
+  const char *c;
+  int res = 0;
+
+  va_start(args, type);
+
+  for (c = type; *c; c = __objc_skip_type(c))
+    {
+      switch(*c) {
+      case _C_ID:
+	res = objc_read_object(stream, va_arg(args, id*));
+	break;
+
+      case _C_CLASS:
+	res = objc_read_class(stream, va_arg(args, Class**));
+	break;
+
+      case _C_SEL:
+	res = objc_read_selector(stream, va_arg(args, SEL*));
+	break;
+	
+      case _C_CHR:
+	res = objc_read_char(stream, va_arg(args, char*));
+	break;
+	
+      case _C_UCHR:
+	res = objc_read_unsigned_char(stream, va_arg(args, unsigned char*));
+	break;
+	
+      case _C_SHT:
+	res = objc_read_short(stream, va_arg(args, short*));
+	break;
+
+      case _C_USHT:
+	res = objc_read_unsigned_short(stream, va_arg(args, unsigned short*));
+	break;
+
+      case _C_INT:
+      case _C_LNG:
+	res = objc_read_int(stream, va_arg(args, int*));
+	break;
+	
+      case _C_UINT:
+      case _C_ULNG:
+	res = objc_read_unsigned_int(stream, va_arg(args, unsigned int*));
+	break;
+
+      case _C_CHARPTR:
+      case _C_ATOM:
+	{
+	  char** str = va_arg(args, char**);
+	  res = objc_read_string (stream, str);
+	}
+	break;
+
+      case _C_ARY_B:
+	{
+	  int len = atoi(c+1);
+	  const char* t = c;
+	  while (isdigit(*++t));
+	  res = objc_read_array (stream, t, len, va_arg(args, void*));
+	  t = __objc_skip_type (t);
+	  if (*t != _C_ARY_E)
+	    __objc_fatal("expected `]', got: %s", t);
+	}
+	break; 
+	
+      default:
+	fprintf(stderr, "objc_read_type: cannot parse typespec: %s\n", type);
+	abort();
+      }
+    }
+  va_end(args);
+  return res;
+}
+
+/*
+** Write an array of COUNT elements of TYPE from the memory address DATA.
+** This is equivalent of objc_write_type (stream, "[N<type>]", data)
+*/
+
+int
+objc_write_array (TypedStream* stream, const char* type,
+		  int count, const void* data)
+{
+  int off = objc_sizeof_type(type);
+  const char* where = data;
+
+  while (count-- > 0)
+    {
+      objc_write_type(stream, type, where);
+      where += off;
+    }
+  return 1;
+}
+
+/*
+** Read an array of COUNT elements of TYPE into the memory address
+** DATA.  The memory pointed to by data is supposed to be allocated
+** by the callee.  This is equivalent of 
+**   objc_read_type (stream, "[N<type>]", data)
+*/
+
+int
+objc_read_array (TypedStream* stream, const char* type,
+		 int count, void* data)
+{
+  int off = objc_sizeof_type(type);
+  char* where = (char*)data;
+
+  while (count-- > 0)
+    {
+      objc_read_type(stream, type, where);
+      where += off;
+    }
+  return 1;
+}
+
+static int 
+__objc_fread(FILE* file, char* data, int len)
+{
+  return fread(data, len, 1, file);
+}
+
+static int 
+__objc_fwrite(FILE* file, char* data, int len)
+{
+  return fwrite(data, len, 1, file);
+}
+
+static int
+__objc_feof(FILE* file)
+{
+  return feof(file);
+}
+
+static int 
+__objc_no_write(FILE* file, char* data, int len)
+{
+  __objc_fatal ("TypedStream not open for writing");
+}
+
+static int 
+__objc_no_read(FILE* file, char* data, int len)
+{
+  __objc_fatal ("TypedStream not open for reading");
+}
+
+static int
+__objc_read_typed_stream_signature (TypedStream* stream)
+{
+  char buffer[80];
+  int pos = 0;
+  do
+    (*stream->read)(stream->physical, buffer+pos, 1);
+  while (buffer[pos++] != '\0');
+  sscanf (buffer, "GNU TypedStream %d", &stream->version);
+  if (stream->version != OBJC_TYPED_STREAM_VERSION)
+    __objc_fatal ("cannot handle TypedStream version %d", stream->version);
+}
+
+static int
+__objc_write_typed_stream_signature (TypedStream* stream)
+{
+  char buffer[80];
+  sprintf(buffer, "GNU TypedStream %d", OBJC_TYPED_STREAM_VERSION);
+  stream->version = OBJC_TYPED_STREAM_VERSION;
+  (*stream->write)(stream->physical, buffer, strlen(buffer)+1);
+}
+
+/*
+** Open the stream PHYSICAL in MODE
+*/
+
+TypedStream* 
+objc_open_typed_stream (FILE* physical, int mode)
+{
+  int fflush(FILE*);
+
+  TypedStream* s = (TypedStream*)malloc(sizeof(TypedStream));
+
+  s->mode = mode;
+  s->physical = physical;
+  s->stream_table = hash_new(64,
+			     (hash_func_type)hash_ptr,
+			     (compare_func_type)compare_ptrs);
+  s->eof = (objc_typed_eof_func)__objc_feof;
+  s->flush = (objc_typed_flush_func)fflush;
+  if (mode == OBJC_READONLY)
+    {
+      s->class_table = hash_new(8, (hash_func_type)hash_string,
+				(compare_func_type)compare_strings);
+      s->read = (objc_typed_read_func)__objc_fread;
+      s->write = (objc_typed_write_func)__objc_no_write;
+      __objc_read_typed_stream_signature (s);
+    }
+  else if (mode == OBJC_WRITEONLY)
+    {
+      s->class_table = 0;
+      s->read = (objc_typed_read_func)__objc_no_read;
+      s->write = (objc_typed_write_func)__objc_fwrite;
+      __objc_write_typed_stream_signature (s);
+    }      
+  else
+    {
+      objc_close_typed_stream (s);
+      return NULL;
+    }
+  s->type = OBJC_FILE_STREAM;
+  return s;
+}
+
+/*
+** Open the file named by FILE_NAME in MODE
+*/
+
+TypedStream*
+objc_open_typed_stream_for_file (const char* file_name, int mode)
+{
+  FILE* file = NULL;
+  TypedStream* s;
+
+  if (mode == OBJC_READONLY)
+    file = fopen (file_name, "r");
+  else
+    file = fopen (file_name, "w");
+
+  if (file)
+    {
+      s = objc_open_typed_stream (file, mode);
+      if (s)
+	s->type |= OBJC_MANAGED_STREAM;
+      return s;
+    }
+  else
+    return NULL;
+}
+
+/*
+** Close STREAM freeing the structure it self.  If it was opened with 
+** objc_open_typed_stream_for_file, the file will also be closed.
+*/
+
+void
+objc_close_typed_stream (TypedStream* stream)
+{
+  if (stream->type == (OBJC_MANAGED_STREAM | OBJC_FILE_STREAM))
+    fclose ((FILE*)stream->physical);
+  hash_delete (stream->stream_table);
+  if (stream->mode == OBJC_READONLY)
+    hash_delete (stream->class_table);
+  free (stream);
+}
+
+BOOL
+objc_end_of_typed_stream (TypedStream* stream)
+{
+  return (*stream->eof)(stream->physical);
+}
+
+void
+objc_flush_typed_stream (TypedStream* stream)
+{
+  (*stream->flush)(stream->physical);
+}
+