Add ruby-dl

git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@2324 b2dd03c8-39d4-4d8f-98ff-823fe69b080e

29 files changed, 5871 insertions, 0 deletions

diff --git a/ext/dl/Changes b/ext/dl/Changes
new file mode 100644
index 0000000000..d02dd9ed42
--- /dev/null
+++ b/ext/dl/Changes
@@ -0,0 +1,166 @@
+1.0.2 -> 1.1.0
+---------------
+* Use inline assembler for gcc on ix86 as a default.
+* Add DL::Importable module (defined in "dl/import.rb").
+
+1.0.1 -> 1.0.2
+--------------
+* Fix an installation problem, thanks to Nakada.
+* Handle#to_i, to_ptr is added.
+* lib/dl/win32.rb is added for Win32API compatibility.
+
+1.0 -> 1.0.1
+-------------
+* Fix PtrData#to_s.
+* Add PtrData#to_str(size).
+
+0.9 -> 1.0 (stable)
+-------------------
+* PtrData object keeps size data if possible.
+* PtrData#size is added.
+* LoadLibary(), FreeLibrary() and GetProcAddress() are used on
+  windows instead of dlopen(),dlclose() and dlsym().
+
+0.8.1 -> 0.9
+------------
+* You can use inline assembler to constracting the function calls by
+  building the library using --with-asm options for extconf.rb.
+  But now this can work with GNU assembler on i386 machines. If you try
+  this mechanism, you can get rid of the limit of number of parameters.
+
+0.8 -> 0.8.1
+-------------
+* rb_dlsym_call() calls xmalloc() or dlmalloc() instread of
+  alloca() because of portability.
+
+* 'h2rb' get to parse the enumeration type.
+
+0.7.1 -> 0.8
+-------------
+* If <type> of Symbol.new(addr, name = nil, type = nil) is nil,
+  it returns a DataPtr object.
+
+* PtrData#[] returns the memory image, and PtrData#[]= is used
+  to copy the memory image to specified area.
+
+* Handle#sym(symbol_name) returns a PtrData object, and
+  Handle#sym(symbol_name, type_spec) returns a Symbol object.
+
+* We can use the number following a type specifier to represent the
+  length of an array. For example, if you'd like to represent the
+  following structure, we use 'C1024I' when using PtrData#struct! or
+  PtrData#union!.
+
+    struct {
+      char name[1024];
+      int  age;
+    }
+
+0.6 -> 0.7
+-----------
+* type `ANY_FUNC' is removed, it is because the method for
+  calling the function obtained by dlsym() was changed.
+
+* `char', `short' and `float' types are supported, if you'd
+  like to use those type exactly and run extconf.rb with the
+  option `--with-type-{char,short,float}'.
+
+* `DL.sizeof(type)' returns the size of the <type> with the
+  alignment. so `DL.sizeof("C") + DL.sizeof("L")' is not equal
+  to `DL.sizeof("CL")'. it is assumed that the latter returns
+  the enough size for the following structure:
+    struct foo { char x; long y; }
+  but it may not equal to `sizeof(struct foo)' of C.
+
+* new methods:
+  - PtrData#define_data_type
+  - PtrData#struct!
+  - PtrData#union!
+  - PtrData#data_type
+  - PtrData#[]
+  - PtrData#[]=
+  - Symbol.new
+
+0.5 -> 0.6
+-----------
+* DL.set_callback is changed.
+  - set_callback(type,num,proc)   [old style]
+  - set_callback(type,num){...}   [new style]
+
+* the handle object don't call dlclose() at the time of GC.
+  if you need to call dlclose(), use Handle#enable_close.
+
+* new methods:
+  - PtrData#{+,-}
+  - PtrData#{+@,-@} (= PtrData#{ptr,ref})
+  - DL.malloc
+  - DL.strdup
+  - MemorySpace.each
+
+* some memory leaks are fixed.
+
+0.4 -> 0.5
+----------
+* new methods:
+  - DL.dlopen (= DL::Handle.new)
+  - PtrData#ref
+  - PtrData#==
+  - PtrData#eql?
+  - String#to_ptr
+  - Handle#enable_close
+  - Handle#disable_close
+
+* PtrData#ptr returns the pointed value (*ptr).
+
+* PtrData#ref returns the reference (&ptr).
+  `ptr.ref.ptr == ptr' must be true.
+
+(experiment)
+* the callback function is supported.
+
+* new methods:
+  - DL.set_callback
+  - DL.get_callback
+
+
+0.3 -> 0.4
+----------
+* Symbol#call supports the mechanism for converting any object
+  to PtrData object automatically using 'to_ptr' method, if the
+  argument type is 'P' or 'p'.
+
+* new methods are added.
+  - Array#to_ptr
+  - IO#to_ptr
+  - Symbol#to_ptr
+  - Symbol#[]
+
+* new constant is added.
+  - DL::FREE is a symbol object for representing the function 'free'.
+
+* the specification of PtrData#free was changed.
+
+* new internal functions are added.
+  - rb_dlptr2cptr()
+  - rb_dlsym2csym()
+  - rb_dlsym_new()
+
+* 'dl.h' is new file.
+
+* 'extconf.rb' and 'depend' ware modified so that we can build
+  the library in a directory except 'srcdir' (by N. Nakada).
+
+* (experimental) 'h2rb' is a new script which converts C header
+  files into ruby scripts.
+
+0.2 -> 0.3
+----------
+* many useful functions ware added (by Akinori Musha).
+
+* the type of 'long' was supported (by Akinori Musha).
+
+* some methods of the PtrData ware added for handling pointer data.
+
+* bug fix for mutable int and long.
+
+* the type of array was supported.
diff --git a/ext/dl/MANIFEST b/ext/dl/MANIFEST
new file mode 100644
index 0000000000..a98d6f5b34
--- /dev/null
+++ b/ext/dl/MANIFEST
@@ -0,0 +1,24 @@
+.cvsignore
+Changes
+MANIFEST
+README
+README.html
+depend
+dl.c
+dl.h
+dl.def
+extconf.rb
+h2rb
+handle.c
+mkcall.rb
+mkcallback.rb
+mkcbtable.rb
+ptr.c
+sym.c
+type.rb
+test/test.c
+test/test.rb
+sample/drives.rb
+sample/getch.rb
+sample/libc.rb
+sample/msgbox.rb
diff --git a/ext/dl/README b/ext/dl/README
new file mode 100644
index 0000000000..2463e48bb7
--- /dev/null
+++ b/ext/dl/README
@@ -0,0 +1,186 @@
+                                    Ruby/DL                                    
+                                                                               
+                    an interface to dynamic linking loader                     
+-------------------------------------------------------------------------------
+
+Ruby/DL
+
+`Ruby/DL' provides an interface to the dynamic linking loader.
+-------------------------------------------------------------------------------
+
+Installing
+
+    $ ruby extconf.rb    # to create the Makefile
+    $ make               # to build the library 'dl.so'
+    $ make libtest.so    # to build the C library 'libtest.so' for the test script
+    $ make test          # to run the test script
+    $ make install       # to install the library
+    $ make clean         # to remove the created files without Makefile
+    $ make distclean     # to remove the all created files
+
+-------------------------------------------------------------------------------
+
+Functions and Classes
+
+after loading the `dl' library, we get access to the module called `DL'. the DL
+module has the following constants, functions and classes.
+
+Constants
+
+VERSION
+MAJOR_VERSION
+MINOR_VERSION
+PATCH_VERSION
+RTLD_GLOBAL
+RTLD_LAZY
+RTLD_NOW
+MAX_ARG
+MAX_CBARG
+MAX_CBENT
+
+Functions
+
+handle = dlopen(lib){|handle| ... }
+    is quite equal to `Handle.new(lib)'
+sym = set_callback(cbtype, entry){|args| ... }
+sym = set_callback(cbtype, entry, proc)
+    makes entry-th pre-defined function to call the proc or given block. the 
+    entry-th pre-defined function is specified by cbtype and entry. cbtype is a
+    prototype of the callback. see also the section `Type specifiers' about 
+    cbtype.
+sym = get_callback(cbtype, entry)
+    returns the Proc object which is given by the above function
+    `set_callback'.
+ptr = malloc(size, [free = nil])
+    allocates the size bytes, and returns the pointer as a PtrData object ptr.
+ptr = strdup(str)
+    returns a PtrData object ptr which represents the pointer to a new string
+    which is a duplicate of the string str.
+size = sizeof(type)
+    returns the size of type. `sizeof("C") + sizeof("L")' is not equal to
+    `sizeof("CL")'. the latter is assumed to returns the enough size of the
+    structure `struct foo { char c; long l; }', but the size may not equal to
+    `sizeof(foo)' of C.
+
+class Handle
+
+handle = Handle.new(lib){|handle| ... }
+    opens a library lib and returns a Handle object handle. if a block is
+    given, the handle is automatically closed as the block ends.
+Handle#close
+    closes the handle opened by the above Handle.new(lib).
+sym = Handle#sym(func, prototype = "0")
+sym = Handle#[func, prototype = nil]
+    obtains the pointer to a function called func and returns a Symbol object
+    or a DataPtr object. prototype is a string which consists of type
+    specifiers, it indicates the function's prototype. see also the section
+    `Type specifiers'.
+
+class Symbol
+
+sym = Symbol.new(addr, type = nil, name = nil)
+    creates the Symbol object sym with the type type if type is not nil. addr
+    is the address where the function is allocated. If type is nil, it returns
+    a DataPtr object.
+Symbol::char2type(char)
+    takes a character char that represents a type and returns the type
+    specifier of the C language.
+str = Symbol#proto()
+    returns the function prototype.
+str = Symbol#name()
+    Returns the function name.
+str = Symbol#cproto()
+str = Symbol#to_s()
+    returns the prototype of the C language.
+str = Symbol#inspect()
+    returns the inspectable string.
+r,rs = Symbol#call(arg1,arg2,...,argN)
+r,rs = Symbol#[](arg1,arg2,...,argN)
+    calls the function with parameters arg1, arg2, ..., argN. and the result
+    consists of the return value r and parameters rs. rs is an array.
+ptr = Symbol#to_ptr
+    returns the corresponding PtrData object ptr.
+
+class PtrData
+
+ptr = PtrData.new(addr, [free = nil])
+    returns the PtrData object representing the pointer which indicates the
+    address addr. GC frees the memory using the free function.
+PtrData#free=(sym)
+    if you specify a symbol object sym, GC frees the memory using the function
+    represented by sym.
+sym = PtrData#free
+    returns a symbol object sym which is used when GC frees the memory. it
+    usually configured by `PtrData#free=' or `PtrData.new'.
+size = PtrData#size, PtrData#size=(size)
+    gets and sets allocated size of the memory.
+ary = PtrData#to_a(type, [size])
+    returns an array of the type which specified with type. type must be one of
+    'S','P','I','L','D' and 'F'.
+str = PtrData#to_s([len])
+    returns a string which length is len. if len is omitted, the end of the
+    string is '\0'.
+ptr = PtrData#ptr,+@
+    returns the pointed value as a PtrData object ptr.
+ptr = PtrData#ref,-@
+    returns the reference as a PtrData object ptr.
+ptr = PtrData#+
+    returns the PtrData object
+ptr = PtrData#-
+    returns the PtrData object
+PtrData#struct!(type, *members)
+    defines the data type to get access to a structure member with a symbol.
+    (see also PtrData#[])
+PtrData#union!(type, *members)
+    defines the data type to get access to a union member with a symbol. (see
+    also PtrData#[])
+val = PtrData#[key], PtrData#[key, num = 0]
+    if the key is a string or symbol, this method returns the value of the
+    structure/union member which has the type defined by PtrData#
+    {struct!,union!}. if the key is a integer value and this object represents
+    the pointer ptr, it returns the value of `(ptr + key).to_s(num)'
+PtrData#[key,num]=val, PtrData#[key]=val
+    if the key is a string or symbol, this method substitute the value of the
+    structure/union member with val. if the key is a integer value and val is a
+    string, this method copies num bytes of val to the memory area ptr using
+    memcpy(3).
+
+-------------------------------------------------------------------------------
+
+Type specifiers
+
+the prototype consists of the following type specifiers, first element of 
+prototype represents the type of return value, and remaining elements represent
+the type of each argument.
+
+    C : a character (char)
+    c : a pointer to a character (char *)
+    H : a short integer (short)
+    h : a pointer to a short integer (short *)
+    I : an integer (char, short, int)
+    i : a pointer to an integer (char *, short *, int *)
+    L : a long integer (long)
+    l : a pointer to a long integer (long *)
+    F : a real (float)
+    f : a pointer to a real (float *)
+    D : a real (double)
+    d : a pointer to a real (double *)
+    S : an immutable string (const char *)
+    s : a mutable string (char *)
+    A : an array (const type[])
+    a : a mutable array (type[])
+    P : a pointer (void *)
+    p : a mutable object (void *)
+    0 : void function (this must be a first character of the prototype)
+
+the cbtype consists of type specifiers 0, I, L, D and P.
+for example:
+
+    DL.set_callback('IPP',0){|ptr1,ptr2|
+      str1 = ptr1.ptr.to_s
+      str2 = ptr2.ptr.to_s
+      return str1 <=> str2
+    }
+
+-------------------------------------------------------------------------------
+ttate@kt.jaist.ac.jp
diff --git a/ext/dl/README.html b/ext/dl/README.html
new file mode 100644
index 0000000000..b248cce1f3
--- /dev/null
+++ b/ext/dl/README.html
@@ -0,0 +1,247 @@
+<html>
+<head><title>Ruby/DL</title></head>
+<body>
+<center>
+ <h2>Ruby/DL</h2>
+ an interface to dynamic linking loader
+</center>
+
+<hr>
+<h2>Ruby/DL</h2>
+
+`Ruby/DL' provides an interface to the dynamic linking loader.
+
+<hr>
+<h2>Installing</h2>
+
+<blockquote>
+<pre>
+$ ruby extconf.rb    # to create the Makefile
+$ make               # to build the library 'dl.so'
+$ make libtest.so    # to build the C library 'libtest.so' for the test script
+$ make test          # to run the test script
+$ make install       # to install the library
+$ make clean         # to remove the created files without Makefile
+$ make distclean     # to remove the all created files
+</pre>
+</blockquote>
+
+<hr>
+<h2>Functions and Classes</h2>
+
+after loading the `dl' library, we get access to the module called `DL'.
+the DL module has the following constants, functions and classes.
+
+<h2>Constants</h2>
+
+VERSION<br>
+MAJOR_VERSION<br>
+MINOR_VERSION<br>
+PATCH_VERSION<br>
+RTLD_GLOBAL<br>
+RTLD_LAZY<br>
+RTLD_NOW<br>
+MAX_ARG<br>
+MAX_CBARG<br>
+MAX_CBENT<br>
+
+<h2>Functions</h2>
+
+<dl>
+ <dt>handle = dlopen(lib){|handle| ... }</dt>
+ <dd>is quite equal to `Handle.new(lib)'
+
+ <dt>sym = set_callback(cbtype, entry){|args| ... }
+ <dt>sym = set_callback(cbtype, entry, proc)
+ <dd>makes <u>entry</u>-th pre-defined function to call the <u>proc</u>
+     or given block.
+     the <u>entry</u>-th pre-defined function is specified by
+     <u>cbtype</u> and <u>entry</u>.
+     <u>cbtype</u> is a prototype of the callback.
+     see also the section `Type specifiers' about <u>cbtype</u>.
+
+ <dt>sym = get_callback(cbtype, entry)
+ <dd>returns the Proc object which is given by the above function `set_callback'.
+
+ <dt>ptr = malloc(size, [free = nil])
+ <dd>allocates the <u>size</u> bytes, and returns the pointer as a
+     PtrData object <u>ptr</u>.
+
+ <dt>ptr = strdup(str)
+ <dd>returns a PtrData object <u>ptr</u> which represents the pointer to
+     a new string which is a duplicate of the string <u>str</u>.
+
+ <dt>size = sizeof(type)
+ <dd>returns the size of <u>type</u>. `sizeof("C") + sizeof("L")' is not
+     equal to `sizeof("CL")'. the latter is assumed to returns the
+     enough size of the structure `struct foo { char c; long l; }',
+     but the size may not equal to `sizeof(foo)' of C.
+</dl>
+
+<h2>class Handle</h2>
+
+<dl>
+ <dt>handle = Handle.new(lib){|handle| ... }</dt>
+ <dd>opens a library <u>lib</u> and returns a Handle object
+     <u>handle</u>. if a block is given, the handle is
+     automatically closed as the block ends.
+
+ <dt>Handle#close
+ <dd>closes the handle opened by the above Handle.new(lib).
+
+ <dt>sym = Handle#sym(func, prototype = "0")
+ <dt>sym = Handle#[func, prototype = nil]
+ <dd>obtains the pointer to a function called <u>func</u> and returns
+     a Symbol object or a DataPtr object.
+     <u>prototype</u> is a string which consists of type specifiers,
+     it indicates the function's prototype.
+     see also the section `Type specifiers'.
+</dl>
+
+<h2>class Symbol</h2>
+
+<dl>
+ <dt>sym = Symbol.new(addr, type = nil, name = nil)
+ <dd>creates the Symbol object <u>sym</u> with the type <u>type</u>
+     if <u>type</u> is not nil. <u>addr</u> is the address where the
+     function is allocated. If <u>type</u> is nil, it returns a DataPtr
+     object.
+
+ <dt>Symbol::char2type(char)
+ <dd>takes a character <u>char</u> that represents a type and returns
+     the type specifier of the C language.
+
+ <dt>str = Symbol#proto()
+ <dd>returns the function prototype.
+
+ <dt>str = Symbol#name()
+ <dd>Returns the function name.
+
+ <dt>str = Symbol#cproto()
+ <dt>str = Symbol#to_s()
+ <dd>returns the prototype of the C language.
+
+ <dt>str = Symbol#inspect()
+ <dd>returns the inspectable string.
+
+ <dt>r,rs = Symbol#call(arg1,arg2,...,argN)
+ <dt>r,rs = Symbol#[](arg1,arg2,...,argN)
+ <dd>calls the function with parameters arg1, arg2, ..., argN.
+     and the result consists of the return value <u>r</u> and
+     parameters <u>rs</u>. <u>rs</u> is an array.
+
+ <dt>ptr = Symbol#to_ptr
+ <dd>returns the corresponding PtrData object <u>ptr</u>.
+</dl>
+
+<h2>class PtrData</h2>
+
+<dl>
+ <dt>ptr = PtrData.new(addr, [free = nil])
+ <dd>returns the PtrData object representing the pointer which
+     indicates the address <u>addr</u>.
+     GC frees the memory using the <u>free</u> function.
+
+ <dt>PtrData#free=(sym)
+ <dd>if you specify a symbol object <u>sym</u>, GC frees the memory
+     using the function represented by <u>sym</u>.
+
+ <dt>sym = PtrData#free
+ <dd>returns a symbol object <u>sym</u> which is used when GC frees
+     the memory. it usually configured by `PtrData#free=' or `PtrData.new'.
+
+ <dt>size = PtrData#size, PtrData#size=(size)
+ <dd>gets and sets allocated size of the memory.
+
+ <dt>ary = PtrData#to_a(type, [size])
+ <dd>returns an array of the type which specified with <u>type</u>.
+     <u>type</u> must be one of 'S','P','I','L','D' and 'F'.
+
+ <dt>str = PtrData#to_s([len])
+ <dd>returns a string which length is <u>len</u>. if <u>len</u>
+     is omitted, the end of the string is '\0'.
+
+ <dt>ptr = PtrData#ptr,+@
+ <dd>returns the pointed value as a PtrData object <u>ptr</u>.
+
+ <dt>ptr = PtrData#ref,-@
+ <dd>returns the reference as a PtrData object <u>ptr</u>.
+
+ <dt>ptr = PtrData#+
+ <dd>returns the PtrData object
+
+ <dt>ptr = PtrData#-
+ <dd>returns the PtrData object
+
+ <dt>PtrData#struct!(type, *members)
+ <dd>defines the data type to get access to a structure member with a symbol.
+     (see also PtrData#[])
+
+ <dt>PtrData#union!(type, *members)
+ <dd>defines the data type to get access to a union member with a symbol.
+     (see also PtrData#[])
+
+ <dt>val = PtrData#[key], PtrData#[key, num = 0]
+ <dd>if the <u>key</u> is a string or symbol, this method returns the
+     value of the structure/union member which has the type defined by
+     PtrData#{struct!,union!}.
+     if the <u>key</u> is a integer value and this object represents
+     the pointer <u>ptr</u>, it returns the value of 
+     `(<u>ptr</u> + <u>key</u>).to_s(num)'
+
+ <dt>PtrData#[key,num]=val, PtrData#[key]=val
+ <dd>if the <u>key</u> is a string or symbol, this method substitute
+     the value of the structure/union member with <u>val</u>.
+     if the <u>key</u> is a integer value and <u>val</u> is a string,
+     this method copies <u>num</u> bytes of <u>val</u> to the memory
+     area <u>ptr</u> using memcpy(3).
+</dl>
+
+<hr>
+<h2>Type specifiers</h2>
+
+the <u>prototype</u> consists of the following type specifiers,
+first element of <u>prototype</u> represents the type of return value,
+and remaining elements represent the type of each argument.
+
+<blockquote>
+ C : a character (char)<br>
+ c : a pointer to a character (char *)<br>
+ H : a short integer (short)<br>
+ h : a pointer to a short integer (short *)<br>
+ I : an integer (char, short, int)<br>
+ i : a pointer to an integer (char *, short *, int *)<br>
+ L : a long integer (long)<br>
+ l : a pointer to a long integer (long *)<br>
+ F : a real (float)<br>
+ f : a pointer to a real (float *)<br>
+ D : a real (double)<br>
+ d : a pointer to a real (double *)<br>
+ S : an immutable string (const char *)<br>
+ s : a mutable string (char *)<br>
+ A : an array (const type[])<br>
+ a : a mutable array (type[])<br>
+ P : a pointer (void *)<br>
+ p : a mutable object (void *)<br>
+ 0 : void function
+     (this must be a first character of the <u>prototype</u>)<br>
+</blockquote>
+
+the <u>cbtype</u> consists of type specifiers 0, I, L, D and P.
+<br>
+for example:
+<blockquote>
+<pre>
+DL.set_callback('IPP',0){|ptr1,ptr2|
+  str1 = ptr1.ptr.to_s
+  str2 = ptr2.ptr.to_s
+  return str1 <=> str2
+}
+</pre>
+</blockquote>
+
+<hr>
+<i>ttate@kt.jaist.ac.jp</i>
+
+</body>
+</html>
\ No newline at end of file
diff --git a/ext/dl/depend b/ext/dl/depend
new file mode 100644
index 0000000000..50ef5cebbf
--- /dev/null
+++ b/ext/dl/depend
@@ -0,0 +1,45 @@
+RUBY = $(RUBY_INSTALL_NAME)$(EXEEXT)
+CLEANFILES = test/test.o
+DISTCLEANFILES = call.func callback.func cbtable.func dlconfig.rb dlconfig.h \
+                 test/libtest.so test/*~ *~ mkmf.log
+
+libtest.so: test/libtest.so
+
+test/libtest.so: test/test.o test/libtest.def
+	$(RUBY) -rftools -e 'ARGV.each{|d|File.mkpath(File.dirname(d))}' $@
+	`$(RUBY) -e 'print ARGV.join(" ").gsub(/dl\\.def/,"test/libtest.def")' $(LDSHARED)` $(LDFLAGS) test/test.o -o test/libtest.so
+
+test/test.o: test/test.c
+	@$(RUBY) -rftools -e 'File.mkpath(*ARGV)' test
+	$(CC) $(CFLAGS) $(CPPFLAGS) -c $< -o $@
+
+test:: dl.so libtest.so .force
+	$(RUBY) -I. -I$(srcdir)/lib $(srcdir)/test/test.rb
+
+.force:
+
+.PHONY: .force test
+
+allclean: distclean
+	@rm -f $(CLEANFILES) $(DISTCLEANFILES)
+
+$(OBJS): dlconfig.h
+
+sym.o: call.func
+
+dl.o: callback.func cbtable.func
+
+call.func: mkcall.rb dlconfig.rb
+	@echo "Generating call.func"
+	@$(RUBY) $< > $@
+
+callback.func: mkcallback.rb dlconfig.rb
+	@echo "Generating callback.func"
+	@$(RUBY) $< > $@
+
+cbtable.func: mkcbtable.rb dlconfig.rb
+	@echo "Generating cbtable.func"
+	@$(RUBY) $< > $@
+
+debug:
+	$(MAKE) CFLAGS+=-DDEBUG
diff --git a/ext/dl/dl.c b/ext/dl/dl.c
new file mode 100644
index 0000000000..b8e7381f83
--- /dev/null
+++ b/ext/dl/dl.c
@@ -0,0 +1,655 @@
+/*
+ * $Id$
+ */
+
+#include <ruby.h>
+#include <rubyio.h>
+#include "dl.h"
+
+VALUE rb_mDL;
+VALUE rb_eDLError;
+VALUE rb_eDLTypeError;
+
+static VALUE DLFuncTable;
+static void *rb_dl_func_table[MAX_CALLBACK_TYPE][MAX_CALLBACK];
+static ID id_call;
+
+#include "callback.func"
+
+static void
+init_dl_func_table(){
+#include "cbtable.func"
+};
+
+void *
+dlmalloc(size_t size)
+{
+  DEBUG_CODE2({
+    void *ptr;
+
+    printf("dlmalloc(%d)",size);
+    ptr = xmalloc(size);
+    printf(":0x%x\n",ptr);
+    return ptr;
+  },
+  {
+    return xmalloc(size);
+  });
+};
+
+void *
+dlrealloc(void *ptr, size_t size)
+{
+  DEBUG_CODE({
+    printf("dlrealloc(0x%x,%d)\n",ptr,size);
+  });
+  return xrealloc(ptr, size);
+};
+
+void
+dlfree(void *ptr)
+{
+  DEBUG_CODE({
+    printf("dlfree(0x%x)\n",ptr);
+  });
+  xfree(ptr);
+};
+
+char*
+dlstrdup(const char *str)
+{
+  char *newstr;
+
+  newstr = (char*)dlmalloc(strlen(str));
+  strcpy(newstr,str);
+
+  return newstr;
+};
+
+size_t
+dlsizeof(const char *cstr)
+{
+  size_t size;
+  int i, len, n, dlen;
+  char *d;
+
+  len  = strlen(cstr);
+  size = 0;
+  for( i=0; i<len; i++ ){
+    n = 1;
+    if( isdigit(cstr[i+1]) ){
+      dlen = 1;
+      while( isdigit(cstr[i+dlen]) ){ dlen ++; };
+      dlen --;
+      d = ALLOCA_N(char, dlen + 1);
+      strncpy(d, cstr + i + 1, dlen);
+      d[dlen] = '\0';
+      n = atoi(d);
+    }
+    else{
+      dlen = 0;
+    };
+
+    switch( cstr[i] ){
+    case 'I':
+      DLALIGN(0,size,INT_ALIGN);
+    case 'i':
+      size += sizeof(int) * n;
+      break;
+    case 'L':
+      DLALIGN(0,size,LONG_ALIGN);
+    case 'l':
+      size += sizeof(long) * n;
+      break;
+    case 'F':
+      DLALIGN(0,size,FLOAT_ALIGN);
+    case 'f':
+      size += sizeof(float) * n;
+      break;
+    case 'D':
+      DLALIGN(0,size,DOUBLE_ALIGN);
+    case 'd':
+      size += sizeof(double) * n;
+      break;
+    case 'C':
+    case 'c':
+      size += sizeof(char) * n;
+      break;
+    case 'H':
+      DLALIGN(0,size,SHORT_ALIGN);
+    case 'h':
+      size += sizeof(short) * n;
+      break;
+    case 'P':
+      DLALIGN(0,size,VOIDP_ALIGN);
+    case 'p':
+      size += sizeof(void*) * n;
+      break;
+    default:
+      rb_raise(rb_eDLTypeError, "unexpected type '%c'", cstr[i]);
+      break;
+    };
+    i += dlen;
+  };
+
+  return size;
+};
+
+static float *
+c_farray(VALUE v, long *size)
+{
+  int i, len;
+  float *ary;
+  VALUE e;
+
+  len = RARRAY(v)->len;
+  *size = sizeof(float) * len;
+  ary = dlmalloc(*size);
+  for( i=0; i < len; i++ ){
+    e = rb_ary_entry(v, i);
+    switch( TYPE(e) ){
+    case T_FLOAT:
+      ary[i] = (float)(RFLOAT(e)->value);
+      break;
+    case T_NIL:
+      ary[i] = 0.0;
+      break;
+    default:
+      rb_raise(rb_eDLTypeError, "unexpected type of the element #%d", i);
+      break;
+    };
+  };
+
+  return ary;
+};
+
+static double *
+c_darray(VALUE v, long *size)
+{
+  int i, len;
+  double *ary;
+  VALUE e;
+
+  len = RARRAY(v)->len;
+  *size = sizeof(double) * len;
+  ary = dlmalloc(*size);
+  for( i=0; i < len; i++ ){
+    e = rb_ary_entry(v, i);
+    switch( TYPE(e) ){
+    case T_FLOAT:
+      ary[i] = (double)(RFLOAT(e)->value);
+      break;
+    case T_NIL:
+      ary[i] = 0.0;
+      break;
+    default:
+      rb_raise(rb_eDLTypeError, "unexpected type of the element #%d", i);
+      break;
+    };
+  };
+
+  return ary;
+};
+
+static long *
+c_larray(VALUE v, long *size)
+{
+  int i, len;
+  long *ary;
+  VALUE e;
+
+  len = RARRAY(v)->len;
+  *size = sizeof(long) * len;
+  ary = dlmalloc(*size);
+  for( i=0; i < len; i++ ){
+    e = rb_ary_entry(v, i);
+    switch( TYPE(e) ){
+    case T_FIXNUM:
+    case T_BIGNUM:
+      ary[i] = (long)(NUM2INT(e));
+      break;
+    case T_NIL:
+      ary[i] = 0;
+      break;
+    default:
+      rb_raise(rb_eDLTypeError, "unexpected type of the element #%d", i);
+      break;
+    };
+  };
+
+  return ary;
+};
+
+static int *
+c_iarray(VALUE v, long *size)
+{
+  int i, len;
+  int *ary;
+  VALUE e;
+
+  len = RARRAY(v)->len;
+  *size = sizeof(int) * len;
+  ary = dlmalloc(*size);
+  for( i=0; i < len; i++ ){
+    e = rb_ary_entry(v, i);
+    switch( TYPE(e) ){
+    case T_FIXNUM:
+    case T_BIGNUM:
+      ary[i] = (int)(NUM2INT(e));
+      break;
+    case T_NIL:
+      ary[i] = 0;
+      break;
+    default:
+      rb_raise(rb_eDLTypeError, "unexpected type of the element #%d", i);
+      break;
+    };
+  };
+
+  return ary;
+};
+
+static short *
+c_harray(VALUE v, long *size)
+{
+  int i, len;
+  short *ary;
+  VALUE e;
+
+  len = RARRAY(v)->len;
+  *size = sizeof(short) * len;
+  ary = dlmalloc(*size);
+  for( i=0; i < len; i++ ){
+    e = rb_ary_entry(v, i);
+    switch( TYPE(e) ){
+    case T_FIXNUM:
+    case T_BIGNUM:
+      ary[i] = (short)(NUM2INT(e));
+      break;
+    case T_NIL:
+      ary[i] = 0;
+      break;
+    default:
+      rb_raise(rb_eDLTypeError, "unexpected type of the element #%d", i);
+      break;
+    };
+  };
+
+  return ary;
+};
+
+static char *
+c_carray(VALUE v, long *size)
+{
+  int i, len;
+  char *ary;
+  VALUE e;
+
+  len = RARRAY(v)->len;
+  *size = sizeof(char) * len;
+  ary = dlmalloc(*size);
+  for( i=0; i < len; i++ ){
+    e = rb_ary_entry(v, i);
+    switch( TYPE(e) ){
+    case T_FIXNUM:
+    case T_BIGNUM:
+      ary[i] = (char)(NUM2INT(e));
+      break;
+    case T_NIL:
+      ary[i] = 0;
+      break;
+    default:
+      rb_raise(rb_eDLTypeError, "unexpected type of the element #%d", i);
+      break;
+    };
+  };
+
+  return ary;
+};
+
+static void *
+c_parray(VALUE v, long *size)
+{
+  int i, len;
+  void **ary;
+  VALUE e;
+
+  len = RARRAY(v)->len;
+  *size = sizeof(void*) * len;
+  ary = dlmalloc(*size);
+  for( i=0; i < len; i++ ){
+    e = rb_ary_entry(v, i);
+    switch( TYPE(e) ){
+    case T_STRING:
+      {
+	char *str, *src;
+	src = STR2CSTR(e);
+	str = dlstrdup(src);
+	ary[i] = (void*)str;
+      };
+      break;
+    case T_NIL:
+      ary[i] = NULL;
+      break;
+    case T_DATA:
+      if( rb_obj_is_kind_of(e, rb_cDLPtrData) ){
+	struct ptr_data *pdata;
+	Data_Get_Struct(e, struct ptr_data, pdata);
+	ary[i] = (void*)(pdata->ptr);
+      }
+      else{
+	rb_raise(rb_eDLTypeError, "unexpected type of the element #%d", i);
+      };
+      break;
+    default:
+      rb_raise(rb_eDLTypeError, "unexpected type of the element #%d", i);
+      break;
+    };
+  };
+
+  return ary;
+};
+
+void *
+rb_ary2cary(char t, VALUE v, long *size)
+{
+  int len;
+  VALUE val0;
+
+  if( TYPE(v) != T_ARRAY ){
+    rb_raise(rb_eDLTypeError, "an array is expected.");
+  };
+
+  len = RARRAY(v)->len;
+  if( len == 0 ){
+    return NULL;
+  };
+
+  if( !size ){
+    size = ALLOCA_N(long,1);
+  };
+
+  val0 = rb_ary_entry(v,0);
+  switch( TYPE(val0) ){
+  case T_FIXNUM:
+  case T_BIGNUM:
+    switch( t ){
+    case 'C': case 'c':
+      return (void*)c_carray(v,size);
+    case 'H': case 'h':
+      return (void*)c_harray(v,size);
+    case 'I': case 'i':
+      return (void*)c_iarray(v,size);
+    case 'L': case 'l': case 0:
+      return (void*)c_larray(v,size);
+    default:
+      rb_raise(rb_eDLTypeError, "type mismatch");
+    };
+  case T_STRING:
+    return (void*)c_parray(v,size);
+  case T_FLOAT:
+    switch( t ){
+    case 'F': case 'f':
+      return (void*)c_farray(v,size);
+    case 'D': case 'd': case 0:
+      return (void*)c_darray(v,size);
+    };
+    rb_raise(rb_eDLTypeError, "type mismatch");
+  case T_DATA:
+    if( rb_obj_is_kind_of(val0, rb_cDLPtrData) ){
+      return (void*)c_parray(v,size);
+    };
+    rb_raise(rb_eDLTypeError, "type mismatch");
+  default:
+    rb_raise(rb_eDLTypeError, "unsupported type");
+  };
+};
+
+VALUE
+rb_str_to_ptr(VALUE self)
+{
+  char *ptr;
+  int  len;
+
+  len = RSTRING(self)->len;
+  ptr = (char*)dlmalloc(len + 1);
+  memcpy(ptr, STR2CSTR(self), len);
+  ptr[len] = '\0';
+  return rb_dlptr_new((void*)ptr,len,dlfree);
+};
+
+VALUE
+rb_ary_to_ptr(int argc, VALUE argv[], VALUE self)
+{
+  void *ptr;
+  VALUE t;
+  long size;
+
+  switch( rb_scan_args(argc, argv, "01", &t) ){
+  case 1:
+    ptr = rb_ary2cary(STR2CSTR(t)[0], self, &size);
+    break;
+  case 0:
+    ptr = rb_ary2cary(0, self, &size);
+    break;
+  };
+  return ptr ? rb_dlptr_new(ptr, size, dlfree) : Qnil;
+};
+
+VALUE
+rb_io_to_ptr(VALUE self)
+{
+  OpenFile *fptr;
+  FILE     *fp;
+
+  GetOpenFile(self, fptr);
+  fp = fptr->f;
+
+  return fp ? rb_dlptr_new(fp, sizeof(FILE), 0) : Qnil;
+};
+
+VALUE
+rb_dl_dlopen(int argc, VALUE argv[], VALUE self)
+{
+  return rb_dlhandle_s_new(argc, argv, rb_cDLHandle);
+};
+
+VALUE
+rb_dl_malloc(VALUE self, VALUE size)
+{
+  void *ptr;
+  long s;
+
+  s = DLNUM2LONG(size);
+  ptr = dlmalloc((size_t)s);
+  memset(ptr,0,(size_t)s);
+  return rb_dlptr_new(ptr, s, dlfree);
+};
+
+VALUE
+rb_dl_strdup(VALUE self, VALUE str)
+{
+  void *p;
+
+  str = rb_String(str);
+  return rb_dlptr_new(strdup(STR2CSTR(str)), RSTRING(str)->len, dlfree);
+};
+
+static VALUE
+rb_dl_sizeof(VALUE self, VALUE str)
+{
+  return INT2NUM(dlsizeof(STR2CSTR(str)));
+};
+
+static VALUE
+rb_dl_callback_type(VALUE str)
+{
+  char *type;
+  int len;
+  int i;
+  long ftype;
+
+  ftype = 0;
+  type = STR2CSTR(str);
+  len  = RSTRING(str)->len;
+
+  if( len - 1 > MAX_CBARG ){
+    rb_raise(rb_eDLError, "maximum number of the argument is %d.", MAX_CBARG);
+  };
+
+  for( i = len - 1; i > 0; i-- ){
+    switch( type[i] ){
+    case 'P':
+      CBPUSH_P(ftype);
+      break;
+    case 'I':
+      CBPUSH_I(ftype);
+      break;
+    case 'L':
+      CBPUSH_L(ftype);
+      break;
+    case 'F':
+      CBPUSH_F(ftype);
+      break;
+    case 'D':
+      CBPUSH_D(ftype);
+    default:
+      rb_raise(rb_eDLError, "unsupported type `%c'", type[i]);
+      break;
+    };
+  };
+
+  switch( type[0] ){
+  case '0':
+    CBPUSH_0(ftype);
+    break;
+  case 'P':
+    CBPUSH_P(ftype);
+    break;
+  case 'I':
+    CBPUSH_I(ftype);
+    break;
+  case 'L':
+    CBPUSH_L(ftype);
+    break;
+  case 'F':
+    CBPUSH_F(ftype);
+    break;
+  case 'D':
+    CBPUSH_D(ftype);
+    break;
+  default:
+    rb_raise(rb_eDLError, "unsupported type `%c'", type[i]);
+    break;
+  };
+
+  return INT2NUM(ftype);
+};
+
+VALUE
+rb_dl_set_callback(int argc, VALUE argv[], VALUE self)
+{
+  VALUE types, num, proc;
+  VALUE key;
+  VALUE entry;
+  void *func;
+
+  char func_name[1024];
+  extern dln_sym();
+
+  switch( rb_scan_args(argc, argv, "21", &types, &num, &proc) ){
+  case 2:
+    proc = rb_f_lambda();
+    break;
+  case 3:
+    break;
+  default:
+    rb_bug("rb_dl_set_callback");
+  };
+
+  key = rb_dl_callback_type(types);
+  entry = rb_hash_aref(DLFuncTable, key);
+  if( entry == Qnil ){
+    entry = rb_hash_new();
+    rb_hash_aset(DLFuncTable, key, entry);
+  };
+
+  func = rb_dl_func_table[NUM2INT(key)][NUM2INT(num)];
+  if( func ){
+    rb_hash_aset(entry, num, proc);
+    snprintf(func_name, 1023, "rb_dl_func%d_%d", NUM2INT(key), NUM2INT(num));
+    return rb_dlsym_new(func, func_name, STR2CSTR(types));
+  }
+  else{
+    return Qnil;
+  };
+};
+
+VALUE
+rb_dl_get_callback(VALUE self, VALUE types, VALUE num)
+{
+  VALUE key;
+  VALUE entry;
+
+  key = rb_dl_callback_type(types);
+  entry = rb_hash_aref(DLFuncTable, key);
+  if( entry == Qnil ){
+    return Qnil;
+  };
+  return rb_hash_aref(entry, num);
+};
+
+void
+Init_dl()
+{
+  void Init_dlptr();
+  void Init_dlsym();
+  void Init_dlhandle();
+
+  id_call = rb_intern("call");
+
+  rb_mDL = rb_define_module("DL");
+
+  rb_eDLError = rb_define_class_under(rb_mDL, "DLError", rb_eStandardError);
+  rb_eDLTypeError = rb_define_class_under(rb_mDL, "DLTypeError", rb_eDLError);
+
+  DLFuncTable = rb_hash_new();
+  init_dl_func_table();
+  rb_define_const(rb_mDL, "FuncTable", DLFuncTable);
+
+  rb_define_const(rb_mDL, "RTLD_GLOBAL", INT2NUM(RTLD_GLOBAL));
+  rb_define_const(rb_mDL, "RTLD_LAZY",   INT2NUM(RTLD_LAZY));
+  rb_define_const(rb_mDL, "RTLD_NOW",    INT2NUM(RTLD_NOW));
+
+  rb_define_const(rb_mDL, "ALIGN_INT",   INT2NUM(ALIGN_INT));
+  rb_define_const(rb_mDL, "ALIGN_LONG",  INT2NUM(ALIGN_LONG));
+  rb_define_const(rb_mDL, "ALIGN_FLOAT", INT2NUM(ALIGN_FLOAT));
+  rb_define_const(rb_mDL, "ALIGN_SHORT", INT2NUM(ALIGN_SHORT));
+  rb_define_const(rb_mDL, "ALIGN_DOUBLE",INT2NUM(ALIGN_DOUBLE));
+  rb_define_const(rb_mDL, "ALIGN_VOIDP", INT2NUM(ALIGN_VOIDP));
+
+  rb_define_const(rb_mDL, "VERSION",     rb_tainted_str_new2(DL_VERSION));
+  rb_define_const(rb_mDL, "MAJOR_VERSION", INT2NUM(DL_MAJOR_VERSION));
+  rb_define_const(rb_mDL, "MINOR_VERSION", INT2NUM(DL_MINOR_VERSION));
+  rb_define_const(rb_mDL, "PATCH_VERSION", INT2NUM(DL_PATCH_VERSION));
+  rb_define_const(rb_mDL, "MAX_ARG", INT2NUM(MAX_ARG));
+  rb_define_const(rb_mDL, "MAX_CBARG", INT2NUM(MAX_CBARG));
+  rb_define_const(rb_mDL, "MAX_CBENT", INT2NUM(MAX_CBENT));
+
+  rb_define_module_function(rb_mDL, "dlopen", rb_dl_dlopen, -1);
+  rb_define_module_function(rb_mDL, "set_callback", rb_dl_set_callback, -1);
+  rb_define_module_function(rb_mDL, "get_callback", rb_dl_get_callback, 2);
+  rb_define_module_function(rb_mDL, "malloc", rb_dl_malloc, 1);
+  rb_define_module_function(rb_mDL, "strdup", rb_dl_strdup, 1);
+  rb_define_module_function(rb_mDL, "sizeof", rb_dl_sizeof, 1);
+
+  Init_dlptr();
+  Init_dlsym();
+  Init_dlhandle();
+
+  rb_define_const(rb_mDL, "FREE", rb_dlsym_new(dlfree, "free", "0P"));
+
+  rb_define_method(rb_cString, "to_ptr", rb_str_to_ptr, 0);
+  rb_define_method(rb_cArray, "to_ptr", rb_ary_to_ptr, -1);
+  rb_define_method(rb_cIO, "to_ptr", rb_io_to_ptr, 0);
+};
diff --git a/ext/dl/dl.def b/ext/dl/dl.def
new file mode 100644
index 0000000000..75da180a7a
--- /dev/null
+++ b/ext/dl/dl.def
@@ -0,0 +1,70 @@
+EXPORTS
+Init_dl
+dlfree
+dlmalloc
+dlrealloc
+dlstrdup
+rb_ary2cary
+rb_ary_to_ptr
+rb_dl_dlopen
+rb_dl_get_callback
+rb_dl_malloc
+rb_dl_set_callback
+rb_dl_strdup
+rb_eDLError
+rb_eDLTypeError
+rb_io_to_ptr
+rb_mDL
+rb_str_to_ptr
+Init_dlhandle
+dlhandle_free
+rb_cDLHandle
+rb_dlhandle_close
+rb_dlhandle_disable_close
+rb_dlhandle_enable_close
+rb_dlhandle_init
+rb_dlhandle_s_new
+rb_dlhandle_sym
+Init_dlptr
+dlptr_free
+dlptr_init
+rb_cDLPtrData
+rb_dlmem_each
+rb_dlptr2cptr
+rb_dlptr_alloc
+rb_dlptr_aref
+rb_dlptr_aset
+rb_dlptr_cmp
+rb_dlptr_define_data_type
+rb_dlptr_define_struct
+rb_dlptr_define_union
+rb_dlptr_eql
+rb_dlptr_free_get
+rb_dlptr_free_set
+rb_dlptr_get_data_type
+rb_dlptr_inspect
+rb_dlptr_minus
+rb_dlptr_new
+rb_dlptr_null_p
+rb_dlptr_plus
+rb_dlptr_ptr
+rb_dlptr_ref
+rb_dlptr_to_array
+rb_dlptr_to_i
+rb_dlptr_to_s
+rb_dlptr_to_str
+rb_mDLMemorySpace
+Init_dlsym
+dlsym_free
+rb_cDLSymbol
+rb_dlsym2csym
+rb_dlsym_call
+rb_dlsym_cproto
+rb_dlsym_initialize
+rb_dlsym_inspect
+rb_dlsym_name
+rb_dlsym_new
+rb_dlsym_proto
+rb_dlsym_s_new
+rb_dlsym_to_ptr
+rb_s_dlsym_char2type
diff --git a/ext/dl/dl.h b/ext/dl/dl.h
new file mode 100644
index 0000000000..27290fc12b
--- /dev/null
+++ b/ext/dl/dl.h
@@ -0,0 +1,282 @@
+/* -*- C -*-
+ * $Id$
+ */
+
+#ifndef RUBY_DL_H
+#define RUBY_DL_H
+
+#include <ruby.h>
+#include <dlconfig.h>
+
+#if defined(HAVE_DLFCN_H)
+# include <dlfcn.h>
+#else
+# if defined(HAVE_WINDOWS_H)
+#   include <windows.h>
+#   define dlclose(ptr) FreeLibrary((HINSTANCE)ptr)
+#   define dlopen(name,flag) ((void*)LoadLibrary(name))
+#   define dlerror()    "unknown error"
+#   define dlsym(handle,name) ((void*)GetProcAddress(handle,name))
+#   define RTLD_LAZY -1
+#   define RTLD_NOW  -1
+#   define RTLD_GLOBAL -1
+# endif
+#endif
+
+#ifdef DEBUG
+#define DEBUG_CODE(b) {printf("DEBUG:%d\n",__LINE__);b;}
+#define DEBUG_CODE2(b1,b2) {printf("DEBUG:%d\n",__LINE__);b1;}
+#else
+#define DEBUG_CODE(b)
+#define DEBUG_CODE2(b1,b2) b2
+#endif
+
+#define DL_VERSION     "1.1.0"
+#define DL_MAJOR_VERSION 1
+#define DL_MINOR_VERSION 1
+#define DL_PATCH_VERSION 0
+
+#define VOID_DLTYPE   0x00
+#define CHAR_DLTYPE   0x01
+#define SHORT_DLTYPE  0x02
+#define INT_DLTYPE    0x03
+#define LONG_DLTYPE   0x04
+#define FLOAT_DLTYPE  0x05
+#define DOUBLE_DLTYPE 0x06
+#define VOIDP_DLTYPE  0x07
+
+#define ARG_TYPE(x,i) (((x) & (0x07 << ((i)*3))) >> ((i)*3))
+#define PUSH_ARG(x,t) do{x <<= 3; x |= t;}while(0)
+#define PUSH_0(x) PUSH_ARG(x,VOID_DLTYPE)
+
+#if SIZEOF_INT == SIZEOF_LONG
+# define PUSH_I(x) PUSH_ARG(x,LONG_DLTYPE)
+# define ANY2I(x)  x.l
+# define DLINT(x)  (long)x
+#else
+# define PUSH_I(x) PUSH_ARG(x,INT_DLTYPE)
+# define ANY2I(x)  x.i
+# define DLINT(x)  (int)x
+#endif
+#define PUSH_L(x) PUSH_ARG(x,LONG_DLTYPE)
+#define ANY2L(x)  x.l
+#define DLLONG(x) (long)x
+
+#if defined(WITH_TYPE_FLOAT)
+# if SIZEOF_FLOAT == SIZEOF_DOUBLE
+#   define PUSH_F(x) PUSH_ARG(x,DOUBLE_DLTYPE)
+#   define ANY2F(x)  (x.d)
+#   define DLFLOAT(x) ((double)x)
+# else
+#   define PUSH_F(x) PUSH_ARG(x,FLOAT_DLTYPE)
+#   define ANY2F(x)  (x.f)
+#   define DLFLOAT(x) ((float)x)
+# endif
+#else
+# define PUSH_F(x) PUSH_ARG(x,DOUBLE_DLTYPE)
+# define ANY2F(x)  (x.d)
+# define DLFLOAT(x) ((double)x)
+#endif
+#define PUSH_D(x) PUSH_ARG(x,DOUBLE_DLTYPE)
+#define ANY2D(x)  (x.d)
+#define DLDOUBLE(x) ((double)x)
+
+#if SIZEOF_INT == SIZEOF_VOIDP && SIZEOF_INT != SIZEOF_LONG
+# define PUSH_P(x) PUSH_ARG(x,INT_DLTYPE)
+# define ANY2P(x)  (x.i)
+# define DLVOIDP(x) ((int)x)
+#elif SIZEOF_LONG == SIZEOF_VOIDP
+# define PUSH_P(x) PUSH_ARG(x,LONG_DLTYPE)
+# define ANY2P(x)  (x.l)
+# define DLVOIDP(x) ((long)x)
+#else
+# define PUSH_P(x) PUSH_ARG(x,VOIDP_DLTYPE)
+# define ANY2P(x)  (x.p)
+# define DLVOIDP(x) ((void*)p)
+#endif
+
+#if defined(WITH_TYPE_CHAR)
+# define PUSH_C(x) PUSH_ARG(x,CHAR_DLTYPE)
+# define ANY2C(x)  (x.c)
+# define DLCHAR(x) ((char)x)
+#else
+# define PUSH_C(x) PUSH_I(x)
+# define ANY2C(x)  ANY2I(x)
+# define DLCHAR(x) DLINT(x)
+#endif
+
+#if defined(WITH_TYPE_SHORT)
+# define PUSH_H(x) PUSH_ARG(x,SHORT_DLTYPE)
+# define ANY2H(x)  (x.h)
+# define DLSHORT(x) ((short)x)
+#else
+# define PUSH_H(x) PUSH_I(x)
+# define ANY2H(x)  ANY2I(x)
+# define DLSHORT(x) DLINT(x)
+#endif
+
+#define PUSH_S(x) PUSH_P(x)
+#define ANY2S(x) ANY2P(x)
+#define DLSTR(x) DLVOIDP(x)
+
+#define CBPUSH_0(x) PUSH_0(x)
+#define CBPUSH_C(x) PUSH_C(x)
+#define CBPUSH_H(x) PUSH_H(x)
+#define CBPUSH_I(x) PUSH_I(x)
+#define CBPUSH_L(x) PUSH_L(x)
+#define CBPUSH_F(x) PUSH_F(x)
+#define CBPUSH_D(x) PUSH_D(x)
+#if defined(WITH_CBTYPE_VOIDP)
+# define CBPUSH_P(x) PUSH_ARG(x,VOIDP_DLTYPE)
+#else
+# define CBPUSH_P(x) PUSH_P(x)
+#endif
+
+
+#if defined(USE_INLINE_ASM)
+# if defined(__i386__) && defined(__GNUC__)
+#   define ASM_START(type)
+#   define ASM_END(type)
+#   define ASM_PUSH_C(x) asm volatile ("pushl %0" :: "g" (x));
+#   define ASM_PUSH_H(x) asm volatile ("pushl %0" :: "g" (x));
+#   define ASM_PUSH_I(x) asm volatile ("pushl %0" :: "g" (x));
+#   define ASM_PUSH_L(x) asm volatile ("pushl %0" :: "g" (x));
+#   define ASM_PUSH_P(x) asm volatile ("pushl %0" :: "g" (x));
+#   define ASM_PUSH_F(x) asm volatile ("flds %0"::"g"(x));\
+                         asm volatile ("subl $4,%esp");\
+                         asm volatile ("fstps (%esp)");
+#   define ASM_PUSH_D(x) asm volatile ("fldl %0"::"g"(x));\
+                         asm volatile ("subl $8,%esp");\
+                         asm volatile ("fstpl (%esp)")
+# else
+# error --with-asm is not supported on this machine
+# endif
+#else
+# define ASM_START(type)
+# define ASM_END(type)
+# define ASM_PUSH_C(x)
+# define ASM_PUSH_I(x)
+# define ASM_PUSH_L(x)
+# define ASM_PUSH_P(x)
+# define ASM_PUSH_F(x)
+# define ASM_PUSH_D(x)
+#endif
+
+extern VALUE rb_mDL;
+extern VALUE rb_mDLMemorySpace;
+extern VALUE rb_cDLHandle;
+extern VALUE rb_cDLSymbol;
+extern VALUE rb_cDLPtrData;
+extern VALUE rb_cDLStructData;
+
+extern VALUE rb_eDLError;
+extern VALUE rb_eDLTypeError;
+
+#if defined(LONG2NUM) && (SIZEOF_LONG == SIZEOF_VOIDP)
+# define DLLONG2NUM(x) LONG2NUM((long)x)
+# define DLNUM2LONG(x) (long)(NUM2LONG(x))
+#else
+# define DLLONG2NUM(x) INT2NUM((long)x)
+# define DLNUM2LONG(x) (long)(NUM2INT(x))
+#endif
+
+typedef struct { char c; void *x; } s_voidp;
+typedef struct { char c; short x; } s_short;
+typedef struct { char c; int x; } s_int;
+typedef struct { char c; long x; } s_long;
+typedef struct { char c; float x; } s_float;
+typedef struct { char c; double x; } s_double;
+
+#define ALIGN_VOIDP  (sizeof(s_voidp) - sizeof(void *))
+#define ALIGN_SHORT  (sizeof(s_short) - sizeof(short))
+#define ALIGN_INT    (sizeof(s_int) - sizeof(int))
+#define ALIGN_LONG   (sizeof(s_long) - sizeof(long))
+#define ALIGN_FLOAT  (sizeof(s_float) - sizeof(float))
+#define ALIGN_DOUBLE (sizeof(s_double) - sizeof(double))
+
+/* for compatibility */
+#define VOIDP_ALIGN  ALIGN_VOIDP
+#define SHORT_ALIGN  ALIGN_SHORT
+#define INT_ALIGN    ALIGN_INT
+#define LONG_ALIGN   ALIGN_LONG
+#define FLOAT_ALIGN  ALIGN_FLOAT
+#define DOUBLE_ALIGN ALIGN_DOUBLE
+
+#define DLALIGN(ptr,offset,align) {\
+  while( (((unsigned long)(ptr + offset)) % align) != 0 ) offset++;\
+}
+
+typedef void (*freefunc_t)(void *);
+#define DLFREEFUNC(func) ((freefunc_t)(func))
+
+typedef union {
+  void*  p;
+  char   c;
+  short  h;
+  int    i;
+  long   l;
+  float  f;
+  double d;
+  char  *s;
+} ANY_TYPE;
+
+struct dl_handle {
+  void *ptr;
+  int  open;
+  int  enable_close;
+};
+
+struct sym_data {
+  void *func;
+  char *name;
+  char *type;
+  int  len;
+};
+
+enum DLPTR_CTYPE {
+  DLPTR_CTYPE_UNKNOWN,
+  DLPTR_CTYPE_STRUCT,
+  DLPTR_CTYPE_UNION
+};
+
+struct ptr_data {
+  void *ptr;       /* a pointer to the data */
+  freefunc_t free; /* free() */
+  char *stype;      /* array of type specifiers */
+  int  *ssize;      /* size[i] = sizeof(type[i]) > 0 */
+  int  slen;   /* the number of type specifiers */
+  ID   *ids;
+  int  ids_num;
+  int  ctype; /* DLPTR_CTYPE_UNKNOWN, DLPTR_CTYPE_STRUCT, DLPTR_CTYPE_UNION */
+  long size;
+};
+
+#define RDLPTR(obj)  ((struct ptr_data *)(DATA_PTR(obj)))
+#define RDLSYM(obj)  ((struct sym_data *)(DATA_PTR(obj)))
+
+void dlfree(void*);
+void *dlmalloc(size_t);
+void *dlrealloc(void*,size_t);
+char *dlstrdup(const char *);
+size_t dlsizeof(const char *);
+
+void *rb_ary2cary(char t, VALUE ary, long *size);
+
+/*
+void rb_dlmem_delete(void *ptr);
+void rb_dlmem_aset(void *ptr, VALUE obj);
+VALUE rb_dlmem_aref(void *ptr);
+*/
+
+void dlptr_free(struct ptr_data *data);
+void dlptr_init(VALUE val);
+
+VALUE rb_dlptr_new(void *ptr, long size, freefunc_t func);
+VALUE rb_dlptr_alloc(long size, freefunc_t func);
+void *rb_dlptr2cptr(VALUE val);
+
+VALUE rb_dlsym_new(void (*func)(), const char *name, const char *type);
+freefunc_t rb_dlsym2csym(VALUE val);
+
+
+#endif /* RUBY_DL_H */
diff --git a/ext/dl/extconf.rb b/ext/dl/extconf.rb
new file mode 100644
index 0000000000..372f1b1384
--- /dev/null
+++ b/ext/dl/extconf.rb
@@ -0,0 +1,197 @@
+require 'mkmf'
+$:.unshift File.dirname(__FILE__)
+require 'type'
+
+if( ARGV.include?("--help") )
+  print <<EOF
+  --help             print this messages
+  --with-type-char   strictly use type 'char'
+  --with-type-short  strictly use type 'short'
+  --with-type-float  strictly use type 'float'
+  --with-asm         use the embedded assembler for passing arguments.
+                     (this option is available for i386 machine now.)
+  --with-args=<max_arg>,<max_cbarg>,<max_cbent>
+                     <max_arg>:   maximum number of arguments of the function
+                     <max_cbarg>: maximum number of arguments of the callback
+                     <max_cbent>: maximum number of callback entries
+EOF
+  exit(0)
+end
+
+($CPPFLAGS || $CFLAGS) << " -I."
+
+case RUBY_PLATFORM  # from Win32API
+when /cygwin/,/mingw/
+  $CFLAGS << " -fno-defer-pop -fno-omit-frame-pointer"
+end
+
+if (Config::CONFIG['CC'] =~ /gcc/) && (Config::CONFIG['arch'] =~ /i.86/)
+  $with_asm = true
+else
+  $with_asm = false
+end
+
+$with_type_int = try_run(<<EOF)
+int main(){ return sizeof(int) == sizeof(long); }
+EOF
+
+$with_type_float = try_run(<<EOF)
+int main(){ return sizeof(float) == sizeof(double); }
+EOF
+
+$with_type_voidp = try_run(<<EOF)
+int main(){
+  return (sizeof(void *) == sizeof(long))
+         || (sizeof(void *) == sizeof(int));
+}
+EOF
+
+$with_type_char  = DLTYPE[CHAR][:sym]
+$with_type_short = DLTYPE[SHORT][:sym]
+$with_type_long  = DLTYPE[LONG][:sym]
+$with_type_double= DLTYPE[DOUBLE][:sym]
+$with_type_int   &= DLTYPE[INT][:sym]
+$with_type_float &= DLTYPE[FLOAT][:sym]
+$with_type_voidp &= DLTYPE[VOIDP][:sym]
+
+$with_cbtype_voidp = DLTYPE[VOIDP][:cb]
+
+$with_type_char  = with_config("type-char")  ? true : false
+$with_type_short = with_config("type-short") ? true : false 
+$with_type_float = with_config("type-float") ? true : false
+
+$with_asm        = with_config("asm") ? true : $with_asm
+
+args = with_config("args")
+max_arg = max_cbarg = max_cbent = nil
+if( $with_asm )
+  $with_type_char = true
+  $with_type_short = true
+  $with_type_float = true
+  max_arg = 0
+end
+if( args )
+  max_arg,max_cbarg,max_cbent = args.split(",").collect{|c| c.to_i}
+  if( !(max_arg && max_cbarg && max_cbent) )
+    print("--with-args=<max_arg>,<max_cbarg>,<max_cbent>\n")
+    exit(1)
+  end
+end
+max_arg   ||= 6
+max_cbarg ||= 3
+max_cbent ||= 3
+
+max_callback_type = types2num(DLTYPE.keys.sort[-1,1] * (max_cbarg + 1)) + 1
+max_callback      = max_cbent
+
+#m = [1].pack("i")
+#c,cs = m.unpack("c")
+#bigendian = (c == 0)
+#print("bigendian ... #{bigendian ? 'true' : 'false'}\n")
+
+
+$dlconfig_h = <<EOF
+#define MAX_ARG   #{max_arg}
+#define MAX_CBARG #{max_cbarg}
+#define MAX_CBENT #{max_cbent}
+#define MAX_CALLBACK_TYPE #{max_callback_type}
+#define MAX_CALLBACK      #{max_callback}
+EOF
+
+def dlc_define(const)
+  $dlconfig_h << "#if !defined(#{const})\n" +
+                 "# define #{const}\n" +
+                 "#endif\n"
+end
+
+if( $with_asm )
+  $dlconfig_h << "#define USE_INLINE_ASM\n"
+end
+if( $with_type_char )
+  $dlconfig_h << "#define WITH_TYPE_CHAR\n"
+end
+if( $with_type_short )
+  $dlconfig_h << "#define WITH_TYPE_SHORT\n"
+end
+if( $with_type_long )
+  $dlconfig_h << "#define WITH_TYPE_LONG\n"
+end
+if( $with_type_double )
+  $dlconfig_h << "#define WITH_TYPE_DOUBLE\n"
+end
+if( $with_type_float )
+  $dlconfig_h << "#define WITH_TYPE_FLOAT\n"
+end
+if( $with_type_int )
+  $dlconfig_h << "#define WITH_TYPE_INT\n"
+end
+if( $with_type_voidp )
+  $dlconfig_h << "#define WITH_TYPE_VOIDP\n"
+end
+if( $with_cbtype_voidp )
+  $dlconfig_h << "#define WITH_CBTYPE_VOIDP\n"
+end
+#if( bigendian )
+#  $dlconfig_h << "#define BIGENDIAN"
+#else
+#  $dlconfig_h << "#define LITTLEENDIAN"
+#end
+
+
+if( have_header("dlfcn.h") )
+  dlc_define("HAVE_DLFCN_H")
+  have_library("dl")
+  have_func("dlopen")
+  have_func("dlclose")
+  have_func("dlsym")
+  if( have_func("dlerror") )
+    dlc_define("HAVE_DLERROR")
+  end
+elsif( have_header("windows.h") )
+  dlc_define("HAVE_WINDOWS_H")
+  have_func("LoadLibrary")
+  have_func("FreeLibrary")
+  have_func("GetProcAddress")
+else
+  exit(0)
+end
+
+method(:have_func).arity == 1 or have_func("rb_str_cat2", "ruby.h")
+if method(:have_func).arity == 1 or !have_func("rb_block_given_p", "ruby.h")
+    $dlconfig_h << "#define rb_block_given_p rb_iterator_p\n"
+end
+
+def File.update(file, str)
+  begin
+    open(file){|f|f.read} == str
+  rescue Errno::ENOENT
+    false
+  end or open(file, "w"){|f|f.print(str)}
+end
+
+File.update("dlconfig.h", <<EOF)
+#ifndef DLCONFIG_H
+#define DLCONFIG_H
+#{$dlconfig_h}
+#endif /* DLCONFIG_H */
+EOF
+
+File.update("dlconfig.rb", <<EOF)
+MAX_ARG = #{max_arg}
+MAX_CBARG = #{max_cbarg}
+MAX_CBENT = #{max_cbent}
+DLTYPE[CHAR][:sym]  = #{$with_type_char}
+DLTYPE[SHORT][:sym] = #{$with_type_short}
+DLTYPE[INT][:sym]   = #{$with_type_int}
+DLTYPE[LONG][:sym]  = #{$with_type_long}
+DLTYPE[FLOAT][:sym] = #{$with_type_float}
+DLTYPE[DOUBLE][:sym]= #{$with_type_double}
+DLTYPE[VOIDP][:sym] = #{$with_type_voidp}
+EOF
+
+$INSTALLFILES = [
+  ["./dlconfig.h", "$(archdir)$(target_prefix)", "."],
+  ["dl.h", "$(archdir)$(target_prefix)", ""],
+]
+
+create_makefile('dl')
diff --git a/ext/dl/h2rb b/ext/dl/h2rb
new file mode 100644
index 0000000000..00fbd60c82
--- /dev/null
+++ b/ext/dl/h2rb
@@ -0,0 +1,500 @@
+#!/usr/bin/env ruby
+# -*- ruby -*-
+# $Id$
+
+require 'mkmf'
+require 'ftools'
+
+$recursive = false
+$force     = false
+$conly     = true
+$inc_path  = []
+$infilename= nil
+$insert_require = true
+
+def valid_ruby_code?(code)
+  begin
+    eval("BEGIN {return true}; #{code}")
+  rescue SyntaxError
+    return false
+  end
+  return false
+end
+
+def print_usage
+  print <<EOF
+h2rb [-r] [-I <path>] [-d] [<filename>]
+EOF
+end
+
+while( ARGV[0] )
+  case( ARGV[0] )
+  when "-r"
+    ARGV.shift
+    $recursive = true
+  when "-R"
+    ARGV.shift
+    $recursive = false
+  when "-l"
+    ARGV.shift
+    $insert_require = true
+  when "-L"
+    ARGV.shift
+    $insert_require = false
+  when "-c"
+    ARGV.shift
+    $conly = true
+  when "-C"
+    ARGV.shift
+    $conly = false
+  when "-f"
+    ARGV.shift
+    $force = true
+  when "-F"
+    ARGV.shift
+    $force = false
+  when "-I"
+    ARGV.shift
+    $inc_path << ARGV.shift
+  when "-d"
+    ARGV.shift
+    $DEBUG = true
+  when "-h","--help"
+    print_usage()
+    exit 0
+  when /-.*/
+    $stderr.print("unknown option '#{ARGV[0]}'.\n")
+    print_usage()
+    exit 0
+  else
+    $infilename = ARGV.shift
+  end
+end
+
+$inc_dir = File.join(CONFIG["prefix"], "lib", "ruby",
+		     CONFIG["MAJOR"] + "." + CONFIG["MINOR"],
+		     "dl")
+
+class H2RBError < StandardError; end
+
+
+class H2RB
+  def initialize(inc_dir = nil, inc_path = nil, insert_require = nil)
+    @inc_path = inc_path || []
+    @inc_dir  = inc_dir  || '.'
+    @indent = 0
+    @parsed_files = []
+    @insert_require = insert_require || false
+  end
+
+  def find_path(file)
+    if( ! file )
+      return nil
+    end
+    if( File.exist?(file) )
+      if( file[0] == ?/ )
+	return file
+      else
+	return file
+      end
+    end
+    @inc_path.each{|path|
+    full = File.join(path, file)
+      if( File.exist?(full) )
+	return full
+      end
+    }
+    return nil
+  end
+
+  def strip_comment(line)
+    if( @commented )
+      if( e = line.index("*/") )
+	line[0..(e+1)] = ""
+	@commented = false
+      else
+	line = ""
+      end
+    else
+      if( s = line.index("/*") )
+	if( e = line.index("*/") )
+	  line[s..(e+1)] = ""
+	else
+	  line[s..-1] = ""
+	  @commented = true
+	end
+      elsif( s = line.index("//") )
+	line[s..(-1)] = ""
+      end
+    end
+      
+    line.gsub!(/\s+$/,"")
+    return line
+  end
+  
+  def up_indent
+    @indent += 1
+  end
+  
+  def down_indent
+    @indent -= 1
+    if( @indent < 0 )
+      raise
+    end
+  end
+  
+  def indent
+    "  " * @indent
+  end
+
+  def rescue_begin
+    line = "#{indent}begin"
+    up_indent
+    return line
+  end
+
+  def rescue_nameerror
+    down_indent
+    line = [
+      "#{indent}rescue NameError => e",
+      "#{indent}  raise e if( $DEBUG )",
+      "#{indent}end"].join($/)
+    return line
+  end
+
+  def parse_enum(line)
+    if( line =~ /enum\s+(\S+\s+)?\{(.+)\}/ )
+      enum_name  = $1
+      enum_block = $2
+      if( enum_name )
+	line = "#{indent}# -- enum #{enum_name}\n"
+      else
+	line = "#{indent}# -- enum\n"
+      end
+      enums = enum_block.split(/,/).collect{|e| e.strip}
+      i = 0
+      enums.each{|elem|
+	var,val = elem.split(/=/).collect{|e| e.strip}
+	if( val )
+	  i = val.to_i
+	end
+	line += "#{indent}#{var} = #{i.to_s}\n"
+	i += 1
+      }
+      line += "#{indent}# -- end of enum"
+      return line
+    else
+      return nil
+    end
+  end
+
+  def parse_define(line)
+    case line
+    when /^#\s*define\s+(\S+)\(\)/
+      line = nil
+    when /^#\s*define\s+(\S+)\((.+)\)\s+(.+)$/
+      if( @conly )
+	line = nil
+      else
+	defname = $1
+	defargs = $2
+	defval  = $3
+	if( !valid_ruby_code?(defval) )
+	  defval = "nil # #{defval}"
+	end
+	if( defname[0,1] =~ /^[A-Z]$/ )
+	  line = "#{indent}#{defname} = proc{|#{defargs}| #{defval}}"
+	else
+	  line = [
+	    "#{indent}def #{defname}(#{defargs})",
+	    "#{indent}  #{defval}",
+	    "#{indent}end"
+	  ].join("\n")
+	end
+      end
+    when /^#\s*define\s+(\S+)\((.+)\)$/
+      if( @conly )
+	line = nil
+      else
+	defname = $1
+	defargs = $2
+	defval  = nil
+	if( !valid_ruby_code?(defval) )
+	  defval = "nil # #{defval}"
+	end
+	if( defname[0,1] =~ /^[A-Z]$/ )
+	  line = "#{indent}#{defname} = proc{|#{defargs}| #{defval}}"
+	else
+	  line = [
+	    "#{indent}def #{defname}(#{defargs})",
+	    "#{indent}  #{defval}",
+	    "#{indent}end"
+	  ].join("\n")
+	end
+      end
+    when /^#\s*define\s+(\S+)\s+(.+)$/
+      defname = $1
+      defval  = $2
+      if( !valid_ruby_code?(defval) )
+	defval = "nil # #{defval}"
+      end
+      line = [rescue_begin, "#{indent}#{defname} = #{defval}", rescue_nameerror].join($/)
+    when /^#\s*define\s+(\S+)$/
+      defname = $1
+      line = "#{indent}#{defname} = nil"
+    else
+      line = nil
+    end
+    return line
+  end
+  
+  def parse_undef(line)
+    case line
+    when /^#\s*undef\s+([A-Z]\S+)$/
+      defname = $1
+      line = "#{indent}remove_const(:#{defname})"
+    when /^#\s*undef\s+(\S+)$/
+      defname = $1
+      line = "#{indent}#{defname} = nil"
+    else
+      line = nil
+    end
+    return line
+  end
+  
+  def parse_ifdef(line)
+    case line
+    when /^#\s*ifdef\s+(\S+)$/
+      defname = $1
+      line = [
+	rescue_begin,
+	"#{indent}if( defined?(#{defname}) && ! #{defname}.nil? )"].join($/)
+    else
+      line = nil
+    end
+    return line
+  end
+  
+  def parse_ifndef(line)
+    case line
+    when /^#\s*ifndef\s+(\S+)$/
+      defname = $1
+      line = [
+	rescue_begin,
+	"#{indent}if( ! defined?(#{defname}) || #{defname}.nil? )"].join($/)
+    else
+      line = nil
+    end
+    return line
+  end
+  
+  def parse_if(line)
+    case line
+    when /^#\s*if\s+(.+)$/
+      cond = $1
+      cond.gsub!(/defined(.+)/){ "defined?(#{$1}) && ! #{$1}.nil?" }
+      if( valid_ruby_code?(cond) )
+	line = "#{indent}if( #{cond} )"
+      else
+	line = "#{indent}if( false ) # #{cond}"
+      end
+      line = [rescue_begin, line].join($/)
+    else
+      line = nil
+    end
+    return line
+  end
+  
+  def parse_elif(line)
+    case line
+    when /^#\s*elif\s+(.+)$/
+      cond = $1
+      cond.gsub!("defined","defined?")
+      line = "#{indent}elsif( #{cond} )"
+    else
+      line = nil
+    end
+    return line
+  end
+  
+  def parse_else(line)
+    case line
+    when /^#\s*else\s*/
+      line = "#{indent}else"
+    else
+      line = nil
+    end
+    return line
+  end
+  
+  def parse_endif(line)
+    case line
+    when /^#\s*endif\s*$/
+      line = ["#{indent}end", rescue_nameerror].join($/)
+    else
+      line = nil
+    end
+    return line
+  end
+  
+  def parse_include(line)
+    if( ! @insert_require )
+      return nil
+    end
+
+    file = nil
+    case line
+    when /^#\s*include "(.+)"$/
+      file = $1
+      line = "#{indent}require '#{file}'"
+    when /^#\s*include \<(.+)\>$/
+      file = $1
+      line = "#{indent}require '#{file}'"
+    else
+      line = nil
+    end
+    if( @recursive && file && (!@parsed_files.include?(file)) )
+      parse(file, @recursive, @force, @conly)
+    end
+    return line
+  end
+
+
+  def open_files(infilename)
+    if( ! infilename )
+      return [$stdin, $stdout]
+    end
+
+    old_infilename = infilename
+    infilename = find_path(infilename)
+    if( ! infilename )
+      $stderr.print("'#{old_infilename}' was not found.\n")
+      return [nil,nil]
+    end
+
+    if( infilename )
+      if( infilename[0,1] == '/' )
+	outfilename = File.join(@inc_dir, infilename[1..-1] + ".rb")
+      else
+	outfilename = infilename + ".rb"
+      end
+      File.mkpath(File.dirname(outfilename))
+    else
+      outfilename = nil
+    end
+    
+    if( infilename )
+      fin    = File.open(infilename,"r")
+    else
+      fin    = $stdin
+    end
+    if( outfilename )
+      if( File.exist?(outfilename) && (!@force) )
+	$stderr.print("'#{outfilename}' have already existed.\n")
+	return [fin, nil]
+      end
+      fout   = File.open(outfilename,"w")
+    else
+      fout   = $stdout
+    end
+
+    $stderr.print("#{infilename} -> #{outfilename}\n")
+    if( fout )
+      dir = File.dirname(outfilename)
+      if( dir[0,1] != "." && dir != "" )
+	fout.print("if( ! $LOAD_PATH.include?('#{dir}') )\n",
+		   "  $LOAD_PATH.push('#{dir}')\n",
+		   "end\n")
+      end
+    end
+    return [fin,fout]
+  end
+
+  def parse(infilename = nil, recursive = false, force = false, conly = false)
+    @commented = false
+    @recursive = recursive
+    @force     = force
+    @conly     = conly
+    @parsed_files << infilename
+
+    fin,fout = open_files(infilename)
+    if( !fin )
+      return
+    end
+
+    begin
+      line_number = 0
+      pre_line    = nil
+      fin.each_line{|line|
+	line_number += 1
+	line.chop!
+	if( $DEBUG )
+	  $stderr.print("#{line_number}:(#{@indent}):", line, "\n")
+	end
+	
+	if( pre_line )
+	  line = pre_line + line
+	  pre_line = nil
+	end
+
+	if( line[-1,1] == "\\" )
+	  pre_line = line[0..-2]
+	  next
+	end
+
+	if( eidx = line.index("enum ") )
+	  pre_line = line[eidx .. -1]
+	  if( i = line.index("{") && j = line.index("}") )
+	    line = line[0..j]
+	    pre_line = nil
+	  else
+	    next
+	  end
+	end
+
+	line = strip_comment(line)
+	case line
+	when /^enum\s/
+	  line = parse_enum(line)
+	when /^#\s*define\s/
+	  line = parse_define(line)
+	when /^#\s*undef\s/
+	  line = parse_undef(line)
+	when /^#\s*ifdef\s/
+	  line = parse_ifdef(line)
+	  up_indent
+	when /^#\s*ifndef\s/
+	  line = parse_ifndef(line)
+	  up_indent
+	when /^#\s*if\s/
+	  line = parse_if(line)
+	  up_indent
+	when /^#\s*elif\s/
+	  down_indent
+	  line = parse_elif(line)
+	  up_indent
+	when /^#\s*else/
+	  down_indent
+	  line = parse_else(line)
+	  up_indent
+	when /^#\s*endif/
+	  down_indent
+	  line = parse_endif(line)
+	when /^#\s*include\s/
+	  line = parse_include(line)
+	else
+	  line = nil
+	end
+	if( line && fout )
+	  fout.print(line, "     # #{line_number}",$/)
+	end
+      }
+    ensure
+      fin.close if fin
+      fout.close if fout
+    end
+  end
+end
+
+h2rb = H2RB.new($inc_dir, $inc_path, $insert_require)
+h2rb.parse($infilename, $recursive, $force, $conly)
diff --git a/ext/dl/handle.c b/ext/dl/handle.c
new file mode 100644
index 0000000000..d75cb11a8c
--- /dev/null
+++ b/ext/dl/handle.c
@@ -0,0 +1,207 @@
+/* -*- C -*-
+ * $Id$
+ */
+
+#include <ruby.h>
+#include "dl.h"
+
+VALUE rb_cDLHandle;
+
+void
+dlhandle_free(struct dl_handle *dlhandle)
+{
+  if( dlhandle->ptr && dlhandle->open && dlhandle->enable_close ){
+    dlclose(dlhandle->ptr);
+  };
+};
+
+VALUE
+rb_dlhandle_close(VALUE self)
+{
+  struct dl_handle *dlhandle;
+
+  Data_Get_Struct(self, struct dl_handle, dlhandle);
+  dlhandle->open = 0;
+  return INT2NUM(dlclose(dlhandle->ptr));
+};
+
+VALUE
+rb_dlhandle_s_new(int argc, VALUE argv[], VALUE self)
+{
+  void *ptr;
+  VALUE val;
+  struct dl_handle *dlhandle;
+  VALUE lib, flag;
+  char  *clib;
+  int   cflag;
+  const char *err;
+
+  switch( rb_scan_args(argc, argv, "11", &lib, &flag) ){
+  case 1:
+    clib = STR2CSTR(lib);
+    cflag = RTLD_LAZY | RTLD_GLOBAL;
+    break;
+  case 2:
+    clib = STR2CSTR(lib);
+    cflag = NUM2INT(flag);
+    break;
+  default:
+    rb_bug("rb_dlhandle_new");
+  };
+
+  ptr = dlopen(clib, cflag);
+#if defined(HAVE_DLERROR)
+  if( (err = dlerror()) ){
+    rb_raise(rb_eRuntimeError, err);
+  };
+#else
+  if( !ptr ){
+    err = dlerror();
+    rb_raise(rb_eRuntimeError, err);
+  };
+#endif
+  val = Data_Make_Struct(rb_cDLHandle, struct dl_handle, 0,
+			 dlhandle_free, dlhandle);
+  dlhandle->ptr = ptr;
+  dlhandle->open = 1;
+  dlhandle->enable_close = 0;
+
+  rb_obj_call_init(val, argc, argv);
+
+  if( rb_block_given_p() ){
+    rb_ensure(rb_yield, val, rb_dlhandle_close, val);
+  };
+
+  return val;
+};
+
+VALUE
+rb_dlhandle_init(int argc, VALUE argv[], VALUE self)
+{
+  return Qnil;
+};
+
+VALUE
+rb_dlhandle_enable_close(VALUE self)
+{
+  struct dl_handle *dlhandle;
+
+  Data_Get_Struct(self, struct dl_handle, dlhandle);
+  dlhandle->enable_close = 1;
+  return Qnil;
+};
+
+VALUE
+rb_dlhandle_disable_close(VALUE self)
+{
+  struct dl_handle *dlhandle;
+
+  Data_Get_Struct(self, struct dl_handle, dlhandle);
+  dlhandle->enable_close = 0;
+  return Qnil;
+};
+
+VALUE
+rb_dlhandle_to_i(VALUE self)
+{
+  struct dl_handle *dlhandle;
+
+  Data_Get_Struct(self, struct dl_handle, dlhandle);
+  return DLLONG2NUM(dlhandle);
+};
+
+VALUE
+rb_dlhandle_to_ptr(VALUE self)
+{
+  struct dl_handle *dlhandle;
+
+  Data_Get_Struct(self, struct dl_handle, dlhandle);
+  return rb_dlptr_new(dlhandle, sizeof(dlhandle), 0);
+};
+
+VALUE
+rb_dlhandle_sym(int argc, VALUE argv[], VALUE self)
+{
+  VALUE sym, type;
+  void (*func)();
+  VALUE val;
+  struct sym_data *data;
+  int *ctypes;
+  int i, ctypes_len;
+  struct dl_handle *dlhandle;
+  void *handle;
+  const char *name, *stype;
+  const char *err;
+
+  if( rb_scan_args(argc, argv, "11", &sym, &type) == 2 ){
+    Check_Type(type, T_STRING);
+    stype = STR2CSTR(type);
+  }
+  else{
+    stype = NULL;
+  };
+
+  if( sym == Qnil ){
+#if defined(RTLD_NEXT)
+    name = RTLD_NEXT;
+#else
+    name = NULL;
+#endif
+  }
+  else{
+    Check_Type(sym, T_STRING);
+    name = STR2CSTR(sym);
+  };
+
+
+  Data_Get_Struct(self, struct dl_handle, dlhandle);
+  handle = dlhandle->ptr;
+
+  func = dlsym(handle, name);
+#if defined(HAVE_DLERROR)
+  if( (err = dlerror()) && (!func) )
+#else
+  if( !func )
+#endif
+  {
+#if defined(__CYGWIN__) || defined(WIN32) || defined(__MINGW32__)
+    {
+      int  len = strlen(name);
+      char *name_a = (char*)dlmalloc(len+2);
+      strcpy(name_a, name);
+      name_a[len]   = 'A';
+      name_a[len+1] = '\0';
+      func = dlsym(handle, name_a);
+      dlfree(name_a);
+#if defined(HAVE_DLERROR)
+      if( (err = dlerror()) && (!func) )
+#else
+      if( !func )
+#endif
+      {
+	rb_raise(rb_eRuntimeError, "Unknown symbol \"%sA\".", name);
+      };
+    }
+#else
+    rb_raise(rb_eRuntimeError, "Unknown symbol \"%s\".", name);
+#endif
+  };
+  val = rb_dlsym_new(func, name, stype);
+
+  return val;
+};
+
+void
+Init_dlhandle()
+{
+  rb_cDLHandle = rb_define_class_under(rb_mDL, "Handle", rb_cData);
+  rb_define_singleton_method(rb_cDLHandle, "new", rb_dlhandle_s_new, -1);
+  rb_define_method(rb_cDLHandle, "initialize", rb_dlhandle_init, -1);
+  rb_define_method(rb_cDLHandle, "to_i", rb_dlhandle_to_i, 0);
+  rb_define_method(rb_cDLHandle, "to_ptr", rb_dlhandle_to_ptr, 0);
+  rb_define_method(rb_cDLHandle, "close", rb_dlhandle_close, 0);
+  rb_define_method(rb_cDLHandle, "sym",  rb_dlhandle_sym, -1);
+  rb_define_method(rb_cDLHandle, "[]",  rb_dlhandle_sym, -1);
+  rb_define_method(rb_cDLHandle, "disable_close", rb_dlhandle_disable_close, 0);
+  rb_define_method(rb_cDLHandle, "enable_close", rb_dlhandle_enable_close, 0);
+};
diff --git a/ext/dl/install.rb b/ext/dl/install.rb
new file mode 100644
index 0000000000..69b1834301
--- /dev/null
+++ b/ext/dl/install.rb
@@ -0,0 +1,49 @@
+require 'mkmf'
+require 'ftools'
+
+SO_LIBS = ["dl.so"]
+
+$ruby_version = CONFIG['MAJOR'] + "." + CONFIG['MINOR']
+$prefix = CONFIG['prefix']
+$libdir = File.join($prefix,'lib')
+$rubylibdir = File.join($libdir, 'ruby', $ruby_version)
+$arch = CONFIG['arch']
+$archdir = File.join($rubylibdir, $arch)
+
+def find(dir, match = /./)
+  Dir.chdir(dir)
+  files = []
+  Dir.new(".").each{|file|
+    if( file != "." && file != ".." )
+      case File.ftype(file)
+      when "file"
+	if( file =~ match )
+	  files.push(File.join(dir,file))
+	end
+      when "directory"
+	files += find(file, match).collect{|f| File.join(dir,f)}
+      end
+    end
+  }
+  Dir.chdir("..")
+  return files
+end
+
+def install()
+  rb_files = find(File.join(".","lib"), /.rb$/)
+
+  SO_LIBS.each{|f|
+    File.makedirs($rubylibdir, "#{$archdir}")
+    File.install(f, File.join($archdir,f), 0555, true)
+  }
+
+  rb_files.each{|f|
+    origfile = f
+    instfile = File.join($rubylibdir, origfile.sub("./lib/",""))
+    instdir  = File.dirname(instfile)
+    File.makedirs(instdir)
+    File.install(origfile, instfile, 0644, true)
+  }
+end
+
+install()
diff --git a/ext/dl/lib/dl/import.rb b/ext/dl/lib/dl/import.rb
new file mode 100644
index 0000000000..78f6a2b785
--- /dev/null
+++ b/ext/dl/lib/dl/import.rb
@@ -0,0 +1,228 @@
+# -*- ruby -*-
+
+require 'dl'
+
+module DL
+  module Importable
+    LIB_MAP = {}
+
+    module Internal
+      def dlload(*libnames)
+	if( !defined?(@LIBS) )
+	  @LIBS = []
+	end
+	libnames.each{|libname|
+	  if( !LIB_MAP[libname] )
+	    LIB_MAP[libname] = DL.dlopen(libname)
+	  end
+	  @LIBS.push(LIB_MAP[libname])
+	}
+      end
+      alias dllink :dlload
+
+      # example:
+      #   extern "int strlen(char*)"
+      #
+      def extern(proto)
+	proto = proto.gsub(/\s+/, " ").strip
+	case proto
+	when /^([\d\w\*_\s]+)\(([\d\w\*_\s\,\[\]]*)\)$/
+	  ret = $1
+	  args = $2
+	  ret = ret.split(/\s+/)
+	  args = args.split(/\s*,\s*/)
+	  func = ret.pop
+	  ret  = ret.join(" ")
+	  return import(func, ret, args)
+	else
+	  raise(RuntimeError,"can't parse the function prototype: #{proto}")
+	end
+      end
+
+      # example:
+      #   import("get_length", "int", ["void*", "int"])
+      #
+      def import(name, rettype, argtypes = nil)
+	if( !defined?(@SYM) )
+	  @SYM   = {}
+	end
+	@LIBS.each{|lib|
+	  rty,_,rdec = encode_type(rettype)
+	  ty,enc,dec = encode_types(argtypes)
+	  symty = rty + ty
+
+	  begin
+	    sym = lib[name, symty]
+	  rescue
+	    next
+	  end
+
+	  mname = name.dup
+	  if( ?A <= mname[0] && mname[0] <= ?Z )
+	    mname[0,1] = mname[0,1].downcase
+	  end
+	  @SYM[mname] = [sym,rdec,enc,dec]
+	  
+	  module_eval [
+	    "def #{mname}(*args)",
+	    "  sym,rdec,enc,dec  = @SYM['#{mname}']",
+	    "  args = enc.call(args)",
+	    if( $DEBUG )
+	      "  p \"[DL] call #{mname} with \#{args.inspect}\""
+	    else
+	      ""
+	    end,
+	    "  r,rs = sym.call(*args)",
+	    if( $DEBUG )
+	      "  p \"[DL] retval=\#{r.inspect} args=\#{rs.inspect}\""
+	    else
+	      ""
+	    end,
+	    "  @retval = rdec.call(r)",
+	    "  @args   = dec.call(rs)",
+	    "  return @retval",
+	    "end",
+	    "module_function :#{mname}",
+	  ].join("\n")
+
+	  return @SYM[mname]
+	}
+	raise(RuntimeError, "can't find #{name}.")
+      end
+
+      def _args_
+	return @args
+      end
+
+      def _retval_
+	return @retval
+      end
+      
+      def typealias(ty1, ty2, enc=nil, dec=nil)
+	check_type
+	@TYDEFS.unshift([ty1,ty2, enc,dec])
+      end
+
+      def encode_type(ty)
+	check_type
+	orig_ty = ty
+	enc = proc{|v| v}
+	dec = proc{|v| v}
+	@TYDEFS.each{|t1,t2,c1,c2|
+	  if( t1.is_a?(String) )
+	    t1 = Regexp.new("^" + t1 + "$")
+	  end
+	  if( ty =~ t1 )
+	    ty = ty.gsub(t1,t2)
+	    if( c1 )
+	      conv1 = enc
+	      enc = proc{|v| c1.call(conv1.call(v))}
+	    end
+	    if( c2 )
+	      conv2 = dec
+	      dec = proc{|v| c2.call(conv2.call(v))}
+	    end
+	  end
+	}
+	ty = ty.strip
+	if( ty.length != 1 )
+	  raise(TypeError, "unknown type: #{orig_ty}.")
+	end
+	return [ty,enc,dec]
+      end
+
+      def encode_types(tys)
+	encty = []
+	enc = proc{|v| v}
+	dec = proc{|v| v}
+	tys.each_with_index{|ty,idx|
+	  ty,c1,c2 = encode_type(ty)
+	  encty.push(ty)
+	  conv1 = enc
+	  enc = proc{|v| v = conv1.call(v); v[idx] = c1.call(v[idx]); v}
+	  conv2 = dec
+	  dec = proc{|v| v = conv2.call(v); v[idx] = c2.call(v[idx]); v}
+	}
+	return [encty.join, enc, dec]
+      end
+
+      def check_type
+	if( !defined?(@TYDEFS) )
+	  init_type
+	end
+      end
+      
+      def init_type
+	@TYDEFS = [
+	  # for Windows
+	  ["DWORD",  "unsigned long", nil, nil],
+	  ["PDWORD", "unsigned long *", nil, nil],
+	  ["WORD",   "unsigned int", nil, nil],
+	  ["PWORD",  "unsigned int *", nil, nil],
+	  ["BOOL",   "ibool", nil, nil],
+	  ["ATOM",   "int", nil, nil],
+	  ["BYTE",   "unsigned char", nil, nil],
+	  ["PBYTE",  "unsigned char *", nil, nil],
+	  ["UINT",   "unsigned int", nil, nil],
+	  ["ULONG",  "unsigned long", nil, nil],
+	  ["UCHAR",  "unsigned char", nil, nil],
+	  ["HANDLE", "unsigned long", nil, nil],
+	  ["PHANDLE","void*", nil, nil],
+	  ["PVOID",  "void*", nil, nil],
+	  ["LPCSTR", "char*", nil, nil],
+
+	  # Others
+	  ["uint",   "unsigned int", nil, nil],
+	  ["u_int",  "unsigned int", nil, nil],
+	  ["ulong",  "unsigned long", nil, nil],
+	  ["u_long", "unsigned long", nil, nil],
+
+	  # DL::Importable primitive types
+	  ["ibool",   "I",
+	    proc{|v| v ? 1 : 0},
+	    proc{|v| (v != 0) ? true : false}],
+	  ["cbool",   "C",
+	    proc{|v| v ? 1 : 0},
+	    proc{|v| (v != 0) ? true : false}],
+	  ["lbool",   "L",
+	    proc{|v| v ? 1 : 0},
+	    proc{|v| (v != 0) ? true : false}],
+	  ["unsigned char", "I",
+	    proc{|v| [v].pack("C").unpack("c")[0]},
+	    proc{|v| [v].pack("c").unpack("C")[0]}],
+	  ["unsigned int", "I",
+	    proc{|v| [v].pack("I").unpack("i")[0]},
+	    proc{|v| [v].pack("i").unpack("I")[0]}],
+	  ["unsigned long", "L",
+	    proc{|v| [v].pack("L").unpack("l")[0]},
+	    proc{|v| [v].pack("l").unpack("L")[0]}],
+	  ["unsigned char ref", "i",
+	    proc{|v| [v].pack("C").unpack("c")[0]},
+	    proc{|v| [v].pack("c").unpack("C")[0]}],
+	  ["unsigned int ref", "i",
+	    proc{|v| [v].pack("I").unpack("i")[0]},
+	    proc{|v| [v].pack("i").unpack("I")[0]}],
+	  ["unsigned long ref", "l",
+	    proc{|v| [v].pack("L").unpack("l")[0]},
+	    proc{|v| [v].pack("l").unpack("L")[0]}],
+	  ["char ref",  "c", nil, nil],
+	  ["short ref", "h", nil, nil],
+	  ["int ref",   "i", nil, nil],
+	  ["long ref",  "l", nil, nil],
+	  ["float ref", "f", nil, nil],
+	  ["double ref","d", nil, nil],
+	  ["char",   "C", nil, nil],
+	  ["short",  "H", nil, nil],
+	  ["int",    "I", nil, nil],
+	  ["long",   "L", nil, nil],
+	  ["float",  "F", nil, nil],
+	  ["double", "D", nil, nil],
+	  [/.+\*/,   "P", nil, nil],
+	  [/.+\[\]/, "a", nil, nil],
+	  ["void",   "0", nil, nil],
+	]
+      end
+    end # end of Internal
+    include Internal
+  end # end of Importable
+end
diff --git a/ext/dl/lib/dl/win32.rb b/ext/dl/lib/dl/win32.rb
new file mode 100644
index 0000000000..b507be5fde
--- /dev/null
+++ b/ext/dl/lib/dl/win32.rb
@@ -0,0 +1,26 @@
+# -*- ruby -*-
+
+require 'dl'
+
+class Win32API
+  LIBRARY = {}
+
+  attr_reader :val, :args
+
+  def initialize(lib, func, args, ret)
+    LIBRARY[lib] ||= DL.dlopen(lib)
+    ty = (ret + args).tr('V','0')
+    @sym = LIBRARY[lib].sym(func, ty)
+    @__dll__ = LIBRARY[lib].to_i
+    @__dllname__ = lib
+    @__proc__ = @sym.to_i
+    @val = nil
+    @args = []
+  end
+
+  def call(*args)
+    @val,@args = @sym.call(*args)
+    return @val
+  end
+  alias Call call
+end
diff --git a/ext/dl/mkcall.rb b/ext/dl/mkcall.rb
new file mode 100644
index 0000000000..dad101744b
--- /dev/null
+++ b/ext/dl/mkcall.rb
@@ -0,0 +1,68 @@
+# -*- ruby -*-
+
+require 'mkmf'
+$:.unshift File.dirname(__FILE__)
+require 'type'
+require 'dlconfig'
+
+$int_eq_long = try_run(<<EOF)
+int main() {
+  return sizeof(int) == sizeof(long) ? 0 : 1;
+}
+EOF
+
+def output_arg(x,i)
+  "args[#{i}].#{DLTYPE[x][:stmem]}"
+end
+
+def output_args(types)
+  t = []
+  types[1..-1].each_with_index{|x,i| t.push(output_arg(x,i))}
+  t.join(",")
+end
+
+def output_callfunc(types)
+  t = types[0]
+  stmem = DLTYPE[t][:stmem]
+  ctypes = types2ctypes(types)
+  if( t == VOID )
+    callstm = "(*f)(#{output_args(types)})"
+  else
+    callstm = "ret.#{stmem} = (*f)(#{output_args(types)})"
+  end
+  [ "{",
+    "#{ctypes[0]} (*f)(#{ctypes[1..-1].join(',')}) = func;",
+    "#{callstm};",
+    "}"].join(" ")
+end
+
+def output_case(types)
+  num = types2num(types)
+  callfunc_stm = output_callfunc(types)
+<<EOF
+  case #{num}:
+#ifdef DEBUG
+    printf("#{callfunc_stm}\\n");
+#endif
+    #{callfunc_stm};
+    break;
+EOF
+end
+
+def rec_output(types = [VOID])
+  print output_case(types)
+  if( types.length <= MAX_ARG )
+    DLTYPE.keys.sort.each{|t|
+      if( t != VOID && DLTYPE[t][:sym] )
+	rec_output(types + [t])
+      end
+    }
+  end
+end
+
+DLTYPE.keys.sort.each{|t|
+  if( DLTYPE[t][:sym] )
+    $stderr.printf("  #{DLTYPE[t][:ctype]}\n")
+    rec_output([t])
+  end
+}
diff --git a/ext/dl/mkcallback.rb b/ext/dl/mkcallback.rb
new file mode 100644
index 0000000000..32c7b451d7
--- /dev/null
+++ b/ext/dl/mkcallback.rb
@@ -0,0 +1,83 @@
+# -*- ruby -*-
+
+require 'mkmf'
+$:.unshift File.dirname(__FILE__)
+require 'type'
+require 'dlconfig'
+
+$int_eq_long = try_run(<<EOF)
+int main() {
+  return sizeof(int) == sizeof(long) ? 0 : 1;
+}
+EOF
+
+def func_arg(x,i)
+  ctype = DLTYPE[x][:ctype]
+  "#{ctype} arg#{i}"
+end
+
+def func_args(types)
+  t = []
+  types[1..-1].each_with_index{|x,i| t.push(func_arg(x,i))}
+  t.join(", ")
+end
+
+def funcall_args(types)
+  num = types.length - 1
+  if( num > 0 )
+    t = []
+    types[1..-1].each_with_index{|x,i| t.push(DLTYPE[x][:c2rb].call("arg#{i}"))}
+    return num.to_s + ", " + t.join(", ")
+  else
+    return num.to_s
+  end
+end
+
+def output_func(types, n = 0)
+  func_name = "rb_dl_func#{types2num(types)}_#{n}"
+  code =
+    "#{func_name}(#{func_args(types)}) /* #{types2ctypes(types).inspect} */\n" +
+    "{\n" +
+    "  VALUE val, obj;\n" +
+    "#ifdef DEBUG\n" +
+    "  printf(\"#{func_name}()\\n\");\n" +
+    "#endif\n" +
+    "  obj = rb_hash_aref(DLFuncTable, INT2NUM(#{types2num(types)}));\n" +
+    "  obj = rb_hash_aref(obj,INT2NUM(#{n}));\n" +
+    "  val = rb_funcall(obj, id_call,\n" +
+    "                   #{funcall_args(types)});\n"
+
+  rtype = DLTYPE[types[0]][:ctype]
+  rcode = DLTYPE[types[0]][:rb2c]
+  if( rcode )
+    code += "  return #{rcode.call('val')};\n"
+  end
+
+  code =
+    rtype + "\n" +
+    code +
+    "}\n\n"
+  if( n < MAX_CBENT - 1)
+    return code + output_func(types, n+1)
+  else
+    return code
+  end
+end
+
+
+def rec_output(types = [VOID])
+  print output_func(types)
+  if( types.length <= MAX_CBARG )
+    DLTYPE.keys.sort.each{|t|
+      if( t != VOID && DLTYPE[t][:cb] )
+	rec_output(types + [t])
+      end
+    }
+  end
+end
+
+DLTYPE.keys.sort.each{|t|
+  if( DLTYPE[t][:cb] )
+    rec_output([t])
+  end
+}
diff --git a/ext/dl/mkcbtable.rb b/ext/dl/mkcbtable.rb
new file mode 100644
index 0000000000..f25f012e4c
--- /dev/null
+++ b/ext/dl/mkcbtable.rb
@@ -0,0 +1,42 @@
+# -*- ruby -*-
+
+require 'mkmf'
+$:.unshift File.dirname(__FILE__)
+require 'type'
+require 'dlconfig'
+
+$int_eq_long = try_run(<<EOF)
+int main() {
+  return sizeof(int) == sizeof(long) ? 0 : 1;
+}
+EOF
+
+def output_func(types, n = 0)
+  code =
+    "/* #{types2ctypes(types).inspect} */\n" +
+    "rb_dl_func_table[#{types2num(types)}][#{n}] " +
+    "= rb_dl_func#{types2num(types)}_#{n};\n"
+  if( n < MAX_CBENT - 1)
+    return code + output_func(types, n+1)
+  else
+    return code
+  end
+end
+
+
+def rec_output(types = [VOID])
+  print output_func(types)
+  if( types.length <= MAX_CBARG )
+    DLTYPE.keys.sort.each{|t|
+      if( t != VOID && DLTYPE[t][:cb] )
+	rec_output(types + [t])
+      end
+    }
+  end
+end
+
+DLTYPE.keys.sort.each{|t|
+  if( DLTYPE[t][:cb] )
+    rec_output([t])
+  end
+}
diff --git a/ext/dl/ptr.c b/ext/dl/ptr.c
new file mode 100644
index 0000000000..6ac214bc46
--- /dev/null
+++ b/ext/dl/ptr.c
@@ -0,0 +1,1075 @@
+/* -*- C -*-
+ * $Id$
+ */
+
+#include <ruby.h>
+#include <version.h> /* for ruby version code */
+#include "dl.h"
+
+VALUE rb_cDLPtrData;
+VALUE rb_mDLMemorySpace;
+static VALUE DLMemoryTable;
+
+#ifndef T_SYMBOL
+# define T_SYMBOL T_FIXNUM
+#endif
+
+#if RUBY_VERSION_CODE < 171
+static VALUE
+rb_hash_delete(VALUE hash, VALUE key)
+{
+  return rb_funcall(hash, rb_intern("delete"), 1, key);
+}
+#endif
+
+static void
+rb_dlmem_delete(void *ptr)
+{
+  rb_hash_delete(DLMemoryTable, DLLONG2NUM(ptr));
+};
+
+static void
+rb_dlmem_aset(void *ptr, VALUE obj)
+{
+  if( obj == Qnil ){
+    rb_dlmem_delete(ptr);
+  }
+  else{
+    rb_hash_aset(DLMemoryTable, DLLONG2NUM(ptr), DLLONG2NUM(obj));
+  };
+};
+
+static VALUE
+rb_dlmem_aref(void *ptr)
+{
+  VALUE val;
+
+  val = rb_hash_aref(DLMemoryTable, DLLONG2NUM(ptr));
+  return val == Qnil ? Qnil : (VALUE)DLNUM2LONG(val);
+};
+
+void
+dlptr_free(struct ptr_data *data)
+{
+  if( data->ptr ){
+    DEBUG_CODE({
+      printf("dlptr_free(): removing the pointer `0x%x' from the MemorySpace\n",
+	     data->ptr);
+    });
+    rb_dlmem_delete(data->ptr);
+    if( data->free ){
+      DEBUG_CODE({
+	printf("dlptr_free(): 0x%x(data->ptr:0x%x)\n",data->free,data->ptr);
+      });
+      (*(data->free))(data->ptr);
+    };
+  };
+  if( data->stype ) dlfree(data->stype);
+  if( data->ssize ) dlfree(data->ssize);
+  if( data->ids  ) dlfree(data->ids);
+};
+
+void
+dlptr_init(VALUE val)
+{
+  struct ptr_data *data;
+
+  Data_Get_Struct(val, struct ptr_data, data);
+  DEBUG_CODE({
+    printf("dlptr_init(): add the pointer `0x%x' to the MemorySpace\n",
+	   data->ptr);
+  });
+  rb_dlmem_aset(data->ptr, val);
+};
+
+VALUE
+rb_dlptr_new(void *ptr, long size, freefunc_t func)
+{
+  struct ptr_data *data;
+  VALUE val;
+
+  if( ptr ){
+    val = rb_dlmem_aref(ptr);
+    if( val == Qnil ){
+      val = Data_Make_Struct(rb_cDLPtrData, struct ptr_data,
+			     0, dlptr_free, data);
+      data->ptr = ptr;
+      data->free = func;
+      data->ctype = DLPTR_CTYPE_UNKNOWN;
+      data->stype = NULL;
+      data->ssize = NULL;
+      data->slen = 0;
+      data->size = size;
+      data->ids = NULL;
+      data->ids_num = 0;
+      dlptr_init(val);
+    }
+    else{
+      if( func ){
+	Data_Get_Struct(val, struct ptr_data, data);
+	data->free = func;
+      };
+    };
+  }
+  else{
+    val = Qnil;
+  };
+
+  return val;
+};
+
+VALUE
+rb_dlptr_alloc(long size, freefunc_t func)
+{
+  return rb_dlptr_new(dlmalloc((size_t)size), size, func);
+};
+
+void *
+rb_dlptr2cptr(VALUE val)
+{
+  struct ptr_data *data;
+  void *ptr;
+
+  if( rb_obj_is_kind_of(val, rb_cDLPtrData) ){
+    Data_Get_Struct(val, struct ptr_data, data);
+    ptr = data->ptr;
+  }
+  else if( val == Qnil ){
+    ptr = NULL;
+  }
+  else{
+    rb_raise(rb_eTypeError, "DL::PtrData was expected");
+  };
+    
+  return ptr;
+};
+
+static VALUE
+rb_dlptr_s_new(int argc, VALUE argv[], VALUE klass)
+{
+  VALUE ptr, sym, obj, size;
+  void *p = NULL;
+  void  (*f)() = NULL;
+  long s = 0;
+
+  switch( rb_scan_args(argc, argv, "12", &ptr, &size, &sym) ){
+  case 1:
+    p = (void*)(DLNUM2LONG(rb_Integer(ptr)));
+    break;
+  case 2:
+    p = (void*)(DLNUM2LONG(rb_Integer(ptr)));
+    s = DLNUM2LONG(size);
+    break;
+  case 3:
+    p = (void*)(DLNUM2LONG(rb_Integer(ptr)));
+    s = DLNUM2LONG(size);
+    f = rb_dlsym2csym(sym);
+    break;
+  default:
+    rb_bug("rb_dlptr_s_new");
+  };
+
+  obj = rb_dlptr_new(p,s,f);
+
+  rb_obj_call_init(obj, argc, argv);
+
+  return obj;
+};
+
+static VALUE
+rb_dlptr_s_alloc(int argc, VALUE argv[], VALUE klass)
+{
+  VALUE size, sym, obj;
+  int   s;
+  void  (*f)() = NULL;
+
+  switch( rb_scan_args(argc, argv, "11", &size, &sym) ){
+  case 1:
+    s = NUM2INT(size);
+    break;
+  case 2:
+    s = NUM2INT(size);
+    f = rb_dlsym2csym(sym);
+    break;
+  default:
+    rb_bug("rb_dlptr_s_new");
+  };
+
+  obj = rb_dlptr_alloc(s,f);
+
+  rb_obj_call_init(obj, argc, argv);
+
+  return obj;
+};
+
+static VALUE
+rb_dlptr_init(int argc, VALUE argv[], VALUE self)
+{
+  return Qnil;
+};
+
+static VALUE
+rb_dlptr_cast(int argc, VALUE argv[], VALUE self)
+{
+  VALUE klass, rest, val, *pass_argv;
+  int pass_argc, i;
+  struct ptr_data *data;
+
+  Data_Get_Struct(self, struct ptr_data, data);
+  rb_scan_args(argc, argv, "1*", &klass, &rest);
+
+  /* prepare the arguments of `new' method */
+  pass_argc = argc + 1;
+  pass_argv = ALLOCA_N(VALUE, pass_argc);
+  pass_argv[0] = DLLONG2NUM(data->ptr);
+  pass_argv[1] = rb_dlsym_new(data->free, NULL, NULL);
+  for( i=2; i < pass_argc; i++ ){
+    pass_argv[i] = rb_ary_entry(rest,i-2);
+  };
+
+  /* remove the data */
+  ((struct ptr_data *)(RDATA(self)->data))->ptr = 0;
+  (RDATA(self)->dfree)(RDATA(self)->data);
+  
+  /* call the `new' method of klass with prepared arguments */
+  val = rb_funcall2(klass, rb_intern("new"), pass_argc, pass_argv);
+
+  RDATA(self)->basic.klass = RDATA(val)->basic.klass;
+  RDATA(self)->basic.flags = RDATA(val)->basic.flags;
+  RDATA(self)->dmark = RDATA(val)->dmark;
+  RDATA(self)->dfree = RDATA(val)->dfree;
+  RDATA(self)->data = RDATA(val)->data;
+
+  RDATA(val)->dmark = 0;
+  RDATA(val)->dfree = 0;
+
+  return Qnil;
+};
+
+VALUE
+rb_dlptr_to_i(VALUE self)
+{
+  struct ptr_data *data;
+
+  Data_Get_Struct(self, struct ptr_data, data);
+  return DLLONG2NUM(data->ptr);
+};
+
+VALUE
+rb_dlptr_ptr(VALUE self)
+{
+  struct ptr_data *data;
+
+  Data_Get_Struct(self, struct ptr_data, data);
+  return rb_dlptr_new(*((void**)(data->ptr)),0,0);
+};
+
+VALUE
+rb_dlptr_ref(VALUE self)
+{
+  struct ptr_data *data;
+
+  Data_Get_Struct(self, struct ptr_data, data);
+  return rb_dlptr_new(&(data->ptr),0,0);
+};
+
+VALUE
+rb_dlptr_null_p(VALUE self)
+{
+  struct ptr_data *data;
+
+  Data_Get_Struct(self, struct ptr_data, data);
+  return data->ptr ? Qfalse : Qtrue;
+};
+
+VALUE
+rb_dlptr_free_set(VALUE self, VALUE val)
+{
+  struct ptr_data *data;
+  int i;
+
+  Data_Get_Struct(self, struct ptr_data, data);
+
+  data->free = DLFREEFUNC(rb_dlsym2csym(val));
+
+  return Qnil;
+};
+
+VALUE
+rb_dlptr_free_get(VALUE self)
+{
+  struct ptr_data *pdata;
+
+  Data_Get_Struct(self, struct ptr_data, pdata);
+
+  return rb_dlsym_new(pdata->free,"(free)","0P");
+};
+
+VALUE
+rb_dlptr_to_array(int argc, VALUE argv[], VALUE self)
+{
+  struct ptr_data *data;
+  int n;
+  int i;
+  int t;
+  VALUE ary;
+  VALUE type, size;
+
+  Data_Get_Struct(self, struct ptr_data, data);
+
+  switch( rb_scan_args(argc, argv, "11", &type, &size) ){
+  case 2:
+    t = STR2CSTR(type)[0];
+    n = NUM2INT(size);
+    break;
+  case 1:
+    t = STR2CSTR(type)[0];
+    switch( t ){
+    case 'C':
+      n = data->size;
+      break;
+    case 'H':
+      n = data->size / sizeof(short);
+      break;
+    case 'I':
+      n = data->size / sizeof(int);
+      break;
+    case 'L':
+      n = data->size / sizeof(long);
+      break;
+    case 'F':
+      n = data->size / sizeof(float);
+      break;
+    case 'D':
+      n = data->size / sizeof(double);
+      break;
+    case  'S': case 'P':
+      n = data->size / sizeof(void*);
+      break;
+    default:
+      if( t == 'p' || t == 's' ){
+	int i;
+	for( i=0; ((void**)(data->ptr))[i]; i++ ){};
+	n = i;
+      }
+      else{
+	n = 0;
+      };
+    };
+    break;
+  default:
+    rb_bug("rb_dlptr_to_array");
+  };
+
+  ary = rb_ary_new();
+
+  for( i=0; i < n; i++ ){
+    switch( t ){
+    case 'C':
+      rb_ary_push(ary, INT2NUM(((char*)(data->ptr))[i]));
+      break;
+    case 'H':
+      rb_ary_push(ary, INT2NUM(((short*)(data->ptr))[i]));
+      break;
+    case 'I':
+      rb_ary_push(ary, INT2NUM(((int*)(data->ptr))[i]));
+      break;
+    case 'L':
+      rb_ary_push(ary, DLLONG2NUM(((long*)(data->ptr))[i]));
+      break;
+    case 'D':
+      rb_ary_push(ary, rb_float_new(((double*)(data->ptr))[i]));
+    case 'F':
+      rb_ary_push(ary, rb_float_new(((float*)(data->ptr))[i]));
+      break;
+    case 'S':
+      {
+	char *str = ((char**)(data->ptr))[i];
+	if( str ){
+	  rb_ary_push(ary, rb_tainted_str_new2(str));
+	}
+	else{
+	  rb_ary_push(ary, Qnil);
+	};
+      };
+      break;
+    case 's':
+      {
+	char *str = ((char**)(data->ptr))[i];
+	if( str ){
+	  rb_ary_push(ary, rb_tainted_str_new2(str));
+	  xfree(str);
+	}
+	else{
+	  rb_ary_push(ary, Qnil);
+	};
+      };
+      break;
+    case 'P':
+      rb_ary_push(ary, rb_dlptr_new(((void**)(data->ptr))[i],0,0));
+      break;
+    case 'p':
+      rb_ary_push(ary,
+		  rb_dlptr_new(((void**)(data->ptr))[i],0,dlfree));
+      break;
+    };
+  };
+
+  return ary;
+};
+
+
+VALUE
+rb_dlptr_to_s(int argc, VALUE argv[], VALUE self)
+{
+  struct ptr_data *data;
+  VALUE arg1, val;
+  int len;
+
+  Data_Get_Struct(self, struct ptr_data, data);
+  switch( rb_scan_args(argc, argv, "01", &arg1) ){
+  case 0:
+    val = rb_tainted_str_new2((char*)(data->ptr));
+    break;
+  case 1:
+    len = NUM2INT(arg1);
+    val = rb_tainted_str_new((char*)(data->ptr), len);
+    break;
+  default:
+    rb_bug("rb_dlptr_to_s");
+  };
+
+  return val;
+};
+
+VALUE
+rb_dlptr_to_str(int argc, VALUE argv[], VALUE self)
+{
+  struct ptr_data *data;
+  VALUE arg1, val;
+  int len;
+
+  Data_Get_Struct(self, struct ptr_data, data);
+  switch( rb_scan_args(argc, argv, "01", &arg1) ){
+  case 0:
+    val = rb_tainted_str_new((char*)(data->ptr),data->size);
+    break;
+  case 1:
+    len = NUM2INT(arg1);
+    val = rb_tainted_str_new((char*)(data->ptr), len);
+    break;
+  default:
+    rb_bug("rb_dlptr_to_str");
+  };
+
+  return val;
+};
+
+VALUE
+rb_dlptr_inspect(VALUE self)
+{
+  struct ptr_data *data;
+  char str[1024];
+  VALUE name;
+
+  Data_Get_Struct(self, struct ptr_data, data);
+  snprintf(str, 1023, "#<%s:0x%x ptr=0x%x size=%ld free=0x%x>",
+	   rb_class2name(CLASS_OF(self)), data, data->ptr, data->size, data->free);
+  return rb_str_new2(str);
+};
+
+VALUE
+rb_dlptr_eql(VALUE self, VALUE other)
+{
+  void *ptr1, *ptr2;
+  ptr1 = rb_dlptr2cptr(self);
+  ptr2 = rb_dlptr2cptr(other);
+
+  return ptr1 == ptr2 ? Qtrue : Qfalse;
+};
+
+VALUE
+rb_dlptr_cmp(VALUE self, VALUE other)
+{
+  void *ptr1, *ptr2;
+  ptr1 = rb_dlptr2cptr(self);
+  ptr2 = rb_dlptr2cptr(other);
+  return DLLONG2NUM((long)ptr1 - (long)ptr2);
+};
+
+VALUE
+rb_dlptr_plus(VALUE self, VALUE other)
+{
+  void *ptr;
+  long num, size;
+
+  ptr = rb_dlptr2cptr(self);
+  size = RDLPTR(self)->size;
+  num = DLNUM2LONG(other);
+  return rb_dlptr_new((void*)(ptr + num), size - num, 0);
+};
+
+VALUE
+rb_dlptr_minus(VALUE self, VALUE other)
+{
+  void *ptr;
+  long num, size;
+
+  ptr = rb_dlptr2cptr(self);
+  size = RDLPTR(self)->size;
+  num = DLNUM2LONG(other);
+  return rb_dlptr_new((void*)(ptr - num), size + num, 0);
+};
+
+VALUE
+rb_dlptr_define_data_type(int argc, VALUE argv[], VALUE self)
+{
+  VALUE data_type, type, rest, vid;
+  struct ptr_data *data;
+  int i, t, len, num;
+  char *ctype;
+  long size;
+
+  rb_scan_args(argc, argv, "11*", &data_type, &type, &rest);
+  Data_Get_Struct(self, struct ptr_data, data);
+
+  if( argc == 1 || (argc == 2 && type == Qnil) ){
+    if( NUM2INT(data_type) == DLPTR_CTYPE_UNKNOWN ){
+      data->ctype = DLPTR_CTYPE_UNKNOWN;
+      data->slen = 0;
+      data->ids_num  = 0;
+      if( data->stype ){
+	dlfree(data->stype);
+	data->stype = NULL;
+      };
+      if( data->ids ){
+	dlfree(data->ids);
+	data->ids = NULL;
+      };
+      return Qnil;
+    }
+    else{
+      raise(rb_eArgError, "wrong arguments");
+    };
+  };
+
+  Check_Type(data_type, T_FIXNUM);
+  Check_Type(type, T_STRING);
+  Check_Type(rest, T_ARRAY);
+  t = FIX2INT(data_type);
+  num = RARRAY(rest)->len;
+  for( i=0; i<num; i++ ){
+    vid = rb_ary_entry(rest,i);
+    if( !(TYPE(vid)==T_STRING || TYPE(vid)==T_SYMBOL) ){
+      rb_raise(rb_eTypeError, "#%d must be a string or symbol", i + 2);
+    };
+  };
+
+  data->ctype = t;
+  data->slen = num;
+  data->ids_num  = num;
+  if( data->stype ) dlfree(data->stype);
+  data->stype = (char*)dlmalloc(sizeof(char) * num);
+  if( data->ssize ) dlfree(data->ssize);
+  data->ssize = (int*)dlmalloc(sizeof(int) * num);
+  if( data->ids ) dlfree(data->ids);
+  data->ids  = (ID*)dlmalloc(sizeof(ID) * data->ids_num);
+
+  ctype = STR2CSTR(type);
+  for( i=0; i<num; i++ ){
+    vid = rb_ary_entry(rest,i);
+    data->ids[i] = rb_to_id(vid);
+    data->stype[i] = *ctype;
+    ctype ++;
+    if( isdigit(*ctype) ){
+      char *p, *d;
+      for( p=ctype; isdigit(*p); p++ ) ;
+      d = ALLOCA_N(char, p - ctype + 1);
+      strncpy(d, ctype, p - ctype);
+      d[p - ctype] = '\0';
+      data->ssize[i] = atoi(d);
+      ctype = p;
+    }
+    else{
+      data->ssize[i] = 1;
+    };
+  };
+
+  if( *ctype ){
+    rb_raise(rb_eArgError, "too few/many arguments");
+  };
+
+  if( !data->size )
+    data->size = dlsizeof(STR2CSTR(type));
+
+  return Qnil;
+};
+
+VALUE
+rb_dlptr_define_struct(int argc, VALUE argv[], VALUE self)
+{
+  VALUE *pass_argv;
+  int pass_argc, i;
+
+  pass_argc = argc + 1;
+  pass_argv = ALLOCA_N(VALUE, pass_argc);
+  pass_argv[0] = INT2FIX(DLPTR_CTYPE_STRUCT);
+  for( i=1; i<pass_argc; i++ ){
+    pass_argv[i] = argv[i-1];
+  };
+  return rb_dlptr_define_data_type(pass_argc, pass_argv, self);
+};
+
+VALUE
+rb_dlptr_define_union(int argc, VALUE argv[], VALUE self)
+{
+  VALUE *pass_argv;
+  int pass_argc, i;
+
+  pass_argc = argc + 1;
+  pass_argv = ALLOCA_N(VALUE, pass_argc);
+  pass_argv[0] = INT2FIX(DLPTR_CTYPE_UNION);
+  for( i=1; i<pass_argc; i++ ){
+    pass_argv[i] = argv[i-1];
+  };
+  return rb_dlptr_define_data_type(pass_argc, pass_argv, self);
+};
+
+VALUE
+rb_dlptr_get_data_type(VALUE self)
+{
+  struct ptr_data *data;
+
+  Data_Get_Struct(self, struct ptr_data, data);
+  if( data->stype )
+    return rb_assoc_new(INT2FIX(data->ctype),
+			rb_tainted_str_new(data->stype, data->slen));
+  else
+    return rb_assoc_new(INT2FIX(data->ctype), Qnil);
+};
+
+static VALUE
+cary2ary(void *ptr, char t, int len)
+{
+  VALUE ary;
+  VALUE elem;
+  int i;
+
+  if( len < 1 )
+    return Qnil;
+
+  if( len == 1 ){
+    switch( t ){
+    case 'I': case 'i':
+      elem = INT2NUM(*((int*)ptr));
+      ptr += sizeof(int);
+      break;
+    case 'L': case 'l':
+      elem = DLLONG2NUM(*((long*)ptr));
+      ptr += sizeof(long);
+      break;
+    case 'P': case 'p':
+      elem = rb_dlptr_new(*((void**)ptr),0, 0);
+      ptr += sizeof(void*);
+      break;
+    case 'F': case 'f':
+      elem = rb_float_new(*((float*)ptr));
+      ptr += sizeof(float);
+      break;
+    case 'D': case 'd':
+      elem = rb_float_new(*((float*)ptr));
+      ptr += sizeof(double);
+      break;
+    case 'C': case 'c':
+      elem = INT2NUM(*((char*)ptr));
+      ptr += sizeof(char);
+      break;
+    case 'H': case 'h':
+      elem = INT2NUM(*((short*)ptr));
+      ptr += sizeof(short);
+    default:
+      raise(rb_eDLTypeError, "unsupported type '%c'", t);
+    };
+    return elem;
+  };
+
+  ary = rb_ary_new();
+  for( i=0; i < len; i++ ){
+    switch( t ){
+    case 'I': case 'i':
+      elem = INT2NUM(*((int*)ptr));
+      ptr += sizeof(int);
+      break;
+    case 'L': case 'l':
+      elem = DLLONG2NUM(*((long*)ptr));
+      ptr += sizeof(long);
+      break;
+    case 'P': case 'p':
+      elem = rb_dlptr_new(*((void**)ptr), 0, 0);
+      ptr += sizeof(void*);
+      break;
+    case 'F': case 'f':
+      elem = rb_float_new(*((float*)ptr));
+      ptr += sizeof(float);
+      break;
+    case 'D': case 'd':
+      elem = rb_float_new(*((float*)ptr));
+      ptr += sizeof(double);
+      break;
+    case 'C': case 'c':
+      elem = INT2NUM(*((char*)ptr));
+      ptr += sizeof(char);
+      break;
+    case 'H': case 'h':
+      elem = INT2NUM(*((short*)ptr));
+      ptr += sizeof(short);
+    default:
+      raise(rb_eDLTypeError, "unsupported type '%c'", t);
+    };
+    rb_ary_push(ary, elem);
+  };
+
+  return ary;
+};
+
+VALUE
+rb_dlptr_aref(int argc, VALUE argv[], VALUE self)
+{
+  VALUE val, key = Qnil, num = Qnil;
+  ID id;
+  int idx;
+  struct ptr_data *data;
+  int i;
+  int offset;
+
+  if( rb_scan_args(argc, argv, "11", &key, &num) == 1 ){
+    num = INT2NUM(0);
+  };
+
+  if( TYPE(key) == T_FIXNUM || TYPE(key) == T_BIGNUM ){
+    VALUE pass[] = {num};
+    return rb_dlptr_to_str(1, pass, rb_dlptr_plus(self, key));
+  };
+
+  if( ! (TYPE(key) == T_STRING || TYPE(key) == T_SYMBOL ) ){
+    rb_raise(rb_eTypeError, "the key must be a string or symbol");
+  };
+
+  id = rb_to_id(key);
+  Data_Get_Struct(self, struct ptr_data, data);
+  switch( data->ctype ){
+  case DLPTR_CTYPE_STRUCT:
+    offset = 0;
+    for( i=0; i < data->ids_num; i++ ){
+      if( data->ids[i] == id ){
+	switch( data->stype[i] ){
+	case 'I':
+	  DLALIGN(data->ptr,offset,INT_ALIGN);
+	  break;
+	case 'L':
+	  DLALIGN(data->ptr,offset,LONG_ALIGN);
+	  break;
+	case 'P':
+	  DLALIGN(data->ptr,offset,VOIDP_ALIGN);
+	case 'F':
+	  DLALIGN(data->ptr,offset,FLOAT_ALIGN);
+	  break;
+	case 'D':
+	  DLALIGN(data->ptr,offset,DOUBLE_ALIGN);
+	  break;
+	case 'C':
+	  break;
+	case 'H':
+	  DLALIGN(data->ptr,offset,SHORT_ALIGN);
+	  break;
+	default:
+	  raise(rb_eDLTypeError, "unsupported type '%c'", data->stype[i]);
+	};
+	return cary2ary(data->ptr + offset, data->stype[i], data->ssize[i]);
+      };
+      switch( data->stype[i] ){
+      case 'I':
+      case 'i':
+	offset += sizeof(int) * data->ssize[i];
+	break;
+      case 'L':
+      case 'l':
+	offset += sizeof(long) * data->ssize[i];
+	break;
+      case 'P':
+      case 'p':
+	offset += sizeof(void*) * data->ssize[i];
+	break;
+      case 'F':
+      case 'f':
+	offset += sizeof(float) * data->ssize[i];
+	break;
+      case 'D':
+      case 'd':
+	offset += sizeof(double) * data->ssize[i];
+	break;
+      case 'C':
+      case 'c':
+	offset += sizeof(char) * data->ssize[i];
+	break;
+      case 'H':
+      case 'h':
+	offset += sizeof(short) * data->ssize[i];
+	break;
+      default:
+	raise(rb_eDLTypeError, "unsupported type '%c'", data->stype[i]);
+      };
+    };
+    break;
+  case DLPTR_CTYPE_UNION:
+    for( i=0; i < data->ids_num; i++ ){
+      if( data->ids[i] == id ){
+	return cary2ary(data->ptr + offset, data->stype[i], data->ssize[i]);
+      };
+    };
+    break;
+  }; /* end of switch */
+
+  rb_raise(rb_eNameError, "undefined key `%s' for %s",
+	   rb_id2name(id), rb_class2name(CLASS_OF(self)));
+
+  return Qnil;
+};
+
+static void *
+ary2cary(char t, VALUE val, long *size)
+{
+  void *ptr;
+
+  if( TYPE(val) == T_ARRAY ){
+    ptr = rb_ary2cary(t, val, size);
+  }
+  else{
+    ptr = rb_ary2cary(t, rb_ary_new3(1, val), size);
+  };
+  return ptr;
+};
+
+VALUE
+rb_dlptr_aset(int argc, VALUE argv[], VALUE self)
+{
+  VALUE key = Qnil, num = Qnil, val = Qnil;
+  ID id;
+  struct ptr_data *data;
+  int i;
+  int offset;
+  long memsize;
+  void *memimg;
+
+  switch( rb_scan_args(argc, argv, "21", &key, &num, &val) ){
+  case 2:
+    val = num;
+    num = Qnil;
+    break;
+  };
+
+  if( TYPE(key) == T_FIXNUM || TYPE(key) == T_BIGNUM ){
+    void *dst, *src;
+    int len;
+    
+    Check_Type(val, T_STRING);
+    Data_Get_Struct(self, struct ptr_data, data);
+    dst = (void*)((long)(data->ptr) + DLNUM2LONG(key));
+    src = STR2CSTR(val);
+    if( num == Qnil ){
+      len = RSTRING(val)->len;
+    }
+    else{
+      len = NUM2INT(num);
+    };
+    memcpy(dst, src, len);
+    return val;
+  };
+
+  if( ! (TYPE(key) == T_STRING || TYPE(key) == T_SYMBOL ) ){
+    rb_raise(rb_eTypeError, "the key must be a string or symbol");
+  };
+
+  id = rb_to_id(key);
+  Data_Get_Struct(self, struct ptr_data, data);
+  switch( data->ctype ){
+  case DLPTR_CTYPE_STRUCT:
+    offset = 0;
+    for( i=0; i < data->ids_num; i++ ){
+      if( data->ids[i] == id ){
+	switch( data->stype[i] ){
+	case 'I':
+	  DLALIGN(data->ptr,offset,INT_ALIGN);
+	  break;
+	case 'L':
+	  DLALIGN(data->ptr,offset,LONG_ALIGN);
+	  break;
+	case 'P':
+	  DLALIGN(data->ptr,offset,VOIDP_ALIGN);
+	  break;
+	case 'D':
+	  DLALIGN(data->ptr,offset,DOUBLE_ALIGN);
+	  break;
+	case 'F':
+	  DLALIGN(data->ptr,offset,FLOAT_ALIGN);
+	  break;
+	case 'C':
+	  break;
+	case 'H':
+	  DLALIGN(data->ptr,offset,SHORT_ALIGN);
+	  break;
+	default:
+	  raise(rb_eDLTypeError, "unsupported type '%c'", data->stype[i]);
+	};
+	memimg = ary2cary(data->stype[i], val, &memsize);
+	memcpy(data->ptr + offset, memimg, memsize);
+	return val;
+      };
+      switch( data->stype[i] ){
+      case 'I':
+      case 'i':
+	offset += sizeof(int) * data->ssize[i];
+	break;
+      case 'L':
+      case 'l':
+	offset += sizeof(long) * data->ssize[i];
+	break;
+      case 'P':
+      case 'p':
+	offset += sizeof(void*) * data->ssize[i];
+	break;
+      case 'D':
+      case 'd':
+	offset += sizeof(double) * data->ssize[i];
+	break;
+      case 'F':
+      case 'f':
+	offset += sizeof(float) * data->ssize[i];
+	break;
+      case 'C':
+      case 'c':
+	offset += sizeof(char) * data->ssize[i];
+	break;
+      case 'H':
+      case 'h':
+	offset += sizeof(short) * data->ssize[i];
+	break;
+      default:
+	raise(rb_eDLTypeError, "unsupported type '%c'", data->stype[i]);
+      };
+    };
+    return val;
+    /* break; */
+  case DLPTR_CTYPE_UNION:
+    for( i=0; i < data->ids_num; i++ ){
+      if( data->ids[i] == id ){
+	switch( data->stype[i] ){
+	case 'I': case 'i':
+	  memsize = sizeof(int) * data->ssize[i];
+	  break;
+	case 'L': case 'l':
+	  memsize = sizeof(long) * data->ssize[i];
+	  break;
+	case 'P': case 'p':
+	  memsize = sizeof(void*) * data->ssize[i];
+	  break;
+	case 'F': case 'f':
+	  memsize = sizeof(float) * data->ssize[i];
+	  break;
+	case 'D': case 'd':
+	  memsize = sizeof(double) * data->ssize[i];
+	  break;
+	case 'C': case 'c':
+	  memsize = sizeof(char) * data->ssize[i];
+	  break;
+	case 'H': case 'h':
+	  memsize = sizeof(short) * data->ssize[i];
+	  break;
+	default:
+	  raise(rb_eDLTypeError, "unsupported type '%c'", data->stype[i]);
+	};
+	memimg = ary2cary(data->stype[i], val, NULL);
+	memcpy(data->ptr, memimg, memsize);
+      };
+    };
+    return val;
+    /* break; */
+  };
+
+  rb_raise(rb_eNameError, "undefined key `%s' for %s",
+	   rb_id2name(id), rb_class2name(CLASS_OF(self)));
+
+  return Qnil;
+};
+
+VALUE
+rb_dlptr_size(int argc, VALUE argv[], VALUE self)
+{
+  VALUE size;
+
+  switch( rb_scan_args(argc, argv, "01", &size) ){
+  case 0:
+    return DLLONG2NUM(RDLPTR(self)->size);
+  case 1:
+    RDLPTR(self)->size = DLNUM2LONG(size);
+    return size;
+  };
+};
+
+static VALUE
+dlmem_each_i(VALUE assoc, void *data)
+{
+  VALUE key, val;
+  key = rb_ary_entry(assoc, 0);
+  val = rb_ary_entry(assoc, 1);
+  rb_yield(rb_assoc_new(key,(VALUE)DLNUM2LONG(val)));
+  return Qnil;
+};
+
+VALUE
+rb_dlmem_each(VALUE self)
+{
+  rb_iterate(rb_each, DLMemoryTable, dlmem_each_i, 0);
+  return Qnil;
+};
+
+void
+Init_dlptr()
+{
+  rb_cDLPtrData = rb_define_class_under(rb_mDL, "PtrData", rb_cData);
+  rb_define_singleton_method(rb_cDLPtrData, "new", rb_dlptr_s_new, -1);
+  rb_define_singleton_method(rb_cDLPtrData, "alloc", rb_dlptr_s_alloc, -1);
+  rb_define_method(rb_cDLPtrData, "initialize", rb_dlptr_init, -1);
+  rb_define_method(rb_cDLPtrData, "free=", rb_dlptr_free_set, 1);
+  rb_define_method(rb_cDLPtrData, "free",  rb_dlptr_free_get, 0);
+  rb_define_method(rb_cDLPtrData, "to_i",  rb_dlptr_to_i, 0);
+  rb_define_method(rb_cDLPtrData, "ptr",   rb_dlptr_ptr, 0);
+  rb_define_method(rb_cDLPtrData, "+@", rb_dlptr_ptr, 0);
+  rb_define_method(rb_cDLPtrData, "ref",   rb_dlptr_ref, 0);
+  rb_define_method(rb_cDLPtrData, "-@", rb_dlptr_ref, 0);
+  rb_define_method(rb_cDLPtrData, "null?", rb_dlptr_null_p, 0);
+  rb_define_method(rb_cDLPtrData, "to_a", rb_dlptr_to_array, -1);
+  rb_define_method(rb_cDLPtrData, "to_s", rb_dlptr_to_s, -1);
+  rb_define_method(rb_cDLPtrData, "to_str", rb_dlptr_to_str, -1);
+  rb_define_method(rb_cDLPtrData, "inspect", rb_dlptr_inspect, 0);
+  rb_define_method(rb_cDLPtrData, "<=>", rb_dlptr_cmp, 1);
+  rb_define_method(rb_cDLPtrData, "==", rb_dlptr_eql, 1);
+  rb_define_method(rb_cDLPtrData, "eql?", rb_dlptr_eql, 1);
+  rb_define_method(rb_cDLPtrData, "+", rb_dlptr_plus, 1);
+  rb_define_method(rb_cDLPtrData, "-", rb_dlptr_minus, 1);
+  rb_define_method(rb_cDLPtrData, "cast!", rb_dlptr_cast, -1);
+  rb_define_method(rb_cDLPtrData, "define_data_type",
+		   rb_dlptr_define_data_type, -1);
+  rb_define_method(rb_cDLPtrData, "struct!", rb_dlptr_define_struct, -1);
+  rb_define_method(rb_cDLPtrData, "union!",  rb_dlptr_define_union,  -1);
+  rb_define_method(rb_cDLPtrData, "data_type", rb_dlptr_get_data_type, 0);
+  rb_define_method(rb_cDLPtrData, "[]", rb_dlptr_aref, -1);
+  rb_define_method(rb_cDLPtrData, "[]=", rb_dlptr_aset, -1);
+  rb_define_method(rb_cDLPtrData, "size", rb_dlptr_size, -1);
+  rb_define_method(rb_cDLPtrData, "size=", rb_dlptr_size, -1);
+
+  rb_mDLMemorySpace = rb_define_module_under(rb_mDL, "MemorySpace");
+  DLMemoryTable = rb_hash_new();
+  rb_define_const(rb_mDLMemorySpace, "MemoryTable", DLMemoryTable);
+  rb_define_module_function(rb_mDLMemorySpace, "each", rb_dlmem_each, 0);
+};
diff --git a/ext/dl/sample/drives.rb b/ext/dl/sample/drives.rb
new file mode 100644
index 0000000000..8a590404b1
--- /dev/null
+++ b/ext/dl/sample/drives.rb
@@ -0,0 +1,70 @@
+# -*- ruby -*-
+# drives.rb -- find existing drives and show the drive type.
+
+require 'dl'
+require 'dl/import'
+
+module Kernel32
+  extend DL::Importable
+
+  dlload "kernel32"
+
+  extern "long GetLogicalDrives()"
+  extern "int GetDriveType(char*)"
+  extern "long GetDiskFreeSpace(char*, long ref, long ref, long ref, long ref)"
+end
+
+include Kernel32
+
+buff = Kernel32.getLogicalDrives()
+
+i = 0
+ds = []
+while( i < 26 )
+  mask = (1 << i)
+  if( buff & mask > 0 )
+    ds.push((65+i).chr)
+  end
+  i += 1
+end
+
+=begin
+From the cygwin's /usr/include/w32api/winbase.h:
+#define DRIVE_UNKNOWN 0
+#define DRIVE_NO_ROOT_DIR 1
+#define DRIVE_REMOVABLE 2
+#define DRIVE_FIXED 3
+#define DRIVE_REMOTE 4
+#define DRIVE_CDROM 5
+#define DRIVE_RAMDISK 6
+=end
+
+types = [
+  "unknown",
+  "no root dir",
+  "Removable",
+  "Fixed", 
+  "Remote",
+  "CDROM",
+  "RAM",
+]
+print("Drive : Type (Free Space/Available Space)\n")
+ds.each{|d|
+  t = Kernel32.getDriveType(d + ":\\")
+  Kernel32.getDiskFreeSpace(d + ":\\", 0, 0, 0, 0)
+  _,sec_per_clus,byte_per_sec,free_clus,total_clus = Kernel32._args_
+  fbytes = sec_per_clus * byte_per_sec * free_clus
+  tbytes = sec_per_clus * byte_per_sec * total_clus
+  unit = "B"
+  if( fbytes > 1024 && tbytes > 1024 )
+    fbytes = fbytes / 1024
+    tbytes = tbytes / 1024
+    unit = "K"
+  end
+  if( fbytes > 1024 && tbytes > 1024 )
+    fbytes = fbytes / 1024
+    tbytes = tbytes / 1024
+    unit = "M"
+  end
+  print("#{d} : #{types[t]} (#{fbytes} #{unit}/#{tbytes} #{unit})\n")
+}
diff --git a/ext/dl/sample/getch.rb b/ext/dl/sample/getch.rb
new file mode 100644
index 0000000000..3f7261c979
--- /dev/null
+++ b/ext/dl/sample/getch.rb
@@ -0,0 +1,5 @@
+require 'dl'
+
+crtdll = DL::dlopen("crtdll")
+getch  = crtdll['_getch', 'L']
+print(getch.call, "\n")
diff --git a/ext/dl/sample/libc.rb b/ext/dl/sample/libc.rb
new file mode 100644
index 0000000000..c88fc687f2
--- /dev/null
+++ b/ext/dl/sample/libc.rb
@@ -0,0 +1,84 @@
+require 'dl'
+
+module LIBC
+  begin
+    LIB = DL.dlopen('libc.so.6')
+  rescue RuntimeError
+    LIB = DL.dlopen('libc.so.5')
+  end
+
+  SYM = {
+    :atoi    => LIB['atoi', 'IS'],
+    :isdigit => LIB['isdigit', 'II'],
+  }
+
+  def atoi(str)
+    r,rs = SYM[:atoi].call(str)
+    return r
+  end
+
+  def isdigit(c)
+    r,rs = SYM[:isdigit].call(c)
+    return (r != 0)
+  end
+end
+
+module LIBC
+  SYM[:strcat] = LIB['strcat', 'SsS']
+  def strcat(str1,str2)
+    r,rs = SYM[:strcat].call(str1 + "\0#{str2}",str2)
+    return rs[0]
+  end
+end
+
+module LIBC
+  SYM[:fopen] = LIB['fopen', 'PSS']
+  SYM[:fclose] = LIB['fclose', '0P']
+  SYM[:fgetc] = LIB['fgetc', 'IP']
+
+  def fopen(filename, mode)
+    r,rs = SYM[:fopen].call(filename, mode)
+    return r
+  end
+
+  def fclose(ptr)
+    SYM[:fclose].call(ptr)
+    return nil
+  end
+
+  def fgetc(ptr)
+    r,rs = SYM[:fgetc].call(ptr)
+    return r
+  end
+end
+
+module LIBC
+  SYM[:strlen] = LIB['strlen', 'IP']
+  def strlen(str)
+    r,rs = SYM[:strlen].call(str)
+    return r
+  end
+end
+
+$cb1 = DL.set_callback('IPP', 0){|ptr1, ptr2|
+  str1 = ptr1.ptr.to_s
+  str2 = ptr2.ptr.to_s
+  str1 <=> str2
+}
+
+module LIBC
+  SYM[:qsort] = LIB['qsort', '0aIIP']
+  def qsort(ary, comp)
+    len = ary.length
+    r,rs = SYM[:qsort].call(ary, len, DL.sizeof('P'), comp)
+    return rs[0].to_a('S', len)
+  end
+end
+
+include LIBC
+
+p atoi("10")
+p isdigit(?1)
+p isdigit(?a)
+p strcat("a", "b")
+p qsort(["a","c","b"],$cb1)
diff --git a/ext/dl/sample/msgbox.rb b/ext/dl/sample/msgbox.rb
new file mode 100644
index 0000000000..091e646091
--- /dev/null
+++ b/ext/dl/sample/msgbox.rb
@@ -0,0 +1,19 @@
+# This script works on Windows.
+
+require 'dl'
+
+User32 = DL.dlopen("user32")
+Kernel32 = DL.dlopen("kernel32")
+
+MB_OK = 0
+MB_OKCANCEL = 1
+
+message_box = User32['MessageBoxA', 'ILSSI']
+r,rs = message_box.call(0, 'ok?', 'error', MB_OKCANCEL)
+
+case r
+when 1
+  print("OK!\n")
+when 2
+  print("Cancel!\n")
+end
diff --git a/ext/dl/sample/msgbox2.rb b/ext/dl/sample/msgbox2.rb
new file mode 100644
index 0000000000..e49846cc5e
--- /dev/null
+++ b/ext/dl/sample/msgbox2.rb
@@ -0,0 +1,18 @@
+# This script works on Windows.
+
+require 'dl/win32'
+
+MB_OK = 0
+MB_OKCANCEL = 1
+
+message_box = Win32API.new("user32",'MessageBoxA', 'ISSI', 'I')
+r = message_box.call(0, 'ok?', 'error', MB_OKCANCEL)
+
+case r
+when 1
+  print("OK!\n")
+when 2
+  print("Cancel!\n")
+else
+  p r
+end
diff --git a/ext/dl/sample/stream.rb b/ext/dl/sample/stream.rb
new file mode 100644
index 0000000000..179836999d
--- /dev/null
+++ b/ext/dl/sample/stream.rb
@@ -0,0 +1,87 @@
+# -*- ruby -*-
+# Display a file name and stream names of a file with those size.
+
+require 'dl'
+require 'dl/import'
+
+module NTFS
+  extend DL::Importable
+
+  dlload "kernel32.dll"
+
+  OPEN_EXISTING         = 3
+  GENERIC_READ          = 0x80000000
+  BACKUP_DATA           = 0x00000001
+  BACKUP_ALTERNATE_DATA = 0x00000004
+  FILE_SHARE_READ       = 0x00000001
+  FILE_FLAG_BACKUP_SEMANTICS = 0x02000000
+
+  typealias "LPSECURITY_ATTRIBUTES", "void*"
+
+  extern "BOOL BackupRead(HANDLE, PBYTE, DWORD, PDWORD, BOOL, BOOL, PVOID)"
+  extern "BOOL BackupSeek(HANDLE, DWORD, DWORD, PDWORD, PDWORD, PVOID)"
+  extern "BOOL CloseHandle(HANDLE)"
+  extern "HANDLE CreateFile(LPCSTR, DWORD, DWORD, LPSECURITY_ATTRIBUTES,
+                            DWORD, DWORD, HANDLE)"
+
+  module_function
+
+  def streams(filename)
+    status = []
+    h = createFile(filename,GENERIC_READ,FILE_SHARE_READ,nil,
+		   OPEN_EXISTING,FILE_FLAG_BACKUP_SEMANTICS,0)
+    if( h != 0 )
+      begin
+	# allocate the memory for backup data used in backupRead().
+	data = DL.malloc(DL.sizeof("L5"))
+	data.struct!("LLLLL", :id, :attrs, :size_low, :size_high, :name_size)
+
+	# allocate memories for references to long values used in backupRead().
+	context = DL.malloc(DL.sizeof("L"))
+	lval = DL.malloc(DL.sizeof("L"))
+
+	while( backupRead(h, data, data.size, lval, false, false, context) )
+	  size = data[:size_low] + (data[:size_high] << (DL.sizeof("I") * 8))
+	  case data[:id]
+	  when BACKUP_ALTERNATE_DATA
+	    stream_name = DL.malloc(data[:name_size])
+	    backupRead(h, stream_name, stream_name.size,
+		       lval, false, false, context)
+	    name = stream_name[0, stream_name.size]
+	    name.tr!("\000","")
+	    if( name =~ /^:(.*?):.*$/ )
+	      status.push([$1,size])
+	    end
+	  when BACKUP_DATA
+	    status.push([nil,size])
+	  else
+	    raise(RuntimeError, "unknown data type #{data[:id]}.")
+	  end
+	  l1 = DL.malloc(DL.sizeof("L"))
+	  l2 = DL.malloc(DL.sizeof("L"))
+	  if( !backupSeek(h, data[:size_low], data[:size_high], l1, l2, context) )
+	    break
+	  end
+	end
+      ensure
+	backupRead(h, nil, 0, lval, true, false, context)
+	closeHandle(h)
+      end
+      return status
+    else
+      raise(RuntimeError, "can't open #{filename}.\n")
+    end
+  end
+end
+
+ARGV.each{|filename|
+  if( File.exist?(filename) )
+    NTFS.streams(filename).each{|name,size|
+      if( name )
+	print("#{filename}:#{name}\t#{size}bytes\n")
+      else
+	print("#{filename}\t#{size}bytes\n")
+      end
+    }
+  end
+}
diff --git a/ext/dl/sym.c b/ext/dl/sym.c
new file mode 100644
index 0000000000..683092ae7b
--- /dev/null
+++ b/ext/dl/sym.c
@@ -0,0 +1,771 @@
+/* -*- C -*-
+ * $Id$
+ */
+
+#include <ruby.h>
+#include "dl.h"
+
+VALUE rb_cDLSymbol;
+
+#ifndef HAVE_RB_STR_CAT2
+static VALUE
+rb_str_cat2(VALUE str, const char *s)
+{
+  return rb_str_cat(str, s, strlen(s));
+}
+#endif
+
+static const char *
+char2type(int ch)
+{
+  switch (ch) {
+  case '0':
+    return "void";
+  case 'P':
+    return "void *";
+  case 'p':
+    return "void *";
+  case 'C':
+    return "char";
+  case 'c':
+    return "char *";
+  case 'H':
+    return "short";
+  case 'h':
+    return "short *";
+  case 'I':
+    return "int";
+  case 'i':
+    return "int *";
+  case 'L':
+    return "long";
+  case 'l':
+    return "long *";
+  case 'F':
+    return "double";
+  case 'f':
+    return "double *";
+  case 'D':
+    return "double";
+  case 'd':
+    return "double *";
+  case 'S':
+    return "const char *";
+  case 's':
+    return "char *";
+  case 'A':
+    return "[]";
+  case 'a':
+    return "[]"; /* ?? */
+  };
+  return NULL;
+};
+
+void
+dlsym_free(struct sym_data *data)
+{
+  if( data->name ){
+    DEBUG_CODE({
+      printf("dlsym_free(): free(data->name:%s)\n",data->name);
+    });
+    free(data->name);
+  };
+  if( data->type ){
+    DEBUG_CODE({
+      printf("dlsym_free(): free(data->type:%s)\n",data->type);
+    });
+    free(data->type);
+  };
+};
+
+VALUE
+rb_dlsym_new(void (*func)(), const char *name, const char *type)
+{
+  VALUE val;
+  struct sym_data *data;
+  const char *ptype;
+
+  if( !type || !type[0] ){
+    return rb_dlptr_new((void*)func, 0, 0);
+  };
+
+  for( ptype = type; *ptype; ptype ++ ){
+    if( ! char2type(*ptype) ){
+      rb_raise(rb_eDLTypeError, "unknown type specifier '%c'", *ptype);
+    };
+  };
+
+  if( func ){
+    val = Data_Make_Struct(rb_cDLSymbol, struct sym_data, 0, dlsym_free, data);
+    data->func = func;
+    data->name = name ? strdup(name) : NULL;
+    data->type = type ? strdup(type) : NULL;
+    data->len  = type ? strlen(type) : 0;
+#ifndef USE_INLINE_ASM
+    if( data->len - 1 > MAX_ARG ){
+      rb_raise(rb_eDLError, "maximum number of arguments is %d.", MAX_ARG);
+    };
+#endif
+  }
+  else{
+    val = Qnil;
+  };
+
+  return val;
+};
+
+freefunc_t
+rb_dlsym2csym(VALUE val)
+{
+  struct sym_data *data;
+  void (*func)();
+
+  if( rb_obj_is_kind_of(val, rb_cDLSymbol) ){
+    Data_Get_Struct(val, struct sym_data, data);
+    func = data->func;
+  }
+  else if( val == Qnil ){
+    func = NULL;
+  }
+  else{
+    rb_raise(rb_eTypeError, "DL::Symbol was expected");
+  };
+
+  return func;
+};
+
+VALUE
+rb_dlsym_s_new(int argc, VALUE argv[], VALUE self)
+{
+  VALUE addr, name, type;
+  VALUE val;
+  void *saddr;
+  const char *sname, *stype;
+
+  switch( rb_scan_args(argc, argv, "12", &addr, &name, &type) ){
+  case 3:
+    break;
+  case 2:
+    type = Qnil;
+    break;
+  case 1:
+    name = Qnil;
+    type = Qnil;
+  };
+
+  saddr = (void*)(DLNUM2LONG(rb_Integer(addr)));
+  sname = (name == Qnil) ? NULL : STR2CSTR(name);
+  stype = (type == Qnil) ? NULL : STR2CSTR(type);
+
+  val = rb_dlsym_new(saddr, sname, stype);
+
+  if( val != Qnil ){
+    rb_obj_call_init(val, argc, argv);
+  };
+
+  return val;
+};
+
+VALUE
+rb_dlsym_initialize(int argc, VALUE argv[], VALUE self)
+{
+  return Qnil;
+};
+
+VALUE
+rb_s_dlsym_char2type(VALUE self, VALUE ch)
+{
+  const char *type;
+
+  type = char2type(STR2CSTR(ch)[0]);
+
+  if (type == NULL)
+    return Qnil;
+  else
+    return rb_str_new2(type);
+};
+
+VALUE
+rb_dlsym_name(VALUE self)
+{
+  struct sym_data *sym;
+
+  Data_Get_Struct(self, struct sym_data, sym);
+  return sym->name ? rb_tainted_str_new2(sym->name) : Qnil;
+};
+
+VALUE
+rb_dlsym_proto(VALUE self)
+{
+  struct sym_data *sym;
+
+  Data_Get_Struct(self, struct sym_data, sym);
+  return sym->type ? rb_tainted_str_new2(sym->type) : Qnil;
+};
+
+VALUE
+rb_dlsym_cproto(VALUE self)
+{
+  struct sym_data *sym;
+  const char *ptype, *typestr;
+  size_t len;
+  VALUE val;
+
+  Data_Get_Struct(self, struct sym_data, sym);
+
+  ptype = sym->type;
+
+  if( ptype ){
+    typestr = char2type(*ptype++);
+    len = strlen(typestr);
+    
+    val = rb_tainted_str_new(typestr, len);
+    if (typestr[len - 1] != '*')
+      rb_str_cat(val, " ", 1);
+
+    if( sym->name ){
+      rb_str_cat2(val, sym->name);
+    }
+    else{
+      rb_str_cat2(val, "(null)");
+    };
+    rb_str_cat(val, "(", 1);
+    
+    while (*ptype) {
+      const char *ty = char2type(*ptype++);
+      rb_str_cat2(val, ty);
+      if (*ptype)
+	rb_str_cat(val, ", ", 2);
+    }
+
+    rb_str_cat(val, ");", 2);
+  }
+  else{
+    val = rb_tainted_str_new2("void (");
+    if( sym->name ){
+      rb_str_cat2(val, sym->name);
+    }
+    else{
+      rb_str_cat2(val, "(null)");
+    };
+    rb_str_cat2(val, ")()");
+  };
+
+  return val;
+};
+
+VALUE
+rb_dlsym_inspect(VALUE self)
+{
+  VALUE proto;
+  VALUE val;
+  char  *str;
+  int str_size;
+  struct sym_data *sym;
+
+  Data_Get_Struct(self, struct sym_data, sym);
+  proto = rb_dlsym_cproto(self);
+
+  str_size = RSTRING(proto)->len + 100;
+  str = dlmalloc(str_size);
+  snprintf(str, str_size - 1,
+	   "#<DL::Symbol:0x%x func=0x%x '%s'>",
+	   sym, sym->func, STR2CSTR(proto));
+  val = rb_tainted_str_new2(str);
+  dlfree(str);
+
+  return val;
+};
+
+
+VALUE
+rb_dlsym_call(int argc, VALUE argv[], VALUE self)
+{
+  struct sym_data *sym;
+  ANY_TYPE *args;
+  ANY_TYPE *dargs;
+  ANY_TYPE ret;
+  int   *dtypes;
+  VALUE val;
+  VALUE dvals;
+  int i;
+  long ftype;
+  void *func;
+
+  Data_Get_Struct(self, struct sym_data, sym);
+  DEBUG_CODE({
+    printf("rb_dlsym_call(): type = '%s', func = 0x%x\n", sym->type, sym->func);
+  });
+  if( (sym->len - 1) != argc ){
+    rb_raise(rb_eArgError, "%d arguments are needed", sym->len - 1);
+  };
+
+  ftype = 0;
+  dvals = Qnil;
+
+  args = ALLOC_N(ANY_TYPE, sym->len - 1);
+  dargs = ALLOC_N(ANY_TYPE, sym->len - 1);
+  dtypes = ALLOC_N(int, sym->len - 1);
+#define FREE_ARGS {xfree(args); xfree(dargs); xfree(dtypes);}
+
+  for( i = sym->len - 2; i >= 0; i-- ){
+    dtypes[i] = 0;
+
+    switch( sym->type[i+1] ){
+    case 'p':
+      dtypes[i] = 'p';
+    case 'P':
+      {
+	struct ptr_data *data;
+	VALUE pval;
+
+	if( argv[i] == Qnil ){
+	  ANY2P(args[i]) = DLVOIDP(0);
+	}
+	else{
+	  if( rb_obj_is_kind_of(argv[i], rb_cDLPtrData) ){
+	    pval = argv[i];
+	  }
+	  else{
+	    pval = rb_funcall(argv[i], rb_intern("to_ptr"), 0);
+	    if( !rb_obj_is_kind_of(pval, rb_cDLPtrData) ){
+	      rb_raise(rb_eDLTypeError, "unexpected type of argument #%d", i);
+	    };
+	  };
+	  Data_Get_Struct(pval, struct ptr_data, data);
+	  ANY2P(args[i]) = DLVOIDP(data->ptr);
+	};
+      };
+      PUSH_P(ftype);
+      break;
+    case 'a':
+      dtypes[i] = 'a';
+    case 'A':
+      if( argv[i] == Qnil ){
+	ANY2P(args[i]) = DLVOIDP(0);
+      }
+      else{
+	ANY2P(args[i]) = DLVOIDP(rb_ary2cary(0, argv[i], NULL));
+      };
+      PUSH_P(ftype);
+      break;
+    case 'C':
+      ANY2C(args[i]) = DLCHAR(NUM2CHR(argv[i]));
+      PUSH_C(ftype);
+      break;
+    case 'c':
+      ANY2C(dargs[i]) = DLCHAR(NUM2CHR(argv[i]));
+      ANY2P(args[i]) = DLVOIDP(&(ANY2C(dargs[i])));
+      dtypes[i] = 'c';
+      PUSH_P(ftype);
+      break;
+    case 'H':
+      ANY2H(args[i]) = DLSHORT(NUM2CHR(argv[i]));
+      PUSH_C(ftype);
+      break;
+    case 'h':
+      ANY2H(dargs[i]) = DLSHORT(NUM2CHR(argv[i]));
+      ANY2P(args[i]) = DLVOIDP(&(ANY2H(dargs[i])));
+      dtypes[i] = 'h';
+      PUSH_P(ftype);
+      break;
+    case 'I':
+      ANY2I(args[i]) = DLINT(NUM2INT(argv[i]));
+      PUSH_I(ftype);
+      break;
+    case 'i':
+      ANY2I(dargs[i]) = DLINT(NUM2INT(argv[i]));
+      ANY2P(args[i]) = DLVOIDP(&(ANY2I(dargs[i])));
+      dtypes[i] = 'i';
+      PUSH_P(ftype);
+      break;
+    case 'L':
+      ANY2L(args[i]) = DLNUM2LONG(argv[i]);
+      PUSH_L(ftype);
+      break;
+    case 'l':
+      ANY2L(dargs[i]) = DLNUM2LONG(argv[i]);
+      ANY2P(args[i]) = DLVOIDP(&(ANY2L(dargs[i])));
+      dtypes[i] = 'l';
+      PUSH_P(ftype);
+      break;
+    case 'F':
+      Check_Type(argv[i], T_FLOAT);
+      ANY2F(args[i]) = DLFLOAT(RFLOAT(argv[i])->value);
+      PUSH_F(ftype);
+      break;
+    case 'f':
+      Check_Type(argv[i], T_FLOAT);
+      ANY2F(dargs[i]) = DLFLOAT(RFLOAT(argv[i])->value);
+      ANY2P(args[i]) = DLVOIDP(&(ANY2F(dargs[i])));
+      dtypes[i] = 'f';
+      PUSH_P(ftype);
+      break;
+    case 'D':
+      Check_Type(argv[i], T_FLOAT);
+      ANY2D(args[i]) = RFLOAT(argv[i])->value;
+      PUSH_D(ftype);
+      break;
+    case 'd':
+      Check_Type(argv[i], T_FLOAT);
+      ANY2D(dargs[i]) = RFLOAT(argv[i])->value;
+      ANY2P(args[i]) = DLVOIDP(&(ANY2D(dargs[i])));
+      dtypes[i] = 'd';
+      PUSH_P(ftype);
+      break;
+    case 'S':
+      if( argv[i] == Qnil ){
+	ANY2S(args[i]) = DLSTR(0);
+      }
+      else{
+	ANY2S(args[i]) = DLSTR(STR2CSTR(argv[i]));
+      };
+      PUSH_P(ftype);
+      break;
+    case 's':
+      if( argv[i] == Qnil ){
+	raise(rb_eDLError, "#%d must be a string",i);
+      };
+      ANY2S(args[i]) = DLSTR(dlmalloc(RSTRING(argv[i])->len + 1));
+      memcpy((char*)(ANY2S(args[i])), STR2CSTR(argv[i]), RSTRING(argv[i])->len + 1);
+      dtypes[i] = 's';
+      PUSH_P(ftype);
+      break;
+    default:
+      FREE_ARGS;
+      rb_raise(rb_eDLTypeError,
+	       "unknown type '%c' of the return value.",
+	       sym->type[i+1]);
+    };
+  };
+
+  switch( sym->type[0] ){
+  case '0':
+    PUSH_0(ftype);
+    break;
+  case 'P':
+  case 'p':
+  case 'S':
+  case 's':
+  case 'A':
+  case 'a':
+    PUSH_P(ftype);
+    break;
+  case 'C':
+  case 'c':
+    PUSH_C(ftype);
+    break;
+  case 'H':
+  case 'h':
+    PUSH_H(ftype);
+    break;
+  case 'I':
+  case 'i':
+    PUSH_I(ftype);
+    break;
+  case 'L':
+  case 'l':
+    PUSH_L(ftype);
+    break;
+  case 'F':
+  case 'f':
+    PUSH_F(ftype);
+    break;
+  case 'D':
+  case 'd':
+    PUSH_D(ftype);
+    break;
+  default:
+    FREE_ARGS;
+    rb_raise(rb_eDLTypeError,
+	     "unknown type `%c' of the return value.",
+	     sym->type[0]);
+  };
+
+  func = sym->func;
+
+#ifdef USE_INLINE_ASM
+  ASM_START(sym->type);
+  for( i = sym->len - 2; i >= 0; i-- ){
+    switch( sym->type[i+1] ){
+    case 'p':
+    case 'P':
+      ASM_PUSH_P(ANY2P(args[i]));
+      break;
+    case 'a':
+    case 'A':
+      ASM_PUSH_P(ANY2P(args[i]));
+      break;
+    case 'C':
+      ASM_PUSH_C(ANY2C(args[i]));
+      break;
+    case 'c':
+      ASM_PUSH_P(ANY2P(args[i]));
+      break;
+    case 'H':
+      ASM_PUSH_H(ANY2H(args[i]));
+      break;
+    case 'h':
+      ASM_PUSH_P(ANY2P(args[i]));
+      break;
+    case 'I':
+      ASM_PUSH_I(ANY2I(args[i]));
+      break;
+    case 'i':
+      ASM_PUSH_P(ANY2P(args[i]));
+      break;
+    case 'L':
+      ASM_PUSH_L(ANY2L(args[i]));
+      break;
+    case 'l':
+      ASM_PUSH_P(ANY2P(args[i]));
+      break;
+    case 'F':
+      ASM_PUSH_F(ANY2F(args[i]));
+      break;
+    case 'f':
+      ASM_PUSH_P(ANY2P(args[i]));
+      break;
+    case 'D':
+      ASM_PUSH_D(ANY2D(args[i]));
+      break;
+    case 'd':
+      ASM_PUSH_P(ANY2P(args[i]));
+      break;
+    case 'S':
+    case 's':
+      ASM_PUSH_P(ANY2S(args[i]));
+      break;
+    };
+  }
+  ASM_END(sym->type);
+
+  {
+    switch( sym->type[0] ){
+    case '0':
+      {
+	void (*f)() = func;
+	f();
+      };
+      break;
+    case 'P':
+    case 'p':
+      {
+	void * (*f)() = func;
+	ret.p = f();
+      };
+      break;
+    case 'C':
+    case 'c':
+      {
+	char (*f)() = func;
+	ret.c = f();
+      };
+      break;
+    case 'H':
+    case 'h':
+      {
+	short (*f)() = func;
+	ret.h = f();
+      };
+      break;
+    case 'I':
+    case 'i':
+      {
+	int (*f)() = func;
+	ret.i = f();
+      };
+      break;
+    case 'L':
+    case 'l':
+      {
+	long (*f)() = func;
+	ret.l = f();
+      };
+      break;
+    case 'F':
+    case 'f':
+      {
+	float (*f)() = func;
+	ret.f = f();
+      };
+      break;
+    case 'D':
+    case 'd':
+      {
+	double (*f)() = func;
+	ret.d = f();
+      };
+      break;
+    case 'S':
+    case 's':
+      {
+	char * (*f)() = func;
+	ret.s = f();
+      };
+      break;
+    default:
+      FREE_ARGS;
+      rb_raise(rb_eDLTypeError, "unknown type `%c'", sym->type[0]);
+    };
+  };
+#else
+  switch(ftype){
+#include "call.func"
+  default:
+    FREE_ARGS;
+    rb_raise(rb_eDLTypeError, "unsupported function type `%s'", sym->type);
+  };
+#endif
+
+  switch( sym->type[0] ){
+  case '0':
+    val = Qnil;
+    break;
+  case 'P':
+    val = rb_dlptr_new((void*)(ANY2P(ret)), 0, 0);
+    break;
+  case 'p':
+    val = rb_dlptr_new((void*)(ANY2P(ret)), 0, dlfree);
+    break;
+  case 'C':
+  case 'c':
+    val = CHR2FIX((char)(ANY2C(ret)));
+    break;
+  case 'H':
+  case 'h':
+    val = INT2NUM((short)(ANY2H(ret)));
+    break;
+  case 'I':
+  case 'i':
+    val = INT2NUM((int)(ANY2I(ret)));
+    break;
+  case 'L':
+  case 'l':
+    val = DLLONG2NUM((long)(ANY2L(ret)));
+    break;
+  case 'F':
+  case 'f':
+    val = rb_float_new((double)(ANY2F(ret)));
+    break;
+  case 'D':
+  case 'd':
+    val = rb_float_new((double)(ANY2D(ret)));
+    break;
+  case 'S':
+    if( ANY2S(ret) ){
+      val = rb_tainted_str_new2((char*)(ANY2S(ret)));
+    }
+    else{
+      val = Qnil;
+    };
+    break;
+  case 's':
+    if( ANY2S(ret) ){
+      val = rb_tainted_str_new2((char*)(ANY2S(ret)));
+      DEBUG_CODE({
+	printf("dlfree(%s)\n",(char*)(ANY2S(ret)));
+      });
+      dlfree((void*)(ANY2S(ret)));
+    }
+    else{
+      val = Qnil;
+    };
+    break;
+  default:
+    FREE_ARGS;
+    rb_raise(rb_eDLTypeError, "unknown type `%c'", sym->type[0]);
+  };
+
+  dvals = rb_ary_new();
+  for( i = 0; i <= sym->len - 2; i++ ){
+    if( dtypes[i] ){
+      switch( dtypes[i] ){
+      case 'c':
+	rb_ary_push(dvals, CHR2FIX(*((char*)(ANY2P(args[i])))));
+	break;
+      case 'h':
+	rb_ary_push(dvals, INT2NUM(*((short*)(ANY2P(args[i])))));
+	break;
+      case 'i':
+	rb_ary_push(dvals, INT2NUM(*((int*)(ANY2P(args[i])))));
+	break;
+      case 'l':
+        rb_ary_push(dvals, DLLONG2NUM(*((long*)(ANY2P(args[i])))));
+        break;
+      case 'f':
+	rb_ary_push(dvals, rb_float_new(*((float*)(ANY2P(args[i])))));
+	break;
+      case 'd':
+	rb_ary_push(dvals, rb_float_new(*((double*)(ANY2P(args[i])))));
+	break;
+      case 'p':
+	rb_ary_push(dvals, rb_dlptr_new((void*)(ANY2P(args[i])), 0, 0));
+	break;
+      case 'a':
+	rb_ary_push(dvals, rb_dlptr_new((void*)ANY2P(args[i]), 0, 0));
+	break;
+      case 's':
+	rb_ary_push(dvals, rb_tainted_str_new2((char*)ANY2S(args[i])));
+	DEBUG_CODE({
+	  printf("dlfree(%s)\n",(char*)ANY2S(args[i]));
+	});
+	dlfree((void*)ANY2S(args[i]));
+	break;
+      default:
+	{
+	  char c = dtypes[i];
+	  FREE_ARGS;
+	  rb_raise(rb_eRuntimeError, "unknown argument type '%c'", i, c);
+	};
+      };
+    }
+    else{
+      switch( sym->type[i+1] ){
+      case 'A':
+	dlfree((void*)ANY2P(args[i]));
+	break;
+      };
+      rb_ary_push(dvals, argv[i]);
+    };
+  };
+
+#undef FREE_ARGS
+  return rb_assoc_new(val,dvals);
+};
+
+VALUE
+rb_dlsym_to_i(VALUE self)
+{
+  struct sym_data *sym;
+
+  Data_Get_Struct(self, struct sym_data, sym);
+  return DLLONG2NUM(sym);
+};
+
+VALUE
+rb_dlsym_to_ptr(VALUE self)
+{
+  struct sym_data *sym;
+
+  Data_Get_Struct(self, struct sym_data, sym);
+  return rb_dlptr_new(sym->func, sizeof(freefunc_t), 0);
+};
+
+void
+Init_dlsym()
+{
+  rb_cDLSymbol = rb_define_class_under(rb_mDL, "Symbol", rb_cData);
+  rb_define_singleton_method(rb_cDLSymbol, "new", rb_dlsym_s_new, -1);
+  rb_define_singleton_method(rb_cDLSymbol, "char2type", rb_s_dlsym_char2type, 1);
+  rb_define_method(rb_cDLSymbol, "initialize", rb_dlsym_initialize, -1);
+  rb_define_method(rb_cDLSymbol, "call", rb_dlsym_call, -1);
+  rb_define_method(rb_cDLSymbol, "[]",   rb_dlsym_call, -1);
+  rb_define_method(rb_cDLSymbol, "name", rb_dlsym_name, 0);
+  rb_define_method(rb_cDLSymbol, "proto", rb_dlsym_proto, 0);
+  rb_define_method(rb_cDLSymbol, "cproto", rb_dlsym_cproto, 0);
+  rb_define_method(rb_cDLSymbol, "inspect", rb_dlsym_inspect, 0);
+  rb_define_method(rb_cDLSymbol, "to_s", rb_dlsym_cproto, 0);
+  rb_define_method(rb_cDLSymbol, "to_ptr", rb_dlsym_to_ptr, 0);
+  rb_define_method(rb_cDLSymbol, "to_i", rb_dlsym_to_i, 0);
+};
diff --git a/ext/dl/test/libtest.def b/ext/dl/test/libtest.def
new file mode 100644
index 0000000000..d2585286e9
--- /dev/null
+++ b/ext/dl/test/libtest.def
@@ -0,0 +1,29 @@
+EXPORTS
+test_alloc_test_struct
+test_append
+test_arylen
+test_c2i
+test_call_func1
+test_callback1
+test_close
+test_d2f
+test_f2d
+test_fill_test_struct
+test_fill_test_union
+test_gets
+test_i2c
+test_init
+test_isucc
+test_lcc
+test_lsucc
+test_open
+test_strcat
+test_strlen
+test_succ
+test_data_init
+test_data_add
+test_data_print
+test_data_aref
+test_set_long_value
+test_get_long_value
+internal_long_value
diff --git a/ext/dl/test/test.c b/ext/dl/test/test.c
new file mode 100644
index 0000000000..c5ead79813
--- /dev/null
+++ b/ext/dl/test/test.c
@@ -0,0 +1,251 @@
+#include <stdio.h>
+#include <string.h>
+
+static char internal_string[] = "internal_string";
+long internal_long_value = 100;
+
+struct test_struct {
+  char c;
+  long l;
+};
+
+union test_union {
+  char c;
+  int  i;
+  long l;
+  void *p;
+};
+
+struct test_data {
+  char name[1024];
+  struct test_data *next;
+};
+
+long
+test_get_long_value()
+{
+  return internal_long_value;
+};
+
+void
+test_set_long_value(long l)
+{
+  internal_long_value = l;
+};
+
+void
+test_fill_test_struct(struct test_struct *ptr, char c, long l)
+{
+  ptr->c = c;
+  ptr->l = l;
+};
+
+void
+test_fill_test_union(union test_union *ptr, long l)
+{
+  ptr->l = l;
+};
+
+struct test_struct *
+test_alloc_test_struct(char c, long l)
+{
+  struct test_struct *data;
+
+  data = (struct test_struct *)malloc(sizeof(struct test_struct));
+  data->c = c;
+  data->l = l;
+
+  return data;
+};
+
+int
+test_c2i(char c)
+{
+  return (int)c;
+};
+
+char
+test_i2c(int i)
+{
+  return (char)i;
+};
+
+long
+test_lcc(char c1, char c2)
+{
+  return (long)(c1 + c2);
+};
+
+double
+test_f2d(float f)
+{
+  double d;
+  d = f;
+  return d;
+};
+
+float
+test_d2f(double d)
+{
+  float f;
+  f = d;
+  return f;
+};
+
+int
+test_strlen(const char *str)
+{
+  return strlen(str);
+};
+
+int
+test_isucc(int i)
+{
+  return (i+1);
+};
+
+long
+test_lsucc(long l)
+{
+  return (l+1);
+};
+
+void
+test_succ(long *l)
+{
+  (*l)++;
+};
+
+char *
+test_strcat(char *str1, const char *str2)
+{
+  return strcat(str1, str2);
+};
+
+int
+test_arylen(char *ary[])
+{
+  int i;
+  for( i=0; ary[i]; i++ ){};
+  return i;
+};
+
+void
+test_append(char *ary[], int len, char *astr)
+{
+  int i;
+  int size1,size2;
+  char *str;
+
+  size2 = strlen(astr);
+
+  for( i=0; i <= len - 1; i++ ){
+    size1 = strlen(ary[i]);
+    str = (char*)malloc(size1 + size2 + 1);
+    strcpy(str, ary[i]);
+    strcat(str, astr);
+    ary[i] = str;
+  };
+};
+
+void
+test_init(int *argc, char **argv[])
+{
+  int i;
+  printf("test_init(0x%x,0x%x)\n",argc,argv);
+  printf("\t*(0x%x) => %d\n",argc,*argc);
+  for( i=0; i < (*argc); i++ ){
+    printf("\t(*(0x%x)[%d]) => %s\n", argv, i, (*argv)[i]);
+  };
+};
+
+FILE *
+test_open(const char *filename, const char *mode)
+{
+  FILE *file;
+  file = fopen(filename,mode);
+  printf("test_open(%s,%s):0x%x\n",filename,mode,file);
+  return file;
+};
+
+void
+test_close(FILE *file)
+{
+  printf("test_close(0x%x)\n",file);
+  fclose(file);
+};
+
+char *
+test_gets(char *s, int size, FILE *f)
+{
+  return fgets(s,size,f);
+};
+
+typedef int callback1_t(int, char *);
+
+int
+test_callback1(int err, const char *msg)
+{
+  printf("internal callback function (err = %d, msg = '%s')\n",
+	 err, msg ? msg : "(null)");
+  return 1;
+};
+
+int
+test_call_func1(callback1_t *func)
+{
+  if( func ){
+    return (*func)(0, "this is test_call_func1.");
+  }
+  else{
+    printf("test_call_func1(func = 0)\n");
+    return -1;
+  }
+};
+
+struct test_data *
+test_data_init()
+{
+  struct test_data *data;
+
+  data = (struct test_data *)malloc(sizeof(struct test_data));
+  data->next = NULL;
+  memset(data->name, 0, 1024);
+
+  return data;
+};
+
+void
+test_data_add(struct test_data *list, const char *name)
+{
+  struct test_data *data;
+
+  data = (struct test_data *)malloc(sizeof(struct test_data));
+  strcpy(data->name, name);
+  data->next = list->next;
+  list->next = data;
+};
+
+void
+test_data_print(struct test_data *list)
+{
+  struct test_data *data;
+
+  for( data = list->next; data; data = data->next ){
+    printf("name = %s\n", data->name);
+  };
+};
+
+struct data *
+test_data_aref(struct test_data *list, int i)
+{
+  struct test_data *data;
+  int j;
+
+  for( data = list->next, j=0; data; data = data->next, j++ ){
+    if( i == j ){
+      return data;
+    };
+  };
+  return NULL;
+};
diff --git a/ext/dl/test/test.rb b/ext/dl/test/test.rb
new file mode 100644
index 0000000000..de9a9cc533
--- /dev/null
+++ b/ext/dl/test/test.rb
@@ -0,0 +1,272 @@
+# -*- ruby -*-
+
+require 'dl'
+require 'dl/import'
+
+def assert(label, ty, *conds)
+  cond = !conds.include?(false)
+  if( cond )
+    printf("succeed in `#{label}'\n")
+  else
+    case ty
+    when :may
+      printf("fail in `#{label}' ... expected\n")
+    when :must
+      printf("fail in `#{label}' ... unexpected\n")
+    when :raise
+      raise(RuntimeError, "fail in `#{label}'")
+    end
+  end
+end
+
+def debug(*xs)
+  if( $DEBUG )
+    xs.each{|x|
+      p x
+    }
+  end
+end
+
+print("VERSION       = #{DL::VERSION}\n")
+print("MAJOR_VERSION = #{DL::MAJOR_VERSION}\n")
+print("MINOR_VERSION = #{DL::MINOR_VERSION}\n")
+print("\n")
+print("MAX_ARG   = #{DL::MAX_ARG}\n")
+print("MAX_CBARG = #{DL::MAX_CBARG}\n")
+print("MAX_CBENT = #{DL::MAX_CBENT}\n")
+print("\n")
+print("DL::FREE = #{DL::FREE.inspect}\n")
+print("\n")
+
+$LIB = nil
+if( !$LIB && File.exist?("libtest.so") )
+  $LIB = "./libtest.so"
+end
+if( !$LIB && File.exist?("test/libtest.so") )
+  $LIB = "./test/libtest.so"
+end
+
+module LIBTest
+  extend DL::Importable
+
+  dlload($LIB)
+  extern "int test_c2i(char)"
+  extern "char test_i2c(int)"
+  extern "long test_lcc(char, char)"
+  extern "double test_f2d(float)"
+  extern "float test_d2f(double)"
+  extern "int test_strlen(char*)"
+  extern "int test_isucc(int)"
+  extern "long test_lsucc(long)"
+  extern "void test_succ(long *)"
+  extern "int test_arylen(int [])"
+  extern "void test_append(char*[], int, char *)"
+end
+
+DL.dlopen($LIB){|h|
+  c2i = h["test_c2i","IC"]
+  debug c2i
+  r,rs = c2i[?a]
+  debug r,rs
+  assert("c2i", :may, r == ?a)
+  assert("extern c2i", :must, r == LIBTest.test_c2i(?a))
+
+  i2c = h["test_i2c","CI"]
+  debug i2c
+  r,rs = i2c[?a]
+  debug r,rs
+  assert("i2c", :may, r == ?a)
+  assert("exern i2c", :must, r == LIBTest.test_i2c(?a))
+
+  lcc = h["test_lcc","LCC"]
+  debug lcc
+  r,rs = lcc[1,2]
+  assert("lcc", :may, r == 3)
+  assert("extern lcc", :must, r == LIBTest.test_lcc(1,2))
+
+  f2d = h["test_f2d","DF"]
+  debug f2d
+  r,rs = f2d[20.001]
+  debug r,rs
+  assert("f2d", :may, r.to_i == 20)
+  assert("extern f2d", :must, r = LIBTest.test_f2d(20.001))
+
+  d2f = h["test_d2f","FD"]
+  debug d2f
+  r,rs = d2f[20.001]
+  debug r,rs
+  assert("d2f", :may, r.to_i == 20)
+  assert("extern d2f", :must, r == LIBTest.test_d2f(20.001))
+
+  strlen = h["test_strlen","IS"]
+  debug strlen
+  r,rs = strlen["0123456789"]
+  debug r,rs
+  assert("strlen", :must, r == 10)
+  assert("extern strlen", :must, r == LIBTest.test_strlen("0123456789"))
+
+  isucc = h["test_isucc","II"]
+  debug isucc
+  r,rs = isucc[2]
+  debug r,rs
+  assert("isucc", :must, r == 3)
+  assert("extern isucc", :must, r == LIBTest.test_isucc(2))
+
+  lsucc = h["test_lsucc","LL"]
+  debug lsucc
+  r,rs = lsucc[10000000]
+  debug r,rs
+  assert("lsucc", :must, r == 10000001)
+  assert("extern lsucc", :must, r == LIBTest.test_lsucc(10000000))
+
+  succ = h["test_succ","0l"]
+  debug succ
+  r,rs = succ[0]
+  debug r,rs
+  assert("succ", :must, rs[0] == 1)
+  l = DL.malloc(DL.sizeof("L"))
+  l.struct!("L",:lval)
+  LIBTest.test_succ(l)
+  assert("extern succ", :must, rs[0] == l[:lval])
+
+  arylen = h["test_arylen","IA"]
+  debug arylen
+  r,rs = arylen[["a","b","c","d",nil]]
+  debug r,rs
+  assert("arylen", :must, r == 4)
+
+  arylen = h["test_arylen","IP"]
+  debug arylen
+  r,rs = arylen[["a","b","c","d",nil]]
+  debug r,rs
+  assert("arylen", :must, r == 4)
+  assert("extern arylen", :must, r == LIBTest.test_arylen(["a","b","c","d",nil]))
+
+  append = h["test_append","0aIS"]
+  debug append
+  r,rs = append[["a","b","c"],3,"x"]
+  debug r,rs
+  assert("append", :must, rs[0].to_a('S',3) == ["ax","bx","cx"])
+
+  LIBTest.test_append(["a","b","c"],3,"x")
+  assert("extern append", :must, rs[0].to_a('S',3) == LIBTest._args_[0].to_a('S',3))
+
+  strcat = h["test_strcat","SsS"]
+  debug strcat
+  r,rs = strcat["abc\0","x"]
+  debug r,rs
+  assert("strcat", :must, rs[0].to_s == "abcx")
+
+  init = h["test_init","0iP"]
+  debug init
+  argc = 3
+  argv = ["arg0","arg1","arg2"].to_ptr
+  r,rs = init[argc, argv.ref]
+  debug r,rs
+}
+
+
+h = DL.dlopen($LIB)
+
+sym_open = h["test_open", "PSS"]
+sym_gets = h["test_gets", "SsIP"]
+sym_close = h["test_close", "0P"]
+debug sym_open,sym_gets,sym_close
+
+line = "Hello world!\n"
+File.open("tmp.txt", "w"){|f|
+  f.print(line)
+}
+
+fp,rs = sym_open["tmp.txt", "r"]
+if( fp )
+  fp.free = sym_close
+  r,rs = sym_gets[" " * 256, 256, fp]
+  debug r,rs
+  assert("open,gets", :must, rs[0] == line)
+else
+  assert("open,gets", :must, line == nil)
+end
+File.unlink("tmp.txt")
+
+
+callback1 = h["test_callback1"]
+debug callback1
+r,rs = h["test_call_func1", "IP"][callback1]
+debug r,rs
+assert("callback1", :must, r == 1)
+
+
+callback2 = DL.set_callback("LLP", 0){|arg1,arg2|
+  ptr = arg2 # DL::PtrData.new(arg2)
+  msg = ptr.to_s
+  print("user defined callback function",
+	"(err = #{arg1}, msg = '#{msg}')\n")
+  2
+}
+debug callback2
+r,rs = h["test_call_func1", "IP"][callback2]
+debug r,rs
+assert("callback2", :must, r == 2)
+
+
+ptr = DL.malloc(DL.sizeof('CL'))
+ptr.struct!("CL", :c, :l)
+ptr["c"] = 0
+ptr["l"] = 0
+r,rs = h["test_fill_test_struct","0PIL"][ptr,100,1000]
+debug r,rs
+assert("fill_test_struct", :must, ptr["c"] == 100, ptr["l"] == 1000)
+assert("fill_test_struct", :must, ptr[:c] == 100, ptr[:l] == 1000) unless (Fixnum === :-)
+
+
+r,rs = h["test_alloc_test_struct", "PIL"][100,200]
+r.free = DL::FREE
+r.struct!("CL", :c, :l)
+assert("alloc_test_struct", :must, r["c"] == 100, r["l"] == 200)
+assert("alloc_test_struct", :must, r[:c] == 100, r[:l] == 200) unless (Fixnum === :-)
+
+ptr = h["test_strlen"]
+sym1 = DL::Symbol.new(ptr,"foo","0")
+sym2 = h["test_strlen","LS"]
+assert("Symbol.new", :must, ptr == sym1.to_ptr, sym1.to_ptr == sym2.to_ptr)
+
+set_val = h["test_set_long_value","0"]
+get_val = h["test_get_long_value","L"]
+lval = get_val[][0]
+ptr = h["internal_long_value"]
+ptr.struct!("l", :l)
+assert("get value", :must, ptr["l"] == lval)
+assert("get value", :must, ptr[:l] == lval) unless (Fixnum === :-)
+ptr["l"] = 200
+lval = get_val[][0]
+assert("set value", :must, ptr["l"] == lval)
+assert("set value", :must, ptr[:l] == lval) unless (Fixnum === :-)
+
+
+data_init = h["test_data_init", "P"]
+data_add  = h["test_data_add", "0PS"]
+data_print = h["test_data_print", "0P"]
+data_aref = h["test_data_aref", "PPI"]
+r,rs = data_init[]
+ptr = r
+data_add[ptr, "name1"]
+data_add[ptr, "name2"]
+data_add[ptr, "name3"]
+data_print[ptr]
+
+r,rs = data_aref[ptr, 1]
+ptr = r
+ptr.struct!("C1024P", :name, :next)
+assert("data_aref", :must,
+       ptr["name"].collect{|c| c.chr}.join.split("\0")[0] == "name2")
+assert("data_aref", :must,
+       ptr["name"].collect{|c| c.chr}.join.split("\0")[0] == "name2") unless (Fixnum === :-)
+ptr = ptr["next"]
+ptr.struct!("C1024P", :name, :next)
+assert("data_aref", :must,
+       ptr["name"].collect{|c| c.chr}.join.split("\0")[0] == "name1")
+assert("data_aref", :must,
+       ptr["name"].collect{|c| c.chr}.join.split("\0")[0] == "name1") unless (Fixnum === :-)
+
+GC.start
diff --git a/ext/dl/type.rb b/ext/dl/type.rb
new file mode 100644
index 0000000000..804420c395
--- /dev/null
+++ b/ext/dl/type.rb
@@ -0,0 +1,115 @@
+# example:
+#  DLTYPE[INT][:rb2c]["arg0"] => "NUM2INT(arg0)"
+#  DLTYPE[DOUBLE][:c2rb]["r"] => "rb_float_new(r)"
+
+DLTYPE = {
+  VOID  = 0x00 => {
+    :name => 'VOID',
+    :rb2c => nil,
+    :c2rb => nil,
+    :ctype => "void",
+    :stmem => "v",
+    :sym => true,
+    :cb => true,
+  },
+  CHAR  = 0x01 => {
+    :name => 'CHAR',
+    :rb2c => proc{|x| "NUM2CHR(#{x})"},
+    :c2rb => proc{|x| "CHR2FIX(#{x})"},
+    :ctype => "char",
+    :stmem => "c",
+    :sym => false,
+    :cb => false,
+  },
+  SHORT = 0x02 => {
+    :name => 'SHORT',
+    :rb2c => proc{|x| "FIX2INT(#{x})"},
+    :c2rb => proc{|x| "INT2FIX(#{x})"},
+    :ctype => "short",
+    :stmem => "h",
+    :sym => false,
+    :cb => false,
+  },
+  INT   = 0x03 => {
+    :name => 'INT',
+    :rb2c => proc{|x| "NUM2INT(#{x})"},
+    :c2rb => proc{|x| "INT2NUM(#{x})"},
+    :ctype => "int",
+    :stmem => "i",
+    :sym => true,
+    :cb => false,
+  },
+  LONG  = 0x04 => {
+    :name => 'LONG',
+    :rb2c => proc{|x| "NUM2INT(#{x})"},
+    :c2rb => proc{|x| "INT2NUM(#{x})"},
+    :ctype => "long",
+    :stmem => "l",
+    :sym => true,
+    :cb => true,
+  },
+  FLOAT = 0x05 => {
+    :name => 'FLOAT',
+    :rb2c => proc{|x| "(float)(RFLOAT(#{x})->value)"},
+    :c2rb => proc{|x| "rb_float_new((double)#{x})"},
+    :ctype => "float",
+    :stmem => "f",
+    :sym => false,
+    :cb => false,
+  },
+  DOUBLE = 0x06 => {
+    :name => 'DOUBLE',
+    :rb2c => proc{|x| "RFLOAT(#{x})->value"},
+    :c2rb => proc{|x| "rb_float_new(#{x})"},
+    :ctype => "double",
+    :stmem => "d",
+    :sym => true,
+    :cb => true,
+  },
+  VOIDP = 0x07 => {
+    :name => 'VOIDP',
+    :rb2c => proc{|x| "rb_dlptr2cptr(#{x})"},
+    :c2rb => proc{|x| "rb_dlptr_new(#{x},sizeof(void*),0)"},
+    :ctype => "void *",
+    :stmem => "p",
+    :sym => true,
+    :cb => true,
+  },
+}
+
+def tpush(t, x)
+  (t << 3)|x
+end
+
+def tget(t, i)
+  (t & (0x07 << (i * 3))) >> (i * 3)
+end
+
+def types2num(types)
+  res = 0x00
+  r = types.reverse
+  r.each{|t|
+    res = tpush(res,t)
+  }
+  res
+end
+
+def num2types(num)
+  ts = []
+  i  = 0
+  t = tget(num,i)
+  while( (t != VOID && i > 0) || (i == 0) )
+    ts.push(DLTYPE[t][:ctype])
+    i += 1
+    t = tget(num,i)
+  end
+  ts
+end
+
+def types2ctypes(types)
+  res = []
+  types.each{|t|
+    res.push(DLTYPE[t][:ctype])
+  }
+  res
+end