Use fiddle (win32/importer) instead of Win32API

- ext/win32/lib/win32/sspi.rb: Use fiddle (win32/importer) instead of Win32API

ext/win32/lib/win32/sspi.rb

@@ -11,7 +11,7 @@
 # Ruby Distribution License or GNU General Public License.
 #
 
-require 'Win32API'
+require 'win32/importer'
 
 # Implements bindings to Win32 SSPI functions, focused on authentication to a proxy server over HTTP.
 module Win32
@@ -36,14 +36,21 @@ module Win32
 
     # Win32 API Functions. Uses Win32API to bind methods to constants contained in class.
     module API
-			# Can be called with AcquireCredentialsHandle.call()
-			AcquireCredentialsHandle = Win32API.new("secur32", "AcquireCredentialsHandle", 'ppLpppppp', 'L')
-			# Can be called with InitializeSecurityContext.call()
-			InitializeSecurityContext = Win32API.new("secur32", "InitializeSecurityContext", 'pppLLLpLpppp', 'L')
+      extend Importer
+      dlload "secur32.dll"
+      [
+        # Can be called with AcquireCredentialsHandleA.call()
+        "unsigned long AcquireCredentialsHandleA(void *, void *, unsigned long, void *, void *, void *, void *, void *, void *)",
+        # Can be called with InitializeSecurityContextA.call()
+        "unsigned long InitializeSecurityContextA(void *, void *, void *, unsigned long, unsigned long, unsigned long, void *, unsigned long, void *, void *, void *, void *)",
         # Can be called with DeleteSecurityContext.call()
-			DeleteSecurityContext = Win32API.new("secur32", "DeleteSecurityContext", 'P', 'L')
+        "unsigned long DeleteSecurityContext(void *)",
         # Can be called with FreeCredentialsHandle.call()
-			FreeCredentialsHandle = Win32API.new("secur32", "FreeCredentialsHandle", 'P', 'L')
+        "unsigned long FreeCredentialsHandle(void *)"
+      ].each do |fn|
+        cfunc = extern fn, :stdcall
+        const_set cfunc.name.intern, cfunc
+      end
     end
 
     # SecHandle struct
@@ -254,7 +261,7 @@ module Win32
         @context = CtxtHandle.new
         @contextAttributes = "\0" * 4
 
-				result = SSPIResult.new(API::InitializeSecurityContext.call(@credentials.to_p, nil, nil,
+        result = SSPIResult.new(API::InitializeSecurityContextA.call(@credentials.to_p, nil, nil,
           REQUEST_FLAGS,0, SECURITY_NETWORK_DREP, nil, 0, @context.to_p, outputBuffer.to_p, @contextAttributes, TimeStamp.new.to_p))
 
         if result.ok? then
@@ -317,7 +324,7 @@ module Win32
         @credentials = CredHandle.new
         ts = TimeStamp.new
         @identity = Identity.new @user, @domain
-				result = SSPIResult.new(API::AcquireCredentialsHandle.call(nil, "Negotiate", SECPKG_CRED_OUTBOUND, nil, @identity.to_p,
+        result = SSPIResult.new(API::AcquireCredentialsHandleA.call(nil, "Negotiate", SECPKG_CRED_OUTBOUND, nil, @identity.to_p,
           nil, nil, @credentials.to_p, ts.to_p))
         raise "Error acquire credentials: #{result}" unless result.ok?
       end