Use ffi for GetVolumeNameForVolumeMountPoint

3 files changed, 18 insertions, 5 deletions

diff --git a/lib/chef/util/windows/volume.rb b/lib/chef/util/windows/volume.rb
index e28a5091ac..e29179277c 100644
--- a/lib/chef/util/windows/volume.rb
+++ b/lib/chef/util/windows/volume.rb
@@ -35,11 +35,10 @@ class Chef::Util::Windows::Volume < Chef::Util::Windows
   end
 
   def device
-    buffer = 0.chr * 256
-    if GetVolumeNameForVolumeMountPoint(@name, buffer, buffer.size)
-      return buffer[0,buffer.size].unpack("Z*")[0]
-    else
-      raise ArgumentError, get_last_error
+    begin
+      Chef::ReservedNames::Win32::File.get_volume_name_for_volume_mount_point(@name)
+    rescue Chef::Exceptions::Win32APIError => e
+      raise ArgumentError, e
     end
   end
 
diff --git a/lib/chef/win32/api/file.rb b/lib/chef/win32/api/file.rb
index c48e992882..728a6c14df 100644
--- a/lib/chef/win32/api/file.rb
+++ b/lib/chef/win32/api/file.rb
@@ -462,6 +462,13 @@ BOOL WINAPI DeviceIoControl(
 #);
         safe_attach_function :SetVolumeMountPointW, [:LPCTSTR, :LPCTSTR], :BOOL
 
+#BOOL WINAPI GetVolumeNameForVolumeMountPoint(
+  #_In_  LPCTSTR lpszVolumeMountPoint,
+  #_Out_ LPTSTR  lpszVolumeName,
+  #_In_  DWORD   cchBufferLength
+#);
+        safe_attach_function :GetVolumeNameForVolumeMountPointW, [:LPCTSTR, :LPTSTR, :DWORD], :BOOL
+
         ###############################################
         # Helpers
         ###############################################
diff --git a/lib/chef/win32/file.rb b/lib/chef/win32/file.rb
index f62f9333f5..57347643fc 100644
--- a/lib/chef/win32/file.rb
+++ b/lib/chef/win32/file.rb
@@ -192,6 +192,13 @@ class Chef
         end
       end
 
+      def self.get_volume_name_for_volume_mount_point(mount_point)
+        buffer = FFI::MemoryPointer.new(2, 128)
+        unless GetVolumeNameForVolumeMountPointW(wstring(mount_point), buffer, buffer.size/buffer.type_size)
+          Chef::ReservedNames::Win32::Error.raise!
+        end
+        buffer.read_wstring
+      end
 
       # ::File compat
       class << self