I'm trying to use AutoPointer or ManagedStruct to free some memory for
a gss_buffer_desc struct in the GSSAPI.  It seems I can free the
object manually, but when wrapped in an AutoPointer or ManagedStruct I
get a SegFault.

This is working, but I need to be able to free the memory in an
automatic fashion.

# --------- Example One ---------
class GssBufferDesc < FFI::Struct
  layout  :length => :size_t,
          :value  => :pointer # pointer of :void
end

.... misc code

output_token = LibGSSAPI::GssBufferDesc.new
output_token[:length] = 0
output_token[:value] = nil
maj_stat = LibGSSAPI.gss_init_sec_context(...,
output_token.pointer,...)

... do work

maj_stat = LibGSSAPI.gss_release_buffer(min_stat,
output_token.pointer)
# gss_release_buffer exists with success:w


# --------- Example Two ---------  This example gets a SegFault

class GssBufferT < FFI::AutoPointer
  def self.release(buffer_ptr)
    puts "Releasing gss_buffer_t at #{buffer_ptr.address}" if $DEBUG
    min_stat = FFI::MemoryPointer.new :uint32
    maj_stat = LibGSSAPI.gss_release_buffer(min_stat, buffer_ptr)
  end
end

.... misc code

output_token = FFI::MemoryPointer.new :pointer
maj_stat = LibGSSAPI.gss_init_sec_context(..., output_token, ...)
LibGSSAPI::GssBufferT.new(output_token.get_pointer(0))

# on exit the release method in GssBufferT causes a segfault and if I
wrap it in a ManagedStruct the same thing happens.  Does anyone have
any ideas for me?

Cheers,

Dan Wanek