class Facter::Util::Windows::FFI
Constants
- ERROR_SUCCESS
- NULL_HANDLE
- WIN32_FALSE
standard Win32 error codes
Public Class Methods
read_arbitrary_wide_string_up_to(ffi_pointer, max_char_length = 512, null_terminator = :single_null)
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@param max_char_length [Integer] Maximum number of wide chars to return (typically excluding NULLs), not bytes @param null_terminator [Symbol] Number of number of null wchar characters, not bytes, that determine the end of the string
null_terminator = :single_null, then the terminating sequence is two bytes of zero. This is UNIT16 = 0 null_terminator = :double_null, then the terminating sequence is four bytes of zero. This is UNIT32 = 0
# File lib/facter/util/windows/api_types.rb, line 35 def self.read_arbitrary_wide_string_up_to(ffi_pointer, max_char_length = 512, null_terminator = :single_null) if null_terminator != :single_null && null_terminator != :double_null raise _("Unable to read wide strings with %{null_terminator} terminal nulls") % { null_terminator: null_terminator } end terminator_width = null_terminator == :single_null ? 1 : 2 reader_method = null_terminator == :single_null ? :get_uint16 : :get_uint32 # Look for a null terminating characters; if found, read up to that null (exclusive) (0...max_char_length - terminator_width).each do |i| return read_wide_string(ffi_pointer, i) if ffi_pointer.send(reader_method, (i * 2)) == 0 end # String is longer than the max; read just to the max read_wide_string(ffi_pointer, max_char_length) end
read_dword(ffi_pointer)
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# File lib/facter/util/windows/api_types.rb, line 17 def self.read_dword(ffi_pointer) ffi_pointer.read_uint32 end
read_handle(ffi_pointer)
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# File lib/facter/util/windows/api_types.rb, line 21 def self.read_handle(ffi_pointer) ffi_pointer.type_size == 4 ? ffi_pointer.read_uint32 : ffi_pointer.read_uint64 end
read_wide_string(ffi_pointer, char_length, dst_encoding = Encoding::UTF_8)
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# File lib/facter/util/windows/api_types.rb, line 25 def self.read_wide_string(ffi_pointer, char_length, dst_encoding = Encoding::UTF_8) # char_length is number of wide chars (typically excluding NULLs), *not* bytes str = ffi_pointer.get_bytes(0, char_length * 2).force_encoding('UTF-16LE') str.encode(dst_encoding) end
read_win32_bool(ffi_pointer)
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# File lib/facter/util/windows/api_types.rb, line 11 def self.read_win32_bool(ffi_pointer) # BOOL is always a 32-bit integer in Win32 # some Win32 APIs return 1 for true, while others are non-0 ffi_pointer.read_int32 != WIN32_FALSE end
read_win32_local_pointer(ffi_pointer) { |ptr| ... }
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# File lib/facter/util/windows/api_types.rb, line 52 def self.read_win32_local_pointer(ffi_pointer, &block) ptr = nil begin ptr = ffi_pointer.read_pointer yield ptr ensure if ptr && ! ptr.null? if WIN32.LocalFree(ptr.address) != NULL_HANDLE Puppet.debug "LocalFree memory leak" end end end # ptr has already had LocalFree called, so nothing to return nil end