CloverBootloader/BaseTools/Source/Python/Common/Edk2/Capsule/FmpPayloadHeader.py

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## @file
# Module that encodes and decodes a FMP_PAYLOAD_HEADER with a payload.
# The FMP_PAYLOAD_HEADER is processed by the FmpPayloadHeaderLib in the
# FmpDevicePkg.
#
# Copyright (c) 2018, Intel Corporation. All rights reserved.<BR>
# SPDX-License-Identifier: BSD-2-Clause-Patent
#
'''
FmpPayloadHeader
'''
import struct
def _SIGNATURE_32 (A, B, C, D):
return struct.unpack ('=I',bytearray (A + B + C + D, 'ascii'))[0]
def _SIGNATURE_32_TO_STRING (Signature):
return struct.pack ("<I", Signature).decode ()
class FmpPayloadHeaderClass (object):
#
# typedef struct {
# UINT32 Signature;
# UINT32 HeaderSize;
# UINT32 FwVersion;
# UINT32 LowestSupportedVersion;
# } FMP_PAYLOAD_HEADER;
#
# #define FMP_PAYLOAD_HEADER_SIGNATURE SIGNATURE_32 ('M', 'S', 'S', '1')
#
_StructFormat = '<IIII'
_StructSize = struct.calcsize (_StructFormat)
_FMP_PAYLOAD_HEADER_SIGNATURE = _SIGNATURE_32 ('M', 'S', 'S', '1')
def __init__ (self):
self._Valid = False
self.Signature = self._FMP_PAYLOAD_HEADER_SIGNATURE
self.HeaderSize = self._StructSize
self.FwVersion = 0x00000000
self.LowestSupportedVersion = 0x00000000
self.Payload = b''
def Encode (self):
FmpPayloadHeader = struct.pack (
self._StructFormat,
self.Signature,
self.HeaderSize,
self.FwVersion,
self.LowestSupportedVersion
)
self._Valid = True
return FmpPayloadHeader + self.Payload
def Decode (self, Buffer):
if len (Buffer) < self._StructSize:
raise ValueError
(Signature, HeaderSize, FwVersion, LowestSupportedVersion) = \
struct.unpack (
self._StructFormat,
Buffer[0:self._StructSize]
)
if Signature != self._FMP_PAYLOAD_HEADER_SIGNATURE:
raise ValueError
if HeaderSize < self._StructSize:
raise ValueError
self.Signature = Signature
self.HeaderSize = HeaderSize
self.FwVersion = FwVersion
self.LowestSupportedVersion = LowestSupportedVersion
self.Payload = Buffer[self.HeaderSize:]
self._Valid = True
return self.Payload
def DumpInfo (self):
if not self._Valid:
raise ValueError
print ('FMP_PAYLOAD_HEADER.Signature = {Signature:08X} ({SignatureString})'.format (Signature = self.Signature, SignatureString = _SIGNATURE_32_TO_STRING (self.Signature)))
print ('FMP_PAYLOAD_HEADER.HeaderSize = {HeaderSize:08X}'.format (HeaderSize = self.HeaderSize))
print ('FMP_PAYLOAD_HEADER.FwVersion = {FwVersion:08X}'.format (FwVersion = self.FwVersion))
print ('FMP_PAYLOAD_HEADER.LowestSupportedVersion = {LowestSupportedVersion:08X}'.format (LowestSupportedVersion = self.LowestSupportedVersion))
print ('sizeof (Payload) = {Size:08X}'.format (Size = len (self.Payload)))