Coverage for /pythoncovmergedfiles/medio/medio/usr/local/lib/python3.8/site-packages/flatbuffers/util.py: 44%

1# Copyright 2017 Google Inc. All rights reserved. 

2# 

3# Licensed under the Apache License, Version 2.0 (the "License"); 

4# you may not use this file except in compliance with the License. 

5# You may obtain a copy of the License at 

6# 

7# http://www.apache.org/licenses/LICENSE-2.0 

8# 

9# Unless required by applicable law or agreed to in writing, software 

10# distributed under the License is distributed on an "AS IS" BASIS, 

11# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 

12# See the License for the specific language governing permissions and 

13# limitations under the License. 

14 

15from . import encode 

16from . import number_types 

17from . import packer 

18 

19def GetSizePrefix(buf, offset): 

20 """Extract the size prefix from a buffer.""" 

21 return encode.Get(packer.int32, buf, offset) 

22 

23def GetBufferIdentifier(buf, offset, size_prefixed=False): 

24 """Extract the file_identifier from a buffer""" 

25 if size_prefixed: 

26 # increase offset by size of UOffsetTFlags 

27 offset += number_types.UOffsetTFlags.bytewidth 

28 # increase offset by size of root table pointer 

29 offset += number_types.UOffsetTFlags.bytewidth 

30 # end of FILE_IDENTIFIER 

31 end = offset + encode.FILE_IDENTIFIER_LENGTH 

32 return buf[offset:end] 

33 

34def BufferHasIdentifier(buf, offset, file_identifier, size_prefixed=False): 

35 got = GetBufferIdentifier(buf, offset, size_prefixed=size_prefixed) 

36 return got == file_identifier 

37 

38def RemoveSizePrefix(buf, offset): 

39 """ 

40 Create a slice of a size-prefixed buffer that has 

41 its position advanced just past the size prefix. 

42 """ 

43 return buf, offset + number_types.Int32Flags.bytewidth