#!/usr/bin/python3-dbg
# -*- coding: utf-8 -*-
import locale
from chrysacase import ChrysalideTestCase
from pychrysalide.analysis.contents import MemoryContent
from pychrysalide.plugins.kaitai.parsers import KaitaiStruct
class TestKaitaiStruct(ChrysalideTestCase):
"""TestCase for the KaitaiStruct parsing."""
@classmethod
def setUpClass(cls):
super(TestKaitaiStruct, cls).setUpClass()
cls.log('Setting locale suitable for floats...')
cls._old_locale = locale.getlocale(locale.LC_NUMERIC)
locale.setlocale(locale.LC_NUMERIC, 'C')
@classmethod
def tearDownClass(cls):
super(TestKaitaiStruct, cls).tearDownClass()
cls.log('Reverting locale...')
locale.setlocale(locale.LC_NUMERIC, cls._old_locale)
#################################
### 4. Kaitai Struct language
#################################
def testKaitaiFixedLength(self):
"""Load fixed-size structures."""
# Cf. 4.1. Fixed-size structures
definitions = '''
meta:
id: mydesc
title: My Long Title
endian: be
seq:
- id: field0
type: u4
'''
kstruct = KaitaiStruct(definitions)
self.assertEqual(kstruct.meta.id, 'mydesc')
self.assertEqual(kstruct.meta.title, 'My Long Title')
content = MemoryContent(b'\x01\x02\x03\x04')
parsed = kstruct.parse(content)
self.assertEqual(parsed.field0.range.length, 4)
self.assertEqual(parsed.field0.value, 0x01020304)
definitions = '''
meta:
endian: le
seq:
- id: field0
type: u4
- id: field1
type: u4be
'''
kstruct = KaitaiStruct(definitions)
self.assertIsNone(kstruct.meta.id)
self.assertIsNone(kstruct.meta.title)
content = MemoryContent(b'\x01\x02\x03\x04\x01\x02\x03\x04')
parsed = kstruct.parse(content)
self.assertEqual(parsed.field0.range.length, 4)
self.assertEqual(parsed.field0.value, 0x04030201)
self.assertEqual(parsed.field1.range.length, 4)
self.assertEqual(parsed.field1.value, 0x01020304)
definitions = '''
seq:
- id: field0
type: u1
- id: field1
size: 2
- id: field2
size: field0 + 1
'''
kstruct = KaitaiStruct(definitions)
content = MemoryContent(b'\x01\x02\x03\x04\x05')
parsed = kstruct.parse(content)
self.assertEqual(parsed.field0.range.length, 1)
self.assertEqual(parsed.field0.value, 0x01)
self.assertEqual(parsed.field1.range.length, 2)
self.assertEqual(parsed.field1.truncated_bytes, b'\x02\x03')
self.assertEqual(parsed.field2.range.length, 2)
self.assertEqual(parsed.field2.truncated_bytes, b'\x04\x05')
def testDocstrings(self):
"""Handle Kaitai documentation."""
# Cf. 4.2. Docstrings
definitions = '''
seq:
- id: rating
type: s4
doc: Rating, can be negative
'''
kstruct = KaitaiStruct(definitions)
content = MemoryContent(b'\x01\x02\x02\x04')
parsed = kstruct.parse(content)
self.assertEqual(parsed.rating.creator.doc, 'Rating, can be negative')
def testKaitaiContents(self):
"""Read various forms of fixed content."""
# Cf. 4.3. Checking for "magic" signatures
definitions = '''
seq:
- id: field0
contents: [ 0, 0x10, '22', "50 ]
'''
# ValueError: Unable to create Kaitai structure.
with self.assertRaisesRegex(ValueError, "Unable to create Kaitai structure"):
kstruct = KaitaiStruct(definitions)
self.assertIsNotNone(kstruct)
definitions = '''
seq:
- id: field0
contents: [ 0x41, 66, 'CD' ]
'''
kstruct = KaitaiStruct(definitions)
content = MemoryContent(b'ABCD')
parsed = kstruct.parse(content)
self.assertEqual(parsed.field0.range.length, 4)
self.assertEqual(parsed.field0.value, b'ABCD')
definitions = '''
seq:
- id: field0
contents: ABCD
'''
kstruct = KaitaiStruct(definitions)
content = MemoryContent(b'ABCD')
parsed = kstruct.parse(content)
self.assertEqual(parsed.field0.range.length, 4)
definitions = '''
seq:
- id: field0
contents: "ABCD"
'''
kstruct = KaitaiStruct(definitions)
content = MemoryContent(b'ABCD')
parsed = kstruct.parse(content)
self.assertEqual(parsed.field0.range.length, 4)
definitions = '''
seq:
- id: field0
contents:
- 0x41
- "B"
- CD
'''
kstruct = KaitaiStruct(definitions)
content = MemoryContent(b'ABCD')
parsed = kstruct.parse(content)
self.assertEqual(parsed.field0.range.length, 4)
def testVariableLengthStructures(self):
"""Parse variable-length structures."""
# Cf. 4.4. Variable-length structures
definitions = '''
seq:
- id: my_len
type: u1
- id: my_str
type: str
size: my_len
'''
kstruct = KaitaiStruct(definitions)
content = MemoryContent(b'\x03ABC')
parsed = kstruct.parse(content)
self.assertEqual(parsed.my_len.value, 3)
self.assertEqual(parsed.my_str.value, b'ABC')
definitions = '''
seq:
- id: my_len
type: u1
- id: my_str
type: str
size: my_len * 2
'''
kstruct = KaitaiStruct(definitions)
content = MemoryContent(b'\x03ABCDEF')
parsed = kstruct.parse(content)
self.assertEqual(parsed.my_len.value, 3)
self.assertEqual(parsed.my_str.value, b'ABCDEF')
definitions = '''
seq:
- id: field0
size-eos: true
'''
kstruct = KaitaiStruct(definitions)
content = MemoryContent(b'\x01\x02\x02\x03')
parsed = kstruct.parse(content)
self.assertEqual(content, parsed.content)
self.assertEqual(parsed.range.addr.phys, 0)
self.assertEqual(parsed.range.length, len(content.data))
def testDelimitedStructures(self):
"""Parse delimited structures."""
# Cf. 4.5. Delimited structures
definitions = '''
seq:
- id: my_string
type: str
terminator: 0
'''
kstruct = KaitaiStruct(definitions)
content = MemoryContent(b'ABC\x00DEF')
parsed = kstruct.parse(content)
self.assertEqual(parsed.my_string.value, b'ABC')
definitions = '''
seq:
- id: my_string
type: strz
'''
kstruct = KaitaiStruct(definitions)
content = MemoryContent(b'ABC\x00DEF')
parsed = kstruct.parse(content)
self.assertEqual(parsed.my_string.value, b'ABC')
definitions = '''
seq:
- id: name
type: str
size: 8
terminator: 0
- id: guard
size: 1
'''
kstruct = KaitaiStruct(definitions)
content = MemoryContent(b'ABC\x00\x00\x00\x00\x00x\x00')
parsed = kstruct.parse(content)
self.assertEqual(parsed.name.value, b'ABC')
self.assertEqual(parsed.guard.value, b'x')
def __passed__testEnums(self):
"""Parse delimited structures."""
# Cf. 4.6. Enums (named integer constants)
pass
def testSubTypes(self):
"""Includes subtypes definitions."""
# Cf. 4.7. Substructures (subtypes)
definitions = '''
seq:
- id: field0
type: custom_type
- id: field1
type: custom_type
- id: field2
type: custom_type
types:
custom_type:
seq:
- id: len
type: u1
- id: value
size: len
'''
kstruct = KaitaiStruct(definitions)
content = MemoryContent(b'\x01\xaa\x02\xbb\xbb\x03\xcc\xcc\xcc')
parsed = kstruct.parse(content)
self.assertEqual(parsed.field0.len.value, 1)
self.assertEqual(parsed.field0.value.truncated_bytes, b'\xaa')
self.assertEqual(parsed.field1.len.value, 2)
self.assertEqual(parsed.field1.value.truncated_bytes, b'\xbb\xbb')
self.assertEqual(parsed.field2.len.value, 3)
self.assertEqual(parsed.field2.value.truncated_bytes, b'\xcc\xcc\xcc')
def testOtherAttributesAccess(self):
"""Access attributes in other types."""
# Cf. 4.8. Accessing attributes in other types
definitions = '''
seq:
- id: header
type: main_header
- id: body
size: header.body_len
types:
main_header:
seq:
- id: magic
contents: FMT
- id: body_len
type: u1
'''
kstruct = KaitaiStruct(definitions)
content = MemoryContent(b'FMT\x04\xaa\xbb\xcc\xdd')
parsed = kstruct.parse(content)
self.assertEqual(parsed.header.magic.raw_bytes, b'FMT')
self.assertEqual(parsed.header.magic.range.length, 3)
self.assertEqual(parsed.header.body_len.value, 4)
self.assertEqual(parsed.body.raw_bytes, b'\xaa\xbb\xcc\xdd')
self.assertEqual(parsed.body.range.length, 4)
def testConditionals(self):
"""Read Kaitai values according to previous loaded values."""
# Cf. 4.9. Conditionals
definitions = '''
seq:
- id: field1
type: u1
- id: field2
type: u1
- id: field3
type: u1
if: field1 + field2 > 10
- id: field4
type: u1
'''
kstruct = KaitaiStruct(definitions)
content = MemoryContent(b'\x01\x02\x03\x04')
parsed = kstruct.parse(content)
self.assertEqual(parsed.field1.value, 0x01)
self.assertEqual(parsed.field2.value, 0x02)
self.assertFalse(hasattr(parsed, 'field3'))
self.assertEqual(parsed.field4.value, 0x03)
definitions = '''
seq:
- id: field1
type: u1
- id: field2
type: u1
- id: field3
type: u1
if: field1 + field2 > 1
- id: field4
type: u1
'''
kstruct = KaitaiStruct(definitions)
content = MemoryContent(b'\x01\x02\x03\x04')
parsed = kstruct.parse(content)
self.assertEqual(parsed.field1.value, 0x01)
self.assertEqual(parsed.field2.value, 0x02)
self.assertTrue(hasattr(parsed, 'field3'))
self.assertEqual(parsed.field4.value, 0x04)
definitions = '''
seq:
- id: field1
type: u1
- id: field2
type: u1
- id: field3
type: u1
if: field1 + field2 == threshold::three
- id: field4
type: u1
enums:
threshold:
1: one
2: two
3: three
'''
kstruct = KaitaiStruct(definitions)
content = MemoryContent(b'\x01\x02\x03\x04')
parsed = kstruct.parse(content)
self.assertEqual(parsed.field1.value, 0x01)
self.assertEqual(parsed.field2.value, 0x02)
self.assertTrue(hasattr(parsed, 'field3'))
self.assertEqual(parsed.field4.value, 0x04)
def testRepeatedReadUntilEOS(self):
"""Read items until the end of the stream."""
# Cf. 4.10.1. Repeat until end of stream
definitions = '''
seq:
- id: field0
type: u2be
repeat: eos
'''
kstruct = KaitaiStruct(definitions)
content = MemoryContent(b'\x01\x00\x02\x00\x03\x00\x04\x00')
parsed = kstruct.parse(content)
self.assertEqual(len(parsed.field0), len(content.data) / 2)
for i in range(4):
self.assertEqual(parsed.field0[i].value, (i + 1) << 8)
def testRepeatedReadAccordingToCounter(self):
"""Repeat read of items for a nomber of times."""
# Cf. 4.10.2. Repeat for a number of times
definitions = '''
seq:
- id: field0
type: u1
- id: field1
type: u1
repeat: expr
repeat-expr: 1
'''
kstruct = KaitaiStruct(definitions)
content = MemoryContent(b'\x01\x01')
parsed = kstruct.parse(content)
self.assertEqual(parsed.field0.value, 0x01)
self.assertEqual(len(parsed.field1), 1)
for i in range(1):
self.assertEqual(parsed.field1[i].value, i + 1)
definitions = '''
seq:
- id: field0
type: u1
- id: field1
type: u1
- id: field2
type: u2
repeat: expr
repeat-expr: field0 + field1
'''
kstruct = KaitaiStruct(definitions)
content = MemoryContent(b'\x01\x02\x01\x00\x02\x00\x03\x00')
parsed = kstruct.parse(content)
self.assertEqual(parsed.field0.value, 0x01)
self.assertEqual(parsed.field1.value, 0x02)
self.assertEqual(len(parsed.field2), 3)
for i in range(3):
self.assertEqual(parsed.field2[i].value, i + 1)
def testRepeatUntilConditionIsMet(self):
"""Repeat until condition is met."""
# Cf. 4.10.3. Repeat until condition is met
definitions = '''
seq:
- id: numbers
type: u1
repeat: until
repeat-until: _ == 0xff
- id: extra
type: u1
'''
kstruct = KaitaiStruct(definitions)
content = MemoryContent(b'\x01\x02\xff\xcc')
parsed = kstruct.parse(content)
self.assertEqual(len(parsed.numbers), 3)
for i in range(2):
self.assertEqual(parsed.numbers[i].value, i + 1)
self.assertEqual(parsed.numbers[2].value, 0xff)
self.assertEqual(parsed.extra.value, 0xcc)
definitions = '''
seq:
- id: records
type: buffer_with_len
repeat: until
repeat-until: _.len == 0
types:
buffer_with_len:
seq:
- id: len
type: u1
- id: value
size: len
'''
kstruct = KaitaiStruct(definitions)
content = MemoryContent(b'\x02\xaa\xaa\x01\xbb\x00')
parsed = kstruct.parse(content)
self.assertEqual(parsed.records[0].len.value, 2)
self.assertEqual(parsed.records[0].value.raw_bytes, b'\xaa\xaa')
self.assertEqual(parsed.records[1].len.value, 1)
self.assertEqual(parsed.records[1].value.raw_bytes, b'\xbb')
self.assertEqual(parsed.records[2].len.value, 0)
self.assertEqual(parsed.records[2].value.raw_bytes, b'')
def testParseTLVImplementation(self):
"""Parse a typical TLV implementation."""
# Cf. 4.11. Typical TLV implementation (switching types on an expression)
definitions = '''
seq:
- id: record
type: rec_def
repeat: eos
types:
rec_def:
seq:
- id: rec_type
type: u1
- id: len
type: u1
- id: body
size: len
type:
switch-on: rec_type
cases:
1: rec_type_1
2: rec_type_2
rec_type_1:
seq:
- id: field1
type: u1
rec_type_2:
seq:
- id: field2
type: u2
'''
kstruct = KaitaiStruct(definitions)
content = MemoryContent(b'\x01\x01\xaa\x02\x02\xcc\xbb')
parsed = kstruct.parse(content)
self.assertEqual(len(parsed.record), 2)
self.assertEqual(parsed.record[0].rec_type.value, 1)
self.assertEqual(parsed.record[0].len.value, 1)
self.assertEqual(parsed.record[0].body.field1.value, 0xaa)
self.assertEqual(parsed.record[1].rec_type.value, 2)
self.assertEqual(parsed.record[1].len.value, 2)
self.assertEqual(parsed.record[1].body.field2.value, 0xbbcc)
def testInstanceWithDataBeyondTheSequence(self):
"""Build instances with data beyond the sequence."""
# Cf. 4.12. Instances: data beyond the sequence
definitions = '''
instances:
some_integer:
pos: 0x4
type: u1
'''
kstruct = KaitaiStruct(definitions)
content = MemoryContent(b'\x01\x02\x03\x04\x05\x06\x07\x08')
parsed = kstruct.parse(content)
self.assertEqual(parsed.some_integer.value, 5)
definitions = '''
seq:
- id: file_offset
type: u1
- id: file_size
type: u1
instances:
body:
pos: file_offset
size: file_size
'''
kstruct = KaitaiStruct(definitions)
content = MemoryContent(b'\x04\x02\x90\x90ABCD')
parsed = kstruct.parse(content)
self.assertEqual(parsed.file_offset.value, 4)
self.assertEqual(parsed.file_size.value, 2)
self.assertEqual(parsed.body.value, b'AB')
def testValueInstances(self):
"""Build value instances"""
# Cf. 4.13. Value instances
definitions = '''
seq:
- id: length
type: u1
- id: extra
type: u1
instances:
length_extended:
value: length * 3 + extra
'''
kstruct = KaitaiStruct(definitions)
content = MemoryContent(b'\x01\x02\x03\x04')
parsed = kstruct.parse(content)
self.assertEqual(parsed.length.value, 1)
self.assertEqual(parsed.extra.value, 2)
self.assertEqual(parsed.length_extended.value, 5)
def testBitSizedIntegers(self):
"""Read bit-sized integers."""
# Cf. 4.14. Bit-sized integers
definitions = '''
seq:
- id: packed_1
type: u1
instances:
version:
value: (packed_1 & 0b11110000) >> 4
len_header:
value: packed_1 & 0b00001111
'''
kstruct = KaitaiStruct(definitions)
content = MemoryContent(b'\x9a')
parsed = kstruct.parse(content)
self.assertEqual(parsed.packed_1.value, 0x9a)
self.assertEqual(parsed.version.value, 0x9)
self.assertEqual(parsed.len_header.value, 0xa)
def __passed__testBitSizedIntegersBigEndian(self):
"""Read bit-sized integers."""
# Cf. 4.14.1. Big-endian order
pass
def __passed__testBitSizedIntegersLittleEndian(self):
"""Read bit-sized integers."""
# Cf. 4.14.2. Little-endian order
pass
def __passed__testBitSizedIntegersSpecifiedEndianness(self):
"""Read bit-sized integers with specified bit endianness."""
# Cf. 4.14.3. Specifying bit endianness
pass
#################################
### 5. Streams and substreams
#################################
def testTotalSizeLimit(self):
"""Limit total size of structure."""
# Cf. 5.1. Limiting total size of structure
definitions = '''
seq:
- id: body_len
type: u1
- id: random
size: 2
- id: comment
size: body_len - 2
- id: extra
type: u1
'''
kstruct = KaitaiStruct(definitions)
content = MemoryContent(b'\x05\x01\x02---\xbb')
parsed = kstruct.parse(content)
self.assertEqual(parsed.body_len.value, 0x05)
self.assertEqual(parsed.random.raw_bytes, b'\x01\x02')
self.assertEqual(parsed.comment.raw_bytes, b'---')
self.assertEqual(parsed.extra.raw_bytes, b'\xbb')
definitions = '''
seq:
- id: body_len
type: u1
- id: body
type: record_body
size: body_len
- id: extra
type: u1
types:
record_body:
seq:
- id: random
size: 2
- id: comment
size-eos: true
'''
kstruct = KaitaiStruct(definitions)
content = MemoryContent(b'\x05\x01\x02---\xbb')
parsed = kstruct.parse(content)
self.assertEqual(parsed.body_len.value, 0x05)
self.assertEqual(parsed.body.random.raw_bytes, b'\x01\x02')
self.assertEqual(parsed.body.comment.raw_bytes, b'---')
self.assertEqual(parsed.extra.raw_bytes, b'\xbb')
def testRepeatSizeLimit(self):
"""Repeating until total size reaches limit."""
# Cf. 5.2. Repeating until total size reaches limit
content = MemoryContent(b'\x03\x00\x01\x02\xbb')
definitions = '''
seq:
- id: total_len
type: u1
- id: files
type: file_entries
size: total_len
- id: extra
type: u1
types:
file_entries:
seq:
- id: entries
type: entry
repeat: eos
entry:
seq:
- id: index
type: u1
'''
kstruct = KaitaiStruct(definitions)
parsed = kstruct.parse(content)
self.assertEqual(parsed.total_len.value, 3)
self.assertEqual(len(parsed.files.entries), 3)
for i in range(3):
self.assertEqual(parsed.files.entries[i].index.value, i)
self.assertEqual(parsed.extra.value, 0xbb)
def testRelativePositioning(self):
"""Parse with relative positioning."""
# Cf. 5.3. Relative positioning
content = MemoryContent(b'\x00\x01\x02\x03\x04\x05\x06\x07\x08\x09\x0a\x0b\x0c\x0d\0xe\x0f')
definitions = '''
seq:
- id: some_header
size: 4
- id: body
type: block
size: 12
types:
block:
seq:
- id: foo
type: u1
instances:
some_bytes_in_the_middle:
pos: 4
size: 4
'''
kstruct = KaitaiStruct(definitions)
parsed = kstruct.parse(content)
self.assertEqual(parsed.some_header.value, b'\x00\x01\x02\x03')
self.assertEqual(parsed.body.foo.value, 0x04)
self.assertEqual(parsed.body.some_bytes_in_the_middle.value, b'\x08\x09\x0a\x0b')
def testAbsolutePositioning(self):
"""Read from absolute position."""
# Cf. 5.4. Absolute positioning
content = MemoryContent(b'\x06\x03\x00\x00\x00\x00\x01\x02\x03\xbb')
definitions = '''
seq:
- id: items
size: 10
type: entry
repeat: eos
types:
entry:
seq:
- id: ofs_body
type: u1
- id: len_body
type: u1
instances:
body:
io: _root._io
pos: ofs_body
size: len_body
'''
kstruct = KaitaiStruct(definitions)
parsed = kstruct.parse(content)
self.assertEqual(parsed.items[0].ofs_body.value, 6)
self.assertEqual(parsed.items[0].len_body.value, 3)
self.assertEqual(parsed.items[0].body.value, b'\x01\x02\x03')
def testSubstreamChoice(self):
"""Choose a substream."""
# Cf. 5.5. Choosing a substream
content = MemoryContent(b'\xaa\xaa\xaa\xaa\x01\x02\x03\x04\x05\x06\x07\x08\x02\x03')
definitions = '''
seq:
- id: global_header
size: 4
- id: block_one
type: big_container
size: 8
- id: block_two
type: smaller_container
size: 2
types:
big_container:
seq:
- id: some_header
size: 8
smaller_container:
seq:
- id: ofs_in_big
type: u1
- id: len_in_big
type: u1
instances:
something_in_big:
io: _root.block_one._io
pos: ofs_in_big
size: len_in_big
'''
kstruct = KaitaiStruct(definitions)
parsed = kstruct.parse(content)
self.assertEqual(parsed.block_two.ofs_in_big.value, 2)
self.assertEqual(parsed.block_two.len_in_big.value, 3)
self.assertEqual(parsed.block_two.something_in_big.value, b'\x03\x04\x05')
def __passed__testContentPreProcessing(self):
"""Process content before parsing."""
# Cf. 5.6. Processing: dealing with compressed, obfuscated and encrypted data
pass
##############################
### 6. Expression language
##############################
def testBasicDataTypes(self):
"""Handle basic data types."""
# Cf. 6.1. Basic data types
definitions = '''
seq:
- id: field1
type: u1
- id: field2
type: u2
- id: field4
type: u4
- id: field8
type: u8
'''
kstruct = KaitaiStruct(definitions)
content = MemoryContent(b'\x01\x02\x02\x04\x04\x04\x04\x08\x08\x08\x08\x08\x08\x08\x08')
parsed = kstruct.parse(content)
self.assertEqual(parsed.field1.range.length, 1)
self.assertEqual(parsed.field2.range.length, 2)
self.assertEqual(parsed.field4.range.length, 4)
self.assertEqual(parsed.field8.range.length, 8)
definitions = '''
seq:
- id: field1
type: u1
- id: field4
type: u4le
- id: field4bis
type: u4be
'''
kstruct = KaitaiStruct(definitions)
content = MemoryContent(b'\x01\x02\x03\x04\x05\x02\x03\x04\x05')
parsed = kstruct.parse(content)
self.assertEqual(parsed.field1.value, 0x01)
self.assertEqual(parsed.field4.value, 0x05040302)
self.assertEqual(parsed.field4bis.value, 0x02030405)
definitions = '''
instances:
number1:
value: 0xdead_cafe
number2:
value: 0xdead_cafe_dead_cafe
number3:
value: 12_345_678
number4:
value: 0b10100011
number5:
value: 0b1010_0011_1010_0011
'''
content = MemoryContent(b'')
kstruct = KaitaiStruct(definitions)
parsed = kstruct.parse(content)
self.assertEqual(parsed.number1.value, 0xdeadcafe)
self.assertEqual(parsed.number2.value, 0xdeadcafedeadcafe)
self.assertEqual(parsed.number3.value, 12345678)
self.assertEqual(parsed.number4.value, 0b10100011)
self.assertEqual(parsed.number5.value, 0b1010001110100011)
definitions = '''
seq:
- id: op0
type: u1
instances:
result:
value: 0xdeadcafe + op0
result2:
value: 0XdeadCAFE + op0
'''
content = MemoryContent(b'\x00')
kstruct = KaitaiStruct(definitions)
parsed = kstruct.parse(content)
self.assertEqual(parsed.result.value, 0xdeadcafe)
self.assertEqual(parsed.result2.value, 0xdeadcafe)
definitions = '''
instances:
bytes1:
value: []
bytes2:
value: [ ]
bytes3:
value: [ 0x90 ]
bytes4:
value: [foo, 0, A, 0xa, 42]
'''
content = MemoryContent(b'')
kstruct = KaitaiStruct(definitions)
parsed = kstruct.parse(content)
self.assertEqual(parsed.bytes1.value, b'')
self.assertEqual(parsed.bytes2.value, b'')
self.assertEqual(parsed.bytes3.value, b'\x90')
self.assertEqual(parsed.bytes4.value, b'\x66\x6f\x6f\x00\x41\x0a\x2a')
definitions = '''
instances:
escaped:
value: '[ "\\a\\b\\t\\n\\v\\f", "\\0", 0, " \\r\\e\\\"\\123" ]'
'''
content = MemoryContent(b'')
kstruct = KaitaiStruct(definitions)
parsed = kstruct.parse(content)
self.assertEqual(parsed.escaped.value, b'\x07\x08\x09\x0a\x0b\x0c\x00\x00 \x0d\x1b\x22\x53')
definitions_0 = r'''
instances:
escaped:
value: "[ \"\\a\\b\\t\\n\\v\\f\", \"\\0\", 0, \"\\r\\e\\\"'\\123\" ]"
'''
definitions_1 = r'''
instances:
escaped:
value: [ "\\a\\b\\t\\n\\v\\f", "\\0", 0, "\\r\\e\\\"'\\123" ]
'''
definitions_2 = '''
instances:
escaped:
value: [ "\\\\a\\\\b\\\\t\\\\n\\\\v\\\\f", "\\\\0", 0, "\\\\r\\\\e\\\\\\"'\\\\123" ]
'''
for d in [ definitions_0, definitions_1, definitions_2 ]:
content = MemoryContent(b'')
kstruct = KaitaiStruct(d)
parsed = kstruct.parse(content)
self.assertEqual(parsed.escaped.value, b'\x07\x08\x09\x0a\x0b\x0c\x00\x00\x0d\x1b\x22\x27\x53')
def __passed__testUserDefinedTypes(self):
"""Create user-defined types."""
# Cf. 6.2.1. User-defined types
pass
def testArrays(self):
"""Create various arrays."""
# Cf. 6.2.2. Arrays
definitions = '''
instances:
result_0:
value: "[]"
result_1:
value: "[CAFE, 0, BABE]"
result_2:
value: "[CAFE, 0, BABE] == 'CAFE' + [ 0x00 ] + 'BABE'"
result_3:
value: "[CAFE, 0, BABE] == [ 0x43, 0x41, 0x46, 0x45, 0x00, 0x42, 0x41, 0x42, 0x45 ]"
result_4:
value: "[foo, 0, A, 0xa, 42] == [ 0x66, 0x6f, 0x6f, 0x00, 0x41, 0x0a, 0x2a ]"
result_5:
value: "[1, 0x55, '▒,3', 3] == [ 0x01, 0x55, 0xe2, 0x96, 0x92, 0x2c, 0x33, 0x03 ]"
'''
content = MemoryContent(b'')
kstruct = KaitaiStruct(definitions)
parsed = kstruct.parse(content)
self.assertEqual(parsed.result_0.value, b'')
self.assertEqual(parsed.result_1.value, b'CAFE\x00BABE')
definitions = '''
seq:
- id: indexes
type: u1
repeat: eos
instances:
table:
value: "[ [ 1, 2, 3 ], [ 4, 5, 6 ], [ 7, 8, 9 ] ]"
ref:
value: indexes
result_0:
value: table
result_1:
value: ref
result_2:
value: table[indexes[0]][indexes[1] - 1]
result_3:
value: table[indexes[0]][ref[1]]
'''
content = MemoryContent(b'\x01\x02\x03\x04')
kstruct = KaitaiStruct(definitions)
parsed = kstruct.parse(content)
self.assertEqual(parsed.result_0.value.value, b'\x01\x02\x03\x04\x05\x06\x07\x08\x09')
self.assertEqual(type(parsed.result_1).__name__, 'RecordDelayed') # result_1
self.assertEqual(type(parsed.result_1.value).__name__, 'RecordDelayed') # result_1.ref
self.assertEqual(type(parsed.result_1.value.value).__name__, 'RecordList') # result_1.ref.table
self.assertEqual(parsed.result_1.value.value[3].value, 0x04)
self.assertEqual(parsed.result_2.value, 5)
self.assertEqual(parsed.result_3.value, 6)
def testArithmeticOperators(self):
"""Compute with arithmetic operators."""
# Cf. 6.3.1. Arithmetic operators
definitions = '''
seq:
- id: op0
type: u1
- id: op1
type: u1
instances:
result_0:
value: op0 + op1 * 3
result_1:
value: (2 + op0) * op1
result_2:
value: 7 * 2.0
result_3:
value: 7 / 2.0
result_4:
value: -5 % 3
result_5:
value: 4 % 3
result_6:
value: 6 - 3 - -4.0
'''
content = MemoryContent(b'\x02\x03\x04\x05')
kstruct = KaitaiStruct(definitions)
parsed = kstruct.parse(content)
self.assertEqual(parsed.result_0.value, 11)
self.assertEqual(parsed.result_1.value, 12)
self.assertEqual(parsed.result_2.value, 14.0)
self.assertEqual(parsed.result_3.value, 3.5)
self.assertEqual(parsed.result_4.value, 1)
self.assertEqual(parsed.result_5.value, 1)
self.assertEqual(parsed.result_6.value, 7.0)
definitions = '''
seq:
- id: base
size: 3
instances:
result_0:
value: "'xXx ' + base + ' -- %< --'"
'''
content = MemoryContent(b'ABC')
kstruct = KaitaiStruct(definitions)
parsed = kstruct.parse(content)
self.assertEqual(parsed.result_0.value, b'xXx ABC -- %< --')
definitions = '''
seq:
- id: nums
type: u1
repeat: eos
instances:
computed:
value: nums[0] + nums[3]
computed2:
value: nums[0] * nums.size + nums[3]
computed3:
value: nums[0] * nums[nums.size - 1]
'''
kstruct = KaitaiStruct(definitions)
content = MemoryContent(b'\x01\x02\x03\x04')
parsed = kstruct.parse(content)
self.assertEqual(parsed.computed.value, 5)
self.assertEqual(parsed.computed2.value, 8)
self.assertEqual(parsed.computed3.value, 4)
def testRelationalOperators(self):
"""Compute with relational operators."""
# Cf. 6.3.2. Relational operators
definitions = '''
seq:
- id: op0
type: u1
- id: op1
type: u1
- id: op2
size: 3
instances:
result0:
value: op0 == op1
result1:
value: op0 != op1
result2:
value: op2 == 'ABC'
result3:
value: op2 < 'ABCD'
result4:
value: (op0 + 1) >= op1
result5:
value: "(op0 + 1) == 'ABC'.length"
'''
content = MemoryContent(b'\x02\x03ABCD')
kstruct = KaitaiStruct(definitions)
parsed = kstruct.parse(content)
self.assertFalse(parsed.result0.value)
self.assertTrue(parsed.result1.value)
self.assertTrue(parsed.result2.value)
self.assertTrue(parsed.result3.value)
self.assertTrue(parsed.result4.value)
self.assertTrue(parsed.result5.value)
def testBitwiseOperators(self):
"""Compute with bitwise operators."""
# Cf. 6.3.3. Bitwise operators
definitions = '''
seq:
- id: op0
type: u1
- id: op1
type: u1
- id: op2
type: u1
instances:
result_0:
value: op0 & op1
result_1:
value: op1 << op0 >> 1
result_2:
value: (op2 | 0x80) >> 1
'''
content = MemoryContent(b'\x02\x07\x01')
kstruct = KaitaiStruct(definitions)
parsed = kstruct.parse(content)
self.assertEqual(parsed.result_0.value, 0x2)
self.assertEqual(parsed.result_1.value, 14)
self.assertEqual(parsed.result_2.value, 0x40)
def testLogicalOperators(self):
"""Compute with logical boolean operators."""
# Cf. 6.3.4. Logical (boolean) operators
definitions = '''
seq:
- id: op0
type: u1
- id: op1
type: u1
instances:
result_0:
value: (op0 > 0) and not false
result_1:
value: op0 == 1 or op1 == 2
'''
content = MemoryContent(b'\x01\x02')
kstruct = KaitaiStruct(definitions)
parsed = kstruct.parse(content)
self.assertTrue(parsed.result_0.value)
self.assertTrue(parsed.result_1.value)
def testTernaryOperator(self):
"""Offer challenges to the ternary operator."""
# Cf. 6.3.5. Ternary (if-then-else) operator
definitions = '''
seq:
- id: op0
type: u1
- id: op1
type: u1
- id: op2
type: u1
instances:
result_0:
value: 'op0 == 0x80 ? op1 + 1 : op1 * op2'
result_1:
value: 'op0 < 0x80 ? op1 + 1 : op1 * op2'
result_1:
value: 'op0 < 0x80 ? op1 + 1 : op1 * op2'
result_2:
value: '(op0 + 0x10) >= 0x90 ? true : 123'
result_3:
value: '(op0 + 0x10) >= 0x90 and false ? true : 123'
'''
content = MemoryContent(b'\x80\x03\x04')
kstruct = KaitaiStruct(definitions)
parsed = kstruct.parse(content)
self.assertEqual(parsed.result_0.value, 4)
self.assertEqual(parsed.result_1.value, 12)
self.assertTrue(parsed.result_2.value)
self.assertEqual(parsed.result_3.value, 123)
def testIntegersMethods(self):
"""Run methods from integers."""
# Cf. 6.4.1. Integers
definitions = '''
instances:
bytes1:
value: 123.to_s == "123" and -123.to_s == '-123'
'''
content = MemoryContent(b'')
kstruct = KaitaiStruct(definitions)
parsed = kstruct.parse(content)
self.assertTrue(parsed.bytes1.value)
def testFloatsMethods(self):
"""Run methods from floating numbers."""
# Cf. 6.4.2. Floating point numbers
definitions = '''
instances:
result_0:
value: 2.32.to_i == 2 and -7.0.to_i == -7
'''
content = MemoryContent(b'')
kstruct = KaitaiStruct(definitions)
parsed = kstruct.parse(content)
self.assertTrue(parsed.result_0.value)
def XXXtestByteArraysAndStringsMethods(self):
"""Run methods from byte arrays and strings."""
# Cf. 6.4.3. Byte arrays
# 6.4.4. Strings
definitions = '''
instances:
result_1:
value: '[].length == 0'
result_2:
value: "'edcba'.reverse == 'XXabcdeXX'.substring(2, 6)"
result_3:
value: "'123'.to_i == 123 and '-123'.to_i == -123"
result_4:
value: "[ 0x50, 0x72, 0x65, 0x73, 0x65, 0x6e, 0x74, 0x61, 0x63, 0x69, 0xc3, 0xb3, 0x6e, 0x2e, 0x73, 0x78, 0x69 ].to_s('utf-8')"
result_5:
value: "'1010'.to_i(2) == 10 and 'cc'.to_i(16) == 204"
'''
content = MemoryContent(b'')
kstruct = KaitaiStruct(definitions)
parsed = kstruct.parse(content)
self.assertTrue(parsed.result_1.value)
self.assertTrue(parsed.result_2.value)
self.assertTrue(parsed.result_3.value)
# Cf. https://docs.gtk.org/glib/character-set.html
# https://developer-old.gnome.org/glib/stable/glib-Character-Set-Conversion.html#g-convert
self.assertEqual(parsed.result_4.value.decode('utf-8'), 'Presentación.sxi')
self.assertTrue(parsed.result_5.value)
def __passed__testEnumsMethods(self):
"""Run methods from booleans."""
# Cf. 6.4.5. Enums
pass
def testBooleansMethods(self):
"""Run methods from booleans."""
# Cf. 6.4.6. Booleans
definitions = '''
instances:
result_0:
value: true.to_i == 1
result_1:
value: (1 == 2).to_i == 0
'''
content = MemoryContent(b'')
kstruct = KaitaiStruct(definitions)
parsed = kstruct.parse(content)
self.assertTrue(parsed.result_0.value)
self.assertTrue(parsed.result_1.value)
def testUserDefinedTypes(self):
"""Retrieve user-defined types."""
# Cf. 6.4.7. User-defined types
definitions = '''
instances:
result_0:
value: _root
'''
content = MemoryContent(b'')
kstruct = KaitaiStruct(definitions)
parsed = kstruct.parse(content)
self.assertEqual(parsed.result_0.value, parsed)
def __passed__testArraysMethods(self):
"""Run methods from arrays."""
# Cf. 6.4.8. Array types
pass
def __passed__testStreamsMethods(self):
"""Run methods from streams."""
# Cf. 6.4.9. Streams
pass
##############################
### 7. Advanced techniques
##############################
def testSwitchOverStrings(self):
"""Switch over strings."""
# Cf. 7.1.1. Switching over strings
definitions = '''
seq:
- id: rec_type
type: strz
- id: body
type:
switch-on: rec_type
cases:
'"KETCHUP"': rec_type_1
'"MUSTARD"': rec_type_2
'"GUACAMOLE"': rec_type_3
types:
rec_type_1:
instances:
direct:
value: 1
rec_type_2:
instances:
direct:
value: 2
rec_type_3:
instances:
direct:
value: 3
'''
kstruct = KaitaiStruct(definitions)
content = MemoryContent(b'GUACAMOLE\x00')
parsed = kstruct.parse(content)
self.assertEqual(parsed.rec_type.value, b'GUACAMOLE')
self.assertEqual(parsed.body.direct.value, 3)
def testSwitchOverEnums(self):
"""Switch over enumerations."""
# Cf. 7.1.2. Switching over enums
definitions = '''
seq:
- id: rec_type
type: u1
enum: media
- id: body
type:
switch-on: rec_type
cases:
'media::cdrom': rec_type_1
'media::dvdrom': rec_type_2
'media::cassette': rec_type_3
types:
rec_type_1:
instances:
direct:
value: 1
rec_type_2:
instances:
direct:
value: 2
rec_type_3:
instances:
direct:
value: 3
enums:
media:
1: cdrom
2: dvdrom
3: cassette
'''
kstruct = KaitaiStruct(definitions)
content = MemoryContent(b'\x01')
parsed = kstruct.parse(content)
self.assertEqual(parsed.rec_type.value, 1)
self.assertEqual(parsed.body.direct.value, 1)
def testFourCC(self):
"""Recognize four character code."""
# Cf. 7.1.3. FourCC
definitions = '''
seq:
- id: fourcc
type: u4le
enum: pixel_formats
- id: len
type: u1
- id: body
size: len
type:
switch-on: fourcc
cases:
'pixel_formats::rgb2': block_rgb2
'pixel_formats::rle4': block_rle4
'pixel_formats::rle8': block_rle8
types:
block_rgb2:
instances:
direct:
value: 2
block_rle4:
instances:
direct:
value: 4
block_rle8:
instances:
direct:
value: 8
enums:
pixel_formats:
0x32424752: rgb2
0x34454C52: rle4
0x38454C52: rle8
'''
kstruct = KaitaiStruct(definitions)
content = MemoryContent(b'RLE4\x05ABCDE')
parsed = kstruct.parse(content)
self.assertEqual(parsed.fourcc.value, 0x34454C52)
self.assertEqual(parsed.len.value, 0x5)
self.assertEqual(parsed.body.direct.value, 4)
def testNothing(self):
"""Do nothing."""
# Cf. 7.2. Do nothing
definitions = '''
seq:
- id: field_0
size: 1
- id: field_1
type: dummy_1
- id: field_2
type: dummy_2
- id: field_3
type: dummy_3
- id: field_4
type: dummy_4
- id: field_5
size: 1
types:
# One can use empty JSON object syntax to avoid specifying any of
# `seq`, `instances`, etc, sections.
dummy_1: {}
# One can use explicit doc to note that there's nothing there.
dummy_2:
doc: This type is intentionally left blank.
# One can use empty `seq` or `instances` or `types` section, any
# other empty sections, or any combination of thereof.
dummy_3:
seq: []
instances: {}
types: {}
# One can use a very explicit notion of the fact that we want to parse 0 bytes.
dummy_4:
seq:
- id: no_value
size: 0
'''
content = MemoryContent(b'az')
kstruct = KaitaiStruct(definitions)
parsed = kstruct.parse(content)
self.assertEqual(parsed.field_0.value, b'a')
self.assertEqual(type(parsed.field_1).__name__, 'RecordEmpty')
self.assertEqual(parsed.field_1.range.length, 0)
self.assertEqual(type(parsed.field_2).__name__, 'RecordEmpty')
self.assertEqual(parsed.field_2.range.length, 0)
self.assertEqual(type(parsed.field_3).__name__, 'RecordEmpty')
self.assertEqual(parsed.field_3.range.length, 0)
self.assertEqual(type(parsed.field_4.no_value).__name__, 'RecordEmpty')
self.assertEqual(parsed.field_4.no_value.range.length, 0)
self.assertEqual(parsed.field_5.value, b'z')
def testConsumeIncludeTerminators(self):
"""Consume and/or include terminators."""
# Cf. 7.3.1. Terminator: consume or include?
definitions = '''
seq:
- id: str1
type: str
terminator: 0x2e # `.`
- id: str2
type: str
terminator: 0x2e # `.`
'''
kstruct = KaitaiStruct(definitions)
content = MemoryContent(b'foo.bar.')
parsed = kstruct.parse(content)
self.assertEqual(parsed.str1.value, b'foo')
self.assertEqual(parsed.str2.value, b'bar')
definitions = '''
seq:
- id: str1
type: str
terminator: 0x2e # `.`
include: true
- id: str2
type: str
terminator: 0x2e # `.`
eos-error: false
'''
kstruct = KaitaiStruct(definitions)
content = MemoryContent(b'foo.bar')
parsed = kstruct.parse(content)
self.assertEqual(parsed.str1.value, b'foo.')
self.assertEqual(parsed.str2.value, b'bar')
definitions = '''
seq:
- id: str1
type: str
terminator: 0x2e # `.`
consume: false
- id: the_rest
type: str
size-eos: true
'''
kstruct = KaitaiStruct(definitions)
content = MemoryContent(b'foo.bar.')
parsed = kstruct.parse(content)
self.assertEqual(parsed.str1.value, b'foo')
self.assertEqual(parsed.the_rest.value, b'.bar.')
definitions = '''
seq:
- id: str1
type: str
terminator: .
- id: the_rest
type: str
size-eos: true
'''
kstruct = KaitaiStruct(definitions)
content = MemoryContent(b'foo.bar.')
parsed = kstruct.parse(content)
self.assertEqual(parsed.str1.value, b'foo')
self.assertEqual(parsed.the_rest.value, b'bar.')
definitions = '''
seq:
- id: str1
type: str
terminator: xxx.
- id: the_rest
type: str
size-eos: true
'''
kstruct = KaitaiStruct(definitions)
content = MemoryContent(b'fooxxx.bar.')
parsed = kstruct.parse(content)
self.assertEqual(parsed.str1.value, b'foo')
self.assertEqual(parsed.the_rest.value, b'bar.')
def testIgnoreErrorsInDelimitedStructures(self):
"""Ignore errors in delimited structures."""
# Cf. 7.3.2. Ignoring errors in delimited structures
definitions = '''
seq:
- id: my_string
type: str
terminator: 0
eos-error: false
'''
kstruct = KaitaiStruct(definitions)
content = MemoryContent(b'\x61\x62\x63\x00\x64\x65\x66')
parsed = kstruct.parse(content)
self.assertEqual(parsed.my_string.value, b'abc')
kstruct = KaitaiStruct(definitions)
content = MemoryContent(b'\x61\x62\x63\x00')
parsed = kstruct.parse(content)
self.assertEqual(parsed.my_string.value, b'abc')
kstruct = KaitaiStruct(definitions)
content = MemoryContent(b'\x61\x62\x63')
parsed = kstruct.parse(content)
self.assertEqual(parsed.my_string.value, b'abc')
def __passed__testImportTypesFromOtherFiles(self):
"""Import types from other files."""
# Cf. 7.4. Importing types from other files
pass
def __passed__testPlugExternalCodeForOpaqueTypes(self):
"""Plug external code for opaque types."""
# Cf. 7.5. Opaque types: plugging in external code
pass
def __passed__testCustomProcessingRoutines(self):
"""Handle custom processing routines."""
# Cf. 7.6. Custom processing routines
pass
def __passed__testParentTypeEnforcing(self):
"""Enforce parent type."""
# Cf. 7.7. Enforcing parent type
pass
def testTypecasting(self):
"""Ensure there is no need for typecasting."""
# Cf. 7.8. Typecasting
definitions = '''
seq:
- id: num_sections
type: u1
- id: sections
type: section
repeat: expr
repeat-expr: num_sections
types:
section:
seq:
- id: sect_type
type: u1
- id: body
type:
switch-on: sect_type
cases:
1: sect_header
2: sect_color_data
sect_header:
seq:
- id: width
type: u1
- id: height
type: u1
sect_color_data:
seq:
- id: rgb
size: 3
instances:
check_0:
value: sections[0].body.width * sections[0].body.height
check_1:
value: sections[1].body.rgb
check_2:
value: sections[2].body.width * sections[2].body.height
check_3:
value: sections[3].body.rgb
'''
kstruct = KaitaiStruct(definitions)
content = MemoryContent(b'\x04\x01\x02\x04\x02ABC\x01\x03\x05\x02UVW')
parsed = kstruct.parse(content)
# Vérifications externes
self.assertEqual(parsed.num_sections.value, 4)
self.assertEqual(len(parsed.sections), 4)
self.assertEqual(parsed.sections[0].body.width.value + parsed.sections[0].body.height.value, 6)
self.assertEqual(parsed.sections[1].body.rgb.value, b'ABC')
self.assertEqual(parsed.sections[2].body.width.value + parsed.sections[2].body.height.value, 8)
self.assertEqual(parsed.sections[3].body.rgb.value, b'UVW')
# Vérifications internes
self.assertEqual(parsed.check_0.value, 8)
self.assertEqual(parsed.check_1.value.value, b'ABC')
self.assertEqual(parsed.check_2.value, 15)
self.assertEqual(parsed.check_3.value.value, b'UVW')
##########################
### 8. Common pitfalls
##########################
def testReadTypeWithSubstream(self):
"""Read user-type with substream."""
# Cf. 8.1. Specifying size creates a substream
definitions = '''
seq:
- id: header
size: 4
- id: block
type: block
size: 4 # <= important size designation, creates a substream
instances:
byte_3:
pos: 3
type: u1
types:
block:
instances:
byte_3:
pos: 3
type: u1
byte_3_alt:
io: _root._io # <= thanks to this, always points to a byte in main stream
pos: 3
type: u1
'''
kstruct = KaitaiStruct(definitions)
content = MemoryContent(b'\x00\x01\x02\x03\x04\x05\x06\x07')
parsed = kstruct.parse(content)
self.assertEqual(parsed.header.value, b'\x00\x01\x02\x03')
self.assertEqual(parsed.byte_3.value, 0x03)
self.assertEqual(parsed.block.byte_3.value, 0x07)
self.assertEqual(parsed.block.byte_3_alt.value, 0x03)
definitions = '''
seq:
- id: header
size: 4
- id: block
type: block
instances:
byte_3:
pos: 3
type: u1
types:
block:
instances:
byte_3:
pos: 3
type: u1
byte_3_alt:
io: _root._io # <= thanks to this, always points to a byte in main stream
pos: 3
type: u1
'''
kstruct = KaitaiStruct(definitions)
content = MemoryContent(b'\x00\x01\x02\x03\x04\x05\x06\x07')
parsed = kstruct.parse(content)
self.assertEqual(parsed.header.value, b'\x00\x01\x02\x03')
self.assertEqual(parsed.byte_3.value, 0x03)
self.assertEqual(parsed.block.byte_3.value, 0x03)
self.assertEqual(parsed.block.byte_3_alt.value, 0x03)
def testReadTypeWithoutSubstream(self):
"""Read user-type without substream."""
# Cf. 8.2. Not specifying size does not create a substream
definitions = '''
seq:
- id: header
size: 2
- id: block_as_type1
type: type1
size: 2 # <= important, creates a substream
types:
type1:
seq:
- id: val1
size: 2
type2:
seq:
- id: val2
size: 2
instances:
block_as_type2:
io: block_as_type1._io
pos: 0
type: type2
internal_check:
value: block_as_type2._io == _root._io
'''
kstruct = KaitaiStruct(definitions)
content = MemoryContent(b'aabb')
parsed = kstruct.parse(content)
self.assertEqual(parsed.header.value, b'aa')
self.assertEqual(parsed.block_as_type1.val1.value, b'bb')
self.assertEqual(parsed.block_as_type2.val2.value, b'bb')
self.assertFalse(parsed.internal_check.value)
definitions = '''
seq:
- id: header
size: 2
- id: block_as_type1
type: type1
types:
type1:
seq:
- id: val1
size: 2
type2:
seq:
- id: val2
size: 2
instances:
block_as_type2:
io: block_as_type1._io
pos: 0
type: type2
internal_check:
value: block_as_type2._io == _root._io
'''
kstruct = KaitaiStruct(definitions)
content = MemoryContent(b'aabb')
parsed = kstruct.parse(content)
self.assertEqual(parsed.header.value, b'aa')
self.assertEqual(parsed.block_as_type1.val1.value, b'bb')
self.assertEqual(parsed.block_as_type2.val2.value, b'aa')
self.assertTrue(parsed.internal_check.value)
def __passed__testSizedProcess(self):
"""Provide a sized data to processing."""
# Cf. 8.3. Applying process without a size
pass
def __passed__testRelatedKeys(self):
"""Check refering keys and their related YAML nodes."""
# Cf. 8.4. Keys relating to the whole array and to each element in repeated attributes
pass
#######################
### x. Extra checks
#######################
def testMssingField(self):
"""Raise error on missing field."""
definitions = '''
seq:
- id: field0
size-eos: true
'''
kstruct = KaitaiStruct(definitions)
content = MemoryContent(b'\x01\x02\x02\x03')
parsed = kstruct.parse(content)
self.assertIsNotNone(parsed)
self.assertEqual(parsed.field0.creator.raw_id, 'field0')
self.assertEqual(parsed.field0.value, b'\x01\x02\x02\x03')
# AttributeError: 'pychrysalide.plugins.kaitai.records.RecordList' object has no attribute 'xxxx'
with self.assertRaisesRegex(AttributeError, "object has no attribute 'xxxx'"):
print(parsed.xxxx)
def testLEB128Values(self):
"""Read some Little Endian Base 128 values."""
definitions = '''
seq:
- id: groups
type: group
repeat: until
repeat-until: not _.has_next
types:
group:
-webide-representation: '{value}'
doc: |
One byte group, clearly divided into 7-bit "value" chunk and 1-bit "continuation" flag.
seq:
- id: b
type: u1
instances:
has_next:
value: (b & 0b1000_0000) != 0
doc: If true, then we have more bytes to read
value:
value: b & 0b0111_1111
doc: The 7-bit (base128) numeric value chunk of this group
instances:
len:
value: groups.size
value:
value: >-
groups[0].value
+ (len >= 2 ? (groups[1].value << 7) : 0)
+ (len >= 3 ? (groups[2].value << 14) : 0)
+ (len >= 4 ? (groups[3].value << 21) : 0)
+ (len >= 5 ? (groups[4].value << 28) : 0)
+ (len >= 6 ? (groups[5].value << 35) : 0)
+ (len >= 7 ? (groups[6].value << 42) : 0)
+ (len >= 8 ? (groups[7].value << 49) : 0)
doc: Resulting unsigned value as normal integer
sign_bit:
value: '1 << (7 * len - 1)'
value_signed:
value: '(value ^ sign_bit) - sign_bit'
doc-ref: https://graphics.stanford.edu/~seander/bithacks.html#VariableSignExtend
'''
kstruct = KaitaiStruct(definitions)
content = MemoryContent(b'\xe5\x8e\x26')
parsed = kstruct.parse(content)
self.assertEqual(parsed.len.value, 3)
self.assertEqual(parsed.value.value, parsed.value_signed.value)
self.assertEqual(parsed.value.value, 624485)
content = MemoryContent(b'\xc0\xbb\x78')
parsed = kstruct.parse(content)
self.assertEqual(parsed.len.value, 3)
self.assertNotEqual(parsed.value.value, parsed.value_signed.value)
self.assertEqual(parsed.value_signed.value, -123456)