# HG changeset patch
# User Jan Pipek <jan.pipek@gmail.com>
# Date 1568368254 -7200
# Fri Sep 13 11:50:54 2019 +0200
# Node ID 4329c4c1b263de4c6275e5b2d65574d0d38f446b
# Parent 7dec84bf88d88a3f084bd2c03e9733a3eaae3371
Address several pull requests comments + hide asSeekableStream
diff --git a/pyasn1/codec/ber/decoder.py b/pyasn1/codec/ber/decoder.py
--- a/pyasn1/codec/ber/decoder.py
+++ b/pyasn1/codec/ber/decoder.py
@@ -6,7 +6,7 @@
#
import os
import sys
-from io import BytesIO, BufferedReader, IOBase
+from io import BytesIO, BufferedReader, IOBase, DEFAULT_BUFFER_SIZE
from pyasn1 import debug
from pyasn1 import error
@@ -22,28 +22,31 @@
from pyasn1.type import useful
-__all__ = ['decodeStream']
+__all__ = ['decodeStream', 'decode']
LOG = debug.registerLoggee(__name__, flags=debug.DEBUG_DECODER)
noValue = base.noValue
-_MAX_BUFFER_SIZE = 1024
_PY2 = sys.version_info < (3,)
-class _CachedStreamWrapper(IOBase):
- """Wrapper around non-seekable streams."""
+class _CachingStreamWrapper(IOBase):
+ """Wrapper around non-seekable streams.
+
+ Note that the implementation is tied to the decoder,
+ not checking for dangerous arguments for the sake
+ of performance.
+ """
def __init__(self, raw):
self._raw = raw
self._cache = BytesIO()
- self._marked_position_ = 0
+ self._markedPosition_ = 0
def peek(self, n):
- pos = self._cache.tell()
result = self.read(n)
- self._cache.seek(pos, os.SEEK_SET)
+ self._cache.seek(-len(result), os.SEEK_CUR)
return result
def seekable(self):
@@ -61,37 +64,32 @@
return read_from_cache + read_from_raw
@property
- def _marked_position(self):
+ def _markedPosition(self):
# This closely corresponds with how _marked_position attribute
# is manipulated with in Decoder.__call__ and (indefLen)ValueDecoder's
- return self._marked_position_
-
- @_marked_position.setter
- def _marked_position(self, value):
- self._marked_position_ = value
- self.seek(value)
- self.reset()
+ return self._markedPosition_
- def tell(self):
- return self._cache.tell()
-
- def reset(self):
- """Keep the buffered data reasonably large.
+ @_markedPosition.setter
+ def _markedPosition(self, value):
+ self._markedPosition_ = value
+ self.seek(value)
- Whenever we se _marked_position, we know for sure
- that we will not return back, and thus it is
- safe to drop all cached data.
- """
- if self._cache.tell() > _MAX_BUFFER_SIZE:
+ # Whenever we set _marked_position, we know for sure
+ # that we will not return back, and thus it is
+ # safe to drop all cached data.
+ if self._cache.tell() > DEFAULT_BUFFER_SIZE:
current = self._cache.read()
self._cache.seek(0, os.SEEK_SET)
self._cache.truncate()
self._cache.write(current)
self._cache.seek(0, os.SEEK_SET)
- self._marked_position_ = 0
+ self._markedPosition_ = 0
+
+ def tell(self):
+ return self._cache.tell()
-def asSeekableStream(substrate):
+def _asSeekableStream(substrate):
"""Convert object to seekable byte-stream.
Parameters
@@ -113,11 +111,11 @@
return BytesIO(substrate.asOctets())
try:
if _PY2 and isinstance(substrate, file): # Special case (it is not possible to set attributes)
- return BufferedReader(substrate, _MAX_BUFFER_SIZE)
+ return BufferedReader(substrate)
elif substrate.seekable(): # Will fail for most invalid types
return substrate
else:
- return _CachedStreamWrapper(substrate)
+ return _CachingStreamWrapper(substrate)
except AttributeError:
raise UnsupportedSubstrateError("Cannot convert " + substrate.__class__.__name__ + " to a seekable bit stream.")
@@ -839,7 +837,7 @@
containerValue):
component = decodeFun(
- asSeekableStream(containerValue[pos].asOctets()),
+ _asSeekableStream(containerValue[pos].asOctets()),
asn1Spec=openType, **options
)
@@ -847,7 +845,7 @@
else:
component = decodeFun(
- asSeekableStream(asn1Object.getComponentByPosition(idx).asOctets()),
+ _asSeekableStream(asn1Object.getComponentByPosition(idx).asOctets()),
asn1Spec=openType, **options
)
@@ -1023,7 +1021,7 @@
containerValue):
component = decodeFun(
- asSeekableStream(containerValue[pos].asOctets()),
+ _asSeekableStream(containerValue[pos].asOctets()),
asn1Spec=openType, **dict(options, allowEoo=True)
)
@@ -1031,7 +1029,7 @@
else:
component = decodeFun(
- asSeekableStream(asn1Object.getComponentByPosition(idx).asOctets()),
+ _asSeekableStream(asn1Object.getComponentByPosition(idx).asOctets()),
asn1Spec=openType, **dict(options, allowEoo=True)
)
@@ -1221,7 +1219,7 @@
isUntagged = tagSet != asn1Spec.tagSet
if isUntagged:
- fullPosition = substrate._marked_position
+ fullPosition = substrate._markedPosition
currentPosition = substrate.tell()
substrate.seek(fullPosition, os.SEEK_SET)
@@ -1260,7 +1258,7 @@
else:
# TODO: Seems not to be tested
- fullPosition = substrate._marked_position
+ fullPosition = substrate._markedPosition
currentPosition = substrate.tell()
substrate.seek(fullPosition, os.SEEK_SET)
@@ -1462,7 +1460,7 @@
tagCache = self.__tagCache
tagSetCache = self.__tagSetCache
- substrate._marked_position = substrate.tell()
+ substrate._markedPosition = substrate.tell()
while state is not stStop:
@@ -1756,7 +1754,7 @@
"""Iterator of objects in a substrate."""
# TODO: This should become `decode` after API-breaking approved
try:
- substrate = asSeekableStream(substrate)
+ substrate = _asSeekableStream(substrate)
except TypeError:
raise PyAsn1Error
while True:
@@ -1820,7 +1818,7 @@
def decode(substrate, asn1Spec=None, **kwargs):
# TODO: Temporary solution before merging with upstream
# It preserves the original API
- substrate = asSeekableStream(substrate)
+ substrate = _asSeekableStream(substrate)
value = _decode(substrate, asn1Spec=asn1Spec, **kwargs)
return value, substrate.read()
diff --git a/pyasn1/codec/cer/decoder.py b/pyasn1/codec/cer/decoder.py
--- a/pyasn1/codec/cer/decoder.py
+++ b/pyasn1/codec/cer/decoder.py
@@ -8,7 +8,7 @@
from pyasn1 import error
from pyasn1.codec.ber import decoder
-from pyasn1.codec.ber.decoder import asSeekableStream
+from pyasn1.codec.ber.decoder import _asSeekableStream
from pyasn1.compat.octets import oct2int
from pyasn1.type import univ
@@ -70,7 +70,7 @@
def decodeStream(substrate, asn1Spec=None, **kwargs):
"""Iterator of objects in a substrate."""
# TODO: This should become `decode` after API-breaking approved
- substrate = asSeekableStream(substrate)
+ substrate = _asSeekableStream(substrate)
while True:
result = _decode(substrate, asn1Spec, **kwargs)
if result is None:
@@ -132,6 +132,6 @@
def decode(substrate, asn1Spec=None, **kwargs):
# TODO: Temporary solution before merging with upstream
# It preserves the original API
- substrate = asSeekableStream(substrate)
+ substrate = _asSeekableStream(substrate)
value = _decode(substrate, asn1Spec=asn1Spec, **kwargs)
return value, substrate.read()
diff --git a/pyasn1/codec/der/decoder.py b/pyasn1/codec/der/decoder.py
--- a/pyasn1/codec/der/decoder.py
+++ b/pyasn1/codec/der/decoder.py
@@ -6,7 +6,7 @@
#
from io import BytesIO
-from pyasn1.codec.ber.decoder import asSeekableStream
+from pyasn1.codec.ber.decoder import _asSeekableStream
from pyasn1.codec.cer import decoder
from pyasn1.type import univ
@@ -50,7 +50,7 @@
def decodeStream(substrate, asn1Spec=None, **kwargs):
"""Iterator of objects in a substrate."""
# TODO: This should become `decode` after API-breaking approved
- substrate = asSeekableStream(substrate)
+ substrate = _asSeekableStream(substrate)
while True:
result = _decode(substrate, asn1Spec, **kwargs)
if result is None:
@@ -112,6 +112,6 @@
def decode(substrate, asn1Spec=None, **kwargs):
# TODO: Temporary solution before merging with upstream
# It preserves the original API
- substrate = asSeekableStream(substrate)
+ substrate = _asSeekableStream(substrate)
value = _decode(substrate, asn1Spec=asn1Spec, **kwargs)
return value, substrate.read()
\ No newline at end of file
diff --git a/tests/codec/ber/test_decoder.py b/tests/codec/ber/test_decoder.py
--- a/tests/codec/ber/test_decoder.py
+++ b/tests/codec/ber/test_decoder.py
@@ -1603,7 +1603,7 @@
def testErrorCondition(self):
decode = decoder.Decoder(decoder.tagMap, decoder.typeMap)
substrate = b'abc'
- stream = decoder.asSeekableStream(substrate)
+ stream = decoder._asSeekableStream(substrate)
try:
asn1Object = decode(stream)
@@ -1619,7 +1619,7 @@
def testRawDump(self):
decode = decoder.Decoder(decoder.tagMap, decoder.typeMap)
substrate = ints2octs((31, 8, 2, 1, 1, 131, 3, 2, 1, 12))
- stream = decoder.asSeekableStream(substrate, )
+ stream = decoder._asSeekableStream(substrate, )
decode.defaultErrorState = decoder.stDumpRawValue