X-Git-Url: http://www.git.cypherpunks.ru/?p=pyderasn.git;a=blobdiff_plain;f=doc%2Ffeatures.rst;h=fd7bb7d71df35a275abdf52c5e8d904fa6fd62dd;hp=34fe9419d3b6f4aa30dcc9f19a52c6843d68570c;hb=HEAD;hpb=13ea772db7870683065ac15197888cd037df78f0

diff --git a/doc/features.rst b/doc/features.rst
index 34fe941..5cfabee 100644
--- a/doc/features.rst
+++ b/doc/features.rst
@@ -1,15 +1,19 @@
+.. _features:
+
 Features
 ========
 
-* BER/CER/DER decoding, DER encoding
+* BER/CER/DER decoding, strict DER validation, DER/CER encoding
 * Basic ASN.1 data types (X.208): BOOLEAN, INTEGER, BIT STRING, OCTET
   STRING, NULL, OBJECT IDENTIFIER, ENUMERATED, all strings, UTCTime,
   GeneralizedTime, CHOICE, ANY, SEQUENCE (OF), SET (OF)
 * Size :ref:`constraints <bounds>` checking
 * Working with sequences as high level data objects with ability to
   (un)marshall them
-* Python 2.7/3.5/3.6 compatibility
+* Python 3.5+ compatibility (2.7 dropped in version 9.0)
 * Aimed to be complaint with `X.690-201508 <https://www.itu.int/rec/T-REC-X.690-201508-I/en>`__
+* Streaming decoding and encoding capabilities, allowing working with
+  very small memory footprint
 
 Why yet another library? `pyasn1 <http://snmplabs.com/pyasn1/>`__
 had all of this a long time ago. PyDERASN resembles it in many ways. In
@@ -18,7 +22,6 @@ practice it should be relatively easy to convert ``pyasn1``'s code to
 Also there is `asn1crypto <https://github.com/wbond/asn1crypto>`__.
 
 * Small, simple and trying to be reviewable code. Just a single file
-  with `six <https://pypi.org/project/six/>`__ dependency
 * Ability to know :ref:`exact decoded <decoding>` objects offsets and
   lengths inside the binary
 * Automatic decoding of :ref:`DEFINED BY <definedby>` fields
@@ -34,10 +37,19 @@ Also there is `asn1crypto <https://github.com/wbond/asn1crypto>`__.
   structures allow BER encoding for the whole message, except for
   ``SignedAttributes`` -- you can easily verify your CMS satisfies that
   requirement
+* Ability to use mmap-ed files, memoryviews, iterators, 2-pass DER
+  encoding mode and CER encoder dealing with the writer, giving ability
+  to create huge ASN.1 encoded files with very little memory footprint
+* Ability to decode files in event generation mode, without the need to
+  keep all the data and decoded structures (that takes huge quantity of
+  memory in all known ASN.1 libraries) in the memory
+* ``__slots__``, ``copy.copy()`` friendliness
+* Workability with ``pickle``
+* `Cython <https://cython.org/>`__ compatibility
 * Extensive and comprehensive
   `hypothesis <https://hypothesis.readthedocs.io/en/master/>`__
   driven tests coverage. It also has been fuzzed with
-  `python-afl <http://jwilk.net/software/python-afl>`__.
+  `python-afl <http://jwilk.net/software/python-afl>`__
 * Some kind of strong typing: SEQUENCEs require the exact **type** of
   settable values, even when they are inherited (assigning ``Integer``
   to the field with the type ``CMSVersion(Integer)`` is not allowed)
@@ -47,38 +59,20 @@ Also there is `asn1crypto <https://github.com/wbond/asn1crypto>`__.
   automatically set required tags)
 * Descriptive errors, like ``pyderasn.DecodeError: UTCTime
   (tbsCertificate:validity:notAfter:utcTime) (at 328) invalid UTCTime format``
-* ``__slots__`` friendliness
+* Could be significantly :ref:`faster <performance>` and have lower memory usage
 * :ref:`Pretty printer <pprinting>` and
   :ref:`command-line decoder <cmdline>`, that could
   conveniently replace utilities like either ``dumpasn1`` or
   ``openssl asn1parse``
-* Could be significantly faster and have lower memory usage.
-  For example parsing of CACert.org's CRL (8.48 MiB) on FreeBSD 12.0
-  amd64, Intel Core i5-6200U 2.3 GHz machine, Python 3.5.5/2.7.15:
 
-  .. list-table::
-     :widths: 15 45 20 20
-     :header-rows: 1
+  .. figure:: pprinting.webp
+     :alt: Pretty printing example output
 
-     * - Library
-       - Command
-       - Time, sec (Py3/Py2)
-       - Memory used, MiB (Py3/Py2)
-     * - pyasn1 0.4.5
-       - ``der_decode(data, asn1Spec=rfc5280.CertificateList())``
-       - 1257 / 1302
-       - 1327 / 2093
-     * - asn1crypto 0.24.0
-       - ``asn1crypto.crl.CertificateList.load(data).native``
-       - 29.3 / 43.8
-       - 983 / 1677
-     * - pyderasn 4.9
-       - ``CertificateList().decode(data)`` (CertificateList is
-         converted ``pyasn1`` scheme definition)
-       - 27.6 / 32.5
-       - 498 / 488
+     An example of pretty printed X.509 certificate with automatically
+     parsed DEFINED BY fields.
+* :ref:`ASN.1 browser <browser>`
 
-There are drawbacks:
+  .. figure:: browser.webp
+     :alt: ASN.1 browser example
 
-* No old Python versions support
-* See :ref:`limitations <limitations>`
+     An example of browser running.