cosmopolitan/third_party/python
Justine Tunney 00611e9b06 Improve ZIP filesystem and change its prefix
The ZIP filesystem has a breaking change. You now need to use /zip/ to
open() / opendir() / etc. assets within the ZIP structure of your APE
binary, instead of the previous convention of using zip: or zip! URIs.
This is needed because Python likes to use absolute paths, and having
ZIP paths encoded like URIs simply broke too many things.

Many more system calls have been updated to be able to operate on ZIP
files and file descriptors. In particular fcntl() and ioctl() since
Python would do things like ask if a ZIP file is a terminal and get
confused when the old implementation mistakenly said yes, because the
fastest way to guarantee native file descriptors is to dup(2). This
change also improves the async signal safety of zipos and ensures it
doesn't maintain any open file descriptors beyond that which the user
has opened.

This change makes a lot of progress towards adding magic numbers that
are specific to platforms other than Linux. The philosophy here is that,
if you use an operating system like FreeBSD, then you should be able to
take advantage of FreeBSD exclusive features, even if we don't polyfill
them on other platforms. For example, you can now open() a file with the
O_VERIFY flag. If your program runs on other platforms, then Cosmo will
automatically set O_VERIFY to zero. This lets you safely use it without
the need for #ifdef or ifstatements which detract from readability.

One of the blindspots of the ASAN memory hardening we use to offer Rust
like assurances has always been that memory passed to the kernel via
system calls (e.g. writev) can't be checked automatically since the
kernel wasn't built with MODE=asan. This change makes more progress
ensuring that each system call will verify the soundness of memory
before it's passed to the kernel. The code for doing these checks is
fast, particularly for buffers, where it can verify 64 bytes a cycle.

- Correct O_LOOP definition on NT
- Introduce program_executable_name
- Add ASAN guards to more system calls
- Improve termios compatibility with BSDs
- Fix bug in Windows auxiliary value encoding
- Add BSD and XNU specific errnos and open flags
- Add check to ensure build doesn't talk to internet
2021-08-22 01:11:53 -07:00
..
Include Improve Libc by making Python work even better 2021-08-18 22:16:23 -07:00
Lib Improve ZIP filesystem and change its prefix 2021-08-22 01:11:53 -07:00
Modules Improve ZIP filesystem and change its prefix 2021-08-22 01:11:53 -07:00
Objects Improve ZIP filesystem and change its prefix 2021-08-22 01:11:53 -07:00
Parser Improve ZIP filesystem and change its prefix 2021-08-22 01:11:53 -07:00
PC Make whitespace changes 2021-08-13 03:20:45 -07:00
Programs Improve ZIP filesystem and change its prefix 2021-08-22 01:11:53 -07:00
Python Improve ZIP filesystem and change its prefix 2021-08-22 01:11:53 -07:00
Tools Fix a few more Python tests 2021-08-16 23:47:47 -07:00
.gitattributes Perform build and magnum tuning 2021-08-10 10:26:13 -07:00
LICENSE python-3.6.zip added from Github 2021-08-09 05:39:42 -07:00
pycomp.c Improve ZIP filesystem and change its prefix 2021-08-22 01:11:53 -07:00
pyconfig.h Improve ZIP filesystem and change its prefix 2021-08-22 01:11:53 -07:00
pydump.py Experiment with making Python go faster 2021-08-18 21:57:11 -07:00
python.mk Improve ZIP filesystem and change its prefix 2021-08-22 01:11:53 -07:00
README.cosmo Improve ZIP filesystem and change its prefix 2021-08-22 01:11:53 -07:00
README.rst python-3.6.zip added from Github 2021-08-09 05:39:42 -07:00

This is Python version 3.6.14+
==============================

.. image:: https://travis-ci.org/python/cpython.svg?branch=3.6
   :alt: CPython build status on Travis CI
   :target: https://travis-ci.org/python/cpython

.. image:: https://ci.appveyor.com/api/projects/status/4mew1a93xdkbf5ua/branch/3.6?svg=true
   :alt: CPython build status on Appveyor
   :target: https://ci.appveyor.com/project/python/cpython/branch/3.6

.. image:: https://dev.azure.com/python/cpython/_apis/build/status/Azure%20Pipelines%20CI?branchName=3.6
   :alt: CPython build status on Azure Pipelines
   :target: https://dev.azure.com/python/cpython/_build/latest?definitionId=4&branchName=3.6

.. image:: https://codecov.io/gh/python/cpython/branch/3.6/graph/badge.svg
   :alt: CPython code coverage on Codecov
   :target: https://codecov.io/gh/python/cpython

Copyright (c) 2001-2021 Python Software Foundation.  All rights reserved.

See the end of this file for further copyright and license information.

General Information
-------------------

- Website: https://www.python.org
- Source code: https://github.com/python/cpython
- Issue tracker: https://bugs.python.org
- Documentation: https://docs.python.org
- Developer's Guide: https://devguide.python.org/

Contributing to CPython
-----------------------

For more complete instructions on contributing to CPython development,
see the `Developer Guide`_.

.. _Developer Guide: https://devguide.python.org/

Using Python
------------

Installable Python kits, and information about using Python, are available at
`python.org`_.

.. _python.org: https://www.python.org/


Build Instructions
------------------

On Unix, Linux, BSD, macOS, and Cygwin::

    ./configure
    make
    make test
    sudo make install

This will install Python as ``python3``.

You can pass many options to the configure script; run ``./configure --help``
to find out more.  On macOS and Cygwin, the executable is called ``python.exe``;
elsewhere it's just ``python``.

If you are running on macOS with the latest updates installed, make sure to install
openSSL or some other SSL software along with Homebrew or another package manager.
If issues persist, see https://devguide.python.org/setup/#macos-and-os-x for more
information.

On macOS, if you have configured Python with ``--enable-framework``, you
should use ``make frameworkinstall`` to do the installation.  Note that this
installs the Python executable in a place that is not normally on your PATH,
you may want to set up a symlink in ``/usr/local/bin``.

On Windows, see `PCbuild/readme.txt
<https://github.com/python/cpython/blob/3.6/PCbuild/readme.txt>`_.

If you wish, you can create a subdirectory and invoke configure from there.
For example::

    mkdir debug
    cd debug
    ../configure --with-pydebug
    make
    make test

(This will fail if you *also* built at the top-level directory.  You should do
a ``make clean`` at the toplevel first.)

To get an optimized build of Python, ``configure --enable-optimizations``
before you run ``make``.  This sets the default make targets up to enable
Profile Guided Optimization (PGO) and may be used to auto-enable Link Time
Optimization (LTO) on some platforms.  For more details, see the sections
below.


Profile Guided Optimization
---------------------------

PGO takes advantage of recent versions of the GCC or Clang compilers.  If used,
either via ``configure --enable-optimizations`` above or by manually running
``make profile-opt`` regardless of configure flags it will do several steps.

First, the entire Python directory is cleaned of temporary files that may have
resulted in a previous compilation.

Then, an instrumented version of the interpreter is built, using suitable
compiler flags for each flavour. Note that this is just an intermediary step.
The binary resulting from this step is not good for real life workloads as
it has profiling instructions embedded inside.

After this instrumented version of the interpreter is built, the Makefile will
automatically run a training workload. This is necessary in order to profile
the interpreter execution. Note also that any output, both stdout and stderr,
that may appear at this step is suppressed.

Finally, the last step is to rebuild the interpreter, using the information
collected in the previous one. The end result will be a Python binary that is
optimized and suitable for distribution or production installation.


Link Time Optimization
----------------------

Enabled via configure's ``--with-lto`` flag.  LTO takes advantage of the
ability of recent compiler toolchains to optimize across the otherwise
arbitrary ``.o`` file boundary when building final executables or shared
libraries for additional performance gains.


What's New
----------

We have a comprehensive overview of the changes in the `What's New in Python
3.6 <https://docs.python.org/3.6/whatsnew/3.6.html>`_ document.  For a more
detailed change log, read `Misc/NEWS
<https://github.com/python/cpython/blob/3.6/Misc/NEWS.d>`_, but a full
accounting of changes can only be gleaned from the `commit history
<https://github.com/python/cpython/commits/3.6>`_.

If you want to install multiple versions of Python see the section below
entitled "Installing multiple versions".


Documentation
-------------

`Documentation for Python 3.6 <https://docs.python.org/3.6/>`_ is online,
updated daily.

It can also be downloaded in many formats for faster access.  The documentation
is downloadable in HTML, PDF, and reStructuredText formats; the latter version
is primarily for documentation authors, translators, and people with special
formatting requirements.

For information about building Python's documentation, refer to `Doc/README.rst
<https://github.com/python/cpython/blob/3.6/Doc/README.rst>`_.


Converting From Python 2.x to 3.x
---------------------------------

Significant backward incompatible changes were made for the release of Python
3.0, which may cause programs written for Python 2 to fail when run with Python
3.  For more information about porting your code from Python 2 to Python 3, see
the `Porting HOWTO <https://docs.python.org/3/howto/pyporting.html>`_.


Testing
-------

To test the interpreter, type ``make test`` in the top-level directory.  The
test set produces some output.  You can generally ignore the messages about
skipped tests due to optional features which can't be imported.  If a message
is printed about a failed test or a traceback or core dump is produced,
something is wrong.

By default, tests are prevented from overusing resources like disk space and
memory.  To enable these tests, run ``make testall``.

If any tests fail, you can re-run the failing test(s) in verbose mode.  For
example, if ``test_os`` and ``test_gdb`` failed, you can run::

    make test TESTOPTS="-v test_os test_gdb"

If the failure persists and appears to be a problem with Python rather than
your environment, you can `file a bug report <https://bugs.python.org>`_ and
include relevant output from that command to show the issue.

See `Running & Writing Tests <https://devguide.python.org/runtests/>`_
for more on running tests.

Installing multiple versions
----------------------------

On Unix and Mac systems if you intend to install multiple versions of Python
using the same installation prefix (``--prefix`` argument to the configure
script) you must take care that your primary python executable is not
overwritten by the installation of a different version.  All files and
directories installed using ``make altinstall`` contain the major and minor
version and can thus live side-by-side.  ``make install`` also creates
``${prefix}/bin/python3`` which refers to ``${prefix}/bin/pythonX.Y``.  If you
intend to install multiple versions using the same prefix you must decide which
version (if any) is your "primary" version.  Install that version using ``make
install``.  Install all other versions using ``make altinstall``.

For example, if you want to install Python 2.7, 3.5, and 3.6 with 3.6 being the
primary version, you would execute ``make install`` in your 3.6 build directory
and ``make altinstall`` in the others.


Issue Tracker and Mailing List
------------------------------

Bug reports are welcome!  You can use the `issue tracker
<https://bugs.python.org>`_ to report bugs, and/or submit pull requests `on
GitHub <https://github.com/python/cpython>`_.

You can also follow development discussion on the `python-dev mailing list
<https://mail.python.org/mailman/listinfo/python-dev/>`_.


Proposals for enhancement
-------------------------

If you have a proposal to change Python, you may want to send an email to the
comp.lang.python or `python-ideas`_ mailing lists for initial feedback.  A
Python Enhancement Proposal (PEP) may be submitted if your idea gains ground.
All current PEPs, as well as guidelines for submitting a new PEP, are listed at
`python.org/dev/peps/ <https://www.python.org/dev/peps/>`_.

.. _python-ideas: https://mail.python.org/mailman/listinfo/python-ideas/


Release Schedule
----------------

See :pep:`494` for Python 3.6 release details.


Copyright and License Information
---------------------------------

Copyright (c) 2001-2021 Python Software Foundation.  All rights reserved.

Copyright (c) 2000 BeOpen.com.  All rights reserved.

Copyright (c) 1995-2001 Corporation for National Research Initiatives.  All
rights reserved.

Copyright (c) 1991-1995 Stichting Mathematisch Centrum.  All rights reserved.

See the file "LICENSE" for information on the history of this software, terms &
conditions for usage, and a DISCLAIMER OF ALL WARRANTIES.

This Python distribution contains *no* GNU General Public License (GPL) code,
so it may be used in proprietary projects.  There are interfaces to some GNU
code but these are entirely optional.

All trademarks referenced herein are property of their respective holders.