view contrib/wix/README.txt @ 30443:2e484bdea8c4

zstd: vendor zstd 1.1.1

zstd is a new compression format and it is awesome, yielding
higher compression ratios and significantly faster compression
and decompression operations compared to zlib (our current
compression engine of choice) across the board.

We want zstd to be a 1st class citizen in Mercurial and to eventually
be the preferred compression format for various operations.

This patch starts the formal process of supporting zstd by vendoring
a copy of zstd. Why do we need to vendor zstd? Good question.

First, zstd is relatively new and not widely available yet. If we
didn't vendor zstd or distribute it with Mercurial, most users likely
wouldn't have zstd installed or even available to install. What good
is a feature if you can't use it? Vendoring and distributing the zstd
sources gives us the highest liklihood that zstd will be available to
Mercurial installs.

Second, the Python bindings to zstd (which will be vendored in a
separate changeset) make use of zstd APIs that are only available
via static linking. One reason they are only available via static
linking is that they are unstable and could change at any time.
While it might be possible for the Python bindings to attempt to
talk to different versions of the zstd C library, the safest thing to
do is link against a specific, known-working version of zstd. This
is why the Python zstd bindings themselves vendor zstd and why we
must as well. This also explains why the added files are in a
"python-zstandard" directory.

The added files are from the 1.1.1 release of zstd (Git commit
4c0b44f8ced84c4c8edfa07b564d31e4fa3e8885 from
https://github.com/facebook/zstd) and are added without modifications.
Not all files from the zstd "distribution" have been added. Notably
missing are files to support interacting with "legacy," pre-1.0
versions of zstd. The decision of which files to include is made by
the upstream python-zstandard project (which I'm the author of). The
files in this commit are a snapshot of the files from the 0.5.0
release of that project, Git commit
e637c1b214d5f869cf8116c550dcae23ec13b677 from
https://github.com/indygreg/python-zstandard.

WiX installer source files
==========================

The files in this folder are used by the thg-winbuild [1] package
building architecture to create a Mercurial MSI installer.   These files
are versioned within the Mercurial source tree because the WXS files
must kept up to date with distribution changes within their branch.  In
other words, the default branch WXS files are expected to diverge from
the stable branch WXS files.  Storing them within the same repository is
the only sane way to keep the source tree and the installer in sync.

The MSI installer builder uses only the mercurial.ini file from the
contrib/win32 folder, the contents of which have been historically used
to create an InnoSetup based installer.  The rest of the files there are
ignored.

The MSI packages built by thg-winbuild require elevated (admin)
privileges to be installed due to the installation of MSVC CRT libraries
under the C:\WINDOWS\WinSxS folder.  Thus the InnoSetup installers may
still be useful to some users.

To build your own MSI packages, clone the thg-winbuild [1] repository
and follow the README.txt [2] instructions closely.  There are fewer
prerequisites for a WiX [3] installer than an InnoSetup installer, but
they are more specific.

Direct questions or comments to Steve Borho <[e-mail]>

[1] http://bitbucket.org/tortoisehg/thg-winbuild
[2] http://bitbucket.org/tortoisehg/thg-winbuild/src/tip/README.txt
[3] http://wix.sourceforge.net/