view contrib/packaging/inno/readme.rst @ 52284:f4aede0f01af

rust-manifest: use `memchr` crate for all byte-finding needs

While writing a very dumb manifest diffing algorithm for a proof-of-concept
I saw that `Manifest::find_by_path` was much slower than I was expecting.

It turns out that the Rust stdlib uses slow (all is relative) code when
searching for byte positions for reasons ranging from portability, SIMD
API stability, nobody doing the work, etc. `memch` is much faster for these
purposes, so let's use it.

I was measuring ~670ms of profile time in `find_by_path`, after this patch
it went down to ~230ms.

Requirements
============

Building the Inno installer requires a Windows machine.

The following system dependencies must be installed:

* Inno Setup (http://jrsoftware.org/isdl.php) version 5.4 or newer.
  Be sure to install the optional Inno Setup Preprocessor feature,
  which is required.
* Python 3.8+ (to run the ``packaging.py`` script)

Building
========

The ``packaging.py`` script automates the process of producing an Inno
installer. It manages fetching and configuring non-system dependencies
(such as gettext, and various Python packages).  It can be run from a
basic cmd.exe Window (i.e. activating the MSBuildTools environment is
not required).

From the prompt, change to the Mercurial source directory. e.g.
``cd c:\src\hg``.

Next, invoke ``packaging.py`` to produce an Inno installer.::

   $ py -3 contrib\packaging\packaging.py \
       inno --pyoxidizer-target x86_64-pc-windows-msvc

If everything runs as intended, dependencies will be fetched and
configured into the ``build`` sub-directory, Mercurial will be built,
and an installer placed in the ``dist`` sub-directory. The final line
of output should print the name of the generated installer.

Additional options may be configured. Run ``packaging.py inno --help``
to see a list of program flags.

MinGW
=====

It is theoretically possible to generate an installer that uses
MinGW. This isn't well tested and ``packaging.py`` and may properly
support it. See old versions of this file in version control for
potentially useful hints as to how to achieve this.