FM / howto

/usr/share/doc/git/howto

Name	Size	Mode	Actions
coordinate-embargoed-releases.html	29838	0644	edit dl rm
coordinate-embargoed-releases.txt	10823	0644	edit dl rm
keep-canonical-history-correct.html	26249	0644	edit dl rm
keep-canonical-history-correct.txt	6795	0644	edit dl rm
maintain-git.html	41732	0644	edit dl rm
maintain-git.txt	18220	0644	edit dl rm
new-command.html	22001	0644	edit dl rm
new-command.txt	4460	0644	edit dl rm
rebase-from-internal-branch.html	24456	0644	edit dl rm
rebase-from-internal-branch.txt	6310	0644	edit dl rm
rebuild-from-update-hook.html	20387	0644	edit dl rm
rebuild-from-update-hook.txt	3137	0644	edit dl rm
recover-corrupted-blob-object.html	23884	0644	edit dl rm
recover-corrupted-blob-object.txt	5510	0644	edit dl rm
recover-corrupted-object-harder.html	36038	0644	edit dl rm
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separating-topic-branches.html	20526	0644	edit dl rm
separating-topic-branches.txt	3356	0644	edit dl rm
setup-git-server-over-http.html	30562	0644	edit dl rm
setup-git-server-over-http.txt	8613	0644	edit dl rm
update-hook-example.html	23272	0644	edit dl rm
update-hook-example.txt	6289	0644	edit dl rm
use-git-daemon.html	19649	0644	edit dl rm
use-git-daemon.txt	2135	0644	edit dl rm
using-merge-subtree.html	20235	0644	edit dl rm
using-merge-subtree.txt	3025	0644	edit dl rm
using-signed-tag-in-pull-request.html	26765	0644	edit dl rm
using-signed-tag-in-pull-request.txt	8282	0644	edit dl rm

Edit: /usr/share/doc/git/howto/rebuild-from-update-hook.html (20387B)

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<body class="article">
<div id="header">
<h1>How to rebuild from update hook</h1>
<span id="revdate"></span>
</div>
<div id="content">
<div id="preamble">
<div class="sectionbody">
<div class="paragraph"><p>The pages under <a href="https://www.kernel.org/pub/software/scm/git/docs/">https://www.kernel.org/pub/software/scm/git/docs/</a>
are built from Documentation/ directory of the git.git project
and needed to be kept up-to-date.  The www.kernel.org/ servers
are mirrored and I was told that the origin of the mirror is on
the machine $some.kernel.org, on which I was given an account
when I took over Git maintainership from Linus.</p></div>
<div class="paragraph"><p>The directories relevant to this how-to are these two:</p></div>
<div class="literalblock">
<div class="content">
<pre><code>/pub/scm/git/git.git/       The public Git repository.
/pub/software/scm/git/docs/ The HTML documentation page.</code></pre>
</div></div>
<div class="paragraph"><p>So I made a repository to generate the documentation under my
home directory over there.</p></div>
<div class="literalblock">
<div class="content">
<pre><code>$ cd
$ mkdir doc-git &amp;&amp; cd doc-git
$ git clone /pub/scm/git/git.git/ docgen</code></pre>
</div></div>
<div class="paragraph"><p>What needs to happen is to update the $HOME/doc-git/docgen/
working tree, build HTML docs there and install the result in
/pub/software/scm/git/docs/ directory.  So I wrote a little
script:</p></div>
<div class="literalblock">
<div class="content">
<pre><code>$ cat &gt;dododoc.sh &lt;&lt;\EOF
#!/bin/sh
cd $HOME/doc-git/docgen || exit</code></pre>
</div></div>
<div class="literalblock">
<div class="content">
<pre><code>unset GIT_DIR</code></pre>
</div></div>
<div class="literalblock">
<div class="content">
<pre><code>git pull /pub/scm/git/git.git/ master &amp;&amp;
cd Documentation &amp;&amp;
make install-webdoc
EOF</code></pre>
</div></div>
<div class="paragraph"><p>Initially I used to run this by hand whenever I push into the
public Git repository.  Then I did a cron job that ran twice a
day.  The current round uses the post-update hook mechanism,
like this:</p></div>
<div class="literalblock">
<div class="content">
<pre><code>$ cat &gt;/pub/scm/git/git.git/hooks/post-update &lt;&lt;\EOF
#!/bin/sh
#
# An example hook script to prepare a packed repository for use over
# dumb transports.
#
# To enable this hook, make this file executable by "chmod +x post-update".</code></pre>
</div></div>
<div class="literalblock">
<div class="content">
<pre><code>case " $* " in
*' refs/heads/master '*)
        echo $HOME/doc-git/dododoc.sh | at now
        ;;
esac
exec git-update-server-info
EOF
$ chmod +x /pub/scm/git/git.git/hooks/post-update</code></pre>
</div></div>
<div class="paragraph"><p>There are four things worth mentioning:</p></div>
<div class="ulist"><ul>
<li>
<p>
The update-hook is run after the repository accepts a "git
   push", under my user privilege.  It is given the full names
   of refs that have been updated as arguments.  My post-update
   runs the dododoc.sh script only when the master head is
   updated.
</p>
</li>
<li>
<p>
When update-hook is run, GIT_DIR is set to <em>.</em> by the calling
   receive-pack.  This is inherited by the dododoc.sh run via
   the "at" command, and needs to be unset; otherwise, "git
   pull" it does into $HOME/doc-git/docgen/ repository would not
   work correctly.
</p>
</li>
<li>
<p>
The stdout of update hook script is not connected to git
   push; I run the heavy part of the command inside "at", to
   receive the execution report via e-mail.
</p>
</li>
<li>
<p>
This is still crude and does not protect against simultaneous
   make invocations stomping on each other.  I would need to add
   some locking mechanism for this.
</p>
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Last updated
 2025-06-13 22:14:31 UTC
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How to rebuild from update hook

The pages under https://www.kernel.org/pub/software/scm/git/docs/ are built from Documentation/ directory of the git.git project and needed to be kept up-to-date. The www.kernel.org/ servers are mirrored and I was told that the origin of the mirror is on the machine $some.kernel.org, on which I was given an account when I took over Git maintainership from Linus.

The directories relevant to this how-to are these two:

/pub/scm/git/git.git/       The public Git repository.
/pub/software/scm/git/docs/ The HTML documentation page.

So I made a repository to generate the documentation under my home directory over there.

$ cd
$ mkdir doc-git && cd doc-git
$ git clone /pub/scm/git/git.git/ docgen

What needs to happen is to update the $HOME/doc-git/docgen/ working tree, build HTML docs there and install the result in /pub/software/scm/git/docs/ directory. So I wrote a little script:

$ cat >dododoc.sh <<\EOF
#!/bin/sh
cd $HOME/doc-git/docgen || exit

unset GIT_DIR

git pull /pub/scm/git/git.git/ master &&
cd Documentation &&
make install-webdoc
EOF

Initially I used to run this by hand whenever I push into the public Git repository. Then I did a cron job that ran twice a day. The current round uses the post-update hook mechanism, like this:

$ cat >/pub/scm/git/git.git/hooks/post-update <<\EOF
#!/bin/sh
#
# An example hook script to prepare a packed repository for use over
# dumb transports.
#
# To enable this hook, make this file executable by "chmod +x post-update".

case " $* " in
*' refs/heads/master '*)
        echo $HOME/doc-git/dododoc.sh | at now
        ;;
esac
exec git-update-server-info
EOF
$ chmod +x /pub/scm/git/git.git/hooks/post-update

There are four things worth mentioning:

The update-hook is run after the repository accepts a "git push", under my user privilege. It is given the full names of refs that have been updated as arguments. My post-update runs the dododoc.sh script only when the master head is updated.
When update-hook is run, GIT_DIR is set to . by the calling receive-pack. This is inherited by the dododoc.sh run via the "at" command, and needs to be unset; otherwise, "git pull" it does into $HOME/doc-git/docgen/ repository would not work correctly.
The stdout of update hook script is not connected to git push; I run the heavy part of the command inside "at", to receive the execution report via e-mail.
This is still crude and does not protect against simultaneous make invocations stomping on each other. I would need to add some locking mechanism for this.