GitまわりあれこれAdvent Calendar 2024

.git感想文

Last updated at 2024-12-01Posted at 2024-12-01

Gitまわりあれこれ Calendar 2024
https://qiita.com/advent-calendar/2024/lizhi05853-git
Day 1 投稿記事です。

Calendar開設、記事投稿ありがとうございます。

記事をお読みになられたら、Calendarにあってもいいかなって記事には、いいね💚　をお願いします。

gitは、人が書いたスクリプトを利用しているだけです。
自分では1mmも書いたことがなく、勉強のために描かせてください。

分類

分類がWeテクノロジーにあるのは違和感があった。

GitLab Calendar 2024
https://qiita.com/advent-calendar/2024/gitlab
DevOps・インフラ・SRE

GitHub Calendar 2024
https://qiita.com/advent-calendar/2024/github
サービス・アプリケーション

自分がインフラ屋であることや、gitはサービスだと思っている。
GitLab、GitHubの分類はそれもあるかなってなってる。

.gitの中身を見てみる

Day1
https://qiita.com/lizhi05853/items/ca9e7d321a56248f5da6

.git/hooks ディレクトリ配下はサンプルっぽいので割愛します

sampleだから説明が欲しいと思う。
あとで、自分なりに書いてみます。

git init

# git --version
git version 2.39.5
# git init
hint: Using 'master' as the name for the initial branch. This default branch name
hint: is subject to change. To configure the initial branch name to use in all
hint: of your new repositories, which will suppress this warning, call:
hint: 
hint: 	git config --global init.defaultBranch <name>
hint: 
hint: Names commonly chosen instead of 'master' are 'main', 'trunk' and
hint: 'development'. The just-created branch can be renamed via this command:
hint: 
hint: 	git branch -m <name>
Initialized empty Git repository in /tmp/llm/new/.git/

# cd hooks
# ls
applypatch-msg.sample	   pre-commit.sample	    prepare-commit-msg.sample
commit-msg.sample	   pre-merge-commit.sample  push-to-checkout.sample
fsmonitor-watchman.sample  pre-push.sample	    update.sample
post-update.sample	   pre-rebase.sample
pre-applypatch.sample	   pre-receive.sample

applypatch-msg.sample

#!/bin/sh
#
# An example hook script to check the commit log message taken by
# applypatch from an e-mail message.
#
# The hook should exit with non-zero status after issuing an
# appropriate message if it wants to stop the commit.  The hook is
# allowed to edit the commit message file.
#
# To enable this hook, rename this file to "applypatch-msg".

. git-sh-setup
commitmsg="$(git rev-parse --git-path hooks/commit-msg)"
test -x "$commitmsg" && exec "$commitmsg" ${1+"$@"}
:

applypatch-msgにRenameして使えって。

commit-msg.sample

#!/bin/sh
#
# An example hook script to check the commit log message.
# Called by "git commit" with one argument, the name of the file
# that has the commit message.  The hook should exit with non-zero
# status after issuing an appropriate message if it wants to stop the
# commit.  The hook is allowed to edit the commit message file.
#
# To enable this hook, rename this file to "commit-msg".

# Uncomment the below to add a Signed-off-by line to the message.
# Doing this in a hook is a bad idea in general, but the prepare-commit-msg
# hook is more suited to it.
#
# SOB=$(git var GIT_AUTHOR_IDENT | sed -n 's/^\(.*>\).*$/Signed-off-by: \1/p')
# grep -qs "^$SOB" "$1" || echo "$SOB" >> "$1"

# This example catches duplicate Signed-off-by lines.

test "" = "$(grep '^Signed-off-by: ' "$1" |
	 sort | uniq -c | sed -e '/^[ 	]*1[ 	]/d')" || {
	echo >&2 Duplicate Signed-off-by lines.
	exit 1
}

fsmonitor-watchman.sample

#!/usr/bin/perl

use strict;
use warnings;
use IPC::Open2;

# An example hook script to integrate Watchman
# (https://facebook.github.io/watchman/) with git to speed up detecting
# new and modified files.
#
# The hook is passed a version (currently 2) and last update token
# formatted as a string and outputs to stdout a new update token and
# all files that have been modified since the update token. Paths must
# be relative to the root of the working tree and separated by a single NUL.
#
# To enable this hook, rename this file to "query-watchman" and set
# 'git config core.fsmonitor .git/hooks/query-watchman'
#
my ($version, $last_update_token) = @ARGV;

# Uncomment for debugging
# print STDERR "$0 $version $last_update_token\n";

# Check the hook interface version
if ($version ne 2) {
	die "Unsupported query-fsmonitor hook version '$version'.\n" .
	    "Falling back to scanning...\n";
}

my $git_work_tree = get_working_dir();

my $retry = 1;

my $json_pkg;
eval {
	require JSON::XS;
	$json_pkg = "JSON::XS";
	1;
} or do {
	require JSON::PP;
	$json_pkg = "JSON::PP";
};

launch_watchman();

sub launch_watchman {
	my $o = watchman_query();
	if (is_work_tree_watched($o)) {
		output_result($o->{clock}, @{$o->{files}});
	}
}

sub output_result {
	my ($clockid, @files) = @_;

	# Uncomment for debugging watchman output
	# open (my $fh, ">", ".git/watchman-output.out");
	# binmode $fh, ":utf8";
	# print $fh "$clockid\n@files\n";
	# close $fh;

	binmode STDOUT, ":utf8";
	print $clockid;
	print "\0";
	local $, = "\0";
	print @files;
}

sub watchman_clock {
	my $response = qx/watchman clock "$git_work_tree"/;
	die "Failed to get clock id on '$git_work_tree'.\n" .
		"Falling back to scanning...\n" if $? != 0;

	return $json_pkg->new->utf8->decode($response);
}

sub watchman_query {
	my $pid = open2(\*CHLD_OUT, \*CHLD_IN, 'watchman -j --no-pretty')
	or die "open2() failed: $!\n" .
	"Falling back to scanning...\n";

	# In the query expression below we're asking for names of files that
	# changed since $last_update_token but not from the .git folder.
	#
	# To accomplish this, we're using the "since" generator to use the
	# recency index to select candidate nodes and "fields" to limit the
	# output to file names only. Then we're using the "expression" term to
	# further constrain the results.
	my $last_update_line = "";
	if (substr($last_update_token, 0, 1) eq "c") {
		$last_update_token = "\"$last_update_token\"";
		$last_update_line = qq[\n"since": $last_update_token,];
	}
	my $query = <<"	END";
		["query", "$git_work_tree", {$last_update_line
			"fields": ["name"],
			"expression": ["not", ["dirname", ".git"]]
		}]
	END

	# Uncomment for debugging the watchman query
	# open (my $fh, ">", ".git/watchman-query.json");
	# print $fh $query;
	# close $fh;

	print CHLD_IN $query;
	close CHLD_IN;
	my $response = do {local $/; <CHLD_OUT>};

	# Uncomment for debugging the watch response
	# open ($fh, ">", ".git/watchman-response.json");
	# print $fh $response;
	# close $fh;

	die "Watchman: command returned no output.\n" .
	"Falling back to scanning...\n" if $response eq "";
	die "Watchman: command returned invalid output: $response\n" .
	"Falling back to scanning...\n" unless $response =~ /^\{/;

	return $json_pkg->new->utf8->decode($response);
}

sub is_work_tree_watched {
	my ($output) = @_;
	my $error = $output->{error};
	if ($retry > 0 and $error and $error =~ m/unable to resolve root .* directory (.*) is not watched/) {
		$retry--;
		my $response = qx/watchman watch "$git_work_tree"/;
		die "Failed to make watchman watch '$git_work_tree'.\n" .
		    "Falling back to scanning...\n" if $? != 0;
		$output = $json_pkg->new->utf8->decode($response);
		$error = $output->{error};
		die "Watchman: $error.\n" .
		"Falling back to scanning...\n" if $error;

		# Uncomment for debugging watchman output
		# open (my $fh, ">", ".git/watchman-output.out");
		# close $fh;

		# Watchman will always return all files on the first query so
		# return the fast "everything is dirty" flag to git and do the
		# Watchman query just to get it over with now so we won't pay
		# the cost in git to look up each individual file.
		my $o = watchman_clock();
		$error = $output->{error};

		die "Watchman: $error.\n" .
		"Falling back to scanning...\n" if $error;

		output_result($o->{clock}, ("/"));
		$last_update_token = $o->{clock};

		eval { launch_watchman() };
		return 0;
	}

	die "Watchman: $error.\n" .
	"Falling back to scanning...\n" if $error;

	return 1;
}

sub get_working_dir {
	my $working_dir;
	if ($^O =~ 'msys' || $^O =~ 'cygwin') {
		$working_dir = Win32::GetCwd();
		$working_dir =~ tr/\\/\//;
	} else {
		require Cwd;
		$working_dir = Cwd::cwd();
	}

	return $working_dir;
}

perl 苦手で解読できてません。ごめんなさい。

post-update.sample

#!/bin/sh
#
# An example hook script to prepare a packed repository for use over
# dumb transports.
#
# To enable this hook, rename this file to "post-update".

exec git update-server-info

"post-update"にrenameして使えって。

update.sample

#!/bin/sh
#
# An example hook script to block unannotated tags from entering.
# Called by "git receive-pack" with arguments: refname sha1-old sha1-new
#
# To enable this hook, rename this file to "update".
#
# Config
# ------
# hooks.allowunannotated
#   This boolean sets whether unannotated tags will be allowed into the
#   repository.  By default they won't be.
# hooks.allowdeletetag
#   This boolean sets whether deleting tags will be allowed in the
#   repository.  By default they won't be.
# hooks.allowmodifytag
#   This boolean sets whether a tag may be modified after creation. By default
#   it won't be.
# hooks.allowdeletebranch
#   This boolean sets whether deleting branches will be allowed in the
#   repository.  By default they won't be.
# hooks.denycreatebranch
#   This boolean sets whether remotely creating branches will be denied
#   in the repository.  By default this is allowed.
#

# --- Command line
refname="$1"
oldrev="$2"
newrev="$3"

# --- Safety check
if [ -z "$GIT_DIR" ]; then
	echo "Don't run this script from the command line." >&2
	echo " (if you want, you could supply GIT_DIR then run" >&2
	echo "  $0 <ref> <oldrev> <newrev>)" >&2
	exit 1
fi

if [ -z "$refname" -o -z "$oldrev" -o -z "$newrev" ]; then
	echo "usage: $0 <ref> <oldrev> <newrev>" >&2
	exit 1
fi

# --- Config
allowunannotated=$(git config --type=bool hooks.allowunannotated)
allowdeletebranch=$(git config --type=bool hooks.allowdeletebranch)
denycreatebranch=$(git config --type=bool hooks.denycreatebranch)
allowdeletetag=$(git config --type=bool hooks.allowdeletetag)
allowmodifytag=$(git config --type=bool hooks.allowmodifytag)

# check for no description
projectdesc=$(sed -e '1q' "$GIT_DIR/description")
case "$projectdesc" in
"Unnamed repository"* | "")
	echo "*** Project description file hasn't been set" >&2
	exit 1
	;;
esac

# --- Check types
# if $newrev is 0000...0000, it's a commit to delete a ref.
zero=$(git hash-object --stdin </dev/null | tr '[0-9a-f]' '0')
if [ "$newrev" = "$zero" ]; then
	newrev_type=delete
else
	newrev_type=$(git cat-file -t $newrev)
fi

case "$refname","$newrev_type" in
	refs/tags/*,commit)
		# un-annotated tag
		short_refname=${refname##refs/tags/}
		if [ "$allowunannotated" != "true" ]; then
			echo "*** The un-annotated tag, $short_refname, is not allowed in this repository" >&2
			echo "*** Use 'git tag [ -a | -s ]' for tags you want to propagate." >&2
			exit 1
		fi
		;;
	refs/tags/*,delete)
		# delete tag
		if [ "$allowdeletetag" != "true" ]; then
			echo "*** Deleting a tag is not allowed in this repository" >&2
			exit 1
		fi
		;;
	refs/tags/*,tag)
		# annotated tag
		if [ "$allowmodifytag" != "true" ] && git rev-parse $refname > /dev/null 2>&1
		then
			echo "*** Tag '$refname' already exists." >&2
			echo "*** Modifying a tag is not allowed in this repository." >&2
			exit 1
		fi
		;;
	refs/heads/*,commit)
		# branch
		if [ "$oldrev" = "$zero" -a "$denycreatebranch" = "true" ]; then
			echo "*** Creating a branch is not allowed in this repository" >&2
			exit 1
		fi
		;;
	refs/heads/*,delete)
		# delete branch
		if [ "$allowdeletebranch" != "true" ]; then
			echo "*** Deleting a branch is not allowed in this repository" >&2
			exit 1
		fi
		;;
	refs/remotes/*,commit)
		# tracking branch
		;;
	refs/remotes/*,delete)
		# delete tracking branch
		if [ "$allowdeletebranch" != "true" ]; then
			echo "*** Deleting a tracking branch is not allowed in this repository" >&2
			exit 1
		fi
		;;
	*)
		# Anything else (is there anything else?)
		echo "*** Update hook: unknown type of update to ref $refname of type $newrev_type" >&2
		exit 1
		;;
esac

# --- Finished
exit 0

引数３つ。１つめはrefnameに, ２つめはold-revに、３つめがnew-revに入る。

解読できてないものがあり、続きは続きは明日以降に追記させてください。

<この項は書きかけです。順次追記します。>
This article is not completed. I will add some words and/or centences in order.

今日git(2)でしくったこと: Initialized empty Git repository, warning: adding embedded git repository, error(122)
https://qiita.com/kaizen_nagoya/items/63ce0be02b20e1860c2a

ありがとうGit(15)lab
https://qiita.com/kaizen_nagoya/items/05a39cee0eb3a2de1106

Qiita Calendar 2024

2024 参加・主催Calendarと投稿記事一覧 Qiita(248)
https://qiita.com/kaizen_nagoya/items/d80b8fbac2496df7827f

主催Calendar2024分析 Qiita(254)
https://qiita.com/kaizen_nagoya/items/15807336d583076f70bc

Calendar 統計
https://qiita.com/kaizen_nagoya/items/e315558dcea8ee3fe43e

Large Language Model Related Calendar
https://qiita.com/kaizen_nagoya/items/3beb0bc3fb71e3ae6d66

LLM 関連 Calendar 2024
https://qiita.com/kaizen_nagoya/items/c36033cf66862d5496fa

LLM コミュニティ参加記録作成予定
https://qiita.com/kaizen_nagoya/items/4840ae09437f1e9df74b

博士論文 Calendar 2024 を開催します。
https://qiita.com/kaizen_nagoya/items/51601357efbcaf1057d0

博士論文(0)関連記事一覧
https://qiita.com/kaizen_nagoya/items/8f223a760e607b705e78

2023 Countdown Calendar 主催・参加一覧
https://qiita.com/kaizen_nagoya/items/c4c2f08ac97f38d08543

自己記事一覧

Qiitaで逆リンクを表示しなくなったような気がする。時々、スマフォで表示するとあらわっることがあり、完全に削除したのではなさそう。

４月以降、せっせとリンクリストを作り、統計を取って確率を説明しようとしている。
2025年２月末を目標にしている。

一覧の一覧( The directory of directories of mine.) Qiita(100)
https://qiita.com/kaizen_nagoya/items/7eb0e006543886138f39

仮説（0）一覧（目標100現在40）
https://qiita.com/kaizen_nagoya/items/f000506fe1837b3590df

Qiita(0)Qiita関連記事一覧（自分）
https://qiita.com/kaizen_nagoya/items/58db5fbf036b28e9dfa6

Error一覧 error(0)
https://qiita.com/kaizen_nagoya/items/48b6cbc8d68eae2c42b8

資料集 [あなたもdocker私もdocker一覧] docker(0)
https://qiita.com/kaizen_nagoya/items/45699eefd62677f69c1d

C++ Support(0)　
https://qiita.com/kaizen_nagoya/items/8720d26f762369a80514

Coding(0) Rules, C, Secure, MISRA and so on
https://qiita.com/kaizen_nagoya/items/400725644a8a0e90fbb0

Ethernet 記事一覧　Ethernet(0)
https://qiita.com/kaizen_nagoya/items/88d35e99f74aefc98794

Wireshark 一覧 wireshark(0)、Ethernet(48)
https://qiita.com/kaizen_nagoya/items/fbed841f61875c4731d0

線網（Wi-Fi）空中線(antenna)(0) 記事一覧(118/300目標)
https://qiita.com/kaizen_nagoya/items/5e5464ac2b24bd4cd001

一覧：携帯計画者日記（0）
https://qiita.com/kaizen_nagoya/items/005d38c6f55c85570e74

なぜdockerで機械学習するか書籍・ソース一覧作成中 (目標100)
https://qiita.com/kaizen_nagoya/items/ddd12477544bf5ba85e2

プログラムちょい替え（0）一覧:4件
https://qiita.com/kaizen_nagoya/items/296d87ef4bfd516bc394

言語処理100本ノックをdockerで。python覚えるのに最適。:10+12
https://qiita.com/kaizen_nagoya/items/7e7eb7c543e0c18438c4

Python(0)記事をまとめたい。
https://qiita.com/kaizen_nagoya/items/088c57d70ab6904ebb53

安全（0）安全工学シンポジウムに向けて: 21
https://qiita.com/kaizen_nagoya/items/c5d78f3def8195cb2409

プログラマによる、プログラマのための、統計(0)と確率のプログラミングとその後
https://qiita.com/kaizen_nagoya/items/6e9897eb641268766909

転職(0)一覧
https://qiita.com/kaizen_nagoya/items/f77520d378d33451d6fe

物理記事　上位100
https://qiita.com/kaizen_nagoya/items/66e90fe31fbe3facc6ff

量子(0) 計算機, 量子力学
https://qiita.com/kaizen_nagoya/items/1cd954cb0eed92879fd4

数学関連記事１００
https://qiita.com/kaizen_nagoya/items/d8dadb49a6397e854c6d

統計(0)一覧
https://qiita.com/kaizen_nagoya/items/80d3b221807e53e88aba

図(0) state, sequence and timing. UML and お絵描き
https://qiita.com/kaizen_nagoya/items/60440a882146aeee9e8f

品質一覧
https://qiita.com/kaizen_nagoya/items/2b99b8e9db6d94b2e971

言語・文学記事　１００
https://qiita.com/kaizen_nagoya/items/42d58d5ef7fb53c407d6

医工連携関連記事一覧
https://qiita.com/kaizen_nagoya/items/6ab51c12ba51bc260a82

自動車　記事　１００
https://qiita.com/kaizen_nagoya/items/f7f0b9ab36569ad409c5

通信記事１００
https://qiita.com/kaizen_nagoya/items/1d67de5e1cd207b05ef7

日本語（０）一欄
https://qiita.com/kaizen_nagoya/items/7498dcfa3a9ba7fd1e68

英語(0) 一覧
https://qiita.com/kaizen_nagoya/items/680e3f5cbf9430486c7d

音楽　一覧(0)
https://qiita.com/kaizen_nagoya/items/b6e5f42bbfe3bbe40f5d

「@kazuo_reve 新人の方によく展開している有益な情報」確認一覧
https://qiita.com/kaizen_nagoya/items/b9380888d1e5a042646b

鉄道（０）鉄道のシステム考察はてっちゃんがてつだってくれる
https://qiita.com/kaizen_nagoya/items/faa4ea03d91d901a618a

OSEK OS設計の基礎　OSEK(100)
https://qiita.com/kaizen_nagoya/items/7528a22a14242d2d58a3

coding (101) 一覧を作成し始めた。omake:最近のQiitaで表示しない5つの事象
https://qiita.com/kaizen_nagoya/items/20667f09f19598aedb68

官公庁・学校・公的団体（NPOを含む）システムの課題、官（０）
https://qiita.com/kaizen_nagoya/items/04ee6eaf7ec13d3af4c3

「はじめての」シリーズ　ベクタージャパン　
https://qiita.com/kaizen_nagoya/items/2e41634f6e21a3cf74eb

AUTOSAR(0)Qiita記事一覧, OSEK(75)
https://qiita.com/kaizen_nagoya/items/89c07961b59a8754c869

プログラマが知っていると良い「公序良俗」
https://qiita.com/kaizen_nagoya/items/9fe7c0dfac2fbd77a945

LaTeX(0) 一覧　
https://qiita.com/kaizen_nagoya/items/e3f7dafacab58c499792

自動制御、制御工学一覧（０）
https://qiita.com/kaizen_nagoya/items/7767a4e19a6ae1479e6b

Rust(0) 一覧　
https://qiita.com/kaizen_nagoya/items/5e8bb080ba6ca0281927

.git感想文

分類

.gitの中身を見てみる

git init

git関連

Qiita Calendar 2024

自己記事一覧

関連資料

Engineering Festa 2024前に必読記事一覧

文書履歴(document history)

最後までおよみいただきありがとうございました。

Thank you very much for reading to the last sentence.