From 358c67cc6baecd56540c3fad70a35c73edf8729f Mon Sep 17 00:00:00 2001
From: Roman Zhuravlev <rozhur@zhira.net>
Date: Wed, 23 Apr 2025 23:16:55 +0500
Subject: [PATCH] Initial commit

---
 .gitignore |   1 +
 Makefile   |  12 ++++
 README.md  |  71 +++++++++++++++++++++
 mca.sh     | 177 +++++++++++++++++++++++++++++++++++++++++++++++++++++
 screenrc   |  44 +++++++++++++
 5 files changed, 305 insertions(+)
 create mode 100644 .gitignore
 create mode 100644 Makefile
 create mode 100644 README.md
 create mode 100755 mca.sh
 create mode 100644 screenrc

diff --git a/.gitignore b/.gitignore
new file mode 100644
index 0000000..9f11b75
--- /dev/null
+++ b/.gitignore
@@ -0,0 +1 @@
+.idea/
diff --git a/Makefile b/Makefile
new file mode 100644
index 0000000..43b7d86
--- /dev/null
+++ b/Makefile
@@ -0,0 +1,12 @@
+PREFIX ?= /usr
+
+all:
+	@echo Run \'make install\' to install MCA
+
+install:
+	@install -m 0755 mca.sh -D $(DESTDIR)$(PREFIX)/bin/mca
+	@install -m 0644 screenrc -Dt $(DESTDIR)/etc/mca
+
+uninstall:
+	@rm -rf $(DESTDIR)/etc/mca
+	@rm -f $(DESTDIR)$(PREFIX)/bin/mca
diff --git a/README.md b/README.md
new file mode 100644
index 0000000..1838872
--- /dev/null
+++ b/README.md
@@ -0,0 +1,71 @@
+# Minecraft server launcher - utility
+ 
+MCA is easy-to-use and allows you to run a Minecraft server with
+just one short command in the background with the ability to
+view the output with GNU Screen and run commands.
+
+## Usage
+```bash
+mca [-fdx] [MCA_NAME|MCA_JAR|MCA_DIR] [--] [INPUT]…
+```
+
+## MCA examples
+
+### Running `minecraft` server with 2048 megabytes max memory
+```bash
+mkdir ~/mca/myserver
+cd ~/mca/myserver
+# This link is taken from https://www.minecraft.net/en-us/download/server
+wget https://piston-data.mojang.com/v1/objects/e6ec2f64e6080b9b5d9b471b291c33cc7f509733/server.jar
+echo 'MAX_MEMORY=2048M' >> ./.mcarc
+mca
+```
+
+### Running `paper` server with Aikar flags
+```bash
+echo 'PLATFORM=paper' >> ./.mcarc
+mca
+```
+
+### Running `velocity` server with Aikar flags
+```bash
+echo 'PLATFORM=velocity' >> ./.mcarc
+mca
+```
+
+Also, the platform can be determined automatically based on the `.jar` name. For example, the file name is `paper-1.21.5.jar`, since it starts with `paper`, the platform will be `paper` and there is no need to manually specify it in the `PLATFORM` variable.
+
+## Installation
+
+### From Zhira Debian repository
+
+Debian 12 Bookworm has deb packages in the Zhira Debian repository.
+
+#### Add the Zhira Debian repository:
+```bash
+wget -qO- https://deb.zhira.net/debian/zhira.gpg | gpg --dearmor | sudo tee /etc/apt/trusted.gpg.d/zhira.gpg > /dev/null
+echo 'deb [arch=all] https://deb.zhira.net/debian/ bookworm main' | sudo tee /etc/apt/sources.list.d/zhira.list > /dev/null
+```
+
+#### Update the package list
+```bash
+sudo apt update
+```
+
+#### Install `mca`
+```bash
+sudo apt install mca
+```
+
+### From sources
+
+#### Clone the repository
+```bash
+git clone https://git.zhira.net/rozhur/mca
+```
+
+### Install `mca` into `/usr/local/bin` directory
+```bash
+cd ./mca
+sudo make PREFIX=/usr/local install
+```
diff --git a/mca.sh b/mca.sh
new file mode 100755
index 0000000..d8a8bf6
--- /dev/null
+++ b/mca.sh
@@ -0,0 +1,177 @@
+#!/bin/sh
+
+set -e
+
+EXEC_NAME="$(basename -- "$0")"
+
+options="$(getopt -n "$EXEC_NAME" -s sh  -o hvfdx -l help -l version -- "$@")"
+eval set -- "$options"
+
+SCREEN_OPTS=
+
+while :; do
+    case "$1" in
+        -h|--help)
+            echo "Usage: $EXEC_NAME [-fdx] [MCA_NAME|MCA_JAR|MCA_DIR] [--] [INPUT]…"
+            exit
+            ;;
+        -v|--version)
+            echo "MCA 1.0.0"
+            exit
+            ;;
+        -f)
+            SCREEN_OPTS=Dm
+            ;;
+        -d)
+            SCREEN_OPTS=d
+            ;;
+        -x)
+            SCREEN_OPTS=x
+            ;;
+        --)
+            shift
+            break
+    esac
+    shift
+done
+
+MCA_NAME=$1
+
+if [ -z "$MCA_NAME" ]; then
+    MCA_DIR="$PWD"
+    MCA_NAME="$(basename -- "$MCA_DIR")"
+elif echo "$MCA_NAME" | grep -qE '^\.{,2}/' && MCA_NAME="$(readlink -f -- "$MCA_NAME")"; then
+    if [ -d "$MCA_NAME" ]; then
+        MCA_DIR="$MCA_NAME"
+        MCA_NAME="$(basename -- "$MCA_DIR")"
+    else
+        MCA_DIR="$(dirname -- "$MCA_NAME")" MCA_JAR="$MCA_NAME"
+        MCA_NAME="$(basename -- "$MCA_DIR")"
+    fi
+else
+    MCA_DIR="$HOME/mca/$MCA_NAME"
+fi
+
+command -v screen > /dev/null || { echo "$EXEC_NAME: screen not found" >&2; exit 2; }
+
+if [ -n "$2" ]; then
+    shift
+    INPUT="$(echo "$*" | sed 's/"/\\\0/g')"
+    screen -S "$MCA_NAME" -X eval "stuff \"$INPUT\"\\015" > /dev/null || {
+        echo "$EXEC_NAME: no screen found" >&2
+        exit 2
+    }
+    exit
+fi
+
+MCA_SCREENRC_FILE="/etc/mca/screenrc"
+[ -r "$MCA_SCREENRC_FILE" ] || { echo "$EXEC_NAME: can't read $MCA_SCREENRC_FILE" >&2; exit 2; }
+
+if screen -c "$MCA_SCREENRC_FILE" "-$SCREEN_OPTS"rS "$MCA_NAME" > /dev/null 2>&1; then
+    exit
+elif screen -S "$MCA_NAME" -X select . > /dev/null 2>&1; then
+    echo "$EXEC_NAME: this screen has already been attached to someone" >&2
+    exit 2
+fi
+
+[ -d "$MCA_DIR" ] || { echo "$EXEC_NAME: $MCA_DIR: not found" >&2; exit 2; }
+
+cd "$MCA_DIR"
+
+MCA_RC_FILE="$MCA_DIR/.mcarc"
+
+# this file is taken from a dynamic variable, so we cannot specify an explicit path to the file
+# shellcheck disable=SC1090
+# `--` is supported in dash
+# shellcheck disable=SC2240
+[ -e "$MCA_RC_FILE" ] && . -- "$MCA_RC_FILE"
+
+if [ -z "$PLATFORM" ]; then
+    if [ -z "$MCA_JAR" ]; then
+        MCA_JAR="$(find "$MCA_DIR" -maxdepth 1 -type f -name \*.jar | head -1)"
+        [ -z "$MCA_JAR" ] && {
+            echo "$EXEC_NAME: no jar found in $MCA_DIR" >&2
+            exit 2
+        }
+    fi
+
+    if [ -e "$MCA_JAR" ]; then
+        PLATFORM="$(basename -- "$MCA_JAR")"
+        PLATFORM="$(echo "$PLATFORM" | tr '[:upper:]' '[:lower:]' | grep -oE '[a-z]+' | head -1)"
+    else
+        echo "$EXEC_NAME: $MCA_JAR: no such file" >&2
+        exit 2
+    fi
+else
+    [ -z "$MCA_JAR" ] && MCA_JAR="$MCA_DIR/$PLATFORM.jar"
+    [ ! -e "$MCA_JAR" ] && {
+        echo "$EXEC_NAME: $MCA_JAR: no such file" >&2
+        exit 2
+    }
+fi
+
+[ -n "$JVM_FLAGS" ] && JVM_FLAGS="$JVM_FLAGS "
+JVM_FLAGS="$JVM_FLAGS-Dfile.encoding=UTF-8 -Djava.awt.headless=true"
+
+case "$PLATFORM" in
+    bungee)
+        ;;
+    waterfall|velocity)
+        [ "$PLATFORM" = "bungee" ] || JVM_FLAGS="$JVM_FLAGS -XX:+UseG1GC \
+-XX:G1HeapRegionSize=4M \
+-XX:+UnlockExperimentalVMOptions \
+-XX:+ParallelRefProcEnabled \
+-XX:+AlwaysPreTouch \
+-DIReallyKnowWhatIAmDoingISwear=true"
+        ;;
+    minecraft|bukkit|craftbukkit|spigot|paper)
+        JVM_FLAGS="$JVM_FLAGS -Dcom.mojang.eula.agree=true \
+-DIReallyKnowWhatIAmDoingISwear=true"
+        [ "$PLATFORM" = "paper" ] && JVM_FLAGS="$JVM_FLAGS -XX:+UseG1GC \
+-XX:+ParallelRefProcEnabled \
+-XX:MaxGCPauseMillis=200 \
+-XX:+UnlockExperimentalVMOptions \
+-XX:+DisableExplicitGC \
+-XX:+AlwaysPreTouch \
+-XX:G1NewSizePercent=30 \
+-XX:G1MaxNewSizePercent=40 \
+-XX:G1HeapRegionSize=8M \
+-XX:G1ReservePercent=20 \
+-XX:G1HeapWastePercent=5 \
+-XX:G1MixedGCCountTarget=4 \
+-XX:InitiatingHeapOccupancyPercent=15 \
+-XX:G1MixedGCLiveThresholdPercent=90 \
+-XX:G1RSetUpdatingPauseTimePercent=5 \
+-XX:SurvivorRatio=32 \
+-XX:+PerfDisableSharedMem \
+-XX:MaxTenuringThreshold=1 \
+-Dusing.aikars.flags=https://mcflags.emc.gs \
+-Daikars.new.flags=true"
+        ;;
+    custom)
+        ;;
+    *)
+        echo "$EXEC_NAME: invalid platform: $PLATFORM. Valid: \
+bungee, waterfall, velocity, minecraft, bukkit, craftbukkit, spigot, paper, custom" >&2
+        exit 2
+        ;;
+esac
+
+[ -n "$JAVA_HOME" ] && [ -d "$JAVA_HOME/bin" ] && PATH="$JAVA_HOME/bin:$PATH"
+
+java -version > /dev/null 2>&1 || {
+    echo "$EXEC_NAME: unable to get Java version (is Java installed?)" >&2
+    exit 2
+}
+
+[ -n "$MAX_MEMORY" ] && JVM_FLAGS="-Xmx$MAX_MEMORY $JVM_FLAGS"
+[ -n "$MIN_MEMORY" ] && JVM_FLAGS="-Xms$MIN_MEMORY $JVM_FLAGS"
+
+MCA_CMD="$(which java) -server $JVM_FLAGS -jar $MCA_JAR"
+
+# papermc prints uncolored text if the COLORTERM variable is set to `truecolor`
+export COLORTERM=
+
+# we don't quote $MCA_CMD because screen treats arguments after the second one as a command
+# shellcheck disable=SC2086
+exec screen -c "$MCA_SCREENRC_FILE" "-$SCREEN_OPTS"S "$MCA_NAME" -- $MCA_CMD
diff --git a/screenrc b/screenrc
new file mode 100644
index 0000000..4dcdb76
--- /dev/null
+++ b/screenrc
@@ -0,0 +1,44 @@
+termcapinfo xterm* ti@:te@
+
+escape ^Bb
+
+bind c
+bind ^c
+bind :
+bind ^:
+bind |
+bind s
+bind \"
+bind -
+bind i
+bind ^i
+bind o
+bind ^o
+bind f
+bind ^f
+bind x
+bind ^x
+bind h
+bind ^h
+bind g
+bind ^g
+bind r
+bind ^r
+bind t
+bind ^t
+bind p
+bind ^p
+bind n
+bind ^n
+bind v
+bind .
+bind ^.
+bind ,
+bind ^,
+bind >
+bind ^>
+bind <
+bind ^<
+bind \'
+
+bindkey ^c echo 'The CTRL+C keyboard shortcut has been disabled to prevent accidental process termination'