2. Install ctags dependencies

sudo apt install autoconf automake

3. Clone the universal-ctags repository

git clone https://github.com/universal-ctags/ctags.git

4. Compile and install ctags

cd ctags
./autogen.sh
./configure
make
sudo make install

Note: If the installation fails, you can copy the binary version of ctags to /usr/local/bin. 5. Download and extract the latest Tomcat core

tar -xvf apache-tomcat-9.0.53.tar.gz

6. Start Tomcat (use shutdown.sh to stop it)

sh apache-tomcat-9.0.53/bin/startup.sh

7. Open your browser and go to http://localhost:8080 8. Download and extract the latest OpenGrok release from GitHub

tar -xvf opengrok-1.3.16.tar.gz

9. Copy the source.war file to the Tomcat webapps directory

cp opengrok-1.3.16/lib/source.war apache-tomcat-9.0.53/webapps/

10. Set up environment variables

sudo vi ~/.bashrc
# Add the following lines
export JAVA_HOME=/usr
export OPENGROK_TOMCAT_BASE=/home/user/app/opengrok/apache-tomcat-9.0.53
export CATALINA_HOME=/home/user/app/opengrok/apache-tomcat-9.0.53
export OPENGROK_APP_SERVER=Tomcat
export OPENGROK_INSTANCE_BASE=/home/user/app/opengrok/opengrok-1.3.16
export LANG=zh_CN.UTF-8

11. Aply the environment variables

source ~/.bashrc

12. Create necessary directories

mkdir -p opengrok-1.3.16/{etc,src,data,history}

13. Copy or link your source code to the src directory

cp -r /path/to/your/code opengrok-1.3.16/src/  # or ln -s /path/to/your/code opengrok-1.3.16/src/your_code

14. Gneerate the index (re-run this command after any updates in the src directory)

java -jar opengrok-1.3.16/lib/opengrok.jar -P -S -v -s opengrok-1.3.16/src -d opengrok-1.3.16/data -H --repository opengrok-1.3.16/history -W opengrok-1.3.16/etc/configuration.xml

15. Modify the actual configuration path in web.xml

gedit apache-tomcat-9.0.53/webapps/source/WEB-INF/web.xml
<context-param>
    <description>Full path to the configuration file where OpenGrok can read its configuration</description>
    <param-name>CONFIGURATION</param-name>
    <param-value>/home/user/app/opengrok/opengrok-1.3.16/etc/configuration.xml</param-value>
</context-param>

16. Open the website at http://localhost:8085/source/ 17. If there is a port conflict, modify the ports in server.xml

sudo cat conf/server.xml
<Server port="8006" shutdown="SHUTDOWN">

<Connector port="8085" protocol="HTTP/1.1"
               connectionTimeout="20000"
               redirectPort="8443"
               address="127.0.0.1" />

<Connector protocol="AJP/1.3"
               address="::1"
               port="8010"
               redirectPort="8443" />

18. Restart Tomcat and open the webpage

sh apache-tomcat-9.0.53/bin/shutdown.sh && sh apache-tomcat-9.0.53/bin/startup.sh