Ctags generates indices of symbol definitions in source files. It started its life as part of the BSD Unix, but there are several more modern flavors. Zoekt supports both exuberant ctags and universal-ctags.
It is strongly recommended to use Universal Ctags, version
db3d9a6
or newer, running on the Linux platform.
From this version on, universal ctags will be called using seccomp, which guarantees that security problems in ctags cannot escalate to access to the indexing machine.
Ubuntu, Debian and Arch provide universal ctags with seccomp support
compiled in. Zoekt expects the universal-ctags binary to be on
$PATH. Note: only Ubuntu names the binary universal-ctags, while
most distributions name it ctags.
It is possible to install ctags on Ubuntu via apt:
sudo apt install universal-ctags
Use the following invocation to compile and install universal-ctags:
sudo apt-get install
pkg-config autoconf \
libseccomp-dev libseccomp \
libjansson-dev libjansson
./autogen.sh
LDFLAGS=-static ./configure --enable-json --enable-seccomp
make -j4
# create tarball
NAME=ctags-$(date --iso-8601=minutes | tr -d ':' | sed 's|\+.*$||')-$(git show --pretty=format:%h -q)
mkdir ${NAME}
cp ctags ${NAME}/universal-ctags
tar zcf ${NAME}.tar.gz ${NAME}/Zoekt runs ctags with a hard coded list of languages by default.
However, it's possible to pass only the languages available on your system
by wrapping ctags in a script.
- Create a file
custom-ctags.sh:
#!/usr/bin/bash
set -o pipefail
set -eux
CTAGS_LANGUAGES=$(/usr/bin/universal-ctags --list-languages | grep -v 'disabled' | tr '\n' ',' | sed 's/.$//')
/usr/bin/universal-ctags --languages=$CTAGS_LANGUAGES $@- Make it executable:
chmod +x custom-ctags.sh- Set the environment variable when indexing with Zoekt:
export CTAGS_COMMAND=$PWD/custom-ctags.sh
go run cmd/zoekt-index/main.go -index /tmp/zoekt-index /path/to/repository