1. Introduction

Starting from VS Code release 1.99, some servers (such as white, black and red who fail the requirements, including glibc >= 2.28 and libstdc++ >= 3.4.25) can not be accessed through VS Code remotely. The official provides a temporary patch to fix this, though an annoying banner is still present.

To make it short, software crosstool-ng can generate a directory sysroot containing library file needed. Then patchelf can help VS Code server consume the required files during the installation process. Finally a script sysroot.sh can tell VS Code and patchelf where to find all those file.

First, I will show users how to set up. Next, I will show what I have done for those who are interested.

2. Usage

For users, what they need to do is just adding those lines to their .bashrc or .cshrc file.

# Patchelf / VS Code
source /home/usr/share/sysroot/sysroot.sh

or

# Patchelf / VS Code
source /home/usr/share/sysroot/sysroot.csh

That's all if you are a user. For developers, the next chapter may be helpful.

3. Configuration

• The main instruction: 修复 远程主机不满足运行VS Code服务器的先决条件
• The repo used: GitHub - ursetto/vscode-sysroot
• Official version: Remote Development FAQ

3.1. Install crosstool-ng

crosstool-NG is a tool to generate required library files sysroot

sudo apt-get update
sudo apt-get install -y gcc g++ gperf bison flex texinfo help2man make libncurses5-dev python3-dev autoconf automake libtool libtool-bin gawk wget bzip2 xz-utils unzip patch rsync meson ninja-build

wget http://crosstool-ng.org/download/crosstool-ng/crosstool-ng-1.26.0.tar.bz2
tar -xjf crosstool-ng-1.26.0.tar.bz2
cd crosstool-ng-1.26.0
./configure --prefix=/home/usr/share/crosstool-ng 
make
make install

3.2. Generate sysroot

sysroot is a directory containing required library files.

sysroot/
├── etc
├── lib
├── lib64 -> lib
├── sbin
├── sysroot.sh
├── usr
└── var

Maybe you shall remove some experiment variables first, such as LD_LIBRARY_PATH, otherwise some unexpected errors.

mkdir toolchain-dir
cd toolchain-dir
# download the config file from https://github.com/ursetto/vscode-sysroot/blob/main/x86_64-gcc-8.5.0-glibc-2.28.config
cp x86_64-gcc-8.5.0-glibc-2.28.config .config
ct-ng build

The directory x86_64-linux-gnu/x86_64-linux-gnu/sysroot is what we needed. For the file .config, what's different from the official version are two variables CT_LINUX_VERSION and CT_GLIBC_MIN_KERNEL. Microsoft set them to 4.19.287, while they shall be 3.10 for Centos 7. For Ubuntu 18.04 with kernel version 4.15.0, 3.10 works.

3.3. Download patchelf

patchelf is a software to help VS Code server to find related library files. The binary file itself works well. I put it into sysroot, following ursetto's instruction. Some steps are necessary due to file permission problems.

cd x86_64-linux-gnu/x86_64-linux-gnu/sysroot/usr
chmod 755 bin
cd bin

# download binary file from https://github.com/NixOS/patchelf/releases/download/0.18.0/patchelf-0.18.0-x86_64.tar.gz
tar -xvf patchelf-0.18.0-x86_64.tar.gz
cp patchelf-0.18.0/bin/patchelf ./

cd ..
chmod -R 555 bin

3.4. Add a source file

This is a script for use's convenience. It defines three variables to help VS Code to find the files. I put the script in sysroot

sysroot.sh

# Path to the dynamic linker in the sysroot (used for --set-interpreter option with patchelf)
export VSCODE_SERVER_CUSTOM_GLIBC_LINKER=/home/usr/share/sysroot/lib/ld-linux-x86-64.so.2
# Path to the library locations in the sysroot (used as --set-rpath option with patchelf)
export VSCODE_SERVER_CUSTOM_GLIBC_PATH=/home/usr/share/sysroot/usr/lib:/home/usr/share/sysroot/lib
# Path to the patchelf binary on the remote host
export VSCODE_SERVER_PATCHELF_PATH=/home/usr/share/sysroot/usr/bin/patchelf

sysroot.csh

# Path to the dynamic linker in the sysroot (used for --set-interpreter option with patchelf)
setenv VSCODE_SERVER_CUSTOM_GLIBC_LINKER /home/usr/share/sysroot/lib/ld-linux-x86-64.so.2
# Path to the library locations in the sysroot (used as --set-rpath option with patchelf)
setenv VSCODE_SERVER_CUSTOM_GLIBC_PATH /home/usr/share/sysroot/usr/lib:/home/usr/share/sysroot/lib
# Path to the patchelf binary on the remote host
setenv VSCODE_SERVER_PATCHELF_PATH /home/usr/share/sysroot/usr/bin/patchelf

cd ../..
chmod 755 sysroot
vi sysroot/sysroot.sh
vi sysroot/sysroot.csh
chmod 555 sysroot

3.5. Something special

Finally, I move sysroot to a public directory.

rsync -avz toolchain-dir/x86_64-linux-gnu/x86_64-linux-gnu/sysroot/ /home/usr/share/sysroot
chown -R xuelab:xue /home/usr/share/sysroot

For users, they need to add those lines to their .bashrc or .cshrc file.

source /home/usr/share/sysroot/sysroot.sh
source /home/usr/share/sysroot/sysroot.csh