From 3339853c26cf5b0f85b3619dac666e38c1d9efcd Mon Sep 17 00:00:00 2001
From: Asher <ash@coder.com>
Date: Fri, 2 Jul 2021 19:19:23 -0500
Subject: [PATCH] Avoid root when prefix is writable

Previously if the prefix was non-existent we would switch to root even
if the user does have the permissions to create the directory.

Fixes #3585
---
 .github/workflows/installer.yml | 18 ++++++++++++++++++
 install.sh                      |  5 ++++-
 2 files changed, 22 insertions(+), 1 deletion(-)

diff --git a/.github/workflows/installer.yml b/.github/workflows/installer.yml
index 0a004b8b5..959397f4f 100644
--- a/.github/workflows/installer.yml
+++ b/.github/workflows/installer.yml
@@ -24,6 +24,24 @@ jobs:
       - name: Test code-server
         run: yarn test:standalone-release code-server
 
+  alpine:
+    name: Test installer on Alpine
+    runs-on: ubuntu-latest
+    container: "alpine:3.14"
+    steps:
+      - name: Checkout repo
+        uses: actions/checkout@v2
+
+      - name: Install curl
+        run: apk add curl
+
+      - name: Add user
+        run: adduser coder --disabled-password
+
+      # Standalone should work without root.
+      - name: Test standalone to a non-existent prefix
+        run: su coder -c "./install.sh --method standalone --prefix /tmp/does/not/yet/exist"
+
   macos:
     name: Test installer on macOS
     runs-on: macos-latest
diff --git a/install.sh b/install.sh
index e51afc191..2b77c5d36 100755
--- a/install.sh
+++ b/install.sh
@@ -132,7 +132,6 @@ main() {
   unset \
     DRY_RUN \
     METHOD \
-    STANDALONE_INSTALL_PREFIX \
     OPTIONAL \
     ALL_FLAGS \
     RSH_ARGS \
@@ -381,6 +380,10 @@ install_standalone() {
   fetch "https://github.com/cdr/code-server/releases/download/v$VERSION/code-server-$VERSION-$OS-$ARCH.tar.gz" \
     "$CACHE_DIR/code-server-$VERSION-$OS-$ARCH.tar.gz"
 
+  # -w only works if the directory exists so try creating it first. If this
+  # fails we can ignore the error as the -w check will then swap us to sudo.
+  sh_c mkdir -p "$STANDALONE_INSTALL_PREFIX" 2> /dev/null || true
+
   sh_c="sh_c"
   if [ ! -w "$STANDALONE_INSTALL_PREFIX" ]; then
     sh_c="sudo_sh_c"