update.sh: refactoring

1 files changed, 47 insertions, 9 deletions

diff --git a/update.sh b/update.sh
index 597070f..b3bbe05 100755
--- a/update.sh
+++ b/update.sh
@@ -1,10 +1,5 @@
 #!/usr/bin/env bash
 
-# Some utilities (for example, ssh) fix too relaxed file permissions
-# automatically. Others (GHCi is the reason this script exists) just spit out a
-# warning and ignore such files. This script simply removes the write
-# permission for everybody except myself for every file in this repository.
-
 set -o errexit -o nounset -o pipefail
 shopt -s inherit_errexit 2> /dev/null || true
 shopt -s lastpipe
@@ -13,8 +8,51 @@ script_dir="$( dirname -- "${BASH_SOURCE[0]}" )"
 script_dir="$( cd -- "$script_dir" && pwd )"
 readonly script_dir
 
-export PATH="$script_dir/../config-links:$PATH"
+repo_dir=''
+
+cleanup_repo() {
+    if [ -n "$repo_dir" ]; then
+        echo "Cleaning up directory: $repo_dir"
+        rm -rf -- "$repo_dir"
+    fi
+}
+
+config_links_in_path() {
+    # Make sure the links-* utils are available.
+
+    if command -v links-update &> /dev/null; then
+        return 0
+    fi
+
+    # This is a common directory to clone config-links for me.
+    if [ -d "$script_dir/../config-links" ]; then
+        export PATH="$script_dir/../config-links:$PATH"
+        return 0
+    fi
+
+    # If config-links is unavailable, clone it.
+    readonly repo_url=https://github.com/egor-tensin/config-links.git
+    trap cleanup_repo EXIT
+    repo_dir="$( mktemp -d )"
+
+    git clone -q -- "$repo_url" "$repo_dir"
+    export PATH="$repo_dir:$PATH"
+}
+
+links_update() {
+    cd -- "$script_dir"
+    links-update
+
+    # Some utilities (for example, ssh) fix too relaxed file permissions
+    # automatically. Others (GHCi is the reason this exists) just spit out a
+    # warning and ignore such files. This script simply removes the write
+    # permission for everybody except myself for every file in this repository.
+    links-chmod go-w
+}
+
+main() {
+    config_links_in_path
+    links_update
+}
 
-cd -- "$script_dir"
-links-update
-links-chmod go-w
+main