uninstall: generalize uninstaller script

To prepare for an install-from-source target in the Makefile, create a
general (Unix) 'uninstall.sh' script. This script is nearly identical to
'build/package/pkg/uninstall.sh', with a few notable differences:

1. The script does not run as 'root' by calling itself with 'sudo'; instead,
   operations that may require root privileges are first tried as the
   calling user and, if they fail, are called again with 'sudo'.
2. If the script is run with 'sudo' (or otherwise as 'root'), the user is
   prompted to confirm whether they want to proceed.

These changes help us avoid platform-specific code around finding the
current logged in user to run 'git-bundle-server web-server stop'.

Signed-off-by: Victoria Dye <[email protected]>

Author: vdye

Makefile

@@ -84,7 +84,7 @@ $(PKGDIR)/payload: check-arch build
 	@echo
 	@echo "======== Formatting package contents ========"
 	@build/package/layout-unix.sh --bindir="$(BINDIR)" \
-				      --uninstaller="$(CURDIR)/build/package/pkg/uninstall.sh" \
+				      --uninstaller="$(CURDIR)/scripts/uninstall.sh" \
 				      --output="$(PKGDIR)/payload"
 
 $(PKG_FILENAME): check-version $(PKGDIR)/payload

build/package/pkg/uninstall.sh

@@ -0,0 +1,67 @@
+#!/bin/bash
+set -e
+
+# Setup root escalation operation
+SUDO=$(if command -v sudo >/dev/null 2>&1; then echo sudo; fi)
+retry_root () {
+	$@ 2>/dev/null || "$SUDO" $@
+}
+
+THISDIR="$( cd "$(dirname "$0")" ; pwd -P )"
+PATH_TO_BIN_SYMLINKS="$THISDIR/../bin"
+PATH_TO_MAN_SYMLINKS="$THISDIR/../share/man"
+
+# Ensure we're running as root
+if [ $(id -u) == "0" ]
+then
+	echo
+	echo "WARNING: running this script as root will not remove user-scoped resources such"
+	echo "as daemon configurations."
+	echo
+	read -p "Are you sure you want to proceed? (y/N) " response
+	case $response in
+		[yY]*)
+		break # do nothing
+		;;
+		[nN]*|"")
+		exit 0 # exit
+		;;
+		*)
+		echo "Invalid response: $response"
+		;;
+	esac
+fi
+
+"$THISDIR/bin/git-bundle-server" web-server stop --remove
+
+# Remove symlinks
+for program in "$THISDIR"/bin/*
+do
+    symlink="$PATH_TO_BIN_SYMLINKS/$(basename $program)"
+    if [ -L "$symlink" ]
+    then
+        echo "Deleting '$symlink'..."
+	retry_root rm -f "$symlink"
+    else
+        echo "No symlink found at path '$symlink'."
+    fi
+done
+
+# Remove application files
+if [ -d "$THISDIR" ]
+then
+	echo "Deleting application files in '$THISDIR'..."
+	retry_root rm -rf "$THISDIR"
+else
+	echo "No application files found."
+fi
+
+# If installed via MacOS .pkg, remove package receipt
+PKG_ID=com.github.gitbundleserver
+if command -v pkgutil >/dev/null 2>&1 && pkgutil --pkgs=$PKG_ID >/dev/null 2>&1
+then
+	# Must run as root
+	$SUDO pkgutil --forget $PKG_ID
+fi
+
+exit 0