Script fixes

bin/install_tool

@@ -125,8 +125,17 @@ function deb_only {
 function get_latest_github_release_url {
   local repo="$1"
   local glob="$2"
-  curl -s "https://api.github.com/repos/${repo}/releases/latest" | \
-    jq -r --arg rx "${glob}" '.assets[] | select(.name | test($rx)) | .browser_download_url'
+  require jq "jq is required to parse GitHub releases."
+  local response
+  response=$(curl -s "https://api.github.com/repos/${repo}/releases/latest")
+  
+  if ! echo "${response}" | jq -e '.assets' >/dev/null 2>&1; then
+    local msg
+    msg=$(echo "${response}" | jq -r '.message // "Unknown error fetching latest release."')
+    die "GitHub API error for ${repo}: ${msg}"
+  fi
+  
+  echo "${response}" | jq -r --arg rx "${glob}" '.assets[] | select(.name | test($rx)) | .browser_download_url'
 }
 
 function require {

bin/linux/backup.sh

@@ -8,13 +8,18 @@ if [ "$(uname)" != "Linux" ]; then
   exit 1
 fi
 
-DEFAULT=`echo /media/${USER}/[bB]ackup/${USER}/`
+shopt -s nullglob
+matches=( /media/"${USER}"/[bB]ackup/"${USER}"/ )
+shopt -u nullglob
+if [ ${#matches[@]} -gt 0 ]; then
+  DEFAULT="${matches[0]}"
+else
+  DEFAULT="/media/${USER}/Backup/${USER}/"
+fi
 DEST="${1:-${DEFAULT}}"
 
 function verify_dest {
-  arr=($1)
-  items=${#arr[@]}
-  if [ $items -ne 1 ] ; then
+  if [ -z "$1" ] ; then
     echo "Bad count of backup destinations." > /dev/stderr
     exit 1
   fi
@@ -25,7 +30,7 @@ function verify_dest {
     echo -n "Destination $dir does not end in a /, " > /dev/stderr
     echo "this is probably not what you want!" > /dev/stderr
     echo "Press a key to continue, or CTRL-C to cancel." > /dev/stderr
-    read
+    read -r
   fi
 }
 

bin/linux/i3lock.sh

@@ -1,6 +1,10 @@
 #!/bin/sh
 LOCKTIME="${SCREENSAVER_MIN:-5}"
 LOCKER="i3lock -c 000000"
+# Cleanup previously leaked background agents
+pkill -x xss-lock 2>/dev/null || true
+pkill -x xautolock 2>/dev/null || true
+
 # intentionally want word splitting below
 # do not quote this
 /usr/bin/xss-lock -- ${LOCKER} &

bin/linux/switch_virt.sh

@@ -1,11 +1,13 @@
 #!/bin/bash
 
+set -e
+
 if [ $# -lt 1 ] ; then
   echo "Usage: $0 <kvm|vbox>" >&2
   exit 1
 fi
 
-if [ `whoami` != "root" ] ; then
+if [ "$(id -u)" -ne 0 ] ; then
   if which sudo >/dev/null 2>&1 ; then
     sudo "$0" "$@"
     exit