Fix: Never assign fallible expressions in local var declarations

- bash treats `local x=$(<expression>)` such that if
  `<expression>` fails, the declaration still succeeds;
- this breaks the intended behavior of `set -e`

Author: struanb

runcvm-scripts/runcvm-ctr-qemu

@@ -25,7 +25,7 @@ error() {
 # Argument e.g. /volume/disk1,/var/lib/docker,ext4,5G
 do_disk() {
   local spec="$1"
-  local src dst fs size
+  local src dst fs size dir UUID
 
   local IFS=','
   read src dst fs size <<< $(echo "$spec")
@@ -53,7 +53,7 @@ do_disk() {
     fi
 
     # Create directory for disk backing file, if needed.
-    local dir="$(busybox dirname "$src")"
+    dir="$(busybox dirname "$src")"
     if ! [ -d "$dir" ]; then
       mkdir -p $(busybox dirname "$src")
     fi
@@ -62,7 +62,7 @@ do_disk() {
     mke2fs -F -t "$fs" "$src" >&2 || error "Error: disk spec '$spec' invalid: mke2fs on '$src' with fs '$fs' failed"
   fi
 
-  local UUID=$(blkid -o value "$src" | head -n 1)
+  UUID=$(blkid -o value "$src" | head -n 1)
   mkdir -p "$RUNCVM_VM_MOUNTPOINT/$dst" >&2
   echo "UUID=$UUID $dst $fs defaults,noatime 0 0" >>/.runcvm/fstab
   DISKS+=(-drive file=$src,format=raw,if=virtio,media=disk,cache=directsync,aio=native)
@@ -252,9 +252,10 @@ ARGS=(
   # Kernel and initrd and kernel cmdline
   -kernel $RUNCVM_KERNEL_PATH
   -initrd $RUNCVM_KERNEL_INITRAMFS_PATH
+  -L $RUNCVM_GUEST/usr/share/qemu
   -append "$RUNCVM_KERNEL_ROOT $INIT rw ${APPEND[*]} $RUNCVM_KERNEL_APPEND"
 )
 
-if [[ "$RUNCVM_BREAK" =~ preqemu ]]; then echo Preparing to run: '$CMD' "${ARGS[@]@Q}"; bash; fi
+if [[ "$RUNCVM_BREAK" =~ preqemu ]]; then echo "Preparing to run: '$CMD' ${ARGS[@]@Q}"; bash; fi
 
 exec "$CMD" "${ARGS[@]}"

runcvm-scripts/runcvm-install-runtime.sh

@@ -48,8 +48,9 @@ docker_restart() {
   # - With systemd, run: systemctl restart docker
   # - On GitHub Codespaces, run: sudo killall dockerd && sudo /usr/local/share/docker-init.sh
 
-  local init=$(ps -o comm,pid 1 | grep ' 1$' | awk '{print $1}')
-  local cmd
+  local cmd init
+  
+  init=$(ps -o comm,pid 1 | grep ' 1$' | awk '{print $1}')
 
   log "  - Preparing to restart dockerd ..."
 

runcvm-scripts/runcvm-runtime

@@ -107,23 +107,29 @@ get_process_env() {
   local file="$1"
   local var="$2"
   local default="$3"
-  local value=$(jq_get "$file" --arg env "$var" '.env[] | select(match("^" + $env + "=")) | match("^" + $env + "=(.*)") | .captures[] | .string')
+  local value
+  
+  value=$(jq_get "$file" --arg env "$var" '.env[] | select(match("^" + $env + "=")) | match("^" + $env + "=(.*)") | .captures[] | .string')
 
   [ -n "$value" ] && echo -n "$value" || echo -n "$default"
 }
 
 get_process_env_boolean() {
   local file="$1"
   local var="$2"
-  local value=$(jq_get "$file" --arg env "$var" '.env[] | select(match("^" + $env + "=")) | match("^" + $env + "=(.*)") | .captures[] | .string')
+  local value
+  
+  value=$(jq_get "$file" --arg env "$var" '.env[] | select(match("^" + $env + "=")) | match("^" + $env + "=(.*)") | .captures[] | .string')
 
   [ -n "$value" ] && echo "1" || echo "0"
 }
 
 get_config_env() {
   local var="$1"
   local default="$2"
-  local value=$(jq_get "$CFG" --arg env "$var" '.process.env[] | select(match("^" + $env + "=")) | match("^" + $env + "=(.*)") | .captures[] | .string')
+  local value
+
+  value=$(jq_get "$CFG" --arg env "$var" '.process.env[] | select(match("^" + $env + "=")) | match("^" + $env + "=(.*)") | .captures[] | .string')
 
   [ -n "$value" ] && echo -n "$value" || echo -n "$default"
 }