Enable agetty service in images based on Alpine

bootstrap/30-fixes.sh

@@ -23,6 +23,12 @@ if is_alpine; then
 
  # Of course, none of the supported single board computers has any cdrom.
  sed -i '/cdrom/d' "${ETC}/fstab"
+
+ # Enable the agetty service, otherwise users won't see a login prompt when
+ # accessing the console of their device through serial ports such as
+ # /dev/ttyS0.
+ create_symlink /etc/init.d/agetty /etc/init.d/agetty.ttyS0
+ chroot_exec rc-update add agetty.ttyS0 default
 fi
 
 

helpers/fs.sh

@@ -80,6 +80,21 @@ create_dir() {
  fi
 }
 
+# Creates a symlink inside the chroot environment.
+# Globals:
+# None
+# Arguments:
+# Target
+# Link name
+# Returns:
+# None
+create_symlink() {
+ local target=$1
+ local link_name=$2
+
+ chroot_exec ln -s "${target}" "${link_name}"
+}
+
 # Creates the temporary directories used while creating an image.
 # Globals:
 # BUILD_DIR