classes: rootfs-postcommands: autologin root on serial-getty

when empty-root-password AND serial-autologin-root are part of the
IMAGE_FEATURES, save some of the developers time by not having to type
the (then still sole) 'root' username on the serial console after each
and every reboot

this is done by inserting '--autologin root' into the command line of
the responsible 'getty' service

(From OE-Core rev: 01b3cb46405f814e27cab5290118211786cd63a0)

Signed-off-by: Johannes Schneider <johannes.schneider@leica-geosystems.com>
Signed-off-by: Luca Ceresoli <luca.ceresoli@bootlin.com>
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>

1 files changed, 20 insertions, 0 deletions

diff --git a/meta/classes-recipe/rootfs-postcommands.bbclass b/meta/classes-recipe/rootfs-postcommands.bbclass
index d40adf5f0e..bf1e992bb2 100644
--- a/meta/classes-recipe/rootfs-postcommands.bbclass
+++ b/meta/classes-recipe/rootfs-postcommands.bbclass
@@ -13,6 +13,9 @@ ROOTFS_POSTPROCESS_COMMAND += '${@bb.utils.contains_any("IMAGE_FEATURES", [ 'deb
 # Allow dropbear/openssh to accept root logins if debug-tweaks or allow-root-login is enabled
 ROOTFS_POSTPROCESS_COMMAND += '${@bb.utils.contains_any("IMAGE_FEATURES", [ 'debug-tweaks', 'allow-root-login' ], "ssh_allow_root_login; ", "",d)}'
 
+# Autologin the root user on the serial console, if empty-root-password and serial-autologin-root are active
+ROOTFS_POSTPROCESS_COMMAND += '${@bb.utils.contains("IMAGE_FEATURES", [ 'empty-root-password', 'serial-autologin-root' ], "serial_autologin_root; ", "",d)}'
+
 # Enable postinst logging if debug-tweaks or post-install-logging is enabled
 ROOTFS_POSTPROCESS_COMMAND += '${@bb.utils.contains_any("IMAGE_FEATURES", [ 'debug-tweaks', 'post-install-logging' ], "postinst_enable_logging; ", "",d)}'
 
@@ -201,6 +204,23 @@ ssh_allow_root_login () {
         fi
 }
 
+#
+# Autologin the 'root' user on the serial terminal,
+# if empty-root-password' AND 'serial-autologin-root are enabled
+#
+serial_autologin_root () {
+        if ${@bb.utils.contains("DISTRO_FEATURES", "sysvinit", "true", "false", d)}; then
+                # add autologin option to util-linux getty only
+                sed -i 's/options="/&--autologin root /' \
+                        "${IMAGE_ROOTFS}${base_bindir}/start_getty"
+        elif ${@bb.utils.contains("DISTRO_FEATURES", "systemd", "true", "false", d)}; then
+                if [ -e ${IMAGE_ROOTFS}${systemd_system_unitdir}/serial-getty@.service ]; then
+                        sed -i '/^\s*ExecStart\b/ s/getty /&--autologin root /' \
+                                "${IMAGE_ROOTFS}${systemd_system_unitdir}/serial-getty@.service"
+                fi
+        fi
+}
+
 python sort_passwd () {
     import rootfspostcommands
     rootfspostcommands.sort_passwd(d.expand('${IMAGE_ROOTFS}${sysconfdir}'))