Extract kernel version from filename or binary

This is a preperation for initramfs-less booting. This
means that initramfs won't be mandatory anymore, therefore
we can't assume that initramfs will be there for extracting
the kernel version.

Task-number: QTBUG-52758
Change-Id: I397a0fa4925b4ae8a3725921a318542c6132f025
Reviewed-by: Gatis Paeglis <gatis.paeglis@qt.io>

1 files changed, 34 insertions, 19 deletions

diff --git a/qt-ostree/qt-ostree b/qt-ostree/qt-ostree
index defa94e..caeda03 100755
--- a/qt-ostree/qt-ostree
+++ b/qt-ostree/qt-ostree
@@ -290,13 +290,6 @@ validate_arg()
                 validation_error "--gpg-trusted-keyring expects gpg keyring file with the .gpg extension, but ${GPG_TRUSTED_KEYRING} was provided."
             fi
             ;;
-        --initramfs)
-            if [[ "$(basename ${INITRAMFS})" != initramfs-* ]] ; then
-                error="The provided initramfs image ${INITRAMFS} doesn't seem to be generated by the bundled 'generate-initramfs' script."
-                error+=" The required naming pattern is initramfs-\${device}-\${release} or initramfs-\${release}."
-                validation_error "${error}"
-            fi
-            ;;
         --sysroot-image-path)
             INPUT_SYSROOT_ARG_COUNTER=$(( $INPUT_SYSROOT_ARG_COUNTER + 1 ))
             if [ -d "${SYSROOT_IMAGE_PATH}" ] ; then
@@ -527,34 +520,56 @@ path_in_sysroot()
     echo ${target_path}
 }
 
-organize_boot_files()
+get_kernel_info()
 {
-    if [ $(ls ${GENERATED_TREE}/boot/ | wc -l) != 0 ]; then
-        mv -f ${GENERATED_TREE}/boot/* ${BOOT_FILE_PATH}/
-    fi
-
     # Find kernel image.
+    # Note: It might be a good idea to expose KERNEL as command line argument, when
+    # the existing search algorithm is not sufficient.
     cd ${BOOT_FILE_PATH}/
     for boot_file in *; do
         if file -b ${boot_file} | grep -qi "kernel"; then
-            kernel=${BOOT_FILE_PATH}/${boot_file}
-            qt_ostree_info "Found kernel image ${kernel}"
+            KERNEL=${BOOT_FILE_PATH}/${boot_file}
             break
         fi
     done
-    if [ -z "${kernel}" ] ; then
+    if [ -z "${KERNEL}" ] ; then
         qt_ostree_error "Failed to find kernel image in ${BOOT_FILE_PATH}"
     fi
 
+    # Extract kernel version from a file name.
+    KERNEL_VERSION=$(basename "${KERNEL}" | grep -o -E "[1-4]\.[0-9][0-9]*\.[0-9][0-9]*" || true)
+    if [ -z "${KERNEL_VERSION}" ] ; then
+        # Otherwise look for a string in the kernel binary that looks like a kernel version.
+        # Note: This is fragile, it might be a good idea to expose KERNEL_VERSION via command line argument.
+        if file -b "${KERNEL}" | grep -qi "u-boot"; then
+            KERNEL_VERSION=$(strings "${KERNEL}" | grep -o -E "[1-4]\.[0-9][0-9]*\.[0-9][0-9]*" | head -1)
+        else
+            KERNEL_VERSION=$(strings "${KERNEL}" | grep -o -E "^[1-4]\.[0-9][0-9]*\.[0-9][0-9]*" | head -1)
+        fi
+    fi
+    if [ -z "${KERNEL_VERSION}" ] ; then
+        qt_ostree_error "Failed to extract kernel version information from ${KERNEL}".
+    fi
+
+    qt_ostree_info "Using kernel image ${KERNEL} (extracted version: ${KERNEL_VERSION})"
+}
+
+organize_boot_files()
+{
+    if [ $(ls ${GENERATED_TREE}/boot/ | wc -l) != 0 ]; then
+        mv -f ${GENERATED_TREE}/boot/* ${BOOT_FILE_PATH}/
+    fi
+
+    get_kernel_info
+
     # Clean up from unnecessary files and broken symbolic links.
     rm -rf initramfs
     find -L ${BOOT_FILE_PATH}/ -type l -delete
 
     # OSTree deploy requires vmlinuz-*.
-    release=$(basename ${INITRAMFS} | cut -f2- -d'-')
-    bootcsum=$(cat ${kernel} ${INITRAMFS} | sha256sum | cut -f 1 -d ' ')
-    mv ${kernel} ${BOOT_FILE_PATH}/vmlinuz-${release}-${bootcsum}
-    cp ${INITRAMFS} ${BOOT_FILE_PATH}/initramfs-${release}-${bootcsum}
+    bootcsum=$(cat ${KERNEL} ${INITRAMFS} | sha256sum | cut -f 1 -d ' ')
+    mv ${KERNEL} ${BOOT_FILE_PATH}/vmlinuz-${KERNEL_VERSION}-${bootcsum}
+    cp ${INITRAMFS} ${BOOT_FILE_PATH}/initramfs-${KERNEL_VERSION}-${bootcsum}
 
     # Boot loader companions.
     if [[ "${BOOTLOADER}" = "u-boot" && -n "${UBOOT_ENV_FILE}" ]] ; then