From bccffc8bfdfea4c452a5558a27f4d16da9cab6c7 Mon Sep 17 00:00:00 2001
From: Om Kumar <om.kumar@hp.com>
Date: Wed, 12 Mar 2014 12:53:00 +0530
Subject: [PATCH] Refactor code to select boot kernel

The script to find best kernel from image (used by vm
and baremetal element) is duplicated and is not in sync
with each other. Moving the code to img-functions as a
function will reduce duplicated code and make it reusable
in future.

Since img-functions is not accessible in chroot env,
kernel selection is being moved from finalise.d to
cleanup.d in the vm element.

Change-Id: I8fbccc13a2c61a5191ef9ea5d2a8302a3e43b000
---
 bin/disk-image-get-kernel                     | 36 +---------------
 .../cleanup.d/99-extract-kernel-and-ramdisk   | 41 ++-----------------
 elements/vm/cleanup.d/51-bootloader           | 37 +++++++++++++++++
 elements/vm/finalise.d/51-bootloader          | 27 ------------
 lib/img-functions                             | 39 ++++++++++++++++++
 5 files changed, 80 insertions(+), 100 deletions(-)
 create mode 100755 elements/vm/cleanup.d/51-bootloader

diff --git a/bin/disk-image-get-kernel b/bin/disk-image-get-kernel
index 5eb487f7..7fa6785f 100755
--- a/bin/disk-image-get-kernel
+++ b/bin/disk-image-get-kernel
@@ -81,41 +81,7 @@ ensure_nbd
 # sets WORK_DIR
 mount_qcow_image $IMAGE_FILE
 
-# Dig up the initrd and kernel to use.
-BOOTDIR="$WORK_DIR/boot"
-KERNEL=
-RAMDISK=
-if [ -f $WORK_DIR/etc/redhat-release ]; then
-
-    # Prioritize PAE if present
-    KERNEL=$(ls -1rv $BOOTDIR/vmlinuz*  | grep PAE | grep -v debug | head -1)
-    if [ ! $KERNEL ]; then
-        KERNEL=$(ls -1rv $BOOTDIR/vmlinuz* | grep -v debug | head -1)
-        if [ ! $KERNEL ]; then
-            echo "No suitable kernel found."
-            exit 1
-        fi
-    fi
-
-    KERNEL=$(basename $KERNEL)
-    KERNEL_VERSION=`echo $KERNEL | sed 's/vmlinuz-//g'`
-
-    RAMDISK=$(basename `ls $BOOTDIR/initramfs-$KERNEL_VERSION.img`)
-    if [ ! $RAMDISK ]; then
-        echo "Can't find an initramfs for the $KERNEL_VERSION version of the kernel."
-        exit 1
-    fi
-
-elif [ -f $WORK_DIR/etc/debian_version ]; then
-    KERNEL=$(basename `ls -1rv $BOOTDIR/vmlinuz*generic | head -1`)
-    RAMDISK=$(basename `ls -1rv $BOOTDIR/initrd*generic | head -1`)
-elif [ -f $WORK_DIR/etc/SuSE-release ]; then
-    KERNEL=$(basename `ls -1rv $BOOTDIR/vmlinuz`)
-    RAMDISK=$(basename `ls -1rv $BOOTDIR/initrd`)
-else
-    echo "ERROR: Unable to detect operating system"
-    exit 1
-fi
+select_boot_kernel_initrd $WORK_DIR
 
 sudo cp $BOOTDIR/$KERNEL $OUT_DIR/$OUT_PFX-vmlinuz
 sudo cp $BOOTDIR/$RAMDISK $OUT_DIR/$OUT_PFX-initrd
diff --git a/elements/baremetal/cleanup.d/99-extract-kernel-and-ramdisk b/elements/baremetal/cleanup.d/99-extract-kernel-and-ramdisk
index 61f0bf9a..2f3bd5a5 100755
--- a/elements/baremetal/cleanup.d/99-extract-kernel-and-ramdisk
+++ b/elements/baremetal/cleanup.d/99-extract-kernel-and-ramdisk
@@ -19,45 +19,10 @@ set -o pipefail
 
 [ -n "$TARGET_ROOT" ]
 
+source $_LIB/img-functions
+
 # Dig up the initrd and kernel to use.
-BOOTDIR="$TARGET_ROOT/boot"
-KERNEL=
-RAMDISK=
-if [ -n "${DIB_BAREMETAL_KERNEL_PATTERN:-}" -a -n "${DIB_BAREMETAL_INITRD_PATTERN:-}" ]; then
-    KERNEL=$(basename `eval ls -1rv "$BOOTDIR/${DIB_BAREMETAL_KERNEL_PATTERN}" | head -1`)
-    RAMDISK=$(basename `eval ls -1rv "$BOOTDIR/${DIB_BAREMETAL_INITRD_PATTERN}" | head -1`)
-elif [ -f $TARGET_ROOT/etc/redhat-release ]; then
-
-    # Prioritize PAE if present
-    KERNEL=$(ls -1rv $BOOTDIR/vmlinuz*  | grep PAE | grep -v debug | head -1 || echo "")
-    if [ ! $KERNEL ]; then
-        KERNEL=$(ls -1rv $BOOTDIR/vmlinuz* | grep -v debug | head -1 || echo "")
-        if [ ! $KERNEL ]; then
-            echo "No suitable kernel found."
-            exit 1
-        fi
-    fi
-
-    KERNEL=$(basename $KERNEL)
-    KERNEL_VERSION=`echo $KERNEL | sed 's/vmlinuz-//g'`
-
-    RAMDISK=$(basename `ls $BOOTDIR/initramfs-$KERNEL_VERSION.img` || echo "")
-    if [ ! $RAMDISK ]; then
-        echo "Can't find an initramfs for the $KERNEL_VERSION version of the kernel."
-        exit 1
-    fi
-
-elif [ -f $TARGET_ROOT/etc/debian_version ]; then
-    KERNEL=$(basename `ls -1rv $BOOTDIR/vmlinuz*generic | head -1`)
-    RAMDISK=$(basename `ls -1rv $BOOTDIR/initrd*generic | head -1`)
-elif [ -f $TARGET_ROOT/etc/SuSE-release ]; then
-    KERNEL=vmlinuz
-    RAMDISK=initrd
-else
-    echo "ERROR: Unable to detect operating system"
-    exit 1
-fi
-
+select_boot_kernel_initrd $TARGET_ROOT
 sudo cp $BOOTDIR/$KERNEL ${IMAGE_NAME}.vmlinuz
 sudo cp $BOOTDIR/$RAMDISK ${IMAGE_NAME}.initrd
 sudo chmod a+r ${IMAGE_NAME}.vmlinuz
diff --git a/elements/vm/cleanup.d/51-bootloader b/elements/vm/cleanup.d/51-bootloader
new file mode 100755
index 00000000..16514d5c
--- /dev/null
+++ b/elements/vm/cleanup.d/51-bootloader
@@ -0,0 +1,37 @@
+#!/bin/bash
+#
+# Copyright 2014 Hewlett-Packard Development Company, L.P.
+# All Rights Reserved.
+#
+# Licensed under the Apache License, Version 2.0 (the "License"); you may
+# not use this file except in compliance with the License. You may obtain
+# a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
+# WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
+# License for the specific language governing permissions and limitations
+# under the License.
+
+set -eux
+set -o pipefail
+
+[ -n "$TARGET_ROOT" ]
+
+source $_LIB/img-functions
+
+# Dig up the initrd and kernel to use.
+if [ -d $TARGET_ROOT/boot/syslinux ] ; then
+    select_boot_kernel_initrd $TARGET_ROOT
+
+    cat > $TARGET_ROOT/boot/syslinux/syslinux.cfg<<_EOF_
+DEFAULT linux
+
+LABEL linux
+    KERNEL $KERNEL
+    APPEND ro root=LABEL=cloudimg-rootfs console=tty0 console=ttyS0,115200
+    INITRD $RAMDISK
+_EOF_
+fi
diff --git a/elements/vm/finalise.d/51-bootloader b/elements/vm/finalise.d/51-bootloader
index 1938200d..46b40171 100755
--- a/elements/vm/finalise.d/51-bootloader
+++ b/elements/vm/finalise.d/51-bootloader
@@ -29,33 +29,6 @@ function install_extlinux {
 
     mkdir -p /boot/syslinux
     extlinux --install /boot/syslinux
-
-    if [ -f /etc/redhat-release ]; then
-        kernel=$(ls -1rv /boot/vmlinuz* | head -1)
-        initrd=$(ls -1rv /boot/initramfs* | head -1)
-    elif [ -f /etc/SuSE-release ]; then
-        kernel=$(ls -1rv /boot/vmlinuz* | head -1)
-        initrd=$(ls -1rv /boot/initrd* | head -1)
-    elif [ -f /etc/debian_version ]; then
-        kernel=$(ls -1rv /boot/vmlinuz*generic | head -1)
-        initrd=$(ls -1rv /boot/initrd*generic | head -1)
-
-        # in case files with "generic" suffix were not found, fall back to default
-        kernel=${kernel:-$(ls -1rv /boot/vmlinuz* | head -1)}
-        initrd=${initrd:-$(ls -1rv /boot/initrd* | head -1)}
-    else
-        echo "Unable to find kernel and initram"
-        exit 1
-    fi
-
-    cat > /boot/syslinux/syslinux.cfg<<_EOF_
-DEFAULT linux
-
-LABEL linux
-    KERNEL $kernel
-    APPEND ro root=LABEL=cloudimg-rootfs console=tty0 console=ttyS0,115200
-    INITRD  $initrd
-_EOF_
 }
 
 function install_grub2 {
diff --git a/lib/img-functions b/lib/img-functions
index 6db7e1b8..7b17e128 100644
--- a/lib/img-functions
+++ b/lib/img-functions
@@ -127,3 +127,42 @@ function copy_elements_lib () {
   sudo mkdir -p $TMP_MOUNT_PATH/lib/diskimage-builder
   sudo cp -t $TMP_MOUNT_PATH/lib/diskimage-builder $_LIB/elements-functions
 }
+
+# Dig up the initrd and kernel.
+function select_boot_kernel_initrd () {
+    TARGET_ROOT=$1
+    BOOTDIR=$TARGET_ROOT/boot
+    if [ -n "${DIB_BAREMETAL_KERNEL_PATTERN:-}" -a -n "${DIB_BAREMETAL_INITRD_PATTERN:-}" ]; then
+        KERNEL=$(basename `eval ls -1rv "$BOOTDIR/${DIB_BAREMETAL_KERNEL_PATTERN}" | head -1`)
+        RAMDISK=$(basename `eval ls -1rv "$BOOTDIR/${DIB_BAREMETAL_INITRD_PATTERN}" | head -1`)
+    elif [ -f $TARGET_ROOT/etc/redhat-release ]; then
+
+        # Prioritize PAE if present
+        KERNEL=$(ls -1rv $BOOTDIR/vmlinuz* | grep PAE | grep -v debug | head -1 || echo "")
+        KERNEL=${KERNEL:-$(ls -1rv $BOOTDIR/vmlinuz* | grep -v debug | head -1 || echo "")}
+        if [ ! $KERNEL ]; then
+           echo "No suitable kernel found."
+           exit 1
+        fi
+
+        KERNEL=$(basename $KERNEL)
+        KERNEL_VERSION=${KERNEL#vmlinuz-}
+        RAMDISK=$(basename `ls $BOOTDIR/initramfs-$KERNEL_VERSION.img` || echo "")
+        if [ ! $RAMDISK ]; then
+            echo "Can't find an initramfs for the $KERNEL_VERSION version of the kernel."
+            exit 1
+        fi
+    elif [ -f $TARGET_ROOT/etc/debian_version ]; then
+        KERNEL=$(basename `ls -1rv $BOOTDIR/vmlinuz*generic | head -1`)
+        RAMDISK=$(basename `ls -1rv $BOOTDIR/initrd*generic | head -1`)
+        # in case files with "generic" suffix were not found, fall back to default
+        KERNEL=${KERNEL:-$(basename `ls -1rv $BOOTDIR/vmlinuz* | head -1`)}
+        RAMDISK=${RAMDISK:-$(basename `ls -1rv $BOOTDIR/initrd* | head -1`)}
+    elif [ -f $TARGET_ROOT/etc/SuSE-release ]; then
+        KERNEL=vmlinuz
+        RAMDISK=initrd
+    else
+        echo "ERROR: Unable to detect operating system"
+        exit 1
+    fi
+}