From 1c4715ade0f203a1cea12d38c558055f4c775ce7 Mon Sep 17 00:00:00 2001
From: masq <root@freepoteries.fr>
Date: Mon, 4 Nov 2024 11:30:01 +0100
Subject: [PATCH] [arch_post_update_update_boot] use variables present in
 profile to set boot path

---
 arch_post_update_update_boot.sh | 60 ++++++++++++++++++++++++++-------
 1 file changed, 47 insertions(+), 13 deletions(-)

diff --git a/arch_post_update_update_boot.sh b/arch_post_update_update_boot.sh
index 5924cbb..014a0b0 100755
--- a/arch_post_update_update_boot.sh
+++ b/arch_post_update_update_boot.sh
@@ -1,30 +1,64 @@
 #!/bin/sh
-set -xe 
-AURA_BIN=/usr/bin/aura
-CURRENT_VERSION=`${AURA_BIN} -Qi linux | sed -n '/^Version *:/p' | grep -o '[^ ]*$'`
-BOOT_BLK=/dev/vg0/boot
+# arch_post_update_update_boot.sh
+#
+# In your /etc/profile, export the following variables
+# LVM_VG_BOOT=vg0
+# LVM_LG_BOOT_NAME=boot
+# BOOT_DIR_SUFFIX=/archlinux
+#
+# Optional variables:
+# PACMAN_BIN=/usr/bin/pacman # Alternative pacman binary (eg: aura)
+# BOOT_SYMLINK=current (in good boot dir)
+
+set -e
+
+source /etc/profile
+
+ask_overwrite() {
+  echo "Existing destination folder ($ARCH_BOOT_DST_CURRENT_VERSION), do you want to overwrite? (y/n)";
+  read OVERWRITE;
+  test "$OVERWRITE" = "y" && return
+  echo "Do not overwrite. Exitting gently..."
+  exit 0;
+}
+
+PACMAN_BIN=${PACMAN_BIN:-/usr/bin/pacman}
+BOOT_SYMLINK=${BOOT_SYMLINK:-current}
+
+CURRENT_VERSION=`${PACMAN_BIN} -Qi linux \
+  | sed -n '/^Version *:/p' \
+  | grep -o '[^ ]*$'`
+BOOT_BLK=/dev/$LVM_VG_BOOT/$LVM_LG_BOOT_NAME
 BOOT_ORIG=/boot
-BOOT_DST=/mnt/boot
-ARCH_BOOT_DST=$BOOT_DST/archlinux
+TMP_BOOT_DST=`mktemp -d`
+
+ARCH_BOOT_DST=$TMP_BOOT_DST/$BOOT_DIR_SUFFIX
 ARCH_BOOT_DST_CURRENT_VERSION=$ARCH_BOOT_DST/$CURRENT_VERSION 
 ARCH_INITRAMFS=initramfs-linux.img
 ARCH_INITRAMFS_FALLBACK=initramfs-linux-fallback.img
 ARCH_VMLINUZ=vmlinuz-linux
 
-mount $BOOT_BLK $BOOT_DST;
-test -d $ARCH_BOOT_DST_CURRENT_VERSION && echo "Linux version already up to date ($CURRENT_VERSION)" && exit 0;
+mount $BOOT_BLK $TMP_BOOT_DST;
+test -d $ARCH_BOOT_DST_CURRENT_VERSION \
+  && test `realpath $ARCH_BOOT_DST/$BOOT_SYMLINK` = $ARCH_BOOT_DST_CURRENT_VERSION \
+  && echo "Linux version already up to date ($CURRENT_VERSION)" && exit 0;
 
-mkdir $ARCH_BOOT_DST_CURRENT_VERSION;  
+mkdir $ARCH_BOOT_DST_CURRENT_VERSION || ask_overwrite;
 
 (
-cd $BOOT_ORIG;
-cp -t $ARCH_BOOT_DST_CURRENT_VERSION $ARCH_INITRAMFS $ARCH_INITRAMFS_FALLBACK $ARCH_VMLINUZ;
+    cd $BOOT_ORIG;
+    # Copy the new kernel files to the real destination in boot fs
+    cp -t $ARCH_BOOT_DST_CURRENT_VERSION $ARCH_INITRAMFS $ARCH_INITRAMFS_FALLBACK $ARCH_VMLINUZ;
 )
 
 (
-cd $ARCH_BOOT_DST;
-rm current && ln -s $CURRENT_VERSION current;
+    cd $ARCH_BOOT_DST;
+    # Re-link the good version
+    test -f $BOOT_SYMLINK && rm $BOOT_SYMLINK;
+    ln -s $CURRENT_VERSION current;
 )
 
+
 echo "Linux version updated to $CURRENT_VERSION"
+umount $TMP_BOOT_DST;
 exit 0;