fix get description when quota enabled (#68)

* Change `EnvironmentFile` to match the new design of the configuration file. (#64)

10-update_grub.conf

@@ -1,2 +0,0 @@
-[Service]
-ExecStartPost=/usr/sbin/grub-mkconfig -o /boot/grub/grub.cfg

41_snapshots-btrfs

@@ -2,68 +2,41 @@
 #
 #
 #########################################################################################################################################################################
-# Written by: Antynea																																					#
+# Written by: Antynea
-# BTC donation address: 1Lbvz244WA8xbpHek9W2Y12cakM6rDe5Rt																												#
+# BTC donation address: 1Lbvz244WA8xbpHek9W2Y12cakM6rDe5Rt
-# Github: https://github.com/Antynea/grub-btrfs 																														#
+# Github: https://github.com/Antynea/grub-btrfs
-#                                                                                                                                                                       #
+#
-# Purpose: Include btrfs snapshots at boot options (grub-menu).																											#
+# Purpose:
-#																																										#
+#   Improves Grub by adding "btrfs snapshots" to the Grub menu.
-# What this script does:																																				#
+#   You can start your system on a "snapshot" from the Grub menu.
-# Simple rollback using snapshots you made previously.																													#
+#   Supports manual snapshots, snapper ...
-# - Automatically List snapshots existing on root partition (btrfs).																									#
+#   Warning : it isn't recommended to start on read-only snapshot
-# - Automatically Detect if "/boot" is in separate partition.																											#
+#
-# - Automatically Detect kernel, initramfs and intel microcode in "/boot" directory on snapshots.                               										#
+# What this script does:
-# - Automatically Create corresponding "menuentry" in grub.cfg , which ensures a very easy rollback.																	#
+# - Automatically List snapshots existing on root partition (btrfs).
-# - Automatically detect snapper and use snapper's snapshot description if available.																					#
+# - Automatically Detect if "/boot" is in separate partition.
-#																																										#
+# - Automatically Detect kernel, initramfs and intel microcode in "/boot" directory on snapshots.
-# How to customize it:																																					#
+# - Automatically Create corresponding "menuentry" in grub.cfg
-# - Add this lines to /etc/default/grub:																																#
+# - Automatically detect snapper and use snapper's snapshot description if available.
-#																																										#
+# - Automatically generate grub.cfg if you use the provided systemd service.
-# * GRUB_BTRFS_SUBMENUNAME="Arch Linux snapshots" 																														#
+#
-#		(Name appearing in the Grub menu.)																																#
+# Installation:
-# * GRUB_BTRFS_PREFIXENTRY="Snapshot:"        		   																													#
+# - Run `make install` or look into Makefile for instructions on where to put each file.
-#		(Add a name ahead your snapshots entries in the Grub menu.) 																									#
+#
-# * GRUB_BTRFS_DISPLAY_PATH_SNAPSHOT="true"																																#
+# Customization:
-#		(Show full path snapshot or only name in the Grub menu)																											#
+#  Refer to config for the list of available options and their default values.
-# * GRUB_BTRFS_TITLE_FORMAT="p/d/n"																																		#
+#  Place your configurations to /etc/default/grub-btrfs/config.
-#		(Custom title, shows/hides p"prefix" d"date" n"name" in the Grub menu, separator "/", custom order available)													#
+#
-# * GRUB_BTRFS_LIMIT="50"																																				#
+# Automatically update Grub
-#		(Limit the number of snapshots populated in the GRUB menu.)																										#
+#  If you would like Grub to automatically update when a snapshots is made or deleted:
-# * GRUB_BTRFS_SUBVOLUME_SORT="descending"																																#
+# - Mount your subvolume which contains snapshots to /.snapshots
-#		(Sort the found subvolumes by newest first ("descending") or oldest first ("ascending").																		#
+# - Use systemctl start/enable grub-btrfs.path
-#		If "ascending" is chosen then the $GRUB_BTRFS_LIMIT oldest subvolumes will populate the menu.)																	#
+#  grub-btrfs.path will automatically (re)generate grub.cfg when a modification appear in /.snapshots
-# * GRUB_BTRFS_SHOW_SNAPSHOTS_FOUND="true"																																#
+#
-#		(Show snapshots found during run "grub-mkconfig")																												#
+# Special thanks for assistance and contributions:
-# * GRUB_BTRFS_SHOW_TOTAL_SNAPSHOTS_FOUND="true"																														#
+# - My friends
-#		(Show Total of snapshots found during run "grub-mkconfig")																										#
+# - All contributors on Github
-# * GRUB_BTRFS_NKERNEL=("vmlinuz-linux") 		 																														#
+#
-#		(Use only if you have custom kernel name.)			                        																					#
-# * GRUB_BTRFS_NINIT=("initramfs-linux.img" "initramfs-linux-fallback.img")																								#
-#		(Use only if you have custom initramfs name.)						                      																		#
-# * GRUB_BTRFS_INTEL_UCODE=("intel-ucode.img") 																															#
-#		(Use only if you have custom intel-ucode.)		    			                          																		#
-# * GRUB_BTRFS_IGNORE_SPECIFIC_PATH=("var/lib/docker")					             																					#
-#		(Ignore specific path during run "grub-mkconfig")																												#
-# * GRUB_BTRFS_SNAPPER_CONFIG="root"																																	#
-#		(Snapper's config name to use)																																	#
-# * GRUB_BTRFS_DISABLE="false"																																			#
-#		Disable Grub-btrfs (default=active)																																#
-#																																										#
-# - Generate grub.cfg (on Arch Linux use grub-mkconfig -o /boot/grub/grub.cfg)																							#
-#																																										#
-# - grub-btrfs automatically generates snapshots entries.																												#
-# - You will see it appear different entries (e.g : Snapshot: [2014-02-12 11:24:37] my snapshot name overkill)															#
-#																																										#
-# Automatically update grub																																				#
-#  If you would like grub to automatically update when Snapper timeline snapshots and cleanups occur, simply install 10-update_grub.conf in the following locations:	#
-# - /etc/systemd/system/snapper-timeline.service.d/																														#
-# - /etc/systemd/system/snapper-cleanup.service.d/																														#
-# Once the configuration files are in place, systemctl daemon-reload should be run to reload the units and make the changes active.										#
-#																																										#
-# Special thanks for assistance and contributions:																														#
-# - My friends																																							#
-# - All contributors on Github																																			#
-#																																										#
 #########################################################################################################################################################################
 
 set -e
@@ -72,13 +45,15 @@ prefix="/usr"
 exec_prefix="/usr"
 datarootdir="/usr/share"
 sysconfdir="/etc"
+grub_btrfs_config="${sysconfdir}/default/grub-btrfs/config"
 
-. "${sysconfdir}/default/grub"
+[[ -f "$grub_btrfs_config" ]] && . "$grub_btrfs_config"
 . "$datarootdir/grub/grub-mkconfig_lib"
+. "${sysconfdir}/default/grub"
 
-######################################
+###################################################
-### Variables in /etc/default/grub ###
+### Variables in /etc/default/grub-btrfs/config ###
-######################################
+###################################################
 ## Disable Grub-btrfs (default=active)
 grub_btrfs_disable=${GRUB_BTRFS_DISABLE:-"false"}
 [[ "${grub_btrfs_disable}" == "true" ]] && exit 0
@@ -110,8 +85,12 @@ show_snap_found=${GRUB_BTRFS_SHOW_SNAPSHOTS_FOUND:-"true"}
 show_total_snap_found=${GRUB_BTRFS_SHOW_TOTAL_SNAPSHOTS_FOUND:-"true"}
 ## Ignore specific path during run "grub-mkconfig"
 ignore_specific_path=("${GRUB_BTRFS_IGNORE_SPECIFIC_PATH[@]}")
-## snapper's config name
+## Snapper's config name
 snapper_config=${GRUB_BTRFS_SNAPPER_CONFIG:-"root"}
+## Override boot partition detection
+override_boot_partition_detection=${GRUB_BTRFS_OVERRIDE_BOOT_PARTITION_DETECTION:-"false"}
+## Customize GRUB directory
+grub_directory=${GRUB_BTRFS_DIRNAME:-"grub"}
 
 ########################
 ### variables script ###
@@ -119,14 +98,20 @@ snapper_config=${GRUB_BTRFS_SNAPPER_CONFIG:-"root"}
 ## Internationalization (default : english)
 export TEXTDOMAIN=grub-btrfs-git
 export TEXTDOMAINDIR="/usr/share/locale"
-## hints string
+## Probe info "Boot partition"
-hs_boot=$(${grub_probe} --target="hints_string" "/boot" 2>/dev/null)
+# Boot device
-## UUID of the boot partition
+boot_device=$(${grub_probe} --target=device /boot)
-boot_uuid=$(${grub_probe} --target="fs_uuid" "/boot" 2>/dev/null)
+# hints string
-## Type filesystem of boot partition
+boot_hs=$(${grub_probe} --device ${boot_device} --target="hints_string" 2>/dev/null)
-boot_fs=$(${grub_probe} --target="fs" "/boot" 2>/dev/null)
+# UUID of the boot partition
-## UUID of the root partition
+boot_uuid=$(${grub_probe} --device ${boot_device} --target="fs_uuid" 2>/dev/null)
-root_uuid=$(${grub_probe} "/" --target="fs_uuid" 2>/dev/null)
+# Type filesystem of boot partition
+boot_fs=$(${grub_probe} --target="fs" /boot 2>/dev/null)
+## Probe info "Root partition"
+# Root device
+root_device=$(${grub_probe} --target=device /)
+# UUID of the root partition
+root_uuid=$(${grub_probe} --device ${root_device} --target="fs_uuid" 2>/dev/null)
 ## Parameters passed to the kernel
 kernel_parameters="$GRUB_CMDLINE_LINUX $GRUB_CMDLINE_LINUX_DEFAULT"
 ## Mount point location
@@ -135,6 +120,16 @@ gbgmp=$(mktemp -d)
 CLASS="--class snapshots --class gnu-linux --class gnu --class os"
 ## save IFS
 oldIFS=$IFS
+## Detect uuid requirement (lvm,btrfs...)
+check_uuid_required() {
+if [ "x${root_uuid}" = "x" ] || [ "x${GRUB_DISABLE_LINUX_UUID}" = "xtrue" ] \
+    || ! test -e "/dev/disk/by-uuid/${root_uuid}" \
+    || ( test -e "${root_device}" && uses_abstraction "${root_device}" lvm ); then
+  LINUX_ROOT_DEVICE=${root_device}
+else
+  LINUX_ROOT_DEVICE=UUID=${root_uuid}
+fi
+}
 
 
 ######################
@@ -164,10 +159,10 @@ test_btrfs()
 
 ## Create entry
 entry()	{
-echo "$@" >> "/boot/grub/grub-btrfs.cfg"
+echo "$@" >> "/boot/$grub_directory/grub-btrfs.cfg"
 # local arg="$@"
-# echo "${arg}" >> "/boot/grub/grub-btrfs.cfg"
+# echo "${arg}" >> "/boot/$grub_directory/grub-btrfs.cfg"
-# cat << EOF >> "/boot/grub/grub-btrfs.cfg"
+# cat << EOF >> "/boot/$grub_directory/grub-btrfs.cfg"
 # ${arg}
 # EOF
 }
@@ -206,13 +201,13 @@ make_menu_entries()
 		set gfxpayload=keep
 		insmod ${boot_fs}
 		if [ x\$feature_platform_search_hint = xy ]; then
-			search --no-floppy --fs-uuid  --set=root ${hs_boot} ${boot_uuid}
+			search --no-floppy --fs-uuid  --set=root ${boot_hs} ${boot_uuid}
 		else
 			search --no-floppy --fs-uuid  --set=root ${boot_uuid}
 		fi
 		echo 'Loading Snapshot: "${snap_date_time}" "${snap_dir_name}"'
 		echo 'Loading Kernel: "${k}" ...'
-		linux \"${boot_dir_root_grub}/"${k}"\" root=UUID=${root_uuid} rw rootflags=subvol=\""${snap_dir_name}"\" ${kernel_parameters}"
+		linux \"${boot_dir_root_grub}/"${k}"\" root="${LINUX_ROOT_DEVICE}" rw rootflags=subvol=\""${snap_dir_name}"\" ${kernel_parameters}"
 				if [[ -f "${boot_dir}"/"${u}" && "${i}" != "${prefix_i}-${kversion}-${alt_suffix_i}" ]] ; then
 					entry "\
 		echo 'Loading Microcode & Initramfs: "${u}" "${i}" ...'
@@ -244,11 +239,11 @@ snapshot_list()
 	# Query info from snapper if it is installed
 	type snapper >/dev/null 2>&1
 	if [[ $? -eq 0 ]]; then
-		local snapper_ids=($(snapper -t 0 -c "$snapper_config" list | tail -n +3 | cut -d'|' -f 2))
+		local snapper_ids=($(snapper -t 0 -c "$snapper_config" list | tail -n +3 | cut -d'|' -f 1))
-		local snapper_types=($(snapper -t 0 -c "$snapper_config" list | tail -n +3 | cut -d'|' -f 1))
+		local snapper_types=($(snapper -t 0 -c "$snapper_config" list | tail -n +3 | cut -d'|' -f 2))
 
 		IFS=$'\n'
-		local snapper_descriptions=($(snapper -t 0 -c "$snapper_config" list | tail -n +3 | cut -d'|' -f 7))
+		local snapper_descriptions=($(snapper -t 0 -c "$snapper_config" list | tail -n +3 | rev | cut -d'|' -f 2 | rev))
 	fi
 
 	IFS=$'\n'
@@ -421,7 +416,7 @@ boot_bounded()
 		snap_dir_name="$(trim "$snap_dir_name")"
 		snap_date_time="$(echo "$item" | cut -d' ' -f1-2)"
 		snap_date_time="$(trim "$snap_date_time")"
-		
+
 		boot_dir="$gbgmp/$snap_dir_name/boot"
 		# Kernel (Original + custom kernel)
 		detect_kernel
@@ -464,12 +459,12 @@ boot_separate()
 	detect_kernel
 	if [ -z "${list_kernel}" ]; then print_error "Kernels not found."; fi
 	name_kernel=("${list_kernel[@]##*"/"}")
-	
+
 	# Initramfs (Original + custom initramfs)
 	detect_initramfs
 	if [ -z "${list_initramfs}" ]; then print_error "Initramfs not found."; fi
 	name_initramfs=("${list_initramfs[@]##*"/"}")
-	
+
 	# microcode (auto-detect + custom microcode)
 	detect_microcode
 	name_microcode=("${list_ucode[@]##*"/"}")
@@ -509,8 +504,8 @@ printf "###### - Grub-btrfs: Snapshot detection started - ######\n" >&2 ;
 # if btrfs prog isn't installed, exit
 test_btrfs
 # Delete existing config
-#rm -f --preserve-root "/boot/grub/grub-btrfs.cfg"
+#rm -f --preserve-root "/boot/$grub_directory/grub-btrfs.cfg"
-> "/boot/grub/grub-btrfs.cfg"
+> "/boot/$grub_directory/grub-btrfs.cfg"
 # Create mount point then mounting
 [[ ! -d $gbgmp ]] && mkdir -p $gbgmp
 mount -o subvolid=5 /dev/disk/by-uuid/$root_uuid $gbgmp/
@@ -518,13 +513,20 @@ mount -o subvolid=5 /dev/disk/by-uuid/$root_uuid $gbgmp/
 count_warning_menuentries=0
 # Count snapshots
 count_limit_snap=0
+# detect uuid requirement
+check_uuid_required
 # Detects if /boot is a separate partition
-if [[ "$root_uuid" != "$boot_uuid" ]]; then
+if [[ "$override_boot_partition_detection" == "true" ]]; then
-	printf "# Info: Separate boot partition detected \n" >&2 ;
+	printf "# Info: Override boot partition detection : enable \n" >&2 ;
 	boot_separate
 	else
-	printf "# Info: Separate boot partition not detected \n" >&2 ;
+	if [[ "$root_uuid" != "$boot_uuid" ]]; then
-	boot_bounded
+		printf "# Info: Separate boot partition detected \n" >&2 ;
+		boot_separate
+		else
+		printf "# Info: Separate boot partition not detected \n" >&2 ;
+		boot_bounded
+	fi
 fi
 # unmounting mount point
 umount $gbgmp
@@ -539,7 +541,7 @@ fi
 if [[ "${count_limit_snap}" = "0" || -z "${count_limit_snap}" ]]; then
 	print_error "No snapshots found."
 fi
-root_grub="$(make_system_path_relative_to_its_root /boot/grub)"
+root_grub="$(make_system_path_relative_to_its_root /boot/$grub_directory)"
 # Make a submenu in GRUB (grub.cfg)
 cat << EOF
 submenu '${submenuname}' {

Makefile

@@ -0,0 +1,14 @@
+PKGNAME ?= grub-btrfs
+PREFIX ?= /usr
+
+SHARE_DIR = $(DESTDIR)$(PREFIX)/share
+LIB_DIR = $(DESTDIR)$(PREFIX)/lib
+
+.PHONY: install
+
+install:
+	@install -Dm755 -t "$(DESTDIR)/etc/grub.d/" 41_snapshots-btrfs
+	@install -Dm644 -t "$(DESTDIR)/etc/default/grub-btrfs/" config
+	@install -Dm644 -t "$(LIB_DIR)/systemd/system/" grub-btrfs.service
+	@install -Dm644 -t "$(LIB_DIR)/systemd/system/" grub-btrfs.path
+	@install -Dm644 -t "$(SHARE_DIR)/licenses/$(PKGNAME)/" LICENSE

README.md

@@ -1,60 +1,60 @@
-[![GitHub release](https://img.shields.io/github/release/Antynea/grub-btrfs.svg)](https://github.com/Antynea/grub-btrfs)
+[![GitHub release](https://img.shields.io/github/release/Antynea/grub-btrfs.svg)](https://github.com/Antynea/grub-btrfs/releases)
-  
+![](https://img.shields.io/github/license/Antynea/grub-btrfs.svg)
+
 ## grub-btrfs
 
-This is a version 3.xx of grub-btrfs
+This is a version 4.xx of grub-btrfs
-##### BTC donation address: 1Lbvz244WA8xbpHek9W2Y12cakM6rDe5Rt
+##### BTC donation address: `1Lbvz244WA8xbpHek9W2Y12cakM6rDe5Rt`
 ##
 ### Description
+Improves Grub by adding "btrfs snapshots" to the Grub menu.
 
-grub-btrfs, Include btrfs snapshots at boot options. (grub menu)
+You can start your system on a "snapshot" from the Grub menu.
+
+Supports manual snapshots, snapper ...
+
+##### Warning : it isn't recommended to start on read-only snapshot
 ##
-### What does grub-btrfs v3.xx do :
+### What does grub-btrfs v4.xx do :
-
-Simple rollback using snapshots you made previously.
-
 * Automatically List snapshots existing on root partition (btrfs).
-
 * Automatically Detect if "/boot" is in separate partition.
-
 * Automatically Detect kernel, initramfs and intel microcode in "/boot" directory on snapshots.
-
+* Automatically Create corresponding "menuentry" in `grub.cfg`
-* Automatically Create corresponding "menuentry" in grub.cfg , which ensures a very easy rollback.
-
 * Automatically detect snapper and use snapper's snapshot description if available.
+* Automatically generate `grub.cfg` if you use the provided systemd service.
 ##
-### How to customize it:
+### Installation :
+#### Arch Linux
 
-You have the possibility to modify many parameters.
+```
-Add this lines to /etc/default/grub:
+pacman -S grub-btrfs
+```
+
+### Manual
+
+* Run `make install` or look into Makefile for instructions on where to put each file.
+
+NOTE: Generate your Grub menu after installation for the changes to take effect. (on Arch Linux use `grub-mkconfig -o /boot/grub/grub.cfg`)
+##
+### Customization:
+
+You have the possibility to modify many parameters in `/etc/default/grub-btrfs/config`.
 
 * GRUB_BTRFS_SUBMENUNAME="Arch Linux Snapshots"
 
-	(Name menu appearing in grub.)
+	(Name appearing in the Grub menu.)
 
 * GRUB_BTRFS_PREFIXENTRY="Snapshot:"
 
-	(Add a name ahead your snapshots entries.)
+	(Add a name ahead your snapshots entries in the Grub menu.)
 	
 * GRUB_BTRFS_DISPLAY_PATH_SNAPSHOT="true"
 	
-	(Show full path snapshot or only name, weird reaction with snapper)
+	(Show full path snapshot or only name in the Grub menu, weird reaction with snapper)
 	
 * GRUB_BTRFS_TITLE_FORMAT="p/d/n"
 
- 	(Custom title, shows/hides p"prefix" d"date" n"name" in grub-menu, separator "/", custom order available)
+ 	(Custom title, shows/hides p"prefix" d"date" n"name" in the Grub menu, separator "/", custom order available)
-
-* GRUB_BTRFS_NKERNEL=("kernel-custom")
-
-	(Use it only if you have a custom kernel name)
-
-* GRUB_BTRFS_NINIT=("initramfs-custom.img" "initrd.img-custom")
-
-	(Use it only if you have a custom initramfs name)
-
-* GRUB_BTRFS_INTEL_UCODE=("intel-ucode.img")
-
-	(Use it only if you have custom intel-ucode)
 
 * GRUB_BTRFS_LIMIT="50"
 
@@ -74,6 +74,18 @@ Add this lines to /etc/default/grub:
 	
 	(Show Total number of snapshots found during run "grub-mkconfig")
 
+* GRUB_BTRFS_NKERNEL=("kernel-custom")
+
+	(Use it only if you have a custom kernel name)
+
+* GRUB_BTRFS_NINIT=("initramfs-custom.img" "initrd.img-custom")
+
+	(Use it only if you have a custom initramfs name)
+
+* GRUB_BTRFS_INTEL_UCODE=("intel-ucode.img")
+
+	(Use it only if you have custom intel-ucode)
+
 * GRUB_BTRFS_IGNORE_SPECIFIC_PATH=("var/lib/docker")
 
 	(Ignore specific path during run "grub-mkconfig")
@@ -82,32 +94,28 @@ Add this lines to /etc/default/grub:
 
 	(Snapper's config name to use)
 
-* GRUB_BTRFS_DISABLE="true"
+* GRUB_BTRFS_DISABLE="false"
 
 	(Disable grub-btrfs)
 
+* GRUB_BTRFS_DIRNAME="grub"
 
-Generate grub.cfg (on Arch linux use grub-mkconfig -o /boot/grub/grub.cfg )
+	(Name of the grub folder in `/boot/`, might be grub2 on some distributions )
 
-grub-btrfs automatically generates snapshots entries.
+* GRUB_BTRFS_OVERRIDE_BOOT_PARTITION_DETECTION="false"
+	(Change to "true" if you have a boot partition in a different subvolume)
 
-You will see it appear differents entries (e.g : Snapshot: 2018-01-03 15:08:41  @test1 )
+* GRUB_BTRFS_MKCONFIG=grub-mkconfig
+
+    (Name or path of the 'grub-mkconfig' executable; might be 'grub2-mkconfig' on some distributions)
 ##
 ### Automatically update grub
-
+If you would like Grub to automatically update when a snapshots is made or deleted:
-If you would like grub to automatically update when Snapper timeline snapshots and cleanups occur, simply install `10-update_grub.conf` in the following locations:
+* Mount your subvolume which contains snapshots to `/.snapshots`
-
+* Use `systemctl start/enable grub-btrfs.path`
-- `/etc/systemd/system/snapper-timeline.service.d/`
+* `grub-btrfs.path` automatically (re)generate `grub.cfg` when a modification appear in `/.snapshots`
-- `/etc/systemd/system/snapper-cleanup.service.d/`
-
-Once the configuration files are in place, `systemctl daemon-reload` should be run to reload the units and make the changes active.
-
-##
-### Discussion
-Pour les francophones : https://forums.archlinux.fr/viewtopic.php?f=18&t=17177
 ##
 ### Special thanks for assistance and contributions
-
 * [maximbaz](https://github.com/maximbaz)
 * [crossroads1112](https://github.com/crossroads1112)
 * [penetal](https://github.com/penetal)

config

@@ -0,0 +1,19 @@
+#!/usr/bin/env bash
+
+# GRUB_BTRFS_SUBMENUNAME="Arch Linux snapshots"                              # Name appearing in the Grub menu
+# GRUB_BTRFS_PREFIXENTRY="Snapshot:"                                         # Add a name ahead your snapshots entries in the Grub menu
+# GRUB_BTRFS_DISPLAY_PATH_SNAPSHOT="true"                                    # Show full path snapshot or only name in the Grub menu
+# GRUB_BTRFS_TITLE_FORMAT="p/d/n"                                            # Custom title, shows/hides p"prefix" d"date" n"name" in the Grub menu, separator "/", custom order available
+# GRUB_BTRFS_LIMIT="50"                                                      # Limit the number of snapshots populated in the GRUB menu
+# GRUB_BTRFS_SUBVOLUME_SORT="descending"                                     # Sort the found subvolumes by newest first ("descending") or oldest first ("ascending") and show $GRUB_BTRFS_LIMIT first entries.
+# GRUB_BTRFS_SHOW_SNAPSHOTS_FOUND="true"                                     # Show snapshots found during run "grub-mkconfig"
+# GRUB_BTRFS_SHOW_TOTAL_SNAPSHOTS_FOUND="true"                               # Show Total of snapshots found during run "grub-mkconfig"
+# GRUB_BTRFS_NKERNEL=("vmlinuz-linux")                                       # Use only if you have custom kernel name
+# GRUB_BTRFS_NINIT=("initramfs-linux.img" "initramfs-linux-fallback.img")    # Use only if you have custom initramfs name
+# GRUB_BTRFS_INTEL_UCODE=("intel-ucode.img")                                 # Use only if you have custom intel-ucode
+# GRUB_BTRFS_IGNORE_SPECIFIC_PATH=("var/lib/docker")                         # Ignore specific path during run "grub-mkconfig"
+# GRUB_BTRFS_SNAPPER_CONFIG="root"                                           # Snapper's config name to use
+# GRUB_BTRFS_DISABLE="false"                                                 # Disable Grub-btrfs
+# GRUB_BTRFS_DIRNAME=grub                                                    # Might be grub2 on some systems ex. /boot/grub2/...
+# GRUB_BTRFS_OVERRIDE_BOOT_PARTITION_DETECTION="false"                       # Change to "true" if you have a boot partition in a different subvolume
+# GRUB_BTRFS_MKCONFIG=grub-mkconfig                                          # Might be 'grub2-mkconfig' on some systems

grub-btrfs.path

@@ -0,0 +1,8 @@
+[Unit]
+Description=Monitors for new snapshots
+
+[Path]
+PathModified=/.snapshots
+
+[Install]
+WantedBy=multi-user.target

grub-btrfs.service

@@ -0,0 +1,11 @@
+[Unit]
+Description=Regenerate grub-btrfs.cfg
+
+[Service]
+Type=oneshot
+# Set the possible paths for `grub-mkconfig`
+Environment="PATH=/sbin:/bin:/usr/sbin:/usr/bin"
+# Load environment variables from the configuration
+EnvironmentFile=/etc/default/grub-btrfs/config
+# Regenerate just '/boot/grub/grub-btrfs.cfg' if it exists and is not empty, else regenerate the whole grub menu
+ExecStart=/bin/bash -c 'if [ -s "/boot/${GRUB_BTRFS_DIRNAME:-grub}/grub-btrfs.cfg" ]; then /etc/grub.d/41_snapshots-btrfs; else ${GRUB_BTRFS_MKCONFIG:-/usr/bin/grub-mkconfig} -o /boot/${GRUB_BTRFS_DIRNAME:-grub}/grub.cfg; fi'