From 9ad6441b3a9aec9f01c411e1045239fa8988dc98 Mon Sep 17 00:00:00 2001
From: lelgenio <lelgenio@disroot.org>
Date: Wed, 23 Jun 2021 11:59:23 -0300
Subject: [PATCH] root: auto detect root subvolume

---
 config.yaml                         |  4 ++--
 dotfiles/fish/alias.fish            |  2 +-
 dotfiles/scripts/_create-subvolumes | 18 ++++++++++++------
 root/fstab                          | 17 ++++++++++++++---
 root/grub                           |  2 +-
 5 files changed, 30 insertions(+), 13 deletions(-)

diff --git a/config.yaml b/config.yaml
index 49fdf67..c429daf 100644
--- a/config.yaml
+++ b/config.yaml
@@ -43,8 +43,7 @@ variables:
     zram: true
     filesystem:
         partitions:
-            "/": /btrfs
-            "/@root": /
+            "/": /mnt/btrfs-root
             "/@home": /home
             "/@sql": /var/lib/mysql
             "/@swap": /swap
@@ -206,6 +205,7 @@ dynvariables:
     phisical_uuid: sudo blkid /dev/sda2 -s UUID -o value
     decrypted_uuid: sudo blkid /dev/mapper/main -s UUID -o value
     boot_uuid: sudo blkid /dev/sda1 -s UUID -o value
+    root_subvol: echo "/@$(lsb_release -i | cut -f 2)-root"
     nproc: nproc
     memory_size: env LC_ALL=C free -b | awk '/^Mem:/ {print $2}'
     deezer_arl: pass show Entertainment/Deezer | awk '/^arl:/ {print $2}'
diff --git a/dotfiles/fish/alias.fish b/dotfiles/fish/alias.fish
index d55c039..6fecb52 100644
--- a/dotfiles/fish/alias.fish
+++ b/dotfiles/fish/alias.fish
@@ -18,7 +18,7 @@ abbr -g mpn ncmpcpp
 abbr -g dot "dotdrop install -f"
 
 set -l root_cfg (dirname $DOTDROP_CONFIG)/root
-alias rootdrop 'dotdrop install -f -c "$root_cfg"'
+alias rootdrop 'sudo dotdrop install -f -c "$root_cfg"'
 
 cabbr p emerge
 
diff --git a/dotfiles/scripts/_create-subvolumes b/dotfiles/scripts/_create-subvolumes
index 8de4253..2198452 100755
--- a/dotfiles/scripts/_create-subvolumes
+++ b/dotfiles/scripts/_create-subvolumes
@@ -1,12 +1,18 @@
 #!/bin/sh
 
-if ! mountpoint /mnt/btrfs-root
-then
-    mkdir /mnt/btrfs-root
-    mount /mnt/btrfs-root
-fi
-cd /mnt/btrfs-root
+set -e
 
+BTRFS_ROOT="{{@@ filesystem.partitions['/'] @@}}"
+
+if ! mountpoint "$BTRFS_ROOT"
+then
+    mkdir -p "$BTRFS_ROOT"
+    mount "$BTRFS_ROOT"
+fi
+cd "$BTRFS_ROOT"
+
+
+{%@@ set new_partitions = filesystem.partitions.update({root_subvol: '/'}) @@%}
 {%@@ for name, path in filesystem.partitions.items() @@%}
     test -e "./{{@@ name @@}}" ||
         btrfs subvolume create "./{{@@ name @@}}"
diff --git a/root/fstab b/root/fstab
index 75fda70..a750781 100644
--- a/root/fstab
+++ b/root/fstab
@@ -1,12 +1,23 @@
 {{@@ 'non_templated(_dotfile_abs_dst)' | var @@}}
 ##### Dotdrop-start #####
 
+{#@@<filesystem> <dir> <type> <options> <dump> <pass> @@#}
+
+    {%@@ set btrfs_opt_t = "rw,noatime,compress=zstd:3,subvol={}" @@%}
+    {%@@ set entry_t = "UUID={uuid} {path} {fs} {opts} {dump} {pass}" @@%}
+
 UUID={{@@ boot_uuid @@}}    /boot vfat  rw,errors=remount-ro             0 2
 
+{%@@ set new_partitions = filesystem.partitions.update({root_subvol: '/'}) @@%}
 {%@@ for name, path in filesystem.partitions.items() @@%}
-    {#@@<filesystem>  <dir>        <type>  <options>    <dump> <pass> @@#}
-    {%@@ set options = "rw,noatime,compress=zstd:3,subvol={}".format(name) @@%}
-    UUID={{@@ decrypted_uuid @@}} {{@@ path @@}} btrfs   {{@@ options @@}} 0      {{@@ ("root" in name) | int@@}}
+    {{@@ entry_t.format(
+        uuid= decrypted_uuid ,
+        path= path ,
+        fs= "btrfs",
+        opts= btrfs_opt_t.format(name),
+        dump= "0",
+        pass= ("root" in name) | int,
+    ) @@}}
 {%@@ endfor @@%}
 
 /swap/swapfile    none  swap  defaults                         0 0
diff --git a/root/grub b/root/grub
index 10c92b1..a3667bb 100644
--- a/root/grub
+++ b/root/grub
@@ -11,7 +11,7 @@ GRUB_DISTRIBUTOR="Artix"
 
 GRUB_CMDLINE_LINUX_DEFAULT=""
 GRUB_CMDLINE_LINUX=" cryptdevice=UUID={{@@ phisical_uuid @@}}:main "
-GRUB_CMDLINE_LINUX+=" root=/dev/mapper/main rootflags=rw,noatime,compress=zstd,subvol=/@root "
+GRUB_CMDLINE_LINUX+=" root=/dev/mapper/main rootflags=rw,noatime,compress=zstd,subvol=/{{@@ root_subvol @@}} "
 
 # Preload both GPT and MBR modules so that they are not missed
 GRUB_PRELOAD_MODULES="part_gpt part_msdos"