refactor(script): Log steps

README.md

@@ -6,7 +6,7 @@ Arch Linux pacman hook to automatically recreate syslinux and MBR after updates
 
 Get started like so:
 
-1. Install dependency `rsync`
+1. Install dependencies `jq` and `rsync`
 1. Clone repo into arbitrary path `<repo>`
 1. Make `pacman-zbm-syslinux-regen.sh` executable
     ```

pacman-zbm-syslinux-regen.hook

@@ -7,5 +7,6 @@ Target = syslinux
 Description = Regen syslinux and MBR
 When = PostTransaction
 Exec = /usr/local/bin/pacman-zbm-syslinux-regen
+Depends = jq
 Depends = rsync
 AbortOnFail

pacman-zbm-syslinux-regen.sh

@@ -2,20 +2,31 @@
 
 boot_dir='/boot/syslinux'
 boot_dir="${boot_dir%/}"
-boot_disk="$(findmnt --noheadings --target "${boot_dir}" --output 'SOURCE')" || {
+boot_fs="$(findmnt --noheadings --target "${boot_dir}" --output 'SOURCE')" || {
     printf -- '%s\n' \
         'Unable to identify boot drive for '"'${boot_dir}'"' boot dir.' \
         'Cowardly exiting. No syslinux files nor MBR were overwritten.'
     exit 1
 }
-if [[ "$(<<<"${boot_dir}" wc -l)" -gt '1' ]]; then
+if [[ "$(<<<"${boot_fs}" wc -l)" -gt '1' ]]; then
     printf -- '%s\n' \
         'More than one drive mounted at '"'${boot_dir}'"' boot dir.' \
         'Cowardly exiting. No syslinux files nor MBR were overwritten.'
     exit 1
 fi
 
-find "${boot_dir}" -type f -iname '*.c32' -delete
-rsync -a '/usr/lib/syslinux/bios/'*'.c32' "${boot_dir}"'/'
-extlinux --install "${boot_dir}"
-dd bs=440 count=1 conv=notrunc if='/usr/lib/syslinux/bios/mbr.bin' of="${boot_disk}"
+boot_fs_name="$(basename "${boot_fs}")"
+boot_disk="$(lsblk --output 'NAME' --json --tree | jq --raw-output '.[][] | select(.children | length > 0) | select(.children[].name=="'"${boot_fs_name}"'") | .name')"
+if [[ ! "${boot_disk}" ]]; then
+    # There's no parent drive over "${boot_fs}" meaning "${boot_fs}" itself
+    # already is the parent. This is a file system on a drive and not on a
+    # partition.
+    boot_disk="${boot_fs}"
+else
+    boot_disk='/dev/'"${boot_disk}"
+fi
+
+find "${boot_dir}" -type f -iname '*.c32' -delete && echo 'Delete old COMBOOT files from boot drive'
+rsync -a '/usr/lib/syslinux/bios/'*'.c32' "${boot_dir}"'/' && echo 'Put new COMBOOT files onto boot drive'
+extlinux --install "${boot_dir}" &>/dev/null && echo 'Install new extlinux boot loader'
+dd bs=440 count=1 conv=notrunc if='/usr/lib/syslinux/bios/mbr.bin' of="${boot_disk}" 2>/dev/null && echo 'Overwrite MBR with newest version'