grub-config: new script

opt/grub-config

@@ -0,0 +1,102 @@
+#!/usr/bin/env bash
+
+OS_NAME="Void Linux USB"
+GRUB_PREFIX="/boot/efi/LOADER/grub"
+CFG_CUSTOM_BEFORE="custom_before.cfg"
+CFG_CUSTOM_AFTER="custom_after.cfg"
+LINUX_CMDLINE=""
+
+DEFAULT_LINUX=/boot/vmlinu?
+if [ ! -f "$DEFAULT_LINUX" ]; then
+  # in cases where it’s a .gz or .xz or whatever
+  DEFAULT_LINUX=$(find /boot -type l -name "vmlinu*" 2>/dev/null | sort | head -n1)
+fi
+
+DEFAULT_INITRAMFS=/boot/initramfs.img
+if [ ! -f "$DEFAULT_INITRAMFS" ]; then
+  # hope to find anything named initramfs or initrd
+  DEFAULT_INITRAMFS=$(find /boot -type l -name "init*" 2>/dev/null | sort | head -n1)
+fi
+
+function make_menuentry {
+  # $1 is the kernel path
+
+  # We don’t want duplicate entries for /boot/vmlinuz symlink
+  if [ -L $1 ]; then
+    return 0
+  fi
+
+  # exclude garbage globbing results
+  if [ ! -f $1 ]; then
+    return 0
+  fi
+
+  LINUX="$(basename "$1")"
+  LINUX_VERSION="$(sed 's/^kernel//;s/^vm//;s/^linuz//;s/^linux//;s/^-//' <<< "$LINUX")"
+  if grep -e ".gz$" -e ".xz$" -e ".bz$" -e ".bz2$" -e ".lzma$" -e ".lz$" -e ".img$" >/dev/null 2>&1 <<< "$LINUX"; then
+    LINUX_VERSION="$(sed 's/[^.]*$//;s/.$//' <<< "$LINUX_VERSION")"
+  fi
+
+  INITRAMFS="$(basename "$(find /boot -name "init*$LINUX_VERSION*" 2>/dev/null | sort | head -n1)")"
+
+  # user output
+  echo "  -> Found $LINUX (version $LINUX_VERSION, initramfs $INITRAMFS)"
+
+  # grub.cfg
+  echo "
+  menuentry 'Linux $LINUX_VERSION' {
+    echo    'Loading $LINUX...'
+    linux   /$LINUX $LINUX_CMDLINE
+    echo    'Loading initial ramdisk...'
+    initrd  /$INITRAMFS
+  }" >> "$GRUB_PREFIX/grub.cfg"
+}
+
+# user output
+echo "Generating grub config..."
+
+# grub.cfg
+echo "# This file is auto-generated by $0.
+# Changes will be overwritten automatically.
+# If you want to add custom entries or other changes, add them to
+# $GRUB_PREFIX/$CFG_CUSTOM_BEFORE or
+# $GRUB_PREFIX/$CFG_CUSTOM_AFTER
+
+search --fs-uuid --set=root $(blkid --output value --match-tag UUID "$(grep " /boot " /proc/mounts | sed -e 's/ .*//')")
+
+set menu_color_normal=white/black
+set menu_color_highlight=black/light-gray
+
+timeout=5
+
+if [ -f  \${config_directory}/$CFG_CUSTOM_BEFORE ]; then
+  source \${config_directory}/$CFG_CUSTOM_BEFORE
+elif [ -z \"\${config_directory}\" -a -f  \$prefix/$CFG_CUSTOM_BEFORE ]; then
+  source \$prefix/$CFG_CUSTOM_BEFORE
+fi
+
+menuentry '$OS_NAME' {
+  echo 'Loading Linux...'
+  linux $DEFAULT_LINUX
+  echo 'Loading initial ramdisk...'
+  initrd $DEFAULT_INITRAMFS
+}
+
+submenu 'Choose kernel version...' {" > "$GRUB_PREFIX/grub.cfg"
+
+for FILE in /boot/{vm,}linu{x,z}* /boot/kernel*; do
+  make_menuentry "$FILE"
+done
+
+# grub.cfg
+echo "
+}
+
+if [ -f  \${config_directory}/$CFG_CUSTOM_AFTER ]; then
+  source \${config_directory}/$CFG_CUSTOM_AFTER
+elif [ -z \"\${config_directory}\" -a -f  \$prefix/$CFG_CUSTOM_AFTER ]; then
+  source \$prefix/$CFG_CUSTOM_AFTER
+fi" >> "$GRUB_PREFIX/grub.cfg"
+
+# user output
+echo "done"