1 files changed, 92 insertions, 0 deletions
diff --git a/nixos/modules/system/boot/loader/init-script/init-script-builder.sh b/nixos/modules/system/boot/loader/init-script/init-script-builder.sh
new file mode 100644
index 00000000000..bd3fc64999d
--- /dev/null
+++ b/nixos/modules/system/boot/loader/init-script/init-script-builder.sh
@@ -0,0 +1,92 @@
+#! @bash@/bin/sh -e
+
+shopt -s nullglob
+
+export PATH=/empty
+for i in @path@; do PATH=$PATH:$i/bin; done
+
+if test $# -ne 1; then
+    echo "Usage: init-script-builder.sh DEFAULT-CONFIG"
+    exit 1
+fi
+
+defaultConfig="$1"
+
+
+[ "$(stat -f -c '%i' /)" = "$(stat -f -c '%i' /boot)" ] || {
+  # see grub-menu-builder.sh
+  echo "WARNING: /boot being on a different filesystem not supported by init-script-builder.sh"
+}
+
+
+
+target="/sbin/init"
+targetOther="/boot/init-other-configurations-contents.txt"
+
+tmp="$target.tmp"
+tmpOther="$targetOther.tmp"
+
+
+configurationCounter=0
+numAlienEntries=`cat <<EOF | egrep '^[[:space:]]*title' | wc -l
+@extraEntries@
+EOF`
+
+
+
+
+# Add an entry to $targetOther
+addEntry() {
+    local name="$1"
+    local path="$2"
+    local shortSuffix="$3"
+
+    configurationCounter=$((configurationCounter + 1))
+
+    local stage2=$path/init
+
+    content="$(
+      echo "#!/bin/sh"
+      echo "# $name"
+      echo "# created by init-script-builder.sh"
+      echo "exec $stage2"
+    )"
+
+    [ "$path" != "$defaultConfig" ] || {
+      echo "$content" > $tmp
+      echo "# older configurations: $targetOther" >> $tmp
+      chmod +x $tmp
+    }
+
+    echo -e "$content\n\n" >> $tmpOther
+}
+
+
+mkdir -p /boot /sbin
+
+addEntry "NixOS - Default" $defaultConfig ""
+
+# Add all generations of the system profile to the menu, in reverse
+# (most recent to least recent) order.
+for link in $((ls -d $defaultConfig/specialisation/* ) | sort -n); do
+    date=$(stat --printf="%y\n" $link | sed 's/\..*//')
+    addEntry "NixOS - variation" $link ""
+done
+
+for generation in $(
+    (cd /nix/var/nix/profiles && ls -d system-*-link) \
+    | sed 's/system-\([0-9]\+\)-link/\1/' \
+    | sort -n -r); do
+    link=/nix/var/nix/profiles/system-$generation-link
+    date=$(stat --printf="%y\n" $link | sed 's/\..*//')
+    if [ -d $link/kernel ]; then
+      kernelVersion=$(cd $(dirname $(readlink -f $link/kernel))/lib/modules && echo *)
+      suffix="($date - $kernelVersion)"
+    else
+      suffix="($date)"
+    fi
+    addEntry "NixOS - Configuration $generation $suffix" $link "$generation ($date)"
+done
+
+mv $tmpOther $targetOther
+mv $tmp $target