systemd: move activation script to separate file

This makes the following commit more readable.

modules/systemd-activate.nix

@@ -0,0 +1,112 @@
+systemctlPath:
+''
+function isStartable() {
+  local service="$1"
+  [[ $(${systemctlPath} --user show -p RefuseManualStart "$service") == *=no ]]
+}
+
+function isStoppable() {
+  if [[ -v oldGenPath ]] ; then
+    local service="$1"
+    [[ $(${systemctlPath} --user show -p RefuseManualStop "$service") == *=no ]]
+  fi
+}
+
+function systemdPostReload() {
+  local workDir
+  workDir="$(mktemp -d)"
+
+  if [[ -v oldGenPath ]] ; then
+    local oldUserServicePath="$oldGenPath/home-files/.config/systemd/user"
+  fi
+
+  local newUserServicePath="$newGenPath/home-files/.config/systemd/user"
+  local oldServiceFiles="$workDir/old-files"
+  local newServiceFiles="$workDir/new-files"
+  local servicesDiffFile="$workDir/diff-files"
+
+  if [[ ! (-v oldUserServicePath && -d "$oldUserServicePath") \
+      && ! -d "$newUserServicePath" ]]; then
+    return
+  fi
+
+  if [[ ! (-v oldUserServicePath && -d "$oldUserServicePath") ]]; then
+    touch "$oldServiceFiles"
+  else
+    find "$oldUserServicePath" \
+      -maxdepth 1 -name '*.service' -exec basename '{}' ';' \
+      | sort \
+      > "$oldServiceFiles"
+  fi
+
+  if [[ ! -d "$newUserServicePath" ]]; then
+    touch "$newServiceFiles"
+  else
+    find "$newUserServicePath" \
+      -maxdepth 1 -name '*.service' -exec basename '{}' ';' \
+      | sort \
+      > "$newServiceFiles"
+  fi
+
+  diff \
+    --new-line-format='+%L' \
+    --old-line-format='-%L' \
+    --unchanged-line-format=' %L' \
+    "$oldServiceFiles" "$newServiceFiles" \
+    > $servicesDiffFile || true
+
+  local -a maybeRestart=( $(grep '^ ' $servicesDiffFile | cut -c2-) )
+  local -a maybeStop=( $(grep '^-' $servicesDiffFile | cut -c2-) )
+  local -a maybeStart=( $(grep '^+' $servicesDiffFile | cut -c2-) )
+  local -a toRestart=( )
+  local -a toStop=( )
+  local -a toStart=( )
+
+  for f in ''${maybeRestart[@]} ; do
+    if isStoppable "$f" \
+        && isStartable "$f" \
+        && ${systemctlPath} --quiet --user is-active "$f" \
+        && ! cmp --quiet \
+            "$oldUserServicePath/$f" \
+            "$newUserServicePath/$f" ; then
+      toRestart+=("$f")
+    fi
+  done
+
+  for f in ''${maybeStop[@]} ; do
+    if isStoppable "$f" ; then
+      toStop+=("$f")
+    fi
+  done
+
+  for f in ''${maybeStart[@]} ; do
+    if isStartable "$f" ; then
+      toStart+=("$f")
+    fi
+  done
+
+  rm -r $workDir
+
+  local sugg=""
+
+  if [[ -n "''${toRestart[@]}" ]] ; then
+    sugg="''${sugg}systemctl --user restart ''${toRestart[@]}\n"
+  fi
+
+  if [[ -n "''${toStop[@]}" ]] ; then
+    sugg="''${sugg}systemctl --user stop ''${toStop[@]}\n"
+  fi
+
+  if [[ -n "''${toStart[@]}" ]] ; then
+    sugg="''${sugg}systemctl --user start ''${toStart[@]}\n"
+  fi
+
+  if [[ -n "$sugg" ]] ; then
+    echo "Suggested commands:"
+    echo -n -e "$sugg"
+  fi
+}
+
+$DRY_RUN_CMD ${systemctlPath} --user daemon-reload
+systemdPostReload
+''

modules/systemd.nix

@@ -118,117 +118,8 @@ in
           (buildServices "timer" cfg.timers)
         );
 
-      home.activation.reloadSystemD = dagEntryAfter ["linkGeneration"] ''
-        function isStartable() {
-          local service="$1"
-          [[ $(${cfg.systemctlPath} --user show -p RefuseManualStart "$service") == *=no ]]
-        }
-
-        function isStoppable() {
-          if [[ -v oldGenPath ]] ; then
-            local service="$1"
-            [[ $(${cfg.systemctlPath} --user show -p RefuseManualStop "$service") == *=no ]]
-          fi
-        }
-
-        function systemdPostReload() {
-          local workDir
-          workDir="$(mktemp -d)"
-
-          if [[ -v oldGenPath ]] ; then
-            local oldUserServicePath="$oldGenPath/home-files/.config/systemd/user"
-          fi
-
-          local newUserServicePath="$newGenPath/home-files/.config/systemd/user"
-          local oldServiceFiles="$workDir/old-files"
-          local newServiceFiles="$workDir/new-files"
-          local servicesDiffFile="$workDir/diff-files"
-
-          if [[ ! (-v oldUserServicePath && -d "$oldUserServicePath") \
-              && ! -d "$newUserServicePath" ]]; then
-            return
-          fi
-
-          if [[ ! (-v oldUserServicePath && -d "$oldUserServicePath") ]]; then
-            touch "$oldServiceFiles"
-          else
-            find "$oldUserServicePath" \
-              -maxdepth 1 -name '*.service' -exec basename '{}' ';' \
-              | sort \
-              > "$oldServiceFiles"
-          fi
-
-          if [[ ! -d "$newUserServicePath" ]]; then
-            touch "$newServiceFiles"
-          else
-            find "$newUserServicePath" \
-              -maxdepth 1 -name '*.service' -exec basename '{}' ';' \
-              | sort \
-              > "$newServiceFiles"
-          fi
-
-          diff \
-            --new-line-format='+%L' \
-            --old-line-format='-%L' \
-            --unchanged-line-format=' %L' \
-            "$oldServiceFiles" "$newServiceFiles" \
-            > $servicesDiffFile || true
-
-          local -a maybeRestart=( $(grep '^ ' $servicesDiffFile | cut -c2-) )
-          local -a maybeStop=( $(grep '^-' $servicesDiffFile | cut -c2-) )
-          local -a maybeStart=( $(grep '^+' $servicesDiffFile | cut -c2-) )
-          local -a toRestart=( )
-          local -a toStop=( )
-          local -a toStart=( )
-
-          for f in ''${maybeRestart[@]} ; do
-            if isStoppable "$f" \
-                && isStartable "$f" \
-                && ${cfg.systemctlPath} --quiet --user is-active "$f" \
-                && ! cmp --quiet \
-                    "$oldUserServicePath/$f" \
-                    "$newUserServicePath/$f" ; then
-              toRestart+=("$f")
-            fi
-          done
-
-          for f in ''${maybeStop[@]} ; do
-            if isStoppable "$f" ; then
-              toStop+=("$f")
-            fi
-          done
-
-          for f in ''${maybeStart[@]} ; do
-            if isStartable "$f" ; then
-              toStart+=("$f")
-            fi
-          done
-
-          rm -r $workDir
-
-          local sugg=""
-
-          if [[ -n "''${toRestart[@]}" ]] ; then
-            sugg="''${sugg}systemctl --user restart ''${toRestart[@]}\n"
-          fi
-
-          if [[ -n "''${toStop[@]}" ]] ; then
-            sugg="''${sugg}systemctl --user stop ''${toStop[@]}\n"
-          fi
-
-          if [[ -n "''${toStart[@]}" ]] ; then
-            sugg="''${sugg}systemctl --user start ''${toStart[@]}\n"
-          fi
-
-          if [[ -n "$sugg" ]] ; then
-            echo "Suggested commands:"
-            echo -n -e "$sugg"
-          fi
-        }
-
-        $DRY_RUN_CMD ${cfg.systemctlPath} --user daemon-reload
-        systemdPostReload
-      '';
+      home.activation.reloadSystemD = dagEntryAfter ["linkGeneration"]
+        (import ./systemd-activate.nix cfg.systemctlPath);
     })
   ];
 }