db/update/Editor: add locking method variants

src/db/update/Container.cxx

@@ -118,9 +118,7 @@ UpdateWalk::UpdateContainerFile(Directory &directory,
 	}
 
 	if (tnum == 1) {
-		db_lock();
+		editor.LockDeleteDirectory(contdir);
-		editor.DeleteDirectory(contdir);
-		db_unlock();
 		return false;
 	} else
 		return true;

src/db/update/Editor.cxx

@@ -47,6 +47,14 @@ DatabaseEditor::DeleteSong(Directory &dir, Song *del)
 	db_lock();
 }
 
+void
+DatabaseEditor::LockDeleteSong(Directory &parent, Song *song)
+{
+	db_lock();
+	DeleteSong(parent, song);
+	db_unlock();
+}
+
 /**
  * Recursively remove all sub directories and songs from a directory,
  * leaving an empty directory.
@@ -77,6 +85,14 @@ DatabaseEditor::DeleteDirectory(Directory *directory)
 	directory->Delete();
 }
 
+void
+DatabaseEditor::LockDeleteDirectory(Directory *directory)
+{
+	db_lock();
+	DeleteDirectory(directory);
+	db_unlock();
+}
+
 bool
 DatabaseEditor::DeleteNameIn(Directory &parent, const char *name)
 {

src/db/update/Editor.hxx

@@ -39,6 +39,11 @@ public:
 	 */
 	void DeleteSong(Directory &parent, Song *song);
 
+	/**
+	 * DeleteSong() with automatic locking.
+	 */
+	void LockDeleteSong(Directory &parent, Song *song);
+
 	/**
 	 * Recursively free a directory and all its contents.
 	 *
@@ -46,6 +51,11 @@ public:
 	 */
 	void DeleteDirectory(Directory *directory);
 
+	/**
+	 * DeleteDirectory() with automatic locking.
+	 */
+	void LockDeleteDirectory(Directory *directory);
+
 	/**
 	 * Caller must NOT lock the #db_mutex.
 	 *

src/db/update/UpdateSong.cxx

@@ -42,11 +42,8 @@ UpdateWalk::UpdateSongFile2(Directory &directory,
 		FormatError(update_domain,
 			    "no read permissions on %s/%s",
 			    directory.GetPath(), name);
-		if (song != nullptr) {
+		if (song != nullptr)
-			db_lock();
+			editor.LockDeleteSong(directory, song);
-			editor.DeleteSong(directory, song);
-			db_unlock();
-		}
 
 		return;
 	}
@@ -54,11 +51,8 @@ UpdateWalk::UpdateSongFile2(Directory &directory,
 	if (!(song != nullptr && st->st_mtime == song->mtime &&
 	      !walk_discard) &&
 	    UpdateContainerFile(directory, name, suffix, st)) {
-		if (song != nullptr) {
+		if (song != nullptr)
-			db_lock();
+			editor.LockDeleteSong(directory, song);
-			editor.DeleteSong(directory, song);
-			db_unlock();
-		}
 
 		return;
 	}
@@ -88,9 +82,7 @@ UpdateWalk::UpdateSongFile2(Directory &directory,
 			FormatDebug(update_domain,
 				    "deleting unrecognized file %s/%s",
 				    directory.GetPath(), name);
-			db_lock();
+			editor.LockDeleteSong(directory, song);
-			editor.DeleteSong(directory, song);
-			db_unlock();
 		}
 
 		modified = true;

src/db/update/Walk.cxx

@@ -107,9 +107,7 @@ UpdateWalk::PurgeDeletedFromDirectory(Directory &directory)
 		if (directory_exists(*child))
 			continue;
 
-		db_lock();
+		editor.LockDeleteDirectory(child);
-		editor.DeleteDirectory(child);
-		db_unlock();
 
 		modified = true;
 	}
@@ -118,9 +116,7 @@ UpdateWalk::PurgeDeletedFromDirectory(Directory &directory)
 	directory_for_each_song_safe(song, ns, directory) {
 		const auto path = map_song_fs(*song);
 		if (path.IsNull() || !FileExists(path)) {
-			db_lock();
+			editor.LockDeleteSong(directory, song);
-			editor.DeleteSong(directory, song);
-			db_unlock();
 
 			modified = true;
 		}
@@ -223,11 +219,8 @@ UpdateWalk::UpdateDirectoryChild(Directory &directory,
 
 		assert(&directory == subdir->parent);
 
-		if (!UpdateDirectory(*subdir, st)) {
+		if (!UpdateDirectory(*subdir, st))
-			db_lock();
+			editor.LockDeleteDirectory(subdir);
-			editor.DeleteDirectory(subdir);
-			db_unlock();
-		}
 	} else {
 		FormatDebug(update_domain,
 			    "%s is not a directory, archive or music", name);