Move JavaScript to root lib/ folder

lib/browser/objects-registry.js

@@ -0,0 +1,94 @@
+'use strict';
+
+const v8Util = process.atomBinding('v8_util');
+
+class ObjectsRegistry {
+  constructor() {
+    this.nextId = 0;
+
+    // Stores all objects by ref-counting.
+    // (id) => {object, count}
+    this.storage = {};
+
+    // Stores the IDs of objects referenced by WebContents.
+    // (webContentsId) => [id]
+    this.owners = {};
+  }
+
+  // Register a new object and return its assigned ID. If the object is already
+  // registered then the already assigned ID would be returned.
+  add(webContents, obj) {
+    // Get or assign an ID to the object.
+    let id = this.saveToStorage(obj);
+
+    // Add object to the set of referenced objects.
+    let webContentsId = webContents.getId();
+    let owner = this.owners[webContentsId];
+    if (!owner) {
+      owner = this.owners[webContentsId] = new Set();
+      // Clear the storage when webContents is reloaded/navigated.
+      webContents.once('render-view-deleted', (event, id) => {
+        this.clear(id);
+      });
+    }
+    if (!owner.has(id)) {
+      owner.add(id);
+      // Increase reference count if not referenced before.
+      this.storage[id].count++;
+    }
+    return id;
+  }
+
+  // Get an object according to its ID.
+  get(id) {
+    return this.storage[id].object;
+  }
+
+  // Dereference an object according to its ID.
+  remove(webContentsId, id) {
+    // Dereference from the storage.
+    this.dereference(id);
+
+    // Also remove the reference in owner.
+    this.owners[webContentsId].delete(id);
+  }
+
+  // Clear all references to objects refrenced by the WebContents.
+  clear(webContentsId) {
+    let owner = this.owners[webContentsId];
+    if (!owner)
+      return;
+    for (let id of owner)
+      this.dereference(id);
+    delete this.owners[webContentsId];
+  }
+
+  // Private: Saves the object into storage and assigns an ID for it.
+  saveToStorage(object) {
+    let id = v8Util.getHiddenValue(object, 'atomId');
+    if (!id) {
+      id = ++this.nextId;
+      this.storage[id] = {
+        count: 0,
+        object: object
+      };
+      v8Util.setHiddenValue(object, 'atomId', id);
+    }
+    return id;
+  }
+
+  // Private: Dereference the object from store.
+  dereference(id) {
+    let pointer = this.storage[id];
+    if (pointer == null) {
+      return;
+    }
+    pointer.count -= 1;
+    if (pointer.count === 0) {
+      v8Util.deleteHiddenValue(pointer.object, 'atomId');
+      return delete this.storage[id];
+    }
+  }
+}
+
+module.exports = new ObjectsRegistry;