1 files changed, 92 insertions, 0 deletions
diff --git a/devtools/shared/fronts/memory.js b/devtools/shared/fronts/memory.js
new file mode 100644
index 000000000..d7a6a3108
--- /dev/null
+++ b/devtools/shared/fronts/memory.js
@@ -0,0 +1,92 @@
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+"use strict";
+
+const { memorySpec } = require("devtools/shared/specs/memory");
+const { Task } = require("devtools/shared/task");
+const protocol = require("devtools/shared/protocol");
+
+loader.lazyRequireGetter(this, "FileUtils",
+                         "resource://gre/modules/FileUtils.jsm", true);
+loader.lazyRequireGetter(this, "HeapSnapshotFileUtils",
+                         "devtools/shared/heapsnapshot/HeapSnapshotFileUtils");
+
+const MemoryFront = protocol.FrontClassWithSpec(memorySpec, {
+  initialize: function (client, form, rootForm = null) {
+    protocol.Front.prototype.initialize.call(this, client, form);
+    this._client = client;
+    this.actorID = form.memoryActor;
+    this.heapSnapshotFileActorID = rootForm
+      ? rootForm.heapSnapshotFileActor
+      : null;
+    this.manage(this);
+  },
+
+  /**
+   * Save a heap snapshot, transfer it from the server to the client if the
+   * server and client do not share a file system, and return the local file
+   * path to the heap snapshot.
+   *
+   * Note that this is safe to call for actors inside sandoxed child processes,
+   * as we jump through the correct IPDL hoops.
+   *
+   * @params Boolean options.forceCopy
+   *         Always force a bulk data copy of the saved heap snapshot, even when
+   *         the server and client share a file system.
+   *
+   * @params {Object|undefined} options.boundaries
+   *         The boundaries for the heap snapshot. See
+   *         ThreadSafeChromeUtils.webidl for more details.
+   *
+   * @returns Promise<String>
+   */
+  saveHeapSnapshot: protocol.custom(Task.async(function* (options = {}) {
+    const snapshotId = yield this._saveHeapSnapshotImpl(options.boundaries);
+
+    if (!options.forceCopy &&
+        (yield HeapSnapshotFileUtils.haveHeapSnapshotTempFile(snapshotId))) {
+      return HeapSnapshotFileUtils.getHeapSnapshotTempFilePath(snapshotId);
+    }
+
+    return yield this.transferHeapSnapshot(snapshotId);
+  }), {
+    impl: "_saveHeapSnapshotImpl"
+  }),
+
+  /**
+   * Given that we have taken a heap snapshot with the given id, transfer the
+   * heap snapshot file to the client. The path to the client's local file is
+   * returned.
+   *
+   * @param {String} snapshotId
+   *
+   * @returns Promise<String>
+   */
+  transferHeapSnapshot: protocol.custom(function (snapshotId) {
+    if (!this.heapSnapshotFileActorID) {
+      throw new Error("MemoryFront initialized without a rootForm");
+    }
+
+    const request = this._client.request({
+      to: this.heapSnapshotFileActorID,
+      type: "transferHeapSnapshot",
+      snapshotId
+    });
+
+    return new Promise((resolve, reject) => {
+      const outFilePath =
+        HeapSnapshotFileUtils.getNewUniqueHeapSnapshotTempFilePath();
+      const outFile = new FileUtils.File(outFilePath);
+
+      const outFileStream = FileUtils.openSafeFileOutputStream(outFile);
+      request.on("bulk-reply", Task.async(function* ({ copyTo }) {
+        yield copyTo(outFileStream);
+        FileUtils.closeSafeFileOutputStream(outFileStream);
+        resolve(outFilePath);
+      }));
+    });
+  })
+});
+
+exports.MemoryFront = MemoryFront;