1 files changed, 81 insertions, 0 deletions
diff --git a/devtools/server/actors/heap-snapshot-file.js b/devtools/server/actors/heap-snapshot-file.js
new file mode 100644
index 0000000000..6cac1d0523
--- /dev/null
+++ b/devtools/server/actors/heap-snapshot-file.js
@@ -0,0 +1,81 @@
+/* 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 protocol = require("resource://devtools/shared/protocol.js");
+
+const {
+  heapSnapshotFileSpec,
+} = require("resource://devtools/shared/specs/heap-snapshot-file.js");
+
+loader.lazyRequireGetter(
+  this,
+  "DevToolsUtils",
+  "resource://devtools/shared/DevToolsUtils.js"
+);
+loader.lazyRequireGetter(
+  this,
+  "HeapSnapshotFileUtils",
+  "resource://devtools/shared/heapsnapshot/HeapSnapshotFileUtils.js"
+);
+
+/**
+ * The HeapSnapshotFileActor handles transferring heap snapshot files from the
+ * server to the client. This has to be a global actor in the parent process
+ * because child processes are sandboxed and do not have access to the file
+ * system.
+ */
+exports.HeapSnapshotFileActor = protocol.ActorClassWithSpec(
+  heapSnapshotFileSpec,
+  {
+    initialize(conn, parent) {
+      if (
+        Services.appinfo.processType !== Services.appinfo.PROCESS_TYPE_DEFAULT
+      ) {
+        const err = new Error(
+          "Attempt to create a HeapSnapshotFileActor in a " +
+            "child process! The HeapSnapshotFileActor *MUST* " +
+            "be in the parent process!"
+        );
+        DevToolsUtils.reportException(
+          "HeapSnapshotFileActor.prototype.initialize",
+          err
+        );
+        return;
+      }
+
+      protocol.Actor.prototype.initialize.call(this, conn, parent);
+    },
+
+    /**
+     * @see MemoryFront.prototype.transferHeapSnapshot
+     */
+    async transferHeapSnapshot(snapshotId) {
+      const snapshotFilePath = HeapSnapshotFileUtils.getHeapSnapshotTempFilePath(
+        snapshotId
+      );
+      if (!snapshotFilePath) {
+        throw new Error(`No heap snapshot with id: ${snapshotId}`);
+      }
+
+      const streamPromise = DevToolsUtils.openFileStream(snapshotFilePath);
+
+      const { size } = await IOUtils.stat(snapshotFilePath);
+      const bulkPromise = this.conn.startBulkSend({
+        actor: this.actorID,
+        type: "heap-snapshot",
+        length: size,
+      });
+
+      const [bulk, stream] = await Promise.all([bulkPromise, streamPromise]);
+
+      try {
+        await bulk.copyFrom(stream);
+      } finally {
+        stream.close();
+      }
+    },
+  }
+);