1 files changed, 116 insertions, 0 deletions
diff --git a/devtools/platform/nsJSInspector.cpp b/devtools/platform/nsJSInspector.cpp
new file mode 100644
index 0000000000..944cd9d943
--- /dev/null
+++ b/devtools/platform/nsJSInspector.cpp
@@ -0,0 +1,116 @@
+/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2; -*- */
+/* 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/. */
+
+#include "nsJSInspector.h"
+#include "mozilla/HoldDropJSObjects.h"
+#include "mozilla/SpinEventLoopUntil.h"
+#include "mozilla/dom/ScriptSettings.h"
+#include "nsTArray.h"
+
+#define JSINSPECTOR_CONTRACTID "@mozilla.org/jsinspector;1"
+
+#define JSINSPECTOR_CID                              \
+  {                                                  \
+    0xec5aa99c, 0x7abb, 0x4142, {                    \
+      0xac, 0x5f, 0xaa, 0xb2, 0x41, 0x9e, 0x38, 0xe2 \
+    }                                                \
+  }
+
+namespace mozilla {
+namespace jsinspector {
+
+NS_INTERFACE_MAP_BEGIN_CYCLE_COLLECTION(nsJSInspector)
+  NS_INTERFACE_MAP_ENTRY(nsISupports)
+  NS_INTERFACE_MAP_ENTRY(nsIJSInspector)
+NS_INTERFACE_MAP_END
+
+NS_IMPL_CYCLE_COLLECTION_CLASS(nsJSInspector)
+
+NS_IMPL_CYCLE_COLLECTING_ADDREF(nsJSInspector)
+NS_IMPL_CYCLE_COLLECTING_RELEASE(nsJSInspector)
+
+NS_IMPL_CYCLE_COLLECTION_TRAVERSE_BEGIN(nsJSInspector)
+NS_IMPL_CYCLE_COLLECTION_TRAVERSE_END
+
+NS_IMPL_CYCLE_COLLECTION_UNLINK_BEGIN(nsJSInspector)
+  tmp->mRequestors.Clear();
+  tmp->mLastRequestor = JS::NullValue();
+NS_IMPL_CYCLE_COLLECTION_UNLINK_END
+
+NS_IMPL_CYCLE_COLLECTION_TRACE_BEGIN(nsJSInspector)
+  for (uint32_t i = 0; i < tmp->mRequestors.Length(); ++i) {
+    NS_IMPL_CYCLE_COLLECTION_TRACE_JS_MEMBER_CALLBACK(mRequestors[i])
+  }
+  NS_IMPL_CYCLE_COLLECTION_TRACE_JS_MEMBER_CALLBACK(mLastRequestor)
+NS_IMPL_CYCLE_COLLECTION_TRACE_END
+
+nsJSInspector::nsJSInspector()
+    : mNestedLoopLevel(0), mRequestors(1), mLastRequestor(JS::NullValue()) {}
+
+nsJSInspector::~nsJSInspector() {
+  MOZ_ASSERT(mRequestors.Length() == 0);
+  MOZ_ASSERT(mLastRequestor.isNull());
+  mozilla::DropJSObjects(this);
+}
+
+NS_IMETHODIMP
+nsJSInspector::EnterNestedEventLoop(JS::Handle<JS::Value> requestor,
+                                    uint32_t* out) {
+  nsresult rv = NS_OK;
+
+  mLastRequestor = requestor;
+  mRequestors.AppendElement(requestor);
+  mozilla::HoldJSObjects(this);
+
+  mozilla::dom::AutoNoJSAPI nojsapi;
+
+  uint32_t nestLevel = ++mNestedLoopLevel;
+  if (!SpinEventLoopUntil("nsJSInspector::EnterNestedEventLoop"_ns,
+                          [&]() { return mNestedLoopLevel < nestLevel; })) {
+    rv = NS_ERROR_UNEXPECTED;
+  }
+
+  NS_ASSERTION(mNestedLoopLevel <= nestLevel,
+               "nested event didn't unwind properly");
+
+  if (mNestedLoopLevel == nestLevel) {
+    mLastRequestor = mRequestors.ElementAt(--mNestedLoopLevel);
+  }
+
+  *out = mNestedLoopLevel;
+  return rv;
+}
+
+NS_IMETHODIMP
+nsJSInspector::ExitNestedEventLoop(uint32_t* out) {
+  if (mNestedLoopLevel > 0) {
+    mRequestors.RemoveElementAt(--mNestedLoopLevel);
+    if (mNestedLoopLevel > 0)
+      mLastRequestor = mRequestors.ElementAt(mNestedLoopLevel - 1);
+    else
+      mLastRequestor = JS::NullValue();
+  } else {
+    return NS_ERROR_FAILURE;
+  }
+
+  *out = mNestedLoopLevel;
+
+  return NS_OK;
+}
+
+NS_IMETHODIMP
+nsJSInspector::GetEventLoopNestLevel(uint32_t* out) {
+  *out = mNestedLoopLevel;
+  return NS_OK;
+}
+
+NS_IMETHODIMP
+nsJSInspector::GetLastNestRequestor(JS::MutableHandle<JS::Value> out) {
+  out.set(mLastRequestor);
+  return NS_OK;
+}
+
+}  // namespace jsinspector
+}  // namespace mozilla