1 files changed, 280 insertions, 0 deletions
diff --git a/ipc/mscom/oop/Handler.cpp b/ipc/mscom/oop/Handler.cpp
new file mode 100644
index 0000000000..ec55370051
--- /dev/null
+++ b/ipc/mscom/oop/Handler.cpp
@@ -0,0 +1,280 @@
+/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* vim: set ts=8 sts=2 et sw=2 tw=80: */
+/* 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 "Handler.h"
+#include "Module.h"
+
+#include "mozilla/ArrayUtils.h"
+#include "mozilla/Assertions.h"
+#include "mozilla/mscom/Objref.h"
+#include "nsWindowsHelpers.h"
+
+#include <objbase.h>
+#include <shlwapi.h>
+#include <string.h>
+
+/* WARNING! The code in this file may be loaded into the address spaces of other
+   processes! It MUST NOT link against xul.dll or other Gecko binaries! Only
+   inline code may be included! */
+
+namespace mozilla {
+namespace mscom {
+
+Handler::Handler(IUnknown* aOuter, HRESULT* aResult)
+    : mRefCnt(0), mOuter(aOuter), mUnmarshal(nullptr), mHasPayload(false) {
+  MOZ_ASSERT(aResult);
+
+  if (!aOuter) {
+    *aResult = E_INVALIDARG;
+    return;
+  }
+
+  StabilizedRefCount<ULONG> stabilizer(mRefCnt);
+
+  *aResult =
+      ::CoGetStdMarshalEx(aOuter, SMEXF_HANDLER, getter_AddRefs(mInnerUnk));
+  if (FAILED(*aResult)) {
+    return;
+  }
+
+  *aResult = mInnerUnk->QueryInterface(IID_IMarshal, (void**)&mUnmarshal);
+  if (FAILED(*aResult)) {
+    return;
+  }
+
+  // mUnmarshal is a weak ref
+  mUnmarshal->Release();
+}
+
+HRESULT
+Handler::InternalQueryInterface(REFIID riid, void** ppv) {
+  if (!ppv) {
+    return E_INVALIDARG;
+  }
+
+  if (riid == IID_IUnknown) {
+    RefPtr<IUnknown> punk(static_cast<IUnknown*>(&mInternalUnknown));
+    punk.forget(ppv);
+    return S_OK;
+  }
+
+  if (riid == IID_IMarshal) {
+    RefPtr<IMarshal> ptr(this);
+    ptr.forget(ppv);
+    return S_OK;
+  }
+
+  // Try the handler implementation
+  HRESULT hr = QueryHandlerInterface(mInnerUnk, riid, ppv);
+  if (hr == S_FALSE) {
+    // The handler knows this interface is not available, so don't bother
+    // asking the proxy.
+    return E_NOINTERFACE;
+  }
+  if (hr != E_NOINTERFACE) {
+    return hr;
+  }
+
+  // Now forward to the marshaler's inner
+  return mInnerUnk->QueryInterface(riid, ppv);
+}
+
+ULONG
+Handler::InternalAddRef() {
+  if (!mRefCnt) {
+    Module::Lock();
+  }
+  return ++mRefCnt;
+}
+
+ULONG
+Handler::InternalRelease() {
+  ULONG newRefCnt = --mRefCnt;
+  if (newRefCnt == 0) {
+    delete this;
+    Module::Unlock();
+  }
+  return newRefCnt;
+}
+
+HRESULT
+Handler::GetUnmarshalClass(REFIID riid, void* pv, DWORD dwDestContext,
+                           void* pvDestContext, DWORD mshlflags, CLSID* pCid) {
+  return mUnmarshal->GetUnmarshalClass(MarshalAs(riid), pv, dwDestContext,
+                                       pvDestContext, mshlflags, pCid);
+}
+
+HRESULT
+Handler::GetMarshalSizeMax(REFIID riid, void* pv, DWORD dwDestContext,
+                           void* pvDestContext, DWORD mshlflags, DWORD* pSize) {
+  if (!pSize) {
+    return E_INVALIDARG;
+  }
+
+  *pSize = 0;
+
+  RefPtr<IUnknown> unkToMarshal;
+  HRESULT hr;
+
+  REFIID marshalAs = MarshalAs(riid);
+  if (marshalAs == riid) {
+    unkToMarshal = static_cast<IUnknown*>(pv);
+  } else {
+    hr = mInnerUnk->QueryInterface(marshalAs, getter_AddRefs(unkToMarshal));
+    if (FAILED(hr)) {
+      return hr;
+    }
+  }
+
+  // We do not necessarily want to use the pv that COM is giving us; we may want
+  // to marshal a different proxy that is more appropriate to what we're
+  // wrapping...
+  hr = mUnmarshal->GetMarshalSizeMax(marshalAs, unkToMarshal.get(),
+                                     dwDestContext, pvDestContext, mshlflags,
+                                     pSize);
+
+#if defined(MOZ_MSCOM_REMARSHAL_NO_HANDLER)
+  return hr;
+#else
+  if (FAILED(hr)) {
+    return hr;
+  }
+
+  if (!HasPayload()) {
+    return S_OK;
+  }
+
+  DWORD payloadSize = 0;
+  hr = GetHandlerPayloadSize(marshalAs, &payloadSize);
+  if (FAILED(hr)) {
+    return hr;
+  }
+
+  *pSize += payloadSize;
+  return S_OK;
+#endif  // defined(MOZ_MSCOM_REMARSHAL_NO_HANDLER)
+}
+
+HRESULT
+Handler::GetMarshalInterface(REFIID aMarshalAsIid, NotNull<IUnknown*> aProxy,
+                             NotNull<IID*> aOutIid,
+                             NotNull<IUnknown**> aOutUnk) {
+  *aOutIid = aMarshalAsIid;
+  return aProxy->QueryInterface(
+      aMarshalAsIid,
+      reinterpret_cast<void**>(static_cast<IUnknown**>(aOutUnk)));
+}
+
+HRESULT
+Handler::MarshalInterface(IStream* pStm, REFIID riid, void* pv,
+                          DWORD dwDestContext, void* pvDestContext,
+                          DWORD mshlflags) {
+  // We do not necessarily want to use the pv that COM is giving us; we may want
+  // to marshal a different proxy that is more appropriate to what we're
+  // wrapping...
+  RefPtr<IUnknown> unkToMarshal;
+  HRESULT hr;
+
+#if defined(MOZ_MSCOM_REMARSHAL_NO_HANDLER)
+  LARGE_INTEGER seekTo;
+  seekTo.QuadPart = 0;
+
+  ULARGE_INTEGER objrefPos;
+
+  // Save the current position as it points to the location where the OBJREF
+  // will be written.
+  hr = pStm->Seek(seekTo, STREAM_SEEK_CUR, &objrefPos);
+  if (FAILED(hr)) {
+    return hr;
+  }
+#endif  // defined(MOZ_MSCOM_REMARSHAL_NO_HANDLER)
+
+  REFIID marshalAs = MarshalAs(riid);
+  IID marshalOutAs;
+
+  hr = GetMarshalInterface(
+      marshalAs, WrapNotNull<IUnknown*>(mInnerUnk), WrapNotNull(&marshalOutAs),
+      WrapNotNull<IUnknown**>(getter_AddRefs(unkToMarshal)));
+  if (FAILED(hr)) {
+    return hr;
+  }
+
+  hr = mUnmarshal->MarshalInterface(pStm, marshalAs, unkToMarshal.get(),
+                                    dwDestContext, pvDestContext, mshlflags);
+  if (FAILED(hr)) {
+    return hr;
+  }
+
+#if defined(MOZ_MSCOM_REMARSHAL_NO_HANDLER)
+  // Obtain the current stream position which is the end of the OBJREF
+  ULARGE_INTEGER endPos;
+  hr = pStm->Seek(seekTo, STREAM_SEEK_CUR, &endPos);
+  if (FAILED(hr)) {
+    return hr;
+  }
+
+  // Now strip out the handler.
+  if (!StripHandlerFromOBJREF(WrapNotNull(pStm), objrefPos.QuadPart,
+                              endPos.QuadPart)) {
+    return E_FAIL;
+  }
+
+  // Fix the IID
+  if (!SetIID(WrapNotNull(pStm), objrefPos.QuadPart, marshalOutAs)) {
+    return E_FAIL;
+  }
+
+  return S_OK;
+#else
+  if (!HasPayload()) {
+    return S_OK;
+  }
+
+  // Unfortunately when COM re-marshals a proxy that prevouisly had a payload,
+  // we must re-serialize it.
+  return WriteHandlerPayload(pStm, marshalAs);
+#endif  // defined(MOZ_MSCOM_REMARSHAL_NO_HANDLER)
+}
+
+HRESULT
+Handler::UnmarshalInterface(IStream* pStm, REFIID riid, void** ppv) {
+  REFIID unmarshalAs = MarshalAs(riid);
+  HRESULT hr = mUnmarshal->UnmarshalInterface(pStm, unmarshalAs, ppv);
+  if (FAILED(hr)) {
+    return hr;
+  }
+
+  // This method may be called on the same object multiple times (as new
+  // interfaces are queried off the proxy). Not all interfaces will necessarily
+  // refresh the payload, so we set mHasPayload using OR to reflect that fact.
+  // (Otherwise mHasPayload could be cleared and the handler would think that
+  // it doesn't have a payload even though it actually does).
+  mHasPayload |= (ReadHandlerPayload(pStm, unmarshalAs) == S_OK);
+
+  return hr;
+}
+
+HRESULT
+Handler::ReleaseMarshalData(IStream* pStm) {
+  return mUnmarshal->ReleaseMarshalData(pStm);
+}
+
+HRESULT
+Handler::DisconnectObject(DWORD dwReserved) {
+  return mUnmarshal->DisconnectObject(dwReserved);
+}
+
+HRESULT
+Handler::Unregister(REFCLSID aClsid) { return Module::Deregister(aClsid); }
+
+HRESULT
+Handler::Register(REFCLSID aClsid) {
+  return Module::Register(aClsid, Module::ThreadingModel::DedicatedUiThreadOnly,
+                          Module::ClassType::InprocHandler);
+}
+
+}  // namespace mscom
+}  // namespace mozilla