Issue #1829 - Revert "Issue #1751"

netwerk/dns/mdns/libmdns/nsDNSServiceDiscovery.cpp

@@ -0,0 +1,262 @@
+/* -*- 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 "nsDNSServiceDiscovery.h"
+#include "MDNSResponderOperator.h"
+#include "nsICancelable.h"
+#include "nsXULAppAPI.h"
+#include "private/pprio.h"
+
+namespace mozilla {
+namespace net {
+
+namespace {
+
+inline void
+StartService()
+{
+  /*** STUB ***/
+}
+
+inline void
+StopService()
+{
+  /*** STUB ***/
+}
+
+class ServiceCounter
+{
+public:
+  static bool IsServiceRunning()
+  {
+    return !!sUseCount;
+  }
+
+private:
+  static uint32_t sUseCount;
+
+protected:
+  ServiceCounter()
+  {
+    MOZ_ASSERT(NS_IsMainThread());
+    if (!sUseCount++) {
+      StartService();
+    }
+  }
+
+  virtual ~ServiceCounter()
+  {
+    MOZ_ASSERT(NS_IsMainThread());
+    if (!--sUseCount) {
+      StopService();
+    }
+  }
+};
+
+uint32_t ServiceCounter::sUseCount = 0;
+
+class DiscoveryRequest final : public nsICancelable
+                             , private ServiceCounter
+{
+public:
+  NS_DECL_ISUPPORTS
+  NS_DECL_NSICANCELABLE
+
+  explicit DiscoveryRequest(nsDNSServiceDiscovery* aService,
+                            nsIDNSServiceDiscoveryListener* aListener);
+
+private:
+  virtual ~DiscoveryRequest() { Cancel(NS_OK); }
+
+  RefPtr<nsDNSServiceDiscovery> mService;
+  nsIDNSServiceDiscoveryListener* mListener;
+};
+
+NS_IMPL_ISUPPORTS(DiscoveryRequest, nsICancelable)
+
+DiscoveryRequest::DiscoveryRequest(nsDNSServiceDiscovery* aService,
+                                   nsIDNSServiceDiscoveryListener* aListener)
+  : mService(aService)
+  , mListener(aListener)
+{
+}
+
+NS_IMETHODIMP
+DiscoveryRequest::Cancel(nsresult aReason)
+{
+  if (mService) {
+    mService->StopDiscovery(mListener);
+  }
+
+  mService = nullptr;
+  return NS_OK;
+}
+
+class RegisterRequest final : public nsICancelable
+                            , private ServiceCounter
+{
+public:
+  NS_DECL_ISUPPORTS
+  NS_DECL_NSICANCELABLE
+
+  explicit RegisterRequest(nsDNSServiceDiscovery* aService,
+                           nsIDNSRegistrationListener* aListener);
+
+private:
+  virtual ~RegisterRequest() { Cancel(NS_OK); }
+
+  RefPtr<nsDNSServiceDiscovery> mService;
+  nsIDNSRegistrationListener* mListener;
+};
+
+NS_IMPL_ISUPPORTS(RegisterRequest, nsICancelable)
+
+RegisterRequest::RegisterRequest(nsDNSServiceDiscovery* aService,
+                                 nsIDNSRegistrationListener* aListener)
+  : mService(aService)
+  , mListener(aListener)
+{
+}
+
+NS_IMETHODIMP
+RegisterRequest::Cancel(nsresult aReason)
+{
+  if (mService) {
+    mService->UnregisterService(mListener);
+  }
+
+  mService = nullptr;
+  return NS_OK;
+}
+
+} // namespace anonymous
+
+NS_IMPL_ISUPPORTS(nsDNSServiceDiscovery, nsIDNSServiceDiscovery)
+
+nsDNSServiceDiscovery::~nsDNSServiceDiscovery()
+{
+}
+
+nsresult
+nsDNSServiceDiscovery::Init()
+{
+  if (!XRE_IsParentProcess()) {
+    MOZ_ASSERT(false, "nsDNSServiceDiscovery can only be used in parent process");
+    return NS_ERROR_FAILURE;
+  }
+  return NS_OK;
+}
+
+NS_IMETHODIMP
+nsDNSServiceDiscovery::StartDiscovery(const nsACString& aServiceType,
+                                      nsIDNSServiceDiscoveryListener* aListener,
+                                      nsICancelable** aRetVal)
+{
+  MOZ_ASSERT(aRetVal);
+
+  nsresult rv;
+  if (NS_WARN_IF(NS_FAILED(rv = StopDiscovery(aListener)))) {
+    return rv;
+  }
+
+  nsCOMPtr<nsICancelable> req = new DiscoveryRequest(this, aListener);
+  RefPtr<BrowseOperator> browserOp = new BrowseOperator(aServiceType,
+                                                          aListener);
+  if (NS_WARN_IF(NS_FAILED(rv = browserOp->Start()))) {
+    return rv;
+  }
+
+  mDiscoveryMap.Put(aListener, browserOp);
+
+  req.forget(aRetVal);
+
+  return NS_OK;
+}
+
+NS_IMETHODIMP
+nsDNSServiceDiscovery::StopDiscovery(nsIDNSServiceDiscoveryListener* aListener)
+{
+  nsresult rv;
+
+  RefPtr<BrowseOperator> browserOp;
+  if (!mDiscoveryMap.Get(aListener, getter_AddRefs(browserOp))) {
+    return NS_OK;
+  }
+
+  browserOp->Cancel(); // cancel non-started operation
+  if (NS_WARN_IF(NS_FAILED(rv = browserOp->Stop()))) {
+    return rv;
+  }
+
+  mDiscoveryMap.Remove(aListener);
+  return NS_OK;
+}
+
+NS_IMETHODIMP
+nsDNSServiceDiscovery::RegisterService(nsIDNSServiceInfo* aServiceInfo,
+                                       nsIDNSRegistrationListener* aListener,
+                                       nsICancelable** aRetVal)
+{
+  MOZ_ASSERT(aRetVal);
+
+  nsresult rv;
+  if (NS_WARN_IF(NS_FAILED(rv = UnregisterService(aListener)))) {
+    return rv;
+  }
+
+  nsCOMPtr<nsICancelable> req = new RegisterRequest(this, aListener);
+  RefPtr<RegisterOperator> registerOp = new RegisterOperator(aServiceInfo,
+                                                               aListener);
+  if (NS_WARN_IF(NS_FAILED(rv = registerOp->Start()))) {
+    return rv;
+  }
+
+  mRegisterMap.Put(aListener, registerOp);
+
+  req.forget(aRetVal);
+
+  return NS_OK;
+}
+
+NS_IMETHODIMP
+nsDNSServiceDiscovery::UnregisterService(nsIDNSRegistrationListener* aListener)
+{
+  nsresult rv;
+
+  RefPtr<RegisterOperator> registerOp;
+  if (!mRegisterMap.Get(aListener, getter_AddRefs(registerOp))) {
+    return NS_OK;
+  }
+
+  registerOp->Cancel(); // cancel non-started operation
+  if (NS_WARN_IF(NS_FAILED(rv = registerOp->Stop()))) {
+    return rv;
+  }
+
+  mRegisterMap.Remove(aListener);
+  return NS_OK;
+}
+
+NS_IMETHODIMP
+nsDNSServiceDiscovery::ResolveService(nsIDNSServiceInfo* aServiceInfo,
+                                      nsIDNSServiceResolveListener* aListener)
+{
+  if (!ServiceCounter::IsServiceRunning()) {
+    return NS_ERROR_FAILURE;
+  }
+
+  nsresult rv;
+
+  RefPtr<ResolveOperator> resolveOp = new ResolveOperator(aServiceInfo,
+                                                            aListener);
+  if (NS_WARN_IF(NS_FAILED(rv = resolveOp->Start()))) {
+    return rv;
+  }
+
+  return NS_OK;
+}
+
+} // namespace net
+} // namespace mozilla