1 files changed, 519 insertions, 0 deletions
diff --git a/xpcom/base/nsConsoleService.cpp b/xpcom/base/nsConsoleService.cpp
new file mode 100644
index 0000000000..1b55b6f974
--- /dev/null
+++ b/xpcom/base/nsConsoleService.cpp
@@ -0,0 +1,519 @@
+/* -*- 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/. */
+
+/*
+ * Maintains a circular buffer of recent messages, and notifies
+ * listeners when new messages are logged.
+ */
+
+/* Threadsafe. */
+
+#include "nsCOMArray.h"
+#include "nsThreadUtils.h"
+
+#include "nsConsoleService.h"
+#include "nsConsoleMessage.h"
+#include "nsIClassInfoImpl.h"
+#include "nsIConsoleListener.h"
+#include "nsIObserverService.h"
+#include "nsPrintfCString.h"
+#include "nsProxyRelease.h"
+#include "nsIScriptError.h"
+#include "nsISupportsPrimitives.h"
+#include "mozilla/dom/WindowGlobalParent.h"
+#include "mozilla/dom/ContentParent.h"
+#include "mozilla/dom/BrowserParent.h"
+
+#include "mozilla/SchedulerGroup.h"
+#include "mozilla/Services.h"
+
+#if defined(ANDROID)
+#  include <android/log.h>
+#  include "mozilla/dom/ContentChild.h"
+#  include "mozilla/StaticPrefs_consoleservice.h"
+#endif
+#ifdef XP_WIN
+#  include <windows.h>
+#endif
+
+using namespace mozilla;
+
+NS_IMPL_ADDREF(nsConsoleService)
+NS_IMPL_RELEASE(nsConsoleService)
+NS_IMPL_CLASSINFO(nsConsoleService, nullptr,
+                  nsIClassInfo::THREADSAFE | nsIClassInfo::SINGLETON,
+                  NS_CONSOLESERVICE_CID)
+NS_IMPL_QUERY_INTERFACE_CI(nsConsoleService, nsIConsoleService, nsIObserver)
+NS_IMPL_CI_INTERFACE_GETTER(nsConsoleService, nsIConsoleService, nsIObserver)
+
+static const bool gLoggingEnabled = true;
+static const bool gLoggingBuffered = true;
+#ifdef XP_WIN
+static bool gLoggingToDebugger = true;
+#endif  // XP_WIN
+
+nsConsoleService::MessageElement::~MessageElement() = default;
+
+nsConsoleService::nsConsoleService()
+    : mCurrentSize(0),
+      // XXX grab this from a pref!
+      // hm, but worry about circularity, bc we want to be able to report
+      // prefs errs...
+      mMaximumSize(250),
+      mDeliveringMessage(false),
+      mLock("nsConsoleService.mLock") {
+#ifdef XP_WIN
+  // This environment variable controls whether the console service
+  // should be prevented from putting output to the attached debugger.
+  // It only affects the Windows platform.
+  //
+  // To disable OutputDebugString, set:
+  //   MOZ_CONSOLESERVICE_DISABLE_DEBUGGER_OUTPUT=1
+  //
+  const char* disableDebugLoggingVar =
+      getenv("MOZ_CONSOLESERVICE_DISABLE_DEBUGGER_OUTPUT");
+  gLoggingToDebugger =
+      !disableDebugLoggingVar || (disableDebugLoggingVar[0] == '0');
+#endif  // XP_WIN
+}
+
+void nsConsoleService::ClearMessagesForWindowID(const uint64_t innerID) {
+  MOZ_RELEASE_ASSERT(NS_IsMainThread());
+  MutexAutoLock lock(mLock);
+
+  for (MessageElement* e = mMessages.getFirst(); e != nullptr;) {
+    // Only messages implementing nsIScriptError interface expose the
+    // inner window ID.
+    nsCOMPtr<nsIScriptError> scriptError = do_QueryInterface(e->Get());
+    if (!scriptError) {
+      e = e->getNext();
+      continue;
+    }
+    uint64_t innerWindowID;
+    nsresult rv = scriptError->GetInnerWindowID(&innerWindowID);
+    if (NS_FAILED(rv) || innerWindowID != innerID) {
+      e = e->getNext();
+      continue;
+    }
+
+    MessageElement* next = e->getNext();
+    e->remove();
+    delete e;
+    mCurrentSize--;
+    MOZ_ASSERT(mCurrentSize < mMaximumSize);
+
+    e = next;
+  }
+}
+
+void nsConsoleService::ClearMessages() {
+  // NB: A lock is not required here as it's only called from |Reset| which
+  //     locks for us and from the dtor.
+  while (!mMessages.isEmpty()) {
+    MessageElement* e = mMessages.popFirst();
+    delete e;
+  }
+  mCurrentSize = 0;
+}
+
+nsConsoleService::~nsConsoleService() {
+  MOZ_RELEASE_ASSERT(NS_IsMainThread());
+
+  ClearMessages();
+}
+
+class AddConsolePrefWatchers : public Runnable {
+ public:
+  explicit AddConsolePrefWatchers(nsConsoleService* aConsole)
+      : mozilla::Runnable("AddConsolePrefWatchers"), mConsole(aConsole) {}
+
+  NS_IMETHOD Run() override {
+    nsCOMPtr<nsIObserverService> obs = mozilla::services::GetObserverService();
+    MOZ_ASSERT(obs);
+    obs->AddObserver(mConsole, NS_XPCOM_SHUTDOWN_OBSERVER_ID, false);
+    obs->AddObserver(mConsole, "inner-window-destroyed", false);
+
+    if (!gLoggingBuffered) {
+      mConsole->Reset();
+    }
+    return NS_OK;
+  }
+
+ private:
+  RefPtr<nsConsoleService> mConsole;
+};
+
+nsresult nsConsoleService::Init() {
+  NS_DispatchToMainThread(new AddConsolePrefWatchers(this));
+
+  return NS_OK;
+}
+
+nsresult nsConsoleService::MaybeForwardScriptError(nsIConsoleMessage* aMessage,
+                                                   bool* sent) {
+  *sent = false;
+
+  nsCOMPtr<nsIScriptError> scriptError = do_QueryInterface(aMessage);
+  if (!scriptError) {
+    // Not an nsIScriptError
+    return NS_OK;
+  }
+
+  uint64_t windowID;
+  nsresult rv;
+  rv = scriptError->GetInnerWindowID(&windowID);
+  NS_ENSURE_SUCCESS(rv, rv);
+  if (!windowID) {
+    // Does not set window id
+    return NS_OK;
+  }
+
+  RefPtr<mozilla::dom::WindowGlobalParent> windowGlobalParent =
+      mozilla::dom::WindowGlobalParent::GetByInnerWindowId(windowID);
+  if (!windowGlobalParent) {
+    // Could not find parent window by id
+    return NS_OK;
+  }
+
+  RefPtr<mozilla::dom::BrowserParent> browserParent =
+      windowGlobalParent->GetBrowserParent();
+  if (!browserParent) {
+    return NS_OK;
+  }
+
+  mozilla::dom::ContentParent* contentParent = browserParent->Manager();
+  if (!contentParent) {
+    return NS_ERROR_FAILURE;
+  }
+
+  nsAutoString msg, sourceName, sourceLine;
+  nsCString category;
+  uint32_t lineNum, colNum, flags;
+  uint64_t innerWindowId;
+  bool fromPrivateWindow, fromChromeContext;
+
+  rv = scriptError->GetErrorMessage(msg);
+  NS_ENSURE_SUCCESS(rv, rv);
+  rv = scriptError->GetSourceName(sourceName);
+  NS_ENSURE_SUCCESS(rv, rv);
+  rv = scriptError->GetSourceLine(sourceLine);
+  NS_ENSURE_SUCCESS(rv, rv);
+
+  rv = scriptError->GetCategory(getter_Copies(category));
+  NS_ENSURE_SUCCESS(rv, rv);
+  rv = scriptError->GetLineNumber(&lineNum);
+  NS_ENSURE_SUCCESS(rv, rv);
+  rv = scriptError->GetColumnNumber(&colNum);
+  NS_ENSURE_SUCCESS(rv, rv);
+  rv = scriptError->GetFlags(&flags);
+  NS_ENSURE_SUCCESS(rv, rv);
+  rv = scriptError->GetIsFromPrivateWindow(&fromPrivateWindow);
+  NS_ENSURE_SUCCESS(rv, rv);
+  rv = scriptError->GetIsFromChromeContext(&fromChromeContext);
+  NS_ENSURE_SUCCESS(rv, rv);
+  rv = scriptError->GetInnerWindowID(&innerWindowId);
+  NS_ENSURE_SUCCESS(rv, rv);
+
+  *sent = contentParent->SendScriptError(
+      msg, sourceName, sourceLine, lineNum, colNum, flags, category,
+      fromPrivateWindow, innerWindowId, fromChromeContext);
+  return NS_OK;
+}
+
+namespace {
+
+class LogMessageRunnable : public Runnable {
+ public:
+  LogMessageRunnable(nsIConsoleMessage* aMessage, nsConsoleService* aService)
+      : mozilla::Runnable("LogMessageRunnable"),
+        mMessage(aMessage),
+        mService(aService) {}
+
+  NS_DECL_NSIRUNNABLE
+
+ private:
+  nsCOMPtr<nsIConsoleMessage> mMessage;
+  RefPtr<nsConsoleService> mService;
+};
+
+NS_IMETHODIMP
+LogMessageRunnable::Run() {
+  // Snapshot of listeners so that we don't reenter this hash during
+  // enumeration.
+  nsCOMArray<nsIConsoleListener> listeners;
+  mService->CollectCurrentListeners(listeners);
+
+  mService->SetIsDelivering();
+
+  for (int32_t i = 0; i < listeners.Count(); ++i) {
+    listeners[i]->Observe(mMessage);
+  }
+
+  mService->SetDoneDelivering();
+
+  return NS_OK;
+}
+
+}  // namespace
+
+// nsIConsoleService methods
+NS_IMETHODIMP
+nsConsoleService::LogMessage(nsIConsoleMessage* aMessage) {
+  return LogMessageWithMode(aMessage, nsIConsoleService::OutputToLog);
+}
+
+// This can be called off the main thread.
+nsresult nsConsoleService::LogMessageWithMode(
+    nsIConsoleMessage* aMessage, nsIConsoleService::OutputMode aOutputMode) {
+  if (!aMessage) {
+    return NS_ERROR_INVALID_ARG;
+  }
+
+  if (!gLoggingEnabled) {
+    return NS_OK;
+  }
+
+  if (NS_IsMainThread() && mDeliveringMessage) {
+    nsCString msg;
+    aMessage->ToString(msg);
+    NS_WARNING(
+        nsPrintfCString(
+            "Reentrancy error: some client attempted to display a message to "
+            "the console while in a console listener. The following message "
+            "was discarded: \"%s\"",
+            msg.get())
+            .get());
+    return NS_ERROR_FAILURE;
+  }
+
+  if (XRE_IsParentProcess() && NS_IsMainThread()) {
+    // If mMessage is a scriptError with an innerWindowId set,
+    // forward it to the matching ContentParent
+    // This enables logging from parent to content process
+    bool sent;
+    nsresult rv = MaybeForwardScriptError(aMessage, &sent);
+    NS_ENSURE_SUCCESS(rv, rv);
+    if (sent) {
+      return NS_OK;
+    }
+  }
+
+  RefPtr<LogMessageRunnable> r;
+  nsCOMPtr<nsIConsoleMessage> retiredMessage;
+
+  /*
+   * Lock while updating buffer, and while taking snapshot of
+   * listeners array.
+   */
+  {
+    MutexAutoLock lock(mLock);
+
+#if defined(ANDROID)
+    if (StaticPrefs::consoleservice_logcat() && aOutputMode == OutputToLog) {
+      nsCString msg;
+      aMessage->ToString(msg);
+
+      /** Attempt to use the process name as the log tag. */
+      mozilla::dom::ContentChild* child =
+          mozilla::dom::ContentChild::GetSingleton();
+      nsCString appName;
+      if (child) {
+        child->GetProcessName(appName);
+      } else {
+        appName = "GeckoConsole";
+      }
+
+      uint32_t logLevel = 0;
+      aMessage->GetLogLevel(&logLevel);
+
+      android_LogPriority logPriority = ANDROID_LOG_INFO;
+      switch (logLevel) {
+        case nsIConsoleMessage::debug:
+          logPriority = ANDROID_LOG_DEBUG;
+          break;
+        case nsIConsoleMessage::info:
+          logPriority = ANDROID_LOG_INFO;
+          break;
+        case nsIConsoleMessage::warn:
+          logPriority = ANDROID_LOG_WARN;
+          break;
+        case nsIConsoleMessage::error:
+          logPriority = ANDROID_LOG_ERROR;
+          break;
+      }
+
+      __android_log_print(logPriority, appName.get(), "%s", msg.get());
+    }
+#endif
+#ifdef XP_WIN
+    if (gLoggingToDebugger && IsDebuggerPresent()) {
+      nsString msg;
+      aMessage->GetMessageMoz(msg);
+      msg.Append('\n');
+      OutputDebugStringW(msg.get());
+    }
+#endif
+
+    if (gLoggingBuffered) {
+      MessageElement* e = new MessageElement(aMessage);
+      mMessages.insertBack(e);
+      if (mCurrentSize != mMaximumSize) {
+        mCurrentSize++;
+      } else {
+        MessageElement* p = mMessages.popFirst();
+        MOZ_ASSERT(p);
+        p->swapMessage(retiredMessage);
+        delete p;
+      }
+    }
+
+    if (mListeners.Count() > 0) {
+      r = new LogMessageRunnable(aMessage, this);
+    }
+  }
+
+  if (retiredMessage) {
+    // Release |retiredMessage| on the main thread in case it is an instance of
+    // a mainthread-only class like nsScriptErrorWithStack and we're off the
+    // main thread.
+    NS_ReleaseOnMainThread("nsConsoleService::retiredMessage",
+                           retiredMessage.forget());
+  }
+
+  if (r) {
+    // avoid failing in XPCShell tests
+    nsCOMPtr<nsIThread> mainThread = do_GetMainThread();
+    if (mainThread) {
+      SchedulerGroup::Dispatch(TaskCategory::Other, r.forget());
+    }
+  }
+
+  return NS_OK;
+}
+
+void nsConsoleService::CollectCurrentListeners(
+    nsCOMArray<nsIConsoleListener>& aListeners) {
+  MutexAutoLock lock(mLock);
+  // XXX When MakeBackInserter(nsCOMArray<T>&) is added, we can do:
+  // AppendToArray(aListeners, mListeners.Values());
+  for (const auto& listener : mListeners.Values()) {
+    aListeners.AppendObject(listener);
+  }
+}
+
+NS_IMETHODIMP
+nsConsoleService::LogStringMessage(const char16_t* aMessage) {
+  if (!gLoggingEnabled) {
+    return NS_OK;
+  }
+
+  RefPtr<nsConsoleMessage> msg(new nsConsoleMessage(
+      aMessage ? nsDependentString(aMessage) : EmptyString()));
+  return LogMessage(msg);
+}
+
+NS_IMETHODIMP
+nsConsoleService::GetMessageArray(
+    nsTArray<RefPtr<nsIConsoleMessage>>& aMessages) {
+  MOZ_RELEASE_ASSERT(NS_IsMainThread());
+
+  MutexAutoLock lock(mLock);
+
+  if (mMessages.isEmpty()) {
+    return NS_OK;
+  }
+
+  MOZ_ASSERT(mCurrentSize <= mMaximumSize);
+  aMessages.SetCapacity(mCurrentSize);
+
+  for (MessageElement* e = mMessages.getFirst(); e != nullptr;
+       e = e->getNext()) {
+    aMessages.AppendElement(e->Get());
+  }
+
+  return NS_OK;
+}
+
+NS_IMETHODIMP
+nsConsoleService::RegisterListener(nsIConsoleListener* aListener) {
+  if (!NS_IsMainThread()) {
+    NS_ERROR("nsConsoleService::RegisterListener is main thread only.");
+    return NS_ERROR_NOT_SAME_THREAD;
+  }
+
+  nsCOMPtr<nsISupports> canonical = do_QueryInterface(aListener);
+  MOZ_ASSERT(canonical);
+
+  MutexAutoLock lock(mLock);
+  return mListeners.WithEntryHandle(canonical, [&](auto&& entry) {
+    if (entry) {
+      // Reregistering a listener isn't good
+      return NS_ERROR_FAILURE;
+    }
+    entry.Insert(aListener);
+    return NS_OK;
+  });
+}
+
+NS_IMETHODIMP
+nsConsoleService::UnregisterListener(nsIConsoleListener* aListener) {
+  if (!NS_IsMainThread()) {
+    NS_ERROR("nsConsoleService::UnregisterListener is main thread only.");
+    return NS_ERROR_NOT_SAME_THREAD;
+  }
+
+  nsCOMPtr<nsISupports> canonical = do_QueryInterface(aListener);
+
+  MutexAutoLock lock(mLock);
+
+  return mListeners.Remove(canonical)
+             ? NS_OK
+             // Unregistering a listener that was never registered?
+             : NS_ERROR_FAILURE;
+}
+
+NS_IMETHODIMP
+nsConsoleService::Reset() {
+  MOZ_RELEASE_ASSERT(NS_IsMainThread());
+
+  /*
+   * Make sure nobody trips into the buffer while it's being reset
+   */
+  MutexAutoLock lock(mLock);
+
+  ClearMessages();
+  return NS_OK;
+}
+
+NS_IMETHODIMP
+nsConsoleService::ResetWindow(uint64_t windowInnerId) {
+  MOZ_RELEASE_ASSERT(NS_IsMainThread());
+
+  ClearMessagesForWindowID(windowInnerId);
+  return NS_OK;
+}
+
+NS_IMETHODIMP
+nsConsoleService::Observe(nsISupports* aSubject, const char* aTopic,
+                          const char16_t* aData) {
+  if (!strcmp(aTopic, NS_XPCOM_SHUTDOWN_OBSERVER_ID)) {
+    // Dump all our messages, in case any are cycle collected.
+    Reset();
+    // We could remove ourselves from the observer service, but it is about to
+    // drop all observers anyways, so why bother.
+  } else if (!strcmp(aTopic, "inner-window-destroyed")) {
+    nsCOMPtr<nsISupportsPRUint64> supportsInt = do_QueryInterface(aSubject);
+    MOZ_ASSERT(supportsInt);
+
+    uint64_t windowId;
+    MOZ_ALWAYS_SUCCEEDS(supportsInt->GetData(&windowId));
+
+    ClearMessagesForWindowID(windowId);
+  } else {
+    MOZ_CRASH();
+  }
+  return NS_OK;
+}