michael@0: /* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
michael@0: /* This Source Code Form is subject to the terms of the Mozilla Public
michael@0:  * License, v. 2.0. If a copy of the MPL was not distributed with this
michael@0:  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
michael@0: 
michael@0: /*
michael@0:  * Maintains a circular buffer of recent messages, and notifies
michael@0:  * listeners when new messages are logged.
michael@0:  */
michael@0: 
michael@0: /* Threadsafe. */
michael@0: 
michael@0: #include "nsMemory.h"
michael@0: #include "nsCOMArray.h"
michael@0: #include "nsThreadUtils.h"
michael@0: 
michael@0: #include "nsConsoleService.h"
michael@0: #include "nsConsoleMessage.h"
michael@0: #include "nsIClassInfoImpl.h"
michael@0: #include "nsIConsoleListener.h"
michael@0: #include "nsPrintfCString.h"
michael@0: 
michael@0: #include "mozilla/Preferences.h"
michael@0: 
michael@0: #if defined(ANDROID)
michael@0: #include <android/log.h>
michael@0: #endif
michael@0: #ifdef XP_WIN
michael@0: #include <windows.h>
michael@0: #endif
michael@0: 
michael@0: using namespace mozilla;
michael@0: 
michael@0: NS_IMPL_ADDREF(nsConsoleService)
michael@0: NS_IMPL_RELEASE(nsConsoleService)
michael@0: NS_IMPL_CLASSINFO(nsConsoleService, nullptr, nsIClassInfo::THREADSAFE | nsIClassInfo::SINGLETON, NS_CONSOLESERVICE_CID)
michael@0: NS_IMPL_QUERY_INTERFACE_CI(nsConsoleService, nsIConsoleService)
michael@0: NS_IMPL_CI_INTERFACE_GETTER(nsConsoleService, nsIConsoleService)
michael@0: 
michael@0: static bool sLoggingEnabled = true;
michael@0: static bool sLoggingBuffered = true;
michael@0: 
michael@0: nsConsoleService::nsConsoleService()
michael@0:     : mMessages(nullptr)
michael@0:     , mCurrent(0)
michael@0:     , mFull(false)
michael@0:     , mDeliveringMessage(false)
michael@0:     , mLock("nsConsoleService.mLock")
michael@0: {
michael@0:     // XXX grab this from a pref!
michael@0:     // hm, but worry about circularity, bc we want to be able to report
michael@0:     // prefs errs...
michael@0:     mBufferSize = 250;
michael@0: }
michael@0: 
michael@0: nsConsoleService::~nsConsoleService()
michael@0: {
michael@0:     uint32_t i = 0;
michael@0:     while (i < mBufferSize && mMessages[i] != nullptr) {
michael@0:         NS_RELEASE(mMessages[i]);
michael@0:         i++;
michael@0:     }
michael@0: 
michael@0:     if (mMessages)
michael@0:         nsMemory::Free(mMessages);
michael@0: }
michael@0: 
michael@0: class AddConsolePrefWatchers : public nsRunnable
michael@0: {
michael@0: public:
michael@0:     AddConsolePrefWatchers(nsConsoleService* aConsole) : mConsole(aConsole) {}
michael@0: 
michael@0:     NS_IMETHOD Run()
michael@0:     {
michael@0:         Preferences::AddBoolVarCache(&sLoggingEnabled, "consoleservice.enabled", true);
michael@0:         Preferences::AddBoolVarCache(&sLoggingBuffered, "consoleservice.buffered", true);
michael@0:         if (!sLoggingBuffered) {
michael@0:             mConsole->Reset();
michael@0:         }
michael@0:         return NS_OK;
michael@0:     }
michael@0: 
michael@0: private:
michael@0:     nsRefPtr<nsConsoleService> mConsole;
michael@0: };
michael@0: 
michael@0: nsresult
michael@0: nsConsoleService::Init()
michael@0: {
michael@0:     mMessages = (nsIConsoleMessage **)
michael@0:         nsMemory::Alloc(mBufferSize * sizeof(nsIConsoleMessage *));
michael@0:     if (!mMessages)
michael@0:         return NS_ERROR_OUT_OF_MEMORY;
michael@0: 
michael@0:     // Array elements should be 0 initially for circular buffer algorithm.
michael@0:     memset(mMessages, 0, mBufferSize * sizeof(nsIConsoleMessage *));
michael@0: 
michael@0:     NS_DispatchToMainThread(new AddConsolePrefWatchers(this));
michael@0: 
michael@0:     return NS_OK;
michael@0: }
michael@0: 
michael@0: namespace {
michael@0: 
michael@0: class LogMessageRunnable : public nsRunnable
michael@0: {
michael@0: public:
michael@0:     LogMessageRunnable(nsIConsoleMessage* message, nsConsoleService* service)
michael@0:         : mMessage(message)
michael@0:         , mService(service)
michael@0:     { }
michael@0: 
michael@0:     NS_DECL_NSIRUNNABLE
michael@0: 
michael@0: private:
michael@0:     nsCOMPtr<nsIConsoleMessage> mMessage;
michael@0:     nsRefPtr<nsConsoleService> mService;
michael@0: };
michael@0: 
michael@0: typedef nsCOMArray<nsIConsoleListener> ListenerArrayType;
michael@0: 
michael@0: PLDHashOperator
michael@0: CollectCurrentListeners(nsISupports* aKey, nsIConsoleListener* aValue,
michael@0:                         void* closure)
michael@0: {
michael@0:     ListenerArrayType* listeners = static_cast<ListenerArrayType*>(closure);
michael@0:     listeners->AppendObject(aValue);
michael@0:     return PL_DHASH_NEXT;
michael@0: }
michael@0: 
michael@0: NS_IMETHODIMP
michael@0: LogMessageRunnable::Run()
michael@0: {
michael@0:     MOZ_ASSERT(NS_IsMainThread());
michael@0: 
michael@0:     // Snapshot of listeners so that we don't reenter this hash during
michael@0:     // enumeration.
michael@0:     nsCOMArray<nsIConsoleListener> listeners;
michael@0:     mService->EnumerateListeners(CollectCurrentListeners, &listeners);
michael@0: 
michael@0:     mService->SetIsDelivering();
michael@0: 
michael@0:     for (int32_t i = 0; i < listeners.Count(); ++i)
michael@0:         listeners[i]->Observe(mMessage);
michael@0: 
michael@0:     mService->SetDoneDelivering();
michael@0: 
michael@0:     return NS_OK;
michael@0: }
michael@0: 
michael@0: } // anonymous namespace
michael@0: 
michael@0: // nsIConsoleService methods
michael@0: NS_IMETHODIMP
michael@0: nsConsoleService::LogMessage(nsIConsoleMessage *message)
michael@0: {
michael@0:     return LogMessageWithMode(message, OutputToLog);
michael@0: }
michael@0: 
michael@0: nsresult
michael@0: nsConsoleService::LogMessageWithMode(nsIConsoleMessage *message, nsConsoleService::OutputMode outputMode)
michael@0: {
michael@0:     if (message == nullptr)
michael@0:         return NS_ERROR_INVALID_ARG;
michael@0: 
michael@0:     if (!sLoggingEnabled) {
michael@0:         return NS_OK;
michael@0:     }
michael@0: 
michael@0:     if (NS_IsMainThread() && mDeliveringMessage) {
michael@0:         nsCString msg;
michael@0:         message->ToString(msg);
michael@0:         NS_WARNING(nsPrintfCString("Reentrancy error: some client attempted "
michael@0:             "to display a message to the console while in a console listener. "
michael@0:             "The following message was discarded: \"%s\"", msg.get()).get());
michael@0:         return NS_ERROR_FAILURE;
michael@0:     }
michael@0: 
michael@0:     nsRefPtr<LogMessageRunnable> r;
michael@0:     nsIConsoleMessage *retiredMessage;
michael@0: 
michael@0:     if (sLoggingBuffered) {
michael@0:         NS_ADDREF(message); // early, in case it's same as replaced below.
michael@0:     }
michael@0: 
michael@0:     /*
michael@0:      * Lock while updating buffer, and while taking snapshot of
michael@0:      * listeners array.
michael@0:      */
michael@0:     {
michael@0:         MutexAutoLock lock(mLock);
michael@0: 
michael@0: #if defined(ANDROID)
michael@0:         if (outputMode == OutputToLog)
michael@0:         {
michael@0:             nsCString msg;
michael@0:             message->ToString(msg);
michael@0:             __android_log_print(ANDROID_LOG_ERROR, "GeckoConsole",
michael@0:                         "%s", msg.get());
michael@0:         }
michael@0: #endif
michael@0: #ifdef XP_WIN
michael@0:         if (IsDebuggerPresent()) {
michael@0:             nsString msg;
michael@0:             message->GetMessageMoz(getter_Copies(msg));
michael@0:             msg.AppendLiteral("\n");
michael@0:             OutputDebugStringW(msg.get());
michael@0:         }
michael@0: #endif
michael@0: 
michael@0:         /*
michael@0:          * If there's already a message in the slot we're about to replace,
michael@0:          * we've wrapped around, and we need to release the old message.  We
michael@0:          * save a pointer to it, so we can release below outside the lock.
michael@0:          */
michael@0:         retiredMessage = mMessages[mCurrent];
michael@0: 
michael@0:         if (sLoggingBuffered) {
michael@0:             mMessages[mCurrent++] = message;
michael@0:             if (mCurrent == mBufferSize) {
michael@0:                 mCurrent = 0; // wrap around.
michael@0:                 mFull = true;
michael@0:             }
michael@0:         }
michael@0: 
michael@0:         if (mListeners.Count() > 0) {
michael@0:             r = new LogMessageRunnable(message, this);
michael@0:         }
michael@0:     }
michael@0: 
michael@0:     if (retiredMessage != nullptr)
michael@0:         NS_RELEASE(retiredMessage);
michael@0: 
michael@0:     if (r)
michael@0:         NS_DispatchToMainThread(r);
michael@0: 
michael@0:     return NS_OK;
michael@0: }
michael@0: 
michael@0: void
michael@0: nsConsoleService::EnumerateListeners(ListenerHash::EnumReadFunction aFunction,
michael@0:                                      void* aClosure)
michael@0: {
michael@0:     MutexAutoLock lock(mLock);
michael@0:     mListeners.EnumerateRead(aFunction, aClosure);
michael@0: }
michael@0: 
michael@0: NS_IMETHODIMP
michael@0: nsConsoleService::LogStringMessage(const char16_t *message)
michael@0: {
michael@0:     if (!sLoggingEnabled) {
michael@0:         return NS_OK;
michael@0:     }
michael@0: 
michael@0:     nsRefPtr<nsConsoleMessage> msg(new nsConsoleMessage(message));
michael@0:     return this->LogMessage(msg);
michael@0: }
michael@0: 
michael@0: NS_IMETHODIMP
michael@0: nsConsoleService::GetMessageArray(uint32_t *count, nsIConsoleMessage ***messages)
michael@0: {
michael@0:     nsIConsoleMessage **messageArray;
michael@0: 
michael@0:     /*
michael@0:      * Lock the whole method, as we don't want anyone mucking with mCurrent or
michael@0:      * mFull while we're copying out the buffer.
michael@0:      */
michael@0:     MutexAutoLock lock(mLock);
michael@0: 
michael@0:     if (mCurrent == 0 && !mFull) {
michael@0:         /*
michael@0:          * Make a 1-length output array so that nobody gets confused,
michael@0:          * and return a count of 0.  This should result in a 0-length
michael@0:          * array object when called from script.
michael@0:          */
michael@0:         messageArray = (nsIConsoleMessage **)
michael@0:             nsMemory::Alloc(sizeof (nsIConsoleMessage *));
michael@0:         *messageArray = nullptr;
michael@0:         *messages = messageArray;
michael@0:         *count = 0;
michael@0: 
michael@0:         return NS_OK;
michael@0:     }
michael@0: 
michael@0:     uint32_t resultSize = mFull ? mBufferSize : mCurrent;
michael@0:     messageArray =
michael@0:         (nsIConsoleMessage **)nsMemory::Alloc((sizeof (nsIConsoleMessage *))
michael@0:                                               * resultSize);
michael@0: 
michael@0:     if (messageArray == nullptr) {
michael@0:         *messages = nullptr;
michael@0:         *count = 0;
michael@0:         return NS_ERROR_FAILURE;
michael@0:     }
michael@0: 
michael@0:     uint32_t i;
michael@0:     if (mFull) {
michael@0:         for (i = 0; i < mBufferSize; i++) {
michael@0:             // if full, fill the buffer starting from mCurrent (which'll be
michael@0:             // oldest) wrapping around the buffer to the most recent.
michael@0:             messageArray[i] = mMessages[(mCurrent + i) % mBufferSize];
michael@0:             NS_ADDREF(messageArray[i]);
michael@0:         }
michael@0:     } else {
michael@0:         for (i = 0; i < mCurrent; i++) {
michael@0:             messageArray[i] = mMessages[i];
michael@0:             NS_ADDREF(messageArray[i]);
michael@0:         }
michael@0:     }
michael@0:     *count = resultSize;
michael@0:     *messages = messageArray;
michael@0: 
michael@0:     return NS_OK;
michael@0: }
michael@0: 
michael@0: NS_IMETHODIMP
michael@0: nsConsoleService::RegisterListener(nsIConsoleListener *listener)
michael@0: {
michael@0:     if (!NS_IsMainThread()) {
michael@0:         NS_ERROR("nsConsoleService::RegisterListener is main thread only.");
michael@0:         return NS_ERROR_NOT_SAME_THREAD;
michael@0:     }
michael@0: 
michael@0:     nsCOMPtr<nsISupports> canonical = do_QueryInterface(listener);
michael@0: 
michael@0:     MutexAutoLock lock(mLock);
michael@0:     if (mListeners.GetWeak(canonical)) {
michael@0:         // Reregistering a listener isn't good
michael@0:         return NS_ERROR_FAILURE;
michael@0:     }
michael@0:     mListeners.Put(canonical, listener);
michael@0:     return NS_OK;
michael@0: }
michael@0: 
michael@0: NS_IMETHODIMP
michael@0: nsConsoleService::UnregisterListener(nsIConsoleListener *listener)
michael@0: {
michael@0:     if (!NS_IsMainThread()) {
michael@0:         NS_ERROR("nsConsoleService::UnregisterListener is main thread only.");
michael@0:         return NS_ERROR_NOT_SAME_THREAD;
michael@0:     }
michael@0: 
michael@0:     nsCOMPtr<nsISupports> canonical = do_QueryInterface(listener);
michael@0: 
michael@0:     MutexAutoLock lock(mLock);
michael@0: 
michael@0:     if (!mListeners.GetWeak(canonical)) {
michael@0:         // Unregistering a listener that was never registered?
michael@0:         return NS_ERROR_FAILURE;
michael@0:     }
michael@0:     mListeners.Remove(canonical);
michael@0:     return NS_OK;
michael@0: }
michael@0: 
michael@0: NS_IMETHODIMP
michael@0: nsConsoleService::Reset()
michael@0: {
michael@0:     /*
michael@0:      * Make sure nobody trips into the buffer while it's being reset
michael@0:      */
michael@0:     MutexAutoLock lock(mLock);
michael@0: 
michael@0:     mCurrent = 0;
michael@0:     mFull = false;
michael@0: 
michael@0:     /*
michael@0:      * Free all messages stored so far (cf. destructor)
michael@0:      */
michael@0:     for (uint32_t i = 0; i < mBufferSize && mMessages[i] != nullptr; i++)
michael@0:         NS_RELEASE(mMessages[i]);
michael@0: 
michael@0:     return NS_OK;
michael@0: }