add ios platform helpers to fix issue with background tasks.

coreapi/linphonecore.c

@@ -2242,6 +2242,8 @@ static void linphone_core_init(LinphoneCore * lc, LinphoneCoreCbs *cbs, LpConfig
 #ifdef __ANDROID__
 	if (system_context)
 		lc->platform_helper = LinphonePrivate::createAndroidPlatformHelpers(lc, system_context);
+#elif TARGET_OS_IPHONE
+	lc->platform_helper = LinphonePrivate::createIosPlatformHelpers(lc, system_context);
 #endif
 	if (lc->platform_helper == NULL)
 		lc->platform_helper = new LinphonePrivate::StubbedPlatformHelpers(lc);

src/core/platform-helpers/ios-platform-helpers.cpp

@@ -0,0 +1,119 @@
+/*
+linphone
+Copyright (C) 2017 Belledonne Communications SARL
+
+This program is free software; you can redistribute it and/or
+modify it under the terms of the GNU General Public License
+as published by the Free Software Foundation; either version 2
+of the License, or (at your option) any later version.
+
+This program is distributed in the hope that it will be useful,
+but WITHOUT ANY WARRANTY; without even the implied warranty of
+MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+GNU General Public License for more details.
+
+You should have received a copy of the GNU General Public License
+along with this program; if not, write to the Free Software
+Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
+*/
+
+#ifdef __APPLE__
+#include "TargetConditionals.h"
+#endif
+
+#if TARGET_OS_IPHONE
+
+#include "private.h"
+#include "platform-helpers.h"
+
+
+
+namespace LinphonePrivate{
+
+class IosPlatformHelpers : public PlatformHelpers{
+public:
+	IosPlatformHelpers(LinphoneCore *lc, void *system_context);
+	virtual void setDnsServers();
+	virtual void acquireWifiLock();
+	virtual void releaseWifiLock();
+	virtual void acquireMcastLock();
+	virtual void releaseMcastLock();
+	virtual void acquireCpuLock();
+	virtual void releaseCpuLock();
+	~IosPlatformHelpers();
+private:
+	void bgTaskTimeout();
+	static void sBgTaskTimeout(void *data);
+	long int mCpuLockTaskId;
+	int mCpuLockCount;
+};
+
+
+IosPlatformHelpers::IosPlatformHelpers(LinphoneCore *lc, void *system_context) : PlatformHelpers(lc) {
+	mCpuLockCount = 0;
+	mCpuLockTaskId = 0;
+	ms_message("IosPlatformHelpers is fully initialised");
+}
+
+IosPlatformHelpers::~IosPlatformHelpers(){
+	
+}
+
+
+void IosPlatformHelpers::setDnsServers(){
+}
+
+void IosPlatformHelpers::acquireWifiLock(){
+}
+
+void IosPlatformHelpers::releaseWifiLock(){
+}
+
+void IosPlatformHelpers::acquireMcastLock(){
+}
+
+void IosPlatformHelpers::releaseMcastLock(){
+}
+
+void IosPlatformHelpers::bgTaskTimeout(){
+	ms_error("IosPlatformHelpers: the system requests that the cpu lock is released now.");
+	if (mCpuLockTaskId != 0){
+		belle_sip_end_background_task(mCpuLockTaskId);
+		mCpuLockTaskId = 0;
+	}
+}
+
+void IosPlatformHelpers::sBgTaskTimeout(void *data){
+	IosPlatformHelpers *zis = (IosPlatformHelpers*)data;
+	zis->bgTaskTimeout();
+}
+
+void IosPlatformHelpers::acquireCpuLock(){
+	if (mCpuLockCount == 0){
+		/* on iOS, cpu lock is implemented by a long running task (obcj-C) and it is abstracted by belle-sip,
+		so let's use belle-sip directly.*/
+		mCpuLockTaskId = belle_sip_begin_background_task("Liblinphone cpu lock", sBgTaskTimeout, this);
+	}
+	mCpuLockCount++;
+}
+
+void IosPlatformHelpers::releaseCpuLock(){
+	mCpuLockCount--;
+	if (mCpuLockCount == 0){
+		if (mCpuLockTaskId != 0){
+			belle_sip_end_background_task(mCpuLockTaskId);
+			mCpuLockTaskId = 0;
+		}else{
+			ms_error("IosPlatformHelpers::releaseCpuLock(): too late, the lock has been released already by the system.");
+		}
+	}
+}
+
+
+PlatformHelpers *createIosPlatformHelpers(LinphoneCore *lc, void *system_context){
+	return new IosPlatformHelpers(lc, system_context);
+}
+
+}//end of namespace
+
+#endif