Refactor OpenThread Global Variables into a Single Context Structure (#357)

* Refactor OpenThread to contain all global/static variables in a single context structure.

doc/spinel-protocol-src/Makefile

@@ -89,4 +89,3 @@ draft-spinel-protocol-bis.xml: \
 	spinel-tech-thread.md \
 	spinel-test-vectors.md \
 	$(NULL)
-

include/openthread-types.h

@@ -44,6 +44,26 @@
 extern "C" {
 #endif
 
+#ifdef _WIN32
+#ifdef WINDOWS_KERNEL
+#include <ntdef.h>
+#else
+#include <windows.h>
+#endif
+#else
+#ifndef CONTAINING_RECORD
+/*#pragma GCC diagnostic push
+#pragma GCC diagnostic ignored "-Winvalid-offsetof"
+#define CONTAINING_RECORD(address, type, field) \
+    ((type *)((uint8_t*)(address) - offsetof(type, field)))
+#pragma GCC diagnostic pop*/
+#define BASE 0x1
+#define myoffsetof(s,m) (((size_t)&(((s*)BASE)->m))-BASE)
+#define CONTAINING_RECORD(address, type, field) \
+    ((type *)((uint8_t*)(address) - myoffsetof(type, field)))
+#endif
+#endif
+
 /**
  * This type represents the OpenThread instance structure.
  */

include/openthread.h

@@ -1621,6 +1621,8 @@ void otPlatformReset(otInstance *aInstance);
 /**
  * Get the ROUTER_DOWNGRADE_THRESHOLD parameter used in the Router role.
  *
+ * @param[in]  aInstance  A pointer to an OpenThread instance.
+ *
  * @returns The ROUTER_DOWNGRADE_THRESHOLD value.
  *
  * @sa otSetRouterDowngradeThreshold
@@ -1630,6 +1632,7 @@ uint8_t otGetRouterDowngradeThreshold(otInstance *aInstance);
 /**
  * Set the ROUTER_DOWNGRADE_THRESHOLD parameter used in the Leader role.
  *
+ * @param[in]  aInstance   A pointer to an OpenThread instance.
  * @param[in]  aThreshold  The ROUTER_DOWNGRADE_THRESHOLD value.
  *
  * @sa otGetRouterDowngradeThreshold

src/cli/cli.cpp

@@ -42,6 +42,7 @@
 #include <string.h>
 
 #include <openthread.h>
+#include <openthread-instance.h>
 #include <openthread-diag.h>
 #include <commissioning/commissioner.h>
 #include <commissioning/joiner.h>
@@ -59,8 +60,6 @@ using Thread::Encoding::BigEndian::HostSwap32;
 
 namespace Thread {
 
-extern Ip6::Ip6 *sIp6;
-
 namespace Cli {
 
 const struct Command Interpreter::sCommands[] =
@@ -133,10 +132,10 @@ Interpreter::Interpreter(otInstance *aInstance):
     sLength(8),
     sCount(1),
     sInterval(1000),
-    sPingTimer(sIp6->mTimerScheduler, &Interpreter::s_HandlePingTimer, this),
+    sPingTimer(aInstance->mIp6.mTimerScheduler, &Interpreter::s_HandlePingTimer, this),
     mInstance(aInstance)
 {
-    sIp6->mIcmp.SetEchoReplyHandler(&s_HandleEchoResponse, this);
+    mInstance->mIp6.mIcmp.SetEchoReplyHandler(&s_HandleEchoResponse, this);
     otSetStateChangedCallback(mInstance, &Interpreter::s_HandleNetifStateChanged, this);
 }
 
@@ -1142,11 +1141,11 @@ void Interpreter::HandlePingTimer()
     uint32_t timestamp = HostSwap32(Timer::GetNow());
     Message *message;
 
-    VerifyOrExit((message = sIp6->mIcmp.NewMessage(0)) != NULL, error = kThreadError_NoBufs);
+    VerifyOrExit((message = mInstance->mIp6.mIcmp.NewMessage(0)) != NULL, error = kThreadError_NoBufs);
     SuccessOrExit(error = message->Append(&timestamp, sizeof(timestamp)));
     SuccessOrExit(error = message->SetLength(sLength));
 
-    SuccessOrExit(error = sIp6->mIcmp.SendEchoRequest(*message, sMessageInfo));
+    SuccessOrExit(error = mInstance->mIp6.mIcmp.SendEchoRequest(*message, sMessageInfo));
     sCount--;
 
 exit:

src/core/Makefile.am

@@ -111,6 +111,7 @@ endif  # OPENTHREAD_ENABLE_DTLS
 noinst_HEADERS                      = \
     openthread-core-config.h          \
     openthread-core-default-config.h  \
+    openthread-instance.h             \
     coap/coap_header.hpp              \
     coap/coap_server.hpp              \
     common/code_utils.hpp             \

src/core/common/code_utils.hpp

@@ -36,6 +36,10 @@
 
 #include <stdbool.h>
 
+// Calculates the aligned variable size.
+#define otALIGNED_VAR_SIZE(size, align_type)            \
+    (((size) + (sizeof (align_type) - 1)) / sizeof (align_type))
+
 // Allocate the structure using "raw" storage.
 #define otDEFINE_ALIGNED_VAR(name, size, align_type)            \
     align_type name[(((size) + (sizeof (align_type) - 1)) / sizeof (align_type))]

src/core/common/message.cpp

@@ -35,6 +35,7 @@
 
 #include <common/code_utils.hpp>
 #include <common/debug.hpp>
+#include <common/logging.hpp>
 #include <common/message.hpp>
 #include <common/logging.hpp>
 #include <net/ip6.hpp>

src/core/common/tasklet.cpp

@@ -35,6 +35,7 @@
 #include <common/code_utils.hpp>
 #include <common/debug.hpp>
 #include <common/tasklet.hpp>
+#include <net/ip6.hpp>
 
 namespace Thread {
 
@@ -67,7 +68,7 @@ ThreadError TaskletScheduler::Post(Tasklet &aTasklet)
     {
         mHead = &aTasklet;
         mTail = &aTasklet;
-        otSignalTaskletPending(NULL);
+        otSignalTaskletPending(aTasklet.mScheduler.GetIp6()->GetInstance());
     }
     else
     {
@@ -120,4 +121,9 @@ void TaskletScheduler::ProcessQueuedTasklets(void)
     }
 }
 
+Ip6::Ip6 *TaskletScheduler::GetIp6()
+{
+    return Ip6::Ip6FromTaskletScheduler(this);
+}
+
 }  // namespace Thread

src/core/common/tasklet.hpp

@@ -38,6 +38,8 @@
 
 namespace Thread {
 
+namespace Ip6 { class Ip6; }
+
 class TaskletScheduler;
 
 /**
@@ -130,6 +132,14 @@ public:
      */
     void ProcessQueuedTasklets(void);
 
+    /**
+     * This method returns the pointer to the parent Ip6 structure.
+     *
+     * @returns The pointer to the parent Ip6 structure.
+     *
+     */
+    Ip6::Ip6 *GetIp6();
+
 private:
     Tasklet *PopTasklet(void);
     Tasklet *mHead;

src/core/common/timer.cpp

@@ -33,18 +33,17 @@
 
 #include <common/code_utils.hpp>
 #include <common/timer.hpp>
+#include <common/debug.hpp>
+#include <common/logging.hpp>
 #include <net/ip6.hpp>
 #include <platform/alarm.h>
+#include <openthread-instance.h>
 
 namespace Thread {
 
-// FIXME: the otPlatAlarm callback should provide the context
-static TimerScheduler *sTimerScheduler;
-
 TimerScheduler::TimerScheduler(void):
     mHead(NULL)
 {
-    sTimerScheduler = this;
 }
 
 void TimerScheduler::Add(Timer &aTimer)
@@ -136,23 +135,23 @@ void TimerScheduler::SetAlarm(void)
 
     if (mHead == NULL)
     {
-        otPlatAlarmStop(NULL);
+        otPlatAlarmStop(GetIp6()->GetInstance());
     }
     else
     {
         elapsed = now - mHead->mT0;
         remaining = (mHead->mDt > elapsed) ? mHead->mDt - elapsed : 0;
 
-        otPlatAlarmStartAt(NULL, now, remaining);
+        otPlatAlarmStartAt(GetIp6()->GetInstance(), now, remaining);
     }
 }
 
-extern "C" void otPlatAlarmFired(otInstance *)
+extern "C" void otPlatAlarmFired(otInstance *aInstance)
 {
-    sTimerScheduler->FireTimers();
+    aInstance->mIp6.mTimerScheduler.FireTimers();
 }
 
-void TimerScheduler::FireTimers(void)
+void TimerScheduler::FireTimers()
 {
     uint32_t now = otPlatAlarmGetNow();
     uint32_t elapsed;
@@ -178,6 +177,11 @@ void TimerScheduler::FireTimers(void)
     }
 }
 
+Ip6::Ip6 *TimerScheduler::GetIp6()
+{
+    return Ip6::Ip6FromTimerScheduler(this);
+}
+
 bool TimerScheduler::TimerCompare(const Timer &aTimerA, const Timer &aTimerB)
 {
     uint32_t now = otPlatAlarmGetNow();

src/core/common/timer.hpp

@@ -43,6 +43,8 @@
 
 namespace Thread {
 
+namespace Ip6 { class Ip6; }
+
 class Timer;
 
 /**
@@ -103,6 +105,14 @@ public:
      */
     void FireTimers(void);
 
+    /**
+     * This method returns the pointer to the parent Ip6 structure.
+     *
+     * @returns The pointer to the parent Ip6 structure.
+     *
+     */
+    Ip6::Ip6 *GetIp6();
+
 private:
     void SetAlarm(void);
 

src/core/mac/mac.cpp

@@ -51,6 +51,7 @@
 #include <platform/random.h>
 #include <thread/mle_router.hpp>
 #include <thread/thread_netif.hpp>
+#include <openthread-instance.h>
 
 namespace Thread {
 namespace Mac {
@@ -67,7 +68,6 @@ static const otExtAddress sMode2ExtAddress =
 
 static const uint8_t sExtendedPanidInit[] = {0xde, 0xad, 0x00, 0xbe, 0xef, 0x00, 0xca, 0xfe};
 static const char sNetworkNameInit[] = "OpenThread";
-static Mac *sMac;
 
 void Mac::StartCsmaBackoff(void)
 {
@@ -96,8 +96,6 @@ Mac::Mac(ThreadNetif &aThreadNetif):
     mWhitelist(),
     mBlacklist()
 {
-    sMac = this;
-
     mState = kStateIdle;
 
     mRxOnWhenIdle = false;
@@ -145,7 +143,7 @@ Mac::Mac(ThreadNetif &aThreadNetif):
     mPcapCallback = NULL;
     mPcapCallbackContext = NULL;
 
-    otPlatRadioEnable(NULL);
+    otPlatRadioEnable(mNetif.GetInstance());
 }
 
 ThreadError Mac::ActiveScan(uint32_t aScanChannels, uint16_t aScanDuration, ActiveScanHandler aHandler, void *aContext)
@@ -241,7 +239,7 @@ void Mac::HandleEnergyScanSampleRssi(void)
 
     VerifyOrExit(mState == kStateEnergyScan, ;);
 
-    rssi = otPlatRadioGetRssi(NULL);
+    rssi = otPlatRadioGetRssi(mNetif.GetInstance());
 
     if (rssi != kInvalidRssiValue)
     {
@@ -307,7 +305,7 @@ ThreadError Mac::SetExtAddress(const ExtAddress &aExtAddress)
         buf[i] = aExtAddress.m8[7 - i];
     }
 
-    SuccessOrExit(error = otPlatRadioSetExtendedAddress(NULL, buf));
+    SuccessOrExit(error = otPlatRadioSetExtendedAddress(mNetif.GetInstance(), buf));
     mExtAddress = aExtAddress;
 
 exit:
@@ -319,7 +317,7 @@ void Mac::GetHashMacAddress(ExtAddress *aHashMacAddress)
     Crypto::Sha256 sha256;
     uint8_t buf[Crypto::Sha256::kHashSize];
 
-    otPlatRadioGetIeeeEui64(NULL, buf);
+    otPlatRadioGetIeeeEui64(mNetif.GetInstance(), buf);
     sha256.Start();
     sha256.Update(buf, OT_EXT_ADDRESS_SIZE);
     sha256.Finish(buf);
@@ -336,7 +334,7 @@ ShortAddress Mac::GetShortAddress(void) const
 ThreadError Mac::SetShortAddress(ShortAddress aShortAddress)
 {
     mShortAddress = aShortAddress;
-    return otPlatRadioSetShortAddress(NULL, aShortAddress);
+    return otPlatRadioSetShortAddress(mNetif.GetInstance(), aShortAddress);
 }
 
 uint8_t Mac::GetChannel(void) const
@@ -392,7 +390,7 @@ PanId Mac::GetPanId(void) const
 ThreadError Mac::SetPanId(PanId aPanId)
 {
     mPanId = aPanId;
-    return otPlatRadioSetPanId(NULL, mPanId);
+    return otPlatRadioSetPanId(mNetif.GetInstance(), mPanId);
 }
 
 const uint8_t *Mac::GetExtendedPanId(void) const
@@ -439,17 +437,17 @@ void Mac::NextOperation(void)
     {
     case kStateActiveScan:
     case kStateEnergyScan:
-        otPlatRadioReceive(NULL, mScanChannel);
+        otPlatRadioReceive(mNetif.GetInstance(), mScanChannel);
         break;
 
     default:
-        if (mRxOnWhenIdle || mReceiveTimer.IsRunning() || otPlatRadioGetPromiscuous(NULL))
+        if (mRxOnWhenIdle || mReceiveTimer.IsRunning() || otPlatRadioGetPromiscuous(mNetif.GetInstance()))
         {
-            otPlatRadioReceive(NULL, mChannel);
+            otPlatRadioReceive(mNetif.GetInstance(), mChannel);
         }
         else
         {
-            otPlatRadioSleep(NULL);
+            otPlatRadioSleep(mNetif.GetInstance());
         }
 
         break;
@@ -628,7 +626,7 @@ exit:
 
 void Mac::HandleBeginTransmit(void)
 {
-    Frame &sendFrame(*static_cast<Frame *>(otPlatRadioGetTransmitBuffer(NULL)));
+    Frame &sendFrame(*static_cast<Frame *>(otPlatRadioGetTransmitBuffer(mNetif.GetInstance())));
     ThreadError error = kThreadError_None;
 
     sendFrame.SetPower(mMaxTransmitPower);
@@ -636,7 +634,7 @@ void Mac::HandleBeginTransmit(void)
     switch (mState)
     {
     case kStateActiveScan:
-        otPlatRadioSetPanId(NULL, kPanIdBroadcast);
+        otPlatRadioSetPanId(mNetif.GetInstance(), kPanIdBroadcast);
         sendFrame.SetChannel(mScanChannel);
         SendBeaconRequest(sendFrame);
         sendFrame.SetSequence(0);
@@ -667,12 +665,12 @@ void Mac::HandleBeginTransmit(void)
         sendFrame.SetPower(mMaxTransmitPower);
     }
 
-    error = otPlatRadioReceive(NULL, sendFrame.GetChannel());
+    error = otPlatRadioReceive(mNetif.GetInstance(), sendFrame.GetChannel());
     assert(error == kThreadError_None);
-    error = otPlatRadioTransmit(NULL);
+    error = otPlatRadioTransmit(mNetif.GetInstance());
     assert(error == kThreadError_None);
 
-    if (sendFrame.GetAckRequest() && !(otPlatRadioGetCaps(NULL) & kRadioCapsAckTimeout))
+    if (sendFrame.GetAckRequest() && !(otPlatRadioGetCaps(mNetif.GetInstance()) & kRadioCapsAckTimeout))
     {
         mMacTimer.Start(kAckTimeout);
         otLogDebgMac("ack timer start\n");
@@ -692,9 +690,9 @@ exit:
     }
 }
 
-extern "C" void otPlatRadioTransmitDone(otInstance *, bool aRxPending, ThreadError aError)
+extern "C" void otPlatRadioTransmitDone(otInstance *aInstance, bool aRxPending, ThreadError aError)
 {
-    sMac->TransmitDoneTask(aRxPending, aError);
+    aInstance->mThreadNetif.GetMac().TransmitDoneTask(aRxPending, aError);
 }
 
 void Mac::TransmitDoneTask(bool aRxPending, ThreadError aError)
@@ -747,7 +745,7 @@ void Mac::HandleMacTimer(void *aContext)
 
 void Mac::HandleMacTimer(void)
 {
-    otPlatRadioReceive(NULL, mChannel);
+    otPlatRadioReceive(mNetif.GetInstance(), mChannel);
 
     switch (mState)
     {
@@ -759,7 +757,7 @@ void Mac::HandleMacTimer(void)
 
             if (mScanChannels == 0 || mScanChannel > kPhyMaxChannel)
             {
-                otPlatRadioSetPanId(NULL, mPanId);
+                otPlatRadioSetPanId(mNetif.GetInstance(), mPanId);
                 mActiveScanHandler(mScanContext, NULL);
                 ScheduleNextTransmission();
                 ExitNow();
@@ -830,7 +828,7 @@ void Mac::HandleReceiveTimer(void)
 
 void Mac::SentFrame(ThreadError aError)
 {
-    Frame &sendFrame(*static_cast<Frame *>(otPlatRadioGetTransmitBuffer(NULL)));
+    Frame &sendFrame(*static_cast<Frame *>(otPlatRadioGetTransmitBuffer(mNetif.GetInstance())));
     Sender *sender;
 
     switch (aError)
@@ -1048,9 +1046,9 @@ exit:
     return error;
 }
 
-extern "C" void otPlatRadioReceiveDone(otInstance *, RadioPacket *aFrame, ThreadError aError)
+extern "C" void otPlatRadioReceiveDone(otInstance *aInstance, RadioPacket *aFrame, ThreadError aError)
 {
-    sMac->ReceiveDoneTask(static_cast<Frame *>(aFrame), aError);
+    aInstance->mThreadNetif.GetMac().ReceiveDoneTask(static_cast<Frame *>(aFrame), aError);
 }
 
 void Mac::ReceiveDoneTask(Frame *aFrame, ThreadError aError)
@@ -1298,12 +1296,12 @@ void Mac::SetPcapCallback(otLinkPcapCallback aPcapCallback, void *aCallbackConte
 
 bool Mac::IsPromiscuous(void)
 {
-    return otPlatRadioGetPromiscuous(NULL);
+    return otPlatRadioGetPromiscuous(mNetif.GetInstance());
 }
 
 void Mac::SetPromiscuous(bool aPromiscuous)
 {
-    otPlatRadioSetPromiscuous(NULL, aPromiscuous);
+    otPlatRadioSetPromiscuous(mNetif.GetInstance(), aPromiscuous);
 
     if (mState == kStateIdle)
     {
@@ -1328,7 +1326,7 @@ otMacCounters &Mac::GetCounters(void)
 
 void Mac::EnableSrcMatch(bool aEnable)
 {
-    otPlatRadioEnableSrcMatch(NULL, aEnable);
+    otPlatRadioEnableSrcMatch(mNetif.GetInstance(), aEnable);
     otLogDebgMac("Enable SrcMatch -- %d(0:Dis, 1:En)\n", aEnable);
 }
 
@@ -1338,7 +1336,7 @@ ThreadError Mac::AddSrcMatchEntry(Address &aAddr)
 
     if (aAddr.mLength == 2)
     {
-        error = otPlatRadioAddSrcMatchShortEntry(NULL, aAddr.mShortAddress);
+        error = otPlatRadioAddSrcMatchShortEntry(mNetif.GetInstance(), aAddr.mShortAddress);
         otLogDebgMac("Adding short address: 0x%x -- %d (0:Ok, 3:NoBufs)\n", aAddr.mShortAddress, error);
     }
     else
@@ -1350,7 +1348,7 @@ ThreadError Mac::AddSrcMatchEntry(Address &aAddr)
             buf[i] = aAddr.mExtAddress.m8[7 - i];
         }
 
-        error = otPlatRadioAddSrcMatchExtEntry(NULL, buf);
+        error = otPlatRadioAddSrcMatchExtEntry(mNetif.GetInstance(), buf);
         otLogDebgMac("Adding extended address: 0x%02x%02x%02x%02x%02x%02x%02x%02x -- %d (0:OK, 3:NoBufs)\n",
                      buf[7], buf[6], buf[5], buf[4], buf[3], buf[2], buf[1], buf[0], error);
     }
@@ -1364,7 +1362,7 @@ ThreadError Mac::ClearSrcMatchEntry(Address &aAddr)
 
     if (aAddr.mLength == 2)
     {
-        error = otPlatRadioClearSrcMatchShortEntry(NULL, aAddr.mShortAddress);
+        error = otPlatRadioClearSrcMatchShortEntry(mNetif.GetInstance(), aAddr.mShortAddress);
         otLogDebgMac("Clearing short address: 0x%x -- %d (0:OK, 10:NoAddress)\n", aAddr.mShortAddress, error);
     }
     else
@@ -1376,7 +1374,7 @@ ThreadError Mac::ClearSrcMatchEntry(Address &aAddr)
             buf[i] = aAddr.mExtAddress.m8[7 - i];
         }
 
-        error = otPlatRadioClearSrcMatchExtEntry(NULL, buf);
+        error = otPlatRadioClearSrcMatchExtEntry(mNetif.GetInstance(), buf);
         otLogDebgMac("Clearing extended address: 0x%02x%02x%02x%02x%02x%02x%02x%02x -- %d (0:OK, 10:NoAddress)\n",
                      buf[7], buf[6], buf[5], buf[4], buf[3], buf[2], buf[1], buf[0], error);
     }
@@ -1386,8 +1384,8 @@ ThreadError Mac::ClearSrcMatchEntry(Address &aAddr)
 
 void Mac::ClearSrcMatchEntries()
 {
-    otPlatRadioClearSrcMatchShortEntries(NULL);
-    otPlatRadioClearSrcMatchExtEntries(NULL);
+    otPlatRadioClearSrcMatchShortEntries(mNetif.GetInstance());
+    otPlatRadioClearSrcMatchExtEntries(mNetif.GetInstance());
     otLogDebgMac("Clearing source match table");
 }
 

src/core/net/ip6.cpp

@@ -43,6 +43,7 @@
 #include <net/netif.hpp>
 #include <net/udp6.hpp>
 #include <thread/mle.hpp>
+#include <openthread-instance.h>
 
 namespace Thread {
 namespace Ip6 {
@@ -831,5 +832,10 @@ exit:
     return rval;
 }
 
+otInstance *Ip6::GetInstance()
+{
+    return otInstanceFromIp6(this);
+}
+
 }  // namespace Ip6
 }  // namespace Thread

src/core/net/ip6.hpp

@@ -323,6 +323,14 @@ public:
      */
     int8_t GetOnLinkNetif(const Address &aAddress);
 
+    /**
+     * This method returns the pointer to the parent otInstance structure.
+     *
+     * @returns The pointer to the parent otInstance structure.
+     *
+     */
+    otInstance *GetInstance();
+
     Routes mRoutes;
     Icmp mIcmp;
     Udp mUdp;
@@ -357,6 +365,16 @@ private:
     int8_t mNextInterfaceId;
 };
 
+static inline Ip6 *Ip6FromTaskletScheduler(TaskletScheduler *aTaskletScheduler)
+{
+    return (Ip6 *)CONTAINING_RECORD(aTaskletScheduler, Ip6, mTaskletScheduler);
+}
+
+static inline Ip6 *Ip6FromTimerScheduler(TimerScheduler *aTimerScheduler)
+{
+    return (Ip6 *)CONTAINING_RECORD(aTimerScheduler, Ip6, mTimerScheduler);
+}
+
 /**
  * @}
  *

src/core/net/netif.hpp

@@ -427,9 +427,6 @@ private:
     NetifUnicastAddress mExtUnicastAddresses[OPENTHREAD_CONFIG_MAX_EXT_IP_ADDRS];
     uint8_t mMaskExtUnicastAddresses; // Must have enough bits to hold OPENTHREAD_CONFIG_MAX_EXT_IP_ADDRS
 
-    static Netif *sNetifListHead;
-    static int8_t sNextInterfaceId;
-
     /**
      * This method determines if an address is one of the external unicast addresses, and if so returns
      * the index in the mExtUnicastAddresses array.

src/core/openthread-instance.h

@@ -0,0 +1,92 @@
+/*
+ *  Copyright (c) 2016, The OpenThread Authors.
+ *  All rights reserved.
+ *
+ *  Redistribution and use in source and binary forms, with or without
+ *  modification, are permitted provided that the following conditions are met:
+ *  1. Redistributions of source code must retain the above copyright
+ *     notice, this list of conditions and the following disclaimer.
+ *  2. Redistributions in binary form must reproduce the above copyright
+ *     notice, this list of conditions and the following disclaimer in the
+ *     documentation and/or other materials provided with the distribution.
+ *  3. Neither the name of the copyright holder nor the
+ *     names of its contributors may be used to endorse or promote products
+ *     derived from this software without specific prior written permission.
+ *
+ *  THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
+ *  AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ *  IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ *  ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE
+ *  LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
+ *  CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
+ *  SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
+ *  INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
+ *  CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
+ *  ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+ *  POSSIBILITY OF SUCH DAMAGE.
+ */
+
+/**
+ * @file
+ * @brief
+ *  This file defines the structure of the variables required for all instances of OpenThread API.
+ */
+
+#ifndef OPENTHREADINSTANCE_H_
+#define OPENTHREADINSTANCE_H_
+
+#include <stdint.h>
+#include <stdbool.h>
+
+#include <openthread-types.h>
+#include <crypto/mbedtls.hpp>
+#include <net/ip6.hpp>
+#include <thread/thread_netif.hpp>
+
+/**
+ * This type represents all the static / global variables used by OpenThread allocated in one place.
+ */
+typedef struct otInstance
+{
+    //
+    // Callbacks
+    //
+
+    Thread::Ip6::NetifCallback mNetifCallback;
+
+    otReceiveIp6DatagramCallback mReceiveIp6DatagramCallback;
+    void *mReceiveIp6DatagramCallbackContext;
+
+    otHandleActiveScanResult mActiveScanCallback;
+    void *mActiveScanCallbackContext;
+
+    otHandleEnergyScanResult mEnergyScanCallback;
+    void *mEnergyScanCallbackContext;
+
+    otHandleActiveScanResult mDiscoverCallback;
+    void *mDiscoverCallbackContext;
+
+    //
+    // State
+    //
+
+    Thread::Crypto::MbedTls mMbedTls;
+    Thread::Ip6::Ip6 mIp6;
+    Thread::ThreadNetif mThreadNetif;
+
+    // Constructor
+    otInstance(void);
+
+} otInstance;
+
+static inline otInstance *otInstanceFromIp6(Thread::Ip6::Ip6 *aIp6)
+{
+    return (otInstance *)CONTAINING_RECORD(aIp6, otInstance, mIp6);
+}
+
+static inline otInstance *otInstanceFromThreadNetif(Thread::ThreadNetif *aThreadNetif)
+{
+    return (otInstance *)CONTAINING_RECORD(aThreadNetif, otInstance, mThreadNetif);
+}
+
+#endif  // OPENTHREADINSTANCE_H_

src/core/thread/address_resolver.cpp

@@ -175,7 +175,7 @@ ThreadError AddressResolver::SendAddressQuery(const Ip6::Address &aEid)
     Ip6::MessageInfo messageInfo;
 
     sockaddr.mPort = kCoapUdpPort;
-    mSocket.Open(&HandleUdpReceive, this);
+    mSocket.Open(&AddressResolver::HandleUdpReceive, this);
     mSocket.Bind(sockaddr);
 
     VerifyOrExit((message = mSocket.NewMessage(0)) != NULL, error = kThreadError_NoBufs);
@@ -350,7 +350,7 @@ ThreadError AddressResolver::SendAddressError(const ThreadTargetTlv &aTarget, co
     Ip6::SockAddr sockaddr;
 
     sockaddr.mPort = kCoapUdpPort;
-    mSocket.Open(&HandleUdpReceive, this);
+    mSocket.Open(&AddressResolver::HandleUdpReceive, this);
     mSocket.Bind(sockaddr);
 
     VerifyOrExit((message = mSocket.NewMessage(0)) != NULL, error = kThreadError_NoBufs);

src/core/thread/meshcop_dataset_manager.cpp

@@ -37,6 +37,8 @@
 #include <stdio.h>
 
 #include <openthread-types.h>
+#include <common/code_utils.hpp>
+#include <common/debug.hpp>
 #include <coap/coap_header.hpp>
 #include <common/debug.hpp>
 #include <common/code_utils.hpp>
@@ -753,7 +755,7 @@ ThreadError ActiveDataset::ApplyConfiguration(void)
 
 PendingDataset::PendingDataset(ThreadNetif &aThreadNetif):
     DatasetManager(aThreadNetif, Tlv::kPendingTimestamp, OPENTHREAD_URI_PENDING_SET, OPENTHREAD_URI_PENDING_GET),
-    mTimer(aThreadNetif.GetIp6().mTimerScheduler, HandleTimer, this)
+    mTimer(aThreadNetif.GetIp6().mTimerScheduler, PendingDataset::HandleTimer, this)
 {
 }
 

src/core/thread/mle.cpp

@@ -195,7 +195,7 @@ ThreadError Mle::Start(void)
     ThreadError error = kThreadError_None;
 
     // cannot bring up the interface if IEEE 802.15.4 promiscuous mode is enabled
-    VerifyOrExit(otPlatRadioGetPromiscuous(NULL) == false, error = kThreadError_Busy);
+    VerifyOrExit(otPlatRadioGetPromiscuous(mNetif.GetInstance()) == false, error = kThreadError_Busy);
     VerifyOrExit(mNetif.IsUp(), error = kThreadError_InvalidState);
 
     mDeviceState = kDeviceStateDetached;

src/core/thread/thread_netif.cpp

@@ -41,6 +41,7 @@
 #include <thread/thread_netif.hpp>
 #include <thread/thread_tlvs.hpp>
 #include <thread/thread_uris.hpp>
+#include <openthread-instance.h>
 
 using Thread::Encoding::BigEndian::HostSwap16;
 
@@ -151,4 +152,9 @@ ThreadError ThreadNetif::SendMessage(Message &message)
     return mMeshForwarder.SendMessage(message);
 }
 
+otInstance *ThreadNetif::GetInstance()
+{
+    return otInstanceFromThreadNetif(this);
+}
+
 }  // namespace Thread

src/core/thread/thread_netif.hpp

@@ -261,6 +261,14 @@ public:
     MeshCoP::Joiner &GetJoiner(void) { return mJoiner; }
 #endif  // OPENTHREAD_ENABLE_JOINER
 
+    /**
+     * This method returns the pointer to the parent otInstance structure.
+     *
+     * @returns The pointer to the parent otInstance structure.
+     *
+     */
+    otInstance *GetInstance();
+
 private:
     Coap::Server mCoapServer;
     AddressResolver mAddressResolver;

src/ncp/ncp_base.cpp

@@ -38,6 +38,7 @@
 #include <net/ip6.hpp>
 #include <openthread.h>
 #include <openthread-diag.h>
+#include <openthread-instance.h>
 #include <stdarg.h>
 #include <platform/radio.h>
 #include <platform/misc.h>
@@ -45,7 +46,6 @@
 namespace Thread
 {
 
-extern Ip6::Ip6 *sIp6;
 static NcpBase *sNcpContext = NULL;
 
 #define NCP_PLAT_RESET_REASON        (1U<<31)
@@ -415,7 +415,7 @@ static uint8_t BorderRouterConfigToFlagByte(const otBorderRouterConfig &config)
 
 NcpBase::NcpBase(otInstance *aInstance):
     mInstance(aInstance),
-    mUpdateChangedPropsTask(sIp6->mTaskletScheduler, &NcpBase::UpdateChangedProps, this)
+    mUpdateChangedPropsTask(aInstance->mIp6.mTaskletScheduler, &NcpBase::UpdateChangedProps, this)
 {
     assert(mInstance != NULL);
     mSupportedChannelMask = kPhySupportedChannelMask;

src/ncp/ncp_spi.cpp

@@ -37,6 +37,7 @@
 #include <ncp/ncp_spi.hpp>
 #include <platform/spi-slave.h>
 #include <core/openthread-core-config.h>
+#include <openthread-instance.h>
 
 #define SPI_RESET_FLAG          0x80
 #define SPI_CRC_FLAG            0x40
@@ -48,8 +49,6 @@ namespace Thread {
 static otDEFINE_ALIGNED_VAR(sNcpRaw, sizeof(NcpSpi), uint64_t);
 static NcpSpi *sNcpSpi;
 
-extern Ip6::Ip6 *sIp6;
-
 extern "C" void otNcpInit(otInstance *aInstance)
 {
     sNcpSpi = new(&sNcpRaw) NcpSpi(aInstance);
@@ -89,8 +88,8 @@ static uint16_t spi_header_get_data_len(const uint8_t *header)
 
 NcpSpi::NcpSpi(otInstance *aInstance):
     NcpBase(aInstance),
-    mHandleRxFrameTask(sIp6->mTaskletScheduler, &NcpSpi::HandleRxFrame, this),
-    mPrepareTxFrameTask(sIp6->mTaskletScheduler, &NcpSpi::PrepareTxFrame, this),
+    mHandleRxFrameTask(aInstance->mIp6.mTaskletScheduler, &NcpSpi::HandleRxFrame, this),
+    mPrepareTxFrameTask(aInstance->mIp6.mTaskletScheduler, &NcpSpi::PrepareTxFrame, this),
     mTxFrameBuffer(mTxBuffer, sizeof(mTxBuffer))
 {
     memset(mEmptySendFrame, 0, kSpiHeaderLength);

src/ncp/ncp_uart.cpp

@@ -46,14 +46,13 @@
 #include <platform/logging.h>
 #include <platform/uart.h>
 #include <core/openthread-core-config.h>
+#include <openthread-instance.h>
 
 namespace Thread {
 
 static otDEFINE_ALIGNED_VAR(sNcpRaw, sizeof(NcpUart), uint64_t);
 static NcpUart *sNcpUart;
 
-extern Ip6::Ip6 *sIp6;
-
 extern "C" void otNcpInit(otInstance *aInstance)
 {
     sNcpUart = new(&sNcpRaw) NcpUart(aInstance);
@@ -91,7 +90,7 @@ NcpUart::NcpUart(otInstance *aInstance):
     mFrameDecoder(mRxBuffer, sizeof(mRxBuffer), &NcpUart::HandleFrame, &NcpUart::HandleError, this),
     mUartBuffer(),
     mTxFrameBuffer(mTxBuffer, sizeof(mTxBuffer)),
-    mUartSendTask(sIp6->mTaskletScheduler, EncodeAndSendToUart, this)
+    mUartSendTask(aInstance->mIp6.mTaskletScheduler, EncodeAndSendToUart, this)
 {
     mState = kStartingFrame;
 

tests/unit/test_platform.cpp

@@ -65,11 +65,6 @@ extern "C" {
     {
     }
 
-    bool otAreTaskletsPending(otInstance *)
-    {
-        return false;
-    }
-
     //
     // Alarm
     //

tests/unit/test_timer.cpp

@@ -32,6 +32,7 @@
 #include <common/timer.hpp>
 #include <platform/alarm.h>
 #include <string.h>
+#include <openthread-instance.h>
 
 enum
 {
@@ -42,7 +43,6 @@ enum
     kCallCountIndexMax
 };
 
-static Thread::TimerScheduler sTimerScheduler;
 extern uint32_t sNow;
 extern uint32_t sPlatT0;
 extern uint32_t sPlatDt;
@@ -71,7 +71,8 @@ int TestOneTimer(void)
 {
     const uint32_t kTimeT0 = 1000;
     const uint32_t kTimerInterval = 10;
-    Thread::Timer timer(sTimerScheduler, TestTimerHandler, NULL);
+    otInstance aInstance;
+    Thread::Timer timer(aInstance.mIp6.mTimerScheduler, TestTimerHandler, NULL);
 
     // Test one Timer basic operation.
 
@@ -89,7 +90,7 @@ int TestOneTimer(void)
 
     sNow += kTimerInterval;
 
-    otPlatAlarmFired(NULL);
+    otPlatAlarmFired(&aInstance);
 
     VerifyOrQuit(sCallCount[kCallCountIndexAlarmStart]    == 1, "TestOneTimer: Start CallCount Failed.\n");
     VerifyOrQuit(sCallCount[kCallCountIndexAlarmStop]     == 1, "TestOneTimer: Stop CallCount Failed.\n");
@@ -113,7 +114,7 @@ int TestOneTimer(void)
 
     sNow += kTimerInterval;
 
-    otPlatAlarmFired(NULL);
+    otPlatAlarmFired(&aInstance);
 
     VerifyOrQuit(sCallCount[kCallCountIndexAlarmStart]    == 1, "TestOneTimer: Start CallCount Failed.\n");
     VerifyOrQuit(sCallCount[kCallCountIndexAlarmStop]     == 1, "TestOneTimer: Stop CallCount Failed.\n");
@@ -137,7 +138,7 @@ int TestOneTimer(void)
 
     sNow += kTimerInterval + 5;
 
-    otPlatAlarmFired(NULL);
+    otPlatAlarmFired(&aInstance);
 
     VerifyOrQuit(sCallCount[kCallCountIndexAlarmStart]    == 1, "TestOneTimer: Start CallCount Failed.\n");
     VerifyOrQuit(sCallCount[kCallCountIndexAlarmStop]     == 1, "TestOneTimer: Stop CallCount Failed.\n");
@@ -161,7 +162,7 @@ int TestOneTimer(void)
 
     sNow += kTimerInterval - 2;
 
-    otPlatAlarmFired(NULL);
+    otPlatAlarmFired(&aInstance);
 
     VerifyOrQuit(sCallCount[kCallCountIndexAlarmStart]    == 2, "TestOneTimer: Start CallCount Failed.\n");
     VerifyOrQuit(sCallCount[kCallCountIndexAlarmStop]     == 0, "TestOneTimer: Stop CallCount Failed.\n");
@@ -171,7 +172,7 @@ int TestOneTimer(void)
 
     sNow += kTimerInterval;
 
-    otPlatAlarmFired(NULL);
+    otPlatAlarmFired(&aInstance);
 
     VerifyOrQuit(sCallCount[kCallCountIndexAlarmStart]    == 2, "TestOneTimer: Start CallCount Failed.\n");
     VerifyOrQuit(sCallCount[kCallCountIndexAlarmStop]     == 1, "TestOneTimer: Stop CallCount Failed.\n");
@@ -302,17 +303,19 @@ int TestTenTimers(void)
         11
     };
 
+    otInstance aInstance;
+
     uint32_t timerContextHandleCounter[kNumTimers] = {0};
-    Thread::Timer timer0(sTimerScheduler, TestTimerHandler, &timerContextHandleCounter[0]);
-    Thread::Timer timer1(sTimerScheduler, TestTimerHandler, &timerContextHandleCounter[1]);
-    Thread::Timer timer2(sTimerScheduler, TestTimerHandler, &timerContextHandleCounter[2]);
-    Thread::Timer timer3(sTimerScheduler, TestTimerHandler, &timerContextHandleCounter[3]);
-    Thread::Timer timer4(sTimerScheduler, TestTimerHandler, &timerContextHandleCounter[4]);
-    Thread::Timer timer5(sTimerScheduler, TestTimerHandler, &timerContextHandleCounter[5]);
-    Thread::Timer timer6(sTimerScheduler, TestTimerHandler, &timerContextHandleCounter[6]);
-    Thread::Timer timer7(sTimerScheduler, TestTimerHandler, &timerContextHandleCounter[7]);
-    Thread::Timer timer8(sTimerScheduler, TestTimerHandler, &timerContextHandleCounter[8]);
-    Thread::Timer timer9(sTimerScheduler, TestTimerHandler, &timerContextHandleCounter[9]);
+    Thread::Timer timer0(aInstance.mIp6.mTimerScheduler, TestTimerHandler, &timerContextHandleCounter[0]);
+    Thread::Timer timer1(aInstance.mIp6.mTimerScheduler, TestTimerHandler, &timerContextHandleCounter[1]);
+    Thread::Timer timer2(aInstance.mIp6.mTimerScheduler, TestTimerHandler, &timerContextHandleCounter[2]);
+    Thread::Timer timer3(aInstance.mIp6.mTimerScheduler, TestTimerHandler, &timerContextHandleCounter[3]);
+    Thread::Timer timer4(aInstance.mIp6.mTimerScheduler, TestTimerHandler, &timerContextHandleCounter[4]);
+    Thread::Timer timer5(aInstance.mIp6.mTimerScheduler, TestTimerHandler, &timerContextHandleCounter[5]);
+    Thread::Timer timer6(aInstance.mIp6.mTimerScheduler, TestTimerHandler, &timerContextHandleCounter[6]);
+    Thread::Timer timer7(aInstance.mIp6.mTimerScheduler, TestTimerHandler, &timerContextHandleCounter[7]);
+    Thread::Timer timer8(aInstance.mIp6.mTimerScheduler, TestTimerHandler, &timerContextHandleCounter[8]);
+    Thread::Timer timer9(aInstance.mIp6.mTimerScheduler, TestTimerHandler, &timerContextHandleCounter[9]);
     Thread::Timer *timers[kNumTimers] = {&timer0, &timer1, &timer2, &timer3, &timer4, &timer5, &timer6, &timer7, &timer8, &timer9};
     size_t i;
 
@@ -353,7 +356,7 @@ int TestTenTimers(void)
             // timer is ready to be triggered by examining the aDt arg passed into otPlatAlarmStartAt().  If
             // that value is 0, then otPlatAlarmFired should be fired immediately. This loop calls otPlatAlarmFired()
             // the requisite number of times based on the aDt argument.
-            otPlatAlarmFired(NULL);
+            otPlatAlarmFired(&aInstance);
         }
         while (sPlatDt == 0);