Remove Netif name and rely on enumerated Interface Id's for netif. (#833)

* Remove Netif name and rely on enumerated Interface Id's for netif.

include/openthread-types.h

@@ -843,6 +843,14 @@ typedef struct otNetifAddress
     struct otNetifAddress *mNext;               ///< A pointer to the next network interface address.
 } otNetifAddress;
 
+/**
+ * This enumeration represents the list of allowable values for an InterfaceId.
+ */
+typedef enum otNetifInterfaceId
+{
+    OT_NETIF_INTERFACE_ID_THREAD = 1,  ///< The Thread Network interface ID.
+} otNetifInterfaceId;
+
 /**
  * This structure represents data used by Semantically Opaque IID Generator.
  *

src/cli/cli.cpp

@@ -1107,7 +1107,7 @@ void Interpreter::ProcessPing(int argc, char *argv[])
 
     memset(&sMessageInfo, 0, sizeof(sMessageInfo));
     SuccessOrExit(error = sMessageInfo.GetPeerAddr().FromString(argv[0]));
-    sMessageInfo.mInterfaceId = 1;
+    sMessageInfo.mInterfaceId = OT_NETIF_INTERFACE_ID_THREAD;
 
     sLength = 8;
     sCount = 1;

src/core/meshcop/joiner.cpp

@@ -227,7 +227,7 @@ void Joiner::HandleUdpTransmit(void)
     messageInfo.GetPeerAddr().mFields.m16[0] = HostSwap16(0xfe80);
     messageInfo.GetPeerAddr().SetIid(mJoinerRouter);
     messageInfo.mPeerPort = mJoinerUdpPort;
-    messageInfo.mInterfaceId = 1;
+    messageInfo.mInterfaceId = OT_NETIF_INTERFACE_ID_THREAD;
 
     SuccessOrExit(error = mSocket.SendTo(*mTransmitMessage, messageInfo));
 

src/core/net/ip6.cpp

@@ -58,8 +58,7 @@ Ip6::Ip6(void):
     mReceiveIp6DatagramCallback(NULL),
     mReceiveIp6DatagramCallbackContext(NULL),
     mIsReceiveIp6FilterEnabled(false),
-    mNetifListHead(NULL),
-    mNextInterfaceId(1)
+    mNetifListHead(NULL)
 {
 }
 
@@ -609,7 +608,7 @@ ThreadError Ip6::AddNetif(Netif &aNetif)
 
         do
         {
-            if (netif == &aNetif)
+            if (netif == &aNetif || netif->mInterfaceId == aNetif.mInterfaceId)
             {
                 ExitNow(error = kThreadError_Already);
             }
@@ -621,11 +620,6 @@ ThreadError Ip6::AddNetif(Netif &aNetif)
 
     aNetif.mNext = NULL;
 
-    if (aNetif.mInterfaceId < 0)
-    {
-        aNetif.mInterfaceId = mNextInterfaceId++;
-    }
-
 exit:
     return error;
 }
@@ -682,22 +676,6 @@ exit:
     return netif;
 }
 
-Netif *Ip6::GetNetifByName(char *aName)
-{
-    Netif *netif;
-
-    for (netif = mNetifListHead; netif; netif = netif->mNext)
-    {
-        if (strcmp(netif->GetName(), aName) == 0)
-        {
-            ExitNow();
-        }
-    }
-
-exit:
-    return netif;
-}
-
 bool Ip6::IsUnicastAddress(const Address &aAddress)
 {
     bool rval = false;

src/core/net/ip6.hpp

@@ -282,16 +282,6 @@ public:
      */
     Netif *GetNetifById(int8_t aInterfaceId);
 
-    /**
-     * This method returns the network interface identified by @p aName.
-     *
-     * @param[in]  aName  A pointer to a NULL-terminated string.
-     *
-     * @returns A pointer to the network interface or NULL if none is found.
-     *
-     */
-    Netif *GetNetifByName(char *aName);
-
     /**
      * This method indicates whether or not @p aAddress is assigned to a network interface.
      *
@@ -363,7 +353,6 @@ private:
     bool mIsReceiveIp6FilterEnabled;
 
     Netif *mNetifListHead;
-    int8_t mNextInterfaceId;
 };
 
 static inline Ip6 *Ip6FromTaskletScheduler(TaskletScheduler *aTaskletScheduler)

src/core/net/netif.cpp

@@ -40,14 +40,14 @@
 namespace Thread {
 namespace Ip6 {
 
-Netif::Netif(Ip6 &aIp6):
+Netif::Netif(Ip6 &aIp6, int8_t aInterfaceId):
     mIp6(aIp6),
     mStateChangedTask(aIp6.mTaskletScheduler, &Netif::HandleStateChangedTask, this)
 {
     mCallbacks = NULL;
     mUnicastAddresses = NULL;
     mMulticastAddresses = NULL;
-    mInterfaceId = -1;
+    mInterfaceId = aInterfaceId;
     mAllRoutersSubscribed = false;
     mNext = NULL;
     mMaskExtUnicastAddresses = 0;

src/core/net/netif.hpp

@@ -233,10 +233,11 @@ public:
     /**
      * This constructor initializes the network interface.
      *
-     * @param[in]  aIp6  A reference to the IPv6 network object.
+     * @param[in]  aIp6             A reference to the IPv6 network object.
+     * @param[in]  aInterfaceId     The interface ID for this object.
      *
      */
-    Netif(Ip6 &aIp6);
+    Netif(Ip6 &aIp6, int8_t aInterfaceId);
 
     /**
      * This method returns a reference to the IPv6 network object.
@@ -418,14 +419,6 @@ public:
      */
     virtual ThreadError SendMessage(Message &aMessage) = 0;
 
-    /**
-     * This virtual method returns a NULL-terminated string that names the network interface.
-     *
-     * @returns A NULL-terminated string that names the network interface.
-     *
-     */
-    virtual const char *GetName(void) const = 0;
-
     /**
      * This virtual method fills out @p aAddress with the link address.
      *

src/core/thread/thread_netif.cpp

@@ -53,10 +53,8 @@ static const uint8_t kThreadMasterKey[] =
     0x88, 0x99, 0xaa, 0xbb, 0xcc, 0xdd, 0xee, 0xff,
 };
 
-static const char name[] = "thread";
-
 ThreadNetif::ThreadNetif(Ip6::Ip6 &aIp6):
-    Netif(aIp6),
+    Netif(aIp6, OT_NETIF_INTERFACE_ID_THREAD),
     mCoapServer(aIp6.mUdp, kCoapUdpPort),
     mCoapClient(*this),
     mAddressResolver(*this),
@@ -88,11 +86,6 @@ ThreadNetif::ThreadNetif(Ip6::Ip6 &aIp6):
     mKeyManager.SetMasterKey(kThreadMasterKey, sizeof(kThreadMasterKey));
 }
 
-const char *ThreadNetif::GetName(void) const
-{
-    return name;
-}
-
 ThreadError ThreadNetif::Up(void)
 {
     if (!mIsUp)

src/core/thread/thread_netif.hpp

@@ -116,14 +116,6 @@ public:
      */
     bool IsUp(void) const;
 
-    /**
-     * This method returns a pointer to a NULL-terminated string that names the interface.
-     *
-     * @returns A pointer to a NULL-terminated string that names the interface.
-     *
-     */
-    const char *GetName(void) const;
-
     /**
      * This method retrieves the link address.
      *