Add API to read Thread EUI-64

Previously get_mac_address on a ThreadInterface returned the EUI-64
reported by the radio driver. This was required for commissioning, but
was inconsistent with other interfaces, and the API concept.

5.9.0 inadvertently changed this so that get_mac_address returned the
actual MAC address used by the radio, which is a hash result of the
EUI-64 for Thread.

The original "return the EUI-64" form was somewhat faulty, as
get_mac_address would not return the EUI-64 set by set_device_eui64() or
another mechanism before connect() was called.

Rather than revert to old behaviour, add a new API to get the device
EUI-64 to ThreadInterface, alongside the existing set API.

features/nanostack/mbed-mesh-api/mbed-mesh-api/ThreadInterface.h

@@ -30,12 +30,12 @@ public:
      *
      *  Must initialize to initialize the mesh on a phy.
      */
-    ThreadInterface() : user_set_eui64(false) { }
+    ThreadInterface() { }
 
     /** Create an initialized ThreadInterface
      *
      */
-    ThreadInterface(NanostackRfPhy *phy) : MeshInterfaceNanostack(phy), user_set_eui64(false) { }
+    ThreadInterface(NanostackRfPhy *phy) : MeshInterfaceNanostack(phy) { }
 
     /**
      * \brief Sets the eui64 for the device configuration.
@@ -44,6 +44,13 @@ public:
      * */
     void device_eui64_set(const uint8_t *eui64);
 
+    /**
+     * \brief Reads the eui64 from the device configuration.
+     * By default this value is read from the radio driver, but it may have
+     * been set by device_eui64_set().
+     * */
+    void device_eui64_get(uint8_t *eui64);
+
     /**
      * \brief sets the PSKd for the device configuration.
      * The default value is overwritten, which is defined in the mbed_lib.json file in the mesh-api
@@ -59,9 +66,6 @@ public:
     virtual int disconnect();
 protected:
     Nanostack::ThreadInterface *get_interface() const;
-
-private:
-    bool user_set_eui64;
 };
 
 #endif // THREADINTERFACE_H

features/nanostack/mbed-mesh-api/source/ThreadInterface.cpp

@@ -18,7 +18,7 @@ public:
     friend Nanostack;
     friend class ::ThreadInterface;
 private:
-    ThreadInterface(NanostackRfPhy &phy) : MeshInterface(phy), user_eui64_set(false) { }
+    ThreadInterface(NanostackRfPhy &phy) : MeshInterface(phy), eui64_set(false) { }
 
     /*
      * \brief Initialization of the interface.
@@ -52,6 +52,11 @@ private:
      * */
     void device_eui64_set(const uint8_t *eui64);
 
+    /**
+     * \brief Reads the eui64 from the device configuration.
+     * */
+    void device_eui64_get(uint8_t *eui64);
+
     /**
      * \brief sets the PSKd for the device configuration.
      * The default value is overwritten, which is defined in the mbed_lib.json file in the mesh-api
@@ -63,7 +68,7 @@ private:
 
     mesh_error_t device_pskd_set(const char *pskd);
 
-    bool user_eui64_set;
+    bool eui64_set;
 };
 
 Nanostack::ThreadInterface *ThreadInterface::get_interface() const
@@ -161,11 +166,7 @@ mesh_error_t Nanostack::ThreadInterface::init()
 {
     thread_tasklet_init();
     __mesh_handler_set_callback(this);
-    if (!user_eui64_set) {
-        uint8_t eui64[8];
-        get_phy().get_mac_address(eui64);
-        thread_tasklet_device_eui64_set(eui64);
-    }
+    device_eui64_get(NULL); // Ensure we've selected the EUI-64 - this does it
     interface_id = thread_tasklet_network_init(_device_id);
 
     if (interface_id == -2) {
@@ -216,12 +217,30 @@ void ThreadInterface::device_eui64_set(const uint8_t *eui64)
     get_interface()->device_eui64_set(eui64);
 }
 
+void ThreadInterface::device_eui64_get(uint8_t *eui64)
+{
+    get_interface()->device_eui64_get(eui64);
+}
+
 void Nanostack::ThreadInterface::device_eui64_set(const uint8_t *eui64)
 {
-    user_eui64_set = true;
+    eui64_set = true;
     thread_tasklet_device_eui64_set(eui64);
 }
 
+void Nanostack::ThreadInterface::device_eui64_get(uint8_t *eui64)
+{
+    if (!eui64_set) {
+        uint8_t eui64_buf[8];
+        get_phy().get_mac_address(eui64_buf);
+        device_eui64_set(eui64_buf);
+    }
+
+    if (eui64) {
+        thread_tasklet_device_eui64_get(eui64);
+    }
+}
+
 mesh_error_t ThreadInterface::device_pskd_set(const char *pskd)
 {
     return get_interface()->device_pskd_set(pskd);

features/nanostack/mbed-mesh-api/source/include/thread_tasklet.h

@@ -59,10 +59,15 @@ int8_t thread_tasklet_network_init(int8_t device_id);
 /*
  * \brief Sets eui64 for the device configuration
  * \param eui64 eui64 to be set
- * \param pskd private shared key
  */
 void thread_tasklet_device_eui64_set(const uint8_t *eui64);
 
+/*
+ * \brief Gets eui64 from the device configuration
+ * \param eui64 buffer for output eui64
+ */
+void thread_tasklet_device_eui64_get(uint8_t *eui64);
+
 /*
  * \brief Sets PSKd for the device configuration
  * \param pskd private shared key to be set

features/nanostack/mbed-mesh-api/source/thread_tasklet.c

@@ -474,6 +474,11 @@ void thread_tasklet_device_eui64_set(const uint8_t *eui64)
     memcpy(device_configuration.eui64, eui64, 8);
 }
 
+void thread_tasklet_device_eui64_get(uint8_t *eui64)
+{
+    memcpy(eui64, device_configuration.eui64, 8);
+}
+
 uint8_t thread_tasklet_device_pskd_set(const char *pskd)
 {
     int len = strlen(pskd);