Jira 913 BLESubscribed, BLEUnsubscribed Event Handlers are not called

1. Implement the subscribe changed event notify feature.
2. Fix unsubscribe return wrong value

Changed files:
  BLECallbacks.cpp - Add subscribe changed handler and disconnect process
  BLECallbacks.h - Callback declaration
  BLECharacteristicImp.cpp - Add the event changed handler
  BLECharacteristicImp.h - Handler declaration

Author: sgbihu

Diff for: libraries/CurieBLE/src/internal/BLECallbacks.cpp

@@ -27,6 +27,11 @@
 #include "BLEDeviceManager.h"
 #include "BLEProfileManager.h"
 
+#include "BLECallbacks.h"
+
+#include <atomic.h>
+#include "../src/services/ble/conn_internal.h"
+
 // GATT Server Only
 ssize_t profile_read_process(bt_conn_t *conn,
                              const bt_gatt_attr_t *attr,
@@ -237,6 +242,60 @@ void bleConnectEventHandler(bt_conn_t *conn,
     p->handleConnectEvent(conn, err);
 }
 
+static uint8_t ble_gatt_disconnected_cb(const struct bt_gatt_attr *attr, void *user_data)
+{
+    struct bt_conn *conn = (struct bt_conn *)user_data;
+    struct _bt_gatt_ccc *ccc;
+    size_t i;
+    
+    /* Check attribute user_data must be of type struct _bt_gatt_ccc */
+    if (attr->write != profile_gatt_attr_write_ccc) {
+        return BT_GATT_ITER_CONTINUE;
+    }
+    
+    ccc = (struct _bt_gatt_ccc *)attr->user_data;
+    /* If already disabled skip */
+    if (!ccc->value) {
+        return BT_GATT_ITER_CONTINUE;
+    }
+
+    for (i = 0; i < ccc->cfg_len; i++)
+    {
+        /* Ignore configurations with disabled value */
+        if (!ccc->cfg[i].value)
+        {
+            continue;
+        }
+
+        if (bt_addr_le_cmp(&conn->le.dst, &ccc->cfg[i].peer))
+        {
+            struct bt_conn *tmp;
+
+            /* Skip if there is another peer connected */
+            tmp = bt_conn_lookup_addr_le(&ccc->cfg[i].peer);
+            if (tmp) {
+                if (tmp->state == BT_CONN_CONNECTED) {
+                    bt_conn_unref(tmp);
+                    return BT_GATT_ITER_CONTINUE;
+                }
+
+                bt_conn_unref(tmp);
+            }
+        }
+    }
+
+    /* Reset value while disconnected */
+    memset(&ccc->value, 0, sizeof(ccc->value));
+
+    if (ccc->cfg_changed) {
+        ccc->cfg_changed(ccc->value);
+    }
+
+    pr_debug(LOG_MODULE_BLE, "ccc %p reseted", ccc);
+
+    return BT_GATT_ITER_CONTINUE;
+}
+
 
 void bleDisconnectEventHandler(bt_conn_t *conn, 
                                 uint8_t reason, 
@@ -245,6 +304,7 @@ void bleDisconnectEventHandler(bt_conn_t *conn,
     BLEDeviceManager* p = (BLEDeviceManager*)param;
 
     pr_info(LOG_MODULE_BLE, "Connect lost. Reason: %d", reason);
+    bt_gatt_foreach_attr(0x0001, 0xffff, ble_gatt_disconnected_cb, conn);
 
     p->handleDisconnectEvent(conn, reason);
 }
@@ -283,3 +343,29 @@ void ble_on_write_no_rsp_complete(struct bt_conn *conn, uint8_t err,
     BLECharacteristicImp::writeResponseReceived(conn, err, data);
 }
 
+ssize_t profile_gatt_attr_write_ccc(struct bt_conn *conn,
+                                    const struct bt_gatt_attr *attr, 
+                                    const void *buf,
+                                    uint16_t len, 
+                                    uint16_t offset)
+{
+    struct _bt_gatt_ccc *ccc = (struct _bt_gatt_ccc *)attr->user_data;
+    const uint16_t *data = (const uint16_t *)buf;
+    bool cccdChanged = (ccc->value != *data);
+    ssize_t retValue = bt_gatt_attr_write_ccc(conn, attr, buf, len, offset);
+    if (cccdChanged)
+    {
+        // Find characteristic and do notification
+        const struct bt_gatt_attr *attrChrc = attr - 1;
+        BLEAttribute *bleattr = (BLEAttribute *)attrChrc->user_data;
+        BLEAttributeType type = bleattr->type();
+        pr_debug(LOG_MODULE_BLE, "The Attribute type:%d", type);
+        if (BLETypeCharacteristic == type)
+        {
+            BLECharacteristicImp *blecharacteritic = (BLECharacteristicImp*)bleattr;
+            blecharacteritic->cccdValueChanged();
+        }
+    }
+    return retValue;
+}
+

Diff for: libraries/CurieBLE/src/internal/BLECallbacks.h

@@ -89,5 +89,11 @@ uint8_t profile_characteristic_read_rsp_process(bt_conn_t *conn,
                                                  const void *data, 
                                                  uint16_t length);
 
+ssize_t profile_gatt_attr_write_ccc(struct bt_conn *conn,
+                                    const struct bt_gatt_attr *attr, 
+                                    const void *buf,
+                                    uint16_t len, 
+                                    uint16_t offset);
+
 #endif
 

Diff for: libraries/CurieBLE/src/internal/BLECharacteristicImp.cpp

@@ -433,11 +433,13 @@ bool BLECharacteristicImp::unsubscribe(void)
     // Enable CCCD to allow peripheral send Notification/Indication
     retval = bt_gatt_unsubscribe(conn, &_sub_params);
     bt_conn_unref(conn);
-    if (0 == retval)
+    if (0 != retval)
     {
-        _subscribed = false;
+        return false;
     }
-    return _subscribed;
+    
+    _subscribed = false;
+    return true;
 }
 
 bool BLECharacteristicImp::subscribe(void)
@@ -802,7 +804,7 @@ int BLECharacteristicImp::updateProfile(bt_gatt_attr_t *attr_start, int& index)
         start->uuid = this->getClientCharacteristicConfigUuid();
         start->perm = BT_GATT_PERM_READ | BT_GATT_PERM_WRITE;
         start->read = bt_gatt_attr_read_ccc;
-        start->write = bt_gatt_attr_write_ccc;
+        start->write = profile_gatt_attr_write_ccc;
         start->user_data = this->getCccCfg();
 
         pr_info(LOG_MODULE_BLE, "cccd-%p", start);
@@ -1070,4 +1072,26 @@ uint8_t BLECharacteristicImp::discoverResponseProc(bt_conn_t *conn,
     return retVal;
 }
 
+void BLECharacteristicImp::cccdValueChanged()
+{
+    
+    enum BLECharacteristicEvent event = BLEUnsubscribed;
+    if (subscribed())
+    {
+        event = BLESubscribed;
+    }
+
+    if (_event_handlers[event]) 
+    {
+        BLECharacteristic chrcTmp(this, &_ble_device);
+        _event_handlers[event](_ble_device, chrcTmp);
+    }
+
+    if (_oldevent_handlers[event]) 
+    {
+        BLECharacteristic chrcTmp(this, &_ble_device);
+        BLECentral central(_ble_device);
+        _oldevent_handlers[event](central, chrcTmp);
+    }
+}
 

Diff for: libraries/CurieBLE/src/internal/BLECharacteristicImp.h

@@ -172,7 +172,7 @@ class BLECharacteristicImp: public BLEAttribute{
     static void writeResponseReceived(struct bt_conn *conn, 
                                       uint8_t err,
                                       const void *data);
-
+    void cccdValueChanged();
     int descriptorCount() const;
     uint8_t discoverResponseProc(bt_conn_t *conn,
                                  const bt_gatt_attr_t *attr,