Diff: microbit/microbit-dal/nRF51822/source/nRF5xServiceDiscovery.cpp

Revision:

0:b9164b348919

--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/microbit/microbit-dal/nRF51822/source/nRF5xServiceDiscovery.cpp	Mon Oct 17 12:41:20 2016 +0000
@@ -0,0 +1,310 @@
+/* mbed Microcontroller Library
+ * Copyright (c) 2006-2013 ARM Limited
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#include "nRF5xServiceDiscovery.h"
+
+ble_error_t
+nRF5xServiceDiscovery::launchCharacteristicDiscovery(Gap::Handle_t connectionHandle,
+                                                     Gap::Handle_t startHandle,
+                                                     Gap::Handle_t endHandle)
+{
+    characteristicDiscoveryStarted(connectionHandle);
+
+    ble_gattc_handle_range_t handleRange = {
+        .start_handle = startHandle,
+        .end_handle   = endHandle
+    };
+    uint32_t rc = sd_ble_gattc_characteristics_discover(connectionHandle, &handleRange);
+    ble_error_t err = BLE_ERROR_NONE;
+
+    switch (rc) {
+        case NRF_SUCCESS:
+            err = BLE_ERROR_NONE;
+            break;
+        case BLE_ERROR_INVALID_CONN_HANDLE:
+        case NRF_ERROR_INVALID_ADDR:
+            err = BLE_ERROR_INVALID_PARAM;
+            break;
+        case NRF_ERROR_BUSY:
+            err = BLE_STACK_BUSY;
+            break;
+        case NRF_ERROR_INVALID_STATE:
+            err = BLE_ERROR_INVALID_STATE;
+            break;
+        default:
+            err = BLE_ERROR_UNSPECIFIED;
+            break;
+    }
+
+    if (err) {
+        terminateCharacteristicDiscovery(err);
+    }
+    return err;
+}
+
+void
+nRF5xServiceDiscovery::setupDiscoveredServices(const ble_gattc_evt_prim_srvc_disc_rsp_t *response)
+{
+    serviceIndex = 0;
+    numServices  = response->count;
+
+    /* Account for the limitation on the number of discovered services we can handle at a time. */
+    if (numServices > BLE_DB_DISCOVERY_MAX_SRV) {
+        numServices = BLE_DB_DISCOVERY_MAX_SRV;
+    }
+
+    serviceUUIDDiscoveryQueue.reset();
+    for (unsigned serviceIndex = 0; serviceIndex < numServices; serviceIndex++) {
+        if (response->services[serviceIndex].uuid.type == BLE_UUID_TYPE_UNKNOWN) {
+            serviceUUIDDiscoveryQueue.enqueue(serviceIndex);
+            services[serviceIndex].setup(response->services[serviceIndex].handle_range.start_handle,
+                                         response->services[serviceIndex].handle_range.end_handle);
+        } else {
+            services[serviceIndex].setup(response->services[serviceIndex].uuid.uuid,
+                                         response->services[serviceIndex].handle_range.start_handle,
+                                         response->services[serviceIndex].handle_range.end_handle);
+        }
+    }
+
+    /* Trigger discovery of service UUID if necessary. */
+    if (serviceUUIDDiscoveryQueue.getCount()) {
+        serviceUUIDDiscoveryQueue.triggerFirst();
+    }
+}
+
+void
+nRF5xServiceDiscovery::setupDiscoveredCharacteristics(const ble_gattc_evt_char_disc_rsp_t *response)
+{
+    numCharacteristics  = response->count;
+
+    /* Account for the limitation on the number of discovered characteristics we can handle at a time. */
+    if (numCharacteristics > BLE_DB_DISCOVERY_MAX_CHAR_PER_SRV) {
+        numCharacteristics = BLE_DB_DISCOVERY_MAX_CHAR_PER_SRV;
+    }
+
+    charUUIDDiscoveryQueue.reset();
+    for (unsigned charIndex = 0; charIndex < numCharacteristics; charIndex++) {
+        if (response->chars[charIndex].uuid.type == BLE_UUID_TYPE_UNKNOWN) {
+            charUUIDDiscoveryQueue.enqueue(charIndex);
+            characteristics[charIndex].setup(gattc,
+                                             connHandle,
+                                             response->chars[charIndex].char_props,
+                                             response->chars[charIndex].handle_decl,
+                                             response->chars[charIndex].handle_value);
+        } else {
+            characteristics[charIndex].setup(gattc,
+                                             connHandle,
+                                             response->chars[charIndex].uuid.uuid,
+                                             response->chars[charIndex].char_props,
+                                             response->chars[charIndex].handle_decl,
+                                             response->chars[charIndex].handle_value);
+        }
+    }
+
+    /* Trigger discovery of char UUID if necessary. */
+    if (charUUIDDiscoveryQueue.getCount()) {
+        charUUIDDiscoveryQueue.triggerFirst();
+    }
+}
+
+void
+nRF5xServiceDiscovery::progressCharacteristicDiscovery(void)
+{
+    if (state != CHARACTERISTIC_DISCOVERY_ACTIVE) {
+        return;
+    }
+
+    if ((discoveredCharacteristic != nRF5xDiscoveredCharacteristic()) && (numCharacteristics > 0)) {
+        discoveredCharacteristic.setLastHandle(characteristics[0].getDeclHandle() - 1);
+
+        if ((matchingCharacteristicUUID == UUID::ShortUUIDBytes_t(BLE_UUID_UNKNOWN)) ||
+            ((matchingCharacteristicUUID == discoveredCharacteristic.getUUID()) &&
+             (matchingServiceUUID != UUID::ShortUUIDBytes_t(BLE_UUID_UNKNOWN)))) {
+            if (characteristicCallback) {
+                characteristicCallback(&discoveredCharacteristic);
+            }
+        }
+    }
+
+    for (uint8_t i = 0; i < numCharacteristics; ++i) {
+        if (state != CHARACTERISTIC_DISCOVERY_ACTIVE) {
+            return;
+        }
+
+        if (i == (numCharacteristics - 1)) {
+            discoveredCharacteristic = characteristics[i];
+            break;
+        } else {
+            characteristics[i].setLastHandle(characteristics[i + 1].getDeclHandle() - 1);
+        }
+
+        if ((matchingCharacteristicUUID == UUID::ShortUUIDBytes_t(BLE_UUID_UNKNOWN)) ||
+            ((matchingCharacteristicUUID == characteristics[i].getUUID()) &&
+             (matchingServiceUUID != UUID::ShortUUIDBytes_t(BLE_UUID_UNKNOWN)))) {
+            if (characteristicCallback) {
+                characteristicCallback(&characteristics[i]);
+            }
+        }
+    }
+
+    if (state != CHARACTERISTIC_DISCOVERY_ACTIVE) {
+        return;
+    }
+
+    Gap::Handle_t startHandle = (numCharacteristics > 0) ? characteristics[numCharacteristics - 1].getValueHandle() + 1 : SRV_DISC_END_HANDLE;
+    Gap::Handle_t endHandle   = services[serviceIndex].getEndHandle();
+    resetDiscoveredCharacteristics(); /* Note: resetDiscoveredCharacteristics() must come after fetching start and end Handles. */
+
+    if (startHandle < endHandle) {
+        ble_gattc_handle_range_t handleRange = {
+            .start_handle = startHandle,
+            .end_handle   = endHandle
+        };
+        if (sd_ble_gattc_characteristics_discover(connHandle, &handleRange) != NRF_SUCCESS) {
+            terminateCharacteristicDiscovery(BLE_ERROR_UNSPECIFIED);
+        }
+    } else {
+        terminateCharacteristicDiscovery(BLE_ERROR_NONE);
+    }
+}
+
+void
+nRF5xServiceDiscovery::progressServiceDiscovery(void)
+{
+    /* Iterate through the previously discovered services cached in services[]. */
+    while ((state == SERVICE_DISCOVERY_ACTIVE) && (serviceIndex < numServices)) {
+        if ((matchingServiceUUID == UUID::ShortUUIDBytes_t(BLE_UUID_UNKNOWN)) ||
+            (matchingServiceUUID == services[serviceIndex].getUUID())) {
+
+            if (serviceCallback && (matchingCharacteristicUUID == UUID::ShortUUIDBytes_t(BLE_UUID_UNKNOWN))) {
+                serviceCallback(&services[serviceIndex]);
+            }
+
+            if ((state == SERVICE_DISCOVERY_ACTIVE) && characteristicCallback) {
+                launchCharacteristicDiscovery(connHandle, services[serviceIndex].getStartHandle(), services[serviceIndex].getEndHandle());
+            } else {
+                serviceIndex++;
+            }
+        } else {
+            serviceIndex++;
+        }
+    }
+
+    /* Relaunch discovery of new services beyond the last entry cached in services[]. */
+    if ((state == SERVICE_DISCOVERY_ACTIVE) && (numServices > 0) && (serviceIndex > 0)) {
+        /* Determine the ending handle of the last cached service. */
+        Gap::Handle_t endHandle = services[serviceIndex - 1].getEndHandle();
+        resetDiscoveredServices(); /* Note: resetDiscoveredServices() must come after fetching endHandle. */
+
+        if (endHandle == SRV_DISC_END_HANDLE) {
+            terminateServiceDiscovery();
+        } else {
+            if (sd_ble_gattc_primary_services_discover(connHandle, endHandle, NULL) != NRF_SUCCESS) {
+                terminateServiceDiscovery();
+            }
+        }
+    }
+}
+
+void
+nRF5xServiceDiscovery::ServiceUUIDDiscoveryQueue::triggerFirst(void)
+{
+    while (numIndices) { /* loop until a call to char_value_by_uuid_read() succeeds or we run out of pending indices. */
+        parentDiscoveryObject->state = DISCOVER_SERVICE_UUIDS;
+
+        unsigned serviceIndex = getFirst();
+        ble_uuid_t uuid = {
+            .uuid = BLE_UUID_SERVICE_PRIMARY,
+            .type = BLE_UUID_TYPE_BLE,
+        };
+        ble_gattc_handle_range_t handleRange = {
+            .start_handle = parentDiscoveryObject->services[serviceIndex].getStartHandle(),
+            .end_handle   = parentDiscoveryObject->services[serviceIndex].getEndHandle(),
+        };
+        if (sd_ble_gattc_char_value_by_uuid_read(parentDiscoveryObject->connHandle, &uuid, &handleRange) == NRF_SUCCESS) {
+            return;
+        }
+
+        /* Skip this service if we fail to launch a read for its service-declaration
+         * attribute. Its UUID will remain INVALID, and it may not match any filters. */
+        dequeue();
+    }
+
+    /* Switch back to service discovery upon exhausting the service-indices pending UUID discovery. */
+    if (parentDiscoveryObject->state == DISCOVER_SERVICE_UUIDS) {
+        parentDiscoveryObject->state = SERVICE_DISCOVERY_ACTIVE;
+    }
+}
+
+void
+nRF5xServiceDiscovery::CharUUIDDiscoveryQueue::triggerFirst(void)
+{
+    while (numIndices) { /* loop until a call to char_value_by_uuid_read() succeeds or we run out of pending indices. */
+        parentDiscoveryObject->state = DISCOVER_CHARACTERISTIC_UUIDS;
+
+        unsigned charIndex = getFirst();
+        ble_uuid_t uuid = {
+            .uuid = BLE_UUID_CHARACTERISTIC,
+            .type = BLE_UUID_TYPE_BLE,
+        };
+        ble_gattc_handle_range_t handleRange = { };
+        handleRange.start_handle = parentDiscoveryObject->characteristics[charIndex].getDeclHandle();
+        handleRange.end_handle   = parentDiscoveryObject->characteristics[charIndex].getDeclHandle() + 1;
+        if (sd_ble_gattc_char_value_by_uuid_read(parentDiscoveryObject->connHandle, &uuid, &handleRange) == NRF_SUCCESS) {
+            return;
+        }
+
+        /* Skip this service if we fail to launch a read for its service-declaration
+         * attribute. Its UUID will remain INVALID, and it may not match any filters. */
+        dequeue();
+    }
+
+    /* Switch back to service discovery upon exhausting the service-indices pending UUID discovery. */
+    if (parentDiscoveryObject->state == DISCOVER_CHARACTERISTIC_UUIDS) {
+        parentDiscoveryObject->state = CHARACTERISTIC_DISCOVERY_ACTIVE;
+    }
+}
+
+void
+nRF5xServiceDiscovery::processDiscoverUUIDResponse(const ble_gattc_evt_char_val_by_uuid_read_rsp_t *response)
+{
+    if (state == DISCOVER_SERVICE_UUIDS) {
+        if ((response->count == 1) && (response->value_len == UUID::LENGTH_OF_LONG_UUID)) {
+            UUID::LongUUIDBytes_t uuid;
+            memcpy(uuid, response->handle_value[0].p_value, UUID::LENGTH_OF_LONG_UUID);
+
+            unsigned serviceIndex = serviceUUIDDiscoveryQueue.dequeue();
+            services[serviceIndex].setupLongUUID(uuid, UUID::LSB);
+
+            serviceUUIDDiscoveryQueue.triggerFirst();
+        } else {
+            serviceUUIDDiscoveryQueue.dequeue();
+        }
+    } else if (state == DISCOVER_CHARACTERISTIC_UUIDS) {
+        if ((response->count == 1) && (response->value_len == UUID::LENGTH_OF_LONG_UUID + 1 /* props */ + 2 /* value handle */)) {
+            UUID::LongUUIDBytes_t uuid;
+
+            memcpy(uuid, &(response->handle_value[0].p_value[3]), UUID::LENGTH_OF_LONG_UUID);
+
+            unsigned charIndex = charUUIDDiscoveryQueue.dequeue();
+            characteristics[charIndex].setupLongUUID(uuid, UUID::LSB);
+
+            charUUIDDiscoveryQueue.triggerFirst();
+        } else {
+            charUUIDDiscoveryQueue.dequeue();
+        }
+    }
+}
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