From 0be161e3bb4ca5d42c63a197cb3808c2d11ffcfc Mon Sep 17 00:00:00 2001
From: aaronyujiaze <aaronyujiaze@google.com>
Date: Fri, 20 May 2022 13:45:20 -0700
Subject: [PATCH] Add Copresence Service UUID to BLE Advertisement 0x16 Service
 Data

The medium abstraction layer does not prepopulate the advertisement_bytes ByteArray with Copresence Service UUID. This adds it at the platform impl layer.

PiperOrigin-RevId: 450054877
---
 .../implementation/windows/ble_medium.cc      |  6 ++++
 .../implementation/windows/ble_medium_test.cc | 33 +++++++------------
 2 files changed, 18 insertions(+), 21 deletions(-)

diff --git a/internal/platform/implementation/windows/ble_medium.cc b/internal/platform/implementation/windows/ble_medium.cc
index 536f85bd..477f428c 100644
--- a/internal/platform/implementation/windows/ble_medium.cc
+++ b/internal/platform/implementation/windows/ble_medium.cc
@@ -55,6 +55,9 @@ using ::winrt::Windows::Storage::Streams::DataWriter;
 
 template <typename T>
 using IVector = winrt::Windows::Foundation::Collections::IVector<T>;
+
+// Copresence Service UUID 0xfef3 (little-endian)
+constexpr uint16_t kCopresenceServiceUuid = 0xf3fe;
 }  // namespace
 
 BleMedium::BleMedium(api::BluetoothAdapter& adapter)
@@ -73,6 +76,9 @@ bool BleMedium::StartAdvertising(
 
   DataWriter data_writer;
 
+  // Copresence Service UUID 0xfef3 (little-endian)
+  data_writer.WriteUInt16(kCopresenceServiceUuid);
+
   for (int i = 0; i < advertisement_bytes.size(); ++i) {
     data_writer.WriteByte(
         static_cast<uint8_t>(*(advertisement_bytes.data() + i)));
diff --git a/internal/platform/implementation/windows/ble_medium_test.cc b/internal/platform/implementation/windows/ble_medium_test.cc
index 79e04d7b..4f84a1e4 100644
--- a/internal/platform/implementation/windows/ble_medium_test.cc
+++ b/internal/platform/implementation/windows/ble_medium_test.cc
@@ -30,7 +30,6 @@ namespace nearby {
 namespace windows {
 namespace {
 
-constexpr uint8_t kCopresenceServiceUuid[] = {0xfe, 0xf3};
 constexpr uint8_t kVersionBitmask = 0xE0;
 constexpr uint8_t kSocketVersionBitmask = 0x1C;
 constexpr uint8_t kFastAdvertisementFlagBitmask = 0x02;
@@ -41,13 +40,7 @@ TEST(BleMedium, DISABLED_StartAdvertising) {
   BluetoothAdapter bluetoothAdapter;
   BleMedium ble_medium(bluetoothAdapter);
 
-  std::array<char, 29> advertising_data_byte_array;
-
-  // (2 bytes) 16-bit Service UUID 0xf3fe
-  advertising_data_byte_array.at(0) =
-      static_cast<unsigned char>(kCopresenceServiceUuid[1]);
-  advertising_data_byte_array.at(1) =
-      static_cast<unsigned char>(kCopresenceServiceUuid[0]);
+  std::array<char, 27> advertising_data_byte_array;
 
   // (1 byte) version [3-bits] + socket_version [3-bits] +
   // fast_advertisement_flag [1-bit] + reserved [1-bit]
@@ -63,11 +56,11 @@ TEST(BleMedium, DISABLED_StartAdvertising) {
   ble_medium_advertisement_metadata_byte |=
       ((fast_advertisement ? 1 : 0) << 1) & kFastAdvertisementFlagBitmask;
 
-  advertising_data_byte_array.at(2) =
+  advertising_data_byte_array.at(0) =
       static_cast<unsigned char>(ble_medium_advertisement_metadata_byte);
 
   // (1 byte) body_length
-  advertising_data_byte_array.at(3) = static_cast<unsigned char>(
+  advertising_data_byte_array.at(1) = static_cast<unsigned char>(
       0x19);  // always 25 bytes for Fast Advertisement
 
   // (1 byte) Nearby Connection version [3-bits] + pcp [5-bits]
@@ -78,16 +71,16 @@ TEST(BleMedium, DISABLED_StartAdvertising) {
   uint8_t ble_connections_advertisement_metadata_byte =
       (ble_connections_version << 5) & kVersionBitmask;
   ble_connections_advertisement_metadata_byte |= pcp & kPcpBitmask;
-  advertising_data_byte_array.at(4) =
+  advertising_data_byte_array.at(2) =
       static_cast<unsigned char>(ble_connections_advertisement_metadata_byte);
 
   // (4 bytes) endpoint_id
   for (int i = 0; i < 4; ++i) {
-    advertising_data_byte_array.at(5 + i) = static_cast<unsigned char>(0x00);
+    advertising_data_byte_array.at(3 + i) = static_cast<unsigned char>(0x00);
   }
 
   // (1 byte) endpoint_info_size
-  advertising_data_byte_array.at(9) = static_cast<unsigned char>(
+  advertising_data_byte_array.at(7) = static_cast<unsigned char>(
       0x11);  // always 17-bytes for Fast Advertisement
 
   // =========endpoint_info [17-bytes]============
@@ -100,22 +93,22 @@ TEST(BleMedium, DISABLED_StartAdvertising) {
       (nearby_share_version << 5) & kVersionBitmask;
   nearby_share_metadata_byte |= ((visibility & kVisibilityBitmask) << 4);
 
-  advertising_data_byte_array.at(10) = static_cast<unsigned char>(0x00);
+  advertising_data_byte_array.at(8) = static_cast<unsigned char>(0x00);
 
   // (2 bytes) salt
   for (int i = 0; i < 2; ++i) {
-    advertising_data_byte_array.at(11 + i) = static_cast<unsigned char>(0x00);
+    advertising_data_byte_array.at(9 + i) = static_cast<unsigned char>(0x00);
   }
 
   // (14 bytes) encrypted_metadata_key
   for (int i = 0; i < 14; ++i) {
-    advertising_data_byte_array.at(13 + i) = static_cast<unsigned char>(0x00);
+    advertising_data_byte_array.at(11 + i) = static_cast<unsigned char>(0x00);
   }
   // =========endpoint_info [17-bytes]============
 
   // (2 bytes) device_token
   for (int i = 0; i < 2; ++i) {
-    advertising_data_byte_array.at(27 + i) = static_cast<unsigned char>(0x00);
+    advertising_data_byte_array.at(25 + i) = static_cast<unsigned char>(0x00);
   }
 
   ByteArray advertising_data(advertising_data_byte_array);
@@ -131,10 +124,8 @@ TEST(BleMedium, DISABLED_StopAdvertising) {
   std::array<char, 2> advertising_data_byte_array;
 
   // (2 bytes) 16-bit Service UUID 0xf3fe
-  advertising_data_byte_array.at(0) =
-      static_cast<unsigned char>(kCopresenceServiceUuid[1]);
-  advertising_data_byte_array.at(1) =
-      static_cast<unsigned char>(kCopresenceServiceUuid[0]);
+  advertising_data_byte_array.at(0) = static_cast<unsigned char>(0xf3);
+  advertising_data_byte_array.at(1) = static_cast<unsigned char>(0xfe);
 
   ByteArray advertising_data(advertising_data_byte_array);