wifi: Add utility for struct conversions

Add a new utility file (hidl_struct_util) which would contain helper
functions to convert legacy HAL structures to HIDL structures and vice
versa.
Added utility functions to convert:
1. Background scan params from HIDL to legacy.
2. Scan Result from legacy to HIDL.
3. Cached Scan results from legacy to HIDL.
4. Link layer stats from legacy to HIDL.

Bug: 31991459
Test: Compiles
Change-Id: I48a49b43d425f8cc3059241c4bd652b2346f2381

3 files changed, 329 insertions, 0 deletions

diff --git a/wifi/1.0/default/Android.mk b/wifi/1.0/default/Android.mk
index 62d2e0bb04..931a3141b1 100644
--- a/wifi/1.0/default/Android.mk
+++ b/wifi/1.0/default/Android.mk
@@ -18,6 +18,7 @@ LOCAL_MODULE := android.hardware.wifi@1.0-service
 LOCAL_MODULE_RELATIVE_PATH := hw
 LOCAL_CPPFLAGS := -Wall -Wno-unused-parameter -Werror -Wextra
 LOCAL_SRC_FILES := \
+    hidl_struct_util.cpp \
     service.cpp \
     wifi.cpp \
     wifi_ap_iface.cpp \
diff --git a/wifi/1.0/default/hidl_struct_util.cpp b/wifi/1.0/default/hidl_struct_util.cpp
new file mode 100644
index 0000000000..b4dcc0a725
--- /dev/null
+++ b/wifi/1.0/default/hidl_struct_util.cpp
@@ -0,0 +1,259 @@
+/*
+ * Copyright (C) 2016 The Android Open Source Project
+ *
+ * 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 <android-base/logging.h>
+#include <utils/SystemClock.h>
+
+#include "hidl_struct_util.h"
+
+namespace android {
+namespace hardware {
+namespace wifi {
+namespace V1_0 {
+namespace implementation {
+namespace hidl_struct_util {
+
+uint8_t ConvertHidlReportEventFlagToLegacy(
+    StaBackgroundScanBucketEventReportSchemeMask hidl_flag) {
+  using HidlFlag = StaBackgroundScanBucketEventReportSchemeMask;
+  switch (hidl_flag) {
+    case HidlFlag::EACH_SCAN:
+      return REPORT_EVENTS_EACH_SCAN;
+    case HidlFlag::FULL_RESULTS:
+      return REPORT_EVENTS_FULL_RESULTS;
+    case HidlFlag::NO_BATCH:
+      return REPORT_EVENTS_NO_BATCH;
+  };
+}
+
+bool convertHidlScanParamsToLegacy(
+    const StaBackgroundScanParameters& hidl_scan_params,
+    legacy_hal::wifi_scan_cmd_params* legacy_scan_params) {
+  if (!legacy_scan_params) {
+    return false;
+  }
+  legacy_scan_params->base_period = hidl_scan_params.basePeriodInMs;
+  legacy_scan_params->max_ap_per_scan = hidl_scan_params.maxApPerScan;
+  legacy_scan_params->report_threshold_percent =
+      hidl_scan_params.reportThresholdPercent;
+  legacy_scan_params->report_threshold_num_scans =
+      hidl_scan_params.reportThresholdNumScans;
+  // TODO(b/33194311): Expose these max limits in the HIDL interface.
+  if (hidl_scan_params.buckets.size() > MAX_BUCKETS) {
+    return false;
+  }
+  legacy_scan_params->num_buckets = hidl_scan_params.buckets.size();
+  for (uint32_t bucket_idx = 0; bucket_idx < hidl_scan_params.buckets.size();
+       bucket_idx++) {
+    const StaBackgroundScanBucketParameters& hidl_bucket_spec =
+        hidl_scan_params.buckets[bucket_idx];
+    legacy_hal::wifi_scan_bucket_spec& legacy_bucket_spec =
+        legacy_scan_params->buckets[bucket_idx];
+    legacy_bucket_spec.bucket = bucket_idx;
+    legacy_bucket_spec.band =
+        static_cast<legacy_hal::wifi_band>(hidl_bucket_spec.band);
+    legacy_bucket_spec.period = hidl_bucket_spec.periodInMs;
+    legacy_bucket_spec.max_period = hidl_bucket_spec.exponentialMaxPeriodInMs;
+    legacy_bucket_spec.base = hidl_bucket_spec.exponentialBase;
+    legacy_bucket_spec.step_count = hidl_bucket_spec.exponentialStepCount;
+    legacy_bucket_spec.report_events = 0;
+    using HidlFlag = StaBackgroundScanBucketEventReportSchemeMask;
+    for (const auto flag :
+         {HidlFlag::EACH_SCAN, HidlFlag::FULL_RESULTS, HidlFlag::NO_BATCH}) {
+      if (hidl_bucket_spec.eventReportScheme &
+          static_cast<std::underlying_type<HidlFlag>::type>(flag)) {
+        legacy_bucket_spec.report_events |=
+            ConvertHidlReportEventFlagToLegacy(flag);
+      }
+    }
+    // TODO(b/33194311): Expose these max limits in the HIDL interface.
+    if (hidl_bucket_spec.frequencies.size() > MAX_CHANNELS) {
+      return false;
+    }
+    legacy_bucket_spec.num_channels = hidl_bucket_spec.frequencies.size();
+    for (uint32_t freq_idx = 0; freq_idx < hidl_bucket_spec.frequencies.size();
+         freq_idx++) {
+      legacy_bucket_spec.channels[freq_idx].channel =
+          hidl_bucket_spec.frequencies[freq_idx];
+    }
+  }
+  return true;
+}
+
+bool convertLegacyIeBlobToHidl(const uint8_t* ie_blob,
+                               uint32_t ie_blob_len,
+                               std::vector<WifiInformationElement>* hidl_ies) {
+  if (!ie_blob || !hidl_ies) {
+    return false;
+  }
+  const uint8_t* ies_begin = ie_blob;
+  const uint8_t* ies_end = ie_blob + ie_blob_len;
+  const uint8_t* next_ie = ies_begin;
+  using wifi_ie = legacy_hal::wifi_information_element;
+  constexpr size_t kIeHeaderLen = sizeof(wifi_ie);
+  // Each IE should atleast have the header (i.e |id| & |len| fields).
+  while (next_ie + kIeHeaderLen <= ies_end) {
+    const wifi_ie& legacy_ie = (*reinterpret_cast<const wifi_ie*>(next_ie));
+    uint32_t curr_ie_len = kIeHeaderLen + legacy_ie.len;
+    if (next_ie + curr_ie_len > ies_end) {
+      return false;
+    }
+    WifiInformationElement hidl_ie;
+    hidl_ie.id = legacy_ie.id;
+    hidl_ie.data =
+        std::vector<uint8_t>(legacy_ie.data, legacy_ie.data + legacy_ie.len);
+    hidl_ies->push_back(std::move(hidl_ie));
+    next_ie += curr_ie_len;
+  }
+  // Ensure that the blob has been fully consumed.
+  return (next_ie == ies_end);
+}
+
+bool convertLegacyScanResultToHidl(
+    const legacy_hal::wifi_scan_result& legacy_scan_result,
+    bool has_ie_data,
+    StaScanResult* hidl_scan_result) {
+  if (!hidl_scan_result) {
+    return false;
+  }
+  hidl_scan_result->timeStampInUs = legacy_scan_result.ts;
+  hidl_scan_result->ssid = std::vector<uint8_t>(
+      legacy_scan_result.ssid,
+      legacy_scan_result.ssid + sizeof(legacy_scan_result.ssid));
+  memcpy(hidl_scan_result->bssid.data(),
+         legacy_scan_result.bssid,
+         hidl_scan_result->bssid.size());
+  hidl_scan_result->frequency = legacy_scan_result.channel;
+  hidl_scan_result->rssi = legacy_scan_result.rssi;
+  hidl_scan_result->beaconPeriodInMs = legacy_scan_result.beacon_period;
+  hidl_scan_result->capability = legacy_scan_result.capability;
+  if (has_ie_data) {
+    std::vector<WifiInformationElement> ies;
+    if (!convertLegacyIeBlobToHidl(
+            reinterpret_cast<const uint8_t*>(legacy_scan_result.ie_data),
+            legacy_scan_result.ie_length,
+            &ies)) {
+      return false;
+    }
+    hidl_scan_result->informationElements = std::move(ies);
+  }
+  return true;
+}
+
+bool convertLegacyCachedScanResultsToHidl(
+    const legacy_hal::wifi_cached_scan_results& legacy_cached_scan_result,
+    StaScanData* hidl_scan_data) {
+  if (!hidl_scan_data) {
+    return false;
+  }
+  hidl_scan_data->flags = legacy_cached_scan_result.flags;
+  hidl_scan_data->bucketsScanned = legacy_cached_scan_result.buckets_scanned;
+
+  CHECK(legacy_cached_scan_result.num_results >= 0 &&
+        legacy_cached_scan_result.num_results <= MAX_AP_CACHE_PER_SCAN);
+  std::vector<StaScanResult> hidl_scan_results;
+  for (int32_t result_idx = 0;
+       result_idx < legacy_cached_scan_result.num_results;
+       result_idx++) {
+    StaScanResult hidl_scan_result;
+    if (!convertLegacyScanResultToHidl(
+            legacy_cached_scan_result.results[result_idx],
+            false,
+            &hidl_scan_result)) {
+      return false;
+    }
+    hidl_scan_results.push_back(hidl_scan_result);
+  }
+  hidl_scan_data->results = std::move(hidl_scan_results);
+  return true;
+}
+
+bool convertLegacyVectorOfCachedScanResultsToHidl(
+    const std::vector<legacy_hal::wifi_cached_scan_results>&
+        legacy_cached_scan_results,
+    std::vector<StaScanData>* hidl_scan_datas) {
+  if (!hidl_scan_datas) {
+    return false;
+  }
+  for (const auto& legacy_cached_scan_result : legacy_cached_scan_results) {
+    StaScanData hidl_scan_data;
+    if (!convertLegacyCachedScanResultsToHidl(legacy_cached_scan_result,
+                                              &hidl_scan_data)) {
+      return false;
+    }
+    hidl_scan_datas->push_back(hidl_scan_data);
+  }
+  return true;
+}
+
+bool convertLegacyLinkLayerStatsToHidl(
+    const legacy_hal::LinkLayerStats& legacy_stats,
+    StaLinkLayerStats* hidl_stats) {
+  if (!hidl_stats) {
+    return false;
+  }
+  // iface legacy_stats conversion.
+  hidl_stats->iface.beaconRx = legacy_stats.iface.beacon_rx;
+  hidl_stats->iface.avgRssiMgmt = legacy_stats.iface.rssi_mgmt;
+  hidl_stats->iface.wmeBePktStats.rxMpdu =
+      legacy_stats.iface.ac[legacy_hal::WIFI_AC_BE].rx_mpdu;
+  hidl_stats->iface.wmeBePktStats.txMpdu =
+      legacy_stats.iface.ac[legacy_hal::WIFI_AC_BE].tx_mpdu;
+  hidl_stats->iface.wmeBePktStats.lostMpdu =
+      legacy_stats.iface.ac[legacy_hal::WIFI_AC_BE].mpdu_lost;
+  hidl_stats->iface.wmeBePktStats.retries =
+      legacy_stats.iface.ac[legacy_hal::WIFI_AC_BE].retries;
+  hidl_stats->iface.wmeBkPktStats.rxMpdu =
+      legacy_stats.iface.ac[legacy_hal::WIFI_AC_BK].rx_mpdu;
+  hidl_stats->iface.wmeBkPktStats.txMpdu =
+      legacy_stats.iface.ac[legacy_hal::WIFI_AC_BK].tx_mpdu;
+  hidl_stats->iface.wmeBkPktStats.lostMpdu =
+      legacy_stats.iface.ac[legacy_hal::WIFI_AC_BK].mpdu_lost;
+  hidl_stats->iface.wmeBkPktStats.retries =
+      legacy_stats.iface.ac[legacy_hal::WIFI_AC_BK].retries;
+  hidl_stats->iface.wmeViPktStats.rxMpdu =
+      legacy_stats.iface.ac[legacy_hal::WIFI_AC_VI].rx_mpdu;
+  hidl_stats->iface.wmeViPktStats.txMpdu =
+      legacy_stats.iface.ac[legacy_hal::WIFI_AC_VI].tx_mpdu;
+  hidl_stats->iface.wmeViPktStats.lostMpdu =
+      legacy_stats.iface.ac[legacy_hal::WIFI_AC_VI].mpdu_lost;
+  hidl_stats->iface.wmeViPktStats.retries =
+      legacy_stats.iface.ac[legacy_hal::WIFI_AC_VI].retries;
+  hidl_stats->iface.wmeVoPktStats.rxMpdu =
+      legacy_stats.iface.ac[legacy_hal::WIFI_AC_VO].rx_mpdu;
+  hidl_stats->iface.wmeVoPktStats.txMpdu =
+      legacy_stats.iface.ac[legacy_hal::WIFI_AC_VO].tx_mpdu;
+  hidl_stats->iface.wmeVoPktStats.lostMpdu =
+      legacy_stats.iface.ac[legacy_hal::WIFI_AC_VO].mpdu_lost;
+  hidl_stats->iface.wmeVoPktStats.retries =
+      legacy_stats.iface.ac[legacy_hal::WIFI_AC_VO].retries;
+  // radio legacy_stats conversion.
+  hidl_stats->radio.onTimeInMs = legacy_stats.radio.on_time;
+  hidl_stats->radio.txTimeInMs = legacy_stats.radio.tx_time;
+  hidl_stats->radio.rxTimeInMs = legacy_stats.radio.rx_time;
+  hidl_stats->radio.onTimeInMsForScan = legacy_stats.radio.on_time_scan;
+  hidl_stats->radio.txTimeInMsPerLevel = legacy_stats.radio_tx_time_per_levels;
+  // Timestamp in the HAL wrapper here since it's not provided in the legacy
+  // HAL API.
+  hidl_stats->timeStampInMs = uptimeMillis();
+  return true;
+}
+}  // namespace hidl_struct_util
+}  // namespace implementation
+}  // namespace V1_0
+}  // namespace wifi
+}  // namespace hardware
+}  // namespace android
diff --git a/wifi/1.0/default/hidl_struct_util.h b/wifi/1.0/default/hidl_struct_util.h
new file mode 100644
index 0000000000..6c91e038bb
--- /dev/null
+++ b/wifi/1.0/default/hidl_struct_util.h
@@ -0,0 +1,69 @@
+/*
+ * Copyright (C) 2016 The Android Open Source Project
+ *
+ * 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.
+ */
+
+#ifndef HIDL_STRUCT_UTIL_H_
+#define HIDL_STRUCT_UTIL_H_
+
+#include <vector>
+
+#include <android/hardware/wifi/1.0/IWifi.h>
+
+#include "wifi_legacy_hal.h"
+
+/**
+ * This file contains a bunch of functions to convert structs from the legacy
+ * HAL to HIDL and vice versa.
+ * TODO(b/32093047): Add unit tests for these conversion methods in the VTS test
+ * suite.
+ */
+namespace android {
+namespace hardware {
+namespace wifi {
+namespace V1_0 {
+namespace implementation {
+namespace hidl_struct_util {
+
+// Convert hidl gscan params to legacy gscan params.
+bool convertHidlScanParamsToLegacy(
+    const StaBackgroundScanParameters& hidl_scan_params,
+    legacy_hal::wifi_scan_cmd_params* legacy_scan_params);
+// Convert the blob of packed IE elements to vector of
+// |WifiInformationElement| structures.
+bool convertLegacyIeBlobToHidl(const uint8_t* ie_blob,
+                               uint32_t ie_blob_len,
+                               std::vector<WifiInformationElement>* hidl_ies);
+// |has_ie_data| indicates whether or not the wifi_scan_result includes 802.11
+// Information Elements (IEs)
+bool convertLegacyScanResultToHidl(
+    const legacy_hal::wifi_scan_result& legacy_scan_result,
+    bool has_ie_data,
+    StaScanResult* hidl_scan_result);
+// |cached_results| is assumed to not include IEs.
+bool convertLegacyVectorOfCachedScanResultsToHidl(
+    const std::vector<legacy_hal::wifi_cached_scan_results>&
+        legacy_cached_scan_results,
+    std::vector<StaScanData>* hidl_scan_datas);
+bool convertLegacyLinkLayerStatsToHidl(
+    const legacy_hal::LinkLayerStats& legacy_stats,
+    StaLinkLayerStats* hidl_stats);
+}  // namespace hidl_struct_util
+}  // namespace implementation
+}  // namespace V1_0
+}  // namespace wifi
+}  // namespace hardware
+}  // namespace android
+
+#endif  // HIDL_STRUCT_UTIL_H_