commit fa2f91c2fe442df6cf4b030752a5332fe218f7e6
author Jeff Hamilton <jham@google.com> Fri Mar 22 00:25:02 2019 -0400
committer Jeff Hamilton <jham@google.com> Wed Mar 27 14:24:49 2019 -0400
tree f1c36ac1cf21f8041ff71c7ac4e42d35a6a0a88e
parent 112795a64613fd5a2b642d40160e64e59e4d870d

Add an API to read experiment IDs.

Change the file format to store the
experiment IDs direclty so we don't
need to parse the proto when reading
the values out.

Bug: 129099771
Test: bit statsd_test:* && adb shell cmd stats pull-source 10051
Change-Id: I0dc1fd118f4d9ba597c2f0959648136bbafb5aab

cmds/statsd/src/StatsService.cpp

diff --git a/cmds/statsd/src/StatsService.cpp b/cmds/statsd/src/StatsService.cpp
index 52ecdc8..0aacdf2 100644
--- a/cmds/statsd/src/StatsService.cpp
+++ b/cmds/statsd/src/StatsService.cpp
@@ -65,8 +65,6 @@
 
 // for StatsDataDumpProto
 const int FIELD_ID_REPORTS_LIST = 1;
-// for TrainInfo experiment id serialization
-const int FIELD_ID_EXPERIMENT_ID = 1;
 
 static binder::Status ok() {
     return binder::Status::ok();
@@ -1181,7 +1179,7 @@
 Status StatsService::sendBinaryPushStateChangedAtom(const android::String16& trainName,
                                                     int64_t trainVersionCode, int options,
                                                     int32_t state,
-                                                    const std::vector<int64_t>& experimentIds) {
+                                                    const std::vector<int64_t>& experimentIdsIn) {
     uid_t uid = IPCThreadState::self()->getCallingUid();
     // For testing
     if (uid == AID_ROOT || uid == AID_SYSTEM || uid == AID_SHELL) {
@@ -1201,7 +1199,7 @@
 
     bool readTrainInfoSuccess = false;
     InstallTrainInfo trainInfo;
-    if (trainVersionCode == -1 || experimentIds.empty() || trainName.size() == 0) {
+    if (trainVersionCode == -1 || experimentIdsIn.empty() || trainName.size() == 0) {
         readTrainInfoSuccess = StorageManager::readTrainInfo(trainInfo);
     }
 
@@ -1209,27 +1207,19 @@
         trainVersionCode = trainInfo.trainVersionCode;
     }
 
-    vector<uint8_t> experimentIdsProtoBuffer;
-    if (readTrainInfoSuccess && experimentIds.empty()) {
-        experimentIdsProtoBuffer = trainInfo.experimentIds;
+    // Find the right experiment IDs
+    std::vector<int64_t> experimentIds;
+    if (readTrainInfoSuccess && experimentIdsIn.empty()) {
+        experimentIds = trainInfo.experimentIds;
     } else {
-        ProtoOutputStream proto;
-        for (const auto& expId : experimentIds) {
-            proto.write(FIELD_TYPE_INT64 | FIELD_COUNT_REPEATED | FIELD_ID_EXPERIMENT_ID,
-                        (long long)expId);
-        }
-
-        experimentIdsProtoBuffer.resize(proto.size());
-        size_t pos = 0;
-        sp<ProtoReader> reader = proto.data();
-        while (reader->readBuffer() != NULL) {
-            size_t toRead = reader->currentToRead();
-            std::memcpy(&(experimentIdsProtoBuffer[pos]), reader->readBuffer(), toRead);
-            pos += toRead;
-            reader->move(toRead);
-        }
+        experimentIds = experimentIdsIn;
     }
 
+    // Flatten the experiment IDs to proto
+    vector<uint8_t> experimentIdsProtoBuffer;
+    writeExperimentIdsToProto(experimentIds, &experimentIdsProtoBuffer);
+
+    // Find the right train name
     std::string trainNameUtf8;
     if (readTrainInfoSuccess && trainName.size() == 0) {
         trainNameUtf8 = trainInfo.trainName;
@@ -1244,7 +1234,34 @@
     LogEvent event(trainNameUtf8, trainVersionCode, requiresStaging, rollbackEnabled,
                    requiresLowLatencyMonitor, state, experimentIdsProtoBuffer, userId);
     mProcessor->OnLogEvent(&event);
-    StorageManager::writeTrainInfo(trainVersionCode, trainNameUtf8, state, experimentIdsProtoBuffer);
+    StorageManager::writeTrainInfo(trainVersionCode, trainNameUtf8, state, experimentIds);
+    return Status::ok();
+}
+
+Status StatsService::getRegisteredExperimentIds(std::vector<int64_t>* experimentIdsOut) {
+    uid_t uid = IPCThreadState::self()->getCallingUid();
+
+    // Caller must be granted these permissions
+    if (!checkCallingPermission(String16(kPermissionDump))) {
+        return exception(binder::Status::EX_SECURITY,
+                         StringPrintf("UID %d lacks permission %s", uid, kPermissionDump));
+    }
+    if (!checkCallingPermission(String16(kPermissionUsage))) {
+        return exception(binder::Status::EX_SECURITY,
+                         StringPrintf("UID %d lacks permission %s", uid, kPermissionUsage));
+    }
+    // TODO: add verifier permission
+
+    // Read the latest train info
+    InstallTrainInfo trainInfo;
+    if (!StorageManager::readTrainInfo(trainInfo)) {
+        // No train info means no experiment IDs, return an empty list
+        experimentIdsOut->clear();
+        return Status::ok();
+    }
+
+    // Copy the experiment IDs to the out vector
+    experimentIdsOut->assign(trainInfo.experimentIds.begin(), trainInfo.experimentIds.end());
     return Status::ok();
 }