simpleperf: set scoped arch and event types in RecordFileReader.

To record on device and report on host, simpleperf keeps arch type
and event types in perf.data. Currently, RecordFileReader needs
its users to read and set the arch type and event types properly.

This patch changes to let RecordFileReader set arch type and
event types. It avoids repeating the effort in users of
RecordFileReader.

Bug: none
Test: run simpleperf_unit_test.
Test: run simpleperf record on device, and report it on host.
Change-Id: Ief637ca6e2c3acfbf74b6447ef7ff0679439ca1d

1 files changed, 28 insertions, 14 deletions

diff --git a/simpleperf/record_file_reader.cpp b/simpleperf/record_file_reader.cpp
index 4e246b91..d57d3d8d 100644
--- a/simpleperf/record_file_reader.cpp
+++ b/simpleperf/record_file_reader.cpp
@@ -78,9 +78,10 @@ std::unique_ptr<RecordFileReader> RecordFileReader::CreateInstance(const std::st
   }
   auto reader = std::unique_ptr<RecordFileReader>(new RecordFileReader(filename, fp));
   if (!reader->ReadHeader() || !reader->ReadAttrSection() ||
-      !reader->ReadFeatureSectionDescriptors()) {
+      !reader->ReadFeatureSectionDescriptors() || !reader->ReadMetaInfoFeature()) {
     return nullptr;
   }
+  reader->UseRecordingEnvironment();
   return reader;
 }
 
@@ -205,6 +206,17 @@ bool RecordFileReader::ReadIdsForAttr(const FileAttr& attr, std::vector<uint64_t
   return true;
 }
 
+void RecordFileReader::UseRecordingEnvironment() {
+  std::string arch = ReadFeatureString(FEAT_ARCH);
+  if (!arch.empty()) {
+    scoped_arch_.reset(new ScopedCurrentArch(GetArchType(arch)));
+  }
+  auto& meta_info = GetMetaInfoFeature();
+  if (auto it = meta_info.find("event_type_info"); it != meta_info.end()) {
+    scoped_event_types_.reset(new ScopedEventTypes(it->second));
+  }
+}
+
 bool RecordFileReader::ReadDataSection(
     const std::function<bool(std::unique_ptr<Record>)>& callback) {
   std::unique_ptr<Record> record;
@@ -471,19 +483,21 @@ bool RecordFileReader::ReadFileFeature(size_t& read_pos,
   return true;
 }
 
-bool RecordFileReader::ReadMetaInfoFeature(std::unordered_map<std::string, std::string>* info_map) {
-  std::vector<char> buf;
-  if (!ReadFeatureSection(FEAT_META_INFO, &buf)) {
-    return false;
-  }
-  const char* p = buf.data();
-  const char* end = buf.data() + buf.size();
-  while (p < end) {
-    const char* key = p;
-    const char* value = key + strlen(key) + 1;
-    CHECK(value < end);
-    (*info_map)[p] = value;
-    p = value + strlen(value) + 1;
+bool RecordFileReader::ReadMetaInfoFeature() {
+  if (feature_section_descriptors_.count(FEAT_META_INFO)) {
+    std::vector<char> buf;
+    if (!ReadFeatureSection(FEAT_META_INFO, &buf)) {
+      return false;
+    }
+    const char* p = buf.data();
+    const char* end = buf.data() + buf.size();
+    while (p < end) {
+      const char* key = p;
+      const char* value = key + strlen(key) + 1;
+      CHECK(value < end);
+      meta_info_[p] = value;
+      p = value + strlen(value) + 1;
+    }
   }
   return true;
 }