Retrieve Windows performance assessment information from results files.

content/gpu/gpu_info_collector_win.cc

Index: content/gpu/gpu_info_collector_win.cc
diff --git a/content/gpu/gpu_info_collector_win.cc b/content/gpu/gpu_info_collector_win.cc
index 1533a48291856969387b87418626ecf0a102b624..c4e662ca20fff4e4cb1fda2af08800a650ac1295 100644
--- a/content/gpu/gpu_info_collector_win.cc
+++ b/content/gpu/gpu_info_collector_win.cc
@@ -11,6 +11,8 @@
 
 #include "base/command_line.h"
 #include "base/file_path.h"
+#include "base/file_util.h"
+#include "base/libxml_utils.h"
 #include "base/logging.h"
 #include "base/scoped_native_library.h"
 #include "base/string_number_conversions.h"
@@ -47,6 +49,25 @@ float GetAssessmentScore(IProvideWinSATResultsInfo* results,
   return score;
 }
 
+float GetAssessmentScoreFromFile(XmlReader* reader,
+                                        std::string assessment) {

[vangelis, 2012/04/24 00:37:30]

Watch indentation.

[dtu, 2012/05/01 00:32:16]

Done.

+  do {
+    if (reader->NodeName() == assessment) {
+      std::string score_string;
+      if (!reader->ReadElementContent(&score_string))
+        return 0.0;
+
+      double score;
+      if (!base::StringToDouble(score_string, &score))
+        return 0.0;
+
+      return static_cast<float>(score);
+    }
+  } while (reader->Read());
+
+  return 0.0;
+}
+
 content::GpuPerformanceStats RetrieveGpuPerformanceStats() {
   content::GpuPerformanceStats stats;
 
@@ -80,7 +101,42 @@ content::GpuPerformanceStats RetrieveGpuPerformanceStats() {
 
   if (state != WINSAT_ASSESSMENT_STATE_VALID &&
       state != WINSAT_ASSESSMENT_STATE_INCOHERENT_WITH_HARDWARE) {
-    LOG(ERROR) << "Can't retrieve a valid assessment";
+    // If the user re-runs the assessment without restarting, the COM API
+    // returns WINSAT_ASSESSMENT_STATE_NOT_AVAILABLE. For that case,
+    // fall back to reading the assessment result files directly.
+    file_util::FileEnumerator file_enumerator(

[vangelis, 2012/04/24 00:37:30]

Given the flakiness of the winsat api, we should always use the xml file for
retrieving the data.

[dtu, 2012/05/01 00:32:16]

Done.

+        FilePath(FILE_PATH_LITERAL("c:/Windows/Performance/WinSAT/DataStore/")),

[vangelis, 2012/04/24 00:37:30]

You should probably use %windir% instead of hardcoding c:/windows .

[dtu, 2012/05/01 00:32:16]

Done.

+        false,  // not recursive
+        file_util::FileEnumerator::FILES,
+        FILE_PATH_LITERAL("* * Formal.Assessment (*).WinSAT.xml"));
+
+    FilePath current_results;
+    for (FilePath results = file_enumerator.Next(); !results.empty();
+         results = file_enumerator.Next())
+      if (FilePath::CompareLessIgnoreCase(current_results.value(),
+                                          results.value()))
+        current_results = results;
+
+    if (current_results.empty()) {
+      LOG(ERROR) << "Can't retrieve a valid assessment";
+      return stats;
+    }
+
+    XmlReader reader;
+    reader.LoadFile(current_results);
+
+    stats.overall = GetAssessmentScoreFromFile(&reader, "SystemScore");

[vangelis, 2012/04/24 00:37:30]

The WinSAT xml schema is here:
http://msdn.microsoft.com/en-us/library/windows/desktop/aa969210(v=vs.85).aspx

It would be preferable to look for the <WinSPR> section first instead of doing
global searches for the stats.  

[dtu, 2012/05/01 00:32:16]

Done.

+    if (stats.overall == 0.0)
+      LOG(ERROR) << "Could not read overall score from assessment results.";
+
+    stats.graphics = GetAssessmentScoreFromFile(&reader, "GraphicsScore");
+    if (stats.graphics == 0.0)
+      LOG(ERROR) << "Could not read graphics score from assessment results.";
+
+    stats.gaming = GetAssessmentScoreFromFile(&reader, "GamingScore");
+    if (stats.gaming == 0.0)
+      LOG(ERROR) << "Could not read gaming score from assessment results.";
+
     return stats;
   }