Instrument safe-browsing to track file-format conversion.

Also track corruption separately for old and new file formats.

BUG=58552
TEST=none

Review URL: http://codereview.chromium.org/3632004

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@62198 0039d316-1c4b-4281-b951-d872f2087c98

2 files changed, 64 insertions, 4 deletions

diff --git a/chrome/browser/safe_browsing/safe_browsing_store_file.cc b/chrome/browser/safe_browsing/safe_browsing_store_file.cc
index 7402d9a..a30bf51 100644
--- a/chrome/browser/safe_browsing/safe_browsing_store_file.cc
+++ b/chrome/browser/safe_browsing/safe_browsing_store_file.cc
@@ -171,6 +171,11 @@ bool FileHeaderSanityCheck(const FilePath& filename,
 
 }  // namespace
 
+// static
+void SafeBrowsingStoreFile::RecordFormatEvent(FormatEventType event_type) {
+  UMA_HISTOGRAM_ENUMERATION("SB2.FormatEvent", event_type, FORMAT_EVENT_MAX);
+}
+
 SafeBrowsingStoreFile::SafeBrowsingStoreFile()
     : chunks_written_(0),
       file_(NULL),
@@ -251,6 +256,10 @@ bool SafeBrowsingStoreFile::WriteSubHash(int32 chunk_id, int32 add_chunk_id,
 }
 
 bool SafeBrowsingStoreFile::OnCorruptDatabase() {
+  if (!corruption_seen_)
+    RecordFormatEvent(FORMAT_EVENT_FILE_CORRUPT);
+  corruption_seen_ = true;
+
   if (corruption_callback_.get())
     corruption_callback_->Run();
 
@@ -258,6 +267,15 @@ bool SafeBrowsingStoreFile::OnCorruptDatabase() {
   return false;
 }
 
+void SafeBrowsingStoreFile::HandleCorruptDatabase() {
+  if (!corruption_seen_)
+    RecordFormatEvent(FORMAT_EVENT_SQLITE_CORRUPT);
+  corruption_seen_ = true;
+
+  if (corruption_callback_.get())
+    corruption_callback_->Run();
+}
+
 bool SafeBrowsingStoreFile::Close() {
   ClearUpdateBuffers();
 
@@ -282,6 +300,8 @@ bool SafeBrowsingStoreFile::BeginUpdate() {
   DCHECK(sub_hashes_.empty());
   DCHECK_EQ(chunks_written_, 0);
 
+  corruption_seen_ = false;
+
   const FilePath new_filename = TemporaryFileForFilename(filename_);
   file_util::ScopedFILE new_file(file_util::OpenFile(new_filename, "wb+"));
   if (new_file.get() == NULL)
@@ -304,6 +324,12 @@ bool SafeBrowsingStoreFile::BeginUpdate() {
       return OnCorruptDatabase();
 
   if (header.magic != kFileMagic || header.version != kFileVersion) {
+    if (!strcmp(reinterpret_cast<char*>(&header.magic), "SQLite format 3")) {
+      RecordFormatEvent(FORMAT_EVENT_FOUND_SQLITE);
+    } else {
+      RecordFormatEvent(FORMAT_EVENT_FOUND_UNKNOWN);
+    }
+
     // Something about having the file open causes a problem with
     // SQLite opening it.  Perhaps PRAGMA locking_mode = EXCLUSIVE?
     file.reset();
@@ -571,8 +597,11 @@ bool SafeBrowsingStoreFile::DoUpdate(
   if (old_store_.get()) {
     const bool deleted = old_store_->Delete();
     old_store_.reset();
-    if (!deleted)
+    if (!deleted) {
+      RecordFormatEvent(FORMAT_EVENT_SQLITE_DELETE_FAILED);
       return false;
+    }
+    RecordFormatEvent(FORMAT_EVENT_SQLITE_DELETED);
   } else {
     if (!file_util::Delete(filename_, false) &&
         file_util::PathExists(filename_))
diff --git a/chrome/browser/safe_browsing/safe_browsing_store_file.h b/chrome/browser/safe_browsing/safe_browsing_store_file.h
index 3530e60..ec612e6 100644
--- a/chrome/browser/safe_browsing/safe_browsing_store_file.h
+++ b/chrome/browser/safe_browsing/safe_browsing_store_file.h
@@ -160,6 +160,34 @@ class SafeBrowsingStoreFile : public SafeBrowsingStore {
   }
 
  private:
+  // Enumerate different format-change events for histogramming
+  // purposes.  DO NOT CHANGE THE ORDERING OF THESE VALUES.
+  // TODO(shess): Remove this once the format change is complete.
+  enum FormatEventType {
+    // Corruption detected, broken down by file format.
+    FORMAT_EVENT_FILE_CORRUPT,
+    FORMAT_EVENT_SQLITE_CORRUPT,
+
+    // The type of format found in the file.  The expected case (new
+    // file format) is intentionally not covered.
+    FORMAT_EVENT_FOUND_SQLITE,
+    FORMAT_EVENT_FOUND_UNKNOWN,
+
+    // The number of SQLite-format files deleted should be the same as
+    // FORMAT_EVENT_FOUND_SQLITE.  It can differ if the delete fails,
+    // or if a failure prevents the update from succeeding.
+    FORMAT_EVENT_SQLITE_DELETED,
+    FORMAT_EVENT_SQLITE_DELETE_FAILED,
+
+    // Histogram space is determined by the max.  If this is exceeded,
+    // simply start a new histogram.
+    FORMAT_EVENT_MAX = 50
+  };
+
+  // Helper to record an event related to format conversion from
+  // SQLite to file.
+  static void RecordFormatEvent(FormatEventType event_type);
+
   // Close all files and clear all buffers.
   bool Close();
 
@@ -169,9 +197,7 @@ class SafeBrowsingStoreFile : public SafeBrowsingStore {
 
   // Helper for creating a corruption callback for |old_store_|.
   // TODO(shess): Remove after migration.
-  void HandleCorruptDatabase() {
-    OnCorruptDatabase();
-  }
+  void HandleCorruptDatabase();
 
   // Clear temporary buffers used to accumulate chunk data.
   bool ClearChunkBuffers() {
@@ -235,6 +261,11 @@ class SafeBrowsingStoreFile : public SafeBrowsingStore {
 
   scoped_ptr<Callback0::Type> corruption_callback_;
 
+  // Tracks whether corruption has already been seen in the current
+  // update, so that only one instance is recorded in the stats.
+  // TODO(shess): Remove with format-migration support.
+  bool corruption_seen_;
+
   DISALLOW_COPY_AND_ASSIGN(SafeBrowsingStoreFile);
 };