Upstream oodles of Chrome for Android code into Chromium.

chrome/browser/android/history_report/usage_reports_buffer_backend.cc

Index: chrome/browser/android/history_report/usage_reports_buffer_backend.cc
diff --git a/chrome/browser/android/history_report/usage_reports_buffer_backend.cc b/chrome/browser/android/history_report/usage_reports_buffer_backend.cc
new file mode 100644
index 0000000000000000000000000000000000000000..61a9d31e6b8d3b36797a346844566c71ebfa1d9d
--- /dev/null
+++ b/chrome/browser/android/history_report/usage_reports_buffer_backend.cc
@@ -0,0 +1,142 @@
+// Copyright 2015 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#include "chrome/browser/android/history_report/usage_reports_buffer_backend.h"
+
+#include <inttypes.h>
+
+#include "base/files/file_util.h"
+#include "base/logging.h"
+#include "base/strings/string_number_conversions.h"
+#include "chrome/browser/android/history_report/usage_report_util.h"
+#include "chrome/browser/android/proto/delta_file.pb.h"
+#include "third_party/leveldatabase/src/include/leveldb/comparator.h"
+#include "third_party/leveldatabase/src/include/leveldb/db.h"
+#include "third_party/leveldatabase/src/include/leveldb/iterator.h"
+#include "third_party/leveldatabase/src/include/leveldb/options.h"
+#include "third_party/leveldatabase/src/include/leveldb/slice.h"
+#include "third_party/leveldatabase/src/include/leveldb/status.h"
+#include "third_party/leveldatabase/src/include/leveldb/write_batch.h"
+
+namespace {
+const base::FilePath::CharType kBufferFileName[] =
+    FILE_PATH_LITERAL("UsageReportsBuffer");
+}  // namespace
+
+namespace history_report {
+
+UsageReportsBufferBackend::UsageReportsBufferBackend(const base::FilePath& dir)
+    : db_file_name_(dir.Append(kBufferFileName)) {}
+
+UsageReportsBufferBackend::~UsageReportsBufferBackend() {}
+
+bool UsageReportsBufferBackend::Init() {
+  leveldb::Options options;
+  options.create_if_missing = true;
+  options.max_open_files = 0;  // Use minimum number of files.
+  std::string path = db_file_name_.value();
+  leveldb::DB* db = NULL;
+  leveldb::Status status = leveldb::DB::Open(options, path, &db);
+  if (status.IsCorruption()) {
+    LOG(WARNING) << "Deleting possibly-corrupt database";
+    base::DeleteFile(db_file_name_, true);
+    status = leveldb::DB::Open(options, path, &db);
+  }
+  if (status.ok()) {
+    CHECK(db);
+    db_.reset(db);
+    return true;
+  }
+  LOG(WARNING) << "Unable to open " << path << ": "
+               << status.ToString();
+  return false;
+}
+
+void UsageReportsBufferBackend::AddVisit(const std::string& id,
+    int64 timestamp_ms,
+    bool typed_visit) {
+  if (!db_.get()) {
+    LOG(WARNING) << "AddVisit db not initilized.";
+    return;
+  }
+  history_report::UsageReport report;
+  report.set_id(id);
+  report.set_timestamp_ms(timestamp_ms);
+  report.set_typed_visit(typed_visit);
+  leveldb::WriteOptions writeOptions;
+  leveldb::Status status = db_->Put(
+      writeOptions,
+      leveldb::Slice(usage_report_util::ReportToKey(report)),
+      leveldb::Slice(report.SerializeAsString()));
+  if (!status.ok())
+    LOG(WARNING) << "AddVisit failed " << status.ToString();
+}
+
+scoped_ptr<std::vector<UsageReport> >
+UsageReportsBufferBackend::GetUsageReportsBatch(int batch_size) {
+  scoped_ptr<std::vector<UsageReport> > reports(new std::vector<UsageReport>());
+  if (!db_.get()) {
+    return reports.Pass();
+  }
+  reports->reserve(batch_size);
+  leveldb::ReadOptions options;
+  scoped_ptr<leveldb::Iterator> db_iter(db_->NewIterator(options));
+  db_iter->SeekToFirst();
+  while (batch_size > 0 && db_iter->Valid()) {
+    history_report::UsageReport last_report;
+    leveldb::Slice value_slice = db_iter->value();
+    if (last_report.ParseFromArray(value_slice.data(), value_slice.size())) {
+      reports->push_back(last_report);
+      --batch_size;
+    }
+    db_iter->Next();
+  }
+  return reports.Pass();
+}
+
+void UsageReportsBufferBackend::Remove(
+    const std::vector<std::string>& reports) {
+  if (!db_.get()) {
+    return;
+  }
+  // TODO(haaawk): investigate if it's worth sorting the keys here to improve
+  // performance.
+  leveldb::WriteBatch updates;
+  for (std::vector<std::string>::const_iterator it = reports.begin();
+       it != reports.end();
+       ++it) {
+    updates.Delete(leveldb::Slice(*it));
+  }
+
+  leveldb::WriteOptions write_options;
+  leveldb::Status status = db_->Write(write_options, &updates);
+  if (!status.ok()) {
+    LOG(WARNING) << "Remove failed: " << status.ToString();
+  }
+}
+
+void UsageReportsBufferBackend::Clear() {
+  db_.reset();
+  base::DeleteFile(db_file_name_, true);
+  Init();
+}
+
+std::string UsageReportsBufferBackend::Dump() {
+  std::string dump("\n UsageReportsBuffer [");
+  if (!db_.get()) {
+    dump.append("not initialized]");
+    return dump;
+  }
+  dump.append("num pending entries=");
+  leveldb::ReadOptions options;
+  int num_entries = 0;
+  scoped_ptr<leveldb::Iterator> db_it(db_->NewIterator(options));
+  for (db_it->SeekToFirst(); db_it->Valid(); db_it->Next()) num_entries++;
+  dump.append(base::IntToString(num_entries));
+  dump.append("]");
+  return dump;
+}
+
+}  // namespace history_report
+