Componentize HistoryDatabase

chrome/browser/history/history_database.cc

Index: chrome/browser/history/history_database.cc
diff --git a/chrome/browser/history/history_database.cc b/chrome/browser/history/history_database.cc
deleted file mode 100644
index 0eb7a90e2ac0f394a3d9d6fec865268c3c2e0197..0000000000000000000000000000000000000000
--- a/chrome/browser/history/history_database.cc
+++ /dev/null
@@ -1,466 +0,0 @@
-// Copyright (c) 2012 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/history/history_database.h"
-
-#include <algorithm>
-#include <set>
-#include <string>
-
-#include "base/command_line.h"
-#include "base/files/file_util.h"
-#include "base/metrics/histogram.h"
-#include "base/rand_util.h"
-#include "base/strings/string_util.h"
-#include "base/time/time.h"
-#include "components/history/content/browser/download_constants_utils.h"
-#include "content/public/browser/download_interrupt_reasons.h"
-#include "sql/transaction.h"
-
-#if defined(OS_MACOSX)
-#include "base/mac/mac_util.h"
-#endif
-
-namespace history {
-
-namespace {
-
-// Current version number. We write databases at the "current" version number,
-// but any previous version that can read the "compatible" one can make do with
-// our database without *too* many bad effects.
-const int kCurrentVersionNumber = 29;
-const int kCompatibleVersionNumber = 16;
-const char kEarlyExpirationThresholdKey[] = "early_expiration_threshold";
-
-}  // namespace
-
-HistoryDatabase::HistoryDatabase()
-    : DownloadDatabase(ToHistoryDownloadInterruptReason(
-                           content::DOWNLOAD_INTERRUPT_REASON_NONE),
-                       ToHistoryDownloadInterruptReason(
-                           content::DOWNLOAD_INTERRUPT_REASON_CRASH)) {
-}
-
-HistoryDatabase::~HistoryDatabase() {
-}
-
-sql::InitStatus HistoryDatabase::Init(const base::FilePath& history_name) {
-  db_.set_histogram_tag("History");
-
-  // Set the exceptional sqlite error handler.
-  db_.set_error_callback(error_callback_);
-
-  // Set the database page size to something a little larger to give us
-  // better performance (we're typically seek rather than bandwidth limited).
-  // This only has an effect before any tables have been created, otherwise
-  // this is a NOP. Must be a power of 2 and a max of 8192.
-  db_.set_page_size(4096);
-
-  // Set the cache size. The page size, plus a little extra, times this
-  // value, tells us how much memory the cache will use maximum.
-  // 1000 * 4kB = 4MB
-  // TODO(brettw) scale this value to the amount of available memory.
-  db_.set_cache_size(1000);
-
-  // Note that we don't set exclusive locking here. That's done by
-  // BeginExclusiveMode below which is called later (we have to be in shared
-  // mode to start out for the in-memory backend to read the data).
-
-  if (!db_.Open(history_name))
-    return sql::INIT_FAILURE;
-
-  // Wrap the rest of init in a tranaction. This will prevent the database from
-  // getting corrupted if we crash in the middle of initialization or migration.
-  sql::Transaction committer(&db_);
-  if (!committer.Begin())
-    return sql::INIT_FAILURE;
-
-#if defined(OS_MACOSX)
-  // Exclude the history file from backups.
-  base::mac::SetFileBackupExclusion(history_name);
-#endif
-
-  // Prime the cache.
-  db_.Preload();
-
-  // Create the tables and indices.
-  // NOTE: If you add something here, also add it to
-  //       RecreateAllButStarAndURLTables.
-  if (!meta_table_.Init(&db_, GetCurrentVersion(), kCompatibleVersionNumber))
-    return sql::INIT_FAILURE;
-  if (!CreateURLTable(false) || !InitVisitTable() ||
-      !InitKeywordSearchTermsTable() || !InitDownloadTable() ||
-      !InitSegmentTables())
-    return sql::INIT_FAILURE;
-  CreateMainURLIndex();
-  CreateKeywordSearchTermsIndices();
-
-  // TODO(benjhayden) Remove at some point.
-  meta_table_.DeleteKey("next_download_id");
-
-  // Version check.
-  sql::InitStatus version_status = EnsureCurrentVersion();
-  if (version_status != sql::INIT_OK)
-    return version_status;
-
-  return committer.Commit() ? sql::INIT_OK : sql::INIT_FAILURE;
-}
-
-void HistoryDatabase::ComputeDatabaseMetrics(
-    const base::FilePath& history_name) {
-    base::TimeTicks start_time = base::TimeTicks::Now();
-  int64 file_size = 0;
-  if (!base::GetFileSize(history_name, &file_size))
-    return;
-  int file_mb = static_cast<int>(file_size / (1024 * 1024));
-  UMA_HISTOGRAM_MEMORY_MB("History.DatabaseFileMB", file_mb);
-
-  sql::Statement url_count(db_.GetUniqueStatement("SELECT count(*) FROM urls"));
-  if (!url_count.Step())
-    return;
-  UMA_HISTOGRAM_COUNTS("History.URLTableCount", url_count.ColumnInt(0));
-
-  sql::Statement visit_count(db_.GetUniqueStatement(
-      "SELECT count(*) FROM visits"));
-  if (!visit_count.Step())
-    return;
-  UMA_HISTOGRAM_COUNTS("History.VisitTableCount", visit_count.ColumnInt(0));
-
-  base::Time one_week_ago = base::Time::Now() - base::TimeDelta::FromDays(7);
-  sql::Statement weekly_visit_sql(db_.GetUniqueStatement(
-      "SELECT count(*) FROM visits WHERE visit_time > ?"));
-  weekly_visit_sql.BindInt64(0, one_week_ago.ToInternalValue());
-  int weekly_visit_count = 0;
-  if (weekly_visit_sql.Step())
-    weekly_visit_count = weekly_visit_sql.ColumnInt(0);
-  UMA_HISTOGRAM_COUNTS("History.WeeklyVisitCount", weekly_visit_count);
-
-  base::Time one_month_ago = base::Time::Now() - base::TimeDelta::FromDays(30);
-  sql::Statement monthly_visit_sql(db_.GetUniqueStatement(
-      "SELECT count(*) FROM visits WHERE visit_time > ? AND visit_time <= ?"));
-  monthly_visit_sql.BindInt64(0, one_month_ago.ToInternalValue());
-  monthly_visit_sql.BindInt64(1, one_week_ago.ToInternalValue());
-  int older_visit_count = 0;
-  if (monthly_visit_sql.Step())
-    older_visit_count = monthly_visit_sql.ColumnInt(0);
-  UMA_HISTOGRAM_COUNTS("History.MonthlyVisitCount",
-                       older_visit_count + weekly_visit_count);
-
-  UMA_HISTOGRAM_TIMES("History.DatabaseBasicMetricsTime",
-                      base::TimeTicks::Now() - start_time);
-
-  // Compute the advanced metrics even less often, pending timing data showing
-  // that's not necessary.
-  if (base::RandInt(1, 3) == 3) {
-    start_time = base::TimeTicks::Now();
-
-    // Collect all URLs visited within the last month.
-    sql::Statement url_sql(db_.GetUniqueStatement(
-        "SELECT url, last_visit_time FROM urls WHERE last_visit_time > ?"));
-    url_sql.BindInt64(0, one_month_ago.ToInternalValue());
-
-    // Count URLs (which will always be unique) and unique hosts within the last
-    // week and last month.
-    int week_url_count = 0;
-    int month_url_count = 0;
-    std::set<std::string> week_hosts;
-    std::set<std::string> month_hosts;
-    while (url_sql.Step()) {
-      GURL url(url_sql.ColumnString(0));
-      base::Time visit_time =
-          base::Time::FromInternalValue(url_sql.ColumnInt64(1));
-      ++month_url_count;
-      month_hosts.insert(url.host());
-      if (visit_time > one_week_ago) {
-        ++week_url_count;
-        week_hosts.insert(url.host());
-      }
-    }
-    UMA_HISTOGRAM_COUNTS("History.WeeklyURLCount", week_url_count);
-    UMA_HISTOGRAM_COUNTS_10000("History.WeeklyHostCount", week_hosts.size());
-    UMA_HISTOGRAM_COUNTS("History.MonthlyURLCount", month_url_count);
-    UMA_HISTOGRAM_COUNTS_10000("History.MonthlyHostCount", month_hosts.size());
-    UMA_HISTOGRAM_TIMES("History.DatabaseAdvancedMetricsTime",
-                        base::TimeTicks::Now() - start_time);
-  }
-}
-
-void HistoryDatabase::BeginExclusiveMode() {
-  // We can't use set_exclusive_locking() since that only has an effect before
-  // the DB is opened.
-  ignore_result(db_.Execute("PRAGMA locking_mode=EXCLUSIVE"));
-}
-
-// static
-int HistoryDatabase::GetCurrentVersion() {
-  return kCurrentVersionNumber;
-}
-
-void HistoryDatabase::BeginTransaction() {
-  db_.BeginTransaction();
-}
-
-void HistoryDatabase::CommitTransaction() {
-  db_.CommitTransaction();
-}
-
-void HistoryDatabase::RollbackTransaction() {
-  db_.RollbackTransaction();
-}
-
-bool HistoryDatabase::RecreateAllTablesButURL() {
-  if (!DropVisitTable())
-    return false;
-  if (!InitVisitTable())
-    return false;
-
-  if (!DropKeywordSearchTermsTable())
-    return false;
-  if (!InitKeywordSearchTermsTable())
-    return false;
-
-  if (!DropSegmentTables())
-    return false;
-  if (!InitSegmentTables())
-    return false;
-
-  CreateKeywordSearchTermsIndices();
-  return true;
-}
-
-void HistoryDatabase::Vacuum() {
-  DCHECK_EQ(0, db_.transaction_nesting()) <<
-      "Can not have a transaction when vacuuming.";
-  ignore_result(db_.Execute("VACUUM"));
-}
-
-void HistoryDatabase::TrimMemory(bool aggressively) {
-  db_.TrimMemory(aggressively);
-}
-
-bool HistoryDatabase::Raze() {
-  return db_.Raze();
-}
-
-bool HistoryDatabase::SetSegmentID(VisitID visit_id, SegmentID segment_id) {
-  sql::Statement s(db_.GetCachedStatement(SQL_FROM_HERE,
-      "UPDATE visits SET segment_id = ? WHERE id = ?"));
-  s.BindInt64(0, segment_id);
-  s.BindInt64(1, visit_id);
-  DCHECK(db_.GetLastChangeCount() == 1);
-
-  return s.Run();
-}
-
-SegmentID HistoryDatabase::GetSegmentID(VisitID visit_id) {
-  sql::Statement s(db_.GetCachedStatement(SQL_FROM_HERE,
-      "SELECT segment_id FROM visits WHERE id = ?"));
-  s.BindInt64(0, visit_id);
-
-  if (s.Step()) {
-    if (s.ColumnType(0) == sql::COLUMN_TYPE_NULL)
-      return 0;
-    else
-      return s.ColumnInt64(0);
-  }
-  return 0;
-}
-
-base::Time HistoryDatabase::GetEarlyExpirationThreshold() {
-  if (!cached_early_expiration_threshold_.is_null())
-    return cached_early_expiration_threshold_;
-
-  int64 threshold;
-  if (!meta_table_.GetValue(kEarlyExpirationThresholdKey, &threshold)) {
-    // Set to a very early non-zero time, so it's before all history, but not
-    // zero to avoid re-retrieval.
-    threshold = 1L;
-  }
-
-  cached_early_expiration_threshold_ = base::Time::FromInternalValue(threshold);
-  return cached_early_expiration_threshold_;
-}
-
-void HistoryDatabase::UpdateEarlyExpirationThreshold(base::Time threshold) {
-  meta_table_.SetValue(kEarlyExpirationThresholdKey,
-                       threshold.ToInternalValue());
-  cached_early_expiration_threshold_ = threshold;
-}
-
-sql::Connection& HistoryDatabase::GetDB() {
-  return db_;
-}
-
-// Migration -------------------------------------------------------------------
-
-sql::InitStatus HistoryDatabase::EnsureCurrentVersion() {
-  // We can't read databases newer than we were designed for.
-  if (meta_table_.GetCompatibleVersionNumber() > kCurrentVersionNumber) {
-    LOG(WARNING) << "History database is too new.";
-    return sql::INIT_TOO_NEW;
-  }
-
-  int cur_version = meta_table_.GetVersionNumber();
-
-  // Put migration code here
-
-  if (cur_version == 15) {
-    if (!db_.Execute("DROP TABLE starred") || !DropStarredIDFromURLs()) {
-      LOG(WARNING) << "Unable to update history database to version 16.";
-      return sql::INIT_FAILURE;
-    }
-    ++cur_version;
-    meta_table_.SetVersionNumber(cur_version);
-    meta_table_.SetCompatibleVersionNumber(
-        std::min(cur_version, kCompatibleVersionNumber));
-  }
-
-  if (cur_version == 16) {
-#if !defined(OS_WIN)
-    // In this version we bring the time format on Mac & Linux in sync with the
-    // Windows version so that profiles can be moved between computers.
-    MigrateTimeEpoch();
-#endif
-    // On all platforms we bump the version number, so on Windows this
-    // migration is a NOP. We keep the compatible version at 16 since things
-    // will basically still work, just history will be in the future if an
-    // old version reads it.
-    ++cur_version;
-    meta_table_.SetVersionNumber(cur_version);
-  }
-
-  if (cur_version == 17) {
-    // Version 17 was for thumbnails to top sites migration. We ended up
-    // disabling it though, so 17->18 does nothing.
-    ++cur_version;
-    meta_table_.SetVersionNumber(cur_version);
-  }
-
-  if (cur_version == 18) {
-    // This is the version prior to adding url_source column. We need to
-    // migrate the database.
-    cur_version = 19;
-    meta_table_.SetVersionNumber(cur_version);
-  }
-
-  if (cur_version == 19) {
-    cur_version++;
-    meta_table_.SetVersionNumber(cur_version);
-    // This was the thumbnail migration.  Obsolete.
-  }
-
-  if (cur_version == 20) {
-    // This is the version prior to adding the visit_duration field in visits
-    // database. We need to migrate the database.
-    if (!MigrateVisitsWithoutDuration()) {
-      LOG(WARNING) << "Unable to update history database to version 21.";
-      return sql::INIT_FAILURE;
-    }
-    ++cur_version;
-    meta_table_.SetVersionNumber(cur_version);
-  }
-
-  if (cur_version == 21) {
-    // The android_urls table's data schemal was changed in version 21.
-#if defined(OS_ANDROID)
-    if (!MigrateToVersion22()) {
-      LOG(WARNING) << "Unable to migrate the android_urls table to version 22";
-    }
-#endif
-    ++cur_version;
-    meta_table_.SetVersionNumber(cur_version);
-  }
-
-  if (cur_version == 22) {
-    if (!MigrateDownloadsState()) {
-      LOG(WARNING) << "Unable to fix invalid downloads state values";
-      // Invalid state values may cause crashes.
-      return sql::INIT_FAILURE;
-    }
-    cur_version++;
-    meta_table_.SetVersionNumber(cur_version);
-  }
-
-  if (cur_version == 23) {
-    if (!MigrateDownloadsReasonPathsAndDangerType()) {
-      LOG(WARNING) << "Unable to upgrade download interrupt reason and paths";
-      // Invalid state values may cause crashes.
-      return sql::INIT_FAILURE;
-    }
-    cur_version++;
-    meta_table_.SetVersionNumber(cur_version);
-  }
-
-  if (cur_version == 24) {
-    if (!MigratePresentationIndex()) {
-      LOG(WARNING) << "Unable to migrate history to version 25";
-      return sql::INIT_FAILURE;
-    }
-    cur_version++;
-    meta_table_.SetVersionNumber(cur_version);
-  }
-
-  if (cur_version == 25) {
-    if (!MigrateReferrer()) {
-      LOG(WARNING) << "Unable to migrate history to version 26";
-      return sql::INIT_FAILURE;
-    }
-    cur_version++;
-    meta_table_.SetVersionNumber(cur_version);
-  }
-
-  if (cur_version == 26) {
-    if (!MigrateDownloadedByExtension()) {
-      LOG(WARNING) << "Unable to migrate history to version 27";
-      return sql::INIT_FAILURE;
-    }
-    cur_version++;
-    meta_table_.SetVersionNumber(cur_version);
-  }
-
-  if (cur_version == 27) {
-    if (!MigrateDownloadValidators()) {
-      LOG(WARNING) << "Unable to migrate history to version 28";
-      return sql::INIT_FAILURE;
-    }
-    cur_version++;
-    meta_table_.SetVersionNumber(cur_version);
-  }
-
-  if (cur_version == 28) {
-    if (!MigrateMimeType()) {
-      LOG(WARNING) << "Unable to migrate history to version 29";
-      return sql::INIT_FAILURE;
-    }
-    cur_version++;
-    meta_table_.SetVersionNumber(cur_version);
-  }
-
-  // When the version is too old, we just try to continue anyway, there should
-  // not be a released product that makes a database too old for us to handle.
-  LOG_IF(WARNING, cur_version < GetCurrentVersion()) <<
-         "History database version " << cur_version << " is too old to handle.";
-
-  return sql::INIT_OK;
-}
-
-#if !defined(OS_WIN)
-void HistoryDatabase::MigrateTimeEpoch() {
-  // Update all the times in the URLs and visits table in the main database.
-  ignore_result(db_.Execute(
-      "UPDATE urls "
-      "SET last_visit_time = last_visit_time + 11644473600000000 "
-      "WHERE id IN (SELECT id FROM urls WHERE last_visit_time > 0);"));
-  ignore_result(db_.Execute(
-      "UPDATE visits "
-      "SET visit_time = visit_time + 11644473600000000 "
-      "WHERE id IN (SELECT id FROM visits WHERE visit_time > 0);"));
-  ignore_result(db_.Execute(
-      "UPDATE segment_usage "
-      "SET time_slot = time_slot + 11644473600000000 "
-      "WHERE id IN (SELECT id FROM segment_usage WHERE time_slot > 0);"));
-}
-#endif
-
-}  // namespace history