Upstream oodles of Chrome for Android code into Chromium.

chrome/browser/android/history_report/delta_file_commons.cc

+// 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/delta_file_commons.h"
+
+#include <iomanip>
+
+#include "base/strings/string_number_conversions.h"
+#include "base/strings/utf_string_conversions.h"
+#include "crypto/sha2.h"
+#include "net/base/registry_controlled_domains/registry_controlled_domain.h"
+
+using bookmarks::BookmarkModel;
+using net::registry_controlled_domains::EXCLUDE_UNKNOWN_REGISTRIES;
+using net::registry_controlled_domains::EXCLUDE_PRIVATE_REGISTRIES;
+using net::registry_controlled_domains::GetRegistryLength;
+
+namespace {
+
+const int kBookmarkScoreBonusMultiplier = 3;
+const size_t kIdLengthLimit = 256;
+const int kSHA256ByteSize = 32;
+const size_t kUrlLengthLimit = 20 * 1024 * 1024; // 20M
+const size_t kUrlLengthWidth = 8;
+
+void StripTopLevelDomain(std::string* host) {
+  size_t registry_length = GetRegistryLength(
+      *host, EXCLUDE_UNKNOWN_REGISTRIES, EXCLUDE_PRIVATE_REGISTRIES);
+  if (registry_length != 0 && registry_length != std::string::npos)
+    host->erase(host->length() - (registry_length + 1));
+}
+
+void StripCommonSubDomains(std::string* host) {
+  std::string www_prefix("www.");
+  std::string ww2_prefix("ww2.");
+  if (host->compare(0, www_prefix.size(), www_prefix) == 0) {
+    host->erase(0, www_prefix.size());
+  } else if (host->compare(0, ww2_prefix.size(), ww2_prefix) == 0) {
+    host->erase(0, ww2_prefix.size());
+  }
+}
+
+}  // namespace
+
+namespace history_report {
+
+DeltaFileEntryWithData::DeltaFileEntryWithData(DeltaFileEntry entry)
+    : entry_(entry),
+      data_set_(false),
+      is_bookmark_(false) {}
+
+DeltaFileEntryWithData::~DeltaFileEntryWithData() {}
+
+int64 DeltaFileEntryWithData::SeqNo() const {
+  return entry_.seq_no();
+}
+
+std::string DeltaFileEntryWithData::Type() const {
+  // If deletion entry has data then it's not a real deletion entry
+  // but an update entry. Real deletion entry never has data.
+  if (data_set_) return "add";
+  return entry_.type();
+}
+
+// Generates a unique ID for a given URL.
+// It must be shorter than or equal to |kIdLengthLimit| characters.
+// If URL is shorter than or equal to |kIdLengthLimit| then ID is the URL
+// itself. Otherwise it has a form of 3 concatenated parts:
+//  1. Length of URL. Zero-padded integer to width |kUrlLengthWidth|,
+//     because URLs are limited to 20M in Chrome.
+//  2. SHA-256 of URL which takes 64 characters.
+//  3. Prefix of URL of size |kIdLengthLimit| - 64 - |kUrlLengthWidth|.
+std::string DeltaFileEntryWithData::UrlToId(const std::string& url) {
+  if (url.size() > kUrlLengthLimit) {
+    return "error: url too long";
+  }
+
+  if (IsValidId(url)) {
+    return url;
+  }
+
+  std::stringstream id;
+
+  // 1. Zero-padded URL length to width |kUrlLengthWidth|.
+  id << std::setfill('0') << std::setw(kUrlLengthWidth) << url.size();
+
+  // 2. SHA-256 of URL.
+  uint8 hash[kSHA256ByteSize];
+  crypto::SHA256HashString(url, hash, sizeof(hash));
+  id << base::HexEncode(hash, sizeof(hash));
+
+  // 3. Prefix of URL to fill rest of the space.
+  id << url.substr(0, kIdLengthLimit - 2 * kSHA256ByteSize - kUrlLengthWidth);
+
+  return id.str();
+}
+
+// ID which identifies URL of this entry.
+std::string DeltaFileEntryWithData::Id() const {
+  return UrlToId(entry_.url());
+}
+
+std::string DeltaFileEntryWithData::Url() const {
+  return entry_.url();
+}
+
+base::string16 DeltaFileEntryWithData::Title() const {
+  if (!Valid()) return base::UTF8ToUTF16("");
+  if (is_bookmark_ && !bookmark_title_.empty()) return bookmark_title_;
+  if (data_.title().empty()) return base::UTF8ToUTF16(data_.url().host());
+  return data_.title();
+}
+
+int32 DeltaFileEntryWithData::Score() const {
+  if (!Valid()) return 0;
+  int32 score = data_.visit_count() + data_.typed_count();
+  if (is_bookmark_) score = (score + 1) * kBookmarkScoreBonusMultiplier;
+  return score;
+}
+
+std::string DeltaFileEntryWithData::IndexedUrl() const {
+  if (!Valid()) return "";
+  std::string indexed_url = data_.url().host();
+  StripTopLevelDomain(&indexed_url);
+  StripCommonSubDomains(&indexed_url);
+  return indexed_url;
+}
+
+bool DeltaFileEntryWithData::Valid() const {
+  return entry_.type() == "del" || is_bookmark_ ||
+      (data_set_ && !data_.hidden());
+}
+
+void DeltaFileEntryWithData::SetData(const history::URLRow& data) {
+  data_set_ = true;
+  data_ = data;
+}
+
+void DeltaFileEntryWithData::MarkAsBookmark(
+    const BookmarkModel::URLAndTitle& bookmark) {
+  is_bookmark_ = true;
+  bookmark_title_ = bookmark.title;
+}
+
+// static
+bool DeltaFileEntryWithData::IsValidId(const std::string& url) {
+  return url.size() <= kIdLengthLimit;
+}
+
+}  // namespace history_report