[Sync] Move //sync to //components/sync.

sync/engine/get_commit_ids.cc

Index: sync/engine/get_commit_ids.cc
diff --git a/sync/engine/get_commit_ids.cc b/sync/engine/get_commit_ids.cc
deleted file mode 100644
index a4c7f6b7f7944f97b1c2b44a37af5115608e7aec..0000000000000000000000000000000000000000
--- a/sync/engine/get_commit_ids.cc
+++ /dev/null
@@ -1,590 +0,0 @@
-// Copyright 2013 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 "sync/engine/get_commit_ids.h"
-
-#include <stddef.h>
-#include <stdint.h>
-
-#include <set>
-#include <vector>
-
-#include "base/macros.h"
-#include "sync/engine/syncer_util.h"
-#include "sync/syncable/directory.h"
-#include "sync/syncable/entry.h"
-#include "sync/syncable/nigori_handler.h"
-#include "sync/syncable/nigori_util.h"
-#include "sync/syncable/syncable_base_transaction.h"
-#include "sync/syncable/syncable_util.h"
-#include "sync/util/cryptographer.h"
-
-using std::set;
-using std::vector;
-
-namespace syncer {
-
-namespace {
-
-// Forward-declare some helper functions.  This gives us more options for
-// ordering the function defintions within this file.
-
-// Filters |unsynced_handles| to remove all entries that do not belong to the
-// specified |requested_types|, or are not eligible for a commit at this time.
-void FilterUnreadyEntries(
-    syncable::BaseTransaction* trans,
-    ModelTypeSet requested_types,
-    ModelTypeSet encrypted_types,
-    bool passphrase_missing,
-    const syncable::Directory::Metahandles& unsynced_handles,
-    std::set<int64_t>* ready_unsynced_set);
-
-// Given a set of commit metahandles that are ready for commit
-// (|ready_unsynced_set|), sorts these into commit order and places up to
-// |max_entries| of them in the output parameter |out|.
-//
-// See the header file for an explanation of commit ordering.
-void OrderCommitIds(syncable::BaseTransaction* trans,
-                    size_t max_entries,
-                    const std::set<int64_t>& ready_unsynced_set,
-                    std::vector<int64_t>* out);
-
-}  // namespace
-
-void GetCommitIdsForType(
-    syncable::BaseTransaction* trans,
-    ModelType type,
-    size_t max_entries,
-    syncable::Directory::Metahandles* out) {
-  syncable::Directory* dir = trans->directory();
-
-  // Gather the full set of unsynced items and store it in the session. They
-  // are not in the correct order for commit.
-  std::set<int64_t> ready_unsynced_set;
-  syncable::Directory::Metahandles all_unsynced_handles;
-  GetUnsyncedEntries(trans, &all_unsynced_handles);
-
-  ModelTypeSet encrypted_types;
-  bool passphrase_missing = false;
-  Cryptographer* cryptographer = dir->GetCryptographer(trans);
-  if (cryptographer) {
-    encrypted_types = dir->GetNigoriHandler()->GetEncryptedTypes(trans);
-    passphrase_missing = cryptographer->has_pending_keys();
-  }
-
-  // We filter out all unready entries from the set of unsynced handles. This
-  // new set of ready and unsynced items is then what we use to determine what
-  // is a candidate for commit.  The caller is responsible for ensuring that no
-  // throttled types are included among the requested_types.
-  FilterUnreadyEntries(trans,
-                       ModelTypeSet(type),
-                       encrypted_types,
-                       passphrase_missing,
-                       all_unsynced_handles,
-                       &ready_unsynced_set);
-
-  OrderCommitIds(trans, max_entries, ready_unsynced_set, out);
-
-  for (size_t i = 0; i < out->size(); i++) {
-    DVLOG(1) << "Debug commit batch result:" << (*out)[i];
-  }
-}
-
-namespace {
-
-bool IsEntryInConflict(const syncable::Entry& entry) {
-  if (entry.GetIsUnsynced() &&
-      entry.GetServerVersion() > 0 &&
-      (entry.GetServerVersion() > entry.GetBaseVersion())) {
-    // The local and server versions don't match. The item must be in
-    // conflict, so there's no point in attempting to commit.
-    DCHECK(entry.GetIsUnappliedUpdate());
-    DVLOG(1) << "Excluding entry from commit due to version mismatch "
-             << entry;
-    return true;
-  }
-  return false;
-}
-
-// Return true if this entry has any attachments that haven't yet been uploaded
-// to the server.
-bool HasAttachmentNotOnServer(const syncable::Entry& entry) {
-  const sync_pb::AttachmentMetadata& metadata = entry.GetAttachmentMetadata();
-  for (int i = 0; i < metadata.record_size(); ++i) {
-    if (!metadata.record(i).is_on_server()) {
-      return true;
-    }
-  }
-  return false;
-}
-
-// An entry may not commit if any are true:
-// 1. It requires encryption (either the type is encrypted but a passphrase
-//    is missing from the cryptographer, or the entry itself wasn't properly
-//    encrypted).
-// 2. It's type is currently throttled.
-// 3. It's a delete but has not been committed.
-bool MayEntryCommit(ModelTypeSet requested_types,
-                    ModelTypeSet encrypted_types,
-                    bool passphrase_missing,
-                    const syncable::Entry& entry) {
-  DCHECK(entry.GetIsUnsynced());
-
-  const ModelType type = entry.GetModelType();
-  // We special case the nigori node because even though it is considered an
-  // "encrypted type", not all nigori node changes require valid encryption
-  // (ex: sync_tabs).
-  if ((type != NIGORI) && encrypted_types.Has(type) &&
-      (passphrase_missing ||
-       syncable::EntryNeedsEncryption(encrypted_types, entry))) {
-    // This entry requires encryption but is not properly encrypted (possibly
-    // due to the cryptographer not being initialized or the user hasn't
-    // provided the most recent passphrase).
-    DVLOG(1) << "Excluding entry from commit due to lack of encryption "
-             << entry;
-    return false;
-  }
-
-  // Ignore it if it's not in our set of requested types.
-  if (!requested_types.Has(type))
-    return false;
-
-  if (entry.GetIsDel() && !entry.GetId().ServerKnows()) {
-    // New clients (following the resolution of crbug.com/125381) should not
-    // create such items.  Old clients may have left some in the database
-    // (crbug.com/132905), but we should now be cleaning them on startup.
-    NOTREACHED() << "Found deleted and unsynced local item: " << entry;
-    return false;
-  }
-
-  // Extra validity checks.
-  syncable::Id id = entry.GetId();
-  if (id == entry.GetParentId()) {
-    CHECK(id.IsRoot()) << "Non-root item is self parenting." << entry;
-    // If the root becomes unsynced it can cause us problems.
-    NOTREACHED() << "Root item became unsynced " << entry;
-    return false;
-  }
-
-  if (entry.IsRoot()) {
-    NOTREACHED() << "Permanent item became unsynced " << entry;
-    return false;
-  }
-
-  if (HasAttachmentNotOnServer(entry)) {
-    // This entry is not ready to be sent to the server because it has one or
-    // more attachments that have not yet been uploaded to the server.  The idea
-    // here is avoid propagating an entry with dangling attachment references.
-    return false;
-  }
-
-  DVLOG(2) << "Entry is ready for commit: " << entry;
-  return true;
-}
-
-bool SupportsHierarchy(const syncable::Entry& item) {
-  // Types with explicit server supported hierarchy only.
-  return IsTypeWithServerGeneratedRoot(item.GetModelType());
-}
-
-// Excludes ancestors of deleted conflicted items from
-// |ready_unsynced_set|.
-void ExcludeDeletedAncestors(
-    syncable::BaseTransaction* trans,
-    const std::vector<int64_t>& deleted_conflicted_items,
-    std::set<int64_t>* ready_unsynced_set) {
-  for (auto iter = deleted_conflicted_items.begin();
-       iter != deleted_conflicted_items.end(); ++iter) {
-    syncable::Entry item(trans, syncable::GET_BY_HANDLE, *iter);
-    syncable::Id parent_id = item.GetParentId();
-    DCHECK(!parent_id.IsNull());
-
-    while (!parent_id.IsRoot()) {
-      syncable::Entry parent(trans, syncable::GET_BY_ID, parent_id);
-      CHECK(parent.good()) << "Bad user-only parent in item path.";
-      int64_t handle = parent.GetMetahandle();
-
-      if (!parent.GetIsDel())
-        break;
-
-      auto ready_iter = ready_unsynced_set->find(handle);
-      if (ready_iter == ready_unsynced_set->end())
-        break;
-
-      // Remove this entry from |ready_unsynced_set|.
-      ready_unsynced_set->erase(ready_iter);
-      parent_id = parent.GetParentId();
-    }
-  }
-}
-
-// Iterates over children of items from |conflicted_items| list that are in
-// |ready_unsynced_set|, exludes them from |ready_unsynced_set| and adds them
-// to |excluded_items| list.
-void ExcludeChildren(syncable::BaseTransaction* trans,
-                     const std::vector<int64_t>& conflicted_items,
-                     std::vector<int64_t>* excluded_items,
-                     std::set<int64_t>* ready_unsynced_set) {
-  for (auto iter = conflicted_items.begin(); iter != conflicted_items.end();
-       ++iter) {
-    syncable::Entry entry(trans, syncable::GET_BY_HANDLE, *iter);
-
-    if (!entry.GetIsDir() || entry.GetIsDel())
-      continue;
-
-    std::vector<int64_t> children;
-    entry.GetChildHandles(&children);
-
-    for (std::vector<int64_t>::const_iterator child_iter = children.begin();
-         child_iter != children.end(); ++child_iter) {
-      // Collect all child handles that are in |ready_unsynced_set|.
-      int64_t child_handle = *child_iter;
-      auto ready_iter = ready_unsynced_set->find(child_handle);
-      if (ready_iter != ready_unsynced_set->end()) {
-        // Remove this entry from |ready_unsynced_set| and add it
-        // to |excluded_items|.
-        ready_unsynced_set->erase(ready_iter);
-        excluded_items->push_back(child_handle);
-      }
-    }
-  }
-}
-
-// Filters |unsynced_handles| to remove all entries that do not belong to the
-// specified |requested_types|, or are not eligible for a commit at this time.
-void FilterUnreadyEntries(
-    syncable::BaseTransaction* trans,
-    ModelTypeSet requested_types,
-    ModelTypeSet encrypted_types,
-    bool passphrase_missing,
-    const syncable::Directory::Metahandles& unsynced_handles,
-    std::set<int64_t>* ready_unsynced_set) {
-  std::vector<int64_t> deleted_conflicted_items;
-  std::vector<int64_t> conflicted_items;
-
-  // Go over all unsynced handles, filter the ones that might be committed based
-  // on type / encryption, then based on whether they are in conflict add them
-  // to either |ready_unsynced_set| or one of the conflicted lists.
-  for (auto iter = unsynced_handles.begin(); iter != unsynced_handles.end();
-       ++iter) {
-    syncable::Entry entry(trans, syncable::GET_BY_HANDLE, *iter);
-    // TODO(maniscalco): While we check if entry is ready to be committed, we
-    // also need to check that all of its ancestors (parents, transitive) are
-    // ready to be committed.  Once attachments can prevent an entry from being
-    // committable, this method must ensure all ancestors are ready for commit
-    // (bug 356273).
-    if (MayEntryCommit(requested_types, encrypted_types, passphrase_missing,
-                       entry)) {
-      if (IsEntryInConflict(entry)) {
-        // Conflicting hierarchical entries might prevent their ancestors or
-        // descendants from being committed.
-        if (SupportsHierarchy(entry)) {
-          if (entry.GetIsDel()) {
-            deleted_conflicted_items.push_back(*iter);
-          } else if (entry.GetIsDir()) {
-            // Populate the initial version of |conflicted_items| with folder
-            // items that are in conflict.
-            conflicted_items.push_back(*iter);
-          }
-        }
-      } else {
-        ready_unsynced_set->insert(*iter);
-      }
-    }
-  }
-
-  // If there are any deleted conflicted entries, remove their deleted ancestors
-  // from |ready_unsynced_set| as well.
-  ExcludeDeletedAncestors(trans, deleted_conflicted_items, ready_unsynced_set);
-
-  // Starting with conflicted_items containing conflicted folders go down and
-  // exclude all descendants from |ready_unsynced_set|.
-  while (!conflicted_items.empty()) {
-    std::vector<int64_t> new_list;
-    ExcludeChildren(trans, conflicted_items, &new_list, ready_unsynced_set);
-    conflicted_items.swap(new_list);
-  }
-}
-
-// This class helps to implement OrderCommitIds().  Its members track the
-// progress of a traversal while its methods extend it.  It can return early if
-// the traversal reaches the desired size before the full traversal is complete.
-class Traversal {
- public:
-  Traversal(syncable::BaseTransaction* trans,
-            int64_t max_entries,
-            syncable::Directory::Metahandles* out);
-  ~Traversal();
-
-  // First step of traversal building.  Adds non-deleted items in order.
-  void AddCreatesAndMoves(const std::set<int64_t>& ready_unsynced_set);
-
-  // Second step of traverals building.  Appends deleted items.
-  void AddDeletes(const std::set<int64_t>& ready_unsynced_set);
-
- private:
-  // The following functions do not modify the traversal directly.  They return
-  // their results in the |result| vector instead.
-  void AddUncommittedParents(const std::set<int64_t>& ready_unsynced_set,
-                             const syncable::Entry& item,
-                             syncable::Directory::Metahandles* result) const;
-
-  bool TryAddItem(const std::set<int64_t>& ready_unsynced_set,
-                  const syncable::Entry& item,
-                  syncable::Directory::Metahandles* result) const;
-
-  void AddDeletedParents(const std::set<int64_t>& ready_unsynced_set,
-                         const syncable::Entry& item,
-                         const syncable::Directory::Metahandles& traversed,
-                         syncable::Directory::Metahandles* result) const;
-
-  // Returns true if we've collected enough items.
-  bool IsFull() const;
-
-  // Returns true if the specified handle is already in the traversal.
-  bool HaveItem(int64_t handle) const;
-
-  // Adds the specified handles to the traversal.
-  void AppendManyToTraversal(const syncable::Directory::Metahandles& handles);
-
-  // Adds the specifed handle to the traversal.
-  void AppendToTraversal(int64_t handle);
-
-  syncable::Directory::Metahandles* out_;
-  std::set<int64_t> added_handles_;
-  const size_t max_entries_;
-  syncable::BaseTransaction* trans_;
-
-  DISALLOW_COPY_AND_ASSIGN(Traversal);
-};
-
-Traversal::Traversal(syncable::BaseTransaction* trans,
-                     int64_t max_entries,
-                     syncable::Directory::Metahandles* out)
-    : out_(out), max_entries_(max_entries), trans_(trans) {}
-
-Traversal::~Traversal() {}
-
-void Traversal::AddUncommittedParents(
-    const std::set<int64_t>& ready_unsynced_set,
-    const syncable::Entry& item,
-    syncable::Directory::Metahandles* result) const {
-  DCHECK(SupportsHierarchy(item));
-  syncable::Directory::Metahandles dependencies;
-  syncable::Id parent_id = item.GetParentId();
-
-  // Climb the tree adding entries leaf -> root.
-  while (!parent_id.ServerKnows()) {
-    syncable::Entry parent(trans_, syncable::GET_BY_ID, parent_id);
-    CHECK(parent.good()) << "Bad user-only parent in item path.";
-    int64_t handle = parent.GetMetahandle();
-    if (HaveItem(handle)) {
-      // We've already added this parent (and therefore all of its parents).
-      // We can return early.
-      break;
-    }
-
-    if (!TryAddItem(ready_unsynced_set, parent, &dependencies)) {
-      // The parent isn't in |ready_unsynced_set|.
-      break;
-    }
-
-    parent_id = parent.GetParentId();
-  }
-
-  // Reverse what we added to get the correct order.
-  result->insert(result->end(), dependencies.rbegin(), dependencies.rend());
-}
-
-// Adds the given item to the list if it is unsynced and ready for commit.
-bool Traversal::TryAddItem(const std::set<int64_t>& ready_unsynced_set,
-                           const syncable::Entry& item,
-                           syncable::Directory::Metahandles* result) const {
-  DCHECK(item.GetIsUnsynced());
-  int64_t item_handle = item.GetMetahandle();
-  if (ready_unsynced_set.count(item_handle) != 0) {
-    result->push_back(item_handle);
-    return true;
-  }
-  return false;
-}
-
-// Traverses the tree from bottom to top, adding the deleted parents of the
-// given |item|.  Stops traversing if it encounters a non-deleted node, or
-// a node that was already listed in the |traversed| list.
-//
-// The result list is reversed before it is returned, so the resulting
-// traversal is in top to bottom order.  Also note that this function appends
-// to the result list without clearing it.
-void Traversal::AddDeletedParents(
-    const std::set<int64_t>& ready_unsynced_set,
-    const syncable::Entry& item,
-    const syncable::Directory::Metahandles& traversed,
-    syncable::Directory::Metahandles* result) const {
-  DCHECK(SupportsHierarchy(item));
-  syncable::Directory::Metahandles dependencies;
-  syncable::Id parent_id = item.GetParentId();
-
-  // Climb the tree adding entries leaf -> root.
-  while (!parent_id.IsRoot()) {
-    syncable::Entry parent(trans_, syncable::GET_BY_ID, parent_id);
-
-    if (!parent.good()) {
-      // This is valid because the parent could have gone away a long time ago
-      //
-      // Consider the case where a folder is server-unknown and locally
-      // deleted, and has a child that is server-known, deleted, and unsynced.
-      // The parent could be dropped from memory at any time, but its child
-      // needs to be committed first.
-      break;
-    }
-    int64_t handle = parent.GetMetahandle();
-    if (!parent.GetIsUnsynced()) {
-      // In some rare cases, our parent can be both deleted and unsynced.
-      // (ie. the server-unknown parent case).
-      break;
-    }
-    if (!parent.GetIsDel()) {
-      // We're not intersted in non-deleted parents.
-      break;
-    }
-    if (std::find(traversed.begin(), traversed.end(), handle) !=
-        traversed.end()) {
-      // We've already added this parent (and therefore all of its parents).
-      // We can return early.
-      break;
-    }
-
-    if (!TryAddItem(ready_unsynced_set, parent, &dependencies)) {
-      // The parent isn't in ready_unsynced_set.
-      break;
-    }
-
-    parent_id = parent.GetParentId();
-  }
-
-  // Reverse what we added to get the correct order.
-  result->insert(result->end(), dependencies.rbegin(), dependencies.rend());
-}
-
-bool Traversal::IsFull() const {
-  return out_->size() >= max_entries_;
-}
-
-bool Traversal::HaveItem(int64_t handle) const {
-  return added_handles_.find(handle) != added_handles_.end();
-}
-
-void Traversal::AppendManyToTraversal(
-    const syncable::Directory::Metahandles& handles) {
-  out_->insert(out_->end(), handles.begin(), handles.end());
-  added_handles_.insert(handles.begin(), handles.end());
-}
-
-void Traversal::AppendToTraversal(int64_t metahandle) {
-  out_->push_back(metahandle);
-  added_handles_.insert(metahandle);
-}
-
-void Traversal::AddCreatesAndMoves(
-    const std::set<int64_t>& ready_unsynced_set) {
-  // Add moves and creates, and prepend their uncommitted parents.
-  for (std::set<int64_t>::const_iterator iter = ready_unsynced_set.begin();
-       !IsFull() && iter != ready_unsynced_set.end(); ++iter) {
-    int64_t metahandle = *iter;
-    if (HaveItem(metahandle))
-      continue;
-
-    syncable::Entry entry(trans_,
-                          syncable::GET_BY_HANDLE,
-                          metahandle);
-    if (!entry.GetIsDel()) {
-      if (SupportsHierarchy(entry)) {
-        // We only commit an item + its dependencies if it and all its
-        // dependencies are not in conflict.
-        syncable::Directory::Metahandles item_dependencies;
-        AddUncommittedParents(ready_unsynced_set, entry, &item_dependencies);
-        TryAddItem(ready_unsynced_set, entry, &item_dependencies);
-        AppendManyToTraversal(item_dependencies);
-      } else {
-        // No hierarchy dependencies, just commit the item itself.
-        AppendToTraversal(metahandle);
-      }
-    }
-  }
-
-  // It's possible that we overcommitted while trying to expand dependent
-  // items.  If so, truncate the set down to the allowed size.
-  if (out_->size() > max_entries_)
-    out_->resize(max_entries_);
-}
-
-void Traversal::AddDeletes(const std::set<int64_t>& ready_unsynced_set) {
-  syncable::Directory::Metahandles deletion_list;
-
-  // Note: we iterate over all the unsynced set, regardless of the max size.
-  // The max size is only enforced after the top-to-bottom order has been
-  // reversed, in order to ensure children are always deleted before parents.
-  for (std::set<int64_t>::const_iterator iter = ready_unsynced_set.begin();
-       iter != ready_unsynced_set.end(); ++iter) {
-    int64_t metahandle = *iter;
-
-    if (HaveItem(metahandle))
-      continue;
-
-    if (std::find(deletion_list.begin(), deletion_list.end(), metahandle) !=
-        deletion_list.end()) {
-      continue;
-    }
-
-    syncable::Entry entry(trans_, syncable::GET_BY_HANDLE,
-                          metahandle);
-
-    if (entry.GetIsDel()) {
-      if (SupportsHierarchy(entry)) {
-        syncable::Directory::Metahandles parents;
-        AddDeletedParents(ready_unsynced_set, entry, deletion_list, &parents);
-        // Append parents and chilren in top to bottom order.
-        deletion_list.insert(deletion_list.end(), parents.begin(),
-                             parents.end());
-      }
-      deletion_list.push_back(metahandle);
-    }
-  }
-
-  // We've been gathering deletions in top to bottom order.  Now we reverse the
-  // order as we prepare the list.
-  std::reverse(deletion_list.begin(), deletion_list.end());
-  AppendManyToTraversal(deletion_list);
-
-  // It's possible that we overcommitted while trying to expand dependent
-  // items.  If so, truncate the set down to the allowed size.
-  if (out_->size() > max_entries_)
-    out_->resize(max_entries_);
-}
-
-void OrderCommitIds(syncable::BaseTransaction* trans,
-                    size_t max_entries,
-                    const std::set<int64_t>& ready_unsynced_set,
-                    syncable::Directory::Metahandles* out) {
-  // Commits follow these rules:
-  // 1. Moves or creates are preceded by needed folder creates, from
-  //    root to leaf.
-  // 2. Moves/Creates before deletes.
-  // 3. Deletes, collapsed.
-  // We commit deleted moves under deleted items as moves when collapsing
-  // delete trees.
-
-  Traversal traversal(trans, max_entries, out);
-
-  // Add moves and creates, and prepend their uncommitted parents.
-  traversal.AddCreatesAndMoves(ready_unsynced_set);
-
-  // Add all deletes.
-  traversal.AddDeletes(ready_unsynced_set);
-}
-
-}  // namespace
-
-}  // namespace syncer