Import the archivist framework.

Author: chinmaygarde

impeller/BUILD.gn

@@ -9,6 +9,7 @@ config("impeller_public_config") {
 group("impeller") {
   public_deps = [
     "aiks",
+    "archivist",
     "base",
     "compiler",
     "display_list",
@@ -24,6 +25,7 @@ executable("impeller_unittests") {
 
   deps = [
     "aiks:aiks_unittests",
+    "archivist:archivist_unittests",
     "base:base_unittests",
     "compiler:compiler_unittests",
     "display_list:display_list_unittests",

impeller/archivist/BUILD.gn

@@ -0,0 +1,39 @@
+# Copyright 2013 The Flutter Authors. All rights reserved.
+# Use of this source code is governed by a BSD-style license that can be
+# found in the LICENSE file.
+
+import("../tools/impeller.gni")
+
+impeller_component("archivist") {
+  # Only the umbrella header is public since all other TU's are implementation
+  # detail that will be compiled away in release modes.
+  # Because they are implementation details, they may expose dependency headers.
+  public = [ "archive.h" ]
+
+  sources = [
+    "archive.cc",
+    "archive_class_registration.cc",
+    "archive_class_registration.h",
+    "archive_database.cc",
+    "archive_database.h",
+    "archive_statement.cc",
+    "archive_statement.h",
+    "archive_transaction.cc",
+    "archive_transaction.h",
+    "archive_vector.cc",
+    "archive_vector.h",
+  ]
+
+  public_deps = [ "../base" ]
+
+  deps = [ "//third_party/sqlite" ]
+}
+
+impeller_component("archivist_unittests") {
+  testonly = true
+  sources = [ "archivist_unittests.cc" ]
+  deps = [
+    ":archivist",
+    "//flutter/testing",
+  ]
+}

impeller/archivist/archive.cc

@@ -0,0 +1,317 @@
+// Copyright 2013 The Flutter 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 "impeller/archivist/archive.h"
+
+#include <iterator>
+
+#include "flutter/fml/logging.h"
+#include "impeller/archivist/archive_class_registration.h"
+#include "impeller/archivist/archive_database.h"
+#include "impeller/archivist/archive_statement.h"
+#include "impeller/archivist/archive_vector.h"
+
+namespace impeller {
+
+Archive::Archive(const std::string& path, bool recreate)
+    : _db(std::make_unique<ArchiveDatabase>(path, recreate)) {}
+
+Archive::~Archive() {
+  FML_DCHECK(_transactionCount == 0) << "There must be no pending transactions";
+}
+
+bool Archive::isReady() const {
+  return _db->isReady();
+}
+
+bool Archive::archiveInstance(const ArchiveDef& definition,
+                              const ArchiveSerializable& archivable,
+                              int64_t& lastInsertIDOut) {
+  if (!isReady()) {
+    return false;
+  }
+
+  auto transaction = _db->acquireTransaction(_transactionCount);
+
+  const auto* registration = _db->registrationForDefinition(definition);
+
+  if (registration == nullptr) {
+    return false;
+  }
+
+  auto statement = registration->insertStatement();
+
+  if (!statement.isReady() || !statement.reset()) {
+    /*
+     *  Must be able to reset the statement for a new write
+     */
+    return false;
+  }
+
+  auto itemName = archivable.archiveName();
+
+  /*
+   *  The lifecycle of the archive item is tied to this scope and there is no
+   *  way for the user to create an instance of an archive item. So its safe
+   *  for its members to be references. It does not manage the lifetimes of
+   *  anything.
+   */
+  ArchiveItem item(*this, statement, *registration, itemName);
+
+  /*
+   *  We need to bind the primary key only if the item does not provide its own
+   */
+  if (!definition.autoAssignName &&
+      !statement.bind(ArchiveClassRegistration::NameIndex, itemName)) {
+    return false;
+  }
+
+  if (!archivable.serialize(item)) {
+    return false;
+  }
+
+  if (statement.run() != ArchiveStatement::Result::Done) {
+    return false;
+  }
+
+  int64_t lastInsert = _db->lastInsertRowID();
+
+  if (!definition.autoAssignName &&
+      lastInsert != static_cast<int64_t>(itemName)) {
+    return false;
+  }
+
+  lastInsertIDOut = lastInsert;
+
+  /*
+   *  If any of the nested calls fail, we would have already checked for the
+   *  failure and returned.
+   */
+  transaction.markWritesSuccessful();
+
+  return true;
+}
+
+bool Archive::unarchiveInstance(const ArchiveDef& definition,
+                                ArchiveSerializable::ArchiveName name,
+                                ArchiveSerializable& archivable) {
+  UnarchiveStep stepper = [&archivable](ArchiveItem& item) {
+    archivable.deserialize(item);
+    return false /* no-more after single read */;
+  };
+
+  return unarchiveInstances(definition, stepper, name) == 1;
+}
+
+size_t Archive::unarchiveInstances(const ArchiveDef& definition,
+                                   Archive::UnarchiveStep stepper,
+                                   ArchiveSerializable::ArchiveName name) {
+  if (!isReady()) {
+    return 0;
+  }
+
+  const auto* registration = _db->registrationForDefinition(definition);
+
+  if (registration == nullptr) {
+    return 0;
+  }
+
+  const bool isQueryingSingle = name != ArchiveNameAuto;
+
+  auto statement = registration->queryStatement(isQueryingSingle);
+
+  if (!statement.isReady() || !statement.reset()) {
+    return 0;
+  }
+
+  if (isQueryingSingle) {
+    /*
+     *  If a single statement is being queried for, bind the name as a statement
+     *  argument.
+     */
+    if (!statement.bind(ArchiveClassRegistration::NameIndex, name)) {
+      return 0;
+    }
+  }
+
+  if (statement.columnCount() !=
+      registration->memberCount() + 1 /* primary key */) {
+    return 0;
+  }
+
+  /*
+   *  Acquire a transaction but never mark it successful since we will never
+   *  be committing any writes to the database during unarchiving.
+   */
+  auto transaction = _db->acquireTransaction(_transactionCount);
+
+  size_t itemsRead = 0;
+
+  while (statement.run() == ArchiveStatement::Result::Row) {
+    itemsRead++;
+
+    /*
+     *  Prepare a fresh archive item for the given statement
+     */
+    ArchiveItem item(*this, statement, *registration, name);
+
+    if (!stepper(item)) {
+      break;
+    }
+
+    if (isQueryingSingle) {
+      break;
+    }
+  }
+
+  return itemsRead;
+}
+
+ArchiveItem::ArchiveItem(Archive& context,
+                         ArchiveStatement& statement,
+                         const ArchiveClassRegistration& registration,
+                         ArchiveSerializable::ArchiveName name)
+    : _context(context),
+      _statement(statement),
+      _registration(registration),
+      _name(name),
+      _currentClass(registration.className()) {}
+
+ArchiveSerializable::ArchiveName ArchiveItem::name() const {
+  return _name;
+}
+
+bool ArchiveItem::encode(ArchiveSerializable::Member member,
+                         const std::string& item) {
+  auto found = _registration.findColumn(_currentClass, member);
+  return found.second ? _statement.bind(found.first, item) : false;
+}
+
+bool ArchiveItem::encodeIntegral(ArchiveSerializable::Member member,
+                                 int64_t item) {
+  auto found = _registration.findColumn(_currentClass, member);
+  return found.second ? _statement.bind(found.first, item) : false;
+}
+
+bool ArchiveItem::encode(ArchiveSerializable::Member member, double item) {
+  auto found = _registration.findColumn(_currentClass, member);
+  return found.second ? _statement.bind(found.first, item) : false;
+}
+
+bool ArchiveItem::encode(ArchiveSerializable::Member member,
+                         const Allocation& item) {
+  auto found = _registration.findColumn(_currentClass, member);
+  return found.second ? _statement.bind(found.first, item) : false;
+}
+
+bool ArchiveItem::encode(ArchiveSerializable::Member member,
+                         const ArchiveDef& otherDef,
+                         const ArchiveSerializable& other) {
+  auto found = _registration.findColumn(_currentClass, member);
+
+  if (!found.second) {
+    return false;
+  }
+
+  /*
+   *  We need to fully archive the other instance first because it could
+   *  have a name that is auto assigned. In that case, we cannot ask it before
+   *  archival (via `other.archiveName()`).
+   */
+  int64_t lastInsert = 0;
+  if (!_context.archiveInstance(otherDef, other, lastInsert)) {
+    return false;
+  }
+
+  /*
+   *  Bind the name of the serialiable
+   */
+  if (!_statement.bind(found.first, lastInsert)) {
+    return false;
+  }
+
+  return true;
+}
+
+std::pair<bool, int64_t> ArchiveItem::encodeVectorKeys(
+    std::vector<int64_t>&& members) {
+  ArchiveVector vector(std::move(members));
+  int64_t vectorID = 0;
+  if (!_context.archiveInstance(ArchiveVector::ArchiveDefinition,  //
+                                vector,                            //
+                                vectorID)) {
+    return {false, 0};
+  }
+  return {true, vectorID};
+}
+
+bool ArchiveItem::decodeVectorKeys(ArchiveSerializable::ArchiveName name,
+                                   std::vector<int64_t>& members) {
+  ArchiveVector vector;
+
+  if (!_context.unarchiveInstance(ArchiveVector::ArchiveDefinition, name,
+                                  vector)) {
+    return false;
+  }
+
+  const auto& keys = vector.keys();
+
+  std::move(keys.begin(), keys.end(), std::back_inserter(members));
+
+  return true;
+}
+
+bool ArchiveItem::decode(ArchiveSerializable::Member member,
+                         std::string& item) {
+  auto found = _registration.findColumn(_currentClass, member);
+  return found.second ? _statement.column(found.first, item) : false;
+}
+
+bool ArchiveItem::decodeIntegral(ArchiveSerializable::Member member,
+                                 int64_t& item) {
+  auto found = _registration.findColumn(_currentClass, member);
+  return found.second ? _statement.column(found.first, item) : false;
+}
+
+bool ArchiveItem::decode(ArchiveSerializable::Member member, double& item) {
+  auto found = _registration.findColumn(_currentClass, member);
+  return found.second ? _statement.column(found.first, item) : false;
+}
+
+bool ArchiveItem::decode(ArchiveSerializable::Member member, Allocation& item) {
+  auto found = _registration.findColumn(_currentClass, member);
+  return found.second ? _statement.column(found.first, item) : false;
+}
+
+bool ArchiveItem::decode(ArchiveSerializable::Member member,
+                         const ArchiveDef& otherDef,
+                         ArchiveSerializable& other) {
+  auto found = _registration.findColumn(_currentClass, member);
+
+  /*
+   *  Make sure a member is present at that column
+   */
+  if (!found.second) {
+    return false;
+  }
+
+  /*
+   *  Try to find the foreign key in the current items row
+   */
+  int64_t foreignKey = 0;
+  if (!_statement.column(found.first, foreignKey)) {
+    return false;
+  }
+
+  /*
+   *  Find the other item and unarchive by this foreign key
+   */
+  if (!_context.unarchiveInstance(otherDef, foreignKey, other)) {
+    return false;
+  }
+
+  return true;
+}
+
+}  // namespace impeller