Migrate the IndexedDB backend from Blink to Chromium

content/browser/indexed_db/indexed_db_cursor_impl.cc

+// Copyright (c) 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 "content/browser/indexed_db/indexed_db_cursor_impl.h"
+
+#include "base/logging.h"
+#include "content/browser/indexed_db/indexed_db_backing_store.h"
+#include "content/browser/indexed_db/indexed_db_callbacks_wrapper.h"
+#include "content/browser/indexed_db/indexed_db_database_error.h"
+#include "content/browser/indexed_db/indexed_db_database_impl.h"
+#include "content/browser/indexed_db/indexed_db_tracing.h"
+#include "content/browser/indexed_db/indexed_db_transaction.h"
+#include "content/common/indexed_db/indexed_db_key_range.h"
+
+namespace content {
+
+class IndexedDBCursorImpl::CursorIterationOperation
+    : public IndexedDBTransaction::Operation {
+ public:
+  CursorIterationOperation(scoped_refptr<IndexedDBCursorImpl> cursor,
+                           scoped_ptr<IndexedDBKey> key,
+                           scoped_refptr<IndexedDBCallbacksWrapper> callbacks)
+      : cursor_(cursor), key_(key.Pass()), callbacks_(callbacks) {}
+  virtual void Perform(IndexedDBTransaction* transaction) OVERRIDE;
+
+ private:
+  scoped_refptr<IndexedDBCursorImpl> cursor_;
+  scoped_ptr<IndexedDBKey> key_;
+  scoped_refptr<IndexedDBCallbacksWrapper> callbacks_;
+};
+
+class IndexedDBCursorImpl::CursorAdvanceOperation
+    : public IndexedDBTransaction::Operation {
+ public:
+  CursorAdvanceOperation(scoped_refptr<IndexedDBCursorImpl> cursor,
+                         unsigned long count,
+                         scoped_refptr<IndexedDBCallbacksWrapper> callbacks)
+      : cursor_(cursor), count_(count), callbacks_(callbacks) {}
+  virtual void Perform(IndexedDBTransaction* transaction) OVERRIDE;
+
+ private:
+  scoped_refptr<IndexedDBCursorImpl> cursor_;
+  unsigned long count_;
+  scoped_refptr<IndexedDBCallbacksWrapper> callbacks_;
+};
+
+class IndexedDBCursorImpl::CursorPrefetchIterationOperation
+    : public IndexedDBTransaction::Operation {
+ public:
+  CursorPrefetchIterationOperation(
+      scoped_refptr<IndexedDBCursorImpl> cursor,
+      int number_to_fetch,
+      scoped_refptr<IndexedDBCallbacksWrapper> callbacks)
+      : cursor_(cursor),
+        number_to_fetch_(number_to_fetch),
+        callbacks_(callbacks) {}
+  virtual void Perform(IndexedDBTransaction* transaction) OVERRIDE;
+
+ private:
+  scoped_refptr<IndexedDBCursorImpl> cursor_;
+  int number_to_fetch_;
+  scoped_refptr<IndexedDBCallbacksWrapper> callbacks_;
+};
+
+IndexedDBCursorImpl::IndexedDBCursorImpl(
+    scoped_ptr<IndexedDBBackingStore::Cursor> cursor,
+    indexed_db::CursorType cursor_type,
+    IndexedDBDatabase::TaskType task_type,
+    IndexedDBTransaction* transaction,
+    int64 object_store_id)
+    : task_type_(task_type),
+      cursor_type_(cursor_type),
+      transaction_(transaction),
+      object_store_id_(object_store_id),
+      cursor_(cursor.Pass()),
+      closed_(false) {
+  transaction_->RegisterOpenCursor(this);
+}
+
+IndexedDBCursorImpl::~IndexedDBCursorImpl() {
+  transaction_->UnregisterOpenCursor(this);
+}
+
+void IndexedDBCursorImpl::ContinueFunction(
+    scoped_ptr<IndexedDBKey> key,
+    scoped_refptr<IndexedDBCallbacksWrapper> callbacks) {
+  IDB_TRACE("IndexedDBCursorImpl::continue");
+
+  transaction_->ScheduleTask(
+      task_type_, new CursorIterationOperation(this, key.Pass(), callbacks));
+}
+
+void IndexedDBCursorImpl::Advance(
+    unsigned long count,
+    scoped_refptr<IndexedDBCallbacksWrapper> callbacks) {
+  IDB_TRACE("IndexedDBCursorImpl::advance");
+
+  transaction_->ScheduleTask(
+      new CursorAdvanceOperation(this, count, callbacks));
+}
+
+void IndexedDBCursorImpl::CursorAdvanceOperation::Perform(
+    IndexedDBTransaction* /*transaction*/) {
+  IDB_TRACE("CursorAdvanceOperation");
+  if (!cursor_->cursor_ || !cursor_->cursor_->Advance(count_)) {
+    cursor_->cursor_.reset();
+    callbacks_->OnSuccess(static_cast<std::vector<char>*>(NULL));
+    return;
+  }
+
+  callbacks_->OnSuccess(
+      cursor_->key(), cursor_->primary_key(), cursor_->Value());
+}
+
+void IndexedDBCursorImpl::CursorIterationOperation::Perform(
+    IndexedDBTransaction* /*transaction*/) {
+  IDB_TRACE("CursorIterationOperation");
+  if (!cursor_->cursor_ || !cursor_->cursor_->ContinueFunction(key_.get())) {
+    cursor_->cursor_.reset();
+    callbacks_->OnSuccess(static_cast<std::vector<char>*>(NULL));
+    return;
+  }
+
+  callbacks_->OnSuccess(
+      cursor_->key(), cursor_->primary_key(), cursor_->Value());
+}
+
+void IndexedDBCursorImpl::DeleteFunction(
+    scoped_refptr<IndexedDBCallbacksWrapper> callbacks) {
+  IDB_TRACE("IndexedDBCursorImpl::delete");
+  DCHECK_NE(transaction_->mode(), indexed_db::TRANSACTION_READ_ONLY);
+  scoped_ptr<IndexedDBKeyRange> key_range =
+      make_scoped_ptr(new IndexedDBKeyRange(cursor_->primary_key()));
+  transaction_->database()->DeleteRange(
+      transaction_->id(), object_store_id_, key_range.Pass(), callbacks);
+}
+
+void IndexedDBCursorImpl::PrefetchContinue(
+    int number_to_fetch,
+    scoped_refptr<IndexedDBCallbacksWrapper> callbacks) {
+  IDB_TRACE("IndexedDBCursorImpl::prefetch_continue");
+
+  transaction_->ScheduleTask(
+      task_type_,
+      new CursorPrefetchIterationOperation(this, number_to_fetch, callbacks));
+}
+
+void IndexedDBCursorImpl::CursorPrefetchIterationOperation::Perform(
+    IndexedDBTransaction* /*transaction*/) {
+  IDB_TRACE("CursorPrefetchIterationOperation");
+
+  std::vector<IndexedDBKey> found_keys;
+  std::vector<IndexedDBKey> found_primary_keys;
+  std::vector<std::vector<char> > found_values;
+
+  if (cursor_->cursor_)
+    cursor_->saved_cursor_.reset(cursor_->cursor_->Clone());
+  const size_t max_size_estimate = 10 * 1024 * 1024;
+  size_t size_estimate = 0;
+
+  for (int i = 0; i < number_to_fetch_; ++i) {
+    if (!cursor_->cursor_ || !cursor_->cursor_->ContinueFunction(0)) {
+      cursor_->cursor_.reset();
+      break;
+    }
+
+    found_keys.push_back(cursor_->cursor_->key());
+    found_primary_keys.push_back(cursor_->cursor_->primary_key());
+
+    switch (cursor_->cursor_type_) {
+      case indexed_db::CURSOR_KEY_ONLY:
+        found_values.push_back(std::vector<char>());
+        break;
+      case indexed_db::CURSOR_KEY_AND_VALUE: {
+        std::vector<char> value;
+        value.swap(*cursor_->cursor_->Value());
+        size_estimate += value.size();
+        found_values.push_back(value);
+        break;
+      }
+      default:
+        NOTREACHED();
+    }
+    size_estimate += cursor_->cursor_->key().size_estimate();
+    size_estimate += cursor_->cursor_->primary_key().size_estimate();
+
+    if (size_estimate > max_size_estimate)
+      break;
+  }
+
+  if (!found_keys.size()) {
+    callbacks_->OnSuccess(static_cast<std::vector<char>*>(NULL));
+    return;
+  }
+
+  callbacks_->OnSuccessWithPrefetch(
+      found_keys, found_primary_keys, found_values);
+}
+
+void IndexedDBCursorImpl::PrefetchReset(int used_prefetches, int) {
+  IDB_TRACE("IndexedDBCursorImpl::prefetch_reset");
+  cursor_.swap(saved_cursor_);
+  saved_cursor_.reset();
+
+  if (closed_)
+    return;
+  if (cursor_) {
+    for (int i = 0; i < used_prefetches; ++i) {
+      bool ok = cursor_->ContinueFunction();
+      DCHECK(ok);
+    }
+  }
+}
+
+void IndexedDBCursorImpl::Close() {
+  IDB_TRACE("IndexedDBCursorImpl::close");
+  closed_ = true;
+  cursor_.reset();
+  saved_cursor_.reset();
+}
+
+}  // namespace content