Mypal/storage/mozStoragePrivateHelpers.h

144 lines
4.4 KiB
C++

/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*-
* vim: sw=2 ts=2 et lcs=trail\:.,tab\:>~ :
* This Source Code Form is subject to the terms of the Mozilla Public
* License, v. 2.0. If a copy of the MPL was not distributed with this
* file, You can obtain one at http://mozilla.org/MPL/2.0/. */
#ifndef mozStoragePrivateHelpers_h
#define mozStoragePrivateHelpers_h
/**
* This file contains convenience methods for mozStorage.
*/
#include "sqlite3.h"
#include "nsIVariant.h"
#include "nsError.h"
#include "nsAutoPtr.h"
#include "js/TypeDecls.h"
#include "Variant.h"
class mozIStorageCompletionCallback;
class nsIRunnable;
namespace mozilla {
namespace storage {
////////////////////////////////////////////////////////////////////////////////
//// Macros
#define ENSURE_INDEX_VALUE(aIndex, aCount) \
NS_ENSURE_TRUE(aIndex < aCount, NS_ERROR_INVALID_ARG)
////////////////////////////////////////////////////////////////////////////////
//// Functions
/**
* Converts a SQLite return code to an nsresult return code.
*
* @param aSQLiteResultCode
* The SQLite return code to convert.
* @returns the corresponding nsresult code for aSQLiteResultCode.
*/
nsresult convertResultCode(int aSQLiteResultCode);
/**
* Checks the performance of a SQLite statement and logs a warning with
* NS_WARNING. Currently this only checks the number of sort operations done
* on a statement, and if more than zero have been done, the statement can be
* made faster with the careful use of an index.
*
* @param aStatement
* The sqlite3_stmt object to check.
*/
void checkAndLogStatementPerformance(sqlite3_stmt *aStatement);
/**
* Convert the provided JS::Value into a variant representation if possible.
*
* @param aCtx
* The JSContext the value is from.
* @param aValue
* The JavaScript value to convert. All primitive types are supported,
* but only Date objects are supported from the Date family. Date
* objects are coerced to PRTime (nanoseconds since epoch) values.
* @return the variant if conversion was successful, nullptr if conversion
* failed. The caller is responsible for addref'ing if non-null.
*/
nsIVariant *convertJSValToVariant(JSContext *aCtx, const JS::Value& aValue);
/**
* Convert a provided nsIVariant implementation to our own thread-safe
* refcounting implementation, if needed.
*
* @param aValue
* The original nsIVariant to be converted.
* @return a thread-safe refcounting nsIVariant implementation.
*/
Variant_base *convertVariantToStorageVariant(nsIVariant *aVariant);
/**
* Obtains an event that will notify a completion callback about completion.
*
* @param aCallback
* The callback to be notified.
* @return an nsIRunnable that can be dispatched to the calling thread.
*/
already_AddRefed<nsIRunnable> newCompletionEvent(
mozIStorageCompletionCallback *aCallback
);
/**
* Utility method to get a Blob as a string value. The string expects
* the interface exposed by nsAString/nsACString/etc.
*/
template<class T, class V>
nsresult
DoGetBlobAsString(T* aThis, uint32_t aIndex, V& aValue)
{
typedef typename V::char_type char_type;
uint32_t size;
char_type* blob;
nsresult rv =
aThis->GetBlob(aIndex, &size, reinterpret_cast<uint8_t**>(&blob));
NS_ENSURE_SUCCESS(rv, rv);
aValue.Assign(blob, size / sizeof(char_type));
delete[] blob;
return NS_OK;
}
/**
* Utility method to bind a string value as a Blob. The string expects
* the interface exposed by nsAString/nsACString/etc.
*/
template<class T, class V>
nsresult
DoBindStringAsBlobByName(T* aThis, const nsACString& aName, const V& aValue)
{
typedef typename V::char_type char_type;
return aThis->BindBlobByName(aName,
reinterpret_cast<const uint8_t*>(aValue.BeginReading()),
aValue.Length() * sizeof(char_type));
}
/**
* Utility method to bind a string value as a Blob. The string expects
* the interface exposed by nsAString/nsACString/etc.
*/
template<class T, class V>
nsresult
DoBindStringAsBlobByIndex(T* aThis, uint32_t aIndex, const V& aValue)
{
typedef typename V::char_type char_type;
return aThis->BindBlobByIndex(aIndex,
reinterpret_cast<const uint8_t*>(aValue.BeginReading()),
aValue.Length() * sizeof(char_type));
}
} // namespace storage
} // namespace mozilla
#endif // mozStoragePrivateHelpers_h