gecko-dev/dom/indexedDB/Key.h

301 строка
7.1 KiB
C++

/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
/* vim: set ts=2 et sw=2 tw=80: */
/* 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 mozilla_dom_indexeddb_key_h__
#define mozilla_dom_indexeddb_key_h__
#include "mozilla/dom/indexedDB/IndexedDatabase.h"
#include "mozIStorageStatement.h"
namespace IPC {
template <typename T> struct ParamTraits;
} // namespace IPC
BEGIN_INDEXEDDB_NAMESPACE
class Key
{
friend struct IPC::ParamTraits<Key>;
public:
Key()
{
Unset();
}
Key& operator=(const nsAString& aString)
{
SetFromString(aString);
return *this;
}
Key& operator=(PRInt64 aInt)
{
SetFromInteger(aInt);
return *this;
}
bool operator==(const Key& aOther) const
{
NS_ASSERTION(!mBuffer.IsVoid() && !aOther.mBuffer.IsVoid(),
"Don't compare unset keys!");
return mBuffer.Equals(aOther.mBuffer);
}
bool operator!=(const Key& aOther) const
{
NS_ASSERTION(!mBuffer.IsVoid() && !aOther.mBuffer.IsVoid(),
"Don't compare unset keys!");
return !mBuffer.Equals(aOther.mBuffer);
}
bool operator<(const Key& aOther) const
{
NS_ASSERTION(!mBuffer.IsVoid() && !aOther.mBuffer.IsVoid(),
"Don't compare unset keys!");
return Compare(mBuffer, aOther.mBuffer) < 0;
}
bool operator>(const Key& aOther) const
{
NS_ASSERTION(!mBuffer.IsVoid() && !aOther.mBuffer.IsVoid(),
"Don't compare unset keys!");
return Compare(mBuffer, aOther.mBuffer) > 0;
}
bool operator<=(const Key& aOther) const
{
NS_ASSERTION(!mBuffer.IsVoid() && !aOther.mBuffer.IsVoid(),
"Don't compare unset keys!");
return Compare(mBuffer, aOther.mBuffer) <= 0;
}
bool operator>=(const Key& aOther) const
{
NS_ASSERTION(!mBuffer.IsVoid() && !aOther.mBuffer.IsVoid(),
"Don't compare unset keys!");
return Compare(mBuffer, aOther.mBuffer) >= 0;
}
void
Unset()
{
mBuffer.SetIsVoid(true);
}
bool IsUnset() const
{
return mBuffer.IsVoid();
}
bool IsFloat() const
{
return !mBuffer.IsVoid() && mBuffer.First() == eFloat;
}
double ToFloat() const
{
NS_ASSERTION(IsFloat(), "Why'd you call this?");
const unsigned char* pos = BufferStart();
double res = DecodeNumber(pos, BufferEnd());
NS_ASSERTION(pos >= BufferEnd(), "Should consume whole buffer");
return res;
}
void SetFromString(const nsAString& aString)
{
mBuffer.Truncate();
EncodeString(aString, 0);
TrimBuffer();
}
void SetFromInteger(PRInt64 aInt)
{
mBuffer.Truncate();
EncodeNumber(double(aInt), eFloat);
TrimBuffer();
}
nsresult SetFromJSVal(JSContext* aCx,
const jsval aVal)
{
mBuffer.Truncate();
if (JSVAL_IS_NULL(aVal) || JSVAL_IS_VOID(aVal)) {
Unset();
return NS_OK;
}
nsresult rv = EncodeJSVal(aCx, aVal, 0);
if (NS_FAILED(rv)) {
Unset();
return rv;
}
TrimBuffer();
return NS_OK;
}
nsresult ToJSVal(JSContext* aCx,
jsval* aVal) const
{
if (IsUnset()) {
*aVal = JSVAL_VOID;
return NS_OK;
}
const unsigned char* pos = BufferStart();
nsresult rv = DecodeJSVal(pos, BufferEnd(), aCx, 0, aVal);
NS_ENSURE_SUCCESS(rv, rv);
NS_ASSERTION(pos >= BufferEnd(),
"Didn't consume whole buffer");
return NS_OK;
}
nsresult AppendItem(JSContext* aCx,
bool aFirstOfArray,
const jsval aVal)
{
nsresult rv = EncodeJSVal(aCx, aVal, aFirstOfArray ? eMaxType : 0);
if (NS_FAILED(rv)) {
Unset();
return rv;
}
return NS_OK;
}
void FinishArray()
{
TrimBuffer();
}
const nsCString& GetBuffer() const
{
return mBuffer;
}
nsresult BindToStatement(mozIStorageStatement* aStatement,
const nsACString& aParamName) const
{
nsresult rv = aStatement->BindBlobByName(aParamName,
reinterpret_cast<const PRUint8*>(mBuffer.get()), mBuffer.Length());
return NS_SUCCEEDED(rv) ? NS_OK : NS_ERROR_DOM_INDEXEDDB_UNKNOWN_ERR;
}
nsresult SetFromStatement(mozIStorageStatement* aStatement,
PRUint32 aIndex)
{
PRUint8* data;
PRUint32 dataLength = 0;
nsresult rv = aStatement->GetBlob(aIndex, &dataLength, &data);
NS_ENSURE_SUCCESS(rv, NS_ERROR_DOM_INDEXEDDB_UNKNOWN_ERR);
mBuffer.Adopt(
reinterpret_cast<char*>(const_cast<PRUint8*>(data)), dataLength);
return NS_OK;
}
static
PRInt16 CompareKeys(Key& aFirst, Key& aSecond)
{
PRInt32 result = Compare(aFirst.mBuffer, aSecond.mBuffer);
if (result < 0) {
return -1;
}
if (result > 0) {
return 1;
}
return 0;
}
private:
const unsigned char* BufferStart() const
{
return reinterpret_cast<const unsigned char*>(mBuffer.BeginReading());
}
const unsigned char* BufferEnd() const
{
return reinterpret_cast<const unsigned char*>(mBuffer.EndReading());
}
enum {
eTerminator = 0,
eFloat = 1,
eDate = 2,
eString = 3,
eArray = 4,
eMaxType = eArray
};
// Encoding helper. Trims trailing zeros off of mBuffer as a post-processing
// step.
void TrimBuffer()
{
const char* end = mBuffer.EndReading() - 1;
while (!*end) {
--end;
}
mBuffer.Truncate(end + 1 - mBuffer.BeginReading());
}
// Encoding functions. These append the encoded value to the end of mBuffer
inline nsresult EncodeJSVal(JSContext* aCx, const jsval aVal,
PRUint8 aTypeOffset)
{
return EncodeJSValInternal(aCx, aVal, aTypeOffset, 0);
}
void EncodeString(const nsAString& aString, PRUint8 aTypeOffset);
void EncodeNumber(double aFloat, PRUint8 aType);
// Decoding functions. aPos points into mBuffer and is adjusted to point
// past the consumed value.
static inline nsresult DecodeJSVal(const unsigned char*& aPos,
const unsigned char* aEnd, JSContext* aCx,
PRUint8 aTypeOffset, jsval* aVal)
{
return DecodeJSValInternal(aPos, aEnd, aCx, aTypeOffset, aVal, 0);
}
static void DecodeString(const unsigned char*& aPos,
const unsigned char* aEnd,
nsString& aString);
static double DecodeNumber(const unsigned char*& aPos,
const unsigned char* aEnd);
nsCString mBuffer;
private:
nsresult EncodeJSValInternal(JSContext* aCx, const jsval aVal,
PRUint8 aTypeOffset, PRUint16 aRecursionDepth);
static nsresult DecodeJSValInternal(const unsigned char*& aPos,
const unsigned char* aEnd,
JSContext* aCx, PRUint8 aTypeOffset,
jsval* aVal, PRUint16 aRecursionDepth);
};
END_INDEXEDDB_NAMESPACE
#endif /* mozilla_dom_indexeddb_key_h__ */