mirror of
https://github.com/mozilla/gecko-dev.git
synced 2024-11-25 05:41:12 +00:00
e226046cb8
# ignore-this-changeset Depends on D28954 Differential Revision: https://phabricator.services.mozilla.com/D28956 --HG-- extra : moz-landing-system : lando
437 lines
13 KiB
C++
437 lines
13 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 mozilla_storage_Variant_h__
|
|
#define mozilla_storage_Variant_h__
|
|
|
|
#include <utility>
|
|
|
|
#include "nsIVariant.h"
|
|
#include "nsMemory.h"
|
|
#include "nsString.h"
|
|
#include "nsTArray.h"
|
|
|
|
#define VARIANT_BASE_IID \
|
|
{ /* 78888042-0fa3-4f7a-8b19-7996f99bf1aa */ \
|
|
0x78888042, 0x0fa3, 0x4f7a, { \
|
|
0x8b, 0x19, 0x79, 0x96, 0xf9, 0x9b, 0xf1, 0xaa \
|
|
} \
|
|
}
|
|
|
|
/**
|
|
* This class is used by the storage module whenever an nsIVariant needs to be
|
|
* returned. We provide traits for the basic sqlite types to make use easier.
|
|
* The following types map to the indicated sqlite type:
|
|
* int64_t -> INTEGER (use IntegerVariant)
|
|
* double -> FLOAT (use FloatVariant)
|
|
* nsString -> TEXT (use TextVariant)
|
|
* nsCString -> TEXT (use UTF8TextVariant)
|
|
* uint8_t[] -> BLOB (use BlobVariant)
|
|
* nullptr -> NULL (use NullVariant)
|
|
*
|
|
* The kvstore component also reuses this class as a common implementation
|
|
* of a simple threadsafe variant for the storage of primitive values only.
|
|
* The BooleanVariant type has been introduced for kvstore use cases and should
|
|
* be enhanced to provide full boolean variant support for mozStorage.
|
|
*
|
|
* Bug 1494102 tracks that work.
|
|
*/
|
|
|
|
namespace mozilla {
|
|
namespace storage {
|
|
|
|
////////////////////////////////////////////////////////////////////////////////
|
|
//// Base Class
|
|
|
|
class Variant_base : public nsIVariant {
|
|
public:
|
|
NS_DECL_THREADSAFE_ISUPPORTS
|
|
NS_DECL_NSIVARIANT
|
|
NS_DECLARE_STATIC_IID_ACCESSOR(VARIANT_BASE_IID)
|
|
|
|
protected:
|
|
virtual ~Variant_base() {}
|
|
};
|
|
|
|
NS_DEFINE_STATIC_IID_ACCESSOR(Variant_base, VARIANT_BASE_IID)
|
|
|
|
////////////////////////////////////////////////////////////////////////////////
|
|
//// Traits
|
|
|
|
/**
|
|
* Generics
|
|
*/
|
|
|
|
template <typename DataType>
|
|
struct variant_traits {
|
|
static inline uint16_t type() { return nsIDataType::VTYPE_EMPTY; }
|
|
};
|
|
|
|
template <typename DataType, bool Adopting = false>
|
|
struct variant_storage_traits {
|
|
typedef DataType ConstructorType;
|
|
typedef DataType StorageType;
|
|
static inline void storage_conversion(const ConstructorType aData,
|
|
StorageType* _storage) {
|
|
*_storage = aData;
|
|
}
|
|
|
|
static inline void destroy(const StorageType& _storage) {}
|
|
};
|
|
|
|
#define NO_CONVERSION return NS_ERROR_CANNOT_CONVERT_DATA;
|
|
|
|
template <typename DataType, bool Adopting = false>
|
|
struct variant_boolean_traits {
|
|
typedef typename variant_storage_traits<DataType, Adopting>::StorageType
|
|
StorageType;
|
|
static inline nsresult asBool(const StorageType&, bool*) { NO_CONVERSION }
|
|
};
|
|
|
|
template <typename DataType, bool Adopting = false>
|
|
struct variant_integer_traits {
|
|
typedef typename variant_storage_traits<DataType, Adopting>::StorageType
|
|
StorageType;
|
|
static inline nsresult asInt32(const StorageType&, int32_t*) { NO_CONVERSION }
|
|
static inline nsresult asInt64(const StorageType&, int64_t*) { NO_CONVERSION }
|
|
};
|
|
|
|
template <typename DataType, bool Adopting = false>
|
|
struct variant_float_traits {
|
|
typedef typename variant_storage_traits<DataType, Adopting>::StorageType
|
|
StorageType;
|
|
static inline nsresult asDouble(const StorageType&, double*) { NO_CONVERSION }
|
|
};
|
|
|
|
template <typename DataType, bool Adopting = false>
|
|
struct variant_text_traits {
|
|
typedef typename variant_storage_traits<DataType, Adopting>::StorageType
|
|
StorageType;
|
|
static inline nsresult asUTF8String(const StorageType&, nsACString&) {
|
|
NO_CONVERSION
|
|
}
|
|
static inline nsresult asString(const StorageType&, nsAString&) {
|
|
NO_CONVERSION
|
|
}
|
|
};
|
|
|
|
template <typename DataType, bool Adopting = false>
|
|
struct variant_blob_traits {
|
|
typedef typename variant_storage_traits<DataType, Adopting>::StorageType
|
|
StorageType;
|
|
static inline nsresult asArray(const StorageType&, uint16_t*, uint32_t*,
|
|
void**) {
|
|
NO_CONVERSION
|
|
}
|
|
};
|
|
|
|
#undef NO_CONVERSION
|
|
|
|
/**
|
|
* BOOLEAN type
|
|
*/
|
|
|
|
template <>
|
|
struct variant_traits<bool> {
|
|
static inline uint16_t type() { return nsIDataType::VTYPE_BOOL; }
|
|
};
|
|
template <>
|
|
struct variant_boolean_traits<bool> {
|
|
static inline nsresult asBool(bool aValue, bool* _result) {
|
|
*_result = aValue;
|
|
return NS_OK;
|
|
}
|
|
|
|
// NB: It might be worth also providing conversions to int types.
|
|
|
|
// NB: It'd be nice to implement asBool conversions for 0 and 1, too.
|
|
// That would let us clean up some conversions in Places, such as:
|
|
// https://searchfox.org/mozilla-central/rev/0640ea80fbc8d48f8b197cd363e2535c95a15eb3/toolkit/components/places/SQLFunctions.cpp#564-565
|
|
// https://searchfox.org/mozilla-central/rev/0640ea80fbc8d48f8b197cd363e2535c95a15eb3/toolkit/components/places/SQLFunctions.cpp#1057
|
|
// https://searchfox.org/mozilla-central/rev/0640ea80fbc8d48f8b197cd363e2535c95a15eb3/toolkit/components/places/nsNavHistory.cpp#3189
|
|
};
|
|
|
|
/**
|
|
* INTEGER types
|
|
*/
|
|
|
|
template <>
|
|
struct variant_traits<int64_t> {
|
|
static inline uint16_t type() { return nsIDataType::VTYPE_INT64; }
|
|
};
|
|
template <>
|
|
struct variant_integer_traits<int64_t> {
|
|
static inline nsresult asInt32(int64_t aValue, int32_t* _result) {
|
|
if (aValue > INT32_MAX || aValue < INT32_MIN)
|
|
return NS_ERROR_CANNOT_CONVERT_DATA;
|
|
|
|
*_result = static_cast<int32_t>(aValue);
|
|
return NS_OK;
|
|
}
|
|
static inline nsresult asInt64(int64_t aValue, int64_t* _result) {
|
|
*_result = aValue;
|
|
return NS_OK;
|
|
}
|
|
};
|
|
// xpcvariant just calls get double for integers...
|
|
template <>
|
|
struct variant_float_traits<int64_t> {
|
|
static inline nsresult asDouble(int64_t aValue, double* _result) {
|
|
*_result = double(aValue);
|
|
return NS_OK;
|
|
}
|
|
};
|
|
|
|
/**
|
|
* FLOAT types
|
|
*/
|
|
|
|
template <>
|
|
struct variant_traits<double> {
|
|
static inline uint16_t type() { return nsIDataType::VTYPE_DOUBLE; }
|
|
};
|
|
template <>
|
|
struct variant_float_traits<double> {
|
|
static inline nsresult asDouble(double aValue, double* _result) {
|
|
*_result = aValue;
|
|
return NS_OK;
|
|
}
|
|
};
|
|
|
|
/**
|
|
* TEXT types
|
|
*/
|
|
|
|
template <>
|
|
struct variant_traits<nsString> {
|
|
static inline uint16_t type() { return nsIDataType::VTYPE_ASTRING; }
|
|
};
|
|
template <>
|
|
struct variant_storage_traits<nsString> {
|
|
typedef const nsAString& ConstructorType;
|
|
typedef nsString StorageType;
|
|
static inline void storage_conversion(ConstructorType aText,
|
|
StorageType* _outData) {
|
|
*_outData = aText;
|
|
}
|
|
static inline void destroy(const StorageType& _outData) {}
|
|
};
|
|
template <>
|
|
struct variant_text_traits<nsString> {
|
|
static inline nsresult asUTF8String(const nsString& aValue,
|
|
nsACString& _result) {
|
|
CopyUTF16toUTF8(aValue, _result);
|
|
return NS_OK;
|
|
}
|
|
static inline nsresult asString(const nsString& aValue, nsAString& _result) {
|
|
_result = aValue;
|
|
return NS_OK;
|
|
}
|
|
};
|
|
|
|
template <>
|
|
struct variant_traits<nsCString> {
|
|
static inline uint16_t type() { return nsIDataType::VTYPE_UTF8STRING; }
|
|
};
|
|
template <>
|
|
struct variant_storage_traits<nsCString> {
|
|
typedef const nsACString& ConstructorType;
|
|
typedef nsCString StorageType;
|
|
static inline void storage_conversion(ConstructorType aText,
|
|
StorageType* _outData) {
|
|
*_outData = aText;
|
|
}
|
|
static inline void destroy(const StorageType& aData) {}
|
|
};
|
|
template <>
|
|
struct variant_text_traits<nsCString> {
|
|
static inline nsresult asUTF8String(const nsCString& aValue,
|
|
nsACString& _result) {
|
|
_result = aValue;
|
|
return NS_OK;
|
|
}
|
|
static inline nsresult asString(const nsCString& aValue, nsAString& _result) {
|
|
CopyUTF8toUTF16(aValue, _result);
|
|
return NS_OK;
|
|
}
|
|
};
|
|
|
|
/**
|
|
* BLOB types
|
|
*/
|
|
|
|
template <>
|
|
struct variant_traits<uint8_t[]> {
|
|
static inline uint16_t type() { return nsIDataType::VTYPE_ARRAY; }
|
|
};
|
|
template <>
|
|
struct variant_storage_traits<uint8_t[], false> {
|
|
typedef std::pair<const void*, int> ConstructorType;
|
|
typedef FallibleTArray<uint8_t> StorageType;
|
|
static inline void storage_conversion(ConstructorType aBlob,
|
|
StorageType* _outData) {
|
|
_outData->Clear();
|
|
(void)_outData->AppendElements(static_cast<const uint8_t*>(aBlob.first),
|
|
aBlob.second, fallible);
|
|
}
|
|
static inline void destroy(const StorageType& _outData) {}
|
|
};
|
|
template <>
|
|
struct variant_storage_traits<uint8_t[], true> {
|
|
typedef std::pair<uint8_t*, int> ConstructorType;
|
|
typedef std::pair<uint8_t*, int> StorageType;
|
|
static inline void storage_conversion(ConstructorType aBlob,
|
|
StorageType* _outData) {
|
|
*_outData = aBlob;
|
|
}
|
|
static inline void destroy(StorageType& aData) {
|
|
if (aData.first) {
|
|
free(aData.first);
|
|
aData.first = nullptr;
|
|
}
|
|
}
|
|
};
|
|
template <>
|
|
struct variant_blob_traits<uint8_t[], false> {
|
|
static inline nsresult asArray(FallibleTArray<uint8_t>& aData,
|
|
uint16_t* _type, uint32_t* _size,
|
|
void** _result) {
|
|
// For empty blobs, we return nullptr.
|
|
if (aData.Length() == 0) {
|
|
*_result = nullptr;
|
|
*_type = nsIDataType::VTYPE_UINT8;
|
|
*_size = 0;
|
|
return NS_OK;
|
|
}
|
|
|
|
// Otherwise, we copy the array.
|
|
*_result = moz_xmemdup(aData.Elements(), aData.Length() * sizeof(uint8_t));
|
|
|
|
// Set type and size
|
|
*_type = nsIDataType::VTYPE_UINT8;
|
|
*_size = aData.Length();
|
|
return NS_OK;
|
|
}
|
|
};
|
|
|
|
template <>
|
|
struct variant_blob_traits<uint8_t[], true> {
|
|
static inline nsresult asArray(std::pair<uint8_t*, int>& aData,
|
|
uint16_t* _type, uint32_t* _size,
|
|
void** _result) {
|
|
// For empty blobs, we return nullptr.
|
|
if (aData.second == 0) {
|
|
*_result = nullptr;
|
|
*_type = nsIDataType::VTYPE_UINT8;
|
|
*_size = 0;
|
|
return NS_OK;
|
|
}
|
|
|
|
// Otherwise, transfer the data out.
|
|
*_result = aData.first;
|
|
aData.first = nullptr;
|
|
MOZ_ASSERT(*_result); // We asked for it twice, better not use adopting!
|
|
|
|
// Set type and size
|
|
*_type = nsIDataType::VTYPE_UINT8;
|
|
*_size = aData.second;
|
|
return NS_OK;
|
|
}
|
|
};
|
|
|
|
/**
|
|
* nullptr type
|
|
*/
|
|
|
|
class NullVariant : public Variant_base {
|
|
public:
|
|
uint16_t GetDataType() override { return nsIDataType::VTYPE_EMPTY; }
|
|
|
|
NS_IMETHOD GetAsAUTF8String(nsACString& _str) override {
|
|
// Return a void string.
|
|
_str.SetIsVoid(true);
|
|
return NS_OK;
|
|
}
|
|
|
|
NS_IMETHOD GetAsAString(nsAString& _str) override {
|
|
// Return a void string.
|
|
_str.SetIsVoid(true);
|
|
return NS_OK;
|
|
}
|
|
};
|
|
|
|
////////////////////////////////////////////////////////////////////////////////
|
|
//// Template Implementation
|
|
|
|
template <typename DataType, bool Adopting = false>
|
|
class Variant final : public Variant_base {
|
|
~Variant() { variant_storage_traits<DataType, Adopting>::destroy(mData); }
|
|
|
|
public:
|
|
explicit Variant(
|
|
const typename variant_storage_traits<DataType, Adopting>::ConstructorType
|
|
aData) {
|
|
variant_storage_traits<DataType, Adopting>::storage_conversion(aData,
|
|
&mData);
|
|
}
|
|
|
|
uint16_t GetDataType() override { return variant_traits<DataType>::type(); }
|
|
|
|
NS_IMETHOD GetAsBool(bool* _boolean) override {
|
|
return variant_boolean_traits<DataType, Adopting>::asBool(mData, _boolean);
|
|
}
|
|
|
|
NS_IMETHOD GetAsInt32(int32_t* _integer) override {
|
|
return variant_integer_traits<DataType, Adopting>::asInt32(mData, _integer);
|
|
}
|
|
|
|
NS_IMETHOD GetAsInt64(int64_t* _integer) override {
|
|
return variant_integer_traits<DataType, Adopting>::asInt64(mData, _integer);
|
|
}
|
|
|
|
NS_IMETHOD GetAsDouble(double* _double) override {
|
|
return variant_float_traits<DataType, Adopting>::asDouble(mData, _double);
|
|
}
|
|
|
|
NS_IMETHOD GetAsAUTF8String(nsACString& _str) override {
|
|
return variant_text_traits<DataType, Adopting>::asUTF8String(mData, _str);
|
|
}
|
|
|
|
NS_IMETHOD GetAsAString(nsAString& _str) override {
|
|
return variant_text_traits<DataType, Adopting>::asString(mData, _str);
|
|
}
|
|
|
|
NS_IMETHOD GetAsArray(uint16_t* _type, nsIID*, uint32_t* _size,
|
|
void** _data) override {
|
|
return variant_blob_traits<DataType, Adopting>::asArray(mData, _type, _size,
|
|
_data);
|
|
}
|
|
|
|
private:
|
|
typename variant_storage_traits<DataType, Adopting>::StorageType mData;
|
|
};
|
|
|
|
////////////////////////////////////////////////////////////////////////////////
|
|
//// Handy typedefs! Use these for the right mapping.
|
|
|
|
// Currently, BooleanVariant is only useful for kvstore.
|
|
// Bug 1494102 tracks implementing full boolean variant support for mozStorage.
|
|
typedef Variant<bool> BooleanVariant;
|
|
|
|
typedef Variant<int64_t> IntegerVariant;
|
|
typedef Variant<double> FloatVariant;
|
|
typedef Variant<nsString> TextVariant;
|
|
typedef Variant<nsCString> UTF8TextVariant;
|
|
typedef Variant<uint8_t[], false> BlobVariant;
|
|
typedef Variant<uint8_t[], true> AdoptedBlobVariant;
|
|
|
|
} // namespace storage
|
|
} // namespace mozilla
|
|
|
|
#include "Variant_inl.h"
|
|
|
|
#endif // mozilla_storage_Variant_h__
|