forked from mirrors/gecko-dev
		
	 2da84b8ac4
			
		
	
	
		2da84b8ac4
		
	
	
	
	
		
			
			There are only 3 places where nsMemory.h is still needed (image/RasterImage.cpp, gfx/thebes/gfxFT2FontList.cpp, and nsMemory.cpp). Remove the rest. Differential Revision: https://phabricator.services.mozilla.com/D158213
		
			
				
	
	
		
			435 lines
		
	
	
	
		
			13 KiB
		
	
	
	
		
			C++
		
	
	
	
	
	
			
		
		
	
	
			435 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 "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() = default;
 | |
| };
 | |
| 
 | |
| 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__
 |