| /* |
| * Copyright 2006 The Android Open Source Project |
| * |
| * Use of this source code is governed by a BSD-style license that can be |
| * found in the LICENSE file. |
| */ |
| |
| #ifndef SkDescriptor_DEFINED |
| #define SkDescriptor_DEFINED |
| |
| #include <memory> |
| #include <new> |
| |
| #include "include/private/base/SkMacros.h" |
| #include "include/private/base/SkNoncopyable.h" |
| #include "src/base/SkBuffer.h" |
| #include "src/core/SkFontPriv.h" |
| #include "src/core/SkScalerContext.h" |
| |
| class SkDescriptor : SkNoncopyable { |
| public: |
| static size_t ComputeOverhead(int entryCount) { |
| SkASSERT(entryCount >= 0); |
| return sizeof(SkDescriptor) + entryCount * sizeof(Entry); |
| } |
| |
| static std::unique_ptr<SkDescriptor> Alloc(size_t length); |
| |
| // |
| // Ensure the unsized delete is called. |
| void operator delete(void* p); |
| void* operator new(size_t); |
| void* operator new(size_t, void* p) { return p; } |
| |
| void flatten(SkWriteBuffer& buffer) const; |
| |
| uint32_t getLength() const { return fLength; } |
| void* addEntry(uint32_t tag, size_t length, const void* data = nullptr); |
| void computeChecksum(); |
| |
| // Assumes that getLength <= capacity of this SkDescriptor. |
| bool isValid() const; |
| |
| #ifdef SK_DEBUG |
| void assertChecksum() const { |
| SkASSERT(SkDescriptor::ComputeChecksum(this) == fChecksum); |
| } |
| #endif |
| |
| const void* findEntry(uint32_t tag, uint32_t* length) const; |
| |
| std::unique_ptr<SkDescriptor> copy() const; |
| |
| // This assumes that all memory added has a length that is a multiple of 4. This is checked |
| // by the assert in addEntry. |
| bool operator==(const SkDescriptor& other) const; |
| bool operator!=(const SkDescriptor& other) const { return !(*this == other); } |
| |
| uint32_t getChecksum() const { return fChecksum; } |
| |
| struct Entry { |
| uint32_t fTag; |
| uint32_t fLen; |
| }; |
| |
| uint32_t getCount() const { return fCount; } |
| |
| SkString dumpRec() const; |
| |
| private: |
| SkDescriptor() = default; |
| friend class SkDescriptorTestHelper; |
| friend class SkAutoDescriptor; |
| |
| static uint32_t ComputeChecksum(const SkDescriptor* desc); |
| |
| uint32_t fChecksum{0}; // must be first |
| uint32_t fLength{sizeof(SkDescriptor)}; // must be second |
| uint32_t fCount{0}; |
| }; |
| |
| class SkAutoDescriptor { |
| public: |
| SkAutoDescriptor(); |
| explicit SkAutoDescriptor(size_t size); |
| explicit SkAutoDescriptor(const SkDescriptor&); |
| SkAutoDescriptor(const SkAutoDescriptor&); |
| SkAutoDescriptor& operator=(const SkAutoDescriptor&); |
| SkAutoDescriptor(SkAutoDescriptor&&); |
| SkAutoDescriptor& operator=(SkAutoDescriptor&&); |
| ~SkAutoDescriptor(); |
| |
| // Returns no value if there is an error. |
| static std::optional<SkAutoDescriptor> MakeFromBuffer(SkReadBuffer& buffer); |
| |
| void reset(size_t size); |
| void reset(const SkDescriptor& desc); |
| SkDescriptor* getDesc() const { SkASSERT(fDesc); return fDesc; } |
| |
| private: |
| void free(); |
| static constexpr size_t kStorageSize |
| = sizeof(SkDescriptor) |
| + sizeof(SkDescriptor::Entry) + sizeof(SkScalerContextRec) // for rec |
| + sizeof(SkDescriptor::Entry) + sizeof(void*) // for typeface |
| + 32; // slop for occasional small extras |
| |
| SkDescriptor* fDesc{nullptr}; |
| alignas(uint32_t) char fStorage[kStorageSize]; |
| }; |
| |
| #endif //SkDescriptor_DEFINED |