| /* |
| * Copyright 2018 Google Inc. |
| * |
| * Use of this source code is governed by a BSD-style license that can be |
| * found in the LICENSE file. |
| */ |
| |
| #ifndef GrCCSTLList_DEFINED |
| #define GrCCSTLList_DEFINED |
| |
| #include "include/private/SkNoncopyable.h" |
| #include "src/core/SkArenaAlloc.h" |
| #include <new> |
| |
| /** |
| * A singly-linked list whose head element is a local class member. This is required by |
| * GrCCDrawPathsOp because the owning opsTask is unknown at the time of creation, so we can't use |
| * its associated allocator to create the first element. |
| */ |
| template<typename T> class GrCCSTLList : SkNoncopyable { |
| public: |
| template <typename ...Args> |
| GrCCSTLList(Args&&... args) : fHead(std::forward<Args>(args)...) {} |
| |
| ~GrCCSTLList() { |
| T* draw = fHead.fNext; // fHead will be destructed automatically. |
| while (draw) { |
| T* next = draw->fNext; |
| draw->~T(); |
| draw = next; |
| } |
| } |
| |
| const T& head() const { return fHead; } |
| T& head() { return fHead; } |
| |
| void append(GrCCSTLList&& right, SkArenaAlloc* alloc) { |
| T* nextTail = (&right.fHead == right.fTail) ? nullptr : right.fTail; |
| T* newRightHead = |
| new (alloc->makeBytesAlignedTo(sizeof(T), alignof(T))) T(std::move(right.fHead)); |
| |
| // Finish the move of right.fHead. |
| right.fHead.fNext = nullptr; |
| right.fTail = &right.fHead; |
| |
| fTail->fNext = newRightHead; |
| fTail = !nextTail ? newRightHead : nextTail; |
| } |
| |
| template<typename U> struct Iter { |
| bool operator!=(const Iter& that) { return fCurr != that.fCurr; } |
| U& operator*() { return *fCurr; } |
| void operator++() { fCurr = fCurr->fNext; } |
| U* fCurr; |
| }; |
| Iter<const T> begin() const { return Iter<const T>{&fHead}; } |
| Iter<const T> end() const { return Iter<const T>{nullptr}; } |
| Iter<T> begin() { return Iter<T>{&fHead}; } |
| Iter<T> end() { return Iter<T>{nullptr}; } |
| |
| private: |
| T fHead; |
| T* fTail = &fHead; |
| }; |
| |
| #endif |