extern "C" { #include #include #include #include #include } // Default deleter for pointer types. template struct DefaultDelete { enum { type_must_be_complete = sizeof(T) }; DefaultDelete() {} void operator()(T* p) const { delete p; } }; // Default deleter for array types. template struct DefaultDelete { enum { type_must_be_complete = sizeof(T) }; void operator()(T* p) const { delete[] p; } }; // A smart pointer that deletes the given pointer on destruction. // Equivalent to C++0x's std::unique_ptr (a combination of boost::scoped_ptr // and boost::scoped_array). // Named to be in keeping with Android style but also to avoid // collision with any other implementation, until we can switch over // to unique_ptr. // Use thus: // UniquePtr c(new C); template > class UniquePtr { template friend class UniquePtr; public: UniquePtr() : mPtr(nullptr) {} // Construct a new UniquePtr, taking ownership of the given raw pointer. explicit UniquePtr(T* ptr) : mPtr(ptr) { } // NOLINTNEXTLINE(google-explicit-constructor) UniquePtr(const decltype(nullptr)&) : mPtr(nullptr) {} UniquePtr(UniquePtr && other): mPtr(other.mPtr) { other.mPtr = nullptr; } template // NOLINTNEXTLINE(google-explicit-constructor) UniquePtr(UniquePtr&& other) : mPtr(other.mPtr) { other.mPtr = nullptr; } UniquePtr& operator=(UniquePtr && other) { if (&other != this) { reset(); mPtr = other.release(); } return *this; } ~UniquePtr() { reset(); } // Accessors. T& operator*() const { return *mPtr; } T* operator->() const { return mPtr; } T* get() const { return mPtr; } // NOLINTNEXTLINE(google-explicit-constructor) operator bool() const { return mPtr != nullptr; } // Returns the raw pointer and hands over ownership to the caller. // The pointer will not be deleted by UniquePtr. T* release() __attribute__((warn_unused_result)) { T* result = mPtr; mPtr = nullptr; return result; } // Takes ownership of the given raw pointer. // If this smart pointer previously owned a different raw pointer, that // raw pointer will be freed. void reset(T* ptr = nullptr) { if (ptr != mPtr) { D()(mPtr); mPtr = ptr; } } private: // The raw pointer. T* mPtr; // Comparing unique pointers is probably a mistake, since they're unique. template bool operator==(const UniquePtr& p) const; template bool operator!=(const UniquePtr& p) const; UniquePtr(const UniquePtr&) = delete; UniquePtr & operator=(const UniquePtr&) = delete; }; // Partial specialization for array types. Like std::unique_ptr, this removes // operator* and operator-> but adds operator[]. template class UniquePtr { public: UniquePtr() : mPtr(nullptr) {} explicit UniquePtr(T* ptr) : mPtr(ptr) { } // NOLINTNEXTLINE(google-explicit-constructor) UniquePtr(const decltype(nullptr)&) : mPtr(nullptr) {} UniquePtr(UniquePtr && other): mPtr(other.mPtr) { other.mPtr = nullptr; } UniquePtr& operator=(UniquePtr && other) { if (&other != this) { reset(); mPtr = other.release(); } return *this; } ~UniquePtr() { reset(); } T& operator[](size_t i) const { return mPtr[i]; } T* get() const { return mPtr; } T* release() __attribute__((warn_unused_result)) { T* result = mPtr; mPtr = nullptr; return result; } // NOLINTNEXTLINE(google-explicit-constructor) operator bool() const { return mPtr != nullptr; } void reset(T* ptr = nullptr) { if (ptr != mPtr) { D()(mPtr); mPtr = ptr; } } private: T* mPtr; UniquePtr(const UniquePtr&) = delete; UniquePtr & operator=(const UniquePtr&) = delete; }; #if UNIQUE_PTR_TESTS // Run these tests with: // g++ -g -DUNIQUE_PTR_TESTS -x c++ UniquePtr.h && ./a.out #include using namespace keymaster; static void assert(bool b) { if (!b) { fprintf(stderr, "FAIL\n"); abort(); } fprintf(stderr, "OK\n"); } static int cCount = 0; struct C { C() { ++cCount; } ~C() { --cCount; } }; static bool freed = false; struct Freer { void operator()(int* p) { assert(*p == 123); free(p); freed = true; } }; int main(int argc, char* argv[]) { // // UniquePtr tests... // // Can we free a single object? { UniquePtr c(new C); assert(cCount == 1); } assert(cCount == 0); // Does release work? C* rawC; { UniquePtr c(new C); assert(cCount == 1); rawC = c.release(); } assert(cCount == 1); delete rawC; // Does reset work? { UniquePtr c(new C); assert(cCount == 1); c.reset(new C); assert(cCount == 1); } assert(cCount == 0); // // UniquePtr tests... // // Can we free an array? { UniquePtr cs(new C[4]); assert(cCount == 4); } assert(cCount == 0); // Does release work? { UniquePtr c(new C[4]); assert(cCount == 4); rawC = c.release(); } assert(cCount == 4); delete[] rawC; // Does reset work? { UniquePtr c(new C[4]); assert(cCount == 4); c.reset(new C[2]); assert(cCount == 2); } assert(cCount == 0); // // Custom deleter tests... // assert(!freed); { UniquePtr i(reinterpret_cast(malloc(sizeof(int)))); *i = 123; } assert(freed); return 0; } #endif