Revert of Use std::unique_ptr. (patchset #10 id:170001 of https://codereview.chromium.org/1780933003/ )

Reason for revert:
aww jeez, I dropped ps 8...

Original issue's description:
> Use std::unique_ptr.
>
> TBR=reed@google.com
>
> Committed: https://skia.googlesource.com/skia/+/20c1e3abfc681771f73eb19fde7284196e028940
>
> Committed: https://skia.googlesource.com/skia/+/3dd9ed37c24611af86f0fe374bd3698b63f09450
> GOLD_TRYBOT_URL= https://gold.skia.org/search2?unt=true&query=source_type%3Dgm&master=false&issue=1780933003
>
> Committed: https://skia.googlesource.com/skia/+/2691d76a06e1af6282f8b3a3140cc93361be10c4

TBR=bungeman@google.com,mtklein@chromium.org
# Skipping CQ checks because original CL landed less than 1 days ago.
NOPRESUBMIT=true
NOTREECHECKS=true
NOTRY=true

Review URL: https://codereview.chromium.org/1809693002

5 files changed, 424 insertions, 21 deletions

diff --git a/include/core/SkRefCnt.h b/include/core/SkRefCnt.h
index d18a63a49f..f159e3b1b7 100644
--- a/include/core/SkRefCnt.h
+++ b/include/core/SkRefCnt.h
@@ -9,10 +9,9 @@
 #define SkRefCnt_DEFINED
 
 #include "../private/SkAtomics.h"
-#include "../private/SkTLogic.h"
+#include "../private/SkUniquePtr.h"
 #include "SkTypes.h"
 #include <functional>
-#include <memory>
 #include <utility>
 
 #define SK_SUPPORT_TRANSITION_TO_SP_INTERFACES
@@ -190,16 +189,12 @@ template <typename T> struct SkTUnref {
 /**
  *  Utility class that simply unref's its argument in the destructor.
  */
-template <typename T> class SkAutoTUnref : public std::unique_ptr<T, SkTUnref<T>> {
+template <typename T> class SkAutoTUnref : public skstd::unique_ptr<T, SkTUnref<T>> {
 public:
-    explicit SkAutoTUnref(T* obj = nullptr) : std::unique_ptr<T, SkTUnref<T>>(obj) {}
+    explicit SkAutoTUnref(T* obj = nullptr) : skstd::unique_ptr<T, SkTUnref<T>>(obj) {}
 
     T* detach() { return this->release(); }
     operator T*() const { return this->get(); }
-
-    // Android's std::unique_ptr's operator bool() is sometimes not explicit...
-    // so override it with our own explcitly explicit version.
-    explicit operator bool() const { return this->get() != nullptr; }
 };
 // Can't use the #define trick below to guard a bare SkAutoTUnref(...) because it's templated. :(
 
diff --git a/include/gpu/gl/SkGLContext.h b/include/gpu/gl/SkGLContext.h
index fe41a606ef..ddf5dc080a 100644
--- a/include/gpu/gl/SkGLContext.h
+++ b/include/gpu/gl/SkGLContext.h
@@ -25,7 +25,7 @@ public:
 
     const GrGLInterface* gl() const { return fGL.get(); }
 
-    bool fenceSyncSupport() const { return fFenceSync != nullptr; }
+    bool fenceSyncSupport() const { return SkToBool(fFenceSync); }
 
     bool getMaxGpuFrameLag(int* maxFrameLag) const {
         if (!fFenceSync) {
diff --git a/include/private/SkOncePtr.h b/include/private/SkOncePtr.h
index 3c1ab634ee..261f9a7ef4 100644
--- a/include/private/SkOncePtr.h
+++ b/include/private/SkOncePtr.h
@@ -9,7 +9,7 @@
 #define SkOncePtr_DEFINED
 
 #include "../private/SkAtomics.h"
-#include <memory>
+#include "SkUniquePtr.h"
 
 template <typename T> class SkBaseOncePtr;
 
@@ -17,7 +17,7 @@ template <typename T> class SkBaseOncePtr;
 #define SK_DECLARE_STATIC_ONCE_PTR(type, name) namespace {} static SkBaseOncePtr<type> name;
 
 // Use this for a local or member pointer that's initialized exactly once when you call get().
-template <typename T, typename Delete = std::default_delete<T>>
+template <typename T, typename Delete = skstd::default_delete<T>>
 class SkOncePtr : SkNoncopyable {
 public:
     SkOncePtr() { sk_bzero(this, sizeof(*this)); }
@@ -42,7 +42,7 @@ private:
 
 // If you ask for SkOncePtr<T[]>, we'll clean up with delete[] by default.
 template <typename T>
-class SkOncePtr<T[]> : public SkOncePtr<T, std::default_delete<T[]>> {};
+class SkOncePtr<T[]> : public SkOncePtr<T, skstd::default_delete<T[]>> {};
 
 /* TODO(mtklein): in next CL
 typedef SkBaseOncePtr<void> SkOnceFlag;
diff --git a/include/private/SkTemplates.h b/include/private/SkTemplates.h
index e74f512623..e36910e814 100644
--- a/include/private/SkTemplates.h
+++ b/include/private/SkTemplates.h
@@ -13,8 +13,8 @@
 #include "SkMath.h"
 #include "SkTLogic.h"
 #include "SkTypes.h"
+#include "SkUniquePtr.h"
 #include <limits.h>
-#include <memory>
 #include <new>
 
 /** \file SkTemplates.h
@@ -58,9 +58,9 @@ template <typename R, typename T, R (*P)(T*)> struct SkFunctionWrapper {
     function.
 */
 template <typename T, void (*P)(T*)> class SkAutoTCallVProc
-    : public std::unique_ptr<T, SkFunctionWrapper<void, T, P>> {
+    : public skstd::unique_ptr<T, SkFunctionWrapper<void, T, P>> {
 public:
-    SkAutoTCallVProc(T* obj): std::unique_ptr<T, SkFunctionWrapper<void, T, P>>(obj) {}
+    SkAutoTCallVProc(T* obj): skstd::unique_ptr<T, SkFunctionWrapper<void, T, P>>(obj) {}
 
     operator T*() const { return this->get(); }
     T* detach() { return this->release(); }
@@ -75,9 +75,9 @@ reference is null when the destructor is called, we do not call the
 function.
 */
 template <typename T, int (*P)(T*)> class SkAutoTCallIProc
-    : public std::unique_ptr<T, SkFunctionWrapper<int, T, P>> {
+    : public skstd::unique_ptr<T, SkFunctionWrapper<int, T, P>> {
 public:
-    SkAutoTCallIProc(T* obj): std::unique_ptr<T, SkFunctionWrapper<int, T, P>>(obj) {}
+    SkAutoTCallIProc(T* obj): skstd::unique_ptr<T, SkFunctionWrapper<int, T, P>>(obj) {}
 
     operator T*() const { return this->get(); }
     T* detach() { return this->release(); }
@@ -93,18 +93,18 @@ public:
 
   The size of a SkAutoTDelete is small: sizeof(SkAutoTDelete<T>) == sizeof(T*)
 */
-template <typename T> class SkAutoTDelete : public std::unique_ptr<T> {
+template <typename T> class SkAutoTDelete : public skstd::unique_ptr<T> {
 public:
-    SkAutoTDelete(T* obj = NULL) : std::unique_ptr<T>(obj) {}
+    SkAutoTDelete(T* obj = NULL) : skstd::unique_ptr<T>(obj) {}
 
     operator T*() const { return this->get(); }
     void free() { this->reset(nullptr); }
     T* detach() { return this->release(); }
 };
 
-template <typename T> class SkAutoTDeleteArray : public std::unique_ptr<T[]> {
+template <typename T> class SkAutoTDeleteArray : public skstd::unique_ptr<T[]> {
 public:
-    SkAutoTDeleteArray(T array[]) : std::unique_ptr<T[]>(array) {}
+    SkAutoTDeleteArray(T array[]) : skstd::unique_ptr<T[]>(array) {}
 
     void free() { this->reset(nullptr); }
     T* detach() { return this->release(); }
diff --git a/include/private/SkUniquePtr.h b/include/private/SkUniquePtr.h
new file mode 100644
index 0000000000..b1097d51eb
--- /dev/null
+++ b/include/private/SkUniquePtr.h
@@ -0,0 +1,408 @@
+/*
+ * Copyright 2015 Google Inc.
+ *
+ * Use of this source code is governed by a BSD-style license that can be
+ * found in the LICENSE file.
+ */
+
+#ifndef SkUniquePtr_DEFINED
+#define SkUniquePtr_DEFINED
+
+#include "SkTLogic.h"
+#include <cstddef>
+#include <utility>
+
+namespace skstd {
+
+template <typename T> struct default_delete {
+    /*constexpr*/ default_delete() /*noexcept*/ = default;
+
+    template <typename U, typename = enable_if_t<is_convertible<U*, T*>::value>>
+    default_delete(const default_delete<U>&) /*noexcept*/ {}
+
+    void operator()(T* obj) const {
+        static_assert(sizeof(T) > 0, "Deleting pointer to incomplete type!");
+        delete obj;
+    }
+};
+template <typename T> struct default_delete<T[]> {
+    /*constexpr*/ default_delete() /*noexcept*/ = default;
+
+    void operator()(T* obj) const {
+        static_assert(sizeof(T) > 0, "Deleting pointer to incomplete type!");
+        delete [] obj;
+    }
+};
+
+template <typename T, typename D = default_delete<T>> class unique_ptr {
+    // remove_reference_t<D>::pointer if that type exists, otherwise T*.
+    struct pointer_type_detector {
+        template <typename U> static typename U::pointer detector(typename U::pointer*);
+        template <typename U> static T* detector(...);
+        using type = decltype(detector<remove_reference_t<D>>(0));
+    };
+
+public:
+    using pointer = typename pointer_type_detector::type;
+    using element_type = T;
+    using deleter_type = D;
+
+private:
+    template <typename B, bool>
+    struct compressed_base : private B {
+        /*constexpr*/ compressed_base() : B() {}
+        /*constexpr*/ compressed_base(const B& b) : B(b) {}
+        /*constexpr*/ compressed_base(B&& b) : B(std::move(b)) {}
+        /*constexpr*/ B& get() /*noexcept*/ { return *this; }
+        /*constexpr*/ B const& get() const /*noexcept*/ { return *this; }
+        void swap(compressed_base&) /*noexcept*/ { }
+    };
+
+    template <typename B> struct compressed_base<B, false> {
+        B fb;
+        /*constexpr*/ compressed_base() : B() {}
+        /*constexpr*/ compressed_base(const B& b) : fb(b) {}
+        /*constexpr*/ compressed_base(B&& b) : fb(std::move(b)) {}
+        /*constexpr*/ B& get() /*noexcept*/ { return fb; }
+        /*constexpr*/ B const& get() const /*noexcept*/ { return fb; }
+        void swap(compressed_base& that) /*noexcept*/ { SkTSwap(fb, that.fB); }
+    };
+
+    // C++14 adds '&& !std::is_final<deleter_type>::value' to the bool condition.
+    // compressed_base_t exists and has this form to work around a bug in vs2013sp2-3
+    using compressed_base_t = compressed_base<deleter_type, std::is_empty<deleter_type>::value>;
+
+    struct compressed_data : private compressed_base_t {
+        pointer fPtr;
+        /*constexpr*/ compressed_data() : compressed_base_t(), fPtr() {}
+        /*constexpr*/ compressed_data(const pointer& ptr, const deleter_type& d)
+            : compressed_base_t(d), fPtr(ptr) {}
+        template <typename U1, typename U2, typename = enable_if_t<
+            is_convertible<U1, pointer>::value && is_convertible<U2, deleter_type>::value
+        >> /*constexpr*/ compressed_data(U1&& ptr, U2&& d)
+            : compressed_base_t(std::forward<U2>(d)), fPtr(std::forward<U1>(ptr)) {}
+        /*constexpr*/ pointer& getPointer() /*noexcept*/ { return fPtr; }
+        /*constexpr*/ pointer const& getPointer() const /*noexcept*/ { return fPtr; }
+        /*constexpr*/ deleter_type& getDeleter() /*noexcept*/ {
+            return compressed_base_t::get();
+        }
+        /*constexpr*/ deleter_type const& getDeleter() const /*noexcept*/ {
+            return compressed_base_t::get();
+        }
+        void swap(compressed_data& that) /*noexcept*/ {
+            compressed_base_t::swap(static_cast<compressed_base_t>(that));
+            SkTSwap(fPtr, that.fPtr);
+        }
+    };
+    compressed_data data;
+
+public:
+    /*constexpr*/ unique_ptr() /*noexcept*/ : data() {
+        static_assert(!std::is_pointer<deleter_type>::value, "Deleter nullptr function pointer!");
+    }
+
+    /*constexpr*/ unique_ptr(std::nullptr_t) /*noexcept*/ : unique_ptr() { }
+
+    explicit unique_ptr(pointer ptr) /*noexcept*/ : data(ptr, deleter_type()) {
+        static_assert(!std::is_pointer<deleter_type>::value, "Deleter nullptr function pointer!");
+    }
+
+    unique_ptr(pointer ptr,
+               conditional_t<std::is_reference<deleter_type>::value,
+                             deleter_type, const deleter_type&> d)
+    /*noexcept*/ : data(ptr, d)
+    {}
+
+    unique_ptr(pointer ptr, remove_reference_t<deleter_type>&& d) /*noexcept*/
+        : data(std::move(ptr), std::move(d))
+    {
+        static_assert(!std::is_reference<deleter_type>::value,
+            "Binding an rvalue reference deleter as an lvalue reference deleter is not allowed.");
+    }
+
+
+    unique_ptr(unique_ptr&& that) /*noexcept*/
+        : data(that.release(), std::forward<deleter_type>(that.get_deleter()))
+    {}
+
+    template <typename U, typename ThatD, typename = enable_if_t<
+        is_convertible<typename unique_ptr<U, ThatD>::pointer, pointer>::value &&
+        !std::is_array<U>::value &&
+        conditional_t<std::is_reference<D>::value,
+                      std::is_same<ThatD, D>,
+                      is_convertible<ThatD, D>>::value>>
+    unique_ptr(unique_ptr<U, ThatD>&& that) /*noexcept*/
+        : data(that.release(), std::forward<ThatD>(that.get_deleter()))
+    {}
+
+    ~unique_ptr() /*noexcept*/ {
+        pointer& ptr = data.getPointer();
+        if (ptr != nullptr) {
+            get_deleter()(ptr);
+        }
+        ptr = pointer();
+    }
+
+    unique_ptr& operator=(unique_ptr&& that) /*noexcept*/ {
+        reset(that.release());
+        get_deleter() = std::forward<deleter_type>(that.get_deleter());
+        return *this;
+    }
+
+    template <typename U, typename ThatD> enable_if_t<
+        is_convertible<typename unique_ptr<U, ThatD>::pointer, pointer>::value &&
+        !std::is_array<U>::value,
+    unique_ptr&> operator=(unique_ptr<U, ThatD>&& that) /*noexcept*/ {
+        reset(that.release());
+        get_deleter() = std::forward<ThatD>(that.get_deleter());
+        return *this;
+    }
+
+    unique_ptr& operator=(std::nullptr_t) /*noexcept*/ {
+        reset();
+        return *this;
+    }
+
+    add_lvalue_reference_t<element_type> operator*() const {
+        SkASSERT(get() != pointer());
+        return *get();
+    }
+
+    pointer operator->() const /*noexcept*/ {
+        SkASSERT(get() != pointer());
+        return get();
+    }
+
+    pointer get() const /*noexcept*/ {
+        return data.getPointer();
+    }
+
+    deleter_type& get_deleter() /*noexcept*/ {
+        return data.getDeleter();
+    }
+
+    const deleter_type& get_deleter() const /*noexcept*/ {
+        return data.getDeleter();
+    }
+
+    //explicit operator bool() const noexcept {
+    bool is_attached() const /*noexcept*/ {
+        return get() == pointer() ? false : true;
+    }
+
+    pointer release() /*noexcept*/ {
+        pointer ptr = get();
+        data.getPointer() = pointer();
+        return ptr;
+    }
+
+    void reset(pointer ptr = pointer()) /*noexcept*/ {
+        SkTSwap(data.getPointer(), ptr);
+        if (ptr != pointer()) {
+            get_deleter()(ptr);
+        }
+    }
+
+    void swap(unique_ptr& that) /*noexcept*/ {
+        SkTSwap(data, that.data);
+    }
+
+    unique_ptr(const unique_ptr&) = delete;
+    unique_ptr& operator=(const unique_ptr&) = delete;
+};
+
+template <typename T, typename D> class unique_ptr<T[], D> {
+    // remove_reference_t<D>::pointer if that type exists, otherwise T*.
+    struct pointer_type_detector {
+        template <typename U> static typename U::pointer detector(typename U::pointer*);
+        template <typename U> static T* detector(...);
+        using type = decltype(detector<remove_reference_t<D>>(0));
+    };
+
+public:
+    using pointer = typename pointer_type_detector::type;
+    using element_type = T;
+    using deleter_type = D;
+
+private:
+    template <typename B, bool> struct compressed_base : private B {
+        /*constexpr*/ compressed_base() : B() {}
+        /*constexpr*/ compressed_base(const B& b) : B(b) {}
+        /*constexpr*/ compressed_base(B&& b) : B(std::move(b)) {}
+        /*constexpr*/ B& get() /*noexcept*/ { return *this; }
+        /*constexpr*/ B const& get() const /*noexcept*/ { return *this; }
+        void swap(compressed_base&) /*noexcept*/ { }
+    };
+
+    template <typename B> struct compressed_base<B, false> {
+        B fb;
+        /*constexpr*/ compressed_base() : B() {}
+        /*constexpr*/ compressed_base(const B& b) : fb(b) {}
+        /*constexpr*/ compressed_base(B&& b) : fb(std::move(b)) {}
+        /*constexpr*/ B& get() /*noexcept*/ { return fb; }
+        /*constexpr*/ B const& get() const /*noexcept*/ { return fb; }
+        void swap(compressed_base& that) /*noexcept*/ { SkTSwap(fb, that.fB); }
+    };
+
+    // C++14 adds '&& !std::is_final<deleter_type>::value' to the bool condition.
+    // compressed_base_t exists and has this form to work around a bug in vs2013sp2-3
+    using compressed_base_t = compressed_base<deleter_type, std::is_empty<deleter_type>::value>;
+
+    struct compressed_data : private compressed_base_t {
+        pointer fPtr;
+        /*constexpr*/ compressed_data() : compressed_base_t(), fPtr() {}
+        /*constexpr*/ compressed_data(const pointer& ptr, const deleter_type& d)
+            : compressed_base_t(d), fPtr(ptr) {}
+        template <typename U1, typename U2, typename = enable_if_t<
+            is_convertible<U1, pointer>::value && is_convertible<U2, deleter_type>::value
+        >> /*constexpr*/ compressed_data(U1&& ptr, U2&& d)
+            : compressed_base_t(std::forward<U2>(d)), fPtr(std::forward<U1>(ptr)) {}
+        /*constexpr*/ pointer& getPointer() /*noexcept*/ { return fPtr; }
+        /*constexpr*/ pointer const& getPointer() const /*noexcept*/ { return fPtr; }
+        /*constexpr*/ deleter_type& getDeleter() /*noexcept*/ {
+            return compressed_base_t::get();
+        }
+        /*constexpr*/ deleter_type const& getDeleter() const /*noexcept*/ {
+            return compressed_base_t::get();
+        }
+        void swap(compressed_data& that) /*noexcept*/ {
+            compressed_base_t::swap(static_cast<compressed_base_t>(that));
+            SkTSwap(fPtr, that.fPtr);
+        }
+    };
+    compressed_data data;
+
+public:
+    /*constexpr*/ unique_ptr() /*noexcept*/ : data() {
+        static_assert(!std::is_pointer<deleter_type>::value, "Deleter nullptr function pointer!");
+    }
+
+    /*constexpr*/ unique_ptr(std::nullptr_t) /*noexcept*/ : unique_ptr() { }
+
+    explicit unique_ptr(pointer ptr) /*noexcept*/ : data(ptr, deleter_type()) {
+        static_assert(!std::is_pointer<deleter_type>::value, "Deleter nullptr function pointer!");
+    }
+
+    unique_ptr(pointer ptr,
+               conditional_t<std::is_reference<deleter_type>::value,
+                             deleter_type, const deleter_type&> d)
+    /*noexcept*/ : data(ptr, d)
+    {}
+
+    unique_ptr(pointer ptr, remove_reference_t<deleter_type>&& d) /*noexcept*/
+        : data(std::move(ptr), std::move(d))
+    {
+        static_assert(!std::is_reference<deleter_type>::value,
+            "Binding an rvalue reference deleter as an lvalue reference deleter is not allowed.");
+    }
+
+    unique_ptr(unique_ptr&& that) /*noexcept*/
+        : data(that.release(), std::forward<deleter_type>(that.get_deleter()))
+    {}
+
+    ~unique_ptr() {
+        pointer& ptr = data.getPointer();
+        if (ptr != nullptr) {
+          get_deleter()(ptr);
+        }
+        ptr = pointer();
+    }
+
+    unique_ptr& operator=(unique_ptr&& that) /*noexcept*/ {
+        reset(that.release());
+        get_deleter() = std::forward<deleter_type>(that.get_deleter());
+        return *this;
+    }
+
+    unique_ptr& operator=(std::nullptr_t) /*noexcept*/ {
+        reset();
+        return *this;
+    }
+
+    add_lvalue_reference_t<element_type> operator[](size_t i) const {
+        SkASSERT(get() != pointer());
+        return get()[i];
+    }
+
+    pointer get() const /*noexcept*/ {
+        return data.getPointer();
+    }
+
+    deleter_type& get_deleter() /*noexcept*/ {
+        return data.getDeleter();
+    }
+
+    const deleter_type& get_deleter() const /*noexcept*/ {
+        return data.getDeleter();
+    }
+
+    //explicit operator bool() const noexcept {
+    bool is_attached() const /*noexcept*/ {
+        return get() == pointer() ? false : true;
+    }
+
+    pointer release() /*noexcept*/ {
+        pointer ptr = get();
+        data.getPointer() = pointer();
+        return ptr;
+    }
+
+    void reset(pointer ptr = pointer()) /*noexcept*/ {
+        SkTSwap(data.getPointer(), ptr);
+        if (ptr != pointer()) {
+            get_deleter()(ptr);
+        }
+    }
+
+    template <typename U> void reset(U*) = delete;
+
+    void swap(unique_ptr& that) /*noexcept*/ {
+        data.swap(that.data);
+    }
+
+    unique_ptr(const unique_ptr&) = delete;
+    unique_ptr& operator=(const unique_ptr&) = delete;
+};
+
+template <typename T, typename D>
+inline void swap(unique_ptr<T, D>& a, unique_ptr<T, D>& b) /*noexcept*/ {
+    a.swap(b);
+}
+
+template <typename T, typename D, typename U, typename ThatD>
+inline bool operator==(const unique_ptr<T, D>& a, const unique_ptr<U, ThatD>& b) {
+    return a.get() == b.get();
+}
+
+template <typename T, typename D>
+inline bool operator==(const unique_ptr<T, D>& a, std::nullptr_t) /*noexcept*/ {
+    //return !a;
+    return !a.is_attached();
+}
+
+template <typename T, typename D>
+inline bool operator==(std::nullptr_t, const unique_ptr<T, D>& b) /*noexcept*/ {
+    //return !b;
+    return !b.is_attached();
+}
+
+template <typename T, typename D, typename U, typename ThatD>
+inline bool operator!=(const unique_ptr<T, D>& a, const unique_ptr<U, ThatD>& b) {
+    return a.get() != b.get();
+}
+
+template <typename T, typename D>
+inline bool operator!=(const unique_ptr<T, D>& a, std::nullptr_t) /*noexcept*/ {
+    //return (bool)a;
+    return a.is_attached();
+}
+
+template <typename T, typename D>
+inline bool operator!=(std::nullptr_t, const unique_ptr<T, D>& b) /*noexcept*/ {
+    //return (bool)b;
+    return b.is_attached();
+}
+
+}  // namespace skstd
+
+#endif