fix null deref on moved Cow

Makefile

@@ -5,7 +5,7 @@ PROJECT=cow
 AUTHOR=Avril (Flanchan) <flanchan@cumallover.me>
 
 VERSION_MAJOR=0
-VERSION_MINOR=1.4
+VERSION_MINOR=1.5
 VERSION=$(VERSION_MAJOR).$(VERSION_MINOR)
 
 ifeq ($(PREFIX),)

include/cow.hpp

@@ -16,8 +16,14 @@ struct Cow : public _cow_util::Span<unsigned char> {
 
 	virtual Fake clone() const;
 
-	inline void* area() override { return cow_ptr(get_raw()); }
-	inline const void* area() const override { return cow_ptr_of(const void, get_raw()); }
+	inline void* area() override { 
+		auto raw = get_raw();
+		return raw ? cow_ptr(raw) : nullptr;
+	}
+	inline const void* area() const override { 
+		auto raw = get_raw();
+		return raw ? cow_ptr_of(const void, raw) : nullptr;
+	}
 
 	/// Get the size of the mapped area.
 	///

src/cow.cpp

@@ -37,11 +37,11 @@ Cow::~Cow(){}
 Cow Cow::from_raw(cow_t* owned) { if(cow_is_fake(owned)) throw "Trying to create real from fake raw"; else return Cow(owned); }
 
 Cow::Fake Cow::clone() const { return Fake::from_real(*this); }
-cow_t* Cow::get_raw() const { return super->ptr(); }
+cow_t* Cow::get_raw() const { return super ? super->ptr() : nullptr; }
 
-size_t Cow::size() const { return super->cow.size; }
+size_t Cow::size() const { return super ? super->cow.size : 0; }
 
-cow_t* Cow::raw() const { return &super->cow; }
+cow_t* Cow::raw() const { return super ? &super->cow : nullptr; }
 
 Cow::Fake::Fake(const Cow& copy) : Cow(copy), fake(cow_clone(copy.super->ptr())){}
 Cow::Fake::Fake(const Fake& copy) : Cow(copy), fake(cow_clone(copy.fake)){}//Fake(*static_cast<const Cow*>(&copy)){}