Removed rust version from master

Fortune for libcow's current commit: Future small blessing − 末小吉

.gitignore

@@ -4,3 +4,5 @@ cow-*
 obj/
 *~
 vgcore.*
+target/
+!cowslice/*.a

Makefile

@@ -5,7 +5,7 @@ PROJECT=cow
 AUTHOR=Avril (Flanchan) <flanchan@cumallover.me>
 
 VERSION_MAJOR=0
-VERSION_MINOR=2.0r1
+VERSION_MINOR=3.0
 VERSION=$(VERSION_MAJOR).$(VERSION_MINOR)
 
 ifeq ($(PREFIX),)

include/cow.h

@@ -35,6 +35,13 @@ typedef struct cow_mapped_slice cow_t;
 /// Writes to this instance pointer (`cow_ptr()`) are written to the allocated memory.
 /// Writes to any cloned instances do not propagate to this instance.
 cow_t* cow_create(size_t size);
+/// Create a new copy-on-write area of `size` bytes from file `fd`. 
+/// Writes to this instance pointer (`cow_ptr()`) are written to the allocated memory.
+/// Writes to any cloned instances do not propagate to this instance.
+///
+/// The resulting object does not own `fd`, but does own a duplicate of it.
+cow_t* cow_create_fd(int fd, size_t size);
+
 /// Free a cow area. This should be called on all clones before the parent of those clones is freed.
 void cow_free(cow_t* restrict cow);
 /// Create a clone of this instance. Any writes to the returned pointer will not be propagated to the input one.

include/cow.hpp

@@ -21,12 +21,15 @@ struct Cow : public _cow_util::Span<unsigned char> {
 	struct Fake;
 	Cow() = delete;
 
+	Cow(int fd, size_t size);
 	explicit Cow(size_t size);
+
 	Cow(Cow&& m);
 	virtual ~Cow();
 
 	virtual Fake clone() const;
 
+	protected:
 	inline void* area() override { 
 		auto raw = get_raw();
 		return raw ? cow_ptr(raw) : nullptr;
@@ -35,6 +38,7 @@ struct Cow : public _cow_util::Span<unsigned char> {
 		auto raw = get_raw();
 		return raw ? cow_ptr_of(const void, raw) : nullptr;
 	}
+	public:
 
 	/// Get the size of the mapped area.
 	///
@@ -59,6 +63,8 @@ struct Cow : public _cow_util::Span<unsigned char> {
 
 	protected:
 	Cow(const Cow& c);
+	explicit inline Cow(std::shared_ptr<_inner>&& super) : super(std::move(super)){}
+
 	const std::shared_ptr<_inner> super;
 	virtual cow_t* get_raw() const;
 
@@ -84,9 +90,3 @@ struct Cow::Fake : public Cow {
 	cow_t* const fake;
 };
 
-//TODO
-template<typename T>
-struct TypedCow : private Cow, public _cow_util::Span<T> {
-	struct Fake : private Cow::Fake, public _cow_util::Span<T>{};
-};
-

include/cow/area.hpp

@@ -5,9 +5,10 @@
 #include <utility>
 
 #include <cow.hpp>
+#include "slice.hpp"
 
 namespace _cow_util {
-	struct Area {
+	struct Area : public Span<unsigned char> {
 		Area() = delete;
 		
 		explicit Area(size_t sz);
@@ -30,7 +31,13 @@ namespace _cow_util {
 
 		inline cow_t* raw() const { return _area->raw(); }
 
+		inline size_t size() const override { return _area->size(); }
+		
 		~Area();
+		protected:
+		inline void* area() override { return _area->ptr(); }
+		inline const void* area() const override { return _area->ptr(); }
+
 		private:
 		const std::unique_ptr<Cow> _area;
 	};

include/cow/slice.hpp

@@ -4,17 +4,19 @@ namespace _cow_util {
 	/// A type that spans a sized region of memory
 	template<typename T>
 	struct Span {
+		protected:
 		virtual const void* area() const =0;
 		virtual void* area() = 0;
+		public:
 		virtual size_t size() const = 0;
 
-		inline T* ptr() { return (T*)area(); }
-		inline const T* ptr() const { return (const T*)area(); }
+		inline T* ptr() { return reinterpret_cast<T*>(area()); }
+		inline const T* ptr() const { return reinterpret_cast<const T*>(area()); }
 
 		inline size_t size_bytes() const { return size() * sizeof(T); }
 
-		inline unsigned char* as_bytes() { return (unsigned char*)area(); }
-		inline const unsigned char* as_bytes() const { return (const unsigned char*)area(); }
+		inline unsigned char* as_bytes() { return area_as<unsigned char>(); }
+		inline const unsigned char* as_bytes() const { return area_as<unsigned char>(); }
 
 		inline T& operator[](size_t index) {
 			if(index >= size()) throw "index out of range";
@@ -38,9 +40,9 @@ namespace _cow_util {
 		inline operator T*() { return &(*this)[0]; }
 
 		template<typename U>
-		inline U* area_as() requires(sizeof(T) % sizeof(U) == 0) { return (U*)area(); }
+		inline U* area_as() requires(sizeof(T) % sizeof(U) == 0) { return reinterpret_cast<U*>(area()); }
 		template<typename U>
-		inline const U* area_as() const requires(sizeof(T) % sizeof(U) == 0) { return (U*)area(); }
+		inline const U* area_as() const requires(sizeof(T) % sizeof(U) == 0) { return reinterpret_cast<const U*>(area()); }
 
 		template<typename U>
 		size_t size_as() const requires(sizeof(T) % sizeof(U) == 0) { return size_bytes() / sizeof(U); }
@@ -89,23 +91,24 @@ namespace _cow_util {
 		inline const Slice slice_wrap(ssize_t len) const { return slice_abs((size_t)wrap_len(len)); }
 
 		template<typename U>
-		inline Span<U>::Slice reinterpret() { return typename Span<U>::Slice((U*)area(), size_bytes() / sizeof(U)); }	
+		inline Span<U>::Slice reinterpret() { return typename Span<U>::Slice(area_as<U>(), size_bytes() / sizeof(U)); }	
 		template<typename U>
-		inline Span<const U>::Slice reinterpret() const { return typename Span<const U>::Slice((const U*)area(), size_bytes() / sizeof(U)); }
+		inline Span<const U>::Slice reinterpret() const { return typename Span<const U>::Slice(area_as<U>(), size_bytes() / sizeof(U)); }
 	};
 
 	/// A slice of memory with a backing pointer and size.
 	template<typename T>
 	struct Span<T>::Slice : public Span<T> {
-		inline Slice(T* ptr, size_t sz) : _area((void*)ptr), _size(sz){}
+		inline Slice(T* ptr, size_t sz) : _area(reinterpret_cast<void*>(ptr)), _size(sz){}
 		inline Slice(const Span<T>& slice) : _area(const_cast<void*>(slice.area())), _size(slice.size()){}
 		inline Slice(const Slice& copy) = default;
 		inline Slice(Slice&& copy) : _area(copy._area), _size(copy._size){ *const_cast<size_t*>(&copy._size) = 0; }
 		Slice() = delete;
 		
+		inline size_t size() const override { return _size; }
+		protected:
 		inline const void* area() const override { return _area; }
 		inline void* area() override { return _area; }
-		inline size_t size() const override { return _size; }
 	
 		private:
 		void* const _area;

include/cow/typed.hpp

@@ -0,0 +1,121 @@
+#pragma once
+
+#include <cow.hpp>
+#include <utility>
+
+template<typename T>
+struct TypedCow : public _cow_util::Span<T> {
+	struct Fake;
+
+	template<typename... Args>
+	inline TypedCow(size_t sz, Args&&... args) : real(Cow(sz * sizeof(T))) { init_copy( T(std::forward<Args>(args)...) ); }
+	inline TypedCow(size_t sz, const T& copy) : real(Cow(sz * sizeof(T))) { init_copy(copy); }
+	inline TypedCow(size_t sz) : TypedCow(sz, T()){}
+
+	inline virtual ~TypedCow() { uninit(); }
+
+	inline virtual Fake clone() const { return Fake(*this); }
+
+	inline virtual cow_t* raw() const { return real.raw(); }
+
+	inline size_t size() const { return real.size() / sizeof(T); }
+	protected:
+	//inline explicit TypedCow(const TypedCow<T>& unsafeCopy) : real(Cow(unsafeCopy.real)){}
+
+	inline virtual void* area() override { return reinterpret_cast<void*>( real.ptr() ); }
+	inline virtual const void* area() const override { return reinterpret_cast<const void*>( real.ptr() ); }
+
+	inline void init_copy(const T& copy_from) {
+		T* ptr = this->ptr();
+		for(size_t i=0;i<size();i++)
+			new ((void*)(ptr+i)) T(copy_from);
+
+	}
+	// UNSAFE: Explicitly calls destructors of each element in this instance.
+	inline void uninit() {
+		T* ptr = this->ptr();
+		if(!ptr) return;
+
+		for(size_t i=0;i<size();i++)
+			(ptr+i)->~T();
+	}
+	private:
+	Cow real;
+};
+template<typename T>
+struct TypedCow<T>::Fake : public TypedCow<T>  {
+//XXX: How THE FUCK do we initialise base's `real` here?????
+	Fake() = delete;
+
+	inline Fake(const Fake& copy) : fake(cow_clone(copy.fake)){}
+	inline Fake(Fake&& move) : fake(move.fake) { *const_cast<cow_t**>(&move.fake) = nullptr; }
+	inline Fake(const TypedCow<T>& clone) : fake(cow_clone(clone.raw())){}
+
+	inline cow_t* raw() const override { return fake; }
+	inline Fake clone() const override { return Fake(*this); }
+
+	inline ~Fake(){}
+
+	inline size_t size() const override { return fake ? cow_size(fake) : 0; }
+	protected:
+	inline void* area() override { return fake ? cow_ptr(fake) : nullptr; }
+	inline const void* area() const override { return fake ? cow_ptr_of(const void, fake) : nullptr; }
+	
+	private:
+	cow_t* const fake;
+};
+#if 0
+	struct Fake;
+	friend class Fake;
+
+	TypedCow() = delete;
+	inline TypedCow(TypedCow<T>&& move) : Cow(std::move(move.super)) { /* Moves the shared_ptr. No need to move the elements. */ }
+	// protected: copy
+	
+	inline TypedCow(size_t sz) : Cow(sz * sizeof(T)) { init_copy(T()); }
+	inline TypedCow(size_t sz, const T& copy_from) : TypedCow(sz) { init_copy(copy_from); }
+	//template<typename... Args>
+	//inline TypedCow(size_t sz, Args&&... args) : TypedCow(sz) { init_copy( T(std::forward<Args>(args)...) ); }
+
+	virtual inline ~TypedCow() { uninit(); }
+
+	inline Cow::Fake clone() const override { return Cow::clone(); }
+	inline Fake clone() const { return Fake(Cow::clone()); }
+
+	inline size_t size() const override { return Cow::size() / sizeof(T); }
+	
+	protected:
+	inline void* area() override { return Cow::area(); }
+	inline const void* area() const override { return Cow::area(); }
+	//// Should only be used for creating Fakes. Copies the refcounted pointer.
+	//inline TypedCow(const TypedCow<T>& copy) : Cow(copy.super) {}
+
+	// UNSAFE: Placement-new's copys of `copy_from` into `0..size()` of this instance.
+	inline void init_copy(const T& copy_from) {
+		T* ptr = _cow_util::Span<T>::ptr();
+		for(size_t i=0;i<size();i++)
+			new ((void*)(ptr+i)) T(copy_from);
+
+	}
+	// UNSAFE: Explicitly calls destructors of each element in this instance.
+	inline void uninit() {
+		T* ptr = _cow_util::Span<T>::ptr();
+		for(size_t i=0;i<size();i++)
+			(ptr+i)->~T();
+	}
+};
+
+template<typename T>
+struct TypedCow<T>::Fake : private Cow::Fake, public _cow_util::Span<T> {
+	Fake() = delete;
+	explicit inline Fake(Cow::Fake&& untyped) : Cow::Fake(untyped){}
+	inline Fake(const Fake& copy) : Fake(copy.Cow::Fake::clone()){}
+	inline Fake(Fake&& move) : Cow::Fake(std::move(move)) {}
+	inline ~Fake(){}
+
+	inline size_t size() const override { return Cow::Fake::size(); }
+	protected:
+	inline const void* area() const override { return Cow::Fake::area(); }
+	inline void* area() override { return Cow::Fake::area(); }
+};
+#endif

src/cow.c

@@ -76,13 +76,13 @@ size_t cow_size(const cow_t* cow)
 	return cow->size;
 }
 
-inline internal cow_t _cow_create_unboxed(size_t size)
+inline internal cow_t _cow_create_unboxed(int _fd, size_t size)
 {
 	cow_t ret;
 
 	ret.size = size;
 	if( (ret.poisoned = 
-		((ret.fd = shm_fd(size)) == -1))
+		((ret.fd = _fd < 0 ? shm_fd(size) : _fd) == -1))
 	) {
 		ret.origin = NULL;
 		return ret;
@@ -96,7 +96,14 @@ inline internal cow_t _cow_create_unboxed(size_t size)
 }
 cow_t* cow_create(size_t size)
 {	
-	return box_value(_cow_create_unboxed(size));
+	return box_value(_cow_create_unboxed(-1, size));
+}
+
+cow_t* cow_create_fd(int fd, size_t size)
+{
+	fd = dup(fd);
+	if(__builtin_expect(fd < 0, false)) return NULL;
+	return box_value(_cow_create_unboxed(fd, size));
 }
 
 inline internal void _cow_free_unboxed(const cow_t* cow)

src/cow.cpp

@@ -15,6 +15,7 @@ struct Cow::_inner {
 
 	~_inner();
 	_inner(size_t sz);
+	_inner(int fd, size_t sz);
 	_inner(cow_t* ptr);
 
 	_inner(const _inner& copy) = delete;
@@ -27,10 +28,12 @@ Cow::_inner::~_inner() {
 	_cow_free_unboxed(ptr());
 	cow.poisoned=true;
 }
-Cow::_inner::_inner(size_t sz) : cow(_cow_create_unboxed(sz)){
+Cow::_inner::_inner(int fd, size_t sz) : cow(_cow_create_unboxed(fd, sz)){
 	
 	if(UNLIKELY(cow.poisoned)) throw CowException(cow_err());
 }
+Cow::_inner::_inner(size_t sz) : _inner(-1, sz) {}
+
 Cow::_inner::_inner(cow_t* ptr) : cow(*ptr)
 {
 	free(ptr);
@@ -38,6 +41,7 @@ Cow::_inner::_inner(cow_t* ptr) : cow(*ptr)
 }
 
 Cow::Cow(size_t size) : super(std::make_shared<_inner>(size)){}
+Cow::Cow(int fd, size_t size) : super(std::make_shared<_inner>(fd, size)){}
 Cow::Cow(cow_t* raw) : super(std::make_shared<_inner>(raw)){}
 
 Cow::Cow(Cow&& m) : super(std::move(*const_cast<std::shared_ptr<_inner>*>(&m.super))){}

src/cow_t.h

@@ -44,7 +44,7 @@ _Static_assert
 		(offsetof(cow_t, size) == sizeof(void*), "`cow_t.size` should have an offset equal to `sizeof(void*)` or cow_size_unsafe() becomes UB.");
 #endif
 
-cow_t _cow_create_unboxed(size_t size) internal;
+cow_t _cow_create_unboxed(int rfd, size_t size) internal;
 void _cow_free_unboxed(const cow_t* cow) internal;
 
 #ifdef __cplusplus

src/test/main.cpp

@@ -8,6 +8,7 @@
 #include <vector>
 
 #include <cow/area.hpp>
+#include <cow/typed.hpp>
 
 using namespace _cow_util;
 
@@ -146,7 +147,7 @@ namespace Tiling {
 template<typename T = unsigned char>
 void print_slice(Slice<T> memory)
 {
-	printf("slice: { %p, %lu (%lu bytes) }\n", memory.area(), memory.size(), memory.size_bytes());
+	printf("slice: { %p, %lu (%lu bytes) }\n", memory.ptr(), memory.size(), memory.size_bytes());
 
 }
 
@@ -168,6 +169,12 @@ void moving_cow(Cow moved)
 	read_fake(moved);
 }
 
+void typed_cow()
+{
+	TypedCow<int> tc(1024);
+	
+}
+
 int main()
 {
 	Cow _area(4000);
@@ -203,7 +210,7 @@ int main()
 	
 	Cow::Fake clone = real;
 	printf("Fake size: %lu\n", clone.size());
-	printf("Fake ptr: %p\n", clone.area());
+	printf("Fake ptr: %p\n", clone.ptr());
 
 	read_fake(clone);
 	write_fake(clone, "hello fake!");
@@ -216,6 +223,7 @@ int main()
 	printf("First byte of: fake = %x\n", clone[0]);
 	read_fake(clone); //clone still functions because of refcount on origin.
 
+	typed_cow();
 	printf("Last error: %d, %s\n", cow_err(), *cow_err_msg(cow_err()));
 	try {
 		Cow should_fail(SIZE_MAX);