rubidium@6872: /* $Id$ */
rubidium@6872: 
rubidium@6872: /** @file alloc_func.hpp Functions related to the allocation of memory */
rubidium@6872: 
rubidium@6872: #ifndef ALLOC_FUNC_HPP
rubidium@6872: #define ALLOC_FUNC_HPP
rubidium@6872: 
rubidium@6872: /**
rubidium@6872:  * Simplified allocation function that allocates the specified number of
rubidium@6872:  * elements of the given type. It also explicitly casts it to the requested
rubidium@6872:  * type.
rubidium@6872:  * @note throws an error when there is no memory anymore.
rubidium@6872:  * @note the memory contains garbage data (i.e. possibly non-zero values).
rubidium@6872:  * @param T the type of the variable(s) to allocation.
rubidium@6872:  * @param num_elements the number of elements to allocate of the given type.
rubidium@6872:  * @return NULL when num_elements == 0, non-NULL otherwise.
rubidium@6872:  */
rubidium@6872: template <typename T> FORCEINLINE T* MallocT(size_t num_elements)
rubidium@6872: {
rubidium@6872: 	/*
rubidium@6872: 	 * MorphOS cannot handle 0 elements allocations, or rather that always
rubidium@6872: 	 * returns NULL. So we do that for *all* allocations, thus causing it
rubidium@6872: 	 * to behave the same on all OSes.
rubidium@6872: 	 */
rubidium@6872: 	if (num_elements == 0) return NULL;
rubidium@6872: 
rubidium@6872: 	T *t_ptr = (T*)malloc(num_elements * sizeof(T));
rubidium@6872: 	if (t_ptr == NULL) error("Out of memory. Cannot allocate %i bytes", num_elements * sizeof(T));
rubidium@6872: 	return t_ptr;
rubidium@6872: }
rubidium@6872: 
rubidium@6872: /**
rubidium@6872:  * Simplified allocation function that allocates the specified number of
rubidium@6872:  * elements of the given type. It also explicitly casts it to the requested
rubidium@6872:  * type.
rubidium@6872:  * @note throws an error when there is no memory anymore.
rubidium@6872:  * @note the memory contains all zero values.
rubidium@6872:  * @param T the type of the variable(s) to allocation.
rubidium@6872:  * @param num_elements the number of elements to allocate of the given type.
rubidium@6872:  * @return NULL when num_elements == 0, non-NULL otherwise.
rubidium@6872:  */
rubidium@6872: template <typename T> FORCEINLINE T* CallocT(size_t num_elements)
rubidium@6872: {
rubidium@6872: 	/*
rubidium@6872: 	 * MorphOS cannot handle 0 elements allocations, or rather that always
rubidium@6872: 	 * returns NULL. So we do that for *all* allocations, thus causing it
rubidium@6872: 	 * to behave the same on all OSes.
rubidium@6872: 	 */
rubidium@6872: 	if (num_elements == 0) return NULL;
rubidium@6872: 
rubidium@6872: 	T *t_ptr = (T*)calloc(num_elements, sizeof(T));
rubidium@6872: 	if (t_ptr == NULL) error("Out of memory. Cannot allocate %i bytes", num_elements * sizeof(T));
rubidium@6872: 	return t_ptr;
rubidium@6872: }
rubidium@6872: 
rubidium@6872: /**
rubidium@6872:  * Simplified reallocation function that allocates the specified number of
rubidium@6872:  * elements of the given type. It also explicitly casts it to the requested
rubidium@6872:  * type. It extends/shrinks the memory allocation given in t_ptr.
rubidium@6872:  * @note throws an error when there is no memory anymore.
rubidium@6872:  * @note the memory contains all zero values.
rubidium@6872:  * @param T the type of the variable(s) to allocation.
rubidium@6872:  * @param t_ptr the previous allocation to extend/shrink.
rubidium@6872:  * @param num_elements the number of elements to allocate of the given type.
rubidium@6872:  * @return NULL when num_elements == 0, non-NULL otherwise.
rubidium@6872:  */
rubidium@6872: template <typename T> FORCEINLINE T* ReallocT(T *t_ptr, size_t num_elements)
rubidium@6872: {
rubidium@6872: 	/*
rubidium@6872: 	 * MorphOS cannot handle 0 elements allocations, or rather that always
rubidium@6872: 	 * returns NULL. So we do that for *all* allocations, thus causing it
rubidium@6872: 	 * to behave the same on all OSes.
rubidium@6872: 	 */
rubidium@6872: 	if (num_elements == 0) {
rubidium@6872: 		free(t_ptr);
rubidium@6872: 		return NULL;
rubidium@6872: 	}
rubidium@6872: 
rubidium@6872: 	t_ptr = (T*)realloc(t_ptr, num_elements * sizeof(T));
rubidium@6872: 	if (t_ptr == NULL) error("Out of memory. Cannot reallocate %i bytes", num_elements * sizeof(T));
rubidium@6872: 	return t_ptr;
rubidium@6872: }
rubidium@6872: 
rubidium@6872: /**
rubidium@6872:  * A small 'wrapper' for allocations that can be done on most OSes on the
rubidium@6872:  * stack, but are just too large to fit in the stack on devices with a small
rubidium@6872:  * stack such as the NDS.
rubidium@6872:  * So when it is possible a stack allocation is made, otherwise a heap
rubidium@6872:  * allocation is made and this is freed once the struct goes out of scope.
rubidium@6872:  * @param T      the type to make the allocation for
rubidium@6872:  * @param length the amount of items to allocate
rubidium@6872:  */
rubidium@6872: template <typename T, size_t length>
rubidium@6872: struct SmallStackSafeStackAlloc {
rubidium@6872: #if !defined(__NDS__)
rubidium@6872: 	/** Storing the data on the stack */
rubidium@6872: 	T data[length];
rubidium@6872: #else
rubidium@6872: 	/** Storing it on the heap */
rubidium@6872: 	T *data;
rubidium@6872: 
rubidium@6872: 	/** Allocating the memory */
rubidium@6872: 	SmallStackSafeStackAlloc() : data(MallocT<T>(length)) {}
rubidium@6872: 	/** And freeing when it goes out of scope */
rubidium@6872: 	~SmallStackSafeStackAlloc() { free(data); }
rubidium@6872: #endif
rubidium@6872: 
rubidium@6872: 	/**
rubidium@6872: 	 * Gets a pointer to the data stored in this wrapper.
rubidium@6872: 	 * @return the pointer.
rubidium@6872: 	 */
rubidium@6872: 	operator T* () { return data; }
rubidium@6872: };
rubidium@6872: 
rubidium@6872: #endif /* ALLOC_FUNC_HPP */