#include "memorymanagement.h"

#include "string.h"

#include "kernel.h"

void memory_manager_init( memory_manager_t *memory_manager, size_t offset, size_t size )
{
	memset( memory_manager, 0, sizeof( memory_manager_t ) );

	memory_manager->offset = offset;
	memory_manager->size = size;
	memory_manager->free_ptr = offset;
}

void *memory_manager_allocate( memory_manager_t *memory_manager, size_t size )
{
	void *p = NULL;

	if( memory_manager->free_ptr - memory_manager->offset + size > memory_manager->size ) {
		kernel_panic( "Heap allocation out of memory (requested %d bytes, available %d)",
			size, size - ( memory_manager->free_ptr - memory_manager->offset ) - 1 );
	}

	p = (void *)memory_manager->free_ptr;
	memory_manager->free_ptr += size;

	return p;
}

void memory_manager_deallocate( memory_manager_t *memory_manager, void **p )
{
	if( *p == NULL ) {
		kernel_panic( "Double free of pointer 0x%X in heap", *p );
	}

	*p = NULL;
}