bump.h

//
// Created by 98max on 8/07/2026.
//
 
#ifndef MAXOS_ALLOCATOR_BUMP_H
#define MAXOS_ALLOCATOR_BUMP_H
 
#include <cstddef>
#include <cstdint>
 
#include <libcommon/assert.h>
 
#include <memory/allocator/allocator.h>
 
namespace MaxOS::memory::allocator {
 
 
    constexpr uint16_t EXPECTED_CANARY = 0xC0DE;                    
    constexpr size_t CHUNK_ALIGNMENT = 0x10;                        
 
    typedef struct alignas(CHUNK_ALIGNMENT) ChunkHeader {
 
        uint16_t canary;        
 
        ChunkHeader* next;      
        ChunkHeader* prev;      
 
        uint8_t allocated;        
        size_t size;            
 
        bool is_valid();
        ChunkHeader* prev_chunk();
        ChunkHeader* next_chunk();
 
    } chunk_header_t;
 
    constexpr size_t CHUNK_HEADER_SIZE = sizeof(chunk_header_t);    
 
    class BumpAllocator : public MemoryAllocator {
 
        private:
            chunk_header_t* m_first_memory_chunk = nullptr;
            chunk_header_t* m_last_memory_chunk = nullptr;
 
            void* expand_heap(size_t size) final;
            virtual void* allocate_extra_space(size_t requested_size, size_t& actual_size);
 
            bool m_setup = false;
 
 
        public:
            BumpAllocator();
            virtual ~BumpAllocator();
 
            void setup_region(uintptr_t address, size_t length) final;
 
            void* allocate(size_t size) final;
            void  unallocate(void* pointer) final;
 
            size_t amount_used() final;
            size_t align(size_t size) final;
 
    };
 
}
 
#endif //MAXOS_ALLOCATOR_BUMP_H