#ifndef HAKMEM_TINY_PTR_CONVERT_BOX_H
#define HAKMEM_TINY_PTR_CONVERT_BOX_H

#include <stddef.h>

// Purpose: Zero-overhead inline conversions between BASE and USER pointers
// Contract: Header is stored at offset -1 from USER pointer
//
// Example:
//   - Allocation: base → user (user = base + 1)
//   - Deallocation: user → base (base = user - 1)
//
// Offset definition (centralized for future extension)
#define TINY_HEADER_OFFSET 1

// Direct inline macros (zero cost, lvalue compatible in some contexts)
#define tiny_base_to_user_inline(base) \
    ((void*)((char*)(base) + TINY_HEADER_OFFSET))

#define tiny_user_to_base_inline(user) \
    ((void*)((char*)(user) - TINY_HEADER_OFFSET))

// Verbose variants (for clarity in critical paths)
static inline void* tiny_base_to_user(void* base) {
    return tiny_base_to_user_inline(base);
}

static inline void* tiny_user_to_base(void* user) {
    return tiny_user_to_base_inline(user);
}

#endif // HAKMEM_TINY_PTR_CONVERT_BOX_H