Function realloc

src/pointers/malloc.py:148–185

Resize a memory block created by malloc. Args: target: Pointer to reallocate. size: New allocation size. Returns: Original object. Raises: InvalidSizeError: Object inside allocation is larger than attempted reallocation. AllocationErr

(target: A, size: int)

@handle
def realloc(target: A, size: int) -> A:
    """Resize a memory block created by malloc.

    Args:
        target: Pointer to reallocate.
        size: New allocation size.

    Returns:
        Original object.

    Raises:
        InvalidSizeError: Object inside allocation is larger than attempted reallocation.
        AllocationError: Raised when allocation fails, presumably due to no memory.

    Example:
        ```py
        ptr = malloc(1)
        realloc(ptr, 2)
        ```
    """  # noqa
    if type(target) is StackAllocatedPointer:
        raise TypeError("pointers to items on the stack may not be resized")

    tsize: int = sys.getsizeof(~target)

    if target.assigned and (tsize > size):
        raise InvalidSizeError(
            f"object inside memory is of size {tsize}, so memory cannot be set to size {size}",  # noqa
        )

    addr = c_realloc(target.address, size)

    if not addr:
        raise AllocationError("failed to resize memory")

    target.size = size
    target.address = addr
    return target