Class ShmSafeUnmanagedChunk

• Defined in File shm_safe_unmanaged_chunk.hpp

Class Documentation

class ShmSafeUnmanagedChunk

This class to safely store a chunk in shared memory. To be able to do so, torn writes/reads need to prevented, since they create Frankenstein objects. Therefore, the class must not be larger than 64 bits and trivially copy-able in case an application dies while writing this and RouDi needs to clean up.

Public Functions

ShmSafeUnmanagedChunk() noexcept = default

ShmSafeUnmanagedChunk(SharedChunk chunk) noexcept

takes a SharedChunk without decrementing the chunk reference counter

SharedChunk releaseToSharedChunk() noexcept

Creates a SharedChunk without incrementing the chunk reference counter and invalidates itself.

SharedChunk cloneToSharedChunk() noexcept

Creates a SharedChunk with incrementing the chunk reference counter and does not invalidate itself.

bool isLogicalNullptr() const noexcept

Checks if the underlying RelativePointerData to the chunk is logically a nullptr.

Returns:

true if logically a nullptr otherwise false

ChunkHeader *getChunkHeader() noexcept

Access to the ChunkHeader of the underlying chunk.

Returns:

the pointer to the ChunkHeader of the underlying chunk or nullptr if isLogicalNullptr would return true

const ChunkHeader *getChunkHeader() const noexcept

const access to the ChunkHeader of the underlying chunk

Returns:

the const pointer to the ChunkHeader of the underlying chunk or nullptr if isLogicalNullptr would return true

bool isNotLogicalNullptrAndHasNoOtherOwners() const noexcept

Checks if the underlying RelativePointerData to the chunk is neither logically a nullptr nor that the chunk has other owner.

Returns:

true if neither logically a nullptr nor other owner chunk owners present, otherwise false