Some conditions in shm_toc_insert and shm_toc_allocate are bogus, like: if (toc_bytes + nbytes > total_bytes || toc_bytes + nbytes < toc_bytes) Remove the condition `toc_bytes + nbytes < toc_bytes` and take a sizeof(shm_entry) into account in shm_toc_allocate though shm_toc_allocate does that too.
shm_toc_insert does that too, and we can report error earlier.
I don't think we should consider sizeof(shm_toc_entry) in the 'if' condition in shm_toc_allocate, as this function is not in charge of allocating a new TOC entry. That's what shm_toc_insert does.
