Method remapFile

src/common/isc_sync.cpp:2516–2571

#ifdef HAVE_MMAP
#define ISC_REMAP_FILE_DEFINED
bool SharedMemoryBase::remapFile(CheckStatusWrapper* statusVector, ULONG new_length, bool flag)
{
/**************************************
 *
 *	I S C _ r e m a p _ f i l e		( U N I X - m m a p )
 *
 **************************************
 *
 * Functional description
 *	Try to re-map a given file.
 *
 **************************************/
	if (!new_length)
	{
		error(statusVector, "Zero new_length is requested", 0);
		return false;
	}

	if (flag)
	{
		new_length = FB_ALIGN(new_length, getSystemPageSize(statusVector));

		FB_UNUSED(os_utils::ftruncate(mainLock->getFd(), new_length));

		if (new_length > sh_mem_length_mapped)
		{
			if (!allocFileSpace(mainLock->getFd(), sh_mem_length_mapped,
				new_length - sh_mem_length_mapped, statusVector))
			{
				return false;
			}
		}
	}

	MemoryHeader* const address = (MemoryHeader*) os_utils::mmap(0, new_length,
		PROT_READ | PROT_WRITE, MAP_SHARED, mainLock->getFd(), 0);

	if ((U_IPTR) address == (U_IPTR) -1)
	{
		error(statusVector, "mmap() failed", errno);
		return false;
	}

	munmap(sh_mem_header, sh_mem_length_mapped);

	IPC_TRACE(("ISC_remap_file %p to %p %d\n", sh_mem_header, address, new_length));

	sh_mem_header = (MemoryHeader*) address;
	sh_mem_length_mapped = new_length;

#if defined(HAVE_SHARED_MUTEX_SECTION) && !defined(USE_MUTEX_MAP)
	sh_mem_mutex = &sh_mem_header->mhb_mutex;
#endif

	return address;
}
#endif // HAVE_MMAP
#endif // UNIX