Function alloc_request

src/remote/server/server.cpp:1523–1585

static server_req_t* alloc_request()
{
/**************************************
 *
 *	a l l o c _ r e q u e s t
 *
 **************************************
 *
 * Functional description
 *	Get request block from the free blocks list,
 *	if empty - allocate the new one.
 *
 **************************************/
	MutexEnsureUnlock queGuard(request_que_mutex, FB_FUNCTION);
	queGuard.enter();

	server_req_t* request = free_requests;
#if defined(DEV_BUILD) && defined(DEBUG)
	int request_count = 0;
#endif

	// Allocate a memory block to store the request in
	if (request)
	{
		free_requests = request->req_next;
	}
	else
	{
		// No block on the free list - allocate some new memory
		for (;;)
		{
			try
			{
				request = FB_NEW server_req_t;
				break;
			}
			catch (const BadAlloc&)
			{ }

#if defined(DEV_BUILD) && defined(DEBUG)
			if (request_count++ > 4)
				BadAlloc::raise();
#endif

			// System is out of memory, let's delay processing this
			// request and hope another thread will free memory or
			// request blocks that we can then use.

			queGuard.leave();
			Thread::sleep(1 * 1000);
			queGuard.enter();
		}
		zap_packet(&request->req_send, true);
		zap_packet(&request->req_receive, true);
#ifdef DEBUG_REMOTE_MEMORY
		printf("alloc_request         allocate request %x\n", request);
#endif
	}