Function pqAllocCmdQueueEntry

src/interfaces/libpq/fe-exec.c:1246–1270

* pqAllocCmdQueueEntry * Get a command queue entry for caller to fill. * * If the recycle queue has a free element, that is returned; if not, a * fresh one is allocated. Caller is responsible for adding it to the * command queue (pqAppendCmdQueueEntry) once the struct is filled in, or * releasing the memory (pqRecycleCmdQueueEntry) if an error occurs. * * If allocation fails, sets the er

 * If allocation fails, sets the error message and returns NULL.
 */
PGcmdQueueEntry *
pqAllocCmdQueueEntry(PGconn *conn)
{
	PGcmdQueueEntry *entry;

	if (conn->cmd_queue_recycle == NULL)
	{
		entry = (PGcmdQueueEntry *) malloc(sizeof(PGcmdQueueEntry));
		if (entry == NULL)
		{
			appendPQExpBufferStr(&conn->errorMessage,
								 libpq_gettext("out of memory\n"));
			return NULL;
		}
	}
	else
	{
		entry = conn->cmd_queue_recycle;
		conn->cmd_queue_recycle = entry->next;
	}
	entry->next = NULL;
	entry->query = NULL;

	return entry;
}

/*
 * pqAppendCmdQueueEntry