求大神解释下这段程序

只看该作者 · 2015-10-19 14:46

////////////////////////////////////////////////////////////////////////////////////////////////////
// FUNCT:
//  Mesh_Checkqueue
// DESCR:
//  Check if the corresponding bit of wanted node has been set or not.
//  Check whether specified node is already in the queue.
//  If set, return 1. Else return 0.
// INPUTS:
//  node - node ID.
//  parray - indication array
// OUTPUTS:
//  node  - ID of the node.
// RETURN:
//  TRUE or FALSE indicate whether specified node is in the queue.
// Considerations:
//  None.
////////////////////////////////////////////////////////////////////////////////////////////////////
uint8 Mesh_Checkqueue(address_size node, const uint8* parray)
{
address_size i;
address_size j;
address_size k;
node --; // node - 1 to align with the corresponding bit in the array
i = node / 8;
j = node % 8;
k = 0x01 << j;
if((parray[i] & k) != 0)
{
  return TRUE;
}
else
  return FALSE;
}