PAM Programming Manual

Link-Level Programming Examples
PAM Programming Manual—142482
B-17
Finding a Free Buffer
Finding a Free Buffer
The application must provide a function that allows it to find a free buffer to contain the
aggregate SDU.
#pragma page “FUNCTION: Find Free Buffer”
/* ----------------------------------------------------------------
FUNCTION: Find Free Buffer
---------------------------------------------------------------- */
int Find_Free_Buffer ( buffer_lst_ndx )
long *buffer_lst_ndx;
{
*buffer_lst_ndx = 0;
while ( *buffer_lst_ndx < ( NoWait_Depth ) )
{
if (!(buffer_lst [ *buffer_lst_ndx ].in_use_flag))
return True;
*buffer_lst_ndx = ( *buffer_lst_ndx + 1 );
};
return (False);
}
Building an Aggregate SDU
The application must provide a function for building the aggregate SDU.
#pragma page “FUNCTION: Build Aggr SDU”
/* ----------------------------------------------------------------
FUNCTION: Build Aggr SDU
---------------------------------------------------------------- */
int Build_Aggr_SDU ( Aggr_SDU_buf )
char *Aggr_SDU_buf;
{
int SDU_ndx;
int frmt_error;
int data_offset_b;
int count;
frmt_error = ZL2S_FRMT_AGGR_SDU_HDR_
( (char *)Aggr_SDU_buf, Max_Req_Size );
if ( frmt_error != zl2s_err_frmt_ok )
{
fprintf(stdout,”Aggr SDU Hdr Error:%d\n”, frmt_error);
exit(Abend_exit);
}
/* -------------- In case there are 0 SDUs to build ------------ */
data_offset_b = sizeof (struct zl2s_ddl_aggr_sdu_hdr_def);
for (SDU_ndx = 1; SDU_ndx <= SDU_Cnt; SDU_ndx++)
{
frmt_error = ZL2S_FRMT_SDU_HDR_ ( (char *)Aggr_SDU_buf,
Port_Type,
Command_Code,
P_F_Flag,