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Dialogic® Distributed Signaling Interface (DSI) - Signaling and SS7 Products

How a Dialogic® Global Call application can read the SS7 ISUP or TUP message that triggered a GCEV_ event.

GC_PARM gcs7_parm; 
gcs7_parm.intvalue = 8;


if(gc_SetParm(dev,GCPR_RECEIVE_INFO_BUF,gcs7_parm)!=GC_SUCCESS){ 
  // print_GC_error( dev, "gc_SetParm"); 
} 
  else { 
  // LOG_TRACE(dev, "gc_SetParm( )"); 
}

char buffer[350]; // Should be enough to hold the Global Call SS7 SIGINFO header + any ISUP message 
S7_SIGINFO_BLK *blk_p = (S7_SIGINFO_BLK *)buffer; 
blk_p->length = 350;
int t_res = gc_GetSigInfo(dev, buffer, 0, &metaevt); 
if(t_res == 0){ 
  // LOG_TRACE(dev, "gc_GetSigInfo() succeeded: length of SigInfo block [%d]; ISUP primitive [%d]", blk_p->length, blk_p->prim); 
  Parse(blk_p); 
} else { 
  //print_GC_error( dev, "gc_GetSigInfo"); 
} 

static void Parse(S7_SIGINFO_BLK *a_blk_p) 
{ 
  printf("gc_GetSigInfo() succeeded: length of SigInfo block [%d]; ISUP primitive [%d]\n", a_blk_p->length, a_blk_p->prim); 
  S7_IE *t_data_p = &a_blk_p->data; 
  int t_CurrIESize = sizeof(S7_IE) - 1 + t_data_p->length; 
  int t_BytesLeft = a_blk_p->length-2; 
  while((t_BytesLeft >= sizeof(S7_IE)) && (t_BytesLeft >= t_CurrIESize)){ 
    unsigned char t_ByteValue; 
    unsigned short t_ShortValue; 
    unsigned int t_IntValue; 
    printf("Found parameter %d [0x%x]; length=%d; ", t_data_p->parm, t_data_p->parm, t_data_p->length); 
    switch(t_data_p->length){ 
      case 0: 
        printf("Parsing error: length=0\n"); 
        break; 
      case 1: 
        t_ByteValue = t_data_p->value; 
        memcpy(&t_ByteValue, &t_data_p->value, 1); 
        printf("value = [0x%x]\n", t_ByteValue); 
        break; 
      case 2: 
        memcpy(&t_ShortValue, &t_data_p->value, 2); 
        printf("value = [0x%x]\n", t_ShortValue); 
        break; 
      case 4: 
        memcpy(&t_IntValue, &t_data_p->value, 4); 
        printf("value = [0x%x]\n", t_IntValue); 
        break; 
      default: //more 
        // eventually write suitable code here to print data for IE of 3 bytes or of more than 
        // 4 bytes of length ...
      break; 
    } 
    //next step 
    t_BytesLeft -= t_CurrIESize; 
    t_data_p = (S7_IE*)((char*)t_data_p + t_CurrIESize); 
    t_CurrIESize = sizeof(S7_IE) - 1 + t_data_p->length; 
  } 
}