- switch(bchannel->b_mode) {
- case 0:
- for (i = 0; i < len; i++)
- *p++ = flip_bits[*data++];
- frm->prim = DL_DATA_REQ;
- break;
- case 1:
- for (i = 0; i < len; i++)
- *p++ = flip_bits[*data++];
- frm->prim = PH_DATA_REQ;
- break;
- case 2:
- memcpy(p, data, len);
- frm->prim = DL_DATA_REQ;
- break;
- case 3:
- memcpy(p, data, len);
- frm->prim = PH_DATA_REQ;
- break;
- }
+ if (data) {
+ switch(bchannel->b_mode) {
+ case 0:
+ for (i = 0; i < len; i++)
+ *p++ = flip_bits[*data++];
+ frm->prim = DL_DATA_REQ;
+ break;
+ case 1:
+ for (i = 0; i < len; i++)
+ *p++ = flip_bits[*data++];
+ frm->prim = PH_DATA_REQ;
+ break;
+ case 2:
+ memcpy(p, data, len);
+ frm->prim = DL_DATA_REQ;
+ break;
+ case 3:
+ memcpy(p, data, len);
+ frm->prim = PH_DATA_REQ;
+ break;
+ }
+ } else
+ memset(p, flip_bits[(options.law=='a')?0x2a:0xff], len);