Hi James,
On Sat, May 28, 2016 at 12:53:14PM -0700, James Howarth wrote:
> Hi,
>
> Looking at the peripheral callback gatt_svr_chr_access_gatt, is there a way
> to determine the length of data received?
>
> Here's the whole function definition.
>
> static int
> gatt_svr_chr_access_gatt(uint16_t conn_handle, uint16_t attr_handle,
> uint8_t op,
> union ble_gatt_access_ctxt *ctxt, void *arg)
The length of the received data is contained in the ctxt->chr_access.len
field. For example, bleprph handles an incoming write of the
gap-reconnect-address characteristic as follows:
case BLE_GAP_CHR_UUID16_RECONNECT_ADDR:
assert(op == BLE_GATT_ACCESS_OP_WRITE_CHR);
if (ctxt->chr_access.len != sizeof bleprph_reconnect_addr) {
return BLE_ATT_ERR_INVALID_ATTR_VALUE_LEN;
}
memcpy(bleprph_reconnect_addr, ctxt->chr_access.data,
sizeof bleprph_reconnect_addr);
break;
The code validates the length of the incoming data immediately after the
assert() invocation.
Chris
