Question

I’m trying to convert this function to JNA:

        DWORD WINAPI WlanHostedNetworkSetProperty(
        __in        HANDLE hClientHandle,
        __in        WLAN_HOSTED_NETWORK_OPCODE OpCode,
        __in        DWORD dwDataSize,
        __in        PVOID pvData,
        __out_opt   PWLAN_HOSTED_NETWORK_REASON pFailReason,
        __reserved  PVOID pvReserved
        );

As I have now:

     int WlanHostedNetworpSetProperty(HANDLE hClientHandle, IntByReference OpCode,int dwDataSize, Pointer pvData, IntByReference pFailReason, Pointer pvReserved);

Which should be right.

However when OpCode is wlan_hosted_network_opcode_enable, aka 3, it wants the pvData to be BOOL. I read that BOOL is an integer, but doing pvData.setInteger(1) will crash the application. Any help would be great.

The crash is an EXCEPTION_ACCESS_VIOLATION.

Answer 1

According to MSDN, when the OpCode is wlan_hosted_network_opcode_enable:

A pointer to BOOL is passed in the pvData parameter.

Note that it’s a pointer to BOOL, not an actual BOOL value, that is needed.

As you found, changing to an IntByReference solved the problem, likely because an int and BOOL are the same size on your platform, and because now you’re passing a valid pointer.