Setting foreign.restricted to permit doesn't work

[Ty Young]

On 4/23/20 4:29 PM, Maurizio Cimadamore wrote:
>
> On 23/04/2020 22:24, Ty Young wrote:
>>
>> On 4/23/20 4:14 PM, Maurizio Cimadamore wrote:
>>> This is as expected. The property was always intended to be an 
>>> opt-in - e.g. a replacement for a command line flag. Because of an 
>>> issue in the implementation, it was possible to bypass the flag and 
>>> set the property in a static initializer. Now the implementation 
>>> correctly reads the value of the property at VM startup.
>>>
>>> In short - you need the command line flag.
>>
>>
>> The MemorySegment.ofNativeRestricted does not mention this currently. 
>> Could extra clarification be added?
> I guess this will probably change few times during the code review I 
> just posted for integrating what we have into jdk/jdk :-) - I'll keep 
> the suggestion in mind.
>>
>>
>> What is the runtime argument? --foreign-restricted=permit?
>
> -Dforeign.restricted=permit


OK, that works.


Next question: what's going on with MemoryAddress handles? Presumably 
you need to do:


private static final VarHandle POINTER_HANDLE = 
MemoryHandles.varHandle(LONG_HANDLE, ByteOrder.nativeOrder());


To do what you could before. Is this correct and Is this because of all 
the new fancy methods added to MethodHandles? It surely can't be for 
type safety since VarHandles has none.




>
> Maurizio
>
>>
>>
>>>
>>> Maurizio
>>>
>>> On 23/04/2020 22:05, Ty Young wrote:
>>>> Setting "foreign.restricted" to "permit":
>>>>
>>>>
>>>> System.setProperty("foreign.restricted", "permit");
>>>>
>>>>
>>>> fails on the latest source builds. This is before any unsafe 
>>>> operations in my JavaFX application or even my "Test" runnable 
>>>> class for bindings. Call trace:
>>>>
>>>>
>>>> Caused by: java.lang.IllegalAccessError: Illegal access to 
>>>> restricted foreign method: MemorySegment.ofNativeRestricted ; 
>>>> system property 'foreign.restricted' is set to 'deny'
>>>>     at 
>>>> jdk.incubator.foreign/jdk.internal.foreign.Utils.throwIllegalAccessError(Utils.java:99)
>>>>     at 
>>>> jdk.incubator.foreign/jdk.internal.foreign.Utils.checkRestrictedAccess(Utils.java:84)
>>>>     at 
>>>> jdk.incubator.foreign/jdk.incubator.foreign.MemorySegment.ofNativeRestricted(MemorySegment.java:540)
>>>>     at 
>>>> org.goliath.crosspoint/org.goliath.crosspoint.abstracts.ThreadSafeNativeNumber.<init>(ThreadSafeNativeNumber.java:20)
>>>>     at 
>>>> org.goliath.crosspoint/org.goliath.crosspoint.abstracts.NativeNumber.<init>(NativeNumber.java:66)
>>>>     at 
>>>> org.goliath.crosspoint/org.goliath.crosspoint.numbers.NativeLong.<init>(NativeLong.java:11)
>>>>
>>>>
>>>>