[foreign-jextract] Generated getters and setters do not include offsets

[Filip Krakowski]

Hi Jorn,

I just gave it a try and it looks good.

Now unfortunately I have another bug. A source file (in my case 
"constants$3") is referencing a private field in another source file 
("constants$2"). It looks like the VarHandles for the struct got split 
in two different source files. I am using the same header file 
(https://github.com/linux-rdma/rdma-core/blob/master/libibverbs/verbs.h) 
as before.

constants$2.java

    private static final MemoryLayout
    ib_uverbs_alloc_mw_resp$struct$LAYOUT_ =MemoryLayout.ofStruct(
         C_INT.withName("mw_handle"),
         C_INT.withName("rkey"),
         MemoryLayout.ofSequence(0,C_LONG).withName("driver_data")
    ).withName("ib_uverbs_alloc_mw_resp");
    public static jdk.incubator.foreign.MemoryLayout
    ib_uverbs_alloc_mw_resp$struct$LAYOUT() {return ib_uverbs_alloc_mw_resp$struct$LAYOUT_; }

    private static final MemoryLayout
    ib_uverbs_alloc_mw_resp$mw_handle$LAYOUT_ =C_INT;
    public static jdk.incubator.foreign.MemoryLayout
    ib_uverbs_alloc_mw_resp$mw_handle$LAYOUT() {return ib_uverbs_alloc_mw_resp$mw_handle$LAYOUT_; }

    private static final VarHandle ib_uverbs_alloc_mw_resp$mw_handle$VH_ =ib_uverbs_alloc_mw_resp$struct$LAYOUT_.varHandle(int.class,MemoryLayout.PathElement.groupElement("mw_handle"));
    public static java.lang.invoke.VarHandle
    ib_uverbs_alloc_mw_resp$mw_handle$VH() {return ib_uverbs_alloc_mw_resp$mw_handle$VH_; }


constants$3.java

    private static final MemoryLayout ib_uverbs_alloc_mw_resp$rkey$LAYOUT_ =C_INT;
    public static jdk.incubator.foreign.MemoryLayout
    ib_uverbs_alloc_mw_resp$rkey$LAYOUT() {return ib_uverbs_alloc_mw_resp$rkey$LAYOUT_; }

    private static final VarHandle ib_uverbs_alloc_mw_resp$rkey$VH_ =ib_uverbs_alloc_mw_resp$struct$LAYOUT_.varHandle(int.class,MemoryLayout.PathElement.groupElement("rkey"));
    public static java.lang.invoke.VarHandle ib_uverbs_alloc_mw_resp$rkey$VH() {return ib_uverbs_alloc_mw_resp$rkey$VH_; }


Since "ib_uverbs_alloc_mw_resp$struct$LAYOUT_" is private within 
"constants$2" the code does not compile.

Best regards,
Filip

On 01.09.20 15:08, Jorn Vernee wrote:
> Hi Filip,
>
> This issue should now be fixed [1], can you give it a try?
>
> Thanks,
> Jorn
>
> [1] : https://github.com/openjdk/panama-foreign/commit/afdbc657
>
> On 31/08/2020 12:35, Filip Krakowski wrote:
>> Hi,
>>
>> I just noticed that jextract's generated getters and setters always 
>> access the provided MemorySegment at offset 0. This looks like a bug 
>> to me.
>>
>> This is the struct I used to reproduce this issue.
>>
>>    struct coordinate {
>>       int x;
>>       int y;
>>    };
>>
>>
>> And this is the code jextract generated from it (source mode).
>>
>>    private static final MemoryLayout coordinate$struct$LAYOUT_ 
>> =MemoryLayout.ofStruct(
>>         C_INT.withName("x"),
>>         C_INT.withName("y")
>>    ).withName("coordinate");
>>
>>    public static jdk.incubator.foreign.MemoryLayout
>>    coordinate$struct$LAYOUT() {return coordinate$struct$LAYOUT_; }
>>
>>    private static final MemoryLayout coordinate$x$LAYOUT_ =C_INT;
>>    public static jdk.incubator.foreign.MemoryLayout 
>> coordinate$x$LAYOUT() {return coordinate$x$LAYOUT_; }
>>
>>    private static final VarHandle coordinate$x$VH_ 
>> =coordinate$x$LAYOUT_.varHandle(int.class);
>>    public static java.lang.invoke.VarHandle coordinate$x$VH() {return 
>> coordinate$x$VH_; }
>>
>>    private static final MemoryLayout coordinate$y$LAYOUT_ =C_INT;
>>    public static jdk.incubator.foreign.MemoryLayout 
>> coordinate$y$LAYOUT() {return coordinate$y$LAYOUT_; }
>>
>>    private static final VarHandle coordinate$y$VH_ 
>> =coordinate$y$LAYOUT_.varHandle(int.class);
>>    public static java.lang.invoke.VarHandle coordinate$y$VH() {return 
>> coordinate$y$VH_; }
>>
>>
>> Here I allocate the struct, set both fields and print them afterwards.
>>
>>    try (var segment =coordinate.allocate()) {
>>         coordinate.x$set(segment,1);
>>         coordinate.y$set(segment,2);
>>
>>         System.out.println(coordinate.x$get(segment));
>>         System.out.println(coordinate.y$get(segment));
>>    }
>>
>>
>> This will print "2" twice, although "x" should be set to "1" in my 
>> understanding.
>>
>> I am using the latest build (commit 
>> 4d7888c040767760b6250130ef6024ea16b43461).
>>
>>
>> Best regards,
>> Filip