RFR: 8009550: PlatformPCSC should load versioned so [v2]

[Andrew John Hughes]

On Tue, 5 Sep 2023 10:17:31 GMT, Andrew John Hughes <andrew at openjdk.org> wrote:

>> There is a long standing limitation in the UNIX smartcardio implementation which means it will only look for the `pcsclite` library in two locations; `/usr/lib` and `/usr/local/lib`. It also only searches for an unversioned library.
>> 
>> On systems that separate libraries from development headers in separate subpackages, the unversioned library is only installed by the `-devel` package, which rarely happens unless the user wants to write their own application using the libpcsclite headers or build someone else's code themselves. An example of this is the [pcsc-lite-libs package on Fedora](https://koji.fedoraproject.org/koji/rpminfo?rpmID=35258843)
>> 
>> On Debian-based systems, there is also the issue that libraries are now placed inside a subdirectory using a [tuple](https://wiki.debian.org/Multiarch/Tuples) consisting of the instruction set, syscall ABI and libc e.g. `x86_64-linux-gnu`.  So it will not only fail to find the library when only the versioned library is installed (e.g. [libpcsclite1](https://packages.ubuntu.com/kinetic/amd64/libpcsclite1/filelist)) but also when the dev package is also installed (e.g. [libpcsclite-dev](https://packages.ubuntu.com/kinetic/amd64/libpcsclite-dev/filelist)), because the file is in e.g. `/usr/lib/x86_64-linux-gnu/libpcsclite.so`
>> 
>> This patch makes both cases work. It prefers versioned libraries, as potentially a `libpcsclite.so.2` could become available with a different ABI that the JDK can not work with.  All cases that worked before with just `libpcsclite.so` will still work, but it should also now pick up the library on many additional systems.
>> 
>> A much simpler patch (search for the versioned symlink instead of unversioned) has been [in the Fedora and RHEL packages for nearly a decade](https://bugzilla.redhat.com/show_bug.cgi?id=910107), and an earlier version of this patch with Debian support has been used in IcedTea builds since 2015. It would be nice to finally fix this upstream.
>> 
>> Testing:
>> 
>> Test case:
>> ~~~
>> import java.lang.reflect.Method;
>> 
>> public class TestPlatformPCSC {
>>     public static void main(String[] args)
>>     throws Exception {
>>         Class<?> cls = Class.forName("sun.security.smartcardio.PlatformPCSC");
>>         Method m = cls.getDeclaredMethod("getLibraryName");
>>         m.setAccessible(true);
>>         System.err.println(m.invoke(null));
>>     }
>> }
>> ~~~
>> 
>> 1. With `libpcsclite.so.1` available:
>> ~~~
>> $ ~/builder/trunk/images/jdk/bin/java --add-opens java.smartc...
>
> Andrew John Hughes has updated the pull request incrementally with one additional commit since the last revision:
> 
>   Drop outdated kfreebsd case and document arch template and arm

No problem. I know you were away for a while.

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PR Comment: https://git.openjdk.org/jdk/pull/15409#issuecomment-1786320964