qt: Add API to get the context for a Job

* lang/qt/src/job.cpp,
lang/qt/src/job.h (Job::context): New.
* lang/qt/src/threadedjobmixin.cpp
(ThreadedJobMixin::~ThreadedJobMixin): New. Unregister context.
(ThreadedJobMixin::lateInitialization): Register context.
* NEWS: Update for cpp and qt.

--
The global map hack is necessary because the job class does
not know about the context which is held in threadedjobmixin.
Adding a virtual function in Job would be an ABI break which
I'd like to avoid at this point. Although QGpgME's API will
need a big ABI break to make it ABI maintainable. The virtual
jobs -> implementation classes are nearly unmaintainable ABI wise.

The context is exposed to provide more flexibility to users, e.g.
to add a passphrase callback or to set the sender in a context.

1 files changed, 4 insertions, 0 deletions

diff --git a/lang/qt/tests/t-tofuinfo.cpp b/lang/qt/tests/t-tofuinfo.cpp
index 2c87e4a9..f89e1c27 100644
--- a/lang/qt/tests/t-tofuinfo.cpp
+++ b/lang/qt/tests/t-tofuinfo.cpp
@@ -152,6 +152,10 @@ private Q_SLOTS:
         const QByteArray data1(testMsg1);
         QByteArray plaintext;
 
+        auto ctx = Job::context(job);
+        Q_ASSERT(ctx);
+        ctx->setSender("[email protected]");
+
         auto result = job->exec(data1, plaintext);
         delete job;