kernel: Add warning method to notifications

This commit is part of the libbitcoinkernel project and seeks to remove
the ChainstateManager's and, more generally, the kernel library's
dependency on interface_ui with options methods in this and the following
few commits. By removing interface_ui from the kernel library, its
dependency on boost is reduced to just boost::multi_index.

The DoWarning and AlertNotify functions are moved out of the
validation.cpp file, which removes its dependency on interface_ui as
well as util/system.

1 files changed, 1 insertions, 0 deletions

diff --git a/src/kernel/notifications_interface.h b/src/kernel/notifications_interface.h
index 1d5643ca07..48248e9aa0 100644
--- a/src/kernel/notifications_interface.h
+++ b/src/kernel/notifications_interface.h
@@ -26,6 +26,7 @@ public:
     virtual void blockTip(SynchronizationState state, CBlockIndex& index) {}
     virtual void headerTip(SynchronizationState state, int64_t height, int64_t timestamp, bool presync) {}
     virtual void progress(const bilingual_str& title, int progress_percent, bool resume_possible) {}
+    virtual void warning(const bilingual_str& warning) {}
 };
 } // namespace kernel