Don't lose acquirement if you disconnect at the prompt.

People are quite likely to stop and think, consult ##crawl, etc.  And
thinking is tiresome, folks get distracted...  and then it's a time-out,
they turn the computer without thinking and go to sleep, etc.

This adds a new mechanism: "uncancellables", which allows an action to
restart when the game is loaded back.

1 files changed, 19 insertions, 0 deletions

diff --git a/crawl-ref/source/uncancel.h b/crawl-ref/source/uncancel.h
new file mode 100644
index 0000000000..b5501e1a1d
--- /dev/null
+++ b/crawl-ref/source/uncancel.h
@@ -0,0 +1,19 @@
+/**
+ * @file
+ * @brief User interactions that need to be restarted if the game is forcibly
+ *        saved (via SIGHUP/window close).
+**/
+
+#ifndef UNCANCEL_H
+#define UNCANCEL_H
+
+void add_uncancel(uncancellable_type kind, int arg = 0);
+void run_uncancels();
+
+static inline void run_uncancel(uncancellable_type kind, int arg = 0)
+{
+    add_uncancel(kind, arg);
+    run_uncancels();
+}
+
+#endif