[PATCH v5 6/6] [gdb/cli] Simplify gdb_highlight_event_listener::notify

[Tom de Vries <tdevries@suse.de>]

Currently gdb_highlight_event_listener::notify does things more complicated
than necessary because of the unittest.

In more detail, the unit test cannot handle it if force_quit is called.

Fix this by making signal_handler_selftest capture force_quit.

This causes the question also to be asked for the SIGTERM case, so it leaves a
less attractive command line after terminating:
...
$ gdb -q a.out -ex "list"
Reading symbols from a.out...
$ ncel source styling using GNU source highlight of test.cpp? ([y] or n)
...

This patch currently makes gdb.gdb/unittest.exp fail:
...
FAIL: gdb.gdb/unittest.exp: no executable loaded: \
  maintenance selftest (got interactive prompt)
FAIL: gdb.gdb/unittest.exp: reversed initialization: \
  selftest not dependent on initialization order
FAIL: gdb.gdb/unittest.exp: executable loaded: \
  maintenance selftest (got interactive prompt)
...
because the testsuite triggers on the highlighting question.

Since this patch is an RFC at this point, I haven't invested time in addressing
this yet.

Tested on x86_64-linux.
---
 gdb/event-top.c    |  4 ++++
 gdb/source-cache.c | 29 +++++++++++------------------
 gdb/top.c          |  7 +++++++
 gdb/top.h          |  7 +++++++
 4 files changed, 29 insertions(+), 18 deletions(-)

diff --git a/gdb/event-top.c b/gdb/event-top.c
index 8c01c0902ea..b4b3fec5cdc 100644
--- a/gdb/event-top.c
+++ b/gdb/event-top.c
@@ -1235,6 +1235,8 @@ signal_handler_selftest::signal_handler_selftest ()
   m_saved_sigint_handler = signal (SIGINT, SIG_IGN);
   m_saved_sigterm_handler = signal (SIGTERM, SIG_IGN);
 
+  capture_quit_force = true;
+
   /* Only code from the selftest itself can cause the SIGINT or SIGTERM signal
      handlers to run.  */
   m_valid = true;
@@ -1242,6 +1244,8 @@ signal_handler_selftest::signal_handler_selftest ()
 
 signal_handler_selftest::~signal_handler_selftest ()
 {
+  capture_quit_force = false;
+
   /* Make sure that no pending SIGINT or SIGTERM escapes from the
      selftest.  */
   clear_pending_sigint ();
diff --git a/gdb/source-cache.c b/gdb/source-cache.c
index 6f514cbba3e..032a5d5b234 100644
--- a/gdb/source-cache.c
+++ b/gdb/source-cache.c
@@ -221,25 +221,18 @@ class gdb_highlight_event_listener : public srchilite::HighlightEventListener
 	return;
       }
 
-    /* If we got a SIGTERM, skip querying.  This isn't strictly
-       necessary as yquery runs a nested event loop for the secondary
-       prompt, which runs pending async signal handlers.  However,
-       this helps with the unit test, which makes sure that the quit
-       call at the bottom throws a gdb_exception_forced_quit exception
-       and that our caller doesn't swallow it.  Note we may receive a
-       SIGTERM in between the query and the quit call.  */
-    if (!sync_quit_force_run)
+    /* Ask the user what to do.  If we got a SIGTERM, don't skip querying.
+       Skipping isn't necessary as yquery runs a nested event loop for the
+       secondary prompt, which runs pending async signal handlers.  Note we
+       may receive a SIGTERM in between the query and the quit call.  */
+    int resp
+      = (yquery
+	 (_("Cancel source styling using GNU source highlight of %s? "),
+	  m_fullname.c_str ()));
+    if (!sync_quit_force_run && !resp)
       {
-	/* Ask the user what to do.  */
-	int resp
-	  = (yquery
-	     (_("Cancel source styling using GNU source highlight of %s? "),
-	      m_fullname.c_str ()));
-	if (!resp)
-	  {
-	    /* Continue highlighting.  */
-	    return;
-	  }
+	/* Continue highlighting.  */
+	return;
       }
 
     /* Interrupt highlighting.  Note we don't abort via the QUIT macro
diff --git a/gdb/top.c b/gdb/top.c
index 5028440b671..03b9ec5e1ae 100644
--- a/gdb/top.c
+++ b/gdb/top.c
@@ -1725,12 +1725,19 @@ undo_terminal_modifications_before_exit (void)
   current_ui = saved_top_level;
 }
 
+#if GDB_SELF_TEST
+bool capture_quit_force;
+#endif
 
 /* Quit without asking for confirmation.  */
 
 void
 quit_force (int *exit_arg, int from_tty)
 {
+#if GDB_SELF_TEST
+  if (capture_quit_force)
+    throw_forced_quit ("capture_quit_force");
+#endif
   int exit_code = 0;
 
   /* Clear the quit flag and sync_quit_force_run so that a
diff --git a/gdb/top.h b/gdb/top.h
index 47e16ca104e..d63396e6598 100644
--- a/gdb/top.h
+++ b/gdb/top.h
@@ -109,4 +109,11 @@ extern bool check_quiet_mode ();
 
 extern void unbuffer_stream (FILE *stream);
 
+#if GDB_SELF_TEST
+/* Rather than forcibly quitting when quit_force is called, note that it was
+   called by throwing a forced_quit.  This allows selftests to handle this
+   situation.  */
+extern bool capture_quit_force;
+#endif
+
 #endif
-- 
2.35.3