[PATCH v2 4/6] Python QUIT processing updates

[Kevin Buettner via Gdb-patches <gdb-patches@sourceware.org>]

See the previous patch in this series for the motivation behind these
updates.

This commit contains updates to Python's QUIT handling.  Specifically,
it makes sure that a SIGTERM sent to GDB will be propagated to the top
level.  While there are instances where we want to allow python code
to catch Ctrl-C / SIGINT (and possibly) swallow it, I don't think we
want that behavior for SIGTERM.  Therefore, there are cases where
sync_quit_force_run is checked explicitly.  In other cases, I
was able to defer the decision to GDB_PY_HANDLE_EXCEPTION.  (My goal
was to minimize explicit references to sync_quit_force_run.)
---
 gdb/python/py-finishbreakpoint.c |  6 ++++--
 gdb/python/py-gdb-readline.c     | 12 ++++++++----
 gdb/python/py-symbol.c           |  4 ++++
 gdb/python/py-utils.c            |  4 +++-
 gdb/python/py-value.c            |  4 ++++
 5 files changed, 23 insertions(+), 7 deletions(-)

diff --git a/gdb/python/py-finishbreakpoint.c b/gdb/python/py-finishbreakpoint.c
index 1d8373d807e..120e40db6eb 100644
--- a/gdb/python/py-finishbreakpoint.c
+++ b/gdb/python/py-finishbreakpoint.c
@@ -270,8 +270,10 @@ bpfinishpy_init (PyObject *self, PyObject *args, PyObject *kwargs)
     }
   catch (const gdb_exception &except)
     {
-      /* Just swallow.  Either the return type or the function value
-	 remain NULL.  */
+      /* Swallow everything except for a SIGTERM sent to GDB.  Either the
+         return type or the function value remain NULL.  */
+      if (sync_quit_force_run)
+	throw;
     }
 
   if (self_bpfinish->return_type == NULL || self_bpfinish->function_value == NULL)
diff --git a/gdb/python/py-gdb-readline.c b/gdb/python/py-gdb-readline.c
index 978c3a8b185..ba1dad931d2 100644
--- a/gdb/python/py-gdb-readline.c
+++ b/gdb/python/py-gdb-readline.c
@@ -45,12 +45,16 @@ gdbpy_readline_wrapper (FILE *sys_stdin, FILE *sys_stdout,
       p = command_line_input (prompt, "python");
     }
   /* Handle errors by raising Python exceptions.  */
+  catch (const gdb_exception_quit &except)
+    {
+      /* Propagate exception for SIGTERM.  */
+      if (sync_quit_force_run)
+        throw;
+      /* Otherwise, return for user interrupt (Ctrl-C).  */
+      return NULL;
+    }
   catch (const gdb_exception &except)
     {
-      /* Detect user interrupt (Ctrl-C).  */
-      if (except.reason == RETURN_QUIT)
-	return NULL;
-
       /* The thread state is nulled during gdbpy_readline_wrapper,
 	 with the original value saved in the following undocumented
 	 variable (see Python's Parser/myreadline.c and
diff --git a/gdb/python/py-symbol.c b/gdb/python/py-symbol.c
index d44b55ed5a9..89bddefaa1c 100644
--- a/gdb/python/py-symbol.c
+++ b/gdb/python/py-symbol.c
@@ -501,6 +501,10 @@ gdbpy_lookup_static_symbol (PyObject *self, PyObject *args, PyObject *kw)
 	= get_selected_frame (_("No frame selected."));
       block = get_frame_block (selected_frame, NULL);
     }
+  catch (const gdb_exception_quit &except)
+    {
+      GDB_PY_HANDLE_EXCEPTION (except);
+    }
   catch (const gdb_exception &except)
     {
       /* Nothing.  */
diff --git a/gdb/python/py-utils.c b/gdb/python/py-utils.c
index 10c4173efcd..d6d8cb82e96 100644
--- a/gdb/python/py-utils.c
+++ b/gdb/python/py-utils.c
@@ -233,7 +233,9 @@ gdbpy_convert_exception (const struct gdb_exception &exception)
 {
   PyObject *exc_class;
 
-  if (exception.reason == RETURN_QUIT)
+  if (sync_quit_force_run)
+    throw exception;
+  else if (exception.reason == RETURN_QUIT)
     exc_class = PyExc_KeyboardInterrupt;
   else if (exception.error == MEMORY_ERROR)
     exc_class = gdbpy_gdb_memory_error;
diff --git a/gdb/python/py-value.c b/gdb/python/py-value.c
index 8df8a15f8d6..cfc7a87d766 100644
--- a/gdb/python/py-value.c
+++ b/gdb/python/py-value.c
@@ -350,6 +350,10 @@ valpy_get_address (PyObject *self, void *closure)
 	  res_val = value_addr (val_obj->value);
 	  val_obj->address = value_to_value_object (res_val);
 	}
+      catch (const gdb_exception_quit &except)
+	{
+	  GDB_PY_HANDLE_EXCEPTION (except);
+	}
       catch (const gdb_exception &except)
 	{
 	  val_obj->address = Py_None;
-- 
2.31.1