[PATCH v4 4/8] Python QUIT processing updates

[Kevin Buettner <kevinb@redhat.com>]

See the previous patches in this series for the motivation behind
these changes.

This commit contains updates to Python's QUIT handling.  Ideally, we'd
like to throw gdb_exception_forced_quit through the extension
language; I made an attempt to do this for gdb_exception_quit in an
earlier version of this patch, but Pedro pointed out that it is
(almost certainly) not safe to do so.

Still, we definitely don't want to swallow the exception representing
a SIGTERM for GDB, nor do we want to force modules written in the
extension language to have to explicitly handle this case.  Since the
idea is for GDB to cleanup and quit for this exception, we'll simply
call quit_force() just as if the gdb_exception_forced_quit propagation
had managed to make it back to the top level.

Bug: https://sourceware.org/bugzilla/show_bug.cgi?id=26761
---
 gdb/python/py-finishbreakpoint.c | 5 +++++
 gdb/python/py-gdb-readline.c     | 4 ++++
 gdb/python/py-symbol.c           | 5 +++++
 gdb/python/py-utils.c            | 3 +++
 gdb/python/py-value.c            | 5 +++++
 5 files changed, 22 insertions(+)

diff --git a/gdb/python/py-finishbreakpoint.c b/gdb/python/py-finishbreakpoint.c
index d4d129110e9..1a224b35779 100644
--- a/gdb/python/py-finishbreakpoint.c
+++ b/gdb/python/py-finishbreakpoint.c
@@ -20,6 +20,7 @@
 
 
 #include "defs.h"
+#include "top.h"		/* For quit_force().  */
 #include "python-internal.h"
 #include "breakpoint.h"
 #include "frame.h"
@@ -271,6 +272,10 @@ bpfinishpy_init (PyObject *self, PyObject *args, PyObject *kwargs)
 	    }
 	}
     }
+  catch (const gdb_exception_forced_quit &except)
+    {
+      quit_force (NULL, 0);
+    }
   catch (const gdb_exception &except)
     {
       /* Just swallow.  Either the return type or the function value
diff --git a/gdb/python/py-gdb-readline.c b/gdb/python/py-gdb-readline.c
index ea0f78c9ad8..b9294ad9afc 100644
--- a/gdb/python/py-gdb-readline.c
+++ b/gdb/python/py-gdb-readline.c
@@ -46,6 +46,10 @@ gdbpy_readline_wrapper (FILE *sys_stdin, FILE *sys_stdout,
       p = command_line_input (buffer, prompt, "python");
     }
   /* Handle errors by raising Python exceptions.  */
+  catch (const gdb_exception_forced_quit &e)
+    {
+      quit_force (NULL, 0);
+    }
   catch (const gdb_exception &except)
     {
       /* Detect user interrupt (Ctrl-C).  */
diff --git a/gdb/python/py-symbol.c b/gdb/python/py-symbol.c
index b8777966c47..899b0787582 100644
--- a/gdb/python/py-symbol.c
+++ b/gdb/python/py-symbol.c
@@ -18,6 +18,7 @@
    along with this program.  If not, see <http://www.gnu.org/licenses/>.  */
 
 #include "defs.h"
+#include "top.h"		/* For force_quit ().  */
 #include "block.h"
 #include "frame.h"
 #include "symtab.h"
@@ -515,6 +516,10 @@ 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_forced_quit &e)
+    {
+      quit_force (NULL, 0);
+    }
   catch (const gdb_exception &except)
     {
       /* Nothing.  */
diff --git a/gdb/python/py-utils.c b/gdb/python/py-utils.c
index 624b90a827f..d5b07a80d82 100644
--- a/gdb/python/py-utils.c
+++ b/gdb/python/py-utils.c
@@ -18,6 +18,7 @@
    along with this program.  If not, see <http://www.gnu.org/licenses/>.  */
 
 #include "defs.h"
+#include "top.h"		/* For quit_force ().  */
 #include "charset.h"
 #include "value.h"
 #include "python-internal.h"
@@ -219,6 +220,8 @@ gdbpy_convert_exception (const struct gdb_exception &exception)
 
   if (exception.reason == RETURN_QUIT)
     exc_class = PyExc_KeyboardInterrupt;
+  else if (exception.reason == RETURN_FORCED_QUIT)
+    quit_force (NULL, 0);
   else if (exception.error == MEMORY_ERROR)
     exc_class = gdbpy_gdb_memory_error;
   else
diff --git a/gdb/python/py-value.c b/gdb/python/py-value.c
index dcc92e51b60..9473468035b 100644
--- a/gdb/python/py-value.c
+++ b/gdb/python/py-value.c
@@ -18,6 +18,7 @@
    along with this program.  If not, see <http://www.gnu.org/licenses/>.  */
 
 #include "defs.h"
+#include "top.h"		/* For quit_force ().  */
 #include "charset.h"
 #include "value.h"
 #include "language.h"
@@ -371,6 +372,10 @@ 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_forced_quit &except)
+	{
+	  quit_force (NULL, 0);
+	}
       catch (const gdb_exception &except)
 	{
 	  val_obj->address = Py_None;
-- 
2.34.3