Use a wrapper for PyErr_Fetch

This introduces a new class that wraps PyErr_Fetch and PyErr_Restore,
and then changes all the callers in gdb to use it.  This reduces the
amount of explicit reference counting that is done in the Python code.
I also found and fixed a latent bug in gdbpy_print_stack -- it was not
correctly checking some error conditions, nor clearing the exception
when needed.

gdb/ChangeLog
2019-01-03  Tom Tromey  <tom@tromey.com>

	* python/python.c (gdbpy_enter, ~gdbpy_enter): Update.
	(gdbpy_print_stack): Use gdbpy_err_fetch.
	* python/python-internal.h (class gdbpy_err_fetch): New class.
	(class gdbpy_enter) <m_error_type, m_error_value,
	m_error_traceback>: Remove.
	<m_error>: New member.
	(gdbpy_exception_to_string): Don't declare.
	* python/py-varobj.c (py_varobj_iter_next): Use gdbpy_err_fetch.
	* python/py-value.c (convert_value_from_python): Use
	gdbpy_err_fetch.
	* python/py-utils.c (gdbpy_err_fetch::to_string): Rename from
	gdbpy_exception_to_string.
	(gdbpy_handle_exception): Use gdbpy_err_fetch.
	* python/py-prettyprint.c (print_stack_unless_memory_error): Use
	gdbpy_err_fetch.
This commit is contained in:
Tom Tromey 2018-12-27 11:32:01 -07:00
parent 169bb27bce
commit 5c329e6ab4
7 changed files with 121 additions and 73 deletions

View file

@ -70,14 +70,8 @@ py_varobj_iter_next (struct varobj_iter *self)
/* If we got a memory error, just use the text as the item. */
if (PyErr_ExceptionMatches (gdbpy_gdb_memory_error))
{
PyObject *type, *value, *trace;
PyErr_Fetch (&type, &value, &trace);
gdb::unique_xmalloc_ptr<char>
value_str (gdbpy_exception_to_string (type, value));
Py_XDECREF (type);
Py_XDECREF (value);
Py_XDECREF (trace);
gdbpy_err_fetch fetched_error;
gdb::unique_xmalloc_ptr<char> value_str = fetched_error.to_string ();
if (value_str == NULL)
{
gdbpy_print_stack ();