From 9b9720149dfee4a9a961c29d0382fc5bdf9c975b Mon Sep 17 00:00:00 2001 From: Tom Tromey Date: Sat, 15 Oct 2016 09:20:02 -0600 Subject: Use unique_xmalloc_ptr in Python code This changes some utility functions in the Python code to return unique_xmalloc_ptr, and then fixes up the callers. I chose unique_xmalloc_ptr rather than std::string because at a few call points the xmalloc'd string is released and ownership transferred elsewhere. This patch found a few existing memory leaks. For example, py-unwind.c called gdbpy_obj_to_string but never freed the result. Built and regression tested on the buildbot. 2016-11-09 Tom Tromey * varobj.h (varobj_get_display_hint): Change return type. * varobj.c (varobj_get_display_hint): Return unique_xmalloc_ptr. (varobj_value_get_print_value): Update. * python/python.c (gdbpy_before_prompt_hook, gdbpy_print_stack) (gdbpy_apply_type_printers): Update. * python/python-internal.h (unicode_to_target_string) (python_string_to_target_string, python_string_to_host_string) (gdbpy_obj_to_string, gdbpy_exception_to_string) (gdbpy_get_display_hint): Change return types. * python/py-varobj.c (py_varobj_iter_next): Update. * python/py-value.c (valpy_getitem, convert_value_from_python): Update. * python/py-utils.c (unicode_to_encoded_string) (unicode_to_target_string, python_string_to_target_string) (python_string_to_host_string, gdbpy_obj_to_string) (gdbpy_exception_to_string): Return unique_xmalloc_ptr. * python/py-unwind.c (pyuw_parse_register_id): Update. * python/py-type.c (typy_getitem): Update. * python/py-prettyprint.c (gdbpy_get_display_hint) (print_stack_unless_memory_error, print_children) (gdbpy_apply_val_pretty_printer): Update. * python/py-param.c (set_parameter_value): Update. (get_doc_string, call_doc_function): Return unique_xmalloc_ptr. (get_set_value, get_show_value, compute_enum_values, parmpy_init): Update. * python/py-infthread.c (thpy_set_name): Update. * python/py-function.c (fnpy_call, fnpy_init): Update. * python/py-framefilter.c (extract_sym): Change "name" to unique_xmalloc_ptr. (enumerate_args, enumerate_locals): Update. (py_print_frame): Use unique_xmalloc_ptr. * python/py-frame.c (frapy_read_var): Update. Remove cleanup. * python/py-cmd.c (cmdpy_function, cmdpy_completer, cmdpy_init): Update. * python/py-breakpoint.c (bppy_set_condition): Use unique_xmalloc_ptr. (bppy_init): Likewise. Remove cleanup. (local_setattro): Update. * mi/mi-cmd-var.c (print_varobj, mi_cmd_var_list_children) (varobj_update_one): Update. --- gdb/python/py-param.c | 46 ++++++++++++++++++++-------------------------- 1 file changed, 20 insertions(+), 26 deletions(-) (limited to 'gdb/python/py-param.c') diff --git a/gdb/python/py-param.c b/gdb/python/py-param.c index 3604f9f..0d19c97 100644 --- a/gdb/python/py-param.c +++ b/gdb/python/py-param.c @@ -148,21 +148,19 @@ set_parameter_value (parmpy_object *self, PyObject *value) } else { - char *string; - - string = python_string_to_host_string (value); + gdb::unique_xmalloc_ptr + string (python_string_to_host_string (value)); if (string == NULL) return -1; xfree (self->value.stringval); - self->value.stringval = string; + self->value.stringval = string.release (); } break; case var_enum: { int i; - char *str; if (! gdbpy_is_string (value)) { @@ -171,13 +169,13 @@ set_parameter_value (parmpy_object *self, PyObject *value) return -1; } - str = python_string_to_host_string (value); + gdb::unique_xmalloc_ptr + str (python_string_to_host_string (value)); if (str == NULL) return -1; for (i = 0; self->enumeration[i]; ++i) - if (! strcmp (self->enumeration[i], str)) + if (! strcmp (self->enumeration[i], str.get ())) break; - xfree (str); if (! self->enumeration[i]) { PyErr_SetString (PyExc_RuntimeError, @@ -301,10 +299,10 @@ set_attr (PyObject *obj, PyObject *attr_name, PyObject *val) /* A helper function which returns a documentation string for an object. */ -static char * +static gdb::unique_xmalloc_ptr get_doc_string (PyObject *object, PyObject *attr) { - char *result = NULL; + gdb::unique_xmalloc_ptr result; if (PyObject_HasAttr (object, attr)) { @@ -319,7 +317,7 @@ get_doc_string (PyObject *object, PyObject *attr) Py_XDECREF (ds_obj); } if (! result) - result = xstrdup (_("This command is not documented.")); + result.reset (xstrdup (_("This command is not documented."))); return result; } @@ -327,10 +325,10 @@ get_doc_string (PyObject *object, PyObject *attr) argument ARG. ARG can be NULL. METHOD should return a Python string. If this function returns NULL, there has been an error and the appropriate exception set. */ -static char * +static gdb::unique_xmalloc_ptr call_doc_function (PyObject *obj, PyObject *method, PyObject *arg) { - char *data = NULL; + gdb::unique_xmalloc_ptr data; PyObject *result = PyObject_CallMethodObjArgs (obj, method, arg, NULL); if (! result) @@ -365,7 +363,7 @@ get_set_value (char *args, int from_tty, struct cmd_list_element *c) { PyObject *obj = (PyObject *) get_cmd_context (c); - char *set_doc_string; + gdb::unique_xmalloc_ptr set_doc_string; struct cleanup *cleanup = ensure_python_env (get_current_arch (), current_language); PyObject *set_doc_func = PyString_FromString ("get_set_string"); @@ -387,8 +385,7 @@ get_set_value (char *args, int from_tty, set_doc_string = get_doc_string (obj, set_doc_cst); } - make_cleanup (xfree, set_doc_string); - fprintf_filtered (gdb_stdout, "%s\n", set_doc_string); + fprintf_filtered (gdb_stdout, "%s\n", set_doc_string.get ()); Py_XDECREF (set_doc_func); do_cleanups (cleanup); @@ -413,7 +410,7 @@ get_show_value (struct ui_file *file, int from_tty, const char *value) { PyObject *obj = (PyObject *) get_cmd_context (c); - char *show_doc_string = NULL; + gdb::unique_xmalloc_ptr show_doc_string; struct cleanup *cleanup = ensure_python_env (get_current_arch (), current_language); PyObject *show_doc_func = PyString_FromString ("get_show_string"); @@ -433,9 +430,7 @@ get_show_value (struct ui_file *file, int from_tty, if (! show_doc_string) goto error; - make_cleanup (xfree, show_doc_string); - - fprintf_filtered (file, "%s\n", show_doc_string); + fprintf_filtered (file, "%s\n", show_doc_string.get ()); } else { @@ -443,8 +438,7 @@ get_show_value (struct ui_file *file, int from_tty, callback function does not exist, then attempt to read the show_doc attribute. */ show_doc_string = get_doc_string (obj, show_doc_cst); - make_cleanup (xfree, show_doc_string); - fprintf_filtered (file, "%s %s\n", show_doc_string, value); + fprintf_filtered (file, "%s %s\n", show_doc_string.get (), value); } Py_XDECREF (show_doc_func); @@ -614,7 +608,7 @@ compute_enum_values (parmpy_object *self, PyObject *enum_values) _("The enumeration item not a string.")); return 0; } - self->enumeration[i] = python_string_to_host_string (item); + self->enumeration[i] = python_string_to_host_string (item).release (); Py_DECREF (item); if (self->enumeration[i] == NULL) { @@ -716,9 +710,9 @@ parmpy_init (PyObject *self, PyObject *args, PyObject *kwds) if (! cmd_name) return -1; - set_doc = get_doc_string (self, set_doc_cst); - show_doc = get_doc_string (self, show_doc_cst); - doc = get_doc_string (self, gdbpy_doc_cst); + set_doc = get_doc_string (self, set_doc_cst).release (); + show_doc = get_doc_string (self, show_doc_cst).release (); + doc = get_doc_string (self, gdbpy_doc_cst).release (); Py_INCREF (self); -- cgit v1.1