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-utils.c | 60 ++++++++++++++++++++++----------------------------- 1 file changed, 26 insertions(+), 34 deletions(-) (limited to 'gdb/python/py-utils.c') diff --git a/gdb/python/py-utils.c b/gdb/python/py-utils.c index 2e2121d..9f99e29 100644 --- a/gdb/python/py-utils.c +++ b/gdb/python/py-utils.c @@ -107,10 +107,10 @@ python_string_to_unicode (PyObject *obj) conversion, NULL will be returned and a python exception will be set. The caller is responsible for xfree'ing the string. */ -static char * +static gdb::unique_xmalloc_ptr unicode_to_encoded_string (PyObject *unicode_str, const char *charset) { - char *result; + gdb::unique_xmalloc_ptr result; PyObject *string; /* Translate string to named charset. */ @@ -119,9 +119,9 @@ unicode_to_encoded_string (PyObject *unicode_str, const char *charset) return NULL; #ifdef IS_PY3K - result = xstrdup (PyBytes_AsString (string)); + result.reset (xstrdup (PyBytes_AsString (string))); #else - result = xstrdup (PyString_AsString (string)); + result.reset (xstrdup (PyString_AsString (string))); #endif Py_DECREF (string); @@ -140,12 +140,11 @@ unicode_to_encoded_python_string (PyObject *unicode_str, const char *charset) return PyUnicode_AsEncodedString (unicode_str, charset, NULL); } -/* Returns a newly allocated string with the contents of the given unicode - string object converted to the target's charset. If an error occurs during - the conversion, NULL will be returned and a python exception will be set. - - The caller is responsible for xfree'ing the string. */ -char * +/* Returns a newly allocated string with the contents of the given + unicode string object converted to the target's charset. If an + error occurs during the conversion, NULL will be returned and a + python exception will be set. */ +gdb::unique_xmalloc_ptr unicode_to_target_string (PyObject *unicode_str) { return unicode_to_encoded_string (unicode_str, @@ -164,20 +163,18 @@ unicode_to_target_python_string (PyObject *unicode_str) } /* Converts a python string (8-bit or unicode) to a target string in - the target's charset. Returns NULL on error, with a python exception set. - - The caller is responsible for xfree'ing the string. */ -char * + the target's charset. Returns NULL on error, with a python + exception set. */ +gdb::unique_xmalloc_ptr python_string_to_target_string (PyObject *obj) { PyObject *str; - char *result; str = python_string_to_unicode (obj); if (str == NULL) return NULL; - result = unicode_to_target_string (str); + gdb::unique_xmalloc_ptr result (unicode_to_target_string (str)); Py_DECREF (str); return result; } @@ -203,20 +200,19 @@ python_string_to_target_python_string (PyObject *obj) } /* Converts a python string (8-bit or unicode) to a target string in - the host's charset. Returns NULL on error, with a python exception set. - - The caller is responsible for xfree'ing the string. */ -char * + the host's charset. Returns NULL on error, with a python exception + set. */ +gdb::unique_xmalloc_ptr python_string_to_host_string (PyObject *obj) { PyObject *str; - char *result; str = python_string_to_unicode (obj); if (str == NULL) return NULL; - result = unicode_to_encoded_string (str, host_charset ()); + gdb::unique_xmalloc_ptr + result (unicode_to_encoded_string (str, host_charset ())); Py_DECREF (str); return result; } @@ -243,20 +239,21 @@ gdbpy_is_string (PyObject *obj) } /* Return the string representation of OBJ, i.e., str (obj). - Space for the result is malloc'd, the caller must free. If the result is NULL a python error occurred, the caller must clear it. */ -char * +gdb::unique_xmalloc_ptr gdbpy_obj_to_string (PyObject *obj) { PyObject *str_obj = PyObject_Str (obj); if (str_obj != NULL) { + gdb::unique_xmalloc_ptr msg; + #ifdef IS_PY3K - char *msg = python_string_to_host_string (str_obj); + msg = python_string_to_host_string (str_obj); #else - char *msg = xstrdup (PyString_AsString (str_obj)); + msg.reset (xstrdup (PyString_AsString (str_obj))); #endif Py_DECREF (str_obj); @@ -269,14 +266,11 @@ gdbpy_obj_to_string (PyObject *obj) /* Return the string representation of the exception represented by TYPE, VALUE which is assumed to have been obtained with PyErr_Fetch, i.e., the error indicator is currently clear. - Space for the result is malloc'd, the caller must free. If the result is NULL a python error occurred, the caller must clear it. */ -char * +gdb::unique_xmalloc_ptr gdbpy_exception_to_string (PyObject *ptype, PyObject *pvalue) { - char *str; - /* There are a few cases to consider. For example: pvalue is a string when PyErr_SetString is used. @@ -288,11 +282,9 @@ gdbpy_exception_to_string (PyObject *ptype, PyObject *pvalue) gdb.GdbError ("message"). */ if (pvalue && pvalue != Py_None) - str = gdbpy_obj_to_string (pvalue); + return gdbpy_obj_to_string (pvalue); else - str = gdbpy_obj_to_string (ptype); - - return str; + return gdbpy_obj_to_string (ptype); } /* Convert a GDB exception to the appropriate Python exception. -- cgit v1.1