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[PATCH 3/6] framefilter quit: Code cleanup: Avoid gotos
- From: Jan Kratochvil <jan dot kratochvil at redhat dot com>
- To: gdb-patches at sourceware dot org
- Cc: Phil Muldoon <pmuldoon at redhat dot com>
- Date: Sat, 07 Feb 2015 15:45:24 +0100
- Subject: [PATCH 3/6] framefilter quit: Code cleanup: Avoid gotos
- Authentication-results: sourceware.org; auth=none
- References: <20150207144501 dot 14897 dot 90709 dot stgit at host1 dot jankratochvil dot net>
Hi,
goto error patters are sometimes AFAIK used in C for the cases like:
int retval=-1;
if (!(a=malloc())) goto error;
if (!(b=malloc())) goto error_a;
if (!(c=malloc())) goto error_b;
retval=0;
error_c: free(c);
error_b: free(b);
error_a: free(a);
error: return retval;
But here there is single error label with one do_cleanups() which I do not find
it worth the goto complication. Without goto one can then furher merge code in
the exit paths in the next patches and ... after all it is all the same, just
without a goto.
Jan
gdb/ChangeLog
2015-02-06 Jan Kratochvil <jan.kratochvil@redhat.com>
* python/py-framefilter.c (py_print_frame): Substitute goto error.
Remove the error label.
---
gdb/python/py-framefilter.c | 103 +++++++++++++++++++++++++++++++------------
1 file changed, 74 insertions(+), 29 deletions(-)
diff --git a/gdb/python/py-framefilter.c b/gdb/python/py-framefilter.c
index 896e2a8..ba1b237 100644
--- a/gdb/python/py-framefilter.c
+++ b/gdb/python/py-framefilter.c
@@ -1033,14 +1033,20 @@ py_print_frame (PyObject *filter, int flags,
read them if they returned filter object requires us to do so. */
py_inf_frame = PyObject_CallMethod (filter, "inferior_frame", NULL);
if (py_inf_frame == NULL)
- goto error;
+ {
+ do_cleanups (cleanup_stack);
+ return EXT_LANG_BT_ERROR;
+ }
frame = frame_object_to_frame_info (py_inf_frame);;
Py_DECREF (py_inf_frame);
if (frame == NULL)
- goto error;
+ {
+ do_cleanups (cleanup_stack);
+ return EXT_LANG_BT_ERROR;
+ }
TRY_CATCH (except, RETURN_MASK_ALL)
{
@@ -1049,7 +1055,8 @@ py_print_frame (PyObject *filter, int flags,
if (except.reason < 0)
{
gdbpy_convert_exception (except);
- goto error;
+ do_cleanups (cleanup_stack);
+ return EXT_LANG_BT_ERROR;
}
/* stack-list-variables. */
@@ -1057,7 +1064,10 @@ py_print_frame (PyObject *filter, int flags,
{
if (py_mi_print_variables (filter, out, &opts,
args_type, frame) == EXT_LANG_BT_ERROR)
- goto error;
+ {
+ do_cleanups (cleanup_stack);
+ return EXT_LANG_BT_ERROR;
+ }
do_cleanups (cleanup_stack);
return EXT_LANG_BT_COMPLETED;
}
@@ -1080,7 +1090,8 @@ py_print_frame (PyObject *filter, int flags,
if (except.reason < 0)
{
gdbpy_convert_exception (except);
- goto error;
+ do_cleanups (cleanup_stack);
+ return EXT_LANG_BT_ERROR;
}
}
@@ -1091,7 +1102,10 @@ py_print_frame (PyObject *filter, int flags,
PyObject *paddr = PyObject_CallMethod (filter, "address", NULL);
if (paddr == NULL)
- goto error;
+ {
+ do_cleanups (cleanup_stack);
+ return EXT_LANG_BT_ERROR;
+ }
if (paddr != Py_None)
{
@@ -1135,7 +1149,8 @@ py_print_frame (PyObject *filter, int flags,
if (except.reason < 0)
{
gdbpy_convert_exception (except);
- goto error;
+ do_cleanups (cleanup_stack);
+ return EXT_LANG_BT_ERROR;
}
}
@@ -1155,7 +1170,8 @@ py_print_frame (PyObject *filter, int flags,
if (except.reason < 0)
{
gdbpy_convert_exception (except);
- goto error;
+ do_cleanups (cleanup_stack);
+ return EXT_LANG_BT_ERROR;
}
}
@@ -1166,7 +1182,10 @@ py_print_frame (PyObject *filter, int flags,
const char *function = NULL;
if (py_func == NULL)
- goto error;
+ {
+ do_cleanups (cleanup_stack);
+ return EXT_LANG_BT_ERROR;
+ }
if (gdbpy_is_string (py_func))
{
@@ -1178,7 +1197,8 @@ py_print_frame (PyObject *filter, int flags,
if (function == NULL)
{
Py_DECREF (py_func);
- goto error;
+ do_cleanups (cleanup_stack);
+ return EXT_LANG_BT_ERROR;
}
make_cleanup (xfree, function_to_free);
}
@@ -1188,7 +1208,10 @@ py_print_frame (PyObject *filter, int flags,
struct bound_minimal_symbol msymbol;
if (PyErr_Occurred ())
- goto error;
+ {
+ do_cleanups (cleanup_stack);
+ return EXT_LANG_BT_ERROR;
+ }
msymbol = lookup_minimal_symbol_by_pc (addr);
if (msymbol.minsym != NULL)
@@ -1200,7 +1223,8 @@ py_print_frame (PyObject *filter, int flags,
_("FrameDecorator.function: expecting a " \
"String, integer or None."));
Py_DECREF (py_func);
- goto error;
+ do_cleanups (cleanup_stack);
+ return EXT_LANG_BT_ERROR;
}
TRY_CATCH (except, RETURN_MASK_ALL)
@@ -1215,7 +1239,8 @@ py_print_frame (PyObject *filter, int flags,
{
Py_DECREF (py_func);
gdbpy_convert_exception (except);
- goto error;
+ do_cleanups (cleanup_stack);
+ return EXT_LANG_BT_ERROR;
}
Py_DECREF (py_func);
}
@@ -1227,7 +1252,10 @@ py_print_frame (PyObject *filter, int flags,
if (print_args)
{
if (py_print_args (filter, out, args_type, frame) == EXT_LANG_BT_ERROR)
- goto error;
+ {
+ do_cleanups (cleanup_stack);
+ return EXT_LANG_BT_ERROR;
+ }
}
/* File name/source/line number information. */
@@ -1240,7 +1268,8 @@ py_print_frame (PyObject *filter, int flags,
if (except.reason < 0)
{
gdbpy_convert_exception (except);
- goto error;
+ do_cleanups (cleanup_stack);
+ return EXT_LANG_BT_ERROR;
}
if (PyObject_HasAttrString (filter, "filename"))
@@ -1248,7 +1277,10 @@ py_print_frame (PyObject *filter, int flags,
PyObject *py_fn = PyObject_CallMethod (filter, "filename", NULL);
if (py_fn == NULL)
- goto error;
+ {
+ do_cleanups (cleanup_stack);
+ return EXT_LANG_BT_ERROR;
+ }
if (py_fn != Py_None)
{
@@ -1257,7 +1289,8 @@ py_print_frame (PyObject *filter, int flags,
if (filename == NULL)
{
Py_DECREF (py_fn);
- goto error;
+ do_cleanups (cleanup_stack);
+ return EXT_LANG_BT_ERROR;
}
make_cleanup (xfree, filename);
@@ -1273,7 +1306,8 @@ py_print_frame (PyObject *filter, int flags,
{
Py_DECREF (py_fn);
gdbpy_convert_exception (except);
- goto error;
+ do_cleanups (cleanup_stack);
+ return EXT_LANG_BT_ERROR;
}
}
Py_DECREF (py_fn);
@@ -1285,7 +1319,10 @@ py_print_frame (PyObject *filter, int flags,
int line;
if (py_line == NULL)
- goto error;
+ {
+ do_cleanups (cleanup_stack);
+ return EXT_LANG_BT_ERROR;
+ }
if (py_line != Py_None)
{
@@ -1300,7 +1337,8 @@ py_print_frame (PyObject *filter, int flags,
{
Py_DECREF (py_line);
gdbpy_convert_exception (except);
- goto error;
+ do_cleanups (cleanup_stack);
+ return EXT_LANG_BT_ERROR;
}
}
Py_DECREF (py_line);
@@ -1319,7 +1357,8 @@ py_print_frame (PyObject *filter, int flags,
if (except.reason < 0)
{
gdbpy_convert_exception (except);
- goto error;
+ do_cleanups (cleanup_stack);
+ return EXT_LANG_BT_ERROR;
}
}
@@ -1327,7 +1366,10 @@ py_print_frame (PyObject *filter, int flags,
{
if (py_print_locals (filter, out, args_type, indent,
frame) == EXT_LANG_BT_ERROR)
- goto error;
+ {
+ do_cleanups (cleanup_stack);
+ return EXT_LANG_BT_ERROR;
+ }
}
{
@@ -1336,7 +1378,10 @@ py_print_frame (PyObject *filter, int flags,
/* Finally recursively print elided frames, if any. */
elided = get_py_iter_from_func (filter, "elided");
if (elided == NULL)
- goto error;
+ {
+ do_cleanups (cleanup_stack);
+ return EXT_LANG_BT_ERROR;
+ }
make_cleanup_py_decref (elided);
if (elided != Py_None)
@@ -1358,23 +1403,23 @@ py_print_frame (PyObject *filter, int flags,
if (success == EXT_LANG_BT_ERROR)
{
Py_DECREF (item);
- goto error;
+ do_cleanups (cleanup_stack);
+ return EXT_LANG_BT_ERROR;
}
Py_DECREF (item);
}
if (item == NULL && PyErr_Occurred ())
- goto error;
+ {
+ do_cleanups (cleanup_stack);
+ return EXT_LANG_BT_ERROR;
+ }
}
}
do_cleanups (cleanup_stack);
return EXT_LANG_BT_COMPLETED;
-
- error:
- do_cleanups (cleanup_stack);
- return EXT_LANG_BT_ERROR;
}
/* Helper function to initiate frame filter invocation at starting