[patch][python] Fix sigsegv when a printer fails to return a value and string_print is set.
http://sourceware.org/ml/gdb-patches/2011-07/msg00719.html
http://sourceware.org/ml/gdb-cvs/2011-07/msg00234.html
### src/gdb/ChangeLog 2011/07/27 19:31:30 1.13236
### src/gdb/ChangeLog 2011/07/28 10:36:37 1.13237
## -1,3 +1,8 @@
+2011-07-28 Phil Muldoon <pmuldoon@redhat.com>
+
+ * varobj.c (value_get_print_value): Move hint check later into the
+ function. Comment function. Free thevalue before reusing it.
+
2011-07-27 Jan Kratochvil <jan.kratochvil@redhat.com>
Pedro Alves <pedro@codesourcery.com>
--- src/gdb/varobj.c 2011/07/18 09:21:43 1.180
+++ src/gdb/varobj.c 2011/07/28 10:36:40 1.181
@@ -2610,25 +2610,21 @@
if (PyObject_HasAttr (value_formatter, gdbpy_to_string_cst))
{
- char *hint;
struct value *replacement;
PyObject *output = NULL;
- hint = gdbpy_get_display_hint (value_formatter);
- if (hint)
- {
- if (!strcmp (hint, "string"))
- string_print = 1;
- xfree (hint);
- }
-
output = apply_varobj_pretty_printer (value_formatter,
&replacement,
stb);
+
+ /* If we have string like output ... */
if (output)
{
make_cleanup_py_decref (output);
+ /* If this is a lazy string, extract it. For lazy
+ strings we always print as a string, so set
+ string_print. */
if (gdbpy_is_lazy_string (output))
{
gdbpy_extract_lazy_string (output, &str_addr, &type,
@@ -2638,12 +2634,27 @@
}
else
{
+ /* If it is a regular (non-lazy) string, extract
+ it and copy the contents into THEVALUE. If the
+ hint says to print it as a string, set
+ string_print. Otherwise just return the extracted
+ string as a value. */
+
PyObject *py_str
= python_string_to_target_python_string (output);
if (py_str)
{
char *s = PyString_AsString (py_str);
+ char *hint;
+
+ hint = gdbpy_get_display_hint (value_formatter);
+ if (hint)
+ {
+ if (!strcmp (hint, "string"))
+ string_print = 1;
+ xfree (hint);
+ }
len = PyString_Size (py_str);
thevalue = xmemdup (s, len + 1, len + 1);
@@ -2662,6 +2673,9 @@
gdbpy_print_stack ();
}
}
+ /* If the printer returned a replacement value, set VALUE
+ to REPLACEMENT. If there is not a replacement value,
+ just use the value passed to this function. */
if (replacement)
value = replacement;
}
@@ -2672,12 +2686,18 @@
get_formatted_print_options (&opts, format_code[(int) format]);
opts.deref_ref = 0;
opts.raw = 1;
+
+ /* If the THEVALUE has contents, it is a regular string. */
if (thevalue)
LA_PRINT_STRING (stb, type, thevalue, len, encoding, 0, &opts);
else if (string_print)
+ /* Otherwise, if string_print is set, and it is not a regular
+ string, it is a lazy string. */
val_print_string (type, encoding, str_addr, len, stb, &opts);
else
+ /* All other cases. */
common_val_print (value, stb, 0, &opts, current_language);
+
thevalue = ui_file_xstrdup (stb, NULL);
do_cleanups (old_chain);
### src/gdb/testsuite/ChangeLog 2011/07/27 21:18:39 1.2816
### src/gdb/testsuite/ChangeLog 2011/07/28 10:36:40 1.2817
## -1,3 +1,10 @@
+2011-07-28 Phil Muldoon <pmuldoon@redhat.com>
+
+ * gdb.python/py-mi.exp: Test printers returning string hint, and
+ also not returning a value.
+ * gdb.python/py-prettyprint.c: Add testcase for above.
+ * gdb.python/py-prettyprint.py: Add test printer for above.
+
2011-07-27 Jan Kratochvil <jan.kratochvil@redhat.com>
* gdb.dwarf2/dw2-simple-locdesc.S: Change DWARF version to 3.
--- src/gdb/testsuite/gdb.python/py-mi.exp 2011/07/26 18:38:55 1.13
+++ src/gdb/testsuite/gdb.python/py-mi.exp 2011/07/28 10:36:40 1.14
@@ -284,6 +284,13 @@ mi_list_varobj_children nstype2 {
{ {nstype2.<error at 0>} {<error at 0>} 6 {char \[6\]} }
} "list children after setting exception flag"
+mi_create_varobj me me \
+ "create me varobj"
+
+mi_gdb_test "-var-evaluate-expression me" \
+ "\\^done,value=\"<error reading variable: Cannot access memory.>.*\"" \
+ "evaluate me varobj"
+
# C++ MI tests
gdb_exit
if { [gdb_compile "${srcdir}/${subdir}/${srcfile}" "${binfile}" \
--- src/gdb/testsuite/gdb.python/py-prettyprint.c 2011/04/29 12:45:46 1.12
+++ src/gdb/testsuite/gdb.python/py-prettyprint.c 2011/07/28 10:36:40 1.13
@@ -149,6 +149,11 @@
typedef struct justchildren nostring_type;
+struct memory_error
+{
+ const char *s;
+};
+
struct container
{
string name;
@@ -227,6 +232,7 @@
/* Clearing by being `static' could invoke an other GDB C++ bug. */
struct nullstr nullstr;
nostring_type nstype, nstype2;
+ struct memory_error me;
struct ns ns, ns2;
struct lazystring estring, estring2;
struct hint_error hint_error;
@@ -234,6 +240,8 @@
nstype.elements = narray;
nstype.len = 0;
+ me.s = "blah";
+
init_ss(&ss, 1, 2);
init_ss(ssa+0, 3, 4);
init_ss(ssa+1, 5, 6);
--- src/gdb/testsuite/gdb.python/py-prettyprint.py 2011/04/11 17:40:41 1.11
+++ src/gdb/testsuite/gdb.python/py-prettyprint.py 2011/07/28 10:36:40 1.12
@@ -17,6 +17,7 @@
# printers.
import re
+import gdb
# Test returning a Value from a printer.
class string_print:
@@ -186,6 +187,18 @@
yield 's', self.val['s']
yield 'x', self.val['x']
+class MemoryErrorString:
+ "Raise an error"
+
+ def __init__(self, val):
+ self.val = val
+
+ def to_string(self):
+ raise gdb.MemoryError ("Cannot access memory.");
+
+ def display_hint (self):
+ return 'string'
+
def lookup_function (val):
"Look-up and return a pretty-printer that can print val."
@@ -261,6 +274,8 @@
pretty_printers_dict[re.compile ('^struct hint_error$')] = pp_hint_error
pretty_printers_dict[re.compile ('^hint_error$')] = pp_hint_error
+ pretty_printers_dict[re.compile ('^memory_error$')] = MemoryErrorString
+
pretty_printers_dict = {}
register_pretty_printers ()