+2016-08-24 Kevin Buettner <kevinb@redhat.com>
+
+ * gdb.python/py-recurse-unwind.c: New file.
+ * gdb.python/py-recurse-unwind.py: New file.
+ * gdb.python/py-recurse-unwind.exp: New file.
+
2016-08-24 Simon Marchi <simon.marchi@ericsson.com>
* gdb.base/set-inferior-tty.exp: New file.
--- /dev/null
+/* This test program is part of GDB, the GNU debugger.
+
+ Copyright 2016 Free Software Foundation, Inc.
+
+ This program is free software; you can redistribute it and/or modify
+ it under the terms of the GNU General Public License as published by
+ the Free Software Foundation; either version 3 of the License, or
+ (at your option) any later version.
+
+ This program is distributed in the hope that it will be useful,
+ but WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ GNU General Public License for more details.
+
+ You should have received a copy of the GNU General Public License
+ along with this program. If not, see <http://www.gnu.org/licenses/>. */
+
+/* This is the test program loaded into GDB by the py-recurse-unwind test. */
+
+void
+ccc (int arg)
+{
+}
+
+void
+bbb (int arg)
+{
+ ccc (789);
+}
+
+void
+aaa (int arg)
+{
+ bbb (456);
+}
+
+int
+main ()
+{
+ aaa (123);
+ return 0;
+}
--- /dev/null
+# Copyright (C) 2016 Free Software Foundation, Inc.
+
+# This program is free software; you can redistribute it and/or modify
+# it under the terms of the GNU General Public License as published by
+# the Free Software Foundation; either version 3 of the License, or
+# (at your option) any later version.
+#
+# This program is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+# GNU General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License
+# along with this program. If not, see <http://www.gnu.org/licenses/>.
+
+# This file is part of the GDB testsuite. It is used to verify that
+# GDB does not recurse infinitely when calling gdb.parse_and_eval() in
+# the course of sniffing a frame in a Python unwinder.
+
+# The unwinder has been constructed so that, should recursion occur,
+# it will be detected in the unwinder so that we won't need to wait
+# for a timeout.
+
+
+load_lib gdb-python.exp
+
+standard_testfile
+
+if { [prepare_for_testing ${testfile}.exp ${testfile} ${srcfile}] } {
+ return -1
+}
+
+# Skip all tests if Python scripting is not enabled.
+if { [skip_python_tests] } { continue }
+
+set pyfile [gdb_remote_download host ${srcdir}/${subdir}/${testfile}.py]
+
+gdb_test "source ${pyfile}" "Python script imported" \
+ "import python scripts"
+
+# The following tests require execution.
+
+if ![runto_main] then {
+ fail "Can't run to main"
+ return 0
+}
+
+gdb_breakpoint "ccc"
+
+gdb_continue_to_breakpoint "ccc"
+
+# If the unwinder is active, the usage count will increment while
+# running to the breakpoint. Reset it prior to doing the backtrace.
+gdb_test_no_output "python TestUnwinder.reset_count()"
+
+# The python based unwinder should be called a number of times while
+# generating the backtrace, but its sniffer always returns None. So
+# it doesn't really contribute to generating any of the frames below.
+#
+# But that's okay. Our goal here is to make sure that GDB doesn't
+# get hung up in potentially infinite recursion when invoking the
+# Python-based unwinder.
+
+setup_kfail "gdb/19927" "*-*-*"
+gdb_test_sequence "bt" "backtrace" {
+ "\\r\\n#0 .* ccc \\(arg=789\\) at "
+ "\\r\\n#1 .* bbb \\(arg=456\\) at "
+ "\\r\\n#2 .* aaa \\(arg=123\\) at "
+ "\\r\\n#3 .* main \\(.*\\) at"
+}
+
+# Test that the python-based unwinder / sniffer was actually called
+# during generation of the backtrace.
+setup_kfail "gdb/19927" "*-*-*"
+gdb_test "python print(TestUnwinder.count > 0)" "True"
--- /dev/null
+# Copyright (C) 2016 Free Software Foundation, Inc.
+
+# This program is free software; you can redistribute it and/or modify
+# it under the terms of the GNU General Public License as published by
+# the Free Software Foundation; either version 3 of the License, or
+# (at your option) any later version.
+#
+# This program is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+# GNU General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License
+# along with this program. If not, see <http://www.gnu.org/licenses/>.
+
+# This unwinder never does any unwinding. It'll (pretend to) "sniff"
+# the frame and ultimately return None, indicating that actual unwinding
+# should be performed by some other unwinder.
+#
+# But, prior to returning None, it will attempt to obtain the value
+# associated with a symbol via a call to gdb.parse_and_eval(). In
+# the course of doing this evaluation, GDB will potentially access
+# some frames, leading to the possibility of a recursive invocation of
+# this unwinder. If that should happen, code contained herein detects
+# that and prints a message which will cause some of the associated
+# tests to FAIL.
+
+import gdb
+from gdb.unwinder import Unwinder
+
+class TestUnwinder(Unwinder):
+
+ count = 0
+
+ @classmethod
+ def reset_count (cls):
+ cls.count = 0
+
+ @classmethod
+ def inc_count (cls):
+ cls.count += 1
+
+ def __init__(self):
+ Unwinder.__init__(self, "test unwinder")
+ self.recurse_level = 0
+
+ def __call__(self, pending_frame):
+
+
+ if self.recurse_level > 0:
+ gdb.write("TestUnwinder: Recursion detected - returning early.\n")
+ return None
+
+ self.recurse_level += 1
+ TestUnwinder.inc_count()
+
+ try:
+ val = gdb.parse_and_eval("undefined_symbol")
+
+ except Exception as arg:
+ pass
+
+ self.recurse_level -= 1
+
+ return None
+
+gdb.unwinder.register_unwinder(None, TestUnwinder(), True)
+gdb.write("Python script imported\n")
projects / binutils-gdb.git / commitdiff