1# Copyright (C) 2016-2019 Free Software Foundation, Inc. 2 3# This program is free software; you can redistribute it and/or modify 4# it under the terms of the GNU General Public License as published by 5# the Free Software Foundation; either version 3 of the License, or 6# (at your option) any later version. 7# 8# This program is distributed in the hope that it will be useful, 9# but WITHOUT ANY WARRANTY; without even the implied warranty of 10# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 11# GNU General Public License for more details. 12# 13# You should have received a copy of the GNU General Public License 14# along with this program. If not, see <http://www.gnu.org/licenses/>. 15 16# This file is part of the GDB testsuite. It is used to verify that 17# GDB does not recurse infinitely when calling gdb.parse_and_eval() in 18# the course of sniffing a frame in a Python unwinder. 19 20# The unwinder has been constructed so that, should recursion occur, 21# it will be detected in the unwinder so that we won't need to wait 22# for a timeout. 23 24 25load_lib gdb-python.exp 26 27standard_testfile 28 29if { [prepare_for_testing "failed to prepare" ${testfile} ${srcfile}] } { 30 return -1 31} 32 33# Skip all tests if Python scripting is not enabled. 34if { [skip_python_tests] } { continue } 35 36set pyfile [gdb_remote_download host ${srcdir}/${subdir}/${testfile}.py] 37 38gdb_test "source ${pyfile}" "Python script imported" \ 39 "import python scripts" 40 41# The following tests require execution. 42 43if ![runto_main] then { 44 fail "can't run to main" 45 return 0 46} 47 48 49proc cont_and_backtrace { tst } { 50 51 with_test_prefix $tst { 52 gdb_breakpoint "ccc" 53 54 # We're testing different code paths within the unwinder's sniffer. 55 # Set the current path to be tested here. 56 gdb_test_no_output "python TestUnwinder.set_test(\"$tst\")" \ 57 "set code path within python unwinder to $tst" 58 59 # If the unwinder is active, the usage count will increment while 60 # running to the breakpoint. Reset it prior to doing the backtrace. 61 gdb_test_no_output "python TestUnwinder.reset_count()" \ 62 "reset count" 63 64 gdb_continue_to_breakpoint "ccc" 65 66 # The python based unwinder should be called a number of times while 67 # generating the backtrace, but its sniffer always returns None. So 68 # it doesn't really contribute to generating any of the frames below. 69 # 70 # But that's okay. Our goal here is to make sure that GDB doesn't 71 # get hung up in potentially infinite recursion when invoking the 72 # Python-based unwinder. 73 74 gdb_test_sequence "bt" "backtrace" { 75 "\\r\\n#0 .* ccc \\(arg=789\\) at " 76 "\\r\\n#1 .* bbb \\(arg=456\\) at " 77 "\\r\\n#2 .* aaa \\(arg=123\\) at " 78 "\\r\\n#3 .* main \\(.*\\) at" 79 } 80 81 # Test that the python-based unwinder / sniffer was actually called 82 # during generation of the backtrace. 83 gdb_test "python print(TestUnwinder.count > 0)" "True" \ 84 "python unwinder called" 85 } 86} 87 88cont_and_backtrace "check_undefined_symbol" 89cont_and_backtrace "check_user_reg_pc" 90cont_and_backtrace "check_pae_pc" 91