gdb/testsuite/gdb.python/py-recurse-unwind.exp

   1 # Copyright (C) 2016 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
  25 load_lib gdb-python.exp
  26
  27 standard_testfile
  28
  29 if { [prepare_for_testing ${testfile}.exp ${testfile} ${srcfile}] } {
  30     return -1
  31 }
  32
  33 # Skip all tests if Python scripting is not enabled.
  34 if { [skip_python_tests] } { continue }
  35
  36 set pyfile [gdb_remote_download host ${srcdir}/${subdir}/${testfile}.py]
  37
  38 gdb_test "source ${pyfile}" "Python script imported" \
  39          "import python scripts"
  40
  41 # The following tests require execution.
  42
  43 if ![runto_main] then {
  44     fail "can't run to main"
  45     return 0
  46 }
  47
  48
  49 proc 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
  88 cont_and_backtrace "check_undefined_symbol"
  89 cont_and_backtrace "check_user_reg_pc"
  90 cont_and_backtrace "check_pae_pc"