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 gdb_breakpoint "ccc"
  49
  50 gdb_continue_to_breakpoint "ccc"
  51
  52 # If the unwinder is active, the usage count will increment while
  53 # running to the breakpoint.  Reset it prior to doing the backtrace.
  54 gdb_test_no_output "python TestUnwinder.reset_count()"
  55
  56 # The python based unwinder should be called a number of times while
  57 # generating the backtrace, but its sniffer always returns None.  So
  58 # it doesn't really contribute to generating any of the frames below.
  59 #
  60 # But that's okay.  Our goal here is to make sure that GDB doesn't
  61 # get hung up in potentially infinite recursion when invoking the
  62 # Python-based unwinder.
  63
  64 gdb_test_sequence "bt"  "backtrace" {
  65     "\\r\\n#0 .* ccc \\(arg=789\\) at "
  66     "\\r\\n#1 .* bbb \\(arg=456\\) at "
  67     "\\r\\n#2 .* aaa \\(arg=123\\) at "
  68     "\\r\\n#3 .* main \\(.*\\) at"
  69 }
  70
  71 # Test that the python-based unwinder / sniffer was actually called
  72 # during generation of the backtrace.
  73 gdb_test "python print(TestUnwinder.count > 0)" "True"