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

# Copyright (C) 2015-2024 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 verifies that frame
# unwinders can be implemented in Python.

load_lib gdb-python.exp

require allow_python_tests

standard_testfile

# Stack protection can make the stack look a bit different, breaking the
# assumptions this test has about its layout.

set flags "additional_flags=-fno-stack-protector"

if { [prepare_for_testing "failed to prepare" ${testfile} ${srcfile} "debug $flags"] } {
    return -1
}

# This test runs on a specific platform.
require is_x86_64_m64_target

# The following tests require execution.

if {![runto_main]} {
    return 0
}

# Check for the corrupt backtrace.
proc check_for_broken_backtrace {testname} {
    gdb_test_sequence "where" $testname {
	"\\r\\n#0 .* corrupt_frame_inner \\(\\) at "
	"\\r\\n#1 .* corrupt_frame_outer \\(\\) at "
	"Backtrace stopped: frame did not save the PC"
    }
}

# Check for the correct backtrace.
proc check_for_fixed_backtrace {testname} {
    gdb_test_sequence "where" $testname {
	"\\r\\n#0 .* corrupt_frame_inner \\(\\) at "
	"\\r\\n#1 .* corrupt_frame_outer \\(\\) at "
	"\\r\\n#2 .* main \\(.*\\) at"
    }
}

# Check the 'info unwinder' output.
proc check_info_unwinder {testname enabled} {
    if {$enabled} {
	set suffix ""
    } else {
	set suffix " \\\[disabled\\\]"
    }

    gdb_test_sequence "info unwinder" $testname \
	[list \
	     "Global:" \
	     "  test unwinder${suffix}"]
}

set pyfile [gdb_remote_download host ${srcdir}/${subdir}/${testfile}.py]

gdb_breakpoint [gdb_get_line_number "break backtrace-broken"]

gdb_continue_to_breakpoint "break backtrace-broken"

check_for_broken_backtrace "Backtrace is initially broken"

gdb_test "source ${pyfile}" "Python script imported" \
    "import python scripts"

check_info_unwinder "info unwinder after loading script" on

check_for_fixed_backtrace "check backtrace after loading unwinder"

# Check that the Python unwinder frames can be flushed / released.
gdb_test "maint flush register-cache" "Register cache flushed\\." "flush frames"

check_for_fixed_backtrace "check backtrace after flush"

# Try to disable the unwinder but instead set the enabled field to a
# non boolean value.  This should fail.  Check the 'info unwinder'
# output to be sure.
gdb_test "python global_test_unwinder.enabled = \"off\"" \
    [multi_line \
	 "TypeError.*: incorrect type for enabled attribute: <class 'str'>" \
	 "Error occurred in Python.*"]
check_info_unwinder "info unwinder after failed disable" on

# While we're doing silly stuff, lets try to change the name of this
# unwider.  Doing this is bad as the new name might clash with an
# already registered name, which violates the promises made during
# 'register_unwinder'.
set pattern_1 "can't set attribute(?: 'name')?"
set pattern_2 "property 'name' of 'TestUnwinder' object has no setter"
gdb_test "python global_test_unwinder.name = \"foo\"" \
    [multi_line \
	 "AttributeError.*: (?:${pattern_1}|${pattern_2})" \
	 "Error occurred in Python.*"]
check_info_unwinder "info unwinder after failed name change" on

# Now actually disable the unwinder by manually adjusting the
# 'enabled' attribute.  Check that the stack is once again broken, and
# that the unwinder shows as disabled in the 'info unwinder' output.
gdb_test_no_output "python global_test_unwinder.enabled = False"
check_for_broken_backtrace "stack is broken after disabling"
check_info_unwinder "info unwinder after manually disabling" off

# Now enable the unwinder using the 'enable unwinder' command.
gdb_test "enable unwinder global \"test unwinder\"" \
    "1 unwinder enabled"
check_for_fixed_backtrace "check backtrace after enabling with command"
check_info_unwinder "info unwinder after command enabled" on

# And now disable using the command and check the stack is once again
# broken, and that the 'info unwinder' output updates correctly.
gdb_test "disable unwinder global \"test unwinder\"" \
    "1 unwinder disabled"
check_for_broken_backtrace "stack is broken after command disabling"
check_info_unwinder "info unwinder after command disabling" off

# Check that invalid register names and values cause errors.
gdb_test "python print(add_saved_register_errors\[\"unknown_name\"\])" \
    "Bad register" \
    "add_saved_register error when an unknown register name is used"
gdb_test "python print(add_saved_register_errors\[\"unknown_number\"\])" \
    "Bad register" \
    "add_saved_register error when an unknown register number is used"
gdb_test "python print(add_saved_register_errors\[\"bad_value\"\])" \
    "argument 2 must be gdb.Value, not int" \
    "add_saved_register error when invalid register value is used"
gdb_test "python print(read_register_error)" "Bad register" \
    "read_register error"

# Try to create an unwinder object with a non-string name.
gdb_test "python obj = simple_unwinder(True)" \
    [multi_line \
	 "TypeError.*: incorrect type for name: <class 'bool'>" \
	 "Error occurred in Python.*"]

# Now register the simple_unwinder with a valid name, and use the
# unwinder to capture a PendingFrame object.
gdb_test_no_output "python obj = simple_unwinder(\"simple\")"
gdb_test_no_output "python gdb.unwinder.register_unwinder(None, obj)"
check_for_broken_backtrace "backtrace to capture a PendingFrame object"

# Check the captured PendingFrame is not valid.
gdb_test "python print(captured_pending_frame.is_valid())" "False"

# Check the __repr__ of an invalid PendingFrame.
gdb_test "python print(repr(captured_pending_frame))" \
    "<gdb.PendingFrame \\(invalid\\)>"

# Check the __repr__ of an UnwindInfo for an invalid PendingFrame.
gdb_test "python print(captured_unwind_info)"
gdb_test "python print(repr(captured_unwind_info))" \
    "<gdb.UnwindInfo for an invalid frame>"

# Check the repr of a PendingFrame that was copied (as a string) at a
# time the PendingFrame was valid.
gdb_test "python print(captured_pending_frame_repr)" \
    "<gdb.PendingFrame level=0, sp=$hex, pc=$hex>"

# Check the repr of an UnwindInfo that was copied (as a string) at a
# time the UnwindInfo was valid.
gdb_test "python print(captured_unwind_info_repr)" \
    "<gdb.UnwindInfo frame #0, saved_regs=\\(rip, rbp, rsp\\)>"

# Call methods on the captured gdb.PendingFrame and check we see the
# expected error.
gdb_test_no_output "python pf = captured_pending_frame"
foreach cmd {"pf.read_register(\"pc\")" \
		 "pf.create_unwind_info(None)" \
		 "pf.architecture()" \
		 "pf.level()" \
		 "pf.name()" \
		 "pf.pc()" \
		 "pf.language()" \
		 "pf.find_sal()" \
		 "pf.block()" \
		 "pf.function()" } {
    gdb_test "python $cmd" \
	[multi_line \
	     "ValueError.*: gdb\\.PendingFrame is invalid\\." \
	     "Error occurred in Python.*"]
}

# Turn on the useful unwinder so we have the full backtrace again, and
# disable the simple unwinder -- because we can!
gdb_test "enable unwinder global \"test unwinder\"" \
    "1 unwinder enabled" \
    "re-enable 'test unwinder' so we can check PendingFrame methods"
gdb_test "disable unwinder global \"simple\"" \
    "1 unwinder disabled"
check_for_fixed_backtrace \
    "check backtrace before testing PendingFrame methods"

# Turn the 'simple' unwinder back on.
gdb_test "enable unwinder global \"simple\"" \
    "1 unwinder enabled"

# Replace the "simple" unwinder with a new version that doesn't set
# the 'sp' attribute.  Also the 'pc' attribute is invalid, but we'll
# hit the missing 'sp' error first.
with_test_prefix "frame-id 'sp' is None" {
    gdb_test_no_output "python obj = simple_unwinder(\"simple\", None, \"xyz\")"
    gdb_test_no_output "python gdb.unwinder.register_unwinder(None, obj, replace=True)"
    gdb_test_no_output "python captured_pending_frame = None"
    gdb_test "backtrace" \
	"Python Exception <class 'ValueError'>: frame_id should have 'sp' attribute\\.\r\n.*"
}

# Replace the "simple" unwinder with a new version that sets the 'sp'
# attribute to an invalid value.  Also the 'pc' attribute is invalid, but we'll
# hit the invalid 'sp' error first.
with_test_prefix "frame-id 'sp' is invalid" {
    gdb_test_no_output "python obj = simple_unwinder(\"simple\", \"jkl\", \"xyz\")"
    gdb_test_no_output "python gdb.unwinder.register_unwinder(None, obj, replace=True)"
    gdb_test_no_output "python captured_pending_frame = None"
    gdb_test "backtrace" \
	"Python Exception <class 'ValueError'>: invalid literal for int\\(\\) with base 10: 'jkl'\r\n.*"
}

# Replace the "simple" unwinder with a new version that sets the 'sp'
# to a valid value, but set the 'pc' attribute to an invalid value.
with_test_prefix "frame-id 'pc' is invalid" {
    gdb_test_no_output "python obj = simple_unwinder(\"simple\", 0x123, \"xyz\")"
    gdb_test_no_output "python gdb.unwinder.register_unwinder(None, obj, replace=True)"
    gdb_test_no_output "python captured_pending_frame = None"
    gdb_test "backtrace" \
	"Python Exception <class 'ValueError'>: invalid literal for int\\(\\) with base 10: 'xyz'\r\n.*"
}

# Gather information about every frame.
gdb_test_no_output "python capture_all_frame_information()"
gdb_test_no_output "python gdb.newest_frame().select()"
gdb_test_no_output "python pspace = gdb.selected_inferior().progspace"
gdb_test_no_output "python obj = validating_unwinder()"
gdb_test_no_output "python gdb.unwinder.register_unwinder(pspace, obj)"

check_for_fixed_backtrace \
    "check backtrace to validate all information"

gdb_test_no_output "python check_all_frame_information_matched()"

# Check we can't sub-class from gdb.UnwindInfo.
gdb_test_multiline "Sub-class gdb.UnwindInfo " \
    "python" "" \
    "class my_unwind_info(gdb.UnwindInfo):" "" \
    "  def __init__(self):" "" \
    "    pass" "" \
    "end" \
    [multi_line \
	 "TypeError.*: type 'gdb\\.UnwindInfo' is not an acceptable base type" \
	 "Error occurred in Python.*"]

# Check we can't directly instantiate a gdb.UnwindInfo.
gdb_test "python uw = gdb.UnwindInfo()" \
    [multi_line \
     "TypeError.*: cannot create 'gdb\\.UnwindInfo' instances" \
     "Error occurred in Python.*"]