path: root/gdb/testsuite/gdb.base/signals.exp

if $tracelevel then {
	strace $tracelevel
}

set prms_id 0
set bug_id 0

gdb_reinitialize_dir $srcdir/$subdir
set binfile $objdir/$subdir/signals

if ![file exists $binfile] then {
    perror "$binfile does not exist."
    return 0
}

proc signal_tests_1 {} {
    global prompt
    if [runto main] then {
	gdb_test "next" "signal \[(\]+SIGUSR1" \
		"next over signal \[(\]SIGALRM, handler\[)\]+"
	gdb_test "next" "alarm \[(\]" \
		"next over signal \[(\]+SIGUSR1, handler\[)\]+"
	gdb_test "next" "\[+\]+count" \
		"next over alarm (1)"
	# An alarm has been signaled, give the signal time to get delivered.
	exec sleep 2

	# i386 BSD currently fails the next test with a SIGTRAP.
	setup_xfail "i*86-*-bsd*"
	# But Dynix has a DECR_PC_AFTER_BREAK of zero, so the failure
	# is shadowed by hitting the through_sigtramp_breakpoint.
	clear_xfail "i*86-sequent-bsd*"
	# Univel SVR4 i386 continues instead of stepping.
	setup_xfail "i*86-univel-sysv4*"
	send "next\n"
	expect {
	    -re "alarm .*$prompt $" { pass "next to 2nd alarm (1)" }
	    -re "Program received signal SIGTRAP.*first.*$prompt $" {

		# This can happen on machines that have a trace flag
		# in their PS register.
		# The trace flag in the PS register will be set due to
		# the `next' command.
		# Before calling the signal handler, the PS register
		# is pushed along with the context on the user stack.
		# When the signal handler has finished, it reenters the
		# the kernel via a sigreturn syscall, which restores the
		# PS register along with the context.
		# If the kernel erroneously does not clear the trace flag
		# in the pushed context, gdb will receive a SIGTRAP from
		# the set trace flag in the restored context after the
		# signal handler has finished.

		# I do not yet understand why the SIGTRAP does not occur
		# after stepping the instruction at the restored PC on
		# i386 BSDI 1.0 systems.

		# Note that the vax under Ultrix also exhibits
		# this behaviour (it is uncovered by the `continue from
		# a break in a signal handler' test below).
		# With this test the failure is shadowed by hitting the
		# through_sigtramp_breakpoint upon return from the signal
		# handler.

		fail "next to 2nd alarm (1) (probably kernel bug)"
		gdb_test "next" "alarm" "next to 2nd alarm (1)"
	    }
	    -re "Program exited with code.*$prompt $" {

		# This is apparently a bug in the UnixWare kernel (but
		# has not been investigated beyond the
		# resume/target_wait level, and has not been reported
		# to Univel).  If it steps when a signal is pending,
		# it does a continue instead.  I don't know whether
		# there is a workaround.

		# Perhaps this problem exists on other SVR4 systems;
		# but (a) we have no reason to think so, and (b) if we
		# put a wrong xfail here, we never get an XPASS to let
		# us know that it was incorrect (and then if such a
		# configuration regresses we have no way of knowing).
		# Solaris is not a relevant data point either way
		# because it lacks single stepping.

		fail "'next' behaved as 'continue'"
		return 0
	    }
	    -re ".*$prompt $" { fail "next to 2nd alarm (1)" }
	    timeout { fail "next to 2nd alarm (1); (timeout)" }
	    eof { fail "next to 2nd alarm (1); (eof)" }
	}

	gdb_test "break handler" "Breakpoint \[0-9\]*"
	gdb_test "next" "\[+\]+count" "next to 2nd ++count"
	# An alarm has been signaled, give the signal time to get delivered.
	exec sleep 2

	set bash_bug 0
	send "next\n"
	expect {
	    -re "Breakpoint.*handler.*$prompt $" { pass "next" }
	    -re "Program received signal SIGEMT.*$prompt $" {
		# Bash versions before 1.13.5 cause this behaviour
		# by blocking SIGTRAP.
		fail "next (known problem with bash versions before 1.13.5)"
		set bash_bug 1
		gdb_test "signal 0" "Breakpoint.*handler"
	    }
	    -re ".*$prompt $" { fail "next" }
	    timeout { fail "(timeout)" }
	    eof { fail "(eof)" }
	}

	# This doesn't test that main is frame #2, just that main is frame
	# #2, #3, or higher.  At some point this should be fixed (but
	# it quite possibly would introduce new FAILs on some systems).
	gdb_test "backtrace" "#0.*handler.*#1.*#2.*main"

	gdb_test "break func1" "Breakpoint \[0-9\]*"
	gdb_test "break func2" "Breakpoint \[0-9\]*"

	# Vax Ultrix and i386 BSD currently fail the next test with
	# a SIGTRAP, but with different symptoms.
	setup_xfail "vax-*-ultrix*"
	setup_xfail "i*86-*-bsd*"
	send "continue\n"
	expect {
	    -re "Breakpoint.*func1.*$prompt $" { pass "continue" }
	    -re "Program received signal SIGTRAP.*second.*$prompt $" {

		# See explanation for `next to 2nd alarm (1)' fail above.
		# We did step into the signal handler, hit a breakpoint
		# in the handler and continued from the breakpoint.
		# The set trace flag in the restored context is causing
		# the SIGTRAP, without stepping an instruction.

		fail "continue (probably kernel bug)"
		gdb_test "continue" "Breakpoint.*func1"
	    }
	    -re "Program received signal SIGTRAP.*func1 ..;.*$prompt $" {

		# On the vax under Ultrix the set trace flag in the restored
		# context is causing the SIGTRAP, but after stepping one
		# instruction, as expected.

		fail "continue (probably kernel bug)"
		gdb_test "continue" "Breakpoint.*func1"
	    }
	    -re ".*$prompt $" { fail "continue" }
	    default { fail "continue" }
	}
	gdb_test "signal SIGUSR1" "Breakpoint.*handler"

	# Will tend to wrongly require an extra continue.

	# The problem here is that the breakpoint at func1 will be
	# inserted, and when the system finishes with the signal
	# handler it will try to execute there.  For GDB to try to
	# remember that it was going to step over a breakpoint when a
	# signal happened, distinguish this case from the case where
	# func1 is called from the signal handler, etc., seems
	# exceedingly difficult.  So don't expect this to get fixed
	# anytime soon.

	setup_xfail "*-*-*"
	send "continue\n"
	expect {
	    -re "Breakpoint.*func2.*$prompt $" { pass "continue" }
	    -re "Breakpoint.*func1.*$prompt $" {
	    	fail "continue"
		gdb_test "continue" "Breakpoint.*func2"
	    }
	    -re ".*$prompt $" { fail "continue" }
	    default { fail "continue" }
	}

	exec sleep 2

        # GDB yanks out the breakpoints to step over the breakpoint it
        # stopped at, which means the breakpoint at handler is yanked.
	# But if NO_SINGLE_STEP, we won't get another chance to reinsert
	# them (at least not with procfs, where we tell the kernel not
	# to tell gdb about `pass' signals).  So the fix would appear to
	# be to just yank that one breakpoint when we step over it.

	setup_xfail "sparc-*-*"
	setup_xfail "rs6000-*-*"

	# A faulty bash will not step the inferior into sigtramp on sun3.
	if {$bash_bug} then {
	    setup_xfail "m68*-*-sunos4*"
	}

	gdb_test "continue" "Breakpoint.*handler"

	# If the NO_SINGLE_STEP failure happened, we have already exited.
	# If we succeeded a continue will return from the handler to func2.
	# GDB now has `forgotten' that it intended to step over the
	# breakpoint at func2 and will stop at func2.
	setup_xfail "*-*-*"
	# The sun3 with a faulty bash will also be `forgetful' but it
	# already got the spurious stop at func2 and this continue will work.
	if {$bash_bug} then {
	     clear_xfail "m68*-*-sunos4*"
	}
	gdb_test "continue" "Program exited with code 010"
    }
}

# On a few losing systems, ptrace (PT_CONTINUE) or ptrace (PT_STEP)
# causes pending signals to be cleared, which causes these tests to
# get nowhere fast.  This is totally losing behavior (perhaps there
# are cases in which is it useful but the user needs more control,
# which they mostly have in GDB), but some people apparently think it
# is a feature.  It is documented in the ptrace manpage on Motorola
# Delta Series sysV68 R3V7.1 and on HPUX 9.0.  Even the non-HPUX PA
# OSes (BSD and OSF/1) seem to have figured they had to copy this
# braindamage.

if {[ istarget "m68*-motorola-*" ] || [ istarget "hppa*-*-bsd*" ] ||
    [ istarget "*-*-hpux*" ] || [ istarget "hppa*-*-osf*" ]} then {
  setup_xfail "*-*-*"
  fail "ptrace loses on signals on this target"
  return 0
}

gdb_exit
gdb_start
gdb_load $binfile
signal_tests_1

# Force a resync, so we're looking at the right prompt.  On SCO we
# were getting out of sync (I don't understand why).
send "p 1+1\n"
expect {
    -re "= 2.*$prompt $" {}
    -re ".*$prompt $" { perror "sync trouble in signals.exp" }
    default { perror "sync trouble in signals.exp" }
}

if [runto main] then {
    gdb_test "break handler if 0" "Breakpoint \[0-9\]*"
    gdb_test "set \$handler_breakpoint_number = \$bpnum" ""

    # Get to the point where a signal is waiting to be delivered
    gdb_test "next" "signal \[(\]+SIGUSR1"
    gdb_test "next" "alarm \[(\]+"
    gdb_test "next" "\[+\]+count"
    # Give the signal time to get delivered
    exec sleep 2

    # Now call a function.  When GDB tries to run the stack dummy,
    # it will hit the breakpoint at handler.  Provided it doesn't
    # lose its cool, this is not a problem, it just has to note
    # that the breakpoint condition is false and keep going.

    gdb_test "p func1 ()" "^p func1 \[)(\]+\r\n.\[0-9\]* = void"

    # Make sure the count got incremented.

    # Haven't investigated this xfail
    setup_xfail "rs6000-*-*"
    gdb_test "p count" "= 2"
    if [istarget "rs6000-*-*"] { return 0 }

    gdb_test "condition \$handler_breakpoint_number" "now unconditional"
    gdb_test "next" "alarm \[(\]+"
    gdb_test "next" "\[+\]+count"
    exec sleep 2

    # This time we stop when GDB tries to run the stack dummy.
    # So it is OK that we do not print the return value from the function.
    gdb_test "p func1 ()" \
"Breakpoint \[0-9\]*, handler.*
The program being debugged stopped while in a function called from GDB"
    # But we should be able to backtrace...
    gdb_test "bt" "#0.*handler.*#1.*#2.*main"
    # ...and continue...
    gdb_test "continue" "Continuing"
    # ...and then count should have been incremented
    gdb_test "p count" "= 5"
}

return 0