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Elixir Cross Referencer

# Copyright 2018-2020 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 test is about restarting execution of a forked application when
# using gdb extended remote target.
#
# There are two issues that the test tries to expose in GDB:
#
# 1. GDB would throw an assertion upon reconnecting to a remote target
# if there was more than one inferior already active in GDB, and
#
# 2. GDB would not prune transient inferiors from the inferior list
# when reconnecting to a remote target.  So, for example, an inferior
# created by GDB to track the child of a fork would usually be removed
# from the inferior list once the child exited.  However, reconnecting
# to a remote target would result in the child inferior remaining in
# the inferior list.

# This test is only for extended remote targets.
if {[target_info gdb_protocol] != "extended-remote"} {
    continue
}

# This test also makes use of 'detach-on-fork' which is not supported
# on all platforms.
if { ![istarget "*-*-linux*"] && ![istarget "*-*-openbsd*"] } then {
    continue
}

# And we need to be able to reconnect to gdbserver.
set gdbserver_reconnect_p 1
if { [info proc gdb_reconnect] == "" } {
    return 0
}

standard_testfile

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

# Core of the test.  DO_KILL_P controls whether we kill one of the
# inferiors before reconnecting.  And FOLLOW_CHILD_P controls whether
# we follow the child or the parent at the fork.
proc test_reload { do_kill_p follow_child_p } {
    global decimal
    global binfile

    clean_restart ${binfile}

    if ![runto_main] then {
	fail "can't run to main"
	return 0
    }

    # Set detach-on-fork off
    gdb_test_no_output "set detach-on-fork off"

    set live_inf_ptn "process $decimal"
    set dead_inf_ptn "<null>"

    if ${follow_child_p} {
	gdb_test_no_output "set follow-fork child"
	set parent_prefix " "
	set child_prefix "\\*"
	set parent_inf_after_kill_ptn ${live_inf_ptn}
	set child_inf_after_kill_ptn ${dead_inf_ptn}
    } else {
	gdb_test_no_output "set follow-fork parent"
	set parent_prefix "\\*"
	set child_prefix " "
	set parent_inf_after_kill_ptn ${dead_inf_ptn}
	set child_inf_after_kill_ptn ${live_inf_ptn}
    }

    gdb_breakpoint "breakpt"
    gdb_continue_to_breakpoint "breakpt"

    set ws "\[ \t\]+"
    set any_re "\[^\r\n\]+"
    set connection_re $any_re
    set executable_re $any_re

    gdb_test "info inferiors" \
	[multi_line \
	     "  Num${ws}Description${ws}Connection${ws}Executable${ws}" \
	     "${parent_prefix} 1${ws}${live_inf_ptn}${ws}${connection_re}${executable_re}" \
	     "${child_prefix} 2${ws}${live_inf_ptn}${ws}${connection_re}${executable_re}" ] \
	"Check inferiors at breakpoint"

    if { $do_kill_p } {
	# (Optional) Kill one of the inferiors.
	gdb_test "kill" \
	    "" \
	    "Kill inferior" \
	    "Kill the program being debugged.*y or n. $" \
	    "y"

	# Check the first inferior really did die.
	gdb_test "info inferiors" \
	    [multi_line \
		 "  Num${ws}Description${ws}Connection${ws}Executable${ws}" \
		 "${parent_prefix} 1${ws}${parent_inf_after_kill_ptn}${ws}${connection_re}${executable_re}" \
		 "${child_prefix} 2${ws}${child_inf_after_kill_ptn}${ws}${connection_re}${executable_re}" ] \
	    "Check inferior was killed"
    }

    # Disconnect, and reconnect to the target.
    gdb_test "disconnect" ".*"

    if { [gdb_reconnect] == 0 } {
	pass "reconnect after fork"
    } else {
	fail "reconnect after fork"
    }
}

# Run all combinations of the test.
foreach do_kill_p [list 1 0] {
    foreach follow_child_p [list 1 0] {
	with_test_prefix \
	    "kill: ${do_kill_p}, follow-child ${follow_child_p}" {
		test_reload ${do_kill_p} ${follow_child_p}
	    }
    }
}