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Elixir Cross Referencer

# Copyright (C) 2014-2020 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/>.  */

# Test that "signal FOO" behaves correctly when we have multiple
# threads that have stopped for a signal.

if [target_info exists gdb,nosignals] {
    verbose "Skipping ${testfile}.exp because of nosignals."
    return -1
}

standard_testfile

if {[gdb_compile_pthreads "${srcdir}/${subdir}/${srcfile}" "${binfile}" \
	 executable { debug }] != "" } {
    return -1
}

# Run the test proper.  SCHEDLOCK indicates which variant (around
# scheduler-locking) of the test to perform.

proc test { schedlock } {
    global srcfile binfile

    with_test_prefix "schedlock $schedlock" {
	clean_restart ${binfile}

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

	gdb_test "handle SIGUSR1 stop print pass"
	gdb_test "handle SIGUSR2 stop print pass"

	gdb_test "break all_threads_started" "Breakpoint .* at .*$srcfile.*"

	# Create threads one at a time, to insure stable thread
	# numbers between runs and targets.
	gdb_test "break thread_function" "Breakpoint .* at .*$srcfile.*"
	gdb_test "continue" "thread_function.*" "thread 2 created"
	gdb_test "continue" "thread_function.*" "thread 3 created"

	gdb_test "continue" "all_threads_started.*"

	# Using schedlock, let the main thread queue a signal for each
	# non-main thread.
	gdb_test_no_output "set scheduler-locking on"

	gdb_test "break all_threads_signalled" "Breakpoint .* at .*$srcfile.*"
	gdb_test "continue" "all_threads_signalled.*"

	gdb_test "info threads" "\\\* 1\[ \t\]+Thread.*" "thread 1 selected"

	# With schedlock still enabled, let each thread report its
	# signal.

	gdb_test "thread 3" "Switching to thread 3.*"
	gdb_test "continue" "Thread 3 .*received signal SIGUSR2.*" "stop with SIGUSR2"
	gdb_test "thread 2" "Switching to thread 2.*"
	gdb_test "continue" "Thread 2 .*received signal SIGUSR1.*" "stop with SIGUSR1"

	gdb_test "break handler_sigusr1" "Breakpoint .* at .*$srcfile.*"
	gdb_test "break handler_sigusr2" "Breakpoint .* at .*$srcfile.*"

	set handler_re "Breakpoint .*, handler_sigusr. \\(sig=.*\\) at .*"

	# Now test the "signal" command with either scheduler locking
	# enabled or disabled.

	if { $schedlock == "off" } {
	    # With scheduler locking off, switch to the main thread
	    # and issue "signal 0".  "signal 0" should then warn that
	    # two threads have signals that will be delivered.  When
	    # we let the command proceed, a signal should be
	    # delivered, and thus the corresponding breakpoint in the
	    # signal handler should trigger.

	    gdb_test_no_output "set scheduler-locking off"
	    gdb_test "thread 1" "Switching to thread 1.*"

	    set queried 0
	    set test "signal command queries"
	    gdb_test_multiple "signal 0" $test {
		-re "stopped with.*stopped with.*stopped with.*Continue anyway.*y or n. $" {
		    fail "$test (too many threads noted)"
		    set queried 1
		}
		-re "stopped with signal SIGUSR.*\r\nContinuing .*still deliver .*Continue anyway.*y or n. $" {
		    pass $test
		    set queried 1
		}
		-re "Continue anyway.*y or n. $" {
		    fail "$test (no threads noted)"
		    set queried 1
		}
	    }

	    # Continuing should stop in one of the signal handlers.
	    # Which thread runs first is not determinate.
	    if {$queried} {
		gdb_test "y" "$handler_re" "one signal delivered"
	    }

	    # Continuing a second time should stop in the other
	    # handler.
	    with_test_prefix "second signal" {
		gdb_test "continue" "$handler_re" "signal delivered"
	    }
	} else {
	    # With scheduler locking on, stay with thread 2 selected,
	    # and try to deliver its signal explicitly.  The "signal"
	    # command should then warn that one other thread has a
	    # signal that will be delivered.  When we let the command
	    # proceed, the current thread's signal should be
	    # delivered, and thus the corresponding breakpoint in the
	    # signal handler should trigger.
	    gdb_test "signal SIGUSR1" \
		"Breakpoint .*, handler_sigusr1 \\(sig=.*\\) at .*" \
		"signal command does not query, signal delivered"

	    with_test_prefix "second signal" {
		# The other thread had stopped for a signal too, and
		# it wasn't resumed yet.  Disabling schedlock and
		# trying "signal 0" from the main thread should warn
		# again.
		gdb_test_no_output "set scheduler-locking off"

		set queried 0
		set test "signal command queries"
		gdb_test_multiple "signal 0" $test {
		    -re "stopped with.*stopped with.*Continue anyway.*y or n. $" {
			fail "$test (too many threads noted)"
			set queried 1
		    }
		    -re "stopped with signal SIGUSR.*\r\nContinuing .*still deliver .*Continue anyway.*y or n. $" {
			pass $test
			set queried 1
		    }
		    -re "Continue anyway.*y or n. $" {
			fail "$test (no threads noted)"
			set queried 1
		    }
		}

		if {$queried} {
		    gdb_test "y" "Breakpoint .*, handler_sigusr2 \\(sig=.*\\) at .*" "signal delivered"
		}
	    }
	}

	# Both threads got their signal.  Continuing again should
	# neither intercept nor deliver any other signal.
	gdb_test "b end" "Breakpoint .* at .*$srcfile.*"
	gdb_test "continue" "end .*" "no more signals"
    }
}

foreach schedlock {"off" "on"} {
    test $schedlock
}