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/* $NetBSD: t_spawnattr.c,v 1.6 2022/05/23 21:46:12 andvar Exp $ */

/*-
 * Copyright (c) 2012 The NetBSD Foundation, Inc.
 * All rights reserved.
 *
 * This code is derived from software contributed to The NetBSD Foundation
 * by Charles Zhang <charles@NetBSD.org> and
 * Martin Husemann <martin@NetBSD.org>.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 *
 * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
 * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
 * POSSIBILITY OF SUCH DAMAGE.
 */
#include <sys/cdefs.h>
__RCSID("$NetBSD: t_spawnattr.c,v 1.6 2022/05/23 21:46:12 andvar Exp $");

#include <sys/param.h>
#include <atf-c.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <errno.h>
#include <fcntl.h>
#include <sched.h>
#include <signal.h>
#include <spawn.h>
#include <unistd.h>
#include <sys/wait.h>

static int
get_different_scheduler(void)
{
	/*
	 * We don't want to use SCHED_OTHER because it does not have
	 * different priorities.
	 */

	/* get current schedule policy */
	switch (sched_getscheduler(0)) {
	case SCHED_RR:
		return SCHED_FIFO;
	case SCHED_FIFO:
	case SCHED_OTHER:
		return SCHED_RR;
	default:
		abort();
	}
}

static int
get_different_priority(int scheduler)
{
	int min, max, new, priority;
	struct sched_param param;

	/* Get the priority range for the new scheduler */
	max = sched_get_priority_max(scheduler);
	min = sched_get_priority_min(scheduler);

	sched_getparam(0, &param);
	priority = param.sched_priority;
	
	/* new schedule policy */
	for (new = min; new <= max; new++)
		if (priority != new)
			break;
	
	ATF_REQUIRE_MSG(priority != new, "could not find different priority");
	printf("min %d max %d for scheduler %d, returning %d\n",
	    min, max, scheduler, new);
	return new;
}

ATF_TC(t_spawnattr);

ATF_TC_HEAD(t_spawnattr, tc)
{
	atf_tc_set_md_var(tc, "require.user", "root");
	atf_tc_set_md_var(tc, "descr",
	    "Tests posix_spawn with scheduler attributes");
}

ATF_TC_BODY(t_spawnattr, tc)
{
	int pid, scheduler, child_scheduler, priority, status, err, pfd[2];
	char helper_arg[128];
	char * const args[] = { __UNCONST("h_spawnattr"), helper_arg, NULL };
	struct sched_param sp, child_sp;
	sigset_t sig;
	posix_spawnattr_t attr;
	char helper[FILENAME_MAX];

	/*
	 * create a pipe to control the child
	 */
	err = pipe(pfd);
	ATF_REQUIRE_MSG(err == 0, "could not create pipe, errno %d", errno);
	sprintf(helper_arg, "%d", pfd[0]);

	posix_spawnattr_init(&attr);

	scheduler = get_different_scheduler();
	priority = get_different_priority(scheduler);
	sp.sched_priority = priority;
	printf("using scheduler %d, priority %d\n", scheduler, priority);
	
	sigemptyset(&sig);
	sigaddset(&sig, SIGUSR1);

	posix_spawnattr_setflags(&attr, POSIX_SPAWN_SETSCHEDULER | 
		POSIX_SPAWN_SETSCHEDPARAM | POSIX_SPAWN_SETPGROUP |
		POSIX_SPAWN_SETSIGMASK | POSIX_SPAWN_SETSIGDEF |
		POSIX_SPAWN_SETSIGDEF); 
	posix_spawnattr_setpgroup(&attr, 0);
	posix_spawnattr_setschedparam(&attr, &sp);
	posix_spawnattr_setschedpolicy(&attr, scheduler);
	posix_spawnattr_setsigmask(&attr, &sig);
	posix_spawnattr_setsigdefault(&attr, &sig);

	sprintf(helper, "%s/h_spawnattr",
	    atf_tc_get_config_var(tc, "srcdir"));
	err = posix_spawn(&pid, helper, NULL, &attr, args, NULL);
	ATF_REQUIRE_MSG(err == 0, "error %d", err);

	child_scheduler = sched_getscheduler(pid);
	ATF_REQUIRE_MSG(scheduler == child_scheduler,
	    "scheduler = %d, child_scheduler = %d, pid %d, errno %d",
	    scheduler, child_scheduler, pid, errno);

	sched_getparam(pid, &child_sp);
	ATF_REQUIRE_MSG(child_sp.sched_priority == sp.sched_priority,
	    "priority is: %d, but we requested: %d",
	    child_sp.sched_priority, sp.sched_priority);

	ATF_REQUIRE_MSG(pid == getpgid(pid), "child pid: %d, child pgid: %d",
	    pid, getpgid(pid));

	/* ready, let child go */
	write(pfd[1], "q", 1);
	close(pfd[0]);
	close(pfd[1]);

	/* wait and check result from child */
	waitpid(pid, &status, 0);
	ATF_REQUIRE(WIFEXITED(status) && WEXITSTATUS(status) == EXIT_SUCCESS);

	posix_spawnattr_destroy(&attr);
}

ATF_TC(t_spawn_resetids);

ATF_TC_HEAD(t_spawn_resetids, tc)
{
	atf_tc_set_md_var(tc, "descr",
	    "posix_spawn a child and with POSIX_SPAWN_RESETIDS flag");
}

ATF_TC_BODY(t_spawn_resetids, tc)
{
	char buf[FILENAME_MAX];
	char * const args[] = {
	     __UNCONST("h_spawn"), __UNCONST("--resetids"), NULL
	};
	posix_spawnattr_t attr;
	int err, status;
	pid_t pid;

	posix_spawnattr_init(&attr);
	posix_spawnattr_setflags(&attr, POSIX_SPAWN_RESETIDS);

	snprintf(buf, sizeof buf, "%s/h_spawn",
	    atf_tc_get_config_var(tc, "srcdir"));

	err = posix_spawn(&pid, buf, NULL, &attr, args, NULL);
	ATF_REQUIRE(err == 0);
	ATF_REQUIRE(pid > 0);
	waitpid(pid, &status, 0);
	ATF_REQUIRE(WIFEXITED(status) && WEXITSTATUS(status) == 0);

	posix_spawnattr_destroy(&attr);
}

ATF_TP_ADD_TCS(tp)
{
	ATF_TP_ADD_TC(tp, t_spawnattr);
	ATF_TP_ADD_TC(tp, t_spawn_resetids);

	return atf_no_error();
}