/* $NetBSD: t_proc4.c,v 1.1 2021/10/10 17:43:15 thorpej Exp $ */

/*-
* Copyright (c) 2021 The NetBSD Foundation, Inc.
* All rights reserved.
*
* 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_proc4.c,v 1.1 2021/10/10 17:43:15 thorpej Exp $");

#include <sys/event.h>
#include <sys/time.h>
#include <sys/types.h>
#include <sys/wait.h>

#include <err.h>
#include <limits.h>
#include <pwd.h>
#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>

#include <atf-c.h>

/* 10 children each create 10 grandchildren. */
#define TOTAL_CHILDREN          10
#define TOTAL_GRANDCHILDREN     (TOTAL_CHILDREN * TOTAL_CHILDREN)
#define TOTAL_DESCENDENTS       (TOTAL_CHILDREN + TOTAL_GRANDCHILDREN)

#define EXIT_CHILD              66
#define EXIT_GRANDCHILD         76

static void
child(void)
{
       int i, status;
       pid_t pid;

       for (i = 0; i < TOTAL_CHILDREN; i++) {
               ATF_REQUIRE((pid = fork()) != -1);
               if (pid == 0) {
                       /* grandchild */
                       _exit(EXIT_GRANDCHILD);
               }
       }

       for (i = 0; i < TOTAL_CHILDREN; i++) {
               ATF_REQUIRE((pid = wait(&status)) != -1);
       }
       _exit(EXIT_CHILD);
}

ATF_TC(proc4);
ATF_TC_HEAD(proc4, tc)
{
       atf_tc_set_md_var(tc, "descr", "Exercises EVFILT_PROC + NOTE_TRACK");
}

ATF_TC_BODY(proc4, tc)
{
       int total_tracks = 0;
       int child_exits = 0;
       int grandchild_exits = 0;
       pid_t pid;
       int kq, status;
       struct kevent event;
       struct timespec ts = { 0, 0 };
       int i, rv;

       ATF_REQUIRE((kq = kqueue()) >= 0);

       EV_SET(&event, getpid(), EVFILT_PROC, EV_ADD,
           NOTE_TRACK | NOTE_EXIT, 0, 0);

       ATF_REQUIRE(kevent(kq, &event, 1, NULL, 0, NULL) == 0);

       for (i = 0; i < TOTAL_CHILDREN; i++) {
               ATF_REQUIRE((pid = fork()) != -1);
               if (pid == 0) {
                       child();
                       /* NOTREACHED */
               }
       }

       for (;;) {
               if (total_tracks == TOTAL_DESCENDENTS &&
                   child_exits == TOTAL_CHILDREN &&
                   grandchild_exits == TOTAL_GRANDCHILDREN) {
                       break;
               }
               memset(&event, 0, sizeof(event));
               rv = kevent(kq, NULL, 0, &event, 1, NULL);
               ATF_REQUIRE(rv != -1);
               ATF_REQUIRE(rv == 1);
               if (event.fflags & NOTE_CHILD) {
                       total_tracks++;
                       ATF_REQUIRE(total_tracks <= TOTAL_DESCENDENTS);
               } else if (event.fflags & NOTE_EXIT) {
                       ATF_REQUIRE(event.flags & EV_EOF);
                       ATF_REQUIRE(event.data >= 0);
                       ATF_REQUIRE(event.data <= UINT_MAX);
                       status = (int)event.data;
                       ATF_REQUIRE(WIFEXITED(status));
                       ATF_REQUIRE(WEXITSTATUS(status) == EXIT_CHILD ||
                                   WEXITSTATUS(status) == EXIT_GRANDCHILD);
                       if (WEXITSTATUS(status) == EXIT_CHILD) {
                               child_exits++;
                               ATF_REQUIRE(child_exits <= TOTAL_CHILDREN);
                               ATF_REQUIRE(wait4((pid_t)event.ident,
                                                 &status,
                                                 WNOHANG,
                                                 NULL) != -1);
                               ATF_REQUIRE(status == (int)event.data);
                       } else {
                               grandchild_exits++;
                               ATF_REQUIRE(grandchild_exits <=
                                           TOTAL_GRANDCHILDREN);
                       }
               } else {
                       /*
                        * We didn't ask for NOTE_FORK, so we don't
                        * expect to ever see it, even though we are
                        * getting NOTE_CHILD as the result of the
                        * NOTE_TRACK.
                        */
                       ATF_REQUIRE((event.fflags & NOTE_FORK) == 0);

                       /*
                        * Bomb out of we are getting a TRACKERR.
                        * XXX This could legitimately happen if
                        * the kernel is low on memory because the
                        * code path involved specifically chooses
                        * not to block when allocating memory.
                        */
                       ATF_REQUIRE((event.fflags & NOTE_TRACKERR) == 0);
               }
       }

       ATF_REQUIRE(kevent(kq, NULL, 0, &event, 1, &ts) == 0);

       (void)close(kq);
}

ATF_TP_ADD_TCS(tp)
{
       ATF_TP_ADD_TC(tp, proc4);

       return atf_no_error();
}