/*
 * Copyright (c) 2014 SUSE Linux.  All Rights Reserved.
 *
 * This program is free software; you can redistribute it and/or modify it
 * under the terms of version 2 of the GNU General Public License as
 * published by the Free Software Foundation.
 *
 * This program is distributed in the hope that it would be useful, but
 * WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
 *
 * Further, this software is distributed without any warranty that it is
 * free of the rightful claim of any third person regarding infringement
 * or the like.  Any license provided herein, whether implied or
 * otherwise, applies only to this software file.  Patent licenses, if
 * any, provided herein do not apply to combinations of this program with
 * other software, or any other product whatsoever.
 *
 * Started by Jan Kara <jack@suse.cz>
 *
 * DESCRIPTION
 *     Check that fanotify overflow event is properly generated
 *
 * ALGORITHM
 *     Generate enough events without reading them and check that overflow
 *     event is generated.
 */
#include "config.h"

#include <stdio.h>
#include <sys/stat.h>
#include <sys/types.h>
#include <sys/fcntl.h>
#include <errno.h>
#include <string.h>
#include <sys/syscall.h>
#include "test.h"
#include "linux_syscall_numbers.h"
#include "fanotify.h"
#include "safe_macros.h"

char *TCID = "fanotify05";
int TST_TOTAL = 1;

#if defined(HAVE_SYS_FANOTIFY_H)
#include <sys/fanotify.h>

/* Currently this is fixed in kernel... */
#define MAX_EVENTS 16384

static void setup(void);
static void cleanup(void);

#define BUF_SIZE 256
static char fname[BUF_SIZE];
static int fd, fd_notify;

struct fanotify_event_metadata event;

int main(int ac, char **av)
{
	int lc, i;
	const char *msg;
	int len;

	msg = parse_opts(ac, av, NULL, NULL);
	if (msg != NULL)
		tst_brkm(TBROK, NULL, "OPTION PARSING ERROR - %s", msg);

	setup();

	for (lc = 0; TEST_LOOPING(lc); lc++) {
		/*
		 * generate events
		 */
		for (i = 0; i < MAX_EVENTS + 1; i++) {
			sprintf(fname, "fname_%d", i);
			fd = SAFE_OPEN(cleanup, fname, O_RDWR | O_CREAT, 0644);
			SAFE_CLOSE(cleanup, fd);
		}

		while (1) {
			/*
			 * get list on events
			 */
			len = read(fd_notify, &event, sizeof(event));
			if (len < 0) {
				if (errno == -EAGAIN) {
					tst_resm(TFAIL, "Overflow event not "
						 "generated!\n");
					break;
				}
				tst_brkm(TBROK | TERRNO, cleanup,
					 "read of notification event failed");
				break;
			}
			if (event.fd != FAN_NOFD)
				close(event.fd);

			/*
			 * check events
			 */
			if (event.mask != FAN_OPEN &&
			    event.mask != FAN_Q_OVERFLOW) {
				tst_resm(TFAIL,
					 "get event: mask=%llx (expected %llx)"
					 "pid=%u fd=%d",
					 (unsigned long long)event.mask,
					 (unsigned long long)FAN_OPEN,
					 (unsigned)event.pid, event.fd);
				break;
			}
			if (event.mask == FAN_Q_OVERFLOW) {
				if (event.fd != FAN_NOFD) {
					tst_resm(TFAIL,
						 "invalid overflow event: "
						 "mask=%llx pid=%u fd=%d",
						 (unsigned long long)event.mask,
						 (unsigned)event.pid,
						 event.fd);
					break;
				}
				tst_resm(TPASS,
					 "get event: mask=%llx pid=%u fd=%d",
					 (unsigned long long)event.mask,
					 (unsigned)event.pid, event.fd);
					break;
			}
		}
	}

	cleanup();
	tst_exit();
}

static void setup(void)
{
	tst_sig(NOFORK, DEF_HANDLER, cleanup);

	TEST_PAUSE;

	tst_tmpdir();

	fd_notify = fanotify_init(FAN_CLASS_NOTIF | FAN_NONBLOCK, O_RDONLY);
	if (fd_notify < 0) {
		if (errno == ENOSYS) {
			tst_brkm(TCONF, cleanup,
				 "fanotify is not configured in this kernel.");
		} else {
			tst_brkm(TBROK | TERRNO, cleanup,
				 "fanotify_init failed");
		}
	}

	if (fanotify_mark(fd_notify, FAN_MARK_MOUNT | FAN_MARK_ADD, FAN_OPEN,
			    AT_FDCWD, ".") < 0) {
		tst_brkm(TBROK | TERRNO, cleanup,
			 "fanotify_mark (%d, FAN_MARK_MOUNT | FAN_MARK_ADD, "
			 "FAN_OPEN, AT_FDCWD, \".\") failed",
			 fd_notify);
	}
}

static void cleanup(void)
{
	if (fd_notify > 0 && close(fd_notify) == -1)
		tst_resm(TWARN, "close(%d) failed", fd_notify);

	tst_rmdir();
}

#else

int main(void)
{
	tst_brkm(TCONF, NULL, "system doesn't have required fanotify support");
}

#endif