/*

 * Copyright (c) 2001, 2005, Oracle and/or its affiliates. All rights reserved.

 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.

 *

 * This code is free software; you can redistribute it and/or modify it

 * under the terms of the GNU General Public License version 2 only, as

 * published by the Free Software Foundation.  Oracle designates this

 * particular file as subject to the "Classpath" exception as provided

 * by Oracle in the LICENSE file that accompanied this code.

 *

 * This code 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

 * version 2 for more details (a copy is included in the LICENSE file that

 * accompanied this code).

 *

 * You should have received a copy of the GNU General Public License version

 * 2 along with this work; if not, write to the Free Software Foundation,

 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.

 *

 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA

 * or visit www.oracle.com if you need additional information or have any

 * questions.

 */

#include "jni.h"

#include "jni_util.h"

#include "jvm.h"

#include "jlong.h"

#include "sun_nio_ch_PollArrayWrapper.h"

#include <poll.h>

#include <unistd.h>

#include <sys/time.h>

#define RESTARTABLE(_cmd, _result) do { \

  do { \

    _result = _cmd; \

  } while((_result == -1) && (errno == EINTR)); \

} while(0)

static int

ipoll(struct pollfd fds[], unsigned int nfds, int timeout)

{

    jlong start, now;

    int remaining = timeout;

    struct timeval t;

    int diff;

    gettimeofday(&t, NULL);

    start = t.tv_sec * 1000 + t.tv_usec / 1000;

    for (;;) {

        int res = poll(fds, nfds, remaining);

        if (res < 0 && errno == EINTR) {

            if (remaining >= 0) {

                gettimeofday(&t, NULL);

                now = t.tv_sec * 1000 + t.tv_usec / 1000;

                diff = now - start;

                remaining -= diff;

                if (diff < 0 || remaining <= 0) {

                    return 0;

                }

                start = now;

            }

        } else {

            return res;

        }

    }

}

JNIEXPORT jint JNICALL

Java_sun_nio_ch_PollArrayWrapper_poll0(JNIEnv *env, jobject this,

                                       jlong address, jint numfds,

                                       jlong timeout)

{

    struct pollfd *a;

    int err = 0;

    a = (struct pollfd *) jlong_to_ptr(address);

    if (timeout <= 0) {           /* Indefinite or no wait */

        RESTARTABLE (poll(a, numfds, timeout), err);

    } else {                     /* Bounded wait; bounded restarts */

        err = ipoll(a, numfds, timeout);

    }

    if (err < 0) {

        JNU_ThrowIOExceptionWithLastError(env, "Poll failed");

    }

    return (jint)err;

}

JNIEXPORT void JNICALL

Java_sun_nio_ch_PollArrayWrapper_interrupt(JNIEnv *env, jobject this, jint fd)

{

    int fakebuf[1];

    fakebuf[0] = 1;

    if (write(fd, fakebuf, 1) < 0) {

         JNU_ThrowIOExceptionWithLastError(env,

                                          "Write to interrupt fd failed");

    }

}