/*

 * 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.

 */

/*

 * KQueueArrayWrapper.c

 * Implementation of Selector using FreeBSD / Mac OS X kqueues

 * Derived from Sun's DevPollArrayWrapper

 */

#include "jni.h"

#include "jni_util.h"

#include "jvm.h"

#include "jlong.h"

#include <sys/types.h>

#include <sys/event.h>

#include <sys/time.h>

JNIEXPORT void JNICALL

Java_sun_nio_ch_KQueueArrayWrapper_initStructSizes(JNIEnv *env, jclass clazz)

{

#define CHECK_EXCEPTION() { \

    if ((*env)->ExceptionCheck(env)) { \

        goto exceptionOccurred; \

    } \

}

#define CHECK_ERROR_AND_EXCEPTION(_field) { \

    if (_field == NULL) { \

        goto badField; \

    } \

    CHECK_EXCEPTION(); \

}

    jfieldID field;

    field = (*env)->GetStaticFieldID(env, clazz, "EVFILT_READ", "S");

    CHECK_ERROR_AND_EXCEPTION(field);

    (*env)->SetStaticShortField(env, clazz, field, EVFILT_READ);

    CHECK_EXCEPTION();

    field = (*env)->GetStaticFieldID(env, clazz, "EVFILT_WRITE", "S");

    CHECK_ERROR_AND_EXCEPTION(field);

    (*env)->SetStaticShortField(env, clazz, field, EVFILT_WRITE);

    CHECK_EXCEPTION();

    field = (*env)->GetStaticFieldID(env, clazz, "SIZEOF_KEVENT", "S");

    CHECK_ERROR_AND_EXCEPTION(field);

    (*env)->SetStaticShortField(env, clazz, field, (short) sizeof(struct kevent));

    CHECK_EXCEPTION();

    field = (*env)->GetStaticFieldID(env, clazz, "FD_OFFSET", "S");

    CHECK_ERROR_AND_EXCEPTION(field);

    (*env)->SetStaticShortField(env, clazz, field, (short) offsetof(struct kevent, ident));

    CHECK_EXCEPTION();

    field = (*env)->GetStaticFieldID(env, clazz, "FILTER_OFFSET", "S");

    CHECK_ERROR_AND_EXCEPTION(field);

    (*env)->SetStaticShortField(env, clazz, field, (short) offsetof(struct kevent, filter));

    CHECK_EXCEPTION();

    return;

badField:

    return;

exceptionOccurred:

    return;

#undef CHECK_EXCEPTION

#undef CHECK_ERROR_AND_EXCEPTION

}

JNIEXPORT jint JNICALL

Java_sun_nio_ch_KQueueArrayWrapper_init(JNIEnv *env, jobject this)

{

    int kq = kqueue();

    if (kq < 0) {

        JNU_ThrowIOExceptionWithLastError(env, "KQueueArrayWrapper: kqueue() failed");

    }

    return kq;

}

JNIEXPORT void JNICALL

Java_sun_nio_ch_KQueueArrayWrapper_register0(JNIEnv *env, jobject this,

                                             jint kq, jint fd, jint r, jint w)

{

    struct kevent changes[2];

    struct kevent errors[2];

    struct timespec dontBlock = {0, 0};

    // if (r) then { register for read } else { unregister for read }

    // if (w) then { register for write } else { unregister for write }

    // Ignore errors - they're probably complaints about deleting non-

    //   added filters - but provide an error array anyway because

    //   kqueue behaves erratically if some of its registrations fail.

    EV_SET(&changes[0], fd, EVFILT_READ,  r ? EV_ADD : EV_DELETE, 0, 0, 0);

    EV_SET(&changes[1], fd, EVFILT_WRITE, w ? EV_ADD : EV_DELETE, 0, 0, 0);

    kevent(kq, changes, 2, errors, 2, &dontBlock);

}

JNIEXPORT jint JNICALL

Java_sun_nio_ch_KQueueArrayWrapper_kevent0(JNIEnv *env, jobject this, jint kq,

                                           jlong kevAddr, jint kevCount,

                                           jlong timeout)

{

    struct kevent *kevs = (struct kevent *)jlong_to_ptr(kevAddr);

    struct timespec ts;

    struct timespec *tsp;

    int result;

    // Java timeout is in milliseconds. Convert to struct timespec.

    // Java timeout == -1 : wait forever : timespec timeout of NULL

    // Java timeout == 0  : return immediately : timespec timeout of zero

    if (timeout >= 0) {

        // For some indeterminate reason kevent(2) has been found to fail with

        // an EINVAL error for timeout values greater than or equal to

        // 100000001000L. To avoid this problem, clamp the timeout arbitrarily

        // to the maximum value of a 32-bit signed integer which is

        // approximately 25 days in milliseconds.

        const jlong timeoutMax = 0x7fffffff; // java.lang.Integer.MAX_VALUE

        if (timeout > timeoutMax) {

            timeout = timeoutMax;

        }

        ts.tv_sec = timeout / 1000;

        ts.tv_nsec = (timeout % 1000) * 1000000; //nanosec = 1 million millisec

        tsp = &ts;

    } else {

        tsp = NULL;

    }

    if (result < 0) {

    }

    return result;

}

JNIEXPORT void JNICALL

Java_sun_nio_ch_KQueueArrayWrapper_interrupt(JNIEnv *env, jclass cls, jint fd)

{

    char c = 1;

    if (1 != write(fd, &c, 1)) {

        JNU_ThrowIOExceptionWithLastError(env, "KQueueArrayWrapper: interrupt failed");

    }

}