/*

 * Copyright 2008-2009 Sun Microsystems, Inc.  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.  Sun designates this

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

 * by Sun 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 Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,

 * CA 95054 USA or visit www.sun.com if you need additional information or

 * have any questions.

 */

#include "jni.h"

#include "jni_util.h"

#include "jvm.h"

#include "jlong.h"

#include <stdlib.h>

#include <dlfcn.h>

#include <sys/types.h>

#include <sys/socket.h>

#include <sys/poll.h>

#include "sun_nio_fs_LinuxWatchService.h"

/* inotify.h may not be available at build time */

#ifdef  __cplusplus

extern "C" {

#endif

struct inotify_event

{

  int wd;

  uint32_t mask;

  uint32_t cookie;

  uint32_t len;

  char name __flexarr;

};

#ifdef  __cplusplus

}

#endif

typedef int inotify_init_func(void);

typedef int inotify_add_watch_func(int fd, const char* path, uint32_t mask);

typedef int inotify_rm_watch_func(int fd, uint32_t wd);

inotify_init_func* my_inotify_init_func = NULL;

inotify_add_watch_func* my_inotify_add_watch_func = NULL;

inotify_rm_watch_func* my_inotify_rm_watch_func = NULL;

static void throwUnixException(JNIEnv* env, int errnum) {

    jobject x = JNU_NewObjectByName(env, "sun/nio/fs/UnixException",

        "(I)V", errnum);

    if (x != NULL) {

        (*env)->Throw(env, x);

    }

}

JNIEXPORT void JNICALL

Java_sun_nio_fs_LinuxWatchService_init(JNIEnv *env, jclass clazz)

{

    my_inotify_init_func = (inotify_init_func*)

        dlsym(RTLD_DEFAULT, "inotify_init");

    my_inotify_add_watch_func =

        (inotify_add_watch_func*) dlsym(RTLD_DEFAULT, "inotify_add_watch");

    my_inotify_rm_watch_func =

        (inotify_rm_watch_func*) dlsym(RTLD_DEFAULT, "inotify_rm_watch");

    if ((my_inotify_init_func == NULL) || (my_inotify_add_watch_func == NULL) ||

        (my_inotify_rm_watch_func == NULL)) {

        JNU_ThrowInternalError(env, "unable to get address of inotify functions");

    }

}

JNIEXPORT jint JNICALL

Java_sun_nio_fs_LinuxWatchService_eventSize(JNIEnv *env, jclass clazz)

{

    return (jint)sizeof(struct inotify_event);

}

JNIEXPORT jintArray JNICALL

Java_sun_nio_fs_LinuxWatchService_eventOffsets(JNIEnv *env, jclass clazz)

{

    jintArray result = (*env)->NewIntArray(env, 5);

    if (result != NULL) {

        jint arr[5];

        arr[0] = (jint)offsetof(struct inotify_event, wd);

        arr[1] = (jint)offsetof(struct inotify_event, mask);

        arr[2] = (jint)offsetof(struct inotify_event, cookie);

        arr[3] = (jint)offsetof(struct inotify_event, len);

        arr[4] = (jint)offsetof(struct inotify_event, name);

        (*env)->SetIntArrayRegion(env, result, 0, 5, arr);

    }

    return result;

}

JNIEXPORT jint JNICALL

Java_sun_nio_fs_LinuxWatchService_inotifyInit

    (JNIEnv* env, jclass clazz)

{

    int ifd = (*my_inotify_init_func)();

    if (ifd == -1) {

        throwUnixException(env, errno);

    }

    return (jint)ifd;

}

JNIEXPORT jint JNICALL

Java_sun_nio_fs_LinuxWatchService_inotifyAddWatch

    (JNIEnv* env, jclass clazz, jint fd, jlong address, jint mask)

{

    int wfd = -1;

    const char* path = (const char*)jlong_to_ptr(address);

    wfd = (*my_inotify_add_watch_func)((int)fd, path, mask);

    if (wfd == -1) {

        throwUnixException(env, errno);

    }

    return (jint)wfd;

}

JNIEXPORT void JNICALL

Java_sun_nio_fs_LinuxWatchService_inotifyRmWatch

    (JNIEnv* env, jclass clazz, jint fd, jint wd)

{

    int err = (*my_inotify_rm_watch_func)((int)fd, (int)wd);

    if (err == -1)

        throwUnixException(env, errno);

}

JNIEXPORT void JNICALL

Java_sun_nio_fs_LinuxWatchService_configureBlocking

    (JNIEnv* env, jclass clazz, jint fd, jboolean blocking)

{

    int flags = fcntl(fd, F_GETFL);

    if ((blocking == JNI_FALSE) && !(flags & O_NONBLOCK))

        fcntl(fd, F_SETFL, flags | O_NONBLOCK);

    else if ((blocking == JNI_TRUE) && (flags & O_NONBLOCK))

        fcntl(fd, F_SETFL, flags & ~O_NONBLOCK);

}

JNIEXPORT void JNICALL

Java_sun_nio_fs_LinuxWatchService_socketpair

    (JNIEnv* env, jclass clazz, jintArray sv)

{

    int sp[2];

    if (socketpair(PF_UNIX, SOCK_STREAM, 0, sp) == -1) {

        throwUnixException(env, errno);

    } else {

        jint res[2];

        res[0] = (jint)sp[0];

        res[1] = (jint)sp[1];

        (*env)->SetIntArrayRegion(env, sv, 0, 2, &res[0]);

    }

}

JNIEXPORT jint JNICALL

Java_sun_nio_fs_LinuxWatchService_poll

    (JNIEnv* env, jclass clazz, jint fd1, jint fd2)

{

    struct pollfd ufds[2];

    int n;

    ufds[0].fd = fd1;

    ufds[0].events = POLLIN;

    ufds[1].fd = fd2;

    ufds[1].events = POLLIN;

    n = poll(&ufds[0], 2, -1);

    if (n == -1) {

        if (errno == EINTR) {

            n = 0;

        } else {

            throwUnixException(env, errno);

        }

     }

    return (jint)n;

}