/*

 * Copyright 2000-2007 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 <sys/mman.h>

#include <sys/stat.h>

#include "sun_nio_ch_FileChannelImpl.h"

#include "java_lang_Integer.h"

#include "nio.h"

#include "nio_util.h"

#include <dlfcn.h>

static jfieldID chan_fd;        /* jobject 'fd' in sun.io.FileChannelImpl */

#ifdef __solaris__

typedef struct sendfilevec64 {

    int     sfv_fd;         /* input fd */

    uint_t  sfv_flag;       /* Flags. see below */

    off64_t sfv_off;        /* offset to start reading from */

    size_t  sfv_len;        /* amount of data */

} sendfilevec_t;

/* Function pointer for sendfilev on Solaris 8+ */

typedef ssize_t sendfile_func(int fildes, const struct sendfilevec64 *vec,

                              int sfvcnt, size_t *xferred);

sendfile_func* my_sendfile_func = NULL;

#endif

#ifdef __linux__

#include <sys/sendfile.h>

/* Function pointer for sendfile64 on Linux 2.6 (and newer 2.4 kernels) */

typedef ssize_t sendfile64_func(int out_fd, int in_fd, off64_t *offset, size_t count);

sendfile64_func* my_sendfile64_func = NULL;

#endif

JNIEXPORT jlong JNICALL

Java_sun_nio_ch_FileChannelImpl_initIDs(JNIEnv *env, jclass clazz)

{

    jlong pageSize = sysconf(_SC_PAGESIZE);

    chan_fd = (*env)->GetFieldID(env, clazz, "fd", "Ljava/io/FileDescriptor;");

#ifdef __solaris__

    if (dlopen("/usr/lib/libsendfile.so.1", RTLD_GLOBAL | RTLD_LAZY) != NULL) {

        my_sendfile_func = (sendfile_func*) dlsym(RTLD_DEFAULT, "sendfilev64");

    }

#endif

#ifdef __linux__

    my_sendfile64_func = (sendfile64_func*) dlsym(RTLD_DEFAULT, "sendfile64");

#endif

    return pageSize;

}

static jlong

handle(JNIEnv *env, jlong rv, char *msg)

{

    if (rv >= 0)

        return rv;

    if (errno == EINTR)

        return IOS_INTERRUPTED;

    JNU_ThrowIOExceptionWithLastError(env, msg);

    return IOS_THROWN;

}

JNIEXPORT jlong JNICALL

Java_sun_nio_ch_FileChannelImpl_map0(JNIEnv *env, jobject this,

                                     jint prot, jlong off, jlong len)

{

    void *mapAddress = 0;

    jobject fdo = (*env)->GetObjectField(env, this, chan_fd);

    jint fd = fdval(env, fdo);

    int protections = 0;

    int flags = 0;

    if (prot == sun_nio_ch_FileChannelImpl_MAP_RO) {

        protections = PROT_READ;

        flags = MAP_SHARED;

    } else if (prot == sun_nio_ch_FileChannelImpl_MAP_RW) {

        protections = PROT_WRITE | PROT_READ;

        flags = MAP_SHARED;

    } else if (prot == sun_nio_ch_FileChannelImpl_MAP_PV) {

        protections =  PROT_WRITE | PROT_READ;

        flags = MAP_PRIVATE;

    }

    mapAddress = mmap64(

        0,                    /* Let OS decide location */

        len,                  /* Number of bytes to map */

        protections,          /* File permissions */

        flags,                /* Changes are shared */

        fd,                   /* File descriptor of mapped file */

        off);                 /* Offset into file */

    if (mapAddress == MAP_FAILED) {

        if (errno == ENOMEM) {

            JNU_ThrowOutOfMemoryError(env, "Map failed");

            return IOS_THROWN;

        }

        return handle(env, -1, "Map failed");

    }

    return ((jlong) (unsigned long) mapAddress);

}

JNIEXPORT jint JNICALL

Java_sun_nio_ch_FileChannelImpl_unmap0(JNIEnv *env, jobject this,

                                       jlong address, jlong len)

{

    void *a = (void *)jlong_to_ptr(address);

    return handle(env,

                  munmap(a, (size_t)len),

                  "Unmap failed");

}

JNIEXPORT jint JNICALL

Java_sun_nio_ch_FileChannelImpl_truncate0(JNIEnv *env, jobject this,

                                          jobject fdo, jlong size)

{

    return handle(env,

                  ftruncate64(fdval(env, fdo), size),

                  "Truncation failed");

}

JNIEXPORT jint JNICALL

Java_sun_nio_ch_FileChannelImpl_force0(JNIEnv *env, jobject this,

                                       jobject fdo, jboolean md)

{

    jint fd = fdval(env, fdo);

    int result = 0;

    if (md == JNI_FALSE) {

        result = fdatasync(fd);

    } else {

        result = fsync(fd);

    }

    return handle(env, result, "Force failed");

}

JNIEXPORT jlong JNICALL

Java_sun_nio_ch_FileChannelImpl_position0(JNIEnv *env, jobject this,

                                          jobject fdo, jlong offset)

{

    jint fd = fdval(env, fdo);

    jlong result = 0;

    if (offset < 0) {

        result = lseek64(fd, 0, SEEK_CUR);

    } else {

        result = lseek64(fd, offset, SEEK_SET);

    }

    return handle(env, result, "Position failed");

}

JNIEXPORT jlong JNICALL

Java_sun_nio_ch_FileChannelImpl_size0(JNIEnv *env, jobject this, jobject fdo)

{

    struct stat64 fbuf;

    if (fstat64(fdval(env, fdo), &fbuf) < 0)

        return handle(env, -1, "Size failed");

    return fbuf.st_size;

}

JNIEXPORT void JNICALL

Java_sun_nio_ch_FileChannelImpl_close0(JNIEnv *env, jobject this, jobject fdo)

{

    jint fd = fdval(env, fdo);

    if (fd != -1) {

        jlong result = close(fd);

        if (result < 0) {

            JNU_ThrowIOExceptionWithLastError(env, "Close failed");

        }

    }

}

JNIEXPORT jlong JNICALL

Java_sun_nio_ch_FileChannelImpl_transferTo0(JNIEnv *env, jobject this,

                                            jint srcFD,

                                            jlong position, jlong count,

                                            jint dstFD)

{

#ifdef __linux__

    jlong max = (jlong)java_lang_Integer_MAX_VALUE;

    jlong n;

    if (my_sendfile64_func == NULL) {

        off_t offset;

        if (position > max)

            return IOS_UNSUPPORTED_CASE;

        if (count > max)

            count = max;

        offset = (off_t)position;

        n = sendfile(dstFD, srcFD, &offset, (size_t)count);

    } else {

        off64_t offset = (off64_t)position;

        n = (*my_sendfile64_func)(dstFD, srcFD, &offset, (size_t)count);

    }

    if (n < 0) {

        if (errno == EAGAIN)

            return IOS_UNAVAILABLE;

        if ((errno == EINVAL) && ((ssize_t)count >= 0))

            return IOS_UNSUPPORTED_CASE;

        if (errno == EINTR) {

            return IOS_INTERRUPTED;

        }

        JNU_ThrowIOExceptionWithLastError(env, "Transfer failed");

        return IOS_THROWN;

    }

    return n;

#endif

#ifdef __solaris__

    if (my_sendfile_func == NULL) {

        return IOS_UNSUPPORTED;

    } else {

        sendfilevec_t sfv;

        size_t numBytes = 0;

        jlong result;

        sfv.sfv_fd = srcFD;

        sfv.sfv_flag = 0;

        sfv.sfv_off = (off64_t)position;

        sfv.sfv_len = count;

        result = (*my_sendfile_func)(dstFD, &sfv, 1, &numBytes);

        /* Solaris sendfilev() will return -1 even if some bytes have been

         * transferred, so we check numBytes first.

         */

        if (numBytes > 0)

            return numBytes;

        if (result < 0) {

            if (errno == EAGAIN)

                return IOS_UNAVAILABLE;

            if ((errno == EINVAL) && ((ssize_t)count >= 0))

                return IOS_UNSUPPORTED_CASE;

            if (errno == EINTR)

                return IOS_INTERRUPTED;

            JNU_ThrowIOExceptionWithLastError(env, "Transfer failed");

            return IOS_THROWN;

        }

        return result;

    }

#endif

}

JNIEXPORT jint JNICALL

Java_sun_nio_ch_FileChannelImpl_lock0(JNIEnv *env, jobject this, jobject fdo,

                                      jboolean block, jlong pos, jlong size,

                                      jboolean shared)

{

    jint fd = fdval(env, fdo);

    jint lockResult = 0;

    int cmd = 0;

    struct flock64 fl;

    fl.l_whence = SEEK_SET;

    fl.l_len = (off64_t)size;

    fl.l_start = (off64_t)pos;

    if (shared == JNI_TRUE) {

        fl.l_type = F_RDLCK;

    } else {

        fl.l_type = F_WRLCK;

    }

    if (block == JNI_TRUE) {

        cmd = F_SETLKW64;

    } else {

        cmd = F_SETLK64;

    }

    lockResult = fcntl(fd, cmd, &fl);

    if (lockResult < 0) {

        if ((cmd == F_SETLK64) && (errno == EAGAIN))

            return sun_nio_ch_FileChannelImpl_NO_LOCK;

        if (errno == EINTR)

            return sun_nio_ch_FileChannelImpl_INTERRUPTED;

        JNU_ThrowIOExceptionWithLastError(env, "Lock failed");

    }

    return 0;

}

JNIEXPORT void JNICALL

Java_sun_nio_ch_FileChannelImpl_release0(JNIEnv *env, jobject this,

                                         jobject fdo, jlong pos, jlong size)

{

    jint fd = fdval(env, fdo);

    jint lockResult = 0;

    struct flock64 fl;

    int cmd = F_SETLK64;

    fl.l_whence = SEEK_SET;

    fl.l_len = (off64_t)size;

    fl.l_start = (off64_t)pos;

    fl.l_type = F_UNLCK;

    lockResult = fcntl(fd, cmd, &fl);

    if (lockResult < 0) {

        JNU_ThrowIOExceptionWithLastError(env, "Release failed");

    }

}