/*

 * Copyright (c) 2001, 2013, 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 "io_util.h"

#include "io_util_md.h"

#include <string.h>

#include <unistd.h>

#ifdef __solaris__

#include <sys/filio.h>

#endif

#if defined(__linux__) || defined(_ALLBSD_SOURCE)

#include <sys/ioctl.h>

#endif

#ifdef MACOSX

#include <CoreFoundation/CoreFoundation.h>

__private_extern__

jstring newStringPlatform(JNIEnv *env, const char* str)

{

    jstring rv = NULL;

    CFMutableStringRef csref = CFStringCreateMutable(NULL, 0);

    if (csref == NULL) {

        JNU_ThrowOutOfMemoryError(env, "native heap");

    } else {

        CFStringAppendCString(csref, str, kCFStringEncodingUTF8);

        CFStringNormalize(csref, kCFStringNormalizationFormC);

        int clen = CFStringGetLength(csref);

        int ulen = (clen + 1) * 2;        // utf16 + zero padding

        char* chars = malloc(ulen);

        if (chars == NULL) {

            CFRelease(csref);

            JNU_ThrowOutOfMemoryError(env, "native heap");

        } else {

            if (CFStringGetCString(csref, chars, ulen, kCFStringEncodingUTF16)) {

                rv = (*env)->NewString(env, (jchar*)chars, clen);

            }

            free(chars);

            CFRelease(csref);

        }

    }

    return rv;

}

#endif

FD

handleOpen(const char *path, int oflag, int mode) {

    FD fd;

    RESTARTABLE(open64(path, oflag, mode), fd);

    if (fd != -1) {

        struct stat64 buf64;

        int result;

        RESTARTABLE(fstat64(fd, &buf64), result);

        if (result != -1) {

            if (S_ISDIR(buf64.st_mode)) {

                close(fd);

                errno = EISDIR;

                fd = -1;

            }

        } else {

            close(fd);

            fd = -1;

        }

    }

    return fd;

}

void

fileOpen(JNIEnv *env, jobject this, jstring path, jfieldID fid, int flags)

{

    WITH_PLATFORM_STRING(env, path, ps) {

        FD fd;

#if defined(__linux__) || defined(_ALLBSD_SOURCE)

        /* Remove trailing slashes, since the kernel won't */

        char *p = (char *)ps + strlen(ps) - 1;

        while ((p > ps) && (*p == '/'))

            *p-- = '\0';

#endif

        fd = handleOpen(ps, flags, 0666);

        if (fd != -1) {

            SET_FD(this, fd, fid);

        } else {

            throwFileNotFoundException(env, path);

        }

    } END_PLATFORM_STRING(env, ps);

}

void

fileClose(JNIEnv *env, jobject this, jfieldID fid)

{

    FD fd = GET_FD(this, fid);

    if (fd == -1) {

        return;

    }

    /* Set the fd to -1 before closing it so that the timing window

     * of other threads using the wrong fd (closed but recycled fd,

     * that gets re-opened with some other filename) is reduced.

     * Practically the chance of its occurance is low, however, we are

     * taking extra precaution over here.

     */

    SET_FD(this, -1, fid);

    /*

     * Don't close file descriptors 0, 1, or 2. If we close these stream

     * then a subsequent file open or socket will use them. Instead we

     * just redirect these file descriptors to /dev/null.

     */

    if (fd >= STDIN_FILENO && fd <= STDERR_FILENO) {

        int devnull = open("/dev/null", O_WRONLY);

        if (devnull < 0) {

            SET_FD(this, fd, fid); // restore fd

            JNU_ThrowIOExceptionWithLastError(env, "open /dev/null failed");

        } else {

            dup2(devnull, fd);

            close(devnull);

        }

    } else if (close(fd) == -1) {

        JNU_ThrowIOExceptionWithLastError(env, "close failed");

    }

}

ssize_t

handleRead(FD fd, void *buf, jint len)

{

    ssize_t result;

    RESTARTABLE(read(fd, buf, len), result);

    return result;

}

ssize_t

handleWrite(FD fd, const void *buf, jint len)

{

    ssize_t result;

    RESTARTABLE(write(fd, buf, len), result);

    return result;

}

jint

handleAvailable(FD fd, jlong *pbytes)

{

    int mode;

    struct stat64 buf64;

    jlong size = -1, current = -1;

    int result;

    RESTARTABLE(fstat64(fd, &buf64), result);

    if (result != -1) {

        mode = buf64.st_mode;

        if (S_ISCHR(mode) || S_ISFIFO(mode) || S_ISSOCK(mode)) {

            int n;

            int result;

            RESTARTABLE(ioctl(fd, FIONREAD, &n), result);

            if (result >= 0) {

                *pbytes = n;

                return 1;

            }

        } else if (S_ISREG(mode)) {

            size = buf64.st_size;

        }

    }

    if ((current = lseek64(fd, 0, SEEK_CUR)) == -1) {

        return 0;

    }

    if (size < current) {

        if ((size = lseek64(fd, 0, SEEK_END)) == -1)

            return 0;

        else if (lseek64(fd, current, SEEK_SET) == -1)

            return 0;

    }

}

jint

handleSetLength(FD fd, jlong length)

{

    int result;

    RESTARTABLE(ftruncate64(fd, length), result);

    return result;

}

size_t

getLastErrorString(char *buf, size_t len)

{

    if (errno == 0 || len < 1) return 0;

    const char *err = strerror(errno);

    size_t n = strlen(err);

    if (n >= len)

        n = len - 1;

    strncpy(buf, err, n);

    buf[n] = '\0';

    return n;

}