1 /*

     2  * Copyright (c) 2001, 2014, Oracle and/or its affiliates. All rights reserved.

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

     4  *

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

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

     7  * published by the Free Software Foundation.  Oracle designates this

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

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

    10  *

    11  * This code is distributed in the hope that it will be useful, but WITHOUT

    12  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or

    13  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License

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

    15  * accompanied this code).

    16  *

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

    18  * 2 along with this work; if not, write to the Free Software Foundation,

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

    20  *

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

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

    23  * questions.

    24  */

    25 

    26 /*

    27  * Solaris/Linux platform specific code to support the Prefs API.

    28  */

    29 

    30 #include <unistd.h>

    31 #include <sys/types.h>

    32 #include <sys/stat.h>

    33 #include <fcntl.h>

    34 #include <errno.h>

    35 #include <utime.h>

    36 #include "jni_util.h"

    37 

    38 JNIEXPORT jint JNICALL

    39 Java_java_util_prefs_FileSystemPreferences_chmod(JNIEnv *env,

    40                        jclass thisclass, jstring java_fname, jint permission) {

    41     const char *fname = JNU_GetStringPlatformChars(env, java_fname, NULL);

    42     int result = -1;

    43     if (fname) {

    44         result =  chmod(fname, permission);

    45         if (result != 0)

    46             result = errno;

    47         JNU_ReleaseStringPlatformChars(env, java_fname, fname);

    48     }

    49     return (jint) result;

    50 }

    51 

    52 #if defined(_ALLBSD_SOURCE)

    53 typedef struct flock FLOCK;

    54 #else

    55 typedef struct flock64 FLOCK;

    56 #endif

    57 

    58 /**

    59  * Try to open a named lock file.

    60  * The result is a cookie that can be used later to unlock the file.

    61  * On failure the result is zero.

    62  */

    63 JNIEXPORT jintArray JNICALL

    64 Java_java_util_prefs_FileSystemPreferences_lockFile0(JNIEnv *env,

    65     jclass thisclass, jstring java_fname, jint permission, jboolean shared) {

    66     const char *fname = JNU_GetStringPlatformChars(env, java_fname, NULL);

    67     int fd, rc;

    68     int result[2];

    69     jintArray javaResult = NULL;

    70     int old_umask;

    71     FLOCK fl;

    72 

    73     if (!fname)

    74         return javaResult;

    75 

    76     fl.l_whence = SEEK_SET;

    77     fl.l_len = 0;

    78     fl.l_start = 0;

    79     if (shared == JNI_TRUE) {

    80         fl.l_type = F_RDLCK;

    81     } else {

    82         fl.l_type = F_WRLCK;

    83     }

    84 

    85     if (shared == JNI_TRUE) {

    86         fd = open(fname, O_RDONLY, 0);

    87     } else {

    88         old_umask = umask(0);

    89         fd = open(fname, O_WRONLY|O_CREAT, permission);

    90         result[1] = errno;

    91         umask(old_umask);

    92     }

    93 

    94     if (fd < 0) {

    95         result[0] = 0;

    96     } else {

    97 #if defined(_ALLBSD_SOURCE)

    98         rc = fcntl(fd, F_SETLK, &fl);

    99 #else

   100         rc = fcntl(fd, F_SETLK64, &fl);

   101 #endif

   102         result[1] = errno;

   103         if (rc < 0) {

   104             result[0]= 0;

   105             close(fd);

   106         } else {

   107           result[0] = fd;

   108         }

   109     }

   110     JNU_ReleaseStringPlatformChars(env, java_fname, fname);

   111     javaResult = (*env)->NewIntArray(env,2);

   112     if (javaResult)

   113         (*env)->SetIntArrayRegion(env, javaResult, 0, 2, result);

   114     return javaResult;

   115 }

   116 

   117 

   118 /**

   119  * Try to unlock a lock file, using a cookie returned by lockFile.

   120  */

   121 JNIEXPORT jint JNICALL

   122 Java_java_util_prefs_FileSystemPreferences_unlockFile0(JNIEnv *env,

   123                                       jclass thisclass, jint fd) {

   124 

   125     int rc;

   126     FLOCK fl;

   127     fl.l_whence = SEEK_SET;

   128     fl.l_len = 0;

   129     fl.l_start = 0;

   130     fl.l_type = F_UNLCK;

   131 

   132 #if defined(_ALLBSD_SOURCE)

   133     rc = fcntl(fd, F_SETLK, &fl);

   134 #else

   135     rc = fcntl(fd, F_SETLK64, &fl);

   136 #endif

   137 

   138     if (rc < 0) {

   139         close(fd);

   140         return (jint)errno;

   141     }

   142     rc = close(fd);

   143     if (rc < 0) {

   144         return (jint) errno;

   145     }

   146     return 0;

   147 }