Home | History | Annotate | Download | only in native 
      1 /*
      2  * Copyright (c) 2001, 2004, 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 #include "JNIHelp.h"
     39 
     40 #define NATIVE_METHOD(className, functionName, signature) \
     41 { #functionName, signature, (void*)(Java_java_util_prefs_ ## className ## _ ## functionName) }
     42 
     43 JNIEXPORT jint JNICALL
     44 Java_java_util_prefs_FileSystemPreferences_chmod(JNIEnv *env,
     45                        jclass thisclass, jstring java_fname, jint permission) {
     46     const char *fname = JNU_GetStringPlatformChars(env, java_fname, JNI_FALSE);
     47     int result;
     48     result =  chmod(fname, permission);
     49     if (result != 0)
     50        result = errno;
     51     JNU_ReleaseStringPlatformChars(env, java_fname, fname);
     52     return (jint) result;
     53 }
     54 
     55 #if defined(_ALLBSD_SOURCE)
     56 typedef struct flock FLOCK;
     57 #else
     58 typedef struct flock64 FLOCK;
     59 #endif
     60 
     61 /**
     62  * Try to open a named lock file.
     63  * The result is a cookie that can be used later to unlock the file.
     64  * On failure the result is zero.
     65  */
     66 JNIEXPORT jintArray JNICALL
     67 Java_java_util_prefs_FileSystemPreferences_lockFile0(JNIEnv *env,
     68     jclass thisclass, jstring java_fname, jint permission, jboolean shared) {
     69     const char *fname = JNU_GetStringPlatformChars(env, java_fname, JNI_FALSE);
     70     int fd, rc;
     71     int result[2];
     72     jintArray javaResult;
     73     int old_umask;
     74     FLOCK fl;
     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     (*env)->SetIntArrayRegion(env, javaResult, 0, 2, result);
    113     return javaResult;
    114 }
    115 
    116 
    117 /**
    118  * Try to unlock a lock file, using a cookie returned by lockFile.
    119  */
    120 JNIEXPORT jint JNICALL
    121 Java_java_util_prefs_FileSystemPreferences_unlockFile0(JNIEnv *env,
    122                                       jclass thisclass, jint fd) {
    123 
    124     int rc;
    125     FLOCK fl;
    126     fl.l_whence = SEEK_SET;
    127     fl.l_len = 0;
    128     fl.l_start = 0;
    129     fl.l_type = F_UNLCK;
    130 
    131 #if defined(_ALLBSD_SOURCE)
    132     rc = fcntl(fd, F_SETLK, &fl);
    133 #else
    134     rc = fcntl(fd, F_SETLK64, &fl);
    135 #endif
    136 
    137     if (rc < 0) {
    138         close(fd);
    139         return (jint)errno;
    140     }
    141     rc = close(fd);
    142     if (rc < 0) {
    143         return (jint) errno;
    144     }
    145     return 0;
    146 }
    147 
    148 static JNINativeMethod gMethods[] = {
    149     NATIVE_METHOD(FileSystemPreferences, lockFile0, "(Ljava/lang/String;IZ)[I"),
    150     NATIVE_METHOD(FileSystemPreferences, unlockFile0, "(I)I"),
    151     NATIVE_METHOD(FileSystemPreferences, chmod, "(Ljava/lang/String;I)I"),
    152 };
    153 
    154 void register_java_util_prefs_FileSystemPreferences(JNIEnv* env) {
    155     jniRegisterNativeMethods(env, "java/util/prefs/FileSystemPreferences", gMethods, NELEM(gMethods));
    156 }
    157