1 /* 2 * Copyright (c) 2001, 2010, 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 #include "jni.h" 27 #include "jni_util.h" 28 #include "jvm.h" 29 #include "io_util.h" 30 #include "io_util_md.h" 31 #include <string.h> 32 33 void 34 fileOpen(JNIEnv *env, jobject this, jstring path, jfieldID fid, int flags) 35 { 36 WITH_PLATFORM_STRING(env, path, ps) { 37 FD fd; 38 39 #ifdef __linux__ 40 /* Remove trailing slashes, since the kernel won't */ 41 char *p = (char *)ps + strlen(ps) - 1; 42 while ((p > ps) && (*p == '/')) 43 *p-- = '\0'; 44 #endif 45 fd = JVM_Open(ps, flags, 0666); 46 if (fd >= 0) { 47 SET_FD(this, fd, fid); 48 } else { 49 throwFileNotFoundException(env, path); 50 } 51 } END_PLATFORM_STRING(env, ps); 52 } 53 54 55 void 56 fileClose(JNIEnv *env, jobject this, jfieldID fid) 57 { 58 FD fd = GET_FD(this, fid); 59 if (fd == -1) { 60 return; 61 } 62 63 /* Set the fd to -1 before closing it so that the timing window 64 * of other threads using the wrong fd (closed but recycled fd, 65 * that gets re-opened with some other filename) is reduced. 66 * Practically the chance of its occurance is low, however, we are 67 * taking extra precaution over here. 68 */ 69 SET_FD(this, -1, fid); 70 71 /* 72 * Don't close file descriptors 0, 1, or 2. If we close these stream 73 * then a subsequent file open or socket will use them. Instead we 74 * just redirect these file descriptors to /dev/null. 75 */ 76 if (fd >= STDIN_FILENO && fd <= STDERR_FILENO) { 77 int devnull = open("/dev/null", O_WRONLY); 78 if (devnull < 0) { 79 SET_FD(this, fd, fid); // restore fd 80 JNU_ThrowIOExceptionWithLastError(env, "open /dev/null failed"); 81 } else { 82 dup2(devnull, fd); 83 close(devnull); 84 } 85 } else if (JVM_Close(fd) == -1) { 86 JNU_ThrowIOExceptionWithLastError(env, "close failed"); 87 } 88 }