1 /* 2 * Copyright (c) 2001, 2016, 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 #include "jni.h" 26 #include "jni_util.h" 27 #include "jvm.h" 28 #include "io_util.h" 29 #include "io_util_md.h" 30 #include <string.h> 31 #include <unistd.h> 32 33 #ifdef __solaris__ 34 #include <sys/filio.h> 35 #endif 36 37 #if defined(__linux__) || defined(_ALLBSD_SOURCE) || defined(_AIX) 38 #include <sys/ioctl.h> 39 #endif 40 41 #ifdef MACOSX 42 43 #include <CoreFoundation/CoreFoundation.h> 44 45 __private_extern__ 46 jstring newStringPlatform(JNIEnv *env, const char* str) 47 { 48 jstring rv = NULL; 49 CFMutableStringRef csref = CFStringCreateMutable(NULL, 0); 50 if (csref == NULL) { 51 JNU_ThrowOutOfMemoryError(env, "native heap"); 52 } else { 53 CFStringAppendCString(csref, str, kCFStringEncodingUTF8); 54 CFStringNormalize(csref, kCFStringNormalizationFormC); 55 int clen = CFStringGetLength(csref); 56 int ulen = (clen + 1) * 2; // utf16 + zero padding 57 char* chars = malloc(ulen); 58 if (chars == NULL) { 59 CFRelease(csref); 60 JNU_ThrowOutOfMemoryError(env, "native heap"); 61 } else { 62 if (CFStringGetCString(csref, chars, ulen, kCFStringEncodingUTF16)) { 63 rv = (*env)->NewString(env, (jchar*)chars, clen); 64 } 65 free(chars); 66 CFRelease(csref); 67 } 68 } 69 return rv; 70 } 71 #endif 72 73 FD 74 handleOpen(const char *path, int oflag, int mode) { 75 FD fd; 76 RESTARTABLE(open64(path, oflag, mode), fd); 77 if (fd != -1) { 78 struct stat64 buf64; 79 int result; 80 RESTARTABLE(fstat64(fd, &buf64), result); 81 if (result != -1) { 82 if (S_ISDIR(buf64.st_mode)) { 83 close(fd); 84 errno = EISDIR; 85 fd = -1; 86 } 87 } else { 88 close(fd); 89 fd = -1; 90 } 91 } 92 return fd; 93 } 94 95 void 96 fileOpen(JNIEnv *env, jobject this, jstring path, jfieldID fid, int flags) 97 { 98 WITH_PLATFORM_STRING(env, path, ps) { 99 FD fd; 100 101 #if defined(__linux__) || defined(_ALLBSD_SOURCE) 102 /* Remove trailing slashes, since the kernel won't */ 103 char *p = (char *)ps + strlen(ps) - 1; 104 while ((p > ps) && (*p == '/')) 105 *p-- = '\0'; 106 #endif 107 fd = handleOpen(ps, flags, 0666); 108 if (fd != -1) { 109 jobject fdobj; 110 jboolean append; 111 SET_FD(this, fd, fid); 112 113 fdobj = (*env)->GetObjectField(env, this, fid); 114 if (fdobj != NULL) { 115 append = (flags & O_APPEND) == 0 ? JNI_FALSE : JNI_TRUE; 116 (*env)->SetBooleanField(env, fdobj, IO_append_fdID, append); 117 } 118 } else { 119 throwFileNotFoundException(env, path); 120 } 121 } END_PLATFORM_STRING(env, ps); 122 } 123 124 void 125 fileClose(JNIEnv *env, jobject this, jfieldID fid) 126 { 127 FD fd = GET_FD(this, fid); 128 if (fd == -1) { 129 return; 130 } 131 132 /* Set the fd to -1 before closing it so that the timing window 133 * of other threads using the wrong fd (closed but recycled fd, 134 * that gets re-opened with some other filename) is reduced. 135 * Practically the chance of its occurance is low, however, we are 136 * taking extra precaution over here. 137 */ 138 SET_FD(this, -1, fid); 139 140 /* 141 * Don't close file descriptors 0, 1, or 2. If we close these stream 142 * then a subsequent file open or socket will use them. Instead we 143 * just redirect these file descriptors to /dev/null. 144 */ 145 if (fd >= STDIN_FILENO && fd <= STDERR_FILENO) { 146 int devnull = open("/dev/null", O_WRONLY); 147 if (devnull < 0) { 148 SET_FD(this, fd, fid); // restore fd 149 JNU_ThrowIOExceptionWithLastError(env, "open /dev/null failed"); 150 } else { 151 dup2(devnull, fd); 152 close(devnull); 153 } 154 } else if (close(fd) == -1) { 155 JNU_ThrowIOExceptionWithLastError(env, "close failed"); 156 } 157 } 158 159 ssize_t 160 handleRead(FD fd, void *buf, jint len) 161 { 162 ssize_t result; 163 RESTARTABLE(read(fd, buf, len), result); 164 return result; 165 } 166 167 ssize_t 168 handleWrite(FD fd, const void *buf, jint len) 169 { 170 ssize_t result; 171 RESTARTABLE(write(fd, buf, len), result); 172 return result; 173 } 174 175 jint 176 handleAvailable(FD fd, jlong *pbytes) 177 { 178 int mode; 179 struct stat64 buf64; 180 jlong size = -1, current = -1; 181 182 int result; 183 RESTARTABLE(fstat64(fd, &buf64), result); 184 if (result != -1) { 185 mode = buf64.st_mode; 186 if (S_ISCHR(mode) || S_ISFIFO(mode) || S_ISSOCK(mode)) { 187 int n; 188 int result; 189 RESTARTABLE(ioctl(fd, FIONREAD, &n), result); 190 if (result >= 0) { 191 *pbytes = n; 192 return 1; 193 } 194 } else if (S_ISREG(mode)) { 195 size = buf64.st_size; 196 } 197 } 198 199 if ((current = lseek64(fd, 0, SEEK_CUR)) == -1) { 200 return 0; 201 } 202 203 if (size < current) { 204 if ((size = lseek64(fd, 0, SEEK_END)) == -1) 205 return 0; 206 else if (lseek64(fd, current, SEEK_SET) == -1) 207 return 0; 208 } 209 210 *pbytes = size - current; 211 return 1; 212 } 213 214 jint 215 handleSetLength(FD fd, jlong length) 216 { 217 int result; 218 #if defined(__linux__) 219 /* 220 * On Linux, if the file size is being increased, then ftruncate64() 221 * will modify the metadata value of the size without actually allocating 222 * any blocks which can cause a SIGBUS error if the file is subsequently 223 * memory-mapped. 224 */ 225 struct stat64 sb; 226 227 if (fstat64(fd, &sb) == 0 && length > sb.st_blocks*512) { 228 RESTARTABLE(fallocate64(fd, 0, 0, length), result); 229 return result; 230 } 231 #endif 232 RESTARTABLE(ftruncate64(fd, length), result); 233 return result; 234 } 235 236 jlong 237 handleGetLength(FD fd) 238 { 239 struct stat64 sb; 240 if (fstat64(fd, &sb) == 0) { 241 return sb.st_size; 242 } else { 243 return -1; 244 } 245 }