1 /*
2 * Copyright (c) 1997, 2021, 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 <sys/ioctl.h>
27 #include <sys/types.h>
28 #include <sys/stat.h>
29 #include <fcntl.h>
30 #include <unistd.h>
31 #include <limits.h>
32
33 #include "jni.h"
34 #include "jni_util.h"
35 #include "jlong.h"
36 #include "io_util.h"
37 #include "io_util_md.h"
38
39 #include "jvm.h"
40
41
42 #include "io_util_md.h"
43 #include <nativehelper/JNIHelp.h>
44
45 #define NATIVE_METHOD(className, functionName, signature) \
46 { #functionName, signature, (void*)(className ## _ ## functionName) }
47
48 /*******************************************************************/
49 /* BEGIN JNI ********* BEGIN JNI *********** BEGIN JNI ************/
50 /*******************************************************************/
51
52 jfieldID fis_fd; /* id for jobject 'fd' in java.io.FileInputStream */
53
54 /**************************************************************
55 * Input stream
56 */
57
58
FileInputStream_initIDs(JNIEnv * env)59 static void FileInputStream_initIDs(JNIEnv *env) {
60 jclass clazz = (*env)->FindClass(env, "java/io/FileInputStream");
61 fis_fd = (*env)->GetFieldID(env, clazz, "fd", "Ljava/io/FileDescriptor;");
62 }
63
64 // BEGIN Android-removed: Open files using IoBridge to share BlockGuard & StrictMode logic.
65 // http://b/112107427
66 /*
67 JNIEXPORT void JNICALL
68 Java_java_io_FileInputStream_open0(JNIEnv *env, jobject this, jstring path) {
69 fileOpen(env, this, path, fis_fd, O_RDONLY);
70 }
71 */
72 // END Android-removed: Open files using IoBridge to share BlockGuard & StrictMode logic.
73
74 JNIEXPORT jlong JNICALL
Java_java_io_FileInputStream_length0(JNIEnv * env,jobject this)75 Java_java_io_FileInputStream_length0(JNIEnv *env, jobject this) {
76
77 FD fd;
78 jlong length = jlong_zero;
79
80 fd = getFD(env, this, fis_fd);
81 if (fd == -1) {
82 JNU_ThrowIOException(env, "Stream Closed");
83 return -1;
84 }
85 if ((length = IO_GetLength(fd)) == -1) {
86 JNU_ThrowIOExceptionWithLastError(env, "GetLength failed");
87 }
88 return length;
89 }
90
91 JNIEXPORT jlong JNICALL
Java_java_io_FileInputStream_position0(JNIEnv * env,jobject this)92 Java_java_io_FileInputStream_position0(JNIEnv *env, jobject this) {
93 FD fd;
94 jlong ret;
95
96 fd = getFD(env, this, fis_fd);
97 if (fd == -1) {
98 JNU_ThrowIOException(env, "Stream Closed");
99 return -1;
100 }
101 if ((ret = IO_Lseek(fd, 0L, SEEK_CUR)) == -1) {
102 JNU_ThrowIOExceptionWithLastError(env, "Seek failed");
103 }
104 return ret;
105 }
106
107 JNIEXPORT jlong JNICALL
Java_java_io_FileInputStream_skip0(JNIEnv * env,jobject this,jlong toSkip)108 Java_java_io_FileInputStream_skip0(JNIEnv *env, jobject this, jlong toSkip) {
109 jlong cur = jlong_zero;
110 jlong end = jlong_zero;
111 FD fd = getFD(env, this, fis_fd);
112 if (fd == -1) {
113 JNU_ThrowIOException (env, "Stream Closed");
114 return 0;
115 }
116 if ((cur = IO_Lseek(fd, (jlong)0, (jint)SEEK_CUR)) == -1) {
117 if (errno == ESPIPE) {
118 JNU_ThrowByName(env, "java/io/FileInputStream$UseManualSkipException", NULL);
119 } else {
120 JNU_ThrowIOExceptionWithLastError(env, "Seek error");
121 }
122 } else if ((end = IO_Lseek(fd, toSkip, (jint)SEEK_CUR)) == -1) {
123 JNU_ThrowIOExceptionWithLastError(env, "Seek error");
124 }
125 return (end - cur);
126 }
127
available(int fd,jlong * bytes)128 static int available(int fd, jlong *bytes) {
129 // BEGIN Android-added: Fuchsia does not support FIONREAD. http://b/120566512
130 #if defined(__Fuchsia__)
131 *bytes = 0;
132 return 1;
133 #else
134 // END Android-added: Fuchsia does not support FIONREAD. http://b/120566512
135 int n;
136 // Unlike the original OpenJdk implementation, we use FIONREAD for all file
137 // types. For regular files, this is specified to return the difference
138 // between the current position and the file size. Note that this can be
139 // negative if we're positioned past the end of the file. We must return 0
140 // in that case.
141 if (ioctl(fd, FIONREAD, &n) != -1) {
142 if (n < 0) {
143 n = 0;
144 }
145 *bytes = n;
146 return 1;
147 }
148
149 // FIONREAD is specified to return ENOTTY when fd refers to a file
150 // type for which this ioctl isn't implemented.
151 if (errno == ENOTTY) {
152 *bytes = 0;
153 return 1;
154 }
155
156 // Raise an exception for all other error types.
157 return 0;
158 // Android-added: Fuchsia does not support the FIONREAD code. http://b/120566512
159 #endif
160 }
161
162 JNIEXPORT jint JNICALL
Java_java_io_FileInputStream_available0(JNIEnv * env,jobject this)163 Java_java_io_FileInputStream_available0(JNIEnv *env, jobject this) {
164 jlong ret;
165 FD fd = getFD(env, this, fis_fd);
166 if (fd == -1) {
167 JNU_ThrowIOException (env, "Stream Closed");
168 return 0;
169 }
170 if (available(fd, &ret)) {
171 if (ret > INT_MAX) {
172 ret = (jlong) INT_MAX;
173 } else if (ret < 0) {
174 ret = 0;
175 }
176 return jlong_to_jint(ret);
177 }
178 JNU_ThrowIOExceptionWithLastError(env, NULL);
179 return 0;
180 }
181
182 static JNINativeMethod gMethods[] = {
183 NATIVE_METHOD(Java_java_io_FileInputStream, length0, "()J"),
184 NATIVE_METHOD(Java_java_io_FileInputStream, position0, "()J"),
185 NATIVE_METHOD(Java_java_io_FileInputStream, skip0, "(J)J"),
186 NATIVE_METHOD(Java_java_io_FileInputStream, available0, "()I"),
187 };
188
register_java_io_FileInputStream(JNIEnv * env)189 void register_java_io_FileInputStream(JNIEnv* env) {
190 jniRegisterNativeMethods(env, "java/io/FileInputStream", gMethods, NELEM(gMethods));
191 FileInputStream_initIDs(env);
192 }
193