1 /*
2 * Copyright (c) 1997, 2007, 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 "jni.h"
32 #include "jni_util.h"
33 #include "jlong.h"
34 #include "io_util.h"
35 #include "io_util_md.h"
36
37 #include "jvm.h"
38
39
40 #include <fcntl.h>
41 #include <limits.h>
42
43 #include "io_util_md.h"
44 #include "JNIHelp.h"
45
46 #define NATIVE_METHOD(className, functionName, signature) \
47 { #functionName, signature, (void*)(className ## _ ## functionName) }
48
49 /*******************************************************************/
50 /* BEGIN JNI ********* BEGIN JNI *********** BEGIN JNI ************/
51 /*******************************************************************/
52
53 jfieldID fis_fd; /* id for jobject 'fd' in java.io.FileInputStream */
54
55 /**************************************************************
56 * Input stream
57 */
58
59
FileInputStream_initIDs(JNIEnv * env)60 static void FileInputStream_initIDs(JNIEnv *env) {
61 jclass clazz = (*env)->FindClass(env, "java/io/FileInputStream");
62 fis_fd = (*env)->GetFieldID(env, clazz, "fd", "Ljava/io/FileDescriptor;");
63 }
64
65 JNIEXPORT void JNICALL
FileInputStream_open(JNIEnv * env,jobject this,jstring path)66 FileInputStream_open(JNIEnv *env, jobject this, jstring path) {
67 fileOpen(env, this, path, fis_fd, O_RDONLY);
68 }
69
70 JNIEXPORT jlong JNICALL
FileInputStream_skip0(JNIEnv * env,jobject this,jlong toSkip)71 FileInputStream_skip0(JNIEnv *env, jobject this, jlong toSkip) {
72 jlong cur = jlong_zero;
73 jlong end = jlong_zero;
74 FD fd = GET_FD(this, fis_fd);
75 if (fd == -1) {
76 JNU_ThrowIOException (env, "Stream Closed");
77 return 0;
78 }
79 if ((cur = IO_Lseek(fd, (jlong)0, (jint)SEEK_CUR)) == -1) {
80 if (errno == ESPIPE) {
81 JNU_ThrowByName(env, "java/io/FileInputStream$UseManualSkipException", NULL);
82 } else {
83 JNU_ThrowIOExceptionWithLastError(env, "Seek error");
84 }
85 } else if ((end = IO_Lseek(fd, toSkip, (jint)SEEK_CUR)) == -1) {
86 JNU_ThrowIOExceptionWithLastError(env, "Seek error");
87 }
88 return (end - cur);
89 }
90
available(int fd,jlong * bytes)91 static int available(int fd, jlong *bytes) {
92 int n;
93 // Unlike the original OpenJdk implementation, we use FIONREAD for all file
94 // types. For regular files, this is specified to return the difference
95 // between the current position and the file size. Note that this can be
96 // negative if we're positioned past the end of the file. We must return 0
97 // in that case.
98 if (ioctl(fd, FIONREAD, &n) != -1) {
99 if (n < 0) {
100 n = 0;
101 }
102 *bytes = n;
103 return 1;
104 }
105
106 // FIONREAD is specified to return ENOTTY when fd refers to a file
107 // type for which this ioctl isn't implemented.
108 if (errno == ENOTTY) {
109 *bytes = 0;
110 return 1;
111 }
112
113 // Raise an exception for all other error types.
114 return 0;
115 }
116
117 JNIEXPORT jint JNICALL
FileInputStream_available0(JNIEnv * env,jobject this)118 FileInputStream_available0(JNIEnv *env, jobject this) {
119 jlong ret;
120 FD fd = GET_FD(this, fis_fd);
121 if (fd == -1) {
122 JNU_ThrowIOException (env, "Stream Closed");
123 return 0;
124 }
125 if (available(fd, &ret)) {
126 if (ret > INT_MAX) {
127 ret = (jlong) INT_MAX;
128 }
129 return jlong_to_jint(ret);
130 }
131 JNU_ThrowIOExceptionWithLastError(env, NULL);
132 return 0;
133 }
134
135 static JNINativeMethod gMethods[] = {
136 NATIVE_METHOD(FileInputStream, open, "(Ljava/lang/String;)V"),
137 NATIVE_METHOD(FileInputStream, skip0, "(J)J"),
138 NATIVE_METHOD(FileInputStream, available0, "()I"),
139 };
140
register_java_io_FileInputStream(JNIEnv * env)141 void register_java_io_FileInputStream(JNIEnv* env) {
142 jniRegisterNativeMethods(env, "java/io/FileInputStream", gMethods, NELEM(gMethods));
143 FileInputStream_initIDs(env);
144 }
145