FileInputStream.c revision 50164c3602af46021e434ff5047352299a36e0f0 
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#include "java_io_FileInputStream.h"
40
41#include <fcntl.h>
42#include <limits.h>
43
44#include "io_util_md.h"
45#include "JNIHelp.h"
46
47#define NATIVE_METHOD(className, functionName, signature) \
48{ #functionName, signature, (void*)(className ## _ ## functionName) }
49
50/*******************************************************************/
51/*  BEGIN JNI ********* BEGIN JNI *********** BEGIN JNI ************/
52/*******************************************************************/
53
54jfieldID fis_fd; /* id for jobject 'fd' in java.io.FileInputStream */
55
56/**************************************************************
57 * static methods to store field ID's in initializers
58 */
59
60JNIEXPORT void JNICALL
61FileInputStream_initIDs(JNIEnv *env, jclass fdClass) {
62    fis_fd = (*env)->GetFieldID(env, fdClass, "fd", "Ljava/io/FileDescriptor;");
63}
64
65/**************************************************************
66 * Input stream
67 */
68
69JNIEXPORT void JNICALL
70FileInputStream_open(JNIEnv *env, jobject this, jstring path) {
71    fileOpen(env, this, path, fis_fd, O_RDONLY);
72}
73
74JNIEXPORT jint JNICALL
75FileInputStream_read0(JNIEnv *env, jobject this) {
76    return readSingle(env, this, fis_fd);
77}
78
79JNIEXPORT jint JNICALL
80FileInputStream_readBytes(JNIEnv *env, jobject this,
81        jbyteArray bytes, jint off, jint len) {
82    return readBytes(env, this, bytes, off, len, fis_fd);
83}
84
85JNIEXPORT jlong JNICALL
86FileInputStream_skip0(JNIEnv *env, jobject this, jlong toSkip) {
87    jlong cur = jlong_zero;
88    jlong end = jlong_zero;
89    FD fd = GET_FD(this, fis_fd);
90    if (fd == -1) {
91        JNU_ThrowIOException (env, "Stream Closed");
92        return 0;
93    }
94    if ((cur = IO_Lseek(fd, (jlong)0, (jint)SEEK_CUR)) == -1) {
95      if (errno == ESPIPE) {
96        JNU_ThrowByName(env, "java/io/FileInputStream$UseManualSkipException", NULL);
97      } else {
98        JNU_ThrowIOExceptionWithLastError(env, "Seek error");
99      }
100    } else if ((end = IO_Lseek(fd, toSkip, (jint)SEEK_CUR)) == -1) {
101        JNU_ThrowIOExceptionWithLastError(env, "Seek error");
102    }
103    return (end - cur);
104}
105
106static int available(int fd, jlong *bytes) {
107  int n;
108  // Unlike the original OpenJdk implementation, we use FIONREAD for all file
109  // types. For regular files, this is specified to return the difference
110  // between the current position and the file size. Note that this can be
111  // negative if we're positioned past the end of the file. We must return 0
112  // in that case.
113  if (ioctl(fd, FIONREAD, &n) != -1) {
114    if (n < 0) {
115      n = 0;
116    }
117    *bytes = n;
118    return 1;
119  }
120
121  // FIONREAD is specified to return ENOTTY when fd refers to a file
122  // type for which this ioctl isn't implemented.
123  if (errno == ENOTTY) {
124    *bytes = 0;
125    return 1;
126  }
127
128  // Raise an exception for all other error types.
129  return 0;
130}
131
132JNIEXPORT jint JNICALL
133FileInputStream_available0(JNIEnv *env, jobject this) {
134    jlong ret;
135    FD fd = GET_FD(this, fis_fd);
136    if (fd == -1) {
137        JNU_ThrowIOException (env, "Stream Closed");
138        return 0;
139    }
140    if (available(fd, &ret)) {
141        if (ret > INT_MAX) {
142            ret = (jlong) INT_MAX;
143        }
144        return jlong_to_jint(ret);
145    }
146    JNU_ThrowIOExceptionWithLastError(env, NULL);
147    return 0;
148}
149
150JNIEXPORT void JNICALL
151FileInputStream_close0(JNIEnv *env, jobject this) {
152    fileClose(env, this, fis_fd);
153}
154
155static JNINativeMethod gMethods[] = {
156  NATIVE_METHOD(FileInputStream, initIDs, "()V"),
157  NATIVE_METHOD(FileInputStream, open, "(Ljava/lang/String;)V"),
158  NATIVE_METHOD(FileInputStream, skip0, "(J)J"),
159  NATIVE_METHOD(FileInputStream, available0, "()I"),
160  //NATIVE_METHOD(FileInputStream, read0, "()I"),
161  //NATIVE_METHOD(FileInputStream, readBytes, "([BII)I"),
162  //NATIVE_METHOD(FileInputStream, close0, "()V"),
163};
164
165void register_java_io_FileInputStream(JNIEnv* env) {
166  jniRegisterNativeMethods(env, "java/io/FileInputStream", gMethods, NELEM(gMethods));
167}
168