1 /*
   2  * Copyright (c) 1997, 2013, 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 "jlong.h"
  29 #include "io_util.h"
  30 
  31 #include "jvm.h"
  32 
  33 #include "java_io_FileInputStream.h"
  34 
  35 #include <fcntl.h>
  36 #include <limits.h>
  37 
  38 #include "io_util_md.h"
  39 
  40 /*******************************************************************/
  41 /*  BEGIN JNI ********* BEGIN JNI *********** BEGIN JNI ************/
  42 /*******************************************************************/
  43 
  44 jfieldID fis_fd; /* id for jobject 'fd' in java.io.FileInputStream */
  45 
  46 /**************************************************************
  47  * static methods to store field ID's in initializers
  48  */
  49 
  50 JNIEXPORT void JNICALL
  51 Java_java_io_FileInputStream_initIDs(JNIEnv *env, jclass fdClass) {
  52     fis_fd = (*env)->GetFieldID(env, fdClass, "fd", "Ljava/io/FileDescriptor;");
  53 }
  54 
  55 /**************************************************************
  56  * Input stream
  57  */
  58 
  59 JNIEXPORT void JNICALL
  60 Java_java_io_FileInputStream_open0(JNIEnv *env, jobject this, jstring path) {
  61     fileOpen(env, this, path, fis_fd, O_RDONLY);
  62 }
  63 
  64 JNIEXPORT jint JNICALL
  65 Java_java_io_FileInputStream_read0(JNIEnv *env, jobject this) {
  66     return readSingle(env, this, fis_fd);
  67 }
  68 
  69 JNIEXPORT jint JNICALL
  70 Java_java_io_FileInputStream_readBytes(JNIEnv *env, jobject this,
  71         jbyteArray bytes, jint off, jint len) {
  72     return readBytes(env, this, bytes, off, len, fis_fd);
  73 }
  74 
  75 JNIEXPORT jlong JNICALL
  76 Java_java_io_FileInputStream_skip(JNIEnv *env, jobject this, jlong toSkip) {
  77     jlong cur = jlong_zero;
  78     jlong end = jlong_zero;
  79     FD fd = GET_FD(this, fis_fd);
  80     if (fd == -1) {
  81         JNU_ThrowIOException (env, "Stream Closed");
  82         return 0;
  83     }
  84     if ((cur = IO_Lseek(fd, (jlong)0, (jint)SEEK_CUR)) == -1) {
  85         JNU_ThrowIOExceptionWithLastError(env, "Seek error");
  86     } else if ((end = IO_Lseek(fd, toSkip, (jint)SEEK_CUR)) == -1) {
  87         JNU_ThrowIOExceptionWithLastError(env, "Seek error");
  88     }
  89     return (end - cur);
  90 }
  91 
  92 JNIEXPORT jint JNICALL
  93 Java_java_io_FileInputStream_available(JNIEnv *env, jobject this) {
  94     jlong ret;
  95     FD fd = GET_FD(this, fis_fd);
  96     if (fd == -1) {
  97         JNU_ThrowIOException (env, "Stream Closed");
  98         return 0;
  99     }
 100     if (IO_Available(fd, &ret)) {
 101         if (ret > INT_MAX) {
 102             ret = (jlong) INT_MAX;
 103         } else if (ret < 0) {
 104             ret = 0;
 105         }
 106         return jlong_to_jint(ret);
 107     }
 108     JNU_ThrowIOExceptionWithLastError(env, NULL);
 109     return 0;
 110 }