1 /*
   2  * Copyright (c) 2003, 2018, 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 
  29 /*
  30  * Macros to use the right data type for file descriptors
  31  */
  32 #define FD jlong
  33 
  34 /*
  35  * Prototypes for functions in io_util_md.c called from io_util.c,
  36  * FileDescriptor.c, FileInputStream.c, FileOutputStream.c,
  37  * ProcessImpl_md.c
  38  */
  39 WCHAR* pathToNTPath(JNIEnv *env, jstring path, jboolean throwFNFE);
  40 WCHAR* fileToNTPath(JNIEnv *env, jobject file, jfieldID id);
  41 WCHAR* getPrefixed(const WCHAR* path, int pathlen);
  42 WCHAR* currentDir(int di);
  43 int currentDirLength(const WCHAR* path, int pathlen);
  44 int handleAvailable(FD fd, jlong *pbytes);
  45 int handleSync(FD fd);
  46 int handleSetLength(FD fd, jlong length);
  47 jlong handleGetLength(FD fd);
  48 JNIEXPORT jint handleRead(FD fd, void *buf, jint len);
  49 jint handleWrite(FD fd, const void *buf, jint len);
  50 jint handleAppend(FD fd, const void *buf, jint len);
  51 void handleClose(JNIEnv *env, jobject this, jfieldID fid);
  52 void fileDescriptorClose(JNIEnv *env, jobject this);
  53 JNIEXPORT jlong JNICALL
  54 handleLseek(FD fd, jlong offset, jint whence);
  55 
  56 /*
  57  * Returns an opaque handle to file named by "path".  If an error occurs,
  58  * returns -1 and an exception is pending.
  59  */
  60 JNIEXPORT FD JNICALL
  61 winFileHandleOpen(JNIEnv *env, jstring path, int flags);
  62 
  63 /*
  64  * Macros to set/get fd from the java.io.FileDescriptor.
  65  * If GetObjectField returns null, SET_FD will stop and GET_FD
  66  * will simply return -1 to avoid crashing VM.
  67  */
  68 #define SET_FD(this, fd, fid) \
  69     if ((*env)->GetObjectField(env, (this), (fid)) != NULL) \
  70         (*env)->SetLongField(env, (*env)->GetObjectField(env, (this), (fid)), IO_handle_fdID, (fd))
  71 
  72 #define GET_FD(this, fid) \
  73     ((*env)->GetObjectField(env, (this), (fid)) == NULL) ? \
  74       -1 : (*env)->GetLongField(env, (*env)->GetObjectField(env, (this), (fid)), IO_handle_fdID)
  75 
  76 /*
  77  * Macros to set/get fd when inside java.io.FileDescriptor
  78  */
  79 #define THIS_FD(obj) (*env)->GetLongField(env, obj, IO_handle_fdID)
  80 
  81 /*
  82  * Route the routines away from VM
  83  */
  84 #define IO_Append handleAppend
  85 #define IO_Write handleWrite
  86 #define IO_Sync handleSync
  87 #define IO_Read handleRead
  88 #define IO_Lseek handleLseek
  89 #define IO_Available handleAvailable
  90 #define IO_SetLength handleSetLength
  91 #define IO_GetLength handleGetLength
  92 
  93 /*
  94  * Setting the handle field in Java_java_io_FileDescriptor_set for
  95  * standard handles stdIn, stdOut, stdErr
  96  */
  97 #define SET_HANDLE(fd) \
  98 if (fd == 0) { \
  99     return (jlong)GetStdHandle(STD_INPUT_HANDLE); \
 100 } else if (fd == 1) { \
 101     return (jlong)GetStdHandle(STD_OUTPUT_HANDLE); \
 102 } else if (fd == 2) { \
 103     return (jlong)GetStdHandle(STD_ERROR_HANDLE); \
 104 } else { \
 105     return (jlong)-1; \
 106 } \
 107 
 108 /* INVALID_FILE_ATTRIBUTES is not defined in VC++6.0's header files but
 109  * in later release. Keep here just in case someone is still using VC++6.0
 110  */
 111 #ifndef INVALID_FILE_ATTRIBUTES
 112 #define INVALID_FILE_ATTRIBUTES ((DWORD)-1)
 113 #endif