io_util.h

/*
 * Copyright (c) 1997, 2018, Oracle and/or its affiliates. All rights reserved.
 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
 *
 * This code is free software; you can redistribute it and/or modify it
 * under the terms of the GNU General Public License version 2 only, as
 * published by the Free Software Foundation. Oracle designates this
 * particular file as subject to the "Classpath" exception as provided
 * by Oracle in the LICENSE file that accompanied this code.
 *
 * This code is distributed in the hope that it will be useful, but WITHOUT
 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
 * version 2 for more details (a copy is included in the LICENSE file that
 * accompanied this code).
 *
 * You should have received a copy of the GNU General Public License version
 * 2 along with this work; if not, write to the Free Software Foundation,
 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
 *
 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
 * or visit www.oracle.com if you need additional information or have any
 * questions.
 */

#include"jni.h"
#include"jni_util.h"

externjfieldIDIO_fd_fdID;
externjfieldIDIO_handle_fdID;
externjfieldIDIO_append_fdID;

#ifdef_ALLBSD_SOURCE
#include<fcntl.h>
#ifndefO_SYNC
#defineO_SYNC O_FSYNC
#endif
#ifndefO_DSYNC
#defineO_DSYNC O_FSYNC
#endif
#elif !defined(O_DSYNC) || !defined(O_SYNC)
#defineO_SYNC (0x0800)
#defineO_DSYNC (0x2000)
#endif

/*
 * IO helper functions
 */

jintreadSingle(JNIEnv*env, jobjectthis, jfieldIDfid);
jintreadBytes(JNIEnv*env, jobjectthis, jbyteArraybytes, jintoff,
jintlen, jfieldIDfid);
voidwriteSingle(JNIEnv*env, jobjectthis, jintbyte, jbooleanappend, jfieldIDfid);
voidwriteBytes(JNIEnv*env, jobjectthis, jbyteArraybytes, jintoff,
jintlen, jbooleanappend, jfieldIDfid);
voidfileOpen(JNIEnv*env, jobjectthis, jstringpath, jfieldIDfid, intflags);
voidthrowFileNotFoundException(JNIEnv*env, jstringpath);

/*
 * Macros for managing platform strings. The typical usage pattern is:
 *
 * WITH_PLATFORM_STRING(env, string, var) {
 * doSomethingWith(var);
 * } END_PLATFORM_STRING(env, var);
 *
 * where env is the prevailing JNIEnv,
 * string is a JNI reference to a java.lang.String object, and
 * var is the char * variable that will point to the string,
 * after being converted into the platform encoding.
 *
 * The related macro WITH_FIELD_PLATFORM_STRING first extracts the string from
 * a given field of a given object:
 *
 * WITH_FIELD_PLATFORM_STRING(env, object, id, var) {
 * doSomethingWith(var);
 * } END_PLATFORM_STRING(env, var);
 *
 * where env is the prevailing JNIEnv,
 * object is a jobject,
 * id is the field ID of the String field to be extracted, and
 * var is the char * variable that will point to the string.
 *
 * Uses of these macros may be nested as long as each WITH_.._STRING macro
 * declares a unique variable.
 */

#defineWITH_PLATFORM_STRING(env, strexp, var) \
 if (1) { \
 const char *var; \
 jstring _##var##str = (strexp); \
 if (_##var##str == NULL) { \
 JNU_ThrowNullPointerException((env), NULL); \
 goto _##var##end; \
 } \
 var = JNU_GetStringPlatformChars((env), _##var##str, NULL); \
 if (var == NULL) goto _##var##end;

#defineWITH_FIELD_PLATFORM_STRING(env, object, id, var) \
 WITH_PLATFORM_STRING(env, \
 ((object == NULL) \
 ? NULL \
 : (*(env))->GetObjectField((env), (object), (id))), \
 var)

#defineEND_PLATFORM_STRING(env, var) \
 JNU_ReleaseStringPlatformChars(env, _##var##str, var); \
 _##var##end: ; \
 } else ((void)NULL)


/* Macros for transforming Java Strings into native Unicode strings.
 * Works analogously to WITH_PLATFORM_STRING.
 */

#defineWITH_UNICODE_STRING(env, strexp, var) \
 if (1) { \
 const jchar *var; \
 jstring _##var##str = (strexp); \
 if (_##var##str == NULL) { \
 JNU_ThrowNullPointerException((env), NULL); \
 goto _##var##end; \
 } \
 var = (*(env))->GetStringChars((env), _##var##str, NULL); \
 if (var == NULL) goto _##var##end;

#defineEND_UNICODE_STRING(env, var) \
 (*(env))->ReleaseStringChars(env, _##var##str, var); \
 _##var##end: ; \
 } else ((void)NULL)