1 /*
2 * Copyright (c) 1997, 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 extern jfieldID IO_fd_fdID;
30 extern jfieldID IO_handle_fdID;
31 extern jfieldID IO_append_fdID;
32
33 #ifdef _ALLBSD_SOURCE
34 #include <fcntl.h>
35 #ifndef O_SYNC
36 #define O_SYNC O_FSYNC
37 #endif
38 #ifndef O_DSYNC
39 #define O_DSYNC O_FSYNC
40 #endif
41 #elif !defined(O_DSYNC) || !defined(O_SYNC)
42 #define O_SYNC (0x0800)
43 #define O_DSYNC (0x2000)
44 #endif
45
46 /*
47 * IO helper functions
48 */
49
50 jint readSingle(JNIEnv *env, jobject this, jfieldID fid);
51 jint readBytes(JNIEnv *env, jobject this, jbyteArray bytes, jint off,
52 jint len, jfieldID fid);
53 void writeSingle(JNIEnv *env, jobject this, jint byte, jboolean append, jfieldID fid);
54 void writeBytes(JNIEnv *env, jobject this, jbyteArray bytes, jint off,
55 jint len, jboolean append, jfieldID fid);
56 void fileOpen(JNIEnv *env, jobject this, jstring path, jfieldID fid, int flags);
57 JNIEXPORT void JNICALL
58 throwFileNotFoundException(JNIEnv *env, jstring path);
59
60 /*
61 * Macros for managing platform strings. The typical usage pattern is:
62 *
63 * WITH_PLATFORM_STRING(env, string, var) {
64 * doSomethingWith(var);
65 * } END_PLATFORM_STRING(env, var);
66 *
67 * where env is the prevailing JNIEnv,
68 * string is a JNI reference to a java.lang.String object, and
69 * var is the char * variable that will point to the string,
70 * after being converted into the platform encoding.
71 *
72 * The related macro WITH_FIELD_PLATFORM_STRING first extracts the string from
73 * a given field of a given object:
74 *
75 * WITH_FIELD_PLATFORM_STRING(env, object, id, var) {
76 * doSomethingWith(var);
77 * } END_PLATFORM_STRING(env, var);
78 *
79 * where env is the prevailing JNIEnv,
80 * object is a jobject,
81 * id is the field ID of the String field to be extracted, and
82 * var is the char * variable that will point to the string.
83 *
84 * Uses of these macros may be nested as long as each WITH_.._STRING macro
85 * declares a unique variable.
86 */
87
88 #define WITH_PLATFORM_STRING(env, strexp, var) \
89 if (1) { \
90 const char *var; \
91 jstring _##var##str = (strexp); \
92 if (_##var##str == NULL) { \
93 JNU_ThrowNullPointerException((env), NULL); \
94 goto _##var##end; \
95 } \
96 var = JNU_GetStringPlatformChars((env), _##var##str, NULL); \
97 if (var == NULL) goto _##var##end;
98
99 #define WITH_FIELD_PLATFORM_STRING(env, object, id, var) \
100 WITH_PLATFORM_STRING(env, \
101 ((object == NULL) \
102 ? NULL \
103 : (*(env))->GetObjectField((env), (object), (id))), \
104 var)
105
106 #define END_PLATFORM_STRING(env, var) \
107 JNU_ReleaseStringPlatformChars(env, _##var##str, var); \
108 _##var##end: ; \
109 } else ((void)NULL)
110
111
112 /* Macros for transforming Java Strings into native Unicode strings.
113 * Works analogously to WITH_PLATFORM_STRING.
114 */
115
116 #define WITH_UNICODE_STRING(env, strexp, var) \
117 if (1) { \
118 const jchar *var; \
119 jstring _##var##str = (strexp); \
120 if (_##var##str == NULL) { \
121 JNU_ThrowNullPointerException((env), NULL); \
122 goto _##var##end; \
123 } \
124 var = (*(env))->GetStringChars((env), _##var##str, NULL); \
125 if (var == NULL) goto _##var##end;
126
127 #define END_UNICODE_STRING(env, var) \
128 (*(env))->ReleaseStringChars(env, _##var##str, var); \
129 _##var##end: ; \
130 } else ((void)NULL)