xref: /onnv-gate/usr/src/lib/libslp/clib/slp_jni_support.c (revision 0:68f95e015346)
1*0Sstevel@tonic-gate /*
2*0Sstevel@tonic-gate  * CDDL HEADER START
3*0Sstevel@tonic-gate  *
4*0Sstevel@tonic-gate  * The contents of this file are subject to the terms of the
5*0Sstevel@tonic-gate  * Common Development and Distribution License, Version 1.0 only
6*0Sstevel@tonic-gate  * (the "License").  You may not use this file except in compliance
7*0Sstevel@tonic-gate  * with the License.
8*0Sstevel@tonic-gate  *
9*0Sstevel@tonic-gate  * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
10*0Sstevel@tonic-gate  * or http://www.opensolaris.org/os/licensing.
11*0Sstevel@tonic-gate  * See the License for the specific language governing permissions
12*0Sstevel@tonic-gate  * and limitations under the License.
13*0Sstevel@tonic-gate  *
14*0Sstevel@tonic-gate  * When distributing Covered Code, include this CDDL HEADER in each
15*0Sstevel@tonic-gate  * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
16*0Sstevel@tonic-gate  * If applicable, add the following below this CDDL HEADER, with the
17*0Sstevel@tonic-gate  * fields enclosed by brackets "[]" replaced with your own identifying
18*0Sstevel@tonic-gate  * information: Portions Copyright [yyyy] [name of copyright owner]
19*0Sstevel@tonic-gate  *
20*0Sstevel@tonic-gate  * CDDL HEADER END
21*0Sstevel@tonic-gate  */
22*0Sstevel@tonic-gate /*
23*0Sstevel@tonic-gate  * Copyright 1998,2003 Sun Microsystems, Inc.  All rights reserved.
24*0Sstevel@tonic-gate  * Use is subject to license terms.
25*0Sstevel@tonic-gate  */
26*0Sstevel@tonic-gate 
27*0Sstevel@tonic-gate #pragma ident	"%Z%%M%	%I%	%E% SMI"
28*0Sstevel@tonic-gate 
29*0Sstevel@tonic-gate /*
30*0Sstevel@tonic-gate  * This file contains native methods for the Java SLP implementation.
31*0Sstevel@tonic-gate  * So far this is just the syslog function.
32*0Sstevel@tonic-gate  *
33*0Sstevel@tonic-gate  * The file also contains two support functions, one for throwing exceptions
34*0Sstevel@tonic-gate  * given a class name, and one for correctly converting unicode Strings to C
35*0Sstevel@tonic-gate  * byte arrays.
36*0Sstevel@tonic-gate  */
37*0Sstevel@tonic-gate 
38*0Sstevel@tonic-gate #include <malloc.h>
39*0Sstevel@tonic-gate #include <jni.h>
40*0Sstevel@tonic-gate #include <syslog.h>
41*0Sstevel@tonic-gate 
42*0Sstevel@tonic-gate #define	CLASS_JAVA_LANG_OUTOFMEMORYERROR "java/lang/OutOfMemoryError"
43*0Sstevel@tonic-gate #define	CLASS_JAVA_LANG_STRING "java/lang/String"
44*0Sstevel@tonic-gate 
45*0Sstevel@tonic-gate #define	METHOD_GETBYTES "getBytes"
46*0Sstevel@tonic-gate 
47*0Sstevel@tonic-gate #define	SIG_JAVA_LANG_STRING_GETBYTES "()[B"
48*0Sstevel@tonic-gate 
49*0Sstevel@tonic-gate /*
50*0Sstevel@tonic-gate  * Given a class name of an exception and a message attempt to throw
51*0Sstevel@tonic-gate  * a new instance of the exception.
52*0Sstevel@tonic-gate  */
53*0Sstevel@tonic-gate static void
JNU_ThrowByName(JNIEnv * env,const char * name,const char * msg)54*0Sstevel@tonic-gate JNU_ThrowByName(JNIEnv *env, const char *name, const char *msg)
55*0Sstevel@tonic-gate {
56*0Sstevel@tonic-gate 	jclass class = (*env)->FindClass(env, name);
57*0Sstevel@tonic-gate 
58*0Sstevel@tonic-gate 	/*
59*0Sstevel@tonic-gate 	 * If class is NULL FindClass() encountered a problem locating the
60*0Sstevel@tonic-gate 	 * desired class and has already called ThrowNew() with an
61*0Sstevel@tonic-gate 	 * exception.
62*0Sstevel@tonic-gate 	 */
63*0Sstevel@tonic-gate 	if (class == NULL) {
64*0Sstevel@tonic-gate 		return;
65*0Sstevel@tonic-gate 	}
66*0Sstevel@tonic-gate 
67*0Sstevel@tonic-gate 	(*env)->ThrowNew(env, class, msg);
68*0Sstevel@tonic-gate 	(*env)->DeleteLocalRef(env, class);
69*0Sstevel@tonic-gate }
70*0Sstevel@tonic-gate 
71*0Sstevel@tonic-gate /*
72*0Sstevel@tonic-gate  * Convert a Java String into a native set of characters using the
73*0Sstevel@tonic-gate  * method String.getBytes(). This will ensure that the appropriate
74*0Sstevel@tonic-gate  * character set encoding will be used. This is necessary if the
75*0Sstevel@tonic-gate  * Java String uses unicode characters that cannot be easily
76*0Sstevel@tonic-gate  * encoded into native chars.
77*0Sstevel@tonic-gate  *
78*0Sstevel@tonic-gate  * The buffer returned must be released by using free() once it is
79*0Sstevel@tonic-gate  * finished with.
80*0Sstevel@tonic-gate  *
81*0Sstevel@tonic-gate  * This function returns NULL if an exception has been thrown during its
82*0Sstevel@tonic-gate  * execution.
83*0Sstevel@tonic-gate  */
84*0Sstevel@tonic-gate static char
JNU_GetStringNativeChars(JNIEnv * env,jstring jstr)85*0Sstevel@tonic-gate *JNU_GetStringNativeChars(JNIEnv *env, jstring jstr)
86*0Sstevel@tonic-gate {
87*0Sstevel@tonic-gate 	jclass class;
88*0Sstevel@tonic-gate 	jmethodID method;
89*0Sstevel@tonic-gate 	jint len;
90*0Sstevel@tonic-gate 	jbyteArray bytes = NULL;
91*0Sstevel@tonic-gate 	char *result = NULL;
92*0Sstevel@tonic-gate 
93*0Sstevel@tonic-gate 	/*
94*0Sstevel@tonic-gate 	 * Need a local reference for (1) FindClass(), (2) the bytes and
95*0Sstevel@tonic-gate 	 * (3) the FindClass() in ThrowByName() if all goes wrong.
96*0Sstevel@tonic-gate 	 */
97*0Sstevel@tonic-gate 	if ((*env)->EnsureLocalCapacity(env, 3) < 0) {
98*0Sstevel@tonic-gate 		JNU_ThrowByName(
99*0Sstevel@tonic-gate 		    env,
100*0Sstevel@tonic-gate 		    CLASS_JAVA_LANG_OUTOFMEMORYERROR,
101*0Sstevel@tonic-gate 		    NULL);
102*0Sstevel@tonic-gate 
103*0Sstevel@tonic-gate 		return (NULL);
104*0Sstevel@tonic-gate 	}
105*0Sstevel@tonic-gate 
106*0Sstevel@tonic-gate 	class = (*env)->FindClass(env, CLASS_JAVA_LANG_STRING);
107*0Sstevel@tonic-gate 
108*0Sstevel@tonic-gate 	/*
109*0Sstevel@tonic-gate 	 * If class is NULL FindClass() encountered a problem locating the
110*0Sstevel@tonic-gate 	 * desired class and has already called ThrowNew() with an
111*0Sstevel@tonic-gate 	 * exception.
112*0Sstevel@tonic-gate 	 */
113*0Sstevel@tonic-gate 	if (class == NULL) {
114*0Sstevel@tonic-gate 		return (NULL);
115*0Sstevel@tonic-gate 	}
116*0Sstevel@tonic-gate 
117*0Sstevel@tonic-gate 	method = (*env)->GetMethodID(
118*0Sstevel@tonic-gate 	    env,
119*0Sstevel@tonic-gate 	    class,
120*0Sstevel@tonic-gate 	    METHOD_GETBYTES,
121*0Sstevel@tonic-gate 	    SIG_JAVA_LANG_STRING_GETBYTES);
122*0Sstevel@tonic-gate 
123*0Sstevel@tonic-gate 	/*
124*0Sstevel@tonic-gate 	 * If method is NULL GetMethodID() encountered a problem
125*0Sstevel@tonic-gate 	 * locating the desired method and has already called
126*0Sstevel@tonic-gate 	 * ThrowNew() with an exception.
127*0Sstevel@tonic-gate 	 */
128*0Sstevel@tonic-gate 	if (method != NULL) {
129*0Sstevel@tonic-gate 		/*
130*0Sstevel@tonic-gate 		 * Call String.getBytes(), creating our temporary
131*0Sstevel@tonic-gate 		 * byte array
132*0Sstevel@tonic-gate 		 */
133*0Sstevel@tonic-gate 		bytes = (*env)->CallObjectMethod(env, jstr, method);
134*0Sstevel@tonic-gate 
135*0Sstevel@tonic-gate 		/* See if CallObjectMethod() threw an exception */
136*0Sstevel@tonic-gate 		if ((*env)->ExceptionCheck(env) == JNI_FALSE) {
137*0Sstevel@tonic-gate 
138*0Sstevel@tonic-gate 			len = (*env)->GetArrayLength(env, bytes);
139*0Sstevel@tonic-gate 
140*0Sstevel@tonic-gate 			/*
141*0Sstevel@tonic-gate 			 * Allocate a buffer for the native characters,
142*0Sstevel@tonic-gate 			 * need an extra char for string terminator.
143*0Sstevel@tonic-gate 			 * Note: calloc will provide the terminating
144*0Sstevel@tonic-gate 			 * '\0' for us.
145*0Sstevel@tonic-gate 			 */
146*0Sstevel@tonic-gate 			result = (char *)calloc(len + 1, sizeof (char));
147*0Sstevel@tonic-gate 
148*0Sstevel@tonic-gate 			/*
149*0Sstevel@tonic-gate 			 * If allocation failed assume we are out of
150*0Sstevel@tonic-gate 			 * memory
151*0Sstevel@tonic-gate 			 */
152*0Sstevel@tonic-gate 			if (result == NULL) {
153*0Sstevel@tonic-gate 				JNU_ThrowByName(
154*0Sstevel@tonic-gate 				    env,
155*0Sstevel@tonic-gate 				    CLASS_JAVA_LANG_OUTOFMEMORYERROR,
156*0Sstevel@tonic-gate 				    NULL);
157*0Sstevel@tonic-gate 			} else {
158*0Sstevel@tonic-gate 				/*
159*0Sstevel@tonic-gate 				 * Copy the encoded bytes into the
160*0Sstevel@tonic-gate 				 * native string buffer
161*0Sstevel@tonic-gate 				 */
162*0Sstevel@tonic-gate 				(*env)->GetByteArrayRegion(
163*0Sstevel@tonic-gate 				    env,
164*0Sstevel@tonic-gate 				    bytes,
165*0Sstevel@tonic-gate 				    0,
166*0Sstevel@tonic-gate 				    len,
167*0Sstevel@tonic-gate 				    (jbyte *)result);
168*0Sstevel@tonic-gate 			}
169*0Sstevel@tonic-gate 		}
170*0Sstevel@tonic-gate 
171*0Sstevel@tonic-gate 		if (bytes != NULL) {
172*0Sstevel@tonic-gate 		    (*env)->DeleteLocalRef(env, bytes);
173*0Sstevel@tonic-gate 		}
174*0Sstevel@tonic-gate 	}
175*0Sstevel@tonic-gate 
176*0Sstevel@tonic-gate 	/* Clean up by deleting the local references */
177*0Sstevel@tonic-gate 	(*env)->DeleteLocalRef(env, class);
178*0Sstevel@tonic-gate 
179*0Sstevel@tonic-gate 	return (result);
180*0Sstevel@tonic-gate }
181*0Sstevel@tonic-gate 
182*0Sstevel@tonic-gate /*
183*0Sstevel@tonic-gate  * Class:     com_sun_slp_Syslog
184*0Sstevel@tonic-gate  * Method:    syslog
185*0Sstevel@tonic-gate  * Signature: (ILjava/lang/String;)V
186*0Sstevel@tonic-gate  */
187*0Sstevel@tonic-gate /* ARGSUSED */
188*0Sstevel@tonic-gate JNIEXPORT
Java_com_sun_slp_Syslog_syslog(JNIEnv * env,jobject obj,jint priority,jstring jmsg)189*0Sstevel@tonic-gate void JNICALL Java_com_sun_slp_Syslog_syslog(JNIEnv *env,
190*0Sstevel@tonic-gate 					    jobject obj,
191*0Sstevel@tonic-gate 					    jint priority,
192*0Sstevel@tonic-gate 					    jstring jmsg) {
193*0Sstevel@tonic-gate 
194*0Sstevel@tonic-gate 	char *msg = JNU_GetStringNativeChars(env, jmsg);
195*0Sstevel@tonic-gate 
196*0Sstevel@tonic-gate 	/*
197*0Sstevel@tonic-gate 	 * Check to see if the String conversion was successful,
198*0Sstevel@tonic-gate 	 * if it wasn't an exception will have already been thrown.
199*0Sstevel@tonic-gate 	 */
200*0Sstevel@tonic-gate 	if (msg != NULL) {
201*0Sstevel@tonic-gate 		openlog("slpd", LOG_PID, LOG_DAEMON);
202*0Sstevel@tonic-gate 		syslog(priority, "%s", msg);
203*0Sstevel@tonic-gate 		closelog();
204*0Sstevel@tonic-gate 
205*0Sstevel@tonic-gate 		free(msg);
206*0Sstevel@tonic-gate 	}
207*0Sstevel@tonic-gate }
208