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