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      1 /* //device/libs/android_runtime/android_util_Log.cpp
      2 **
      3 ** Copyright 2006, The Android Open Source Project
      4 **
      5 ** Licensed under the Apache License, Version 2.0 (the "License");
      6 ** you may not use this file except in compliance with the License.
      7 ** You may obtain a copy of the License at
      8 **
      9 **     http://www.apache.org/licenses/LICENSE-2.0
     10 **
     11 ** Unless required by applicable law or agreed to in writing, software
     12 ** distributed under the License is distributed on an "AS IS" BASIS,
     13 ** WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
     14 ** See the License for the specific language governing permissions and
     15 ** limitations under the License.
     16 */
     17 
     18 #define LOG_NAMESPACE "log.tag."
     19 #define LOG_TAG "Log_println"
     20 
     21 #include <assert.h>
     22 #include <cutils/properties.h>
     23 #include <utils/Log.h>
     24 #include <utils/String8.h>
     25 
     26 #include "jni.h"
     27 #include "JNIHelp.h"
     28 #include "utils/misc.h"
     29 #include "android_runtime/AndroidRuntime.h"
     30 
     31 #define MIN(a,b) ((a<b)?a:b)
     32 
     33 namespace android {
     34 
     35 struct levels_t {
     36     jint verbose;
     37     jint debug;
     38     jint info;
     39     jint warn;
     40     jint error;
     41     jint assert;
     42 };
     43 static levels_t levels;
     44 
     45 static int toLevel(const char* value)
     46 {
     47     switch (value[0]) {
     48         case 'V': return levels.verbose;
     49         case 'D': return levels.debug;
     50         case 'I': return levels.info;
     51         case 'W': return levels.warn;
     52         case 'E': return levels.error;
     53         case 'A': return levels.assert;
     54         case 'S': return -1; // SUPPRESS
     55     }
     56     return levels.info;
     57 }
     58 
     59 static jboolean android_util_Log_isLoggable(JNIEnv* env, jobject clazz, jstring tag, jint level)
     60 {
     61     int len;
     62     char key[PROPERTY_KEY_MAX];
     63     char buf[PROPERTY_VALUE_MAX];
     64 
     65     if (tag == NULL) {
     66         return false;
     67     }
     68 
     69     jboolean result = false;
     70 
     71     const char* chars = env->GetStringUTFChars(tag, NULL);
     72 
     73     if ((strlen(chars)+sizeof(LOG_NAMESPACE)) > PROPERTY_KEY_MAX) {
     74         char buf2[200];
     75         snprintf(buf2, sizeof(buf2), "Log tag \"%s\" exceeds limit of %d characters\n",
     76                 chars, PROPERTY_KEY_MAX - sizeof(LOG_NAMESPACE));
     77 
     78         // release the chars!
     79         env->ReleaseStringUTFChars(tag, chars);
     80 
     81         jniThrowException(env, "java/lang/IllegalArgumentException", buf2);
     82         return false;
     83     } else {
     84         strncpy(key, LOG_NAMESPACE, sizeof(LOG_NAMESPACE)-1);
     85         strcpy(key + sizeof(LOG_NAMESPACE) - 1, chars);
     86     }
     87 
     88     env->ReleaseStringUTFChars(tag, chars);
     89 
     90     len = property_get(key, buf, "");
     91     int logLevel = toLevel(buf);
     92     return (logLevel >= 0 && level >= logLevel) ? true : false;
     93 }
     94 
     95 /*
     96  * In class android.util.Log:
     97  *  public static native int println_native(int buffer, int priority, String tag, String msg)
     98  */
     99 static jint android_util_Log_println_native(JNIEnv* env, jobject clazz,
    100         jint bufID, jint priority, jstring tagObj, jstring msgObj)
    101 {
    102     const char* tag = NULL;
    103     const char* msg = NULL;
    104 
    105     if (msgObj == NULL) {
    106         jniThrowNullPointerException(env, "println needs a message");
    107         return -1;
    108     }
    109 
    110     if (bufID < 0 || bufID >= LOG_ID_MAX) {
    111         jniThrowNullPointerException(env, "bad bufID");
    112         return -1;
    113     }
    114 
    115     if (tagObj != NULL)
    116         tag = env->GetStringUTFChars(tagObj, NULL);
    117     msg = env->GetStringUTFChars(msgObj, NULL);
    118 
    119     int res = __android_log_buf_write(bufID, (android_LogPriority)priority, tag, msg);
    120 
    121     if (tag != NULL)
    122         env->ReleaseStringUTFChars(tagObj, tag);
    123     env->ReleaseStringUTFChars(msgObj, msg);
    124 
    125     return res;
    126 }
    127 
    128 /*
    129  * JNI registration.
    130  */
    131 static JNINativeMethod gMethods[] = {
    132     /* name, signature, funcPtr */
    133     { "isLoggable",      "(Ljava/lang/String;I)Z", (void*) android_util_Log_isLoggable },
    134     { "println_native",  "(IILjava/lang/String;Ljava/lang/String;)I", (void*) android_util_Log_println_native },
    135 };
    136 
    137 int register_android_util_Log(JNIEnv* env)
    138 {
    139     jclass clazz = env->FindClass("android/util/Log");
    140 
    141     if (clazz == NULL) {
    142         LOGE("Can't find android/util/Log");
    143         return -1;
    144     }
    145 
    146     levels.verbose = env->GetStaticIntField(clazz, env->GetStaticFieldID(clazz, "VERBOSE", "I"));
    147     levels.debug = env->GetStaticIntField(clazz, env->GetStaticFieldID(clazz, "DEBUG", "I"));
    148     levels.info = env->GetStaticIntField(clazz, env->GetStaticFieldID(clazz, "INFO", "I"));
    149     levels.warn = env->GetStaticIntField(clazz, env->GetStaticFieldID(clazz, "WARN", "I"));
    150     levels.error = env->GetStaticIntField(clazz, env->GetStaticFieldID(clazz, "ERROR", "I"));
    151     levels.assert = env->GetStaticIntField(clazz, env->GetStaticFieldID(clazz, "ASSERT", "I"));
    152 
    153     return AndroidRuntime::registerNativeMethods(env, "android/util/Log", gMethods, NELEM(gMethods));
    154 }
    155 
    156 }; // namespace android
    157