android_util_Log.cpp revision 8685a4569d2bdcb1a7361e3d75f832cf3ba9d4b6 
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 "core_jni_helpers.h"
30#include "android_util_Log.h"
31
32namespace android {
33
34struct levels_t {
35    jint verbose;
36    jint debug;
37    jint info;
38    jint warn;
39    jint error;
40    jint assert;
41};
42static levels_t levels;
43
44static jboolean isLoggable(const char* tag, jint level) {
45    return __android_log_is_loggable(level, tag, ANDROID_LOG_INFO);
46}
47
48static jboolean android_util_Log_isLoggable(JNIEnv* env, jobject clazz, jstring tag, jint level)
49{
50    if (tag == NULL) {
51        return false;
52    }
53
54    const char* chars = env->GetStringUTFChars(tag, NULL);
55    if (!chars) {
56        return false;
57    }
58
59    jboolean result = false;
60    if ((strlen(chars)+sizeof(LOG_NAMESPACE)) > PROPERTY_KEY_MAX) {
61        char buf2[200];
62        snprintf(buf2, sizeof(buf2), "Log tag \"%s\" exceeds limit of %zu characters\n",
63                chars, PROPERTY_KEY_MAX - sizeof(LOG_NAMESPACE));
64
65        jniThrowException(env, "java/lang/IllegalArgumentException", buf2);
66    } else {
67        result = isLoggable(chars, level);
68    }
69
70    env->ReleaseStringUTFChars(tag, chars);
71    return result;
72}
73
74bool android_util_Log_isVerboseLogEnabled(const char* tag) {
75    return isLoggable(tag, levels.verbose);
76}
77
78/*
79 * In class android.util.Log:
80 *  public static native int println_native(int buffer, int priority, String tag, String msg)
81 */
82static jint android_util_Log_println_native(JNIEnv* env, jobject clazz,
83        jint bufID, jint priority, jstring tagObj, jstring msgObj)
84{
85    const char* tag = NULL;
86    const char* msg = NULL;
87
88    if (msgObj == NULL) {
89        jniThrowNullPointerException(env, "println needs a message");
90        return -1;
91    }
92
93    if (bufID < 0 || bufID >= LOG_ID_MAX) {
94        jniThrowNullPointerException(env, "bad bufID");
95        return -1;
96    }
97
98    if (tagObj != NULL)
99        tag = env->GetStringUTFChars(tagObj, NULL);
100    msg = env->GetStringUTFChars(msgObj, NULL);
101
102    int res = __android_log_buf_write(bufID, (android_LogPriority)priority, tag, msg);
103
104    if (tag != NULL)
105        env->ReleaseStringUTFChars(tagObj, tag);
106    env->ReleaseStringUTFChars(msgObj, msg);
107
108    return res;
109}
110
111/*
112 * JNI registration.
113 */
114static JNINativeMethod gMethods[] = {
115    /* name, signature, funcPtr */
116    { "isLoggable",      "(Ljava/lang/String;I)Z", (void*) android_util_Log_isLoggable },
117    { "println_native",  "(IILjava/lang/String;Ljava/lang/String;)I", (void*) android_util_Log_println_native },
118};
119
120int register_android_util_Log(JNIEnv* env)
121{
122    jclass clazz = FindClassOrDie(env, "android/util/Log");
123
124    levels.verbose = env->GetStaticIntField(clazz, GetStaticFieldIDOrDie(env, clazz, "VERBOSE", "I"));
125    levels.debug = env->GetStaticIntField(clazz, GetStaticFieldIDOrDie(env, clazz, "DEBUG", "I"));
126    levels.info = env->GetStaticIntField(clazz, GetStaticFieldIDOrDie(env, clazz, "INFO", "I"));
127    levels.warn = env->GetStaticIntField(clazz, GetStaticFieldIDOrDie(env, clazz, "WARN", "I"));
128    levels.error = env->GetStaticIntField(clazz, GetStaticFieldIDOrDie(env, clazz, "ERROR", "I"));
129    levels.assert = env->GetStaticIntField(clazz, GetStaticFieldIDOrDie(env, clazz, "ASSERT", "I"));
130
131    return RegisterMethodsOrDie(env, "android/util/Log", gMethods, NELEM(gMethods));
132}
133
134}; // namespace android
135