android_util_Log.cpp revision 8413db8c36f4ba5979cdc2b1c3e1429e6ba34d6a 
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 <android-base/macros.h>
22#include <assert.h>
23#include <cutils/properties.h>
24#include <log/logger.h>               // For LOGGER_ENTRY_MAX_PAYLOAD.
25#include <utils/Log.h>
26#include <utils/String8.h>
27
28#include "jni.h"
29#include "JNIHelp.h"
30#include "utils/misc.h"
31#include "core_jni_helpers.h"
32#include "android_util_Log.h"
33
34namespace android {
35
36struct levels_t {
37    jint verbose;
38    jint debug;
39    jint info;
40    jint warn;
41    jint error;
42    jint assert;
43};
44static levels_t levels;
45
46static jboolean isLoggable(const char* tag, jint level) {
47    return __android_log_is_loggable(level, tag, ANDROID_LOG_INFO);
48}
49
50static jboolean android_util_Log_isLoggable(JNIEnv* env, jobject clazz, jstring tag, jint level)
51{
52    if (tag == NULL) {
53        return false;
54    }
55
56    const char* chars = env->GetStringUTFChars(tag, NULL);
57    if (!chars) {
58        return false;
59    }
60
61    jboolean result = false;
62    if ((strlen(chars)+sizeof(LOG_NAMESPACE)) > PROPERTY_KEY_MAX) {
63        char buf2[200];
64        snprintf(buf2, sizeof(buf2), "Log tag \"%s\" exceeds limit of %zu characters\n",
65                chars, PROPERTY_KEY_MAX - sizeof(LOG_NAMESPACE));
66
67        jniThrowException(env, "java/lang/IllegalArgumentException", buf2);
68    } else {
69        result = isLoggable(chars, level);
70    }
71
72    env->ReleaseStringUTFChars(tag, chars);
73    return result;
74}
75
76bool android_util_Log_isVerboseLogEnabled(const char* tag) {
77    return isLoggable(tag, levels.verbose);
78}
79
80/*
81 * In class android.util.Log:
82 *  public static native int println_native(int buffer, int priority, String tag, String msg)
83 */
84static jint android_util_Log_println_native(JNIEnv* env, jobject clazz,
85        jint bufID, jint priority, jstring tagObj, jstring msgObj)
86{
87    const char* tag = NULL;
88    const char* msg = NULL;
89
90    if (msgObj == NULL) {
91        jniThrowNullPointerException(env, "println needs a message");
92        return -1;
93    }
94
95    if (bufID < 0 || bufID >= LOG_ID_MAX) {
96        jniThrowNullPointerException(env, "bad bufID");
97        return -1;
98    }
99
100    if (tagObj != NULL)
101        tag = env->GetStringUTFChars(tagObj, NULL);
102    msg = env->GetStringUTFChars(msgObj, NULL);
103
104    int res = __android_log_buf_write(bufID, (android_LogPriority)priority, tag, msg);
105
106    if (tag != NULL)
107        env->ReleaseStringUTFChars(tagObj, tag);
108    env->ReleaseStringUTFChars(msgObj, msg);
109
110    return res;
111}
112
113/*
114 * In class android.util.Log:
115 *  private static native int logger_entry_max_payload_native()
116 */
117static jint android_util_Log_logger_entry_max_payload_native(JNIEnv* env ATTRIBUTE_UNUSED,
118                                                             jobject clazz ATTRIBUTE_UNUSED)
119{
120    return static_cast<jint>(LOGGER_ENTRY_MAX_PAYLOAD);
121}
122
123/*
124 * JNI registration.
125 */
126static const JNINativeMethod gMethods[] = {
127    /* name, signature, funcPtr */
128    { "isLoggable",      "(Ljava/lang/String;I)Z", (void*) android_util_Log_isLoggable },
129    { "println_native",  "(IILjava/lang/String;Ljava/lang/String;)I", (void*) android_util_Log_println_native },
130    { "logger_entry_max_payload_native",  "()I", (void*) android_util_Log_logger_entry_max_payload_native },
131};
132
133int register_android_util_Log(JNIEnv* env)
134{
135    jclass clazz = FindClassOrDie(env, "android/util/Log");
136
137    levels.verbose = env->GetStaticIntField(clazz, GetStaticFieldIDOrDie(env, clazz, "VERBOSE", "I"));
138    levels.debug = env->GetStaticIntField(clazz, GetStaticFieldIDOrDie(env, clazz, "DEBUG", "I"));
139    levels.info = env->GetStaticIntField(clazz, GetStaticFieldIDOrDie(env, clazz, "INFO", "I"));
140    levels.warn = env->GetStaticIntField(clazz, GetStaticFieldIDOrDie(env, clazz, "WARN", "I"));
141    levels.error = env->GetStaticIntField(clazz, GetStaticFieldIDOrDie(env, clazz, "ERROR", "I"));
142    levels.assert = env->GetStaticIntField(clazz, GetStaticFieldIDOrDie(env, clazz, "ASSERT", "I"));
143
144    return RegisterMethodsOrDie(env, "android/util/Log", gMethods, NELEM(gMethods));
145}
146
147}; // namespace android
148