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 
32 namespace android {
33 
34 struct levels_t {
35     jint verbose;
36     jint debug;
37     jint info;
38     jint warn;
39     jint error;
40     jint assert;
41 };
42 static levels_t levels;
43 
isLoggable(const char * tag,jint level)44 static jboolean isLoggable(const char* tag, jint level) {
45     return __android_log_is_loggable(level, tag, ANDROID_LOG_INFO);
46 }
47 
android_util_Log_isLoggable(JNIEnv * env,jobject clazz,jstring tag,jint level)48 static 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 
android_util_Log_isVerboseLogEnabled(const char * tag)74 bool 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  */
android_util_Log_println_native(JNIEnv * env,jobject clazz,jint bufID,jint priority,jstring tagObj,jstring msgObj)82 static 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  */
114 static 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 
register_android_util_Log(JNIEnv * env)120 int 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