Android NDK 를 이용한 lib 만들기

1. NDK 디렉토리의 구성

/android-ndk-r3/apps/dc-config/Application.mk
/android-ndk-r3/apps/dc-config/project/
/android-ndk-r3/apps/dc-config/project/jni/
/android-ndk-r3/apps/dc-config/project/jni/Android.mk
/android-ndk-r3/apps/dc-config/project/jni/dc-config.c
/android-ndk-r3/apps/dc-config/project/libs/
/android-ndk-r3/apps/dc-config/project/libs/armeabi/
/android-ndk-r3/apps/dc-config/project/libs/armeabi/libdc-config.so

• /android-ndk-r3/apps/dc-config/Application.mk
  APP_PROJECT_PATH := $(call my-dir)/project
  APP_MODULES      := dc-config
  
  
• /android-ndk-r3/apps/dc-config/project/jni/Android.mk
  LOCAL_PATH := $(call my-dir)
  
  include $(CLEAR_VARS)
  
  LOCAL_MODULE    := dc-config
  LOCAL_SRC_FILES := dc-config.c
  LOCAL_LDLIBS := -llog
  
  include $(BUILD_SHARED_LIBRARY)
  
  
• /android-ndk-r3/apps/dc-config/project/jni/dc-config.c
  #include ＜string.h＞
  #include ＜jni.h＞
  #include ＜stdlib.h＞
  #include ＜unistd.h＞
  
  #include ＜android/log.h＞
  #define LOG_TAG "DC-CONFIG"
  #define LOGD(...) __android_log_print(ANDROID_LOG_DEBUG, LOG_TAG, __VA_ARGS__);
  
  /*
   * LIB를 사용하는 JAVA CLASS 에  정의된 package 명과 동일한 구조로 함수명을 작성한다(?)
   * Java_[PACKAGE]_[CLASS NAME]_[FUNCTION NAME](JNIEnv* env, jobject thiz)
   * /Eclair/packages/apps/Phone/src/com/android/phone/CdmaDataCallCheckBoxPreference.java
   * package com.android.phone;
   * public class CdmaDataCallCheckBoxPreference extends CheckBoxPreference {
   * public native String  stringFromJNI();
   */
  jstring
  Java_com_android_phone_CdmaDataCallCheckBoxPreference_stringFromJNI( JNIEnv* env,
                                                    jobject thiz )
  {
      int rtn = 0;
  
      LOGD("PPPD_RUNNER START");
      rtn = system("/system/bin/pppd_runner");
      LOGD("PPPD_RUNNER START [%d]", rtn);
  
      return (*env)->NewStringUTF(env, "TEST Hello from JNI !");
  }
  
  
• /android-ndk-r3/apps/dc-config/project/libs/armeabi/libdc-config.so
  컴파일 후 생성되는 lib 파일
  
  
1. 컴파일
   
   
   

   # cd /android-ndk-r3/
   # make APP=dc-config

2. 사용
   
   
   
   

   /Eclair/packages/apps/Phone/src/com/android/phone/CdmaDataCallCheckBoxPreference.java
   
   package com.android.phone;
   
   ( ... )
   
   public class CdmaDataCallCheckBoxPreference extends CheckBoxPreference {
   {
       @Override
       public void onCreate(Bundle savedInstanceState)
       {
           super.onCreate(savedInstanceState);
   
           TextView  tv = new TextView(   this );
           tv.setText( stringFromJNI() );
           setContentView(tv);
       }
       public native String  stringFromJNI();
       static {
   

           System.loadLibrary("dc-config");

       }

   }

3. 파일시스템에 라이브러리 추가
   
   
   

   /system/lib/libdc-config.so