无法在本机活动应用程序中加载具有依赖项的本机共享库 [英] Can't load native shared library with dependencies in a native activity app

问题描述

在我的 Android 应用中，我有 4 个库:

In my Android app I have 4 libraries:

libTemplate.so
   depends on libPorkholt.so
libPorkholt.so
   depends on libpng15.so
   depends on liblua.so
   depends on libopenal.so
libpng15.so
liblua.so
libopenal.so

如果我编写一个与 libTemplate 链接并手动调用 ANativeActivity_onCreate 的小型命令行可执行文件，它会链接并运行得很好(如果我将 LD_LIBRARY_PATH 指向/data/data/com.mycompany.Template/lib)

If I write a small command line executable that links against libTemplate and manually call ANativeActivity_onCreate, it links and runs just fine (if I point LD_LIBRARY_PATH to /data/data/com.mycompany.Template/lib)

如果我运行我的应用程序，我会收到这个非常有用的错误消息:

If I run my app I get this very useful error message:

E/AndroidRuntime(13214): java.lang.RuntimeException: Unable to start activity ComponentInfo{com.mycompany.Template/android.app.NativeActivity}: java.lang.IllegalArgumentException: Unable to load native library: /data/data/com.mycompany.Template/lib/libTemplate.so

它甚至没有进入ANativeActivity_onCreate，所以我唯一的猜测是它与链接有关

It doesn't even enter ANativeActivity_onCreate, so my only guess is that's it has something to do with linking

我应该提到我正在使用 CMake 和这个脚本:http://code.google.com/p/android-cmake/ 自己构建库(没有 ndk-build).我设法用它编译了本机活动示例，所以我知道它可以工作.

I should probably mention that I'm using CMake with this script: http://code.google.com/p/android-cmake/ to build the libraries myself (without ndk-build). I managed to compile the native-activity sample with it, so I know it works.

另外，我确保没有库在其 soname 中包含版本号

Also, I made sure no library contains a version number in its soname

我的清单:

<?xml version="1.0" encoding="utf-8"?>
<!-- BEGIN_INCLUDE(manifest) -->
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
        package="com.mycompany.Template"
        android:versionCode="1"
        android:versionName="1.0">

    <!-- This is the platform API where NativeActivity was introduced. -->
    <uses-sdk android:minSdkVersion="9" />

    <!-- This .apk has no Java code itself, so set hasCode to false. -->
    <application android:label="Template Porkholt project" android:hasCode="false">

        <!-- Our activity is the built-in NativeActivity framework class.
             This will take care of integrating with our NDK code. -->
        <activity android:name="android.app.NativeActivity"
                android:label="Template Porkholt project"
                android:configChanges="orientation|keyboardHidden">
            <!-- Tell NativeActivity the name of or .so -->
            <meta-data android:name="android.app.lib_name"
                    android:value="Template" />
            <intent-filter>
                <action android:name="android.intent.action.MAIN" />
                <category android:name="android.intent.category.LAUNCHER" />
            </intent-filter>
        </activity>
    </application>

</manifest> 
<!-- END_INCLUDE(manifest) -->

推荐答案

由于显然 Android 不够聪明，无法正确设置 LD_LIBRARY_PATH，我设法通过创建一个手动加载实际活动的小型引导程序库来解决我的问题.代码如下:

Since apparently Android isn't smart enough to set a LD_LIBRARY_PATH correctly, I managed to solve my problem by creating a small bootstrapper library that manually loads the actual activity. Here's the code:

#include <android/native_activity.h>
#include <android/log.h>
#include <dlfcn.h>
#include <errno.h>
#include <stdlib.h>

#define LOGI(...) ((void)__android_log_print(ANDROID_LOG_INFO, "Porkholt", __VA_ARGS__))
#define LOGE(...) ((void)__android_log_print(ANDROID_LOG_ERROR, "Porkholt", __VA_ARGS__))

#define LIB_PATH "/data/data/@PH_BUNDLE_ID@/lib/"

void * load_lib(const char * l)
{
    void * handle = dlopen(l, RTLD_NOW | RTLD_GLOBAL);
    if (!handle)
    {
        LOGE("dlopen("%s"): %s", l, strerror(errno));
        exit(1);
    }
    return handle;
}

void ANativeActivity_onCreate(ANativeActivity * app, void * ud, size_t udsize)
{
    LOGI("Loaded bootstrap");
    load_lib(LIB_PATH "libpng15.so");
    load_lib(LIB_PATH "liblua.so");
    load_lib(LIB_PATH "libopenal.so");
    load_lib(LIB_PATH "libPorkholt.so");
    void (*main)(ANativeActivity*, void*, size_t) = dlsym(load_lib(LIB_PATH "lib@PH_APP_TARGET@.so"), "ANativeActivity_onCreate");
    if (!main)
    {
        LOGE("undefined symbol ANativeActivity_onCreate");
        exit(1);
    }
    main(app, ud, udsize);
}

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