Question

我以前曾经问过相同的问题（不同的NDK）here，并认为我正确构建了openssl，但是一旦尝试将其链接到我的应用程序后，我发现我没有正确构建它。

如果我桥接@AlexCohn here的答案，我将从setenv_android.sh脚本开始。
我修改了脚本，将THE_ARCH=arm64-v8a设置为尝试以64位android体系结构为目标。

当我运行脚本时，某些东西找不到：

ERROR: Failed to find Android cpp. Please edit this script.
ERROR: Failed to find Android gcc. Please edit this script.
ERROR: Failed to find Android g++. Please edit this script.
ERROR: AOSP_STL_INC is not valid. Please edit this script.
ERROR: AOSP_STL_LIB is not valid. Please edit this script.
ANDROID_NDK_ROOT: /Users/spartygw/android-ndk-r19/
AOSP_TOOLCHAIN_PATH: /Users/spartygw/android-ndk-r19//toolchains/aarch64-linux-android-4.9/prebuilt/darwin-x86_64/bin
AOSP_ABI: arm64-v8a
AOSP_API: android-21
AOSP_SYSROOT: /Users/spartygw/android-ndk-r19//platforms/android-21/arch-arm64
AOSP_FLAGS: -funwind-tables -fexceptions -frtti
AOSP_STL_INC: /Users/spartygw/android-ndk-r19//sources/cxx-stl/stlport/stlport/
AOSP_STL_LIB: /Users/spartygw/android-ndk-r19//sources/cxx-stl/stlport/libs/arm64-v8a/libstlport_shared.so

当我查看/Users/spartygw/android-ndk-r19//toolchains/aarch64-linux-android-4.9/prebuilt/darwin-x86_64/bin时，没有aarch64-linux-android-cpp或-gcc或-g++一样，如脚本输出所示：

$ ls -1 ~/android-ndk-r19//toolchains/aarch64-linux-android-4.9/prebuilt/darwin-x86_64/bin
./
../
aarch64-linux-android-addr2line
aarch64-linux-android-ar
aarch64-linux-android-as
aarch64-linux-android-c++filt
aarch64-linux-android-dwp
aarch64-linux-android-elfedit
aarch64-linux-android-gprof
aarch64-linux-android-ld
aarch64-linux-android-ld.bfd
aarch64-linux-android-ld.gold
aarch64-linux-android-nm
aarch64-linux-android-objcopy
aarch64-linux-android-objdump
aarch64-linux-android-ranlib
aarch64-linux-android-readelf
aarch64-linux-android-size
aarch64-linux-android-strings
aarch64-linux-android-strip

这是我上次遇到麻烦的地方。我开始对脚本进行黑客攻击，以获取似乎可以使用的功能，并且我确定自己现在做错了。

我真的不理解该过程，因此希望获得帮助。是否有人成功构建了OpenSLL的arm64-v8a版本？

Answer 1

我能够使用NDK r19为Android arm64构建，链接和运行openssl。但是我不得不使用从android-ndk-r19生成的独立工具链。

$ cd /path/to/android-ndk-r19
$ ./build/tools/make-standalone-toolchain.sh               \
            --toolchain=aarch64-linux-android

这将在您的tmp目录中生成一个名为aarch64-linux-android的目录，并将其bin目录放在您的路径中。另外，将您的ANDROID_NDK_HOME设置到此位置。

$ export PATH=/path/to/aarch64-linux-android/bin:${PATH}
$ export ANDROID_NDK_HOME=/path/to/aarch64-linux-android

然后只需运行openssl的Configure and make。

$ cd /path/to/openssl1.1.1
$ ./Configure android-arm64
$ make

./ Configure的输出如下：

$ ./Configure android-arm64
Configuring OpenSSL version 1.1.1b-dev (0x10101020L) for android-arm64
Using os-specific seed configuration
Creating configdata.pm
Creating Makefile

**********************************************************************
***                                                                ***
***   OpenSSL has been successfully configured                     ***
***                                                                ***
***   If you encounter a problem while building, please open an    ***
***   issue on GitHub <https://github.com/openssl/openssl/issues>  ***
***   and include the output from the following command:           ***
***                                                                ***
***       perl configdata.pm --dump                                ***
***                                                                ***
***   (If you are new to OpenSSL, you might want to consult the    ***
***   'Troubleshooting' section in the INSTALL file first)         ***
***                                                                ***
**********************************************************************
$

最后，我创建了一个新的Android Studio项目，该项目具有c ++ 11，异常和rtti支持（通过新的项目向导），并使用稍稍修改的CMakeLists.txt在构建的输出中进行了链接由Android Studio创建：

cmake_minimum_required(VERSION 3.4.1)

# Creates and names a library, sets it as either STATIC
# or SHARED, and provides the relative paths to its source code.
# You can define multiple libraries, and CMake builds them for you.
# Gradle automatically packages shared libraries with your APK.

add_library( # Sets the name of the library.
             native-lib

             # Sets the library as a shared library.
             SHARED

             # Provides a relative path to your source file(s).
             src/main/cpp/native-lib.cpp )

# Searches for a specified prebuilt library and stores the path as a
# variable. Because CMake includes system libraries in the search path by
# default, you only need to specify the name of the public NDK library
# you want to add. CMake verifies that the library exists before
# completing its build.

find_library( # Sets the name of the path variable.
              log-lib

              # Specifies the name of the NDK library that
              # you want CMake to locate.
              log )

# HERE ARE THE PARTS I EDITED:
# NOTE FOR THE COMMANDS ABOVE, THIS IS JUST THE OPENSSL SOURCE DIR.
set (SSL_PATH /path/to/ssl/build/outputs/)
include_directories(${SSL_PATH}/include)
set (open-ssl-libs ${SSL_PATH}/libssl.a ${SSL_PATH}/libcrypto.a)


# Specifies libraries CMake should link to your target library. You
# can link multiple libraries, such as libraries you define in this
# build script, prebuilt third-party libraries, or system libraries.

target_link_libraries( # Specifies the target library.
                       native-lib
                       # LINK SSL AND CRYPTO HERE:
                        ${open-ssl-libs}
                       # Links the target library to the log library
                       # included in the NDK.
                       ${log-lib} )

这足以表明它可以链接，但是我在Android Studio生成的样板c ++代码中为libssl.a添加了一个小引用：

#include <jni.h>
#include <string>
#include <openssl/ssl.h>

extern "C" JNIEXPORT jstring JNICALL
Java_com_vernier_android_test_1ssl_MainActivity_stringFromJNI(
        JNIEnv* env,
        jobject /* this */) {

    SSL* ssl = SSL_new(nullptr);
    std::string hello = "Hello from C++";
    return env->NewStringUTF(hello.c_str());
}

我成功运行了该应用程序。

Answer 2

我在使用addind SSL_PATH时遇到了麻烦。用

解决

set (SSL_PATH ${CMAKE_SOURCE_DIR}/src/main/cpp/openssl)

CMAKE_SOURCE_DIR已在Cmake中声明。

Answer 3

假设您已经有一个NDK，将cd转到该文件夹，输入/build/tools并运行以下命令。用所需的任何东西替换API，并指定放置独立工具链的文件夹。

python make_standalone_toolchain.py --install-dir=<standalone_toolchain_folder> --arch=arm64 --api=22

使用先前使用的路径，运行以下命令。

export ANDROID_NDK_HOME=<standalone_toolchain_folder>

PATH=$ANDROID_NDK_HOME/bin:$PATH

假设您已经下载并解压缩了OpenSSL，将cd放入文件夹并运行以下命令。

./Configure android-arm64 no-asm

make clean

make

您会发现.a和.so的{{1}}和libcrypto文件已放置在OpenSSL文件夹中。如果需要，请从libssl文件中删除版本后缀。

如何使用NDK 19在OSX Darwin上交叉编译适用于64位Android的OpenSSL

3 个答案: