由于项目需要在NDK中使用网络开发,对于c语言网络开发来说,libcurl库是个很不错的选择,但android系统中并没有自带该库,所以就得自己移植了。
下面是移植步骤:
1. 下载curl源码
我这里下载的是curl-7.22.0,源码下载地址为:http://curl.haxx.se/download.html
2. 准备android源码编译环境,
android源码应已全部编译过,具体细节这里不详述,我这里使用的是android2.2 froyo源码树。
3. 在android中编译curl
在最新的curl源码里其实已经带有Android.mk这个编译文件了,而且在这文件的开头注释部分比较详细地介绍编译方法。
1)拷贝curl源码至android源码树下的external/curl
2)cd 到 external/curl目录下,输入(红色字部分根据自己的环境做相应的更改):
ANDROID_HOME=/home/braincol/workspace/android/froyo && \
NDK_HOME=/home/braincol/workspace/android/froyo/ndk && \
PATH="$ANDROID_HOME/prebuilt/linux-x86/toolchain/arm-eabi-4.4.0/bin:$PATH" \
./configure --host=arm-linux CC=arm-eabi-gcc --with-random=/dev/urandom \
CPPFLAGS="-I$NDK_HOME/platforms/android-8/arch-arm/usr/include \
-I $ANDROID_HOME/external/curl/include/ \
-I $ANDROID_HOME/external/curl/3rd/include \
-I $ANDROID_HOME/external/curl \
-I $ANDROID_HOME/out/target/product/generic/obj/STATIC_LIBRARIES/libcurl_intermediates \
-I $ANDROID_HOME/dalvik/libnativehelper/include/nativehelper \
-I $ANDROID_HOME/system/core/include \
-I $ANDROID_HOME/hardware/libhardware/include \
-I $ANDROID_HOME/hardware/libhardware_legacy/include \
-I $ANDROID_HOME/hardware/ril/include \
-I $ANDROID_HOME/dalvik/libnativehelper/include \
-I $ANDROID_HOME/frameworks/base/include \
-I $ANDROID_HOME/frameworks/base/opengl/include \
-I $ANDROID_HOME/frameworks/base/native/include \
-I $ANDROID_HOME/external/skia/include \
-I $ANDROID_HOME/out/target/product/generic/obj/include \
-I $ANDROID_HOME/bionic/libc/arch-arm/include \
-I $ANDROID_HOME/bionic/libc/include \
-I $ANDROID_HOME/bionic/libstdc++/include \
-I $ANDROID_HOME/bionic/libc/kernel/common \
-I $ANDROID_HOME/bionic/libc/kernel/arch-arm \
-I $ANDROID_HOME/bionic/libm/include \
-I $ANDROID_HOME/bionic/libm/include/arch/arm \
-I $ANDROID_HOME/bionic/libthread_db/include \
-include $ANDROID_HOME/system/core/include/arch/linux-arm/AndroidConfig.h \
-I $ANDROID_HOME/system/core/include/arch/linux-arm/ \
-D__ARM_ARCH_5__ -D__ARM_ARCH_5T__ -D__ARM_ARCH_5E__ -D__ARM_ARCH_5TE__ -DANDROID -DNDEBUG -DNDEBUG -DHAVE_CONFIG_H" \
CFLAGS="-fno-exceptions -Wno-multichar -msoft-float -fpic -ffunction-sections \
-funwind-tables -fstack-protector -Wa,--noexecstack -Werror=format-security \
-fno-short-enums -march=armv5te -mtune=xscale -Wno-psabi -mthumb-interwork \
-fmessage-length=0 -W -Wall -Wno-unused -Winit-self -Wpointer-arith \
-Werror=return-type -Werror=non-virtual-dtor -Werror=address -Werror=sequence-point \
-g -Wstrict-aliasing=2 -finline-functions -fno-inline-functions-called-once \
-fgcse-after-reload -frerun-cse-after-loop -frename-registers -UDEBUG \
-mthumb -Os -fomit-frame-pointer -fno-strict-aliasing -finline-limit=64 \
-Wpointer-arith -Wwrite-strings -Wunused -Winline -Wnested-externs \
-Wmissing-declarations -Wmissing-prototypes -Wno-long-long -Wfloat-equal \
-Wno-multichar -Wsign-compare -Wno-format-nonliteral -Wendif-labels \
-Wstrict-prototypes -Wdeclaration-after-statement -Wno-system-headers" \
LIBS="-nostdlib -Bdynamic -Wl,-T,$ANDROID_HOME/build/core/armelf.x \
-Wl,-dynamic-linker,/system/bin/linker -Wl,--gc-sections -Wl,-z,nocopyreloc \
-L$ANDROID_HOME/out/target/product/generic/obj/lib -Wl,-z,noexecstack \
-Wl,-rpath-link=$ANDROID_HOME/out/target/product/generic/obj/lib \
-lc -llog -lcutils -lstdc++ \
-Wl,--no-undefined $ANDROID_HOME/prebuilt/linux-x86/toolchain/arm-eabi-4.4.0/lib/gcc/arm-eabi/4.4.0/libgcc.a \
$ANDROID_HOME/out/target/product/generic/obj/lib/crtend_android.o \
-lm $ANDROID_HOME/out/target/product/generic/obj/lib/crtbegin_dynamic.o \
-L$ANDROID_HOME/external/curl/3rd/libs"
如果$ANDROID_HOME目录下没有ndk的开发包,那么到google的官网上下载一个放进去就行了。
3)cd 到源码根目录 mmm extern/libcurl:
编译完成之后,会生成静态库:out/target/product/generic/obj/STATIC_LIBRARIES/libcurl_intermediates/libcurl.a 。
4)如果要生成动态库需要修改curl下的Android.mk :
LOCAL_PRELINK_MODULE := false
LOCAL_MODULE:= libcurl
LOCAL_MODULE_TAGS := optional
# Copy the licence to a place where Android will find it.
# Actually, this doesn't quite work because the build system searches
# for NOTICE files before it gets to this point, so it will only be seen
# on subsequent builds.
ALL_PREBUILT += $(LOCAL_PATH)/NOTICE
$(LOCAL_PATH)/NOTICE: $(LOCAL_PATH)/COPYING | $(ACP)
$(copy-file-to-target)
#include $(BUILD_STATIC_LIBRARY)
include $(BUILD_SHARED_LIBRARY)
4. 在android中测试curl
1)在android froyo源码树中下建立一个mytest目录,该目录下再建立一个curltest目录。
2)在目录curtest下创建curl-test.cpp:
#include "curl/curl.h" #include <stdio.h>; int main() { CURL *curl; CURLcode res; curl_global_init(CURL_GLOBAL_ALL); curl = curl_easy_init(); if (curl) { curl_easy_setopt(curl, CURLOPT_URL, "http://www.cnblogs.com/hibraincol/"); res = curl_easy_perform(curl); if (0!=res) { printf("curl error: %d\n", res); } curl_easy_cleanup(curl); } curl_global_cleanup(); return 0; }
3)在目录curtest下创建Android.mk:
# curl test executable # LOCAL_PATH := $(call my-dir) include $(CLEAR_VARS) LOCAL_C_INCLUDES += \ $(LOCAL_PATH)/3rd/include LOCAL_SRC_FILES:= curl-test.cpp # No shared libraries. LOCAL_SHARED_LIBRARIES := # No static libraries. LOCAL_STATIC_LIBRARIES := libcurl LOCAL_MODULE := curl-test include $(BUILD_EXECUTABLE)
4)把libcurl的头文件拷贝到curtest目录下的3rd/include目录下:
cp -rf out/target/product/generic/obj/include/libcurl/curl mytest/curltest/3rd/include
5)到android源码树的根目录下:mmm /mytest/curltest/
braincol@ubuntu:~/workspace/android/froyo$ mmm mytest/curltest/
============================================
PLATFORM_VERSION_CODENAME=REL
PLATFORM_VERSION=2.2
TARGET_PRODUCT=generic
TARGET_BUILD_VARIANT=eng
TARGET_SIMULATOR=
TARGET_BUILD_TYPE=release
TARGET_BUILD_APPS=
TARGET_ARCH=arm
HOST_ARCH=x86
HOST_OS=linux
HOST_BUILD_TYPE=release
BUILD_ID=MASTER
============================================
make: Entering directory `/home/braincol/workspace/android/froyo'
target thumb C++: curl-test <= mytest/curltest/curl-test.cpp
mytest/curltest/curl-test.cpp:2:19: warning: extra tokens at end of #include directive
target Executable: curl-test (out/target/product/generic/obj/EXECUTABLES/curl-test_intermediates/LINKED/curl-test)
target Non-prelinked: curl-test (out/target/product/generic/symbols/system/bin/curl-test)
target Strip: curl-test (out/target/product/generic/obj/EXECUTABLES/curl-test_intermediates/curl-test)
Install: out/target/product/generic/system/bin/curl-test
make: Leaving directory `/home/braincol/workspace/android/froyo'
可以看到在out/target/product/generic/system/bin/下生成了curl-test这个测试程序。
6)将curl-test拷贝到真机或者模拟器中运行。
a.我这里是在android真机的根目录下建立了一个test目录.
b.然后通过adb push将curl-test拷贝到该目录下,并更改curl-test为可执行权限:chmod 777 curl-test.
c. adb shell 进入shell控制台,然后cd到test目录下, ./curl-test 执行,可以看到打印出的网页源码,移植成功。
这样在之后的android app开发中,如果需要用到libcurl的库,就可以直接out/target/product/generic/obj/include/libcurl/curl里的头文件和out/target/product/generic/obj/STATIC_LIBRARIES/libcurl_intermediates/libcurl.a拿到app工程中去用就行了。