android ndk 编译 libevent

1. 下载 libevent 2.1.8 版本

   https://github.com/libevent/libevent/releases/download/release-2.1.8-stable/libevent-2.1.8-stable.tar.gz

2. 先在 win10 上用 wsl ubuntu 编译 libevent

3. 在 wsl 上，准备需要的编译环境

sudo apt-get install automake
sudo apt-get install autoconf
sudo apt-get install libtool

4. 在livevent目录下运行 autogen.sh

./autogen.sh

autoreconf: Entering directory `.'
autoreconf: configure.ac: not using Gettext
autoreconf: running: aclocal --force -I m4
autoreconf: configure.ac: tracing
autoreconf: running: libtoolize --copy --force
libtoolize: putting auxiliary files in '.'.
libtoolize: copying file './ltmain.sh'
libtoolize: putting macros in AC_CONFIG_MACRO_DIRS, 'm4'.
libtoolize: copying file 'm4/libtool.m4'
libtoolize: copying file 'm4/ltoptions.m4'
libtoolize: copying file 'm4/ltsugar.m4'
libtoolize: copying file 'm4/ltversion.m4'
libtoolize: copying file 'm4/lt~obsolete.m4'
autoreconf: running: /usr/bin/autoconf --force
autoreconf: running: /usr/bin/autoheader --force
autoreconf: running: automake --add-missing --copy --force-missing
configure.ac:25: installing './compile'
configure.ac:13: installing './missing'
Makefile.am: installing './depcomp'
autoreconf: Leaving directory `.'

5. ./configure

6. make

至此在 wsl ubuntu 上编译libevent已经完成了

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下面，就需要在android ndk 环境下编译

1. 在windows上，下载最新版本的ndk

2. 编写 Android.mk

LOCAL_PATH := $(call my-dir)
include $(CLEAR_VARS)
LOCAL_ARM_MODE := arm
LOCAL_MODULE := libevent
LIB_SRC := event.c \
           evthread.c \
           buffer.c \
           bufferevent.c \
           bufferevent_filter.c \
           bufferevent_pair.c \
           listener.c \
           bufferevent_ratelim.c \
           evmap.c \
           log.c \
           evutil.c \
           evutil_rand.c \
           select.c \
           poll.c \
           epoll.c \
           signal.c \
           event_tagging.c \
           http.c \
           evdns.c \
           evrpc.c \
           bufferevent_sock.c

LOCAL_SRC_FILES  := $(LIB_SRC)
LOCAL_C_INCLUDES := $(LOCAL_PATH)/include \
                    $(LOCAL_PATH)/compat
LOCAL_CFLAGS += -pie -fPIE -static -fPIC
include $(BUILD_STATIC_LIBRARY)

3. 编译 Application.mk

APP_STL      := c++_static
APP_CPPFLAGS := -frtti -std=c++11
APP_ABI      := armeabi-v7a arm64-v8a x86
#APP_ABI     := armeabi-v7a

4. 调用 ndk-build.cmd 就可以编译了

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编译过程中遇到的问题, 需要修改 ./include/event2/event-config.h 中的定义

1. error: 'sys/sysctl.h' file not found

   注释定义  #define EVENT__HAVE_SYS_SYSCTL_H 1

2. error: static declaration of 'arc4random_addrandom' follows non-static declaration

   增加定义  #define EVENT__HAVE_ARC4RANDOM 1

3. error: use of undeclared identifier 'fd_mask'

   注释定义  #define EVENT__HAVE_FD_MASK 1

4. error: 'sys/timerfd.h' file not found

   注释定义  #define EVENT__HAVE_SYS_TIMERFD_H 1

5. error: use of undeclared identifier 'EPOLL_CLOEXEC'

   注释定义  #define EVENT__HAVE_EPOLL_CREATE1 1

基本上就对event-config.h中的一些配置做调整就可以在ndk环境当中编译了，非常简单！