2014年开源夏令营-android下编译libusb和libhackrf
libhackrf是上层应用程序操作hackrf的入口库，是软件操作硬件的中间件，在android上使用hackrf当然也需要使用libhackrf。操作系统与hackrf之间的通信是通过USB2.0完成的，libhackrf使用了libusb进行USB通信。android并没有自带libusb，所以我们需要自行编译。
整体分为两个部分，首先是libusb的编译，然后是libhackrf的编译。
libusb
libusb的编译十分简单，因为其没有过多的依赖，而麻烦的是android对usb权限的控制，解决权限问题有两种方法，第一种是改造libusb，并在android应用层获取usb的权限将usb的信息传到libusb。第二种是通过修改系统权限列表，使得当前程序在系统usb用户组中。我这里为了更少的更改libusb和libhackrf文件，就选用了第二种方法。以下为libusb的编译步骤
1）确保NDK安装成功，可通过在cmd中运行ndk-build --version查看信息。
C:\Users\XXXX>ndk-build --version
GNU Make 3.81
Copyright (C) 2006 Free Software Foundation, Inc.
This is free software; see the source for copying conditions.
There is NO warranty; not even for MERCHANTABILITY or FITNESS FOR A
PARTICULAR PURPOSE.
This program built for i586-pc-mingw323）加压libusb后在源码根目录创建android文件夹和相应文件。
|- libusb-master
|- android
|- jni
|- Android.mk
|- Application.mk
|- examples.mk
|- libusb.mk
|- tests.mk
|- libs
|- obj
|- config.h
|- libusb
...
文件如下:
config.h
/* Start with debug message logging enabled */
/* #undef ENABLE_DEBUG_LOGGING */
/* Message logging */
#define ENABLE_LOGGING
/* Define to 1 if you have the header file. */
#define HAVE_DLFCN_H 1
/* Define to 1 if you have the `gettimeofday' function. */
#define HAVE_GETTIMEOFDAY 1
/* Define to 1 if you have the header file. */
#define HAVE_INTTYPES_H 1
/* Linux backend */
#define OS_LINUX 1
/* Enable output to system log */
#define USE_SYSTEM_LOGGING_FACILITY 1
/* type of second poll() argument */
#define POLL_NFDS_TYPE nfds_t
/* Use POSIX Threads */
#define THREADS_POSIX 1
/* Default visibility */
#define DEFAULT_VISIBILITY __attribute__((visibility("default")))
/* Define to 1 if you have the header file. */
#define HAVE_MEMORY_H 1
/* Define to 1 if you have the header file. */
#define HAVE_POLL_H 1
/* Define to 1 if you have the header file. */
#define HAVE_SIGNAL_H 1
/* Define to 1 if you have the header file. */
#define HAVE_SYS_STAT_H 1
/* Define to 1 if you have the header file. */
#define HAVE_SYS_TIME_H 1
/* Define to 1 if you have the header file. */
#define HAVE_SYS_TYPES_H 1
/* Define to 1 if you have the header file. */
#define HAVE_UNISTD_H 1
/* Define to 1 if you have the header file. */
#define HAVE_LINUX_FILTER_H 1
/* Define to 1 if you have the header file. */
#define HAVE_LINUX_NETLINK_H 1
/* Define to 1 if you have the header file. */
#define HAVE_ASM_TYPES_H 1
/* Define to 1 if you have the header file. */
#define HAVE_SYS_SOCKET_H 1
LOCAL_PATH:= $(call my-dir)
include $(LOCAL_PATH)/libusb.mk
include $(LOCAL_PATH)/examples.mk
include $(LOCAL_PATH)/tests.mk
Application.mk
APP_ABI := all
APP_LDFLAGS := -llog# Android build config for libusb examples
# Copyright © 2012-2013 RealVNC Ltd.
#
# This library is free software; you can redistribute it and/or
# modify it under the terms of the GNU Lesser General Public
# License as published by the Free Software Foundation; either
# version 2.1 of the License, or (at your option) any later version.
#
# This library is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
# Lesser General Public License for more details.
#
# You should have received a copy of the GNU Lesser General Public
# License along with this library; if not, write to the Free Software
# Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
#
LOCAL_PATH:= $(call my-dir)
LIBUSB_ROOT_REL:= ../..
LIBUSB_ROOT_ABS:= $(LOCAL_PATH)/../..
# listdevs
include $(CLEAR_VARS)
LOCAL_SRC_FILES := \
$(LIBUSB_ROOT_REL)/examples/listdevs.c
LOCAL_C_INCLUDES += \
$(LIBUSB_ROOT_ABS)
LOCAL_SHARED_LIBRARIES += libusb1.0
LOCAL_MODULE:= listdevs
include $(BUILD_EXECUTABLE)
# xusb
include $(CLEAR_VARS)
LOCAL_SRC_FILES := \
$(LIBUSB_ROOT_REL)/examples/xusb.c
LOCAL_C_INCLUDES += \
$(LIBUSB_ROOT_ABS)
LOCAL_SHARED_LIBRARIES += libusb1.0
LOCAL_MODULE:= xusb
include $(BUILD_EXECUTABLE)
# hotplugtest
include $(CLEAR_VARS)
LOCAL_SRC_FILES := \
$(LIBUSB_ROOT_REL)/examples/hotplugtest.c
LOCAL_C_INCLUDES += \
$(LIBUSB_ROOT_ABS)
LOCAL_SHARED_LIBRARIES += libusb1.0
LOCAL_MODULE:= hotplugtest
include $(BUILD_EXECUTABLE)
# fxload
include $(CLEAR_VARS)
LOCAL_SRC_FILES := \
$(LIBUSB_ROOT_REL)/examples/fxload.c \
$(LIBUSB_ROOT_REL)/examples/ezusb.c
LOCAL_C_INCLUDES += \
$(LIBUSB_ROOT_ABS)
LOCAL_SHARED_LIBRARIES += libusb1.0
LOCAL_MODULE:= fxload
include $(BUILD_EXECUTABLE)
# sam3u_benchmake
include $(CLEAR_VARS)
LOCAL_SRC_FILES := \
$(LIBUSB_ROOT_REL)/examples/sam3u_benchmark.c
LOCAL_C_INCLUDES += \
$(LIBUSB_ROOT_ABS)
LOCAL_SHARED_LIBRARIES += libusb1.0
LOCAL_MODULE:= sam3u_benchmark
include $(BUILD_EXECUTABLE)
# dpfp
include $(CLEAR_VARS)
LOCAL_SRC_FILES := \
$(LIBUSB_ROOT_REL)/examples/dpfp.c
LOCAL_C_INCLUDES += \
$(LIBUSB_ROOT_ABS)
LOCAL_SHARED_LIBRARIES += libusb1.0
LOCAL_MODULE:= dpfp
include $(BUILD_EXECUTABLE)
# dpfp_threaded
include $(CLEAR_VARS)
LOCAL_SRC_FILES := \
$(LIBUSB_ROOT_REL)/examples/dpfp_threaded.c
LOCAL_C_INCLUDES += \
$(LIBUSB_ROOT_ABS)
LOCAL_SHARED_LIBRARIES += libusb1.0
LOCAL_MODULE:= dpfp_threaded
include $(BUILD_EXECUTABLE)
libusb.mk
# Android build config for libusb
# Copyright © 2012-2013 RealVNC Ltd.
#
# This library is free software; you can redistribute it and/or
# modify it under the terms of the GNU Lesser General Public
# License as published by the Free Software Foundation; either
# version 2.1 of the License, or (at your option) any later version.
#
# This library is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
# Lesser General Public License for more details.
#
# You should have received a copy of the GNU Lesser General Public
# License along with this library; if not, write to the Free Software
# Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
#
LOCAL_PATH:= $(call my-dir)
LIBUSB_ROOT_REL:= ../..
LIBUSB_ROOT_ABS:= $(LOCAL_PATH)/../..
# libusb
include $(CLEAR_VARS)
LIBUSB_ROOT_REL:= ../..
LIBUSB_ROOT_ABS:= $(LOCAL_PATH)/../..
LOCAL_SRC_FILES := \
$(LIBUSB_ROOT_REL)/libusb/core.c \
$(LIBUSB_ROOT_REL)/libusb/descriptor.c \
$(LIBUSB_ROOT_REL)/libusb/hotplug.c \
$(LIBUSB_ROOT_REL)/libusb/io.c \
$(LIBUSB_ROOT_REL)/libusb/sync.c \
$(LIBUSB_ROOT_REL)/libusb/strerror.c \
$(LIBUSB_ROOT_REL)/libusb/os/linux_usbfs.c \
$(LIBUSB_ROOT_REL)/libusb/os/poll_posix.c \
$(LIBUSB_ROOT_REL)/libusb/os/threads_posix.c \
$(LIBUSB_ROOT_REL)/libusb/os/linux_netlink.c
LOCAL_C_INCLUDES += \
$(LOCAL_PATH)/.. \
$(LIBUSB_ROOT_ABS)/libusb \
$(LIBUSB_ROOT_ABS)/libusb/os
LOCAL_EXPORT_C_INCLUDES := \
$(LIBUSB_ROOT_ABS)/libusb
LOCAL_LDLIBS := -llog
LOCAL_MODULE := libusb1.0
include $(BUILD_SHARED_LIBRARY)
tests.mk
# Android build config for libusb tests
# Copyright © 2012-2013 RealVNC Ltd.
#
# This library is free software; you can redistribute it and/or
# modify it under the terms of the GNU Lesser General Public
# License as published by the Free Software Foundation; either
# version 2.1 of the License, or (at your option) any later version.
#
# This library is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
# Lesser General Public License for more details.
#
# You should have received a copy of the GNU Lesser General Public
# License along with this library; if not, write to the Free Software
# Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
#
LOCAL_PATH:= $(call my-dir)
LIBUSB_ROOT_REL:= ../..
LIBUSB_ROOT_ABS:= $(LOCAL_PATH)/../..
# testlib
include $(CLEAR_VARS)
LOCAL_SRC_FILES := \
$(LIBUSB_ROOT_REL)/tests/testlib.c
LOCAL_C_INCLUDES += \
$(LIBUSB_ROOT_ABS)/tests
LOCAL_EXPORT_C_INCLUDES := \
$(LIBUSB_ROOT_ABS)/tests
LOCAL_MODULE := testlib
include $(BUILD_STATIC_LIBRARY)
# stress
include $(CLEAR_VARS)
LOCAL_SRC_FILES := \
$(LIBUSB_ROOT_REL)/tests/stress.c
LOCAL_C_INCLUDES += \
$(LIBUSB_ROOT_ABS)
LOCAL_SHARED_LIBRARIES += libusb1.0
LOCAL_STATIC_LIBRARIES += testlib
LOCAL_MODULE:= stress
include $(BUILD_EXECUTABLE)
4）切换到android目录，使用ndk-build进行编译
编译完成之后，可以在libs文件夹下看到不同平台的lib和可执行文件，拷贝即可使用。
libhackrf
libhackrf的编译，可以参照libusb的编译。在hackrf-master\host\libhackrf\src下创建如下结构
|- android/
|- jni/
|- Android.mk
|- Application.mk
|- libhackrf.mk
|- libs/
|- obj/
Android.mk
LOCAL_PATH:= $(call my-dir)
include $(LOCAL_PATH)/libhackrf.mk
include $(LOCAL_PATH)/../../libusb/Android.mkApplication.mk
APP_ABI := armeabi armeabi-v7a
APP_LDFLAGS := -lloglibhackrf.mk
# Android build config for libhackrf
# Copyright © 2014
#
# This library is free software; you can redistribute it and/or
# modify it under the terms of the GNU Lesser General Public
# License as published by the Free Software Foundation; either
# version 2.1 of the License, or (at your option) any later version.
#
# This library is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
# Lesser General Public License for more details.
#
LOCAL_PATH:= $(call my-dir)
LIBUSB_ROOT_REL:= ../..
LIBUSB_ROOT_ABS:= $(LOCAL_PATH)/../..
# libhackrf
#D:\dev\android-ndk-r9d\ndk-build
include $(CLEAR_VARS)
LOCAL_SRC_FILES := $(LIBUSB_ROOT_REL)/hackrf.c
LOCAL_C_INCLUDES += $(LIBUSB_ROOT_ABS)/ \
$(LIBUSB_ROOT_ABS)/libusb/
LOCAL_LDLIBS := -llog
LOCAL_MODULE := libhackrf
LOCAL_SHARED_LIBRARIES += libusb1.0
include $(BUILD_SHARED_LIBRARY)
4）切换到android目录，使用ndk-build进行编译
总体编译完成后，即可得到libhackrf.so和libusb.so以及对映的头文件，可以拷贝到android中使用。