一步一步寫一個簡單通用的makefile(四)--寫一個通用的makefile編譯android可執行文件

通常要把我們自己的的代碼編譯成在android里面編譯的可執行文件，我們通常是建一個文件夾

.
├── Android.mk
├── Application.mk
├── convolve.cl
├── convolve_cl.cpp
├── convolve_cl.cpp~
├── inter_ocl
│   └── opencl
│       ├── CL
│       │   ├── cl_ext.h
│       │   ├── cl.h
│       │   ├── cl_platform.h
│       │   └── opencl.h
│       ├── clew.c
│       ├── clew.h
│       ├── ocl_wrapper.c
│       └── ocl_wrapper.h
└── mylog.h

類似這樣，里面有android.mk 文件，然后進入到這個文件夾執行ndk-build,生成文件如下：

[armeabi-v7a] Install        : convolve-ocl => libs/armeabi-v7a/convolve-ocl
[armeabi-v7a] Install        : libstlport_shared.so => libs/armeabi-v7a/libstlport_shared.so

但是今天我們要修改上一章的模板makefile來編譯可以在android中執行的可執行文件。

首先我們還是用之前的三個文件hellomake.c, hellofunc.c, hellofunc.h,文件樹如下：

.
├── makefile
├── makefile1
└── src
    ├── hellofunc.c
    ├── hellofunc.h
    └── hellomake.c

因為要用到android的交叉編譯器，所以不能用gcc，另外尋找頭文件的系統路徑也不一樣，尋找庫的路徑也和linux原本的不同，所以 -I 和 -L的路徑也需要修改

修改之后的makefile如下：

#Hellomake
#Magnum， 2014-10-19
# 指令編譯器和選項
TOOLCHAINS_ROOT=$(NDK_HOME)/toolchains/arm-linux-androideabi-4.8/prebuilt/linux-x86_64/
TOOLCHAINS_PREFIX=$(TOOLCHAINS_ROOT)/bin/arm-linux-androideabi
TOOLCHAINS_INCLUDE=$(TOOLCHAINS_ROOT)/lib/gcc/arm-linux-androideabi/4.8/include-fixed

PLATFORM_ROOT=$(NDK_HOME)/platforms/android-17/arch-arm
NDKINC=$(PLATFORM_ROOT)/usr/include
NDKLIB=$(PLATFORM_ROOT)/usr/lib

CC=$(TOOLCHAINS_PREFIX)-gcc
CFLAGS=-Wall 
# 需要鏈接庫的庫名，比如libm.a，就是-lm,需要去掉前面的lib和后面的.a
LIBS=-lm 
# 設置默認搜索頭文件的路徑，優先是這個，然后是系統路徑
IncludeDir = -I./include/ -I$(NDKINC)
# 需要鏈接的庫的路徑
LinkDir = -L$(NDKINC)
OBJ_DIR = ./obj
BIN_DIR = ./bin

#PROJECT_TOP_DIR設置成pwd 或者"./"都行
PROJECT_TOP_DIR=.#$(shell pwd)#$(shell cd ../; pwd)
PROJECT_BIN_DIR=$(PROJECT_TOP_DIR)/bin
PROJECT_SRC_DIR=$(PROJECT_TOP_DIR)/src
PROJECT_LIB_DIR=$(PROJECT_TOP_DIR)/lib
PROJECT_OBJ_DIR=$(PROJECT_TOP_DIR)/objs
MKDIR := mkdir -p

# 目標文件
EXE_NAME=hellomake
TARGET=$(BIN_DIR)/$(EXE_NAME)

#源文件的文件類型
FILE_TYPE=c
src=$(wildcard $(PROJECT_SRC_DIR)/*.$(FILE_TYPE))
dir= $(notdir $(src))
PROJECT_OBJ= $(patsubst %.$(FILE_TYPE),%.o,$(dir) )
PROJECT_ALL_OBJS= $(addprefix $(PROJECT_OBJ_DIR)/, $(PROJECT_OBJ))

all: chdir $(TARGET)

$(TARGET): $(PROJECT_ALL_OBJS)
$(CC) $(CFLAGS) -o $@ $^ $(LinkDir) $(LIBS)

chdir:
@if test ! -d $(PROJECT_OBJ_DIR) ; \
then \
mkdir $(PROJECT_OBJ_DIR) ; \
fi

@if test ! -d $(PROJECT_BIN_DIR) ; \
then \
mkdir $(PROJECT_BIN_DIR) ; \
fi

.PHONY : clean
clean:
-rm -rf $(PROJECT_BIN_DIR) $(PROJECT_OBJ_DIR)

$(PROJECT_OBJ_DIR)/%.o:$(PROJECT_SRC_DIR)/%.$(FILE_TYPE)
$(CC) $(CFLAGS) -o $@ -c $< $(IncludeDir)

執行make, 報錯：

/home/magnum/work-environment/android-ndk-r9d/toolchains/arm-linux-androideabi-4.8/prebuilt/linux-x86_64//bin/arm-linux-androideabi-gcc -Wall  -o objs/hellofunc.o -c src/hellofunc.c -I./include/ -I/home/magnum/work-environment/android-ndk-r9d/platforms/android-17/arch-arm/usr/include
/home/magnum/work-environment/android-ndk-r9d/toolchains/arm-linux-androideabi-4.8/prebuilt/linux-x86_64//bin/arm-linux-androideabi-gcc -Wall  -o objs/hellomake.o -c src/hellomake.c -I./include/ -I/home/magnum/work-environment/android-ndk-r9d/platforms/android-17/arch-arm/usr/include
/home/magnum/work-environment/android-ndk-r9d/toolchains/arm-linux-androideabi-4.8/prebuilt/linux-x86_64//bin/arm-linux-androideabi-gcc -Wall  -o bin/hellomake objs/hellofunc.o objs/hellomake.o -L/home/magnum/work-environment/android-ndk-r9d/platforms/android-17/arch-arm/usr/include -lm  
/home/magnum/work-environment/android-ndk-r9d/toolchains/arm-linux-androideabi-4.8/prebuilt/linux-x86_64/bin/../lib/gcc/arm-linux-androideabi/4.8/../../../../arm-linux-androideabi/bin/ld: error: cannot open crtbegin_dynamic.o: No such file or directory
/home/magnum/work-environment/android-ndk-r9d/toolchains/arm-linux-androideabi-4.8/prebuilt/linux-x86_64/bin/../lib/gcc/arm-linux-androideabi/4.8/../../../../arm-linux-androideabi/bin/ld: error: cannot open crtend_android.o: No such file or directory
/home/magnum/work-environment/android-ndk-r9d/toolchains/arm-linux-androideabi-4.8/prebuilt/linux-x86_64/bin/../lib/gcc/arm-linux-androideabi/4.8/../../../../arm-linux-androideabi/bin/ld: error: cannot find -lm
/home/magnum/work-environment/android-ndk-r9d/toolchains/arm-linux-androideabi-4.8/prebuilt/linux-x86_64/bin/../lib/gcc/arm-linux-androideabi/4.8/../../../../arm-linux-androideabi/bin/ld: error: cannot find -lc
/home/magnum/work-environment/android-ndk-r9d/toolchains/arm-linux-androideabi-4.8/prebuilt/linux-x86_64/bin/../lib/gcc/arm-linux-androideabi/4.8/../../../../arm-linux-androideabi/bin/ld: error: cannot find -ldl
objs/hellofunc.o:hellofunc.c:function myPrintHelloMake: error: undefined reference to 'puts'
objs/hellomake.o:hellomake.c:function main: error: undefined reference to 'log'
objs/hellomake.o:hellomake.c:function main: error: undefined reference to 'printf'
collect2: error: ld returned 1 exit status
make: *** [bin/hellomake] Error 1

進入到objs目錄，發現.o文件生成成功，所以問題應該是出現在鏈接的時候。

crtbegin_dynamic.o: No such file or directory  和

crtend_android.o: No such file or directory 錯誤，

需要修改：

CFLAGS=-Wall -nostdlib .  然后執行make，錯誤只剩下：

/home/magnum/work-environment/android-ndk-r9d/toolchains/arm-linux-androideabi-4.8/prebuilt/linux-x86_64//bin/arm-linux-androideabi-gcc -Wall -nostdlib  -o bin/hellomake objs/hellofunc.o objs/hellomake.o -L/home/magnum/work-environment/android-ndk-r9d/platforms/android-17/arch-arm/usr/include -lm  
/home/magnum/work-environment/android-ndk-r9d/toolchains/arm-linux-androideabi-4.8/prebuilt/linux-x86_64/bin/../lib/gcc/arm-linux-androideabi/4.8/../../../../arm-linux-androideabi/bin/ld: error: cannot find -lm
objs/hellofunc.o:hellofunc.c:function myPrintHelloMake: error: undefined reference to 'puts'
objs/hellomake.o:hellomake.c:function main: error: undefined reference to 'log'
objs/hellomake.o:hellomake.c:function main: error: undefined reference to 'printf'
collect2: error: ld returned 1 exit status
make: *** [bin/hellomake] Error 1

不好意思，這個是因為

LinkDir = -L$(NDKINC),  這里復制后並沒有修改，應該是LinkDir = -L$(NDKLIB)，這個可以解決然后

undefined reference to 'log'

執行make，還是有一個錯誤：

/home/magnum/work-environment/android-ndk-r9d/toolchains/arm-linux-androideabi-4.8/prebuilt/linux-x86_64//bin/arm-linux-androideabi-gcc -Wall -nostdlib  -o objs/hellofunc.o -c src/hellofunc.c -I./include/ -I/home/magnum/work-environment/android-ndk-r9d/platforms/android-17/arch-arm/usr/include
/home/magnum/work-environment/android-ndk-r9d/toolchains/arm-linux-androideabi-4.8/prebuilt/linux-x86_64//bin/arm-linux-androideabi-gcc -Wall -nostdlib  -o objs/hellomake.o -c src/hellomake.c -I./include/ -I/home/magnum/work-environment/android-ndk-r9d/platforms/android-17/arch-arm/usr/include
/home/magnum/work-environment/android-ndk-r9d/toolchains/arm-linux-androideabi-4.8/prebuilt/linux-x86_64//bin/arm-linux-androideabi-gcc -Wall -nostdlib  -o bin/hellomake objs/hellofunc.o objs/hellomake.o -L/home/magnum/work-environment/android-ndk-r9d/platforms/android-17/arch-arm/usr/lib -lm -ldl  
objs/hellofunc.o:hellofunc.c:function myPrintHelloMake: error: undefined reference to 'puts'
objs/hellomake.o:hellomake.c:function main: error: undefined reference to 'printf'

修改LIBS=-lm  更改為：LIBS=-lm -lc  再次執行make, 編譯成功，

adb push ./bin/hellomake /data/local/tmp;

然后執行：

adb shell  /data/local/tmp/hellomake, 奇怪沒有任何輸出，需要修改：

PROJECT_ALL_OBJS+=$(NDKLIB)/crtbegin_dynamic.o
PROJECT_ALL_OBJS+=$(NDKLIB)/crtend_android.o

然后從新編譯，push,執行得到：

Hello makefiles!
Value:2.708050

 好啦，完成

最后的makefile是：

#Hellomake
#Magnum， 2014-10-19
# 指令編譯器和選項
TOOLCHAINS_ROOT=$(NDK_HOME)/toolchains/arm-linux-androideabi-4.8/prebuilt/linux-x86_64/
TOOLCHAINS_PREFIX=$(TOOLCHAINS_ROOT)/bin/arm-linux-androideabi
TOOLCHAINS_INCLUDE=$(TOOLCHAINS_ROOT)/lib/gcc/arm-linux-androideabi/4.8/include-fixed

PLATFORM_ROOT=$(NDK_HOME)/platforms/android-17/arch-arm
NDKINC=$(PLATFORM_ROOT)/usr/include
NDKLIB=$(PLATFORM_ROOT)/usr/lib

CC=$(TOOLCHAINS_PREFIX)-gcc
CFLAGS=-Wall -nostdlib #-Bdynamic
# 需要鏈接庫的庫名，比如libm.a，就是-lm,需要去掉前面的lib和后面的.a
LIBS=-lm -lc #-lgcc
# 設置默認搜索頭文件的路徑，優先是這個，然后是系統路徑
IncludeDir = -I./include/ -I$(NDKINC)
# 需要鏈接的庫的路徑
LinkDir = -L$(NDKLIB)
OBJ_DIR = ./obj
BIN_DIR = ./bin

#PROJECT_TOP_DIR設置成pwd 或者"./"都行
PROJECT_TOP_DIR=.#$(shell pwd)#$(shell cd ../; pwd)
PROJECT_BIN_DIR=$(PROJECT_TOP_DIR)/bin
PROJECT_SRC_DIR=$(PROJECT_TOP_DIR)/src
PROJECT_LIB_DIR=$(PROJECT_TOP_DIR)/lib
PROJECT_OBJ_DIR=$(PROJECT_TOP_DIR)/objs
MKDIR := mkdir -p

# 目標文件
EXE_NAME=hellomake
TARGET=$(BIN_DIR)/$(EXE_NAME)

#源文件的文件類型
FILE_TYPE=c
src=$(wildcard $(PROJECT_SRC_DIR)/*.$(FILE_TYPE))
dir= $(notdir $(src))
PROJECT_OBJ= $(patsubst %.$(FILE_TYPE),%.o,$(dir) )
PROJECT_ALL_OBJS= $(addprefix $(PROJECT_OBJ_DIR)/, $(PROJECT_OBJ))
PROJECT_ALL_OBJS+=$(NDKLIB)/crtbegin_dynamic.o
PROJECT_ALL_OBJS+=$(NDKLIB)/crtend_android.o

all: chdir $(TARGET)

$(TARGET): $(PROJECT_ALL_OBJS)
$(CC) $(CFLAGS) -o $@ $^ $(LinkDir) $(LIBS)

chdir:
@if test ! -d $(PROJECT_OBJ_DIR) ; \
then \
mkdir $(PROJECT_OBJ_DIR) ; \
fi

@if test ! -d $(PROJECT_BIN_DIR) ; \
then \
mkdir $(PROJECT_BIN_DIR) ; \
fi

.PHONY : clean
clean:
-rm -rf $(PROJECT_BIN_DIR) $(PROJECT_OBJ_DIR)

$(PROJECT_OBJ_DIR)/%.o:$(PROJECT_SRC_DIR)/%.$(FILE_TYPE)
$(CC) $(CFLAGS) -o $@ -c $< $(IncludeDir)

后面要把一些代碼編譯成可執行文件在android設備上驗證，用這個makefile即可。
如有寫的不符合指出，還望大家指出，共同進步