openwrt安装包编译

1、建立编译目录

helloworld/
├── Makefile
└── src
    ├── helloworld.c
    └── Makefile

在package目录下建立helloworld目录，helloworld下建立src目录

cd package
mkdir helloworld
cd helloworld
mkdir src
cd src

2、新建源代码和编译脚本

vi helloworld.c
#include <stdio.h>
#include <unistd.h>
int main(void)
{
     printf("Hell! O' world, why won't my code compile?\n\n");
     return 0;
}

vi Makefile
# build helloworld executable when user executes "make"
helloworld: helloworld.o
	$(CC) $(LDFLAGS) helloworld.o -o helloworld
helloworld.o: helloworld.c
	$(CC) $(CFLAGS) -c helloworld.c
# remove object files and executable when user executes "make clean"
clean:
	rm *.o helloworld

cd ..
vi Makefile
##############################################
# OpenWrt Makefile for HelloWorld program
#
#
# Most of the variables used here are defined in
# the include directives below. We just need to
# specify a basic description of the package,
# where to build our program, where to find
# the source files, and where to install the
# compiled program on the router.
#
# Be very careful of spacing in this file.
# Indents should be tabs, not spaces, and
# there should be no trailing whitespace in
# lines that are not commented.
#
##############################################
#TOPDIR := ../../
include $(TOPDIR)/rules.mk
# Name and release number of this package
PKG_NAME:=helloworld
PKG_RELEASE:=1


# This specifies the directory where we're going to build the program. 
# The root build directory, $(BUILD_DIR), is by default the build_mipsel
# directory in your OpenWrt SDK directory
PKG_BUILD_DIR := $(BUILD_DIR)/$(PKG_NAME)


include $(INCLUDE_DIR)/package.mk
 
# Specify package information for this program.
# The variables defined here should be self explanatory.
# If you are running Kamikaze, delete the DESCRIPTION
# variable below and uncomment the Kamikaze define
# directive for the description below
define Package/helloworld
	SECTION:=utils
	CATEGORY:=Utilities
	TITLE:=helloworld -- prints a snarky message
endef


# Uncomment portion below for Kamikaze and delete DESCRIPTION variable above
define Package/helloworld/description
	If you can't figure out what this program does, you're probably brain-de
ad and need immediate medical attention.
endef
 
# Specify what needs to be done to prepare for building the package.
# In our case, we need to copy the source files to the build directory.
# This is NOT the default.  The default uses the PKG_SOURCE_URL and the
# PKG_SOURCE which is not defined here to download the source from the web.
# In order to just build a simple program that we have just written, it is
# much easier to do it this way.
define Build/Prepare
	mkdir -p $(PKG_BUILD_DIR)
	$(CP) ./src/* $(PKG_BUILD_DIR)/
endef


# We do not need to define Build/Configure or Build/Compile directives
# The defaults are appropriate for compiling a simple program such as this one


# Specify where and how to install the program. Since we only have one file,
# the HelloWorld executable, install it by copying it to the /bin directory on
# the router. The $(1) variable represents the root directory on the router runn
ing
# OpenWrt. The $(INSTALL_DIR) variable contains a command to prepare the install
# directory if it does not already exist.  Likewise $(INSTALL_BIN) contains the
# command to copy the binary file from its current location (in our case the bui
ld
# directory) to the install directory.
define Package/helloworld/install
	$(INSTALL_DIR) $(1)/bin
	$(INSTALL_BIN) $(PKG_BUILD_DIR)/helloworld $(1)/bin/
endef


# This line executes the necessary commands to compile our program.
# The above define directives specify all the information needed, but this
# line calls BuildPackage which in turn actually uses this information to
# build a package.
$(eval $(call BuildPackage,helloworld))

ps：注意Makefile的命令前为tab，而不是空格

3、回到主目录下修改menuconfig

make menuconfig

在Utilities下勾选helloworld

4、编译

make V=s

or    make package/helloworld/compile V=s

之后可以看到生成的安装包./bin/packages/i386_pentium4/base/helloworld_1_i386_pentium4.ipk