busybox添加自定义applet

busybox添加自定义applet

本文基于：busybox-1.32.0

添加自定义applet的说明请参考busybox源码下的 docs/new_applet-HOWTO.txt 文档

1. 创建applet目录并编写代码

~/projects/busybox-1.32.0$ mkdir myapp
~/projects/busybox-1.32.0$ cd myapp
~/projects/busybox-1.32.0/myapp$ vi myapp.c

myapp.c

#include "busybox.h"

int myapp_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
int myapp_main(int argc, char *argv[])
{
        printf("Hello myapp!!!\n");
        return 0;
}

Config.src 

menu "Myapp"

config MYAPP
        bool "my app"
        default y
        select PLATFORM_LINUX
        help
                This is a demo app

INSERT

endmenu

添加完该文件的目的是在make menuconfig菜单里能够看到myapp选项，并在.config文件里生成对应的CONFIG_MYAPP=y。

到目前为止，make还无法知道myapp.c的存在，需要添加Kbuild.src文件并将myapp加入其中：

Kbuild.src

lib-y:=

lib-$(CONFIG_MYAPP) += myapp.o

INSERT

2. 将myapp添加到Makefile

步骤1只是完成了myapp代码及编译相关文件的编写，但并未告知到busybox的Makefiel, 所以我们要讲步骤1中新增的myapp加入到Makefile：

~/tools/busybox-1.32.0$ vi Makefile

~/tools/busybox-1.32.0$ vi Config.in

3. 在include/usage.src.h 中增加相应的 usage 说明

~/tools/busybox-1.32.0$ git diff  include/usage.src.h
diff --git a/include/usage.src.h b/include/usage.src.h
index d22efd3..e2d12ad 100644
--- a/include/usage.src.h
+++ b/include/usage.src.h
@@ -25,6 +25,9 @@
        " (default "CONFIG_FEATURE_DEFAULT_PASSWD_ALGO")"
 #endif

+#define myapp_trivial_usage "None"
+#define myapp_full_usage "None"
+
 INSERT

 #define busybox_notes_usage \

4. 在 include/applets.src.h中增加相应的 applet

~/tools/busybox-1.32.0$ git diff include/applets.src.h
diff --git a/include/applets.src.h b/include/applets.src.h
index 60968ce..e39a13e 100644
--- a/include/applets.src.h
+++ b/include/applets.src.h
@@ -85,6 +85,7 @@ s     - suid type:
 # define BB_DIR_USR_SBIN BB_DIR_SBIN
 #endif

+IF_MYAPP(APPLET(myapp, BB_DIR_SBIN, BB_SUID_DROP))

 INSERT

 这会在对应的include/applets.h文件中生成myapp相关的信息：

5. 编译生成myapp

先make menuconfig

 生成新的.config文件，该文件里会包含：

CONFIG_MYAPP=y

再make && make install即可生成myapp.

~/tools/busybox-1.32.0/_install/sbin$ ll myapp
lrwxrwxrwx 1 zhangsan zhangsan 14 Sep 11 13:38 myapp -> ../bin/busybox*

6. 运行myapp

 

参考：如何向busybox添加自己的命令