VTYSH命令

DEFPY

定义

#define DEFPY(funcname, cmdname, cmdstr, helpstr)                              \
	DEFUN_CMD_ELEMENT(funcname, cmdname, cmdstr, helpstr, 0, 0)            \
	funcdecl_##funcname

cmdname 结构体定义、初始化

/* helper defines for end-user DEFUN* macros */
#define DEFUN_CMD_ELEMENT(funcname, cmdname, cmdstr, helpstr, attrs, dnum)     \
	static struct cmd_element cmdname = {                                  \
		.string = cmdstr,                                              \
		.func = funcname,                                              \
		.doc = helpstr,                                                \
		.attr = attrs,                                                 \
		.daemon = dnum,                                                \
		.name = #cmdname,                                              \
	};

DEFUN

#define DEFUN(funcname, cmdname, cmdstr, helpstr)                              \
	DEFUN_CMD_FUNC_DECL(funcname)                                          \
	DEFUN_CMD_ELEMENT(funcname, cmdname, cmdstr, helpstr, 0, 0)            \
	DEFUN_CMD_FUNC_TEXT(funcname)

funcname 声明

#define DEFUN_CMD_FUNC_DECL(funcname)                                          \
	static int funcname(const struct cmd_element *, struct vty *, int,     \
			    struct cmd_token *[]);

cmdname 结构体定义、初始化

/* helper defines for end-user DEFUN* macros */
#define DEFUN_CMD_ELEMENT(funcname, cmdname, cmdstr, helpstr, attrs, dnum)     \
	static struct cmd_element cmdname = {                                  \
		.string = cmdstr,                                              \
		.func = funcname,                                              \
		.doc = helpstr,                                                \
		.attr = attrs,                                                 \
		.daemon = dnum,                                                \
		.name = #cmdname,                                              \
	};

#define DEFUN_CMD_FUNC_TEXT(funcname)                                          \
	static int funcname(const struct cmd_element *self                     \
			    __attribute__((unused)),                           \
			    struct vty *vty __attribute__((unused)),           \
			    int argc __attribute__((unused)),                  \
			    struct cmd_token *argv[] __attribute__((unused)))

对比

DEFUN和DEFPY区别

DEFUN 和 DEFPY 都可以定义命令。DEFPY(...) 是 DEFUN() 的增强版，由python/clidef.py进行预处理。python脚本解析命令定义字符串，提取变量名称和类型，并生成一个C语言包装函数，解析变量并传递给它们。这意味着在CLI函数体中，你将收到具有适当类型的额外参数。

参考资料：
FRRouting Developer’s Guide