A python script to extract the events from SI Labs native_gecko.h into an event loop handler that calls weak functions, allowing you to define event handler functions with parameters instead of a big switch statement with an event data struct.

create_native_gecko.py

#!/usr/bin/env python

import re

native_gecko_file = open("/Applications/Simplicity Studio.app/Contents/Eclipse/developer/sdks/gecko_sdk_suite/v2.2/protocol/bluetooth/ble_stack/inc/soc/native_gecko.h", "r")
contents = native_gecko_file.read()
native_gecko_file.close()

pattern = re.compile(r'gecko_evt_(.*?)_id\s')

c_string = ""
h_string = ""

for (event) in re.findall(pattern, contents):
	c_string += r"""
		case gecko_evt_{0}_id: {{""".format(event)
	h_string += r"""
__attribute__ ((weak)) void gecko_evt_{0}(""".format(event)
	event_params_pattern = re.compile(r'gecko_msg_%s_evt_t\n\{\n(.*?)\n\}\);' % event, re.MULTILINE | re.DOTALL)
	match = re.search(event_params_pattern, contents)
	if match:
		c_string += r"""
			struct gecko_msg_{0}_evt_t* data = &evt->data.evt_{0};
			gecko_evt_{0}(""".format(event)
		event_param_pattern = re.compile(r'\s+(.*?)\s+(.*?);')
		for (typename, param) in re.findall(event_param_pattern, match.group(1)):
			c_string += "data->%s, " % param
			h_string += "{0} {1}, ".format(typename, param)
		c_string = c_string[:-2]
		h_string = h_string[:-2]
	else:
		c_string += r"""
			gecko_evt_{0}(""".format(event)
		h_string += "void"
	
	c_string += r""");
		} break;"""
	h_string += ");"

gecko_weak_c_file = open("gecko_weak.c", "w+")
gecko_weak_c_file.write(r"""/*****************************************************************************
 * @file gecko_weak.c
 * @brief Gecko weak event functions
 * @author Nick Brook
 * @version 1.00
 ******************************************************************************
 * @section License
 * <b>(C) Copyright 2017 Nick Brook, https://www.nickbrook.me</b>
 *******************************************************************************
 *
 * Permission is granted to anyone to use this software for any purpose,
 * including commercial applications, and to alter it and redistribute it
 * freely, subject to the following restrictions:
 *
 * 1. The origin of this software must not be misrepresented; you must not
 *    claim that you wrote the original software.
 * 2. Altered source versions must be plainly marked as such, and must not be
 *    misrepresented as being the original software.
 * 3. This notice may not be removed or altered from any source distribution.
 *
 * DISCLAIMER OF WARRANTY/LIMITATION OF REMEDIES: Nick Brook has no
 * obligation to support this Software. Nick Brook is providing the
 * Software "AS IS", with no express or implied warranties of any kind,
 * including, but not limited to, any implied warranties of merchantability
 * or fitness for any particular purpose or warranties against infringement
 * of any proprietary rights of a third party.
 *
 * Nick Brook will not be liable for any consequential, incidental, or
 * special damages, or any other relief, or for any claim by any third party,
 * arising from your use of this Software.
 *
 ******************************************************************************/

#include "gecko_weak.h"
#include "gecko_weak_handler.h"
#include "native_gecko.h"

void gecko_evt_handle(struct gecko_cmd_packet* evt) {{
	switch (BGLIB_MSG_ID(evt->header)) {{{0}
	}}
}}

void gecko_evt_loop() {{
	while (1) {{
		/* Event pointer for handling events */
		struct gecko_cmd_packet* evt;

		/* Check for stack event. */
		evt = gecko_wait_event();

		gecko_evt_handle(evt);
	}}
}}

""".format(c_string))
gecko_weak_c_file.close()

gecko_weak_h_file = open("gecko_weak.h", "w+")
gecko_weak_h_file.write(r"""/*****************************************************************************
 * @file gecko_weak.h
 * @brief Gecko weak event functions
 * @author Nick Brook
 * @version 1.00
 ******************************************************************************
 * @section License
 * <b>(C) Copyright 2017 Nick Brook, https://www.nickbrook.me</b>
 *******************************************************************************
 *
 * Permission is granted to anyone to use this software for any purpose,
 * including commercial applications, and to alter it and redistribute it
 * freely, subject to the following restrictions:
 *
 * 1. The origin of this software must not be misrepresented; you must not
 *    claim that you wrote the original software.
 * 2. Altered source versions must be plainly marked as such, and must not be
 *    misrepresented as being the original software.
 * 3. This notice may not be removed or altered from any source distribution.
 *
 * DISCLAIMER OF WARRANTY/LIMITATION OF REMEDIES: Nick Brook has no
 * obligation to support this Software. Nick Brook is providing the
 * Software "AS IS", with no express or implied warranties of any kind,
 * including, but not limited to, any implied warranties of merchantability
 * or fitness for any particular purpose or warranties against infringement
 * of any proprietary rights of a third party.
 *
 * Nick Brook will not be liable for any consequential, incidental, or
 * special damages, or any other relief, or for any claim by any third party,
 * arising from your use of this Software.
 *
 ******************************************************************************/

#ifndef GECKO_WEAK_H_
#define GECKO_WEAK_H_

#include "native_gecko.h"
{0}

#endif /* GECKO_WEAK_H_ */
""".format(h_string))
gecko_weak_h_file.close()

gecko_weak_handler.h

/*****************************************************************************
 * @file gecko_weak_handler.h
 * @brief Gecko weak event handlers
 * @author Nick Brook
 * @version 1.00
 ******************************************************************************
 * @section License
 * <b>(C) Copyright 2017 Nick Brook, https://www.nickbrook.me</b>
 *******************************************************************************
 *
 * Permission is granted to anyone to use this software for any purpose,
 * including commercial applications, and to alter it and redistribute it
 * freely, subject to the following restrictions:
 *
 * 1. The origin of this software must not be misrepresented; you must not
 *    claim that you wrote the original software.
 * 2. Altered source versions must be plainly marked as such, and must not be
 *    misrepresented as being the original software.
 * 3. This notice may not be removed or altered from any source distribution.
 *
 * DISCLAIMER OF WARRANTY/LIMITATION OF REMEDIES: Nick Brook has no
 * obligation to support this Software. Nick Brook is providing the
 * Software "AS IS", with no express or implied warranties of any kind,
 * including, but not limited to, any implied warranties of merchantability
 * or fitness for any particular purpose or warranties against infringement
 * of any proprietary rights of a third party.
 *
 * Nick Brook will not be liable for any consequential, incidental, or
 * special damages, or any other relief, or for any claim by any third party,
 * arising from your use of this Software.
 *
 ******************************************************************************/

#ifndef GECKO_WEAK_HANDLER_H_
#define GECKO_WEAK_HANDLER_H_

#include "native_gecko.h"
#include "gecko_weak.h"

void gecko_evt_handle(struct gecko_cmd_packet* evt);

void gecko_evt_loop();

#endif /* GECKO_WEAK_HANDLER_H_ */