samples, tests: Switch main return type from void to int

This applies the coccinelle script to another set of files:

   samples/bluetooth/bthome_sensor_template/src/main.c
   samples/boards/stm32/power_mgmt/standby_shutdown/src/main.c
   samples/drivers/smbus/src/main.c
   samples/drivers/virtualization/ivshmem/doorbell/src/ivshmem.c
   samples/fuel_gauge/max17048/src/main.c
   samples/hello_world/src/main.c
   samples/sensor/proximity_polling/src/main.c
   samples/subsys/logging/ble_backend/src/main.c
   tests/drivers/build_all/mfd/src/main.c

Signed-off-by: Keith Packard <keithp@keithp.com>

samples/bluetooth/bthome_sensor_template/src/main.c

@@ -51,7 +51,7 @@ static void bt_ready(int err)
 	}
 }
 
-void main(void)
+int main(void)
 {
 	int err;
 	int temp = 0;
@@ -62,7 +62,7 @@ void main(void)
 	err = bt_enable(bt_ready);
 	if (err) {
 		printk("Bluetooth init failed (err %d)\n", err);
-		return;
+		return 0;
 	}
 
 	for (;;) {
@@ -78,4 +78,5 @@ void main(void)
 		}
 		k_sleep(K_MSEC(BT_GAP_ADV_SLOW_INT_MIN));
 	}
+	return 0;
 }

samples/boards/stm32/power_mgmt/standby_shutdown/src/main.c

@@ -88,7 +88,7 @@ void thread_shutdown_standby_mode(void)
 K_THREAD_DEFINE(thread_shutdown_standby_mode_id, STACKSIZE, thread_shutdown_standby_mode,
 	NULL, NULL, NULL, PRIORITY, 0, 0);
 
-void main(void)
+int main(void)
 {
 	int ret;
 	uint32_t cause;
@@ -117,14 +117,14 @@ void main(void)
 	if (!gpio_is_ready_dt(&button)) {
 		printk("Error: button device %s is not ready\n",
 			button.port->name);
-		return;
+		return 0;
 	}
 
 	ret = gpio_pin_configure_dt(&button, GPIO_INPUT);
 	if (ret != 0) {
 		printk("Error %d: failed to configure %s pin %d\n",
 			ret, button.port->name, button.pin);
-		return;
+		return 0;
 	}
 
 	ret = gpio_pin_interrupt_configure_dt(&button,
@@ -132,7 +132,7 @@ void main(void)
 	if (ret != 0) {
 		printk("Error %d: failed to configure interrupt on %s pin %d\n",
 			ret, button.port->name, button.pin);
-		return;
+		return 0;
 	}
 
 	gpio_init_callback(&button_cb_data, button_pressed, BIT(button.pin));
@@ -152,4 +152,5 @@ void main(void)
 		led_is_on = !led_is_on;
 	}
 
+	return 0;
 }

samples/drivers/smbus/src/main.c

@@ -6,7 +6,8 @@
 
 #include <zephyr/kernel.h>
 
-void main(void)
+int main(void)
 {
 	printk("Start SMBUS shell sample %s\n", CONFIG_BOARD);
+	return 0;
 }

samples/drivers/virtualization/ivshmem/doorbell/src/ivshmem.c

@@ -266,7 +266,7 @@ static void ivshmem_sample_userspace_doorbell(void)
 }
 #endif /* CONFIG_USERSPACE */
 
-void main(void)
+int main(void)
 {
 #ifdef CONFIG_USERSPACE
 	ivshmem_sample_userspace_doorbell();
@@ -275,4 +275,5 @@ void main(void)
 #endif
 	/* if the code reaches here, it means the setup/loop has failed */
 	ivshmem_sample_failed();
+	return 0;
 }

samples/fuel_gauge/max17048/src/main.c

@@ -11,21 +11,21 @@
 
 
 
-void main(void)
+int main(void)
 {
 	const struct device *const dev = DEVICE_DT_GET_ANY(maxim_max17048);
 	int ret = 0;
 
 	if (dev == NULL) {
 		printk("\nError: no device found.\n");
-		return;
+		return 0;
 	}
 
 	if (!device_is_ready(dev)) {
 		printk("\nError: Device \"%s\" is not ready; "
 		       "check the driver initialization logs for errors.\n",
 		       dev->name);
-		return;
+		return 0;
 	}
 
 
@@ -33,7 +33,7 @@ void main(void)
 	printk("Found device \"%s\", getting fuel gauge data\n", dev->name);
 
 	if (dev == NULL) {
-		return;
+		return 0;
 	}
 
 	while (1) {
@@ -101,4 +101,5 @@ void main(void)
 
 		k_sleep(K_MSEC(5000));
 	}
+	return 0;
 }

samples/hello_world/src/main.c

@@ -6,8 +6,8 @@
 
 #include <zephyr/kernel.h>
 
-void main(void)
+int main(void)
 {
 	printk("Hello World! %s\n", CONFIG_BOARD);
-	return;
+	return 0;
 }

samples/sensor/proximity_polling/src/main.c

@@ -38,7 +38,7 @@ void print_prox_data(void)
 	}
 }
 
-void main(void)
+int main(void)
 {
 	printk("Proximity sensor sample application\n");
 	printk("Found %d proximity sensor(s): ", ARRAY_SIZE(prox_devices));
@@ -51,4 +51,5 @@ void main(void)
 		k_sleep(K_MSEC(2000));
 		print_prox_data();
 	}
+	return 0;
 }

samples/subsys/logging/ble_backend/src/main.c

@@ -75,7 +75,7 @@ void backend_ble_hook(bool status, void *ctx)
 }
 
 
-void main(void)
+int main(void)
 {
 	int err;
 
@@ -84,7 +84,7 @@ void main(void)
 	err = bt_enable(NULL);
 	if (err) {
 		LOG_ERR("Bluetooth init failed (err %d)", err);
-		return;
+		return 0;
 	}
 
 	bt_conn_auth_cb_register(&auth_cb_display);
@@ -97,4 +97,5 @@ void main(void)
 		LOG_INF("Uptime %d secs", uptime_secs);
 		k_sleep(K_MSEC(1000));
 	}
+	return 0;
 }

tests/drivers/build_all/mfd/src/main.c

@@ -4,6 +4,7 @@
  * SPDX-License-Identifier: Apache-2.0
  */
 
-void main(void)
+int main(void)
 {
+	return 0;
 }