Refactor C sample (#47)

* Add fomatter settings for .c file

* Add fomatter settings for .c file

* Refactor .c sample

* Refactor .c sample

* Fix merge

* Revert "Fix merge"

This reverts commit c7596bb.

Author: Tiryoh

SampleProgram/step1.c

@@ -1,6 +1,7 @@
-#include "fcntl.h"
+#include <fcntl.h>
+#include <unistd.h>
 
-void main(void) {
+int main(void) {
     int led[4];
     int i;
 
@@ -22,4 +23,5 @@ void main(void) {
     for (i = 0; i < 4; i++) {
         close(led[i]);
     }
+    return 0;
 }

SampleProgram/step2.c

@@ -1,4 +1,7 @@
-#include "fcntl.h"
+#include <fcntl.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <unistd.h>
 
 int _Getch(void) {
     int ch;
@@ -8,7 +11,7 @@ int _Getch(void) {
     return ch;
 }
 
-void main(void) {
+int main(void) {
     int buzzer = open("/dev/rtbuzzer0", O_WRONLY);
     int c = 1;
 
@@ -63,4 +66,5 @@ void main(void) {
         }
     }
     close(buzzer);
+    return 0;
 }

SampleProgram/step3.c

@@ -1,4 +1,5 @@
-#include "fcntl.h"
+#include <fcntl.h>
+#include <unistd.h>
 
 char get_SW0(void) {
     char buf[2];
@@ -27,7 +28,7 @@ char get_SW2(void) {
     return buf[0];
 }
 
-void main(void) {
+int main(void) {
     int state0, state1, state2;
     int LED0, LED1, LED2, LED3;
 
@@ -78,4 +79,5 @@ void main(void) {
             }
         }
     }
+    return 0;
 }

SampleProgram/step4.c

@@ -2,7 +2,7 @@
 #include <stdio.h>
 #include <unistd.h>
 
-void main(void) {
+int main(void) {
     int motoren = open("/dev/rtmotoren0", O_WRONLY);
     int motor_l = open("/dev/rtmotor_raw_l0", O_WRONLY);
     int motor_r = open("/dev/rtmotor_raw_r0", O_WRONLY);
@@ -44,4 +44,5 @@ void main(void) {
     close(motor_l);
     close(motor_r);
     close(motor);
+    return 0;
 }

SampleProgram/step5.c

@@ -2,7 +2,7 @@
 #include <stdio.h>
 #include <unistd.h>
 
-void main(void) {
+int main(void) {
     int buff_size = 256;
     FILE *fp;
 
@@ -16,4 +16,5 @@ void main(void) {
         fclose(fp);
         usleep(500 * 1000);
     }
+    return 0;
 }