Question

Download everything.c. You can compile and run it with the usual commands.

You know that putting all your code into a single file is bad form. Therefore, your goal is to refactor everything.c so that the code is in multiple source (.c and .h) files, as well as write a Makefile to compile and run the program. Here are your constraints:

• There should be no code duplication
• Each .c and .h file must only #include header files that it actually needs to
• Stack and Queue need to be in their own source file
• The main function should be in its own source file
• The Makefile must have at least the following targets (of course you need more)
  • runOn4: run the application on the command line argument 4
  • runOn20: run the application on the command line argument 20
  • clean: remove all generated files, leaving only the source files and the Makefile
  • symbols: print the symbols of all .o files and .exe file
  • assemblies: creates one .s file for each .c file

everything.c code:

#include <stdio.h>
#include <stdlib.h>

#define SHOULD_PRINT 1

struct Node {
int data;
struct Node *next;
};

struct Stack {
struct Node *head;
};

struct Queue {
struct Node *head;
struct Node *tail;
};

struct Node* new_node(int d) {
struct Node *n = malloc(1 * sizeof(struct Node));
n->data = d;
n->next = NULL;
return n;
}

void push(struct Stack *s, int e) {
struct Node* newFirst = new_node(e);
newFirst->next = s->head;
s->head = newFirst;
}

int pop(struct Stack *s) {
int result = s->head->data;
s->head = s->head->next;
return result;
}

void enqueue(struct Queue *q, int e) {
struct Node* newFirst = new_node(e);
if (q->head == NULL) {
q->head = newFirst;
q->tail = newFirst;
} else {
q->tail->next = newFirst;
q->tail = newFirst;
}
}

int dequeue(struct Queue *q) {
int result = q->head->data;
q->head = q->head->next;
if (q->head == NULL) {
q->tail = NULL;
}
return result;
}
  
int main(int argc, char **argv) {
if (argc < 2) {
printf("requires one argument\n");
exit(1);
}
int n = atoi(argv[1]);
struct Stack *s = malloc(sizeof(struct Stack));
struct Queue *q = malloc(sizeof(struct Queue));
for (int i=0; i<n; i++) {
if (SHOULD_PRINT) printf("put %d on the stack\n", i);
push(s, i);
}
for (int i=0; i<n; i++) {
enqueue(q, pop(s));
}
for (int i=0; i<n; i++) {
if (SHOULD_PRINT) printf("get %d off of the queue\n", dequeue(q));
}
}

Answer 1

Here is the above program splitted in multiple files

Main.c

#include<stdio.h>
#include<stdlib.h>
#include"Node.c"

int main(int argc, char **argv) {
if (argc < 2) {
printf("requires one argument\n");
exit(1);
}
int n = atoi(argv[1]);
struct Stack *s = malloc(sizeof(struct Stack));
struct Queue *q = malloc(sizeof(struct Queue));
int i;
for (i=0; i<n; i++) {
if (SHOULD_PRINT) printf("put %d on the stack\n", i);
push(s, i);
}
for (i=0; i<n; i++) {
enqueue(q, pop(s));
}
for (i=0; i<n; i++) {
if (SHOULD_PRINT) printf("get %d off of the queue\n", dequeue(q));
}
}

Node.h

#include <stdio.h>
#include <stdlib.h>
#define SHOULD_PRINT 1

struct Node {
int data;
struct Node *next;
};

struct Stack {
struct Node *head;
};

struct Queue {
struct Node *head;
struct Node *tail;
};

Node.c

#include <stdio.h>
#include <stdlib.h>
#include "Node.h"
#define SHOULD_PRINT 1

struct Node* new_node(int d) {
struct Node *n = malloc(1 * sizeof(struct Node));
n->data = d;
n->next = NULL;
return n;
}

void push(struct Stack *s, int e) {
struct Node* newFirst = new_node(e);
newFirst->next = s->head;
s->head = newFirst;
}

int pop(struct Stack *s) {
int result = s->head->data;
s->head = s->head->next;
return result;
}

void enqueue(struct Queue *q, int e) {
struct Node* newFirst = new_node(e);
if (q->head == NULL) {
q->head = newFirst;
q->tail = newFirst;
} else {
q->tail->next = newFirst;
q->tail = newFirst;
}
}

int dequeue(struct Queue *q) {
int result = q->head->data;
q->head = q->head->next;
if (q->head == NULL) {
q->tail = NULL;
}
return result;
}