I tried to implement a generic stack in C using void pointers and tried to keep it as simple as possible by delegating all responsibility to the caller of the functions and avoiding more sophisticated approaches. Here are the three files:

stack.h

stack.c

stackclient.c

I tried to implement a generic stack in C using void pointers and tried to keep it as simple as possible by delegating all responsibility to the caller of the functions and avoiding more sophisticated approaches.

stack.h

stack.c

stackclient.c

I tried to implement a generic stack in C using void pointers and tried to keep it as simple as possible by delegating all responsibility to the caller of the functions and avoiding more sophisticated approaches. Here are the three files:

stack.h

#ifndef STACK_H
#define STACK_H

#include <stdbool.h>

struct Stack {
    void *data;
    struct Stack *next;
};

/*
 * We declare a pointer to a Stack structure thereby making use of incomplete
 * types. Clients that pull in stack.h will be able to declare variables of type
 * pstack which are pointers to pointers to Stack structures.
 * */
typedef struct Stack *pstack;

bool is_empty(pstack *s);
void make_empty(pstack *s);
void push(struct Stack **s, void *new_num);
void *pop(pstack *s);

#endif /* STACK_H */

stack.c

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

bool is_empty(pstack *s) { return !s; }

void make_empty(pstack *s)
{
    if (!is_empty(s))
        pop(s);
}

void *pop(pstack *s)
{
    struct Stack *tmp;
    void *i;

    if (is_empty(s))
        exit(EXIT_FAILURE);

    tmp = *s;
    i = (*s)->data;
    *s = (*s)->next;
    free(tmp);
    return i;
}

void push(struct Stack **s, void *new_num)
{
    struct Stack *new_node = malloc(sizeof(struct Stack));
    if (!new_node)
        exit(EXIT_FAILURE);

    new_node->data = new_num;
    new_node->next = *s;
    *s = new_node;
}

stackclientc

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

int main(void)
{
    pstack s1;
    void *n;
    int i = 1;
    int j = 2;

    push(&s1, &i);
    push(&s1, &j);

    n = pop(&s1);
    printf("Popped %d from s1\n", *((int *)n));
    n = pop(&s1);
    printf("Popped %d from s1\n", *((int *)n));

    exit(EXIT_SUCCESS);
}

I tried to implement a generic stack in C using void pointers and tried to keep it as simple as possible by delegating all responsibility to the caller of the functions and avoiding more sophisticated approaches. Here are the three files:

stack.h

#ifndef STACK_H
#define STACK_H

#include <stdbool.h>

struct Stack {
    void *data;
    struct Stack *next;
};

/*
 * We declare a pointer to a Stack structure thereby making use of incomplete
 * types. Clients that pull in stack.h will be able to declare variables of type
 * pstack which are pointers to pointers to Stack structures.
 * */
typedef struct Stack *pstack;

bool is_empty(pstack *s);
void make_empty(pstack *s);
void push(struct Stack **s, void *new_num);
void *pop(pstack *s);

#endif /* STACK_H */

stack.c

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

bool is_empty(pstack *s) { return !s; }

void make_empty(pstack *s)
{
    if (!is_empty(s))
        pop(s);
}

void *pop(pstack *s)
{
    struct Stack *tmp;
    void *i;

    if (is_empty(s))
        exit(EXIT_FAILURE);

    tmp = *s;
    i = (*s)->data;
    *s = (*s)->next;
    free(tmp);
    return i;
}

void push(struct Stack **s, void *new_num)
{
    struct Stack *new_node = malloc(sizeof(struct Stack));
    if (!new_node)
        exit(EXIT_FAILURE);

    new_node->data = new_num;
    new_node->next = *s;
    *s = new_node;
}

stackclient.c

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

int main(void)
{
    pstack s1;
    void *n;
    int i = 1;
    int j = 2;

    push(&s1, &i);
    push(&s1, &j);

    n = pop(&s1);
    printf("Popped %d from s1\n", *((int *)n));
    n = pop(&s1);
    printf("Popped %d from s1\n", *((int *)n));

    exit(EXIT_SUCCESS);
}