darray

/* darray.c - dynamic array
 *
 * 2014, gmb */

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


int *darr;
unsigned int size = 0;

int darr_init(int *darr){

    *darr = (int *) malloc(sizeof(int));

    if(darr == NULL)
        return -1;
    else
        return 0;
}

void darr_del(int *darr){
    free(darr);
}

int darr_add(int *darr, int element){
    unsigned int i;

    int *tmp = (int *) malloc(sizeof(int) * size);

    if(tmp == NULL)
        return -1;

    for(i = 0; i < size; i++){
        *(tmp + i) = *(darr + i);
    }

    free(darr);
    *darr = (int *) malloc(sizeof(int) * (size + 1));

    if(darr == NULL)
        return -2;

    for(i = 0; i < size; i++){
        *(darr + i) = *(tmp + i);
    }

    *(darr + size) = element;
    size++;

    free(tmp);

    return 0;
}

int darr_get(int *darr, unsigned int i){
    return *(darr + i);
}

int darr_rem(int *darr, unsigned int i){
    unsigned int j, k = 0;

    if(i >= size)
        return -1;

    int *tmp = (int *) malloc(sizeof(int) * (size - 1));

    if(tmp == NULL)
        return -1;

    for(j = 0; j < size; j++){
        if(j != i){
            *(tmp + k) = *(darr + j);
            k++;
        }
    }

    free(darr);
    *darr = (int *) malloc(sizeof(int) * (size - 1));

    if(darr == NULL)
        return -2;

    for(j = 0; j < (size - 1); j++){
        *(darr + j) = *(tmp + j);
    }

    size--;

    free(tmp);

    return 0;
}

void darr_print(int *darr){

    unsigned int i;

    for(i = 0; i < size; i++){
        printf("%d ", *(darr + i));
    }
}

int main(){

    int err = 0;
    unsigned int i = 0;

    if((err = darr_init(&darr)) < 0){
        fprintf(stderr, "darr_init() failed");
        exit(1);
    }

    if((err = darr_add(&darr, 1)) < 0){
        fprintf(stderr, "darr_add() failed");
        exit(2);
    }

     if((err = darr_add(&darr, 2)) < 0){
        fprintf(stderr, "darr_add() failed");
        exit(2);
    }

    printf("darray: ");

    darr_print(&darr);

    printf("\n");

    if((err = darr_add(&darr, 3)) < 0){
        fprintf(stderr, "darr_add() failed");
        exit(2);
    }

    printf("after add: ");

    for(i = 0; i < size; i++){
        printf("%d ", darr_get(&darr, i));
    }

    printf("\n");

    if((err = darr_rem(&darr, 1)) < 0){
        fprintf(stderr, "darr_rem() failed");
        exit(3);
    }

    printf("after remove: ");
    darr_print(&darr);

    darr_del(&darr);

    return 0;
}