dll delete sda

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

typedef struct Node {
    int data;
    struct Node *prev, *nxt;
} Node;

Node *newNode(int data, Node *prev, Node *nxt) {
    Node* node = (Node*)malloc(sizeof(Node));
    if (node == NULL) {
        perror("");
        exit(1);
    }
    node->data = data;
    node->prev = prev;
    node->nxt = nxt;
    return node;
}

void addToStart(Node **head, int data) {
    Node* node = newNode(data, NULL, *head);
    if ((*head) != NULL) {
        (*head)->prev = node;
    }
    (*head) = node;
}

void printList(const Node *const head) {
    for (Node* tmp = head; tmp != NULL; tmp = tmp->nxt) {
        printf("%d ", tmp->data);
    }
    putchar('\n');
}

Node* searchNode(const Node *const head, int data) {
    for (Node* tmp = head; tmp != NULL; tmp = tmp->nxt) {
        if (tmp->data == data) {
            return tmp;
        }
    }
    return NULL;
}

void deleteNode(Node **head, Node *target) {
    if (target == *head) {
        *head = target->nxt;
        return;
    }
    target->prev->nxt = target->nxt;
    if (target->nxt == NULL) {
        return;
    }
    target->nxt->prev = target->prev;
}

void deleteByValue(Node **head, int data) {
    Node* target = searchNode(*head, data);
    if (target != NULL) {
        deleteNode(head, target);
    }
}

int main(void) {
    Node* node = NULL;
    addToStart(&node, 3);
    addToStart(&node, 2);
    addToStart(&node, 1);
    deleteByValue(&node, 2);
    addToStart(&node, 12);
    printList(node);
    return 0;
}