C delete函数中的循环双向链表

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

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

void delete(Node** head, int value) {
    if (*head == NULL) {
        printf("链表为空，无法删除节点。\n");
        return;
    }

    Node* current = *head;
    Node* prev = NULL;

    // 寻找待删除节点
    while (current->data != value) {
        if (current->next == *head) {
            printf("未找到值为%d的节点。\n", value);
            return;
        }

        prev = current;
        current = current->next;
    }

    // 如果待删除节点是唯一节点
    if (current->next == *head && prev == NULL) {
        *head = NULL;
        free(current);
        return;
    }

    // 如果待删除节点是头节点
    if (current == *head) {
        prev = *head;
        while (prev->next != *head)
            prev = prev->next;
        *head = (*head)->next;
        prev->next = *head;
        (*head)->prev = prev;
        free(current);
    }

    // 如果待删除节点是尾节点
    else if (current->next == *head) {
        prev->next = *head;
        (*head)->prev = prev;
        free(current);
    }

    // 如果待删除节点是中间节点
    else {
        Node* temp = current->next;
        prev->next = temp;
        temp->prev = prev;
        free(current);
    }
}

int main() {
    Node* head = NULL;
    Node* node1 = (Node*)malloc(sizeof(Node));
    Node* node2 = (Node*)malloc(sizeof(Node));
    Node* node3 = (Node*)malloc(sizeof(Node));

    node1->data = 1;
    node2->data = 2;
    node3->data = 3;

    head = node1;
    node1->prev = node3;
    node1->next = node2;
    node2->prev = node1;
    node2->next = node3;
    node3->prev = node2;
    node3->next = node1;

    printf("删除前的链表：\n");
    Node* current = head;
    do {
        printf("%d ", current->data);
        current = current->next;
    } while (current != head);
    printf("\n");

    delete(&head, 2);

    printf("删除后的链表：\n");
    current = head;
    do {
        printf("%d ", current->data);
        current = current->next;
    } while (current != head);
    printf("\n");

    return 0;
}