Question

我实现了一个树，其节点看起来像这样：

typedef struct node_s {
   struct node_s *parent;
   struct node_s *left;
   struct node_s *right;
   data_t *data;
}node_t;

其中*data指向带有key的数据结构，该数据结构用于对树进行排序。

当我添加一个新节点时，它看起来像这样：

node_t *add_Item (node_t *root){  //root is the root of the tree 

    ...

    data_t *new_data;
    new_data = calloc(1,sizeof(data_t));
    if(!new_data){
        ...    //Error handling
    }
    root = insert_Node(root, new_data);
    ... //modifying new_data

    return root;
}

node_t insert_Node(node_t *root, data_t *data){

    ...    \\tree traversing and searching

    if(root->data->key == data->key){   \\if the key is already in the tree it should be replaced
        data_t *temp_data = root->data;
        root->data = data;
        free(temp_data);  \\freeing the old data
    }

    ...

    return root;
}

我不了解 free(temp_data) 不起作用。另外，调试信息对我来说没有意义：

temp_data = 0x0000024C856DA950
root->data = 0x0000024C856DA9D0
和调试消息：HEAP[Program.exe]: Invalid address specified to RtlValidateHeap( 0000024C856D0000, 0000024C856DA920 ) 错误消息中的地址总是0x30小于temp_data。

只要能帮助任何人：Windows 10，Visual Studio

编辑-最小的可复制示例

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

typedef struct data_s {
    long key;
}data_t;

typedef struct node_s {
    struct node_s* parent;
    struct node_s* left;
    struct node_s* right;
    data_t* data;
}node_t;


node_t* init_node(data_t* data) {
    node_t* new_node;
    if ((new_node = calloc(1, sizeof(node_t)))) {
        new_node->data = data;
        fprintf(stderr, "node created\n");
    }
    return new_node;
}

node_t* insert_node(node_t* root, data_t* data) {

    node_t* node;

    if (root) {
        if (root->data->key == data->key) {
            printf("This item alreay exists!\n%ld will be replaced!\n", data->key);
            data_t* temp_data;
            temp_data = root->data;
            root->data = data;
            free(temp_data);

        }
        else if (root->data->key > data->key) {
            node = insert_node(root->right, data);
            root->right = node;
            node->parent = root;
        }
        else {
            node = insert_node(root->left, data);
            root->left = node;
            node->parent = root;
        }

    }
    else {
        root = init_node(data);
    }
    return root;
}


int main(int argc, char** argv) {

    data_t* data;
    node_t* root = 0;

    while (1) {

        if (!(data = calloc(1, sizeof(data_t)))) {
            return(EXIT_FAILURE);
        }
        printf("What is the key for the new data?\n");
        scanf("%ld", &(data->key));
        root = insert_node(root, data);

        //there would be more editing of data afterwards
    }

    return(EXIT_SUCCESS);
}

这似乎可行，但我不知道为什么可行，而我的其他程序却无效。

free（data）尝试释放错误的地址

0 个答案: