如何在C中正确分配结构数组哈希图中的项目 [英] How to properly malloc item in struct array hashmap in C
问题描述
在以下代码中,我正在使用malloc将新项目添加到哈希图中.我以为我已经检查了所有使用malloc的框,但是valgrind说我的内存泄漏.有人可以指出我出了问题的地方吗?
In the following code, I'm using malloc for adding a new item to a hashmap. I thought I've checked all the boxes for properly using malloc, but valgrind says I've got a memory leak on them. Can someone point me to where I've gone wrong?
#include <stdlib.h>
#include <string.h>
typedef struct node
{
char content[46];
struct node* next;
}
node;
typedef node* hashmap_t;
int main (int argc, char *argv[]) {
hashmap_t hashtable[1000];
node *n = malloc(sizeof(node));
if(n == NULL) return 0;
hashmap_t new_node = n;
new_node->next = malloc(sizeof(node));
if(new_node->next == NULL) {
free(n);
return 0;
}
strncpy(new_node->content, "hello", 45);
hashtable[10] = new_node;
for(int y=0; y < 1000; y++) {
if(hashtable[y] != NULL) {
free(hashtable[y]->next);
free(hashtable[y]);
}
}
return 1;
}
推荐答案
在线
if(hashtable[y] != NULL)
请勿将hashtable
初始化为任何值,并且还将其声明为局部变量.初始值应为某个垃圾值.因此,您不能假设数组的所有1000个元素的hashtable[y]
均应为NULL
.
You do not initialise hashtable
to any value and it is also declared as a local variable. The initial value shall be some garbage value. So you cannot assume that if hashtable[y]
shall be NULL
for all 1000 elements of the array.
您可以在声明例如
hashmap_t hashtable[1000] = {0};
,或者您可以将其声明为全局变量.
or you can declare it as a global variable.
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