c - While 循环在条件出现之前停止

Question

我的代码有问题。我想加载一本适用于小字典的字典。但是当我尝试加载更大的版本时，我的 while 循环停在第 701 个单词“acclimatization”处，然后程序继续。我在论坛上搜索了很多并尝试了很多东西，但我就是找不到造成这种情况的原因。有谁知道这是如何发生的吗？

字典.c

bool load(const char* dictionary)
{
// reserve space for word
char* word = malloc(sizeof(char*));

// open file
FILE* dict = fopen(dictionary, "r");

if (dict == NULL)
{
    fclose(dict);
    fprintf(dict, "Could not load %s.\n", dictionary);
    return 1;
}

root = (struct node *) malloc(sizeof(struct node));
root->is_word = false;

//Loops over word aslong the EOF is not reached
while (fgets(word,LENGTH,dict) != NULL)
{
        printf("word = %s\n", word);
        int word_length = strlen(word) -1;
        node* current = root;
        word_count++;
        //Loops over letters
        for (int i = 0; i < word_length; i++)
        {
            int index;
            node *next_node;
            // checks if letter isnt a apostrophe
            if(word[i] == 39)
            {
                index = MAX_CHARS - 1;
            }
            // gets nummeric value of letter
            else
            {
                index = tolower(word[i]) - 'a';
            }


            next_node = current->children[index];

            // creates new node if letter didnt exists before
            if(next_node == NULL)
            {
                next_node = malloc(sizeof(node));
                current->children[index] = next_node;
                current->is_word = false;
                printf("new letter: %c\n", word[i]);
            }
            else
            {
                printf("letter: %c\n", word[i]);
            }
            // checks for end of the word
            if(i == word_length - 1)
            {
                next_node->is_word = true;
            }
            current = next_node;
        }   
}
return true;
}

节点定义为:

// node

typedef struct node
{
    bool is_word;
    struct node* children[27];
}
node;

Answer 1

char* word = malloc(sizeof(char*));

根据平台的不同，它可以是 4 或 8 。您需要分配更多内存。

char* word;
word = malloc(LENGTH);    // LENGTH as you use it here while (fgets(word,LENGTH,dict) != NULL)
if(word!=NULL){            // and checking if malloc is successful

   // your code 
    free(word);               // freeing allocated memory
    return true;
 }
else {                   // executed only if malloc fails
        //handle error
  }

您可以提供任何所需的尺寸。

注意 - 使用函数 free() ，每次分配内存时都需要释放。