Load giving segmentation fault

Question

I have implemented this for load. But if I execute the speller file in terminal, I get segmentation fault. I haven't implemented anything except for load as of now.

here it is:

 //Trie Data Structure.
typedef struct node
{
    bool isWord;
    struct node* children[27];
}node;

//Make a new node function prototype.
node* newNode();

//Declaring it here so that the root is global. and all other global variables
char word[45+1];
node* root = NULL;
int length;
int c;
unsigned int index;
FILE* dictfp = NULL;

/**
 * Returns true if word is in dictionary else false.
 */
bool check(const char* word)
{
    // TODO
    return false;
}

/**
 * Loads dictionary into memory.  Returns true if successful else false.
 */
bool load(const char* dictionary)
{
    //root is initailzed as a node.
    root = newNode();
    root->isWord = false;
    length = strlen(dictionary);

    //Open the dictionary
    dictfp = fopen(dictionary, "r");
    //return null if file can't be opened.
    if (dictfp == NULL)
    {
        return false;
    }
    //a traversal pointer equal to root. We'll use only this traversal pointer.
    node* trav = root;

    //loop to iterate through all the words in the dictionary file.
    while(!feof(dictfp))
    {
        fscanf(dictfp, "%s\n", word);
        length = strlen(word);

                for (int i = 0; i < length; i++)
                {
                    c = word[i];
                    index = tolower(c) - 'a';

                    if (trav->children[index] == NULL)
                    {
                        node* newnode = newNode();
                        trav->children[index] = newnode;

                    }else if (trav->children[index] != NULL)
                    {
                     trav = trav->children[index];   
                    }
                    if (c == '\n')
                    {
                        trav->isWord = true;
                    }
                }
    }

    fclose(dictfp);

    return true;
}

/**
 * Returns number of words in dictionary if loaded else 0 if not yet loaded.
 */
unsigned int size(void)
{
    // TODO
    return 0;
}

/**
 * Unloads dictionary from memory.  Returns true if successful else false.
 */
bool unload(void)
{
    // TODO
    return false;
}




////Make a new node function
node* newNode()
{
    node* newnode = calloc(1, sizeof(node));
    //setting all children pointers to NULL.
    for (int i = 0; i < 27; i++)
    {
        newnode->children[i] = NULL;
    }
    return newnode;
}

EDIT: I get "Could not open cat." in terminal if I use the small dictionary and cat as input. Could it be because of only having implemented Load so far.

Answer 1

Your code doesn't handle apostrophes. If the dictionary file has a word with an apostrophe, the index value generated is -58, so trav->children[index] generates a seg fault.

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