Insertion sort in linked list

Write a program for insertion sort in linked list in C

struct lnode {

            char *str;

            struct lnode *next;

};

struct lnode *insert(char *data, struct lnode *list);

void free_list(struct lnode *list);

void print_list(struct lnode *list);

int main(void) {

            char line[1024];

            struct lnode *list;

            list = NULL;

            while((fgets(line, 1024, stdin)) != NULL)

                        list = insert(line, list);

            print_list(list);

            free_list(list);

            return 0;

}

struct lnode *insert(char *data, struct lnode *list) {

            struct lnode *p;

            struct lnode *q;

            /* create a new node */

            p = (struct lnode *)malloc(sizeof(struct lnode));

            /* save data into new node */

            p->str = strdup(data);

            /* first, we handle the case where `data' should be the first element */

            if(list == NULL || strcmp(list->str, data) > 0) {

                        /* apperently this !IS! the first element */

                        /* now data should [be|becomes] the first element */

                        p->next = list;

                        return p;

            } else {

                        /* search the linked list for the right location */

                        q = list;

                        while(q->next != NULL && strcmp(q->next->str, data) < 0) {

                                    q = q->next;

                        }

                        p->next = q->next;

                        q->next = p;

                        return list;

            }

}

void free_list(struct lnode *list) {

            struct lnode *p;

            while(list != NULL) {

                        p = list->next;

                        free(list);

                        list = p;

            }

}

void print_list(struct lnode *list) {

            struct lnode *p;

            for(p = list; p != NULL; p = p->next)

                        printf("%s", p->str);

}