在 C 的 struct 链表中添加一个 struct

Question

I need to write software that gets structure from the user (name, path and time) and then add the structure to the end of a linked list. I wrote two functions that work the problem that it only works in the first run, if the user tries to add another structure to the linked program the program crashes): Can anyone help me understand what the problem is? Thank you: These are the structures I created:

// Frame struct
typedef struct Frame
{
    char* name;
    int duration;
    char* path;

} Frame;


// Link (node) struct
typedef struct FrameNode
{
    Frame* frame;
    struct FrameNode* next;
} FrameNode;

What are the functions:

FrameNode* addFrame(Frame frame)
{
    FrameNode* p = malloc(sizeof frame);
    printf("*** Creating a new frame ***\n");
    printf("Please insert frame path:\n");
    p->frame->path = (char*)malloc(sizeof(char*) * 100);
    fgets(p->frame->path, 100, stdin);
    p->frame->path[strcspn(p->frame->path, "\n")] = 0;
    printf("Please insert frame duration <in miliseconds>:\n");
    scanf_s("%d", &(p->frame->duration));
    getchar();
    printf("Please chooce a name for a new frame:\n");
    p->frame->name = (char*)malloc(sizeof(char*) * 100);
    fgets(p->frame->name, 100, stdin);
    p->frame->name[strcspn(p->frame->name, "\n")] = 0;
    while (list != NULL)
    {
        while (strcmp(list->frame->name, p->frame->name) == 0)
        {
            printf("The name is already taken, Please enter another name\n");
            fgets(p->frame->name, 100, stdin);
        }
    }
    p->next = NULL;
    return p;
}

FrameNode* insertAtEnd(FrameNode* list, Frame fr)
{
    FrameNode* tmp = addFrame(fr);
    if (list != NULL)
    {
        list = list->next;
    }
    list = tmp;
    return list;
}

Answer 1

The problem is here-

if (list != NULL)
    {
        list = list->next;
    }
    list = tmp;

Correct one is

while(list>next != NULL)
    {
        list = list->next;
     }
    list->next = tmp;

This will go to next until the last frame and add the new frame. In your code, it works first time because it only executes list=tmp. For other times, we are not going to the end of the list to add tmp. Note if instead of while. Also, in your code when list becomes NULL, we lose address of last frame, so we need the loop till list>next!=NULL instead of list!=NULL .