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| #define BUF_SIZE 0x100
enum book_status{
CREATED = 0X12345,
ABANDONED = 0X67890,
}
;
typedef struct {
char content[BUF_SIZE];
int status;
} notebook;
notebook * notebooks[10] = {NULL};
void init()
{
setvbuf(stdin, 0, 2, 0);
setvbuf(stdout, 0, 2, 0);
setvbuf(stderr, 0, 2, 0);
}
int read_int()
{
char buf[0x10];
read(0, buf, 0x10);
return atoi(buf);
}
void read_flag()
{
char flag[0x100];
int fd, size = 0;
fd = open("/flag", 0);
if (fd < 0) {
puts("Open flag failed");
exit(-1);
}
size = read(fd, flag, 0x100);
write(1, flag, size);
close(fd);
exit(0);
}
void create_notebook()
{
notebook *book = NULL;
int idx;
puts("Input your notebook index:");
idx = read_int();
if (idx < 0 || idx >= 0x20) {
puts("Invalid index for notebooks, Hacker!");
return;
}
book = malloc(sizeof(notebook));
if (book == NULL) {
puts("malloc error");
exit(-1);
}
puts("Input your notebook content:");
read(0, book->content, BUF_SIZE);
book->status = CREATED;
notebooks[idx] = book;
puts("Done!");
}
void edit_notebook()
{
int idx;
puts("Input your notebook index:");
idx = read_int();
if (idx < 0 || idx >= 0x10) {
puts("Invalid index, Hacker!");
return;
}
if (notebooks[idx] == NULL) {
puts("You don't have this notebook, create it first");
return;
}
notebooks[idx]->status = ABANDONED;
puts("Done!");
}
void delete_notebook()
{
int idx;
puts("Input your notebook index:");
idx = read_int();
if (idx < 0 || idx >= 0x10) {
puts("Invalid index, Hacker!");
return;
}
if (notebooks[idx] == NULL) {
puts("You don't have this notebook, create it first");
return;
}
free(notebooks[idx]);
puts("Done!");
}
void show_notebook()
{
int idx;
puts("Input your notebook index:");
idx = read_int();
if (idx < 0 || idx >= 0x10) {
puts("Invalid index, Hacker!");
return;
}
if (notebooks[idx] == NULL) {
puts("You don't have this notebook, create it first");
return;
}
printf("content = %s, status = 0x%x\n", notebooks[idx]->content, notebooks[idx]->status);
}
int bypass_me()
{
int flag = 0;
if ((notebooks[0] == NULL) ||
(strcmp(notebooks[0]->content, "hello ") != 0) ||
(notebooks[0]->status != CREATED))
return flag;
if ((notebooks[1] == NULL) ||
(strcmp(notebooks[1]->content, "world,") != 0) ||
(notebooks[1]->status != ABANDONED))
return flag;
if ((notebooks[3] == NULL) ||
(strcmp(notebooks[3]->content, "magic ") != 0) ||
(notebooks[3]->status != CREATED))
return flag;
if ((notebooks[5] == NULL) ||
(strcmp(notebooks[5]->content, "notebook") != 0) ||
(notebooks[5]->status != ABANDONED))
return flag;
flag = 1;
return flag;
}
void menu()
{
puts("1. Create Notebook");
puts("2. Edit Notebook");
puts("3. Delete Notebook");
puts("4. Show Notebook");
puts("5. Gift for You");
puts("Choice >> ");
}
int main()
{
int choice, flag = 1;
init();
puts("We have a magic notebook for you:");
while (flag) {
menu();
scanf("%d", &choice);
switch (choice)
{
case 1:
create_notebook();
break;
case 2:
edit_notebook();
break;
case 3:
delete_notebook();
break;
case 4:
show_notebook();
break;
case 5:
if (bypass_me())
read_flag();
flag = 0;
break;
default:
puts("Invalid choice");
break;
}
}
puts("Bye bye~");
return 0;
}
|