apps: Remove demo programs (except for init)

We no longer need those, and they just make the initrd larger.

apps/Makefile

@@ -1,4 +1,4 @@
-APPS := init fib leap art memeater quota
+APPS := init
 
 APPS_DIR := $(LUNA_ROOT)/apps
 APPS_SRC := $(APPS_DIR)/src

apps/src/art.c

@@ -1,18 +0,0 @@
-#include <stdio.h>
-#include <sys/syscall.h>
-#include <unistd.h>
-
-int main()
-{
-    sleep(1);
-
-    syscall(SYS_paint, 0, 0, 400, 300, 0x000000FF);
-
-    sleep(1);
-
-    printf("Hello, colorful world!\n");
-
-    sleep(1);
-
-    printf("Press any key to restart.");
-}

apps/src/fib.c

@@ -1,34 +0,0 @@
-#include <luna.h>
-#include <stdio.h>
-#include <unistd.h>
-
-void fib_next(unsigned long int* a, unsigned long int* b)
-{
-    unsigned long int _a = *a;
-    unsigned long int _b = *b;
-    *a = *b;
-    *b = _a + _b;
-}
-
-int main()
-{
-    unsigned long int fib_a = 1;
-    unsigned long int fib_b = 1;
-
-    printf("Calculating the 50 first Fibonacci numbers...\n");
-
-    sleep(2);
-
-    printf("%lu\n", fib_a);
-
-    msleep(500);
-
-    for (int i = 0; i < 49; i++)
-    {
-        printf("%lu\n", fib_b);
-        fib_next(&fib_a, &fib_b);
-        msleep(500);
-    }
-
-    printf("\nDone, press any key to restart.\n");
-}

apps/src/leap.c

@@ -1,38 +0,0 @@
-#include <luna.h>
-#include <stdio.h>
-#include <sys/syscall.h>
-#include <unistd.h>
-
-unsigned long random_year() // Return a year from 1000 to 2500.
-{
-    unsigned long result = syscall(SYS_rand);
-    return (result % 1500) + 1000;
-}
-
-int is_leap(unsigned long year)
-{
-    return ((year % 4 == 0) && (year % 100 != 0)) || (year % 400 == 0);
-}
-
-int main()
-{
-    printf("Welcome to the Luna Leap Year Program!\n\n");
-
-    sleep(1);
-
-    printf("Choosing a random year between 1000 and 2500... ");
-
-    msleep(500);
-
-    unsigned long year = random_year();
-
-    printf("%lu!\n\n", year);
-
-    sleep(1);
-
-    printf("%lu is %s\n", year, is_leap(year) ? "a leap year!" : "not a leap year :(");
-
-    msleep(500);
-
-    printf("Press any key to restart.\n");
-}

apps/src/memeater.c

@@ -1,21 +0,0 @@
-#include <errno.h>
-#include <stdio.h>
-#include <stdlib.h>
-#include <string.h>
-#include <unistd.h>
-
-#define CHUNK 4194304 // 4 MB
-
-int main()
-{
-    printf("Welcome to memeater! This little program is designed to eat up all the memory on your system.\n");
-    sleep(1);
-    void* allocated = malloc(CHUNK);
-    do {
-        printf("Allocating 4 MB of memory... %p\n", allocated);
-        sleep(1);
-    } while ((allocated = malloc(CHUNK)));
-    printf("Memory allocation failed: %m\n");
-    printf("Press any key to restart.\n");
-    return 1;
-}

apps/src/quota.c

@@ -1,22 +0,0 @@
-#include <fcntl.h>
-#include <stdio.h>
-#include <unistd.h>
-
-int main()
-{
-    if (open("/file/that/does/not/exist", O_RDONLY) < 0) { perror("open"); }
-    int sys = open("/sys", O_RDONLY);
-    if (sys < 0) { perror("open"); }
-    if (read(sys, NULL, 20) < 0) { perror("read"); }
-    char buf[20];
-    if (read(sys, buf, 20) < 0) { perror("read"); }
-    if (close(sys) < 0) { perror("close"); }
-    for (int i = 0; i < 10; i++)
-    {
-        if (open("/", O_RDONLY) < 0) { perror("open"); }
-    }
-    int exec;
-    if ((exec = open("/bin/quota", O_RDONLY)) < 0) { perror("open"); }
-    if (read(exec, buf, 20) < 0) { perror("read"); }
-    if (close(exec) < 0) { perror("close"); }
-}