F-Kernel Modul

Det (officielle?) fklub kernel modul. Originalt lavet af jokke, mchro & kyrke 2006.

#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/fs.h>
 
#define MAX_Fs 99999 //-1 for infinitet 
 
/* Bør denne ikke være unsigned, ellers er der ikke flere f'er,
   når den wrapper? -mchro (17-02-08) */
int fCount = 0;
 
static int device_open(struct inode *i, struct file *f) 
{
 
	return 0;
}
 
static int device_close(struct inode *i, struct file *f)
{
	return 0;
}
 
static ssize_t device_read(
	struct file *f, char *buffer, size_t length, loff_t *offset)
{
	*buffer = 'F';
	fCount++;
 
	if (fCount != -1 && fCount >= MAX_Fs){
		panic("No more F's");
	}
 
 	return 1;
}
 
static ssize_t device_write(
	struct file *f, const char *buffer, size_t length, loff_t *offset)
{
	if (*buffer = 'F' || *buffer = 'f'){
		fCount--;
	}else{
		panic("My world only contains F!!! ")
	}	
	return length;
}
 
static struct file_operations fops = 
{
	.read = device_read,
	.write = device_write,
	.open = device_open,
	.release = device_close
};
 
static int major;
 
static int device_init(void) 
{
	major = register_chrdev(0, "null device", &fops);
	if (major < 0) 
	{
		printk("Init failed (%d)\n", major);
		return major;
	}
	printk("Got major %d\n", major);
	return 0;
}
 
static void device_exit(void) 
{
	int n = unregister_chrdev(major, "null device");
	if (n < 0) 
	{
		printk("Cleanup failed (%d)\n", n);
	}
}
 
module_init(device_init);
module_exit(device_exit);
 
MODULE_LICENSE("GPL");