if (request.handle == 0) 
if (request.handle == NULL) 
int drm_getsareactx(struct inode *inode, struct file *filp,		    unsigned int cmd, unsigned long arg){	drm_file_t *priv = filp->private_data;	drm_device_t *dev = priv->head->dev;	drm_ctx_priv_map_t __user *argp = (void __user *)arg;	drm_ctx_priv_map_t request;	drm_map_t *map;	drm_map_list_t *_entry;	if (copy_from_user(&request, argp, sizeof(request)))		return -EFAULT;	down(&dev->struct_sem);	if (dev->max_context < 0	    || request.ctx_id >= (unsigned)dev->max_context) {		up(&dev->struct_sem);		return -EINVAL;	}	map = dev->context_sareas[request.ctx_id];	up(&dev->struct_sem);	request.handle = 0;	list_for_each_entry(_entry, &dev->maplist->head, head) {		if (_entry->map == map) {			request.handle =			    (void *)(unsigned long)_entry->user_token;			break;		}	}	if (request.handle == 0)		return -EINVAL;	if (copy_to_user(argp, &request, sizeof(request)))		return -EFAULT;	return 0;}
4520	/local/tlutelli/issta_data/temp/c/2005_temp/2005/4520/b3a83639895a422b25f72eec0a5d1d88c3ac4e9e/drm_context.c/clean/drivers/char/drm/drm_context.c