uaccess.h

来自「rtlinux-3.2源码」· C头文件 代码 · 共 49 行

#ifndef __COMPAT_ASM_UACCESS_H
#define __COMPAT_ASM_UACCESS_H

#if LINUX_VERSION_CODE < KERNEL_VERSION(2,2,0)
/* unknown, approx 2.1.4 */


#include <asm/segment.h>

static inline int copy_to_user(void * to,const void *from,unsigned long n_bytes)
{
	int i;

	if((i=verify_area(VERIFY_WRITE,to,n_bytes)) != 0)
		return i;
	memcpy_tofs(to,from,n_bytes);
	return 0;
}

static inline int copy_from_user(void * to,const void *from,unsigned long n_bytes)
{
	int i;
	if((i=verify_area(VERIFY_READ,from,n_bytes))!=0)
		return i;
	memcpy_fromfs(to,from,n_bytes);
	return 0;
}

static inline int clear_user(void * mem,unsigned long len)
{
	char *cmem=mem;
	
	if(verify_area(VERIFY_WRITE,mem,len))
		return len;
	/* this is slow, but I'm lazy */
	while(len--){put_user(0,cmem);cmem++;}
	return 0;
}

#else

#include_next <asm/uaccess.h>

#endif

#endif