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/*
* Copyright (C) 2001 Chris Emerson (cemerson@chiark.greenend.org.uk)
* Copyright (C) 2001 Jeff Dike (jdike@karaya.com)
* Licensed under the GPL
*/
#include <string.h>
#include "user_util.h"
#include "uml_uaccess.h"
#include "task.h"
#include "kern_util.h"
#include "os.h"
#include "longjmp.h"
int __do_copy_from_user(void *to, const void *from, int n,
void **fault_addr, void **fault_catcher)
{
struct tt_regs save = TASK_REGS(get_current())->tt;
unsigned long fault;
int faulted;
fault = __do_user_copy(to, from, n, fault_addr, fault_catcher,
__do_copy, &faulted);
TASK_REGS(get_current())->tt = save;
if(!faulted)
return 0;
else if (fault)
return n - (fault - (unsigned long) from);
else
/* In case of a general protection fault, we don't have the
* fault address, so NULL is used instead. Pretend we didn't
* copy anything. */
return n;
}
static void __do_strncpy(void *dst, const void *src, int count)
{
strncpy(dst, src, count);
}
int __do_strncpy_from_user(char *dst, const char *src, unsigned long count,
void **fault_addr, void **fault_catcher)
{
struct tt_regs save = TASK_REGS(get_current())->tt;
unsigned long fault;
int faulted;
fault = __do_user_copy(dst, src, count, fault_addr, fault_catcher,
__do_strncpy, &faulted);
TASK_REGS(get_current())->tt = save;
if(!faulted) return(strlen(dst));
else return(-1);
}
static void __do_clear(void *to, const void *from, int n)
{
memset(to, 0, n);
}
int __do_clear_user(void *mem, unsigned long len,
void **fault_addr, void **fault_catcher)
{
struct tt_regs save = TASK_REGS(get_current())->tt;
unsigned long fault;
int faulted;
fault = __do_user_copy(mem, NULL, len, fault_addr, fault_catcher,
__do_clear, &faulted);
TASK_REGS(get_current())->tt = save;
if(!faulted) return(0);
else return(len - (fault - (unsigned long) mem));
}
int __do_strnlen_user(const char *str, unsigned long n,
void **fault_addr, void **fault_catcher)
{
struct tt_regs save = TASK_REGS(get_current())->tt;
int ret;
unsigned long *faddrp = (unsigned long *)fault_addr;
jmp_buf jbuf;
*fault_catcher = &jbuf;
if(UML_SETJMP(&jbuf) == 0)
ret = strlen(str) + 1;
else ret = *faddrp - (unsigned long) str;
*fault_addr = NULL;
*fault_catcher = NULL;
TASK_REGS(get_current())->tt = save;
return ret;
}
/*
* Overrides for Emacs so that we follow Linus's tabbing style.
* Emacs will notice this stuff at the end of the file and automatically
* adjust the settings for this buffer only. This must remain at the end
* of the file.
* ---------------------------------------------------------------------------
* Local variables:
* c-file-style: "linux"
* End:
*/
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