sysfile.ed

在x86平台上运行不可信任代码的sandbox。

,s!lock(f)!lock(\&f->ref.lk)!g
,s!lock(c)!lock(\&c->ref.lk)!g
,s!ref(c)!ref(\&c->ref)!g
,s!^read(!doread(!
,s!return read(!return doread(!g
/use varargs/,/va_end/c
	// Plan 9 VX replaced dodgy varargs code
	v = *(vlong*)&arg[3];
.
,s!^write(!dowrite(!
,s!return write(!return dowrite(!g
/use varargs/,/va_end/c
	// Plan 9 VX replaced dodgy varargs code
	v = *(vlong*)&arg[3];
.
/^bindmount/ s/int ismount/int isk, int ismount/
.-1i
	// Plan 9 VX added isk parameter.
.
,s/return bindmount(/return bindmount(0, /g
g/^sys_/ s/ulong \*)/ulong *u)/
/^bindmount/,/^sysbind/ s/validaddr/if(!isk) validaddr/
/^bindmount/,/^sysbind/ s/spec = validnamedup/if(isk) kstrdup(\&spec, spec); else &/
$a

// Plan 9 VX additions
long
kbind(char *new, char *old, int flag)
{
	return bindmount(1, 0, -1, -1, new, old, flag, nil);
}

long
syspassfd(ulong *u)
{
	error("passfd unimplemented");
	return -1;
}

.
g/va_list/d