Perl:Math64 :: Int64应该在“安全”隔间内工作吗?

时间:2012-07-06 22:01:21

标签: perl perl-module

(我的第一篇文章是堆栈溢出,希望我使用正确的格式)

我需要评估在a中操作64位整数的代码 “安全”隔间。因为我提供了脚本和代码 要评估,我可以做一个正常的评估,但我想尝试做 通过使用“安全”来解决无意识错误的问题。

我是否应该期望Math :: Int64在“安全”内正常工作 车厢?我在不同的比特中得到了相互矛盾的结果 Perl版本,整数位宽和操作系统。 (见下文)。

在调试器内部以相同的方式失败。

我确信我在某个地方做了一些不正确的假设,但不能 弄清楚在哪里。

感谢您提供任何帮助。

代码示例(dummy.pl)

use strict;
use warnings;
use Exporter;
use Safe;
use Math::Int64 qw(int64 hex_to_int64);
#use Math::Int64 ':native_if_available';

my $safe = new Safe 'Root';
$safe->permit( qw(:browse) );
$safe->share( qw/int64 hex_to_int64 my_sprintf/ );

my $X = 0xFF & (hex_to_int64("0xAA12345678") >> 4);
print my_sprintf("X ",$X);

my $Z = evalme('$X = 0xFF & (hex_to_int64("0xAA12345678") >> 4)', $safe);
print my_sprintf("Z ",$Z);

print evalme('my_sprintf("Xe", $X)',$safe);

exit;


sub my_sprintf {
    my ($string, $value) = @_;
    return sprintf( "Value of %s: %X,\tType: %s\n",
                    $string, $value, ref($value) || "scalar"
           );
}

sub evalme {
    my($expr, $safe) = @_;
    my $retval = $safe->reval($expr);
    die "Error: $@\n" if ($@);
    return $retval;
}

执行示例

% perl -w dummy.pl

=== "Win7 x64 SP1, Strawberry Perl 5.12.3" ===
Value of X : 67,        Type: Math::Int64
Can't locate package Exporter for @Math::Int64::ISA at (eval 5) line 1.
...
Can't locate package Exporter for @Math::Int64::ISA at (eval 5) line 1.
Value of Z : 67,        Type: Math::Int64
Value of Xe: 67,        Type: Math::Int64

=== "Win XP SP3 32-bit Strawberry Perl 5.16.0" ===
Value of X : 67,        Type: Math::Int64
Value of Z : 8E,        Type: scalar
Value of Xe: 8E,        Type: scalar


(No ':native-if-available')
=== "Ubuntu 10.04 x86_64 Server, Perl 5.10.1" ===
Value of X : 67,        Type: Math::Int64
Value of Z : 4D,        Type: scalar
Value of Xe: 4D,        Type: scalar

(':native-if-available')
=== "Ubuntu 10.04 x86_64 Server, Perl 5.10.1" ===
Value of X : 67,        Type: scalar
Value of Z : 71,        Type: scalar
Value of Xe: 71,        Type: scalar



% perl -wd dummy.pl

All versions return effectively:

Value of X : 67,        Type: Math::Int64
Error: Undefined subroutine &Math::Int64::hex_to_int64 called at c:/.../perl5db.

 at dummy.pl line 35
        main::evalme('$X = 0xFF & (hex_to_int64("0xAA12345678") >> 4)',
                     'Safe=HASH(xxxxxxxx)'

版本

"Win7 x64 SP1, Strawberry Perl 5.12.3":
  Platform:
    osname=MSWin32, osvers=6.1, archname=MSWin32-x64-multi-thread
    uname='Win32 strawberryperl 5.12.3.0 #1 Sun May 15 09:43:50 2011 x64'
    use64bitint=define, use64bitall=undef, uselongdouble=undef
  Compiler:
    intsize=4, longsize=4, ptrsize=8, doublesize=8, byteorder=12345678
    d_longlong=define, longlongsize=8, d_longdbl=define, longdblsize=12
    ivtype='long long', ivsize=8, nvtype='double', nvsize=8, Off_t='long long',
  Characteristics of this binary (from libperl):
     Compile-time options: ... USE_64_BIT_INT

"Win XP 32-bit Strawberry Perl 5.16.0":
  Platform:
    osname=MSWin32, osvers=4.0, archname=MSWin32-x86-multi-thread
    uname='Win32 strawberry-perl 5.16.0.1 #1 Mon May 21 22:07:30 2012 i386'
    use64bitint=undef, use64bitall=undef, uselongdouble=undef
  Compiler:
    intsize=4, longsize=4, ptrsize=4, doublesize=8, byteorder=1234
    d_longlong=undef, longlongsize=8, d_longdbl=define, longdblsize=12
    ivtype='long', ivsize=4, nvtype='double', nvsize=8, Off_t='long long',
  Characteristics of this binary (from libperl):
     Compile-time options: ...

"Ubuntu 10.04 x86_64 Server, Perl 5.10.1":
  Linux 2.6.32-31-server,
  Platform:
    use64bitint=define, use64bitall=define, uselongdouble=undef
  Compiler:
    intsize=4, longsize=8, ptrsize=8, doublesize=8, byteorder=12345678
    d_longlong=define, longlongsize=8, d_longdbl=define, longdblsize=16
    ivtype='long', ivsize=8, nvtype='double', nvsize=8, Off_t='off_t',
  Characteristics of this binary (from libperl):
     Compile-time options: ... USE_64_BIT_ALL USE_64_BIT_INT

1 个答案:

答案 0 :(得分:1)

似乎问题是由于超载无法在安全隔间内工作造成的。

重载是one of the ways以规避安全,因此可能会故意禁用。如果你真的想知道,你可以在perl5-porters邮件列表上询问。

我不认为这可以通过Math :: Int64解决(BTW,我是它的作者)。

另一方面,您可以尝试使用本机64位支持编译Perl。