带有Str的Perl6 NativeCall被编码('utf16')得到随机损坏的结果

Question

我正在GetFullPathName使用perl6脚本映射Windows API NativeCall,因此我写了以下内容:

#!perl6
use NativeCall;
constant \WIN32_MAX_PATH = 260;    

#I may use directly $path.IO.absolute()
sub Win32-GetFullPathName(
        Str $lpFileName is encoded('utf16'),
        int32 $nBufferLength, 
        #Str $lpBuffer is encoded('utf16') is rw,
        Blob $lpBuffer is rw,
        Str $lpFilenameIndex is rw)
    returns int32
    is native('kernel32.dll') 
    is symbol('GetFullPathNameW') 
    { * }


my $path = '.';
my $fp-size = Win32-GetFullPathName(
        $path, # $path ~ "\0", # <!-- this hack make it working fine
        WIN32_MAX_PATH, 
        #my Str $fpath = ' ' x WIN32_MAX_PATH;
        my $buffer = buf16.allocate(WIN32_MAX_PATH), 
        Str );
put "[$fp-size] => ", $buffer.decode('utf16').substr(0, $fp-size);

该代码是随机的工作,直到我一个追加"\0"后$path.

[编辑]多次调用时的结果:

[12] => D:\ dev\pa.t

[12] => D:\ dev\pa.

[12] => D:\ dev \pa.μºƒ

[9] => D:\ dev\pa

[9] => D:\ dev\pa

还有另一种正确的方法吗？

Answer 1

我怀疑 MoarVM 中存在错误src/strings/utf16.c，特别是第 403 行：

result = MVM_realloc(result, *output_size);

这可能应该读

result = MVM_realloc(result, *output_size + 2);

如果您可以验证这是否解决了您的问题，请随时提交错误报告，甚至创建拉取请求。