从XS访问存储在perl对象(祝福散列)中的值

Question

我有一个像这样的perl对象(祝福哈希的引用).

sub funcname {
  #some code
}

my $o = My::Class->new();
$o->{internal_data} = \&funcname; #I know it is not nice

在XS代码中的某个地方,我有$ o引用,我需要获取值$o->{internal_data}.

/* at some point in XS code */
SV *obj = ... /* $o value passed to a XS function */
SV *func;
...
/* here I do not know how to load $o->{internal_data} value into func */
...
call_sv(func,G_SCALAR);

perl中可能还有一些章节(api | xstut | guts | ???).我只是无法找到它.

提前感谢任何提示.

- kmx

Answer 1

SvRV将从SV*引用中获取哈希(作为),MUTABLE_HV将其转换为a HV*,hv_fetch/ hv_fetchs将从哈希中获取.

SV*  self;
SV*  obj_sv;
HV*  obj_hv;
SV** callback_ptr;
SV*  callback;

self = ...;
SvGETMAGIC(self);
if (!SvROK(self))
    croak("Not a reference");

obj_sv = SvRV(self);
if (SvTYPE(obj_sv) != SVt_PVHV)
    croak("Not a reference to a hash");

obj_hv = MUTABLE_HV(obj_sv);

callback_ptr = hv_fetchs(obj_hv, "internal_data", 0);
if (!callback_ptr)
    croak("Malformed object");

callback = *callback_ptr;