perl - 使用 XS 返回 Perl 哈希(错误 : 'void' not in typemap)

Question

我正在尝试添加对 Augeas (Config::Augeas) 的 Perl 绑定(bind)的调用。我希望这个新调用返回一个 Perl 哈希。我写了这个:

void                                                               
aug_span(aug, path);
      Config_Augeas* aug
      char* path                      
    PREINIT:                        
      int ret ;                                                          
      char *filename = NULL;                                                                   
      uint label_start, label_end, value_start, value_end, span_start, span_end;
      HV *span_hash;
    CODE:
      ret = aug_span(aug, path, &filename, &label_start, &label_end, &value_start, &value_end, &span_start, &span_end);
      span_hash = newHV();
      hv_store(span_hash, "filename", 8, newSVpv(filename, strlen(filename)), 0);
      hv_store(span_hash, "label_start", 11, newSViv(label_start), 0);
      hv_store(span_hash, "label_end", 9, newSViv(label_end), 0);
      hv_store(span_hash, "value_start", 11, newSViv(value_start), 0);
      hv_store(span_hash, "value_end", 9, newSViv(value_end), 0);     
      hv_store(span_hash, "span_start", 10, newSViv(span_start), 0);
      hv_store(span_hash, "span_end", 8, newSViv(span_end), 0);
      RETVAL = newRV_noinc((SV *)span_hash);
    OUTPUT:
      RETVAL

但是当我构建它时，我得到:

lib/Config/Augeas.xs -> lib/Config/Augeas.c
Use of uninitialized value within %ExtUtils::ParseXS::type_kind in hash element at /usr/share/perl/5.10/ExtUtils/ParseXS.pm line 785, <GEN7> line 170.
Error: 'void' not in typemap in Augeas.xs, line 167
cc -I/usr/lib/perl/5.10/CORE -DXS_VERSION="0.701" -DVERSION="0.701" -fPIC -Wall -Wformat -Werror=format-security -c -D_REENTRANT -D_GNU_SOURCE -DDEBIAN -fno-strict-aliasing -pipe -fstack-protector -I/usr/local/include -D_LARGEFILE_SOURCE -D_FILE_OFFSET_BITS=64 -O2 -g -o lib/Config/Augeas.o lib/Config/Augeas.c
lib/Config/Augeas.xs: In function \u2018XS_Config__AugeasPtr_span\u2019:
lib/Config/Augeas.xs:158: warning: value computed is not used
lib/Config/Augeas.xs:159: warning: value computed is not used
lib/Config/Augeas.xs:160: warning: value computed is not used
lib/Config/Augeas.xs:161: warning: value computed is not used
lib/Config/Augeas.xs:162: warning: value computed is not used
lib/Config/Augeas.xs:163: warning: value computed is not used
lib/Config/Augeas.xs:164: warning: value computed is not used
lib/Config/Augeas.xs:165: error: \u2018RETVAL\u2019 undeclared (first use in this function)
lib/Config/Augeas.xs:165: error: (Each undeclared identifier is reported only once
lib/Config/Augeas.xs:165: error: for each function it appears in.)
error building lib/Config/Augeas.o from 'lib/Config/Augeas.c' at /usr/share/perl/5.10/ExtUtils/CBuilder/Base.pm line 110.

我究竟做错了什么？

Answer 1

试一试:

SV *
aug_span(aug, path);
      Config_Augeas* aug
      char* path                      
    PREINIT:                        
      int ret ;                                                          
      char *filename = NULL;                                                                   
      uint label_start, label_end, value_start, value_end, span_start, span_end;
      HV *span_hash;
    CODE:
      ret = aug_span(aug, path, &filename, &label_start, &label_end, &value_start, &value_end, &span_start, &span_end);
      span_hash = newHV();
      hv_store(span_hash, "filename", 8, newSVpv(filename, strlen(filename)), 0);
      hv_store(span_hash, "label_start", 11, newSViv(label_start), 0);
      hv_store(span_hash, "label_end", 9, newSViv(label_end), 0);
      hv_store(span_hash, "value_start", 11, newSViv(value_start), 0);
      hv_store(span_hash, "value_end", 9, newSViv(value_end), 0);     
      hv_store(span_hash, "span_start", 10, newSViv(span_start), 0);
      hv_store(span_hash, "span_end", 8, newSViv(span_end), 0);
      RETVAL = sv_2mortal((SV*)newRV_noinc((SV *)span_hash));
    OUTPUT:
      RETVAL

变化是:返回类型(void => SV*)，我在返回的 SV* 上使用 sv_2mortal。由于堆栈没有被引用计数，因此必须在下一个“合适的”机会时将 SV* 标记为销毁。