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Re: Inline::C : passing parameters to functions, modifying by reference

by perlfan (Vicar)
on Jul 23, 2021 at 21:59 UTC ( #11135352=note: print w/replies, xml ) Need Help??


in reply to Inline::C : passing parameters to functions, modifying by reference

I know this is a minor nit and doesn't address your actual question, but I find this style of including the C code (or whatever) to Inline::C to be easier to read and maintain (example untested, but basically using your original code in OP),
use Inline ( C => 'DATA', BUILD_NOISY => 1, clean_after_build => 0, warnings => 10, ); # perl stuff # more perl stuff... __DATA__ __C__ #include <stdio.h> // checks if array is indeed an arrayref and sets array_sz to its size + and // returns 1 else returns 0 (not an array) int is_array_ref( SV *array, size_t *array_sz ){ if( ! SvROK(array) ){ fprintf(stderr, "is_array_ref() : warning, i +nput '%p' is not a reference.\n", array); return 0; } if( SvTYPE(SvRV(array)) != SVt_PVAV ){ fprintf(stderr, "is_array_r +ef() : warning, input ref '%p' is not an ARRAY reference.\n", array); + return 0; } // it's an array, cast it to AV to get its len via av_len(); // yes, av_len needs to be bumped up, it's $#array int asz = 1+av_len((AV *)SvRV(array)); if( asz < 0 ){ fprintf(stderr, "is_array_ref() : error, input arra +y ref '%p' has negative size!\n", array); return 0; } *array_sz = (size_t )asz; return 1; // success, it is an array and size returned by ref, abo +ve } int func( SV *inp, SV *out ){ AV *av, *av2; size_t i, j, asz; if( is_array_ref(out, &asz) ){ printf("Case1: @out\n"); // we have an \@R, e.g. func(\@R) av = (AV *)SvRV(out); // but first clear any contents if( asz > 0 ) av_clear(av); } else if( SvROK(out) ){ printf("Case3: \\$out\n"); // we have a scalar ref, e.g. func(\$x) av = newAV(); sv_setsv(SvRV(out), (SV *)av); } else { printf("Case2: $out\n"); // we have a scalar e.g func($x); av = newAV(); sv_setsv(out, (SV *)av); } // and fill it in for(i=0;i<5;i++){ av2 = newAV(); av_extend(av2, 3); av_push(av, (SV *)av2); for(j=0;j<3;j++){ av_store(av2, j, newSViv(42)); } } return 0; // success }
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Re^2: Inline::C : passing parameters to functions, modifying by reference
by bliako (Monsignor) on Jul 27, 2021 at 22:22 UTC

    ... BUT!

    use strict; use warnings; use Inline C => "DATA"; xyz(); __DATA__ __C__ xyz(); __DATA__ __C__ #define __XX__ unsigned __XX__ int xyz(){ printf("hhaahah\n"); return 1; }
    Undefined subroutine &main::xyz called at a.pl line 8.

    removing any of the underscores in __XX__ fixes the problem.

    whereas this does not have a problem:

    use strict; use warnings; use Inline(C => <<'EOC'); #define __XX__ unsigned __XX__ int xyz(){ printf("hhaahah\n"); return 1; } EOC xyz();

    I am neat-picking because in some of my usage, a 3rd party insists on typedef a __global__ and that messes up the whole inlining. But #define GLOBAL __global__ is a workaround.

    bw, bliako

Re^2: Inline::C : passing parameters to functions, modifying by reference
by bliako (Monsignor) on Jul 26, 2021 at 12:08 UTC

    that's a good suggestion thanks

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