Hello Seekers of Perl Wisdom,

I try to make a perl binding to the following struct

struct _Edje_Message_String_Set
{
   int count;
   char *str[1];
};

[download]

At the moment my try of an implementation looks like this (only the important parts):

[...]
typedef Edje_Message_String_Set EdjeMessageStringSet;

MODULE = pEFL::Edje::Message::StringSet        PACKAGE = pEFL::Edje::M
+essage::StringSet

EdjeMessageStringSet *
_new(class,count, val_arr)
    char *class
    int count
    AV *val_arr
PREINIT:
    EdjeMessageStringSet *message;
    int index;
    char *string;
    STRLEN len;
CODE:
    message = malloc(sizeof(Edje_Message_String) + count * sizeof(char
+ *));
    message->count = count+1;
    for (index = 0; index <= count; index++) {
        SV *tmp = *av_fetch(val_arr,index,0);
        string = SvPVutf8(tmp,len);
        message->str[index] = savepvn(string,len);
    }
    RETVAL = message;
OUTPUT:
    RETVAL

MODULE = pEFL::Edje::Message::StringSet        PACKAGE = EdjeMessageSt
+ringSetPtr

[...]
    
void
str(message)
    EdjeMessageStringSet *message
PREINIT:
    int count;
    char **vals;
    int index;
PPCODE:
    count = message->count;
    vals = message->str;
    
    EXTEND(SP,count);
    for (index = 0; index <count; index ++) {
        PUSHs( sv_2mortal( newSVpv( vals[index], 0 ) ));
    }

void
DESTROY(message) 
    EdjeMessageStringSet *message
CODE:
    free(message);

[download]

Unfortunately I get different errors (e.g. corrupted size vs. prev_size, double_free or corruption (out), segfault, invalid pointer etc.). Following a simple test code:

use pEFL::Edje::Message::StringSet;

my $i = 0;
while ($i<100) {
    my @str = ("Hello", "Wordl", "from Perl");
    my $str_msg = pEFL::Edje::Message::StringSet->new(@str);
    my @strings = $str_msg->str();
    print "COLORS @strings\n";
    $i++;
}

print "The script goes to the end\n";

[download]

Where is my misunderstanding?

PS:

I tried to use perl XS memory allocation, too. But this doesn't help. For example the following doesn't work:

PREINIT:
    [...]
    char **val;
CODE:
    New(0,val,count+1, char*);
    New(0,message,1,EdjeMessageStringSet);
    message->count = count+1;
    for (index = 0; index <= count; index++) {
        SV *tmp = *av_fetch(val_arr,index,0);
        string = SvPVutf8(tmp,len);
        New(0,val[index],len,char)
        val[index] = savepvn(string,len);
    }
    Move(val,message->str,count+1,char*);
    RETVAL = message;
OUTPUT:
    RETVAL

[download]

btw. how can one allocate memory in Perl XS with size calculated from different types (here Edje_Message_Signal_Set and char(*))?

Thank you so much for your help!!!

Max

In reply to Perl XS binding to a struct with an array of chars* by MaxPerl

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