Hello!

I have to investigate the functionality of a C library and while in the past I always used SWIG to interface with C/C++ code, I am now trying to use Inline::C instead to save time on the "interface compilation" phase, seen that I'm only interested in experimenting with the C functions and copy/paste is not a problem.

All is good except I don't see how to "pass a NULL pointer from Perl". SWIG resolves by passing undef but Inline::C explodes on that, e.g.:

use v5.10;

use Inline 'C';

say "At least we have compiled a bit of C code!";

my $ret= "HD3";
my $output = enctypex_msname("HD2", undef);

say "Output from enctypex_msname() call: '$output', \$ret is '$ret'";

__END__
__C__
unsigned char *enctypex_msname(unsigned char *name, unsigned char *ret
+name) {
    static unsigned char    msname[256];
    unsigned    i,
                c,
                server_num;

    if(!name) return(NULL);

    server_num = 0;
    for(i = 0; name[i]; i++) {
        c = tolower(name[i]);
        server_num = c - (server_num * 0x63306ce7);
    }
    server_num %= 20;

    if(retname) {
        snprintf(retname, 256, "%s.ms%d.host.com", name, server_num);
        return(retname);
    }
    snprintf(msname, sizeof(msname), "%s.ms%d.host.com", name, server_
+num);
    return(msname);
}
[download]

This results in:

At least we have compiled a bit of C code!
Use of uninitialized value in subroutine entry at script/decode_test.pl line 12.
Segmentation fault (core dumped)

I see that SWIG provides some custom type mappings for all the bindings, so unless I re-use those I am probably out of luck and have to write one for my use case? I wonder how it comes that nobody has ever had to pass a NULL pointer or have I overlooked something in Inline::* docs ?
Any hints?

---

---

• Are you posting in the right place? Check out Where do I post X? to know for sure.
• Posts may use any of the Perl Monks Approved HTML tags. Currently these include the following:

  <code> <a> <b> <big> <blockquote> <br /> <dd> <dl> <dt> <em> <font> <h1> <h2> <h3> <h4> <h5> <h6> <hr /> <i> <li> <nbsp> <ol> <p> <small> <strike> <strong> <sub> <sup> <table> <td> <th> <tr> <tt> <u> <ul>

• Snippets of code should be wrapped in <code> tags not <pre> tags. In fact, <pre> tags should generally be avoided. If they must be used, extreme care should be taken to ensure that their contents do not have long lines (<70 chars), in order to prevent horizontal scrolling (and possible janitor intervention).
• Want more info? How to link or How to display code and escape characters are good places to start.