Beefy Boxes and Bandwidth Generously Provided by pair Networks
Do you know where your variables are?
 
PerlMonks  

comment on

( [id://3333]=superdoc: print w/replies, xml ) Need Help??
Hi MaxPerl,

It looks to me that:
typedef Edje_Message_String_Set EdjeMessageStringSet; should instead be: typedef struct _Edje_Message_String_Set EdjeMessageStringSet;
Also the following looks wrong to me:
message = malloc(sizeof(Edje_Message_String) + count * sizeof(char *)) +;
The variable "message" is a pointer to a EdjeMessageStringSet type, and memory should be assigned to it as:
message = malloc(sizeof(EdjeMessageStringSet)); or New(0, message, 1, EdjeMessageStringSet); or (in modern perl) Newx(message, 1, EdjeMessageStringSet);
I recommend working your way through the various issues using Inline::C.
It's not a quick fix but, as you become familiar with it, it enables you to test out various options.
It also enables you to post a demo script of problems you are facing. Others can then run that demo to reproduce (and hopefully assist with) the issue.

Here's a little Inline::C demonstrating some basics:
# struct.pl # use strict; use warnings; use Inline C => Config => BUILD_NOISY => 1, CLEAN_AFTER_BUILD => 0, USING => 'ParseRegExp', ; use Inline C => <<'EOC'; struct _Edje_Message_String_Set { int count; char *str[1]; }; typedef struct _Edje_Message_String_Set EdjeMessageStringSet; void struct_size(void) { printf("Size of _Edje_Message_String_Set struct: %d\n", sizeof(EdjeMessageStringSet) ); } EdjeMessageStringSet * _new(char * class, int count, AV * val_arr) { /* Can't be accessed directly from perl unless a typemap is provided */ EdjeMessageStringSet *message; int index; char *string; STRLEN len; Newx(message, 1, EdjeMessageStringSet); if(message == NULL) croak("Failed to allocate memory in _new function"); /* do other stuff ... */ printf("returning EdjeMessageStringSet* from _new\n"); return message; } void DESTROY(EdjeMessageStringSet * x) { /* Can't be accessed directly from perl unless a typemap is provided. Must currently be explicitly called as the EdjeMessageStringSet* object is currently "unblessed". */ Safefree(x); printf("destroyed _new EdjeMessageStringSet*\n"); } void foo(char * pv, int in, AV * arref) { EdjeMessageStringSet *m; m = _new(pv, in, arref); DESTROY(m); } EOC struct_size(); foo("hello world", 2, [1, 2]);
After the script has been compiled, it outputs (for me):
Size of _Edje_Message_String_Set struct: 16 returning EdjeMessageStringSet* from _new destroyed _new EdjeMessageStringSet*
If you look in the ./_Inline/build/ directory you'll find a folder that contains (amongst other things) the XS file that Inline::C automatically generated and used.

Cheers,
Rob

In reply to Re: Perl XS binding to a struct with an array of chars* by syphilis
in thread Perl XS binding to a struct with an array of chars* by MaxPerl

Title:
Use:  <p> text here (a paragraph) </p>
and:  <code> code here </code>
to format your post; it's "PerlMonks-approved HTML":



  • 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.
Log In?
Username:
Password:

What's my password?
Create A New User
Domain Nodelet?
Chatterbox?
and the web crawler heard nothing...

How do I use this?Last hourOther CB clients
Other Users?
Others having a coffee break in the Monastery: (4)
As of 2024-03-28 22:26 GMT
Sections?
Information?
Find Nodes?
Leftovers?
    Voting Booth?

    No recent polls found