chessgui has asked for the wisdom of the Perl Monks concerning the following question:

I've managed to put together an XS module which is an interface to the Windows MessageBox function (my ultimate goal is to speak to the System Tray). The XS code: 
#include "EXTERN.h"
#include "perl.h"
#include "XSUB.h"
#include "ppport.h"

#include "windows.h"

MODULE = Mytest    PACKAGE = Mytest

int
hello(input)
unsigned int input
    CODE:
        int x=MessageBox(NULL,TEXT("Text"),TEXT("Caption"),input);
        
        RETVAL=x;
    OUTPUT:
        RETVAL

[download]
This code works. However if I want to use the 'UINT' data type (which is in the original declaration of the function) instead of 'unsigned int' the make fails: 
Error: 'UINT' not in typemap in Mytest.xs, line 12
Please specify prototyping behavior for Mytest.xs (see perlxs manual)

[download]
The perlxs manual says that prototypes can be enabled and disabled but I find no guidance for how to use a predefined C prototype.

Replies are listed 'Best First'.
Re: Prototype problem for XS module
by syphilis (Archbishop) on Feb 05, 2012 at 18:40 UTC
    I suspect you'll fix the problem with UINT if you just have a file named 'typemap'(located in the same directory as the xs file) that contains simply: 
    UINT T_UV

    [download]
    That should tell perl to treat "UINT" as a "T_UV" (unsigned int) .... and perl knows all about the "T_UV" type and how to deal with it, courtesy of perl/lib/ExtUtils/typemap.

    (Btw, you don't need to include windows.h - it has already been pulled in by perl.h.)

    Here's a little Inline::C demo that works only if said typemap is present: 
    # try.pl
use warnings;
use strict;

use Inline C => Config =>
    BUILD_NOISY => 1;

use Inline C =><<'EOC';

UINT hello() {
  UINT x = 17;
  return x;
}


EOC

$x = hello();
print $x; 

# On Windows:
# Outputs 17 if typemap is present,
# Otherwise outputs "Undefined subroutine &main::hello called at try.p
+l line 16."

    [download]



    Cheers,
    Rob
[reply]
[d/l]
[select]
      Fair enough. It works with my XS code as well. (Also true that windows.h is pulled in by default.)

      Now my main problem with NOTIFYICONDATA itself that it needs a hWnd parameter. In other words if I want to have a notify icon I have to have a main window. Currently I have a standalone application which creates a notify icon: 
      int WINAPI WinMain(HINSTANCE hInstance, HINSTANCE hPrevInstance, LPSTR
+ lpCmdLine, int nCmdShow)
{
    INITCOMMONCONTROLSEX icc;
    WNDCLASSEX wc;
    LPCTSTR MainWndClass = TEXT("Template");
    HWND hWnd;
    HACCEL hAccelerators;
    HMENU hSysMenu;
    MSG msg;

    // Initialise common controls.
    icc.dwSize = sizeof(icc);
    icc.dwICC = ICC_WIN95_CLASSES;
    InitCommonControlsEx(&icc);

    // Class for our main window.
    wc.cbSize            = sizeof(wc);
    wc.style            = 0;
    wc.lpfnWndProc            = &MainWndProc;
    wc.cbClsExtra            = 0;
    wc.cbWndExtra            = 0;
    wc.hInstance             = hInstance;
    wc.hIcon            = (HICON) LoadImage(hInstance, MAKEINTRESOURCE
+(IDI_APPICON), IMAGE_ICON, 0, 0, LR_SHARED);
    wc.hCursor            = (HCURSOR) LoadImage(NULL, IDC_ARROW, IMAGE
+_CURSOR, 0, 0, LR_SHARED);
    wc.hbrBackground        = (HBRUSH) (COLOR_BTNFACE + 1);
    wc.lpszMenuName            = MAKEINTRESOURCE(IDR_MAINMENU);
    wc.lpszClassName        = MainWndClass;
    wc.hIconSm            = (HICON) LoadImage(hInstance, MAKEINTRESOUR
+CE(IDI_APPICON), IMAGE_ICON, 16, 16, LR_SHARED);

    // Register our window classes, or error.
    if (! RegisterClassEx(&wc))
    {
        MessageBox(NULL, TEXT("Error registering window class."), TEXT
+("Error"), MB_ICONERROR | MB_OK);
        return 0;
    }
    
    // Create instance of main window.
    hWnd = CreateWindowEx(0, MainWndClass, MainWndClass, WS_OVERLAPPED
+WINDOW, CW_USEDEFAULT, CW_USEDEFAULT,
                                                320, 200, NULL, NULL, 
+hInstance, NULL);

    // Error if window creation failed.
    if (! hWnd)
    {
        MessageBox(NULL, TEXT("Error creating main window."), TEXT("Er
+ror"), MB_ICONERROR | MB_OK);
        return 0;
    }
    
    // Create notify icon

    NOTIFYICONDATA nid;

    nid.cbSize = sizeof(NOTIFYICONDATA);
    nid.hWnd = hWnd;
    nid.uID = 100;
    nid.uVersion = NOTIFYICON_VERSION;
    nid.uCallbackMessage = WM_MYMESSAGE;
    nid.hIcon = LoadIcon(NULL, IDI_APPLICATION);

    wcscpy(nid.szTip, TEXT("Notify Icon"));

    nid.uFlags = NIF_MESSAGE | NIF_ICON | NIF_TIP;
     
    Shell_NotifyIcon(NIM_ADD, &nid);

    // Load accelerators.
    hAccelerators = LoadAccelerators(hInstance, MAKEINTRESOURCE(IDR_AC
+CELERATOR));

    // Add "about" to the system menu.
    hSysMenu = GetSystemMenu(hWnd, FALSE);
    InsertMenu(hSysMenu, 5, MF_BYPOSITION | MF_SEPARATOR, 0, NULL);
    InsertMenu(hSysMenu, 6, MF_BYPOSITION, ID_HELP_ABOUT, TEXT("About"
+));

    // Show window and force a paint.
    ShowWindow(hWnd, nCmdShow);
    UpdateWindow(hWnd);

    // Main message loop.
    while(GetMessage(&msg, NULL, 0, 0) > 0)
    {
        if (! TranslateAccelerator(msg.hwnd, hAccelerators, &msg))
        {
            TranslateMessage(&msg);
            DispatchMessage(&msg);
        }
    }
    
    // Finished so withdraw notify icon
    
    Shell_NotifyIcon(NIM_DELETE, &nid);

    return (int) msg.wParam;
}

      [download]
      However in the XS code I guess I can't have a WinMain function.
[reply]
[d/l]
[reply]
Re: Prototype problem for XS module
by BrowserUk (Patriarch) on Feb 05, 2012 at 17:15 UTC

    Not an answer to your XS problem, but ActiveState Perl comes with the message box call built-in. Try this:

    perl -MWin32 -E"say'The man, he say: ',Win32::MsgBox('Is this what you
+ are after?',4,'Just a question')==6 ?'yes':'no'"

    [download]
    With the rise and rise of 'Social' network sites: 'Computers are making people easier to use everyday'
    Examine what is said, not who speaks -- Silence betokens consent -- Love the truth but pardon error.
    "Science is about questioning the status quo. Questioning authority".
    In the absence of evidence, opinion is indistinguishable from prejudice.

    The start of some sanity?
[reply]
[d/l]
      Thanks a lot. I used to be an ActiveState customer. Recently I switched to Strawberry since it seemed (and later proved) to be more capable of installing CPAN modules. However I feel more and more that the functionality of even CPAN modules is limited when it comes to interfaces to Windows API. (For example in the Win32::GUI module when I speak to the System Tray a bubble pops up which makes a noise - I don't want this noise). Ceterum censeo there is a need to do it myself and make API calls directly through XS code.
[reply]
        Thanks a lot. I used to be an ActiveState customer. Recently I switched to Strawberry

        Well, Win32 is a CPAN module too.

        (For example in the Win32::GUI module when I speak to the System Tray a bubble pops up which makes a noise - I don't want this noise).

        The audible alert is a OS user interface feature, not an application feature. That is, a windows user can elect to turn off audible alerts -- it's about the first thing I do when I do a new install -- or not. But it is, and should be, the application users choice to have audible alerts, not the application writers.

        Ceterum censeo there is a need to do it myself and make API calls directly through XS code.

        Learning XS is not a bad thing to do. Though you may well find it a frustrating exercise.

        With the rise and rise of 'Social' network sites: 'Computers are making people easier to use everyday'
        Examine what is said, not who speaks -- Silence betokens consent -- Love the truth but pardon error.
        "Science is about questioning the status quo. Questioning authority".
        In the absence of evidence, opinion is indistinguishable from prejudice.

        The start of some sanity?
[reply]
Re: Prototype problem for XS module
by Anonymous Monk on Feb 05, 2012 at 16:16 UTC
[reply]
[d/l]
      I'm new to XS programming. I've tried to declare the 'uType' input field to the function as 'UINT' (since this is the way in C the function is declared): 
      int WINAPI MessageBox(
  __in_opt  HWND hWnd,
  __in_opt  LPCTSTR lpText,
  __in_opt  LPCTSTR lpCaption,
  __in      UINT uType
);

      [download]
      My first impression from the error message was that I'm completely forbidden to use windows.h declared data types. Now I see that I can use them safely _inside_ a function. The problem only arises with the declaration and passing of args to the function (which is not a big deal: I want to pass only very simple input to the sub, rather use complicated types like NOTIFYICONDATA inside the sub).
[reply]
[d/l]
Re: Prototype problem for XS module
by Anonymous Monk on Feb 05, 2012 at 16:18 UTC
[reply]
[d/l]

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