OpenEuphoria

1. win32lib et multitasking

• Posted by chadal <francois.chadal at girce.caisse-epargne.fr> Nov 08, 2006
• 1084 views

My project uses Euphoria 3.0.1 and win32lib. Recently, i've insert multi-taking
functions (task_create, task_schedule, task_suspend and task_yield). Since this
update, i've often this kind of error i've never seen before multi-tasking
version.

Why there is no value ?!? for parms and funcid parameters !?!

How can i help to analyse this trouble ?

Are there some restrictions of using task_yield in main task ?


François Chadal


---------------------- TASK ID 0 initial task ----------------------------
D:\EUPHORIA\Biblio\win32lib\Include\w32dll.ew:283 in procedure w32Proc() 
A machine-level exception occurred during execution of this statement 
    funcid = <no value>
    parms = <no value>
    libfunc = <no value>
    lFuncDef = <no value>
    memset = <no value>
    i = <no value>

... called from D:\EUPHORIA\Biblio\win32lib\Include\Win32Lib.ew:33346 in
procedure eventLoop()
    pData = {}
    temp = <no value>
    msg = 10474436
    getRC = 1
    inc = <no value>
    el = 1
    lTock = 0

... called from D:\EUPHORIA\Biblio\win32lib\Include\Win32Lib.ew:33553 in
procedure WinMain()
    id = 3
    style = 0
    lInitFocus = -1
    lRtnId = <no value>
    lEventName = <no value>
    lInitView = <no value>
    i = <no value>

... called from D:\EUPHORIA\ose\bin\winOSE.exw:541 

global procedure w32Proc(atom funcid, sequence parms)
    atom libfunc
    object lFuncDef

    atom memset

    memset = 0
    for i = 1 to length(parms) do
        if sequence(parms[i]) then
            if memset = 0 then
                memset = w32new_memset()
            end if
            parms[i] = w32acquire_mem(memset, parms[i])
        end if
    end for


    if funcid > kMagicRtnID then
    funcid -= kMagicRtnID
    if funcid <= length(vw32Routines) then
        lFuncDef = vw32Routines[funcid]

        if sequence(lFuncDef) then
        if lFuncDef[1] < 0 then
            lFuncDef[1] = -lFuncDef[1]
            if vw32Libraries[lFuncDef[1]][1][1] = 0 then
            vw32Libraries[lFuncDef[1]][1] =
                linkDLL(vw32Libraries[lFuncDef[1]][2])
            end if
            lFuncDef[1] = vw32Libraries[lFuncDef[1]][1][2]
        end if

        lFuncDef = linkProc(    lFuncDef[1], -- library
                      lFuncDef[2], -- function name
                      lFuncDef[3] -- param signature
                      )
        vw32Routines[funcid] = lFuncDef
        end if

        c_proc(lFuncDef, parms)
    else
        abortErr(Err_BADFUNCID)
    end if
    else
    if funcid > 0 then
        c_proc(funcid, parms)  -- <--ligne 283 of win32lib\Include\w32dll.ew
    else
        abortErr(Err_BADFUNCID)
    end if
    end if


    if memset != 0 then
        w32release_mem(memset)
    end if

end procedure

3. Re: win32lib et multitasking

• Posted by Ryan W. Johnson <ryanj at fluidae.com> Nov 09, 2006
• 966 views

I was under the impression that libraries like win32lib and wxEuphoria would not
work with multitasking, because the winMain() (or equivalent) procedure does not
have a task_yield() statement, and therefore will not give up control of the main
task to the scheduler. I would that that this statement would have to be added
for multitasking to work with these libraries.

For example, a win32lib application main loop is basically something like this:

procedure eventLoop(integer id, atom Flag)
--SNIP--
    -- message loop
    while Flag != 0
      and ActiveEL[el] = 0
      and vWinMainState = kStarted do
        --SNIP--   

        w32Proc( xTranslateMessage, { msg } )
        w32Proc( xDispatchMessage, { msg } )
        Flag -= inc
--ADD THIS STATEMENT HERE:
        task_yield()

    end while
--SNIP--
end procedure

global procedure WinMain( object id, integer style )
    --SNIP--
    -- Start processing the message events.
    eventLoop(0, -1)
    --SNIP--
end procedure

WinMain(winmain, 0)

What I'm saying is, I would think that this main loop in win32lib.ew that
handles the win32 messages would need task_yield() added. (Similar circumstance
in wxEuphoria, too). Am i correct?

~Ryan W. Johnson

Fluid Application Environment
http://www.fluidae.com/

[cool quote here, if i ever think of one...]

5. Re: win32lib et multitasking

• Posted by Jonas Temple <jtemple at yhti.net> Nov 09, 2006
• 989 views

FWIW, I'm working on changes to FROG that will use the new multi-tasking
features.  Here's one way I found to use the multi-tasking within a win32lib
based program.  Note that this has not been thoroughly tested yet...

-- Here was the old function call that would execute an SQL statement
-- on the host.  This is where my program would appear to the user as
-- "not responding"
--          results = ecadb_execute(sql_system, sql_statement, cpp,
--                               describe_option, sql)
-- I replaced it with this call.  "task_sql" is basically the above 
-- function call.
            task_schedule(task_create(routine_id("task_sql"), 
                        {sql_system,sql_statement,cpp,describe_option,sql}),
                        1)
-- How many tasks are running?
            task_l = length(task_list())        
            msg = acquire_mem(0, SIZEOF_MSG)
-- Now I drop into a translate/dispatch message loop to keep the 
-- program responding while I wait for the return results. When the 
-- task count drops to 1 (main task) I drop out of this loop.
            -- Process message loop until end of program
            while w32Func( xGetMessage, { msg, 0, 0, 0 } ) and task_l > 1 do
                w32Proc( xTranslateMessage, { msg } )
                w32Proc( xDispatchMessage, { msg } )
                task_yield()                    
                task_l = length(task_list())                
            end while

Now way down in the bowels of the ecadb_execute function I open the DLL with
Daniel Kluss' TDLL routines:

cwbdb = open_tdll("cwbdb.dll")

Then I defined the C function in cwbdb.dll with his define_t_func:

-- Old approach
--  xcwbDB_Fetch = define_c_func(cwbdb,
--          "cwbDB_Fetch", {C_ULONG, C_ULONG}, C_UINT)
-- New approach
    xcwbDB_Fetch = define_t_func(cwbdb,
            "cwbDB_Fetch", {C_ULONG, C_ULONG}, C_UINT)

Then I call the function using his t_func:

global function cwbDB_Fetch(atom request_handle, atom error_handle)
--  cwbDB_EURtnCode = c_func(xcwbDB_Fetch,
--              {request_handle, error_handle})
    cwbDB_EURtnCode = t_func(xcwbDB_Fetch,
                {request_handle, error_handle})
    return {cwbDB_EURtnCode}
end function

I realized once I had made these changes that I was going to have to rework a
lot of my code to use this approach but frankly it's worth it.  All this to say
that using tasking with e,xisting win32lib GUI programs is not going to be a
trivial matter.  Take the time to analyze what changes your program will need.

Jonas Temple
http://www.yhti.net/~jktemple

7. Re: win32lib et multitasking

• Posted by Chris Bensler <bensler at nt.net> Nov 16, 2006
• 985 views
• Last edited Nov 17, 2006

chadal wrote:
> 
> After différents tests to search more in depth, i've activated the trace
> function
> with the parameter 3. Results of the ex.err and ctrace.out files are below.
> 
> But what is the real statement in error ?
> 
> François Chadal
> 
> 
> What i see in the ex.err file is :
> 
> ---------------------- TASK ID 0 initial task ----------------------------
> D:\EUPHORIA\Biblio\win32lib\Include\Win32Lib.ew:31798 in function fDoTimer()
> 
> A machine-level exception occurred during execution of this statement 
>     id = <no value>
>     hWnd = <no value>
>     iMsg = <no value>
>     wParam = <no value>
>     lParam = <no value>
>     pReturn = <no value>
> 
> here the Euphoria code of the fDoTimer() function of in the win32lib program:
> }}}
<eucode>
> ----------------------------------------------------
> function fDoTimer(integer id, atom hWnd, atom iMsg, atom wParam, atom lParam,
> atom pReturn)
> ----------------------------------------------------
>     VOID = invokeHandler(id, w32HTimer,{wParam} )
>     return {pReturn} <-- ligne 31798 of win32lib.ew
> end function
> </eucode>
{{{

> 
> What i see in ctrace.out file just before the end tag is:
> 
> w32dll.ew:266	    if funcid > kMagicRtnID then                            
>   
> w32dll.ew:267	    funcid -= kMagicRtnID                                    
>  
> w32dll.ew:268	    if funcid <= length(vw32Routines) then                  
>   
> w32dll.ew:269	        lFuncDef = vw32Routines[funcid]                      
>  
> w32dll.ew:271	        if sequence(lFuncDef) then                           
>  
> w32dll.ew:288	        c_proc(lFuncDef, parms)                              
>  
> w32dll.ew:182	    trace_funcid = funcid                                    
>  
> w32dll.ew:183	    trace_parms = parms                                      
>  
> w32dll.ew:185	    memset = 0                                               
>  
> w32dll.ew:186	    for i = 1 to length(parms) do                            
>  
> w32dll.ew:187	        if sequence(parms[i]) then                           
>  
> w32dll.ew:193	    end for                                                  
>  
> w32dll.ew:187	        if sequence(parms[i]) then                           
>  
> w32dll.ew:193	    end for                                                  
>  
> w32dll.ew:187	        if sequence(parms[i]) then                           
>  
> w32dll.ew:193	    end for                                                  
>  
> w32dll.ew:187	        if sequence(parms[i]) then                           
>  
> w32dll.ew:193	    end for                                                  
>  
> w32dll.ew:194	    if funcid > kMagicRtnID then                            
>   
> w32dll.ew:195	    funcid -= kMagicRtnID                                    
>  
> w32dll.ew:196	    if funcid <= length(vw32Routines) then                  
>   
> w32dll.ew:197	        lFuncDef = vw32Routines[funcid]                      
>  
> w32dll.ew:199	        if sequence(lFuncDef) then                           
>  
> w32dll.ew:217	        lRC = c_func(lFuncDef, parms)                        
>  
> w32dll.ew:228	    if memset != 0 then                                      
>  
> w32dll.ew:232	    return lRC                                               
>  
> w32dll.ew:300	trace(0)                                                     
>  
>                                                                            
>  
> === THE END ===

Memory is being corrupted. Try using safe.e to debug memory leaks.

Chris Bensler
~ The difference between ordinary and extraordinary is that little extra ~
http://empire.iwireweb.com - Empire for Euphoria