autoit crashes after the call to the c style dll succeeds

[nss]

Hello everyone,

I'm having a hard time debugging what's wrong with this.

I'm trying to call the c style library called universal speech from autoit 3 (I'm using the latest final release), and after the dll does what I want it to, autoit crashes and displays the message autoit has stopped working... I'm not sure if I'm doing something wrong here?

autoit:

↓

#notrayicon
dllcall("UniversalSpeech.dll", "int", "speechSayA", "str", "test 123", "int", 1)
sleep(1000)

↑

universal speech.h:

↓

#ifndef ____UNIVERSAL_SPEECH_H__
#define ____UNIVERSAL_SPEECH_H__
#if defined __WIN32 || defined __WIN64
#define export __declspec(dllexport)
#else
#error Platform currently unsupported
#endif
#ifdef __cplusplus
extern "C" {
#endif
int export speechSayA (const char* str, int interrupt) ;
#ifdef __cplusplus
} // extern "C"
#endif
#endif

↑

I've successfully did this in other programming languages but autoit doesn't seem to like it; plz help!

[binhnx]

@nss:

The C function is cdecl. 

The default calling convension of AutoIt's DllCall is stdcall.

Either change DllCall convension to cdecl (dllcall("UniversalSpeech.dll", "int:cdecl",...) (easier) or add _stdcall to your C function (you may be messing with the decorated name)

[jdelaney]

Another route:

$oVoice = ObjCreate("SAPI.SpVoice")
$oVoice.Speak ('test 123')

And wow, I haven't used SAPI in a while...it's getting much better.

Edited December 5, 2014 by jdelaney

[nss]

Thanks lots @binhnx.

calling with cdecl fixed it, though it'd be cool if autoit automatically tried to switch to cdecl if the stdcall one doesn't work and not just randomly crash giving anyone who's messing with dll's no idea why that happened since there can be 1 milion possible reasons.

[binhnx]

@nss: Simply, it's technically impossible. You cannot know the function work correctly or not until you actually call the function (and get crash). You can only check if the function is exist (name and number of parameters match), which is already handled with AutoIt

[SmOke_N]

Thanks lots @binhnx.

calling with cdecl fixed it, though it'd be cool if autoit automatically tried to switch to cdecl if the stdcall one doesn't work and not just randomly crash giving anyone who's messing with dll's no idea why that happened since there can be 1 milion possible reasons.

Well, there's an argument to that.  You shouldn't be doing or using something you don't understand?

But more than that, if you're going to be using another libraries API, it's not too difficult to find out if it's written with STDCall or Cdecl, which alternatively narrows down the "1 million" reasons to just 1 .

P.S.

The help file has this information under the very function you were referencing for this post... DllCall

 

By default, AutoIt uses the 'stdcall' calling method. To use the 'cdecl' method place ':cdecl' after the return type.

DllCall("SQLite.dll", "int:cdecl", "sqlite3_open", "str", $sDatabase_Filename , "long*", 0).

Edited December 5, 2014 by SmOke_N