OpenEuphoria

2. Re: ver 4.0 call_back question ?

• Posted by jeremy (admin) Jun 30, 2009
• 1070 views

call_back is to pass routine_id's of euphoria source to C DLL's, apps. routine_id has many uses far beyond call_backs, far beyond forward referencing as well. i.e.

procedure log_to_file(sequence message) 
    -- do something 
end procedure 
 
procedure log_to_stderr(sequence message) 
    -- do something 
end procedure 
 
procedure log_to_database(sequence message) 
    -- do something 
end procedure 
 
procedure log_to_tcpip(sequence message) 
    -- do something 
end procedure 
 
procedure log(sequence message) 
    call_proc(log_rid, { message }) 
end procedure 
 
integer log_rid = routine_id("log_to_stderr") 
 
log("Hello") 
log("Goodbye") 

i.e. dynamic programming. As for callback's in DOS, the conventional purpose for call backs, being DLLs, doesn't work in DOS. I don't know about ASM based code, I'm an ASM dummy.

Jeremy

4. Re: ver 4.0 call_back question ?

• Posted by bernie Jun 30, 2009
• 1018 views

I know what routine_id is used for.
I want to be able to use call_back in DOS
just the same as when using euiw.exe

-- This works with euiw.exe I want it to work with euid.exe 
-- excerpt from my assembler code 
"push eax "& 
"mov eax, &sprintf("%d ",{call_back(routine_id("some_eu_function"))& 
"call near eax "&    
-- etc. 

6. Re: ver 4.0 call_back question ?

• Posted by bernie Jun 30, 2009
• 1055 views

Jim: I just tried to build SVN2191 but it crashs during DOS build.

Thanks for trying

It looks like it is more involved than just changing the back end.

8. Re: ver 4.0 call_back question ?

• Posted by bernie Jun 30, 2009
• 1074 views

Derek: svn 2192 builds ok now; but using DOS call_back crashes with
causeway error.

CauseWay DOS Extender v3.45 Copyright 1992-99 Michael Devore. 
All rights reserved. 
 
Exception: 0E, Error code: 0006 
 
EAX=84C65910 EBX=84C85A10 ECX=84C65920 EDX=02000004 ESI=85188F88 
EDI=85188F88 EBP=84003A20 ESP=84C85A18 EIP=84C7F02E EFL=00010202 
 
CS=018F-7B507000 DS=0197-7B507000 ES=0197-7B507000 
FS=0000-xxxxxxxx GS=019F-xxxxxxxx SS=0197-7B507000 
 
CR0=00000000 CR2=00000000 CR3=00000000 TR=0000 
 
Info flags=00008018 
 
Writing CW.ERR file.... 
 
CauseWay error 09 : Unrecoverable exception. Program terminated. 

10. Re: ver 4.0 call_back question ?

• Posted by bernie Jul 01, 2009
• 1047 views

Hi Derek. Sorry for the delay in replying to you but we are in different time zones.

It would be very difficult to send you an example of my code
without sending you my complete library which is far from finished.

What happens is when I run a windows program my library dynamically
compiles assembler routines that are written in both assembler
and Euphoria. These routines run and call other routines using
call_backs to do some parsing.

This works fine in windows.

If I run a DOS program the same library code is executed but
because DOS interpreter will not provide a good call_back the
crashed occurs.

The DOS program does not use call_backs but the library that it is using does.

I guess I can just forget about DOS call_backs and work around it with conditional code.

I hope that call_backs work in Linux because I am hoping
to use assembler there.

This is a sample of what the library code looks like:

export function strlen(atom str) -- tested 
Asm("strlen_", 
"prolog4eu "& 
"cld "& 
"mov edi, [ebp+8] "& 
"xor eax, eax "& 
"or ecx, -1 "& 
"repne scasb "& 
"not ecx "& 
"dec ecx "& 
"mov eax, ecx "& 
"epilog4eu "& 
"ret 0 ",1,u) 
return f("strlen_",{str}) 
end function 
-- 
export function strspn(atom str1, atom str2) -- tested 
Asm("strspn_", 
"prolog4eu "& 
"cld "& 
"xor eax, eax "& 
"mov ecx, [ebp+8] "& 
"jmp ssp004 "& 
"ssp001: "& 
"inc ecx "& 
"mov edi, [ebp+12] "& 
"ssp002: "& 
"mov dh, [edi] "& 
"or dh, dh "& 
"jz ssp005 "& 
"cmp dl, dh "& 
"je ssp003 "& 
"inc edi "& 
"jmp ssp002 "& 
"ssp003: "& 
"inc eax "& 
"ssp004: "& 
"mov dl, [ecx] "& 
"or dl, dl "& 
"jnz ssp001 "& 
"ssp005: "& 
"epilog4eu "& 
"ret 0 ",2,u) 
return f("strspn_",{str1,str2}) 
end function 
-- 
export function strpbrk(atom str1, atom str2) -- tested 
Asm("strpbrk_", 
"prolog4eu "& 
"cld "& 
"mov eax, [ebp+8] "& 
"jmp sb004 "& 
"sb001: "& 
"mov ecx, [ebp+12] "& 
"sb002: "& 
"mov dh, [ecx] "& 
"or dh, dh "& 
"jz sb003 "& 
"cmp dl, dh "& 
"je sb005 "& 
"inc ecx "& 
"jmp sb002 "& 
"sb003: "& 
"inc eax "& 
"sb004: "& 
"mov dl, [eax] "& 
"or dl, dl "& 
"jnz sb001 "& 
"xor eax, eax "& 
"sb005: "& 
"epilog4eu "& 
"ret 0 ",2,u) 
return f("strpbrk_",{str1,str2}) 
end function 
-- 
export function strtok(atom buff, atom delim) -- tested 
Asm("strtok_", 
"prolog4eu         "& --  -- 
"mov esi, [ebp+8]  "& --  get buffer 
"test esi esi      "& --  first call ? 
"jz nexttok        "& --  no 
"mov [@ptr], esi   "& --  save buffer 
"nexttok:          "& -- 
"mov edi, [ebp+12] "& --  yes get delimit 
"mov esi, [@ptr]   "& --  get current ptr 
"cmp esi, 0        "& -- 
"je near endtok    "& --  bail out 
"push edi          "& --  delimit 
"push esi          "& --  buffer 
"mov eax, "&AGet("strspn")& -- << ---- <<  THIS IS A CALL BACK 
"call near eax "& --  find start of token 
"add [@ptr], eax   "& --  goto first token 
"mov edi, [ebp+12] "& --  get delimit 
"mov esi, [@ptr]   "& --  get current ptr 
"cmp esi, 0        "& -- 
"je near endtok    "& --  bail out 
"cmp [esi], 0      "& --  pointing to zero ? 
"je near endtok    "& --  bail out 
"push edi          "& --  delimit 
"push esi          "& --  buffer 
"mov eax, "&AGet("strpbrk")& -- << ---- <<  THIS IS A CALL BACK 
"call near eax     "& --  find the end of the token 
"mov esi, [@ptr]   "& --  get current ptr 
"cmp eax, esi      "& -- 
"je near endtok    "& -- 
"cmp eax, 0        "& -- 
"je exact          "& -- 
"mov [@ptr], eax   "& -- 
"mov edi, eax      "& -- 
"mov eax, 0        "& -- 
"mov [edi], al     "& -- 
"mov eax, esi      "& -- 
"add [@ptr], 1     "& -- 
"epilog4eu         "& -- 
"ret 0             "& -- 
"exact:            "& -- 
"mov esi, [@ptr]   "& --  get current ptr 
"push esi          "& -- 
"mov eax, "&AGet("strlen")& -- << ---- <<  THIS IS A CALL BACK 
"call near eax     "& -- 
"cmp eax, 0        "& -- 
"jne lasttok       "& -- 
"jmp endtok        "& -- 
"lasttok:          "& -- 
"mov ecx, 0        "& -- 
"mov eax, [@ptr]   "& --  get current ptr 
"mov [@ptr], ecx   "& --  block next call 
"epilog4eu         "& -- 
"ret 0             "& -- 
"endtok:           "& -- 
"mov eax, 0        "& -- 
"epilog4eu         "& -- 
"ret 0             "& -- 
"ptr: dd 0 ",2,u) 
return f("strtok_",{buff,delim}) 
end function