Finding unique ID for each caller to a procedure

RichardL · **Posted:** Thu May 10, 2012 4:01 pm

Is there a way for a procedure called from many places in a program to determine a unique signature for each caller (without passing some form of ID in the call to the procedure)?

If this was a program written in assembler I could inspect the return address on the stack and use that. Is there a way of doing something similar in PB (Microsoft only) ?

I want to re-instate various parameters (Eg: A the position of a window opened by the procedure) to match the parameters established the last time it was called.

STARGÅTE · **Posted:** Thu May 10, 2012 4:17 pm

i don't know if it right, but this code looks good:

Code:

Procedure Test(Parameter.i)
   Protected Address.i
   ! MOV eax, [esp+4]
   ! MOV [p.v_Address], eax
   Debug "Call from: "+Str(Address)
EndProcedure


Test(0)
For n = 1 To 3
   Test(n)
Next
a=b
Test(7)

Thorium · **Joined:** Sat Aug 15, 2009 6:59 pm **Posts:** 1024

STARGÅTE wrote:

i don't know if it right, but this code looks good:

Code:

Procedure Test(Parameter.i)
   Protected Address.i
   ! MOV eax, [esp+4]
   ! MOV [p.v_Address], eax
   Debug "Call from: "+Str(Address)
EndProcedure


Test(0)
For n = 1 To 3
   Test(n)
Next
a=b
Test(7)

Yes, just use the return address as ID.

RichardL · **Posted:** Mon May 14, 2012 11:29 am

Gentlemen,

Thanks for your suggestions. My experience with assembler level coding on Intel processor is a very small fraction of zero! Despite writing all manner of stuff on 65xx processors, including assemblers, I have never dabbled with the equivalent on PCs. Would you kindly suggest the reason why I get the following message when I try to compile the above code:

MOV [P.v_address],Eax
error: undefined symbol 'P.v_address'

Thank you
Richard

gnozal · **Posted:** Mon May 14, 2012 12:50 pm

I think it's a case issue.

It should be p.v_Address and not P.v_address.

rsts · **Posted:** Mon May 14, 2012 1:22 pm

Something like this?

http://www.purebasic.fr/english/viewtopic.php?p=238692

RichardL · **Posted:** Mon May 14, 2012 4:10 pm

Thanks gnozal...
Absolutely right.
It now works and I have the key feature needed to go forward with.

I note that the original post from Stargate had a lower case 'p', and when I copy and paste into jaPBe it changed to an upper case 'P'.

Two other source files were open in the editor and one used 'P' as a variable... and the editor thought it was doing me a favour!
Could this be a possible tweak for jaPBe to not modify the case of variables in an assembler source section?

Richard

gnozal · **Posted:** Tue May 15, 2012 8:13 am

RichardL wrote:

...Could this be a possible tweak for jaPBe to not modify the case of variables in an assembler source section?

I have uploaded a new jaPBe build.
It should not change the case of a variable immediately following an ASM keyword (note : for the ASM keyword to be recognized by jaPBe, it must follow the '!' without any space [!MOV = Ok, ! MOV = not Ok]).

RichardL · **Posted:** Tue May 15, 2012 10:17 am

Good morning,

@gnozal... thanks for the jaPBe update. The best just gets better!

However... I have found a problem / done something stupid.

Code:

Procedure Test(z)
  Protected Address.i
  ! MOV Eax, [Esp+4]
  ! MOV [p.v_Address], Eax
  Debug "Call from: "+Str(Address)
EndProcedure

Procedure Test2(z$)
  Protected Address.i
  ! MOV Eax, [Esp+4]
  ! MOV [p.v_Address], Eax
  Debug "Call from: "+Str(Address)
EndProcedure

Test(1)

For n = 1 To 3
  Test(2)
  Test(3)
Next
a=B
Test(4)

Debug ""

p$ = "hello"
Test2(p$)
For n = 1 To 3
  Test2(p$)
  Test2(p$)
Next
a=B
Test2(p$)

On my machine (Windoze7) Test2 reports each Address as zero.

gnozal · **Posted:** Tue May 15, 2012 10:37 am

RichardL wrote:

On my machine (Windoze7) Test2 reports each Address as zero.

It' because of the string parameter.

Code:

Procedure Test2(z$)
  Protected Address.i
  !MOV Eax, [Esp+8]
  !MOV [p.v_Address], Eax
  Debug "Call from: "+Str(Address)
EndProcedure

RichardL · **Posted:** Tue May 15, 2012 10:54 am

Hi gnozal,

I was rather hoping that this was a simple way to determine some form of caller ID, but it looks like I'm treading on dangerous ground, so maybe it is better to put this problem aside until I can find the time to find out what is really going on.

Thanks for your assistance.

Richard

wilbert · **Posted:** Tue May 15, 2012 11:14 am

You could pass an ID yourself for a procedure that needs one

Code:

Procedure myFn(callerID.i, arg.s)
  Debug "Call from: " + Str(callerID)
  Debug "arg:" + arg
  Debug ""
EndProcedure

Procedure Caller1()
  myFn(@Caller1(), "argument from caller 1")
EndProcedure

Procedure Caller2()
  myFn(@Caller2(), "argument from caller 2")
EndProcedure

Caller1()
Caller2()

RichardL · **Posted:** Tue May 15, 2012 11:28 am

Hi Wilbert,
Yes, I know, but please see line one of my first post... I'm trying to assign an identify to a caller of a Procedure() without the caller sending me an explicit ID.

The reason for this is that I'm producing a complex requester that is called from many places in a large program and I want to reset the position of the requester, and some option items in it, to match the last time it was called from each place. This way the user does not need to re-position the requester etc each time it is used.

Also, I'm most likely going to use the requester in other applications and I would like to solve the problem just the once and from then on I can forget about ID's etc.

Richard

culita · **Joined:** Thu May 03, 2012 1:24 pm **Posts:** 29

maybe will work this(i haven't the possibility to check if work)

Code:

 Macro MYcallID
   Protected Address.i
   ! MOV eax, [esp+4]
   ! MOV [p.v_Address], eax
   Debug "Call from: "+Str(Address)   
 EndMacro



 Procedure Test(Parameter.i)
   MYcallID
 EndProcedure

Procedure Test2(Parameter$)
   MYcallID
 EndProcedure


Test(1)

For n = 1 To 3
  Test(2)
  Test(3)
Next
a=B
Test(4)

Debug ""

p$ = "hello"
Test2(p$)
For n = 1 To 3
  Test2(p$)
  Test2(p$)
Next
a=B
Test2(p$)

i done only one modification on your script

wilbert · **Posted:** Tue May 15, 2012 11:51 am

RichardL wrote:

please see line one of my first post...

Sorry, I overlooked that :oops:

PureBasic Forum

Finding unique ID for each caller to a procedure

Who is online