Stuck with sorting macros

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Grom PE

Joined: 13 Mar 2008
Posts: 114
Location: i@grompe.org.ru

Grom PE 30 Mar 2009, 05:45

I'm trying to produce macros that sort everything in between.

So what ideal code should do:
— collect instructions in macros;
— sort these macros according to their order (in my code, this step is merged with the previous one);
— execute these macros in order (stuck here in calling them in a loop).

Code:

format binary as 'txt'

; == Macros ==

macro startcraziness
{
  macro dummymacro \{
}

lastorder = 0

macro sortme order
{
  exist_sorter#order = 1
  if lastorder < order
    lastorder = order
  end if
  macro sorter#order \{
}

macro endcraziness
{
;  repeat lastorder
;    if defined exist_sorter#%
;      sorter#%
;    end if
;  end repeat
  sorter1
  sorter2
  sorter3
  sorter200
  sorter255
  ; == STUCK: how do I replace this with a loop? ==
}

sortme       fix } sortme
endcraziness fix } endcraziness

; == Test program ==

startcraziness

sortme 3
  db 'should '

sortme 255
    db 'in between!'

sortme 1
  db 'These '

sortme 200
     db 'sort everything '

sortme 2
     db 'macros '

endcraziness

; Result should be:
; "These macros should sort everything in between!"

And I guess even if loop there is possible, with very big lastorder it would take much time, so is there any better suggestions?

30 Mar 2009, 05:45

revolution
When all else fails, read the source

Joined: 24 Aug 2004
Posts: 20300
Location: In your JS exploiting you and your system

revolution 30 Mar 2009, 06:10

I think the first to realise with fasm is the separation of the preprocessor-stage and the assembler-stage. Above you have mixed up the two parts so that makes the macros impossible to work like that.

You need to decide beforehand if you want to use the preprocessor-stage for sorting (hard) or the assembler-stage for sorting (easier).

One place to start looking for examples is the export macros in the windows package. It is an assembler-stage based sorter but does not sort strings of unequal length, it sorts the indices only. So you will need to make a few changes to get it to work with variable length strings.

30 Mar 2009, 06:10

Grom PE

Joined: 13 Mar 2008
Posts: 114
Location: i@grompe.org.ru

Grom PE 30 Mar 2009, 06:37

Thanks, revolution, but I don't really see where sorting occurs in export macros. What does it sort exactly?

I have fasm 1.67.27 if it does matter.

30 Mar 2009, 06:37

revolution
When all else fails, read the source

Joined: 24 Aug 2004
Posts: 20300
Location: In your JS exploiting you and your system

revolution 30 Mar 2009, 06:53

This part:

Code:

   common
    local x,y,z,str1,str2,v1,v2
    x = count shr 1
    while x > 0
     y = x
     while y < count
      z = y
      while z-x >= 0
       load v1 dword from names+z*4
       str1=($-RVA $)+v1
       load v2 dword from names+(z-x)*4
       str2=($-RVA $)+v2
       while v1 > 0
    load v1 from str1+%-1
       load v2 from str2+%-1
       if v1 <> v2
    break
      end if
       end while
       if v1<v2
    load v1 dword from names+z*4
        load v2 dword from names+(z-x)*4
    store dword v1 at names+(z-x)*4
     store dword v2 at names+z*4
 load v1 word from ordinal+z*2
       load v2 word from ordinal+(z-x)*2
   store word v1 at ordinal+(z-x)*2
    store word v2 at ordinal+z*2
       else
 break
       end if
       z = z-x
      end while
      y = y+1
     end while
     x = x shr 1
    end while }

It sorts the export names into alphabetical order. But, like I mentioned, only the indices are sorted so if you look at an exe file with a hex editor you might think it is unsorted until you follow the indices and see how it works.

30 Mar 2009, 06:53

Grom PE

Joined: 13 Mar 2008
Posts: 114
Location: i@grompe.org.ru

Grom PE 30 Mar 2009, 07:31

Ah! Now I see.
Now I'm trying to understand how can I use it.

Imagine we have a string sorting macro, how does it help?

I guess we need a list sorting macro...

30 Mar 2009, 07:31

revolution
When all else fails, read the source

Joined: 24 Aug 2004
Posts: 20300
Location: In your JS exploiting you and your system

revolution 30 Mar 2009, 16:42

Here is a very simple preprocessor sorter, but it still requires a manually set maximum loop counter (256 in this case):

Code:

macro sortme level*,text* {
      @sort#level equ text
        @sort#level#flag equ y
}
macro dosort {
     rept 256 level:0 \{
               match =y,@sort\#level\#flag \\{
                    db @sort\#level
            \\}
  \}
}

sortme 3,'should '
sortme 255,'in between!'
sortme 1,'These '
sortme 200,'sort everything '
sortme 2,'macros '

dosort

30 Mar 2009, 16:42

Grom PE

Joined: 13 Mar 2008
Posts: 114
Location: i@grompe.org.ru

Grom PE 30 Mar 2009, 18:21

Thank you, revolution!

I actually wanted to remove a limitation in my patching macros
that "patchat" offsets must be in ascending order,
but trying several times with integrating your sorter, I was able only to complicate the syntax
(i.e. couldn't just remove the limitation without changing the syntax),
so I guess I'll just leave these macros as is, until
— I get more experienced with fasm,
— or somebody suggests a clear syntax solution,
— or Tomasz makes something interesting that allows changing assembling point =)

30 Mar 2009, 18:21

Madis731

Joined: 25 Sep 2003
Posts: 2139
Location: Estonia

Madis731 31 Mar 2009, 10:31

Is this more ... logical?

Code:

macro sortme order*,text* {
        sort#order equ text
}
macro dosort {
        rept 256 order:0 \{
                if defined sort\#order
                        db sort\#order
                end if
        \}
}

sortme 3,'should '
sortme 255,'in between!'
sortme 1,'These '
sortme 200,'sort everything '
sortme 2,'macros '

dosort

31 Mar 2009, 10:31

revolution
When all else fails, read the source

Joined: 24 Aug 2004
Posts: 20300
Location: In your JS exploiting you and your system

revolution 31 Mar 2009, 11:07

Uses the assembler-stage. My posting was preprocessor-stage only.

31 Mar 2009, 11:07

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