More info http://www.clarionmag.com/cmag/faq.html

This is something I hadn’t noticed before today. It may be common knowledge to others

When editing an embed, if you hold down control key then PageUp and PageDown are restricted to the current page instead of scrolling up/down. Kind of like Home/End for the visible area only.

Do you know of any other obscure keyboard tricks in the Clarion editor?

J-Blowfish is a Clarion wrapper (pure Clarion source, no black boxes) for the Blowfish  encryption algorithm. Most of this code was written by Andy Ireland  – we have added a helper class, examples, templates, etc.

I learnt a lot looking into this code a few years ago (wow, it was 2006 looking at my notes!). At the time we needed an implementation of the Blowfish Encryption Algorithm to share encrypted data between a Clarion and Java application. J-Blowfish seemed like a great fit but unfortunately we found that it was not producing standard encrypted data and was also unable to decrypt anything produced by another implementation.

The solution at the time was to use a C DLL instead. This worked fine but seemed a bit ugly, I would have much preferred a pure clarion solution. Also, the code in  jblowfish.clw intrigued me.

NOTE: This is just me poking around in things to learn something new. Don’t blame me if following anything in this blog sinks your submarine or whatever

Here is what I found…

(It is simpler to deal with hex output so that is the only section I have looked at but the results impact all encrypt/decrypt functions.)

1st, Implementation problem:

(In the “Main” procedure of BlowDemo.app)

In the demo supplied with J-Blowfish the local variable holding the key is not clipped. This means the actual key used for the Encryption is inclusive of the trailing spaces in the STRING.

Additionally, the blowfish encryption mode implemented in J-Blowfish (which I believe is ECB) requires your data to be a multiple of 8 bytes. The original implementation will pad an extra 8 bytes if the data is already a multiple of 8.

Original:

RtnEncryptHex  routine
 
  ! Set some properties
  MyBlowfish.Key32 = loc:Key
  MyBlowfish.Size = Len(Clip(loc:Text)) + (8-(Len(Clip(loc:Text))%8))

Suggested improvements:

RtnEncryptHex  routine
 
  ! Set some properties
  MyBlowfish.Key32 = Clip(loc:Key) ! Because loc:Key is a string not cstring without the Clip() your key is including spaces
 
  IF Len(Clip(loc:Text))%8 > 0
    ! Pad the data to the nearest 8 character block
    MyBlowfish.Size = len(clip(loc:Text)) + (8-(len(clip(loc:Text))%8))
  ELSE
    ! If the data length is exactly a multiple of 8 then there is no need to pad another 8.
    MyBlowfish.Size = len(clip(loc:Text))
  END

2nd, Encryption problem (jblowfish.clw)

The “BlowFish._Encrypt” method seems to be the culprit in the encryption errors I experienced.

In my testing I was using this data:

key: “abc”

plain text: “abcdefgh”

encrypted result (other tools): “94c559d64e1251fb”

I discovered that if in the BlowDemo.exe I used this data, “dcbahgfe” I would get the correct result (almost… the result was also backwards “d659c594 fb51124e”)

So it came down to a problem with the way the data was being passed to the “self.BF_Encrypt(pWork, pWork2)” part of this method.

(note: the BF_Encrypt method is used successfully in the BlowFish.Initialise method, I checked the values being generated and they are all correct)

Basically I believe this is because the Endianness of clarion longs is different to whatever assumption is made in the algorithm J-.Blowfish is based upon.

This is what I came up with:

BlowFish._Encrypt procedure(long pData, long dwBytes)
 
nBlocks                 long,auto
i                       long,auto
pWork                   long,auto
pWork2                  long,auto
bchar                   &byte
block                   string(8)
block2                  string(8)
 
  code
    if dwBytes % 8
      return false.
 
    nBlocks = bshift(dwBytes, -3)
    pWork = pData
 
    loop i = 1 to nBlocks
      pWork2 = pWork + 4
 
      ! Reverse the order of the first 4 bytes 
      bchar &= (pWork + 3)
      block[1] = Chr(bchar)
      bchar &= (pWork + 2)
      block[2] = Chr(bchar)
      bchar &= (pWork + 1)
      block[3] = Chr(bchar)
      bchar &= (pWork + 0)
      block[4] = Chr(bchar)
      ! Reverse the order of the next 4 bytes 
      bchar &= (pWork + 7)
      block[5] = Chr(bchar)
      bchar &= (pWork + 6)
      block[6] = Chr(bchar)
      bchar &= (pWork + 5)
      block[7] = Chr(bchar)
      bchar &= (pWork + 4)
      block[8] = Chr(bchar)
 
      !self.BF_Encrypt(pWork, pWork2) ! <-- doesnt work
      self.BF_Encrypt(Address(block), Address(block)+4)
 
      ! Now swap them back again
      block2[1] = block[4]
      block2[2] = block[3]
      block2[3] = block[2]
      block2[4] = block[1]
      block2[5] = block[8]
      block2[6] = block[7]
      block2[7] = block[6]
      block2[8] = block[5]
      ! And replace the data in "BinData" with the encrypted values
      Poke(pWork, block2)
 
      pWork += 8
    end
    return true

Other considerations:

• This only takes care of the Encryption phase something similar will need to happen in the Decrypt method.
• There may be better ways (band, bshift, bxor, whatever) to do this but it was late and this way is at least descriptive
• I passed a few of the standard test vectors through the changed version and it seems to work correctly now. Most implementations have in them somewhere a self test method that uses these test vectors to prove they are running correctly:

  http://www.schneier.com/blowfish.html

  http://www.schneier.com/code/vectors.txt

• One thing I learned (amongst many!) whilst doing all this. It seems you can safely do a search replace in jpwbfish.inc and jpwbfish.clw to replace all ULONG’s with LONG’s. This may even result in some speed improvements as supposedly longs are faster then ulongs. Reason for this is that longs are 32 bit and that is sufficient for blowfish as it works in 32 bit words. It seemed weired to me at first, its like when you do this:

SomeProcedure PROCEDURE()
x LONG
  CODE
 
  x = 2147483647 ! The highest value a long can take
  Message(x) ! It will show "2147483647"
  x += 1
  Message(x) ! It will show "-2,147,483,648"

But blowfish doesn’t care about the +/- part as it is working directly on the bytes in the long, thus a LONG is sufficient.

(This explanation may be off on a few technical points but you get the drift?)

I hope all the above makes (some) sense!

-brahn

Clarion IDE Fonts & save your eyes ? 17/12/2005 3:44:38 PM

I found that by careful tweaking of the registry values it was possible to alter the fonts used by the Clarion IDE!

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows NT\CurrentVersion\FontSubstitutes

It’s not quite as straight forward as simply specifying the fonts you want as it seems that not all fonts will be accepted. I have no idea if this is the Clarion IDE or the windows font substitutions fault but I think it is best to take what you can get at this point!

Important Note:
It is required to restart Windows to allow a new or changed font substitution to take effect.

First, lets go straight to the before and after pictures:

And now for a little more detail on just how this works…

For demonstration purposed I have used Segeo Script in all these examples. You will have to play with it and work out what suits your tastes best.

The After pictures employes these techniques:

• Font substitution to change the IDE fonts
• CWPlus with custom ClarionEdge icon set!
• Custom background specified in the C60PE.ini/C60EE.ini file. (I think the one I am using here cam from 1stLogoDesign at some point)

There are three main registry string that we are going to play with:

1. MS Shell Dlg
2. Helv
3. MS Sans Serif

The last one, MS Sans Serif, is a new registry string that you will have to add to make this work.

Helv

This one covers most of the IDE – procedure Tree, template dialogs, etc

New String: MS Sans Serif

File picker, All the other IDE property boxes such as the Populate column toolbox and things like the main IDE Tabs.

Finally: MS Shell Dlg

This one will change all window dialogs, you will notice it a lot more in other places than just the ClarionIDE

e.g.

Not hard but nice to have.

Thanks Mark for the assistance!

Some examples:

1. 05-Oct-2009 + 1 Month = 05-Nov-2009
2. 31-Oct-2990 + 1 Month = 30-Nov-2009

AddMonths PROCEDURE  (LONG pDate, BYTE pMonths) !,LONG
originalDay BYTE
returnDate  LONG
  CODE
  originalDay = Day(pDate)
 
  returnDate = Date(Month(pDate) + pMonths, Day(pDate), Year(pDate))
 
  IF Day(returnDate) <> originalDay
    returnDate = Date(Month(returnDate), 1,  Year(returnDate)) - 1
  END
 
  RETURN returnDate

The magic line to add to your addin file is this:

<StringResources file="Resources\StringResources.resources">

Then for each language you intend to support you create a new resource file with the correct name e.g. StringResources.nl.resources for dutch.

In the download you will find the C# project files as well as the addin itself. Also included is a BitmapResources.resources file containing all the Silk icons from famfamfam which I thought were pretty neat to use as menu icons

Download:	AccessoryMenu.sdaddin
Version:	0.1
Updated:	June 2, 2009
Size:	618.58 KB
Downloads:	122

Download:	AccessoryMenu.zip
Version:	0.1
Updated:	June 2, 2009
Size:	1.82 MB
Downloads:	107

This is the addin file in case you want a quick look:

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<AddIn name        = "AccessoryMenu"
       author      = ""
       url         = ""
       description = "Common menu for all addin writers!">
 
	<Manifest>
		<Identity name="AccessoryMenu.Addin" version="0.3"/>
		<Dependency addin = "SharpDevelop" version = "2.1"/>
	</Manifest>
 
	<BitmapResources file="Resources\BitmapResources.resources"/>
	<StringResources file="Resources\StringResources.resources"/>
 
	<Path name = "/SharpDevelop/Workbench/MainMenu/Help">
		<MenuItem id = "Accessory" 
		          label = "${res:Addin.Menu.Accessory}" 
		          type ="Menu" 
		          insertbefore = "SDKHelp">
			<MenuItem id = "About"
					  label = "${res:Addin.Menu.About}"
					  icon = "Icons.Silk.plugin"
					  link = "http://www.c3pa.com/"/>
		</MenuItem>
	</Path>
 
</AddIn>

1. Download the addin file – Clarion3rdParty.sdaddin
2. Start the Clarion 7 IDE:
   
3. Go to the Tools menu and select the Addin Manager:
   
4. Click the Install Addin button:
   
5. Find the Addin file you downloaded in Step 1
   
6. You should now see the new addin listed in the Addin Manager, restart the IDE to see what it does!
   
7. And there you have it, a new menu item under Help–>Web !
   

Simply adding a menu item is very easy with the new Clarion 7 IDE. I suppose the hardest part is finding the correct names for everything and getting them in the right place. The Clarion3rdParty.sdaddin file you downloaded at the beginning is just a zip file containing one XML formatted “addin” file. This XML simply tells the IDE what you want to do and where to do it.

This is the XML used in the Clarion3rdParty addin:

<AddIn name    = "Clarion3rdPartyAddin"
   author      = "Brahn Partridge"
   url         = ""
   copyright   = ""
   description = "TODO: Put description here">
 
	<Manifest>
		<Identity name="ClarionEdge.Clarion3rdPartyAddin" version="0.1"/>
		<Dependency addin = "SharpDevelop" version = "2.1"/>
	</Manifest>
 
	<Path name = "/SharpDevelop/Workbench/MainMenu/Help/Web">
		<MenuItem id = "Clarion3rdParty" label = "Clarion 3rd Party" type="Menu">
			<MenuItem id = "ClarionEdge"
					  label = "www.clarionedge.com"
					  icon = "Icons.16x16.WebSearchIcon"
					  link = "http://www.clarionedge.com/"/>
		</MenuItem>
 
	</Path>
</AddIn>

And the download again in case you missed it:

Download:	Clarion3rdParty.sdaddin
Version:	0.1
Updated:	May 20, 2009
Size:	471 bytes
Downloads:	197

Just yestarday I managed to duplicate these symptoms in my development environment and discovered that the problem was being triggered in the InitSetEventOffset ROUTINE of the Debuger class we are using.

You can download the class over at Radfusion Free Downloads.

The helpful folk over at the clarion skype chat were able to narrow this down to a problem with the length of the CSTRING used in the call to DebugerNameMessage.

Further analysis shows that this only manifests as an issue under very specific circumstances:

• The class instance is created using New().
• The application is compiled with debug mode set to “off” (or in other words, in “release” mode).
• The application is run “asInvoker” on a system with UAC tuned ON.
• There is no “EventOffset” entry already in the WIN.INI file*.

_{* That last point will depend on the version of the debuger class you are using. The one we have here is “6.0.2″ but there are others around that no longer use WIN.INI and they might work OK. Note though that when I say “OK” the problem hasn’t gone away and you will still see the APPCRASH error the first time your program is run but subsequent executions will be able to read the offset from the INI file and this bypasses this bug.}

Changing the variable from CSTRING(20) to CSTRING(128) fixed the problem (Thanks Larry!) but I was still curious to find out what the cause was.

First lets look at the prototype forDebugerNameMessage :

MODULE('C%V%RUN%X%')
  DebugerNameMessage(*CSTRING, UNSIGNED EventNum ),NAME('WslDebug$NameMessage'),RAW   !Note: use   EVENT() + EVENT:FIRST else will get WM_*
END

And it’s usage:

Debuger.GetEventDescr             PROCEDURE(LONG ArgEvent)
LOC:Retval   CSTRING(20)
LOC:EventNum UNSIGNED
  CODE
  DebugerNameMessage(LOC:Retval, LOC:EventNum)

(I have removed all the other code from the above method just for clarity in this example)

The call to DebugerNameMessage crashed just after giving this result:

LOC:Retval=WM_OTHERWINDOWCREATE, LOC:EventNum=66

When the LOC:RetVal is changed to CSTRING(128) we see that the next call is this:

LOC:Retval=WM_OTHERWINDOWDESTROY, LOC:EventNum=67

The reason for the crash I guess is Len(WM_OTHERWINDOWDESTROY) > 20

There are 2 questions remaining and I think I have the answer for one:

Why does it only crash when the class is instantiated with New()?

I am pretty sure this simply because when using New() the “EventOffset” is different and so the InitSetEventOffset routine attempts to find the correct offset and thus triggering the problem with our too small variable.

Why does it only happen when the program is compile with debugging turned OFF?

I guess in debug mode the code it is not so sensitive about the buffer overrun it still seems kind of strange that it should work at all.

Hopefully someone reading this will be able to give a hint as to a possible reason?

To use the Mozilla example you will need to download and install the Mozilla ActiveX Control from here:

http://www.iol.ie/~locka/mozilla/control.htm#download

Enjoy!

Download:	EmbMozilla.app
Version:	0.1
Updated:	March 16, 2009
Size:	48.25 KB
Downloads:	168
Details:	Clarion App file created with Clarion 6.3

Download:	EmbMozilla.exe
Version:	0.1
Updated:	March 16, 2009
Size:	1.03 MB
Downloads:	146
Details:	Executable compiled with Clarion 6.3. in local mode so it should run as is. (Don’t forget to install the mozilla OCX!)

The Problem: One of our stored procedures was using CHARINDEX to search for strings within the database. The problem appeared when a user defined a search parameter containing a trailing space and the results of the search were not as expected.

SQL and Trailing Blanks

(From the section “Comparison operators, listed” in SQL help)

Trailing blanks are ignored in comparisons; for example, these are equivalent:

WHERE LastName = 'White'
WHERE LastName = 'White '
WHERE LastName = 'White' + SPACE(1)

This is an interesting article: INF: How SQL Server Compares Strings with Trailing Spaces

Sort of related but actually about how data is stored is the ANSI_PADDING setting:

http://technet.microsoft.com/en-us/library/ms187403.aspx

Display Trailing Space in Clarion

The Clarion entry control and text control don’t appear to be able to show trailing spaces from data in a database. You can enter trailing spaces in an entry or text control and save the data but next time you view or edit the form those trailing spaces are not shown.

Funnily enough, if the data does have trailing spaces and the field is not edited then the trailing spaces remain intact when the form is saved.

Fun with SELECT Statements

Have a play with the following SQL to see some examples:

Note the use of “LIKE” rather than “=” and the “[^ ]” will force the WHERE to only match items without the trailing space.
Also, try setting the ANSI_PADDING to “OFF” and see the difference in the results.

SET ANSI_PADDING ON;
CREATE TABLE t1 (charcol CHAR(16) NULL, varcharcol VARCHAR(16) NULL)
INSERT INTO t1 VALUES ('No blanks', 'No blanks');
INSERT INTO t1 VALUES ('Trailing blank ', 'Trailing blank ');
 
SELECT * FROM t1 WHERE varcharcol LIKE 'No blanks     '
SELECT * FROM t1 WHERE charcol LIKE 'No blanks     '
 
SELECT * FROM t1 WHERE varcharcol LIKE 'Trailing blank[^ ]'
SELECT * FROM t1 WHERE charcol LIKE 'Trailing blank[^ ]'
 
DROP TABLE t1

So there are a few thoughts and discoveries that came up in the course of investigating this issue. Of course once you know the reasons there are ways to workaround the problems but I will leave that up to your individual scenario…