How do I repair a corrupt memo file?? 1

[acorbally]

I am trying to figure out how to repair a corrupt memo file. I am using my developer's guide but get stuck halfway through. I really need to get this fixed. I even started documenting it when I have fixed it in the past with help with an old co-worker, but now they are gone and I can't remember it all. I only have a third of the documentation I need. HELP!!!

Thanks in advance.

 

[TheRambler]

Hi,

See thread182-548223

 

[acorbally]

I have tried that thread. The first link ends with object not found error and the second link on that thread works fine, but I downloaded a "fix" program and when I copied the corrupt memo file to test the program it blew every memo away. Nice fix. Anyway. I have fixed these before using UltraEdit and shifting bits in Hex, but I am having trouble finding the link between the dbf and the fpt. I know it it an address location in the dbf that points to the memo block position in the fpt but I don't remember the exact steps. Please help.

 

[TheRambler]

Sorry for any inconveniences.
I was able to fix some tables using those programs before.
I have not done what you are trying to do, but maybe this faq can help you:

How to read a DBF Header and get info about it
faq182-3161

If not, just be patient, I am sure somebody else will help you.

 

[rob444]

aanewlon:

Make sure you have a backup of the damaged files first!!!

Then try what I've found on

http://www.prolib.de

Rob.


*****************************************************************************
* FIXDBFLT.PRG (FIXDBF Lite) v1.00, July 1995
* by Lowell Fishman © Copyright 1995
* All Rights Reserved
* DESCRIPTION:
*
* FIXDBFLT repairs damaged FoxPro dbf headers unless extreme damage
* has destroyed vital information.
*
* Associated fpt (memo file) FIXDBF will be correctly repaired too, unlike
* FILEFIX, which is reported to destroy FoxPro memo files. As implemented,
* FIXDBFLT should only be used on FoxPro (not dBase or FoxBase) dbfs. It
* should be trivial to modify the code for these other Xbase implementations,
* if needed. However, I have no plans to do so, so it's up to you. Before
* doing a repair, FIXDBFLT asks first, and if you want to proceed it backs up
* the damaged file with its extension reversed. (.DBF ==> .FBD, .FPT ==> .TPF)
*
* FIXDBFLT was developed under FoxPro 2.5 Mac, but should operate equally
* well on other platforms, as it has no platform-specific code that I am
* aware of. It works well under FoxPro 2.6 Windows, but I have not tried
* it on any other versions or platforms.
*
* HOW TO USE FIXDBFLT:
*
* To use, just issue DO FIXDBFLT. A file selection dialogue will be presented
* repeatedly. Locate the dbf you wish to repair and click 'OK'.
* When you have no more dbfs to fix, click 'Cancel'. That's all there
* is to it. If the fpt memo blocksize appears to be in error, you will be asked
* to enter the value to use. The FoxPro default is 64. Your installation
* convention may be different. Also, different fpts may have different
* blocksizes, so you have to know what's what here. If you have no reason
* to assume otherwise, accept the suggested value of 64. The enhanced version,
* FIXDBF, which comes with the DICT4FP package, bypasses this step as long
* as the dbf is in the DICT4FP database dictionary.
*
* FIXDBFLT is SHAREWARE, it is *not* free. If you find it useful, please send
* the $10 (Ten dollar) shareware fee (a bargain!) to me at the address below.
* Please help support the shareware system (and me too!) by *actually sending
* it*, not just thinking about it!
*
* If you find FIXDBFLT useful, might I suggest that you consider
* purchasing the DICT4FP package (which I offer for sale at $25 to registered
* users of FIXDBLT, $35 otherwise). DICT4FP (Dictionary for FoxPro), not being
* shareware, is available by mail-order only. Once your check is received, I
* will be glad to send either a 3 1/2" diskette (state Mac or DOS format) or
* email you the source, if you prefer.
*
* DICT4FP maintains and prints a complete site database and index dictionary,
* prints the dictionary for documentation purposes, recreates damaged indexes,
* database headers and/or structures, or memo file (fpt) headers but not, of
* course, data. It permits automatic dictionary updating to be performed. It
* may be used either as a 'stand-alone' program or called as a subroutine.
* This is useful in building initialization routines. It can also scan all dbfs
* in the dictionary and automatically determine which indexes are out-of-date
* or in need of repair, and update or repair them. DICT4FP uses the full-
* featured version of FIXDBF which automatically rebuilds dbf and fpt headers
* from dictionary information if they would otherwise be beyond repair.
*
* Also, please remember that I am available for FoxPro design and
* development consulting. (Information on how to reach me is below.)
*
*
* TERMS AND CONDITIONS:
*
*
* 1) FIXDBF is shareware. If you keep it for more than thirty (30) days, you
* owe me ten bucks ($10.00, U.S.currency). More lavish voluntary donations
* to the author will not, however, be refused. Checks drawn on U.S. banks only,
* please. Foreign purchasers please send U.S. currency.
*
* 2) FIXDBF is © copyright 1995 by Lowell Fishman. All rights reserved.
* You may use FIXDBF on your own personal or business computer.
* You may freely distribute unmodified copies of this program, with all
* comments (including this legalese section) but you may not charge money for
* it or include it as part of any sale of, promotion for, or offering of,
* any product or service for which money is charged, other than as a normal
* inclusion in the shareware libraries of online services.
*
* You may modify this program for your own use, but you may not distribute
* such modified copies. Any other use of this program including, but not
* limited to commercial duplication and distribution is expressly forbidden.
* Inquiries from commercial distributors of shareware, such as publishers
* of CD-ROMS or floppy-disk shareware collections, regarding licenses, are
* not only invited, but devoutly hoped for.
*
* 3) You agree to use FIXDBF entirely at your own risk. The author is not
* liable for any damages, direct or consequential, resulting from any use
* of this program, or for any errors it may contain.
*
* 4) Please feel free to report any problems with this program to the author.
* I will probably attempt to remedy them. However, this program comes with
* absolutely no warranty, or guarantee of support of any kind.
*
* 5) The author may be reached by email or by telephone, fax, or snail mail at:
*
* Lowell Fishman
* 69 Bayview Avenue
* Portsmouth, RI 02871
* Tel: (401) 683-6288
* Fax: (401) 683-0368
* Email: <pinpal@aol.com>
*
*****************************************************************************

set echo off
home = sys(5) + curdir() && get the directory we're operating from

* save the environment for when we're done
vfn = sys(3)
create view (home + vfn +'.VUE')
set talk off
clear
close all
close data

* Loop as long as the user has a dbf to fix
do while .T.
close all && in case something is open from last loop

* get file name and path information
longname = getfile('DBF','Find the dbf to be repaired')
if empty(longname)
exit
endif
thePath = left(longname, rat('\',longname))
dbname = right(longname, len(longname) - rat('\', longname))
fptname = left(dbname, rat('.', dbname)) + 'fpt'
set default to (thePath)

* Is there an .fpt file?
hasfpt = file(fptname) && .t. if it has a memo file


* get file header and extract existing info
dbhandle = fopen(dbname, 12) && unbuffered is slower but safer
if ferror() # 0
wait window timeout 5 &quot;Can't open dbf! Repair not made!&quot;
loop
else
wait window nowait &quot;Analyzing dbf . . .&quot;
endif

fsize = fseek(dbhandle,0,2) && get file size
= fseek(dbhandle,0,0) && point to beginning
hdr = fread(dbhandle,32) && get header
if ferror() # 0
wait window timeout 5 &quot;Can't read dbf! Repair not made!&quot;
loop
endif

xhdrtype = left(hdr,1) &&existing header type flag
memotype = .F. && assume no memo fields until proven otherwise

* If you opt to repair a non-FoxPro dbf, it will end up looking like
* a FoxPro dbf

do case
case xhdrtype = chr(3) && x'03'
memotype = .F.
case xhdrtype = chr(245) && x'F5'
memotype = .T.
case xhdtype = chr(131) && x'83'
if !attention(&quot;Just Checking . . .&quot;, ;
&quot;This may be a FoxBase+ or dBaseIII Plus dbf with memo file.&quot; ;
+ chr(13) + &quot;Fix it anyway?&quot
loop
endif
case xhdrtype = chr(139) && x'8B'
if !attention(&quot;Just Checking . . .&quot;, ;
&quot;This may be a dBaseIV dbf with memo file.&quot; ;
+ chr(13) + &quot;Fix it anyway?&quot
loop
endif
endcase

xpof = unintel(substr(hdr, 9, 2)) && where the hdr delimiter should be
xnrecs = unintel(substr(hdr, 5,4)) && what the number of records should be
xldata = unintel(substr(hdr, 11, 2)) && what the record length should be

* convert date from header
tdte = right('0' + alltrim(str(unintel(substr(hdr, 3, 1)))),2) + '/' ;
+ right('0' + alltrim(str(unintel(substr(hdr, 4, 1)))),2) + '/' ;
+ right('0' + alltrim(str(unintel(substr(hdr, 2, 1)))),2)

* test if it's valid, if not, don't make an issue of it, just fix it
baddate = .F.
if empty(ctod(tdte))
tdte = dtoc(date()) && if not, use today's date
baddate = .T.
endif
xdate = chr(val(right(tdte,2))) + + chr(val(left(tdte,2))) + ;
chr(val(substr(tdte,4,2))) && ymd


* compute header info for comparison
nflds = 0
ldata = 1 && 1 byte for the delete flag
=fseek(dbhandle, 32) && position past header
pof = 0
hasmemo = .F.
maxlen = 0 && computed max length of record
do while !feof(dbhandle)
nflds = nflds + 1
fldrec = fread(dbhandle,32)
if left(fldrec,1) = chr(13)
pof = 32*nflds + 1
exit
else
* verify the field rec
if frok(fldrec, @maxlen, @hasmemo)
ldata = ldata + unintel(substr(fldrec, 17, 1)) && accum data rec length
else
* if it's garbage, there's nothing left to do.
=attention(&quot;Fatal Error&quot;, ;
&quot;Invalid field record. Dbf is not repairable&quot;, .T.)
loop
endif
endif
enddo

* if little (<32 bytes) or no data, or premature eof
if feof(dbhandle)
if pof = 0
=attention(&quot;Fatal Error&quot;, ;
&quot;No header delimiter found. Dbf is not repairable&quot;, .T.)
loop
else && probably empty dbf
if len(fldrec) <= 1 && no data after delimiter
dbfempty = .T.
else
dbfempty = .F. && less than 32 bytes of data, so check
if ldata > 31 && inconsistency we can fix
wait window timeout 5 &quot;Hdr/Data Length Inconsistency&quot;
endif
endif
endif
else
dbfempty = .F. && normal case
endif

* compute how many records there actually are
nrecs = int((fsize - pof - 1)/ldata)


if maxlen + 1 # ldata && we'll fix this
wait window timeout 5 &quot;Data Length inconsistency&quot;
endif

if !hasmemo and hasfpt && very odd . . .
=attention(&quot;For your information . . .&quot;, ;
&quot;There is an .fpt file with the same name as this dbf,&quot; + chr(13) + ;
&quot;although this dbf does not have any memo fields.&quot;, .T.)
endif

if hasmemo and !hasfpt && missing fpt file, but fix whatever else we can
=attention(&quot;For your information . . .&quot;, ;
&quot;There is no .fpt file for this dbf!&quot; + chr(13) + ;
&quot;To salvage data, make a copy without the memo fields!&quot;, .T.)
endif

wait clear

* if there is anything wrong with the header, make a new one
if xpof # pof or xnrecs # nrecs or xldata # ldata or ;
xdate # substr(hdr, 2, 3) ;
or memotype # hasmemo or hasmemo and xhdrtype#chr(245) ;
or !hasmemo and xhdrtype # chr(3) or baddate

if attention(&quot;Please tell me . . .&quot;, &quot;This dbf has a bad header.&quot; + chr(13) + ;
&quot;Should I repair it?&quot
wait window nowait &quot;Repairing dbf . . .&quot;
=backup(dbname, @dbhandle)
=fseek(dbhandle,0) && position at beginning of header
* construct valid header and write it
newhdr = iif(hasmemo, chr(245), chr(3)) ;
+ xdate + intel(nrecs,4) + intel(pof,2) + intel(ldata,2) ;
+ substr(hdr,13,20) && take the rest including code page, as is
=fwrite(dbhandle, newhdr)
if ferror() = 0
wait window timeout 3 &quot;dbf Repair successful!&quot;
else
wait window timeout 3 &quot;New dbf header not written. Repair not done!&quot;

endif
endif
else

=attention(&quot;For your information . . .&quot;, &quot;This dbf is OK!&quot;, .T.)

endif

wait clear

* dbf part is all done
* Now see if there is an fpt to repair

if hasmemo and hasfpt

envblksz = set('BLOCKSIZE') && the environment blocksize, default 64
fpthandle = fopen(fptname, 12)
if ferror() # 0
wait window timeout 5 &quot;Can't open fpt! Repair not made!&quot;
loop
else
wait window nowait &quot;Analyzing fpt&quot;
endif

fpthdr = fread(fpthandle, 8) && get fpt header
if ferror() # 0
wait window timeout 5 &quot;Can't read fpt! Repair not made!&quot;
loop
endif

size = fseek(fpthandle, 0, 2) && file size
fptblksz = unltor(substr(fpthdr, 7, 2)) && the block size shown in the fpt
fptptr = unltor(substr(fpthdr, 1, 4)) &&fpt ptr to next available block

* pointer to next available memo block times blocksize
* should equal filesize, since pointer starts counting at 0

if fptptr # int(size/fptblksz)
valok = .F.

* This version requires manual input of correct blocksize

do while !valok
y = attention2(&quot;Possible Blocksize Error&quot;, ;
+ &quot;fpt file shows a blocksize of &quot; + alltrim(str(fptblksz)) ;
+ &quot;. Default is &quot; + alltrim(str(envblksz)) + &quot;. Value to use:&quot;, ;
envblksz)

if y > 0 and y = int && must be a positive integer
valok = .T.
else
if y = 0
exit
else
wait window nowait ;
&quot;Blocksize must be a positive integer!&quot;
endif
endif
enddo
if y = 0 && if no value was supplied, assume user wants to cancel
wait window timeout 3 &quot;fpt repair cancelled&quot;
loop
else && easy to fix it, now that all the work is done
wait window nowait &quot;Repairing fpt . . .&quot;
=backup(fptname, @fpthandle)
fptblksz = y
* if blocksize < 33 it represents a multiple of 512
fptblksz = iif(fptblksz < 33, fptblksz*512, fptblksz)
fptptr = int(size/fptblksz)
newhdr = ltor(fptptr,4) + chr(0) + chr(0) + ltor(fptblksz, 2)
=fseek(fpthandle, 0)
=fwrite(fpthandle, newhdr)
if ferror() = 0
wait window timeout 3 &quot;fpt Repair successful!&quot;
else
wait window timeout 3 &quot;New fpt header not written. Repair not done!&quot;

endif

endif
else
wait window timeout 3 'fpt is OK!'
endif

endif
close all
wait clear
enddo
close all
wait clear

* restore the environment
set view to (home + vfn +'.VUE')
delete file (home + vfn + '.VUE')

return

*******************************************************************
*
* User defined functions
*
* Note: FoxPro uses both Intel style and normal (=sane) numbers
*
*******************************************************************

function unintel && convert from intel 8086 format numbers
parameters x
private all
res = 0
for i = len(x) to 1 step - 1
res = res * 256 + asc(substr(x, i, 1))
endfor
return res

function intel && convert to intel 8086 format numbers
parameters num, digs
private all
res = ''
for i = 1 to digs
res = res + chr(mod(num, 256))
num = int(num/256)
endfor
return res

function unltor && convert from l -> r format #s
parameters x
private all
res = 0
for i = 1 to len(x)
res = res *256 + asc(substr(x, i, 1))
endfor
return res

function ltor && convert to l -> r format #s
parameters num, digs
res = ''
for i = 1 to digs && for the desired number of digits
res = chr(mod(num, 256)) + res
num = int(num/256)
endfor
return res

function frok && check the validity of a field record in the dbf header
parameters fr, maxlen, hasmemo
private all
*check name
nameok = .T. && assume good until proven bad

for i = 10 to 1 step - 1 && count nulls, if any, at end of name
if substr(fr, i, 1) = chr(0)
loop
else
exit
endif
endfor

if !isalpha(left(fr,1)) && make sure name begins with an alpha
nameok = .F.
endif

for j = 2 to i && validate characters 2 ==> end
x = substr(fr, i, 1)
if !(isalpha(x) or isdigit(x) or x='_')
nameok = .F.
exit
endif
endfor

* Type has to be one of these characters
typeok = iif(substr(fr, 12, 1)$'CNLMGDFP', .T., .F.)

hasmemo = hasmemo or substr(fr, 12, 1)$'MGP' && is there a memo type field?

* accumulate record length in maxlen
fl = asc(substr(fr, 17, 1)) && field length
* find max of field displacement + length - 1
maxlen = max(maxlen, unintel(substr(fr, 13, 4)) + fl - 1)

* validate decimal places
decok = iif(asc(substr(fr, 18, 1)) < fl, .T., .F.)
return nameok and typeok and decok && .T. if everything's good



* *********************************************************
* * attention() -- Puts up a 1 or 2-button dialog box
* * Should be pretty non-platform-specific
* *********************************************************

function attention
parameter titletxt, msg, ok && if 'ok' is present, only use &quot;OK&quot; button, return .T.
private tmsg

tmsg = alltrim(msg)
SET BORDER TO PANEL
DEFINE WINDOW chat ;
AT 5, 9 ;
SIZE 10,66 ;
TITLE titletxt ;
NOCLOSE ;
SYSTEM
MOVE WINDOW chat CENTER

ACTIVATE WINDOW chat
@ 2,MAX(0,(3+max(0,0.5*(60-LEN(tmsg))))) SAY tmsg ;
SIZE 2,60

if parameters() = 3 && it's information only
@ 6,28 GET mresponse ;
PICTURE &quot;@*HT3 \!OK&quot; ;
SIZE 2,8,1 ;
DEFAULT 1
else
@ 6,23 GET mresponse ;
PICTURE &quot;@*HT3 \!OK;\?No&quot; ;
SIZE 2,8,1 ;
DEFAULT 1
endif

READ MODAL
RELEASE WINDOW chat

if parameters() = 3 && Information only case
return .T.
else
if mresponse = 1
return .T.
else
return .F.
endif
endif




* *********************************************************
* * attention2() -- Puts up a 2-button dialog box and gets a value
* *********************************************************

function attention2
parameter titletxt, msg, val
private tmsg
set readborder on
tmsg = alltrim(msg)
SET BORDER TO PANEL
DEFINE WINDOW chat ;
AT 5, 9 ;
SIZE 10,66 ;
TITLE titletxt ;
NOCLOSE ;
SYSTEM
MOVE WINDOW chat CENTER

ACTIVATE WINDOW chat
@ 2,MAX(0,(3+max(0,0.5*(60-LEN(tmsg))))) SAY tmsg ;
SIZE 2,60

@ 3, 23 GET value ;
PICTURE &quot;99999&quot; ;
SIZE 1,5 ;
DEFAULT val

@ 6,23 GET mresponse ;
PICTURE &quot;@*HT3 \!OK;\?No&quot; ;
SIZE 2,8,1 ;
DEFAULT 1

READ MODAL
RELEASE WINDOW chat
set readborder off
if mresponse = 1
return value
else
return 0
endif


* ******************************************************
* *
* * Create a backup of file being repaired, with
* * extension reversed.
* *
* ******************************************************

function backup
parameters fname, fhandle
private all

* get the extension
bext = trim(right(fname, len(fname) - rat('.', fname)))
* and the name
bname = left(fname, at('.', fname))

* reverse the extension
revext = ''
for i = 1 to len(bext)
revext = revext + substr(bext, len(bext) + 1 - i, 1)
endfor

* If an old backup file exists, delete it
if file(bname + revext)
delete file (bname + revext)
endif

* close the handle so we won't get a 'file in use'
=fclose(fhandle)

* make the backup copy
copy file (bname + bext) to (bname + revext)

* re-open the file
fhandle = fopen(fname, 12)
return

******** END FIXDBFLT.PRG

 

[acorbally]

What should I look for on the website you gave me?

 

[acorbally]

I copied the prg you added in and tried to use it. I got a message &quot;fpt is ok&quot;. It did not fix my corrupt memo file either.

 

[rob444]

Then what leads you to the conclusion the memo file is corrupted?
Please be specific.

Rob.

 

[acorbally]

I am seeing many carriage return or pipe looking symbols. The memo has other recipients information in the memo. I have seen this before. I know it is corrupt. I usually have to shift bits, but I can't figure out how to get to that 10 bit pointer that shows where the block is in the fpt file.

 

[rob444]

The pointer to the block in the memo field is in the DBF file and it is 4 bytes (32 bits) long.

If you had VFP 6 or higher I would have a utility that perhaps could fix your FPT file.

Rob.

 

[acorbally]

Do you have detailed instructions on how to step through starting with the dbf then via the pointer into the fpt? I am completely lost.

 

[rob444]

I'm working on a program to restore data from damaged dbf's and ftp's and I'm analysing the ftp files now.
I haven't figured it out yet.

Rob.

 

[rob444]

I mean fpt's instead of ftp's...

Rob.

 

[acorbally]

Please let me know when you do. I would ever so greatly appreciate it.

Thanks again.

 

[rob444]

Get recovers.app from:

http://www.rbftp.com/transfer/foxpro/RECOVERS.APP

Just run this app.

Good luck,
Rob.

 

[acorbally]

I did and I get an error that it is a demo version and only able to read *.dbf files with the same file size as the demo dbf's. My dbf is not the same size. It did not fix.

 

[rob444]

I'll fix it tomorrow, for now I'm going to get some sleep.

Rob.

 

[rob444]

aanewlon,

redownload and retry.

Rob.

 

[rob444]

aanewlon,

and just another application to have a try at it:

http://www.rbftp.com/transfer/foxpro/cmrepair26.zip

Rob.

 

[acorbally]

The redownload worked. I think. It completely deleted the comments from the corrupt case, but in the recovrep.txt, it showed the exact record number I was having trouble with. Thank You Thank You Thank You Thank You Thank You
You are a saint.

Andrea