SVN Checksum Repair

Question

I use subclipse in Flex Builder 3 and recently received this error when trying to commit:

svn: Checksum mismatch for '/Users/redacted/Documents/Flex Builder 3/path/to/my/file.mxml'; expected: 'f8cb275de72776657406154dd3c10348', actual: 'null'

I worked around:

• Executing all other modified files, omitting the nasty.
• Copy the contents of the problem file to the TextMate window
• Removing my project in FlexBuilder / Eclipse
• Validating my project from SVN
• Copy problem file text from TextMate window
• Making changes.

It worked, but I can't help but think about it better. What happens to cause svn error: checksum, and what is the best solution.

Perhaps more importantly, is this a symptom of a bigger problem?

Answer 1

A file in the .svn directory that keeps track of what you checked, when, which version and from where, it is somehow corrupted, for this particular file.

This is no more dangerous or critical than the usual odd-file problem, and may be due to various problems, such as a disruptive program dying in the middle of a change, a power failure, etc.

If this does not happen, I will not do it anymore.

You can fix it by doing what you did, make a copy of your working files, check the new copy and add the modified files.

Please note that this can cause problems if you have a busy project in which you usually have to change the changes.

For example, you and a colleague check a fresh copy and start working on the same file. At some point, your college checks its modifications. When you try to do the same, you get a checksum. If now you make copies of your modified files, do a new check, then subversion will lose information about how your changes should be merged again.

If you did not have a problem in this case, when you checked your modifications, you need to first update the working copy and possibly handle the conflict with your file.

However, if you are doing a new check, complete with changes from your peers, it now looks like you deleted your changes and replaced your own. No conflicts and no indications of subversion, that something was wrong.

Answer 2

There is also a simpler reason than just errors, or disk corruption, etc. I think the most likely reason for this is that someone is writing a recursive text replacement on a working copy without exception .svn files. <w> This means that clean copies of the files (basically the BASE version of the files that are stored in the administrative area .svn) are changed, which invalidates the sum of MD5.

@Andrew Hedges: this also explains why your decision fixes this.

Answer 3

SVN keeps clean copies of all the files you scan buried in .svn directories. This is called a text base. This allows you to quickly differentiate and recover. During various operations, SVN will perform checksums on these text files to catch file corruption problems.

In general, an SVN checksum mismatch means that the file that should not have been modified was somehow modified. What does it mean?

• Disk corruption (bad hard drive or IDE cable)
• Bad RAM
• Bad network link
• Some background process has changed the file behind you (malware)

All this is bad.

HOWEVER , I think your problem is different. Look at the error message. Note that he was expecting some MD5 hashes, but "null" returned instead. If this were a simple file corruption issue, I would expect you to have two different MD5 hashes for the expected / received. The fact that you have "null" means that something else is wrong.

I have two theories:

• Error in SVN.
• Something had an exclusive file lock, and MD5 could not happen.

In case # 1, try upgrading to the latest version of SVN. Perhaps also post this on the svn-devel mailing list ( http://svn.haxx.se ) so that developers can see it.

In case # 2, check if the file is locked. You can download a copy of Process Explorer for verification. Note that you will probably want to know who has the lock in the text database file, and not the actual file that you were trying to commit.

Answer 4

Sometimes I get similar things, usually with files that no one has been around for several weeks. As a rule, if you know that you are not working in the corresponding directory, you can simply delete the directory with the problem and run

 svn update 

to recreate it.

If you have live changes to the directory, then like lassevk, and you yourself have suggested, a more thorough approach is required.

Generally speaking, I would say that it’s nice not to leave the edited files uncommitted and keep a permanent working copy - do not add a whole bunch of additional files to the working copy that you are not going to use. Comment on a regular basis, and then if the working copy goes up, you can simply delete it all and start all over without worrying about what you might or might not lose, and without pain, trying to figure out which files to save.

Answer 5

Just today, I was able to repair this error by checking a copy of the damaged directory in / tmp and replacing the files in the .svn / text-base with the newly joined ones. I wrote the procedure in detail here on my blog . I would be interested to hear from more experienced SVN users what are the advantages and disadvantages of each approach.

Answer 6

try: svn up --force file.c

It worked for me without doing anything extra

Answer 7

I have observed many solutions related to fixing the .svn / entries file with a new design.

This could be a new way (thanks to my colleague):

 - go to work directory where recorder/expected checksum issue occured - call "svn diff" and make sure that there isnt any local modifications - cd .. - remove trouble file directory with "rm -rf" - issue "svn up" command, svn client will restore new fresh files copies 

Answer 8

another, possibly even more scary, workaround for the checksum conflicts I found is as follows:

CAVEAT: make sure your local copy is the most famous version and that any of your project knows what you are doing! (in case it was no longer obvious).

if you know that your local copy of the file is “good,” you can directly delete the file from the SVN server, and then force the local copy.

Syntax

for direct deletion:

svn delete -m "delete corrupted XXXX file" svn + ssh: // username @ svnserver / path / to / XXXX

Good luck

J

Answer 9

Matt, there is an easier way than you described - changing the checksum in the .svn / entries file. Here is the full description: http://maymay.net/blog/2008/06/17/fix-subversion-checksum-mismatch-error-by-editing-svnentries-file/

Answer 10

If this were the problem, our VM all * nix our win32 workstations. some fools created files with the same name (in another case) in the * nix field all sudden checks on Win32 explode ... because the win does not know which of the two files with the same name refers to MD5, the quotes on * nix were fine ... leaving us a little scratch our heads

I was able to update the repo in the win window by copying the ".svn" folders from the * nix window with a good working copy. haven't figured out yet whether it is possible to clear the repo to such an extent that we can perform a full check again.

Answer 11

Another easy way ...

• Update your project to get the latest version.
• Checkout the same version in a different folder
• replace the .svn folder with a new copy with a working copy (I replaced the .svn-base files)

Answer 12

As an alternative to checking for a new copy (which I also had to make after checking all the other parameters), and then merging all your changes that you previously saved, it was supported in the same way, but it saved me a considerable amount of time and maybe some errors:

• Check out the new working copy.
• Copy the .svn folder from the new copy to the damaged copy.
• Voila

Of course, just in case, you should back up your original damaged working copy. In my case, I was free to remove it after I finished, as everything went well.

Answer 13

This will happen when the .svn folder is damaged. Solution: Delete the entire file folder and check the folder again.

Answer 14

• Send only the folder with the problem file from the repository to another place.
• Make sure that the .svn\text-base\<problematic file>.svn-base is identical to the .svn\text-base\<problematic file>.svn-base .
• Make sure that the problem section of the file (all lines of the section) in .svn\entries is identical to the one issued.

Answer 15

You would not believe this, but I really corrected my mistake by deleting the position <scm>...</scm> from the pom.xml intruder file, which I was hoping to verify. It contained the URL of the subversion repository that it checked in (this is the Maven setting for!), But somehow it generated an erroneous checksum for the file during verification.

I literally tried all of the above methods to fix this, but to no avail. Am I faced with a very rare situation where the checksum generator is not strong enough?

Answer 16

I also came across this problem and tried to find quick solutions, tried some solution given in this thread. This is how I solved this problem in my development environment (for me it was a minimal change):

1 Locally remote directory in which the file is damaged (WEB-INF):

  svn: Checksum mismatch for 'path-to-folder\WEB-INF\web.xml': expected: d60cb051162e4a6790a3ea0c9ddfb434 actual: 16885ded2cbc1adc250e4cbbc1427546 

2- The copied and pasted directory (WEB-INF) from the new scan

3- Did svn up, now Eclipse / TortoiseSVN started showing conflict in this directory

4 Marked conflict as resolved

It worked, I was able to update, fix previously damaged web.xml

Answer 17

In my case, the amount was different. All I have done is:

1) Make Disable to split the folder

2) Replace the file from this folder in the .svn directory with my project problem file, which was indicated in the svn-client error message

3) .. Profit!

Answer 18

1) Go to the folder causing the problem 2) Run the svn update --set-depth empty command 3) This folder will be empty and will return an empty folder. 4) synchronization with svn and update.

This work is for me.

Answer 19

Although this is an old problem, I thought I would give 2 cents, since I just struggled with the problem for more than an hour.

The above solutions either didn't work for me or seemed overly complicated.

My solution was to simply delete all svn folders from the project.

find . -name .svn -exec rm -rf {} \;

After that, I again performed a simple project check. Thus, leaving all my uncommitted files intact, but still got a re-creation of all svn files.

Answer 20

I had this problem on ubuntu 14.04 and solved it using the following steps:

• $ cd / var / www / myProject
• $ svn upgrade
• $ svn update

after these steps I can commit the file without errors.

Answer 21

this is how I fixed the problem - v is simple, but as stated above, you need to make sure your copy is the best.

simply

• make a copy of all problem files in the same folder.
• remove old with svn rm
• to commit.
• then rename the copies back to the original file names.
• lock again.

suspect that this probably kills all kinds of change history in this file, so this is a pretty ugly way to do this ...