Versioning configuration files on a server: fatal: Unable to create '//etc/.git/index.lock': No such file or directory

Hello all

I'm trying to use git to version all the configuration files on a server:

su cd / git init cd / touch k git add k #this works cd /etc git add hosts

This fails with:

fatal: Unable to create '//etc/.git/index.lock': No such file or directory

I'm running git-1.7.3.2-1.fc14.x86_64.

Is there any way to convince git to work in this scenario?

Regards

Albert

Hey,

I've been using git for exactly this purpose succesfully for a while now (git 1.5.6.5 from Debian stable and I think also 1.7.2.3 from Debian testing). The only problem I've found was that, with the former version, a lot of operations need to happen while the current dir is /, otherwise it wouldn't find the git repository properly (or do other weird stuff). This problem was gone in the latter version.

This sounds like git assumes /etc/.git exists, but it really doesn't. Not sure why that happens.

Gr.

Matthijs

Hi all,

Coming back to the testing machine I was using this on, I see this problem as well now. I'm pretty sure it wasn't there before, which would mean it was introduced by a recent upgrade.

Checking the logs shows that I was running 1.7.1 before, and now 1.7.2.3 is broken. Downgrading to 1.7.1 indeed removes the problem.

I've rummaged around in the source a bit, haven't found the cause yet (and I'm out of time now).

The issue also still occurs with a fairly recent git master (ca209065f: completion: fix zsh check under bash with 'set -u').

Gr.

Matthijs

On Thu, Nov 18, 2010 at 4:52 PM, Matthijs Kooijman <matthijs@stdin.nl> wrote:

Alternatively, you could try to bisect, with "git bisect", between these two commits, 1.7.2.3=bad and 1.7.1=good. It is roughly 10 steps.

HTH, Santi

On Thu, Nov 18, 2010 at 10:52 PM, Matthijs Kooijman <matthijs@stdin.nl> wrote:

You may be interested in 72ec8ba (Support working directory located at root - 2010-02-14). t1509 reports the breakages. Unfortunately this kind of tests can't be run automatically

On Thu, Nov 18, 2010 at 11:07 PM, Nguyen Thai Ngoc Duy <pclouds@gmail.com> wrote:

I think 490544b (get_cwd_relative(): do not misinterpret suffix as subdirectory - 2010-05-22) causes it. Haven't fully understood what's going on in that function though :P

Will look again tomorrow, if nobody beats me to it.

Hi Nguyen,

Seems you're right. I just reverted this commit and the problem seems to go away.

In case you're investigation, here's the relevant call to get_cwd_relative in this case is:

Breakpoint 3, get_relative_cwd (buffer=0x756e20 "", size=4096, dir=0x764040 "/") at dir.c:944

Not sure what the return value is, that one got optimized out.

Gr.

Matthijs

Hi folks,

A bit more gdb'ing with -O0, I found the following. get_cwd_relative is called with dir="/". The cwd is "/etc". The stack looks like:

#0 get_relative_cwd (buffer=0x7a44c0 "/etc", size=4096, dir=0x7b1041 "") at dir.c:961 #1 0x00000000004dfdf1 in setup_git_directory () at setup.c:612 #2 0x0000000000404f69 in run_builtin (p=0x75ea10, argc=2, argv=0x7fffffffc918) at git.c:257 #3 0x00000000004051e3 in handle_internal_command (argc=2, argv=0x7fffffffc918) at git.c:431 #4 0x000000000040538a in main (argc=2, argv=0x7fffffffc918) at git.c:516

After the following code runs:

    while (*dir && *dir == *cwd) {
	    dir++; 
	    cwd++;
    }

I have dir="" and cwd="etc". Then the following code runs:

    switch (*cwd) {
    case '\0':
	    return cwd;
    case '/':
	    return cwd + 1;
    default:
	    return NULL;
    }

Since *cwd='e', it returns NULL.

The old code (before 490544b) was:

   if (*cwd == '/')
	   return cwd + 1;
   return cwd;

So this would return "etc".

So, that's what is happens. I think this happens because get_relative_cwd expects dir to not contain a trailing slash. Normally, there is no trailing slash, but in the special case of dir="/" there is (sort of) a trailing slash.

I'm not completely sure how to fix this. Looking at 72ec8ba (Support working directory located at root - 2010-02-14), perhaps something like this?