config: allow inaccessible configuration under $HOME

The changes v1.7.12.1~2^2~4 (config: warn on inaccessible files,
2012-08-21) and v1.8.1.1~22^2~2 (config: treat user and xdg config
permission problems as errors, 2012-10-13) were intended to prevent
important configuration (think "[transfer] fsckobjects") from being
ignored when the configuration is unintentionally unreadable (for
example with EIO on a flaky filesystem, or with ENOMEM due to a DoS
attack).  Usually ~/.gitconfig and ~/.config/git are readable by the
current user, and if they aren't then it would be easy to fix those
permissions, so the damage from adding this check should have been
minimal.

Unfortunately the access() check often trips when git is being run as
a server.  A daemon (such as inetd or git-daemon) starts as "root",
creates a listening socket, and then drops privileges, meaning that
when git commands are invoked they cannot access $HOME and die with

 fatal: unable to access '/root/.config/git/config': Permission denied

Any patch to fix this would have one of three problems:

  1. We annoy sysadmins who need to take an extra step to handle HOME
     when dropping privileges (the current behavior, or any other
     proposal that they have to opt into).

  2. We annoy sysadmins who want to set HOME when dropping privileges,
     either by making what they want to do impossible, or making them
     set an extra variable or option to accomplish what used to work
     (e.g., a patch to git-daemon to set HOME when --user is passed).

  3. We loosen the check, so some cases which might be noteworthy are
     not caught.

This patch is of type (3).

Treat user and xdg configuration that are inaccessible due to
permissions (EACCES) as though no user configuration was provided at
all.

An alternative method would be to check if $HOME is readable, but that
would not help in cases where the user who dropped privileges had a
globally readable HOME with only .config or .gitconfig being private.

This does not change the behavior when /etc/gitconfig or .git/config
is unreadable (since those are more serious configuration errors),
nor when ~/.gitconfig or ~/.config/git is unreadable due to problems
other than permissions.

Signed-off-by: Jonathan Nieder <jrnieder@gmail.com>
Improved-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
remote-bzr: cleanup CustomTree

This code was not used at all.

Signed-off-by: Felipe Contreras <felipe.contreras@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
remote-bzr: delay blob fetching until the very end

Might be more efficient, but the real reason to use the marks will be
revealed in upcoming patches.

Signed-off-by: Felipe Contreras <felipe.contreras@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
remote-bzr: fix order of locking in CustomTree

It doesn't seem to make any difference, but revision_tree() requires a
lock.

Signed-off-by: Felipe Contreras <felipe.contreras@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
remote-bzr: always try to update the worktree

And fail properly when we can't.

Signed-off-by: Felipe Contreras <felipe.contreras@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
remote-bzr: add support to push merges

In order to do that, we need to store the marks of every file, so that
they can be fetched when needed. Unfortunately we can't tell bazaar that
nothing changed, we need to send the data so that it can figure it out
by itself.

And since it will be requesting a bunch of information by the file_id,
it's better to have a helper dict (rev_files), so that we can fetch it
quickly.

Signed-off-by: Felipe Contreras <felipe.contreras@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
remote-bzr: fixes for branch diverge

If the branches diverge we want to reset the pointer to where the remote
actually is. Since we can access remote branches just as easily as local
ones, let's do so.

Signed-off-by: Felipe Contreras <felipe.contreras@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
remote-bzr: fix partially pushed merge

If part of the merge was already pushed, we don't have the blob_marks
available, however, the commits are already stored in bazaar, so we can
use the revision_tree to fetch the contents.

We want to do this only when there's no other option.

There's no easy way to test this.

Signed-off-by: Felipe Contreras <felipe.contreras@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
remote-bzr: use branch variable when appropriate

There should be no functional changes. Basically we want to reserve the
'repo' variable.

Signed-off-by: Felipe Contreras <felipe.contreras@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
remote-bzr: add support for bzr repos

In bazaar, a repository can contain multiple branches, and previously we
were supporting only one branch at a time. Now we fetch them all.

Signed-off-by: Felipe Contreras <felipe.contreras@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
remote-bzr: fix branch names

When branches have '/' in their name (aka. sub-branches), bazaar seems
to choke while creating the new directory.

Also, git cannot have both 'foo' and 'foo/bar'.

So let's replace slashes with a plus sign.

Signed-off-by: Felipe Contreras <felipe.contreras@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
remote-bzr: add support for shared repo

This way all the remotes share the same data, so adding multiple
remotes, or renaming them doesn't create extra overhead.

Signed-off-by: Felipe Contreras <felipe.contreras@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
remote-bzr: improve author sanitazion

So that we don't end up with '<None>', and also synchronize it with the
one from remote-hg.

Signed-off-by: Felipe Contreras <felipe.contreras@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
remote-bzr: add custom method to find branches

The official method is incredibly inefficient and slow.

Signed-off-by: Felipe Contreras <felipe.contreras@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
remote-bzr: add option to specify branches

We might not want all the branches. And branch handling in bazaar is
rather tricky, so it's safer to simply specify them.

Signed-off-by: Felipe Contreras <felipe.contreras@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
remote-bzr: improve progress reporting

No need to manually count the revisions, and also, this would help to
iterate more properly.

Signed-off-by: Felipe Contreras <felipe.contreras@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
remote-bzr: iterate revisions properly

This way we don't need to store the list of all the revisions, which
doesn't seem to be very memory efficient with bazaar's design, for
whatever reason.

Signed-off-by: Felipe Contreras <felipe.contreras@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
remote-bzr: delay peer branch usage

So it doesn't time out.

Signed-off-by: Felipe Contreras <felipe.contreras@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
remote-bzr: access branches only when needed

Bazaar doesn't seem to be tested for multiple usage of branches, so
resources seem to be leaked all over. Let's try to minimize this by
accessing the Branch objects only when needed.

Signed-off-by: Felipe Contreras <felipe.contreras@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
contrib/subtree: don't delete remote branches if split fails

When using "git subtree push" to split out a subtree and push it to a
remote repository, we do not detect if the split command fails which
causes the LHS of the refspec to be empty, deleting the remote branch.

Fix this by pulling the result of the split command into a variable so
that we can die if the command fails.

Reported-by: Steffen Jaeckel <steffen.jaeckel@stzedn.de>
Signed-off-by: John Keeping <john@keeping.me.uk>
Signed-off-by: Junio C Hamano <gitster@pobox.com>