The signature for the reflog is not something which changes
dynamically. Almost all uses will be NULL, since we want for the
repository's default identity to be used, making it noise.
In order to allow for changing the identity, we instead provide
git_repository_set_ident() and git_repository_ident() which allow a user
to override the choice of signature.
The stash is implemented as the refs/stash reference and its reflog. In
order to modify the reflog, we need avoid races by making sure we're the
only ones allowed to modify the reflog.
We achieve this via the transactions API. Locking the reference gives us
exclusive write access, letting us modify and write it without races.
To emulate git, stash should not remove untracked git repositories
inside the parent repo, and checkout's REMOVE_UNTRACKED should
also skip over these items.
`git stash` actually prints a warning message for these items.
That should be possible with a checkout notify callback if you
wanted to, although it would require a bit of extra logic as things
are at the moment.
Any well-behaved program should write a descriptive message to the
reflog whenever it updates a reference. Let's make this more prominent
by removing the version without the reflog parameters.
This changes the behavior of callbacks so that the callback error
code is not converted into GIT_EUSER and instead we propagate the
return value through to the caller. Instead of using the
giterr_capture and giterr_restore functions, we now rely on all
functions to pass back the return value from a callback.
To avoid having a return value with no error message, the user
can call the public giterr_set_str or some such function to set
an error message. There is a new helper 'giterr_set_callback'
that functions can invoke after making a callback which ensures
that some error message was set in case the callback did not set
one.
In places where the sign of the callback return value is
meaningful (e.g. positive to skip, negative to abort), only the
negative values are returned back to the caller, obviously, since
the other values allow for continuing the loop.
The hardest parts of this were in the checkout code where positive
return values were overloaded as meaningful values for checkout.
I fixed this by adding an output parameter to many of the internal
checkout functions and removing the overload. This added some
code, but it is probably a better implementation.
There is some funkiness in the network code where user provided
callbacks could be returning a positive or a negative value and
we want to rely on that to cancel the loop. There are still a
couple places where an user error might get turned into GIT_EUSER
there, I think, though none exercised by the tests.
This continues auditing all the places where GIT_EUSER is being
returned and making sure to clear any existing error using the
new giterr_user_cancel helper. As a result, places that relied
on intercepting GIT_EUSER but having the old error preserved also
needed to be cleaned up to correctly stash and then retrieve the
actual error.
Additionally, as I encountered places where error codes were not
being propagated correctly, I tried to fix them up. A number of
those fixes are included in the this commit as well.
Whenever a reference is created or updated, we need to write to the
reflog regardless of whether the user gave us a message, so we shouldn't
leave that to the ref frontend, but integrate it into the backend.
This also eliminates the race between ref update and writing to the
reflog, as we protect the reflog with the ref lock.
As an additional benefit, this reflog append on the backend happens by
appending to the file instead of parsing and rewriting it.
This lays groundwork for separating formatting options from diff
creation options. This groups the formatting flags separately
from the diff list creation flags and reorders the options. This
also tweaks some APIs to further separate code that uses patches
from code that just looks at git_diffs.
This makes no functional change to diff but renames a couple of
the objects and splits the new git_patch (formerly git_diff_patch)
into a new header file.
References and their logs are logically coupled, let's make it so in
the code by moving the fs-based reflog implementation to live next to
the fs-based refs one.
As part of the change, make the function take names rather than
references, as only the names are relevant when looking up and
handling reflogs.
Unfortunately git-core uses the term "unborn branch" and "orphan
branch" interchangeably. However, "orphan" is only really there for
the checkout command, which has the `--orphan` option so it doesn't
actually create the branch.
Branches never have parents, so the distinction of a branch with no
parents is odd to begin with. Crucially, the error messages deal with
unborn branches, so let's use that.
This is a significant reorganization of the diff code to break it
into a set of more clearly distinct files and to document the new
organization. Hopefully this will make the diff code easier to
understand and to extend.
This adds a new `git_diff_driver` object that looks of diff driver
information from the attributes and the config so that things like
function content in diff headers can be provided. The full driver
spec is not implemented in the commit - this is focused on the
reorganization of the code and putting the driver hooks in place.
This also removes a few #includes from src/repository.h that were
overbroad, but as a result required extra #includes in a variety
of places since including src/repository.h no longer results in
pulling in the whole world.
Stash was sometimes obscuring the actual error code, replacing it
with a -1 when there was more descriptive value. This updates
stash to preserve the original error code more reliably along
with a variety of other error handling tweaks.
I believe this is an improvement, but arguably, preserving the
underlying error code may result in values that are harder to
interpret by the caller who does not understand the internals.
Discussion is welcome!
I've tried to map out the detailed behaviors of checkout and make
sure that we're handling the various cases correctly, along with
providing options to allow us to emulate "git checkout" and "git
checkout-index" with the various flags. I've thrown away flags
in the checkout API that seemed like clutter and added some new
ones. Also, I've converted the conflict callback to a general
notification callback so we can emulate "git checkout" output and
display "dirty" files.
As of this commit, the new behavior is not working 100% but some
of that is probably baked into tests that are not testing the
right thing. This is a decent snapshot point, I think, along the
way to getting the update done.
The diff constructor functions had some confusing names, where the
"old" side of the diff was coming after the "new" side. This
reverses the order in the function name to make it less confusing.
Specifically...
* git_diff_index_to_tree becomes git_diff_tree_to_index
* git_diff_workdir_to_index becomes git_diff_index_to_workdir
* git_diff_workdir_to_tree becomes git_diff_tree_to_workdir
This makes the diff functions that take callbacks both take
the payload parameter after the callback function pointers and
pass the payload as the last argument to the callback function
instead of the first. This should make them consistent with
other callbacks across the API.
