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`git worktree repair` knows how to repair the two-way links between the repository and a worktree as long as a link in one or the other direction is sound. For instance, if a linked worktree is moved (without using `git worktree move`), repair is possible because the worktree still knows the location of the repository even though the repository no longer knows where the worktree is. Similarly, if the repository is moved, repair is possible since the repository still knows the locations of the worktrees even though the worktrees no longer know where the repository is. However, if both the repository and the worktrees are moved, then links are severed in both directions, and no repair is possible. This is the case even when the new worktree locations are specified as arguments to `git worktree repair`. The reason for this limitation is twofold. First, when `repair` consults the worktree's gitfile (/path/to/worktree/.git) to determine the corresponding <repo>/worktrees/<id>/gitdir file to fix, <repo> is the old path to the repository, thus it is unable to fix the `gitdir` file at its new location since it doesn't know where it is. Second, when `repair` consults <repo>/worktrees/<id>/gitdir to find the location of the worktree's gitfile (/path/to/worktree/.git), the path recorded in `gitdir` is the old location of the worktree's gitfile, thus it is unable to repair the gitfile since it doesn't know where it is. Fix these shortcomings by teaching `repair` to attempt to infer the new location of the <repo>/worktrees/<id>/gitdir file when the location recorded in the worktree's gitfile has become stale but the file is otherwise well-formed. The inference is intentionally simple-minded. For each worktree path specified as an argument, `git worktree repair` manually reads the ".git" gitfile at that location and, if it is well-formed, extracts the <id>. It then searches for a corresponding <id> in <repo>/worktrees/ and, if found, concludes that there is a reasonable match and updates <repo>/worktrees/<id>/gitdir to point at the specified worktree path. In order for <repo> to be known, `git worktree repair` must be run in the main worktree or bare repository. `git worktree repair` first attempts to repair each incoming /path/to/worktree/.git gitfile to point at the repository, and then attempts to repair outgoing <repo>/worktrees/<id>/gitdir files to point at the worktrees. This sequence was chosen arbitrarily when originally implemented since the order of fixes is immaterial as long as one side of the two-way link between the repository and a worktree is sound. However, for this new repair technique to work, the order must be reversed. This is because the new inference mechanism, when it is successful, allows the outgoing <repo>/worktrees/<id>/gitdir file to be repaired, thus fixing one side of the two-way link. Once that side is fixed, the other side can be fixed by the existing repair mechanism, hence the order of repairs is now significant. Two safeguards are employed to avoid hijacking a worktree from a different repository if the user accidentally specifies a foreign worktree as an argument. The first, as described above, is that it requires an <id> match between the repository and the worktree. That itself is not foolproof for preventing hijack, so the second safeguard is that the inference will only kick in if the worktree's /path/to/worktree/.git gitfile does not point at a repository. Signed-off-by: Eric Sunshine <sunshine@sunshineco.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
Git - fast, scalable, distributed revision control system
Git is a fast, scalable, distributed revision control system with an unusually rich command set that provides both high-level operations and full access to internals.
Git is an Open Source project covered by the GNU General Public License version 2 (some parts of it are under different licenses, compatible with the GPLv2). It was originally written by Linus Torvalds with help of a group of hackers around the net.
Please read the file INSTALL for installation instructions.
Many Git online resources are accessible from https://git-scm.com/ including full documentation and Git related tools.
See Documentation/gittutorial.txt to get started, then see
Documentation/giteveryday.txt for a useful minimum set of commands, and
Documentation/git-<commandname>.txt for documentation of each command.
If git has been correctly installed, then the tutorial can also be
read with man gittutorial or git help tutorial, and the
documentation of each command with man git-<commandname> or git help <commandname>.
CVS users may also want to read Documentation/gitcvs-migration.txt
(man gitcvs-migration or git help cvs-migration if git is
installed).
The user discussion and development of Git take place on the Git mailing list -- everyone is welcome to post bug reports, feature requests, comments and patches to git@vger.kernel.org (read Documentation/SubmittingPatches for instructions on patch submission). To subscribe to the list, send an email with just "subscribe git" in the body to majordomo@vger.kernel.org. The mailing list archives are available at https://lore.kernel.org/git/, http://marc.info/?l=git and other archival sites.
Issues which are security relevant should be disclosed privately to the Git Security mailing list git-security@googlegroups.com.
The maintainer frequently sends the "What's cooking" reports that list the current status of various development topics to the mailing list. The discussion following them give a good reference for project status, development direction and remaining tasks.
The name "git" was given by Linus Torvalds when he wrote the very first version. He described the tool as "the stupid content tracker" and the name as (depending on your mood):
- random three-letter combination that is pronounceable, and not actually used by any common UNIX command. The fact that it is a mispronunciation of "get" may or may not be relevant.
- stupid. contemptible and despicable. simple. Take your pick from the dictionary of slang.
- "global information tracker": you're in a good mood, and it actually works for you. Angels sing, and a light suddenly fills the room.
- "goddamn idiotic truckload of sh*t": when it breaks