1 git-fsck(1)
2 ===========
4 NAME
5 ----
6 git-fsck - Verifies the connectivity and validity of the objects in the database
9 SYNOPSIS
10 --------
11 [verse]
12 'git-fsck' [--tags] [--root] [--unreachable] [--cache] [--no-reflogs]
13 [--full] [--strict] [--verbose] [--lost-found] [<object>*]
15 DESCRIPTION
16 -----------
17 Verifies the connectivity and validity of the objects in the database.
19 OPTIONS
20 -------
21 <object>::
22 An object to treat as the head of an unreachability trace.
23 +
24 If no objects are given, git-fsck defaults to using the
25 index file and all SHA1 references in .git/refs/* as heads.
27 --unreachable::
28 Print out objects that exist but that aren't readable from any
29 of the reference nodes.
31 --root::
32 Report root nodes.
34 --tags::
35 Report tags.
37 --cache::
38 Consider any object recorded in the index also as a head node for
39 an unreachability trace.
41 --no-reflogs::
42 Do not consider commits that are referenced only by an
43 entry in a reflog to be reachable. This option is meant
44 only to search for commits that used to be in a ref, but
45 now aren't, but are still in that corresponding reflog.
47 --full::
48 Check not just objects in GIT_OBJECT_DIRECTORY
49 ($GIT_DIR/objects), but also the ones found in alternate
50 object pools listed in GIT_ALTERNATE_OBJECT_DIRECTORIES
51 or $GIT_DIR/objects/info/alternates,
52 and in packed git archives found in $GIT_DIR/objects/pack
53 and corresponding pack subdirectories in alternate
54 object pools.
56 --strict::
57 Enable more strict checking, namely to catch a file mode
58 recorded with g+w bit set, which was created by older
59 versions of git. Existing repositories, including the
60 Linux kernel, git itself, and sparse repository have old
61 objects that triggers this check, but it is recommended
62 to check new projects with this flag.
64 --verbose::
65 Be chatty.
67 --lost-found::
68 Write dangling objects into .git/lost-found/commit/ or
69 .git/lost-found/other/, depending on type. If the object is
70 a blob, the contents are written into the file, rather than
71 its object name.
73 It tests SHA1 and general object sanity, and it does full tracking of
74 the resulting reachability and everything else. It prints out any
75 corruption it finds (missing or bad objects), and if you use the
76 '--unreachable' flag it will also print out objects that exist but
77 that aren't readable from any of the specified head nodes.
79 So for example
81 git-fsck --unreachable HEAD $(cat .git/refs/heads/*)
83 will do quite a _lot_ of verification on the tree. There are a few
84 extra validity tests to be added (make sure that tree objects are
85 sorted properly etc), but on the whole if "git-fsck" is happy, you
86 do have a valid tree.
88 Any corrupt objects you will have to find in backups or other archives
89 (i.e., you can just remove them and do an "rsync" with some other site in
90 the hopes that somebody else has the object you have corrupted).
92 Of course, "valid tree" doesn't mean that it wasn't generated by some
93 evil person, and the end result might be crap. git is a revision
94 tracking system, not a quality assurance system ;)
96 Extracted Diagnostics
97 ---------------------
99 expect dangling commits - potential heads - due to lack of head information::
100 You haven't specified any nodes as heads so it won't be
101 possible to differentiate between un-parented commits and
102 root nodes.
104 missing sha1 directory '<dir>'::
105 The directory holding the sha1 objects is missing.
107 unreachable <type> <object>::
108 The <type> object <object>, isn't actually referred to directly
109 or indirectly in any of the trees or commits seen. This can
110 mean that there's another root node that you're not specifying
111 or that the tree is corrupt. If you haven't missed a root node
112 then you might as well delete unreachable nodes since they
113 can't be used.
115 missing <type> <object>::
116 The <type> object <object>, is referred to but isn't present in
117 the database.
119 dangling <type> <object>::
120 The <type> object <object>, is present in the database but never
121 'directly' used. A dangling commit could be a root node.
123 warning: git-fsck: tree <tree> has full pathnames in it::
124 And it shouldn't...
126 sha1 mismatch <object>::
127 The database has an object who's sha1 doesn't match the
128 database value.
129 This indicates a serious data integrity problem.
131 Environment Variables
132 ---------------------
134 GIT_OBJECT_DIRECTORY::
135 used to specify the object database root (usually $GIT_DIR/objects)
137 GIT_INDEX_FILE::
138 used to specify the index file of the index
140 GIT_ALTERNATE_OBJECT_DIRECTORIES::
141 used to specify additional object database roots (usually unset)
143 Author
144 ------
145 Written by Linus Torvalds <torvalds@osdl.org>
147 Documentation
148 --------------
149 Documentation by David Greaves, Junio C Hamano and the git-list <git@vger.kernel.org>.
151 GIT
152 ---
153 Part of the linkgit:git[7] suite