contrib/subtree: ensure only one rev is provided
[git/git.git] / Documentation / git-fsck.txt
1 git-fsck(1)
2 ===========
3
4 NAME
5 ----
6 git-fsck - Verifies the connectivity and validity of the objects in the database
7
8
9 SYNOPSIS
10 --------
11 [verse]
12 'git fsck' [--tags] [--root] [--unreachable] [--cache] [--no-reflogs]
13 [--[no-]full] [--strict] [--verbose] [--lost-found]
14 [--[no-]dangling] [--[no-]progress] [--connectivity-only]
15 [--[no-]name-objects] [<object>*]
16
17 DESCRIPTION
18 -----------
19 Verifies the connectivity and validity of the objects in the database.
20
21 OPTIONS
22 -------
23 <object>::
24 An object to treat as the head of an unreachability trace.
25 +
26 If no objects are given, 'git fsck' defaults to using the
27 index file, all SHA-1 references in `refs` namespace, and all reflogs
28 (unless --no-reflogs is given) as heads.
29
30 --unreachable::
31 Print out objects that exist but that aren't reachable from any
32 of the reference nodes.
33
34 --[no-]dangling::
35 Print objects that exist but that are never 'directly' used (default).
36 `--no-dangling` can be used to omit this information from the output.
37
38 --root::
39 Report root nodes.
40
41 --tags::
42 Report tags.
43
44 --cache::
45 Consider any object recorded in the index also as a head node for
46 an unreachability trace.
47
48 --no-reflogs::
49 Do not consider commits that are referenced only by an
50 entry in a reflog to be reachable. This option is meant
51 only to search for commits that used to be in a ref, but
52 now aren't, but are still in that corresponding reflog.
53
54 --full::
55 Check not just objects in GIT_OBJECT_DIRECTORY
56 ($GIT_DIR/objects), but also the ones found in alternate
57 object pools listed in GIT_ALTERNATE_OBJECT_DIRECTORIES
58 or $GIT_DIR/objects/info/alternates,
59 and in packed Git archives found in $GIT_DIR/objects/pack
60 and corresponding pack subdirectories in alternate
61 object pools. This is now default; you can turn it off
62 with --no-full.
63
64 --connectivity-only::
65 Check only the connectivity of tags, commits and tree objects. By
66 avoiding to unpack blobs, this speeds up the operation, at the
67 expense of missing corrupt objects or other problematic issues.
68
69 --strict::
70 Enable more strict checking, namely to catch a file mode
71 recorded with g+w bit set, which was created by older
72 versions of Git. Existing repositories, including the
73 Linux kernel, Git itself, and sparse repository have old
74 objects that triggers this check, but it is recommended
75 to check new projects with this flag.
76
77 --verbose::
78 Be chatty.
79
80 --lost-found::
81 Write dangling objects into .git/lost-found/commit/ or
82 .git/lost-found/other/, depending on type. If the object is
83 a blob, the contents are written into the file, rather than
84 its object name.
85
86 --name-objects::
87 When displaying names of reachable objects, in addition to the
88 SHA-1 also display a name that describes *how* they are reachable,
89 compatible with linkgit:git-rev-parse[1], e.g.
90 `HEAD@{1234567890}~25^2:src/`.
91
92 --[no-]progress::
93 Progress status is reported on the standard error stream by
94 default when it is attached to a terminal, unless
95 --no-progress or --verbose is specified. --progress forces
96 progress status even if the standard error stream is not
97 directed to a terminal.
98
99 DISCUSSION
100 ----------
101
102 git-fsck tests SHA-1 and general object sanity, and it does full tracking
103 of the resulting reachability and everything else. It prints out any
104 corruption it finds (missing or bad objects), and if you use the
105 `--unreachable` flag it will also print out objects that exist but that
106 aren't reachable from any of the specified head nodes (or the default
107 set, as mentioned above).
108
109 Any corrupt objects you will have to find in backups or other archives
110 (i.e., you can just remove them and do an 'rsync' with some other site in
111 the hopes that somebody else has the object you have corrupted).
112
113 If core.commitGraph is true, the commit-graph file will also be inspected
114 using 'git commit-graph verify'. See linkgit:git-commit-graph[1].
115
116 Extracted Diagnostics
117 ---------------------
118
119 expect dangling commits - potential heads - due to lack of head information::
120 You haven't specified any nodes as heads so it won't be
121 possible to differentiate between un-parented commits and
122 root nodes.
123
124 missing sha1 directory '<dir>'::
125 The directory holding the sha1 objects is missing.
126
127 unreachable <type> <object>::
128 The <type> object <object>, isn't actually referred to directly
129 or indirectly in any of the trees or commits seen. This can
130 mean that there's another root node that you're not specifying
131 or that the tree is corrupt. If you haven't missed a root node
132 then you might as well delete unreachable nodes since they
133 can't be used.
134
135 missing <type> <object>::
136 The <type> object <object>, is referred to but isn't present in
137 the database.
138
139 dangling <type> <object>::
140 The <type> object <object>, is present in the database but never
141 'directly' used. A dangling commit could be a root node.
142
143 hash mismatch <object>::
144 The database has an object whose hash doesn't match the
145 object database value.
146 This indicates a serious data integrity problem.
147
148 Environment Variables
149 ---------------------
150
151 GIT_OBJECT_DIRECTORY::
152 used to specify the object database root (usually $GIT_DIR/objects)
153
154 GIT_INDEX_FILE::
155 used to specify the index file of the index
156
157 GIT_ALTERNATE_OBJECT_DIRECTORIES::
158 used to specify additional object database roots (usually unset)
159
160 GIT
161 ---
162 Part of the linkgit:git[1] suite