Documentation/git-fsck-objects.txt

   1 git-fsck-objects(1)
   2 ===================
   3
   4 NAME
   5 ----
   6 git-fsck-objects - Verifies the connectivity and validity of the objects in the database
   7
   8
   9 SYNOPSIS
  10 --------
  11 [verse]
  12 'git-fsck-objects' [--tags] [--root] [--unreachable] [--cache]
  13                  [--standalone | --full] [--strict] [<object>*]
  14
  15 DESCRIPTION
  16 -----------
  17 Verifies the connectivity and validity of the objects in the database.
  18
  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-objects defaults to using the
  25 index file and all SHA1 references in .git/refs/* as heads.
  26
  27 --unreachable::
  28         Print out objects that exist but that aren't readable from any
  29         of the reference nodes.
  30
  31 --root::
  32         Report root nodes.
  33
  34 --tags::
  35         Report tags.
  36
  37 --cache::
  38         Consider any object recorded in the index also as a head node for
  39         an unreachability trace.
  40
  41 --standalone::
  42         Limit checks to the contents of GIT_OBJECT_DIRECTORY
  43         ($GIT_DIR/objects), making sure that it is consistent and
  44         complete without referring to objects found in alternate
  45         object pools listed in GIT_ALTERNATE_OBJECT_DIRECTORIES,
  46         nor packed git archives found in $GIT_DIR/objects/pack;
  47         cannot be used with --full.
  48
  49 --full::
  50         Check not just objects in GIT_OBJECT_DIRECTORY
  51         ($GIT_DIR/objects), but also the ones found in alternate
  52         object pools listed in GIT_ALTERNATE_OBJECT_DIRECTORIES,
  53         and in packed git archives found in $GIT_DIR/objects/pack
  54         and corresponding pack subdirectories in alternate
  55         object pools; cannot be used with --standalone.
  56
  57 --strict::
  58         Enable more strict checking, namely to catch a file mode
  59         recorded with g+w bit set, which was created by older
  60         versions of git.  Existing repositories, including the
  61         Linux kernel, git itself, and sparse repository have old
  62         objects that triggers this check, but it is recommended
  63         to check new projects with this flag.
  64
  65 It tests SHA1 and general object sanity, and it does full tracking of
  66 the resulting reachability and everything else. It prints out any
  67 corruption it finds (missing or bad objects), and if you use the
  68 '--unreachable' flag it will also print out objects that exist but
  69 that aren't readable from any of the specified head nodes.
  70
  71 So for example
  72
  73         git-fsck-objects --unreachable HEAD $(cat .git/refs/heads/*)
  74
  75 will do quite a _lot_ of verification on the tree. There are a few
  76 extra validity tests to be added (make sure that tree objects are
  77 sorted properly etc), but on the whole if "git-fsck-objects" is happy, you
  78 do have a valid tree.
  79
  80 Any corrupt objects you will have to find in backups or other archives
  81 (ie you can just remove them and do an "rsync" with some other site in
  82 the hopes that somebody else has the object you have corrupted).
  83
  84 Of course, "valid tree" doesn't mean that it wasn't generated by some
  85 evil person, and the end result might be crap. git is a revision
  86 tracking system, not a quality assurance system ;)
  87
  88 Extracted Diagnostics
  89 ---------------------
  90
  91 expect dangling commits - potential heads - due to lack of head information::
  92         You haven't specified any nodes as heads so it won't be
  93         possible to differentiate between un-parented commits and
  94         root nodes.
  95
  96 missing sha1 directory '<dir>'::
  97         The directory holding the sha1 objects is missing.
  98
  99 unreachable <type> <object>::
 100         The <type> object <object>, isn't actually referred to directly
 101         or indirectly in any of the trees or commits seen. This can
 102         mean that there's another root node that you're not specifying
 103         or that the tree is corrupt. If you haven't missed a root node
 104         then you might as well delete unreachable nodes since they
 105         can't be used.
 106
 107 missing <type> <object>::
 108         The <type> object <object>, is referred to but isn't present in
 109         the database.
 110
 111 dangling <type> <object>::
 112         The <type> object <object>, is present in the database but never
 113         'directly' used. A dangling commit could be a root node.
 114
 115 warning: git-fsck-objects: tree <tree> has full pathnames in it::
 116         And it shouldn't...
 117
 118 sha1 mismatch <object>::
 119         The database has an object who's sha1 doesn't match the
 120         database value.
 121         This indicates a serious data integrity problem.
 122
 123 Environment Variables
 124 ---------------------
 125
 126 GIT_OBJECT_DIRECTORY::
 127         used to specify the object database root (usually $GIT_DIR/objects)
 128
 129 GIT_INDEX_FILE::
 130         used to specify the index file of the index
 131
 132 GIT_ALTERNATE_OBJECT_DIRECTORIES::
 133         used to specify additional object database roots (usually unset)
 134
 135 Author
 136 ------
 137 Written by Linus Torvalds <torvalds@osdl.org>
 138
 139 Documentation
 140 --------------
 141 Documentation by David Greaves, Junio C Hamano and the git-list <git@vger.kernel.org>.
 142
 143 GIT
 144 ---
 145 Part of the gitlink:git[7] suite
 146