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 'git-fsck-objects' [--tags] [--root] [--unreachable] [--cache] [--standalone | --full] [--strict] [<object>*]
  12
  13 DESCRIPTION
  14 -----------
  15 Verifies the connectivity and validity of the objects in the database.
  16
  17 OPTIONS
  18 -------
  19 <object>::
  20         An object to treat as the head of an unreachability trace.
  21 +
  22 If no objects are given, git-fsck-objects defaults to using the
  23 index file and all SHA1 references in .git/refs/* as heads.
  24
  25 --unreachable::
  26         Print out objects that exist but that aren't readable from any
  27         of the reference nodes.
  28
  29 --root::
  30         Report root nodes.
  31
  32 --tags::
  33         Report tags.
  34
  35 --cache::
  36         Consider any object recorded in the index also as a head node for
  37         an unreachability trace.
  38
  39 --standalone::
  40         Limit checks to the contents of GIT_OBJECT_DIRECTORY
  41         ($GIT_DIR/objects), making sure that it is consistent and
  42         complete without referring to objects found in alternate
  43         object pools listed in GIT_ALTERNATE_OBJECT_DIRECTORIES,
  44         nor packed git archives found in $GIT_DIR/objects/pack;
  45         cannot be used with --full.
  46
  47 --full::
  48         Check not just objects in GIT_OBJECT_DIRECTORY
  49         ($GIT_DIR/objects), but also the ones found in alternate
  50         object pools listed in GIT_ALTERNATE_OBJECT_DIRECTORIES,
  51         and in packed git archives found in $GIT_DIR/objects/pack
  52         and corresponding pack subdirectories in alternate
  53         object pools; cannot be used with --standalone.
  54
  55 --strict::
  56         Enable more strict checking, namely to catch a file mode
  57         recorded with g+w bit set, which was created by older
  58         versions of git.  Existing repositories, including the
  59         Linux kernel, git itself, and sparse repository have old
  60         objects that triggers this check, but it is recommended
  61         to check new projects with this flag.
  62
  63 It tests SHA1 and general object sanity, and it does full tracking of
  64 the resulting reachability and everything else. It prints out any
  65 corruption it finds (missing or bad objects), and if you use the
  66 '--unreachable' flag it will also print out objects that exist but
  67 that aren't readable from any of the specified head nodes.
  68
  69 So for example
  70
  71         git-fsck-objects --unreachable HEAD $(cat .git/refs/heads/*)
  72
  73 will do quite a _lot_ of verification on the tree. There are a few
  74 extra validity tests to be added (make sure that tree objects are
  75 sorted properly etc), but on the whole if "git-fsck-objects" is happy, you
  76 do have a valid tree.
  77
  78 Any corrupt objects you will have to find in backups or other archives
  79 (ie you can just remove them and do an "rsync" with some other site in
  80 the hopes that somebody else has the object you have corrupted).
  81
  82 Of course, "valid tree" doesn't mean that it wasn't generated by some
  83 evil person, and the end result might be crap. git is a revision
  84 tracking system, not a quality assurance system ;)
  85
  86 Extracted Diagnostics
  87 ---------------------
  88
  89 expect dangling commits - potential heads - due to lack of head information::
  90         You haven't specified any nodes as heads so it won't be
  91         possible to differentiate between un-parented commits and
  92         root nodes.
  93
  94 missing sha1 directory '<dir>'::
  95         The directory holding the sha1 objects is missing.
  96
  97 unreachable <type> <object>::
  98         The <type> object <object>, isn't actually referred to directly
  99         or indirectly in any of the trees or commits seen. This can
 100         mean that there's another root node that you're not specifying
 101         or that the tree is corrupt. If you haven't missed a root node
 102         then you might as well delete unreachable nodes since they
 103         can't be used.
 104
 105 missing <type> <object>::
 106         The <type> object <object>, is referred to but isn't present in
 107         the database.
 108
 109 dangling <type> <object>::
 110         The <type> object <object>, is present in the database but never
 111         'directly' used. A dangling commit could be a root node.
 112
 113 warning: git-fsck-objects: tree <tree> has full pathnames in it::
 114         And it shouldn't...
 115
 116 sha1 mismatch <object>::
 117         The database has an object who's sha1 doesn't match the
 118         database value.
 119         This indicates a serious data integrity problem.
 120
 121 Environment Variables
 122 ---------------------
 123
 124 GIT_OBJECT_DIRECTORY::
 125         used to specify the object database root (usually $GIT_DIR/objects)
 126
 127 GIT_INDEX_FILE::
 128         used to specify the index file of the index
 129
 130 GIT_ALTERNATE_OBJECT_DIRECTORIES::
 131         used to specify additional object database roots (usually unset)
 132
 133 Author
 134 ------
 135 Written by Linus Torvalds <torvalds@osdl.org>
 136
 137 Documentation
 138 --------------
 139 Documentation by David Greaves, Junio C Hamano and the git-list <git@vger.kernel.org>.
 140
 141 GIT
 142 ---
 143 Part of the gitlink:git[7] suite
 144