1git-fsck-objects(1) 2=================== 3 4NAME 5---- 6git-fsck-objects - Verifies the connectivity and validity of the objects in the database 7 8 9SYNOPSIS 10-------- 11'git-fsck-objects' [--tags] [--root] [--unreachable] [--cache] [--standalone | --full] [--strict] [<object>*] 12 13DESCRIPTION 14----------- 15Verifies the connectivity and validity of the objects in the database. 16 17OPTIONS 18------- 19<object>:: 20 An object to treat as the head of an unreachability trace. 21+ 22If no objects are given, git-fsck-objects defaults to using the 23index 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 cache 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 63It tests SHA1 and general object sanity, and it does full tracking of 64the resulting reachability and everything else. It prints out any 65corruption it finds (missing or bad objects), and if you use the 66'--unreachable' flag it will also print out objects that exist but 67that aren't readable from any of the specified head nodes. 68 69So for example 70 71 git-fsck-objects --unreachable $(cat .git/HEAD .git/refs/heads/*) 72 73will do quite a _lot_ of verification on the tree. There are a few 74extra validity tests to be added (make sure that tree objects are 75sorted properly etc), but on the whole if "git-fsck-objects" is happy, you 76do have a valid tree. 77 78Any 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 80the hopes that somebody else has the object you have corrupted). 81 82Of course, "valid tree" doesn't mean that it wasn't generated by some 83evil person, and the end result might be crap. git is a revision 84tracking system, not a quality assurance system ;) 85 86Extracted Diagnostics 87--------------------- 88 89expect 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 94missing sha1 directory '<dir>':: 95 The directory holding the sha1 objects is missing. 96 97unreachable <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 105missing <type> <object>:: 106 The <type> object <object>, is referred to but isn't present in 107 the database. 108 109dangling <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 113warning: git-fsck-objects: tree <tree> has full pathnames in it:: 114 And it shouldn't... 115 116sha1 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 121Environment Variables 122--------------------- 123 124GIT_OBJECT_DIRECTORY:: 125 used to specify the object database root (usually $GIT_DIR/objects) 126 127GIT_INDEX_FILE:: 128 used to specify the index file of the cache 129 130GIT_ALTERNATE_OBJECT_DIRECTORIES:: 131 used to specify additional object database roots (usually unset) 132 133Author 134------ 135Written by Linus Torvalds <torvalds@osdl.org> 136 137Documentation 138-------------- 139Documentation by David Greaves, Junio C Hamano and the git-list <git@vger.kernel.org>. 140 141GIT 142--- 143Part of the gitlink:git[7] suite 144