1git-fsck(1) 2=========== 3 4NAME 5---- 6git-fsck - Verifies the connectivity and validity of the objects in the database 7 8 9SYNOPSIS 10-------- 11[verse] 12'git-fsck' [--tags] [--root] [--unreachable] [--cache] 13 [--full] [--strict] [<object>*] 14 15DESCRIPTION 16----------- 17Verifies the connectivity and validity of the objects in the database. 18 19OPTIONS 20------- 21<object>:: 22 An object to treat as the head of an unreachability trace. 23+ 24If no objects are given, git-fsck defaults to using the 25index 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--full:: 42 Check not just objects in GIT_OBJECT_DIRECTORY 43 ($GIT_DIR/objects), but also the ones found in alternate 44 object pools listed in GIT_ALTERNATE_OBJECT_DIRECTORIES 45 or $GIT_DIR/objects/info/alternates, 46 and in packed git archives found in $GIT_DIR/objects/pack 47 and corresponding pack subdirectories in alternate 48 object pools. 49 50--strict:: 51 Enable more strict checking, namely to catch a file mode 52 recorded with g+w bit set, which was created by older 53 versions of git. Existing repositories, including the 54 Linux kernel, git itself, and sparse repository have old 55 objects that triggers this check, but it is recommended 56 to check new projects with this flag. 57 58It tests SHA1 and general object sanity, and it does full tracking of 59the resulting reachability and everything else. It prints out any 60corruption it finds (missing or bad objects), and if you use the 61'--unreachable' flag it will also print out objects that exist but 62that aren't readable from any of the specified head nodes. 63 64So for example 65 66 git-fsck --unreachable HEAD $(cat .git/refs/heads/*) 67 68will do quite a _lot_ of verification on the tree. There are a few 69extra validity tests to be added (make sure that tree objects are 70sorted properly etc), but on the whole if "git-fsck" is happy, you 71do have a valid tree. 72 73Any corrupt objects you will have to find in backups or other archives 74(i.e., you can just remove them and do an "rsync" with some other site in 75the hopes that somebody else has the object you have corrupted). 76 77Of course, "valid tree" doesn't mean that it wasn't generated by some 78evil person, and the end result might be crap. git is a revision 79tracking system, not a quality assurance system ;) 80 81Extracted Diagnostics 82--------------------- 83 84expect dangling commits - potential heads - due to lack of head information:: 85 You haven't specified any nodes as heads so it won't be 86 possible to differentiate between un-parented commits and 87 root nodes. 88 89missing sha1 directory '<dir>':: 90 The directory holding the sha1 objects is missing. 91 92unreachable <type> <object>:: 93 The <type> object <object>, isn't actually referred to directly 94 or indirectly in any of the trees or commits seen. This can 95 mean that there's another root node that you're not specifying 96 or that the tree is corrupt. If you haven't missed a root node 97 then you might as well delete unreachable nodes since they 98 can't be used. 99 100missing <type> <object>:: 101 The <type> object <object>, is referred to but isn't present in 102 the database. 103 104dangling <type> <object>:: 105 The <type> object <object>, is present in the database but never 106 'directly' used. A dangling commit could be a root node. 107 108warning: git-fsck: tree <tree> has full pathnames in it:: 109 And it shouldn't... 110 111sha1 mismatch <object>:: 112 The database has an object who's sha1 doesn't match the 113 database value. 114 This indicates a serious data integrity problem. 115 116Environment Variables 117--------------------- 118 119GIT_OBJECT_DIRECTORY:: 120 used to specify the object database root (usually $GIT_DIR/objects) 121 122GIT_INDEX_FILE:: 123 used to specify the index file of the index 124 125GIT_ALTERNATE_OBJECT_DIRECTORIES:: 126 used to specify additional object database roots (usually unset) 127 128Author 129------ 130Written by Linus Torvalds <torvalds@osdl.org> 131 132Documentation 133-------------- 134Documentation by David Greaves, Junio C Hamano and the git-list <git@vger.kernel.org>. 135 136GIT 137--- 138Part of the gitlink:git[7] suite 139