From fa3a0c94dc88567b513e58835e5915f87da40af9 Mon Sep 17 00:00:00 2001 From: "Shawn O. Pearce" Date: Wed, 11 Feb 2009 10:15:30 -0800 Subject: [PATCH 1/3] Clear the delta base cache if a pack is rebuilt There is some risk that re-opening a regenerated pack file with different offsets could leave stale entries within the delta base cache that could be matched up against other objects using the same "struct packed_git*" and pack offset. Throwing away the entire delta base cache in this case is safer, as we don't have to worry about a recycled "struct packed_git*" matching to the wrong base object, resulting in delta apply errors while unpacking an object. Suggested-by: Daniel Barkalow Signed-off-by: Shawn O. Pearce Signed-off-by: Junio C Hamano --- sha1_file.c | 1 + 1 file changed, 1 insertion(+) diff --git a/sha1_file.c b/sha1_file.c index cbcae24d28..bea958ec81 100644 --- a/sha1_file.c +++ b/sha1_file.c @@ -676,6 +676,7 @@ void free_pack_by_name(const char *pack_name) while (*pp) { p = *pp; if (strcmp(pack_name, p->pack_name) == 0) { + clear_delta_base_cache(); close_pack_windows(p); if (p->pack_fd != -1) close(p->pack_fd); From 784f8affe4dfc8ceec93803d6c22b4b8467a4642 Mon Sep 17 00:00:00 2001 From: Elijah Newren Date: Tue, 10 Feb 2009 23:03:53 -0700 Subject: [PATCH 2/3] fast-export: ensure we traverse commits in topological order fast-export will only list as parents those commits which have already been traversed (making it appear as if merges have been squashed if not all parents have been traversed). To avoid this silent squashing of merge commits, we request commits in topological order. Signed-off-by: Elijah Newren Acked-by: Johannes Schindelin Signed-off-by: Junio C Hamano --- builtin-fast-export.c | 1 + 1 file changed, 1 insertion(+) diff --git a/builtin-fast-export.c b/builtin-fast-export.c index 838633808c..cdb7df5efe 100644 --- a/builtin-fast-export.c +++ b/builtin-fast-export.c @@ -511,6 +511,7 @@ int cmd_fast_export(int argc, const char **argv, const char *prefix) get_tags_and_duplicates(&revs.pending, &extra_refs); + revs.topo_order = 1; if (prepare_revision_walk(&revs)) die("revision walk setup failed"); revs.diffopt.format_callback = show_filemodify; From 3e6b1d0abcd58f0b2b106212ce0a0e07a6de342f Mon Sep 17 00:00:00 2001 From: Junio C Hamano Date: Tue, 10 Feb 2009 12:16:31 -0800 Subject: [PATCH 3/3] Make repack less likely to corrupt repository Some platforms refuse to rename a file that is open. When repacking an already packed repository without adding any new object, the resulting pack will contain the same set of objects as an existing pack, and on such platforms, a newly created packfile cannot replace the existing one. The logic detected this issue but did not try hard enough to recover from it. Especially because the files that needs renaming come in pairs, there potentially are different failure modes that one can be renamed but the others cannot. Asking manual recovery to end users were error prone. This patch tries to make it more robust by first making sure all the existing files that need to be renamed have been renamed before continuing, and attempts to roll back if some failed to rename. This is based on an initial patch by Robin Rosenberg. Signed-off-by: Junio C Hamano --- git-repack.sh | 87 +++++++++++++++++++++++++++++++++++++++------------ 1 file changed, 67 insertions(+), 20 deletions(-) diff --git a/git-repack.sh b/git-repack.sh index 458a497af8..be6db5e805 100755 --- a/git-repack.sh +++ b/git-repack.sh @@ -88,32 +88,79 @@ if [ -z "$names" ]; then echo Nothing new to pack. fi fi -for name in $names ; do - fullbases="$fullbases pack-$name" - chmod a-w "$PACKTMP-$name.pack" - chmod a-w "$PACKTMP-$name.idx" - mkdir -p "$PACKDIR" || exit +# Ok we have prepared all new packfiles. +mkdir -p "$PACKDIR" || exit + +# First see if there are packs of the same name and if so +# if we can move them out of the way (this can happen if we +# repacked immediately after packing fully. +rollback= +failed= +for name in $names +do for sfx in pack idx do - if test -f "$PACKDIR/pack-$name.$sfx" - then - mv -f "$PACKDIR/pack-$name.$sfx" \ - "$PACKDIR/old-pack-$name.$sfx" - fi - done && + file=pack-$name.$sfx + test -f "$PACKDIR/$file" || continue + rm -f "$PACKDIR/old-$file" && + mv "$PACKDIR/$file" "$PACKDIR/old-$file" || { + failed=t + break + } + rollback="$rollback $file" + done + test -z "$failed" || break +done + +# If renaming failed for any of them, roll the ones we have +# already renamed back to their original names. +if test -n "$failed" +then + rollback_failure= + for file in $rollback + do + mv "$PACKDIR/old-$file" "$PACKDIR/$file" || + rollback_failure="$rollback_failure $file" + done + if test -n "$rollback_failure" + then + echo >&2 "WARNING: Some packs in use have been renamed by" + echo >&2 "WARNING: prefixing old- to their name, in order to" + echo >&2 "WARNING: replace them with the new version of the" + echo >&2 "WARNING: file. But the operation failed, and" + echo >&2 "WARNING: attempt to rename them back to their" + echo >&2 "WARNING: original names also failed." + echo >&2 "WARNING: Please rename them in $PACKDIR manually:" + for file in $rollback_failure + do + echo >&2 "WARNING: old-$file -> $file" + done + fi + exit 1 +fi + +# Now the ones with the same name are out of the way... +fullbases= +for name in $names +do + fullbases="$fullbases pack-$name" + chmod a-w "$PACKTMP-$name.pack" + chmod a-w "$PACKTMP-$name.idx" mv -f "$PACKTMP-$name.pack" "$PACKDIR/pack-$name.pack" && - mv -f "$PACKTMP-$name.idx" "$PACKDIR/pack-$name.idx" && - test -f "$PACKDIR/pack-$name.pack" && - test -f "$PACKDIR/pack-$name.idx" || { - echo >&2 "Couldn't replace the existing pack with updated one." - echo >&2 "The original set of packs have been saved as" - echo >&2 "old-pack-$name.{pack,idx} in $PACKDIR." - exit 1 - } - rm -f "$PACKDIR/old-pack-$name.pack" "$PACKDIR/old-pack-$name.idx" + mv -f "$PACKTMP-$name.idx" "$PACKDIR/pack-$name.idx" || + exit +done + +# Remove the "old-" files +for name in $names +do + rm -f "$PACKDIR/old-pack-$name.idx" + rm -f "$PACKDIR/old-pack-$name.pack" done +# End of pack replacement. + if test "$remove_redundant" = t then # We know $existing are all redundant.