[PATCH] Add cheap local clone '-s' flag to git-clone-script
From: Junio C Hamano <hidden>
Date: 2016-06-15 22:42:04
Subsystem:
the rest · Maintainer:
Linus Torvalds
Using the $GIT_OBJECT_DIRECTORY/info/alternates mechanism,
create a new repository that borrows objects from the original
repository when --shared flag is given in addition to --local.
It is worth pointing out that the "cloned" repository depends on
the original repository, so this should be used only when you
can reasonably trust that the original repository would not
disappear without your knowing.
Signed-off-by: Junio C Hamano <redacted>
---
This depends on the "Alternate object pool mechanism" patch I
sent out earlier, with a change suggested by Pasky to use
"$GIT_OBJECT_DIRECTORY/info/alternates" as the file name
instead of "info/alt".
This approach has the same danger as symlinking .git/objects
directory to the original repository that cg-clone mentions
about its '-l' option, but it is safer and easier to use in
multi-user environment. Objects newly created in the cloned
repository go to the primary object pool of it, not the
object pool of the original repository.
git-clone-script | 45 ++++++++++++++++++++++++++++-----------------
1 files changed, 28 insertions(+), 17 deletions(-)
ffdb36832dd755e65b9adfb68fa6b4a137176bc5diff --git a/git-clone-script b/git-clone-script
--- a/git-clone-script
+++ b/git-clone-script@@ -6,7 +6,7 @@ # Clone a repository into a different directory that does not yet exist. usage() { - echo >&2 "* git clone [-l] [-q] [-u <upload-pack>] <repo> <dir>" + echo >&2 "* git clone [-l [-s]] [-q] [-u <upload-pack>] <repo> <dir>" exit 1 }
@@ -16,11 +16,14 @@ get_repo_base() { quiet= use_local=no +local_shared=no upload_pack= while case "$#,$1" in 0,*) break ;; *,-l|*,--l|*,--lo|*,--loc|*,--loca|*,--local) use_local=yes ;; + *,-s|*,--s|*,--sh|*,--sha|*,--shar|*,--share|*,--shared) + local_shared=yes ;; *,-q|*,--quiet) quiet=-q ;; 1,-u|1,--upload-pack) usage ;; *,-u|*,--upload-pack)
@@ -57,22 +60,30 @@ yes,yes) exit 1 } - # See if we can hardlink and drop "l" if not. - sample_file=$(cd "$repo" && \ - find objects -type f -print | sed -e 1q) - - # objects directory should not be empty since we are cloning! - test -f "$repo/$sample_file" || exit - - l= - if ln "$repo/$sample_file" "$D/.git/objects/sample" 2>/dev/null - then - l=l - fi && - rm -f "$D/.git/objects/sample" && - cd "$repo" && - find objects -type f -print | - cpio -puamd$l "$D/.git/" || exit 1 + case "$local_shared" in + no) + # See if we can hardlink and drop "l" if not. + sample_file=$(cd "$repo" && \ + find objects -type f -print | sed -e 1q) + + # objects directory should not be empty since we are cloning! + test -f "$repo/$sample_file" || exit + + l= + if ln "$repo/$sample_file" "$D/.git/objects/sample" 2>/dev/null + then + l=l + fi && + rm -f "$D/.git/objects/sample" && + cd "$repo" && + find objects -type f -print | + cpio -puamd$l "$D/.git/" || exit 1 + ;; + yes) + mkdir -p "$D/.git/objects/info" + echo "$repo/objects" >"$D/.git/objects/info/alternates" + ;; + esac # Make a duplicate of refs and HEAD pointer HEAD=