From ad491366de6c883cd04539cb86db31049201dfbd Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?Nguy=E1=BB=85n=20Th=C3=A1i=20Ng=E1=BB=8Dc=20Duy?= Date: Thu, 5 Dec 2013 20:02:32 +0700 Subject: make the sender advertise shallow commits to the receiver MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit If either receive-pack or upload-pack is called on a shallow repository, shallow commits (*) will be sent after the ref advertisement (but before the packet flush), so that the receiver has the full "shape" of the sender's commit graph. This will be needed for the receiver to update its .git/shallow if necessary. This breaks the protocol for all clients trying to push to a shallow repo, or fetch from one. Which is basically the same end result as today's "is_repository_shallow() && die()" in receive-pack and upload-pack. New clients will be made aware of shallow upstream and can make use of this information. The sender must send all shallow commits that are sent in the following pack. It may send more shallow commits than necessary. upload-pack for example may choose to advertise no shallow commits if it knows in advance that the pack it's going to send contains no shallow commits. But upload-pack is the server, so we choose the cheaper way, send full .git/shallow and let the client deal with it. Smart HTTP is not affected by this patch. Shallow support on smart-http comes later separately. (*) A shallow commit is a commit that terminates the revision walker. It is usually put in .git/shallow in order to keep the revision walker from going out of bound because there is no guarantee that objects behind this commit is available. Signed-off-by: Nguyễn Thái Ngọc Duy Signed-off-by: Junio C Hamano diff --git a/Documentation/technical/pack-protocol.txt b/Documentation/technical/pack-protocol.txt index b898e97..eb8edd1 100644 --- a/Documentation/technical/pack-protocol.txt +++ b/Documentation/technical/pack-protocol.txt @@ -161,6 +161,7 @@ MUST peel the ref if it's an annotated tag. ---- advertised-refs = (no-refs / list-of-refs) + *shallow flush-pkt no-refs = PKT-LINE(zero-id SP "capabilities^{}" @@ -174,6 +175,8 @@ MUST peel the ref if it's an annotated tag. other-tip = obj-id SP refname LF other-peeled = obj-id SP refname "^{}" LF + shallow = PKT-LINE("shallow" SP obj-id) + capability-list = capability *(SP capability) capability = 1*(LC_ALPHA / DIGIT / "-" / "_") LC_ALPHA = %x61-7A diff --git a/builtin/receive-pack.c b/builtin/receive-pack.c index 67ce1ef..cc8c34f 100644 --- a/builtin/receive-pack.c +++ b/builtin/receive-pack.c @@ -178,6 +178,8 @@ static void write_head_info(void) if (!sent_capabilities) show_ref("capabilities^{}", null_sha1); + advertise_shallow_grafts(1); + /* EOF */ packet_flush(1); } @@ -998,7 +1000,7 @@ int cmd_receive_pack(int argc, const char **argv, const char *prefix) if (!enter_repo(dir, 0)) die("'%s' does not appear to be a git repository", dir); - if (is_repository_shallow()) + if (is_repository_shallow() && stateless_rpc) die("attempt to push into a shallow repository"); git_config(receive_pack_config, NULL); diff --git a/commit.h b/commit.h index bd841f4..a879526 100644 --- a/commit.h +++ b/commit.h @@ -205,6 +205,7 @@ extern int write_shallow_commits(struct strbuf *out, int use_pack_protocol); extern void setup_alternate_shallow(struct lock_file *shallow_lock, const char **alternate_shallow_file); extern char *setup_temporary_shallow(void); +extern void advertise_shallow_grafts(int); int is_descendant_of(struct commit *, struct commit_list *); int in_merge_bases(struct commit *, struct commit *); diff --git a/shallow.c b/shallow.c index cdf37d6..f2c04b2 100644 --- a/shallow.c +++ b/shallow.c @@ -220,3 +220,18 @@ void setup_alternate_shallow(struct lock_file *shallow_lock, *alternate_shallow_file = ""; strbuf_release(&sb); } + +static int advertise_shallow_grafts_cb(const struct commit_graft *graft, void *cb) +{ + int fd = *(int *)cb; + if (graft->nr_parent == -1) + packet_write(fd, "shallow %s\n", sha1_to_hex(graft->sha1)); + return 0; +} + +void advertise_shallow_grafts(int fd) +{ + if (!is_repository_shallow()) + return; + for_each_commit_graft(advertise_shallow_grafts_cb, &fd); +} diff --git a/upload-pack.c b/upload-pack.c index c989a73..38b2a29 100644 --- a/upload-pack.c +++ b/upload-pack.c @@ -758,6 +758,7 @@ static void upload_pack(void) reset_timeout(); head_ref_namespaced(send_ref, &symref); for_each_namespaced_ref(send_ref, &symref); + advertise_shallow_grafts(1); packet_flush(1); } else { head_ref_namespaced(mark_our_ref, NULL); @@ -835,8 +836,9 @@ int main(int argc, char **argv) if (!enter_repo(dir, strict)) die("'%s' does not appear to be a git repository", dir); - if (is_repository_shallow()) - die("attempt to fetch/clone from a shallow repository"); + if (is_repository_shallow() && stateless_rpc) + die("attempt to push into a shallow repository"); + git_config(upload_pack_config, NULL); upload_pack(); return 0; -- cgit v0.10.2-6-g49f6