From 59e1205d167c9acc17114a2f96425325470b1db8 Mon Sep 17 00:00:00 2001 From: Jonathan Tan Date: Fri, 5 Feb 2021 12:48:47 -0800 Subject: [PATCH 1/3] ls-refs: report unborn targets of symrefs When cloning, we choose the default branch based on the remote HEAD. But if there is no remote HEAD reported (which could happen if the target of the remote HEAD is unborn), we'll fall back to using our local init.defaultBranch. Traditionally this hasn't been a big deal, because most repos used "master" as the default. But these days it is likely to cause confusion if the server and client implementations choose different values (e.g., if the remote started with "main", we may choose "master" locally, create commits there, and then the user is surprised when they push to "master" and not "main"). To solve this, the remote needs to communicate the target of the HEAD symref, even if it is unborn, and "git clone" needs to use this information. Currently, symrefs that have unborn targets (such as in this case) are not communicated by the protocol. Teach Git to advertise and support the "unborn" feature in "ls-refs" (by default, this is advertised, but server administrators may turn this off through the lsrefs.unborn config). This feature indicates that "ls-refs" supports the "unborn" argument; when it is specified, "ls-refs" will send the HEAD symref with the name of its unborn target. This change is only for protocol v2. A similar change for protocol v0 would require independent protocol design (there being no analogous position to signal support for "unborn") and client-side plumbing of the data required, so the scope of this patch set is limited to protocol v2. The client side will be updated to use this in a subsequent commit. Signed-off-by: Jonathan Tan Signed-off-by: Junio C Hamano --- Documentation/config.txt | 2 + Documentation/config/lsrefs.txt | 9 +++ Documentation/technical/protocol-v2.txt | 11 +++- ls-refs.c | 74 ++++++++++++++++++++++++- ls-refs.h | 1 + serve.c | 2 +- t/t5701-git-serve.sh | 2 +- 7 files changed, 95 insertions(+), 6 deletions(-) create mode 100644 Documentation/config/lsrefs.txt diff --git a/Documentation/config.txt b/Documentation/config.txt index 6ba50b1104a..d08e83a1482 100644 --- a/Documentation/config.txt +++ b/Documentation/config.txt @@ -398,6 +398,8 @@ include::config/interactive.txt[] include::config/log.txt[] +include::config/lsrefs.txt[] + include::config/mailinfo.txt[] include::config/mailmap.txt[] diff --git a/Documentation/config/lsrefs.txt b/Documentation/config/lsrefs.txt new file mode 100644 index 00000000000..adeda0f24d3 --- /dev/null +++ b/Documentation/config/lsrefs.txt @@ -0,0 +1,9 @@ +lsrefs.unborn:: + May be "advertise" (the default), "allow", or "ignore". If "advertise", + the server will respond to the client sending "unborn" (as described in + protocol-v2.txt) and will advertise support for this feature during the + protocol v2 capability advertisement. "allow" is the same as + "advertise" except that the server will not advertise support for this + feature; this is useful for load-balanced servers that cannot be + updated atomically (for example), since the administrator could + configure "allow", then after a delay, configure "advertise". diff --git a/Documentation/technical/protocol-v2.txt b/Documentation/technical/protocol-v2.txt index 85daeb5d9e7..f772d90eaf9 100644 --- a/Documentation/technical/protocol-v2.txt +++ b/Documentation/technical/protocol-v2.txt @@ -192,11 +192,20 @@ ls-refs takes in the following arguments: When specified, only references having a prefix matching one of the provided prefixes are displayed. +If the 'unborn' feature is advertised the following argument can be +included in the client's request. + + unborn + The server will send information about HEAD even if it is a symref + pointing to an unborn branch in the form "unborn HEAD + symref-target:". + The output of ls-refs is as follows: output = *ref flush-pkt - ref = PKT-LINE(obj-id SP refname *(SP ref-attribute) LF) + obj-id-or-unborn = (obj-id | "unborn") + ref = PKT-LINE(obj-id-or-unborn SP refname *(SP ref-attribute) LF) ref-attribute = (symref | peeled) symref = "symref-target:" symref-target peeled = "peeled:" obj-id diff --git a/ls-refs.c b/ls-refs.c index a1e0b473e44..32deb7be448 100644 --- a/ls-refs.c +++ b/ls-refs.c @@ -7,6 +7,39 @@ #include "pkt-line.h" #include "config.h" +static int config_read; +static int advertise_unborn; +static int allow_unborn; + +static void ensure_config_read(void) +{ + const char *str = NULL; + + if (config_read) + return; + + if (repo_config_get_string_tmp(the_repository, "lsrefs.unborn", &str)) { + /* + * If there is no such config, advertise and allow it by + * default. + */ + advertise_unborn = 1; + allow_unborn = 1; + } else { + if (!strcmp(str, "advertise")) { + advertise_unborn = 1; + allow_unborn = 1; + } else if (!strcmp(str, "allow")) { + allow_unborn = 1; + } else if (!strcmp(str, "ignore")) { + /* do nothing */ + } else { + die(_("invalid value '%s' for lsrefs.unborn"), str); + } + } + config_read = 1; +} + /* * Check if one of the prefixes is a prefix of the ref. * If no prefixes were provided, all refs match. @@ -32,6 +65,7 @@ struct ls_refs_data { unsigned peel; unsigned symrefs; struct strvec prefixes; + unsigned unborn : 1; }; static int send_ref(const char *refname, const struct object_id *oid, @@ -47,7 +81,10 @@ static int send_ref(const char *refname, const struct object_id *oid, if (!ref_match(&data->prefixes, refname_nons)) return 0; - strbuf_addf(&refline, "%s %s", oid_to_hex(oid), refname_nons); + if (oid) + strbuf_addf(&refline, "%s %s", oid_to_hex(oid), refname_nons); + else + strbuf_addf(&refline, "unborn %s", refname_nons); if (data->symrefs && flag & REF_ISSYMREF) { struct object_id unused; const char *symref_target = resolve_ref_unsafe(refname, 0, @@ -61,7 +98,7 @@ static int send_ref(const char *refname, const struct object_id *oid, strip_namespace(symref_target)); } - if (data->peel) { + if (data->peel && oid) { struct object_id peeled; if (!peel_ref(refname, &peeled)) strbuf_addf(&refline, " peeled:%s", oid_to_hex(&peeled)); @@ -74,6 +111,23 @@ static int send_ref(const char *refname, const struct object_id *oid, return 0; } +static void send_possibly_unborn_head(struct ls_refs_data *data) +{ + struct strbuf namespaced = STRBUF_INIT; + struct object_id oid; + int flag; + int oid_is_null; + + strbuf_addf(&namespaced, "%sHEAD", get_git_namespace()); + if (!resolve_ref_unsafe(namespaced.buf, 0, &oid, &flag)) + return; /* bad ref */ + oid_is_null = is_null_oid(&oid); + if (!oid_is_null || + (data->unborn && data->symrefs && (flag & REF_ISSYMREF))) + send_ref(namespaced.buf, oid_is_null ? NULL : &oid, flag, data); + strbuf_release(&namespaced); +} + static int ls_refs_config(const char *var, const char *value, void *data) { /* @@ -91,6 +145,7 @@ int ls_refs(struct repository *r, struct strvec *keys, memset(&data, 0, sizeof(data)); + ensure_config_read(); git_config(ls_refs_config, NULL); while (packet_reader_read(request) == PACKET_READ_NORMAL) { @@ -103,14 +158,27 @@ int ls_refs(struct repository *r, struct strvec *keys, data.symrefs = 1; else if (skip_prefix(arg, "ref-prefix ", &out)) strvec_push(&data.prefixes, out); + else if (!strcmp("unborn", arg)) + data.unborn = allow_unborn; } if (request->status != PACKET_READ_FLUSH) die(_("expected flush after ls-refs arguments")); - head_ref_namespaced(send_ref, &data); + send_possibly_unborn_head(&data); for_each_namespaced_ref(send_ref, &data); packet_flush(1); strvec_clear(&data.prefixes); return 0; } + +int ls_refs_advertise(struct repository *r, struct strbuf *value) +{ + if (value) { + ensure_config_read(); + if (advertise_unborn) + strbuf_addstr(value, "unborn"); + } + + return 1; +} diff --git a/ls-refs.h b/ls-refs.h index 7b33a7c6b81..a99e4be0bdd 100644 --- a/ls-refs.h +++ b/ls-refs.h @@ -6,5 +6,6 @@ struct strvec; struct packet_reader; int ls_refs(struct repository *r, struct strvec *keys, struct packet_reader *request); +int ls_refs_advertise(struct repository *r, struct strbuf *value); #endif /* LS_REFS_H */ diff --git a/serve.c b/serve.c index eec2fe6f294..ac20c727630 100644 --- a/serve.c +++ b/serve.c @@ -73,7 +73,7 @@ struct protocol_capability { static struct protocol_capability capabilities[] = { { "agent", agent_advertise, NULL }, - { "ls-refs", always_advertise, ls_refs }, + { "ls-refs", ls_refs_advertise, ls_refs }, { "fetch", upload_pack_advertise, upload_pack_v2 }, { "server-option", always_advertise, NULL }, { "object-format", object_format_advertise, NULL }, diff --git a/t/t5701-git-serve.sh b/t/t5701-git-serve.sh index a1f5fdc9fdc..df295041619 100755 --- a/t/t5701-git-serve.sh +++ b/t/t5701-git-serve.sh @@ -12,7 +12,7 @@ test_expect_success 'test capability advertisement' ' cat >expect <<-EOF && version 2 agent=git/$(git version | cut -d" " -f3) - ls-refs + ls-refs=unborn fetch=shallow server-option object-format=$(test_oid algo) From 39835409d10de2402c4b3e10dba20286989627d4 Mon Sep 17 00:00:00 2001 From: Jonathan Tan Date: Fri, 5 Feb 2021 12:48:48 -0800 Subject: [PATCH 2/3] connect, transport: encapsulate arg in struct In a future patch we plan to return the name of an unborn current branch from deep in the callchain to a caller via a new pointer parameter that points at a variable in the caller when the caller calls get_remote_refs() and transport_get_remote_refs(). In preparation for that, encapsulate the existing ref_prefixes parameter into a struct. The aforementioned unborn current branch will go into this new struct in the future patch. Signed-off-by: Jonathan Tan Signed-off-by: Junio C Hamano --- builtin/clone.c | 18 +++++++++++------- builtin/fetch-pack.c | 3 ++- builtin/fetch.c | 18 +++++++++++------- builtin/ls-remote.c | 9 +++++---- connect.c | 4 +++- remote.h | 4 +++- transport-helper.c | 5 +++-- transport-internal.h | 10 ++-------- transport.c | 23 ++++++++++++----------- transport.h | 21 ++++++++++++++------- 10 files changed, 66 insertions(+), 49 deletions(-) diff --git a/builtin/clone.c b/builtin/clone.c index a5630337e4e..211d4f54b09 100644 --- a/builtin/clone.c +++ b/builtin/clone.c @@ -979,7 +979,8 @@ int cmd_clone(int argc, const char **argv, const char *prefix) int err = 0, complete_refs_before_fetch = 1; int submodule_progress; - struct strvec ref_prefixes = STRVEC_INIT; + struct transport_ls_refs_options transport_ls_refs_options = + TRANSPORT_LS_REFS_OPTIONS_INIT; packet_trace_identity("clone"); @@ -1257,14 +1258,17 @@ int cmd_clone(int argc, const char **argv, const char *prefix) transport->smart_options->check_self_contained_and_connected = 1; - strvec_push(&ref_prefixes, "HEAD"); - refspec_ref_prefixes(&remote->fetch, &ref_prefixes); + strvec_push(&transport_ls_refs_options.ref_prefixes, "HEAD"); + refspec_ref_prefixes(&remote->fetch, + &transport_ls_refs_options.ref_prefixes); if (option_branch) - expand_ref_prefix(&ref_prefixes, option_branch); + expand_ref_prefix(&transport_ls_refs_options.ref_prefixes, + option_branch); if (!option_no_tags) - strvec_push(&ref_prefixes, "refs/tags/"); + strvec_push(&transport_ls_refs_options.ref_prefixes, + "refs/tags/"); - refs = transport_get_remote_refs(transport, &ref_prefixes); + refs = transport_get_remote_refs(transport, &transport_ls_refs_options); if (refs) { int hash_algo = hash_algo_by_ptr(transport_get_hash_algo(transport)); @@ -1380,6 +1384,6 @@ int cmd_clone(int argc, const char **argv, const char *prefix) strbuf_release(&key); junk_mode = JUNK_LEAVE_ALL; - strvec_clear(&ref_prefixes); + strvec_clear(&transport_ls_refs_options.ref_prefixes); return err; } diff --git a/builtin/fetch-pack.c b/builtin/fetch-pack.c index 58b7c1fbdc4..c2d96f4c89a 100644 --- a/builtin/fetch-pack.c +++ b/builtin/fetch-pack.c @@ -220,7 +220,8 @@ int cmd_fetch_pack(int argc, const char **argv, const char *prefix) version = discover_version(&reader); switch (version) { case protocol_v2: - get_remote_refs(fd[1], &reader, &ref, 0, NULL, NULL, args.stateless_rpc); + get_remote_refs(fd[1], &reader, &ref, 0, NULL, NULL, + args.stateless_rpc); break; case protocol_v1: case protocol_v0: diff --git a/builtin/fetch.c b/builtin/fetch.c index ecf85376050..837382ef4f0 100644 --- a/builtin/fetch.c +++ b/builtin/fetch.c @@ -1349,7 +1349,8 @@ static int do_fetch(struct transport *transport, int autotags = (transport->remote->fetch_tags == 1); int retcode = 0; const struct ref *remote_refs; - struct strvec ref_prefixes = STRVEC_INIT; + struct transport_ls_refs_options transport_ls_refs_options = + TRANSPORT_LS_REFS_OPTIONS_INIT; int must_list_refs = 1; if (tags == TAGS_DEFAULT) { @@ -1369,7 +1370,7 @@ static int do_fetch(struct transport *transport, if (rs->nr) { int i; - refspec_ref_prefixes(rs, &ref_prefixes); + refspec_ref_prefixes(rs, &transport_ls_refs_options.ref_prefixes); /* * We can avoid listing refs if all of them are exact @@ -1383,22 +1384,25 @@ static int do_fetch(struct transport *transport, } } } else if (transport->remote && transport->remote->fetch.nr) - refspec_ref_prefixes(&transport->remote->fetch, &ref_prefixes); + refspec_ref_prefixes(&transport->remote->fetch, + &transport_ls_refs_options.ref_prefixes); if (tags == TAGS_SET || tags == TAGS_DEFAULT) { must_list_refs = 1; - if (ref_prefixes.nr) - strvec_push(&ref_prefixes, "refs/tags/"); + if (transport_ls_refs_options.ref_prefixes.nr) + strvec_push(&transport_ls_refs_options.ref_prefixes, + "refs/tags/"); } if (must_list_refs) { trace2_region_enter("fetch", "remote_refs", the_repository); - remote_refs = transport_get_remote_refs(transport, &ref_prefixes); + remote_refs = transport_get_remote_refs(transport, + &transport_ls_refs_options); trace2_region_leave("fetch", "remote_refs", the_repository); } else remote_refs = NULL; - strvec_clear(&ref_prefixes); + strvec_clear(&transport_ls_refs_options.ref_prefixes); ref_map = get_ref_map(transport->remote, remote_refs, rs, tags, &autotags); diff --git a/builtin/ls-remote.c b/builtin/ls-remote.c index 092917eca29..ef604752a04 100644 --- a/builtin/ls-remote.c +++ b/builtin/ls-remote.c @@ -45,7 +45,8 @@ int cmd_ls_remote(int argc, const char **argv, const char *prefix) int show_symref_target = 0; const char *uploadpack = NULL; const char **pattern = NULL; - struct strvec ref_prefixes = STRVEC_INIT; + struct transport_ls_refs_options transport_options = + TRANSPORT_LS_REFS_OPTIONS_INIT; int i; struct string_list server_options = STRING_LIST_INIT_DUP; @@ -94,9 +95,9 @@ int cmd_ls_remote(int argc, const char **argv, const char *prefix) } if (flags & REF_TAGS) - strvec_push(&ref_prefixes, "refs/tags/"); + strvec_push(&transport_options.ref_prefixes, "refs/tags/"); if (flags & REF_HEADS) - strvec_push(&ref_prefixes, "refs/heads/"); + strvec_push(&transport_options.ref_prefixes, "refs/heads/"); remote = remote_get(dest); if (!remote) { @@ -118,7 +119,7 @@ int cmd_ls_remote(int argc, const char **argv, const char *prefix) if (server_options.nr) transport->server_options = &server_options; - ref = transport_get_remote_refs(transport, &ref_prefixes); + ref = transport_get_remote_refs(transport, &transport_options); if (ref) { int hash_algo = hash_algo_by_ptr(transport_get_hash_algo(transport)); repo_set_hash_algo(the_repository, hash_algo); diff --git a/connect.c b/connect.c index 8b8f56cf6d2..328c2792504 100644 --- a/connect.c +++ b/connect.c @@ -453,12 +453,14 @@ void check_stateless_delimiter(int stateless_rpc, struct ref **get_remote_refs(int fd_out, struct packet_reader *reader, struct ref **list, int for_push, - const struct strvec *ref_prefixes, + struct transport_ls_refs_options *transport_options, const struct string_list *server_options, int stateless_rpc) { int i; const char *hash_name; + struct strvec *ref_prefixes = transport_options ? + &transport_options->ref_prefixes : NULL; *list = NULL; if (server_supports_v2("ls-refs", 1)) diff --git a/remote.h b/remote.h index 3211abdf05c..4ae676a11b7 100644 --- a/remote.h +++ b/remote.h @@ -6,6 +6,8 @@ #include "hashmap.h" #include "refspec.h" +struct transport_ls_refs_options; + /** * The API gives access to the configuration related to remotes. It handles * all three configuration mechanisms historically and currently used by Git, @@ -196,7 +198,7 @@ struct ref **get_remote_heads(struct packet_reader *reader, /* Used for protocol v2 in order to retrieve refs from a remote */ struct ref **get_remote_refs(int fd_out, struct packet_reader *reader, struct ref **list, int for_push, - const struct strvec *ref_prefixes, + struct transport_ls_refs_options *transport_options, const struct string_list *server_options, int stateless_rpc); diff --git a/transport-helper.c b/transport-helper.c index 5f6e0b3bd87..49b7fb4dcb9 100644 --- a/transport-helper.c +++ b/transport-helper.c @@ -1162,13 +1162,14 @@ static int has_attribute(const char *attrs, const char *attr) } static struct ref *get_refs_list(struct transport *transport, int for_push, - const struct strvec *ref_prefixes) + struct transport_ls_refs_options *transport_options) { get_helper(transport); if (process_connect(transport, for_push)) { do_take_over(transport); - return transport->vtable->get_refs_list(transport, for_push, ref_prefixes); + return transport->vtable->get_refs_list(transport, for_push, + transport_options); } return get_refs_list_using_list(transport, for_push); diff --git a/transport-internal.h b/transport-internal.h index 27c9daffc47..b60f1ba9077 100644 --- a/transport-internal.h +++ b/transport-internal.h @@ -4,6 +4,7 @@ struct ref; struct transport; struct strvec; +struct transport_ls_refs_options; struct transport_vtable { /** @@ -18,19 +19,12 @@ struct transport_vtable { * the transport to try to share connections, for_push is a * hint as to whether the ultimate operation is a push or a fetch. * - * If communicating using protocol v2 a list of prefixes can be - * provided to be sent to the server to enable it to limit the ref - * advertisement. Since ref filtering is done on the server's end, and - * only when using protocol v2, this list will be ignored when not - * using protocol v2 meaning this function can return refs which don't - * match the provided ref_prefixes. - * * If the transport is able to determine the remote hash for * the ref without a huge amount of effort, it should store it * in the ref's old_sha1 field; otherwise it should be all 0. **/ struct ref *(*get_refs_list)(struct transport *transport, int for_push, - const struct strvec *ref_prefixes); + struct transport_ls_refs_options *transport_options); /** * Fetch the objects for the given refs. Note that this gets diff --git a/transport.c b/transport.c index 679a35e7c1b..b13fab5dc3b 100644 --- a/transport.c +++ b/transport.c @@ -127,7 +127,7 @@ struct bundle_transport_data { static struct ref *get_refs_from_bundle(struct transport *transport, int for_push, - const struct strvec *ref_prefixes) + struct transport_ls_refs_options *transport_options) { struct bundle_transport_data *data = transport->data; struct ref *result = NULL; @@ -280,7 +280,7 @@ static void die_if_server_options(struct transport *transport) * remote refs. */ static struct ref *handshake(struct transport *transport, int for_push, - const struct strvec *ref_prefixes, + struct transport_ls_refs_options *options, int must_list_refs) { struct git_transport_data *data = transport->data; @@ -303,7 +303,7 @@ static struct ref *handshake(struct transport *transport, int for_push, trace2_data_string("transfer", NULL, "server-sid", server_sid); if (must_list_refs) get_remote_refs(data->fd[1], &reader, &refs, for_push, - ref_prefixes, + options, transport->server_options, transport->stateless_rpc); break; @@ -334,9 +334,9 @@ static struct ref *handshake(struct transport *transport, int for_push, } static struct ref *get_refs_via_connect(struct transport *transport, int for_push, - const struct strvec *ref_prefixes) + struct transport_ls_refs_options *options) { - return handshake(transport, for_push, ref_prefixes, 1); + return handshake(transport, for_push, options, 1); } static int fetch_refs_via_pack(struct transport *transport, @@ -1252,19 +1252,20 @@ int transport_push(struct repository *r, int porcelain = flags & TRANSPORT_PUSH_PORCELAIN; int pretend = flags & TRANSPORT_PUSH_DRY_RUN; int push_ret, ret, err; - struct strvec ref_prefixes = STRVEC_INIT; + struct transport_ls_refs_options transport_options = + TRANSPORT_LS_REFS_OPTIONS_INIT; if (check_push_refs(local_refs, rs) < 0) return -1; - refspec_ref_prefixes(rs, &ref_prefixes); + refspec_ref_prefixes(rs, &transport_options.ref_prefixes); trace2_region_enter("transport_push", "get_refs_list", r); remote_refs = transport->vtable->get_refs_list(transport, 1, - &ref_prefixes); + &transport_options); trace2_region_leave("transport_push", "get_refs_list", r); - strvec_clear(&ref_prefixes); + strvec_clear(&transport_options.ref_prefixes); if (flags & TRANSPORT_PUSH_ALL) match_flags |= MATCH_REFS_ALL; @@ -1380,12 +1381,12 @@ int transport_push(struct repository *r, } const struct ref *transport_get_remote_refs(struct transport *transport, - const struct strvec *ref_prefixes) + struct transport_ls_refs_options *transport_options) { if (!transport->got_remote_refs) { transport->remote_refs = transport->vtable->get_refs_list(transport, 0, - ref_prefixes); + transport_options); transport->got_remote_refs = 1; } diff --git a/transport.h b/transport.h index 24558c027d6..1f5b60e4d31 100644 --- a/transport.h +++ b/transport.h @@ -233,17 +233,24 @@ int transport_push(struct repository *repo, struct refspec *rs, int flags, unsigned int * reject_reasons); +struct transport_ls_refs_options { + /* + * Optionally, a list of ref prefixes can be provided which can be sent + * to the server (when communicating using protocol v2) to enable it to + * limit the ref advertisement. Since ref filtering is done on the + * server's end (and only when using protocol v2), + * transport_get_remote_refs() could return refs which don't match the + * provided ref_prefixes. + */ + struct strvec ref_prefixes; +}; +#define TRANSPORT_LS_REFS_OPTIONS_INIT { STRVEC_INIT } + /* * Retrieve refs from a remote. - * - * Optionally a list of ref prefixes can be provided which can be sent to the - * server (when communicating using protocol v2) to enable it to limit the ref - * advertisement. Since ref filtering is done on the server's end (and only - * when using protocol v2), this can return refs which don't match the provided - * ref_prefixes. */ const struct ref *transport_get_remote_refs(struct transport *transport, - const struct strvec *ref_prefixes); + struct transport_ls_refs_options *transport_options); /* * Fetch the hash algorithm used by a remote. From 4f37d45706514a4b3d0259d26f719678a0cf3521 Mon Sep 17 00:00:00 2001 From: Jonathan Tan Date: Fri, 5 Feb 2021 12:48:49 -0800 Subject: [PATCH 3/3] clone: respect remote unborn HEAD Teach Git to use the "unborn" feature introduced in a previous patch as follows: Git will always send the "unborn" argument if it is supported by the server. During "git clone", if cloning an empty repository, Git will use the new information to determine the local branch to create. In all other cases, Git will ignore it. Signed-off-by: Jonathan Tan Signed-off-by: Junio C Hamano --- Documentation/config/init.txt | 2 +- builtin/clone.c | 16 ++++++++++++++-- connect.c | 28 ++++++++++++++++++++++++++-- t/t5606-clone-options.sh | 8 +++++--- t/t5702-protocol-v2.sh | 25 +++++++++++++++++++++++++ transport.h | 8 ++++++++ 6 files changed, 79 insertions(+), 8 deletions(-) diff --git a/Documentation/config/init.txt b/Documentation/config/init.txt index dc77f8c8446..79c79d66174 100644 --- a/Documentation/config/init.txt +++ b/Documentation/config/init.txt @@ -4,4 +4,4 @@ init.templateDir:: init.defaultBranch:: Allows overriding the default branch name e.g. when initializing - a new repository or when cloning an empty repository. + a new repository. diff --git a/builtin/clone.c b/builtin/clone.c index 211d4f54b09..09dcd97a2e7 100644 --- a/builtin/clone.c +++ b/builtin/clone.c @@ -1330,8 +1330,19 @@ int cmd_clone(int argc, const char **argv, const char *prefix) remote_head = NULL; option_no_checkout = 1; if (!option_bare) { - const char *branch = git_default_branch_name(); - char *ref = xstrfmt("refs/heads/%s", branch); + const char *branch; + char *ref; + + if (transport_ls_refs_options.unborn_head_target && + skip_prefix(transport_ls_refs_options.unborn_head_target, + "refs/heads/", &branch)) { + ref = transport_ls_refs_options.unborn_head_target; + transport_ls_refs_options.unborn_head_target = NULL; + create_symref("HEAD", ref, reflog_msg.buf); + } else { + branch = git_default_branch_name(); + ref = xstrfmt("refs/heads/%s", branch); + } install_branch_config(0, branch, remote_name, ref); free(ref); @@ -1385,5 +1396,6 @@ int cmd_clone(int argc, const char **argv, const char *prefix) junk_mode = JUNK_LEAVE_ALL; strvec_clear(&transport_ls_refs_options.ref_prefixes); + free(transport_ls_refs_options.unborn_head_target); return err; } diff --git a/connect.c b/connect.c index 328c2792504..879669df930 100644 --- a/connect.c +++ b/connect.c @@ -376,7 +376,8 @@ struct ref **get_remote_heads(struct packet_reader *reader, } /* Returns 1 when a valid ref has been added to `list`, 0 otherwise */ -static int process_ref_v2(struct packet_reader *reader, struct ref ***list) +static int process_ref_v2(struct packet_reader *reader, struct ref ***list, + char **unborn_head_target) { int ret = 1; int i = 0; @@ -397,6 +398,25 @@ static int process_ref_v2(struct packet_reader *reader, struct ref ***list) goto out; } + if (!strcmp("unborn", line_sections.items[i].string)) { + i++; + if (unborn_head_target && + !strcmp("HEAD", line_sections.items[i++].string)) { + /* + * Look for the symref target (if any). If found, + * return it to the caller. + */ + for (; i < line_sections.nr; i++) { + const char *arg = line_sections.items[i].string; + + if (skip_prefix(arg, "symref-target:", &arg)) { + *unborn_head_target = xstrdup(arg); + break; + } + } + } + goto out; + } if (parse_oid_hex_algop(line_sections.items[i++].string, &old_oid, &end, reader->hash_algo) || *end) { ret = 0; @@ -461,6 +481,8 @@ struct ref **get_remote_refs(int fd_out, struct packet_reader *reader, const char *hash_name; struct strvec *ref_prefixes = transport_options ? &transport_options->ref_prefixes : NULL; + char **unborn_head_target = transport_options ? + &transport_options->unborn_head_target : NULL; *list = NULL; if (server_supports_v2("ls-refs", 1)) @@ -490,6 +512,8 @@ struct ref **get_remote_refs(int fd_out, struct packet_reader *reader, if (!for_push) packet_write_fmt(fd_out, "peel\n"); packet_write_fmt(fd_out, "symrefs\n"); + if (server_supports_feature("ls-refs", "unborn", 0)) + packet_write_fmt(fd_out, "unborn\n"); for (i = 0; ref_prefixes && i < ref_prefixes->nr; i++) { packet_write_fmt(fd_out, "ref-prefix %s\n", ref_prefixes->v[i]); @@ -498,7 +522,7 @@ struct ref **get_remote_refs(int fd_out, struct packet_reader *reader, /* Process response from server */ while (packet_reader_read(reader) == PACKET_READ_NORMAL) { - if (!process_ref_v2(reader, &list)) + if (!process_ref_v2(reader, &list, unborn_head_target)) die(_("invalid ls-refs response: %s"), reader->line); } diff --git a/t/t5606-clone-options.sh b/t/t5606-clone-options.sh index 7f082fb23b6..ca6339a5fba 100755 --- a/t/t5606-clone-options.sh +++ b/t/t5606-clone-options.sh @@ -102,11 +102,13 @@ test_expect_success 'redirected clone -v does show progress' ' ' test_expect_success 'chooses correct default initial branch name' ' - git init --bare empty && + GIT_TEST_DEFAULT_INITIAL_BRANCH_NAME= \ + git -c init.defaultBranch=foo init --bare empty && + test_config -C empty lsrefs.unborn advertise && GIT_TEST_DEFAULT_INITIAL_BRANCH_NAME= \ git -c init.defaultBranch=up clone empty whats-up && - test refs/heads/up = $(git -C whats-up symbolic-ref HEAD) && - test refs/heads/up = $(git -C whats-up config branch.up.merge) + test refs/heads/foo = $(git -C whats-up symbolic-ref HEAD) && + test refs/heads/foo = $(git -C whats-up config branch.foo.merge) ' test_expect_success 'guesses initial branch name correctly' ' diff --git a/t/t5702-protocol-v2.sh b/t/t5702-protocol-v2.sh index 7d5b17909bb..b2ead93af97 100755 --- a/t/t5702-protocol-v2.sh +++ b/t/t5702-protocol-v2.sh @@ -209,6 +209,31 @@ test_expect_success 'clone with file:// using protocol v2' ' grep "ref-prefix refs/tags/" log ' +test_expect_success 'clone of empty repo propagates name of default branch' ' + test_when_finished "rm -rf file_empty_parent file_empty_child" && + + GIT_TEST_DEFAULT_INITIAL_BRANCH_NAME= \ + git -c init.defaultBranch=mydefaultbranch init file_empty_parent && + + GIT_TEST_DEFAULT_INITIAL_BRANCH_NAME= \ + git -c init.defaultBranch=main -c protocol.version=2 \ + clone "file://$(pwd)/file_empty_parent" file_empty_child && + grep "refs/heads/mydefaultbranch" file_empty_child/.git/HEAD +' + +test_expect_success '...but not if explicitly forbidden by config' ' + test_when_finished "rm -rf file_empty_parent file_empty_child" && + + GIT_TEST_DEFAULT_INITIAL_BRANCH_NAME= \ + git -c init.defaultBranch=mydefaultbranch init file_empty_parent && + test_config -C file_empty_parent lsrefs.unborn ignore && + + GIT_TEST_DEFAULT_INITIAL_BRANCH_NAME= \ + git -c init.defaultBranch=main -c protocol.version=2 \ + clone "file://$(pwd)/file_empty_parent" file_empty_child && + ! grep "refs/heads/mydefaultbranch" file_empty_child/.git/HEAD +' + test_expect_success 'fetch with file:// using protocol v2' ' test_when_finished "rm -f log" && diff --git a/transport.h b/transport.h index 1f5b60e4d31..24e15799e71 100644 --- a/transport.h +++ b/transport.h @@ -243,6 +243,14 @@ struct transport_ls_refs_options { * provided ref_prefixes. */ struct strvec ref_prefixes; + + /* + * If unborn_head_target is not NULL, and the remote reports HEAD as + * pointing to an unborn branch, transport_get_remote_refs() stores the + * unborn branch in unborn_head_target. It should be freed by the + * caller. + */ + char *unborn_head_target; }; #define TRANSPORT_LS_REFS_OPTIONS_INIT { STRVEC_INIT }