[WIP 15/15] fetch-pack: perform a fetch using v2
- From
- Brandon Williams <bmwill@google.com>
- Date
- Dec 4, 2017, 23:58 UTC
- Message-ID
- <20171204235823.63299-16-bmwill@google.com>
- In-Reply-To
- <20171204235823.63299-1-bmwill@google.com>
When communicating with a v2 server, perform a fetch by requesting the 'fetch' command.
Signed-off-by: Brandon Williams <bmwill@google.com> --- builtin/fetch-pack.c | 2 +- fetch-pack.c | 237 ++++++++++++++++++++++++++++++++++++++++++++++++- fetch-pack.h | 4 +- t/t5701-protocol-v2.sh | 26 ++++++ transport.c | 8 +- 5 files changed, 270 insertions(+), 7 deletions(-)
diff --git a/builtin/fetch-pack.c b/builtin/fetch-pack.c index 061c278b4..e02c7761b 100644 --- a/builtin/fetch-pack.c +++ b/builtin/fetch-pack.c @@ -211,7 +211,7 @@ int cmd_fetch_pack(int argc, const char **argv, const char *prefix) } ref = fetch_pack(&args, fd, conn, ref, dest, sought, nr_sought, - &shallow, pack_lockfile_ptr); + &shallow, pack_lockfile_ptr, protocol_v0); if (pack_lockfile) { printf("lock %s\n", pack_lockfile); fflush(stdout); diff --git a/fetch-pack.c b/fetch-pack.c index 105506e9a..a8ef8f3e5 100644 --- a/fetch-pack.c +++ b/fetch-pack.c @@ -1007,6 +1007,232 @@ static struct ref *do_fetch_pack(struct fetch_pack_args *args, return ref; } +static void add_wants(const struct ref *wants, struct strbuf *req_buf) +{ + for ( ; wants ; wants = wants->next) { + const struct object_id *remote = &wants->old_oid; + const char *remote_hex; + struct object *o; + + /* + * If that object is complete (i.e. it is an ancestor of a + * local ref), we tell them we have it but do not have to + * tell them about its ancestors, which they already know + * about. + * + * We use lookup_object here because we are only + * interested in the case we *know* the object is + * reachable and we have already scanned it. + */ + if (((o = lookup_object(remote->hash)) != NULL) && + (o->flags & COMPLETE)) { + continue; + } + + remote_hex = oid_to_hex(remote); + packet_buf_write(req_buf, "want %s\n", remote_hex); + } +} + +/* */ +static int add_haves(struct strbuf *req_buf) +{ + int count = 0; + const struct object_id *oid; + while ((oid = get_rev())) { + packet_buf_write(req_buf, "have %s\n", oid_to_hex(oid)); + if (++count >= INITIAL_FLUSH) + break; + }; + + return count; +} + +static int send_fetch_request(int fd_out, const struct fetch_pack_args *args, + const struct ref *wants) +{ + int ret = 0; + struct strbuf req_buf = STRBUF_INIT; + + use_sideband = 2; + packet_buf_write(&req_buf, "command=fetch"); + packet_buf_write(&req_buf, "agent=%s", git_user_agent_sanitized()); + packet_buf_delim(&req_buf); + if (args->use_thin_pack) + packet_buf_write(&req_buf, "thin-pack"); + if (args->no_progress) + packet_buf_write(&req_buf, "no-progress"); + if (args->include_tag) + packet_buf_write(&req_buf, "include-tag"); + if (prefer_ofs_delta) + packet_buf_write(&req_buf, "ofs-delta"); + + /* add wants */ + add_wants(wants, &req_buf); + + /* Add initial haves */ + ret = add_haves(&req_buf); + + /* Send request */ + packet_buf_flush(&req_buf); + write_or_die(fd_out, req_buf.buf, req_buf.len); + + strbuf_release(&req_buf); + return ret; +} + +static enum ack_type process_ack(const char *line, struct object_id *oid) +{ + const char *arg; + + if (!strcmp(line, "NAK")) + return NAK; + if (skip_prefix(line, "ACK ", &arg)) { + if (!parse_oid_hex(arg, oid, &arg)) { + if (strstr(arg, "continue")) + return ACK_continue; + if (strstr(arg, "common")) + return ACK_common; + if (strstr(arg, "ready")) + return ACK_ready; + return ACK; + } + } + if (skip_prefix(line, "ERR ", &arg)) + die(_("remote error: %s"), arg); + die(_("git fetch-pack: expected ACK/NAK, got '%s'"), line); +} + +static int process_acks(struct packet_reader *reader) +{ + int got_ready = 0; + int got_common = 0; + while (packet_reader_read(reader) == PACKET_READ_NORMAL) { + struct object_id oid; + struct commit *commit; + enum ack_type ack = process_ack(reader->line, &oid); + + switch (ack) { + case ACK_ready: + clear_prio_queue(&rev_list); + got_ready = 1; + /* fallthrough */ + case ACK_common: + commit = lookup_commit(&oid); + mark_common(commit, 0, 1); + got_common = 1; + break; + case NAK: + break; + case ACK: + case ACK_continue: + die("ACK/ACK_continue not supported"); + } + } + + if (reader->status != PACKET_READ_FLUSH && + reader->status != PACKET_READ_DELIM) + die("Error during processing acks: %d",reader->status); + + /* return 0 if no common, 1 if there are common, or 2 if ready */ + return got_ready + got_common; +} + +static int send_haves(int fd_out, int *in_vain) +{ + int ret = 0; + struct strbuf req_buf = STRBUF_INIT; + int haves_added = add_haves(&req_buf); + + *in_vain += haves_added; + if (!haves_added || *in_vain >= MAX_IN_VAIN) { + /* Send Done */ + packet_buf_write(&req_buf, "done\n"); + ret = 1; + } + + /* Send request */ + packet_buf_flush(&req_buf); + write_or_die(fd_out, req_buf.buf, req_buf.len); + + strbuf_release(&req_buf); + return ret; +} + +#define FETCH_PACK_CHECK_LOCAL 0 +#define FETCH_PACK_REQUEST 1 +#define FETCH_PACK_ACKS 2 +#define FETCH_PACK_HAVES 3 +#define FETCH_PACK_GET_PACK 4 +#define FETCH_PACK_DONE 5 + +static struct ref *do_fetch_pack_v2(struct fetch_pack_args *args, + int fd[2], + const struct ref *orig_ref, + struct ref **sought, int nr_sought, + char **pack_lockfile) +{ + struct ref *ref = copy_ref_list(orig_ref); + int state = FETCH_PACK_CHECK_LOCAL; + struct packet_reader reader; + int in_vain = 0; + packet_reader_init(&reader, fd[0], NULL, 0); + + while (state != FETCH_PACK_DONE) { + switch (state) { + case FETCH_PACK_CHECK_LOCAL: + sort_ref_list(&ref, ref_compare_name); + QSORT(sought, nr_sought, cmp_ref_by_name); + + /* Filter 'ref' by 'sought' and those that aren't local */ + if (everything_local(args, &ref, sought, nr_sought)) + state = FETCH_PACK_DONE; + else + state = FETCH_PACK_REQUEST; + break; + case FETCH_PACK_REQUEST: + if (send_fetch_request(fd[1], args, ref)) + state = FETCH_PACK_ACKS; + else + state = FETCH_PACK_GET_PACK; + break; + case FETCH_PACK_ACKS: + /* Process ACKs/NAKs */ + switch (process_acks(&reader)) { + case 2: + state = FETCH_PACK_GET_PACK; + break; + case 1: + in_vain = 0; + /* fallthrough */ + default: + state = FETCH_PACK_HAVES; + break; + } + break; + case FETCH_PACK_HAVES: + if (send_haves(fd[1], &in_vain)) + state = FETCH_PACK_GET_PACK; + else + state = FETCH_PACK_ACKS; + break; + case FETCH_PACK_GET_PACK: + /* get the pack */ + if (get_pack(args, fd, pack_lockfile)) + die(_("git fetch-pack: fetch failed.")); + + state = FETCH_PACK_DONE; + break; + case FETCH_PACK_DONE: + break; + default: + die("invalid state"); + } + } + + return ref; +} + static void fetch_pack_config(void) { git_config_get_int("fetch.unpacklimit", &fetch_unpack_limit); @@ -1152,7 +1378,8 @@ struct ref *fetch_pack(struct fetch_pack_args *args, const char *dest, struct ref **sought, int nr_sought, struct oid_array *shallow, - char **pack_lockfile) + char **pack_lockfile, + enum protocol_version version) { struct ref *ref_cpy; struct shallow_info si; @@ -1166,8 +1393,12 @@ struct ref *fetch_pack(struct fetch_pack_args *args, die(_("no matching remote head")); } prepare_shallow_info(&si, shallow); - ref_cpy = do_fetch_pack(args, fd, ref, sought, nr_sought, - &si, pack_lockfile); + if (version == protocol_v2) + ref_cpy = do_fetch_pack_v2(args, fd, ref, sought, nr_sought, + pack_lockfile); + else + ref_cpy = do_fetch_pack(args, fd, ref, sought, nr_sought, + &si, pack_lockfile); reprepare_packed_git(); update_shallow(args, sought, nr_sought, &si); clear_shallow_info(&si); diff --git a/fetch-pack.h b/fetch-pack.h index b6aeb43a8..7afca7305 100644 --- a/fetch-pack.h +++ b/fetch-pack.h @@ -3,6 +3,7 @@ #include "string-list.h" #include "run-command.h" +#include "protocol.h" struct oid_array; @@ -43,7 +44,8 @@ struct ref *fetch_pack(struct fetch_pack_args *args, struct ref **sought, int nr_sought, struct oid_array *shallow, - char **pack_lockfile); + char **pack_lockfile, + enum protocol_version version); /* * Print an appropriate error message for each sought ref that wasn't diff --git a/t/t5701-protocol-v2.sh b/t/t5701-protocol-v2.sh index 4bf4d61ac..c788ea597 100755 --- a/t/t5701-protocol-v2.sh +++ b/t/t5701-protocol-v2.sh @@ -25,4 +25,30 @@ test_expect_success 'list refs with file:// using protocol v2' ' test_cmp actual expect ' +test_expect_success 'clone with file:// using protocol v2' ' + GIT_TRACE_PACKET=1 git -c protocol.version=2 \ + clone "file://$(pwd)/file_parent" file_child 2>log && + + git -C file_child log -1 --format=%s >actual && + git -C file_parent log -1 --format=%s >expect && + test_cmp expect actual && + + # Server responded using protocol v1 + grep "clone< version 2" log +' + +test_expect_success 'fetch with file:// using protocol v2' ' + test_commit -C file_parent two && + + GIT_TRACE_PACKET=1 git -C file_child -c protocol.version=2 \ + fetch origin 2>log && + + git -C file_child log -1 --format=%s origin/master >actual && + git -C file_parent log -1 --format=%s >expect && + test_cmp expect actual && + + # Server responded using protocol v1 + grep "fetch< version 2" log +' + test_done diff --git a/transport.c b/transport.c index ddd0d6174..50354abed 100644 --- a/transport.c +++ b/transport.c @@ -252,14 +252,18 @@ static int fetch_refs_via_pack(struct transport *transport, switch (data->version) { case protocol_v2: - die("support for protocol v2 not implemented yet"); + refs = fetch_pack(&args, data->fd, data->conn, + refs_tmp ? refs_tmp : transport->remote_refs, + dest, to_fetch, nr_heads, &data->shallow, + &transport->pack_lockfile, data->version); + packet_flush(data->fd[1]); break; case protocol_v1: case protocol_v0: refs = fetch_pack(&args, data->fd, data->conn, refs_tmp ? refs_tmp : transport->remote_refs, dest, to_fetch, nr_heads, &data->shallow, - &transport->pack_lockfile); + &transport->pack_lockfile, data->version); break; case protocol_unknown_version: BUG("unknown protocol version");
-- 2.15.1.424.g9478a66081-goog