diff options
Diffstat (limited to 'fetch-pack.c')
| -rw-r--r-- | fetch-pack.c | 2245 |
1 files changed, 2245 insertions, 0 deletions
diff --git a/fetch-pack.c b/fetch-pack.c new file mode 100644 index 0000000..26999e3 --- /dev/null +++ b/fetch-pack.c @@ -0,0 +1,2245 @@ +#include "git-compat-util.h" +#include "repository.h" +#include "config.h" +#include "date.h" +#include "environment.h" +#include "gettext.h" +#include "hex.h" +#include "lockfile.h" +#include "refs.h" +#include "pkt-line.h" +#include "commit.h" +#include "tag.h" +#include "exec-cmd.h" +#include "pack.h" +#include "sideband.h" +#include "fetch-pack.h" +#include "remote.h" +#include "run-command.h" +#include "connect.h" +#include "trace2.h" +#include "transport.h" +#include "version.h" +#include "oid-array.h" +#include "oidset.h" +#include "packfile.h" +#include "object-store-ll.h" +#include "path.h" +#include "connected.h" +#include "fetch-negotiator.h" +#include "fsck.h" +#include "shallow.h" +#include "commit-reach.h" +#include "commit-graph.h" +#include "sigchain.h" +#include "mergesort.h" + +static int transfer_unpack_limit = -1; +static int fetch_unpack_limit = -1; +static int unpack_limit = 100; +static int prefer_ofs_delta = 1; +static int no_done; +static int deepen_since_ok; +static int deepen_not_ok; +static int fetch_fsck_objects = -1; +static int transfer_fsck_objects = -1; +static int agent_supported; +static int server_supports_filtering; +static int advertise_sid; +static struct shallow_lock shallow_lock; +static const char *alternate_shallow_file; +static struct fsck_options fsck_options = FSCK_OPTIONS_MISSING_GITMODULES; +static struct strbuf fsck_msg_types = STRBUF_INIT; +static struct string_list uri_protocols = STRING_LIST_INIT_DUP; + +/* Remember to update object flag allocation in object.h */ +#define COMPLETE (1U << 0) +#define ALTERNATE (1U << 1) +#define COMMON (1U << 6) +#define REACH_SCRATCH (1U << 7) + +/* + * After sending this many "have"s if we do not get any new ACK , we + * give up traversing our history. + */ +#define MAX_IN_VAIN 256 + +static int multi_ack, use_sideband; +/* Allow specifying sha1 if it is a ref tip. */ +#define ALLOW_TIP_SHA1 01 +/* Allow request of a sha1 if it is reachable from a ref (possibly hidden ref). */ +#define ALLOW_REACHABLE_SHA1 02 +static unsigned int allow_unadvertised_object_request; + +__attribute__((format (printf, 2, 3))) +static inline void print_verbose(const struct fetch_pack_args *args, + const char *fmt, ...) +{ + va_list params; + + if (!args->verbose) + return; + + va_start(params, fmt); + vfprintf(stderr, fmt, params); + va_end(params); + fputc('\n', stderr); +} + +struct alternate_object_cache { + struct object **items; + size_t nr, alloc; +}; + +static void cache_one_alternate(const struct object_id *oid, + void *vcache) +{ + struct alternate_object_cache *cache = vcache; + struct object *obj = parse_object(the_repository, oid); + + if (!obj || (obj->flags & ALTERNATE)) + return; + + obj->flags |= ALTERNATE; + ALLOC_GROW(cache->items, cache->nr + 1, cache->alloc); + cache->items[cache->nr++] = obj; +} + +static void for_each_cached_alternate(struct fetch_negotiator *negotiator, + void (*cb)(struct fetch_negotiator *, + struct object *)) +{ + static int initialized; + static struct alternate_object_cache cache; + size_t i; + + if (!initialized) { + for_each_alternate_ref(cache_one_alternate, &cache); + initialized = 1; + } + + for (i = 0; i < cache.nr; i++) + cb(negotiator, cache.items[i]); +} + +static struct commit *deref_without_lazy_fetch_extended(const struct object_id *oid, + int mark_tags_complete, + enum object_type *type, + unsigned int oi_flags) +{ + struct object_info info = { .typep = type }; + struct commit *commit; + + commit = lookup_commit_in_graph(the_repository, oid); + if (commit) + return commit; + + while (1) { + if (oid_object_info_extended(the_repository, oid, &info, + oi_flags)) + return NULL; + if (*type == OBJ_TAG) { + struct tag *tag = (struct tag *) + parse_object(the_repository, oid); + + if (!tag->tagged) + return NULL; + if (mark_tags_complete) + tag->object.flags |= COMPLETE; + oid = &tag->tagged->oid; + } else { + break; + } + } + + if (*type == OBJ_COMMIT) { + struct commit *commit = lookup_commit(the_repository, oid); + if (!commit || repo_parse_commit(the_repository, commit)) + return NULL; + return commit; + } + + return NULL; +} + + +static struct commit *deref_without_lazy_fetch(const struct object_id *oid, + int mark_tags_complete) +{ + enum object_type type; + unsigned flags = OBJECT_INFO_SKIP_FETCH_OBJECT | OBJECT_INFO_QUICK; + return deref_without_lazy_fetch_extended(oid, mark_tags_complete, + &type, flags); +} + +static int rev_list_insert_ref(struct fetch_negotiator *negotiator, + const struct object_id *oid) +{ + struct commit *c = deref_without_lazy_fetch(oid, 0); + + if (c) + negotiator->add_tip(negotiator, c); + return 0; +} + +static int rev_list_insert_ref_oid(const char *refname UNUSED, + const struct object_id *oid, + int flag UNUSED, + void *cb_data) +{ + return rev_list_insert_ref(cb_data, oid); +} + +enum ack_type { + NAK = 0, + ACK, + ACK_continue, + ACK_common, + ACK_ready +}; + +static void consume_shallow_list(struct fetch_pack_args *args, + struct packet_reader *reader) +{ + if (args->stateless_rpc && args->deepen) { + /* If we sent a depth we will get back "duplicate" + * shallow and unshallow commands every time there + * is a block of have lines exchanged. + */ + while (packet_reader_read(reader) == PACKET_READ_NORMAL) { + if (starts_with(reader->line, "shallow ")) + continue; + if (starts_with(reader->line, "unshallow ")) + continue; + die(_("git fetch-pack: expected shallow list")); + } + if (reader->status != PACKET_READ_FLUSH) + die(_("git fetch-pack: expected a flush packet after shallow list")); + } +} + +static enum ack_type get_ack(struct packet_reader *reader, + struct object_id *result_oid) +{ + int len; + const char *arg; + + if (packet_reader_read(reader) != PACKET_READ_NORMAL) + die(_("git fetch-pack: expected ACK/NAK, got a flush packet")); + len = reader->pktlen; + + if (!strcmp(reader->line, "NAK")) + return NAK; + if (skip_prefix(reader->line, "ACK ", &arg)) { + const char *p; + if (!parse_oid_hex(arg, result_oid, &p)) { + len -= p - reader->line; + if (len < 1) + return ACK; + if (strstr(p, "continue")) + return ACK_continue; + if (strstr(p, "common")) + return ACK_common; + if (strstr(p, "ready")) + return ACK_ready; + return ACK; + } + } + die(_("git fetch-pack: expected ACK/NAK, got '%s'"), reader->line); +} + +static void send_request(struct fetch_pack_args *args, + int fd, struct strbuf *buf) +{ + if (args->stateless_rpc) { + send_sideband(fd, -1, buf->buf, buf->len, LARGE_PACKET_MAX); + packet_flush(fd); + } else { + if (write_in_full(fd, buf->buf, buf->len) < 0) + die_errno(_("unable to write to remote")); + } +} + +static void insert_one_alternate_object(struct fetch_negotiator *negotiator, + struct object *obj) +{ + rev_list_insert_ref(negotiator, &obj->oid); +} + +#define INITIAL_FLUSH 16 +#define PIPESAFE_FLUSH 32 +#define LARGE_FLUSH 16384 + +static int next_flush(int stateless_rpc, int count) +{ + if (stateless_rpc) { + if (count < LARGE_FLUSH) + count <<= 1; + else + count = count * 11 / 10; + } else { + if (count < PIPESAFE_FLUSH) + count <<= 1; + else + count += PIPESAFE_FLUSH; + } + return count; +} + +static void mark_tips(struct fetch_negotiator *negotiator, + const struct oid_array *negotiation_tips) +{ + int i; + + if (!negotiation_tips) { + for_each_rawref(rev_list_insert_ref_oid, negotiator); + return; + } + + for (i = 0; i < negotiation_tips->nr; i++) + rev_list_insert_ref(negotiator, &negotiation_tips->oid[i]); + return; +} + +static void send_filter(struct fetch_pack_args *args, + struct strbuf *req_buf, + int server_supports_filter) +{ + if (args->filter_options.choice) { + const char *spec = + expand_list_objects_filter_spec(&args->filter_options); + if (server_supports_filter) { + print_verbose(args, _("Server supports filter")); + packet_buf_write(req_buf, "filter %s", spec); + trace2_data_string("fetch", the_repository, + "filter/effective", spec); + } else { + warning("filtering not recognized by server, ignoring"); + trace2_data_string("fetch", the_repository, + "filter/unsupported", spec); + } + } else { + trace2_data_string("fetch", the_repository, + "filter/none", ""); + } +} + +static int find_common(struct fetch_negotiator *negotiator, + struct fetch_pack_args *args, + int fd[2], struct object_id *result_oid, + struct ref *refs) +{ + int fetching; + int count = 0, flushes = 0, flush_at = INITIAL_FLUSH, retval; + int negotiation_round = 0, haves = 0; + const struct object_id *oid; + unsigned in_vain = 0; + int got_continue = 0; + int got_ready = 0; + struct strbuf req_buf = STRBUF_INIT; + size_t state_len = 0; + struct packet_reader reader; + + if (args->stateless_rpc && multi_ack == 1) + die(_("the option '%s' requires '%s'"), "--stateless-rpc", "multi_ack_detailed"); + + packet_reader_init(&reader, fd[0], NULL, 0, + PACKET_READ_CHOMP_NEWLINE | + PACKET_READ_DIE_ON_ERR_PACKET); + + mark_tips(negotiator, args->negotiation_tips); + for_each_cached_alternate(negotiator, insert_one_alternate_object); + + fetching = 0; + for ( ; refs ; refs = refs->next) { + struct object_id *remote = &refs->old_oid; + const char *remote_hex; + struct object *o; + + if (!args->refetch) { + /* + * 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(the_repository, remote)) != NULL) && + (o->flags & COMPLETE)) { + continue; + } + } + + remote_hex = oid_to_hex(remote); + if (!fetching) { + struct strbuf c = STRBUF_INIT; + if (multi_ack == 2) strbuf_addstr(&c, " multi_ack_detailed"); + if (multi_ack == 1) strbuf_addstr(&c, " multi_ack"); + if (no_done) strbuf_addstr(&c, " no-done"); + if (use_sideband == 2) strbuf_addstr(&c, " side-band-64k"); + if (use_sideband == 1) strbuf_addstr(&c, " side-band"); + if (args->deepen_relative) strbuf_addstr(&c, " deepen-relative"); + if (args->use_thin_pack) strbuf_addstr(&c, " thin-pack"); + if (args->no_progress) strbuf_addstr(&c, " no-progress"); + if (args->include_tag) strbuf_addstr(&c, " include-tag"); + if (prefer_ofs_delta) strbuf_addstr(&c, " ofs-delta"); + if (deepen_since_ok) strbuf_addstr(&c, " deepen-since"); + if (deepen_not_ok) strbuf_addstr(&c, " deepen-not"); + if (agent_supported) strbuf_addf(&c, " agent=%s", + git_user_agent_sanitized()); + if (advertise_sid) + strbuf_addf(&c, " session-id=%s", trace2_session_id()); + if (args->filter_options.choice) + strbuf_addstr(&c, " filter"); + packet_buf_write(&req_buf, "want %s%s\n", remote_hex, c.buf); + strbuf_release(&c); + } else + packet_buf_write(&req_buf, "want %s\n", remote_hex); + fetching++; + } + + if (!fetching) { + strbuf_release(&req_buf); + packet_flush(fd[1]); + return 1; + } + + if (is_repository_shallow(the_repository)) + write_shallow_commits(&req_buf, 1, NULL); + if (args->depth > 0) + packet_buf_write(&req_buf, "deepen %d", args->depth); + if (args->deepen_since) { + timestamp_t max_age = approxidate(args->deepen_since); + packet_buf_write(&req_buf, "deepen-since %"PRItime, max_age); + } + if (args->deepen_not) { + int i; + for (i = 0; i < args->deepen_not->nr; i++) { + struct string_list_item *s = args->deepen_not->items + i; + packet_buf_write(&req_buf, "deepen-not %s", s->string); + } + } + send_filter(args, &req_buf, server_supports_filtering); + packet_buf_flush(&req_buf); + state_len = req_buf.len; + + if (args->deepen) { + const char *arg; + struct object_id oid; + + send_request(args, fd[1], &req_buf); + while (packet_reader_read(&reader) == PACKET_READ_NORMAL) { + if (skip_prefix(reader.line, "shallow ", &arg)) { + if (get_oid_hex(arg, &oid)) + die(_("invalid shallow line: %s"), reader.line); + register_shallow(the_repository, &oid); + continue; + } + if (skip_prefix(reader.line, "unshallow ", &arg)) { + if (get_oid_hex(arg, &oid)) + die(_("invalid unshallow line: %s"), reader.line); + if (!lookup_object(the_repository, &oid)) + die(_("object not found: %s"), reader.line); + /* make sure that it is parsed as shallow */ + if (!parse_object(the_repository, &oid)) + die(_("error in object: %s"), reader.line); + if (unregister_shallow(&oid)) + die(_("no shallow found: %s"), reader.line); + continue; + } + die(_("expected shallow/unshallow, got %s"), reader.line); + } + } else if (!args->stateless_rpc) + send_request(args, fd[1], &req_buf); + + if (!args->stateless_rpc) { + /* If we aren't using the stateless-rpc interface + * we don't need to retain the headers. + */ + strbuf_setlen(&req_buf, 0); + state_len = 0; + } + + trace2_region_enter("fetch-pack", "negotiation_v0_v1", the_repository); + flushes = 0; + retval = -1; + while ((oid = negotiator->next(negotiator))) { + packet_buf_write(&req_buf, "have %s\n", oid_to_hex(oid)); + print_verbose(args, "have %s", oid_to_hex(oid)); + in_vain++; + haves++; + if (flush_at <= ++count) { + int ack; + + negotiation_round++; + trace2_region_enter_printf("negotiation_v0_v1", "round", + the_repository, "%d", + negotiation_round); + trace2_data_intmax("negotiation_v0_v1", the_repository, + "haves_added", haves); + trace2_data_intmax("negotiation_v0_v1", the_repository, + "in_vain", in_vain); + haves = 0; + packet_buf_flush(&req_buf); + send_request(args, fd[1], &req_buf); + strbuf_setlen(&req_buf, state_len); + flushes++; + flush_at = next_flush(args->stateless_rpc, count); + + /* + * We keep one window "ahead" of the other side, and + * will wait for an ACK only on the next one + */ + if (!args->stateless_rpc && count == INITIAL_FLUSH) + continue; + + consume_shallow_list(args, &reader); + do { + ack = get_ack(&reader, result_oid); + if (ack) + print_verbose(args, _("got %s %d %s"), "ack", + ack, oid_to_hex(result_oid)); + switch (ack) { + case ACK: + trace2_region_leave_printf("negotiation_v0_v1", "round", + the_repository, "%d", + negotiation_round); + flushes = 0; + multi_ack = 0; + retval = 0; + goto done; + case ACK_common: + case ACK_ready: + case ACK_continue: { + struct commit *commit = + lookup_commit(the_repository, + result_oid); + int was_common; + + if (!commit) + die(_("invalid commit %s"), oid_to_hex(result_oid)); + was_common = negotiator->ack(negotiator, commit); + if (args->stateless_rpc + && ack == ACK_common + && !was_common) { + /* We need to replay the have for this object + * on the next RPC request so the peer knows + * it is in common with us. + */ + const char *hex = oid_to_hex(result_oid); + packet_buf_write(&req_buf, "have %s\n", hex); + state_len = req_buf.len; + haves++; + /* + * Reset in_vain because an ack + * for this commit has not been + * seen. + */ + in_vain = 0; + } else if (!args->stateless_rpc + || ack != ACK_common) + in_vain = 0; + retval = 0; + got_continue = 1; + if (ack == ACK_ready) + got_ready = 1; + break; + } + } + } while (ack); + flushes--; + trace2_region_leave_printf("negotiation_v0_v1", "round", + the_repository, "%d", + negotiation_round); + if (got_continue && MAX_IN_VAIN < in_vain) { + print_verbose(args, _("giving up")); + break; /* give up */ + } + if (got_ready) + break; + } + } +done: + trace2_region_leave("fetch-pack", "negotiation_v0_v1", the_repository); + trace2_data_intmax("negotiation_v0_v1", the_repository, "total_rounds", + negotiation_round); + if (!got_ready || !no_done) { + packet_buf_write(&req_buf, "done\n"); + send_request(args, fd[1], &req_buf); + } + print_verbose(args, _("done")); + if (retval != 0) { + multi_ack = 0; + flushes++; + } + strbuf_release(&req_buf); + + if (!got_ready || !no_done) + consume_shallow_list(args, &reader); + while (flushes || multi_ack) { + int ack = get_ack(&reader, result_oid); + if (ack) { + print_verbose(args, _("got %s (%d) %s"), "ack", + ack, oid_to_hex(result_oid)); + if (ack == ACK) + return 0; + multi_ack = 1; + continue; + } + flushes--; + } + /* it is no error to fetch into a completely empty repo */ + return count ? retval : 0; +} + +static struct commit_list *complete; + +static int mark_complete(const struct object_id *oid) +{ + struct commit *commit = deref_without_lazy_fetch(oid, 1); + + if (commit && !(commit->object.flags & COMPLETE)) { + commit->object.flags |= COMPLETE; + commit_list_insert(commit, &complete); + } + return 0; +} + +static int mark_complete_oid(const char *refname UNUSED, + const struct object_id *oid, + int flag UNUSED, + void *cb_data UNUSED) +{ + return mark_complete(oid); +} + +static void mark_recent_complete_commits(struct fetch_pack_args *args, + timestamp_t cutoff) +{ + while (complete && cutoff <= complete->item->date) { + print_verbose(args, _("Marking %s as complete"), + oid_to_hex(&complete->item->object.oid)); + pop_most_recent_commit(&complete, COMPLETE); + } +} + +static void add_refs_to_oidset(struct oidset *oids, struct ref *refs) +{ + for (; refs; refs = refs->next) + oidset_insert(oids, &refs->old_oid); +} + +static int is_unmatched_ref(const struct ref *ref) +{ + struct object_id oid; + const char *p; + return ref->match_status == REF_NOT_MATCHED && + !parse_oid_hex(ref->name, &oid, &p) && + *p == '\0' && + oideq(&oid, &ref->old_oid); +} + +static void filter_refs(struct fetch_pack_args *args, + struct ref **refs, + struct ref **sought, int nr_sought) +{ + struct ref *newlist = NULL; + struct ref **newtail = &newlist; + struct ref *unmatched = NULL; + struct ref *ref, *next; + struct oidset tip_oids = OIDSET_INIT; + int i; + int strict = !(allow_unadvertised_object_request & + (ALLOW_TIP_SHA1 | ALLOW_REACHABLE_SHA1)); + + i = 0; + for (ref = *refs; ref; ref = next) { + int keep = 0; + next = ref->next; + + if (starts_with(ref->name, "refs/") && + check_refname_format(ref->name, 0)) { + /* + * trash or a peeled value; do not even add it to + * unmatched list + */ + free_one_ref(ref); + continue; + } else { + while (i < nr_sought) { + int cmp = strcmp(ref->name, sought[i]->name); + if (cmp < 0) + break; /* definitely do not have it */ + else if (cmp == 0) { + keep = 1; /* definitely have it */ + sought[i]->match_status = REF_MATCHED; + } + i++; + } + + if (!keep && args->fetch_all && + (!args->deepen || !starts_with(ref->name, "refs/tags/"))) + keep = 1; + } + + if (keep) { + *newtail = ref; + ref->next = NULL; + newtail = &ref->next; + } else { + ref->next = unmatched; + unmatched = ref; + } + } + + if (strict) { + for (i = 0; i < nr_sought; i++) { + ref = sought[i]; + if (!is_unmatched_ref(ref)) + continue; + + add_refs_to_oidset(&tip_oids, unmatched); + add_refs_to_oidset(&tip_oids, newlist); + break; + } + } + + /* Append unmatched requests to the list */ + for (i = 0; i < nr_sought; i++) { + ref = sought[i]; + if (!is_unmatched_ref(ref)) + continue; + + if (!strict || oidset_contains(&tip_oids, &ref->old_oid)) { + ref->match_status = REF_MATCHED; + *newtail = copy_ref(ref); + newtail = &(*newtail)->next; + } else { + ref->match_status = REF_UNADVERTISED_NOT_ALLOWED; + } + } + + oidset_clear(&tip_oids); + free_refs(unmatched); + + *refs = newlist; +} + +static void mark_alternate_complete(struct fetch_negotiator *negotiator UNUSED, + struct object *obj) +{ + mark_complete(&obj->oid); +} + +struct loose_object_iter { + struct oidset *loose_object_set; + struct ref *refs; +}; + +/* + * Mark recent commits available locally and reachable from a local ref as + * COMPLETE. + * + * The cutoff time for recency is determined by this heuristic: it is the + * earliest commit time of the objects in refs that are commits and that we know + * the commit time of. + */ +static void mark_complete_and_common_ref(struct fetch_negotiator *negotiator, + struct fetch_pack_args *args, + struct ref **refs) +{ + struct ref *ref; + int old_save_commit_buffer = save_commit_buffer; + timestamp_t cutoff = 0; + + if (args->refetch) + return; + + save_commit_buffer = 0; + + trace2_region_enter("fetch-pack", "parse_remote_refs_and_find_cutoff", NULL); + for (ref = *refs; ref; ref = ref->next) { + struct commit *commit; + + commit = lookup_commit_in_graph(the_repository, &ref->old_oid); + if (!commit) { + struct object *o; + + if (!repo_has_object_file_with_flags(the_repository, &ref->old_oid, + OBJECT_INFO_QUICK | + OBJECT_INFO_SKIP_FETCH_OBJECT)) + continue; + o = parse_object(the_repository, &ref->old_oid); + if (!o || o->type != OBJ_COMMIT) + continue; + + commit = (struct commit *)o; + } + + /* + * We already have it -- which may mean that we were + * in sync with the other side at some time after + * that (it is OK if we guess wrong here). + */ + if (!cutoff || cutoff < commit->date) + cutoff = commit->date; + } + trace2_region_leave("fetch-pack", "parse_remote_refs_and_find_cutoff", NULL); + + /* + * This block marks all local refs as COMPLETE, and then recursively marks all + * parents of those refs as COMPLETE. + */ + trace2_region_enter("fetch-pack", "mark_complete_local_refs", NULL); + if (!args->deepen) { + for_each_rawref(mark_complete_oid, NULL); + for_each_cached_alternate(NULL, mark_alternate_complete); + commit_list_sort_by_date(&complete); + if (cutoff) + mark_recent_complete_commits(args, cutoff); + } + trace2_region_leave("fetch-pack", "mark_complete_local_refs", NULL); + + /* + * Mark all complete remote refs as common refs. + * Don't mark them common yet; the server has to be told so first. + */ + trace2_region_enter("fetch-pack", "mark_common_remote_refs", NULL); + for (ref = *refs; ref; ref = ref->next) { + struct commit *c = deref_without_lazy_fetch(&ref->old_oid, 0); + + if (!c || !(c->object.flags & COMPLETE)) + continue; + + negotiator->known_common(negotiator, c); + } + trace2_region_leave("fetch-pack", "mark_common_remote_refs", NULL); + + save_commit_buffer = old_save_commit_buffer; +} + +/* + * Returns 1 if every object pointed to by the given remote refs is available + * locally and reachable from a local ref, and 0 otherwise. + */ +static int everything_local(struct fetch_pack_args *args, + struct ref **refs) +{ + struct ref *ref; + int retval; + + for (retval = 1, ref = *refs; ref ; ref = ref->next) { + const struct object_id *remote = &ref->old_oid; + struct object *o; + + o = lookup_object(the_repository, remote); + if (!o || !(o->flags & COMPLETE)) { + retval = 0; + print_verbose(args, "want %s (%s)", oid_to_hex(remote), + ref->name); + continue; + } + print_verbose(args, _("already have %s (%s)"), oid_to_hex(remote), + ref->name); + } + + return retval; +} + +static int sideband_demux(int in UNUSED, int out, void *data) +{ + int *xd = data; + int ret; + + ret = recv_sideband("fetch-pack", xd[0], out); + close(out); + return ret; +} + +static void create_promisor_file(const char *keep_name, + struct ref **sought, int nr_sought) +{ + struct strbuf promisor_name = STRBUF_INIT; + int suffix_stripped; + + strbuf_addstr(&promisor_name, keep_name); + suffix_stripped = strbuf_strip_suffix(&promisor_name, ".keep"); + if (!suffix_stripped) + BUG("name of pack lockfile should end with .keep (was '%s')", + keep_name); + strbuf_addstr(&promisor_name, ".promisor"); + + write_promisor_file(promisor_name.buf, sought, nr_sought); + + strbuf_release(&promisor_name); +} + +static void parse_gitmodules_oids(int fd, struct oidset *gitmodules_oids) +{ + int len = the_hash_algo->hexsz + 1; /* hash + NL */ + + do { + char hex_hash[GIT_MAX_HEXSZ + 1]; + int read_len = read_in_full(fd, hex_hash, len); + struct object_id oid; + const char *end; + + if (!read_len) + return; + if (read_len != len) + die("invalid length read %d", read_len); + if (parse_oid_hex(hex_hash, &oid, &end) || *end != '\n') + die("invalid hash"); + oidset_insert(gitmodules_oids, &oid); + } while (1); +} + +static void add_index_pack_keep_option(struct strvec *args) +{ + char hostname[HOST_NAME_MAX + 1]; + + if (xgethostname(hostname, sizeof(hostname))) + xsnprintf(hostname, sizeof(hostname), "localhost"); + strvec_pushf(args, "--keep=fetch-pack %"PRIuMAX " on %s", + (uintmax_t)getpid(), hostname); +} + +/* + * If packfile URIs were provided, pass a non-NULL pointer to index_pack_args. + * The strings to pass as the --index-pack-arg arguments to http-fetch will be + * stored there. (It must be freed by the caller.) + */ +static int get_pack(struct fetch_pack_args *args, + int xd[2], struct string_list *pack_lockfiles, + struct strvec *index_pack_args, + struct ref **sought, int nr_sought, + struct oidset *gitmodules_oids) +{ + struct async demux; + int do_keep = args->keep_pack; + const char *cmd_name; + struct pack_header header; + int pass_header = 0; + struct child_process cmd = CHILD_PROCESS_INIT; + int fsck_objects = 0; + int ret; + + memset(&demux, 0, sizeof(demux)); + if (use_sideband) { + /* xd[] is talking with upload-pack; subprocess reads from + * xd[0], spits out band#2 to stderr, and feeds us band#1 + * through demux->out. + */ + demux.proc = sideband_demux; + demux.data = xd; + demux.out = -1; + demux.isolate_sigpipe = 1; + if (start_async(&demux)) + die(_("fetch-pack: unable to fork off sideband demultiplexer")); + } + else + demux.out = xd[0]; + + if (!args->keep_pack && unpack_limit && !index_pack_args) { + + if (read_pack_header(demux.out, &header)) + die(_("protocol error: bad pack header")); + pass_header = 1; + if (ntohl(header.hdr_entries) < unpack_limit) + do_keep = 0; + else + do_keep = 1; + } + + if (alternate_shallow_file) { + strvec_push(&cmd.args, "--shallow-file"); + strvec_push(&cmd.args, alternate_shallow_file); + } + + if (fetch_fsck_objects >= 0 + ? fetch_fsck_objects + : transfer_fsck_objects >= 0 + ? transfer_fsck_objects + : 0) + fsck_objects = 1; + + if (do_keep || args->from_promisor || index_pack_args || fsck_objects) { + if (pack_lockfiles || fsck_objects) + cmd.out = -1; + cmd_name = "index-pack"; + strvec_push(&cmd.args, cmd_name); + strvec_push(&cmd.args, "--stdin"); + if (!args->quiet && !args->no_progress) + strvec_push(&cmd.args, "-v"); + if (args->use_thin_pack) + strvec_push(&cmd.args, "--fix-thin"); + if ((do_keep || index_pack_args) && (args->lock_pack || unpack_limit)) + add_index_pack_keep_option(&cmd.args); + if (!index_pack_args && args->check_self_contained_and_connected) + strvec_push(&cmd.args, "--check-self-contained-and-connected"); + else + /* + * We cannot perform any connectivity checks because + * not all packs have been downloaded; let the caller + * have this responsibility. + */ + args->check_self_contained_and_connected = 0; + + if (args->from_promisor) + /* + * create_promisor_file() may be called afterwards but + * we still need index-pack to know that this is a + * promisor pack. For example, if transfer.fsckobjects + * is true, index-pack needs to know that .gitmodules + * is a promisor object (so that it won't complain if + * it is missing). + */ + strvec_push(&cmd.args, "--promisor"); + } + else { + cmd_name = "unpack-objects"; + strvec_push(&cmd.args, cmd_name); + if (args->quiet || args->no_progress) + strvec_push(&cmd.args, "-q"); + args->check_self_contained_and_connected = 0; + } + + if (pass_header) + strvec_pushf(&cmd.args, "--pack_header=%"PRIu32",%"PRIu32, + ntohl(header.hdr_version), + ntohl(header.hdr_entries)); + if (fsck_objects) { + if (args->from_promisor || index_pack_args) + /* + * We cannot use --strict in index-pack because it + * checks both broken objects and links, but we only + * want to check for broken objects. + */ + strvec_push(&cmd.args, "--fsck-objects"); + else + strvec_pushf(&cmd.args, "--strict%s", + fsck_msg_types.buf); + } + + if (index_pack_args) { + int i; + + for (i = 0; i < cmd.args.nr; i++) + strvec_push(index_pack_args, cmd.args.v[i]); + } + + sigchain_push(SIGPIPE, SIG_IGN); + + cmd.in = demux.out; + cmd.git_cmd = 1; + if (start_command(&cmd)) + die(_("fetch-pack: unable to fork off %s"), cmd_name); + if (do_keep && (pack_lockfiles || fsck_objects)) { + int is_well_formed; + char *pack_lockfile = index_pack_lockfile(cmd.out, &is_well_formed); + + if (!is_well_formed) + die(_("fetch-pack: invalid index-pack output")); + if (pack_lockfile) + string_list_append_nodup(pack_lockfiles, pack_lockfile); + parse_gitmodules_oids(cmd.out, gitmodules_oids); + close(cmd.out); + } + + if (!use_sideband) + /* Closed by start_command() */ + xd[0] = -1; + + ret = finish_command(&cmd); + if (!ret || (args->check_self_contained_and_connected && ret == 1)) + args->self_contained_and_connected = + args->check_self_contained_and_connected && + ret == 0; + else + die(_("%s failed"), cmd_name); + if (use_sideband && finish_async(&demux)) + die(_("error in sideband demultiplexer")); + + sigchain_pop(SIGPIPE); + + /* + * Now that index-pack has succeeded, write the promisor file using the + * obtained .keep filename if necessary + */ + if (do_keep && pack_lockfiles && pack_lockfiles->nr && args->from_promisor) + create_promisor_file(pack_lockfiles->items[0].string, sought, nr_sought); + + return 0; +} + +static int ref_compare_name(const struct ref *a, const struct ref *b) +{ + return strcmp(a->name, b->name); +} + +DEFINE_LIST_SORT(static, sort_ref_list, struct ref, next); + +static int cmp_ref_by_name(const void *a_, const void *b_) +{ + const struct ref *a = *((const struct ref **)a_); + const struct ref *b = *((const struct ref **)b_); + return strcmp(a->name, b->name); +} + +static struct ref *do_fetch_pack(struct fetch_pack_args *args, + int fd[2], + const struct ref *orig_ref, + struct ref **sought, int nr_sought, + struct shallow_info *si, + struct string_list *pack_lockfiles) +{ + struct repository *r = the_repository; + struct ref *ref = copy_ref_list(orig_ref); + struct object_id oid; + const char *agent_feature; + size_t agent_len; + struct fetch_negotiator negotiator_alloc; + struct fetch_negotiator *negotiator; + + negotiator = &negotiator_alloc; + if (args->refetch) { + fetch_negotiator_init_noop(negotiator); + } else { + fetch_negotiator_init(r, negotiator); + } + + sort_ref_list(&ref, ref_compare_name); + QSORT(sought, nr_sought, cmp_ref_by_name); + + if ((agent_feature = server_feature_value("agent", &agent_len))) { + agent_supported = 1; + if (agent_len) + print_verbose(args, _("Server version is %.*s"), + (int)agent_len, agent_feature); + } + + if (!server_supports("session-id")) + advertise_sid = 0; + + if (server_supports("shallow")) + print_verbose(args, _("Server supports %s"), "shallow"); + else if (args->depth > 0 || is_repository_shallow(r)) + die(_("Server does not support shallow clients")); + if (args->depth > 0 || args->deepen_since || args->deepen_not) + args->deepen = 1; + if (server_supports("multi_ack_detailed")) { + print_verbose(args, _("Server supports %s"), "multi_ack_detailed"); + multi_ack = 2; + if (server_supports("no-done")) { + print_verbose(args, _("Server supports %s"), "no-done"); + if (args->stateless_rpc) + no_done = 1; + } + } + else if (server_supports("multi_ack")) { + print_verbose(args, _("Server supports %s"), "multi_ack"); + multi_ack = 1; + } + if (server_supports("side-band-64k")) { + print_verbose(args, _("Server supports %s"), "side-band-64k"); + use_sideband = 2; + } + else if (server_supports("side-band")) { + print_verbose(args, _("Server supports %s"), "side-band"); + use_sideband = 1; + } + if (server_supports("allow-tip-sha1-in-want")) { + print_verbose(args, _("Server supports %s"), "allow-tip-sha1-in-want"); + allow_unadvertised_object_request |= ALLOW_TIP_SHA1; + } + if (server_supports("allow-reachable-sha1-in-want")) { + print_verbose(args, _("Server supports %s"), "allow-reachable-sha1-in-want"); + allow_unadvertised_object_request |= ALLOW_REACHABLE_SHA1; + } + if (server_supports("thin-pack")) + print_verbose(args, _("Server supports %s"), "thin-pack"); + else + args->use_thin_pack = 0; + if (server_supports("no-progress")) + print_verbose(args, _("Server supports %s"), "no-progress"); + else + args->no_progress = 0; + if (server_supports("include-tag")) + print_verbose(args, _("Server supports %s"), "include-tag"); + else + args->include_tag = 0; + if (server_supports("ofs-delta")) + print_verbose(args, _("Server supports %s"), "ofs-delta"); + else + prefer_ofs_delta = 0; + + if (server_supports("filter")) { + server_supports_filtering = 1; + print_verbose(args, _("Server supports %s"), "filter"); + } else if (args->filter_options.choice) { + warning("filtering not recognized by server, ignoring"); + } + + if (server_supports("deepen-since")) { + print_verbose(args, _("Server supports %s"), "deepen-since"); + deepen_since_ok = 1; + } else if (args->deepen_since) + die(_("Server does not support --shallow-since")); + if (server_supports("deepen-not")) { + print_verbose(args, _("Server supports %s"), "deepen-not"); + deepen_not_ok = 1; + } else if (args->deepen_not) + die(_("Server does not support --shallow-exclude")); + if (server_supports("deepen-relative")) + print_verbose(args, _("Server supports %s"), "deepen-relative"); + else if (args->deepen_relative) + die(_("Server does not support --deepen")); + if (!server_supports_hash(the_hash_algo->name, NULL)) + die(_("Server does not support this repository's object format")); + + mark_complete_and_common_ref(negotiator, args, &ref); + filter_refs(args, &ref, sought, nr_sought); + if (!args->refetch && everything_local(args, &ref)) { + packet_flush(fd[1]); + goto all_done; + } + if (find_common(negotiator, args, fd, &oid, ref) < 0) + if (!args->keep_pack) + /* When cloning, it is not unusual to have + * no common commit. + */ + warning(_("no common commits")); + + if (args->stateless_rpc) + packet_flush(fd[1]); + if (args->deepen) + setup_alternate_shallow(&shallow_lock, &alternate_shallow_file, + NULL); + else if (si->nr_ours || si->nr_theirs) { + if (args->reject_shallow_remote) + die(_("source repository is shallow, reject to clone.")); + alternate_shallow_file = setup_temporary_shallow(si->shallow); + } else + alternate_shallow_file = NULL; + if (get_pack(args, fd, pack_lockfiles, NULL, sought, nr_sought, + &fsck_options.gitmodules_found)) + die(_("git fetch-pack: fetch failed.")); + if (fsck_finish(&fsck_options)) + die("fsck failed"); + + all_done: + if (negotiator) + negotiator->release(negotiator); + return ref; +} + +static void add_shallow_requests(struct strbuf *req_buf, + const struct fetch_pack_args *args) +{ + if (is_repository_shallow(the_repository)) + write_shallow_commits(req_buf, 1, NULL); + if (args->depth > 0) + packet_buf_write(req_buf, "deepen %d", args->depth); + if (args->deepen_since) { + timestamp_t max_age = approxidate(args->deepen_since); + packet_buf_write(req_buf, "deepen-since %"PRItime, max_age); + } + if (args->deepen_not) { + int i; + for (i = 0; i < args->deepen_not->nr; i++) { + struct string_list_item *s = args->deepen_not->items + i; + packet_buf_write(req_buf, "deepen-not %s", s->string); + } + } + if (args->deepen_relative) + packet_buf_write(req_buf, "deepen-relative\n"); +} + +static void add_wants(const struct ref *wants, struct strbuf *req_buf) +{ + int use_ref_in_want = server_supports_feature("fetch", "ref-in-want", 0); + + for ( ; wants ; wants = wants->next) { + const struct object_id *remote = &wants->old_oid; + 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(the_repository, remote)) != NULL) && + (o->flags & COMPLETE)) { + continue; + } + + if (!use_ref_in_want || wants->exact_oid) + packet_buf_write(req_buf, "want %s\n", oid_to_hex(remote)); + else + packet_buf_write(req_buf, "want-ref %s\n", wants->name); + } +} + +static void add_common(struct strbuf *req_buf, struct oidset *common) +{ + struct oidset_iter iter; + const struct object_id *oid; + oidset_iter_init(common, &iter); + + while ((oid = oidset_iter_next(&iter))) { + packet_buf_write(req_buf, "have %s\n", oid_to_hex(oid)); + } +} + +static int add_haves(struct fetch_negotiator *negotiator, + struct strbuf *req_buf, + int *haves_to_send) +{ + int haves_added = 0; + const struct object_id *oid; + + while ((oid = negotiator->next(negotiator))) { + packet_buf_write(req_buf, "have %s\n", oid_to_hex(oid)); + if (++haves_added >= *haves_to_send) + break; + } + + /* Increase haves to send on next round */ + *haves_to_send = next_flush(1, *haves_to_send); + + return haves_added; +} + +static void write_fetch_command_and_capabilities(struct strbuf *req_buf, + const struct string_list *server_options) +{ + const char *hash_name; + + ensure_server_supports_v2("fetch"); + packet_buf_write(req_buf, "command=fetch"); + if (server_supports_v2("agent")) + packet_buf_write(req_buf, "agent=%s", git_user_agent_sanitized()); + if (advertise_sid && server_supports_v2("session-id")) + packet_buf_write(req_buf, "session-id=%s", trace2_session_id()); + if (server_options && server_options->nr) { + int i; + ensure_server_supports_v2("server-option"); + for (i = 0; i < server_options->nr; i++) + packet_buf_write(req_buf, "server-option=%s", + server_options->items[i].string); + } + + if (server_feature_v2("object-format", &hash_name)) { + int hash_algo = hash_algo_by_name(hash_name); + if (hash_algo_by_ptr(the_hash_algo) != hash_algo) + die(_("mismatched algorithms: client %s; server %s"), + the_hash_algo->name, hash_name); + packet_buf_write(req_buf, "object-format=%s", the_hash_algo->name); + } else if (hash_algo_by_ptr(the_hash_algo) != GIT_HASH_SHA1) { + die(_("the server does not support algorithm '%s'"), + the_hash_algo->name); + } + packet_buf_delim(req_buf); +} + +static int send_fetch_request(struct fetch_negotiator *negotiator, int fd_out, + struct fetch_pack_args *args, + const struct ref *wants, struct oidset *common, + int *haves_to_send, int *in_vain, + int sideband_all, int seen_ack) +{ + int haves_added; + int done_sent = 0; + struct strbuf req_buf = STRBUF_INIT; + + write_fetch_command_and_capabilities(&req_buf, args->server_options); + + 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"); + if (sideband_all) + packet_buf_write(&req_buf, "sideband-all"); + + /* Add shallow-info and deepen request */ + if (server_supports_feature("fetch", "shallow", 0)) + add_shallow_requests(&req_buf, args); + else if (is_repository_shallow(the_repository) || args->deepen) + die(_("Server does not support shallow requests")); + + /* Add filter */ + send_filter(args, &req_buf, + server_supports_feature("fetch", "filter", 0)); + + if (server_supports_feature("fetch", "packfile-uris", 0)) { + int i; + struct strbuf to_send = STRBUF_INIT; + + for (i = 0; i < uri_protocols.nr; i++) { + const char *s = uri_protocols.items[i].string; + + if (!strcmp(s, "https") || !strcmp(s, "http")) { + if (to_send.len) + strbuf_addch(&to_send, ','); + strbuf_addstr(&to_send, s); + } + } + if (to_send.len) { + packet_buf_write(&req_buf, "packfile-uris %s", + to_send.buf); + strbuf_release(&to_send); + } + } + + /* add wants */ + add_wants(wants, &req_buf); + + /* Add all of the common commits we've found in previous rounds */ + add_common(&req_buf, common); + + haves_added = add_haves(negotiator, &req_buf, haves_to_send); + *in_vain += haves_added; + trace2_data_intmax("negotiation_v2", the_repository, "haves_added", haves_added); + trace2_data_intmax("negotiation_v2", the_repository, "in_vain", *in_vain); + if (!haves_added || (seen_ack && *in_vain >= MAX_IN_VAIN)) { + /* Send Done */ + packet_buf_write(&req_buf, "done\n"); + done_sent = 1; + } + + /* Send request */ + packet_buf_flush(&req_buf); + if (write_in_full(fd_out, req_buf.buf, req_buf.len) < 0) + die_errno(_("unable to write request to remote")); + + strbuf_release(&req_buf); + return done_sent; +} + +/* + * Processes a section header in a server's response and checks if it matches + * `section`. If the value of `peek` is 1, the header line will be peeked (and + * not consumed); if 0, the line will be consumed and the function will die if + * the section header doesn't match what was expected. + */ +static int process_section_header(struct packet_reader *reader, + const char *section, int peek) +{ + int ret = 0; + + if (packet_reader_peek(reader) == PACKET_READ_NORMAL && + !strcmp(reader->line, section)) + ret = 1; + + if (!peek) { + if (!ret) { + if (reader->line) + die(_("expected '%s', received '%s'"), + section, reader->line); + else + die(_("expected '%s'"), section); + } + packet_reader_read(reader); + } + + return ret; +} + +static int process_ack(struct fetch_negotiator *negotiator, + struct packet_reader *reader, + struct object_id *common_oid, + int *received_ready) +{ + while (packet_reader_read(reader) == PACKET_READ_NORMAL) { + const char *arg; + + if (!strcmp(reader->line, "NAK")) + continue; + + if (skip_prefix(reader->line, "ACK ", &arg)) { + if (!get_oid_hex(arg, common_oid)) { + struct commit *commit; + commit = lookup_commit(the_repository, common_oid); + if (negotiator) + negotiator->ack(negotiator, commit); + } + return 1; + } + + if (!strcmp(reader->line, "ready")) { + *received_ready = 1; + continue; + } + + die(_("unexpected acknowledgment line: '%s'"), reader->line); + } + + if (reader->status != PACKET_READ_FLUSH && + reader->status != PACKET_READ_DELIM) + die(_("error processing acks: %d"), reader->status); + + /* + * If an "acknowledgments" section is sent, a packfile is sent if and + * only if "ready" was sent in this section. The other sections + * ("shallow-info" and "wanted-refs") are sent only if a packfile is + * sent. Therefore, a DELIM is expected if "ready" is sent, and a FLUSH + * otherwise. + */ + if (*received_ready && reader->status != PACKET_READ_DELIM) + /* + * TRANSLATORS: The parameter will be 'ready', a protocol + * keyword. + */ + die(_("expected packfile to be sent after '%s'"), "ready"); + if (!*received_ready && reader->status != PACKET_READ_FLUSH) + /* + * TRANSLATORS: The parameter will be 'ready', a protocol + * keyword. + */ + die(_("expected no other sections to be sent after no '%s'"), "ready"); + + return 0; +} + +static void receive_shallow_info(struct fetch_pack_args *args, + struct packet_reader *reader, + struct oid_array *shallows, + struct shallow_info *si) +{ + int unshallow_received = 0; + + process_section_header(reader, "shallow-info", 0); + while (packet_reader_read(reader) == PACKET_READ_NORMAL) { + const char *arg; + struct object_id oid; + + if (skip_prefix(reader->line, "shallow ", &arg)) { + if (get_oid_hex(arg, &oid)) + die(_("invalid shallow line: %s"), reader->line); + oid_array_append(shallows, &oid); + continue; + } + if (skip_prefix(reader->line, "unshallow ", &arg)) { + if (get_oid_hex(arg, &oid)) + die(_("invalid unshallow line: %s"), reader->line); + if (!lookup_object(the_repository, &oid)) + die(_("object not found: %s"), reader->line); + /* make sure that it is parsed as shallow */ + if (!parse_object(the_repository, &oid)) + die(_("error in object: %s"), reader->line); + if (unregister_shallow(&oid)) + die(_("no shallow found: %s"), reader->line); + unshallow_received = 1; + continue; + } + die(_("expected shallow/unshallow, got %s"), reader->line); + } + + if (reader->status != PACKET_READ_FLUSH && + reader->status != PACKET_READ_DELIM) + die(_("error processing shallow info: %d"), reader->status); + + if (args->deepen || unshallow_received) { + /* + * Treat these as shallow lines caused by our depth settings. + * In v0, these lines cannot cause refs to be rejected; do the + * same. + */ + int i; + + for (i = 0; i < shallows->nr; i++) + register_shallow(the_repository, &shallows->oid[i]); + setup_alternate_shallow(&shallow_lock, &alternate_shallow_file, + NULL); + args->deepen = 1; + } else if (shallows->nr) { + /* + * Treat these as shallow lines caused by the remote being + * shallow. In v0, remote refs that reach these objects are + * rejected (unless --update-shallow is set); do the same. + */ + prepare_shallow_info(si, shallows); + if (si->nr_ours || si->nr_theirs) { + if (args->reject_shallow_remote) + die(_("source repository is shallow, reject to clone.")); + alternate_shallow_file = + setup_temporary_shallow(si->shallow); + } else + alternate_shallow_file = NULL; + } else { + alternate_shallow_file = NULL; + } +} + +static int cmp_name_ref(const void *name, const void *ref) +{ + return strcmp(name, (*(struct ref **)ref)->name); +} + +static void receive_wanted_refs(struct packet_reader *reader, + struct ref **sought, int nr_sought) +{ + process_section_header(reader, "wanted-refs", 0); + while (packet_reader_read(reader) == PACKET_READ_NORMAL) { + struct object_id oid; + const char *end; + struct ref **found; + + if (parse_oid_hex(reader->line, &oid, &end) || *end++ != ' ') + die(_("expected wanted-ref, got '%s'"), reader->line); + + found = bsearch(end, sought, nr_sought, sizeof(*sought), + cmp_name_ref); + if (!found) + die(_("unexpected wanted-ref: '%s'"), reader->line); + oidcpy(&(*found)->old_oid, &oid); + } + + if (reader->status != PACKET_READ_DELIM) + die(_("error processing wanted refs: %d"), reader->status); +} + +static void receive_packfile_uris(struct packet_reader *reader, + struct string_list *uris) +{ + process_section_header(reader, "packfile-uris", 0); + while (packet_reader_read(reader) == PACKET_READ_NORMAL) { + if (reader->pktlen < the_hash_algo->hexsz || + reader->line[the_hash_algo->hexsz] != ' ') + die("expected '<hash> <uri>', got: %s\n", reader->line); + + string_list_append(uris, reader->line); + } + if (reader->status != PACKET_READ_DELIM) + die("expected DELIM"); +} + +enum fetch_state { + FETCH_CHECK_LOCAL = 0, + FETCH_SEND_REQUEST, + FETCH_PROCESS_ACKS, + FETCH_GET_PACK, + FETCH_DONE, +}; + +static void do_check_stateless_delimiter(int stateless_rpc, + struct packet_reader *reader) +{ + check_stateless_delimiter(stateless_rpc, reader, + _("git fetch-pack: expected response end packet")); +} + +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, + struct oid_array *shallows, + struct shallow_info *si, + struct string_list *pack_lockfiles) +{ + struct repository *r = the_repository; + struct ref *ref = copy_ref_list(orig_ref); + enum fetch_state state = FETCH_CHECK_LOCAL; + struct oidset common = OIDSET_INIT; + struct packet_reader reader; + int in_vain = 0, negotiation_started = 0; + int negotiation_round = 0; + int haves_to_send = INITIAL_FLUSH; + struct fetch_negotiator negotiator_alloc; + struct fetch_negotiator *negotiator; + int seen_ack = 0; + struct object_id common_oid; + int received_ready = 0; + struct string_list packfile_uris = STRING_LIST_INIT_DUP; + int i; + struct strvec index_pack_args = STRVEC_INIT; + + negotiator = &negotiator_alloc; + if (args->refetch) + fetch_negotiator_init_noop(negotiator); + else + fetch_negotiator_init(r, negotiator); + + packet_reader_init(&reader, fd[0], NULL, 0, + PACKET_READ_CHOMP_NEWLINE | + PACKET_READ_DIE_ON_ERR_PACKET); + if (git_env_bool("GIT_TEST_SIDEBAND_ALL", 1) && + server_supports_feature("fetch", "sideband-all", 0)) { + reader.use_sideband = 1; + reader.me = "fetch-pack"; + } + + while (state != FETCH_DONE) { + switch (state) { + case FETCH_CHECK_LOCAL: + sort_ref_list(&ref, ref_compare_name); + QSORT(sought, nr_sought, cmp_ref_by_name); + + /* v2 supports these by default */ + allow_unadvertised_object_request |= ALLOW_REACHABLE_SHA1; + use_sideband = 2; + if (args->depth > 0 || args->deepen_since || args->deepen_not) + args->deepen = 1; + + /* Filter 'ref' by 'sought' and those that aren't local */ + mark_complete_and_common_ref(negotiator, args, &ref); + filter_refs(args, &ref, sought, nr_sought); + if (!args->refetch && everything_local(args, &ref)) + state = FETCH_DONE; + else + state = FETCH_SEND_REQUEST; + + mark_tips(negotiator, args->negotiation_tips); + for_each_cached_alternate(negotiator, + insert_one_alternate_object); + break; + case FETCH_SEND_REQUEST: + if (!negotiation_started) { + negotiation_started = 1; + trace2_region_enter("fetch-pack", + "negotiation_v2", + the_repository); + } + negotiation_round++; + trace2_region_enter_printf("negotiation_v2", "round", + the_repository, "%d", + negotiation_round); + if (send_fetch_request(negotiator, fd[1], args, ref, + &common, + &haves_to_send, &in_vain, + reader.use_sideband, + seen_ack)) { + trace2_region_leave_printf("negotiation_v2", "round", + the_repository, "%d", + negotiation_round); + state = FETCH_GET_PACK; + } + else + state = FETCH_PROCESS_ACKS; + break; + case FETCH_PROCESS_ACKS: + /* Process ACKs/NAKs */ + process_section_header(&reader, "acknowledgments", 0); + while (process_ack(negotiator, &reader, &common_oid, + &received_ready)) { + in_vain = 0; + seen_ack = 1; + oidset_insert(&common, &common_oid); + } + trace2_region_leave_printf("negotiation_v2", "round", + the_repository, "%d", + negotiation_round); + if (received_ready) { + /* + * Don't check for response delimiter; get_pack() will + * read the rest of this response. + */ + state = FETCH_GET_PACK; + } else { + do_check_stateless_delimiter(args->stateless_rpc, &reader); + state = FETCH_SEND_REQUEST; + } + break; + case FETCH_GET_PACK: + trace2_region_leave("fetch-pack", + "negotiation_v2", + the_repository); + trace2_data_intmax("negotiation_v2", the_repository, + "total_rounds", negotiation_round); + /* Check for shallow-info section */ + if (process_section_header(&reader, "shallow-info", 1)) + receive_shallow_info(args, &reader, shallows, si); + + if (process_section_header(&reader, "wanted-refs", 1)) + receive_wanted_refs(&reader, sought, nr_sought); + + /* get the pack(s) */ + if (git_env_bool("GIT_TRACE_REDACT", 1)) + reader.options |= PACKET_READ_REDACT_URI_PATH; + if (process_section_header(&reader, "packfile-uris", 1)) + receive_packfile_uris(&reader, &packfile_uris); + /* We don't expect more URIs. Reset to avoid expensive URI check. */ + reader.options &= ~PACKET_READ_REDACT_URI_PATH; + + process_section_header(&reader, "packfile", 0); + + /* + * this is the final request we'll make of the server; + * do a half-duplex shutdown to indicate that they can + * hang up as soon as the pack is sent. + */ + close(fd[1]); + fd[1] = -1; + + if (get_pack(args, fd, pack_lockfiles, + packfile_uris.nr ? &index_pack_args : NULL, + sought, nr_sought, &fsck_options.gitmodules_found)) + die(_("git fetch-pack: fetch failed.")); + do_check_stateless_delimiter(args->stateless_rpc, &reader); + + state = FETCH_DONE; + break; + case FETCH_DONE: + continue; + } + } + + for (i = 0; i < packfile_uris.nr; i++) { + int j; + struct child_process cmd = CHILD_PROCESS_INIT; + char packname[GIT_MAX_HEXSZ + 1]; + const char *uri = packfile_uris.items[i].string + + the_hash_algo->hexsz + 1; + + strvec_push(&cmd.args, "http-fetch"); + strvec_pushf(&cmd.args, "--packfile=%.*s", + (int) the_hash_algo->hexsz, + packfile_uris.items[i].string); + for (j = 0; j < index_pack_args.nr; j++) + strvec_pushf(&cmd.args, "--index-pack-arg=%s", + index_pack_args.v[j]); + strvec_push(&cmd.args, uri); + cmd.git_cmd = 1; + cmd.no_stdin = 1; + cmd.out = -1; + if (start_command(&cmd)) + die("fetch-pack: unable to spawn http-fetch"); + + if (read_in_full(cmd.out, packname, 5) < 0 || + memcmp(packname, "keep\t", 5)) + die("fetch-pack: expected keep then TAB at start of http-fetch output"); + + if (read_in_full(cmd.out, packname, + the_hash_algo->hexsz + 1) < 0 || + packname[the_hash_algo->hexsz] != '\n') + die("fetch-pack: expected hash then LF at end of http-fetch output"); + + packname[the_hash_algo->hexsz] = '\0'; + + parse_gitmodules_oids(cmd.out, &fsck_options.gitmodules_found); + + close(cmd.out); + + if (finish_command(&cmd)) + die("fetch-pack: unable to finish http-fetch"); + + if (memcmp(packfile_uris.items[i].string, packname, + the_hash_algo->hexsz)) + die("fetch-pack: pack downloaded from %s does not match expected hash %.*s", + uri, (int) the_hash_algo->hexsz, + packfile_uris.items[i].string); + + string_list_append_nodup(pack_lockfiles, + xstrfmt("%s/pack/pack-%s.keep", + get_object_directory(), + packname)); + } + string_list_clear(&packfile_uris, 0); + strvec_clear(&index_pack_args); + + if (fsck_finish(&fsck_options)) + die("fsck failed"); + + if (negotiator) + negotiator->release(negotiator); + + oidset_clear(&common); + return ref; +} + +static int fetch_pack_config_cb(const char *var, const char *value, + const struct config_context *ctx, void *cb) +{ + if (strcmp(var, "fetch.fsck.skiplist") == 0) { + const char *path; + + if (git_config_pathname(&path, var, value)) + return 1; + strbuf_addf(&fsck_msg_types, "%cskiplist=%s", + fsck_msg_types.len ? ',' : '=', path); + free((char *)path); + return 0; + } + + if (skip_prefix(var, "fetch.fsck.", &var)) { + if (is_valid_msg_type(var, value)) + strbuf_addf(&fsck_msg_types, "%c%s=%s", + fsck_msg_types.len ? ',' : '=', var, value); + else + warning("Skipping unknown msg id '%s'", var); + return 0; + } + + return git_default_config(var, value, ctx, cb); +} + +static void fetch_pack_config(void) +{ + git_config_get_int("fetch.unpacklimit", &fetch_unpack_limit); + git_config_get_int("transfer.unpacklimit", &transfer_unpack_limit); + git_config_get_bool("repack.usedeltabaseoffset", &prefer_ofs_delta); + git_config_get_bool("fetch.fsckobjects", &fetch_fsck_objects); + git_config_get_bool("transfer.fsckobjects", &transfer_fsck_objects); + git_config_get_bool("transfer.advertisesid", &advertise_sid); + if (!uri_protocols.nr) { + char *str; + + if (!git_config_get_string("fetch.uriprotocols", &str) && str) { + string_list_split(&uri_protocols, str, ',', -1); + free(str); + } + } + + git_config(fetch_pack_config_cb, NULL); +} + +static void fetch_pack_setup(void) +{ + static int did_setup; + if (did_setup) + return; + fetch_pack_config(); + if (0 <= fetch_unpack_limit) + unpack_limit = fetch_unpack_limit; + else if (0 <= transfer_unpack_limit) + unpack_limit = transfer_unpack_limit; + did_setup = 1; +} + +static int remove_duplicates_in_refs(struct ref **ref, int nr) +{ + struct string_list names = STRING_LIST_INIT_NODUP; + int src, dst; + + for (src = dst = 0; src < nr; src++) { + struct string_list_item *item; + item = string_list_insert(&names, ref[src]->name); + if (item->util) + continue; /* already have it */ + item->util = ref[src]; + if (src != dst) + ref[dst] = ref[src]; + dst++; + } + for (src = dst; src < nr; src++) + ref[src] = NULL; + string_list_clear(&names, 0); + return dst; +} + +static void update_shallow(struct fetch_pack_args *args, + struct ref **sought, int nr_sought, + struct shallow_info *si) +{ + struct oid_array ref = OID_ARRAY_INIT; + int *status; + int i; + + if (args->deepen && alternate_shallow_file) { + if (*alternate_shallow_file == '\0') { /* --unshallow */ + unlink_or_warn(git_path_shallow(the_repository)); + rollback_shallow_file(the_repository, &shallow_lock); + } else + commit_shallow_file(the_repository, &shallow_lock); + alternate_shallow_file = NULL; + return; + } + + if (!si->shallow || !si->shallow->nr) + return; + + if (args->cloning) { + /* + * remote is shallow, but this is a clone, there are + * no objects in repo to worry about. Accept any + * shallow points that exist in the pack (iow in repo + * after get_pack() and reprepare_packed_git()) + */ + struct oid_array extra = OID_ARRAY_INIT; + struct object_id *oid = si->shallow->oid; + for (i = 0; i < si->shallow->nr; i++) + if (repo_has_object_file(the_repository, &oid[i])) + oid_array_append(&extra, &oid[i]); + if (extra.nr) { + setup_alternate_shallow(&shallow_lock, + &alternate_shallow_file, + &extra); + commit_shallow_file(the_repository, &shallow_lock); + alternate_shallow_file = NULL; + } + oid_array_clear(&extra); + return; + } + + if (!si->nr_ours && !si->nr_theirs) + return; + + remove_nonexistent_theirs_shallow(si); + if (!si->nr_ours && !si->nr_theirs) + return; + for (i = 0; i < nr_sought; i++) + oid_array_append(&ref, &sought[i]->old_oid); + si->ref = &ref; + + if (args->update_shallow) { + /* + * remote is also shallow, .git/shallow may be updated + * so all refs can be accepted. Make sure we only add + * shallow roots that are actually reachable from new + * refs. + */ + struct oid_array extra = OID_ARRAY_INIT; + struct object_id *oid = si->shallow->oid; + assign_shallow_commits_to_refs(si, NULL, NULL); + if (!si->nr_ours && !si->nr_theirs) { + oid_array_clear(&ref); + return; + } + for (i = 0; i < si->nr_ours; i++) + oid_array_append(&extra, &oid[si->ours[i]]); + for (i = 0; i < si->nr_theirs; i++) + oid_array_append(&extra, &oid[si->theirs[i]]); + setup_alternate_shallow(&shallow_lock, + &alternate_shallow_file, + &extra); + commit_shallow_file(the_repository, &shallow_lock); + oid_array_clear(&extra); + oid_array_clear(&ref); + alternate_shallow_file = NULL; + return; + } + + /* + * remote is also shallow, check what ref is safe to update + * without updating .git/shallow + */ + CALLOC_ARRAY(status, nr_sought); + assign_shallow_commits_to_refs(si, NULL, status); + if (si->nr_ours || si->nr_theirs) { + for (i = 0; i < nr_sought; i++) + if (status[i]) + sought[i]->status = REF_STATUS_REJECT_SHALLOW; + } + free(status); + oid_array_clear(&ref); +} + +static const struct object_id *iterate_ref_map(void *cb_data) +{ + struct ref **rm = cb_data; + struct ref *ref = *rm; + + if (!ref) + return NULL; + *rm = ref->next; + return &ref->old_oid; +} + +struct ref *fetch_pack(struct fetch_pack_args *args, + int fd[], + const struct ref *ref, + struct ref **sought, int nr_sought, + struct oid_array *shallow, + struct string_list *pack_lockfiles, + enum protocol_version version) +{ + struct ref *ref_cpy; + struct shallow_info si; + struct oid_array shallows_scratch = OID_ARRAY_INIT; + + fetch_pack_setup(); + if (nr_sought) + nr_sought = remove_duplicates_in_refs(sought, nr_sought); + + if (version != protocol_v2 && !ref) { + packet_flush(fd[1]); + die(_("no matching remote head")); + } + if (version == protocol_v2) { + if (shallow->nr) + BUG("Protocol V2 does not provide shallows at this point in the fetch"); + memset(&si, 0, sizeof(si)); + ref_cpy = do_fetch_pack_v2(args, fd, ref, sought, nr_sought, + &shallows_scratch, &si, + pack_lockfiles); + } else { + prepare_shallow_info(&si, shallow); + ref_cpy = do_fetch_pack(args, fd, ref, sought, nr_sought, + &si, pack_lockfiles); + } + reprepare_packed_git(the_repository); + + if (!args->cloning && args->deepen) { + struct check_connected_options opt = CHECK_CONNECTED_INIT; + struct ref *iterator = ref_cpy; + opt.shallow_file = alternate_shallow_file; + if (args->deepen) + opt.is_deepening_fetch = 1; + if (check_connected(iterate_ref_map, &iterator, &opt)) { + error(_("remote did not send all necessary objects")); + free_refs(ref_cpy); + ref_cpy = NULL; + rollback_shallow_file(the_repository, &shallow_lock); + goto cleanup; + } + args->connectivity_checked = 1; + } + + update_shallow(args, sought, nr_sought, &si); +cleanup: + clear_shallow_info(&si); + oid_array_clear(&shallows_scratch); + return ref_cpy; +} + +static int add_to_object_array(const struct object_id *oid, void *data) +{ + struct object_array *a = data; + + add_object_array(lookup_object(the_repository, oid), "", a); + return 0; +} + +static void clear_common_flag(struct oidset *s) +{ + struct oidset_iter iter; + const struct object_id *oid; + oidset_iter_init(s, &iter); + + while ((oid = oidset_iter_next(&iter))) { + struct object *obj = lookup_object(the_repository, oid); + obj->flags &= ~COMMON; + } +} + +void negotiate_using_fetch(const struct oid_array *negotiation_tips, + const struct string_list *server_options, + int stateless_rpc, + int fd[], + struct oidset *acked_commits) +{ + struct fetch_negotiator negotiator; + struct packet_reader reader; + struct object_array nt_object_array = OBJECT_ARRAY_INIT; + struct strbuf req_buf = STRBUF_INIT; + int haves_to_send = INITIAL_FLUSH; + int in_vain = 0; + int seen_ack = 0; + int last_iteration = 0; + int negotiation_round = 0; + timestamp_t min_generation = GENERATION_NUMBER_INFINITY; + + fetch_negotiator_init(the_repository, &negotiator); + mark_tips(&negotiator, negotiation_tips); + + packet_reader_init(&reader, fd[0], NULL, 0, + PACKET_READ_CHOMP_NEWLINE | + PACKET_READ_DIE_ON_ERR_PACKET); + + oid_array_for_each((struct oid_array *) negotiation_tips, + add_to_object_array, + &nt_object_array); + + trace2_region_enter("fetch-pack", "negotiate_using_fetch", the_repository); + while (!last_iteration) { + int haves_added; + struct object_id common_oid; + int received_ready = 0; + + negotiation_round++; + + trace2_region_enter_printf("negotiate_using_fetch", "round", + the_repository, "%d", + negotiation_round); + strbuf_reset(&req_buf); + write_fetch_command_and_capabilities(&req_buf, server_options); + + packet_buf_write(&req_buf, "wait-for-done"); + + haves_added = add_haves(&negotiator, &req_buf, &haves_to_send); + in_vain += haves_added; + if (!haves_added || (seen_ack && in_vain >= MAX_IN_VAIN)) + last_iteration = 1; + + trace2_data_intmax("negotiate_using_fetch", the_repository, + "haves_added", haves_added); + trace2_data_intmax("negotiate_using_fetch", the_repository, + "in_vain", in_vain); + + /* Send request */ + packet_buf_flush(&req_buf); + if (write_in_full(fd[1], req_buf.buf, req_buf.len) < 0) + die_errno(_("unable to write request to remote")); + + /* Process ACKs/NAKs */ + process_section_header(&reader, "acknowledgments", 0); + while (process_ack(&negotiator, &reader, &common_oid, + &received_ready)) { + struct commit *commit = lookup_commit(the_repository, + &common_oid); + if (commit) { + timestamp_t generation; + + parse_commit_or_die(commit); + commit->object.flags |= COMMON; + generation = commit_graph_generation(commit); + if (generation < min_generation) + min_generation = generation; + } + in_vain = 0; + seen_ack = 1; + oidset_insert(acked_commits, &common_oid); + } + if (received_ready) + die(_("unexpected 'ready' from remote")); + else + do_check_stateless_delimiter(stateless_rpc, &reader); + if (can_all_from_reach_with_flag(&nt_object_array, COMMON, + REACH_SCRATCH, 0, + min_generation)) + last_iteration = 1; + trace2_region_leave_printf("negotiation", "round", + the_repository, "%d", + negotiation_round); + } + trace2_region_enter("fetch-pack", "negotiate_using_fetch", the_repository); + trace2_data_intmax("negotiate_using_fetch", the_repository, + "total_rounds", negotiation_round); + clear_common_flag(acked_commits); + strbuf_release(&req_buf); +} + +int report_unmatched_refs(struct ref **sought, int nr_sought) +{ + int i, ret = 0; + + for (i = 0; i < nr_sought; i++) { + if (!sought[i]) + continue; + switch (sought[i]->match_status) { + case REF_MATCHED: + continue; + case REF_NOT_MATCHED: + error(_("no such remote ref %s"), sought[i]->name); + break; + case REF_UNADVERTISED_NOT_ALLOWED: + error(_("Server does not allow request for unadvertised object %s"), + sought[i]->name); + break; + } + ret = 1; + } + return ret; +} |