[PATCH v4 1/3] push: add reflog check for "--force-if-includes"
- From
Srinidhi Kaushik <shrinidhi.kaushik@gmail.com>
- Date
- Sep 19, 2020, 17:03 UTC
- Message-ID
- <20200919170316.5310-2-shrinidhi.kaushik@gmail.com>
- In-Reply-To
- <20200919170316.5310-1-shrinidhi.kaushik@gmail.com>
Adds a check to verify if the remote-tracking ref of the local branch is reachable from one of its "reflog" entries.
When a local branch that is based on a remote ref, has been rewound and is to be force pushed on the remote, "--force-if-includes" runs a check that ensures any updates to remote-tracking refs that may have happened (by push from another repository) in-between the time of the last checkout, and right before the time of push, have been integrated locally before allowing a forced updated.
A new field "use_force_if_includes" has been added to "push_cas_option", which is set to "1" when "--force-if-includes" is specified as an argument in the command line or set as a configuration option.
The struct "ref" has two new bit-fields:
- if_includes:
Set when we have to run the new check on the ref, and the remote
ref was marked as "use_tracking" or "use_tracking_for_rest" by
compare-and-swap (if the "the remote tip must be at the expected
commit" condition is not specified); "apply_push_cas()" has been
updated to check if this field is set and run the check. - unreachable:
Set if the ref is unreachable from any of the "reflog" entries of
its local counterpart."REF_STATUS_REJECT_REMOTE_UPDATED" has been added to the "status" enum to imply that the ref failed the check; "case" statements in "send-pack", "transport" and "transport-helper" have been updated accordingly to catch this status when set.
When "--force-with-includes" is used along with "--force-with-lease", the check runs only for refs marked as "if_includes". If the option is passed without specifying "--force-with-lease", or specified along with "--force-with-lease=<refname>:<expect>" it is a "no-op".
Signed-off-by: Srinidhi Kaushik <shrinidhi.kaushik@gmail.com> --- builtin/send-pack.c | 5 +++ remote.c | 92 ++++++++++++++++++++++++++++++++++++++++++++- remote.h | 6 ++- send-pack.c | 1 + transport-helper.c | 5 +++ transport.c | 6 +++ 6 files changed, 112 insertions(+), 3 deletions(-)
diff --git a/builtin/send-pack.c b/builtin/send-pack.c index 2b9610f121..4d76727edb 100644 --- a/builtin/send-pack.c +++ b/builtin/send-pack.c @@ -69,6 +69,11 @@ static void print_helper_status(struct ref *ref) msg = "stale info"; break; + case REF_STATUS_REJECT_REMOTE_UPDATED: + res = "error"; + msg = "remote ref updated since checkout"; + break; + case REF_STATUS_REJECT_ALREADY_EXISTS: res = "error"; msg = "already exists"; diff --git a/remote.c b/remote.c index eafc14cbe7..60d681a885 100644 --- a/remote.c +++ b/remote.c @@ -1471,12 +1471,23 @@ void set_ref_status_for_push(struct ref *remote_refs, int send_mirror, * with the remote-tracking branch to find the value * to expect, but we did not have such a tracking * branch. + * + * If the tip of the remote-tracking ref is unreachable + * from any reflog entry of its local ref indicating a + * possible update since checkout; reject the push. */ if (ref->expect_old_sha1) { if (!oideq(&ref->old_oid, &ref->old_oid_expect)) reject_reason = REF_STATUS_REJECT_STALE; + else if (ref->if_includes && ref->unreachable) + reject_reason = + REF_STATUS_REJECT_REMOTE_UPDATED; else - /* If the ref isn't stale then force the update. */ + /* + * If the ref isn't stale, and is reachable + * from from one of the reflog entries of + * the local branch, force the update. + */ force_ref_update = 1; } @@ -2268,6 +2279,70 @@ static int remote_tracking(struct remote *remote, const char *refname, return 0; } +/* Checks if the ref exists in the reflog entry. */ +static int reflog_entry_exists(struct object_id *o_oid, + struct object_id *n_oid, + const char *ident, timestamp_t timestamp, + int tz, const char *message, void *cb_data) +{ + struct object_id *remote_oid = cb_data; + return oideq(n_oid, remote_oid); +} + +/* Checks if the ref is reachable from the reflog entry. */ +static int reflog_entry_reachable(struct object_id *o_oid, + struct object_id *n_oid, + const char *ident, timestamp_t timestamp, + int tz, const char *message, void *cb_data) +{ + struct commit *local_commit; + struct commit *remote_commit = cb_data; + + local_commit = lookup_commit_reference(the_repository, n_oid); + if (local_commit) + return in_merge_bases(remote_commit, local_commit); + + return 0; +} + +/* + * Iterate through he reflog entries of the local branch to check + * if the remote-tracking ref exists in on of the entries; if not, + * go through the entries once more, but this time check if the + * remote-tracking ref is reachable from any of the entries. + */ +static int is_reachable_in_reflog(const char *local_ref_name, + const struct object_id *remote_oid) +{ + struct commit *remote_commit; + + if (for_each_reflog_ent_reverse(local_ref_name, reflog_entry_exists, + (struct object_id *)remote_oid)) + return 1; + + remote_commit = lookup_commit_reference(the_repository, remote_oid); + if (remote_commit) + return for_each_reflog_ent_reverse(local_ref_name, + reflog_entry_reachable, + remote_commit); + return 0; +} + +/* + * Check for reachability of a remote-tracking + * ref in the reflog entries of its local ref. + */ +static void check_if_includes_upstream(struct ref *remote_ref) +{ + struct ref *local_ref = get_local_ref(remote_ref->name); + + if (!local_ref) + return; + + if (!is_reachable_in_reflog(local_ref->name, &remote_ref->old_oid)) + remote_ref->unreachable = 1; +} + static void apply_cas(struct push_cas_option *cas, struct remote *remote, struct ref *ref) @@ -2284,6 +2359,8 @@ static void apply_cas(struct push_cas_option *cas, oidcpy(&ref->old_oid_expect, &entry->expect); else if (remote_tracking(remote, ref->name, &ref->old_oid_expect)) oidclr(&ref->old_oid_expect); + else + ref->if_includes = cas->use_force_if_includes; return; } @@ -2294,6 +2371,8 @@ static void apply_cas(struct push_cas_option *cas, ref->expect_old_sha1 = 1; if (remote_tracking(remote, ref->name, &ref->old_oid_expect)) oidclr(&ref->old_oid_expect); + else + ref->if_includes = cas->use_force_if_includes; } void apply_push_cas(struct push_cas_option *cas, @@ -2301,6 +2380,15 @@ void apply_push_cas(struct push_cas_option *cas, struct ref *remote_refs) { struct ref *ref; - for (ref = remote_refs; ref; ref = ref->next) + for (ref = remote_refs; ref; ref = ref->next) { apply_cas(cas, remote, ref); + + /* + * If "compare-and-swap" is in "use_tracking[_for_rest]" + * mode, and if "--foce-if-includes" was specified, run + * the check. + */ + if (ref->if_includes) + check_if_includes_upstream(ref); + } } diff --git a/remote.h b/remote.h index 5e3ea5a26d..38ab8539e2 100644 --- a/remote.h +++ b/remote.h @@ -104,7 +104,9 @@ struct ref { forced_update:1, expect_old_sha1:1, exact_oid:1, - deletion:1; + deletion:1, + if_includes:1, /* If "--force-with-includes" was specified. */ + unreachable:1; /* For "if_includes"; unreachable in reflog. */ enum { REF_NOT_MATCHED = 0, /* initial value */ @@ -134,6 +136,7 @@ struct ref { REF_STATUS_REJECT_NEEDS_FORCE, REF_STATUS_REJECT_STALE, REF_STATUS_REJECT_SHALLOW, + REF_STATUS_REJECT_REMOTE_UPDATED, REF_STATUS_UPTODATE, REF_STATUS_REMOTE_REJECT, REF_STATUS_EXPECTING_REPORT, @@ -332,6 +335,7 @@ struct ref *get_stale_heads(struct refspec *rs, struct ref *fetch_map); struct push_cas_option { unsigned use_tracking_for_rest:1; + unsigned use_force_if_includes:1; struct push_cas { struct object_id expect; unsigned use_tracking:1; diff --git a/send-pack.c b/send-pack.c index 632f1580ca..956306e8e8 100644 --- a/send-pack.c +++ b/send-pack.c @@ -240,6 +240,7 @@ static int check_to_send_update(const struct ref *ref, const struct send_pack_ar case REF_STATUS_REJECT_FETCH_FIRST: case REF_STATUS_REJECT_NEEDS_FORCE: case REF_STATUS_REJECT_STALE: + case REF_STATUS_REJECT_REMOTE_UPDATED: case REF_STATUS_REJECT_NODELETE: return CHECK_REF_STATUS_REJECTED; case REF_STATUS_UPTODATE: diff --git a/transport-helper.c b/transport-helper.c index c52c99d829..e547e21199 100644 --- a/transport-helper.c +++ b/transport-helper.c @@ -779,6 +779,10 @@ static int push_update_ref_status(struct strbuf *buf, status = REF_STATUS_REJECT_STALE; FREE_AND_NULL(msg); } + else if (!strcmp(msg, "remote ref updated since checkout")) { + status = REF_STATUS_REJECT_REMOTE_UPDATED; + FREE_AND_NULL(msg); + } else if (!strcmp(msg, "forced update")) { forced = 1; FREE_AND_NULL(msg); @@ -897,6 +901,7 @@ static int push_refs_with_push(struct transport *transport, case REF_STATUS_REJECT_NONFASTFORWARD: case REF_STATUS_REJECT_STALE: case REF_STATUS_REJECT_ALREADY_EXISTS: + case REF_STATUS_REJECT_REMOTE_UPDATED: if (atomic) { reject_atomic_push(remote_refs, mirror); string_list_clear(&cas_options, 0); diff --git a/transport.c b/transport.c index 43e24bf1e5..99fe6233a3 100644 --- a/transport.c +++ b/transport.c @@ -567,6 +567,11 @@ static int print_one_push_status(struct ref *ref, const char *dest, int count, print_ref_status('!', "[rejected]", ref, ref->peer_ref, "stale info", porcelain, summary_width); break; + case REF_STATUS_REJECT_REMOTE_UPDATED: + print_ref_status('!', "[rejected]", ref, ref->peer_ref, + "remote ref updated since checkout", + porcelain, summary_width); + break; case REF_STATUS_REJECT_SHALLOW: print_ref_status('!', "[rejected]", ref, ref->peer_ref, "new shallow roots not allowed", @@ -1101,6 +1106,7 @@ static int run_pre_push_hook(struct transport *transport, if (!r->peer_ref) continue; if (r->status == REF_STATUS_REJECT_NONFASTFORWARD) continue; if (r->status == REF_STATUS_REJECT_STALE) continue; + if (r->status == REF_STATUS_REJECT_REMOTE_UPDATED) continue; if (r->status == REF_STATUS_UPTODATE) continue; strbuf_reset(&buf);
-- 2.28.0