diff --git a/Documentation/githooks.txt b/Documentation/githooks.txt index ee9b92c90d..06e997131b 100644 --- a/Documentation/githooks.txt +++ b/Documentation/githooks.txt @@ -486,7 +486,7 @@ reference-transaction This hook is invoked by any Git command that performs reference updates. It executes whenever a reference transaction is prepared, committed or aborted and may thus get called multiple times. The hook -does not cover symbolic references (but that may change in the future). +also supports symbolic reference updates. The hook takes exactly one argument, which is the current state the given reference transaction is in: @@ -503,16 +503,20 @@ given reference transaction is in: For each reference update that was added to the transaction, the hook receives on standard input a line of the format: - SP SP LF + SP SP LF -where `` is the old object name passed into the reference -transaction, `` is the new object name to be stored in the +where `` is the old object name passed into the reference +transaction, `` is the new object name to be stored in the ref and `` is the full name of the ref. When force updating the reference regardless of its current value or when the reference is -to be created anew, `` is the all-zeroes object name. To +to be created anew, `` is the all-zeroes object name. To distinguish these cases, you can inspect the current value of `` via `git rev-parse`. +For symbolic reference updates the `` and `` +fields could denote references instead of objects. A reference will be +denoted with a 'ref:' prefix, like `ref:`. + The exit status of the hook is ignored for any state except for the "prepared" state. In the "prepared" state, a non-zero exit status will cause the transaction to be aborted. The hook will not be called with diff --git a/branch.c b/branch.c index e4a738fc7b..48af4c3ceb 100644 --- a/branch.c +++ b/branch.c @@ -627,7 +627,7 @@ void create_branch(struct repository *r, if (!transaction || ref_transaction_update(transaction, ref.buf, &oid, forcing ? NULL : null_oid(), - 0, msg, &err) || + NULL, NULL, 0, msg, &err) || ref_transaction_commit(transaction, &err)) die("%s", err.buf); ref_transaction_free(transaction); diff --git a/builtin/branch.c b/builtin/branch.c index dd3e3a7dc0..4491f7a20c 100644 --- a/builtin/branch.c +++ b/builtin/branch.c @@ -555,7 +555,7 @@ static int replace_each_worktree_head_symref(struct worktree **worktrees, continue; refs = get_worktree_ref_store(worktrees[i]); - if (refs_create_symref(refs, "HEAD", newref, logmsg)) + if (refs_update_symref(refs, "HEAD", newref, logmsg)) ret = error(_("HEAD of working tree %s is not updated"), worktrees[i]->path); } diff --git a/builtin/fast-import.c b/builtin/fast-import.c index dc5a9d32dd..297dfb91a1 100644 --- a/builtin/fast-import.c +++ b/builtin/fast-import.c @@ -1634,7 +1634,7 @@ static int update_branch(struct branch *b) transaction = ref_transaction_begin(&err); if (!transaction || ref_transaction_update(transaction, b->name, &b->oid, &old_oid, - 0, msg, &err) || + NULL, NULL, 0, msg, &err) || ref_transaction_commit(transaction, &err)) { ref_transaction_free(transaction); error("%s", err.buf); @@ -1675,7 +1675,8 @@ static void dump_tags(void) strbuf_addf(&ref_name, "refs/tags/%s", t->name); if (ref_transaction_update(transaction, ref_name.buf, - &t->oid, NULL, 0, msg, &err)) { + &t->oid, NULL, NULL, NULL, + 0, msg, &err)) { failure |= error("%s", err.buf); goto cleanup; } diff --git a/builtin/fetch.c b/builtin/fetch.c index 5857d860db..66840b7c5b 100644 --- a/builtin/fetch.c +++ b/builtin/fetch.c @@ -668,7 +668,7 @@ static int s_update_ref(const char *action, ret = ref_transaction_update(transaction, ref->name, &ref->new_oid, check_old ? &ref->old_oid : NULL, - 0, msg, &err); + NULL, NULL, 0, msg, &err); if (ret) { ret = STORE_REF_ERROR_OTHER; goto out; diff --git a/builtin/receive-pack.c b/builtin/receive-pack.c index e8d7df14b6..b150ef39a8 100644 --- a/builtin/receive-pack.c +++ b/builtin/receive-pack.c @@ -1595,6 +1595,7 @@ static const char *update(struct command *cmd, struct shallow_info *si) if (ref_transaction_update(transaction, namespaced_name, new_oid, old_oid, + NULL, NULL, 0, "push", &err)) { rp_error("%s", err.buf); diff --git a/builtin/replace.c b/builtin/replace.c index da59600ad2..7690687b0e 100644 --- a/builtin/replace.c +++ b/builtin/replace.c @@ -201,7 +201,7 @@ static int replace_object_oid(const char *object_ref, transaction = ref_transaction_begin(&err); if (!transaction || ref_transaction_update(transaction, ref.buf, repl, &prev, - 0, NULL, &err) || + NULL, NULL, 0, NULL, &err) || ref_transaction_commit(transaction, &err)) res = error("%s", err.buf); diff --git a/builtin/tag.c b/builtin/tag.c index 9a33cb50b4..40a65fdebc 100644 --- a/builtin/tag.c +++ b/builtin/tag.c @@ -660,6 +660,7 @@ int cmd_tag(int argc, const char **argv, const char *prefix) transaction = ref_transaction_begin(&err); if (!transaction || ref_transaction_update(transaction, ref.buf, &object, &prev, + NULL, NULL, create_reflog ? REF_FORCE_CREATE_REFLOG : 0, reflog_msg.buf, &err) || ref_transaction_commit(transaction, &err)) { diff --git a/builtin/update-ref.c b/builtin/update-ref.c index e46afbc46d..21fdbf6ac8 100644 --- a/builtin/update-ref.c +++ b/builtin/update-ref.c @@ -204,6 +204,7 @@ static void parse_cmd_update(struct ref_transaction *transaction, if (ref_transaction_update(transaction, refname, &new_oid, have_old ? &old_oid : NULL, + NULL, NULL, update_flags | create_reflog_flag, msg, &err)) die("%s", err.buf); diff --git a/builtin/worktree.c b/builtin/worktree.c index 7c6c72536b..480202c517 100644 --- a/builtin/worktree.c +++ b/builtin/worktree.c @@ -517,7 +517,7 @@ static int add_worktree(const char *path, const char *refname, ret = refs_update_ref(wt_refs, NULL, "HEAD", &commit->object.oid, NULL, 0, UPDATE_REFS_MSG_ON_ERR); else - ret = refs_create_symref(wt_refs, "HEAD", symref.buf, NULL); + ret = refs_update_symref(wt_refs, "HEAD", symref.buf, NULL); if (ret) goto done; diff --git a/refs.c b/refs.c index 55d2e0b2cb..fa5471d219 100644 --- a/refs.c +++ b/refs.c @@ -1217,6 +1217,8 @@ void ref_transaction_free(struct ref_transaction *transaction) for (i = 0; i < transaction->nr; i++) { free(transaction->updates[i]->msg); + free((char *)transaction->updates[i]->new_target); + free((char *)transaction->updates[i]->old_target); free(transaction->updates[i]); } free(transaction->updates); @@ -1228,6 +1230,7 @@ struct ref_update *ref_transaction_add_update( const char *refname, unsigned int flags, const struct object_id *new_oid, const struct object_id *old_oid, + const char *new_target, const char *old_target, const char *msg) { struct ref_update *update; @@ -1235,16 +1238,24 @@ struct ref_update *ref_transaction_add_update( if (transaction->state != REF_TRANSACTION_OPEN) BUG("update called for transaction that is not open"); + if (old_oid && old_target) + BUG("only one of old_oid and old_target should be non NULL"); + if (new_oid && new_target) + BUG("only one of new_oid and new_target should be non NULL"); + FLEX_ALLOC_STR(update, refname, refname); ALLOC_GROW(transaction->updates, transaction->nr + 1, transaction->alloc); transaction->updates[transaction->nr++] = update; update->flags = flags; - if (flags & REF_HAVE_NEW) + update->new_target = xstrdup_or_null(new_target); + update->old_target = xstrdup_or_null(old_target); + if ((flags & REF_HAVE_NEW) && new_oid) oidcpy(&update->new_oid, new_oid); - if (flags & REF_HAVE_OLD) + if ((flags & REF_HAVE_OLD) && old_oid) oidcpy(&update->old_oid, old_oid); + update->msg = normalize_reflog_message(msg); return update; } @@ -1253,6 +1264,8 @@ int ref_transaction_update(struct ref_transaction *transaction, const char *refname, const struct object_id *new_oid, const struct object_id *old_oid, + const char *new_target, + const char *old_target, unsigned int flags, const char *msg, struct strbuf *err) { @@ -1278,9 +1291,11 @@ int ref_transaction_update(struct ref_transaction *transaction, flags &= REF_TRANSACTION_UPDATE_ALLOWED_FLAGS; flags |= (new_oid ? REF_HAVE_NEW : 0) | (old_oid ? REF_HAVE_OLD : 0); + flags |= (new_target ? REF_HAVE_NEW : 0) | (old_target ? REF_HAVE_OLD : 0); ref_transaction_add_update(transaction, refname, flags, - new_oid, old_oid, msg); + new_oid, old_oid, new_target, + old_target, msg); return 0; } @@ -1295,7 +1310,8 @@ int ref_transaction_create(struct ref_transaction *transaction, return 1; } return ref_transaction_update(transaction, refname, new_oid, - null_oid(), flags, msg, err); + null_oid(), NULL, NULL, flags, + msg, err); } int ref_transaction_delete(struct ref_transaction *transaction, @@ -1308,7 +1324,8 @@ int ref_transaction_delete(struct ref_transaction *transaction, BUG("delete called with old_oid set to zeros"); return ref_transaction_update(transaction, refname, null_oid(), old_oid, - flags, msg, err); + NULL, NULL, flags, + msg, err); } int ref_transaction_verify(struct ref_transaction *transaction, @@ -1321,6 +1338,7 @@ int ref_transaction_verify(struct ref_transaction *transaction, BUG("verify called with old_oid set to NULL"); return ref_transaction_update(transaction, refname, NULL, old_oid, + NULL, NULL, flags, NULL, err); } @@ -1335,8 +1353,8 @@ int refs_update_ref(struct ref_store *refs, const char *msg, t = ref_store_transaction_begin(refs, &err); if (!t || - ref_transaction_update(t, refname, new_oid, old_oid, flags, msg, - &err) || + ref_transaction_update(t, refname, new_oid, old_oid, NULL, NULL, + flags, msg, &err) || ref_transaction_commit(t, &err)) { ret = 1; ref_transaction_free(t); @@ -2266,25 +2284,33 @@ int peel_iterated_oid(const struct object_id *base, struct object_id *peeled) return peel_object(base, peeled) ? -1 : 0; } -int refs_create_symref(struct ref_store *refs, - const char *ref_target, - const char *refs_heads_master, - const char *logmsg) +int refs_update_symref(struct ref_store *refs, const char *ref, + const char *target, const char *logmsg) { - char *msg; - int retval; + struct ref_transaction *transaction; + struct strbuf err = STRBUF_INIT; + int ret = 0; - msg = normalize_reflog_message(logmsg); - retval = refs->be->create_symref(refs, ref_target, refs_heads_master, - msg); - free(msg); - return retval; + transaction = ref_store_transaction_begin(refs, &err); + if (!transaction || + ref_transaction_update(transaction, ref, NULL, NULL, + target, NULL, REF_NO_DEREF, + logmsg, &err) || + ref_transaction_commit(transaction, &err)) { + ret = error("%s", err.buf); + } + + strbuf_release(&err); + if (transaction) + ref_transaction_free(transaction); + + return ret; } int create_symref(const char *ref_target, const char *refs_heads_master, const char *logmsg) { - return refs_create_symref(get_main_ref_store(the_repository), ref_target, + return refs_update_symref(get_main_ref_store(the_repository), ref_target, refs_heads_master, logmsg); } @@ -2338,10 +2364,22 @@ static int run_transaction_hook(struct ref_transaction *transaction, struct ref_update *update = transaction->updates[i]; strbuf_reset(&buf); - strbuf_addf(&buf, "%s %s %s\n", - oid_to_hex(&update->old_oid), - oid_to_hex(&update->new_oid), - update->refname); + + if (!(update->flags & REF_HAVE_OLD)) + strbuf_addf(&buf, "%s ", oid_to_hex(null_oid())); + else if (update->old_target) + strbuf_addf(&buf, "ref:%s ", update->old_target); + else + strbuf_addf(&buf, "%s ", oid_to_hex(&update->old_oid)); + + if (!(update->flags & REF_HAVE_NEW)) + strbuf_addf(&buf, "%s ", oid_to_hex(null_oid())); + else if (update->new_target) + strbuf_addf(&buf, "ref:%s ", update->new_target); + else + strbuf_addf(&buf, "%s ", oid_to_hex(&update->new_oid)); + + strbuf_addf(&buf, "%s\n", update->refname); if (write_in_full(proc.in, buf.buf, buf.len) < 0) { if (errno != EPIPE) { @@ -2790,3 +2828,38 @@ int copy_existing_ref(const char *oldref, const char *newref, const char *logmsg { return refs_copy_existing_ref(get_main_ref_store(the_repository), oldref, newref, logmsg); } + +const char *ref_update_original_update_refname(struct ref_update *update) +{ + while (update->parent_update) + update = update->parent_update; + + return update->refname; +} + +int ref_update_has_null_new_value(struct ref_update *update) +{ + return !update->new_target && is_null_oid(&update->new_oid); +} + +int ref_update_check_old_target(const char *referent, struct ref_update *update, + struct strbuf *err) +{ + if (!update->old_target) + BUG("called without old_target set"); + + if (!strcmp(referent, update->old_target)) + return 0; + + if (!strcmp(referent, "")) + strbuf_addf(err, "verifying symref target: '%s': " + "reference is missing but expected %s", + ref_update_original_update_refname(update), + update->old_target); + else + strbuf_addf(err, "verifying symref target: '%s': " + "is at %s but expected %s", + ref_update_original_update_refname(update), + referent, update->old_target); + return -1; +} diff --git a/refs.h b/refs.h index d278775e08..71cc1c58e0 100644 --- a/refs.h +++ b/refs.h @@ -606,7 +606,7 @@ int refs_copy_existing_ref(struct ref_store *refs, const char *oldref, int copy_existing_ref(const char *oldref, const char *newref, const char *logmsg); -int refs_create_symref(struct ref_store *refs, const char *refname, +int refs_update_symref(struct ref_store *refs, const char *refname, const char *target, const char *logmsg); int create_symref(const char *refname, const char *target, const char *logmsg); @@ -648,6 +648,16 @@ struct ref_transaction *ref_transaction_begin(struct strbuf *err); * before the update. A copy of this value is made in the * transaction. * + * new_target -- the target reference that the reference will be + * updated to point to. If the reference is a regular reference, + * it will be converted to a symbolic reference. Cannot be set + * together with `new_oid`. A copy of this value is made in the + * transaction. + * + * old_target -- the reference that the reference must be pointing to. + * Canont be set together with `old_oid`. A copy of this value is + * made in the transaction. + * * flags -- flags affecting the update, passed to * update_ref_lock(). Possible flags: REF_NO_DEREF, * REF_FORCE_CREATE_REFLOG. See those constants for more @@ -713,7 +723,11 @@ struct ref_transaction *ref_transaction_begin(struct strbuf *err); * beforehand. The old value is checked after the lock is taken to * prevent races. If the old value doesn't agree with old_oid, the * whole transaction fails. If old_oid is NULL, then the previous - * value is not checked. + * value is not checked. If `old_target` is not NULL, treat the reference + * as a symbolic ref and validate that its target before the update is + * `old_target`. If the `new_target` is not NULL, then the reference + * will be updated to a symbolic ref which targets `new_target`. + * Together, these allow us to update between regular refs and symrefs. * * See the above comment "Reference transaction updates" for more * information. @@ -722,6 +736,8 @@ int ref_transaction_update(struct ref_transaction *transaction, const char *refname, const struct object_id *new_oid, const struct object_id *old_oid, + const char *new_target, + const char *old_target, unsigned int flags, const char *msg, struct strbuf *err); diff --git a/refs/debug.c b/refs/debug.c index c7531b17f0..8be316bb67 100644 --- a/refs/debug.c +++ b/refs/debug.c @@ -131,18 +131,6 @@ static int debug_pack_refs(struct ref_store *ref_store, struct pack_refs_opts *o return res; } -static int debug_create_symref(struct ref_store *ref_store, - const char *ref_name, const char *target, - const char *logmsg) -{ - struct debug_ref_store *drefs = (struct debug_ref_store *)ref_store; - int res = drefs->refs->be->create_symref(drefs->refs, ref_name, target, - logmsg); - trace_printf_key(&trace_refs, "create_symref: %s -> %s \"%s\": %d\n", ref_name, - target, logmsg, res); - return res; -} - static int debug_rename_ref(struct ref_store *ref_store, const char *oldref, const char *newref, const char *logmsg) { @@ -441,7 +429,6 @@ struct ref_storage_be refs_be_debug = { .initial_transaction_commit = debug_initial_transaction_commit, .pack_refs = debug_pack_refs, - .create_symref = debug_create_symref, .rename_ref = debug_rename_ref, .copy_ref = debug_copy_ref, diff --git a/refs/files-backend.c b/refs/files-backend.c index a098d14ea0..3957bfa579 100644 --- a/refs/files-backend.c +++ b/refs/files-backend.c @@ -1198,7 +1198,7 @@ static void prune_ref(struct files_ref_store *refs, struct ref_to_prune *r) ref_transaction_add_update( transaction, r->name, REF_NO_DEREF | REF_HAVE_NEW | REF_HAVE_OLD | REF_IS_PRUNING, - null_oid(), &r->oid, NULL); + null_oid(), &r->oid, NULL, NULL, NULL); if (ref_transaction_commit(transaction, &err)) goto cleanup; @@ -1292,7 +1292,7 @@ static int files_pack_refs(struct ref_store *ref_store, * packed-refs transaction: */ if (ref_transaction_update(transaction, iter->refname, - iter->oid, NULL, + iter->oid, NULL, NULL, NULL, REF_NO_DEREF, NULL, &err)) die("failure preparing to create packed reference %s: %s", iter->refname, err.buf); @@ -1903,66 +1903,23 @@ static int create_ref_symlink(struct ref_lock *lock, const char *target) return ret; } -static void update_symref_reflog(struct files_ref_store *refs, - struct ref_lock *lock, const char *refname, - const char *target, const char *logmsg) +static int create_symref_lock(struct files_ref_store *refs, + struct ref_lock *lock, const char *refname, + const char *target, struct strbuf *err) { - struct strbuf err = STRBUF_INIT; - struct object_id new_oid; - - if (logmsg && - refs_resolve_ref_unsafe(&refs->base, target, - RESOLVE_REF_READING, &new_oid, NULL) && - files_log_ref_write(refs, refname, &lock->old_oid, - &new_oid, logmsg, 0, &err)) { - error("%s", err.buf); - strbuf_release(&err); - } -} - -static int create_symref_locked(struct files_ref_store *refs, - struct ref_lock *lock, const char *refname, - const char *target, const char *logmsg) -{ - if (prefer_symlink_refs && !create_ref_symlink(lock, target)) { - update_symref_reflog(refs, lock, refname, target, logmsg); - return 0; - } - - if (!fdopen_lock_file(&lock->lk, "w")) - return error("unable to fdopen %s: %s", + if (!fdopen_lock_file(&lock->lk, "w")) { + strbuf_addf(err, "unable to fdopen %s: %s", get_lock_file_path(&lock->lk), strerror(errno)); - - update_symref_reflog(refs, lock, refname, target, logmsg); - - /* no error check; commit_ref will check ferror */ - fprintf(get_lock_file_fp(&lock->lk), "ref: %s\n", target); - if (commit_ref(lock) < 0) - return error("unable to write symref for %s: %s", refname, - strerror(errno)); - return 0; -} - -static int files_create_symref(struct ref_store *ref_store, - const char *refname, const char *target, - const char *logmsg) -{ - struct files_ref_store *refs = - files_downcast(ref_store, REF_STORE_WRITE, "create_symref"); - struct strbuf err = STRBUF_INIT; - struct ref_lock *lock; - int ret; - - lock = lock_ref_oid_basic(refs, refname, &err); - if (!lock) { - error("%s", err.buf); - strbuf_release(&err); return -1; } - ret = create_symref_locked(refs, lock, refname, target, logmsg); - unlock_ref(lock); - return ret; + if (fprintf(get_lock_file_fp(&lock->lk), "ref: %s\n", target) < 0) { + strbuf_addf(err, "unable to write to %s: %s", + get_lock_file_path(&lock->lk), strerror(errno)); + return -1; + } + + return 0; } static int files_reflog_exists(struct ref_store *ref_store, @@ -2309,7 +2266,7 @@ static int split_head_update(struct ref_update *update, transaction, "HEAD", update->flags | REF_LOG_ONLY | REF_NO_DEREF, &update->new_oid, &update->old_oid, - update->msg); + NULL, NULL, update->msg); /* * Add "HEAD". This insertion is O(N) in the transaction @@ -2371,8 +2328,9 @@ static int split_symref_update(struct ref_update *update, new_update = ref_transaction_add_update( transaction, referent, new_flags, - &update->new_oid, &update->old_oid, - update->msg); + update->new_target ? NULL : &update->new_oid, + update->old_target ? NULL : &update->old_oid, + update->new_target, update->old_target, update->msg); new_update->parent_update = update; @@ -2400,17 +2358,6 @@ static int split_symref_update(struct ref_update *update, return 0; } -/* - * Return the refname under which update was originally requested. - */ -static const char *original_update_refname(struct ref_update *update) -{ - while (update->parent_update) - update = update->parent_update; - - return update->refname; -} - /* * Check whether the REF_HAVE_OLD and old_oid values stored in update * are consistent with oid, which is the reference's current value. If @@ -2427,16 +2374,16 @@ static int check_old_oid(struct ref_update *update, struct object_id *oid, if (is_null_oid(&update->old_oid)) strbuf_addf(err, "cannot lock ref '%s': " "reference already exists", - original_update_refname(update)); + ref_update_original_update_refname(update)); else if (is_null_oid(oid)) strbuf_addf(err, "cannot lock ref '%s': " "reference is missing but expected %s", - original_update_refname(update), + ref_update_original_update_refname(update), oid_to_hex(&update->old_oid)); else strbuf_addf(err, "cannot lock ref '%s': " "is at %s but expected %s", - original_update_refname(update), + ref_update_original_update_refname(update), oid_to_hex(oid), oid_to_hex(&update->old_oid)); @@ -2471,7 +2418,7 @@ static int lock_ref_for_update(struct files_ref_store *refs, files_assert_main_repository(refs, "lock_ref_for_update"); - if ((update->flags & REF_HAVE_NEW) && is_null_oid(&update->new_oid)) + if ((update->flags & REF_HAVE_NEW) && ref_update_has_null_new_value(update)) update->flags |= REF_DELETING; if (head_ref) { @@ -2490,7 +2437,7 @@ static int lock_ref_for_update(struct files_ref_store *refs, reason = strbuf_detach(err, NULL); strbuf_addf(err, "cannot lock ref '%s': %s", - original_update_refname(update), reason); + ref_update_original_update_refname(update), reason); free(reason); goto out; } @@ -2510,11 +2457,18 @@ static int lock_ref_for_update(struct files_ref_store *refs, if (update->flags & REF_HAVE_OLD) { strbuf_addf(err, "cannot lock ref '%s': " "error reading reference", - original_update_refname(update)); + ref_update_original_update_refname(update)); ret = TRANSACTION_GENERIC_ERROR; goto out; } - } else if (check_old_oid(update, &lock->old_oid, err)) { + } + + if (update->old_target) { + if (ref_update_check_old_target(referent.buf, update, err)) { + ret = TRANSACTION_GENERIC_ERROR; + goto out; + } + } else if (check_old_oid(update, &lock->old_oid, err)) { ret = TRANSACTION_GENERIC_ERROR; goto out; } @@ -2535,7 +2489,17 @@ static int lock_ref_for_update(struct files_ref_store *refs, } else { struct ref_update *parent_update; - if (check_old_oid(update, &lock->old_oid, err)) { + /* + * Even if the ref is a regular ref, if `old_target` is set, we + * check the referent value. Ideally `old_target` should only + * be set for symrefs, but we're strict about its usage. + */ + if (update->old_target) { + if (ref_update_check_old_target(referent.buf, update, err)) { + ret = TRANSACTION_GENERIC_ERROR; + goto out; + } + } else if (check_old_oid(update, &lock->old_oid, err)) { ret = TRANSACTION_GENERIC_ERROR; goto out; } @@ -2553,9 +2517,28 @@ static int lock_ref_for_update(struct files_ref_store *refs, } } - if ((update->flags & REF_HAVE_NEW) && - !(update->flags & REF_DELETING) && - !(update->flags & REF_LOG_ONLY)) { + if (update->new_target && !(update->flags & REF_LOG_ONLY)) { + if (create_symref_lock(refs, lock, update->refname, + update->new_target, err)) { + ret = TRANSACTION_GENERIC_ERROR; + goto out; + } + + if (close_ref_gently(lock)) { + strbuf_addf(err, "couldn't close '%s.lock'", + update->refname); + ret = TRANSACTION_GENERIC_ERROR; + goto out; + } + + /* + * Once we have created the symref lock, the commit + * phase of the transaction only needs to commit the lock. + */ + update->flags |= REF_NEEDS_COMMIT; + } else if ((update->flags & REF_HAVE_NEW) && + !(update->flags & REF_DELETING) && + !(update->flags & REF_LOG_ONLY)) { if (!(update->type & REF_ISSYMREF) && oideq(&lock->old_oid, &update->new_oid)) { /* @@ -2763,7 +2746,7 @@ static int files_transaction_prepare(struct ref_store *ref_store, packed_transaction, update->refname, REF_HAVE_NEW | REF_NO_DEREF, &update->new_oid, NULL, - NULL); + NULL, NULL, NULL); } } @@ -2818,6 +2801,43 @@ static int files_transaction_prepare(struct ref_store *ref_store, return ret; } +static int parse_and_write_reflog(struct files_ref_store *refs, + struct ref_update *update, + struct ref_lock *lock, + struct strbuf *err) +{ + if (update->new_target) { + /* + * We want to get the resolved OID for the target, to ensure + * that the correct value is added to the reflog. + */ + if (!refs_resolve_ref_unsafe(&refs->base, update->new_target, + RESOLVE_REF_READING, + &update->new_oid, NULL)) { + /* + * TODO: currently we skip creating reflogs for dangling + * symref updates. It would be nice to capture this as + * zero oid updates however. + */ + return 0; + } + } + + if (files_log_ref_write(refs, lock->ref_name, &lock->old_oid, + &update->new_oid, update->msg, update->flags, err)) { + char *old_msg = strbuf_detach(err, NULL); + + strbuf_addf(err, "cannot update the ref '%s': %s", + lock->ref_name, old_msg); + free(old_msg); + unlock_ref(lock); + update->backend_data = NULL; + return -1; + } + + return 0; +} + static int files_transaction_finish(struct ref_store *ref_store, struct ref_transaction *transaction, struct strbuf *err) @@ -2848,23 +2868,20 @@ static int files_transaction_finish(struct ref_store *ref_store, if (update->flags & REF_NEEDS_COMMIT || update->flags & REF_LOG_ONLY) { - if (files_log_ref_write(refs, - lock->ref_name, - &lock->old_oid, - &update->new_oid, - update->msg, update->flags, - err)) { - char *old_msg = strbuf_detach(err, NULL); - - strbuf_addf(err, "cannot update the ref '%s': %s", - lock->ref_name, old_msg); - free(old_msg); - unlock_ref(lock); - update->backend_data = NULL; + if (parse_and_write_reflog(refs, update, lock, err)) { ret = TRANSACTION_GENERIC_ERROR; goto cleanup; } } + + /* + * We try creating a symlink, if that succeeds we continue to the + * next update. If not, we try and create a regular symref. + */ + if (update->new_target && prefer_symlink_refs) + if (!create_ref_symlink(lock, update->new_target)) + continue; + if (update->flags & REF_NEEDS_COMMIT) { clear_loose_ref_cache(refs); if (commit_ref(lock)) { @@ -3048,7 +3065,7 @@ static int files_initial_transaction_commit(struct ref_store *ref_store, ref_transaction_add_update(packed_transaction, update->refname, update->flags & ~REF_HAVE_OLD, &update->new_oid, &update->old_oid, - NULL); + NULL, NULL, NULL); } if (packed_refs_lock(refs->packed_ref_store, 0, err)) { @@ -3291,7 +3308,6 @@ struct ref_storage_be refs_be_files = { .initial_transaction_commit = files_initial_transaction_commit, .pack_refs = files_pack_refs, - .create_symref = files_create_symref, .rename_ref = files_rename_ref, .copy_ref = files_copy_ref, diff --git a/refs/packed-backend.c b/refs/packed-backend.c index 4e826c05ff..a937e7dbfc 100644 --- a/refs/packed-backend.c +++ b/refs/packed-backend.c @@ -1714,7 +1714,6 @@ struct ref_storage_be refs_be_packed = { .initial_transaction_commit = packed_initial_transaction_commit, .pack_refs = packed_pack_refs, - .create_symref = NULL, .rename_ref = NULL, .copy_ref = NULL, diff --git a/refs/refs-internal.h b/refs/refs-internal.h index 56641aa57a..53a6c5d842 100644 --- a/refs/refs-internal.h +++ b/refs/refs-internal.h @@ -124,6 +124,19 @@ struct ref_update { */ struct object_id old_oid; + /* + * If set, point the reference to this value. This can also be + * used to convert regular references to become symbolic refs. + * Cannot be set together with `new_oid`. + */ + const char *new_target; + + /* + * If set, check that the reference previously pointed to this + * value. Cannot be set together with `old_oid`. + */ + const char *old_target; + /* * One or more of REF_NO_DEREF, REF_FORCE_CREATE_REFLOG, * REF_HAVE_NEW, REF_HAVE_OLD, or backend-specific flags. @@ -173,6 +186,7 @@ struct ref_update *ref_transaction_add_update( const char *refname, unsigned int flags, const struct object_id *new_oid, const struct object_id *old_oid, + const char *new_target, const char *old_target, const char *msg); /* @@ -552,10 +566,6 @@ typedef int ref_transaction_commit_fn(struct ref_store *refs, typedef int pack_refs_fn(struct ref_store *ref_store, struct pack_refs_opts *opts); -typedef int create_symref_fn(struct ref_store *ref_store, - const char *ref_target, - const char *refs_heads_master, - const char *logmsg); typedef int rename_ref_fn(struct ref_store *ref_store, const char *oldref, const char *newref, const char *logmsg); @@ -676,7 +686,6 @@ struct ref_storage_be { ref_transaction_commit_fn *initial_transaction_commit; pack_refs_fn *pack_refs; - create_symref_fn *create_symref; rename_ref_fn *rename_ref; copy_ref_fn *copy_ref; @@ -735,4 +744,25 @@ void base_ref_store_init(struct ref_store *refs, struct repository *repo, */ struct ref_store *maybe_debug_wrap_ref_store(const char *gitdir, struct ref_store *store); +/* + * Return the refname under which update was originally requested. + */ +const char *ref_update_original_update_refname(struct ref_update *update); + +/* + * Helper function to check if the new value is null, this + * takes into consideration that the update could be a regular + * ref or a symbolic ref. + */ +int ref_update_has_null_new_value(struct ref_update *update); + +/* + * Check whether the old_target values stored in update are consistent + * with the referent, which is the symbolic reference's current value. + * If everything is OK, return 0; otherwise, write an error message to + * err and return -1. + */ +int ref_update_check_old_target(const char *referent, struct ref_update *update, + struct strbuf *err); + #endif /* REFS_REFS_INTERNAL_H */ diff --git a/refs/reftable-backend.c b/refs/reftable-backend.c index 1cda48c504..1b92c396b6 100644 --- a/refs/reftable-backend.c +++ b/refs/reftable-backend.c @@ -581,16 +581,6 @@ static int reftable_be_read_symbolic_ref(struct ref_store *ref_store, return ret; } -/* - * Return the refname under which update was originally requested. - */ -static const char *original_update_refname(struct ref_update *update) -{ - while (update->parent_update) - update = update->parent_update; - return update->refname; -} - struct reftable_transaction_update { struct ref_update *update; struct object_id current_oid; @@ -829,7 +819,7 @@ static int reftable_be_transaction_prepare(struct ref_store *ref_store, new_update = ref_transaction_add_update( transaction, "HEAD", u->flags | REF_LOG_ONLY | REF_NO_DEREF, - &u->new_oid, &u->old_oid, u->msg); + &u->new_oid, &u->old_oid, NULL, NULL, u->msg); string_list_insert(&affected_refnames, new_update->refname); } @@ -856,7 +846,7 @@ static int reftable_be_transaction_prepare(struct ref_store *ref_store, * There is no need to write the reference deletion * when the reference in question doesn't exist. */ - if (u->flags & REF_HAVE_NEW && !is_null_oid(&u->new_oid)) { + if ((u->flags & REF_HAVE_NEW) && !ref_update_has_null_new_value(u)) { ret = queue_transaction_update(refs, tx_data, u, ¤t_oid, err); if (ret) @@ -869,7 +859,7 @@ static int reftable_be_transaction_prepare(struct ref_store *ref_store, /* The reference does not exist, but we expected it to. */ strbuf_addf(err, _("cannot lock ref '%s': " "unable to resolve reference '%s'"), - original_update_refname(u), u->refname); + ref_update_original_update_refname(u), u->refname); ret = -1; goto done; } @@ -907,8 +897,10 @@ static int reftable_be_transaction_prepare(struct ref_store *ref_store, * intertwined with the locking in files-backend.c. */ new_update = ref_transaction_add_update( - transaction, referent.buf, new_flags, - &u->new_oid, &u->old_oid, u->msg); + transaction, referent.buf, new_flags, + &u->new_oid, &u->old_oid, u->new_target, + u->old_target, u->msg); + new_update->parent_update = u; /* @@ -938,20 +930,25 @@ static int reftable_be_transaction_prepare(struct ref_store *ref_store, * individual refs. But the error messages match what the files * backend returns, which keeps our tests happy. */ - if (u->flags & REF_HAVE_OLD && !oideq(¤t_oid, &u->old_oid)) { + if (u->old_target) { + if (ref_update_check_old_target(referent.buf, u, err)) { + ret = -1; + goto done; + } + } else if ((u->flags & REF_HAVE_OLD) && !oideq(¤t_oid, &u->old_oid)) { if (is_null_oid(&u->old_oid)) strbuf_addf(err, _("cannot lock ref '%s': " - "reference already exists"), - original_update_refname(u)); + "reference already exists"), + ref_update_original_update_refname(u)); else if (is_null_oid(¤t_oid)) strbuf_addf(err, _("cannot lock ref '%s': " - "reference is missing but expected %s"), - original_update_refname(u), + "reference is missing but expected %s"), + ref_update_original_update_refname(u), oid_to_hex(&u->old_oid)); else strbuf_addf(err, _("cannot lock ref '%s': " - "is at %s but expected %s"), - original_update_refname(u), + "is at %s but expected %s"), + ref_update_original_update_refname(u), oid_to_hex(¤t_oid), oid_to_hex(&u->old_oid)); ret = -1; @@ -1043,7 +1040,9 @@ static int write_transaction_table(struct reftable_writer *writer, void *cb_data * - `core.logAllRefUpdates` tells us to create the reflog for * the given ref. */ - if (u->flags & REF_HAVE_NEW && !(u->type & REF_ISSYMREF) && is_null_oid(&u->new_oid)) { + if ((u->flags & REF_HAVE_NEW) && + !(u->type & REF_ISSYMREF) && + ref_update_has_null_new_value(u)) { struct reftable_log_record log = {0}; struct reftable_iterator it = {0}; @@ -1084,24 +1083,52 @@ static int write_transaction_table(struct reftable_writer *writer, void *cb_data (u->flags & REF_FORCE_CREATE_REFLOG || should_write_log(&arg->refs->base, u->refname))) { struct reftable_log_record *log; + int create_reflog = 1; - ALLOC_GROW(logs, logs_nr + 1, logs_alloc); - log = &logs[logs_nr++]; - memset(log, 0, sizeof(*log)); + if (u->new_target) { + if (!refs_resolve_ref_unsafe(&arg->refs->base, u->new_target, + RESOLVE_REF_READING, &u->new_oid, NULL)) { + /* + * TODO: currently we skip creating reflogs for dangling + * symref updates. It would be nice to capture this as + * zero oid updates however. + */ + create_reflog = 0; + } + } - fill_reftable_log_record(log); - log->update_index = ts; - log->refname = xstrdup(u->refname); - memcpy(log->value.update.new_hash, u->new_oid.hash, GIT_MAX_RAWSZ); - memcpy(log->value.update.old_hash, tx_update->current_oid.hash, GIT_MAX_RAWSZ); - log->value.update.message = - xstrndup(u->msg, arg->refs->write_options.block_size / 2); + if (create_reflog) { + ALLOC_GROW(logs, logs_nr + 1, logs_alloc); + log = &logs[logs_nr++]; + memset(log, 0, sizeof(*log)); + + fill_reftable_log_record(log); + log->update_index = ts; + log->refname = xstrdup(u->refname); + memcpy(log->value.update.new_hash, + u->new_oid.hash, GIT_MAX_RAWSZ); + memcpy(log->value.update.old_hash, + tx_update->current_oid.hash, GIT_MAX_RAWSZ); + log->value.update.message = + xstrndup(u->msg, arg->refs->write_options.block_size / 2); + } } if (u->flags & REF_LOG_ONLY) continue; - if (u->flags & REF_HAVE_NEW && is_null_oid(&u->new_oid)) { + if (u->new_target) { + struct reftable_ref_record ref = { + .refname = (char *)u->refname, + .value_type = REFTABLE_REF_SYMREF, + .value.symref = (char *)u->new_target, + .update_index = ts, + }; + + ret = reftable_writer_add_ref(writer, &ref); + if (ret < 0) + goto done; + } else if ((u->flags & REF_HAVE_NEW) && ref_update_has_null_new_value(u)) { struct reftable_ref_record ref = { .refname = (char *)u->refname, .update_index = ts, @@ -1232,91 +1259,6 @@ struct write_create_symref_arg { const char *logmsg; }; -static int write_create_symref_table(struct reftable_writer *writer, void *cb_data) -{ - struct write_create_symref_arg *create = cb_data; - uint64_t ts = reftable_stack_next_update_index(create->stack); - struct reftable_ref_record ref = { - .refname = (char *)create->refname, - .value_type = REFTABLE_REF_SYMREF, - .value.symref = (char *)create->target, - .update_index = ts, - }; - struct reftable_log_record log = {0}; - struct object_id new_oid; - struct object_id old_oid; - int ret; - - reftable_writer_set_limits(writer, ts, ts); - - ret = reftable_writer_add_ref(writer, &ref); - if (ret) - return ret; - - /* - * Note that it is important to try and resolve the reference before we - * write the log entry. This is because `should_write_log()` will munge - * `core.logAllRefUpdates`, which is undesirable when we create a new - * repository because it would be written into the config. As HEAD will - * not resolve for new repositories this ordering will ensure that this - * never happens. - */ - if (!create->logmsg || - !refs_resolve_ref_unsafe(&create->refs->base, create->target, - RESOLVE_REF_READING, &new_oid, NULL) || - !should_write_log(&create->refs->base, create->refname)) - return 0; - - fill_reftable_log_record(&log); - log.refname = xstrdup(create->refname); - log.update_index = ts; - log.value.update.message = xstrndup(create->logmsg, - create->refs->write_options.block_size / 2); - memcpy(log.value.update.new_hash, new_oid.hash, GIT_MAX_RAWSZ); - if (refs_resolve_ref_unsafe(&create->refs->base, create->refname, - RESOLVE_REF_READING, &old_oid, NULL)) - memcpy(log.value.update.old_hash, old_oid.hash, GIT_MAX_RAWSZ); - - ret = reftable_writer_add_log(writer, &log); - reftable_log_record_release(&log); - return ret; -} - -static int reftable_be_create_symref(struct ref_store *ref_store, - const char *refname, - const char *target, - const char *logmsg) -{ - struct reftable_ref_store *refs = - reftable_be_downcast(ref_store, REF_STORE_WRITE, "create_symref"); - struct reftable_stack *stack = stack_for(refs, refname, &refname); - struct write_create_symref_arg arg = { - .refs = refs, - .stack = stack, - .refname = refname, - .target = target, - .logmsg = logmsg, - }; - int ret; - - ret = refs->err; - if (ret < 0) - goto done; - - ret = reftable_stack_reload(stack); - if (ret) - goto done; - - ret = reftable_stack_add(stack, &write_create_symref_table, &arg); - -done: - assert(ret != REFTABLE_API_ERROR); - if (ret) - error("unable to write symref for %s: %s", refname, - reftable_error_str(ret)); - return ret; -} - struct write_copy_arg { struct reftable_ref_store *refs; struct reftable_stack *stack; @@ -2224,7 +2166,6 @@ struct ref_storage_be refs_be_reftable = { .initial_transaction_commit = reftable_be_initial_transaction_commit, .pack_refs = reftable_be_pack_refs, - .create_symref = reftable_be_create_symref, .rename_ref = reftable_be_rename_ref, .copy_ref = reftable_be_copy_ref, diff --git a/sequencer.c b/sequencer.c index 2c19846385..af1b25692b 100644 --- a/sequencer.c +++ b/sequencer.c @@ -616,7 +616,7 @@ static int fast_forward_to(struct repository *r, if (!transaction || ref_transaction_update(transaction, "HEAD", to, unborn && !is_rebase_i(opts) ? - null_oid() : from, + null_oid() : from, NULL, NULL, 0, sb.buf, &err) || ref_transaction_commit(transaction, &err)) { ref_transaction_free(transaction); @@ -1248,7 +1248,7 @@ int update_head_with_reflog(const struct commit *old_head, if (!transaction || ref_transaction_update(transaction, "HEAD", new_head, old_head ? &old_head->object.oid : null_oid(), - 0, sb.buf, err) || + NULL, NULL, 0, sb.buf, err) || ref_transaction_commit(transaction, err)) { ret = -1; } @@ -3764,8 +3764,9 @@ static int do_label(struct repository *r, const char *name, int len) } else if (repo_get_oid(r, "HEAD", &head_oid)) { error(_("could not read HEAD")); ret = -1; - } else if (ref_transaction_update(transaction, ref_name.buf, &head_oid, - NULL, 0, msg.buf, &err) < 0 || + } else if (ref_transaction_update(transaction, ref_name.buf, + &head_oid, NULL, NULL, NULL, + 0, msg.buf, &err) < 0 || ref_transaction_commit(transaction, &err)) { error("%s", err.buf); ret = -1; diff --git a/t/helper/test-ref-store.c b/t/helper/test-ref-store.c index 82bbf6e2e6..4651e4ced7 100644 --- a/t/helper/test-ref-store.c +++ b/t/helper/test-ref-store.c @@ -118,7 +118,7 @@ static int cmd_create_symref(struct ref_store *refs, const char **argv) const char *target = notnull(*argv++, "target"); const char *logmsg = *argv++; - return refs_create_symref(refs, refname, target, logmsg); + return refs_update_symref(refs, refname, target, logmsg); } static struct flag_definition transaction_flags[] = { diff --git a/t/t0610-reftable-basics.sh b/t/t0610-reftable-basics.sh index 178791e086..9e8d22bcbd 100755 --- a/t/t0610-reftable-basics.sh +++ b/t/t0610-reftable-basics.sh @@ -286,7 +286,7 @@ test_expect_success 'ref transaction: creating symbolic ref fails with F/D confl git init repo && test_commit -C repo A && cat >expect <<-EOF && - error: unable to write symref for refs/heads: file/directory conflict + error: ${SQ}refs/heads/main${SQ} exists; cannot create ${SQ}refs/heads${SQ} EOF test_must_fail git -C repo symbolic-ref refs/heads refs/heads/foo 2>err && test_cmp expect err diff --git a/t/t1416-ref-transaction-hooks.sh b/t/t1416-ref-transaction-hooks.sh index 2092488090..067fd57290 100755 --- a/t/t1416-ref-transaction-hooks.sh +++ b/t/t1416-ref-transaction-hooks.sh @@ -134,4 +134,27 @@ test_expect_success 'interleaving hook calls succeed' ' test_cmp expect target-repo.git/actual ' +test_expect_success 'hook captures git-symbolic-ref updates' ' + test_when_finished "rm actual" && + + test_hook reference-transaction <<-\EOF && + echo "$*" >>actual + while read -r line + do + printf "%s\n" "$line" + done >>actual + EOF + + git symbolic-ref refs/heads/symref refs/heads/main && + + cat >expect <<-EOF && + prepared + $ZERO_OID ref:refs/heads/main refs/heads/symref + committed + $ZERO_OID ref:refs/heads/main refs/heads/symref + EOF + + test_cmp expect actual +' + test_done diff --git a/walker.c b/walker.c index c0fd632d92..1b3df43906 100644 --- a/walker.c +++ b/walker.c @@ -324,7 +324,7 @@ int walker_fetch(struct walker *walker, int targets, char **target, strbuf_reset(&refname); strbuf_addf(&refname, "refs/%s", write_ref[i]); if (ref_transaction_update(transaction, refname.buf, - oids + i, NULL, 0, + oids + i, NULL, NULL, NULL, 0, msg ? msg : "fetch (unknown)", &err)) { error("%s", err.buf);