From mboxrd@z Thu Jan 1 00:00:00 1970 From: David Turner Subject: [PATCH v4 14/21] refs: always handle non-normal refs in files backend Date: Fri, 5 Feb 2016 14:44:15 -0500 Message-ID: <1454701462-3817-15-git-send-email-dturner@twopensource.com> References: <1454701462-3817-1-git-send-email-dturner@twopensource.com> Cc: David Turner To: git@vger.kernel.org, mhagger@alum.mit.edu X-From: git-owner@vger.kernel.org Fri Feb 05 20:45:20 2016 Return-path: Envelope-to: gcvg-git-2@plane.gmane.org Received: from vger.kernel.org ([209.132.180.67]) by plane.gmane.org with esmtp (Exim 4.69) (envelope-from ) id 1aRmJj-0001Xn-Ml for gcvg-git-2@plane.gmane.org; Fri, 05 Feb 2016 20:45:20 +0100 Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755386AbcBETpM (ORCPT ); Fri, 5 Feb 2016 14:45:12 -0500 Received: from mail-qg0-f53.google.com ([209.85.192.53]:36046 "EHLO mail-qg0-f53.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755178AbcBETpA (ORCPT ); Fri, 5 Feb 2016 14:45:00 -0500 Received: by mail-qg0-f53.google.com with SMTP id y9so71847433qgd.3 for ; Fri, 05 Feb 2016 11:44:59 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=twopensource-com.20150623.gappssmtp.com; s=20150623; h=from:to:cc:subject:date:message-id:in-reply-to:references; bh=RwSDOws+L4jIOd+yNMGDPafCEFran/RN98GWIba1dSQ=; b=sziId2F+Q1FYVygeQGO2kQKnLwJkeL00Pu5CbS4YYbrwrwF18fSr3ILXKMOPdUJ8EN Szk+1BnitqEkIPJiiaV+toL4U6EwWHO41FVBMvj76bfHaG+oXcqD0eo+9NIqfscnrbpf C4fhYoHVms63ifthBWMzfG/IjyZL8PTSXS8gkHJv1n/abrBVci54hygpfy6/3+rwtVDm qQlCYh/slvMbpcoLq60GJD3li0Xoze2silUGXXt58n3538mO5bx946YSrcWgpYq0AbYd zvUb6V9TpqBC96OnQTSFa4nIySB9kUmpS0G0KhrQSP6Ws9nN5dQkbhNVKQ2UArROPeRS a05g== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20130820; h=x-gm-message-state:from:to:cc:subject:date:message-id:in-reply-to :references; bh=RwSDOws+L4jIOd+yNMGDPafCEFran/RN98GWIba1dSQ=; b=A0mTyYJBsHHgO6038pJDHP52nTyuKuxzMYBEIVvlqnduQV0vbeBMNjbLuzW72A5jJR Upqz9IcCSBamWV9EnqlH7eeulpLVFAZ/fUffOkoBr5fwdbqopAnuXJf2o+h2sJby5AXz mHl2pmhCIL3696KE6iMPChEe4EPElR53H18aAnX/kcQKsP6DtVW2N3XHRg8SxXnwnz6v xwGiODixpD0j33jD71qw+KNvW0lq615xZzJ+bGdTuCkv3yNCjKRpgf/GdfhkB2dYnzYb AaFUsmAzUJ8HeIS4ax53YRHUrqigYw0yQ6WxLPuNVlkXCvPBxDttIA/Mzdt3KFWInnyb Y+bw== X-Gm-Message-State: AG10YOQUluHoiWRZHxgsSR59m9f5fjbgZqfscTLajT0i+tFys2NYsPMJGo3R1w2q2kRvCw== X-Received: by 10.140.236.68 with SMTP id h65mr19906943qhc.13.1454701499122; Fri, 05 Feb 2016 11:44:59 -0800 (PST) Received: from ubuntu.twitter.biz ([192.133.79.145]) by smtp.gmail.com with ESMTPSA id g109sm8565535qgg.40.2016.02.05.11.44.57 (version=TLSv1/SSLv3 cipher=OTHER); Fri, 05 Feb 2016 11:44:58 -0800 (PST) X-Mailer: git-send-email 2.4.2.749.g730654d-twtrsrc In-Reply-To: <1454701462-3817-1-git-send-email-dturner@twopensource.com> Sender: git-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: git@vger.kernel.org Archived-At: Always handle non-normal (per-worktree or pseudo) refs in the files backend instead of alternate backends. Sometimes a ref transaction will update both a per-worktree ref and a normal ref. For instance, an ordinary commit might update refs/heads/master and HEAD (or at least HEAD's reflog). Updates to normal refs continue to go through the chosen backend. Updates to non-normal refs are moved to a separate files backend transaction. Signed-off-by: David Turner --- refs.c | 81 ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++-- 1 file changed, 79 insertions(+), 2 deletions(-) diff --git a/refs.c b/refs.c index 227c018..18ba356 100644 --- a/refs.c +++ b/refs.c @@ -9,6 +9,11 @@ #include "object.h" #include "tag.h" +static const char split_transaction_fail_warning[] = N_( + "A ref transaction was split across two refs backends. Part of the " + "transaction succeeded, but then the update to the per-worktree refs " + "failed. Your repository may be in an inconsistent state."); + /* * We always have a files backend and it is the default. */ @@ -791,6 +796,13 @@ void ref_transaction_free(struct ref_transaction *transaction) free(transaction); } +static void add_update_obj(struct ref_transaction *transaction, + struct ref_update *update) +{ + ALLOC_GROW(transaction->updates, transaction->nr + 1, transaction->alloc); + transaction->updates[transaction->nr++] = update; +} + static struct ref_update *add_update(struct ref_transaction *transaction, const char *refname) { @@ -798,8 +810,7 @@ static struct ref_update *add_update(struct ref_transaction *transaction, struct ref_update *update = xcalloc(1, sizeof(*update) + len); memcpy((char *)update->refname, refname, len); /* includes NUL */ - ALLOC_GROW(transaction->updates, transaction->nr + 1, transaction->alloc); - transaction->updates[transaction->nr++] = update; + add_update_obj(transaction, update); return update; } @@ -1217,11 +1228,38 @@ static int dereference_symrefs(struct ref_transaction *transaction, return 0; } +/* + * Move all non-normal ref updates into a specially-created + * files-backend transaction + */ +static int move_abnormal_ref_updates(struct ref_transaction *transaction, + struct ref_transaction *files_transaction, + struct strbuf *err) +{ + int i; + + for (i = 0; i < transaction->nr; i++) { + int last; + struct ref_update *update = transaction->updates[i]; + + if (ref_type(update->refname) == REF_TYPE_NORMAL) + continue; + + last = --transaction->nr; + transaction->updates[i] = transaction->updates[last]; + add_update_obj(files_transaction, update); + } + + return 0; +} + int ref_transaction_commit(struct ref_transaction *transaction, struct strbuf *err) { int ret = -1; struct string_list affected_refnames = STRING_LIST_INIT_NODUP; + struct string_list files_affected_refnames = STRING_LIST_INIT_NODUP; + struct ref_transaction *files_transaction = NULL; assert(err); @@ -1237,6 +1275,26 @@ int ref_transaction_commit(struct ref_transaction *transaction, if (ret) goto done; + if (the_refs_backend != &refs_be_files) { + files_transaction = ref_transaction_begin(err); + if (!files_transaction) + goto done; + + ret = move_abnormal_ref_updates(transaction, files_transaction, + err); + if (ret) + goto done; + + /* files backend commit */ + if (get_affected_refnames(files_transaction, + &files_affected_refnames, + err)) { + ret = TRANSACTION_GENERIC_ERROR; + goto done; + } + } + + /* main backend commit */ if (get_affected_refnames(transaction, &affected_refnames, err)) { ret = TRANSACTION_GENERIC_ERROR; goto done; @@ -1244,8 +1302,24 @@ int ref_transaction_commit(struct ref_transaction *transaction, ret = the_refs_backend->transaction_commit(transaction, &affected_refnames, err); + if (ret) + goto done; + + if (files_transaction) { + ret = refs_be_files.transaction_commit(files_transaction, + &files_affected_refnames, + err); + if (ret) { + warning(split_transaction_fail_warning); + goto done; + } + } + done: string_list_clear(&affected_refnames, 0); + string_list_clear(&files_affected_refnames, 0); + if (files_transaction) + ref_transaction_free(files_transaction); return ret; } @@ -1285,6 +1359,9 @@ int peel_ref(const char *refname, unsigned char *sha1) int create_symref(const char *ref_target, const char *refs_heads_master, const char *logmsg) { + if (ref_type(ref_target) != REF_TYPE_NORMAL) + return refs_be_files.create_symref(ref_target, refs_heads_master, + logmsg); return the_refs_backend->create_symref(ref_target, refs_heads_master, logmsg); } -- 2.4.2.749.g730654d-twtrsrc