From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.2 (2018-09-13) on dcvr.yhbt.net X-Spam-Level: X-Spam-ASN: AS53758 23.128.96.0/24 X-Spam-Status: No, score=-3.7 required=3.0 tests=AWL,BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_PASS, SPF_PASS shortcircuit=no autolearn=ham autolearn_force=no version=3.4.2 Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by dcvr.yhbt.net (Postfix) with ESMTP id 38A9C1F9F3 for ; Fri, 23 Apr 2021 15:31:56 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S242861AbhDWPca (ORCPT ); Fri, 23 Apr 2021 11:32:30 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:56386 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230294AbhDWPc2 (ORCPT ); Fri, 23 Apr 2021 11:32:28 -0400 Received: from mail-wr1-x436.google.com (mail-wr1-x436.google.com [IPv6:2a00:1450:4864:20::436]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 93E62C06174A for ; Fri, 23 Apr 2021 08:31:51 -0700 (PDT) Received: by mail-wr1-x436.google.com with SMTP id r7so36806655wrm.1 for ; Fri, 23 Apr 2021 08:31:51 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=message-id:in-reply-to:references:from:date:subject:fcc :content-transfer-encoding:mime-version:to:cc; bh=F4HOaeHIO7KS1k6ttHWwH5r5xh4Z26cSAfantBfReEo=; b=YfbfU0I5I+ZnQf8s3+gSHKplQPL2SbRZOmLn6cP9zH6hbfPPMlCSOrLwuobLr5qcGt pG3cVo2qAFMqpaLibkvB/ek4fvIUSQvRvmdt/dzAe3Ysw7hZwTd8ayoZ1kQiW5r+1lDR fIkA2PDbUMe107I4z+UjBiaYLCuxHmyUuC2WJ2GFjXqfH9q+kLuEmGcPPBLFZ9P7hiMT TaYVIvlpu6iUAEISqawiec++Kl4gdqHPiNjgEyzpxNkWe9bHpccBczAWcIPPBVtRPL98 clOqixD9O0avznAFdnXahh8Lm47MCRsAisMaVQZCaKCTHxB0zyut4b2LH/z1llVgFDLs p4Sw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:message-id:in-reply-to:references:from:date :subject:fcc:content-transfer-encoding:mime-version:to:cc; bh=F4HOaeHIO7KS1k6ttHWwH5r5xh4Z26cSAfantBfReEo=; b=RvGB2TUPzYOVazmNqAcGLro7LGOjdr2BPCD5PFPUqTTv8GFAwl+1O11eDoTHyM0i1B IkON+UJsGhFZLGImZCPTm/pA9q3wUtqXk1jMIxGHc2OhduhwZOyJtxqjiqGY224WQdCG KG9kRXFJ0cz9vSZ6N0ewzPwlIGtK7r5KXMuNEgeFmkSlSCDng3NUWZg2JBm92O8KQrDc fl0p5YNrltwYjWBIYDMud13mZxB0+P1d9LvmFdJ4EHKKeJQzQHXb8+SILRzscWBf8+H5 YHRy2xzdXgjKcDNudg/s/9JsXsGpT6VMQ1wixrlKxlV6Pk+uXXdwSrh1MvRGh2I3/9PD kszA== X-Gm-Message-State: AOAM530fhy0FNG0TA71CBgXOTn1+ekemTvNVMp/JbVBO+JKbLpE4esj9 GG4MlYd7WKfGxl9NcjOtcsG3x792vtc= X-Google-Smtp-Source: ABdhPJwxce8cL5JjCaHAmhYCxyw2xj0txGmMU21ccodkDh1FcQ4aAbTksB4QqKjj8/Bn73DkfL+mTg== X-Received: by 2002:a5d:6d0a:: with SMTP id e10mr5561648wrq.161.1619191910397; Fri, 23 Apr 2021 08:31:50 -0700 (PDT) Received: from [127.0.0.1] ([13.74.141.28]) by smtp.gmail.com with ESMTPSA id u4sm12608293wml.0.2021.04.23.08.31.50 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Fri, 23 Apr 2021 08:31:50 -0700 (PDT) Message-Id: <7fbc1c754f435c6d621734685ebee1bdc539c000.1619191907.git.gitgitgadget@gmail.com> In-Reply-To: References: From: "Han-Wen Nienhuys via GitGitGadget" Date: Fri, 23 Apr 2021 15:31:47 +0000 Subject: [PATCH v2 3/3] refs: make errno output explicit for read_raw_ref_fn Fcc: Sent Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit MIME-Version: 1.0 To: git@vger.kernel.org Cc: Han-Wen Nienhuys , Han-Wen Nienhuys , Han-Wen Nienhuys Precedence: bulk List-ID: X-Mailing-List: git@vger.kernel.org From: Han-Wen Nienhuys read_raw_ref_fn needs to supply a credible errno for a number of cases. These are primarily: 1) The files backend calls read_raw_ref from lock_raw_ref, and uses the resulting error codes to create/remove directories as needed. 2) ENOENT should be translated in a zero OID, optionally with REF_ISBROKEN set, returning the last successfully resolved symref. This is necessary so read_raw_ref("HEAD") on an empty repo returns refs/heads/main (or the default branch du-jour), and we know on which branch to create the first commit. Make this information flow explicit by adding a failure_errno to the signature of read_raw_ref. All errnos from the files backend are still propagated unchanged, even though inspection suggests only ENOTDIR, EISDIR and ENOENT are relevant. Signed-off-by: Han-Wen Nienhuys --- refs.c | 7 +++++-- refs/debug.c | 4 ++-- refs/files-backend.c | 17 ++++++++--------- refs/packed-backend.c | 5 +++-- refs/refs-internal.h | 9 ++++++--- 5 files changed, 24 insertions(+), 18 deletions(-) diff --git a/refs.c b/refs.c index 261fd82beb98..43e2ad6b612a 100644 --- a/refs.c +++ b/refs.c @@ -1675,13 +1675,16 @@ int refs_read_raw_ref(struct ref_store *ref_store, const char *refname, struct object_id *oid, struct strbuf *referent, unsigned int *type) { + int result, failure; if (!strcmp(refname, "FETCH_HEAD") || !strcmp(refname, "MERGE_HEAD")) { return refs_read_special_head(ref_store, refname, oid, referent, type); } - return ref_store->be->read_raw_ref(ref_store, refname, oid, referent, - type); + result = ref_store->be->read_raw_ref(ref_store, refname, oid, referent, + type, &failure); + errno = failure; + return result; } /* This function needs to return a meaningful errno on failure */ diff --git a/refs/debug.c b/refs/debug.c index 922e64fa6ad9..887dbb14be6e 100644 --- a/refs/debug.c +++ b/refs/debug.c @@ -238,14 +238,14 @@ debug_ref_iterator_begin(struct ref_store *ref_store, const char *prefix, static int debug_read_raw_ref(struct ref_store *ref_store, const char *refname, struct object_id *oid, struct strbuf *referent, - unsigned int *type) + unsigned int *type, int *failure_errno) { struct debug_ref_store *drefs = (struct debug_ref_store *)ref_store; int res = 0; oidcpy(oid, &null_oid); res = drefs->refs->be->read_raw_ref(drefs->refs, refname, oid, referent, - type); + type, failure_errno); if (res == 0) { trace_printf_key(&trace_refs, "read_raw_ref: %s: %s (=> %s) type %x: %d\n", diff --git a/refs/files-backend.c b/refs/files-backend.c index c9511da1d387..3ba3a96e1c6b 100644 --- a/refs/files-backend.c +++ b/refs/files-backend.c @@ -343,7 +343,7 @@ static struct ref_cache *get_loose_ref_cache(struct files_ref_store *refs) static int files_read_raw_ref(struct ref_store *ref_store, const char *refname, struct object_id *oid, - struct strbuf *referent, unsigned int *type) + struct strbuf *referent, unsigned int *type, int *failure_errno) { struct files_ref_store *refs = files_downcast(ref_store, REF_STORE_READ, "read_raw_ref"); @@ -354,7 +354,6 @@ static int files_read_raw_ref(struct ref_store *ref_store, struct stat st; int fd; int ret = -1; - int save_errno; int remaining_retries = 3; *type = 0; @@ -459,10 +458,9 @@ static int files_read_raw_ref(struct ref_store *ref_store, ret = parse_loose_ref_contents(buf, oid, referent, type); out: - save_errno = errno; + *failure_errno = errno; strbuf_release(&sb_path); strbuf_release(&sb_contents); - errno = save_errno; return ret; } @@ -541,6 +539,7 @@ static int lock_raw_ref(struct files_ref_store *refs, struct strbuf ref_file = STRBUF_INIT; int attempts_remaining = 3; int ret = TRANSACTION_GENERIC_ERROR; + int failure_errno = 0; assert(err); files_assert_main_repository(refs, "lock_raw_ref"); @@ -630,8 +629,8 @@ static int lock_raw_ref(struct files_ref_store *refs, */ if (files_read_raw_ref(&refs->base, refname, - &lock->old_oid, referent, type)) { - if (errno == ENOENT) { + &lock->old_oid, referent, type, &failure_errno)) { + if (failure_errno == ENOENT) { if (mustexist) { /* Garden variety missing reference. */ strbuf_addf(err, "unable to resolve reference '%s'", @@ -655,7 +654,7 @@ static int lock_raw_ref(struct files_ref_store *refs, * reference named "refs/foo/bar/baz". */ } - } else if (errno == EISDIR) { + } else if (failure_errno == EISDIR) { /* * There is a directory in the way. It might have * contained references that have been deleted. If @@ -693,13 +692,13 @@ static int lock_raw_ref(struct files_ref_store *refs, goto error_return; } } - } else if (errno == EINVAL && (*type & REF_ISBROKEN)) { + } else if (failure_errno == EINVAL && (*type & REF_ISBROKEN)) { strbuf_addf(err, "unable to resolve reference '%s': " "reference broken", refname); goto error_return; } else { strbuf_addf(err, "unable to resolve reference '%s': %s", - refname, strerror(errno)); + refname, strerror(failure_errno)); goto error_return; } diff --git a/refs/packed-backend.c b/refs/packed-backend.c index dfecdbc1db60..9a09ad7f5f29 100644 --- a/refs/packed-backend.c +++ b/refs/packed-backend.c @@ -726,7 +726,8 @@ static struct snapshot *get_snapshot(struct packed_ref_store *refs) static int packed_read_raw_ref(struct ref_store *ref_store, const char *refname, struct object_id *oid, - struct strbuf *referent, unsigned int *type) + struct strbuf *referent, unsigned int *type, + int *failure_errno) { struct packed_ref_store *refs = packed_downcast(ref_store, REF_STORE_READ, "read_raw_ref"); @@ -739,7 +740,7 @@ static int packed_read_raw_ref(struct ref_store *ref_store, if (!rec) { /* refname is not a packed reference. */ - errno = ENOENT; + *failure_errno = ENOENT; return -1; } diff --git a/refs/refs-internal.h b/refs/refs-internal.h index 29728a339fed..15cc0ddd68ab 100644 --- a/refs/refs-internal.h +++ b/refs/refs-internal.h @@ -617,9 +617,11 @@ typedef int reflog_expire_fn(struct ref_store *ref_store, * properly-formatted or even safe reference name. NEITHER INPUT NOR * OUTPUT REFERENCE NAMES ARE VALIDATED WITHIN THIS FUNCTION. * - * Return 0 on success. If the ref doesn't exist, set errno to ENOENT and return + * Return 0 on success. If the ref doesn't exist, set failure_errno to ENOENT and return * -1. If the ref exists but is neither a symbolic ref nor an object ID, it is - * broken; set REF_ISBROKEN in type, and return -1. If there is another error + * broken; set REF_ISBROKEN in type, and return -1. For the files backend, EISDIR and ENOTDIR + * may be set if the ref name is a directory + * If there is another error * reading the ref, set errno appropriately and return -1. * * Backend-specific flags might be set in type as well, regardless of @@ -636,7 +638,8 @@ typedef int reflog_expire_fn(struct ref_store *ref_store, */ typedef int read_raw_ref_fn(struct ref_store *ref_store, const char *refname, struct object_id *oid, - struct strbuf *referent, unsigned int *type); + struct strbuf *referent, unsigned int *type, + int *failure_errno); struct ref_storage_be { struct ref_storage_be *next; -- gitgitgadget