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-Status: No, score=-11.4 required=3.0 tests=AWL,BAYES_00,DKIMWL_WL_MED, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_HELO_PASS,SPF_PASS,USER_IN_DEF_DKIM_WL 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 B55E81F8C4 for ; Fri, 5 Feb 2021 20:11:00 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S233565AbhBES2D (ORCPT ); Fri, 5 Feb 2021 13:28:03 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:38810 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S233741AbhBES12 (ORCPT ); Fri, 5 Feb 2021 13:27:28 -0500 Received: from mail-pl1-x64a.google.com (mail-pl1-x64a.google.com [IPv6:2607:f8b0:4864:20::64a]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id AFD63C06174A for ; Fri, 5 Feb 2021 12:09:12 -0800 (PST) Received: by mail-pl1-x64a.google.com with SMTP id y8so5037830plg.5 for ; Fri, 05 Feb 2021 12:09:12 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20161025; h=sender:date:in-reply-to:message-id:mime-version:references:subject :from:to:cc; bh=vGYYnPoEojSG5uquJsJ0BxYbISLULa9+gJdeAFFbwX8=; b=jgE0spBNmHvzrSQCQMBvX1Mi6xwY2tGgcMhQl5u1q9VN633z6jVFETZKh38DwbuvAS 1IzRVmS7nkhGQ7DHY5OKyFXem9WTcX2xGCbmOUp9ysqM1kYYjMRg7NwlzDUMu6Ak6Sf3 HBOZrdMBQWw3dlYom3maiY7PHlU6bVR4EH29dwaOtLSa16Q114Fd+RCrxg7cZIP4u/Ua xIg4PaXkr6mAnhetW7UzLP9epF46cWO/jOWaraR3jqAC1WMaTT9ftcAZ0L1zK6ED57/N 0eXucm69LlSHfrUq5ip7Az0vRVIX8q//vX/KLuFlg0eH52/ouUiqjTeP17Bj5AtL3o5m kJPw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:sender:date:in-reply-to:message-id:mime-version :references:subject:from:to:cc; bh=vGYYnPoEojSG5uquJsJ0BxYbISLULa9+gJdeAFFbwX8=; b=YdkYbahGFvP1b0grO0uc94S/KuJr0GnR9zHbT/ipZJTm1JP2NssI5tOOGTcpYW2DrI nS2jhGMGkiLQElfwcJY6XOeKxhpLOn8px6eBuM6rucn3hlpt/aen/85z5hhMAlpVY0RI 4NSzS2bpLjDdLZEa9ieS6lg1lA7HcYP1Z18KdsTuGgAAgFcOhScrkO5UDUJDYHi0QvRK CdsRa4MHoZsxiCqSUkm/v+kyVhyTjatHhz+5NGdd1CbVy2hG+9Ob0P4QSCbMa/H1dBfK Lt0vNFdj8Tf6f7iOnlbltLERKs/LX0EHsNSppamAKKLY2rsgh39NyuoCwjJygltBh3pY yVGA== X-Gm-Message-State: AOAM5337nAv8PQocVT5jK7g9JZis4LPoGDbuzeJwK9njzPHUAFamdn0K s+QxxHALowIIUdDNIg/AD3oSo7wmrnsX6M1hhNBeogYeRCcVgFonI77Mu57Al0MxlIU5Dgx3ltn +t7SRTsXbFz502FnCrLnvSyYg1l5FNJIPJHSiqWn2V2Km52gjJGtoePbn0zFSPR/NNB+hky/gPR 2n X-Google-Smtp-Source: ABdhPJwcNsKa2BT5kiLj2g5MF52geSBQSacckg4RXUeCzKxvoxaZTs2a471plbjrjml1coEyt0kV2JDMtBhOmcwOlWH7 Sender: "jonathantanmy via sendgmr" X-Received: from twelve4.c.googlers.com ([fda3:e722:ac3:10:24:72f4:c0a8:437a]) (user=jonathantanmy job=sendgmr) by 2002:a63:1865:: with SMTP id 37mr5935669pgy.206.1612555752006; Fri, 05 Feb 2021 12:09:12 -0800 (PST) Date: Fri, 5 Feb 2021 12:09:08 -0800 In-Reply-To: <20210205054914.104640-1-jonathantanmy@google.com> Message-Id: <20210205200908.805639-1-jonathantanmy@google.com> Mime-Version: 1.0 References: <20210205054914.104640-1-jonathantanmy@google.com> X-Mailer: git-send-email 2.30.0.365.g02bc693789-goog Subject: [PATCH v2] usage: trace2 BUG() invocations From: Jonathan Tan To: git@vger.kernel.org Cc: Jonathan Tan , peff@peff.net, stolee@gmail.com, gitster@pobox.com, jeffhost@microsoft.com Content-Type: text/plain; charset="UTF-8" Precedence: bulk List-ID: X-Mailing-List: git@vger.kernel.org die() messages are traced in trace2, but BUG() messages are not. Anyone tracking die() messages would have even more reason to track BUG(). Therefore, write to trace2 when BUG() is invoked. Signed-off-by: Jonathan Tan --- Thanks everyone for your suggestions. I've used an in_bug static variable (which does prevent the infinite loop - I injected the bug that Peff described and verified that it indeed loops without the mitigation and doesn't loop with the mitigation) and moved the trace2 to be below the vreportf (necessitating a va_copy). --- t/helper/test-trace2.c | 9 +++++++++ t/t0210-trace2-normal.sh | 19 +++++++++++++++++++ usage.c | 11 +++++++++++ 3 files changed, 39 insertions(+) diff --git a/t/helper/test-trace2.c b/t/helper/test-trace2.c index 823f33ceff..f93633f895 100644 --- a/t/helper/test-trace2.c +++ b/t/helper/test-trace2.c @@ -198,6 +198,14 @@ static int ut_006data(int argc, const char **argv) return 0; } +static int ut_007bug(int argc, const char **argv) +{ + /* + * Exercise BUG() to ensure that the message is printed to trace2. + */ + BUG("the bug message"); +} + /* * Usage: * test-tool trace2 @@ -214,6 +222,7 @@ static struct unit_test ut_table[] = { { ut_004child, "004child", "[]" }, { ut_005exec, "005exec", "" }, { ut_006data, "006data", "[ ]+" }, + { ut_007bug, "007bug", "" }, }; /* clang-format on */ diff --git a/t/t0210-trace2-normal.sh b/t/t0210-trace2-normal.sh index ce7574edb1..81af180c4c 100755 --- a/t/t0210-trace2-normal.sh +++ b/t/t0210-trace2-normal.sh @@ -147,6 +147,25 @@ test_expect_success 'normal stream, error event' ' test_cmp expect actual ' +# Verb 007bug +# +# Check that BUG writes to trace2 + +test_expect_success 'normal stream, exit code 1' ' + test_when_finished "rm trace.normal actual expect" && + test_must_fail env GIT_TRACE2="$(pwd)/trace.normal" test-tool trace2 007bug && + perl "$TEST_DIRECTORY/t0210/scrub_normal.perl" actual && + cat >expect <<-EOF && + version $V + start _EXE_ trace2 007bug + cmd_name trace2 (trace2) + error the bug message + exit elapsed:_TIME_ code:99 + atexit elapsed:_TIME_ code:99 + EOF + test_cmp expect actual +' + sane_unset GIT_TRACE2_BRIEF # Now test without environment variables and get all Trace2 settings diff --git a/usage.c b/usage.c index 1868a24f7a..1b206de36d 100644 --- a/usage.c +++ b/usage.c @@ -266,6 +266,10 @@ int BUG_exit_code; static NORETURN void BUG_vfl(const char *file, int line, const char *fmt, va_list params) { char prefix[256]; + va_list params_copy; + static int in_bug; + + va_copy(params_copy, params); /* truncation via snprintf is OK here */ if (file) @@ -274,6 +278,13 @@ static NORETURN void BUG_vfl(const char *file, int line, const char *fmt, va_lis snprintf(prefix, sizeof(prefix), "BUG: "); vreportf(prefix, fmt, params); + + if (in_bug) + abort(); + in_bug = 1; + + trace2_cmd_error_va(fmt, params_copy); + if (BUG_exit_code) exit(BUG_exit_code); abort(); -- 2.30.0.365.g02bc693789-goog