From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-9.8 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS,UNWANTED_LANGUAGE_BODY,USER_AGENT_GIT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 3AE37C00A89 for ; Thu, 5 Nov 2020 09:34:05 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id D2AE620825 for ; Thu, 5 Nov 2020 09:34:04 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="jng7xet6" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1730977AbgKEJeE (ORCPT ); Thu, 5 Nov 2020 04:34:04 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:54730 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1730933AbgKEJeE (ORCPT ); Thu, 5 Nov 2020 04:34:04 -0500 Received: from mail-ed1-x544.google.com (mail-ed1-x544.google.com [IPv6:2a00:1450:4864:20::544]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 002A9C0613CF for ; Thu, 5 Nov 2020 01:34:03 -0800 (PST) Received: by mail-ed1-x544.google.com with SMTP id q3so527290edr.12 for ; Thu, 05 Nov 2020 01:34:03 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=from:to:cc:subject:date:message-id:in-reply-to:references :mime-version:content-transfer-encoding; bh=ZCaXfC9bAFsWhp/F+Cok4+r6l6pigKOO6lV5zVTECOc=; b=jng7xet6bWh6Y+bFJkjDgGoIWPpZEtRPqgSOE+4tQXcvpcQL6oB7PO85SyKoDqpaV2 CpL3njNvJFSCalXOUC0njnIvPeCmv2lz2flIfVaCbT1m6pjZopCIQCcCmyusoboyvlkx rTv6RSQDG4xFmiC8RDPHibB+YJy/I94iDQGGhlONpAQ0dWvGZsygMH7bGU+peXjVE6BL mAOpdzscM/TprqdMapJOTkEF4/gq2eO1QUYkYBCwI+0yI34gWHNNnTENWoEye9REV6Uj kkS75Eag+tpFpClTYNFkEtO/dqphUDFbJgUojRg51q9ZfEd0N/rH5eXAo9fO7DV/nNHl b6uA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:to:cc:subject:date:message-id:in-reply-to :references:mime-version:content-transfer-encoding; bh=ZCaXfC9bAFsWhp/F+Cok4+r6l6pigKOO6lV5zVTECOc=; b=XvgyxhTX9rhnLoVkmZBcP1VNukl/Z0xQbBNcb1Bn0nrmqwVs76Im/pUDNdfkUEr0Yt YuVPhKUg+5RV236NolCt9KSSuJxRKKif/bWt0bDEkMI6XmiYgzGMDjXCW44Neyvq4tAu 23g9jPkKGzn4IVwDGI4JoyYc1ab9h7rd/tsFsLpKICykQr3SvrdIWZD5tSMSLWNhEo9/ 2I134bzpGF0E2O1NL859tU+CT2uywbg5tNzvJVapkRhvPbmMyr353zk5y8VnKeuLF4iW 1Zyrjf8FXpMT/1sBLlDMMD6loG9Kfy92eZOEgGllxJ1zOq/H80V/LxTqEsgD/40kojxt mPag== X-Gm-Message-State: AOAM531CcTzrf8QJtu8WnBlugqORpKBGPa0WpzyzJLPIKd+q49hR1ck6 DRCyDTPIjyBmP5brJuMlh6k= X-Google-Smtp-Source: ABdhPJzas748hp51V3//mc3/hoblbwNboSCUYKyXBPrMFl9UvSFgiCSf0XcHb0VICdLE0+v61qcRFQ== X-Received: by 2002:a50:eb45:: with SMTP id z5mr1622078edp.144.1604568842779; Thu, 05 Nov 2020 01:34:02 -0800 (PST) Received: from localhost.localdomain ([83.222.187.186]) by smtp.gmail.com with ESMTPSA id 1sm586725ejt.107.2020.11.05.01.34.01 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Thu, 05 Nov 2020 01:34:02 -0800 (PST) From: "Tzvetomir Stoyanov (VMware)" To: rostedt@goodmis.org Cc: linux-trace-devel@vger.kernel.org Subject: [PATCH 3/6] libtracefs: Add new API to check if instance exists Date: Thu, 5 Nov 2020 11:33:51 +0200 Message-Id: <20201105093354.532742-4-tz.stoyanov@gmail.com> X-Mailer: git-send-email 2.28.0 In-Reply-To: <20201105093354.532742-1-tz.stoyanov@gmail.com> References: <20201105093354.532742-1-tz.stoyanov@gmail.com> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-trace-devel@vger.kernel.org A new API is implemented: tracefs_instance_exists() which can be used to check if ftrace instance with given name exists in the system. Signed-off-by: Tzvetomir Stoyanov (VMware) --- include/tracefs/tracefs.h | 1 + lib/tracefs/tracefs-instance.c | 22 +++++++++++++++++++++- utest/tracefs-utest.c | 2 ++ 3 files changed, 24 insertions(+), 1 deletion(-) diff --git a/include/tracefs/tracefs.h b/include/tracefs/tracefs.h index 8d193853..e5bf3df4 100644 --- a/include/tracefs/tracefs.h +++ b/include/tracefs/tracefs.h @@ -33,6 +33,7 @@ int tracefs_instance_file_write(struct tracefs_instance *instance, char *tracefs_instance_file_read(struct tracefs_instance *instance, char *file, int *psize); +bool tracefs_instance_exists(const char *name); bool tracefs_file_exists(struct tracefs_instance *instance, char *name); bool tracefs_dir_exists(struct tracefs_instance *instance, char *name); diff --git a/lib/tracefs/tracefs-instance.c b/lib/tracefs/tracefs-instance.c index e9ec3401..c19dd3b4 100644 --- a/lib/tracefs/tracefs-instance.c +++ b/lib/tracefs/tracefs-instance.c @@ -257,7 +257,10 @@ static bool check_file_exists(struct tracefs_instance *instance, int ret; path = tracefs_instance_get_dir(instance); - snprintf(file, PATH_MAX, "%s/%s", path, name); + if (name) + snprintf(file, PATH_MAX, "%s/%s", path, name); + else + snprintf(file, PATH_MAX, "%s", path); tracefs_put_tracing_file(path); ret = stat(file, &st); if (ret < 0) @@ -266,6 +269,23 @@ static bool check_file_exists(struct tracefs_instance *instance, return !dir == !S_ISDIR(st.st_mode); } +/** + * tracefs_instance_exists - Check an instance with given name exists + * @name: name of the instance + * + * Returns true if the instance exists, false otherwise + * + */ +bool tracefs_instance_exists(const char *name) +{ + char file[PATH_MAX]; + + if (!name) + return false; + snprintf(file, PATH_MAX, "instances/%s", name); + return check_file_exists(NULL, file, true); +} + /** * tracefs_file_exists - Check if a file with given name exists in given instance * @instance: ftrace instance, can be NULL for the top instance diff --git a/utest/tracefs-utest.c b/utest/tracefs-utest.c index 31a700ff..292bcab0 100644 --- a/utest/tracefs-utest.c +++ b/utest/tracefs-utest.c @@ -197,6 +197,7 @@ static void test_instance_file(void) CU_TEST(asprintf(&inst_dir, "%s/instances/%s", tdir, name) > 0); CU_TEST(stat(inst_dir, &st) != 0); + CU_TEST(tracefs_instance_exists(name) == false); instance = tracefs_instance_alloc(name); CU_TEST(instance != NULL); CU_TEST(stat(inst_dir, &st) != 0); @@ -205,6 +206,7 @@ static void test_instance_file(void) CU_TEST(strcmp(inst_name, name) == 0); CU_TEST(tracefs_instance_create(instance) == 0); + CU_TEST(tracefs_instance_exists(name) == true); CU_TEST(stat(inst_dir, &st) == 0); CU_TEST(S_ISDIR(st.st_mode)); -- 2.28.0