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 Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id EBD9DC433EF for ; Fri, 20 May 2022 13:24:34 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1344015AbiETNYc (ORCPT ); Fri, 20 May 2022 09:24:32 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:35520 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1349779AbiETNYY (ORCPT ); Fri, 20 May 2022 09:24:24 -0400 Received: from mga07.intel.com (mga07.intel.com [134.134.136.100]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 9BE551498C4 for ; Fri, 20 May 2022 06:24:22 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1653053062; x=1684589062; h=from:to:cc:subject:date:message-id:in-reply-to: references:mime-version:content-transfer-encoding; bh=U4srRq5yE5CT++6h1AC80Vn5y1NUKDalEuopQN1pxhA=; b=lIh8zbOYfpveYI2JcgGja+iJ70qqdsf8NIugKDFW+V8G9aXhSGPdzRiI 4BZKhRFTPCGpVEkJA53FaeusLQENuvfe0eT7E+SHKBkQVjLnHemS63Kdt G4ktNtwN4/YmydNiBnEste0Y85Wi0sZtlWCZLSzQxAN9eKlaDBeGQc4R1 w2m9BTUaVtrQRYREyluqOGQGetmSiFyisq56rMOON1rUyAGxrVz4czHKL 9dOjTrIUp7aXEbjPW4zl7VAVZYufGtQoQHIT2BBRqnMWYGhj0iFh4O/Sy ZelV0ko5wfiTPWNPal9+PnXLwEkIAgjVjwXu2JmazHHvTtGR+vU6yKKgS g==; X-IronPort-AV: E=McAfee;i="6400,9594,10353"; a="335661013" X-IronPort-AV: E=Sophos;i="5.91,239,1647327600"; d="scan'208";a="335661013" Received: from fmsmga001.fm.intel.com ([10.253.24.23]) by orsmga105.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 20 May 2022 06:24:22 -0700 X-IronPort-AV: E=Sophos;i="5.91,239,1647327600"; d="scan'208";a="715530812" Received: from ahunter6-mobl1.ger.corp.intel.com (HELO ahunter-VirtualBox.home\044ger.corp.intel.com) ([10.252.38.124]) by fmsmga001-auth.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 20 May 2022 06:24:20 -0700 From: Adrian Hunter To: Arnaldo Carvalho de Melo Cc: Jiri Olsa , Namhyung Kim , linux-kernel@vger.kernel.org Subject: [PATCH 2/5] libperf: Add preadn() Date: Fri, 20 May 2022 16:24:01 +0300 Message-Id: <20220520132404.25853-3-adrian.hunter@intel.com> X-Mailer: git-send-email 2.25.1 In-Reply-To: <20220520132404.25853-1-adrian.hunter@intel.com> References: <20220520132404.25853-1-adrian.hunter@intel.com> MIME-Version: 1.0 Organization: Intel Finland Oy, Registered Address: PL 281, 00181 Helsinki, Business Identity Code: 0357606 - 4, Domiciled in Helsinki Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Add preadn() to provide pread() and readn() semantics. Signed-off-by: Adrian Hunter --- tools/lib/perf/include/internal/lib.h | 2 ++ tools/lib/perf/lib.c | 20 ++++++++++++++++++++ 2 files changed, 22 insertions(+) diff --git a/tools/lib/perf/include/internal/lib.h b/tools/lib/perf/include/internal/lib.h index 5175d491b2d4..85471a4b900f 100644 --- a/tools/lib/perf/include/internal/lib.h +++ b/tools/lib/perf/include/internal/lib.h @@ -9,4 +9,6 @@ extern unsigned int page_size; ssize_t readn(int fd, void *buf, size_t n); ssize_t writen(int fd, const void *buf, size_t n); +ssize_t preadn(int fd, void *buf, size_t n, off_t offs); + #endif /* __LIBPERF_INTERNAL_CPUMAP_H */ diff --git a/tools/lib/perf/lib.c b/tools/lib/perf/lib.c index 18658931fc71..ecc8035a3ae3 100644 --- a/tools/lib/perf/lib.c +++ b/tools/lib/perf/lib.c @@ -38,6 +38,26 @@ ssize_t readn(int fd, void *buf, size_t n) return ion(true, fd, buf, n); } +ssize_t preadn(int fd, void *buf, size_t n, off_t offs) +{ + ssize_t ret; + off_t cur; + + cur = lseek(fd, 0, SEEK_CUR); + if (cur < 0) + return -1; + + if (lseek(fd, offs, SEEK_SET) < 0) + return -1; + + ret = readn(fd, buf, n); + + if (lseek(fd, cur, SEEK_CUR) < 0) + return -1; + + return ret; +} + /* * Write exactly 'n' bytes or return an error. */ -- 2.25.1