From owner-svn-src-head@freebsd.org  Tue Oct 24 12:04:09 2017
Return-Path: <owner-svn-src-head@freebsd.org>
Delivered-To: svn-src-head@mailman.ysv.freebsd.org
Received: from mx1.freebsd.org (mx1.freebsd.org
 [IPv6:2001:1900:2254:206a::19:1])
 by mailman.ysv.freebsd.org (Postfix) with ESMTP id 12E14E4B1F5;
 Tue, 24 Oct 2017 12:04:09 +0000 (UTC)
 (envelope-from trasz@FreeBSD.org)
Received: from repo.freebsd.org (repo.freebsd.org
 [IPv6:2610:1c1:1:6068::e6a:0])
 (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits))
 (Client did not present a certificate)
 by mx1.freebsd.org (Postfix) with ESMTPS id D51D180FB0;
 Tue, 24 Oct 2017 12:04:08 +0000 (UTC)
 (envelope-from trasz@FreeBSD.org)
Received: from repo.freebsd.org ([127.0.1.37])
 by repo.freebsd.org (8.15.2/8.15.2) with ESMTP id v9OC48cj031365;
 Tue, 24 Oct 2017 12:04:08 GMT (envelope-from trasz@FreeBSD.org)
Received: (from trasz@localhost)
 by repo.freebsd.org (8.15.2/8.15.2/Submit) id v9OC48oO031364;
 Tue, 24 Oct 2017 12:04:08 GMT (envelope-from trasz@FreeBSD.org)
Message-Id: <201710241204.v9OC48oO031364@repo.freebsd.org>
X-Authentication-Warning: repo.freebsd.org: trasz set sender to
 trasz@FreeBSD.org using -f
From: Edward Tomasz Napierala <trasz@FreeBSD.org>
Date: Tue, 24 Oct 2017 12:04:07 +0000 (UTC)
To: src-committers@freebsd.org, svn-src-all@freebsd.org,
 svn-src-head@freebsd.org
Subject: svn commit: r324952 - head/libexec/rtld-elf
X-SVN-Group: head
X-SVN-Commit-Author: trasz
X-SVN-Commit-Paths: head/libexec/rtld-elf
X-SVN-Commit-Revision: 324952
X-SVN-Commit-Repository: base
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit
X-BeenThere: svn-src-head@freebsd.org
X-Mailman-Version: 2.1.23
Precedence: list
List-Id: SVN commit messages for the src tree for head/-current
 <svn-src-head.freebsd.org>
List-Unsubscribe: <https://lists.freebsd.org/mailman/options/svn-src-head>,
 <mailto:svn-src-head-request@freebsd.org?subject=unsubscribe>
List-Archive: <http://lists.freebsd.org/pipermail/svn-src-head/>
List-Post: <mailto:svn-src-head@freebsd.org>
List-Help: <mailto:svn-src-head-request@freebsd.org?subject=help>
List-Subscribe: <https://lists.freebsd.org/mailman/listinfo/svn-src-head>,
 <mailto:svn-src-head-request@freebsd.org?subject=subscribe>
X-List-Received-Date: Tue, 24 Oct 2017 12:04:09 -0000

Author: trasz
Date: Tue Oct 24 12:04:07 2017
New Revision: 324952
URL: https://svnweb.freebsd.org/changeset/base/324952

Log:
  Replace lseek(2)/read(2) pair with pread(2), removing yet another syscall
  from the binary startup code.
  
  MFC after:	2 weeks
  Sponsored by:	DARPA, AFRL

Modified:
  head/libexec/rtld-elf/rtld.c

Modified: head/libexec/rtld-elf/rtld.c
==============================================================================
--- head/libexec/rtld-elf/rtld.c	Tue Oct 24 11:24:54 2017	(r324951)
+++ head/libexec/rtld-elf/rtld.c	Tue Oct 24 12:04:07 2017	(r324952)
@@ -1824,10 +1824,9 @@ cleanup1:
 		if (dl > hint_stat.st_size)
 			goto cleanup1;
 		p = xmalloc(hdr.dirlistlen + 1);
-
-		if (lseek(fd, hdr.strtab + hdr.dirlist, SEEK_SET) == -1 ||
-		    read(fd, p, hdr.dirlistlen + 1) !=
-		    (ssize_t)hdr.dirlistlen + 1 || p[hdr.dirlistlen] != '\0') {
+		if (pread(fd, p, hdr.dirlistlen + 1,
+		    hdr.strtab + hdr.dirlist) != (ssize_t)hdr.dirlistlen + 1 ||
+		    p[hdr.dirlistlen] != '\0') {
 			free(p);
 			goto cleanup1;
 		}