From patchwork Mon Jun 22 15:13:31 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Florian Weimer X-Patchwork-Id: 39736 Return-Path: X-Original-To: patchwork@sourceware.org Delivered-To: patchwork@sourceware.org Received: from server2.sourceware.org (localhost [IPv6:::1]) by sourceware.org (Postfix) with ESMTP id 1EF6D389043F; Mon, 22 Jun 2020 15:14:02 +0000 (GMT) DKIM-Filter: OpenDKIM Filter v2.11.0 sourceware.org 1EF6D389043F DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=sourceware.org; s=default; t=1592838842; bh=MdMZr0WpLpq+q8le3hipBGbQpiUvjjZCN8FzzrFD4VM=; h=To:Subject:In-Reply-To:References:Date:List-Id:List-Unsubscribe: List-Archive:List-Post:List-Help:List-Subscribe:From:Reply-To: From; b=DGlOWlSIRJB9HmC5rI/4R0Or6XRkI9kfPzwVLnrJAzN2fL6dWxpIR8RF2nFQi40fz k+t1lf6GSdNFoSTuTG6KLN1ls2MwnnANO3KbVPN2rC8fAML8SXXkxLV0hM9KKtZ8Ek 7MznC04x5Jn6Ekmr0NKm5KDGBkJs0IeyUMhuxeqI= X-Original-To: libc-alpha@sourceware.org Delivered-To: libc-alpha@sourceware.org Received: from us-smtp-delivery-1.mimecast.com (us-smtp-2.mimecast.com [205.139.110.61]) by sourceware.org (Postfix) with ESMTP id BF14B388B033 for ; Mon, 22 Jun 2020 15:13:59 +0000 (GMT) DMARC-Filter: OpenDMARC Filter v1.3.2 sourceware.org BF14B388B033 Received: from mimecast-mx01.redhat.com (mimecast-mx01.redhat.com [209.132.183.4]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-134-fP3M2XTtM3qz8cL29Y1Neg-1; Mon, 22 Jun 2020 11:13:47 -0400 X-MC-Unique: fP3M2XTtM3qz8cL29Y1Neg-1 Received: from smtp.corp.redhat.com (int-mx02.intmail.prod.int.phx2.redhat.com [10.5.11.12]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id 279D585B681 for ; Mon, 22 Jun 2020 15:13:33 +0000 (UTC) Received: from oldenburg2.str.redhat.com (ovpn-112-185.ams2.redhat.com [10.36.112.185]) by smtp.corp.redhat.com (Postfix) with ESMTPS id 73AFE60BE2 for ; Mon, 22 Jun 2020 15:13:32 +0000 (UTC) To: libc-alpha@sourceware.org Subject: [PATCH 05/30] elf: Implement _dl_write In-Reply-To: References: Message-Id: <9ee184e1faa8be2edf3d8174b64ebb57aedd8294.1592836143.git.fweimer@redhat.com> Date: Mon, 22 Jun 2020 17:13:31 +0200 User-Agent: Gnus/5.13 (Gnus v5.13) Emacs/26.3 (gnu/linux) MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.79 on 10.5.11.12 X-Mimecast-Spam-Score: 0 X-Mimecast-Originator: redhat.com X-Spam-Status: No, score=-12.9 required=5.0 tests=BAYES_00, DKIMWL_WL_HIGH, DKIM_SIGNED, DKIM_VALID, DKIM_VALID_AU, DKIM_VALID_EF, GIT_PATCH_0, KAM_SHORT, RCVD_IN_DNSWL_NONE, RCVD_IN_MSPIKE_H3, RCVD_IN_MSPIKE_WL, SPF_HELO_NONE, SPF_PASS, TXREP autolearn=ham autolearn_force=no version=3.4.2 X-Spam-Checker-Version: SpamAssassin 3.4.2 (2018-09-13) on server2.sourceware.org X-BeenThere: libc-alpha@sourceware.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Libc-alpha mailing list List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-Patchwork-Original-From: Florian Weimer via Libc-alpha From: Florian Weimer Reply-To: Florian Weimer Errors-To: libc-alpha-bounces@sourceware.org Sender: "Libc-alpha" The generic version is parallel to _dl_writev. It cannot use _dl_writev directly because the errno value needs to be obtained under a lock. --- elf/Makefile | 2 +- elf/dl-write.c | 56 ++++++++++++++++++++++++++++++ sysdeps/generic/ldsodefs.h | 6 ++++ sysdeps/unix/sysv/linux/dl-write.c | 30 ++++++++++++++++ 4 files changed, 93 insertions(+), 1 deletion(-) create mode 100644 elf/dl-write.c create mode 100644 sysdeps/unix/sysv/linux/dl-write.c diff --git a/elf/Makefile b/elf/Makefile index 1293de5b5e..b56fe0c0b7 100644 --- a/elf/Makefile +++ b/elf/Makefile @@ -34,7 +34,7 @@ dl-routines = $(addprefix dl-,load lookup object reloc deps \ version profile tls origin scope \ execstack open close trampoline \ exception sort-maps lookup-direct \ - call-libc-early-init) + call-libc-early-init write) ifeq (yes,$(use-ldconfig)) dl-routines += dl-cache endif diff --git a/elf/dl-write.c b/elf/dl-write.c new file mode 100644 index 0000000000..7350aff003 --- /dev/null +++ b/elf/dl-write.c @@ -0,0 +1,56 @@ +/* Implementation of the _dl_write function. Generic version. + Copyright (C) 2020 Free Software Foundation, Inc. + This file is part of the GNU C Library. + + The GNU C Library is free software; you can redistribute it and/or + modify it under the terms of the GNU Lesser General Public + License as published by the Free Software Foundation; either + version 2.1 of the License, or (at your option) any later version. + + The GNU C Library is distributed in the hope that it will be useful, + but WITHOUT ANY WARRANTY; without even the implied warranty of + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU + Lesser General Public License for more details. + + You should have received a copy of the GNU Lesser General Public + License along with the GNU C Library; if not, see + . */ + +#include +#include +#include +#include + +ssize_t +_dl_write (int fd, const void *buffer, size_t length) +{ + struct iovec iov = { .iov_base = (void *) buffer, .iov_len = length }; + ssize_t ret; + +#if RTLD_PRIVATE_ERRNO + /* We have to take this lock just to be sure we don't clobber the private + errno when it's being used by another thread that cares about it. + Yet we must be sure not to try calling the lock functions before + the thread library is fully initialized. */ + if (__glibc_unlikely (_dl_starting_up)) + { + ret = __writev (fd, &iov, 1); + if (ret < 0) + ret = -errno; + } + else + { + __rtld_lock_lock_recursive (GL(dl_load_lock)); + __writev (fd, &iov, 1); + if (ret < 0) + ret = -errno; + __rtld_lock_unlock_recursive (GL(dl_load_lock)); + } +#else + ret = __writev (fd, &iov, 1); + if (ret < 0) + ret = -errno; +#endif + + return ret; +} diff --git a/sysdeps/generic/ldsodefs.h b/sysdeps/generic/ldsodefs.h index d08b97a5ef..42fe912f47 100644 --- a/sysdeps/generic/ldsodefs.h +++ b/sysdeps/generic/ldsodefs.h @@ -749,6 +749,12 @@ _dl_dprintf (int fd, const char *fmt, ...) } #endif +/* Write LENGTH bytes at BUFFER to FD, like write. Returns the number + of bytes written on success, or a negative error constant on + failure. */ +ssize_t _dl_write (int fd, const void *buffer, size_t length) + attribute_hidden; + /* Write a message on the specified descriptor standard output. The parameters are interpreted as for a `printf' call. */ void _dl_printf (const char *fmt, ...) diff --git a/sysdeps/unix/sysv/linux/dl-write.c b/sysdeps/unix/sysv/linux/dl-write.c new file mode 100644 index 0000000000..1c6298fb41 --- /dev/null +++ b/sysdeps/unix/sysv/linux/dl-write.c @@ -0,0 +1,30 @@ +/* Implementation of the _dl_write function. Linux version. + Copyright (C) 2020 Free Software Foundation, Inc. + This file is part of the GNU C Library. + + The GNU C Library is free software; you can redistribute it and/or + modify it under the terms of the GNU Lesser General Public + License as published by the Free Software Foundation; either + version 2.1 of the License, or (at your option) any later version. + + The GNU C Library is distributed in the hope that it will be useful, + but WITHOUT ANY WARRANTY; without even the implied warranty of + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU + Lesser General Public License for more details. + + You should have received a copy of the GNU Lesser General Public + License along with the GNU C Library; if not, see + . */ + +#include +#include +#include + +ssize_t +_dl_write (int fd, const void *buffer, size_t length) +{ + long int r = INTERNAL_SYSCALL_CALL (write, fd, buffer, length); + if (INTERNAL_SYSCALL_ERROR_P (r)) + r = - INTERNAL_SYSCALL_ERRNO (r); + return r; +}