From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (qmail 84622 invoked by alias); 2 Apr 2018 13:59:40 -0000 Mailing-List: contact libc-alpha-help@sourceware.org; run by ezmlm Precedence: bulk List-Id: List-Subscribe: List-Archive: List-Post: List-Help: , Sender: libc-alpha-owner@sourceware.org Received: (qmail 84587 invoked by uid 89); 2 Apr 2018 13:59:39 -0000 Authentication-Results: sourceware.org; auth=none X-Virus-Found: No X-Spam-SWARE-Status: No, score=-26.9 required=5.0 tests=BAYES_00,GIT_PATCH_0,GIT_PATCH_1,GIT_PATCH_2,GIT_PATCH_3,KAM_SHORT,RCVD_IN_DNSWL_NONE,SPF_PASS autolearn=ham version=3.3.2 spammy=HX-HELO:sk:mail-qk, H*r:sk:mail-qk, Hx-spam-relays-external:sk:mail-qk, H*RU:sk:mail-qk X-HELO: mail-qk0-f193.google.com X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:subject:from:to:references:openpgp:autocrypt :message-id:date:user-agent:mime-version:in-reply-to :content-language:content-transfer-encoding; bh=6+SpIvCFNV0nkvIqxj2clK0ZOW4hiam32zrXs57vGJI=; b=SU+JaHNhJ2BtrNP5I5+OqH5fkQAHCb14SQhvj0fYmx8lkYsWHMlNFvLI7S/wVVeq4u FwD9U+DdsiiLsDrWfLV/FcK+m3Xyi+7ssb+27QWIjbGxxBNXyNV8BXZjVyCRuf/eY6Q/ NRvAPQrWAEmf+QJGETLCecgKAupqwQ0qRuMjnS9gGZbTjrINB/M2cZt1/F2sieDPKeT4 /H1KDJOe/YH8S92Lvw0RtxaqwKgvmbvbnVXo1Wla4wdYQBLfECe9GTiVOIM6CyY4NaF9 xw3rxHFX54ec/H84bYxrOREvYdXq3Gquza3FpR9QFPT5qffBGiHV/Ng6ZDXtINdjKyhQ hHTA== X-Gm-Message-State: ALQs6tAL42NKb2HnpFGGBz/RxASidjqBE6oQ3IH63Su3XNaU7snK4Gw/ g2aiATOEF/1UOBPZTvPLF/EFs5aELa4= X-Google-Smtp-Source: AIpwx48SNpkBdfaZJLEjDQGvD90tQJOJl9G2W+cFDUConUcmA5zlq9biH62f068po/qYZij4ClR+wA== X-Received: by 10.55.167.5 with SMTP id q5mr12685494qke.273.1522677575712; Mon, 02 Apr 2018 06:59:35 -0700 (PDT) Subject: Re: [PATCH 1/7] Assume O_DIRECTORY for opendir From: Adhemerval Zanella To: libc-alpha@sourceware.org References: <1520017165-15830-1-git-send-email-adhemerval.zanella@linaro.org> Openpgp: preference=signencrypt Autocrypt: addr=adhemerval.zanella@linaro.org; keydata= xsFNBFcVGkoBEADiQU2x/cBBmAVf5C2d1xgz6zCnlCefbqaflUBw4hB/bEME40QsrVzWZ5Nq 8kxkEczZzAOKkkvv4pRVLlLn/zDtFXhlcvQRJ3yFMGqzBjofucOrmdYkOGo0uCaoJKPT186L NWp53SACXguFJpnw4ODI64ziInzXQs/rUJqrFoVIlrPDmNv/LUv1OVPKz20ETjgfpg8MNwG6 iMizMefCl+RbtXbIEZ3TE/IaDT/jcOirjv96lBKrc/pAL0h/O71Kwbbp43fimW80GhjiaN2y WGByepnkAVP7FyNarhdDpJhoDmUk9yfwNuIuESaCQtfd3vgKKuo6grcKZ8bHy7IXX1XJj2X/ BgRVhVgMHAnDPFIkXtP+SiarkUaLjGzCz7XkUn4XAGDskBNfbizFqYUQCaL2FdbW3DeZqNIa nSzKAZK7Dm9+0VVSRZXP89w71Y7JUV56xL/PlOE+YKKFdEw+gQjQi0e+DZILAtFjJLoCrkEX w4LluMhYX/X8XP6/C3xW0yOZhvHYyn72sV4yJ1uyc/qz3OY32CRy+bwPzAMAkhdwcORA3JPb kPTlimhQqVgvca8m+MQ/JFZ6D+K7QPyvEv7bQ7M+IzFmTkOCwCJ3xqOD6GjX3aphk8Sr0dq3 4Awlf5xFDAG8dn8Uuutb7naGBd/fEv6t8dfkNyzj6yvc4jpVxwARAQABzUlBZGhlbWVydmFs IFphbmVsbGEgTmV0dG8gKExpbmFybyBWUE4gS2V5KSA8YWRoZW1lcnZhbC56YW5lbGxhQGxp bmFyby5vcmc+wsF3BBMBCAAhBQJXFRpKAhsDBQsJCAcDBRUKCQgLBRYCAwEAAh4BAheAAAoJ EKqx7BSnlIjv0e8P/1YOYoNkvJ+AJcNUaM5a2SA9oAKjSJ/M/EN4Id5Ow41ZJS4lUA0apSXW NjQg3VeVc2RiHab2LIB4MxdJhaWTuzfLkYnBeoy4u6njYcaoSwf3g9dSsvsl3mhtuzm6aXFH /Qsauav77enJh99tI4T+58rp0EuLhDsQbnBic/ukYNv7sQV8dy9KxA54yLnYUFqH6pfH8Lly sTVAMyi5Fg5O5/hVV+Z0Kpr+ZocC1YFJkTsNLAW5EIYSP9ftniqaVsim7MNmodv/zqK0IyDB GLLH1kjhvb5+6ySGlWbMTomt/or/uvMgulz0bRS+LUyOmlfXDdT+t38VPKBBVwFMarNuREU2 69M3a3jdTfScboDd2ck1u7l+QbaGoHZQ8ZNUrzgObltjohiIsazqkgYDQzXIMrD9H19E+8fw kCNUlXxjEgH/Kg8DlpoYJXSJCX0fjMWfXywL6ZXc2xyG/hbl5hvsLNmqDpLpc1CfKcA0BkK+ k8R57fr91mTCppSwwKJYO9T+8J+o4ho/CJnK/jBy1pWKMYJPvvrpdBCWq3MfzVpXYdahRKHI ypk8m4QlRlbOXWJ3TDd/SKNfSSrWgwRSg7XCjSlR7PNzNFXTULLB34sZhjrN6Q8NQZsZnMNs TX8nlGOVrKolnQPjKCLwCyu8PhllU8OwbSMKskcD1PSkG6h3r0AqzsFNBFcVGkoBEACgAdbR Ck+fsfOVwT8zowMiL3l9a2DP3Eeak23ifdZG+8Avb/SImpv0UMSbRfnw/N81IWwlbjkjbGTu oT37iZHLRwYUFmA8fZX0wNDNKQUUTjN6XalJmvhdz9l71H3WnE0wneEM5ahu5V1L1utUWTyh VUwzX1lwJeV3vyrNgI1kYOaeuNVvq7npNR6t6XxEpqPsNc6O77I12XELic2+36YibyqlTJIQ V1SZEbIy26AbC2zH9WqaKyGyQnr/IPbTJ2Lv0dM3RaXoVf+CeK7gB2B+w1hZummD21c1Laua +VIMPCUQ+EM8W9EtX+0iJXxI+wsztLT6vltQcm+5Q7tY+HFUucizJkAOAz98YFucwKefbkTp eKvCfCwiM1bGatZEFFKIlvJ2QNMQNiUrqJBlW9nZp/k7pbG3oStOjvawD9ZbP9e0fnlWJIsj 6c7pX354Yi7kxIk/6gREidHLLqEb/otuwt1aoMPg97iUgDV5mlNef77lWE8vxmlY0FBWIXuZ yv0XYxf1WF6dRizwFFbxvUZzIJp3spAao7jLsQj1DbD2s5+S1BW09A0mI/1DjB6EhNN+4bDB SJCOv/ReK3tFJXuj/HbyDrOdoMt8aIFbe7YFLEExHpSk+HgN05Lg5TyTro8oW7TSMTk+8a5M kzaH4UGXTTBDP/g5cfL3RFPl79ubXwARAQABwsFfBBgBCAAJBQJXFRpKAhsMAAoJEKqx7BSn lIjvI/8P/jg0jl4Tbvg3B5kT6PxJOXHYu9OoyaHLcay6Cd+ZrOd1VQQCbOcgLFbf4Yr+rE9l mYsY67AUgq2QKmVVbn9pjvGsEaz8UmfDnz5epUhDxC6yRRvY4hreMXZhPZ1pbMa6A0a/WOSt AgFj5V6Z4dXGTM/lNManr0HjXxbUYv2WfbNt3/07Db9T+GZkpUotC6iknsTA4rJi6u2ls0W9 1UIvW4o01vb4nZRCj4rni0g6eWoQCGoVDk/xFfy7ZliR5B+3Z3EWRJcQskip/QAHjbLa3pml xAZ484fVxgeESOoaeC9TiBIp0NfH8akWOI0HpBCiBD5xaCTvR7ujUWMvhsX2n881r/hNlR9g fcE6q00qHSPAEgGr1bnFv74/1vbKtjeXLCcRKk3Ulw0bY1OoDxWQr86T2fZGJ/HIZuVVBf3+ gaYJF92GXFynHnea14nFFuFgOni0Mi1zDxYH/8yGGBXvo14KWd8JOW0NJPaCDFJkdS5hu0VY 7vJwKcyHJGxsCLU+Et0mryX8qZwqibJIzu7kUJQdQDljbRPDFd/xmGUFCQiQAncSilYOcxNU EMVCXPAQTteqkvA+gNqSaK1NM9tY0eQ4iJpo+aoX8HAcn4sZzt2pfUB9vQMTBJ2d4+m/qO6+ cFTAceXmIoFsN8+gFN3i8Is3u12u8xGudcBPvpoy4OoG Message-ID: <584bd91b-4d69-2533-97de-fede16316eec@linaro.org> Date: Mon, 02 Apr 2018 13:59:00 -0000 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:52.0) Gecko/20100101 Thunderbird/52.6.0 MIME-Version: 1.0 In-Reply-To: <1520017165-15830-1-git-send-email-adhemerval.zanella@linaro.org> Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 7bit X-SW-Source: 2018-04/txt/msg00011.txt.bz2 On 02/03/2018 15:59, Adhemerval Zanella wrote: > This patch assumes O_DIRECTORY works as defined by POSIX on opendir > implementation (aligning with other glibc code, for instance pwd). This > allows remove both the fallback code to handle system with missing or > broken O_DIRECTORY along with the Linux specific opendir.c which just > advertise the working flag. > > Checked on aarch64-linux-gnu, x86_64-linux-gnu, i686-linux-gnu, > sparcv9-linux-gnu, sparc64-linux-gnu, powerpc-linux-gnu, and > powerpc64le-linux-gnu. > > * sysdeps/posix/opendir.c (o_directory_works, tryopen_o_directory): > Remove definitions. > (opendir_oflags): Use O_DIRECTORY regardless. > (__opendir, __opendirat): Remove need_isdir_precheck usage. > * sysdeps/unix/sysv/linux/opendir.c: Remove file. If no one opposes it I will commit this shortly. > --- > ChangeLog | 8 +++ > sysdeps/posix/opendir.c | 108 ++------------------------------------ > sysdeps/unix/sysv/linux/opendir.c | 20 ------- > 3 files changed, 13 insertions(+), 123 deletions(-) > delete mode 100644 sysdeps/unix/sysv/linux/opendir.c > > diff --git a/sysdeps/posix/opendir.c b/sysdeps/posix/opendir.c > index d925804..dea23b2 100644 > --- a/sysdeps/posix/opendir.c > +++ b/sysdeps/posix/opendir.c > @@ -15,24 +15,13 @@ > License along with the GNU C Library; if not, see > . */ > > -#include > -#include > -#include > -#include > -#include > -#include > #include > #include > -#include > -#include > -#include > -#include > -#include > -#include > - > -#include > +#include > +#include /* For BUFSIZ. */ > +#include /* For MIN and MAX. */ > + > #include > -#include > > /* The st_blksize value of the directory is used as a hint for the > size of the buffer which receives struct dirent values from the > @@ -40,49 +29,8 @@ > file system provides a bogus value. */ > #define MAX_DIR_BUFFER_SIZE 1048576U > > -/* opendir() must not accidentally open something other than a directory. > - Some OS's have kernel support for that, some don't. In the worst > - case we have to stat() before the open() AND fstat() after. > - > - We have to test at runtime for kernel support since libc may have > - been compiled with different headers to the kernel it's running on. > - This test can't be done reliably in the general case. We'll use > - /dev/null, which if it's not a device lots of stuff will break, as > - a guinea pig. It may be missing in chroot environments, so we > - make sure to fail safe. */ > -#ifdef O_DIRECTORY > -# ifdef O_DIRECTORY_WORKS > -# define o_directory_works 1 > -# define tryopen_o_directory() while (1) /* This must not be called. */ > -# else > -static int o_directory_works; > - > -static void > -tryopen_o_directory (void) > -{ > - int serrno = errno; > - int x = __open_nocancel ("/dev/null", O_RDONLY|O_NDELAY|O_DIRECTORY); > - > - if (x >= 0) > - { > - __close_nocancel_nostatus (x); > - o_directory_works = -1; > - } > - else if (errno != ENOTDIR) > - o_directory_works = -1; > - else > - o_directory_works = 1; > - > - __set_errno (serrno); > -} > -# endif > -# define EXTRA_FLAGS O_DIRECTORY > -#else > -# define EXTRA_FLAGS 0 > -#endif > - > enum { > - opendir_oflags = O_RDONLY|O_NDELAY|EXTRA_FLAGS|O_LARGEFILE|O_CLOEXEC > + opendir_oflags = O_RDONLY|O_NDELAY|O_DIRECTORY|O_LARGEFILE|O_CLOEXEC > }; > > static bool > @@ -98,21 +46,6 @@ invalid_name (const char *name) > return false; > } > > - > -static bool > -need_isdir_precheck (void) > -{ > -#ifdef O_DIRECTORY > - /* Test whether O_DIRECTORY works. */ > - if (o_directory_works == 0) > - tryopen_o_directory (); > - > - /* We can skip the expensive `stat' call if O_DIRECTORY works. */ > - return o_directory_works < 0; > -#endif > - return true; > -} > - > static DIR * > opendir_tail (int fd) > { > @@ -144,22 +77,6 @@ __opendirat (int dfd, const char *name) > if (__glibc_unlikely (invalid_name (name))) > return NULL; > > - if (need_isdir_precheck ()) > - { > - /* We first have to check whether the name is for a directory. We > - cannot do this after the open() call since the open/close operation > - performed on, say, a tape device might have undesirable effects. */ > - struct stat64 statbuf; > - if (__glibc_unlikely (__fxstatat64 (_STAT_VER, dfd, name, > - &statbuf, 0) < 0)) > - return NULL; > - if (__glibc_unlikely (! S_ISDIR (statbuf.st_mode))) > - { > - __set_errno (ENOTDIR); > - return NULL; > - } > - } > - > return opendir_tail (__openat_nocancel (dfd, name, opendir_oflags)); > } > #endif > @@ -172,21 +89,6 @@ __opendir (const char *name) > if (__glibc_unlikely (invalid_name (name))) > return NULL; > > - if (need_isdir_precheck ()) > - { > - /* We first have to check whether the name is for a directory. We > - cannot do this after the open() call since the open/close operation > - performed on, say, a tape device might have undesirable effects. */ > - struct stat64 statbuf; > - if (__glibc_unlikely (__xstat64 (_STAT_VER, name, &statbuf) < 0)) > - return NULL; > - if (__glibc_unlikely (! S_ISDIR (statbuf.st_mode))) > - { > - __set_errno (ENOTDIR); > - return NULL; > - } > - } > - > return opendir_tail (__open_nocancel (name, opendir_oflags)); > } > weak_alias (__opendir, opendir) > diff --git a/sysdeps/unix/sysv/linux/opendir.c b/sysdeps/unix/sysv/linux/opendir.c > deleted file mode 100644 > index 2677253..0000000 > --- a/sysdeps/unix/sysv/linux/opendir.c > +++ /dev/null > @@ -1,20 +0,0 @@ > -/* Copyright (C) 2000-2018 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 > - . */ > - > -#define O_DIRECTORY_WORKS 1 > - > -#include >