From patchwork Fri Apr 17 13:22:02 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Adhemerval Zanella Netto X-Patchwork-Id: 38822 Return-Path: X-Original-To: libc-alpha@sourceware.org Delivered-To: libc-alpha@sourceware.org Received: from mail-qv1-xf41.google.com (mail-qv1-xf41.google.com [IPv6:2607:f8b0:4864:20::f41]) by sourceware.org (Postfix) with ESMTPS id 8F1B8385DC08 for ; Fri, 17 Apr 2020 13:22:18 +0000 (GMT) DMARC-Filter: OpenDMARC Filter v1.3.2 sourceware.org 8F1B8385DC08 Received: by mail-qv1-xf41.google.com with SMTP id v18so822971qvx.9 for ; Fri, 17 Apr 2020 06:22:18 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:to:subject:date:message-id:in-reply-to :references; bh=jPydN9YIsNs5Fy6f5zR33KsrU9VH+ex2Ii1z+2Cva3k=; b=ui1km3dkVl/m8x8jB0UFu5wFL5cj2qzRcUm+WMe7RVCU1v5NbOTfdfhU6A/QfdRoIN Gea2uNB+0lAMTBRkLzY0PhHD5/0g5fHCuEG4jACisAkL8zzPHorSApfaBcVhbQg87+7S zIpErlb2eSYlLQ4/8mT1Qfeuxwy30cR1iF0q4klZca//ixAeQI4CkUgGrYTRbH9sTVIL KCxZpxJVm2pyLvGxcRL9EX2cS9dB66wKW0wnAB2FuI6+SOGlyV+UN+5oOEwn3Mq9dSOp aDf09E/aMjuAwkp/SCI1FThVstjDk4TWlpkagiGVhRkTA4OyAQIxTDHgpknqwlAoK7WE b1BQ== X-Gm-Message-State: AGi0Pubckb1qtzU+Lkrbgc7qhH3ChJwsYq9Tr18aBSHhZxpGHslyq5Ug 8PCML8BEvBQFk7hLkDm6/12/T0Ky7XkSsg== X-Google-Smtp-Source: APiQypLVOa4V7tlF7pfUBF58FrR/Sl2qubPAYYYFzCjd0uwI6EraKjScYRTjZStBvderiIuPOLopoQ== X-Received: by 2002:ad4:55c4:: with SMTP id bt4mr2568264qvb.225.1587129737683; Fri, 17 Apr 2020 06:22:17 -0700 (PDT) Received: from localhost.localdomain ([177.194.48.209]) by smtp.googlemail.com with ESMTPSA id s14sm14737571qts.70.2020.04.17.06.22.16 for (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Fri, 17 Apr 2020 06:22:17 -0700 (PDT) From: Adhemerval Zanella To: libc-alpha@sourceware.org Subject: [PATCH 03/10] linux: Add __readdir_unlocked Date: Fri, 17 Apr 2020 10:22:02 -0300 Message-Id: <20200417132209.22065-3-adhemerval.zanella@linaro.org> X-Mailer: git-send-email 2.17.1 In-Reply-To: <20200417132209.22065-1-adhemerval.zanella@linaro.org> References: <20200417132209.22065-1-adhemerval.zanella@linaro.org> X-Spam-Status: No, score=-25.6 required=5.0 tests=BAYES_00, DKIM_SIGNED, DKIM_VALID, DKIM_VALID_AU, DKIM_VALID_EF, GIT_PATCH_0, GIT_PATCH_1, GIT_PATCH_2, GIT_PATCH_3, RCVD_IN_DNSWL_NONE, 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-List-Received-Date: Fri, 17 Apr 2020 13:22:19 -0000 And use it on readdir_r implementation. Checked on i686-linux-gnu. --- include/dirent.h | 1 + sysdeps/unix/sysv/linux/readdir.c | 18 +++++-- sysdeps/unix/sysv/linux/readdir_r.c | 79 +++++++---------------------- 3 files changed, 31 insertions(+), 67 deletions(-) diff --git a/include/dirent.h b/include/dirent.h index fdf4c4a2f1..8325a19e5f 100644 --- a/include/dirent.h +++ b/include/dirent.h @@ -20,6 +20,7 @@ extern DIR *__opendirat (int dfd, const char *__name) attribute_hidden; extern DIR *__fdopendir (int __fd) attribute_hidden; extern int __closedir (DIR *__dirp) attribute_hidden; extern struct dirent *__readdir (DIR *__dirp) attribute_hidden; +extern struct dirent *__readdir_unlocked (DIR *__dirp) attribute_hidden; extern struct dirent64 *__readdir64 (DIR *__dirp); libc_hidden_proto (__readdir64) extern int __readdir_r (DIR *__dirp, struct dirent *__entry, diff --git a/sysdeps/unix/sysv/linux/readdir.c b/sysdeps/unix/sysv/linux/readdir.c index 2e03e66e69..ca2a8964e9 100644 --- a/sysdeps/unix/sysv/linux/readdir.c +++ b/sysdeps/unix/sysv/linux/readdir.c @@ -23,15 +23,11 @@ /* Read a directory entry from DIRP. */ struct dirent * -__readdir (DIR *dirp) +__readdir_unlocked (DIR *dirp) { struct dirent *dp; int saved_errno = errno; -#if IS_IN (libc) - __libc_lock_lock (dirp->lock); -#endif - do { size_t reclen; @@ -75,6 +71,18 @@ __readdir (DIR *dirp) /* Skip deleted files. */ } while (dp->d_ino == 0); + return dp; +} + +struct dirent * +__readdir (DIR *dirp) +{ + struct dirent *dp; + +#if IS_IN (libc) + __libc_lock_lock (dirp->lock); +#endif + dp = __readdir_unlocked (dirp); #if IS_IN (libc) __libc_lock_unlock (dirp->lock); #endif diff --git a/sysdeps/unix/sysv/linux/readdir_r.c b/sysdeps/unix/sysv/linux/readdir_r.c index 0069041394..a01d2845a6 100644 --- a/sysdeps/unix/sysv/linux/readdir_r.c +++ b/sysdeps/unix/sysv/linux/readdir_r.c @@ -25,89 +25,44 @@ __readdir_r (DIR *dirp, struct dirent *entry, struct dirent **result) { struct dirent *dp; size_t reclen; - const int saved_errno = errno; - int ret; __libc_lock_lock (dirp->lock); - do + while (1) { - if (dirp->offset >= dirp->size) - { - /* We've emptied out our buffer. Refill it. */ - - size_t maxread = dirp->allocation; - ssize_t bytes; - - maxread = dirp->allocation; - - bytes = __getdents (dirp->fd, dirp->data, maxread); - if (bytes <= 0) - { - /* On some systems getdents fails with ENOENT when the - open directory has been rmdir'd already. POSIX.1 - requires that we treat this condition like normal EOF. */ - if (bytes < 0 && errno == ENOENT) - { - bytes = 0; - __set_errno (saved_errno); - } - if (bytes < 0) - dirp->errcode = errno; - - dp = NULL; - break; - } - dirp->size = (size_t) bytes; - - /* Reset the offset into the buffer. */ - dirp->offset = 0; - } - - dp = (struct dirent *) &dirp->data[dirp->offset]; + dp = __readdir_unlocked (dirp); + if (dp == NULL) + break; reclen = dp->d_reclen; + if (reclen <= offsetof (struct dirent, d_name) + NAME_MAX + 1) + break; - dirp->offset += reclen; - - dirp->filepos = dp->d_off; - - if (reclen > offsetof (struct dirent, d_name) + NAME_MAX + 1) + /* The record is very long. It could still fit into the caller-supplied + buffer if we can skip padding at the end. */ + size_t namelen = _D_EXACT_NAMLEN (dp); + if (namelen <= NAME_MAX) { - /* The record is very long. It could still fit into the - caller-supplied buffer if we can skip padding at the - end. */ - size_t namelen = _D_EXACT_NAMLEN (dp); - if (namelen <= NAME_MAX) - reclen = offsetof (struct dirent, d_name) + namelen + 1; - else - { - /* The name is too long. Ignore this file. */ - dirp->errcode = ENAMETOOLONG; - dp->d_ino = 0; - continue; - } + reclen = offsetof (struct dirent, d_name) + namelen + 1; + break; } - /* Skip deleted and ignored files. */ + /* The name is too long. Ignore this file. */ + dirp->errcode = ENAMETOOLONG; + dp->d_ino = 0; } - while (dp->d_ino == 0); if (dp != NULL) { *result = memcpy (entry, dp, reclen); entry->d_reclen = reclen; - ret = 0; } else - { - *result = NULL; - ret = dirp->errcode; - } + *result = NULL; __libc_lock_unlock (dirp->lock); - return ret; + return dp != NULL ? 0 : dirp->errcode; } weak_alias (__readdir_r, readdir_r)