From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.2 (2018-09-13) on dcvr.yhbt.net X-Spam-Level: X-Spam-ASN: AS3215 2.6.0.0/16 X-Spam-Status: No, score=-3.6 required=3.0 tests=AWL,BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,RCVD_IN_DNSWL_HI, SPF_HELO_NONE,SPF_PASS shortcircuit=no autolearn=ham autolearn_force=no version=3.4.2 Received: from out1.vger.email (out1.vger.email [IPv6:2620:137:e000::1:20]) by dcvr.yhbt.net (Postfix) with ESMTP id 395541F51E for ; Fri, 14 Oct 2022 21:47:01 +0000 (UTC) Authentication-Results: dcvr.yhbt.net; dkim=pass (2048-bit key; unprotected) header.d=gmail.com header.i=@gmail.com header.b="qdHCeLiS"; dkim-atps=neutral Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229995AbiJNVqp (ORCPT ); Fri, 14 Oct 2022 17:46:45 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:39822 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229744AbiJNVqg (ORCPT ); Fri, 14 Oct 2022 17:46:36 -0400 Received: from mail-wm1-x332.google.com (mail-wm1-x332.google.com [IPv6:2a00:1450:4864:20::332]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 439CC4B4B6 for ; Fri, 14 Oct 2022 14:45:58 -0700 (PDT) Received: by mail-wm1-x332.google.com with SMTP id v130-20020a1cac88000000b003bcde03bd44so6540989wme.5 for ; Fri, 14 Oct 2022 14:45:58 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20210112; h=cc:to:mime-version:content-transfer-encoding:fcc:subject:date:from :references:in-reply-to:message-id:from:to:cc:subject:date :message-id:reply-to; bh=JzsaAR0X8JQprc/ENUUg7TQxj4tsxrHAeMaKjdaTLuE=; b=qdHCeLiSUquabkOHe/wd+7avFaSo1xJuD//r72lAozdLtCBmDfH7lXCunn8IB4Fpmk fDdWZ/DUgObXIrMLqN0Doo8Lf/jJhfREnPIAzZzyEqQYI0WdIxuLS0EkIXtBtukKypES 2U01RXLT5feaIZSfumVBtdRk4rz4cpIDPXng9T9f/DD13oc9VHAYSce/fLU5DQu0ZbTr ZXczla/JiRtFyNWKOMprCcsN41a+e83Hv1pQK/JvAd/+Jq9M+o8X+7meKfUnklaWDmHY grM4x40v5h2ttOCnSWtqkoTHMbMxqFMuBBrIzl4FPs12CM271/42bV4bMuwGYB2ZNLd2 6l4A== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=cc:to:mime-version:content-transfer-encoding:fcc:subject:date:from :references:in-reply-to:message-id:x-gm-message-state:from:to:cc :subject:date:message-id:reply-to; bh=JzsaAR0X8JQprc/ENUUg7TQxj4tsxrHAeMaKjdaTLuE=; b=QyJpTtp6DYTJiB6AxLxtLNKZVbC87rZ3cYxIY/xuUj+eOYAOuAkqeGZ/drECmOb7fq T7kzka4zkQ39+EfD+BLKznVBqXhFd8NiqBmaqL+E01Jrz+37JyhzKoVul79w/Mig2Qpj rZG1BLr6dnfEf1bn8hxYNqQOtUfXz7bXe1kv/cXC1Xaf9aKZBkRjt7ZTURjNPr8RPDaW QymzOrfTa8KCEZpofoodUDbkW74knA4v7G6OM2KnCcleUFDWMqRkI1Sno6P0C6YEuv/u +4k/YmMyPlyMJxekkPBMEWFGGdG9klfB0f3nCqzN95gAIA/L5W/sCRXihi5Bo6apglu/ ljxA== X-Gm-Message-State: ACrzQf2m94+ZCWR+oUxneU3a12zL9dqCFNuaByIEmcJzj6kdLn9iIE0+ mXUHUK9hhyP0+Zz7w198WJJFFdMtABk= X-Google-Smtp-Source: AMsMyM675EajXu+oaZKhpYJxOuPYCkY0O30MfZjm2gx+1hbGr6ETigY+8/MmFeHTmYiPR/Y3cLqsYA== X-Received: by 2002:a05:600c:3b21:b0:3c6:172:9c5a with SMTP id m33-20020a05600c3b2100b003c601729c5amr5091967wms.129.1665783956077; Fri, 14 Oct 2022 14:45:56 -0700 (PDT) Received: from [127.0.0.1] ([13.74.141.28]) by smtp.gmail.com with ESMTPSA id g8-20020a7bc4c8000000b003c0d504a92csm7728903wmk.22.2022.10.14.14.45.54 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Fri, 14 Oct 2022 14:45:55 -0700 (PDT) Message-Id: <7d7ef78728f890db68166b3b5b6b7dd33f20e62c.1665783945.git.gitgitgadget@gmail.com> In-Reply-To: References: From: "Eric DeCosta via GitGitGadget" Date: Fri, 14 Oct 2022 21:45:40 +0000 Subject: [PATCH v2 08/12] fsmonitor: determine if filesystem is local or remote Fcc: Sent Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit MIME-Version: 1.0 To: git@vger.kernel.org Cc: Eric Sunshine , =?UTF-8?Q?=C3=86var_Arnfj=C3=B6r=C3=B0?= Bjarmason , Eric DeCosta , Eric DeCosta Precedence: bulk List-ID: X-Mailing-List: git@vger.kernel.org From: Eric DeCosta Compare the given path to the mounted filesystems. Find the mount that is the longest prefix of the path (if any) and determine if that mount is on a local or remote filesystem. Signed-off-by: Eric DeCosta --- compat/fsmonitor/fsm-path-utils-linux.c | 169 ++++++++++++++++++++++++ 1 file changed, 169 insertions(+) create mode 100644 compat/fsmonitor/fsm-path-utils-linux.c diff --git a/compat/fsmonitor/fsm-path-utils-linux.c b/compat/fsmonitor/fsm-path-utils-linux.c new file mode 100644 index 00000000000..039f044b670 --- /dev/null +++ b/compat/fsmonitor/fsm-path-utils-linux.c @@ -0,0 +1,169 @@ +#include "fsmonitor.h" +#include "fsmonitor-path-utils.h" +#include +#include +#include +#include + +/* + * https://github.com/coreutils/gnulib/blob/master/lib/mountlist.c + */ +#ifndef ME_REMOTE +/* A file system is "remote" if its Fs_name contains a ':' + or if (it is of type (smbfs or cifs) and its Fs_name starts with '//') + or if it is of any other of the listed types + or Fs_name is equal to "-hosts" (used by autofs to mount remote fs). + "VM" file systems like prl_fs or vboxsf are not considered remote here. */ +# define ME_REMOTE(Fs_name, Fs_type) \ + (strchr (Fs_name, ':') != NULL \ + || ((Fs_name)[0] == '/' \ + && (Fs_name)[1] == '/' \ + && (strcmp (Fs_type, "smbfs") == 0 \ + || strcmp (Fs_type, "smb3") == 0 \ + || strcmp (Fs_type, "cifs") == 0)) \ + || strcmp (Fs_type, "acfs") == 0 \ + || strcmp (Fs_type, "afs") == 0 \ + || strcmp (Fs_type, "coda") == 0 \ + || strcmp (Fs_type, "auristorfs") == 0 \ + || strcmp (Fs_type, "fhgfs") == 0 \ + || strcmp (Fs_type, "gpfs") == 0 \ + || strcmp (Fs_type, "ibrix") == 0 \ + || strcmp (Fs_type, "ocfs2") == 0 \ + || strcmp (Fs_type, "vxfs") == 0 \ + || strcmp ("-hosts", Fs_name) == 0) +#endif + +static int find_mount(const char *path, const struct statvfs *fs, + struct mntent *ent) +{ + const char *const mounts = "/proc/mounts"; + const char *rp = real_pathdup(path, 1); + struct mntent *ment = NULL; + struct statvfs mntfs; + FILE *fp; + int found = 0; + int dlen, plen, flen = 0; + + ent->mnt_fsname = NULL; + ent->mnt_dir = NULL; + ent->mnt_type = NULL; + + fp = setmntent(mounts, "r"); + if (!fp) { + error_errno(_("setmntent('%s') failed"), mounts); + return -1; + } + + plen = strlen(rp); + + /* read all the mount information and compare to path */ + while ((ment = getmntent(fp)) != NULL) { + if (statvfs(ment->mnt_dir, &mntfs)) { + switch (errno) { + case EPERM: + case ESRCH: + case EACCES: + continue; + default: + error_errno(_("statvfs('%s') failed"), ment->mnt_dir); + endmntent(fp); + return -1; + } + } + + /* is mount on the same filesystem and is a prefix of the path */ + if ((fs->f_fsid == mntfs.f_fsid) && + !strncmp(ment->mnt_dir, rp, strlen(ment->mnt_dir))) { + dlen = strlen(ment->mnt_dir); + if (dlen > plen) + continue; + /* + * root is always a potential match; otherwise look for + * directory prefix + */ + if ((dlen == 1 && ment->mnt_dir[0] == '/') || + (dlen > flen && (!rp[dlen] || rp[dlen] == '/'))) { + flen = dlen; + /* + * https://man7.org/linux/man-pages/man3/getmntent.3.html + * + * The pointer points to a static area of memory which is + * overwritten by subsequent calls to getmntent(). + */ + found = 1; + free(ent->mnt_fsname); + free(ent->mnt_dir); + free(ent->mnt_type); + ent->mnt_fsname = xstrdup(ment->mnt_fsname); + ent->mnt_dir = xstrdup(ment->mnt_dir); + ent->mnt_type = xstrdup(ment->mnt_type); + } + } + } + endmntent(fp); + + if (!found) + return -1; + + return 0; +} + +int fsmonitor__get_fs_info(const char *path, struct fs_info *fs_info) +{ + struct mntent ment; + struct statvfs fs; + + if (statvfs(path, &fs)) + return error_errno(_("statvfs('%s') failed"), path); + + + if (find_mount(path, &fs, &ment) < 0) { + free(ment.mnt_fsname); + free(ment.mnt_dir); + free(ment.mnt_type); + return -1; + } + + trace_printf_key(&trace_fsmonitor, + "statvfs('%s') [flags 0x%08lx] '%s' '%s'", + path, fs.f_flag, ment.mnt_type, ment.mnt_fsname); + + fs_info->is_remote = ME_REMOTE(ment.mnt_fsname, ment.mnt_type); + fs_info->typename = ment.mnt_fsname; + free(ment.mnt_dir); + free(ment.mnt_type); + + trace_printf_key(&trace_fsmonitor, + "'%s' is_remote: %d", + path, fs_info->is_remote); + return 0; +} + +int fsmonitor__is_fs_remote(const char *path) +{ + struct fs_info fs; + + if (fsmonitor__get_fs_info(path, &fs)) + return -1; + + free(fs.typename); + + return fs.is_remote; +} + +/* + * No-op for now. + */ +int fsmonitor__get_alias(const char *path, struct alias_info *info) +{ + return 0; +} + +/* + * No-op for now. + */ +char *fsmonitor__resolve_alias(const char *path, + const struct alias_info *info) +{ + return NULL; +} -- gitgitgadget