From patchwork Thu Jan 20 09:32:50 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Siddhesh Poyarekar X-Patchwork-Id: 50261 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 40A763857C7B for ; Thu, 20 Jan 2022 09:34:13 +0000 (GMT) DKIM-Filter: OpenDKIM Filter v2.11.0 sourceware.org 40A763857C7B DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=sourceware.org; s=default; t=1642671253; bh=kpjCAOJBee6gdyz2STCr6gn+yDVW1cwNjOobBN9gpV4=; h=To:Subject:Date:In-Reply-To:References:List-Id:List-Unsubscribe: List-Archive:List-Post:List-Help:List-Subscribe:From:Reply-To:Cc: From; b=w/xrr4MYoUTK1RIRDH5MrL+3N/HH73jj8UrBZuhSqOXC+XK/blrYzrQgs9V3ywhDd 0lOzbgBzv7RhtjvkfGGUGr99PyBKJAaprtSxRnVaHx+2TmhKGnbjBABHcMMZJzfG5k S+JfRBSsJ2JtJCfod4Y5eE+V1QKBSE8k0fahLhx4= X-Original-To: libc-alpha@sourceware.org Delivered-To: libc-alpha@sourceware.org Received: from dormouse.elm.relay.mailchannels.net (dormouse.elm.relay.mailchannels.net [23.83.212.50]) by sourceware.org (Postfix) with ESMTPS id 7CEA23857811 for ; Thu, 20 Jan 2022 09:33:15 +0000 (GMT) DMARC-Filter: OpenDMARC Filter v1.4.1 sourceware.org 7CEA23857811 X-Sender-Id: dreamhost|x-authsender|siddhesh@gotplt.org Received: from relay.mailchannels.net (localhost [127.0.0.1]) by relay.mailchannels.net (Postfix) with ESMTP id CB6E26218D7; Thu, 20 Jan 2022 09:33:11 +0000 (UTC) Received: from pdx1-sub0-mail-a307.dreamhost.com (unknown [127.0.0.6]) (Authenticated sender: dreamhost) by relay.mailchannels.net (Postfix) with ESMTPA id 1B39E62183F; Thu, 20 Jan 2022 09:33:11 +0000 (UTC) X-Sender-Id: dreamhost|x-authsender|siddhesh@gotplt.org Received: from pdx1-sub0-mail-a307.dreamhost.com (pop.dreamhost.com [64.90.62.162]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384) by 100.126.0.19 (trex/6.4.3); Thu, 20 Jan 2022 09:33:11 +0000 X-MC-Relay: Neutral X-MailChannels-SenderId: dreamhost|x-authsender|siddhesh@gotplt.org X-MailChannels-Auth-Id: dreamhost X-Decisive-White: 706938bb2e76bc13_1642671191727_4213874154 X-MC-Loop-Signature: 1642671191727:3640613859 X-MC-Ingress-Time: 1642671191726 Received: from rhbox.redhat.com (unknown [1.186.224.209]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (4096 bits) server-digest SHA256) (No client certificate requested) (Authenticated sender: siddhesh@gotplt.org) by pdx1-sub0-mail-a307.dreamhost.com (Postfix) with ESMTPSA id 4JfckV4prDz2S; Thu, 20 Jan 2022 01:33:06 -0800 (PST) To: libc-alpha@sourceware.org Subject: [PATCH v3 1/3] support: Add helpers to create paths longer than PATH_MAX Date: Thu, 20 Jan 2022 15:02:50 +0530 Message-Id: <20220120093252.1911498-2-siddhesh@sourceware.org> X-Mailer: git-send-email 2.34.1 In-Reply-To: <20220120093252.1911498-1-siddhesh@sourceware.org> References: <20220119082147.3352868-1-siddhesh@sourceware.org> <20220120093252.1911498-1-siddhesh@sourceware.org> MIME-Version: 1.0 X-Spam-Status: No, score=-3493.5 required=5.0 tests=BAYES_00, GIT_PATCH_0, JMQ_SPF_NEUTRAL, KAM_DMARC_NONE, KAM_DMARC_STATUS, RCVD_IN_BARRACUDACENTRAL, RCVD_IN_DNSWL_NONE, RCVD_IN_MSPIKE_H3, RCVD_IN_MSPIKE_WL, SPF_HELO_NONE, SPF_NEUTRAL, TXREP autolearn=ham autolearn_force=no version=3.4.4 X-Spam-Checker-Version: SpamAssassin 3.4.4 (2020-01-24) 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: Siddhesh Poyarekar via Libc-alpha From: Siddhesh Poyarekar Reply-To: Siddhesh Poyarekar Cc: fweimer@redhat.com Errors-To: libc-alpha-bounces+patchwork=sourceware.org@sourceware.org Sender: "Libc-alpha" Add new helpers support_create_and_chdir_toolong_temp_directory and support_chdir_toolong_temp_directory to create and descend into directory trees longer than PATH_MAX. Signed-off-by: Siddhesh Poyarekar Reviewed-by: Adhemerval Zanella --- support/temp_file.c | 159 +++++++++++++++++++++++++++++++++++++++++--- support/temp_file.h | 9 +++ 2 files changed, 159 insertions(+), 9 deletions(-) diff --git a/support/temp_file.c b/support/temp_file.c index e7bb8aadb9..e41128c2d4 100644 --- a/support/temp_file.c +++ b/support/temp_file.c @@ -1,5 +1,6 @@ /* Temporary file handling for tests. Copyright (C) 1998-2022 Free Software Foundation, Inc. + Copyright The GNU Tools Authors. This file is part of the GNU C Library. The GNU C Library is free software; you can redistribute it and/or @@ -20,15 +21,17 @@ some 32-bit platforms. */ #define _FILE_OFFSET_BITS 64 +#include #include #include #include +#include #include #include #include #include -#include +#include /* List of temporary files. */ static struct temp_name_list @@ -36,14 +39,20 @@ static struct temp_name_list struct temp_name_list *next; char *name; pid_t owner; + bool toolong; } *temp_name_list; /* Location of the temporary files. Set by the test skeleton via support_set_test_dir. The string is not be freed. */ static const char *test_dir = _PATH_TMP; -void -add_temp_file (const char *name) +/* Name of subdirectories in a too long temporary directory tree. */ +static char toolong_subdir[NAME_MAX + 1]; +static bool toolong_initialized; +static size_t toolong_path_max; + +static void +add_temp_file_internal (const char *name, bool toolong) { struct temp_name_list *newp = (struct temp_name_list *) xcalloc (sizeof (*newp), 1); @@ -53,12 +62,19 @@ add_temp_file (const char *name) newp->name = newname; newp->next = temp_name_list; newp->owner = getpid (); + newp->toolong = toolong; temp_name_list = newp; } else free (newp); } +void +add_temp_file (const char *name) +{ + add_temp_file_internal (name, false); +} + int create_temp_file_in_dir (const char *base, const char *dir, char **filename) { @@ -90,8 +106,8 @@ create_temp_file (const char *base, char **filename) return create_temp_file_in_dir (base, test_dir, filename); } -char * -support_create_temp_directory (const char *base) +static char * +create_temp_directory_internal (const char *base, bool toolong) { char *path = xasprintf ("%s/%sXXXXXX", test_dir, base); if (mkdtemp (path) == NULL) @@ -99,16 +115,132 @@ support_create_temp_directory (const char *base) printf ("error: mkdtemp (\"%s\"): %m", path); exit (1); } - add_temp_file (path); + add_temp_file_internal (path, toolong); return path; } -/* Helper functions called by the test skeleton follow. */ +char * +support_create_temp_directory (const char *base) +{ + return create_temp_directory_internal (base, false); +} + +static void +ensure_toolong_initialized (void) +{ + if (!toolong_initialized) + FAIL_EXIT1 ("uninitialized toolong directory tree\n"); +} + +static void +initialize_toolong (const char *base) +{ + long name_max = pathconf (base, _PC_NAME_MAX); + name_max = (name_max < 0 ? 64 + : (name_max < sizeof (toolong_subdir) ? name_max + : sizeof (toolong_subdir) - 1)); + + long path_max = pathconf (base, _PC_PATH_MAX); + path_max = (path_max < 0 ? 1024 + : path_max <= PTRDIFF_MAX ? path_max : PTRDIFF_MAX); + + /* Sanity check to ensure that the test does not create temporary directories + in different filesystems because this API doesn't support it. */ + if (toolong_initialized) + { + if (name_max != strlen (toolong_subdir)) + FAIL_UNSUPPORTED ("name_max: Temporary directories in different" + " filesystems not supported yet\n"); + if (path_max != toolong_path_max) + FAIL_UNSUPPORTED ("path_max: Temporary directories in different" + " filesystems not supported yet\n"); + return; + } + + toolong_path_max = path_max; + + size_t len = name_max; + memset (toolong_subdir, 'X', len); + toolong_initialized = true; +} + +char * +support_create_and_chdir_toolong_temp_directory (const char *basename) +{ + char *base = create_temp_directory_internal (basename, true); + xchdir (base); + + initialize_toolong (base); + + size_t sz = strlen (toolong_subdir); + + /* Create directories and descend into them so that the final path is larger + than PATH_MAX. */ + for (size_t i = 0; i <= toolong_path_max / sz; i++) + { + int ret = mkdir (toolong_subdir, S_IRWXU); + if (ret != 0 && errno == ENAMETOOLONG) + FAIL_UNSUPPORTED ("Filesystem does not support creating too long " + "directory trees\n"); + else if (ret != 0) + FAIL_EXIT1 ("Failed to create directory tree: %m\n"); + xchdir (toolong_subdir); + } + return base; +} void -support_set_test_dir (const char *path) +support_chdir_toolong_temp_directory (const char *base) { - test_dir = path; + ensure_toolong_initialized (); + + xchdir (base); + + size_t sz = strlen (toolong_subdir); + for (size_t i = 0; i <= toolong_path_max / sz; i++) + xchdir (toolong_subdir); +} + +/* Helper functions called by the test skeleton follow. */ + +static void +remove_toolong_subdirs (const char *base) +{ + ensure_toolong_initialized (); + + if (chdir (base) != 0) + { + printf ("warning: toolong cleanup base failed: chdir (\"%s\"): %m\n", + base); + return; + } + + /* Descend. */ + int levels = 0; + size_t sz = strlen (toolong_subdir); + for (levels = 0; levels <= toolong_path_max / sz; levels++) + if (chdir (toolong_subdir) != 0) + { + printf ("warning: toolong cleanup failed: chdir (\"%s\"): %m\n", + toolong_subdir); + break; + } + + /* Ascend and remove. */ + while (--levels >= 0) + { + if (chdir ("..") != 0) + { + printf ("warning: toolong cleanup failed: chdir (\"..\"): %m\n"); + return; + } + if (remove (toolong_subdir) != 0) + { + printf ("warning: could not remove subdirectory: %s: %m\n", + toolong_subdir); + return; + } + } } void @@ -123,6 +255,9 @@ support_delete_temp_files (void) around, to prevent PID reuse.) */ if (temp_name_list->owner == pid) { + if (temp_name_list->toolong) + remove_toolong_subdirs (temp_name_list->name); + if (remove (temp_name_list->name) != 0) printf ("warning: could not remove temporary file: %s: %m\n", temp_name_list->name); @@ -147,3 +282,9 @@ support_print_temp_files (FILE *f) fprintf (f, ")\n"); } } + +void +support_set_test_dir (const char *path) +{ + test_dir = path; +} diff --git a/support/temp_file.h b/support/temp_file.h index 50a443abe4..8459ddda72 100644 --- a/support/temp_file.h +++ b/support/temp_file.h @@ -44,6 +44,15 @@ int create_temp_file_in_dir (const char *base, const char *dir, returns. The caller should free this string. */ char *support_create_temp_directory (const char *base); +/* Create a temporary directory tree that is longer than PATH_MAX and schedule + it for deletion. BASENAME is used as a prefix for the unique directory + name, which the function returns. The caller should free this string. */ +char *support_create_and_chdir_toolong_temp_directory (const char *basename); + +/* Change into the innermost directory of the directory tree BASE, which was + created using support_create_and_chdir_toolong_temp_directory. */ +void support_chdir_toolong_temp_directory (const char *base); + __END_DECLS #endif /* SUPPORT_TEMP_FILE_H */