From patchwork Tue Jan 18 09:07:26 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Siddhesh Poyarekar X-Patchwork-Id: 1581151 Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@bilbo.ozlabs.org Authentication-Results: bilbo.ozlabs.org; dkim=pass (1024-bit key; secure) header.d=sourceware.org header.i=@sourceware.org header.a=rsa-sha256 header.s=default header.b=U6nOfYZs; dkim-atps=neutral Authentication-Results: ozlabs.org; spf=pass (sender SPF authorized) smtp.mailfrom=sourceware.org (client-ip=8.43.85.97; helo=sourceware.org; envelope-from=libc-alpha-bounces+incoming=patchwork.ozlabs.org@sourceware.org; receiver=) Received: from sourceware.org (server2.sourceware.org [8.43.85.97]) (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) by bilbo.ozlabs.org (Postfix) with ESMTPS id 4JdNHF290sz9sRR for ; Tue, 18 Jan 2022 20:08:41 +1100 (AEDT) Received: from server2.sourceware.org (localhost [IPv6:::1]) by sourceware.org (Postfix) with ESMTP id 62E6E3858019 for ; Tue, 18 Jan 2022 09:08:38 +0000 (GMT) DKIM-Filter: OpenDKIM Filter v2.11.0 sourceware.org 62E6E3858019 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=sourceware.org; s=default; t=1642496918; bh=2kzi1RIn+xpdYpO7AwXP2Yt9qh8YGWSZ/MhsWbZgjnU=; 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=U6nOfYZsvqJo1REC+4WFRITQmx2mp9qqcuL1VrOeRj5T45AoYzSrblNaeSa08caY+ gJUjwE5yh3jyIjW97O0QiJeol26Uf7Zj0ZNvQ4VrDkSv1H1L0S2ZciyZrrj2k4arPU nJCCeYo9lSOkVjRfTTnTT4SnMcLJb9PrAOF+kGBk= X-Original-To: libc-alpha@sourceware.org Delivered-To: libc-alpha@sourceware.org Received: from bee.birch.relay.mailchannels.net (bee.birch.relay.mailchannels.net [23.83.209.14]) by sourceware.org (Postfix) with ESMTPS id A17D43858022 for ; Tue, 18 Jan 2022 09:07:44 +0000 (GMT) DMARC-Filter: OpenDMARC Filter v1.4.1 sourceware.org A17D43858022 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 D05376C0EF5; Tue, 18 Jan 2022 09:07:41 +0000 (UTC) Received: from pdx1-sub0-mail-a306.dreamhost.com (unknown [127.0.0.6]) (Authenticated sender: dreamhost) by relay.mailchannels.net (Postfix) with ESMTPA id 5E7426C05C2; Tue, 18 Jan 2022 09:07:41 +0000 (UTC) X-Sender-Id: dreamhost|x-authsender|siddhesh@gotplt.org Received: from pdx1-sub0-mail-a306.dreamhost.com (pop.dreamhost.com [64.90.62.162]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384) by 100.114.70.224 (trex/6.4.3); Tue, 18 Jan 2022 09:07:41 +0000 X-MC-Relay: Neutral X-MailChannels-SenderId: dreamhost|x-authsender|siddhesh@gotplt.org X-MailChannels-Auth-Id: dreamhost X-Callous-Hook: 60fa92af55e13567_1642496861653_3679390095 X-MC-Loop-Signature: 1642496861653:2870152179 X-MC-Ingress-Time: 1642496861652 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-a306.dreamhost.com (Postfix) with ESMTPSA id 4JdNG31j3fz1M; Tue, 18 Jan 2022 01:07:38 -0800 (PST) To: libc-alpha@sourceware.org Subject: [PATCH 1/3] support: Add helpers to create paths longer than PATH_MAX Date: Tue, 18 Jan 2022 14:37:26 +0530 Message-Id: <20220118090728.1825487-2-siddhesh@sourceware.org> X-Mailer: git-send-email 2.34.1 In-Reply-To: <20220118090728.1825487-1-siddhesh@sourceware.org> References: <20220118090728.1825487-1-siddhesh@sourceware.org> MIME-Version: 1.0 X-Spam-Status: No, score=-3493.6 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+incoming=patchwork.ozlabs.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 --- support/temp_file.c | 157 +++++++++++++++++++++++++++++++++++++++++--- support/temp_file.h | 11 ++++ 2 files changed, 160 insertions(+), 8 deletions(-) diff --git a/support/temp_file.c b/support/temp_file.c index e7bb8aadb9..c3e83912ac 100644 --- a/support/temp_file.c +++ b/support/temp_file.c @@ -36,14 +36,31 @@ 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]; + +/* Return the maximum size of path on the target. */ +static inline size_t +get_path_max (void) +{ +#ifdef PATH_MAX + return PATH_MAX; +#else + size_t path_max = pathconf ("/", _PC_PATH_MAX); + return (path_max < 0 ? 1024 + : path_max <= PTRDIFF_MAX ? path_max : PTRDIFF_MAX); +#endif +} + +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 +70,19 @@ 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 +114,8 @@ 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 +123,124 @@ 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_subdir_initialized (void) +{ + for (size_t i = 0; i < NAME_MAX; i++) + if (toolong_subdir[i] != 'X') + { + printf ("uninitialized toolong directory tree\n"); + exit (1); + } +} + +char * +support_create_and_chdir_toolong_temp_directory (const char *basename) +{ + size_t path_max = get_path_max (); + + char *base = create_temp_directory_internal (basename, true); + + if (chdir (base) != 0) + { + printf ("error creating toolong base: chdir (\"%s\"): %m", base); + exit (1); + } + + memset (toolong_subdir, 'X', sizeof (toolong_subdir) - 1); + toolong_subdir[NAME_MAX] = '\0'; + + /* Create directories and descend into them so that the final path is larger + than PATH_MAX. */ + for (size_t i = 0; i <= path_max / sizeof (toolong_subdir); i++) + { + if (mkdir (toolong_subdir, S_IRWXU) != 0) + { + printf ("error creating toolong subdir: mkdir (\"%s\"): %m", + toolong_subdir); + exit (1); + } + if (chdir (toolong_subdir) != 0) + { + printf ("error creating toolong subdir: chdir (\"%s\"): %m", + toolong_subdir); + exit (1); + } + } + return base; +} void -support_set_test_dir (const char *path) +support_chdir_toolong_temp_directory (const char *base) { - test_dir = path; + size_t path_max = get_path_max (); + ensure_toolong_subdir_initialized (); + + if (chdir (base) != 0) + { + printf ("error: chdir (\"%s\"): %m", base); + exit (1); + } + + for (size_t i = 0; i <= path_max / sizeof (toolong_subdir); i++) + if (chdir (toolong_subdir) != 0) + { + printf ("error subdir: chdir (\"%s\"): %m", toolong_subdir); + exit (1); + } +} + +/* Helper functions called by the test skeleton follow. */ + +static void +remove_toolong_subdirs (const char *base) +{ + size_t path_max = get_path_max (); + + ensure_toolong_subdir_initialized (); + + if (chdir (base) != 0) + { + printf ("warning: toolong cleanup base failed: chdir (\"%s\"): %m\n", + base); + return; + } + + /* Descend. */ + int levels = 0; + for (levels = 0; levels <= path_max / sizeof (toolong_subdir); levels++) + if (chdir (toolong_subdir) != 0) + { + printf ("warning: toolong cleanup failed: chdir (\"%s\"): %m\n", + toolong_subdir); + return; + } + + /* 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..de01fbbceb 100644 --- a/support/temp_file.h +++ b/support/temp_file.h @@ -19,6 +19,8 @@ #ifndef SUPPORT_TEMP_FILE_H #define SUPPORT_TEMP_FILE_H +#include +#include #include __BEGIN_DECLS @@ -44,6 +46,15 @@ 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 */