From patchwork Tue Nov 9 11:40:19 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Florian Weimer X-Patchwork-Id: 47274 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 814443858022 for ; Tue, 9 Nov 2021 11:41:30 +0000 (GMT) DKIM-Filter: OpenDKIM Filter v2.11.0 sourceware.org 814443858022 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=sourceware.org; s=default; t=1636458090; bh=IprwbjL4Fp9rNIQjoIS2kprUfd1Ko/ORlcb+72Qp6DQ=; h=To:Subject:Date:List-Id:List-Unsubscribe:List-Archive:List-Post: List-Help:List-Subscribe:From:Reply-To:From; b=Sd+d8xY7rDZBnj7z2BO/W47v21LdXsw2qgF1KMOhBNJID6nKo0pwiUkfYHBB0sLWC LoatEWdrsLUgQWV7m094NS1nruuUnaAZre7/Wr2762NTiD2c4RrUBqtUBgUkxzOOhp Qw7qG7evgDo+BQD8HMm3JiBgrt9XbJqTV+trqHZk= X-Original-To: libc-alpha@sourceware.org Delivered-To: libc-alpha@sourceware.org Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [170.10.133.124]) by sourceware.org (Postfix) with ESMTPS id E29D83858C2C for ; Tue, 9 Nov 2021 11:40:25 +0000 (GMT) DMARC-Filter: OpenDMARC Filter v1.4.1 sourceware.org E29D83858C2C Received: from mimecast-mx01.redhat.com (mimecast-mx01.redhat.com [209.132.183.4]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-332-kipGXvdTMeOJVlH_UlmNmQ-1; Tue, 09 Nov 2021 06:40:23 -0500 X-MC-Unique: kipGXvdTMeOJVlH_UlmNmQ-1 Received: from smtp.corp.redhat.com (int-mx04.intmail.prod.int.phx2.redhat.com [10.5.11.14]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id A62469F92A for ; Tue, 9 Nov 2021 11:40:22 +0000 (UTC) Received: from oldenburg.str.redhat.com (unknown [10.39.192.82]) by smtp.corp.redhat.com (Postfix) with ESMTPS id CC6645DEFA for ; Tue, 9 Nov 2021 11:40:21 +0000 (UTC) To: libc-alpha@sourceware.org Subject: [PATCH] stdio: Implement %#m for vfprintf and related functions Date: Tue, 09 Nov 2021 12:40:19 +0100 Message-ID: <87h7cld0bg.fsf@oldenburg.str.redhat.com> User-Agent: Gnus/5.13 (Gnus v5.13) Emacs/27.2 (gnu/linux) MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.79 on 10.5.11.14 X-Mimecast-Spam-Score: 0 X-Mimecast-Originator: redhat.com X-Spam-Status: No, score=-12.7 required=5.0 tests=BAYES_00, DKIMWL_WL_HIGH, DKIM_SIGNED, DKIM_VALID, DKIM_VALID_AU, DKIM_VALID_EF, GIT_PATCH_0, KAM_SHORT, RCVD_IN_DNSWL_LOW, RCVD_IN_MSPIKE_H2, SPF_HELO_NONE, SPF_NONE, 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: Florian Weimer via Libc-alpha From: Florian Weimer Reply-To: Florian Weimer Errors-To: libc-alpha-bounces+patchwork=sourceware.org@sourceware.org Sender: "Libc-alpha" %#m prints errno as an error constant if one is available, or a decimal number as a fallback. This intends to address the gap that strerrorname_np does not work well with printf for unknown error codes due to its NULL return values in those cases. Tested on i686-linux-gnu and x86_64-linux-gnu. --- NEWS | 3 ++ manual/stdio.texi | 8 +++- stdio-common/Makefile | 4 +- stdio-common/tst-sprintf-errno.c | 93 ++++++++++++++++++++++++++++++++++++++++ stdio-common/vfprintf-internal.c | 25 ++++++++--- 5 files changed, 125 insertions(+), 8 deletions(-) diff --git a/NEWS b/NEWS index 82b7016aef..bc7bb788df 100644 --- a/NEWS +++ b/NEWS @@ -64,6 +64,9 @@ Major new features: to be used by compilers for optimizing usage of 'memcmp' when its return value is only used for its boolean status. +* The printf family of functions now handles the flagged %#m conversion + specifier, printing errno as an error constant (similar to strerrorname_np). + Deprecated and removed features, and other changes affecting compatibility: * The r_version update in the debugger interface makes the glibc binary diff --git a/manual/stdio.texi b/manual/stdio.texi index 1d235be68d..5ec770220b 100644 --- a/manual/stdio.texi +++ b/manual/stdio.texi @@ -1938,6 +1938,9 @@ which can be parsed by the @code{strtoul} function (@pxref{Parsing of Integers}) and @code{scanf} with the @samp{%i} conversion (@pxref{Numeric Input Conversions}). +For the @samp{%m} conversion, print an error constant or decimal error +number, instead of a (possibly translated) error message. + @item @samp{'} Separate the digits into groups as specified by the locale specified for the @code{LC_NUMERIC} category; @pxref{General Numeric}. This flag is a @@ -2259,8 +2262,9 @@ is equivalent to: fprintf (stderr, "can't open `%s': %s\n", filename, strerror (errno)); @end smallexample -@noindent -The @samp{%m} conversion is a @glibcadj{} extension. +The @samp{%m} conversion can be used with the @samp{#} flag to print an +error constant, as provided by @code{strerrorname_np}. Both @samp{%m} +and @samp{%#m} are @glibcadj{} extensions. The @samp{%p} conversion prints a pointer value. The corresponding argument must be of type @code{void *}. In practice, you can use any diff --git a/stdio-common/Makefile b/stdio-common/Makefile index 803f16dae0..d7bdf5a17e 100644 --- a/stdio-common/Makefile +++ b/stdio-common/Makefile @@ -70,7 +70,9 @@ tests := tstscanf test_rdwr test-popen tstgetln test-fseek \ tst-vfprintf-width-prec-alloc \ tst-printf-fp-free \ tst-printf-fp-leak \ - test-strerr + test-strerr \ + tst-sprintf-errno \ + # tests test-srcs = tst-unbputc tst-printf tst-printfsz-islongdouble diff --git a/stdio-common/tst-sprintf-errno.c b/stdio-common/tst-sprintf-errno.c new file mode 100644 index 0000000000..7622fdbc48 --- /dev/null +++ b/stdio-common/tst-sprintf-errno.c @@ -0,0 +1,93 @@ +/* Test the %m, %#m printf specifiers via asprintf. + Copyright (C) 2021 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 + . */ + +#include +#include +#include +#include +#include + +/* GCC does not yet know about the %#m specifier. */ +DIAG_PUSH_NEEDS_COMMENT; +DIAG_IGNORE_NEEDS_COMMENT (11, "-Wformat="); + +static int +do_test (void) +{ + char buf[64]; + + errno = EINVAL; + TEST_COMPARE (sprintf (buf, "%m"), 16); + TEST_COMPARE_STRING (buf, "Invalid argument"); + + errno = EINVAL; + TEST_COMPARE (sprintf (buf, "%#m"), 6); + TEST_COMPARE_STRING (buf, "EINVAL"); + + errno = 0; + TEST_COMPARE (sprintf (buf, "%m"), 7); + TEST_COMPARE_STRING (buf, "Success"); + + errno = 0; + TEST_COMPARE (sprintf (buf, "%#m"), 1); + TEST_COMPARE_STRING (buf, "0"); + + errno = -1; + TEST_COMPARE (sprintf (buf, "%m"), 16); + TEST_COMPARE_STRING (buf, "Unknown error -1"); + + errno = -1; + TEST_COMPARE (sprintf (buf, "%#m"), 2); + TEST_COMPARE_STRING (buf, "-1"); + + errno = 1002003; + TEST_COMPARE (sprintf (buf, "%m"), 21); + TEST_COMPARE_STRING (buf, "Unknown error 1002003"); + + errno = 1002003; + TEST_COMPARE (sprintf (buf, "%#m"), 7); + TEST_COMPARE_STRING (buf, "1002003"); + + errno = EINVAL; + TEST_COMPARE (sprintf (buf, "%20m"), 20); + TEST_COMPARE_STRING (buf, " Invalid argument"); + + errno = EINVAL; + TEST_COMPARE (sprintf (buf, "%#20m"), 20); + TEST_COMPARE_STRING (buf, " EINVAL"); + + errno = EINVAL; + TEST_COMPARE (sprintf (buf, "%-20m"), 20); + TEST_COMPARE_STRING (buf, "Invalid argument "); + + errno = EINVAL; + TEST_COMPARE (sprintf (buf, "%-#20m"), 20); + TEST_COMPARE_STRING (buf, "EINVAL "); + + errno = 0; + TEST_COMPARE (sprintf (buf, "%-20m"), 20); + TEST_COMPARE_STRING (buf, "Success "); + + errno = 0; + TEST_COMPARE (sprintf (buf, "%-#20m"), 20); + TEST_COMPARE_STRING (buf, "0 "); + + return 0; +} + +#include diff --git a/stdio-common/vfprintf-internal.c b/stdio-common/vfprintf-internal.c index 355ba582e6..817edd328f 100644 --- a/stdio-common/vfprintf-internal.c +++ b/stdio-common/vfprintf-internal.c @@ -936,11 +936,26 @@ static const uint8_t jump_table[] = \ LABEL (form_strerror): \ /* Print description of error ERRNO. */ \ - string = \ - (CHAR_T *) __strerror_r (save_errno, (char *) work_buffer, \ - WORK_BUFFER_SIZE * sizeof (CHAR_T)); \ - is_long = 0; /* This is no wide-char string. */ \ - goto LABEL (print_string) + if (alt) \ + string = (CHAR_T *) __get_errname (save_errno); \ + else \ + string = (CHAR_T *) __strerror_r (save_errno, (char *) work_buffer, \ + WORK_BUFFER_SIZE * sizeof (CHAR_T));\ + if (string == NULL) \ + { \ + /* Print as a decimal number. */ \ + base = 10; \ + is_negative = save_errno < 0; \ + number.word = save_errno; \ + if (is_negative) \ + number.word = -number.word; \ + goto LABEL (number); \ + } \ + else \ + { \ + is_long = 0; /* This is no wide-char string. */ \ + goto LABEL (print_string); \ + } #ifdef COMPILE_WPRINTF # define process_string_arg() \