From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: by sourceware.org (Postfix, from userid 2178) id 258163858D33; Tue, 31 Jan 2023 21:22:26 +0000 (GMT) DKIM-Filter: OpenDKIM Filter v2.11.0 sourceware.org 258163858D33 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=sourceware.org; s=default; t=1675200146; bh=alJPvPvZp266tNfNzavGy5JosM9tMPqGPavyIImXIg0=; h=From:To:Subject:Date:From; b=Yfi13zaQ2f421werxx1bchhTX4uQ5RSAhkvLvy8VDLBt4ovE1oVWeI+Dm9MEYY6iL 2ac9wXMjstr+AQVz01iqwtQqzwVNJa5xhdPOr1qRoptPAFXrfsnuXTXq/WsL024Hix JoDlN1N6QFRfet/Yt63BP7pyF09MF9TrjKSD9vck= Content-Type: text/plain; charset="us-ascii" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit From: Florian Weimer To: glibc-cvs@sourceware.org Subject: [glibc] libio: Update number of written bytes in dprintf implementation X-Act-Checkin: glibc X-Git-Author: Florian Weimer X-Git-Refname: refs/heads/master X-Git-Oldrev: 2f39e44a8417b4186a7f15bfeac5d0b557e63e03 X-Git-Newrev: f5c65fa920d78cffe56fe4065f16241637808353 Message-Id: <20230131212226.258163858D33@sourceware.org> Date: Tue, 31 Jan 2023 21:22:26 +0000 (GMT) List-Id: https://sourceware.org/git/gitweb.cgi?p=glibc.git;h=f5c65fa920d78cffe56fe4065f16241637808353 commit f5c65fa920d78cffe56fe4065f16241637808353 Author: Florian Weimer Date: Tue Jan 31 22:22:02 2023 +0100 libio: Update number of written bytes in dprintf implementation The __printf_buffer_flush_dprintf function needs to record that the buffer has been written before reusing it. Without this accounting, dprintf always returns zero. Fixes commit 8ece45e4f586abd212d1c02d74d38ef681a45600 ("libio: Convert __vdprintf_internal to buffers"). Reviewed-by: Carlos O'Donell Tested-by: Carlos O'Donell Diff: --- libio/iovdprintf.c | 1 + stdio-common/Makefile | 1 + stdio-common/tst-dprintf-length.c | 45 +++++++++++++++++++++++++++++++++++++++ 3 files changed, 47 insertions(+) diff --git a/libio/iovdprintf.c b/libio/iovdprintf.c index fb359d263d..d9fa886fdf 100644 --- a/libio/iovdprintf.c +++ b/libio/iovdprintf.c @@ -54,6 +54,7 @@ __printf_buffer_flush_dprintf (struct __printf_buffer_dprintf *buf) } p += ret; } + buf->base.written += buf->base.write_ptr - buf->base.write_base; buf->base.write_ptr = buf->buf; } diff --git a/stdio-common/Makefile b/stdio-common/Makefile index da3034d847..34fdd6d1f8 100644 --- a/stdio-common/Makefile +++ b/stdio-common/Makefile @@ -180,6 +180,7 @@ tests := \ tst-bz11319 \ tst-bz11319-fortify2 \ tst-cookie \ + tst-dprintf-length \ tst-fdopen \ tst-ferror \ tst-fgets \ diff --git a/stdio-common/tst-dprintf-length.c b/stdio-common/tst-dprintf-length.c new file mode 100644 index 0000000000..abe2caf45a --- /dev/null +++ b/stdio-common/tst-dprintf-length.c @@ -0,0 +1,45 @@ +/* Test that dprintf returns the expected length. + Copyright (C) 2023 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 + +static int +do_test (void) +{ + /* Use a datagram socket to check that everything arrives in one packet. + The dprintf function should perform a single write call. */ + int fds[2]; + TEST_VERIFY_EXIT (socketpair (AF_LOCAL, SOCK_DGRAM, 0, fds) == 0); + + TEST_COMPARE (dprintf (fds[0], "(%d)%s[%d]", 123, "---", 4567), 14); + + char buf[32]; + ssize_t ret = read (fds[1], buf, sizeof (buf)); + TEST_VERIFY_EXIT (ret > 0); + TEST_COMPARE_BLOB (buf, ret, "(123)---[4567]", strlen ("(123)---[4567]")); + + close (fds[1]); + close (fds[0]); + return 0; +} + +#include