From patchwork Tue Sep 6 13:56:05 2016 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: =?utf-8?q?Daniel_P=2E_Berrang=C3=A9?= X-Patchwork-Id: 9317013 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork.web.codeaurora.org (Postfix) with ESMTP id E2AF8601C0 for ; Tue, 6 Sep 2016 14:03:36 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id D2DC828BF4 for ; Tue, 6 Sep 2016 14:03:36 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id C7B0E28BFF; Tue, 6 Sep 2016 14:03:36 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-6.9 required=2.0 tests=BAYES_00,RCVD_IN_DNSWL_HI autolearn=ham version=3.3.1 Received: from lists.gnu.org (lists.gnu.org [208.118.235.17]) (using TLSv1 with cipher AES256-SHA (256/256 bits)) (No client certificate requested) by mail.wl.linuxfoundation.org (Postfix) with ESMTPS id 710DC28C14 for ; Tue, 6 Sep 2016 14:03:36 +0000 (UTC) Received: from localhost ([::1]:33661 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1bhGyN-0001Ep-LC for patchwork-qemu-devel@patchwork.kernel.org; Tue, 06 Sep 2016 10:03:35 -0400 Received: from eggs.gnu.org ([2001:4830:134:3::10]:37643) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1bhGrP-0004K2-Gv for qemu-devel@nongnu.org; Tue, 06 Sep 2016 09:56:24 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1bhGrK-0006C1-0R for qemu-devel@nongnu.org; Tue, 06 Sep 2016 09:56:22 -0400 Received: from mx1.redhat.com ([209.132.183.28]:34304) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1bhGrJ-0006Bi-OZ for qemu-devel@nongnu.org; Tue, 06 Sep 2016 09:56:17 -0400 Received: from int-mx11.intmail.prod.int.phx2.redhat.com (int-mx11.intmail.prod.int.phx2.redhat.com [10.5.11.24]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id 4450685365 for ; Tue, 6 Sep 2016 13:56:17 +0000 (UTC) Received: from t530wlan.home.berrange.com.com (vpn1-6-152.ams2.redhat.com [10.36.6.152]) by int-mx11.intmail.prod.int.phx2.redhat.com (8.14.4/8.14.4) with ESMTP id u86DuBkV009987; Tue, 6 Sep 2016 09:56:16 -0400 From: "Daniel P. Berrange" To: qemu-devel@nongnu.org Date: Tue, 6 Sep 2016 14:56:05 +0100 Message-Id: <1473170165-540-5-git-send-email-berrange@redhat.com> In-Reply-To: <1473170165-540-1-git-send-email-berrange@redhat.com> References: <1473170165-540-1-git-send-email-berrange@redhat.com> X-Scanned-By: MIMEDefang 2.68 on 10.5.11.24 X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.5.110.25]); Tue, 06 Sep 2016 13:56:17 +0000 (UTC) X-detected-operating-system: by eggs.gnu.org: GNU/Linux 2.2.x-3.x [generic] X-Received-From: 209.132.183.28 Subject: [Qemu-devel] [PATCH v2 4/4] char: convert qemu_chr_fe_write to qemu_chr_fe_write_all X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.21 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Paolo Bonzini Errors-To: qemu-devel-bounces+patchwork-qemu-devel=patchwork.kernel.org@nongnu.org Sender: "Qemu-devel" X-Virus-Scanned: ClamAV using ClamSMTP The mux chardev was not checking the return value of any qemu_chr_fe_write() call so would silently loose data on EAGAIN. Similarly the qemu_chr_fe_printf method would not check errors and was not in a position to retry even if it could check. Signed-off-by: Daniel P. Berrange --- qemu-char.c | 18 ++++++++++++------ 1 file changed, 12 insertions(+), 6 deletions(-) diff --git a/qemu-char.c b/qemu-char.c index 5f82ebb..6104f24 100644 --- a/qemu-char.c +++ b/qemu-char.c @@ -440,7 +440,9 @@ void qemu_chr_fe_printf(CharDriverState *s, const char *fmt, ...) va_list ap; va_start(ap, fmt); vsnprintf(buf, sizeof(buf), fmt, ap); - qemu_chr_fe_write(s, (uint8_t *)buf, strlen(buf)); + /* XXX this blocks entire thread. Rewrite to use + * qemu_chr_fe_write and background I/O callbacks */ + qemu_chr_fe_write_all(s, (uint8_t *)buf, strlen(buf)); va_end(ap); } @@ -556,7 +558,9 @@ static int mux_chr_write(CharDriverState *chr, const uint8_t *buf, int len) (secs / 60) % 60, secs % 60, (int)(ti % 1000)); - qemu_chr_fe_write(d->drv, (uint8_t *)buf1, strlen(buf1)); + /* XXX this blocks entire thread. Rewrite to use + * qemu_chr_fe_write and background I/O callbacks */ + qemu_chr_fe_write_all(d->drv, (uint8_t *)buf1, strlen(buf1)); d->linestart = 0; } ret += qemu_chr_fe_write(d->drv, buf+i, 1); @@ -594,13 +598,15 @@ static void mux_print_help(CharDriverState *chr) "\n\rEscape-Char set to Ascii: 0x%02x\n\r\n\r", term_escape_char); } - qemu_chr_fe_write(chr, (uint8_t *)cbuf, strlen(cbuf)); + /* XXX this blocks entire thread. Rewrite to use + * qemu_chr_fe_write and background I/O callbacks */ + qemu_chr_fe_write_all(chr, (uint8_t *)cbuf, strlen(cbuf)); for (i = 0; mux_help[i] != NULL; i++) { for (j=0; mux_help[i][j] != '\0'; j++) { if (mux_help[i][j] == '%') - qemu_chr_fe_write(chr, (uint8_t *)ebuf, strlen(ebuf)); + qemu_chr_fe_write_all(chr, (uint8_t *)ebuf, strlen(ebuf)); else - qemu_chr_fe_write(chr, (uint8_t *)&mux_help[i][j], 1); + qemu_chr_fe_write_all(chr, (uint8_t *)&mux_help[i][j], 1); } } } @@ -625,7 +631,7 @@ static int mux_proc_byte(CharDriverState *chr, MuxDriver *d, int ch) case 'x': { const char *term = "QEMU: Terminated\n\r"; - qemu_chr_fe_write(chr, (uint8_t *)term, strlen(term)); + qemu_chr_fe_write_all(chr, (uint8_t *)term, strlen(term)); exit(0); break; }