From patchwork Wed Aug 28 12:22:57 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Mark Cave-Ayland X-Patchwork-Id: 13781222 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from lists.gnu.org (lists.gnu.org [209.51.188.17]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 0BAC8C54FA6 for ; Wed, 28 Aug 2024 12:26:13 +0000 (UTC) Received: from localhost ([::1] helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1sjHiL-0007j8-0l; Wed, 28 Aug 2024 08:23:53 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1sjHiH-0007f3-Ph for qemu-devel@nongnu.org; Wed, 28 Aug 2024 08:23:49 -0400 Received: from mail.ilande.co.uk ([2001:41c9:1:41f::167]) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1sjHiG-0001DO-BC for qemu-devel@nongnu.org; Wed, 28 Aug 2024 08:23:49 -0400 DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=ilande.co.uk; s=20220518; h=Subject:Content-Transfer-Encoding:MIME-Version: References:In-Reply-To:Message-Id:Date:To:From:Sender:Reply-To:Cc: Content-Type:Content-ID:Content-Description:Resent-Date:Resent-From: Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID; bh=8A2FICmUmjowEj9RLWXSg7/Kx8EQAw4oc04eFwo72Js=; b=rSZEKM8DBeC5Slg1ILZ2eBVoNg p6jsOBm6e4VQe3tAlI7sC75ihGSkJ3ncO/BIiYCaYDd9jwHpCwok+lstzaPJhSZ9C7bNwP3upJSSS XIOpXJ/NVYwxvmrlBDDdUcVlG9HrbzFAap34aE/r2LLXTet8ePJZhhoxQKG2w4sztJDbcDK43+q2y 9EeaKWfnun8B/6eefn2A/hlcyv8PbZgZ1Joow7onAdTp0xyjo4hewSyQIVruM12/TMcCmNNpMPvLq 8apwfXUffFCTuHtqQo8xppbDbyjAW+vz7D49r7IPJLklttxo7//XBum973i7vrrlwLyVp6veYOxVF sQ7f9DKXMZ/5GO83PTLCwJGZzTZ7Fc26DjjB60T4FshrtrwInMOy8NS0srznWu30i8lsJ0KPETDWH cGCGeYgn64J1nkSkQs3yY1a6ai4x0R9pjurVO9F6KiQniJWPVvoPXta8mf3tmQqSeD0nW3HmEZV+M oG0hX0QmOP1BcLYEeNdLRL2JAlMYkyyj2vR6Fi2qv6HLc0A8Udx4LlVTYhTak3I23nsmIMJWit6HJ 8/PFUZCs/1XMNfyqGfoC4UrZyDYcDFtKfJyyXPHM0ibK4VgMy58YQVp51Uv+DxXKnq2o7657xCECO 554uBduUFf8S9g8EBRFeuke7HTFyNvWPBLd52T394=; Received: from [2a02:8012:c93d:0:260e:bf57:a4e9:8142] (helo=cheesecake.fritz.box) by mail.ilande.co.uk with esmtpsa (TLS1.3:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.92) (envelope-from ) id 1sjHhv-000B8d-1O; Wed, 28 Aug 2024 13:23:31 +0100 From: Mark Cave-Ayland To: philmd@linaro.org, Alistair.Francis@wdc.com, tavip@google.com, qemu-devel@nongnu.org Date: Wed, 28 Aug 2024 13:22:57 +0100 Message-Id: <20240828122258.928947-9-mark.cave-ayland@ilande.co.uk> X-Mailer: git-send-email 2.39.2 In-Reply-To: <20240828122258.928947-1-mark.cave-ayland@ilande.co.uk> References: <20240828122258.928947-1-mark.cave-ayland@ilande.co.uk> MIME-Version: 1.0 X-SA-Exim-Connect-IP: 2a02:8012:c93d:0:260e:bf57:a4e9:8142 X-SA-Exim-Mail-From: mark.cave-ayland@ilande.co.uk Subject: [PATCH 8/9] fifo8: introduce fifo8_peek() function X-SA-Exim-Version: 4.2.1 (built Wed, 08 May 2019 21:11:16 +0000) X-SA-Exim-Scanned: Yes (on mail.ilande.co.uk) Received-SPF: pass client-ip=2001:41c9:1:41f::167; envelope-from=mark.cave-ayland@ilande.co.uk; helo=mail.ilande.co.uk X-Spam_score_int: -20 X-Spam_score: -2.1 X-Spam_bar: -- X-Spam_report: (-2.1 / 5.0 requ) BAYES_00=-1.9, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, SPF_HELO_NONE=0.001, SPF_PASS=-0.001, T_SCC_BODY_TEXT_LINE=-0.01 autolearn=ham autolearn_force=no X-Spam_action: no action X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org This allows uses to peek the byte at the current head of the FIFO. Signed-off-by: Mark Cave-Ayland Reviewed-by: Alistair Francis Reviewed-by: Octavian Purdila --- include/qemu/fifo8.h | 11 +++++++++++ util/fifo8.c | 6 ++++++ 2 files changed, 17 insertions(+) diff --git a/include/qemu/fifo8.h b/include/qemu/fifo8.h index d09984b146..4f768d4ee3 100644 --- a/include/qemu/fifo8.h +++ b/include/qemu/fifo8.h @@ -62,6 +62,17 @@ void fifo8_push_all(Fifo8 *fifo, const uint8_t *data, uint32_t num); */ uint8_t fifo8_pop(Fifo8 *fifo); +/** + * fifo8_peek: + * @fifo: fifo to peek from + * + * Peek the data byte at the current head of the FIFO. Clients are responsible + * for checking for emptyness using fifo8_is_empty(). + * + * Returns: The peeked data byte. + */ +uint8_t fifo8_peek(Fifo8 *fifo); + /** * fifo8_pop_buf: * @fifo: FIFO to pop from diff --git a/util/fifo8.c b/util/fifo8.c index a8f5cea158..a26da66ad2 100644 --- a/util/fifo8.c +++ b/util/fifo8.c @@ -71,6 +71,12 @@ uint8_t fifo8_pop(Fifo8 *fifo) return ret; } +uint8_t fifo8_peek(Fifo8 *fifo) +{ + assert(fifo->num > 0); + return fifo->data[fifo->head]; +} + static const uint8_t *fifo8_peekpop_bufptr(Fifo8 *fifo, uint32_t max, uint32_t skip, uint32_t *numptr, bool do_pop)