From patchwork Mon Apr 21 15:35:54 2025 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: =?utf-8?q?Barnab=C3=A1s_P=C5=91cze?= X-Patchwork-Id: 23193 Return-Path: X-Original-To: parsemail@patchwork.libcamera.org Delivered-To: parsemail@patchwork.libcamera.org Received: from lancelot.ideasonboard.com (lancelot.ideasonboard.com [92.243.16.209]) by patchwork.libcamera.org (Postfix) with ESMTPS id DD0D0C327D for ; Mon, 21 Apr 2025 15:36:08 +0000 (UTC) Received: from lancelot.ideasonboard.com (localhost [IPv6:::1]) by lancelot.ideasonboard.com (Postfix) with ESMTP id 3211168ACE; Mon, 21 Apr 2025 17:36:06 +0200 (CEST) Authentication-Results: lancelot.ideasonboard.com; dkim=pass (1024-bit key; unprotected) header.d=ideasonboard.com header.i=@ideasonboard.com header.b="omWxDcj0"; dkim-atps=neutral Received: from perceval.ideasonboard.com (perceval.ideasonboard.com [IPv6:2001:4b98:dc2:55:216:3eff:fef7:d647]) by lancelot.ideasonboard.com (Postfix) with ESMTPS id BCD7968AC3 for ; Mon, 21 Apr 2025 17:36:00 +0200 (CEST) Received: from pb-laptop.local (185.221.143.16.nat.pool.zt.hu [185.221.143.16]) by perceval.ideasonboard.com (Postfix) with ESMTPSA id 1840D73E; Mon, 21 Apr 2025 17:33:54 +0200 (CEST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=ideasonboard.com; s=mail; t=1745249634; bh=kLmYPN72UTTxjzDEdUKeIyAXCAEfWQyE3Pjl4ZvlQ0w=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=omWxDcj0cMDfr70mJW2528gGMVkB7z2EtFGC31rCj1R2gUyBkWkb8pQBiliSdBg2y cr+THAz2HHwmo4QVla4WMoOd4fmK/8ZZ5FnhqLPVbaO5TD7o4IATfO3OdoCyi77+FZ tcQkRlthYG0Rv0fzLBDKm8wsS6TlkcppfUA5twQI= From: =?utf-8?q?Barnab=C3=A1s_P=C5=91cze?= To: libcamera-devel@lists.libcamera.org Cc: Kieran Bingham , Jacopo Mondi Subject: [PATCH v2 3/5] libcamera: controls: Implement move ctor/assignment Date: Mon, 21 Apr 2025 17:35:54 +0200 Message-ID: <20250421153556.171192-4-barnabas.pocze@ideasonboard.com> X-Mailer: git-send-email 2.49.0 In-Reply-To: <20250421153556.171192-1-barnabas.pocze@ideasonboard.com> References: <20250421153556.171192-1-barnabas.pocze@ideasonboard.com> MIME-Version: 1.0 X-BeenThere: libcamera-devel@lists.libcamera.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: libcamera-devel-bounces@lists.libcamera.org Sender: "libcamera-devel" Implement a move constructor and move assignment operator for `ControlValue`. The `ControlValue` type already has an "empty" state that is used when creating a default constructed `ControlValue`, so have the moved-from instance return to that state after move construction/assignment. This is useful, for example, for `std::vector` as most implementations will use the copy constructor when reallocating if no nothrow move constructor is available. Having a nothrow move constructor avoids the extra copies. It is also useful when using temporaries of `ControlValue` with other containers such as `std::optional`, and it also makes `ControlInfo` "cheaply" move constructible/assignable. Signed-off-by: Barnabás Pőcze Reviewed-by: Kieran Bingham Reviewed-by: Jacopo Mondi --- include/libcamera/controls.h | 26 ++++++++++++++++++++++++++ src/libcamera/controls.cpp | 18 ++++++++++++++++++ 2 files changed, 44 insertions(+) diff --git a/include/libcamera/controls.h b/include/libcamera/controls.h index 3f3580036..866d667c4 100644 --- a/include/libcamera/controls.h +++ b/include/libcamera/controls.h @@ -14,6 +14,7 @@ #include #include #include +#include #include #include @@ -165,6 +166,31 @@ public: ControlValue(const ControlValue &other); ControlValue &operator=(const ControlValue &other); + ControlValue(ControlValue &&other) noexcept + : type_(other.type_), + isArray_(std::exchange(other.isArray_, false)), + numElements_(std::exchange(other.numElements_, 0)), + storage_(std::exchange(other.storage_, {})) + { + other.type_ = ControlTypeNone; + } + + ControlValue &operator=(ControlValue &&other) noexcept + { + if (this != &other) { + release(); + + type_ = other.type_; + isArray_ = std::exchange(other.isArray_, false); + numElements_ = std::exchange(other.numElements_, 0); + storage_ = std::exchange(other.storage_, {}); + + other.type_ = ControlTypeNone; + } + + return *this; + } + ControlType type() const { return type_; } bool isNone() const { return type_ == ControlTypeNone; } bool isArray() const { return isArray_; } diff --git a/src/libcamera/controls.cpp b/src/libcamera/controls.cpp index d384e1ef7..135e87613 100644 --- a/src/libcamera/controls.cpp +++ b/src/libcamera/controls.cpp @@ -155,6 +155,24 @@ ControlValue &ControlValue::operator=(const ControlValue &other) return *this; } +/** + * \fn ControlValue::ControlValue(ControlValue &&other) noexcept + * \brief Move constructor for ControlValue + * \param[in] other The ControlValue object to move from + * + * Move constructs a ControlValue instance from \a other. + * After this operation \a other will be in the same state + * as a default constructed ControlValue instance. + */ + +/** + * \fn ControlValue &ControlValue::operator=(ControlValue &&other) noexcept + * \brief Move assignment operator for ControlValue + * \param[in] other The ControlValue object to move from + * + * \sa ControlValue::ControlValue(ControlValue &&other) + */ + /** * \fn ControlValue::type() * \brief Retrieve the data type of the value