[{"id":26894,"web_url":"https://patchwork.libcamera.org/comment/26894/","msgid":"<20230418161449.GJ30837@pendragon.ideasonboard.com>","date":"2023-04-18T16:14:49","subject":"Re: [libcamera-devel] [PATCH] libcamera: device_enumerator_udev:\n\tUse std::string_view","submitter":{"id":2,"url":"https://patchwork.libcamera.org/api/people/2/","name":"Laurent Pinchart","email":"laurent.pinchart@ideasonboard.com"},"content":"Hi Barnabás,\n\nThank you for the patch.\n\nOn Tue, Apr 18, 2023 at 04:03:03PM +0000, Barnabás Pőcze via libcamera-devel wrote:\n> In `udevNotify()`, use `std::string_view` and defer the necessary\n> `std::string` construction to the last possible point.\n\nThe commit message should explain why this is a good idea.\n\n> Signed-off-by: Barnabás Pőcze \n> ---\n> src/libcamera/device_enumerator_udev.cpp | 9 +++++----\n> 1 file changed, 5 insertions(+), 4 deletions(-)\n> \n> diff --git a/src/libcamera/device_enumerator_udev.cpp b/src/libcamera/device_enumerator_udev.cpp\n> index a63cd360..0abc1248 100644\n> --- a/src/libcamera/device_enumerator_udev.cpp\n> +++ b/src/libcamera/device_enumerator_udev.cpp\n> @@ -13,6 +13,7 @@\n> #include \n> #include \n> #include \n> +#include \n> #include \n> #include \n> #include \n> @@ -331,18 +332,18 @@ int DeviceEnumeratorUdev::addV4L2Device(dev_t devnum)\n> void DeviceEnumeratorUdev::udevNotify()\n> {\n> \tstruct udev_device *dev = udev_monitor_receive_device(monitor_);\n> -\tstd::string action(udev_device_get_action(dev));\n> -\tstd::string deviceNode(udev_device_get_devnode(dev));\n> +\tstd::string_view action(udev_device_get_action(dev));\n> +\tstd::string_view deviceNode(udev_device_get_devnode(dev));\n> \n> \tLOG(DeviceEnumerator, Debug)\n> -\t\t<< action << \" device \" << udev_device_get_devnode(dev);\n> +\t\t<< action << \" device \" << deviceNode;\n> \n> \tif (action == \"add\") {\n> \t\taddUdevDevice(dev);\n> \t} else if (action == \"remove\") {\n> \t\tconst char *subsystem = udev_device_get_subsystem(dev);\n> \t\tif (subsystem && !strcmp(subsystem, \"media\"))\n> -\t\t\tremoveDevice(deviceNode);\n> +\t\t\tremoveDevice(std::string(deviceNode));\n> \t}\n> \n> \tudev_device_unref(dev);","headers":{"Return-Path":"","X-Original-To":"parsemail@patchwork.libcamera.org","Delivered-To":"parsemail@patchwork.libcamera.org","Received":["from lancelot.ideasonboard.com (lancelot.ideasonboard.com\n\t[92.243.16.209])\n\tby patchwork.libcamera.org (Postfix) with ESMTPS id 4CA5CBD1F1\n\tfor ;\n\tTue, 18 Apr 2023 16:14:40 +0000 (UTC)","from lancelot.ideasonboard.com (localhost [IPv6:::1])\n\tby lancelot.ideasonboard.com (Postfix) with ESMTP id C42C2627B8;\n\tTue, 18 Apr 2023 18:14:39 +0200 (CEST)","from perceval.ideasonboard.com (perceval.ideasonboard.com\n\t[213.167.242.64])\n\tby lancelot.ideasonboard.com (Postfix) with ESMTPS id 18039603A2\n\tfor ;\n\tTue, 18 Apr 2023 18:14:38 +0200 (CEST)","from pendragon.ideasonboard.com\n\t(133-32-181-51.west.xps.vectant.ne.jp [133.32.181.51])\n\tby perceval.ideasonboard.com (Postfix) with ESMTPSA id E92F5DE5;\n\tTue, 18 Apr 2023 18:14:30 +0200 (CEST)"],"DKIM-Signature":["v=1; 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dkim=pass (1024-bit key; \n\tunprotected) header.d=ideasonboard.com\n\theader.i=@ideasonboard.com\n\theader.b=\"YO96A2Hw\"; dkim-atps=neutral","Date":"Tue, 18 Apr 2023 19:14:49 +0300","To":"=?utf-8?q?Barnab=C3=A1s_P=C5=91cze?= ","Message-ID":"<20230418161449.GJ30837@pendragon.ideasonboard.com>","References":"<20230418160301.445828-1-pobrn@protonmail.com>","MIME-Version":"1.0","Content-Type":"text/plain; charset=utf-8","Content-Disposition":"inline","Content-Transfer-Encoding":"8bit","In-Reply-To":"<20230418160301.445828-1-pobrn@protonmail.com>","Subject":"Re: [libcamera-devel] [PATCH] libcamera: device_enumerator_udev:\n\tUse std::string_view","X-BeenThere":"libcamera-devel@lists.libcamera.org","X-Mailman-Version":"2.1.29","Precedence":"list","List-Id":"","List-Unsubscribe":",\n\t","List-Archive":"","List-Post":"","List-Help":"","List-Subscribe":",\n\t","From":"Laurent Pinchart via libcamera-devel\n\t","Reply-To":"Laurent Pinchart ","Cc":"libcamera-devel@lists.libcamera.org","Errors-To":"libcamera-devel-bounces@lists.libcamera.org","Sender":"\"libcamera-devel\" "}}]