[{"id":33958,"web_url":"https://patchwork.libcamera.org/comment/33958/","msgid":"<174490454803.2882969.17536552906996132460@ping.linuxembedded.co.uk>","date":"2025-04-17T15:42:28","subject":"Re: [PATCH v1 1/3] libcamera: controls: Give name to the union\n\tcontaining storage","submitter":{"id":4,"url":"https://patchwork.libcamera.org/api/people/4/","name":"Kieran Bingham","email":"kieran.bingham@ideasonboard.com"},"content":"Quoting Barnabás Pőcze (2025-04-17 12:35:37)\n> In order to be able to copy the storage as one unit, regardless of\n> which member is active give a name to the union member.\n> \n> Signed-off-by: Barnabás Pőcze \n\nReviewed-by: Kieran Bingham \n\n> ---\n> include/libcamera/controls.h | 6 +++---\n> src/libcamera/controls.cpp | 17 ++++++++---------\n> 2 files changed, 11 insertions(+), 12 deletions(-)\n> \n> diff --git a/include/libcamera/controls.h b/include/libcamera/controls.h\n> index 4bfe9615c..1dc6ccffa 100644\n> --- a/include/libcamera/controls.h\n> +++ b/include/libcamera/controls.h\n> @@ -238,9 +238,9 @@ private:\n> bool isArray_;\n> std::size_t numElements_ : 32;\n> union {\n> - uint64_t value_;\n> - void *storage_;\n> - };\n> + uint64_t internal;\n> + void *external;\n> + } storage_;\n> \n> void release();\n> void set(ControlType type, bool isArray, const void *data,\n> diff --git a/src/libcamera/controls.cpp b/src/libcamera/controls.cpp\n> index 70f6f6092..d384e1ef7 100644\n> --- a/src/libcamera/controls.cpp\n> +++ b/src/libcamera/controls.cpp\n> @@ -10,6 +10,7 @@\n> #include \n> #include \n> #include \n> +#include \n> \n> #include \n> #include \n> @@ -122,10 +123,8 @@ void ControlValue::release()\n> {\n> std::size_t size = numElements_ * ControlValueSize[type_];\n> \n> - if (size > sizeof(value_)) {\n> - delete[] reinterpret_cast(storage_);\n> - storage_ = nullptr;\n> - }\n> + if (size > sizeof(storage_.internal))\n> + delete[] reinterpret_cast(std::exchange(storage_.external, nullptr));\n> }\n> \n> ControlValue::~ControlValue()\n> @@ -192,9 +191,9 @@ ControlValue &ControlValue::operator=(const ControlValue &other)\n> Span ControlValue::data() const\n> {\n> std::size_t size = numElements_ * ControlValueSize[type_];\n> - const uint8_t *data = size > sizeof(value_)\n> - ? reinterpret_cast(storage_)\n> - : reinterpret_cast(&value_);\n> + const uint8_t *data = size > sizeof(storage_.internal)\n> + ? reinterpret_cast(storage_.external)\n> + : reinterpret_cast(&storage_.internal);\n> return { data, size };\n> }\n> \n> @@ -391,8 +390,8 @@ void ControlValue::reserve(ControlType type, bool isArray, std::size_t numElemen\n> if (oldSize == newSize)\n> return;\n> \n> - if (newSize > sizeof(value_))\n> - storage_ = reinterpret_cast(new uint8_t[newSize]);\n> + if (newSize > sizeof(storage_.internal))\n> + storage_.external = new uint8_t[newSize];\n> }\n> \n> /**\n> -- \n> 2.49.0\n>","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 92AC4C327D\n\tfor ;\n\tThu, 17 Apr 2025 15:42:34 +0000 (UTC)","from lancelot.ideasonboard.com (localhost [IPv6:::1])\n\tby lancelot.ideasonboard.com (Postfix) with ESMTP id AA3D268AC2;\n\tThu, 17 Apr 2025 17:42:33 +0200 (CEST)","from perceval.ideasonboard.com (perceval.ideasonboard.com\n\t[213.167.242.64])\n\tby lancelot.ideasonboard.com (Postfix) with ESMTPS id 2B5AA68AC0\n\tfor ;\n\tThu, 17 Apr 2025 17:42:31 +0200 (CEST)","from pendragon.ideasonboard.com\n\t(cpc89244-aztw30-2-0-cust6594.18-1.cable.virginm.net [86.31.185.195])\n\tby perceval.ideasonboard.com (Postfix) with ESMTPSA id 55870415;\n\tThu, 17 Apr 2025 17:40:27 +0200 (CEST)"],"Authentication-Results":"lancelot.ideasonboard.com; dkim=pass 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,\n\tlibcamera-devel@lists.libcamera.org","Date":"Thu, 17 Apr 2025 16:42:28 +0100","Message-ID":"<174490454803.2882969.17536552906996132460@ping.linuxembedded.co.uk>","User-Agent":"alot/0.10","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","Errors-To":"libcamera-devel-bounces@lists.libcamera.org","Sender":"\"libcamera-devel\" "}},{"id":33965,"web_url":"https://patchwork.libcamera.org/comment/33965/","msgid":"","date":"2025-04-18T10:15:52","subject":"Re: [PATCH v1 1/3] libcamera: controls: Give name to the union\n\tcontaining storage","submitter":{"id":143,"url":"https://patchwork.libcamera.org/api/people/143/","name":"Jacopo Mondi","email":"jacopo.mondi@ideasonboard.com"},"content":"Hi Barnabás\n\nOn Thu, Apr 17, 2025 at 01:35:37PM +0200, Barnabás Pőcze wrote:\n> In order to be able to copy the storage as one unit, regardless of\n> which member is active give a name to the union member.\n>\n> Signed-off-by: Barnabás Pőcze \n> ---\n> include/libcamera/controls.h | 6 +++---\n> src/libcamera/controls.cpp | 17 ++++++++---------\n> 2 files changed, 11 insertions(+), 12 deletions(-)\n>\n> diff --git a/include/libcamera/controls.h b/include/libcamera/controls.h\n> index 4bfe9615c..1dc6ccffa 100644\n> --- a/include/libcamera/controls.h\n> +++ b/include/libcamera/controls.h\n> @@ -238,9 +238,9 @@ private:\n> \tbool isArray_;\n> \tstd::size_t numElements_ : 32;\n> \tunion {\n> -\t\tuint64_t value_;\n> -\t\tvoid *storage_;\n> -\t};\n> +\t\tuint64_t internal;\n> +\t\tvoid *external;\n\nWe could nitpick on names here, but I won't :)\n\nReviewed-by: Jacopo Mondi \n\n> +\t} storage_;\n>\n> \tvoid release();\n> \tvoid set(ControlType type, bool isArray, const void *data,\n> diff --git a/src/libcamera/controls.cpp b/src/libcamera/controls.cpp\n> index 70f6f6092..d384e1ef7 100644\n> --- a/src/libcamera/controls.cpp\n> +++ b/src/libcamera/controls.cpp\n> @@ -10,6 +10,7 @@\n> #include \n> #include \n> #include \n> +#include \n>\n> #include \n> #include \n> @@ -122,10 +123,8 @@ void ControlValue::release()\n> {\n> \tstd::size_t size = numElements_ * ControlValueSize[type_];\n>\n> -\tif (size > sizeof(value_)) {\n> -\t\tdelete[] reinterpret_cast(storage_);\n> -\t\tstorage_ = nullptr;\n> -\t}\n> +\tif (size > sizeof(storage_.internal))\n> +\t\tdelete[] reinterpret_cast(std::exchange(storage_.external, nullptr));\n> }\n>\n> ControlValue::~ControlValue()\n> @@ -192,9 +191,9 @@ ControlValue &ControlValue::operator=(const ControlValue &other)\n> Span ControlValue::data() const\n> {\n> \tstd::size_t size = numElements_ * ControlValueSize[type_];\n> -\tconst uint8_t *data = size > sizeof(value_)\n> -\t\t\t ? reinterpret_cast(storage_)\n> -\t\t\t : reinterpret_cast(&value_);\n> +\tconst uint8_t *data = size > sizeof(storage_.internal)\n> +\t\t\t ? reinterpret_cast(storage_.external)\n> +\t\t\t : reinterpret_cast(&storage_.internal);\n> \treturn { data, size };\n> }\n>\n> @@ -391,8 +390,8 @@ void ControlValue::reserve(ControlType type, bool isArray, std::size_t numElemen\n> \tif (oldSize == newSize)\n> \t\treturn;\n>\n> -\tif (newSize > sizeof(value_))\n> -\t\tstorage_ = reinterpret_cast(new uint8_t[newSize]);\n> +\tif (newSize > sizeof(storage_.internal))\n> +\t\tstorage_.external = new uint8_t[newSize];\n> }\n>\n> /**\n> --\n> 2.49.0\n>","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 00655C327D\n\tfor ;\n\tFri, 18 Apr 2025 10:15:57 +0000 (UTC)","from lancelot.ideasonboard.com (localhost [IPv6:::1])\n\tby lancelot.ideasonboard.com (Postfix) with ESMTP id 69014617E8;\n\tFri, 18 Apr 2025 12:15:57 +0200 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Apr 2025 12:15:52 +0200","From":"Jacopo Mondi ","To":"=?utf-8?q?Barnab=C3=A1s_P=C5=91cze?= ","Cc":"libcamera-devel@lists.libcamera.org","Subject":"Re: [PATCH v1 1/3] libcamera: controls: Give name to the union\n\tcontaining storage","Message-ID":"","References":"<20250417113539.1137936-1-barnabas.pocze@ideasonboard.com>","MIME-Version":"1.0","Content-Type":"text/plain; charset=utf-8","Content-Disposition":"inline","Content-Transfer-Encoding":"8bit","In-Reply-To":"<20250417113539.1137936-1-barnabas.pocze@ideasonboard.com>","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","Errors-To":"libcamera-devel-bounces@lists.libcamera.org","Sender":"\"libcamera-devel\" "}}]