[{"id":33887,"web_url":"https://patchwork.libcamera.org/comment/33887/","msgid":"","date":"2025-04-02T13:20:28","subject":"Re: [PATCH v1] libcamera: controls: Fix\n\t`ControlInfoMap::count(unsigned int)`","submitter":{"id":143,"url":"https://patchwork.libcamera.org/api/people/143/","name":"Jacopo Mondi","email":"jacopo.mondi@ideasonboard.com"},"content":"Hi Barnabás\n\nOn Wed, Apr 02, 2025 at 01:50:10PM +0200, Barnabás Pőcze wrote:\n> The two overloads of `find()` and `at()` have the same behaviour\n> regardless of the argument type: `unsigned int` or `const ControlId *`.\n\nLooking at\n\n ControlInfoMap::at(const ControlId *id);\n ControlInfoMap::at(unsigned int key);\n\nthe first checks for the presence of *id\nin std::unordered_map while the\nlatter checks the idmap just to retrieve the ControlId *\n\nControlInfoMap::mapped_type &ControlInfoMap::at(unsigned int id)\n{\n\tASSERT(idmap_);\n\n\treturn at(idmap_->at(id));\n}\n\nThe count() implementation says\n\n\t * The ControlInfoMap and its idmap have a 1:1 mapping between their\n\t * entries\n\nto justify why it doesn't call count(const ControlId *)\n\nIs your reasoning that there's no guarantee the ControlInfoMap and\nidmap are actually in sync, and ids in the idmap might not have a\ncorresponding ControlId * in the ControlInfoMap ?\n\nBecause I have the same understanding\n\n\n> However, `count()` is not so because `count(unsigned int)` only checks\n> the `ControlIdMap`, and it does not check if the given id is actually\n> present in the map storing the `ControlInfo` objects.\n>\n> So `count()` returns 1 for every control id that is present in the\n> associated `ControlIdMap` regardless of whether there is an actual\n> entry for the `ControlId` associated with the given numeric id.\n>\n> Fix that by simply using `find()` to determine the return value.\n>\n> Signed-off-by: Barnabás Pőcze \n> ---\n> src/libcamera/controls.cpp | 10 +---------\n> 1 file changed, 1 insertion(+), 9 deletions(-)\n>\n> diff --git a/src/libcamera/controls.cpp b/src/libcamera/controls.cpp\n> index 70f6f6092..98fa7583d 100644\n> --- a/src/libcamera/controls.cpp\n> +++ b/src/libcamera/controls.cpp\n> @@ -857,15 +857,7 @@ const ControlInfoMap::mapped_type &ControlInfoMap::at(unsigned int id) const\n> */\n> ControlInfoMap::size_type ControlInfoMap::count(unsigned int id) const\n> {\n> -\tif (!idmap_)\n> -\t\treturn 0;\n> -\n> -\t/*\n> -\t * The ControlInfoMap and its idmap have a 1:1 mapping between their\n> -\t * entries, we can thus just count the matching entries in idmap to\n> -\t * avoid an additional lookup.\n> -\t */\n> -\treturn idmap_->count(id);\n> +\treturn find(id) != end();\n\nThis returns a boolean while the function should actually 'count'. As\nthis is an unordered map with unique keys, this is probably ok.\n\nOtherwise, alternatively, it could be open coded.\n\nControlInfoMap::size_type ControlInfoMap::count(unsigned int id) const\n{\n\tif (!idmap_)\n\t\treturn 0;\n\n\tauto it = idmap_->find(id);\n\tif (it == idmap_->end())\n\t\treturn 0;\n\n\treturn count(it->second);\n}\n\nHowever this does one lookup more.\n\nAs we can't have multiple entries with the same key, what you have is\nfine. I would however record the reasoning with a tiny comment\n\n /*\n * The ControlInfoMap underlaying type is an unordered_map\n * which stores unique keys, so we can just use find() here\n * to avoid an additional lookup.\n */\n\nReviewed-by: Jacopo Mondi \n\nThanks\n j\n\n\n\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 B4A2BC323E\n\tfor ;\n\tWed, 2 Apr 2025 13:20:33 +0000 (UTC)","from lancelot.ideasonboard.com (localhost [IPv6:::1])\n\tby lancelot.ideasonboard.com (Postfix) with ESMTP id 05FF16897E;\n\tWed, 2 Apr 2025 15:20:33 +0200 (CEST)","from perceval.ideasonboard.com (perceval.ideasonboard.com\n\t[IPv6:2001:4b98:dc2:55:216:3eff:fef7:d647])\n\tby lancelot.ideasonboard.com (Postfix) with ESMTPS id 7DBE568979\n\tfor ;\n\tWed, 2 Apr 2025 15:20:31 +0200 (CEST)","from ideasonboard.com (93-61-96-190.ip145.fastwebnet.it\n\t[93.61.96.190])\n\tby perceval.ideasonboard.com (Postfix) with ESMTPSA id 83BED6A2;\n\tWed, 2 Apr 2025 15:18:38 +0200 (CEST)"],"Authentication-Results":"lancelot.ideasonboard.com; dkim=pass (1024-bit key;\n\tunprotected) header.d=ideasonboard.com header.i=@ideasonboard.com\n\theader.b=\"Noa226bI\"; dkim-atps=neutral","DKIM-Signature":"v=1; a=rsa-sha256; c=relaxed/simple; d=ideasonboard.com;\n\ts=mail; t=1743599918;\n\tbh=4EPU9WqQbdHuu6oXYBXRNsz2D1GEshFV1xBLaNUzuKQ=;\n\th=Date:From:To:Cc:Subject:References:In-Reply-To:From;\n\tb=Noa226bIUg1n5Lg48EIMewO6oDfZyIWzsuz5hgiJ4ZCT/MFYGowyqFxs/GsWwpgsR\n\t5u4Bfx0O3sqZvov+fILITsKY1HSwucIJrEUOgSUrKJ9SMA/WWckKcyPkIqoNQTYprt\n\tAIasulgW6PGn7l0cjkKYMm4FMTyW+NqYtlJV0RZE=","Date":"Wed, 2 Apr 2025 15:20:28 +0200","From":"Jacopo Mondi ","To":"=?utf-8?q?Barnab=C3=A1s_P=C5=91cze?= ","Cc":"libcamera-devel@lists.libcamera.org","Subject":"Re: [PATCH v1] libcamera: controls: Fix\n\t`ControlInfoMap::count(unsigned int)`","Message-ID":"","References":"<20250402115010.937137-1-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":"<20250402115010.937137-1-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\" "}},{"id":33898,"web_url":"https://patchwork.libcamera.org/comment/33898/","msgid":"","date":"2025-04-02T16:11:58","subject":"Re: [PATCH v1] libcamera: controls: Fix\n\t`ControlInfoMap::count(unsigned int)`","submitter":{"id":216,"url":"https://patchwork.libcamera.org/api/people/216/","name":"Barnabás Pőcze","email":"barnabas.pocze@ideasonboard.com"},"content":"Hi\n\n\n2025. 04. 02. 15:20 keltezéssel, Jacopo Mondi írta:\n> Hi Barnabás\n> \n> On Wed, Apr 02, 2025 at 01:50:10PM +0200, Barnabás Pőcze wrote:\n>> The two overloads of `find()` and `at()` have the same behaviour\n>> regardless of the argument type: `unsigned int` or `const ControlId *`.\n> \n> Looking at\n> \n> ControlInfoMap::at(const ControlId *id);\n> ControlInfoMap::at(unsigned int key);\n> \n> the first checks for the presence of *id\n> in std::unordered_map while the\n> latter checks the idmap just to retrieve the ControlId *\n> \n> ControlInfoMap::mapped_type &ControlInfoMap::at(unsigned int id)\n> {\n> \tASSERT(idmap_);\n> \n> \treturn at(idmap_->at(id));\n> }\n> \n> The count() implementation says\n> \n> \t * The ControlInfoMap and its idmap have a 1:1 mapping between their\n> \t * entries\n> \n> to justify why it doesn't call count(const ControlId *)\n> \n> Is your reasoning that there's no guarantee the ControlInfoMap and\n> idmap are actually in sync, and ids in the idmap might not have a\n> corresponding ControlId * in the ControlInfoMap ?\n> \n> Because I have the same understanding\n\nI think so, yes. The motivation is `Camera::queueRequest()`:\n\n\t/* Pre-process AeEnable. */\n\tControlList &controls = request->controls();\n\tconst auto &aeEnable = controls.get(controls::AeEnable);\n\tif (aeEnable) {\n\t\tif (_d()->controlInfo_.count(controls::AnalogueGainMode.id()) &&\n\t\t !controls.contains(controls::AnalogueGainMode.id())) {\n\t\t\tcontrols.set(controls::AnalogueGainMode,\n\t\t\t\t *aeEnable ? controls::AnalogueGainModeAuto\n\t\t\t\t\t : controls::AnalogueGainModeManual);\n\t\t}\n\n\nTo me the intention is most likely that `_d()->controlInfo_.count(controls::AnalogueGainMode.id())`\nis should determine if the camera supports the control.\nHowever, it does not do that; it checks if the `ControlIdMap` of\nthe `ControlInfoMap` knows about `AnalogueGainMode`, which will\nbe true since the `ControlIdMap` is `controls::controls` for all\ncamera `ControlInfoMap`s.\n\nHowever, if the code had `_d()->controlInfo_.count(&controls::AnalogueGainMode)`\nthen it would work \"as expected\", and indeed check if the camera\nsupports the control. This patch is to get rid of this inconsistency,\nand consequently fix the check in `Camera::queueRequest()`.\n\n\nRegards,\nBarnabás Pőcze\n\n> \n> \n>> However, `count()` is not so because `count(unsigned int)` only checks\n>> the `ControlIdMap`, and it does not check if the given id is actually\n>> present in the map storing the `ControlInfo` objects.\n>>\n>> So `count()` returns 1 for every control id that is present in the\n>> associated `ControlIdMap` regardless of whether there is an actual\n>> entry for the `ControlId` associated with the given numeric id.\n>>\n>> Fix that by simply using `find()` to determine the return value.\n>>\n>> Signed-off-by: Barnabás Pőcze \n>> ---\n>> src/libcamera/controls.cpp | 10 +---------\n>> 1 file changed, 1 insertion(+), 9 deletions(-)\n>>\n>> diff --git a/src/libcamera/controls.cpp b/src/libcamera/controls.cpp\n>> index 70f6f6092..98fa7583d 100644\n>> --- a/src/libcamera/controls.cpp\n>> +++ b/src/libcamera/controls.cpp\n>> @@ -857,15 +857,7 @@ const ControlInfoMap::mapped_type &ControlInfoMap::at(unsigned int id) const\n>> */\n>> ControlInfoMap::size_type ControlInfoMap::count(unsigned int id) const\n>> {\n>> -\tif (!idmap_)\n>> -\t\treturn 0;\n>> -\n>> -\t/*\n>> -\t * The ControlInfoMap and its idmap have a 1:1 mapping between their\n>> -\t * entries, we can thus just count the matching entries in idmap to\n>> -\t * avoid an additional lookup.\n>> -\t */\n>> -\treturn idmap_->count(id);\n>> +\treturn find(id) != end();\n> \n> This returns a boolean while the function should actually 'count'. As\n> this is an unordered map with unique keys, this is probably ok.\n> \n> Otherwise, alternatively, it could be open coded.\n> \n> ControlInfoMap::size_type ControlInfoMap::count(unsigned int id) const\n> {\n> \tif (!idmap_)\n> \t\treturn 0;\n> \n> \tauto it = idmap_->find(id);\n> \tif (it == idmap_->end())\n> \t\treturn 0;\n> \n> \treturn count(it->second);\n> }\n> \n> However this does one lookup more.\n> \n> As we can't have multiple entries with the same key, what you have is\n> fine. I would however record the reasoning with a tiny comment\n> \n> /*\n> * The ControlInfoMap underlaying type is an unordered_map\n> * which stores unique keys, so we can just use find() here\n> * to avoid an additional lookup.\n> */\n> \n> Reviewed-by: Jacopo Mondi \n> \n> Thanks\n> j\n> \n> \n> \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 4890BC3213\n\tfor ;\n\tWed, 2 Apr 2025 16:12:04 +0000 (UTC)","from lancelot.ideasonboard.com (localhost [IPv6:::1])\n\tby lancelot.ideasonboard.com (Postfix) with ESMTP id 8FF476897E;\n\tWed, 2 Apr 2025 18:12:03 +0200 (CEST)","from perceval.ideasonboard.com (perceval.ideasonboard.com\n\t[213.167.242.64])\n\tby lancelot.ideasonboard.com (Postfix) with ESMTPS id 1F77968979\n\tfor ;\n\tWed, 2 Apr 2025 18:12:02 +0200 (CEST)","from [192.168.33.20] (185.221.143.221.nat.pool.zt.hu\n\t[185.221.143.221])\n\tby perceval.ideasonboard.com (Postfix) with ESMTPSA id 077C26A2;\n\tWed, 2 Apr 2025 18:10:08 +0200 (CEST)"],"Authentication-Results":"lancelot.ideasonboard.com; dkim=pass (1024-bit key;\n\tunprotected) header.d=ideasonboard.com header.i=@ideasonboard.com\n\theader.b=\"SaQfm3A3\"; dkim-atps=neutral","DKIM-Signature":"v=1; a=rsa-sha256; c=relaxed/simple; d=ideasonboard.com;\n\ts=mail; t=1743610209;\n\tbh=55ZiQmwAz7QDeh9mCUjyTLCFUtt+tnaAB117/H7e1UM=;\n\th=Date:Subject:To:Cc:References:From:In-Reply-To:From;\n\tb=SaQfm3A3NtJkePxIqTHxp2724vI7Jc+FRV3AH7KpsQ8gl8EMZYGqCmOXqf+nsBxgx\n\t5YnB37CuZw0/JQ92Rg1fVhd3o+ltjRxEW6zbt8iavvgjKJMEhNn3VxSYtUJ0def61Q\n\tuSHI0sSLGQfwsct5hbPmlCWvP9UprRuyKqtK+PXA=","Message-ID":"","Date":"Wed, 2 Apr 2025 18:11:58 +0200","MIME-Version":"1.0","User-Agent":"Mozilla Thunderbird","Subject":"Re: [PATCH v1] libcamera: controls: Fix\n\t`ControlInfoMap::count(unsigned int)`","To":"Jacopo Mondi ","Cc":"libcamera-devel@lists.libcamera.org","References":"<20250402115010.937137-1-barnabas.pocze@ideasonboard.com>\n\t","From":"=?utf-8?q?Barnab=C3=A1s_P=C5=91cze?= ","Content-Language":"en-US, hu-HU","In-Reply-To":"","Content-Type":"text/plain; charset=UTF-8; format=flowed","Content-Transfer-Encoding":"8bit","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":34222,"web_url":"https://patchwork.libcamera.org/comment/34222/","msgid":"<174714035489.233090.16117023354981988536@pyrite.rasen.tech>","date":"2025-05-13T12:45:54","subject":"Re: [PATCH v1] libcamera: controls: Fix\n\t`ControlInfoMap::count(unsigned int)`","submitter":{"id":17,"url":"https://patchwork.libcamera.org/api/people/17/","name":"Paul Elder","email":"paul.elder@ideasonboard.com"},"content":"Hi Barnabás,\n\nThanks for the patch.\n\nQuoting Barnabás Pőcze (2025-04-02 13:50:10)\n> The two overloads of `find()` and `at()` have the same behaviour\n> regardless of the argument type: `unsigned int` or `const ControlId *`.\n> However, `count()` is not so because `count(unsigned int)` only checks\n> the `ControlIdMap`, and it does not check if the given id is actually\n> present in the map storing the `ControlInfo` objects.\n> \n> So `count()` returns 1 for every control id that is present in the\n> associated `ControlIdMap` regardless of whether there is an actual\n> entry for the `ControlId` associated with the given numeric id.\n> \n> Fix that by simply using `find()` to determine the return value.\n> \n> Signed-off-by: Barnabás Pőcze \n\nLooks good to me.\n\nReviewed-by: Paul Elder \n\n> ---\n> src/libcamera/controls.cpp | 10 +---------\n> 1 file changed, 1 insertion(+), 9 deletions(-)\n> \n> diff --git a/src/libcamera/controls.cpp b/src/libcamera/controls.cpp\n> index 70f6f6092..98fa7583d 100644\n> --- a/src/libcamera/controls.cpp\n> +++ b/src/libcamera/controls.cpp\n> @@ -857,15 +857,7 @@ const ControlInfoMap::mapped_type &ControlInfoMap::at(unsigned int id) const\n> */\n> ControlInfoMap::size_type ControlInfoMap::count(unsigned int id) const\n> {\n> - if (!idmap_)\n> - return 0;\n> -\n> - /*\n> - * The ControlInfoMap and its idmap have a 1:1 mapping between their\n> - * entries, we can thus just count the matching entries in idmap to\n> - * avoid an additional lookup.\n> - */\n> - return idmap_->count(id);\n> + return find(id) != end();\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 C16C6C3220\n\tfor ;\n\tTue, 13 May 2025 12:46:00 +0000 (UTC)","from lancelot.ideasonboard.com (localhost [IPv6:::1])\n\tby lancelot.ideasonboard.com (Postfix) with ESMTP id 998E96175C;\n\tTue, 13 May 2025 14:45:59 +0200 (CEST)","from perceval.ideasonboard.com (perceval.ideasonboard.com\n\t[IPv6:2001:4b98:dc2:55:216:3eff:fef7:d647])\n\tby lancelot.ideasonboard.com (Postfix) with ESMTPS id 007136175C\n\tfor ;\n\tTue, 13 May 2025 14:45:57 +0200 (CEST)","from pyrite.rasen.tech (unknown\n\t[IPv6:2001:861:3a80:3300:4f2f:8c2c:b3ef:17d4])\n\tby perceval.ideasonboard.com (Postfix) with ESMTPSA id 2DF714C9;\n\tTue, 13 May 2025 14:45:42 +0200 (CEST)"],"Authentication-Results":"lancelot.ideasonboard.com; dkim=pass (1024-bit key;\n\tunprotected) header.d=ideasonboard.com header.i=@ideasonboard.com\n\theader.b=\"TJrT3a0J\"; dkim-atps=neutral","DKIM-Signature":"v=1; a=rsa-sha256; c=relaxed/simple; d=ideasonboard.com;\n\ts=mail; t=1747140342;\n\tbh=q9yqXY9BHoDVJIBcQ0VQSfLYf27prl1zTQm3jtA5KQc=;\n\th=In-Reply-To:References:Subject:From:To:Date:From;\n\tb=TJrT3a0JqJTfC1aZkPJe6+f8BCP5mQgiiomjvhyBVbsdGZzokV/vd98Fp+WPSUalU\n\t/et5in7wQC6WFkSaTomflT29mlYO1I7aZckAqhekxyanbnVyhdgj6YFQ5HeKlnWbua\n\tnUm4rpsMKz2735xF51m/hy0w5CNLA+QlPlJwf1ek=","Content-Type":"text/plain; charset=\"utf-8\"","MIME-Version":"1.0","Content-Transfer-Encoding":"quoted-printable","In-Reply-To":"<20250402115010.937137-1-barnabas.pocze@ideasonboard.com>","References":"<20250402115010.937137-1-barnabas.pocze@ideasonboard.com>","Subject":"Re: [PATCH v1] libcamera: controls: Fix\n\t`ControlInfoMap::count(unsigned int)`","From":"Paul Elder ","To":"=?utf-8?q?Barnab=C3=A1s_P=C5=91cze?= ,\n\tlibcamera-devel@lists.libcamera.org","Date":"Tue, 13 May 2025 14:45:54 +0200","Message-ID":"<174714035489.233090.16117023354981988536@pyrite.rasen.tech>","User-Agent":"alot/0.0.0","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\" "}}]