[{"id":34662,"web_url":"https://patchwork.libcamera.org/comment/34662/","msgid":"<20250626131027.GP8738@pendragon.ideasonboard.com>","date":"2025-06-26T13:10:27","subject":"Re: [PATCH v1 1/2] libcamera: device_enumerator: Use regex to match\n\tentity names","submitter":{"id":2,"url":"https://patchwork.libcamera.org/api/people/2/","name":"Laurent Pinchart","email":"laurent.pinchart@ideasonboard.com"},"content":"Hi Dan,\n\nThank you for the patch.\n\nOn Wed, Jun 25, 2025 at 04:53:07PM +0100, Daniel Scally wrote:\n> Some entities in a media graph have names that might differ from\n> implementation to implementation; for example the Camera Receiver\n> Unit and CSI-2 receiver on the KakiP board have entities with names\n> that include their address, in the form \"csi-16000400.csi2\". Passing\n> that entity name to DeviceMatch is too inflexible given it would only\n> work if that specific CSI-2 receiver were the one being used.\n> \n> Update DeviceMatch.add() such that the string passed to it is used to\n> create a std::basic_regex, and use std::regex_search() instead of a\n> direct string comparison in DeviceMatch::match(). This allows us to\n> pass a string that will form a regex expression to match to the entity\n> instead, for example \"csi-[0-9]{8}.csi2\".\n\nSo you'll only support SoCs whose CSI-2 receiver are mapped to an\naddress that contains no alphabetic digits ? :-)\n\n> \n> Signed-off-by: Daniel Scally \n> ---\n> .../libcamera/internal/device_enumerator.h | 3 ++-\n> src/libcamera/device_enumerator.cpp | 27 ++++++++++---------\n> 2 files changed, 16 insertions(+), 14 deletions(-)\n> \n> diff --git a/include/libcamera/internal/device_enumerator.h b/include/libcamera/internal/device_enumerator.h\n> index db3532a9..fce7f0ea 100644\n> --- a/include/libcamera/internal/device_enumerator.h\n> +++ b/include/libcamera/internal/device_enumerator.h\n> @@ -8,6 +8,7 @@\n> #pragma once\n> \n> #include \n> +#include \n\nSee commit b01918978c82 (\"libcamera: v4l2_subdevice: Work around false\npositive warning\").\n\n> #include \n> #include \n> \n> @@ -28,7 +29,7 @@ public:\n> \n> private:\n> \tstd::string driver_;\n> -\tstd::vector entities_;\n> +\tstd::vector entities_;\n> };\n> \n> class DeviceEnumerator\n> diff --git a/src/libcamera/device_enumerator.cpp b/src/libcamera/device_enumerator.cpp\n> index ae17862f..e22d2822 100644\n> --- a/src/libcamera/device_enumerator.cpp\n> +++ b/src/libcamera/device_enumerator.cpp\n> @@ -52,15 +52,15 @@ LOG_DEFINE_CATEGORY(DeviceEnumerator)\n> * device enumerator to find matching media devices.\n> *\n> * A DeviceMatch is created with a specific Linux device driver in mind,\n> - * therefore the name of the driver is a required property. One or more Entity\n> - * names can be added as match criteria.\n> + * therefore the name of the driver is a required property. Regex expressions to\n> + * match one or more Entity names can be added as match criteria.\n> *\n> - * Pipeline handlers are recommended to add entities to DeviceMatch as\n> - * appropriate to ensure that the media device they need can be uniquely\n> - * identified. This is useful when the corresponding kernel driver can produce\n> - * different graphs, for instance as a result of different driver versions or\n> - * hardware configurations, and not all those graphs are suitable for a pipeline\n> - * handler.\n> + * Pipeline handlers are recommended to add regex expressions for entities to\n> + * DeviceMatch as appropriate to ensure that the media device they need can be\n> + * uniquely identified. This is useful when the corresponding kernel driver can\n> + * produce different graphs, for instance as a result of different driver\n> + * versions or hardware configurations, and not all those graphs are suitable\n> + * for a pipeline handler.\n> */\n> \n> /**\n> @@ -73,12 +73,13 @@ DeviceMatch::DeviceMatch(const std::string &driver)\n> }\n> \n> /**\n> - * \\brief Add a media entity name to the search pattern\n> - * \\param[in] entity The name of the entity in the media graph\n> + * \\brief Add a media entity regex string to the search pattern\n> + * \\param[in] entity A regex string to match the entity in the media graph\n> */\n> void DeviceMatch::add(const std::string &entity)\n> {\n> -\tentities_.push_back(entity);\n> +\tstd::regex entity_regex(entity);\n\ncamelCase. Same below.\n\n> +\tentities_.push_back(entity_regex);\n\nConstruct in-place with emplace_back, don't use a local variable.\n\n> }\n> \n> /**\n> @@ -96,11 +97,11 @@ bool DeviceMatch::match(const MediaDevice *device) const\n> \tif (driver_ != device->driver())\n> \t\treturn false;\n> \n> -\tfor (const std::string &name : entities_) {\n> +\tfor (const std::regex &name_regex : entities_) {\n> \t\tbool found = false;\n> \n> \t\tfor (const MediaEntity *entity : device->entities()) {\n> -\t\t\tif (name == entity->name()) {\n> +\t\t\tif (std::regex_search(entity->name(), name_regex)) {\n> \t\t\t\tif (!entity->deviceNode().empty()) {\n> \t\t\t\t\tfound = true;\n> \t\t\t\t\tbreak;","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 BBEE1BDCBF\n\tfor ;\n\tThu, 26 Jun 2025 13:10:55 +0000 (UTC)","from lancelot.ideasonboard.com (localhost [IPv6:::1])\n\tby lancelot.ideasonboard.com (Postfix) with ESMTP id 2067868DF9;\n\tThu, 26 Jun 2025 15:10:54 +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 8702C68DE8\n\tfor ;\n\tThu, 26 Jun 2025 15:10:52 +0200 (CEST)","from pendragon.ideasonboard.com (85-76-34-12-nat.elisa-mobile.fi\n\t[85.76.34.12])\n\tby perceval.ideasonboard.com (Postfix) with UTF8SMTPSA id 1455F6AE;\n\tThu, 26 Jun 2025 15:10:32 +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=\"KK/T8KD3\"; dkim-atps=neutral","DKIM-Signature":"v=1; a=rsa-sha256; c=relaxed/simple; d=ideasonboard.com;\n\ts=mail; t=1750943433;\n\tbh=KTakngmyn3ueks8V95Fh0EgFoWJloH2f3XINVVSBzDs=;\n\th=Date:From:To:Cc:Subject:References:In-Reply-To:From;\n\tb=KK/T8KD336BJq4lMsSrchAXyBIs6co4enCxTqKcTl5yQwF79EtsHdsOg07+E3JSy2\n\tFVKEDaQ2XjChyD7U/Qe0GWvy8DtoVrEBcwPCCd8xZa54XHTuO4FONjMavS4ZZLTrX3\n\tjC0I15aerus9TF3yX/giOyusF7dEWf4SzqXrHF1E=","Date":"Thu, 26 Jun 2025 16:10:27 +0300","From":"Laurent Pinchart ","To":"Daniel Scally ","Cc":"libcamera-devel@lists.libcamera.org","Subject":"Re: [PATCH v1 1/2] libcamera: device_enumerator: Use regex to match\n\tentity names","Message-ID":"<20250626131027.GP8738@pendragon.ideasonboard.com>","References":"<20250625155308.2325438-1-dan.scally@ideasonboard.com>\n\t<20250625155308.2325438-2-dan.scally@ideasonboard.com>","MIME-Version":"1.0","Content-Type":"text/plain; charset=utf-8","Content-Disposition":"inline","In-Reply-To":"<20250625155308.2325438-2-dan.scally@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":34663,"web_url":"https://patchwork.libcamera.org/comment/34663/","msgid":"<20250626131122.GQ8738@pendragon.ideasonboard.com>","date":"2025-06-26T13:11:22","subject":"Re: [PATCH v1 1/2] libcamera: device_enumerator: Use regex to match\n\tentity names","submitter":{"id":2,"url":"https://patchwork.libcamera.org/api/people/2/","name":"Laurent Pinchart","email":"laurent.pinchart@ideasonboard.com"},"content":"On Thu, Jun 26, 2025 at 04:10:31PM +0300, Laurent Pinchart wrote:\n> Hi Dan,\n> \n> Thank you for the patch.\n> \n> On Wed, Jun 25, 2025 at 04:53:07PM +0100, Daniel Scally wrote:\n> > Some entities in a media graph have names that might differ from\n> > implementation to implementation; for example the Camera Receiver\n> > Unit and CSI-2 receiver on the KakiP board have entities with names\n> > that include their address, in the form \"csi-16000400.csi2\". Passing\n> > that entity name to DeviceMatch is too inflexible given it would only\n> > work if that specific CSI-2 receiver were the one being used.\n> > \n> > Update DeviceMatch.add() such that the string passed to it is used to\n> > create a std::basic_regex, and use std::regex_search() instead of a\n> > direct string comparison in DeviceMatch::match(). This allows us to\n> > pass a string that will form a regex expression to match to the entity\n> > instead, for example \"csi-[0-9]{8}.csi2\".\n> \n> So you'll only support SoCs whose CSI-2 receiver are mapped to an\n> address that contains no alphabetic digits ? :-)\n\nAlso note that the '.' in the regex can now match any character. Do we\nneed to update all users of DeviceMatch to escape '.' ?\n\n> > Signed-off-by: Daniel Scally \n> > ---\n> > .../libcamera/internal/device_enumerator.h | 3 ++-\n> > src/libcamera/device_enumerator.cpp | 27 ++++++++++---------\n> > 2 files changed, 16 insertions(+), 14 deletions(-)\n> > \n> > diff --git a/include/libcamera/internal/device_enumerator.h b/include/libcamera/internal/device_enumerator.h\n> > index db3532a9..fce7f0ea 100644\n> > --- a/include/libcamera/internal/device_enumerator.h\n> > +++ b/include/libcamera/internal/device_enumerator.h\n> > @@ -8,6 +8,7 @@\n> > #pragma once\n> > \n> > #include \n> > +#include \n> \n> See commit b01918978c82 (\"libcamera: v4l2_subdevice: Work around false\n> positive warning\").\n> \n> > #include \n> > #include \n> > \n> > @@ -28,7 +29,7 @@ public:\n> > \n> > private:\n> > \tstd::string driver_;\n> > -\tstd::vector entities_;\n> > +\tstd::vector entities_;\n> > };\n> > \n> > class DeviceEnumerator\n> > diff --git a/src/libcamera/device_enumerator.cpp b/src/libcamera/device_enumerator.cpp\n> > index ae17862f..e22d2822 100644\n> > --- a/src/libcamera/device_enumerator.cpp\n> > +++ b/src/libcamera/device_enumerator.cpp\n> > @@ -52,15 +52,15 @@ LOG_DEFINE_CATEGORY(DeviceEnumerator)\n> > * device enumerator to find matching media devices.\n> > *\n> > * A DeviceMatch is created with a specific Linux device driver in mind,\n> > - * therefore the name of the driver is a required property. One or more Entity\n> > - * names can be added as match criteria.\n> > + * therefore the name of the driver is a required property. Regex expressions to\n> > + * match one or more Entity names can be added as match criteria.\n> > *\n> > - * Pipeline handlers are recommended to add entities to DeviceMatch as\n> > - * appropriate to ensure that the media device they need can be uniquely\n> > - * identified. This is useful when the corresponding kernel driver can produce\n> > - * different graphs, for instance as a result of different driver versions or\n> > - * hardware configurations, and not all those graphs are suitable for a pipeline\n> > - * handler.\n> > + * Pipeline handlers are recommended to add regex expressions for entities to\n> > + * DeviceMatch as appropriate to ensure that the media device they need can be\n> > + * uniquely identified. This is useful when the corresponding kernel driver can\n> > + * produce different graphs, for instance as a result of different driver\n> > + * versions or hardware configurations, and not all those graphs are suitable\n> > + * for a pipeline handler.\n> > */\n> > \n> > /**\n> > @@ -73,12 +73,13 @@ DeviceMatch::DeviceMatch(const std::string &driver)\n> > }\n> > \n> > /**\n> > - * \\brief Add a media entity name to the search pattern\n> > - * \\param[in] entity The name of the entity in the media graph\n> > + * \\brief Add a media entity regex string to the search pattern\n> > + * \\param[in] entity A regex string to match the entity in the media graph\n> > */\n> > void DeviceMatch::add(const std::string &entity)\n> > {\n> > -\tentities_.push_back(entity);\n> > +\tstd::regex entity_regex(entity);\n> \n> camelCase. Same below.\n> \n> > +\tentities_.push_back(entity_regex);\n> \n> Construct in-place with emplace_back, don't use a local variable.\n> \n> > }\n> > \n> > /**\n> > @@ -96,11 +97,11 @@ bool DeviceMatch::match(const MediaDevice *device) const\n> > \tif (driver_ != device->driver())\n> > \t\treturn false;\n> > \n> > -\tfor (const std::string &name : entities_) {\n> > +\tfor (const std::regex &name_regex : entities_) {\n> > \t\tbool found = false;\n> > \n> > \t\tfor (const MediaEntity *entity : device->entities()) {\n> > -\t\t\tif (name == entity->name()) {\n> > +\t\t\tif (std::regex_search(entity->name(), name_regex)) {\n> > \t\t\t\tif (!entity->deviceNode().empty()) {\n> > \t\t\t\t\tfound = true;\n> > \t\t\t\t\tbreak;\n> \n> -- \n> Regards,\n> \n> Laurent Pinchart","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 3414ABDCBF\n\tfor ;\n\tThu, 26 Jun 2025 13:11:47 +0000 (UTC)","from lancelot.ideasonboard.com (localhost [IPv6:::1])\n\tby lancelot.ideasonboard.com (Postfix) with ESMTP id CF20168DF6;\n\tThu, 26 Jun 2025 15:11:46 +0200 (CEST)","from perceval.ideasonboard.com (perceval.ideasonboard.com\n\t[213.167.242.64])\n\tby lancelot.ideasonboard.com (Postfix) with ESMTPS id E4B2A68DE8\n\tfor ;\n\tThu, 26 Jun 2025 15:11:45 +0200 (CEST)","from pendragon.ideasonboard.com (85-76-34-12-nat.elisa-mobile.fi\n\t[85.76.34.12])\n\tby perceval.ideasonboard.com (Postfix) with UTF8SMTPSA id EDAD76AE;\n\tThu, 26 Jun 2025 15:11:26 +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=\"U4u1CddP\"; dkim-atps=neutral","DKIM-Signature":"v=1; a=rsa-sha256; c=relaxed/simple; d=ideasonboard.com;\n\ts=mail; t=1750943487;\n\tbh=1YlXQHtHh0pPgvcDJcNKoeiEhCsgAHImzN4HwVEuTvQ=;\n\th=Date:From:To:Cc:Subject:References:In-Reply-To:From;\n\tb=U4u1CddPTaQksxgGbwF/WcmLHR6+36iPpxFedKQE6YFQ0y6w0q2+YqB/ZwhWpFDV5\n\ter0AnrZN7wNVxxYtUhFf9kZxXxJ/9lDWnvC5pVCWMPpbzLjZUjF4uPFjH1R9CN5yXN\n\tLibdIt9w4Vf6IpMFKKuYEOSRVMqjCIeCOqev/coY=","Date":"Thu, 26 Jun 2025 16:11:22 +0300","From":"Laurent Pinchart ","To":"Daniel Scally ","Cc":"libcamera-devel@lists.libcamera.org","Subject":"Re: [PATCH v1 1/2] libcamera: device_enumerator: Use regex to match\n\tentity names","Message-ID":"<20250626131122.GQ8738@pendragon.ideasonboard.com>","References":"<20250625155308.2325438-1-dan.scally@ideasonboard.com>\n\t<20250625155308.2325438-2-dan.scally@ideasonboard.com>\n\t<20250626131027.GP8738@pendragon.ideasonboard.com>","MIME-Version":"1.0","Content-Type":"text/plain; charset=utf-8","Content-Disposition":"inline","In-Reply-To":"<20250626131027.GP8738@pendragon.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":34665,"web_url":"https://patchwork.libcamera.org/comment/34665/","msgid":"<474b7e67-6208-47a8-9821-979f5060c43f@ideasonboard.com>","date":"2025-06-26T13:26:29","subject":"Re: [PATCH v1 1/2] libcamera: device_enumerator: Use regex to match\n\tentity names","submitter":{"id":156,"url":"https://patchwork.libcamera.org/api/people/156/","name":"Dan Scally","email":"dan.scally@ideasonboard.com"},"content":"Hi Laurent\n\nOn 26/06/2025 14:10, Laurent Pinchart wrote:\n> Hi Dan,\n>\n> Thank you for the patch.\n>\n> On Wed, Jun 25, 2025 at 04:53:07PM +0100, Daniel Scally wrote:\n>> Some entities in a media graph have names that might differ from\n>> implementation to implementation; for example the Camera Receiver\n>> Unit and CSI-2 receiver on the KakiP board have entities with names\n>> that include their address, in the form \"csi-16000400.csi2\". Passing\n>> that entity name to DeviceMatch is too inflexible given it would only\n>> work if that specific CSI-2 receiver were the one being used.\n>>\n>> Update DeviceMatch.add() such that the string passed to it is used to\n>> create a std::basic_regex, and use std::regex_search() instead of a\n>> direct string comparison in DeviceMatch::match(). This allows us to\n>> pass a string that will form a regex expression to match to the entity\n>> instead, for example \"csi-[0-9]{8}.csi2\".\n> So you'll only support SoCs whose CSI-2 receiver are mapped to an\n> address that contains no alphabetic digits ? :-)\n\n\nOh yeah...erm, \"csi-[0-9a-fA-F]{8}.csi2\" then?\n\n>\n>> Signed-off-by: Daniel Scally \n>> ---\n>> .../libcamera/internal/device_enumerator.h | 3 ++-\n>> src/libcamera/device_enumerator.cpp | 27 ++++++++++---------\n>> 2 files changed, 16 insertions(+), 14 deletions(-)\n>>\n>> diff --git a/include/libcamera/internal/device_enumerator.h b/include/libcamera/internal/device_enumerator.h\n>> index db3532a9..fce7f0ea 100644\n>> --- a/include/libcamera/internal/device_enumerator.h\n>> +++ b/include/libcamera/internal/device_enumerator.h\n>> @@ -8,6 +8,7 @@\n>> #pragma once\n>> \n>> #include \n>> +#include \n> See commit b01918978c82 (\"libcamera: v4l2_subdevice: Work around false\n> positive warning\").\n\n\nOoh. OK...I guess it's time for a wrapper then...do you mean in your commit message comment that we \nought to create a libcamera::regex class that wraps the std class, with that #pragma guarding the \ninclude in the source file?\n\n>\n>> #include \n>> #include \n>> \n>> @@ -28,7 +29,7 @@ public:\n>> \n>> private:\n>> \tstd::string driver_;\n>> -\tstd::vector entities_;\n>> +\tstd::vector entities_;\n>> };\n>> \n>> class DeviceEnumerator\n>> diff --git a/src/libcamera/device_enumerator.cpp b/src/libcamera/device_enumerator.cpp\n>> index ae17862f..e22d2822 100644\n>> --- a/src/libcamera/device_enumerator.cpp\n>> +++ b/src/libcamera/device_enumerator.cpp\n>> @@ -52,15 +52,15 @@ LOG_DEFINE_CATEGORY(DeviceEnumerator)\n>> * device enumerator to find matching media devices.\n>> *\n>> * A DeviceMatch is created with a specific Linux device driver in mind,\n>> - * therefore the name of the driver is a required property. One or more Entity\n>> - * names can be added as match criteria.\n>> + * therefore the name of the driver is a required property. Regex expressions to\n>> + * match one or more Entity names can be added as match criteria.\n>> *\n>> - * Pipeline handlers are recommended to add entities to DeviceMatch as\n>> - * appropriate to ensure that the media device they need can be uniquely\n>> - * identified. This is useful when the corresponding kernel driver can produce\n>> - * different graphs, for instance as a result of different driver versions or\n>> - * hardware configurations, and not all those graphs are suitable for a pipeline\n>> - * handler.\n>> + * Pipeline handlers are recommended to add regex expressions for entities to\n>> + * DeviceMatch as appropriate to ensure that the media device they need can be\n>> + * uniquely identified. This is useful when the corresponding kernel driver can\n>> + * produce different graphs, for instance as a result of different driver\n>> + * versions or hardware configurations, and not all those graphs are suitable\n>> + * for a pipeline handler.\n>> */\n>> \n>> /**\n>> @@ -73,12 +73,13 @@ DeviceMatch::DeviceMatch(const std::string &driver)\n>> }\n>> \n>> /**\n>> - * \\brief Add a media entity name to the search pattern\n>> - * \\param[in] entity The name of the entity in the media graph\n>> + * \\brief Add a media entity regex string to the search pattern\n>> + * \\param[in] entity A regex string to match the entity in the media graph\n>> */\n>> void DeviceMatch::add(const std::string &entity)\n>> {\n>> -\tentities_.push_back(entity);\n>> +\tstd::regex entity_regex(entity);\n> camelCase. Same below.\n>\n>> +\tentities_.push_back(entity_regex);\n> Construct in-place with emplace_back, don't use a local variable.\n>\n>> }\n>> \n>> /**\n>> @@ -96,11 +97,11 @@ bool DeviceMatch::match(const MediaDevice *device) const\n>> \tif (driver_ != device->driver())\n>> \t\treturn false;\n>> \n>> -\tfor (const std::string &name : entities_) {\n>> +\tfor (const std::regex &name_regex : entities_) {\n>> \t\tbool found = false;\n>> \n>> \t\tfor (const MediaEntity *entity : device->entities()) {\n>> -\t\t\tif (name == entity->name()) {\n>> +\t\t\tif (std::regex_search(entity->name(), name_regex)) {\n>> \t\t\t\tif (!entity->deviceNode().empty()) {\n>> \t\t\t\t\tfound = true;\n>> \t\t\t\t\tbreak;","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 73CE8BDCBF\n\tfor ;\n\tThu, 26 Jun 2025 13:26:35 +0000 (UTC)","from lancelot.ideasonboard.com (localhost [IPv6:::1])\n\tby lancelot.ideasonboard.com (Postfix) with ESMTP id D9C4268DF6;\n\tThu, 26 Jun 2025 15:26:33 +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 9335768DE8\n\tfor ;\n\tThu, 26 Jun 2025 15:26:32 +0200 (CEST)","from [192.168.0.43]\n\t(cpc141996-chfd3-2-0-cust928.12-3.cable.virginm.net [86.13.91.161])\n\tby perceval.ideasonboard.com (Postfix) with ESMTPSA id 6AFD1833;\n\tThu, 26 Jun 2025 15:26:13 +0200 (CEST)"],"Authentication-Results":"lancelot.ideasonboard.com; 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keydata=\n\txsFNBGLydlEBEADa5O2s0AbUguprfvXOQun/0a8y2Vk6BqkQALgeD6KnXSWwaoCULp18etYW\n\tB31bfgrdphXQ5kUQibB0ADK8DERB4wrzrUb5CMxLBFE7mQty+v5NsP0OFNK9XTaAOcmD+Ove\n\teIjYvqurAaro91jrRVrS1gBRxIFqyPgNvwwL+alMZhn3/2jU2uvBmuRrgnc/e9cHKiuT3Dtq\n\tMHGPKL2m+plk+7tjMoQFfexoQ1JKugHAjxAhJfrkXh6uS6rc01bYCyo7ybzg53m1HLFJdNGX\n\tsUKR+dQpBs3SY4s66tc1sREJqdYyTsSZf80HjIeJjU/hRunRo4NjRIJwhvnK1GyjOvvuCKVU\n\tRWpY8dNjNu5OeAfdrlvFJOxIE9M8JuYCQTMULqd1NuzbpFMjc9524U3Cngs589T7qUMPb1H1\n\tNTA81LmtJ6Y+IV5/kiTUANflpzBwhu18Ok7kGyCq2a2jsOcVmk8gZNs04gyjuj8JziYwwLbf\n\tvzABwpFVcS8aR+nHIZV1HtOzyw8CsL8OySc3K9y+Y0NRpziMRvutrppzgyMb9V+N31mK9Mxl\n\t1YkgaTl4ciNWpdfUe0yxH03OCuHi3922qhPLF4XX5LN+NaVw5Xz2o3eeWklXdouxwV7QlN33\n\tu4+u2FWzKxDqO6WLQGjxPE0mVB4Gh5Pa1Vb0ct9Ctg0qElvtGQARAQABzShEYW4gU2NhbGx5\n\tIDxkYW4uc2NhbGx5QGlkZWFzb25ib2FyZC5jb20+wsGNBBMBCAA3FiEEsdtt8OWP7+8SNfQe\n\tkiQuh/L+GMQFAmLydlIFCQWjmoACGwMECwkIBwUVCAkKCwUWAgMBAAAKCRCSJC6H8v4YxDI2\n\tEAC2Gz0iyaXJkPInyshrREEWbo0CA6v5KKf3I/HlMPqkZ48bmGoYm4mEQGFWZJAT3K4ir8bg\n\tcEfs9V54gpbrZvdwS4abXbUK4WjKwEs8HK3XJv1WXUN2bsz5oEJWZUImh9gD3naiLLI9QMMm\n\tw/aZkT+NbN5/2KvChRWhdcha7+2Te4foOY66nIM+pw2FZM6zIkInLLUik2zXOhaZtqdeJZQi\n\tHSPU9xu7TRYN4cvdZAnSpG7gQqmLm5/uGZN1/sB3kHTustQtSXKMaIcD/DMNI3JN/t+RJVS7\n\tc0Jh/ThzTmhHyhxx3DRnDIy7kwMI4CFvmhkVC2uNs9kWsj1DuX5kt8513mvfw2OcX9UnNKmZ\n\tnhNCuF6DxVrL8wjOPuIpiEj3V+K7DFF1Cxw1/yrLs8dYdYh8T8vCY2CHBMsqpESROnTazboh\n\tAiQ2xMN1cyXtX11Qwqm5U3sykpLbx2BcmUUUEAKNsM//Zn81QXKG8vOx0ZdMfnzsCaCzt8f6\n\t9dcDBBI3tJ0BI9ByiocqUoL6759LM8qm18x3FYlxvuOs4wSGPfRVaA4yh0pgI+ModVC2Pu3y\n\tejE/IxeatGqJHh6Y+iJzskdi27uFkRixl7YJZvPJAbEn7kzSi98u/5ReEA8Qhc8KO/B7wprj\n\txjNMZNYd0Eth8+WkixHYj752NT5qshKJXcyUU87BTQRi8nZSARAAx0BJayh1Fhwbf4zoY56x\n\txHEpT6DwdTAYAetd3yiKClLVJadYxOpuqyWa1bdfQWPb+h4MeXbWw/53PBgn7gI2EA7ebIRC\n\tPJJhAIkeym7hHZoxqDQTGDJjxFEL11qF+U3rhWiL2Zt0Pl+zFq0eWYYVNiXjsIS4FI2+4m16\n\ttPbDWZFJnSZ828VGtRDQdhXfx3zyVX21lVx1bX4/OZvIET7sVUufkE4hrbqrrufre7wsjD1t\n\t8MQKSapVrr1RltpzPpScdoxknOSBRwOvpp57pJJe5A0L7+WxJ+vQoQXj0j+5tmIWOAV1qBQp\n\thyoyUk9JpPfntk2EKnZHWaApFp5TcL6c5LhUvV7F6XwOjGPuGlZQCWXee9dr7zym8iR3irWT\n\t+49bIh5PMlqSLXJDYbuyFQHFxoiNdVvvf7etvGfqFYVMPVjipqfEQ38ST2nkzx+KBICz7uwj\n\tJwLBdTXzGFKHQNckGMl7F5QdO/35An/QcxBnHVMXqaSd12tkJmoRVWduwuuoFfkTY5mUV3uX\n\txGj3iVCK4V+ezOYA7c2YolfRCNMTza6vcK/P4tDjjsyBBZrCCzhBvd4VVsnnlZhVaIxoky4K\n\taL+AP+zcQrUZmXmgZjXOLryGnsaeoVrIFyrU6ly90s1y3KLoPsDaTBMtnOdwxPmo1xisH8oL\n\ta/VRgpFBfojLPxMAEQEAAcLBfAQYAQgAJhYhBLHbbfDlj+/vEjX0HpIkLofy/hjEBQJi8nZT\n\tBQkFo5qAAhsMAAoJEJIkLofy/hjEXPcQAMIPNqiWiz/HKu9W4QIf1OMUpKn3YkVIj3p3gvfM\n\tRes4fGX94Ji599uLNrPoxKyaytC4R6BTxVriTJjWK8mbo9jZIRM4vkwkZZ2bu98EweSucxbp\n\tvjESsvMXGgxniqV/RQ/3T7LABYRoIUutARYq58p5HwSP0frF0fdFHYdTa2g7MYZl1ur2JzOC\n\tFHRpGadlNzKDE3fEdoMobxHB3Lm6FDml5GyBAA8+dQYVI0oDwJ3gpZPZ0J5Vx9RbqXe8RDuR\n\tdu90hvCJkq7/tzSQ0GeD3BwXb9/R/A4dVXhaDd91Q1qQXidI+2jwhx8iqiYxbT+DoAUkQRQy\n\txBtoCM1CxH7u45URUgD//fxYr3D4B1SlonA6vdaEdHZOGwECnDpTxecENMbz/Bx7qfrmd901\n\tD+N9SjIwrbVhhSyUXYnSUb8F+9g2RDY42Sk7GcYxIeON4VzKqWM7hpkXZ47pkK0YodO+dRKM\n\tyMcoUWrTK0Uz6UzUGKoJVbxmSW/EJLEGoI5p3NWxWtScEVv8mO49gqQdrRIOheZycDmHnItt\n\t9Qjv00uFhEwv2YfiyGk6iGF2W40s2pH2t6oeuGgmiZ7g6d0MEK8Ql/4zPItvr1c1rpwpXUC1\n\tu1kQWgtnNjFHX3KiYdqjcZeRBiry1X0zY+4Y24wUU0KsEewJwjhmCKAsju1RpdlPg2kC","In-Reply-To":"<20250626131027.GP8738@pendragon.ideasonboard.com>","Content-Type":"text/plain; charset=UTF-8; format=flowed","Content-Transfer-Encoding":"7bit","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":34667,"web_url":"https://patchwork.libcamera.org/comment/34667/","msgid":"<20250626133008.GS8738@pendragon.ideasonboard.com>","date":"2025-06-26T13:30:08","subject":"Re: [PATCH v1 1/2] libcamera: device_enumerator: Use regex to match\n\tentity names","submitter":{"id":2,"url":"https://patchwork.libcamera.org/api/people/2/","name":"Laurent Pinchart","email":"laurent.pinchart@ideasonboard.com"},"content":"On Thu, Jun 26, 2025 at 02:26:29PM +0100, Daniel Scally wrote:\n> On 26/06/2025 14:10, Laurent Pinchart wrote:\n> > On Wed, Jun 25, 2025 at 04:53:07PM +0100, Daniel Scally wrote:\n> >> Some entities in a media graph have names that might differ from\n> >> implementation to implementation; for example the Camera Receiver\n> >> Unit and CSI-2 receiver on the KakiP board have entities with names\n> >> that include their address, in the form \"csi-16000400.csi2\". Passing\n> >> that entity name to DeviceMatch is too inflexible given it would only\n> >> work if that specific CSI-2 receiver were the one being used.\n> >>\n> >> Update DeviceMatch.add() such that the string passed to it is used to\n> >> create a std::basic_regex, and use std::regex_search() instead of a\n> >> direct string comparison in DeviceMatch::match(). This allows us to\n> >> pass a string that will form a regex expression to match to the entity\n> >> instead, for example \"csi-[0-9]{8}.csi2\".\n> >\n> > So you'll only support SoCs whose CSI-2 receiver are mapped to an\n> > address that contains no alphabetic digits ? :-)\n> \n> Oh yeah...erm, \"csi-[0-9a-fA-F]{8}.csi2\" then?\n\nI would have hoped the kernel would only use lowercase hex values.\n\n> >> Signed-off-by: Daniel Scally \n> >> ---\n> >> .../libcamera/internal/device_enumerator.h | 3 ++-\n> >> src/libcamera/device_enumerator.cpp | 27 ++++++++++---------\n> >> 2 files changed, 16 insertions(+), 14 deletions(-)\n> >>\n> >> diff --git a/include/libcamera/internal/device_enumerator.h b/include/libcamera/internal/device_enumerator.h\n> >> index db3532a9..fce7f0ea 100644\n> >> --- a/include/libcamera/internal/device_enumerator.h\n> >> +++ b/include/libcamera/internal/device_enumerator.h\n> >> @@ -8,6 +8,7 @@\n> >> #pragma once\n> >> \n> >> #include \n> >> +#include \n> >\n> > See commit b01918978c82 (\"libcamera: v4l2_subdevice: Work around false\n> > positive warning\").\n> \n> Ooh. OK...I guess it's time for a wrapper then...do you mean in your commit message comment that we \n> ought to create a libcamera::regex class that wraps the std class, with that #pragma guarding the \n> include in the source file?\n\nI think a libcamera/base/regex.h file that wraps regex is enough, no\nneed for a class.\n\n> >> #include \n> >> #include \n> >> \n> >> @@ -28,7 +29,7 @@ public:\n> >> \n> >> private:\n> >> \tstd::string driver_;\n> >> -\tstd::vector entities_;\n> >> +\tstd::vector entities_;\n> >> };\n> >> \n> >> class DeviceEnumerator\n> >> diff --git a/src/libcamera/device_enumerator.cpp b/src/libcamera/device_enumerator.cpp\n> >> index ae17862f..e22d2822 100644\n> >> --- a/src/libcamera/device_enumerator.cpp\n> >> +++ b/src/libcamera/device_enumerator.cpp\n> >> @@ -52,15 +52,15 @@ LOG_DEFINE_CATEGORY(DeviceEnumerator)\n> >> * device enumerator to find matching media devices.\n> >> *\n> >> * A DeviceMatch is created with a specific Linux device driver in mind,\n> >> - * therefore the name of the driver is a required property. One or more Entity\n> >> - * names can be added as match criteria.\n> >> + * therefore the name of the driver is a required property. Regex expressions to\n> >> + * match one or more Entity names can be added as match criteria.\n> >> *\n> >> - * Pipeline handlers are recommended to add entities to DeviceMatch as\n> >> - * appropriate to ensure that the media device they need can be uniquely\n> >> - * identified. This is useful when the corresponding kernel driver can produce\n> >> - * different graphs, for instance as a result of different driver versions or\n> >> - * hardware configurations, and not all those graphs are suitable for a pipeline\n> >> - * handler.\n> >> + * Pipeline handlers are recommended to add regex expressions for entities to\n> >> + * DeviceMatch as appropriate to ensure that the media device they need can be\n> >> + * uniquely identified. This is useful when the corresponding kernel driver can\n> >> + * produce different graphs, for instance as a result of different driver\n> >> + * versions or hardware configurations, and not all those graphs are suitable\n> >> + * for a pipeline handler.\n> >> */\n> >> \n> >> /**\n> >> @@ -73,12 +73,13 @@ DeviceMatch::DeviceMatch(const std::string &driver)\n> >> }\n> >> \n> >> /**\n> >> - * \\brief Add a media entity name to the search pattern\n> >> - * \\param[in] entity The name of the entity in the media graph\n> >> + * \\brief Add a media entity regex string to the search pattern\n> >> + * \\param[in] entity A regex string to match the entity in the media graph\n> >> */\n> >> void DeviceMatch::add(const std::string &entity)\n> >> {\n> >> -\tentities_.push_back(entity);\n> >> +\tstd::regex entity_regex(entity);\n> >\n> > camelCase. Same below.\n> >\n> >> +\tentities_.push_back(entity_regex);\n> >\n> > Construct in-place with emplace_back, don't use a local variable.\n> >\n> >> }\n> >> \n> >> /**\n> >> @@ -96,11 +97,11 @@ bool DeviceMatch::match(const MediaDevice *device) const\n> >> \tif (driver_ != device->driver())\n> >> \t\treturn false;\n> >> \n> >> -\tfor (const std::string &name : entities_) {\n> >> +\tfor (const std::regex &name_regex : entities_) {\n> >> \t\tbool found = false;\n> >> \n> >> \t\tfor (const MediaEntity *entity : device->entities()) {\n> >> -\t\t\tif (name == entity->name()) {\n> >> +\t\t\tif (std::regex_search(entity->name(), name_regex)) {\n> >> \t\t\t\tif (!entity->deviceNode().empty()) {\n> >> \t\t\t\t\tfound = true;\n> >> \t\t\t\t\tbreak;","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 501EAC3237\n\tfor ;\n\tThu, 26 Jun 2025 13:30:34 +0000 (UTC)","from lancelot.ideasonboard.com (localhost [IPv6:::1])\n\tby lancelot.ideasonboard.com (Postfix) with ESMTP id 043C268DF6;\n\tThu, 26 Jun 2025 15:30:34 +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 3590868DE8\n\tfor ;\n\tThu, 26 Jun 2025 15:30:32 +0200 (CEST)","from pendragon.ideasonboard.com (85-76-34-12-nat.elisa-mobile.fi\n\t[85.76.34.12])\n\tby perceval.ideasonboard.com (Postfix) with UTF8SMTPSA id 1A971833;\n\tThu, 26 Jun 2025 15:30:12 +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=\"Meks3ZCp\"; dkim-atps=neutral","DKIM-Signature":"v=1; a=rsa-sha256; c=relaxed/simple; d=ideasonboard.com;\n\ts=mail; t=1750944613;\n\tbh=EwuiAJmer36Yi0LBvo/aoXOQGiYlZQLKj/k/OdfqR24=;\n\th=Date:From:To:Cc:Subject:References:In-Reply-To:From;\n\tb=Meks3ZCpVhw2FcWrxfvL4Oo5iGSLITa93UjI43VQLy4ClAAWEm9wgjyTkWtn2GpC5\n\tWoQDr9FPx1eHKRObJKJLPaFa2YSshiKTfNkX0cQhmz/EJT2OvXDRV8aw9RBqWQ5Sk/\n\tai6jHi1l+1SjsqAARiGUvgo+L46DqRr7jEFTQ/8Q=","Date":"Thu, 26 Jun 2025 16:30:08 +0300","From":"Laurent Pinchart ","To":"Dan Scally ","Cc":"libcamera-devel@lists.libcamera.org","Subject":"Re: [PATCH v1 1/2] libcamera: device_enumerator: Use regex to match\n\tentity names","Message-ID":"<20250626133008.GS8738@pendragon.ideasonboard.com>","References":"<20250625155308.2325438-1-dan.scally@ideasonboard.com>\n\t<20250625155308.2325438-2-dan.scally@ideasonboard.com>\n\t<20250626131027.GP8738@pendragon.ideasonboard.com>\n\t<474b7e67-6208-47a8-9821-979f5060c43f@ideasonboard.com>","MIME-Version":"1.0","Content-Type":"text/plain; charset=utf-8","Content-Disposition":"inline","In-Reply-To":"<474b7e67-6208-47a8-9821-979f5060c43f@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":34903,"web_url":"https://patchwork.libcamera.org/comment/34903/","msgid":"<4b7a1d6f-5f65-455d-baa9-3c87f4a196db@ideasonboard.com>","date":"2025-07-15T14:17:48","subject":"Re: [PATCH v1 1/2] libcamera: device_enumerator: Use regex to match\n\tentity names","submitter":{"id":156,"url":"https://patchwork.libcamera.org/api/people/156/","name":"Dan Scally","email":"dan.scally@ideasonboard.com"},"content":"Hi Laurent\n\nOn 26/06/2025 14:11, Laurent Pinchart wrote:\n> On Thu, Jun 26, 2025 at 04:10:31PM +0300, Laurent Pinchart wrote:\n>> Hi Dan,\n>>\n>> Thank you for the patch.\n>>\n>> On Wed, Jun 25, 2025 at 04:53:07PM +0100, Daniel Scally wrote:\n>>> Some entities in a media graph have names that might differ from\n>>> implementation to implementation; for example the Camera Receiver\n>>> Unit and CSI-2 receiver on the KakiP board have entities with names\n>>> that include their address, in the form \"csi-16000400.csi2\". Passing\n>>> that entity name to DeviceMatch is too inflexible given it would only\n>>> work if that specific CSI-2 receiver were the one being used.\n>>>\n>>> Update DeviceMatch.add() such that the string passed to it is used to\n>>> create a std::basic_regex, and use std::regex_search() instead of a\n>>> direct string comparison in DeviceMatch::match(). This allows us to\n>>> pass a string that will form a regex expression to match to the entity\n>>> instead, for example \"csi-[0-9]{8}.csi2\".\n>> So you'll only support SoCs whose CSI-2 receiver are mapped to an\n>> address that contains no alphabetic digits ? :-)\n> Also note that the '.' in the regex can now match any character. Do we\n> need to update all users of DeviceMatch to escape '.' ?\n\n\nAh; damn, of course it does...that's horrible. In that case I think we can either update all the \nusers or else extend this change to differentiate between an exact match method and a regex match \nmethod - I think that that's probably the better approach.\n\n>\n>>> Signed-off-by: Daniel Scally \n>>> ---\n>>> .../libcamera/internal/device_enumerator.h | 3 ++-\n>>> src/libcamera/device_enumerator.cpp | 27 ++++++++++---------\n>>> 2 files changed, 16 insertions(+), 14 deletions(-)\n>>>\n>>> diff --git a/include/libcamera/internal/device_enumerator.h b/include/libcamera/internal/device_enumerator.h\n>>> index db3532a9..fce7f0ea 100644\n>>> --- a/include/libcamera/internal/device_enumerator.h\n>>> +++ b/include/libcamera/internal/device_enumerator.h\n>>> @@ -8,6 +8,7 @@\n>>> #pragma once\n>>> \n>>> #include \n>>> +#include \n>> See commit b01918978c82 (\"libcamera: v4l2_subdevice: Work around false\n>> positive warning\").\n>>\n>>> #include \n>>> #include \n>>> \n>>> @@ -28,7 +29,7 @@ public:\n>>> \n>>> private:\n>>> \tstd::string driver_;\n>>> -\tstd::vector entities_;\n>>> +\tstd::vector entities_;\n>>> };\n>>> \n>>> class DeviceEnumerator\n>>> diff --git a/src/libcamera/device_enumerator.cpp b/src/libcamera/device_enumerator.cpp\n>>> index ae17862f..e22d2822 100644\n>>> --- a/src/libcamera/device_enumerator.cpp\n>>> +++ b/src/libcamera/device_enumerator.cpp\n>>> @@ -52,15 +52,15 @@ LOG_DEFINE_CATEGORY(DeviceEnumerator)\n>>> * device enumerator to find matching media devices.\n>>> *\n>>> * A DeviceMatch is created with a specific Linux device driver in mind,\n>>> - * therefore the name of the driver is a required property. One or more Entity\n>>> - * names can be added as match criteria.\n>>> + * therefore the name of the driver is a required property. Regex expressions to\n>>> + * match one or more Entity names can be added as match criteria.\n>>> *\n>>> - * Pipeline handlers are recommended to add entities to DeviceMatch as\n>>> - * appropriate to ensure that the media device they need can be uniquely\n>>> - * identified. This is useful when the corresponding kernel driver can produce\n>>> - * different graphs, for instance as a result of different driver versions or\n>>> - * hardware configurations, and not all those graphs are suitable for a pipeline\n>>> - * handler.\n>>> + * Pipeline handlers are recommended to add regex expressions for entities to\n>>> + * DeviceMatch as appropriate to ensure that the media device they need can be\n>>> + * uniquely identified. This is useful when the corresponding kernel driver can\n>>> + * produce different graphs, for instance as a result of different driver\n>>> + * versions or hardware configurations, and not all those graphs are suitable\n>>> + * for a pipeline handler.\n>>> */\n>>> \n>>> /**\n>>> @@ -73,12 +73,13 @@ DeviceMatch::DeviceMatch(const std::string &driver)\n>>> }\n>>> \n>>> /**\n>>> - * \\brief Add a media entity name to the search pattern\n>>> - * \\param[in] entity The name of the entity in the media graph\n>>> + * \\brief Add a media entity regex string to the search pattern\n>>> + * \\param[in] entity A regex string to match the entity in the media graph\n>>> */\n>>> void DeviceMatch::add(const std::string &entity)\n>>> {\n>>> -\tentities_.push_back(entity);\n>>> +\tstd::regex entity_regex(entity);\n>> camelCase. Same below.\n>>\n>>> +\tentities_.push_back(entity_regex);\n>> Construct in-place with emplace_back, don't use a local variable.\n>>\n>>> }\n>>> \n>>> /**\n>>> @@ -96,11 +97,11 @@ bool DeviceMatch::match(const MediaDevice *device) const\n>>> \tif (driver_ != device->driver())\n>>> \t\treturn false;\n>>> \n>>> -\tfor (const std::string &name : entities_) {\n>>> +\tfor (const std::regex &name_regex : entities_) {\n>>> \t\tbool found = false;\n>>> \n>>> \t\tfor (const MediaEntity *entity : device->entities()) {\n>>> -\t\t\tif (name == entity->name()) {\n>>> +\t\t\tif (std::regex_search(entity->name(), name_regex)) {\n>>> \t\t\t\tif (!entity->deviceNode().empty()) {\n>>> \t\t\t\t\tfound = true;\n>>> \t\t\t\t\tbreak;\n>> -- \n>> Regards,\n>>\n>> Laurent Pinchart","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 928CCC3237\n\tfor ;\n\tTue, 15 Jul 2025 14:17:54 +0000 (UTC)","from lancelot.ideasonboard.com (localhost [IPv6:::1])\n\tby lancelot.ideasonboard.com (Postfix) with ESMTP id 7D5606186B;\n\tTue, 15 Jul 2025 16:17:53 +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 02A276186B\n\tfor ;\n\tTue, 15 Jul 2025 16:17:51 +0200 (CEST)","from [192.168.0.43]\n\t(cpc141996-chfd3-2-0-cust928.12-3.cable.virginm.net [86.13.91.161])\n\tby perceval.ideasonboard.com (Postfix) with ESMTPSA id 5E86A78E;\n\tTue, 15 Jul 2025 16:17:19 +0200 (CEST)"],"Authentication-Results":"lancelot.ideasonboard.com; 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