{"id":14883,"url":"https://patchwork.libcamera.org/api/1.1/patches/14883/?format=json","web_url":"https://patchwork.libcamera.org/patch/14883/","project":{"id":1,"url":"https://patchwork.libcamera.org/api/1.1/projects/1/?format=json","name":"libcamera","link_name":"libcamera","list_id":"libcamera_core","list_email":"libcamera-devel@lists.libcamera.org","web_url":"","scm_url":"","webscm_url":""},"msgid":"<20211130102736.1768-1-laurent.pinchart@ideasonboard.com>","date":"2021-11-30T10:27:36","name":"[libcamera-devel,v4.1,07/22] libcamera: base: file_descriptor: Return UniqueFD from dup()","commit_ref":null,"pull_url":null,"state":"accepted","archived":false,"hash":"a388d182c02786200a9661a725785d905b7919d6","submitter":{"id":2,"url":"https://patchwork.libcamera.org/api/1.1/people/2/?format=json","name":"Laurent Pinchart","email":"laurent.pinchart@ideasonboard.com"},"delegate":null,"mbox":"https://patchwork.libcamera.org/patch/14883/mbox/","series":[{"id":2781,"url":"https://patchwork.libcamera.org/api/1.1/series/2781/?format=json","web_url":"https://patchwork.libcamera.org/project/libcamera/list/?series=2781","date":"2021-11-30T10:27:16","name":null,"version":1,"mbox":"https://patchwork.libcamera.org/series/2781/mbox/"}],"comments":"https://patchwork.libcamera.org/api/patches/14883/comments/","check":"pending","checks":"https://patchwork.libcamera.org/api/patches/14883/checks/","tags":{},"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 A0E2ABF415\n\tfor ;\n\tTue, 30 Nov 2021 10:28:05 +0000 (UTC)","from lancelot.ideasonboard.com (localhost [IPv6:::1])\n\tby lancelot.ideasonboard.com (Postfix) with ESMTP id 5783E605B4;\n\tTue, 30 Nov 2021 11:28:05 +0100 (CET)","from perceval.ideasonboard.com (perceval.ideasonboard.com\n\t[213.167.242.64])\n\tby lancelot.ideasonboard.com (Postfix) with ESMTPS id D1A9160230\n\tfor ;\n\tTue, 30 Nov 2021 11:28:03 +0100 (CET)","from pendragon.lan (62-78-145-57.bb.dnainternet.fi [62.78.145.57])\n\tby perceval.ideasonboard.com (Postfix) with ESMTPSA id 6F7732A5\n\tfor ;\n\tTue, 30 Nov 2021 11:28:03 +0100 (CET)"],"Authentication-Results":"lancelot.ideasonboard.com;\n\tdkim=fail reason=\"signature verification failed\" (1024-bit key;\n\tunprotected) header.d=ideasonboard.com header.i=@ideasonboard.com\n\theader.b=\"d65vqPik\"; dkim-atps=neutral","DKIM-Signature":"v=1; a=rsa-sha256; c=relaxed/simple; d=ideasonboard.com;\n\ts=mail; t=1638268083;\n\tbh=YSFQHGBQvSj8ibJm0RrAidBpqucwCNeGQQw1uH3Hscc=;\n\th=From:To:Subject:Date:In-Reply-To:References:From;\n\tb=d65vqPik1HZiYxEuesc3WkHlDDrjfKHazKwiOyCls4MLsjg6a3VOj+OEVV93gRi4s\n\tc2MLhusngs4LwZunDVN1dEtwo+IBW66FciKwZkynsE8/96xiVYdAX5HeG04pycCae/\n\tPyuEZwBKy6yEimcsXANkHd1WlV3MaffiCZM9H+EU=","From":"Laurent Pinchart ","To":"libcamera-devel@lists.libcamera.org","Date":"Tue, 30 Nov 2021 12:27:36 +0200","Message-Id":"<20211130102736.1768-1-laurent.pinchart@ideasonboard.com>","X-Mailer":"git-send-email 2.32.0","In-Reply-To":"<20211130033820.18235-8-laurent.pinchart@ideasonboard.com>","References":"<20211130033820.18235-8-laurent.pinchart@ideasonboard.com>","MIME-Version":"1.0","Content-Transfer-Encoding":"8bit","Subject":"[libcamera-devel] [PATCH v4.1 07/22] libcamera: base:\n\tfile_descriptor: Return UniqueFD from dup()","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\" "},"content":"The dup() function returns a duplicate of the file descriptor. Wrapping\nit in a FileDescriptor isn't wrong as such, but it prevents from using\nit in contexts where a UniqueFD is needed. As the duplicate is\nguaranteed to have a single owner when created, return it as a UniqueFD\ninstead. A FileDescriptor can easily be created from the UniqueFD if\ndesired.\n\nSigned-off-by: Laurent Pinchart \nReviewed-by: Hirokazu Honda \nReviewed-by: Jacopo Mondi \n---\nChanges since v4:\n\n- Store ::dup() return value directly in UniqueFD\n---\n include/libcamera/base/file_descriptor.h | 2 +-\n src/libcamera/base/file_descriptor.cpp | 22 ++++++++++++++--------\n 2 files changed, 15 insertions(+), 9 deletions(-)","diff":"diff --git a/include/libcamera/base/file_descriptor.h b/include/libcamera/base/file_descriptor.h\nindex 74292eba04f5..12a43f95d414 100644\n--- a/include/libcamera/base/file_descriptor.h\n+++ b/include/libcamera/base/file_descriptor.h\n@@ -28,7 +28,7 @@ public:\n \n \tbool isValid() const { return fd_ != nullptr; }\n \tint fd() const { return fd_ ? fd_->fd() : -1; }\n-\tFileDescriptor dup() const;\n+\tUniqueFD dup() const;\n \n private:\n \tclass Descriptor\ndiff --git a/src/libcamera/base/file_descriptor.cpp b/src/libcamera/base/file_descriptor.cpp\nindex da696b2501cd..8e181abc44bb 100644\n--- a/src/libcamera/base/file_descriptor.cpp\n+++ b/src/libcamera/base/file_descriptor.cpp\n@@ -222,17 +222,23 @@ FileDescriptor &FileDescriptor::operator=(FileDescriptor &&other)\n * \\brief Duplicate a FileDescriptor\n *\n * Duplicating a FileDescriptor creates a duplicate of the wrapped file\n- * descriptor and returns a new FileDescriptor instance that wraps the\n- * duplicate. The fd() function of the original and duplicate instances will\n- * return different values. The duplicate instance will not be affected by\n- * destruction of the original instance or its copies.\n+ * descriptor and returns a UniqueFD that owns the duplicate. The fd() function\n+ * of the original and the get() function of the duplicate will return different\n+ * values. The duplicate instance will not be affected by destruction of the\n+ * original instance or its copies.\n *\n- * \\return A new FileDescriptor instance wrapping a duplicate of the original\n- * file descriptor\n+ * \\return A UniqueFD owning a duplicate of the original file descriptor\n */\n-FileDescriptor FileDescriptor::dup() const\n+UniqueFD FileDescriptor::dup() const\n {\n-\treturn FileDescriptor(fd());\n+\tUniqueFD dupFd(::dup(fd()));\n+\tif (!dupFd.isValid()) {\n+\t\tint ret = -errno;\n+\t\tLOG(FileDescriptor, Error)\n+\t\t\t<< \"Failed to dup() fd: \" << strerror(-ret);\n+\t}\n+\n+\treturn dupFd;\n }\n \n FileDescriptor::Descriptor::Descriptor(int fd, bool duplicate)\n","prefixes":["libcamera-devel","v4.1","07/22"]}