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{ "id": 23453, "url": "https://patchwork.libcamera.org/api/patches/23453/?format=api", "web_url": "https://patchwork.libcamera.org/patch/23453/", "project": { "id": 1, "url": "https://patchwork.libcamera.org/api/projects/1/?format=api", "name": "libcamera", "link_name": "libcamera", "list_id": "libcamera_core", "list_email": "libcamera-devel@lists.libcamera.org", "web_url": "", "scm_url": "", "webscm_url": "" }, "msgid": "<20250527155615.560463-3-julien.vuillaumier@nxp.com>", "date": "2025-05-27T15:56:15", "name": "[v4,2/2] libcamera: process: Pass stderr and reserve stdin and stdout fds", "commit_ref": "5b7c83d8ccd45f5ff533e6bed2001260c765dbb9", "pull_url": null, "state": "accepted", "archived": false, "hash": "1fbe259c354b7cdae2d92a0a8b948412b66497e3", "submitter": { "id": 190, "url": "https://patchwork.libcamera.org/api/people/190/?format=api", "name": "Julien Vuillaumier", "email": "julien.vuillaumier@nxp.com" }, "delegate": null, "mbox": "https://patchwork.libcamera.org/patch/23453/mbox/", "series": [ { "id": 5198, "url": "https://patchwork.libcamera.org/api/series/5198/?format=api", "web_url": "https://patchwork.libcamera.org/project/libcamera/list/?series=5198", "date": "2025-05-27T15:56:13", "name": "libcamera: process: Pass stderr and reserve stdin and stdout fds", "version": 4, "mbox": "https://patchwork.libcamera.org/series/5198/mbox/" } ], "comments": "https://patchwork.libcamera.org/api/patches/23453/comments/", "check": "pending", "checks": "https://patchwork.libcamera.org/api/patches/23453/checks/", "tags": {}, "headers": { "Return-Path": "<libcamera-devel-bounces@lists.libcamera.org>", "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 B39A1C3237\n\tfor <parsemail@patchwork.libcamera.org>;\n\tTue, 27 May 2025 15:57:19 +0000 (UTC)", "from lancelot.ideasonboard.com (localhost [IPv6:::1])\n\tby lancelot.ideasonboard.com (Postfix) with ESMTP id 6DD3668DA5;\n\tTue, 27 May 2025 17:57:19 +0200 (CEST)", "from DU2PR03CU002.outbound.protection.outlook.com\n\t(mail-northeuropeazlp170110003.outbound.protection.outlook.com\n\t[IPv6:2a01:111:f403:c200::3])\n\tby lancelot.ideasonboard.com (Postfix) with ESMTPS id 9EAFF68D94\n\tfor <libcamera-devel@lists.libcamera.org>;\n\tTue, 27 May 2025 17:57:17 +0200 (CEST)", "from AM9PR04MB8147.eurprd04.prod.outlook.com\n\t(2603:10a6:20b:3e0::22)\n\tby AS8PR04MB8499.eurprd04.prod.outlook.com (2603:10a6:20b:342::15)\n\twith Microsoft SMTP Server (version=TLS1_2,\n\tcipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.20.8769.29;\n\tTue, 27 May 2025 15:57:16 +0000", "from AM9PR04MB8147.eurprd04.prod.outlook.com\n\t([fe80::eace:e980:28a4:ef8a]) by\n\tAM9PR04MB8147.eurprd04.prod.outlook.com\n\t([fe80::eace:e980:28a4:ef8a%7]) with mapi id 15.20.8722.027;\n\tTue, 27 May 2025 15:57:16 +0000" ], "Authentication-Results": [ "lancelot.ideasonboard.com; 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mx.microsoft.com 1; spf=pass\n\tsmtp.mailfrom=nxp.com; dmarc=pass action=none header.from=nxp.com;\n\tdkim=pass header.d=nxp.com; arc=none", "DKIM-Signature": "v=1; a=rsa-sha256; c=relaxed/relaxed; d=nxp.com; s=selector1;\n\th=From:Date:Subject:Message-ID:Content-Type:MIME-Version:X-MS-Exchange-SenderADCheck;\n\tbh=76OcfOe2+3qaMfVCbJSFj5zGUnpKmw24YivdielJyOE=;\n\tb=RecLk4GKRdXPYQunr3KCsjURDNUTXJbqOc4Mx5clz/BPHYr4Rp6X3qjge50fH9doATPRWibBgILP82a15fFc6x/URNWfgrvAaYAxOpAChDHyMp5NFkvH0rwJLW0ua8vpME2IgwtHTYLwAe7WeSONm3FeqfNqB2UeAtlFD04xh7ppadXvnk3bAjxAm+SCCDwwWUHOhbVH5nWgcM1WOTVEwzMYjP45fcOfhQAG6ZwEc9E5r9ikzkPZkp3/3kFRPAk8eZP4JpbOqiEKQ30pfsMYgtrK41R5jxhES8hfVuhu75Ef/ITc+Om7hZPFky/q9VUSsEvKo0Ck4bllCLvSZD4TNQ==", "From": "Julien Vuillaumier <julien.vuillaumier@nxp.com>", "To": "libcamera-devel@lists.libcamera.org, barnabas.pocze@ideasonboard.com,\n\tpaul.elder@ideasonboard.com", "Cc": "Julien Vuillaumier <julien.vuillaumier@nxp.com>", "Subject": "[PATCH v4 2/2] libcamera: process: Pass stderr and reserve stdin and\n\tstdout fds", "Date": "Tue, 27 May 2025 17:56:15 +0200", "Message-Id": "<20250527155615.560463-3-julien.vuillaumier@nxp.com>", "X-Mailer": "git-send-email 2.34.1", "In-Reply-To": "<20250527155615.560463-1-julien.vuillaumier@nxp.com>", "References": "<20250527155615.560463-1-julien.vuillaumier@nxp.com>", "Content-Transfer-Encoding": "8bit", "Content-Type": "text/plain", "X-ClientProxiedBy": "AS4PR09CA0017.eurprd09.prod.outlook.com\n\t(2603:10a6:20b:5d4::11) To AM9PR04MB8147.eurprd04.prod.outlook.com\n\t(2603:10a6:20b:3e0::22)", "MIME-Version": "1.0", "X-MS-PublicTrafficType": "Email", "X-MS-TrafficTypeDiagnostic": "AM9PR04MB8147:EE_|AS8PR04MB8499:EE_", "X-MS-Office365-Filtering-Correlation-Id": "8b575084-e1dc-4cc2-4416-08dd9d372743", "X-MS-Exchange-SenderADCheck": "1", "X-MS-Exchange-AntiSpam-Relay": "0", "X-Microsoft-Antispam": "BCL:0;\n\tARA:13230040|1800799024|366016|376014|52116014|38350700014; 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That is to prevent those descriptors\nto be reused for any other resource, that could be corrupted by\nthe presence of printf(), assert() or alike.\n\nSigned-off-by: Julien Vuillaumier <julien.vuillaumier@nxp.com>\nReviewed-by: Paul Elder <paul.elder@ideasonboard.com>\n---\n src/libcamera/process.cpp | 16 +++++++++++++++-\n 1 file changed, 15 insertions(+), 1 deletion(-)", "diff": "diff --git a/src/libcamera/process.cpp b/src/libcamera/process.cpp\nindex 7f3a6518..d836fb07 100644\n--- a/src/libcamera/process.cpp\n+++ b/src/libcamera/process.cpp\n@@ -259,7 +259,21 @@ int Process::start(const std::string &path,\n \t\tif (isolate())\n \t\t\t_exit(EXIT_FAILURE);\n \n-\t\tcloseAllFdsExcept(fds);\n+\t\tstd::vector<int> v(fds);\n+\t\tv.push_back(STDERR_FILENO);\n+\t\tcloseAllFdsExcept(v);\n+\n+\t\tconst auto tryDevNullLowestFd = [](int expected, int oflag) {\n+\t\t\tint fd = open(\"/dev/null\", oflag);\n+\t\t\tif (fd < 0)\n+\t\t\t\t_exit(EXIT_FAILURE);\n+\t\t\tif (fd != expected)\n+\t\t\t\tclose(fd);\n+\t\t};\n+\n+\t\ttryDevNullLowestFd(STDIN_FILENO, O_RDONLY);\n+\t\ttryDevNullLowestFd(STDOUT_FILENO, O_WRONLY);\n+\t\ttryDevNullLowestFd(STDERR_FILENO, O_WRONLY);\n \n \t\tconst char *file = utils::secure_getenv(\"LIBCAMERA_LOG_FILE\");\n \t\tif (file && strcmp(file, \"syslog\"))\n", "prefixes": [ "v4", "2/2" ] }