{"id":23393,"url":"https://patchwork.libcamera.org/api/patches/23393/?format=json","web_url":"https://patchwork.libcamera.org/patch/23393/","project":{"id":1,"url":"https://patchwork.libcamera.org/api/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":"<20250519122352.1675360-2-julien.vuillaumier@nxp.com>","date":"2025-05-19T12:23:52","name":"[v3,1/1] libcamera: process: Pass stderr and reserve stdin and stdout fds","commit_ref":null,"pull_url":null,"state":"accepted","archived":false,"hash":"6acd4fdb23762632c45d8b5760a5e4025c0901c4","submitter":{"id":190,"url":"https://patchwork.libcamera.org/api/people/190/?format=json","name":"Julien Vuillaumier","email":"julien.vuillaumier@nxp.com"},"delegate":null,"mbox":"https://patchwork.libcamera.org/patch/23393/mbox/","series":[{"id":5183,"url":"https://patchwork.libcamera.org/api/series/5183/?format=json","web_url":"https://patchwork.libcamera.org/project/libcamera/list/?series=5183","date":"2025-05-19T12:23:51","name":"libcamera: process: Pass stderr and reserve stdin and stdout fds","version":3,"mbox":"https://patchwork.libcamera.org/series/5183/mbox/"}],"comments":"https://patchwork.libcamera.org/api/patches/23393/comments/","check":"pending","checks":"https://patchwork.libcamera.org/api/patches/23393/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 CEA0DBD78E\n\tfor ;\n\tMon, 19 May 2025 12:24:37 +0000 (UTC)","from lancelot.ideasonboard.com (localhost [IPv6:::1])\n\tby lancelot.ideasonboard.com (Postfix) with ESMTP id 7F76468D79;\n\tMon, 19 May 2025 14:24:37 +0200 (CEST)","from EUR05-AM6-obe.outbound.protection.outlook.com\n\t(mail-am6eur05on20613.outbound.protection.outlook.com\n\t[IPv6:2a01:111:f403:2612::613])\n\tby lancelot.ideasonboard.com (Postfix) with ESMTPS id 6253368B6C\n\tfor ;\n\tMon, 19 May 2025 14:24:35 +0200 (CEST)","from AM9PR04MB8147.eurprd04.prod.outlook.com\n\t(2603:10a6:20b:3e0::22)\n\tby AM9PR04MB7489.eurprd04.prod.outlook.com (2603:10a6:20b:281::15)\n\twith Microsoft SMTP Server (version=TLS1_2,\n\tcipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.20.8746.30;\n\tMon, 19 May 2025 12:24:34 +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\tMon, 19 May 2025 12:24:33 +0000"],"Authentication-Results":["lancelot.ideasonboard.com; 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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 \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 68fad327..fa92f58c 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 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\texit(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":["v3","1/1"]}