{"id":9208,"url":"https://patchwork.libcamera.org/api/patches/9208/?format=json","web_url":"https://patchwork.libcamera.org/patch/9208/","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":"<20200805104900.2172763-2-niklas.soderlund@ragnatech.se>","date":"2020-08-05T10:48:52","name":"[libcamera-devel,v8,1/9] libcamera: sysfs: Add helper to lookup sysfs path of a character device","commit_ref":null,"pull_url":null,"state":"accepted","archived":false,"hash":"5f47ba1f9e12348853c15f28629e50871cdd4e3c","submitter":{"id":5,"url":"https://patchwork.libcamera.org/api/people/5/?format=json","name":"Niklas Söderlund","email":"niklas.soderlund@ragnatech.se"},"delegate":null,"mbox":"https://patchwork.libcamera.org/patch/9208/mbox/","series":[{"id":1192,"url":"https://patchwork.libcamera.org/api/series/1192/?format=json","web_url":"https://patchwork.libcamera.org/project/libcamera/list/?series=1192","date":"2020-08-05T10:48:51","name":"libcamera: Generate unique and stable camera IDs","version":8,"mbox":"https://patchwork.libcamera.org/series/1192/mbox/"}],"comments":"https://patchwork.libcamera.org/api/patches/9208/comments/","check":"pending","checks":"https://patchwork.libcamera.org/api/patches/9208/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 BDBC2BD86F\n\tfor ;\n\tWed, 5 Aug 2020 10:49:13 +0000 (UTC)","from lancelot.ideasonboard.com (localhost [IPv6:::1])\n\tby lancelot.ideasonboard.com (Postfix) with ESMTP id 809F460595;\n\tWed, 5 Aug 2020 12:49:13 +0200 (CEST)","from bin-mail-out-05.binero.net (bin-mail-out-05.binero.net\n\t[195.74.38.228])\n\tby lancelot.ideasonboard.com (Postfix) with ESMTPS id D4BF660492\n\tfor ;\n\tWed, 5 Aug 2020 12:49:11 +0200 (CEST)","from bismarck.berto.se (p54ac52a8.dip0.t-ipconnect.de\n\t[84.172.82.168]) by bin-vsp-out-02.atm.binero.net (Halon) with ESMTPA\n\tid 4b0c393e-d709-11ea-a39b-005056917f90;\n\tWed, 05 Aug 2020 12:49:10 +0200 (CEST)"],"X-Halon-ID":"4b0c393e-d709-11ea-a39b-005056917f90","Authorized-sender":"niklas@soderlund.pp.se","From":"=?utf-8?q?Niklas_S=C3=B6derlund?= ","To":"libcamera-devel@lists.libcamera.org","Date":"Wed, 5 Aug 2020 12:48:52 +0200","Message-Id":"<20200805104900.2172763-2-niklas.soderlund@ragnatech.se>","X-Mailer":"git-send-email 2.28.0","In-Reply-To":"<20200805104900.2172763-1-niklas.soderlund@ragnatech.se>","References":"<20200805104900.2172763-1-niklas.soderlund@ragnatech.se>","MIME-Version":"1.0","Subject":"[libcamera-devel] [PATCH v8 1/9] libcamera: sysfs: Add helper to\n\tlookup sysfs path of a character device","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","Content-Type":"text/plain; charset=\"utf-8\"","Content-Transfer-Encoding":"base64","Errors-To":"libcamera-devel-bounces@lists.libcamera.org","Sender":"\"libcamera-devel\" "},"content":"Add a helper function to lookup the sysfs path of a character device.\nStore the function in a new libcamera::sysfs namespace as there is not\nclass to host it.\n\nSuggested-by: Laurent Pinchart \nSigned-off-by: Niklas Söderlund \nReviewed-by: Laurent Pinchart \nReviewed-by: Jacopo Mondi \n---\n* Changes since v7\n- Rename parameter to deviceNode\n- Include sstream\n- Rename LOG category to SysFs\n- Update documentation\n- Print errno on failure\n`\n---\n include/libcamera/internal/meson.build | 1 +\n include/libcamera/internal/sysfs.h | 22 +++++++++++\n src/libcamera/meson.build | 1 +\n src/libcamera/sysfs.cpp | 52 ++++++++++++++++++++++++++\n 4 files changed, 76 insertions(+)\n create mode 100644 include/libcamera/internal/sysfs.h\n create mode 100644 src/libcamera/sysfs.cpp","diff":"diff --git a/include/libcamera/internal/meson.build b/include/libcamera/internal/meson.build\nindex d868eff47f920da0..150103388fdb219d 100644\n--- a/include/libcamera/internal/meson.build\n+++ b/include/libcamera/internal/meson.build\n@@ -25,6 +25,7 @@ libcamera_internal_headers = files([\n 'process.h',\n 'pub_key.h',\n 'semaphore.h',\n+ 'sysfs.h',\n 'thread.h',\n 'utils.h',\n 'v4l2_controls.h',\ndiff --git a/include/libcamera/internal/sysfs.h b/include/libcamera/internal/sysfs.h\nnew file mode 100644\nindex 0000000000000000..247a376ab7e0e8ee\n--- /dev/null\n+++ b/include/libcamera/internal/sysfs.h\n@@ -0,0 +1,22 @@\n+/* SPDX-License-Identifier: LGPL-2.1-or-later */\n+/*\n+ * Copyright (C) 2020, Google Inc.\n+ *\n+ * sysfs.h - Miscellaneous utility functions to access sysfs\n+ */\n+#ifndef __LIBCAMERA_INTERNAL_SYSFS_H__\n+#define __LIBCAMERA_INTERNAL_SYSFS_H__\n+\n+#include \n+\n+namespace libcamera {\n+\n+namespace sysfs {\n+\n+std::string charDevPath(const std::string &deviceNode);\n+\n+} /* namespace sysfs */\n+\n+} /* namespace libcamera */\n+\n+#endif /* __LIBCAMERA_INTERNAL_SYSFS_H__ */\ndiff --git a/src/libcamera/meson.build b/src/libcamera/meson.build\nindex 3aad4386ffc296db..bada45bcb11e9e88 100644\n--- a/src/libcamera/meson.build\n+++ b/src/libcamera/meson.build\n@@ -41,6 +41,7 @@ libcamera_sources = files([\n 'semaphore.cpp',\n 'signal.cpp',\n 'stream.cpp',\n+ 'sysfs.cpp',\n 'thread.cpp',\n 'timer.cpp',\n 'utils.cpp',\ndiff --git a/src/libcamera/sysfs.cpp b/src/libcamera/sysfs.cpp\nnew file mode 100644\nindex 0000000000000000..398df2c2be114908\n--- /dev/null\n+++ b/src/libcamera/sysfs.cpp\n@@ -0,0 +1,52 @@\n+/* SPDX-License-Identifier: LGPL-2.1-or-later */\n+/*\n+ * Copyright (C) 2020, Google Inc.\n+ *\n+ * sysfs.cpp - Miscellaneous utility functions to access sysfs\n+ */\n+\n+#include \"libcamera/internal/sysfs.h\"\n+\n+#include \n+#include \n+#include \n+\n+#include \"libcamera/internal/log.h\"\n+\n+/**\n+ * \\file sysfs.h\n+ * \\brief Miscellaneous utility functions to access sysfs\n+ */\n+\n+namespace libcamera {\n+\n+LOG_DEFINE_CATEGORY(SysFs);\n+\n+namespace sysfs {\n+\n+/**\n+ * \\brief Retrieve the sysfs path for a character device\n+ * \\param[in] deviceNode Path to character device node\n+ * \\return The sysfs path on success or an empty string on failure\n+ */\n+std::string charDevPath(const std::string &deviceNode)\n+{\n+\tstruct stat st;\n+\tint ret = stat(deviceNode.c_str(), &st);\n+\tif (ret < 0) {\n+\t\tret = -errno;\n+\t\tLOG(SysFs, Error)\n+\t\t\t<< \"Unable to stat '\" << deviceNode << \"': \"\n+\t\t\t<< strerror(-ret);\n+\t\treturn {};\n+\t}\n+\n+\tstd::ostringstream dev(\"/sys/dev/char/\", std::ios_base::ate);\n+\tdev << major(st.st_rdev) << \":\" << minor(st.st_rdev);\n+\n+\treturn dev.str();\n+}\n+\n+} /* namespace sysfs */\n+\n+} /* namespace libcamera */\n","prefixes":["libcamera-devel","v8","1/9"]}