/* * kernel/configs.c * Echo the kernel .config file used to build the kernel * * Copyright (C) 2002 Khalid Aziz <khalid_aziz@hp.com> * Copyright (C) 2002 Randy Dunlap <rdunlap@xenotime.net> * Copyright (C) 2002 Al Stone <ahs3@fc.hp.com> * Copyright (C) 2002 Hewlett-Packard Company * * This program is free software; you can redistribute it and/or modify * it under the terms of the GNU General Public License as published by * the Free Software Foundation; either version 2 of the License, or (at * your option) any later version. * * This program is distributed in the hope that it will be useful, but * WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE, GOOD TITLE or * NON INFRINGEMENT. See the GNU General Public License for more * details. * * You should have received a copy of the GNU General Public License * along with this program; if not, write to the Free Software * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. */ #include <linux/kernel.h> #include <linux/module.h> #include <linux/proc_fs.h> #include <linux/seq_file.h> #include <linux/init.h> #include <asm/uaccess.h> /**************************************************/ /* the actual current config file */ /* * Define kernel_config_data and kernel_config_data_size, which contains the * wrapped and compressed configuration file. The file is first compressed * with gzip and then bounded by two eight byte magic numbers to allow * extraction from a binary kernel image: * * IKCFG_ST * <image> * IKCFG_ED */ #define MAGIC_START "IKCFG_ST" #define MAGIC_END "IKCFG_ED" #include "config_data.h" #define MAGIC_SIZE (sizeof(MAGIC_START) - 1) #define kernel_config_data_size \ (sizeof(kernel_config_data) - 1 - MAGIC_SIZE * 2) #ifdef CONFIG_IKCONFIG_PROC /**************************************************/ /* globals and useful constants */ static ssize_t ikconfig_read_current(struct file *file, char __user *buf, size_t len, loff_t * offset) { loff_t pos = *offset; ssize_t count; if (pos >= kernel_config_data_size) return 0; count = min(len, (size_t)(kernel_config_data_size - pos)); if (copy_to_user(buf, kernel_config_data + MAGIC_SIZE + pos, count)) return -EFAULT; *offset += count; return count; } static struct file_operations ikconfig_file_ops = { .owner = THIS_MODULE, .read = ikconfig_read_current, }; /***************************************************/ /* ikconfig_init: start up everything we need to */ static int __init ikconfig_init(void) { struct proc_dir_entry *entry; /* create the current config file */ entry = create_proc_entry("config.gz", S_IFREG | S_IRUGO, &proc_root); if (!entry) return -ENOMEM; entry->proc_fops = &ikconfig_file_ops; entry->size = kernel_config_data_size; return 0; } /***************************************************/ /* ikconfig_cleanup: clean up our mess */ static void __exit ikconfig_cleanup(void) { remove_proc_entry("config.gz", &proc_root); } module_init(ikconfig_init); module_exit(ikconfig_cleanup); MODULE_LICENSE("GPL"); MODULE_AUTHOR("Randy Dunlap"); MODULE_DESCRIPTION("Echo the kernel .config file used to build the kernel"); #endif /* CONFIG_IKCONFIG_PROC */