configs.c 2.79 KB
Newer Older
Linus Torvalds's avatar
Linus Torvalds committed
1 2 3 4 5
/*
 * kernel/configs.c
 * Echo the kernel .config file used to build the kernel
 *
 * Copyright (C) 2002 Khalid Aziz <khalid_aziz@hp.com>
6
 * Copyright (C) 2002 Randy Dunlap <rdunlap@xenotime.net>
Linus Torvalds's avatar
Linus Torvalds committed
7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30
 * 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>
31
#include <linux/uaccess.h>
Linus Torvalds's avatar
Linus Torvalds committed
32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60

/**************************************************/
/* 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

static ssize_t
ikconfig_read_current(struct file *file, char __user *buf,
		      size_t len, loff_t * offset)
{
61 62 63
	return simple_read_from_buffer(buf, len, offset,
				       kernel_config_data + MAGIC_SIZE,
				       kernel_config_data_size);
Linus Torvalds's avatar
Linus Torvalds committed
64 65
}

66
static const struct file_operations ikconfig_file_ops = {
Linus Torvalds's avatar
Linus Torvalds committed
67 68
	.owner = THIS_MODULE,
	.read = ikconfig_read_current,
69
	.llseek = default_llseek,
Linus Torvalds's avatar
Linus Torvalds committed
70 71 72 73 74 75 76
};

static int __init ikconfig_init(void)
{
	struct proc_dir_entry *entry;

	/* create the current config file */
77 78
	entry = proc_create("config.gz", S_IFREG | S_IRUGO, NULL,
			    &ikconfig_file_ops);
Linus Torvalds's avatar
Linus Torvalds committed
79 80 81
	if (!entry)
		return -ENOMEM;

82
	proc_set_size(entry, kernel_config_data_size);
Linus Torvalds's avatar
Linus Torvalds committed
83 84 85 86 87 88

	return 0;
}

static void __exit ikconfig_cleanup(void)
{
89
	remove_proc_entry("config.gz", NULL);
Linus Torvalds's avatar
Linus Torvalds committed
90 91 92 93 94
}

module_init(ikconfig_init);
module_exit(ikconfig_cleanup);

95 96
#endif /* CONFIG_IKCONFIG_PROC */

Linus Torvalds's avatar
Linus Torvalds committed
97 98 99
MODULE_LICENSE("GPL");
MODULE_AUTHOR("Randy Dunlap");
MODULE_DESCRIPTION("Echo the kernel .config file used to build the kernel");