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Diffstat (limited to 'Documentation/DocBook/procfs_example.c')
| -rw-r--r-- | Documentation/DocBook/procfs_example.c | 201 |
1 files changed, 0 insertions, 201 deletions
diff --git a/Documentation/DocBook/procfs_example.c b/Documentation/DocBook/procfs_example.c deleted file mode 100644 index a5b11793b1e..00000000000 --- a/Documentation/DocBook/procfs_example.c +++ /dev/null @@ -1,201 +0,0 @@ -/* - * procfs_example.c: an example proc interface - * - * Copyright (C) 2001, Erik Mouw (mouw@nl.linux.org) - * - * This file accompanies the procfs-guide in the Linux kernel - * source. Its main use is to demonstrate the concepts and - * functions described in the guide. - * - * This software has been developed while working on the LART - * computing board (http://www.lartmaker.nl), which was sponsored - * by the Delt University of Technology projects Mobile Multi-media - * Communications and Ubiquitous Communications. - * - * 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. 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., 59 Temple Place, - * Suite 330, Boston, MA 02111-1307 USA - * - */ - -#include <linux/module.h> -#include <linux/kernel.h> -#include <linux/init.h> -#include <linux/proc_fs.h> -#include <linux/jiffies.h> -#include <asm/uaccess.h> - - -#define MODULE_VERS "1.0" -#define MODULE_NAME "procfs_example" - -#define FOOBAR_LEN 8 - -struct fb_data_t { - char name[FOOBAR_LEN + 1]; - char value[FOOBAR_LEN + 1]; -}; - - -static struct proc_dir_entry *example_dir, *foo_file, - *bar_file, *jiffies_file, *symlink; - - -struct fb_data_t foo_data, bar_data; - - -static int proc_read_jiffies(char *page, char **start, - off_t off, int count, - int *eof, void *data) -{ - int len; - - len = sprintf(page, "jiffies = %ld\n", - jiffies); - - return len; -} - - -static int proc_read_foobar(char *page, char **start, - off_t off, int count, - int *eof, void *data) -{ - int len; - struct fb_data_t *fb_data = (struct fb_data_t *)data; - - /* DON'T DO THAT - buffer overruns are bad */ - len = sprintf(page, "%s = '%s'\n", - fb_data->name, fb_data->value); - - return len; -} - - -static int proc_write_foobar(struct file *file, - const char *buffer, - unsigned long count, - void *data) -{ - int len; - struct fb_data_t *fb_data = (struct fb_data_t *)data; - - if(count > FOOBAR_LEN) - len = FOOBAR_LEN; - else - len = count; - - if(copy_from_user(fb_data->value, buffer, len)) - return -EFAULT; - - fb_data->value[len] = '\0'; - - return len; -} - - -static int __init init_procfs_example(void) -{ - int rv = 0; - - /* create directory */ - example_dir = proc_mkdir(MODULE_NAME, NULL); - if(example_dir == NULL) { - rv = -ENOMEM; - goto out; - } - /* create jiffies using convenience function */ - jiffies_file = create_proc_read_entry("jiffies", - 0444, example_dir, - proc_read_jiffies, - NULL); - if(jiffies_file == NULL) { - rv = -ENOMEM; - goto no_jiffies; - } - - /* create foo and bar files using same callback - * functions - */ - foo_file = create_proc_entry("foo", 0644, example_dir); - if(foo_file == NULL) { - rv = -ENOMEM; - goto no_foo; - } - - strcpy(foo_data.name, "foo"); - strcpy(foo_data.value, "foo"); - foo_file->data = &foo_data; - foo_file->read_proc = proc_read_foobar; - foo_file->write_proc = proc_write_foobar; - - bar_file = create_proc_entry("bar", 0644, example_dir); - if(bar_file == NULL) { - rv = -ENOMEM; - goto no_bar; - } - - strcpy(bar_data.name, "bar"); - strcpy(bar_data.value, "bar"); - bar_file->data = &bar_data; - bar_file->read_proc = proc_read_foobar; - bar_file->write_proc = proc_write_foobar; - - /* create symlink */ - symlink = proc_symlink("jiffies_too", example_dir, - "jiffies"); - if(symlink == NULL) { - rv = -ENOMEM; - goto no_symlink; - } - - /* everything OK */ - printk(KERN_INFO "%s %s initialised\n", - MODULE_NAME, MODULE_VERS); - return 0; - -no_symlink: - remove_proc_entry("bar", example_dir); -no_bar: - remove_proc_entry("foo", example_dir); -no_foo: - remove_proc_entry("jiffies", example_dir); -no_jiffies: - remove_proc_entry(MODULE_NAME, NULL); -out: - return rv; -} - - -static void __exit cleanup_procfs_example(void) -{ - remove_proc_entry("jiffies_too", example_dir); - remove_proc_entry("bar", example_dir); - remove_proc_entry("foo", example_dir); - remove_proc_entry("jiffies", example_dir); - remove_proc_entry(MODULE_NAME, NULL); - - printk(KERN_INFO "%s %s removed\n", - MODULE_NAME, MODULE_VERS); -} - - -module_init(init_procfs_example); -module_exit(cleanup_procfs_example); - -MODULE_AUTHOR("Erik Mouw"); -MODULE_DESCRIPTION("procfs examples"); -MODULE_LICENSE("GPL"); |