[linux-2.6-block.git] / arch / um / kernel / exitcode.c

/*
 * Copyright (C) 2002 - 2007 Jeff Dike (jdike@{addtoit,linux.intel}.com)
 * Licensed under the GPL
 */

#include <linux/ctype.h>
#include <linux/init.h>
#include <linux/kernel.h>
#include <linux/proc_fs.h>
#include <linux/types.h>
#include <asm/uaccess.h>

/*
 * If read and write race, the read will still atomically read a valid
 * value.
 */
int uml_exitcode = 0;

static int read_proc_exitcode(char *page, char **start, off_t off,
			      int count, int *eof, void *data)
{
	int len, val;

	/*
	 * Save uml_exitcode in a local so that we don't need to guarantee
	 * that sprintf accesses it atomically.
	 */
	val = uml_exitcode;
	len = sprintf(page, "%d\n", val);
	len -= off;
	if (len <= off+count)
		*eof = 1;
	*start = page + off;
	if (len > count)
		len = count;
	if (len < 0)
		len = 0;
	return len;
}

static int write_proc_exitcode(struct file *file, const char __user *buffer,
			       unsigned long count, void *data)
{
	char *end, buf[sizeof("nnnnn\0")];
	int tmp;

	if (copy_from_user(buf, buffer, count))
		return -EFAULT;

	tmp = simple_strtol(buf, &end, 0);
	if ((*end != '\0') && !isspace(*end))
		return -EINVAL;

	uml_exitcode = tmp;
	return count;
}

static int make_proc_exitcode(void)
{
	struct proc_dir_entry *ent;

	ent = create_proc_entry("exitcode", 0600, NULL);
	if (ent == NULL) {
		printk(KERN_WARNING "make_proc_exitcode : Failed to register "
		       "/proc/exitcode\n");
		return 0;
	}

	ent->read_proc = read_proc_exitcode;
	ent->write_proc = write_proc_exitcode;

	return 0;
}

__initcall(make_proc_exitcode);
Commit	Line	Data
	1	/*
	2	* Copyright (C) 2002 - 2007 Jeff Dike (jdike@{addtoit,linux.intel}.com)
	3	* Licensed under the GPL
	4	*/
	5
	6	#include <linux/ctype.h>
	7	#include <linux/init.h>
	8	#include <linux/kernel.h>
	9	#include <linux/proc_fs.h>
	10	#include <linux/types.h>
	11	#include <asm/uaccess.h>
	12
	13	/*
	14	* If read and write race, the read will still atomically read a valid
	15	* value.
	16	*/
	17	int uml_exitcode = 0;
	18
	19	static int read_proc_exitcode(char page, char *start, off_t off,
	20	int count, int eof, void data)
	21	{
	22	int len, val;
	23
	24	/*
	25	* Save uml_exitcode in a local so that we don't need to guarantee
	26	* that sprintf accesses it atomically.
	27	*/
	28	val = uml_exitcode;
	29	len = sprintf(page, "%d\n", val);
	30	len -= off;
	31	if (len <= off+count)
	32	*eof = 1;
	33	*start = page + off;
	34	if (len > count)
	35	len = count;
	36	if (len < 0)
	37	len = 0;
	38	return len;
	39	}
	40
	41	static int write_proc_exitcode(struct file file, const char __user buffer,
	42	unsigned long count, void *data)
	43	{
	44	char *end, buf[sizeof("nnnnn\0")];
	45	int tmp;
	46
	47	if (copy_from_user(buf, buffer, count))
	48	return -EFAULT;
	49
	50	tmp = simple_strtol(buf, &end, 0);
	51	if ((end != '\0') && !isspace(end))
	52	return -EINVAL;
	53
	54	uml_exitcode = tmp;
	55	return count;
	56	}
	57
	58	static int make_proc_exitcode(void)
	59	{
	60	struct proc_dir_entry *ent;
	61
	62	ent = create_proc_entry("exitcode", 0600, NULL);
	63	if (ent == NULL) {
	64	printk(KERN_WARNING "make_proc_exitcode : Failed to register "
	65	"/proc/exitcode\n");
	66	return 0;
	67	}
	68
	69	ent->read_proc = read_proc_exitcode;
	70	ent->write_proc = write_proc_exitcode;
	71
	72	return 0;
	73	}
	74
	75	__initcall(make_proc_exitcode);