Commit | Line | Data |
---|---|---|
1da177e4 LT |
1 | /* |
2 | * Copyright (C) 2002 Jeff Dike (jdike@karaya.com) | |
3 | * Licensed under the GPL | |
4 | */ | |
5 | ||
6 | #include "linux/init.h" | |
7 | #include "linux/ctype.h" | |
8 | #include "linux/proc_fs.h" | |
9 | #include "asm/uaccess.h" | |
10 | ||
11 | /* If read and write race, the read will still atomically read a valid | |
12 | * value. | |
13 | */ | |
14 | int uml_exitcode = 0; | |
15 | ||
16 | static int read_proc_exitcode(char *page, char **start, off_t off, | |
17 | int count, int *eof, void *data) | |
18 | { | |
730760e9 | 19 | int len, val; |
1da177e4 | 20 | |
730760e9 JD |
21 | /* Save uml_exitcode in a local so that we don't need to guarantee |
22 | * that sprintf accesses it atomically. | |
23 | */ | |
24 | val = uml_exitcode; | |
25 | len = sprintf(page, "%d\n", val); | |
1da177e4 LT |
26 | len -= off; |
27 | if(len <= off+count) *eof = 1; | |
28 | *start = page + off; | |
29 | if(len > count) len = count; | |
30 | if(len < 0) len = 0; | |
31 | return(len); | |
32 | } | |
33 | ||
34 | static int write_proc_exitcode(struct file *file, const char __user *buffer, | |
35 | unsigned long count, void *data) | |
36 | { | |
37 | char *end, buf[sizeof("nnnnn\0")]; | |
38 | int tmp; | |
39 | ||
40 | if(copy_from_user(buf, buffer, count)) | |
41 | return(-EFAULT); | |
42 | tmp = simple_strtol(buf, &end, 0); | |
43 | if((*end != '\0') && !isspace(*end)) | |
44 | return(-EINVAL); | |
45 | uml_exitcode = tmp; | |
46 | return(count); | |
47 | } | |
48 | ||
49 | static int make_proc_exitcode(void) | |
50 | { | |
51 | struct proc_dir_entry *ent; | |
52 | ||
53 | ent = create_proc_entry("exitcode", 0600, &proc_root); | |
54 | if(ent == NULL){ | |
30f417c6 | 55 | printk(KERN_WARNING "make_proc_exitcode : Failed to register " |
1da177e4 LT |
56 | "/proc/exitcode\n"); |
57 | return(0); | |
58 | } | |
59 | ||
60 | ent->read_proc = read_proc_exitcode; | |
61 | ent->write_proc = write_proc_exitcode; | |
62 | ||
63 | return(0); | |
64 | } | |
65 | ||
66 | __initcall(make_proc_exitcode); | |
67 | ||
68 | /* | |
69 | * Overrides for Emacs so that we follow Linus's tabbing style. | |
70 | * Emacs will notice this stuff at the end of the file and automatically | |
71 | * adjust the settings for this buffer only. This must remain at the end | |
72 | * of the file. | |
73 | * --------------------------------------------------------------------------- | |
74 | * Local variables: | |
75 | * c-file-style: "linux" | |
76 | * End: | |
77 | */ |