1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
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
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
|
/* example_module.c -- example module for vlock,
* the VT locking program for linux
*
* This program is copyright (C) 2007 Frank Benkstein, and is free
* software. It comes without any warranty, to the extent permitted by
* applicable law. You can redistribute it and/or modify it under the
* terms of the Do What The Fuck You Want To Public License, Version 2,
* as published by Sam Hocevar. See http://sam.zoy.org/wtfpl/COPYING
* for more details.
*/
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#include <errno.h>
/* Do not use any vlock specific headers here unless you intend to
* submit your module for inclusion. */
/* Include this header file to make sure the types of the dependencies
* and hooks are correct. */
#include "vlock_plugin.h"
/* Declare dependencies. Please see PLUGINS for their meaning. Empty
* dependencies can be left out. */
const char *preceeds[] = { "new", "all", NULL };
/* const char *succeeds[]; */
/* const char *requires[]; */
/* const char *needs[]; */
const char *depends[] = { "all", NULL };
/* const char *conflicts[]; */
/* Every hook has a void** argument ctx_ptr. When they are called
* ctx_ptr points to the same location and *ctx_ptr is initially set to
* NULL. Hook functions should pass state by defining a context struct
* and saving the pointer to it in *ctx_ptr instead of using global
* variables.
*/
struct example_context {
int a;
int b;
};
/* Do something that should happen at vlock's start here. An error in
* this hook aborts vlock. */
bool vlock_start(void **ctx_ptr)
{
struct example_context *ctx = malloc(sizeof *ctx);
if (ctx == NULL)
return false;
ctx->a = 23;
ctx->b = 42;
/* Save the context for use by the other hooks. */
*ctx_ptr = ctx;
return true;
}
/* Hooks that are not implemented should not be defined. */
/* Start a screensaver type action before the password prompt after a
* timeout. This hook must not block! */
/* bool vlock_save(void **); */
/* Abort a screensaver type action before the password prompt after a
* timeout. This hook must not block! */
/* bool vlock_save_abort(void **); */
/* Do something at the end of vlock. Error returns are ignored here. */
bool vlock_end(void **ctx_ptr)
{
struct example_context *ctx = *ctx_ptr;
bool result = true;
if (ctx != NULL) {
result = (ctx->a == 23 && ctx->b == 42);
free(ctx);
if (!result)
fprintf(stderr, "vlock-example_module: Whoops!\n");
}
return result;
}
|
