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
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
|
/* GNU's read utmp module.
Copyright (C) 92, 93, 94, 95, 96, 1997, 1998 Free Software Foundation, Inc.
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, 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. */
/* Written by jla; revised by djm */
#include <config.h>
#include <sys/stat.h>
#if defined(STDC_HEADERS) || defined(HAVE_STRING_H)
# include <string.h>
#else
# include <strings.h>
#endif /* STDC_HEADERS || HAVE_STRING_H */
#include "readutmp.h"
char *xmalloc ();
/* Copy UT->ut_name into storage obtained from malloc. Then remove any
trailing spaces from the copy, NUL terminate it, and return the copy. */
char *
extract_trimmed_name (const STRUCT_UTMP *ut)
{
char *p, *trimmed_name;
trimmed_name = xmalloc (sizeof (ut->ut_name) + 1);
strncpy (trimmed_name, ut->ut_name, sizeof (ut->ut_name));
/* Append a trailing space character. Some systems pad names shorter than
the maximum with spaces, others pad with NULs. Remove any spaces. */
trimmed_name[sizeof (ut->ut_name)] = ' ';
p = strchr (trimmed_name, ' ');
if (p != NULL)
*p = '\0';
return trimmed_name;
}
/* Read the utmp file FILENAME into *UTMP_BUF, set *N_ENTRIES to the
number of entries read, and return zero. If there is any error,
return non-zero and don't modify the parameters. */
#ifdef HAVE_UTMPNAME
int
read_utmp (const char *filename, int *n_entries, STRUCT_UTMP **utmp_buf)
{
int count_utmp = 0;
int n_read;
STRUCT_UTMP *u;
STRUCT_UTMP *uptr;
STRUCT_UTMP *utmp_contents;
if (utmpname (filename))
{
return 1;
}
/* FIXME: going through the list twice is wasteful. */
/* count the entries in utmp */
setutent ();
while ((u = getutent ()) != NULL)
++count_utmp;
if (count_utmp == 0)
return 0;
utmp_contents = (STRUCT_UTMP *) xmalloc (count_utmp * sizeof (STRUCT_UTMP));
/* read the entries in utmp */
/* FIXME: can this fail? */
setutent ();
n_read = 0;
uptr = utmp_contents;
while ((u = getutent ()) != NULL)
{
++n_read;
if (n_read > count_utmp)
{
STRUCT_UTMP *old_utmp_contents = utmp_contents;
++count_utmp;
utmp_contents = (STRUCT_UTMP *) xrealloc (utmp_contents,
(count_utmp
* sizeof (STRUCT_UTMP)));
uptr = utmp_contents + (uptr - old_utmp_contents);
}
*uptr = *u;
++uptr;
}
if (n_read != count_utmp)
utmp_contents = (STRUCT_UTMP *) xrealloc (utmp_contents,
n_read * sizeof (STRUCT_UTMP));
/* FIXME: can this fail? */
endutent ();
*n_entries = n_read;
*utmp_buf = utmp_contents;
return 0;
}
#else
int
read_utmp (const char *filename, int *n_entries, STRUCT_UTMP **utmp_buf)
{
FILE *utmp;
struct stat file_stats;
size_t n_read;
size_t size;
STRUCT_UTMP *buf;
utmp = fopen (filename, "r");
if (utmp == NULL)
return 1;
fstat (fileno (utmp), &file_stats);
size = file_stats.st_size;
if (size > 0)
buf = (STRUCT_UTMP *) xmalloc (size);
else
{
fclose (utmp);
return 1;
}
/* Use < instead of != in case the utmp just grew. */
n_read = fread (buf, 1, size, utmp);
if (ferror (utmp) || fclose (utmp) == EOF
|| n_read < size)
return 1;
*n_entries = size / sizeof (STRUCT_UTMP);
*utmp_buf = buf;
return 0;
}
#endif /* HAVE_UTMPNAME */
|
