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
|
/* $Id$
**
** File handling for the wallet client.
**
** Written by Russ Allbery <rra@stanford.edu>
** Copyright 2007, 2008 Board of Trustees, Leland Stanford Jr. University
**
** See LICENSE for licensing terms.
*/
#include <config.h>
#include <system.h>
#include <fcntl.h>
#include <client/internal.h>
#include <util/util.h>
/*
** Given a filename, some data, and a length, write that data to the given
** file safely, but overwrite any existing file by that name.
*/
void
overwrite_file(const char *name, const void *data, size_t length)
{
int fd;
ssize_t status;
if (access(name, F_OK) == 0)
if (unlink(name) < 0)
sysdie("unable to delete existing file %s", name);
fd = open(name, O_WRONLY | O_CREAT | O_EXCL, 0600);
if (fd < 0)
sysdie("open of %s failed", name);
if (length > 0) {
status = write(fd, data, length);
if (status < 0)
sysdie("write to %s failed", name);
else if (status != (ssize_t) length)
die("write to %s truncated", name);
}
if (close(fd) < 0)
sysdie("close of %s failed (file probably truncated)", name);
}
/*
** Given a filename, some data, and a length, write that data to the given
** file safely and atomically by creating file.new, writing the data, linking
** file to file.bak, and then renaming file.new to file.
*/
void
write_file(const char *name, const void *data, size_t length)
{
char *temp, *backup;
temp = concat(name, ".new", (char *) 0);
backup = concat(name, ".bak", (char *) 0);
overwrite_file(temp, data, length);
if (access(name, F_OK) == 0) {
if (access(backup, F_OK) == 0)
if (unlink(backup) < 0)
sysdie("unlink of old backup %s failed", backup);
if (link(name, backup) < 0)
sysdie("link of %s to %s failed", name, backup);
}
if (rename(temp, name) < 0)
sysdie("rename of %s to %s failed", temp, name);
free(temp);
free(backup);
}
/*
** Given a remctl object, the command prefix, object type, and object name,
** and a file (which may be NULL), send a wallet get command and write the
** results to the provided file. If the file is NULL, write the results to
** standard output instead. Returns 0 on success and an exit status on
** failure.
*/
int
get_file(struct remctl *r, const char *prefix, const char *type,
const char *name, const char *file)
{
const char *command[5];
char *data = NULL;
size_t length = 0;
int status;
command[0] = prefix;
command[1] = "get";
command[2] = type;
command[3] = name;
command[4] = NULL;
status = run_command(r, command, &data, &length);
if (status != 0)
return status;
/* The empty string is valid data. */
if (data == NULL)
length = 0;
if (file != NULL)
write_file(file, data, length);
else if (length > 0) {
if (fwrite(data, length, 1, stdout) != 1)
sysdie("cannot write to standard output");
}
if (data != NULL)
free(data);
return 0;
}
|
