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
158
159
160
161
162
163
164
165
166
167
|
/* -*- mode: C; c-file-style: "gnu"; indent-tabs-mode: nil; -*-
*
* Copyright (C) 2012 William Jon McCann <mccann@redhat.com>
* Copyright (C) 2012 Colin Walters <walters@verbum.org>
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation; either
* version 2 of the License, or (at your option) any later version.
*
* This library 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
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with this library; if not, write to the
* Free Software Foundation, Inc., 59 Temple Place - Suite 330,
* Boston, MA 02111-1307, USA.
*/
#include "config.h"
#ifndef _GNU_SOURCE
#define _GNU_SOURCE
#endif
#ifdef ENABLE_SYSTEMD_JOURNAL
#define SD_JOURNAL_SUPPRESS_LOCATION
#include <systemd/sd-journal.h>
#endif
#include <glib-unix.h>
#define _GSYSTEM_NO_LOCAL_ALLOC
#include "libgsystem.h"
/**
* gs_log_structured:
* @message: Text message to send
* @keys: (allow-none) (array zero-terminated=1) (element-type utf8): Optional structured data
*
* Log structured data in an operating-system specific fashion. The
* parameter @opts should be an array of UTF-8 KEY=VALUE strings.
* This function does not support binary data. See
* http://www.freedesktop.org/software/systemd/man/systemd.journal-fields.html
* for more information about fields that can be used on a systemd
* system.
*/
void
gs_log_structured (const char *message,
const char *const *keys)
{
#ifdef ENABLE_SYSTEMD_JOURNAL
const char *const*iter;
char *msgkey;
guint i, n_opts;
struct iovec *iovs;
for (n_opts = 0, iter = keys; *iter; iter++, n_opts++)
;
n_opts++; /* Add one for MESSAGE= */
iovs = g_alloca (sizeof (struct iovec) * n_opts);
for (i = 0, iter = keys; *iter; iter++, i++) {
iovs[i].iov_base = (char*)keys[i];
iovs[i].iov_len = strlen (keys[i]);
}
g_assert(i == n_opts-1);
msgkey = g_strconcat ("MESSAGE=", message, NULL);
iovs[i].iov_base = msgkey;
iovs[i].iov_len = strlen (msgkey);
// The code location isn't useful since we're wrapping
sd_journal_sendv (iovs, n_opts);
g_free (msgkey);
#else
g_print ("%s\n", message);
#endif
}
/**
* gs_stdout_is_journal:
*
* Use this function when you want your code to behave differently
* depeneding on whether your program was started as a systemd unit,
* or e.g. interactively at a terminal.
*
* Returns: %TRUE if stdout is (probably) connnected to the systemd journal
*/
gboolean
gs_stdout_is_journal (void)
{
static gsize initialized;
static gboolean stdout_is_socket;
if (g_once_init_enter (&initialized))
{
guint64 pid = (guint64) getpid ();
char *fdpath = g_strdup_printf ("/proc/%" G_GUINT64_FORMAT "/fd/1", pid);
char buf[1024];
ssize_t bytes_read;
if ((bytes_read = readlink (fdpath, buf, sizeof(buf) - 1)) != -1)
{
buf[bytes_read] = '\0';
stdout_is_socket = g_str_has_prefix (buf, "socket:");
}
else
stdout_is_socket = FALSE;
g_free (fdpath);
g_once_init_leave (&initialized, TRUE);
}
return stdout_is_socket;
}
/**
* gs_log_structured_print:
* @message: A message to log
* @keys: (allow-none) (array zero-terminated=1) (element-type utf8): Optional structured data
*
* Like gs_log_structured(), but also print to standard output (if it
* is not already connected to the system log).
*/
void
gs_log_structured_print (const char *message,
const char *const *keys)
{
gs_log_structured (message, keys);
#ifdef ENABLE_SYSTEMD_JOURNAL
if (!gs_stdout_is_journal ())
g_print ("%s\n", message);
#endif
}
/**
* gs_log_structured_print_id_v:
* @message_id: A unique MESSAGE_ID
* @format: A format string
*
* The provided @message_id is a unique MESSAGE_ID (see <ulink url="http://www.freedesktop.org/software/systemd/man/systemd.journal-fields.html"> for more information).
*
* This function otherwise acts as gs_log_structured_print(), taking
* @format as a format string.
*/
void
gs_log_structured_print_id_v (const char *message_id,
const char *format,
...)
{
char *keys[] = { NULL, NULL };
char *msg;
va_list args;
va_start (args, format);
msg = g_strdup_vprintf (format, args);
va_end (args);
keys[0] = g_strconcat ("MESSAGE_ID=", message_id, NULL);
gs_log_structured_print (msg, (const char *const *)keys);
g_free (keys[0]);
g_free (msg);
}
|
