aboutsummaryrefslogtreecommitdiffstats
path: root/src/log.c
blob: 140b50a2efe43fa72722637fbdaaaa3d1e8e798f (plain) (blame)
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
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
/*
 * Copyright (C) 2003-2011 The Music Player Daemon Project
 * http://www.musicpd.org
 *
 * 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 of the License, 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.,
 * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
 */

#include "config.h"
#include "log.h"
#include "conf.h"
#include "utils.h"
#include "fd_util.h"
#include "mpd_error.h"

#include <assert.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <string.h>
#include <stdarg.h>
#include <fcntl.h>
#include <stdio.h>
#include <stdlib.h>
#include <time.h>
#include <unistd.h>
#include <errno.h>
#include <glib.h>

#ifdef HAVE_SYSLOG
#include <syslog.h>
#endif

#undef G_LOG_DOMAIN
#define G_LOG_DOMAIN "log"

#define LOG_LEVEL_SECURE G_LOG_LEVEL_INFO

#define LOG_DATE_BUF_SIZE 16
#define LOG_DATE_LEN (LOG_DATE_BUF_SIZE - 1)

static GLogLevelFlags log_threshold = G_LOG_LEVEL_MESSAGE;

static const char *log_charset;

static bool stdout_mode = true;
static int out_fd;
static const char *out_filename;

static void redirect_logs(int fd)
{
	assert(fd >= 0);
	if (dup2(fd, STDOUT_FILENO) < 0)
		MPD_ERROR("problems dup2 stdout : %s\n", strerror(errno));
	if (dup2(fd, STDERR_FILENO) < 0)
		MPD_ERROR("problems dup2 stderr : %s\n", strerror(errno));
}

static const char *log_date(void)
{
	static char buf[LOG_DATE_BUF_SIZE];
	time_t t = time(NULL);
	strftime(buf, LOG_DATE_BUF_SIZE, "%b %d %H:%M : ", localtime(&t));
	return buf;
}

/**
 * Determines the length of the string excluding trailing whitespace
 * characters.
 */
static int
chomp_length(const char *p)
{
	size_t length = strlen(p);

	while (length > 0 && g_ascii_isspace(p[length - 1]))
		--length;

	return (int)length;
}

static void
file_log_func(const gchar *log_domain,
	      GLogLevelFlags log_level,
	      const gchar *message, G_GNUC_UNUSED gpointer user_data)
{
	char *converted;

	if (log_level > log_threshold)
		return;

	if (log_charset != NULL) {
		converted = g_convert_with_fallback(message, -1,
						    log_charset, "utf-8",
						    NULL, NULL, NULL, NULL);
		if (converted != NULL)
			message = converted;
	} else
		converted = NULL;

	if (log_domain == NULL)
		log_domain = "";

	fprintf(stderr, "%s%s%s%.*s\n",
		stdout_mode ? "" : log_date(),
		log_domain, *log_domain == 0 ? "" : ": ",
		chomp_length(message), message);

	g_free(converted);
}

static void
log_init_stdout(void)
{
	g_log_set_default_handler(file_log_func, NULL);
}

static int
open_log_file(void)
{
	assert(out_filename != NULL);

	return open_cloexec(out_filename, O_CREAT | O_WRONLY | O_APPEND, 0666);
}

static bool
log_init_file(const char *path, unsigned line, GError **error_r)
{
	out_filename = path;
	out_fd = open_log_file();
	if (out_fd < 0) {
		g_set_error(error_r, log_quark(), errno,
			    "failed to open log file \"%s\" (config line %u): %s",
			    path, line, g_strerror(errno));
		return false;
	}

	g_log_set_default_handler(file_log_func, NULL);
	return true;
}

#ifdef HAVE_SYSLOG

static int
glib_to_syslog_level(GLogLevelFlags log_level)
{
	switch (log_level & G_LOG_LEVEL_MASK) {
	case G_LOG_LEVEL_ERROR:
	case G_LOG_LEVEL_CRITICAL:
		return LOG_ERR;

	case G_LOG_LEVEL_WARNING:
		return LOG_WARNING;

	case G_LOG_LEVEL_MESSAGE:
		return LOG_NOTICE;

	case G_LOG_LEVEL_INFO:
		return LOG_INFO;

	case G_LOG_LEVEL_DEBUG:
		return LOG_DEBUG;

	default:
		return LOG_NOTICE;
	}
}

static void
syslog_log_func(const gchar *log_domain,
		GLogLevelFlags log_level, const gchar *message,
		G_GNUC_UNUSED gpointer user_data)
{
	if (stdout_mode) {
		/* fall back to the file log function during
		   startup */
		file_log_func(log_domain, log_level,
			      message, user_data);
		return;
	}

	if (log_level > log_threshold)
		return;

	if (log_domain == NULL)
		log_domain = "";

	syslog(glib_to_syslog_level(log_level), "%s%s%.*s",
	       log_domain, *log_domain == 0 ? "" : ": ",
	       chomp_length(message), message);
}

static void
log_init_syslog(void)
{
	assert(out_filename == NULL);

	openlog(PACKAGE, 0, LOG_DAEMON);
	g_log_set_default_handler(syslog_log_func, NULL);
}

#endif

static inline GLogLevelFlags
parse_log_level(const char *value, unsigned line)
{
	if (0 == strcmp(value, "default"))
		return G_LOG_LEVEL_MESSAGE;
	if (0 == strcmp(value, "secure"))
		return LOG_LEVEL_SECURE;
	else if (0 == strcmp(value, "verbose"))
		return G_LOG_LEVEL_DEBUG;
	else {
		MPD_ERROR("unknown log level \"%s\" at line %u\n",
			  value, line);
		return G_LOG_LEVEL_MESSAGE;
	}
}

void
log_early_init(bool verbose)
{
	if (verbose)
		log_threshold = G_LOG_LEVEL_DEBUG;

	log_init_stdout();
}

bool
log_init(bool verbose, bool use_stdout, GError **error_r)
{
	const struct config_param *param;

	g_get_charset(&log_charset);

	if (verbose)
		log_threshold = G_LOG_LEVEL_DEBUG;
	else if ((param = config_get_param(CONF_LOG_LEVEL)) != NULL)
		log_threshold = parse_log_level(param->value, param->line);

	if (use_stdout) {
		log_init_stdout();
		return true;
	} else {
		param = config_get_param(CONF_LOG_FILE);
		if (param == NULL) {
#ifdef HAVE_SYSLOG
			/* no configuration: default to syslog (if
			   available) */
			log_init_syslog();
			return true;
#else
			g_set_error(error_r, log_quark(), 0,
				    "config parameter \"%s\" not found",
				    CONF_LOG_FILE);
			return false;
#endif
#ifdef HAVE_SYSLOG
		} else if (strcmp(param->value, "syslog") == 0) {
			log_init_syslog();
			return true;
#endif
		} else {
			const char *path = config_get_path(CONF_LOG_FILE);
			assert(path != NULL);

			return log_init_file(path, param->line, error_r);
		}
	}
}

void setup_log_output(bool use_stdout)
{
	fflush(NULL);
	if (!use_stdout) {
#ifndef WIN32
		if (out_filename == NULL)
			out_fd = open("/dev/null", O_WRONLY);
#endif

		if (out_fd >= 0) {
			redirect_logs(out_fd);
			close(out_fd);
		}

		stdout_mode = false;
		log_charset = NULL;
	}
}

int cycle_log_files(void)
{
	int fd;

	if (stdout_mode || out_filename == NULL)
		return 0;
	assert(out_filename);

	g_debug("Cycling log files...\n");
	close_log_files();

	fd = open_log_file();
	if (fd < 0) {
		g_warning("error re-opening log file: %s\n", out_filename);
		return -1;
	}

	redirect_logs(fd);
	g_debug("Done cycling log files\n");
	return 0;
}

void close_log_files(void)
{
	if (stdout_mode)
		return;

#ifdef HAVE_SYSLOG
	if (out_filename == NULL)
		closelog();
#endif
}