server/common/logger.C

/*
 * This file is part of Deliantra, the Roguelike Realtime MMORPG.
 * 
 * Copyright (©) 2005,2006,2007,2008,2009,2010 Marc Alexander Lehmann / Robin Redeker / the Deliantra team
 * 
 * Deliantra is free software: you can redistribute it and/or modify it under
 * the terms of the Affero GNU General Public License as published by the
 * Free Software Foundation, either version 3 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 Affero GNU General Public License
 * and the GNU General Public License along with this program. If not, see
 * <http://www.gnu.org/licenses/>.
 * 
 * The authors can be reached via e-mail to <support@deliantra.net>
 */

#include <cstdarg>
#include <cstring>

#include <vector>

#include <sys/uio.h>
#include <pthread.h>

#include "global.h"
#include "dynbuf.h"
#include "util.h"

struct logline
{
  struct timeval tv;
  char *buf; // includes PREFIX_LEN garbage bytes
  int len;
  int flags;
};

static SMUTEX(mutex);
static SMUTEX(fdlock);
static SCOND(cond);
static int logfd = STDERR_FILENO;
static int logsync = 1;
static std::vector<logline, slice_allocator<logline> > queue;

int log_setfd (int fd)
{
  SMUTEX_LOCK (fdlock);
  int old = logfd;
  logfd = fd < 0 ? STDERR_FILENO : fd;
  SMUTEX_UNLOCK (fdlock);

  return old;
}

#define PREFIX_LEN sizeof ("0000-00-00 00:00:00.0000+") - 1

static void
log_sync (logline &line)
{
  struct tm lt;
  char pfx [PREFIX_LEN];

  localtime_r (&line.tv.tv_sec, &lt);

  sprintf (pfx, "%04d-%02d-%02d %02d:%02d:%02d.%04d",
    lt.tm_year + 1900,
    lt.tm_mon + 1,
    lt.tm_mday,
    lt.tm_hour,
    lt.tm_min,
    lt.tm_sec,
    (int)(line.tv.tv_usec / 100)
  );

  pfx [PREFIX_LEN - 1] = line.flags & logSync ? '=' : ' ';

  struct iovec iov [2];

  iov [0].iov_base = pfx;
  iov [0].iov_len = PREFIX_LEN;

  char *buf = line.buf;

  if (logsync != 2)
    SMUTEX_LOCK (fdlock);

  while (char *end = strchr (buf, '\n'))
    {
      iov [1].iov_base = buf;
      iov [1].iov_len = end - buf + 1;

      writev (STDERR_FILENO, iov, 2);
      if (logfd != STDERR_FILENO)
        writev (logfd, iov, 2);

      buf = end + 1;

      if (buf == line.buf + line.len)
        break;

      pfx [PREFIX_LEN - 1] = '+';
    }

  if (logsync != 2)
    SMUTEX_UNLOCK (fdlock);

  sfree (line.buf, line.len);
}

static void *
logthread_proc (void *arg)
{
  int idx = 0;

  for (;;)
    {
      logline line;

      SMUTEX_LOCK (mutex);

      while (queue.empty ())
        SCOND_WAIT (cond, mutex);

      line = queue [idx++];

      // this algorithm could result in an ever-increasing vector
      // size if we log faster than we can write, but if that happens
      // we have bigger problems.
      if (idx == queue.size ())
        {
          queue.clear ();
          idx = 0;
        }

      SMUTEX_UNLOCK (mutex);

      log_sync (line);
    }
}

void
log_cleanup ()
{
  logsync = 1;

  for (;;)
    {
      int done;

      SMUTEX_LOCK (mutex);
      done = queue.empty ();
      SMUTEX_UNLOCK (mutex);

      if (done)
        break;

      usleep (10000);
      SMUTEX_LOCK (fdlock);
      SMUTEX_UNLOCK (fdlock);
    }
}

static void
af_child ()
{
  logsync = 2;
}

static struct logthread : thread
{
  logthread ()
  {
    pthread_atfork (0, 0, af_child);
    start (logthread_proc);
    logsync = 0;
  }
} logthread;

void
LOG (int flags, const_utf8_string format, ...)
{
  int level = flags & 15;

  if (level > settings.debug)
    return;

  logline line;
  gettimeofday (&line.tv, 0);

  static dynbuf_text buf;

  va_list ap;
  va_start (ap, format);
  buf.vprintf (format, ap);
  va_end (ap);

  buf << '\n';

  line.buf = buf.linearise ();
  line.len = buf.size ();

  if (line.buf [line.len - 2] == '\n')
    --line.len;

  line.buf = salloc<char> (line.len, line.buf);

  buf.clear ();

  if (logsync)
    flags |= logSync;

  if (flags & logBacktrace)
    {
      line.buf [line.len - 1] = 0;
      log_backtrace (line.buf);
      line.buf [line.len - 1] = '\n';
    }

  line.flags = flags;

  if (line.flags & logSync)
    log_sync (line);
  else
    {
      SMUTEX_LOCK (mutex);
      queue.push_back (line);
      SMUTEX_UNLOCK (mutex);
      SCOND_SIGNAL (cond);
    }
}

static int suspended;

void
log_suspend ()
{
  if (!suspended++)
    {
      LOG (llevDebug, "logging suspended.");
      SMUTEX_LOCK (fdlock);
    }
}

void
log_resume ()
{
  if (!--suspended)
    {
      SMUTEX_UNLOCK (fdlock);
      LOG (llevDebug, "logging resumed.");
    }
}

Revision:	1.24
Committed:	Sun Apr 11 17:27:51 2010 UTC (14 years, 2 months ago) by root
Content type:	text/plain
Branch:	MAIN
Changes since 1.23:	+38 -4 lines
Log Message:	logfile suspend/resume
#	Content
1	/*
2	* This file is part of Deliantra, the Roguelike Realtime MMORPG.
3	*
4	* Copyright (©) 2005,2006,2007,2008,2009,2010 Marc Alexander Lehmann / Robin Redeker / the Deliantra team
5	*
6	* Deliantra is free software: you can redistribute it and/or modify it under
7	* the terms of the Affero GNU General Public License as published by the
8	* Free Software Foundation, either version 3 of the License, or (at your
9	* option) any later version.
10	*
11	* This program is distributed in the hope that it will be useful,
12	* but WITHOUT ANY WARRANTY; without even the implied warranty of
13	* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14	* GNU General Public License for more details.
15	*
16	* You should have received a copy of the Affero GNU General Public License
17	* and the GNU General Public License along with this program. If not, see
18	* <http://www.gnu.org/licenses/>.
19	*
20	* The authors can be reached via e-mail to <support@deliantra.net>
21	*/
22
23	#include <cstdarg>
24	#include <cstring>
25
26	#include <vector>
27
28	#include <sys/uio.h>
29	#include <pthread.h>
30
31	#include "global.h"
32	#include "dynbuf.h"
33	#include "util.h"
34
35	struct logline
36	{
37	struct timeval tv;
38	char *buf; // includes PREFIX_LEN garbage bytes
39	int len;
40	int flags;
41	};
42
43	static SMUTEX(mutex);
44	static SMUTEX(fdlock);
45	static SCOND(cond);
46	static int logfd = STDERR_FILENO;
47	static int logsync = 1;
48	static std::vector<logline, slice_allocator<logline> > queue;
49
50	int log_setfd (int fd)
51	{
52	SMUTEX_LOCK (fdlock);
53	int old = logfd;
54	logfd = fd < 0 ? STDERR_FILENO : fd;
55	SMUTEX_UNLOCK (fdlock);
56
57	return old;
58	}
59
60	#define PREFIX_LEN sizeof ("0000-00-00 00:00:00.0000+") - 1
61
62	static void
63	log_sync (logline &line)
64	{
65	struct tm lt;
66	char pfx [PREFIX_LEN];
67
68	localtime_r (&line.tv.tv_sec, &lt);
69
70	sprintf (pfx, "%04d-%02d-%02d %02d:%02d:%02d.%04d",
71	lt.tm_year + 1900,
72	lt.tm_mon + 1,
73	lt.tm_mday,
74	lt.tm_hour,
75	lt.tm_min,
76	lt.tm_sec,
77	(int)(line.tv.tv_usec / 100)
78	);
79
80	pfx [PREFIX_LEN - 1] = line.flags & logSync ? '=' : ' ';
81
82	struct iovec iov [2];
83
84	iov [0].iov_base = pfx;
85	iov [0].iov_len = PREFIX_LEN;
86
87	char *buf = line.buf;
88
89	if (logsync != 2)
90	SMUTEX_LOCK (fdlock);
91
92	while (char *end = strchr (buf, '\n'))
93	{
94	iov [1].iov_base = buf;
95	iov [1].iov_len = end - buf + 1;
96
97	writev (STDERR_FILENO, iov, 2);
98	if (logfd != STDERR_FILENO)
99	writev (logfd, iov, 2);
100
101	buf = end + 1;
102
103	if (buf == line.buf + line.len)
104	break;
105
106	pfx [PREFIX_LEN - 1] = '+';
107	}
108
109	if (logsync != 2)
110	SMUTEX_UNLOCK (fdlock);
111
112	sfree (line.buf, line.len);
113	}
114
115	static void *
116	logthread_proc (void *arg)
117	{
118	int idx = 0;
119
120	for (;;)
121	{
122	logline line;
123
124	SMUTEX_LOCK (mutex);
125
126	while (queue.empty ())
127	SCOND_WAIT (cond, mutex);
128
129	line = queue [idx++];
130
131	// this algorithm could result in an ever-increasing vector
132	// size if we log faster than we can write, but if that happens
133	// we have bigger problems.
134	if (idx == queue.size ())
135	{
136	queue.clear ();
137	idx = 0;
138	}
139
140	SMUTEX_UNLOCK (mutex);
141
142	log_sync (line);
143	}
144	}
145
146	void
147	log_cleanup ()
148	{
149	logsync = 1;
150
151	for (;;)
152	{
153	int done;
154
155	SMUTEX_LOCK (mutex);
156	done = queue.empty ();
157	SMUTEX_UNLOCK (mutex);
158
159	if (done)
160	break;
161
162	usleep (10000);
163	SMUTEX_LOCK (fdlock);
164	SMUTEX_UNLOCK (fdlock);
165	}
166	}
167
168	static void
169	af_child ()
170	{
171	logsync = 2;
172	}
173
174	static struct logthread : thread
175	{
176	logthread ()
177	{
178	pthread_atfork (0, 0, af_child);
179	start (logthread_proc);
180	logsync = 0;
181	}
182	} logthread;
183
184	void
185	LOG (int flags, const_utf8_string format, ...)
186	{
187	int level = flags & 15;
188
189	if (level > settings.debug)
190	return;
191
192	logline line;
193	gettimeofday (&line.tv, 0);
194
195	static dynbuf_text buf;
196
197	va_list ap;
198	va_start (ap, format);
199	buf.vprintf (format, ap);
200	va_end (ap);
201
202	buf << '\n';
203
204	line.buf = buf.linearise ();
205	line.len = buf.size ();
206
207	if (line.buf [line.len - 2] == '\n')
208	--line.len;
209
210	line.buf = salloc<char> (line.len, line.buf);
211
212	buf.clear ();
213
214	if (logsync)
215	flags \|= logSync;
216
217	if (flags & logBacktrace)
218	{
219	line.buf [line.len - 1] = 0;
220	log_backtrace (line.buf);
221	line.buf [line.len - 1] = '\n';
222	}
223
224	line.flags = flags;
225
226	if (line.flags & logSync)
227	log_sync (line);
228	else
229	{
230	SMUTEX_LOCK (mutex);
231	queue.push_back (line);
232	SMUTEX_UNLOCK (mutex);
233	SCOND_SIGNAL (cond);
234	}
235	}
236
237	static int suspended;
238
239	void
240	log_suspend ()
241	{
242	if (!suspended++)
243	{
244	LOG (llevDebug, "logging suspended.");
245	SMUTEX_LOCK (fdlock);
246	}
247	}
248
249	void
250	log_resume ()
251	{
252	if (!--suspended)
253	{
254	SMUTEX_UNLOCK (fdlock);
255	LOG (llevDebug, "logging resumed.");
256	}
257	}
258