rework logging system

reimplement the old mu-log.[ch] into mu-logging.{cc,hh}

If available (and using an appropriately equipped glib), log to the
systemd journal

Only g_criticals have stderr output, all the other g_* go to the log
file / journal.

4 files changed, 2 insertions, 434 deletions

diff --git a/lib/utils/Makefile.am b/lib/utils/Makefile.am
index 551eb1d..9c5681d 100644
--- a/lib/utils/Makefile.am
+++ b/lib/utils/Makefile.am
@@ -49,8 +49,8 @@ libmu_utils_la_SOURCES=						\
 	mu-date.c						\
 	mu-date.h						\
 	mu-error.hh						\
-	mu-log.c						\
-	mu-log.h						\
+	mu-logger.cc						\
+	mu-logger.hh						\
 	mu-command-parser.cc					\
 	mu-command-parser.hh					\
 	mu-readline.cc						\
diff --git a/lib/utils/mu-log.c b/lib/utils/mu-log.c
deleted file mode 100644
index 92ea188..0000000
--- a/lib/utils/mu-log.c
+++ /dev/null
@@ -1,319 +0,0 @@
-/* -*-mode: c; tab-width: 8; indent-tabs-mode: t; c-basic-offset: 8 -*-*/
-
-/*
-** Copyright (C) 2008-2016 Dirk-Jan C. Binnema <djcb@djcbsoftware.nl>
-**
-** 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 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 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.
-**
-*/
-
-#if HAVE_CONFIG_H
-#include <config.h>
-#endif /*HAVE_CONFIG_H*/
-
-#include "mu-log.h"
-
-#include <stdio.h>
-#include <stdlib.h>
-#include <unistd.h>
-#include <sys/types.h>
-#include <sys/stat.h>
-#include <fcntl.h>
-#include <time.h>
-#include <errno.h>
-#include <string.h>
-
-#include "mu-util.h"
-
-#define MU_MAX_LOG_FILE_SIZE 1000 * 1000 /* 1 MB (SI units) */
-#define MU_LOG_FILE "mu.log"
-
-struct _MuLog {
-	int _fd;           /* log file descriptor */
-
-	MuLogOptions _opts;
-
-	gboolean _color_stdout;   /* whether to use color */
-	gboolean _color_stderr;
-
-	GLogFunc _old_log_func;
-};
-typedef struct _MuLog MuLog;
-
-/* we use globals, because logging is a global operation as it
- * globally modifies the behaviour of g_warning and friends
- */
-static MuLog* MU_LOG = NULL;
-static void log_write (const char* domain, GLogLevelFlags level,
-		       const gchar *msg);
-
-static void
-try_close (int fd)
-{
-	if (fd < 0)
-		return;
-
-	if (close (fd) < 0)
-		g_printerr ("%s: close() of fd %d failed: %s\n",
-				    __func__, fd, strerror(errno));
-}
-
-static void
-silence (void)
-{
-	return;
-}
-
-gboolean
-mu_log_init_silence (void)
-{
-	g_return_val_if_fail (!MU_LOG, FALSE);
-
-	MU_LOG	      = g_new0 (MuLog, 1);
-	MU_LOG->_fd   = -1;
-
-	mu_log_options_set (MU_LOG_OPTIONS_NONE);
-
-	MU_LOG->_old_log_func =
-		g_log_set_default_handler ((GLogFunc)silence, NULL);
-
-	return TRUE;
-}
-
-static void
-log_handler (const gchar* log_domain, GLogLevelFlags log_level,
-	     const gchar* msg)
-{
-	if ((log_level & G_LOG_LEVEL_DEBUG) &&
-	    !(MU_LOG->_opts & MU_LOG_OPTIONS_DEBUG))
-	 	return;
-
-	log_write (log_domain ? log_domain : "mu", log_level, msg);
-}
-
-
-void
-mu_log_options_set (MuLogOptions opts)
-{
-	g_return_if_fail (MU_LOG);
-
-	MU_LOG->_opts = opts;
-
-	/* when color is, only enable it when output is to a tty */
-	if (MU_LOG->_opts & MU_LOG_OPTIONS_COLOR) {
-		MU_LOG->_color_stdout = isatty(fileno(stdout));
-		MU_LOG->_color_stderr = isatty(fileno(stderr));
-
-	}
-}
-
-
-MuLogOptions
-mu_log_options_get (void)
-{
-	g_return_val_if_fail (MU_LOG, MU_LOG_OPTIONS_NONE);
-
-	return MU_LOG->_opts;
-}
-
-
-static gboolean
-move_log_file (const char *logfile)
-{
-	gchar *logfile_old;
-	int rv;
-
-	logfile_old = g_strdup_printf ("%s.old", logfile);
-	rv = rename (logfile, logfile_old);
-	g_free (logfile_old);
-
-	if (rv != 0) {
-		g_warning ("failed to move %s to %s.old: %s",
-			   logfile, logfile, strerror(rv));
-		return FALSE;
-	} else
-		return TRUE;
-
-}
-
-
-static gboolean
-log_file_backup_maybe (const char *logfile)
-{
-	struct stat statbuf;
-
-	if (stat (logfile, &statbuf) != 0) {
-		if (errno == ENOENT)
-			return TRUE; /* it did not exist yet, no problem */
-		else {
-			g_warning ("failed to stat(2) %s: %s",
-					   logfile, strerror(errno));
-			return FALSE;
-		}
-	}
-
-	/* log file is still below the max size? */
-	if (statbuf.st_size <= MU_MAX_LOG_FILE_SIZE)
-		return TRUE;
-
-	/* log file is too big!; we move it to <logfile>.old, overwriting */
-	return move_log_file (logfile);
-}
-
-
-gboolean
-mu_log_init (const char* logfile, MuLogOptions opts)
-{
-	int fd;
-
-	/* only init once... */
-	g_return_val_if_fail (!MU_LOG, FALSE);
-	g_return_val_if_fail (logfile, FALSE);
-
-	if (opts & MU_LOG_OPTIONS_BACKUP)
-		if (!log_file_backup_maybe(logfile)) {
-			g_warning ("failed to backup log file");
-			return FALSE;
-		}
-
-	fd = open (logfile, O_WRONLY|O_CREAT|O_APPEND, 00600);
-	if (fd < 0) {
-		g_warning ("%s: open() of '%s' failed: %s",  __func__,
-			   logfile, strerror(errno));
-		return FALSE;
-	}
-
-	MU_LOG	    = g_new0 (MuLog, 1);
-	MU_LOG->_fd = fd;
-
-	mu_log_options_set (opts);
-
-	MU_LOG->_old_log_func =
-		g_log_set_default_handler ((GLogFunc)log_handler, NULL);
-
-	MU_WRITE_LOG ("logging started");
-
-	return TRUE;
-}
-
-void
-mu_log_uninit (void)
-{
-	if (!MU_LOG)
-		return;
-
-	MU_WRITE_LOG ("logging stopped");
-
-	try_close (MU_LOG->_fd);
-	g_free (MU_LOG);
-
-	MU_LOG = NULL;
-}
-
-
-static const char*
-levelstr (GLogLevelFlags level)
-{
-	switch (level) {
-	case G_LOG_LEVEL_WARNING:  return  " [WARN] ";
-	case G_LOG_LEVEL_ERROR :   return  " [ERR ] ";
-	case G_LOG_LEVEL_DEBUG:	   return  " [DBG ] ";
-	case G_LOG_LEVEL_CRITICAL: return  " [CRIT] ";
-	case G_LOG_LEVEL_MESSAGE:  return  " [MSG ] ";
-	case G_LOG_LEVEL_INFO :	   return  " [INFO] ";
-	default:		   return  " [LOG ] ";
-	}
-}
-
-
-
-#define color_stdout_maybe(C)					    \
-	do{if (MU_LOG->_color_stdout) fputs ((C),stdout);} while (0)
-#define color_stderr_maybe(C)					    \
-	do{if (MU_LOG->_color_stderr) fputs ((C),stderr);} while (0)
-
-
-
-static void
-log_write_fd (GLogLevelFlags level, const gchar *msg)
-{
-	time_t now;
-	char timebuf [22];
-	const char *mylevel;
-
-	/* get the time/date string */
-	now = time(NULL);
-	strftime (timebuf, sizeof(timebuf), "%Y-%m-%d %H:%M:%S",
-		  localtime(&now));
-
-	if (write (MU_LOG->_fd, timebuf, strlen (timebuf)) < 0)
-		goto err;
-
-	mylevel = levelstr (level);
-	if (write (MU_LOG->_fd, mylevel, strlen (mylevel)) < 0)
-		goto err;
-
-	if (write (MU_LOG->_fd, msg, strlen (msg)) < 0)
-		goto err;
-
-	if (write (MU_LOG->_fd, "\n", strlen ("\n")) < 0)
-		goto err;
-
-	return; /* all went well */
-
-err:
-	fprintf (stderr, "%s: failed to write to log: %s\n",
-		 __func__,  strerror(errno));
-}
-
-
-static void
-log_write_stdout_stderr (GLogLevelFlags level, const gchar *msg)
-{
-	const char *mu;
-
-	mu = MU_LOG->_opts & MU_LOG_OPTIONS_NEWLINE ?
-		"\nmu: " : "mu: ";
-
-	if (!(MU_LOG->_opts & MU_LOG_OPTIONS_QUIET) &&
-	    (level & G_LOG_LEVEL_MESSAGE)) {
-		color_stdout_maybe (MU_COLOR_GREEN);
-		fputs (mu, stdout);
-		fputs (msg,    stdout);
-		fputs ("\n",   stdout);
-		color_stdout_maybe (MU_COLOR_DEFAULT);
-	}
-
-	/* for errors, log them to stderr as well */
-	if (level & G_LOG_LEVEL_ERROR ||
-	    level & G_LOG_LEVEL_CRITICAL ||
-	    level & G_LOG_LEVEL_WARNING) {
-		color_stderr_maybe (MU_COLOR_RED);
-		fputs (mu,     stderr);
-		fputs (msg,    stderr);
-		fputs ("\n",   stderr);
-		color_stderr_maybe (MU_COLOR_DEFAULT);
-	}
-}
-
-
-static void
-log_write (const char* domain, GLogLevelFlags level, const gchar *msg)
-{
-	g_return_if_fail (MU_LOG);
-
-	log_write_fd (level, msg);
-	log_write_stdout_stderr (level, msg);
-}
diff --git a/lib/utils/mu-log.h b/lib/utils/mu-log.h
deleted file mode 100644
index fc05d0b..0000000
--- a/lib/utils/mu-log.h
+++ /dev/null
@@ -1,99 +0,0 @@
-/* -*-mode: c; tab-width: 8; indent-tabs-mode: t; c-basic-offset:
-      8 -*-*/
-/*
-** Copyright (C) 2008-2013 Dirk-Jan C. Binnema <djcb@djcbsoftware.nl>
-**
-** 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 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 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.
-**
-*/
-
-#ifndef __MU_LOG_H__
-#define __MU_LOG_H__
-
-#include <glib.h>
-
-/* mu log is the global logging system */
-
-G_BEGIN_DECLS
-
-enum _MuLogOptions {
-	MU_LOG_OPTIONS_NONE	= 0,
-
-	/* when size of log file > MU_MAX_LOG_FILE_SIZE, move the log
-	 * file to <log file>.old and start a new one. The .old file will
-	 * overwrite existing files of that name */
-	MU_LOG_OPTIONS_BACKUP   = 1 << 1,
-
-	/* quiet: don't log non-errors to stdout/stderr */
-	MU_LOG_OPTIONS_QUIET    = 1 << 2,
-
-	/* should lines be preceded by \n? useful when errors come
-	 * during indexing */
-	MU_LOG_OPTIONS_NEWLINE  = 1 << 3,
-
-	/* color in output (iff output is to a tty) */
-	MU_LOG_OPTIONS_COLOR    = 1 << 4,
-
-	/* log everything to stderr */
-	MU_LOG_OPTIONS_STDERR   = 1 << 5,
-
-	/* debug: debug include debug-level information */
-	MU_LOG_OPTIONS_DEBUG    = 1 << 6
-};
-typedef enum _MuLogOptions MuLogOptions;
-
-
-/**
- * write logging information to a log file
- *
- * @param full path to the log file (does not have to exist yet, but
- * it's directory must)
- * @param opts logging options
- *
- * @return TRUE if initialization succeeds, FALSE otherwise
- */
-gboolean mu_log_init (const char *logfile, MuLogOptions opts)
-	   G_GNUC_WARN_UNUSED_RESULT;
-
-/**
- * be silent except for runtime errors, which will be written to
- * stderr.
- *
- * @return TRUE if initialization succeeds, FALSE otherwise
- */
-gboolean mu_log_init_silence    (void) G_GNUC_WARN_UNUSED_RESULT;
-
-/**
- * uninitialize the logging system, and free all resources
- */
-void mu_log_uninit             (void);
-
-/**
- * set logging options, a logical-OR'd value of MuLogOptions
- *
- * @param opts the options (logically OR'd)
- */
-void mu_log_options_set (MuLogOptions opts);
-
-/**
- * get logging options, a logical-OR'd value of MuLogOptions
- *
- * @param opts the options (logically OR'd)
- */
-MuLogOptions mu_log_options_get (void);
-
-G_END_DECLS
-
-#endif /*__MU_LOG_H__*/
diff --git a/lib/utils/mu-util.h b/lib/utils/mu-util.h
index f7147bd..071c1b4 100644
--- a/lib/utils/mu-util.h
+++ b/lib/utils/mu-util.h
@@ -309,20 +309,6 @@ typedef gpointer XapianEnquire;
 	} while (0)
 
 
-
-/**
- * log something in the log file; note, we use G_LOG_LEVEL_INFO
- * for such messages
- */
-#define MU_WRITE_LOG(...)			\
-	G_STMT_START {				\
-		g_log (G_LOG_DOMAIN,		\
-		       G_LOG_LEVEL_INFO,	\
-		       __VA_ARGS__);		\
-	} G_STMT_END
-
-
-
 #define MU_G_ERROR_CODE(GE) ((GE)&&(*(GE))?(*(GE))->code:MU_ERROR)