LogInit: move backend code to LogBackend.cxx

Makefile.am

@@ -147,7 +147,7 @@ src_mpd_SOURCES = \
 	src/ClientFile.cxx src/ClientFile.hxx \
 	src/Listen.cxx src/Listen.hxx \
 	src/LogInit.cxx src/LogInit.hxx \
-	src/LogBackend.cxx \
+	src/LogBackend.cxx src/LogBackend.hxx \
 	src/Log.cxx src/Log.hxx src/LogV.hxx \
 	src/LogLevel.hxx \
 	src/ls.cxx src/ls.hxx \

src/LogBackend.cxx

@@ -18,37 +18,162 @@
  */
 
 #include "config.h"
+#include "LogBackend.hxx"
 #include "Log.hxx"
 #include "util/Domain.hxx"
+#include "util/CharUtil.hxx"
 
 #include <glib.h>
 
 #include <assert.h>
+#include <stdio.h>
+#include <string.h>
 
-static GLogLevelFlags
-ToGLib(LogLevel level)
+#ifdef HAVE_SYSLOG
+#include <syslog.h>
+#endif
+
+static LogLevel log_threshold = LogLevel::INFO;
+static const char *log_charset;
+
+static bool enable_timestamp;
+
+#ifdef HAVE_SYSLOG
+static bool enable_syslog;
+#endif
+
+void
+SetLogThreshold(LogLevel _threshold)
+{
+	log_threshold = _threshold;
+}
+
+void
+SetLogCharset(const char *_charset)
+{
+	log_charset = _charset;
+}
+
+void
+EnableLogTimestamp()
 {
-	switch (level) {
+#ifdef HAVE_SYSLOG
+	assert(!enable_syslog);
+#endif
+	assert(!enable_timestamp);
+
+	enable_timestamp = true;
+}
+
+static const char *log_date(void)
+{
+	static constexpr size_t LOG_DATE_BUF_SIZE = 16;
+	static char buf[LOG_DATE_BUF_SIZE];
+	time_t t = time(nullptr);
+	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 && IsWhitespaceOrNull(p[length - 1]))
+		--length;
+
+	return (int)length;
+}
+
+#ifdef HAVE_SYSLOG
+
+static int
+ToSysLogLevel(LogLevel log_level)
+{
+	switch (log_level) {
 	case LogLevel::DEBUG:
-		return G_LOG_LEVEL_DEBUG;
+		return LOG_DEBUG;
 
 	case LogLevel::INFO:
-		return G_LOG_LEVEL_INFO;
+		return LOG_INFO;
 
 	case LogLevel::DEFAULT:
-		return G_LOG_LEVEL_MESSAGE;
+		return LOG_NOTICE;
 
 	case LogLevel::WARNING:
+		return LOG_WARNING;
+
 	case LogLevel::ERROR:
-		return G_LOG_LEVEL_WARNING;
+		return LOG_ERR;
 	}
 
 	assert(false);
 	gcc_unreachable();
 }
 
+static void
+SysLog(const Domain &domain, LogLevel log_level, const char *message)
+{
+	syslog(ToSysLogLevel(log_level), "%s: %.*s",
+	       domain.GetName(),
+	       chomp_length(message), message);
+}
+
+void
+LogInitSysLog()
+{
+	openlog(PACKAGE, 0, LOG_DAEMON);
+	enable_syslog = true;
+}
+
+void
+LogFinishSysLog()
+{
+	if (enable_syslog)
+		closelog();
+}
+
+#endif
+
+static void
+FileLog(const Domain &domain, const char *message)
+{
+	char *converted;
+
+	if (log_charset != nullptr) {
+		converted = g_convert_with_fallback(message, -1,
+						    log_charset, "utf-8",
+						    nullptr, nullptr,
+						    nullptr, nullptr);
+		if (converted != nullptr)
+			message = converted;
+	} else
+		converted = nullptr;
+
+	fprintf(stderr, "%s%s: %.*s\n",
+		enable_timestamp ? log_date() : "",
+		domain.GetName(),
+		chomp_length(message), message);
+
+	g_free(converted);
+}
+
 void
 Log(const Domain &domain, LogLevel level, const char *msg)
 {
-	g_log(domain.GetName(), ToGLib(level), "%s", msg);
+	if (level < log_threshold)
+		return;
+
+#ifdef HAVE_SYSLOG
+	if (enable_syslog) {
+		SysLog(domain, level, msg);
+		return;
+	}
+#endif
+
+	FileLog(domain, msg);
 }

src/LogBackend.hxx

+/*
+ * Copyright (C) 2003-2013 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.
+ */
+
+#ifndef MPD_LOG_BACKEND_HXX
+#define MPD_LOG_BACKEND_HXX
+
+#include "LogLevel.hxx"
+
+void
+SetLogThreshold(LogLevel _threshold);
+
+void
+SetLogCharset(const char *_charset);
+
+void
+EnableLogTimestamp();
+
+void
+LogInitSysLog();
+
+void
+LogFinishSysLog();
+
+#endif /* LOG_H */

src/LogInit.cxx

@@ -19,6 +19,7 @@
 
 #include "config.h"
 #include "LogInit.hxx"
+#include "LogBackend.hxx"
 #include "Log.hxx"
 #include "ConfigData.hxx"
 #include "ConfigGlobal.hxx"
@@ -28,7 +29,6 @@
 #include "fs/FileSystem.hxx"
 #include "util/Error.hxx"
 #include "util/Domain.hxx"
-#include "util/CharUtil.hxx"
 #include "system/FatalError.hxx"
 
 #include <assert.h>
@@ -39,22 +39,13 @@
 #include <unistd.h>
 #include <glib.h>
 
-#ifdef HAVE_SYSLOG
-#include <syslog.h>
-#endif
-
-#define LOG_LEVEL_SECURE G_LOG_LEVEL_INFO
+#define LOG_LEVEL_SECURE LogLevel::INFO
 
 #define LOG_DATE_BUF_SIZE 16
 #define LOG_DATE_LEN (LOG_DATE_BUF_SIZE - 1)
 
 static constexpr Domain log_domain("log");
 
-static GLogLevelFlags log_threshold = G_LOG_LEVEL_MESSAGE;
-
-static const char *log_charset;
-
-static bool stdout_mode = true;
 static int out_fd;
 static AllocatedPath out_path = AllocatedPath::Null();
 
@@ -67,66 +58,6 @@ static void redirect_logs(int fd)
 		FatalSystemError("Failed to dup2 stderr");
 }
 
-static const char *log_date(void)
-{
-	static char buf[LOG_DATE_BUF_SIZE];
-	time_t t = time(nullptr);
-	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 && IsWhitespaceOrNull(p[length - 1]))
-		--length;
-
-	return (int)length;
-}
-
-static void
-file_log_func(const gchar *domain,
-	      GLogLevelFlags log_level,
-	      const gchar *message, gcc_unused gpointer user_data)
-{
-	char *converted;
-
-	if (log_level > log_threshold)
-		return;
-
-	if (log_charset != nullptr) {
-		converted = g_convert_with_fallback(message, -1,
-						    log_charset, "utf-8",
-						    nullptr, nullptr,
-						    nullptr, nullptr);
-		if (converted != nullptr)
-			message = converted;
-	} else
-		converted = nullptr;
-
-	if (domain == nullptr)
-		domain = "";
-
-	fprintf(stderr, "%s%s%s%.*s\n",
-		stdout_mode ? "" : log_date(),
-		domain, *domain == 0 ? "" : ": ",
-		chomp_length(message), message);
-
-	g_free(converted);
-}
-
-static void
-log_init_stdout(void)
-{
-	g_log_set_default_handler(file_log_func, nullptr);
-}
-
 static int
 open_log_file(void)
 {
@@ -148,85 +79,22 @@ log_init_file(unsigned line, Error &error)
 		return false;
 	}
 
-	g_log_set_default_handler(file_log_func, nullptr);
+	EnableLogTimestamp();
 	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 *domain,
-		GLogLevelFlags log_level, const gchar *message,
-		gcc_unused gpointer user_data)
-{
-	if (stdout_mode) {
-		/* fall back to the file log function during
-		   startup */
-		file_log_func(domain, log_level,
-			      message, user_data);
-		return;
-	}
-
-	if (log_level > log_threshold)
-		return;
-
-	if (domain == nullptr)
-		domain = "";
-
-	syslog(glib_to_syslog_level(log_level), "%s%s%.*s",
-	       domain, *domain == 0 ? "" : ": ",
-	       chomp_length(message), message);
-}
-
-static void
-log_init_syslog(void)
-{
-	assert(out_path.IsNull());
-
-	openlog(PACKAGE, 0, LOG_DAEMON);
-	g_log_set_default_handler(syslog_log_func, nullptr);
-}
-
-#endif
-
-static inline GLogLevelFlags
+static inline LogLevel
 parse_log_level(const char *value, unsigned line)
 {
 	if (0 == strcmp(value, "default"))
-		return G_LOG_LEVEL_MESSAGE;
+		return LogLevel::DEFAULT;
 	if (0 == strcmp(value, "secure"))
 		return LOG_LEVEL_SECURE;
 	else if (0 == strcmp(value, "verbose"))
-		return G_LOG_LEVEL_DEBUG;
+		return LogLevel::DEBUG;
 	else {
 		FormatFatalError("unknown log level \"%s\" at line %u",
 				 value, line);
-		return G_LOG_LEVEL_MESSAGE;
 	}
 }
 
@@ -234,9 +102,7 @@ void
 log_early_init(bool verbose)
 {
 	if (verbose)
-		log_threshold = G_LOG_LEVEL_DEBUG;
-
-	log_init_stdout();
+		SetLogThreshold(LogLevel::DEBUG);
 }
 
 bool
@@ -244,16 +110,17 @@ log_init(bool verbose, bool use_stdout, Error &error)
 {
 	const struct config_param *param;
 
-	g_get_charset(&log_charset);
+	const char *charset;
+	g_get_charset(&charset);
+	SetLogCharset(charset);
 
 	if (verbose)
-		log_threshold = G_LOG_LEVEL_DEBUG;
+		SetLogThreshold(LogLevel::DEBUG);
 	else if ((param = config_get_param(CONF_LOG_LEVEL)) != nullptr)
-		log_threshold = parse_log_level(param->value.c_str(),
-						param->line);
+		SetLogThreshold(parse_log_level(param->value.c_str(),
+						param->line));
 
 	if (use_stdout) {
-		log_init_stdout();
 		return true;
 	} else {
 		param = config_get_param(CONF_LOG_FILE);
@@ -261,7 +128,7 @@ log_init(bool verbose, bool use_stdout, Error &error)
 #ifdef HAVE_SYSLOG
 			/* no configuration: default to syslog (if
 			   available) */
-			log_init_syslog();
+			LogInitSysLog();
 			return true;
 #else
 			error.Set(log_domain,
@@ -270,7 +137,7 @@ log_init(bool verbose, bool use_stdout, Error &error)
 #endif
 #ifdef HAVE_SYSLOG
 		} else if (strcmp(param->value.c_str(), "syslog") == 0) {
-			log_init_syslog();
+			LogInitSysLog();
 			return true;
 #endif
 		} else {
@@ -284,12 +151,8 @@ log_init(bool verbose, bool use_stdout, Error &error)
 static void
 close_log_files(void)
 {
-	if (stdout_mode)
-		return;
-
 #ifdef HAVE_SYSLOG
-	if (out_path.IsNull())
-		closelog();
+	LogFinishSysLog();
 #endif
 }
 
@@ -303,32 +166,35 @@ log_deinit(void)
 
 void setup_log_output(bool use_stdout)
 {
+	if (use_stdout)
+		return;
+
 	fflush(nullptr);
-	if (!use_stdout) {
-#ifndef WIN32
-		if (out_path.IsNull())
+
+	if (out_fd < 0) {
+#ifdef WIN32
+		return;
+#else
 		out_fd = open("/dev/null", O_WRONLY);
+		if (out_fd < 0)
+			return;
 #endif
+	}
 
-		if (out_fd >= 0) {
 	redirect_logs(out_fd);
 	close(out_fd);
-		}
+	out_fd = -1;
 
-		stdout_mode = false;
-		log_charset = nullptr;
-	}
+	SetLogCharset(nullptr);
 }
 
 int cycle_log_files(void)
 {
 	int fd;
 
-	if (stdout_mode || out_path.IsNull())
+	if (out_path.IsNull())
 		return 0;
 
-	assert(!out_path.IsNull());
-
 	FormatDebug(log_domain, "Cycling log files");
 	close_log_files();