Initially add small and tight logging facility

src/CMakeLists.txt

@@ -90,6 +90,7 @@ configure_file(
 )
 
 set(common_SRCS
+	log.cpp
 	content_sao.cpp
 	mapgen.cpp
 	content_inventory.cpp

src/log.cpp

+/*
+Minetest-c55
+Copyright (C) 2011 celeron55, Perttu Ahola <celeron55@gmail.com>
+
+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 "log.h"
+
+#include <map>
+#include <list>
+#include <sstream>
+#include "threads.h"
+#include "debug.h"
+#include "gettime.h"
+
+std::list<ILogOutput*> log_outputs[LMT_NUM_VALUES];
+std::map<threadid_t, std::string> log_threadnames;
+
+void log_add_output(ILogOutput *out, enum LogMessageLevel lev)
+{
+	log_outputs[lev].push_back(out);
+}
+
+void log_add_output_maxlev(ILogOutput *out, enum LogMessageLevel lev)
+{
+	for(int i=0; i<=lev; i++)
+		log_outputs[i].push_back(out);
+}
+
+void log_add_output_all_levs(ILogOutput *out)
+{
+	for(int i=0; i<LMT_NUM_VALUES; i++)
+		log_outputs[i].push_back(out);
+}
+
+void log_register_thread(const std::string &name)
+{
+	threadid_t id = get_current_thread_id();
+	log_threadnames[id] = name;
+}
+
+static std::string get_lev_string(enum LogMessageLevel lev)
+{
+	switch(lev){
+	case LMT_ERROR:
+		return "ERROR";
+	case LMT_ACTION:
+		return "ACTION";
+	case LMT_INFO:
+		return "INFO";
+	case LMT_VERBOSE:
+		return "VERBOSE";
+	case LMT_NUM_VALUES:
+		break;
+	}
+	return "(unknown level)";
+}
+
+void log_printline(enum LogMessageLevel lev, const std::string &text)
+{
+	std::string threadname = "(unknown thread)";
+	std::map<threadid_t, std::string>::const_iterator i;
+	i = log_threadnames.find(get_current_thread_id());
+	if(i != log_threadnames.end())
+		threadname = i->second;
+	std::string levelname = get_lev_string(lev);
+	std::ostringstream os(std::ios_base::binary);
+	os<<getTimestamp()<<": "<<levelname<<"["<<threadname<<"]: "<<text;
+	for(std::list<ILogOutput*>::iterator i = log_outputs[lev].begin();
+			i != log_outputs[lev].end(); i++){
+		ILogOutput *out = *i;
+		out->printLog(os.str());
+		out->printLog(lev, text);
+	}
+}
+
+class Logbuf : public std::streambuf
+{
+public:
+	Logbuf(enum LogMessageLevel lev):
+		m_lev(lev)
+	{
+	}
+
+	~Logbuf()
+	{
+	}
+
+	int overflow(int c)
+	{
+		bufchar(c);
+		return c;
+	}
+	std::streamsize xsputn(const char *s, std::streamsize n)
+	{
+		for(int i=0; i<n; i++)
+			bufchar(s[i]);
+		return n;
+	}
+
+	void printbuf()
+	{
+		log_printline(m_lev, m_buf);
+	}
+
+	void bufchar(char c)
+	{
+		if(c == '\n' || c == '\r'){
+			if(m_buf != "")
+				printbuf();
+			m_buf = "";
+			return;
+		}
+		m_buf += c;
+	}
+	
+private:
+	enum LogMessageLevel m_lev;
+	std::string m_buf;
+};
+
+Logbuf errorbuf(LMT_ERROR);
+Logbuf actionbuf(LMT_ACTION);
+Logbuf infobuf(LMT_INFO);
+Logbuf verbosebuf(LMT_VERBOSE);
+std::ostream errorstream(&errorbuf);
+std::ostream actionstream(&actionbuf);
+std::ostream infostream(&infobuf);
+std::ostream verbosestream(&verbosebuf);
+
+

src/log.h

+/*
+Minetest-c55
+Copyright (C) 2011 celeron55, Perttu Ahola <celeron55@gmail.com>
+
+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 LOG_HEADER
+#define LOG_HEADER
+
+#include <string>
+
+/*
+	Use this for logging everything.
+	
+	If you need to explicitly print something, use dstream or cout or cerr.
+*/
+
+enum LogMessageLevel {
+	LMT_ERROR, /* Something failed ("invalid map data on disk, block (2,2,1)") */
+	LMT_ACTION, /* In-game actions ("celeron55 placed block at (12,4,-5)") */
+	LMT_INFO, /* More deep info ("saving map on disk (only_modified=true)") */
+	LMT_VERBOSE, /* Flood-style ("loaded block (2,2,2) from disk") */
+	LMT_NUM_VALUES,
+};
+
+class ILogOutput
+{
+public:
+	/* line: Full line with timestamp, level and thread */
+	virtual void printLog(const std::string &line){};
+	/* line: Only actual printed text */
+	virtual void printLog(enum LogMessageLevel lev, const std::string &line){};
+};
+
+void log_add_output(ILogOutput *out, enum LogMessageLevel lev);
+void log_add_output_maxlev(ILogOutput *out, enum LogMessageLevel lev);
+void log_add_output_all_levs(ILogOutput *out);
+
+void log_register_thread(const std::string &name);
+
+void log_printline(enum LogMessageLevel lev, const std::string &text);
+
+#define LOGLINEF(lev, ...)\
+{\
+	char buf[10000];\
+	snprintf(buf, 10000, __VA_ARGS__);\
+	log_printline(lev, buf);\
+}
+
+extern std::ostream errorstream;
+extern std::ostream actionstream;
+extern std::ostream infostream;
+extern std::ostream verbosestream;
+
+#endif
+