/*

    信号异常处理;

	by dzj, 09.08.14

	ref:http://www.ibm.com/developerworks/cn/linux/l-cppexcep.html 'linux下c++异常处理技巧'
	    disclosed anonymously 'method for extended c++ exception features to handle OS signal exceptions'
		'unix 环境高级编程'.sigsetjmp&siglongjmp
*/

#ifndef DS_SIG_EXCEPT
#define DS_SIG_EXCEPT

#ifndef WIN32
#include <execinfo.h>
#endif //WIN32

#include <signal.h>
#include <exception>

#include "../dslock.h"
#include "../buflog.h"

using namespace std;

//#ifndef WIN32
//#include <setjmp.h>
////static sigjmp_buf* g_pJmpbuf = NULL;//全局跳转缓存；
////static volatile sig_atomic_t canjmp;
//#endif //WIN32

//主干版本不使用，#define USE_SIG_TRY //使用信号转异常处理；
#define USE_SIG_TRY //主干也开开，效率比原来更高点，也充分测试下这些异常处理代码，by dzj, 09.10.15;

#ifdef USE_SIG_TRY
		extern bool g_isException;

		#ifdef WIN32
			#define DS_TRY_BEGIN { try {
		#else  //WIN32
			#define DS_TRY_BEGIN \
				{ \
				sigjmp_buf* oldjmpbuf = NULL; bool isoldbufvalid = false;\
				GET_TLS_SIGEXCEPTBUF( oldjmpbuf, isoldbufvalid ); \
				if ( !isoldbufvalid )\
		        {\
				    printf( "DS_TRY_BEGIN, invalid oldjumpbuf\n" );\
		            while(true);/*不可能错误, by dzj, 10.04.01*/\
		        }\
				sigjmp_buf* newjmpbuf = new sigjmp_buf[sizeof(sigjmp_buf)/sizeof(__jmp_buf_tag)]; bool isnewbufset = false; \
				SET_TLS_SIGEXCEPTBUF( newjmpbuf, isnewbufset );\
				if ( !isnewbufset )\
		        {\
				    printf( "DS_TRY_BEGIN, can not set newjmpbuf\n" );\
		            while(true);/*不可能错误, by dzj, 10.04.01*/\
		        }\
				try { \
					int jmprst = sigsetjmp( *newjmpbuf, 1/*restore signal mask*/ ); \
					if ( 0 != jmprst ) \
					{ \
					/*使用buflog,buflog中不使用信号异常捕捉，cout << "return from signal handle, rst : "<< jmprst << endl; 从信号处理函数中longjump回来；*/\
					NewLog( LOG_LEV_ERROR, "return from signal handle, : %d", jmprst );\
					throw jmprst; \
					}
		#endif //WIN32

			#define DS_CATCH_SIG \
				} catch ( int signalid ) { \
					/*使用buflog,buflog中不使用信号异常捕捉，cout << "catch by sigsetjmp, signal:" << signalid << endl; */\
					NewLog( LOG_LEV_ERROR, "catch by sigsetjmp, signal: %d", signalid );\
					g_isException = true;

			#define DS_CATCH_NORMAL \
				} catch (...) { \
					/*使用buflog,buflog中不使用信号异常捕捉，cout << "exception catched!" << endl;*/\
					NewLog( LOG_LEV_ERROR, "exception catched!" );\
					g_isException = true;

		#ifdef WIN32
			#define DS_END_TRY \
					}\
				}
		#else  //WIN32
			#define DS_END_TRY \
					}\
					bool isoldbufset = false;\
					SET_TLS_SIGEXCEPTBUF( oldjmpbuf, isoldbufset );\
					if ( !isoldbufset )\
					{\
						printf( "DS_END_TRY, can not set oldjmpbuf\n" );\
						while(true);/*不可能错误, by dzj, 10.04.01*/\
					}\
					delete [] newjmpbuf; newjmpbuf = NULL; \
				}
		#endif //WIN32

        #define ST_SIG_CATCH DS_TRY_BEGIN {
        #define END_SIG_CATCH \
					} DS_CATCH_SIG { \
						NewLog( LOG_LEV_DEBUG, "DS_CATCH_SIG" );\
					} DS_CATCH_NORMAL {\
						NewLog( LOG_LEV_DEBUG, "DS_CATCH_NORMAL" );\
					} DS_END_TRY;
#else  //USE_SIG_TRY

		#define DS_TRY_BEGIN 
		#define DS_CATCH_SIG 
		#define DS_CATCH_NORMAL
		#define DS_END_TRY 

        #define ST_SIG_CATCH 
        #define END_SIG_CATCH 

#endif //USE_SIG_TRY

class ExceptionTracer
{
public:
	ExceptionTracer()
	{
#ifndef WIN32
		void* array1[25];
		int nSize = backtrace( array1, 25 );
		char** symbols = backtrace_symbols( array1, nSize);
		for ( int i=0; i<nSize; ++i )
		{
			cout << symbols[i] << endl;
		}
		free( symbols );
#endif //WIN32
	}
};

template <class SignalExceptionClass> class SignalTranslator
{
private:
	class SingleTonTranslator
	{
	public:
		SingleTonTranslator()
		{
			signal( SignalExceptionClass::GetSignalNumber(), SignalHandler );
		}

		static void SignalHandler( int signo )
		{
			//使用buflog,buflog中不使用信号异常捕捉，cout << "in SignalHandler:" << signo << endl;
			NewLog( LOG_LEV_ERROR, "in SignalHandler : %d", signo );
#ifdef WIN32
			throw SignalExceptionClass();
#else  //WIN32
			{
				void* array1[25];
				int nSize = backtrace( array1, 25 );
				char** symbols = backtrace_symbols( array1, nSize);
				for ( int i=0; i<nSize; ++i )
				{
					//使用buflog,buflog中不使用信号异常捕捉，cout << "BT:" << symbols[i] << endl;
					NewLog( LOG_LEV_ERROR, "BT : %s", symbols[i] );
				}
				free( symbols );
			}
			//if ( 0 == canjmp )
#ifdef USE_SIG_TRY
			sigjmp_buf* jmpbuf = NULL; bool isgetok = false;
			GET_TLS_SIGEXCEPTBUF( jmpbuf, isgetok );
			if ( isgetok && (NULL != jmpbuf) )
#else  //USE_SIG_TRY
			if ( false )
#endif //USE_SIG_TRY
			{
				siglongjmp( *jmpbuf, signo );
			} else {
				//使用buflog,buflog中不使用信号异常捕捉，cout << "!!! unprepared signal : " << signo << endl;
				NewLog( LOG_LEV_ERROR, "!!! unprepared signal : %d", signo );
				return;
			}
#endif //WIN32
		}
	};

public:
	SignalTranslator()
	{
		static SingleTonTranslator s_objTranslator;
	}
};

class SegmentationFault : public ExceptionTracer, public exception
{
public:
	static inline int GetSignalNumber() { return SIGSEGV; }
};
extern SignalTranslator<SegmentationFault> g_objSegmentationFaultTranslator;

class AbortSig : public ExceptionTracer, public exception
{
public:
	static inline int GetSignalNumber() { return SIGABRT; }
};
extern SignalTranslator<AbortSig> g_objAbortSigTranslator;


#ifndef WIN32
class BusFault : public ExceptionTracer, public exception
{
public:
	static inline int GetSignalNumber() { return SIGBUS; }
};
extern SignalTranslator<BusFault> g_objBusFaultTranslator;
#endif //WIN32

class FloatingPointException : public ExceptionTracer, public exception
{
public:
	static inline int GetSignalNumber() { return SIGFPE; }
};
extern SignalTranslator<FloatingPointException> g_objFloatingPointExceptionTranslator;

#endif  //DS_SIG_EXCEPT