HexoC 语言异常处理 setjmp & longjmp 2015-09-05

#if defined(__cplusplus)
/* C++ exceptions */
#define LUAI_THROW(L,c)	throw(c)
#define LUAI_TRY(L,c,a)	try { a } catch(...) \
	{ if ((c)->status == 0) (c)->status = -1; }
#define luai_jmpbuf	int  /* dummy variable */

#elif defined(LUA_USE_ULONGJMP)
/* in Unix, try _longjmp/_setjmp (more efficient) */
#define LUAI_THROW(L,c)	_longjmp((c)->b, 1)
#define LUAI_TRY(L,c,a)	if (_setjmp((c)->b) == 0) { a }
#define luai_jmpbuf	jmp_buf

#else
/* default handling with long jumps */
#define LUAI_THROW(L,c)	longjmp((c)->b, 1)
#define LUAI_TRY(L,c,a)	if (setjmp((c)->b) == 0) { a }
#define luai_jmpbuf	jmp_buf

#endif

do 
{
    jmp_buf __buf;

    /**
     * setting exceptions handling
     */
    switch(setjmp(__buf))
    {
        case 0                : /* do nothing */ break;
        case EXCEPTION_TYPE_1 : /* exception handle */ break;
        case EXCEPTION_TYPE_2 : /* exception handle */ break;
        case EXCEPTION_TYPE_3 : /* exception handle */ break;
        .
        .
        .
        default               : /* final */ break;
    }

    /**
     * there are some try blocks
     */
    {
        //BLOCK CODES

        /**
         * throw a exception
         */
        longjmp(__buf, EXCEPTION_TYPE_VALUE);
    }

} while(0);