纯c实现异常捕获try-catch组件教程示例

2022-08-07 18:54:16
目录
try / catch / finally / throw 介绍如何实现try-catch这一机制?setjmp/longjmp使用介绍(重点)try-catch 和 setjmp/longjmp 的关系宏定义实现try-catch Demo实现try-catch的三个问题1. 在哪个文件哪个函数哪个行抛的异常2. try-catch嵌套怎么做?3. try-catch线程安全代码实现与解释trythrowCatchFinallyEndTrytry-catch代码Debug测试代码线程安全、try-catch、Debug测试代码 汇总

try>

本文用纯c的代码,实现异常捕获try-catch组件。阅读本文需要时刻牢记setjmp和longjmp的对应关系。

在java,python,c++里面都有try catch异常捕获。在try代码块里面执行的函数,如果出错有异常了,就会throw把异常抛出来,抛出来的异常被catch接收进行处理,而finally意味着无论有没有异常,都会执行finally代码块内的代码。

try{
    connect_sql();//throw
}catch(){
}finally {
};

如何实现try-catch这一机制?

关于跳转,有两个跳转。那么在这里我们必然选用长跳转。

    goto:函数内跳转,短跳转setjmp/longjmp:跨函数跳转,长跳转

    setjmp/longjmp这两个函数是不存在压栈出栈的,也就是说longjmp跳转到setjmp的地方后,会覆盖之前的栈。

    setjmp/longjmp使用介绍(重点)

      setjmp(env):设置跳转的位置,第一次返回0,后续返回longjmp的第二个参数longjmp(env,>
      #include <stdio.h>
      #include <setjmp.h>
      jmp_buf env;
      int count = 0;
      void sub_func(int idx) {
          printf("sub_func -->idx : %d\n", idx);
          //第二个参数就是setjmp()的返回值
          longjmp(env, idx);
      }
      int main() {
          int idx = 0;
          //设置跳转标签,第一次返回0
          count = setjmp(env);
          if (count == 0) {
              printf("count : %d\n", count);
              sub_func(++idx);
          }
          else if (count == 1) {
              printf("count : %d\n", count);
              sub_func(++idx);
          }
          else if (count == 2) {
              printf("count : %d\n", count);
              sub_func(++idx);
          }
          else {
              printf("other count \n");
          }
          return 0;
      }
      
      count : 0
      sub_func -->idx : 1
      count : 1
      sub_func -->idx : 2
      count : 2
      sub_func -->idx : 3
      other count 
      

      try-catch>
      try ---&gt; setjmp(env)
      throw ---&gt; longjmp(env,Exception)
      catch(Exception)
      

      我们其实可以分析出来,setjmp和count==0的地方,相当于try,后面的else if 相当于catch,最后一个else,其实并不是finally,因为finally是不管怎么样都会执行,上图我标注的其实是误导的。应该是下图这样才对。

      宏定义实现try-catch>

      4个关键字分析出来它们的关系之后,其实我们就能用宏定义来实现了。

      #include <stdio.h>
      #include <setjmp.h>
      typedef struct _Exception {
          jmp_buf env;
          int exceptype;
      } Exception;
      #define Try(excep) if((excep.exceptype=setjmp(excep.env))==0)
      #define Catch(excep, ExcepType) else if(excep.exceptype==ExcepType)
      #define Throw(excep, ExcepType) longjmp(excep.env,ExcepType)
      #define Finally
      void throw_func(Exception ex, int idx) {
          printf("throw_func -->idx : %d\n", idx);
          Throw(ex, idx);
      }
      int main() {
          int idx = 0;
          Exception ex;
          Try(ex) {
              printf("ex.exceptype : %d\n", ex.exceptype);
              throw_func(ex, ++idx);
          }
          Catch(ex, 1) {
              printf("ex.exceptype : %d\n", ex.exceptype);
          }
          Catch(ex, 2) {
              printf("ex.exceptype : %d\n", ex.exceptype);
          }
          Catch(ex, 3) {
              printf("ex.exceptype : %d\n", ex.exceptype);
          }
          Finally{
              printf("Finally\n");
          };
          return 0;
      }
      
      ex.exceptype : 0
      throw_func -->idx : 1
      ex.exceptype : 1
      Finally
      

      实现try-catch的三个问题

      虽然现在demo版看起来像这么回事了,但是还是有两个问题:

        在哪个文件哪个函数哪个行抛的异常?try-catch嵌套怎么做?try-catch线程安全怎么做?

        1.>

        系统提供了三个宏可以供我们使用,如果我们没有catch到异常,我们就可以打印出来

        __func__, __FILE__, __LINE__

        2.>

        我们知道try-catch是可以嵌套的,那么这就形成了一个栈的数据结构,现在下面有三个try,每个setjmp对应的都是不同的jmp_buf,那么我们可以定义一个jmp_buf的栈。

        try{
            try{
                try{
                }catch(){
                }
            }catch(){
            }
        }catch(){
        }finally{
        };
        

        那么我们很容易能写出来,既然是栈,try的时候我们就插入一个结点,catch的时候我们就pop一个出来。

        #define EXCEPTION_MESSAGE_LENGTH                512
        typedef struct _ntyException {
            const char *name;
        } ntyException;
        ntyException SQLException = {"SQLException"};
        ntyException TimeoutException = {"TimeoutException"};
        typedef struct _ntyExceptionFrame {
            jmp_buf env;
            int line;
            const char *func;
            const char *file;
            ntyException *exception;
            struct _ntyExceptionFrame *next;
            char message[EXCEPTION_MESSAGE_LENGTH + 1];
        } ntyExceptionFrame;
        enum {
            ExceptionEntered = 0,//0
            ExceptionThrown,    //1
            ExceptionHandled, //2
            ExceptionFinalized//3
        };
        

        3.>

        每个线程都可以try-catch,但是我们以及知道了是个栈结构,既ExceptionStack,那么每个线程是独有一个ExceptionStack呢?还是共享同一个ExceptionStack?很明显,A线程的异常应该有A的处理,而不是由B线程处理。那么我们就使用Linux线程私有数据Thread-specific Data(TSD)来做。

        /* ** **** ******** **************** Thread safety **************** ******** **** ** */
        #define ntyThreadLocalData                      pthread_key_t
        #define ntyThreadLocalDataSet(key, value)       pthread_setspecific((key), (value))
        #define ntyThreadLocalDataGet(key)              pthread_getspecific((key))
        #define ntyThreadLocalDataCreate(key)           pthread_key_create(&(key), NULL)
        ntyThreadLocalData ExceptionStack;
        static void init_once(void) {
            ntyThreadLocalDataCreate(ExceptionStack);
        }
        static pthread_once_t once_control = PTHREAD_ONCE_INIT;
        void ntyExceptionInit(void) {
            pthread_once(&once_control, init_once);
        }
        

        代码实现与解释

        try

        首先创建一个新节点入栈,然后setjmp设置一个标记,接下来就是大括号里面的操作了,如果有异常,那么就会被throw抛出来,为什么这里最后一行是if?因为longjmp的时候,返回的地方是setjmp,不要忘了!要时刻扣住longjmp和setjmp。

        #define Try do {                                                                        \
                    volatile int Exception_flag;                                                \
                    ntyExceptionFrame frame;                                                    \
                    frame.message[0] = 0;                                                       \
                    frame.next = (ntyExceptionFrame*)ntyThreadLocalDataGet(ExceptionStack);     \
                    ntyThreadLocalDataSet(ExceptionStack, &frame);                              \
                    Exception_flag = setjmp(frame.env);                                         \
                    if (Exception_flag == ExceptionEntered) {
        
        Try{
        	//...
            Throw(A, "A");
        }
        

        throw

        在这里,我们不应该把throw定义成宏,而应该定义成函数。这里分两类,一类是try里面的throw,一类是没有try直接throw。

          对于try里面的异常,我们将其状态变成ExceptionThrown,然后longjmp到setjmp的地方,由catch处理对于直接抛的异常,必然没有catch去捕获,那么我们直接打印出来如果第一种情况的异常,没有被catch捕获到怎么办呢?后面会被ReThrow出来,对于再次被抛出,我们就直接进行打印异常

          这里的##__VA_ARGS__是可变参数,具体不多介绍了,不是本文重点。

          #define ReThrow                    ntyExceptionThrow(frame.exception, frame.func, frame.file, frame.line, NULL)
          #define Throw(e, cause, ...)    ntyExceptionThrow(&amp;(e), __func__, __FILE__, __LINE__, cause, ##__VA_ARGS__,NULL)
          
          void ntyExceptionThrow(ntyException *excep, const char *func, const char *file, int line, const char *cause, ...) {
              va_list ap;
              ntyExceptionFrame *frame = (ntyExceptionFrame *) ntyThreadLocalDataGet(ExceptionStack);
              if (frame) {
                  //异常名
                  frame->exception = excep;
                  frame->func = func;
                  frame->file = file;
                  frame->line = line;
                  //异常打印的信息
                  if (cause) {
                      va_start(ap, cause);
                      vsnprintf(frame->message, EXCEPTION_MESSAGE_LENGTH, cause, ap);
                      va_end(ap);
                  }
                  ntyExceptionPopStack;
                  longjmp(frame->env, ExceptionThrown);
              }
                  //没有被catch,直接throw
              else if (cause) {
                  char message[EXCEPTION_MESSAGE_LENGTH + 1];
                  va_start(ap, cause);
                  vsnprintf(message, EXCEPTION_MESSAGE_LENGTH, cause, ap);
                  va_end(ap);
                  printf("%s: %s\n raised in %s at %s:%d\n", excep->name, message, func ? func : "?", file ? file : "?", line);
              }
              else {
                  printf("%s: %p\n raised in %s at %s:%d\n", excep->name, excep, func ? func : "?", file ? file : "?", line);
              }
          }
          

          Catch

          如果还是ExceptionEntered状态,说明没有异常,没有throw。如果捕获到异常了,那么其状态就是ExceptionHandled。

          #define Catch(nty_exception) \
                          if (Exception_flag == ExceptionEntered) ntyExceptionPopStack; \
                      } else if (frame.exception == &(nty_exception)) { \
                          Exception_flag = ExceptionHandled;
          

          Finally

          finally也是一样,如果还是ExceptionEntered状态,说明没有异常没有捕获,那么现在状态是终止阶段。

          #define Finally \
                          if (Exception_flag == ExceptionEntered) ntyExceptionPopStack; \
                      } { \
                          if (Exception_flag == ExceptionEntered)    \
                              Exception_flag = ExceptionFinalized;
          

          EndTry

          有些人看到EndTry可能会有疑问,try-catch一共不就4个关键字吗?怎么你多了一个。我们先来看看EndTry做了什么,首先如果是ExceptionEntered状态,那意味着什么?意味着没有throw,没有catch,没有finally,只有try,我们需要对这种情况进行处理,要出栈。

          还有一种情况,如果是ExceptionThrown状态,说明什么?没有被catch捕获到,那么我们就再次抛出,进行打印错误。至于为什么多个EndTry,写起来方便呗~

          #define EndTry \
                          if (Exception_flag == ExceptionEntered) ntyExceptionPopStack; \
                      } if (Exception_flag == ExceptionThrown) {ReThrow;} \
                      } while (0)
          

          try-catch代码

          /* ** **** ******** **************** try / catch / finally / throw **************** ******** **** ** */
          #define EXCEPTION_MESSAGE_LENGTH                512
          typedef struct _ntyException {
              const char *name;
          } ntyException;
          ntyException SQLException = {"SQLException"};
          ntyException TimeoutException = {"TimeoutException"};
          typedef struct _ntyExceptionFrame {
              jmp_buf env;
              int line;
              const char *func;
              const char *file;
              ntyException *exception;
              struct _ntyExceptionFrame *next;
              char message[EXCEPTION_MESSAGE_LENGTH + 1];
          } ntyExceptionFrame;
          enum {
              ExceptionEntered = 0,//0
              ExceptionThrown,    //1
              ExceptionHandled, //2
              ExceptionFinalized//3
          };
          #define ntyExceptionPopStack    \
              ntyThreadLocalDataSet(ExceptionStack, ((ntyExceptionFrame*)ntyThreadLocalDataGet(ExceptionStack))->next)
          #define ReThrow                    ntyExceptionThrow(frame.exception, frame.func, frame.file, frame.line, NULL)
          #define Throw(e, cause, ...)    ntyExceptionThrow(&(e), __func__, __FILE__, __LINE__, cause, ##__VA_ARGS__,NULL)
          #define Try do {                                                                        \
                      volatile int Exception_flag;                                                \
                      ntyExceptionFrame frame;                                                    \
                      frame.message[0] = 0;                                                       \
                      frame.next = (ntyExceptionFrame*)ntyThreadLocalDataGet(ExceptionStack);     \
                      ntyThreadLocalDataSet(ExceptionStack, &frame);                              \
                      Exception_flag = setjmp(frame.env);                                         \
                      if (Exception_flag == ExceptionEntered) {
          #define Catch(nty_exception) \
                          if (Exception_flag == ExceptionEntered) ntyExceptionPopStack; \
                      } else if (frame.exception == &(nty_exception)) { \
                          Exception_flag = ExceptionHandled;
          #define Finally \
                          if (Exception_flag == ExceptionEntered) ntyExceptionPopStack; \
                      } { \
                          if (Exception_flag == ExceptionEntered)    \
                              Exception_flag = ExceptionFinalized;
          #define EndTry \
                          if (Exception_flag == ExceptionEntered) ntyExceptionPopStack; \
                      } if (Exception_flag == ExceptionThrown) {ReThrow;} \
                      } while (0)
          void ntyExceptionThrow(ntyException *excep, const char *func, const char *file, int line, const char *cause, ...) {
              va_list ap;
              ntyExceptionFrame *frame = (ntyExceptionFrame *) ntyThreadLocalDataGet(ExceptionStack);
              if (frame) {
                  //异常名
                  frame->exception = excep;
                  frame->func = func;
                  frame->file = file;
                  frame->line = line;
                  //异常打印的信息
                  if (cause) {
                      va_start(ap, cause);
                      vsnprintf(frame->message, EXCEPTION_MESSAGE_LENGTH, cause, ap);
                      va_end(ap);
                  }
                  ntyExceptionPopStack;
                  longjmp(frame->env, ExceptionThrown);
              }
                  //没有被catch,直接throw
              else if (cause) {
                  char message[EXCEPTION_MESSAGE_LENGTH + 1];
                  va_start(ap, cause);
                  vsnprintf(message, EXCEPTION_MESSAGE_LENGTH, cause, ap);
                  va_end(ap);
                  printf("%s: %s\n raised in %s at %s:%d\n", excep->name, message, func ? func : "?", file ? file : "?", line);
              }
              else {
                  printf("%s: %p\n raised in %s at %s:%d\n", excep->name, excep, func ? func : "?", file ? file : "?", line);
              }
          }
          

          Debug测试代码

          /* ** **** ******** **************** debug **************** ******** **** ** */
          ntyException A = {"AException"};
          ntyException B = {"BException"};
          ntyException C = {"CException"};
          ntyException D = {"DException"};
          void *thread(void *args) {
              pthread_t selfid = pthread_self();
              Try
                      {
                          Throw(A, "A");
                      }
                  Catch (A)
                      {
                          printf("catch A : %ld\n", selfid);
                      }
              EndTry;
              Try
                      {
                          Throw(B, "B");
                      }
                  Catch (B)
                      {
                          printf("catch B : %ld\n", selfid);
                      }
              EndTry;
              Try
                      {
                          Throw(C, "C");
                      }
                  Catch (C)
                      {
                          printf("catch C : %ld\n", selfid);
                      }
              EndTry;
              Try
                      {
                          Throw(D, "D");
                      }
                  Catch (D)
                      {
                          printf("catch D : %ld\n", selfid);
                      }
              EndTry;
              Try
                      {
                          Throw(A, "A Again");
                          Throw(B, "B Again");
                          Throw(C, "C Again");
                          Throw(D, "D Again");
                      }
                  Catch (A)
                      {
                          printf("catch A again : %ld\n", selfid);
                      }
                  Catch (B)
                      {
                          printf("catch B again : %ld\n", selfid);
                      }
                  Catch (C)
                      {
                          printf("catch C again : %ld\n", selfid);
                      }
                  Catch (D)
                      {
                          printf("catch B again : %ld\n", selfid);
                      }
              EndTry;
          }
          #define PTHREAD_NUM        8
          int main(void) {
              ntyExceptionInit();
              printf("\n\n=> Test1: Throw\n");
              {
                  Throw(D, NULL);     //ntyExceptionThrow(&(D), "_function_name_", "_file_name_", 202, ((void *) 0), ((void *) 0))
                  Throw(C, "null C"); //ntyExceptionThrow(&(C), "_function_name_", "_file_name_", 203, "null C", ((void *) 0))
              }
              printf("=> Test1: Ok\n\n");
              printf("\n\n=> Test2: Try-Catch Double Nesting\n");
              {
                  Try
                          {
                              Try
                                      {
                                          Throw(B, "call B");
                                      }
                                  Catch (B)
                                      {
                                          printf("catch B \n");
                                      }
                              EndTry;
                              Throw(A, NULL);
                          }
                      Catch(A)
                          {
                              printf("catch A \n");
                              printf("Result: Ok\n");
                          }
                  EndTry;
              }
              printf("=> Test2: Ok\n\n");
              printf("\n\n=> Test3: Try-Catch Triple  Nesting\n");
              {
                  Try
                          {
                              Try
                                      {
                                          Try
                                                  {
                                                      Throw(C, "call C");
                                                  }
                                              Catch (C)
                                                  {
                                                      printf("catch C\n");
                                                  }
                                          EndTry;
                                          Throw(B, "call B");
                                      }
                                  Catch (B)
                                      {
                                          printf("catch B\n");
                                      }
                              EndTry;
                              Throw(A, NULL);
                          }
                      Catch(A)
                          {
                              printf("catch A\n");
                          }
                  EndTry;
              }
              printf("=> Test3: Ok\n\n");
              printf("=> Test4: Test Thread-safeness\n");
              int i = 0;
              pthread_t th_id[PTHREAD_NUM];
              for (i = 0; i < PTHREAD_NUM; i++) {
                  pthread_create(&th_id[i], NULL, thread, NULL);
              }
              for (i = 0; i < PTHREAD_NUM; i++) {
                  pthread_join(th_id[i], NULL);
              }
              printf("=> Test4: Ok\n\n");
              printf("\n\n=> Test5: No Success Catch\n");
              {
                  Try
                          {
                              Throw(A, "no catch A ,should Rethrow");
                          }
                  EndTry;
              }
              printf("=> Test5: Rethrow Success\n\n");
              printf("\n\n=> Test6: Normal Test\n");
              {
                  Try
                          {
                              Throw(A, "call A");
                          }
                      Catch(A)
                          {
                              printf("catch A\n");
                          }
                      Finally
                          {
                              printf("wxf nb\n");
                          };
                  EndTry;
              }
              printf("=> Test6: ok\n\n");
          }
          

          线程安全、try-catch、Debug测试代码>
          #include <stdio.h>
          #include <setjmp.h>
          #include <pthread.h>
          #include <stdarg.h>
          /* ** **** ******** **************** Thread safety **************** ******** **** ** */
          #define ntyThreadLocalData                      pthread_key_t
          #define ntyThreadLocalDataSet(key, value)       pthread_setspecific((key), (value))
          #define ntyThreadLocalDataGet(key)              pthread_getspecific((key))
          #define ntyThreadLocalDataCreate(key)           pthread_key_create(&(key), NULL)
          ntyThreadLocalData ExceptionStack;
          static void init_once(void) {
              ntyThreadLocalDataCreate(ExceptionStack);
          }
          static pthread_once_t once_control = PTHREAD_ONCE_INIT;
          void ntyExceptionInit(void) {
              pthread_once(&once_control, init_once);
          }
          /* ** **** ******** **************** try / catch / finally / throw **************** ******** **** ** */
          #define EXCEPTION_MESSAGE_LENGTH                512
          typedef struct _ntyException {
              const char *name;
          } ntyException;
          ntyException SQLException = {"SQLException"};
          ntyException TimeoutException = {"TimeoutException"};
          typedef struct _ntyExceptionFrame {
              jmp_buf env;
              int line;
              const char *func;
              const char *file;
              ntyException *exception;
              struct _ntyExceptionFrame *next;
              char message[EXCEPTION_MESSAGE_LENGTH + 1];
          } ntyExceptionFrame;
          enum {
              ExceptionEntered = 0,//0
              ExceptionThrown,    //1
              ExceptionHandled, //2
              ExceptionFinalized//3
          };
          #define ntyExceptionPopStack    \
              ntyThreadLocalDataSet(ExceptionStack, ((ntyExceptionFrame*)ntyThreadLocalDataGet(ExceptionStack))->next)
          #define ReThrow                    ntyExceptionThrow(frame.exception, frame.func, frame.file, frame.line, NULL)
          #define Throw(e, cause, ...)    ntyExceptionThrow(&(e), __func__, __FILE__, __LINE__, cause, ##__VA_ARGS__,NULL)
          #define Try do {                                                                        \
                      volatile int Exception_flag;                                                \
                      ntyExceptionFrame frame;                                                    \
                      frame.message[0] = 0;                                                       \
                      frame.next = (ntyExceptionFrame*)ntyThreadLocalDataGet(ExceptionStack);     \
                      ntyThreadLocalDataSet(ExceptionStack, &frame);                              \
                      Exception_flag = setjmp(frame.env);                                         \
                      if (Exception_flag == ExceptionEntered) {
          #define Catch(nty_exception) \
                          if (Exception_flag == ExceptionEntered) ntyExceptionPopStack; \
                      } else if (frame.exception == &(nty_exception)) { \
                          Exception_flag = ExceptionHandled;
          #define Finally \
                          if (Exception_flag == ExceptionEntered) ntyExceptionPopStack; \
                      } { \
                          if (Exception_flag == ExceptionEntered)    \
                              Exception_flag = ExceptionFinalized;
          #define EndTry \
                          if (Exception_flag == ExceptionEntered) ntyExceptionPopStack; \
                      } if (Exception_flag == ExceptionThrown) {ReThrow;} \
                      } while (0)
          void ntyExceptionThrow(ntyException *excep, const char *func, const char *file, int line, const char *cause, ...) {
              va_list ap;
              ntyExceptionFrame *frame = (ntyExceptionFrame *) ntyThreadLocalDataGet(ExceptionStack);
              if (frame) {
                  //异常名
                  frame->exception = excep;
                  frame->func = func;
                  frame->file = file;
                  frame->line = line;
                  //异常打印的信息
                  if (cause) {
                      va_start(ap, cause);
                      vsnprintf(frame->message, EXCEPTION_MESSAGE_LENGTH, cause, ap);
                      va_end(ap);
                  }
                  ntyExceptionPopStack;
                  longjmp(frame->env, ExceptionThrown);
              }
                  //没有被catch,直接throw
              else if (cause) {
                  char message[EXCEPTION_MESSAGE_LENGTH + 1];
                  va_start(ap, cause);
                  vsnprintf(message, EXCEPTION_MESSAGE_LENGTH, cause, ap);
                  va_end(ap);
                  printf("%s: %s\n raised in %s at %s:%d\n", excep->name, message, func ? func : "?", file ? file : "?", line);
              }
              else {
                  printf("%s: %p\n raised in %s at %s:%d\n", excep->name, excep, func ? func : "?", file ? file : "?", line);
              }
          }
          /* ** **** ******** **************** debug **************** ******** **** ** */
          ntyException A = {"AException"};
          ntyException B = {"BException"};
          ntyException C = {"CException"};
          ntyException D = {"DException"};
          void *thread(void *args) {
              pthread_t selfid = pthread_self();
              Try
                      {
                          Throw(A, "A");
                      }
                  Catch (A)
                      {
                          printf("catch A : %ld\n", selfid);
                      }
              EndTry;
              Try
                      {
                          Throw(B, "B");
                      }
                  Catch (B)
                      {
                          printf("catch B : %ld\n", selfid);
                      }
              EndTry;
              Try
                      {
                          Throw(C, "C");
                      }
                  Catch (C)
                      {
                          printf("catch C : %ld\n", selfid);
                      }
              EndTry;
              Try
                      {
                          Throw(D, "D");
                      }
                  Catch (D)
                      {
                          printf("catch D : %ld\n", selfid);
                      }
              EndTry;
              Try
                      {
                          Throw(A, "A Again");
                          Throw(B, "B Again");
                          Throw(C, "C Again");
                          Throw(D, "D Again");
                      }
                  Catch (A)
                      {
                          printf("catch A again : %ld\n", selfid);
                      }
                  Catch (B)
                      {
                          printf("catch B again : %ld\n", selfid);
                      }
                  Catch (C)
                      {
                          printf("catch C again : %ld\n", selfid);
                      }
                  Catch (D)
                      {
                          printf("catch B again : %ld\n", selfid);
                      }
              EndTry;
          }
          #define PTHREAD_NUM        8
          int main(void) {
              ntyExceptionInit();
              printf("\n\n=> Test1: Throw\n");
              {
                  Throw(D, NULL);     //ntyExceptionThrow(&(D), "_function_name_", "_file_name_", 202, ((void *) 0), ((void *) 0))
                  Throw(C, "null C"); //ntyExceptionThrow(&(C), "_function_name_", "_file_name_", 203, "null C", ((void *) 0))
              }
              printf("=> Test1: Ok\n\n");
              printf("\n\n=> Test2: Try-Catch Double Nesting\n");
              {
                  Try
                          {
                              Try
                                      {
                                          Throw(B, "call B");
                                      }
                                  Catch (B)
                                      {
                                          printf("catch B \n");
                                      }
                              EndTry;
                              Throw(A, NULL);
                          }
                      Catch(A)
                          {
                              printf("catch A \n");
                              printf("Result: Ok\n");
                          }
                  EndTry;
              }
              printf("=> Test2: Ok\n\n");
              printf("\n\n=> Test3: Try-Catch Triple  Nesting\n");
              {
                  Try
                          {
                              Try
                                      {
                                          Try
                                                  {
                                                      Throw(C, "call C");
                                                  }
                                              Catch (C)
                                                  {
                                                      printf("catch C\n");
                                                  }
                                          EndTry;
                                          Throw(B, "call B");
                                      }
                                  Catch (B)
                                      {
                                          printf("catch B\n");
                                      }
                              EndTry;
                              Throw(A, NULL);
                          }
                      Catch(A)
                          {
                              printf("catch A\n");
                          }
                  EndTry;
              }
              printf("=> Test3: Ok\n\n");
              printf("=> Test4: Test Thread-safeness\n");
              int i = 0;
              pthread_t th_id[PTHREAD_NUM];
              for (i = 0; i < PTHREAD_NUM; i++) {
                  pthread_create(&th_id[i], NULL, thread, NULL);
              }
              for (i = 0; i < PTHREAD_NUM; i++) {
                  pthread_join(th_id[i], NULL);
              }
              printf("=> Test4: Ok\n\n");
              printf("\n\n=> Test5: No Success Catch\n");
              {
                  Try
                          {
                              Throw(A, "no catch A ,should Rethrow");
                          }
                  EndTry;
              }
              printf("=> Test5: Rethrow Success\n\n");
              printf("\n\n=> Test6: Normal Test\n");
              {
                  Try
                          {
                              Throw(A, "call A");
                          }
                      Catch(A)
                          {
                              printf("catch A\n");
                          }
                      Finally
                          {
                              printf("wxf nb\n");
                          };
                  EndTry;
              }
              printf("=> Test6: ok\n\n");
          }
          void all() {
              ///////////try
              do {
                  volatile int Exception_flag;
                  ntyExceptionFrame frame;
                  frame.message[0] = 0;
                  frame.next = (ntyExceptionFrame *) pthread_getspecific((ExceptionStack));
                  pthread_setspecific((ExceptionStack), (&frame));
                  Exception_flag = _setjmp(frame.env);
                  if (Exception_flag == ExceptionEntered) {
                      ///////////
                      {
                          ///////////try
                          do {
                              volatile int Exception_flag;
                              ntyExceptionFrame frame;
                              frame.message[0] = 0;
                              frame.next = (ntyExceptionFrame *) pthread_getspecific((ExceptionStack));
                              pthread_setspecific((ExceptionStack), (&frame));
                              Exception_flag = _setjmp(frame.env);
                              if (Exception_flag == ExceptionEntered) {
                                  ///////////
                                  {
                                      ///////////Throw(B, "recall B"); --->longjmp ExceptionThrown
                                      ntyExceptionThrow(&(B), "_function_name_", "_file_name_", 302, "recall B", ((void *) 0));
                                      ///////////
                                  }
                                  ///////////Catch (B)
                                  if (Exception_flag == ExceptionEntered)
                                      ntyExceptionPopStack;
                              }
                              else if (frame.exception == &(B)) {
                                  Exception_flag = ExceptionHandled;
                                  ///////////
                                  {    ///////////
                                      printf("recall B \n");
                                      ///////////
                                  }
                                  ////////fin
                                  if (Exception_flag == ExceptionEntered)
                                      ntyExceptionPopStack;
                                  if (Exception_flag == ExceptionEntered)
                                      Exception_flag = ExceptionFinalized;
                                  /////////////////{
                                  {
                                      printf("fin\n");
                                  };
                                  ////////////////////}
                                  ///////////EndTry;
                                  if (Exception_flag == ExceptionEntered)
                                      ntyExceptionPopStack;
                              }
                              if (Exception_flag == ExceptionThrown)
                                  ntyExceptionThrow(frame.exception, frame.func, frame.file, frame.line, ((void *) 0));
                          } while (0);
                          ///////////Throw(A, NULL); longjmp ExceptionThrown
                          ntyExceptionThrow(&(A), "_function_name_", "_file_name_", 329, ((void *) 0), ((void *) 0));
                          ///////////
                      }
                      ///////////Catch(A)
                      if (Exception_flag == ExceptionEntered)
                          ntyExceptionPopStack;
                  }
                  else if (frame.exception == &(A)) {
                      Exception_flag = ExceptionHandled;
                      ///////////
                      {
                          ///////////
                          printf("\tResult: Ok\n");
                          ///////////
                      }
                      /////////// EndTry;
                      if (Exception_flag == ExceptionEntered)
                          ntyExceptionPopStack;
                  }
                  if (Exception_flag == ExceptionThrown)
                      ntyExceptionThrow(frame.exception, frame.func, frame.file, frame.line, ((void *) 0));
              } while (0);
              ///////////
          }

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