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
- try
- throw
- Catch
- Finally
- EndTry
- try-catch代码
- Debug测试代码
- 线程安全、try-catch、Debug测试代码 汇总
try / catch / finally / throw 介绍
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, idx):跳转到设置env的位置,第二个参数就是setjmp()的返回值
#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 和 setjmp/longjmp 的关系
try ---> setjmp(env) throw ---> 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 Demo
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. 在哪个文件哪个函数哪个行抛的异常
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. try-catch嵌套怎么做?
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. try-catch线程安全
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(&(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 汇总
#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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