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 Demo4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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