epoll的奇怪問題---【已解決】

banceleung

先貼代碼后解釋 #include <pthread.h>

1. 
   
2. #include <sys/epoll.h>
   
3. 
   
4. class CNetMsgImp
   
5. 
   
6. {
   
7. 
   
8. public:        
   
9. 
   
10.         struct epoll_event m_events[12];
    
11. 
    
12.         //char temp[1000]; //-------!!!!!!!!!!!!----------        
    
13. 
    
14.         int m_kdpfd;
    
15. 
    
16.         CNetMsgImp();
    
17. 
    
18.         ~CNetMsgImp();
    
19. 
    
20. };
    
21. 
    
22. CNetMsgImp::CNetMsgImp()
    
23. 
    
24. {               
    
25. 
    
26.         m_kdpfd = epoll_create(11+11);  
    
27. 
    
28.   m_events[11].events = 11;
    
29. 
    
30.   epoll_wait(m_kdpfd,m_events, 20, -1);   
    
31. 
    
32. }
    
33. 
    
34. int main(int argc, char* argv[])
    
35. 
    
36. {               
    
37. 
    
38.         CNetMsgImp* netMsgImg = new CNetMsgImp;        
    
39. 
    
40. }
    

復(fù)制代碼

g++ -pthread -o test test.cpp
valgrind --tool=memcheck ./test


==11054== Memcheck, a memory error detector.
==11054== Copyright (C) 2002-2007, and GNU GPL'd, by Julian Seward et al.
==11054== Using LibVEX rev 1804, a library for dynamic binary translation.
==11054== Copyright (C) 2004-2007, and GNU GPL'd, by OpenWorks LLP.
==11054== Using valgrind-3.3.0-Debian, a dynamic binary instrumentation framework.
==11054== Copyright (C) 2000-2007, and GNU GPL'd, by Julian Seward et al.
==11054== For more details, rerun with: -v
==11054==
==11054== Syscall param epoll_wait(events) points to unaddressable byte(s)
==11054==    at 0x40007F2: (within /lib/ld-2.7.so)
==11054==    by 0x8048623: main (in /mnt/hgfs/NetFrameL/test)
==11054==  Address 0x42c10bc is 0 bytes after a block of size 148 alloc'd
==11054==    at 0x4023294: operator new(unsigned) (vg_replace_malloc.c:224)
==11054==    by 0x8048615: main (in /mnt/hgfs/NetFrameL/test) #include <pthread.h>

1. 
   
2. #include <sys/epoll.h>
   
3. 
   
4. class CNetMsgImp
   
5. 
   
6. {
   
7. 
   
8. public:        
   
9. 
   
10.         struct epoll_event m_events[12];        
    
11. 
    
12.         char temp[1000];
    
13. 
    
14.         int m_kdpfd;
    
15. 
    
16.         CNetMsgImp();
    
17. 
    
18.         ~CNetMsgImp();
    
19. 
    
20. };
    
21. 
    
22. CNetMsgImp::CNetMsgImp()
    
23. 
    
24. {               
    
25. 
    
26.         m_kdpfd = epoll_create(11+11);  
    
27. 
    
28.   m_events[11].events = 11;
    
29. 
    
30.   epoll_wait(m_kdpfd,m_events, 20, -1);   
    
31. 
    
32. }
    
33. 
    
34. int main(int argc, char* argv[])
    
35. 
    
36. {        
    
37. 
    
38.         CNetMsgImp* netMsgImg = new CNetMsgImp;        
    
39. 
    
40. }
    

復(fù)制代碼

g++ -pthread -o test test.cpp
valgrind --tool=memcheck ./test


==11092== Memcheck, a memory error detector.
==11092== Copyright (C) 2002-2007, and GNU GPL'd, by Julian Seward et al.
==11092== Using LibVEX rev 1804, a library for dynamic binary translation.
==11092== Copyright (C) 2004-2007, and GNU GPL'd, by OpenWorks LLP.
==11092== Using valgrind-3.3.0-Debian, a dynamic binary instrumentation framework.
==11092== Copyright (C) 2000-2007, and GNU GPL'd, by Julian Seward et al.
==11092== For more details, rerun with: -v
==11092==

如上，如果在類里不加那個(gè)char temp[1000];則valgrind會(huì)報(bào)錯(cuò)，運(yùn)行時(shí)程序會(huì)有棧錯(cuò)誤，明確的說會(huì)侵占對(duì)象內(nèi)存，改變現(xiàn)有對(duì)象的內(nèi)部數(shù)據(jù)。
以上代碼是原有程序的簡化，已能說明問題。

1. 
   
2. #include <sys/epoll.h>
   
3. 
   
4. class A
   
5. 
   
6. {
   
7. 
   
8.         public:
   
9. 
   
10.         int a;
    
11. 
    
12.         struct epoll_event m_events[12];
    
13. 
    
14.         //char temp[1000];
    
15. 
    
16.         A();
    
17. 
    
18.         ~A();
    
19. 
    
20. };
    
21. 
    
22. A::A()
    
23. 
    
24. {
    
25. 
    
26.         a = epoll_create(11+11);  
    
27. 
    
28.         epoll_wait(a,m_events, 20, -1);   
    
29. 
    
30. }
    
31. 
    
32. int main(void)
    
33. 
    
34. {
    
35. 
    
36.         A* b = new A;
    
37. 
    
38. }
    

復(fù)制代碼

來個(gè)更簡單的，問題照舊。

hellioncu

struct epoll_event m_events[12];

epoll_wait(a,m_events, 20, -1);

上面是12，下面是20

peidright

{:3_191:}，奇怪，我這里運(yùn)行沒有問題。。。
ubuntu 64bit gcc 4.33

banceleung

回復(fù) 2# hellioncu


       大意了大意了，多謝��！

rain_fish

epoll_wait(a,m_events, 12, -1);

rain_fish

[root@localhost test]# valgrind --tool=memcheck ./epoll
==18449== Memcheck, a memory error detector
==18449== Copyright (C) 2002-2009, and GNU GPL'd, by Julian Seward et al.
==18449== Using Valgrind-3.5.0 and LibVEX; rerun with -h for copyright info
==18449== Command: ./epoll
==18449==
==18449==
==18449== HEAP SUMMARY:
==18449==     in use at exit: 148 bytes in 1 blocks
==18449==   total heap usage: 1 allocs, 0 frees, 148 bytes allocated
==18449==
==18449== LEAK SUMMARY:
==18449==    definitely lost: 0 bytes in 0 blocks
==18449==    indirectly lost: 0 bytes in 0 blocks
==18449==      possibly lost: 0 bytes in 0 blocks
==18449==    still reachable: 148 bytes in 1 blocks
==18449==         suppressed: 0 bytes in 0 blocks
==18449== Rerun with --leak-check=full to see details of leaked memory
==18449==
==18449== For counts of detected and suppressed errors, rerun with: -v
==18449== ERROR SUMMARY: 0 errors from 0 contexts (suppressed: 15 from

peidright

”hgfs/NetFrameL“
...呵呵！。 準(zhǔn)備開源么。。

banceleung

回復(fù) 7# peidright


    老板沒意見的話我也倒是樂意。

   vmware--tool的默認(rèn)路徑。

chary8088

LS正確

peidright

回復(fù) 8# banceleung
搜google發(fā)現(xiàn)了。開始以為是 high speed google file system...