[求助]这段程序内存哪儿出问题了哈__getprotobyname_from_CHttpSocket_ppe_m_bConnected_

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[求助]这段程序内存哪儿出问题了哈

来源: 互联网发布时间：2016-02-01

本文导语: 错误在HttpSocket.cpp中的Socket函数中,ppe=gethostbyname("tcp"),就是内存错误，但是我不晓得为什么错了.... bool CHttpSocket::Socket() { if(m_bConnected) return false; struct protoent *ppe=NULL; ppe=getprotobyname("tcp"); m_s=socket(PF_INET,SOCK_STREAM,ppe...

错误在HttpSocket.cpp中的Socket函数中,ppe=gethostbyname("tcp"),就是内存错误，但是我不晓得为什么错了....

bool CHttpSocket::Socket()
{
if(m_bConnected) return false;

struct protoent *ppe=NULL;
ppe=getprotobyname("tcp");

m_s=socket(PF_INET,SOCK_STREAM,ppe->p_proto);
if(m_s==-1)
{
printf("socket() failed!n");
return false;
}

return true;
}

gdb调试的提示是这样的:
****************************************************
CHttpSocket::Socket (this=0xbff9a660) at HttpSocket.cpp:31
31 if(m_bConnected) return false;
(gdb) n
33 struct protoent *ppe=NULL;
(gdb) n
34 ppe=getprotobyname("tcp");
(gdb) n
*** glibc detected *** free(): invalid next size (normal): 0x09e20cd8 ***

Program received signal SIGABRT, Aborted.
0x001327a2 in _dl_sysinfo_int80 () from /lib/ld-linux.so.2
(gdb) bt
#0 0x001327a2 in _dl_sysinfo_int80 () from /lib/ld-linux.so.2
#1 0x001727f5 in raise () from /lib/tls/libc.so.6
#2 0x00174199 in abort () from /lib/tls/libc.so.6
#3 0x001a64ea in __libc_message () from /lib/tls/libc.so.6
#4 0x001acc6f in _int_free () from /lib/tls/libc.so.6
#5 0x001acfea in free () from /lib/tls/libc.so.6
#6 0x0019d516 in fclose@@GLIBC_2.1 () from /lib/tls/libc.so.6
#7 0x00825305 in _nss_files_getprotobyname_r () from /lib/libnss_files.so.2
#8 0x00229332 in getprotobyname_r@@GLIBC_2.1.2 () from /lib/tls/libc.so.6
#9 0x002291f1 in getprotobyname () from /lib/tls/libc.so.6
#10 0x0804961e in CHttpSocket::Socket (this=0xbff9a660) at HttpSocket.cpp:34
#11 0x08048ed4 in Run (strUrl=0xbffcdb25 "http://hi.baidu.com") at http.cpp:54
#12 0x08048d60 in main (args=2, argv=0xbff9b074) at http.cpp:16

代码在这儿 http.rar

pp类型错误.应该为
struct hostent

ppe

If no error occurs, getprotobyname returns a pointer to the protoent. Otherwise, it returns a null pointer
so,the program will be dump at m_s=socket(PF_INET,SOCK_STREAM,ppe->p_proto);

ppe=getprotobyname("tcp");
没有检查ppe的值

这段代码是没有问题的，一定是其它的部分引起的问题，下面的程序是可以运行的。
#include
#include
#include

#include

#include
using namespace std;

class CHttpSocket
{
public:
        bool Socket();
        CHttpSocket()
        {
               m_bConnected = false;
               m_s = 0;
        }
private:
        bool m_bConnected;
        int m_s;
};

bool CHttpSocket::Socket()
{
        if(m_bConnected) return false;

        struct protoent *ppe=NULL;
        ppe=getprotobyname("tcp");
        cout