vs2013 调试libevent 源码

自己内功的提升，无非是向前辈学习和修炼自身，对于编码也是如此，学习优秀的库只有从

源代码学起，才能深刻理解库实现的来龙去脉，加深自己的理解，提升自己的功力。

今天就介绍一下vs2013 下面调试libevent源码。不需要创建sln解决方案，只需要创建工程，包含

源码目录即可源码调试。

1、手工添加print-winsocke-errors.c文件，不然nmake编译的时候会报错。

print-winsocke-errors.c源代码程序：

 #include <winsock2.h>
 #include <windows.h>

 #include <stdlib.h>
 #include <stdio.h>

 #include "event2/event.h"
 #include "event2/util.h"
 #include "event2/thread.h"

 #define E(x) printf (#x " -> \"%s\"\n", evutil_socket_error_to_string (x));

 int main (int argc, char **argv)
 {
   int i, j;
   const char *s1, *s2;

 #ifdef EVTHREAD_USE_WINDOWS_THREADS_IMPLEMENTED
   evthread_use_windows_threads ();
 #endif

   s1 = evutil_socket_error_to_string (WSAEINTR);

   for (i = ; i < ; i++) {
     printf ("\niteration %d:\n\n", i);
     E(WSAEINTR);
     E(WSAEACCES);
     E(WSAEFAULT);
     E(WSAEINVAL);
     E(WSAEMFILE);
     E(WSAEWOULDBLOCK);
     E(WSAEINPROGRESS);
     E(WSAEALREADY);
     E(WSAENOTSOCK);
     E(WSAEDESTADDRREQ);
     E(WSAEMSGSIZE);
     E(WSAEPROTOTYPE);
     E(WSAENOPROTOOPT);
     E(WSAEPROTONOSUPPORT);
     E(WSAESOCKTNOSUPPORT);
     E(WSAEOPNOTSUPP);
     E(WSAEPFNOSUPPORT);
     E(WSAEAFNOSUPPORT);
     E(WSAEADDRINUSE);
     E(WSAEADDRNOTAVAIL);
     E(WSAENETDOWN);
     E(WSAENETUNREACH);
     E(WSAENETRESET);
     E(WSAECONNABORTED);
     E(WSAECONNRESET);
     E(WSAENOBUFS);
     E(WSAEISCONN);
     E(WSAENOTCONN);
     E(WSAESHUTDOWN);
     E(WSAETIMEDOUT);
     E(WSAECONNREFUSED);
     E(WSAEHOSTDOWN);
     E(WSAEHOSTUNREACH);
     E(WSAEPROCLIM);
     E(WSASYSNOTREADY);
     E(WSAVERNOTSUPPORTED);
     E(WSANOTINITIALISED);
     E(WSAEDISCON);
     E(WSATYPE_NOT_FOUND);
     E(WSAHOST_NOT_FOUND);
     E(WSATRY_AGAIN);
     E(WSANO_RECOVERY);
     E(WSANO_DATA);
     E(0xdeadbeef); /* test the case where no message is available */

     /* fill up the hash table a bit to make sure it grows properly */
     for (j = ; j < ; j++) {
       int err;
       evutil_secure_rng_get_bytes(&err, sizeof(err));
       evutil_socket_error_to_string(err);
     }
   }

   s2 = evutil_socket_error_to_string (WSAEINTR);
   if (s1 != s2)
     printf ("caching failed!\n");

   libevent_global_shutdown ();

   return EXIT_SUCCESS;
 }

2、修改Makefile.nmake 

将

CFLAGS=$(CFLAGS) /Ox /W3 /wd4996 /nologo

改为

CFLAGS=$(CFLAGS) /Od /W3 /wd4996 /nologo /Zi

使用/Od禁止优化，使用/Zi 生成调试信息。

3、vs2013命令行编译：nmake /f Makefile.nmake

编译生成：

4、新建工程，附加源码调试

解决方案包含源代码目录：

　　以上三个目录添加到VC的附加库目录。

　   lib包含目录添加刚才生成的

　　所在目录

5、源码跟踪调试

F11跳入源码调试：

附上测试代码：

 // libevent-test.cpp : 定义控制台应用程序的入口点。
 //

 #include "stdafx.h"

 #pragma comment(lib,"ws2_32.lib")
 #pragma comment(lib,"wsock32.lib")
 #pragma comment(lib,"libevent.lib")
 #pragma comment(lib,"libevent_core.lib")
 #pragma comment(lib,"libevent_extras.lib")

 #include <sys/types.h>

 #include <event2/event-config.h>

 #include <sys/stat.h>
 #ifndef _WIN32
 #include <sys/queue.h>
 #include <unistd.h>
 #endif
 #include <time.h>
 #ifdef EVENT__HAVE_SYS_TIME_H
 #include <sys/time.h>
 #endif
 #include <fcntl.h>
 #include <stdlib.h>
 #include <stdio.h>
 #include <string.h>
 #include <errno.h>

 #include <event2/event.h>
 #include <event2/event_struct.h>
 #include <event2/util.h>

 #ifdef _WIN32
 #include <winsock2.h>
 #endif

 struct timeval lasttime;

 int event_is_persistent;

 static void
 timeout_cb(evutil_socket_t fd, short event, void *arg)
 {
     struct timeval newtime, difference;
     struct event *timeout = (struct event *)arg;
     double elapsed;

     evutil_gettimeofday(&newtime, NULL);
     evutil_timersub(&newtime, &lasttime, &difference);
     elapsed = difference.tv_sec +
         (difference.tv_usec / 1.0e6);

     printf("timeout_cb called at %d: %.3f seconds elapsed.\n",
         (int)newtime.tv_sec, elapsed);
     lasttime = newtime;

     if (!event_is_persistent) {
         struct timeval tv;
         evutil_timerclear(&tv);
         tv.tv_sec = ;
         event_add(timeout, &tv);
     }
 }

 int
 main(int argc, char **argv)
 {
     struct event timeout;
     struct timeval tv;
     struct event_base *base;
     int flags;

 #ifdef _WIN32
     WORD wVersionRequested;
     WSADATA wsaData;

     wVersionRequested = MAKEWORD(, );

     (void)WSAStartup(wVersionRequested, &wsaData);
 #endif

     if (argc ==  && !strcmp(argv[], "-p")) {
         event_is_persistent = ;
         flags = EV_PERSIST;
     }
     else {
         event_is_persistent = ;
         flags = ;
     }

     /* Initalize the event library */
     base = event_base_new();

     /* Initalize one event */
     event_assign(&timeout, base, -, flags, timeout_cb, (void*)&timeout);

     evutil_timerclear(&tv);
     tv.tv_sec = ;
     event_add(&timeout, &tv);

     evutil_gettimeofday(&lasttime, NULL);

     event_base_dispatch(base);

     return ();
 }

　　以上就是vs2013下的源码跟踪调试，下面就开始对libevent深入学习了。

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