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"
", 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 = 0; i < 3; i++) {
    printf ("
iteration %d:

", 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 = 0; j < 50; 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!
");

  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.
",
        (int)newtime.tv_sec, elapsed);
    lasttime = newtime;

    if (!event_is_persistent) {
        struct timeval tv;
        evutil_timerclear(&tv);
        tv.tv_sec = 2;
        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(2, 2);

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

    if (argc == 2 && !strcmp(argv[1], "-p")) {
        event_is_persistent = 1;
        flags = EV_PERSIST;
    }
    else {
        event_is_persistent = 0;
        flags = 0;
    }

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

    /* Initalize one event */
    event_assign(&timeout, base, -1, flags, timeout_cb, (void*)&timeout);

    evutil_timerclear(&tv);
    tv.tv_sec = 2;
    event_add(&timeout, &tv);

    evutil_gettimeofday(&lasttime, NULL);

    event_base_dispatch(base);

    return (0);
}

　　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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