webbench介绍

/*
 * (C) Radim Kolar 1997-2004
 * This is free software, see GNU Public License version 2 for
 * details.
 *
 * Simple forking WWW Server benchmark:
 *
 * Usage:
 *   webbench --help
 *
 * Return codes:
 *    0 - sucess
 *    1 - benchmark failed (server is not on-line)
 *    2 - bad param
 *    3 - internal error, fork failed
 * 
 */ 
#include "socket.c"
#include <unistd.h>
#include <sys/param.h>
#include <rpc/types.h>
#include <getopt.h>
#include <strings.h>
#include <time.h>
#include <signal.h>

/* values */
volatile int timerexpired=0;
int speed=0;
int failed=0;
int bytes=0;
/* globals */
int http10=1; /* 0 - http/0.9, 1 - http/1.0, 2 - http/1.1 */
/* Allow: GET, HEAD, OPTIONS, TRACE */
#define METHOD_GET 0
#define METHOD_HEAD 1
#define METHOD_OPTIONS 2
#define METHOD_TRACE 3
#define PROGRAM_VERSION "1.5"
int method=METHOD_GET;
int clients=1;
int force=0;
int force_reload=0;
int proxyport=80;
char *proxyhost=NULL;
int benchtime=30;
/* internal */
int mypipe[2];
char host[MAXHOSTNAMELEN];
#define REQUEST_SIZE 2048
char request[REQUEST_SIZE];

static const struct option long_options[]=
{
 {"force",no_argument,&force,1},
 {"reload",no_argument,&force_reload,1},
 {"time",required_argument,NULL,'t'},
 {"help",no_argument,NULL,'?'},
 {"http09",no_argument,NULL,'9'},
 {"http10",no_argument,NULL,'1'},
 {"http11",no_argument,NULL,'2'},
 {"get",no_argument,&method,METHOD_GET},
 {"head",no_argument,&method,METHOD_HEAD},
 {"options",no_argument,&method,METHOD_OPTIONS},
 {"trace",no_argument,&method,METHOD_TRACE},
 {"version",no_argument,NULL,'V'},
 {"proxy",required_argument,NULL,'p'},
 {"clients",required_argument,NULL,'c'},
 {NULL,0,NULL,0}
};

/* prototypes */
static void benchcore(const char* host,const int port, const char *request);
static int bench(void);
static void build_request(const char *url);

static void alarm_handler(int signal)
{
   timerexpired=1;
}	

static void usage(void)
{
   fprintf(stderr,
	"webbench [option]... URL\n"
	"  -f|--force               Don't wait for reply from server.\n"
	"  -r|--reload              Send reload request - Pragma: no-cache.\n"
	"  -t|--time <sec>          Run benchmark for <sec> seconds. Default 30.\n"
	"  -p|--proxy <server:port> Use proxy server for request.\n"
	"  -c|--clients <n>         Run <n> HTTP clients at once. Default one.\n"
	"  -9|--http09              Use HTTP/0.9 style requests.\n"
	"  -1|--http10              Use HTTP/1.0 protocol.\n"
	"  -2|--http11              Use HTTP/1.1 protocol.\n"
	"  --get                    Use GET request method.\n"
	"  --head                   Use HEAD request method.\n"
	"  --options                Use OPTIONS request method.\n"
	"  --trace                  Use TRACE request method.\n"
	"  -?|-h|--help             This information.\n"
	"  -V|--version             Display program version.\n"
	);
};
int main(int argc, char *argv[])
{
 int opt=0;
 int options_index=0;
 char *tmp=NULL;

 if(argc==1)
 {
	  usage();
          return 2;
 } 

 while((opt=getopt_long(argc,argv,"912Vfrt:p:c:?h",long_options,&options_index))!=EOF )
 {
  switch(opt)
  {
   case  0 : break;
   case 'f': force=1;break;
   case 'r': force_reload=1;break; 
   case '9': http10=0;break;
   case '1': http10=1;break;
   case '2': http10=2;break;
   case 'V': printf(PROGRAM_VERSION"\n");exit(0);
   case 't': benchtime=atoi(optarg);break;	     
   case 'p':          //设置了代理主机和ip地址
	     /* proxy server parsing server:port */
	     tmp=strrchr(optarg,':');     //返回 ":" 的指针
	     proxyhost=optarg;     //表示主机的ip地址
	     if(tmp==NULL)   //表示没有指定端口  使用默认端口   eg： -p www.abc.com
	     {
		     break;
	     }
	     if(tmp==optarg)  //表示没有代理主机名
	     {
		     fprintf(stderr,"Error in option --proxy %s: Missing hostname.\n",optarg);
		     return 2;
	     }
	     if(tmp==optarg+strlen(optarg)-1)   //有 ":" 但是没有端口号   -p www.abc.com:    便会报错
	     {
		     fprintf(stderr,"Error in option --proxy %s Port number is missing.\n",optarg);
		     return 2;
	     }
	     *tmp='\0';   //来设置主机的最后一个字符为null表示结束
	     proxyport=atoi(tmp+1);break;   //去掉主机剩下的便是端口号
       /*
        这里设置代理，从optarg中获取我们指定的代理，如果代理没有端口会使用默认端口，如果有指定的端口则将代理主机和端口分开分别存储到tmp和proxyport中
        eg：-p www.abc.com：200
        会将tmp="www.abc.com"    proxyport=200
       */
   case ':':
   case 'h':
   case '?': usage();return 2;break;
   case 'c': clients=atoi(optarg);break;     //来设置并发数
  }
 }
 
 if(optind==argc) {    //optind最后会指向最后一个非选项   如果这个相等便表示没有url   因为url不是选项
                      fprintf(stderr,"webbench: Missing URL!\n");
		      usage();
		      return 2;
                    }

 if(clients==0) clients=1;      //防止用户设置   -c 0  这样变不会创建进程
 if(benchtime==0) benchtime=60;   //防止用户设置   -t 0  
 /* Copyright */
 fprintf(stderr,"Webbench - Simple Web Benchmark "PROGRAM_VERSION"\n"
	 "Copyright (c) Radim Kolar 1997-2004, GPL Open Source Software.\n"
	 );
 build_request(argv[optind]);     //最后一个参数为url
 /* print bench info */
 printf("\nBenchmarking: ");
 switch(method)    //显示使用的请求方式
 {
	 case METHOD_GET:
	 default:
		 printf("GET");break;
	 case METHOD_OPTIONS:
		 printf("OPTIONS");break;
	 case METHOD_HEAD:
		 printf("HEAD");break;
	 case METHOD_TRACE:
		 printf("TRACE");break;
 }
 printf(" %s",argv[optind]);
 switch(http10)
 {
	 case 0: printf(" (using HTTP/0.9)");break;
	 case 2: printf(" (using HTTP/1.1)");break;
 }
 printf("\n");
 if(clients==1) printf("1 client");
 else
   printf("%d clients",clients);

 printf(", running %d sec", benchtime);
 if(force) printf(", early socket close");
 if(proxyhost!=NULL) printf(", via proxy server %s:%d",proxyhost,proxyport);
 if(force_reload) printf(", forcing reload");
 printf(".\n");
 /*
  这个函数的作用便是设置一些基本选项并将一些信息展示出来
 */
 return bench();
}

/*
下面这个函数的作用便是构造请求并且获取目标主机的主机名和端口号   这里有代理和没代理设置的请求头是不一样的。
*/
void build_request(const char *url)
{
  char tmp[10];
  int i;

  bzero(host,MAXHOSTNAMELEN);
  bzero(request,REQUEST_SIZE);

  if(force_reload && proxyhost!=NULL && http10<1) http10=1;
  if(method==METHOD_HEAD && http10<1) http10=1;
  if(method==METHOD_OPTIONS && http10<2) http10=2;
  if(method==METHOD_TRACE && http10<2) http10=2;

  switch(method)
  {
	  default:
	  case METHOD_GET: strcpy(request,"GET");break;      //开始构造http请求  GET
	  case METHOD_HEAD: strcpy(request,"HEAD");break;
	  case METHOD_OPTIONS: strcpy(request,"OPTIONS");break;
	  case METHOD_TRACE: strcpy(request,"TRACE");break;
  }
		  
  strcat(request," ");     //构造GET请求 

  if(NULL==strstr(url,"://"))     //判断“://”是否为url的字串如果是返回第一次出现的位置，不是返回NULL   
  {
	  fprintf(stderr, "\n%s: is not a valid URL.\n",url);
	  exit(2);
  }
  if(strlen(url)>1500)
  {
         fprintf(stderr,"URL is too long.\n");
	 exit(2);
  }
  if(proxyhost==NULL)
	   if (0!=strncasecmp("http://",url,7))      //判断两个字符串是否相等  忽略大小写
	   { fprintf(stderr,"\nOnly HTTP protocol is directly supported, set --proxy for others.\n");
             exit(2);
           }
  /* protocol/host delimiter */
  i=strstr(url,"://")-url+3;   //主机之前有多少个字符，即http://
  /* printf("%d\n",i); */

  if(strchr(url+i,'/')==NULL) {    //如果url=https://www.baidu.com/  则url+i指向www.baidu.com/    strchr查找/首次出现在url+i中的位置  没有返回NULL
                                fprintf(stderr,"\nInvalid URL syntax - hostname don't ends with '/'.\n");
                                exit(2);
                              }
  /*
    上面对我们输入的url做了很多的检测  判断用户输入的url是否符合标准
    检测了  ：//
    检测了   http：//
    检测了url的长度
    检测了主机名后面是否带目录名  eg:https://www.baidu.com/   符合标准      https://www.baidu.com不符合标准   检测了www.baidu.com/  中的 ‘/’
    从上面的条件看都是代理主机为NULL时才会检测这些的  
  */
  if(proxyhost==NULL)
  {
   /* get port from hostname */
   if(index(url+i,':')!=NULL &&
      index(url+i,':')<index(url+i,'/'))     //当带端口号时  将端口号取出
   {
	   strncpy(host,url+i,strchr(url+i,':')-url-i);      //  url=https://www.baidu.com：80/aa.php    ->host=www.baidu.com
	   bzero(tmp,10);
	   strncpy(tmp,index(url+i,':')+1,strchr(url+i,'/')-index(url+i,':')-1);     //得出端口号
	   /* printf("tmp=%s\n",tmp); */
	   proxyport=atoi(tmp);
	   if(proxyport==0) proxyport=80;    //防止获取的端口号问为 0
   } 
   else
   {
     strncpy(host,url+i,strcspn(url+i,"/"));    // strcspn检测url+i字符串中连续有多少个不含 ‘/’
   }
   /*
    上面这个if-else语句用来获取url中的主机名到host中，如果有端口号也会夺取端口号到proxyport中
   */

   // printf("Host=%s\n",host);
   strcat(request+strlen(request),url+i+strcspn(url+i,"/"));   // 请求头  GET www.baidu.com
  } else
  {
   // printf("ProxyHost=%s\nProxyPort=%d\n",proxyhost,proxyport);
   strcat(request,url);   //当代理主机不为空时直接传递url  表示对代理服务器的请求就是一个网址
  }
  if(http10==1)
	  strcat(request," HTTP/1.0");
  else if (http10==2)
	  strcat(request," HTTP/1.1");
  strcat(request,"\r\n");
  /*
    GET www.baidu.com HTTP/1.0

  */
  if(http10>0)
	  strcat(request,"User-Agent: WebBench "PROGRAM_VERSION"\r\n");
   /*
    GET www.baidu.com HTTP/1.0
    User-Agent: WebBench

  */
  if(proxyhost==NULL && http10>0)
  {
	  strcat(request,"Host: ");
	  strcat(request,host);
	  strcat(request,"\r\n");
  }
 /*
    GET www.baidu.com HTTP/1.0
    User-Agent: WebBench
    Host: www.baidu.com

  */
  if(force_reload && proxyhost!=NULL)
  {
	  strcat(request,"Pragma: no-cache\r\n");
  }
   /*
    GET www.baidu.com HTTP/1.0
    User-Agent: WebBench
    Host: www.baidu.com
    Pragma: no-cache
  */
  if(http10>1)
	  strcat(request,"Connection: close\r\n");
  /* add empty line at end */

   /*
    GET www.baidu.com HTTP/1.0
    User-Agent: WebBench
    Host: www.baidu.com
    Pragma: no-cache
    Connection: close
  */
  if(http10>0) strcat(request,"\r\n"); 
  // printf("Req=%s\n",request);

   /*
    GET www.baidu.com HTTP/1.0
    User-Agent: WebBench
    Host: www.baidu.com
    Pragma: no-cache
    Connection: close

  */

  /*
    上面的这些都是构造一些http请求头  当代理主机不为空时很多都没有设置  为空时设置了很多的选项
  */
}

/* vraci system rc error kod */
static int bench(void)
{
  int i,j,k;	
  pid_t pid=0;
  FILE *f;

  /* check avaibility of target server */
  i=Socket(proxyhost==NULL?host:proxyhost,proxyport);    //从这里可以选择是使用代理还是直接进行请求   这个端口号只用proxyport
  if(i<0) { 
	   fprintf(stderr,"\nConnect to server failed. Aborting benchmark.\n");
           return 1;
         }
  close(i);      //用来测试是否能连接到目标主机
  /* create pipe */
  if(pipe(mypipe))
  {
	  perror("pipe failed.");
	  return 3;
  }

  /* not needed, since we have alarm() in childrens */
  /* wait 4 next system clock tick */
  /*
  cas=time(NULL);
  while(time(NULL)==cas)
        sched_yield();
  */

  /* fork childs */
  for(i=0;i<clients;i++)      //创建client个子进程
  {
	   pid=fork();
	   if(pid <= (pid_t) 0)
	   {
		   /* child process or error*/
	           sleep(1); /* make childs faster */
		   break;
	   }
  }

  if( pid< (pid_t) 0)   
  {
          fprintf(stderr,"problems forking worker no. %d\n",i);
	  perror("fork failed.");
	  return 3;
  }

  if(pid== (pid_t) 0)   //表示子进程
  {
    /* I am a child */
    if(proxyhost==NULL)
      benchcore(host,proxyport,request);   //表示用来发送请求的
         else
      benchcore(proxyhost,proxyport,request);   //表示用来发送请求的

         /* write results to pipe */
	 f=fdopen(mypipe[1],"w");     //子进程写管道
	 if(f==NULL)
	 {
		 perror("open pipe for writing failed.");
		 return 3;
	 }
	 /* fprintf(stderr,"Child - %d %d\n",speed,failed); */
	 fprintf(f,"%d %d %d\n",speed,failed,bytes);    //子进程将自己的访问状况发送给父进程
	 fclose(f);
	 return 0;       //子进程结束
  } else     //父进程  也是主进程
  {
	  f=fdopen(mypipe[0],"r");   //读取子进程发送来的信息
	  if(f==NULL) 
	  {
		  perror("open pipe for reading failed.");
		  return 3;
	  }
	  setvbuf(f,NULL,_IONBF,0);
	  speed=0;
          failed=0;
          bytes=0;
    /*
      这些变量在父进程和子进程都是独立的 不是共享的    子进程和父进程有互不关联的空间    因此这些在子进程中变量的改变不影响父进程的变量
    */
	  while(1)
	  {
		  pid=fscanf(f,"%d %d %d",&i,&j,&k);    //表示从子进程来读信息
		  if(pid<2)
                  {
                       fprintf(stderr,"Some of our childrens died.\n");
                       break;
                  }
		  speed+=i;
		  failed+=j;
		  bytes+=k;      //从子进程读取信息后将所有的子进程信息进行回合
		  /* fprintf(stderr,"*Knock* %d %d read=%d\n",speed,failed,pid); */
		  if(--clients==0) break;    //执行一个循环表示结束一个子进程，因为只有子进程结束后才会向父进程发送信息 当client=0时表示子进程都结束了
	  }
	  fclose(f);

  printf("\nSpeed=%d pages/min, %d bytes/sec.\nRequests: %d susceed, %d failed.\n",
		  (int)((speed+failed)/(benchtime/60.0f)),
		  (int)(bytes/(float)benchtime),
		  speed,
		  failed);       //最后输出结果
  }
  return i;
}


/*

下面这个函数是每个子进程和服务器进行通信的具体过程
*/
void benchcore(const char *host,const int port,const char *req)
{
 int rlen;
 char buf[1500];
 int s,i;
 struct sigaction sa;

 /* setup alarm signal handler */
 sa.sa_handler=alarm_handler;
 sa.sa_flags=0;
 if(sigaction(SIGALRM,&sa,NULL))
    exit(3);
 alarm(benchtime);     //当benchtime时间时会想本进程发送SIGALRM来结束进程

 rlen=strlen(req);
 nexttry:while(1)
 {
    if(timerexpired)
    {
       if(failed>0)
       {
          /* fprintf(stderr,"Correcting failed by signal\n"); */
          failed--;
       }
       return;
    }
    s=Socket(host,port);    //创建一个连接                      
    if(s<0) { failed++;continue;}    //表示创建失败
    if(rlen!=write(s,req,rlen)) {failed++;close(s);continue;}
    if(http10==0) 
	    if(shutdown(s,1)) { failed++;close(s);continue;}
    if(force==0) 
    {
            /* read all available data from socket */
	    while(1)
	    {
              if(timerexpired) break; 
	      i=read(s,buf,1500);
              /* fprintf(stderr,"%d\n",i); */
	      if(i<0) 
              { 
                 failed++;
                 close(s);
                 goto nexttry;
              }
	       else
		       if(i==0) break;
		       else
			       bytes+=i;
	    }
    }
    if(close(s)) {failed++;continue;}
    speed++;
 }
}