Webbench原始碼分析

標籤：c   http測試   webbench   socket   

Web Bench是一個網站壓力測試的工具。其最後更新時間是2004年，已經十年多了。其原始碼總共才500多行，全部使用C語言編寫，最多可以類比上萬個並發串連。

其原理也比較簡單，就是使用fork建立子進程，通過子進程來測試http串連，把測試結果寫到管道，再有父進程讀取管道資訊來計算測試結果。流程圖下：

其原始碼有2個檔案組成

socket.c是建立socket串連的。主要的代碼在webbench.c中。

webbench.c中有幾個主要的函數。

static void usage(void)是在使用出錯時提示怎麼使用本程式。

void build_request(const char *url)是用來建立http串連請求的。

static int bench(void)中建立管道和子進程，調用測試http函數。

void benchcore(const char *host,const int port,const char *req)對http請求進行測試。

socket.c原始碼及注釋：

/* $Id: socket.c 1.1 1995/01/01 07:11:14 cthuang Exp $ * * This module has been modified by Radim Kolar for OS/2 emx *//***********************************************************************  module:       socket.c  program:      popclient  SCCS ID:      @(#)socket.c    1.5  4/1/94  programmer:   Virginia Tech Computing Center  compiler:     DEC RISC C compiler (Ultrix 4.1)  environment:  DEC Ultrix 4.3   description:  UNIX sockets code. ***********************************************************************/ #include <sys/types.h>#include <sys/socket.h>#include <fcntl.h>#include <netinet/in.h>#include <arpa/inet.h>#include <netdb.h>#include <sys/time.h>#include <string.h>#include <unistd.h>#include <stdio.h>#include <stdlib.h>#include <stdarg.h>/***********功能：通過地址和連接埠建立網路連接@host:網路地址@clientPort:連接埠Return：建立的socket串連。如果返回-1，表示建立串連失敗************/int Socket(const char *host, int clientPort){    int sock;    unsigned long inaddr;    struct sockaddr_in ad;    struct hostent *hp;        memset(&ad, 0, sizeof(ad));    ad.sin_family = AF_INET;    inaddr = inet_addr(host);//將點分的十進位的IP轉為無符號長整形    if (inaddr != INADDR_NONE)        memcpy(&ad.sin_addr, &inaddr, sizeof(inaddr));    else//如果host是網域名稱    {        hp = gethostbyname(host);//用網域名稱擷取IP        if (hp == NULL)            return -1;        memcpy(&ad.sin_addr, hp->h_addr, hp->h_length);    }    ad.sin_port = htons(clientPort);        sock = socket(AF_INET, SOCK_STREAM, 0);    if (sock < 0)        return sock;//串連    if (connect(sock, (struct sockaddr *)&ad, sizeof(ad)) < 0)        return -1;    return sock;}

wenbench.c原始碼及注釋

/* * (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 *///http協議的版本號碼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;//全域變數，指定http方法int clients=1;//並發數int force=0;//是否等待伺服器應答。預設為不等待int force_reload=0;int proxyport=80;//Proxy 伺服器連接埠號碼。預設為80char *proxyhost=NULL;//Proxy 伺服器的地址int benchtime=30;//運行多久。預設為30s。可以通過-t指定/* internal */int mypipe[2];char host[MAXHOSTNAMELEN];#define REQUEST_SIZE 2048char request[REQUEST_SIZE];//struct option結構體，配合getopt_long函數使用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;}/**************程式使用方法***************/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)//使用方法不合適 {  usage();          return 2; } //檢查輸入參數，並設定對應選項 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);//輸入版本號碼   case 't': benchtime=atoi(optarg);break;//optarg表示命令後的參數，例如-c 100，optarg為100。//atoi表示把字串轉換成長整型。   case 'p':      /* proxy server parsing server:port */     tmp=strrchr(optarg,':');     proxyhost=optarg;//設定地址     if(tmp==NULL)     {     break;     }     if(tmp==optarg)     {     fprintf(stderr,"Error in option --proxy %s: Missing hostname.\n",optarg);     return 2;     }     if(tmp==optarg+strlen(optarg)-1)     {     fprintf(stderr,"Error in option --proxy %s Port number is missing.\n",optarg);     return 2;     }     *tmp='\0';     proxyport=atoi(tmp+1);break;//重設連接埠號碼   case ':':   case 'h':   case '?': usage();return 2;break;   case 'c': clients=atoi(optarg);break;//並發數  } } //optind為對應參數的下標位置 if(optind==argc) {                      fprintf(stderr,"webbench: Missing URL!\n");      usage();      return 2;                    } if(clients==0) clients=1; if(benchtime==0) benchtime=60; /* Copyright */ fprintf(stderr,"Webbench - Simple Web Benchmark "PROGRAM_VERSION"\n" "Copyright (c) Radim Kolar 1997-2004, GPL Open Source Software.\n" );//使用中，最後為URL，所以optind應該是URL的位置 build_request(argv[optind]); /* print bench info */ printf("\nBenchmarking: "); switch(method) { 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"); return bench();}/****************建立URL請求串連@url:url地址建立好的請求放在全域變數request中****************/void build_request(const char *url){  char tmp[10];  int i;  //請求地址和請求串連清零  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;  case METHOD_HEAD: strcpy(request,"HEAD");break;  case METHOD_OPTIONS: strcpy(request,"OPTIONS");break;  case METHOD_TRACE: strcpy(request,"TRACE");break;  }    strcat(request," ");  if(NULL==strstr(url,"://"))//找“://”在URL中的位置  {  fprintf(stderr, "\n%s: is not a valid URL.\n",url);  exit(2);  }  if(strlen(url)>1500)//url是否太長  {         fprintf(stderr,"URL is too long.\n"); exit(2);  }  if(proxyhost==NULL)//Proxy 伺服器是否為空白   if (0!=strncasecmp("http://",url,7)) //比較前7個字串   { fprintf(stderr,"\nOnly HTTP protocol is directly supported, set --proxy for others.\n");             exit(2);           }  /* protocol/host delimiter */  i=strstr(url,"://")-url+3;//i指向http://後第一個位置  /* printf("%d\n",i); */  if(strchr(url+i,'/')==NULL) {                                fprintf(stderr,"\nInvalid URL syntax - hostname don't ends with '/'.\n");                                exit(2);                              }  if(proxyhost==NULL)  {   /* get port from hostname */   if(index(url+i,':')!=NULL &&      index(url+i,':')<index(url+i,'/'))//判斷url中是否指定了連接埠號碼   {   strncpy(host,url+i,strchr(url+i,':')-url-i);//取出主機地址   bzero(tmp,10);   strncpy(tmp,index(url+i,':')+1,strchr(url+i,'/')-index(url+i,':')-1);   /* printf("tmp=%s\n",tmp); */   proxyport=atoi(tmp);//連接埠號碼轉換為int   if(proxyport==0) proxyport=80;   } else   {     strncpy(host,url+i,strcspn(url+i,"/"));   }   // printf("Host=%s\n",host);   strcat(request+strlen(request),url+i+strcspn(url+i,"/"));  } else  {   // printf("ProxyHost=%s\nProxyPort=%d\n",proxyhost,proxyport);   strcat(request,url);  }  if(http10==1)//版本號碼  strcat(request," HTTP/1.0");  else if (http10==2)  strcat(request," HTTP/1.1");  strcat(request,"\r\n");  if(http10>0)  strcat(request,"User-Agent: WebBench "PROGRAM_VERSION"\r\n");  if(proxyhost==NULL && http10>0)  {  strcat(request,"Host: ");  strcat(request,host);  strcat(request,"\r\n");  }  if(force_reload && proxyhost!=NULL)  {  strcat(request,"Pragma: no-cache\r\n");  }  if(http10>1)  strcat(request,"Connection: close\r\n");  /* add empty line at end */  if(http10>0) strcat(request,"\r\n");   // printf("Req=%s\n",request);}/* vraci system rc error kod *//**********************建立管道和子進程，對http請求進行測試**********************/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);  if(i<0) {    fprintf(stderr,"\nConnect to server failed. Aborting benchmark.\n");           return 1;         }  close(i);  /* 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++)  {   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)  {    /* I am a child */    if(proxyhost==NULL)//是否使用proxyhost      benchcore(host,proxyport,request);         else      benchcore(proxyhost,proxyport,request);         /* write results to pipe */ f=fdopen(mypipe[1],"w"); 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);//把每個子進程啟動並執行結果放到管道。 fclose(f); return 0;  } else  {  f=fdopen(mypipe[0],"r");  if(f==NULL)   {  perror("open pipe for reading failed.");  return 3;  }  setvbuf(f,NULL,_IONBF,0);  speed=0;          failed=0;          bytes=0;  while(1)//父進程讀取管道資料，並做加法  {  pid=fscanf(f,"%d %d %d",&i,&j,&k);  if(pid<2)                  {                       fprintf(stderr,"Some of our childrens died.\n");                       break;                  }  speed+=i;  failed+=j;  bytes+=k;  /* fprintf(stderr,"*Knock* %d %d read=%d\n",speed,failed,pid); */  if(--clients==0) break;  }  fclose(f);  //輸出測試結果  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);  }  return i;}/******************************這裡才是測試http的地方@host:地址@port：連接埠@req：http格式方法********************************/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;//定時器方法 sa.sa_flags=0; if(sigaction(SIGALRM,&sa,NULL))    exit(3); alarm(benchtime); rlen=strlen(req); nexttry:while(1) {    if(timerexpired)//定時器到時後，會設定timerexpired=1，函數就會返回    {       if(failed>0)       {          /* fprintf(stderr,"Correcting failed by signal\n"); */          failed--;       }       return;    }    s=Socket(host,port);      //建立串連                        if(s<0) { failed++;continue;} //串連失敗，failed加1    if(rlen!=write(s,req,rlen)) {failed++;close(s);continue;}//發送失敗    if(http10==0)     if(shutdown(s,1)) { failed++;close(s);continue;}    if(force==0) //force等於0表示要讀取http請求資料    {            /* 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;//讀取位元組數增加    }    }    if(close(s)) {failed++;continue;}    speed++;//http測試成功一次，speed加1 }}

Webbench原始碼分析