本文共 11895 字,大约阅读时间需要 39 分钟。
webbench是一个网站压力测试工具,使用fork模拟多个客户端来请求http get/post,统计发送接数据的字节数,默认超时60秒。
源码还是相对简单的,最主要是得了解http请求的协议,其实也不难就是用socket发送一些规范的字符串而已。
下面是对它的源码分析,全C的,效率应该是比较高的啦。
by shell.albert@gmail.com
/* $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> //参数为ip地址或域名,客户端端口号 //函数返回创建好的,已经连接上的socket文件描述符。 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; //将192.168.0.110类似的ip地址转换为网络字节保存起来。 inaddr = inet_addr(host); if (inaddr != INADDR_NONE) memcpy(&ad.sin_addr, &inaddr, sizeof(inaddr)); else { //域名到IP的转换,先查找/etc/hosts,再向DNS请求。 hp = gethostbyname(host); if (hp == NULL) return -1; memcpy(&ad.sin_addr, hp->h_addr, hp->h_length); } ad.sin_port = htons(clientPort); //创建一个TCP套接字。 sock = socket(AF_INET, SOCK_STREAM, 0); if (sock < 0) return sock; //这里为什么要连接??难道这个函数是为client准备的??? if (connect(sock, (struct sockaddr *)&ad, sizeof(ad)) < 0) return -1; return sock; } /* * (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]; //通过man getopt可以查到这个结构体的具体定义 //第1个参数为name,第2个为:no_argument(0),required_argument(1),optional_argument(2). //第3个为保存的值,第4个为返回的值。 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} //规定必须以0结束! }; /* 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; //检测参数 if(argc==1) { usage(); return 2; } //循环处理命令行的参数,设置相关的条件变量,将设置的参数保存的变量中以备后面使用。 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);//显示版本信息退出 case 't': benchtime=atoi(optarg);break; case 'p': /* proxy server parsing server:port */ tmp=strrchr(optarg,':'); proxyhost=optarg; 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; case ':': case 'h': case '?': usage();return 2;break;//这里的h和?应该为了显示帮助信息。 case 'c': clients=atoi(optarg);break; } } //optind是argv的索引值,每次会从0~argc-1变化。 //如果optind等于argc了,则说明没有提供URL参数。(参数个数少1个)。 if(optind==argc) { fprintf(stderr,"webbench: Missing URL!\n"); usage(); return 2; } //防御性编程,如果没有提供值则强制使用默认值。 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" ); 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();//还有这种写法呀?? 俺以前没这么写过,可以省一个中间变量的空间吗? } //这是创建一个请求吗???? 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; //要求不同的方法,使用不同的请求关键字,这应该是http协议规定的吧。 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; } //要用空格分隔呀 strcat(request," "); //查找字符串,如果传进来的不是标准的,则出错,一般为http://www.yantai.com.cn. if(NULL==strstr(url,"://")) { fprintf(stderr, "\n%s: is not a valid URL.\n",url); exit(2); } //这应该也是防御性编程吧,url应该不会这么长!如果太长了,会导致创建请求溢出! if(strlen(url)>1500) { fprintf(stderr,"URL is too long.\n"); exit(2); } if(proxyhost==NULL) //忽略大小写的比较,比较前7个字符是不是标准的http协议开头的。 if (0!=strncasecmp("http://",url,7)) { fprintf(stderr,"\nOnly HTTP protocol is directly supported, set --proxy for others.\n"); exit(2); } /* protocol/host delimiter */ i=strstr(url,"://")-url+3; /* printf("%d\n",i); */ //判断后面是不是www.baidu.com/,这真是奇巴呀! 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 */ //index()在一个字符串中查找一个字符的位置,以前还真没使用过这个函数呀! if(index(url+i,':')!=NULL && index(url+i,':')<index(url+i,'/')) { strncpy(host,url+i,strchr(url+i,':')-url-i); bzero(tmp,10); strncpy(tmp,index(url+i,':')+1,strchr(url+i,'/')-index(url+i,':')-1); /* printf("tmp=%s\n",tmp); */ proxyport=atoi(tmp); 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); //追加字符串。 } if(http10==1) strcat(request," HTTP/1.0"); //追加字符串 else if (http10==2) strcat(request," HTTP/1.1"); //追加字符串 strcat(request,"\r\n"); //追加回车换行符 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("build Req=%s\n",request); //创建出来的请求字符串,打印出下,拷贝过来的。 //GET / HTTP/1.0 //User-Agent: WebBench 1.5 //Host: www.baidu.com //这应该是http协议规定的吧.不过这里的回车换行符为\r\n. } /* vraci system rc error kod */ static int bench(void) { int i,j,k; pid_t pid=0; FILE *f; //使用tcp socket连接到服务器上。 /* 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 */ //创建管道有什么用呀??一端写,一端读吗? 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 */ //创建好几个进程! 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) benchcore(host,proxyport,request); else benchcore(proxyhost,proxyport,request); /* write results to pipe */ //fdopen能将一个fd跟FILE*关联,使用流来操作! f=fdopen(mypipe[1],"w"); if(f==NULL) { perror("open pipe for writing failed."); return 3; } /* fprintf(stderr,"Child - %d %d\n",speed,failed); */ //这是往流中写入数据呀!!! fprintf(f,"%d %d %d\n",speed,failed,bytes); fclose(f); return 0; } else { //将管道的读端与流关联! f=fdopen(mypipe[0],"r"); if(f==NULL) { perror("open pipe for reading failed."); return 3; } setvbuf(f,NULL,_IONBF,0); //无缓冲。 speed=0; failed=0; bytes=0; while(1) { 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); 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; } 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); rlen=strlen(req); nexttry:while(1) { if(timerexpired) { if(failed>0) { /* fprintf(stderr,"Correcting failed by signal\n"); */ failed--; } return; } s=Socket(host,port); if(s<0) { failed++;continue;} //向服务器发送请求字符串。 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) //反复读取服务器的返回 { if(timerexpired) break; i=read(s,buf,1500); fprintf(stderr,"%s\n",buf); if(i<0) { failed++; close(s); goto nexttry; } else if(i==0) break; else bytes+=i; //累加读回的值。 } } if(close(s)) {failed++;continue;} speed++; } }转载地址:http://wczji.baihongyu.com/