Webbench是一个在Linux下使用的非常简单的网站侧压工具。它使用fork()模拟多个客户端同时访问url,测试网站在压力下工作的性能。 只有socket.c和webbench.c两个文件.
cd webbench
sudo make
sudo make install webbenchpath
./webbench -c 40 -t 10 -f --get http://www.baidu.com/index.html
父进程创建多个子进程,由每个子进程来创建socket连接,发送http请求,最后等时间到了之后,将数据写入管道. 然后父进程不断地从管道中读出数据,汇总结果输出.
//socket.c
/* $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>
int Socket(const char *host, int clientPort)
{
int sock;
unsigned long inaddr;
struct sockaddr_in ad;
struct hostent *hp;
/*
初始化地址
struct sockaddr_in{
short sin_family;//Address family一般来说AF_INET(地址族)PF_INET(协议族)
unsigned short sin_port;//Port number(必须要采用网络数据格式,普通数字可以用htons()函数转换成网络数据格式的数字)
struct in_addr sin_addr;//IP address in network byte order(Internet address)
unsigned char sin_zero[8];//Same size as struct sockaddr没有实际意义,只是为了 跟SOCKADDR结构在内存中对齐
};
struct in_addr {
in_addr_t s_addr;
};
in_addr_t 一般为 32位的unsigned int,其字节顺序为网络顺序(大端字节序)
*/
memset(&ad, 0, sizeof(ad));
//AF_INET(又称 PF_INET)是 IPv4 网络协议的套接字类型,两者有着相同的宏定义.
ad.sin_family = AF_INET;
//inet_addr() 将字符串形式的IP地址 -> 网络字节顺序 的整型值
inaddr = inet_addr(host);
//INADDR_NONE 是个宏定义,代表无效的IP地址
if (inaddr != INADDR_NONE)
memcpy(&ad.sin_addr, &inaddr, sizeof(inaddr));
else
{
/*
gethostbyname()通过名字获得主机的相关信息
返回值是一个结构体
struct hostent{
char *h_name;
char ** h_aliases;
short h_addrtype;
short h_length;
char ** h_addr_list;
};
*/
hp = gethostbyname(host);
if (hp == NULL)
return -1;
//此处用h_addr是因为有这样一个宏定义
//#define h_addr h_addr_list[0]
memcpy(&ad.sin_addr, hp->h_addr, hp->h_length);
}
/*
htons主机字节序 >> 网络字节序
主机:小端字节序
网络:大端字节序
htonl()--"Host to Network Long"
ntohl()--"Network to Host Long"
htons()--"Host to Network Short"
ntohs()--"Network to Host Short"
*/
ad.sin_port = htons(clientPort);
/*
socket()函数用于根据指定的地址族、数据类型和协议来分配一个套接口的描述字及其所用的资源。
SOCK_STREAM 提供有序的、可靠的、双向的和基于连接的字节流,使用带外数据传送机制,为Internet地址族使用TCP。
SOCK_DGRAM 支持无连接的、不可靠的和使用固定大小(通常很小)缓冲区的数据报服务,为Internet地址族使用UDP。
*/
sock = socket(AF_INET, SOCK_STREAM, 0);
if (sock < 0)
return sock;
//connect()用于建立与指定socket的连接。
if (connect(sock, (struct sockaddr *)&ad, sizeof(ad)) < 0)
return -1;
return sock;
}
webbench.c
webbench.c
/*
* (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 防止编译器对代码进行优化
//如果到达规定的时间,把该变量置1
volatile int timerexpired=0;
//存储成功的http请求数,最后除以时间,就得到速度.
int speed=0;
//存储失败http连接数
int failed=0;
//传输过的字节数
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;
//如果命令行参数加了-f,就会将force置1,代表忽略返回的数据
int force=0;
//强制加载,如果添加-r参数,会置1,会将http的pragma字段设置为no-cache,即不使用缓存
int force_reload=0;
int proxyport=80;
char *proxyhost=NULL;
int benchtime=30;
//父子进程用来通信的管道
/* internal */
int mypipe[2];
char host[MAXHOSTNAMELEN];
#define REQUEST_SIZE 2048
char request[REQUEST_SIZE];
/*
struct option指明了一个“长参数”(即形如--name的参数)名称和性质
struct option {
const char *name; 参数名
int has_arg; 0-无参数 1-后面一定跟个参数 2-可跟可不跟
int *flag; 用来决定getopt_long()的返回值是什么,flag是null,则函数会返回与该项option匹配的val值
参数不为空,那么当选中某个长选项的时候,getopt_long将返回0,并且将flag指针参数指向val值
int val; 和flag联合决定返回值
}
*/
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}
};
/* prototypes原型 */
static void benchcore(const char* host,const int port, const char *request);
static int bench(void);
static void build_request(const char *url);
//子进程中的信号处理函数
static void alarm_handler(int signal)
{
timerexpired=1;
}
//用法
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)
{
usage();
return 2;
}
/*
命令行参数可以分为两类,一类是短选项,一类是长选项,短选项在参数前加一杠"-",长选项在参数前连续加两杠"--"
getopt函数只能处理短选项,而getopt_long函数两者都可以
int getopt_long(int argc,char* const argv[],const char *optstring,const struct option *longopts,int *longindex);
optstring: 表示短选项字符串
形式如“a:b::cd:“,分别表示程序支持的命令行短选项有-a、-b、-c、-d,冒号含义如下:
(1)只有一个字符,不带冒号——只表示选项,如-c
(2)一个字符,后接一个冒号——表示选项后面带一个参数,如-a 100
(3)一个字符,后接两个冒号——表示选项后面带一个可选参数,即参数可有可无,如果带参数,则选项与参数直接不能有空格如-b200
*/
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':
/* proxy server parsing server:port */
// strrchr(const char *str, int c)
// 在参数str所指向的字符串中搜索最后一次出现字符c(一个无符号字符)的位置,如果未找到该值,则函数返回一个空指针
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';
//把字符串转换为一个整数
proxyport=atoi(tmp+1);break;
case ':':
case 'h':
case '?': usage();return 2;//break; 这里的break永远不会执行到呀
case 'c': clients=atoi(optarg);break;
}
}
//optind:表示的是下一个将被处理到的参数在argv中的下标值。
if(optind==argc) {
fprintf(stderr,"webbench: Missing URL!\n");
usage();
return 2;
}
if(clients==0) clients=1;
if(benchtime==0) benchtime=30;
/* Copyright */
fprintf(stderr,"Webbench - Simple Web Benchmark "PROGRAM_VERSION"\n"
"Copyright (c) Radim Kolar 1997-2004, GPL Open Source Software.\n"
);
//构造http的请求消息
build_request(argv[optind]);
// print request info ,do it in function build_request
/*printf("Benchmarking: ");
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");
*/
printf("Runing info: ");
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();
}
//用来创建http的请求
void build_request(const char *url)
{
char tmp[10];
int i;
//bzero(host,MAXHOSTNAMELEN);
//bzero(request,REQUEST_SIZE);
memset(host,0,MAXHOSTNAMELEN);
memset(request,0,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,"://"))
{
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 (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;
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,'/'))
{
strncpy(host,url+i,strchr(url+i,':')-url-i);
//bzero(tmp,10);
memset(tmp,0,10);
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);
}
if(http10==1)
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("\nRequest:\n%s\n",request);
}
//用来创建多个子进程,然后每个子进程会分别调用benchcore函数对服务器进行测试.
/* vraci system rc error kod */
static int bench(void)
{
int i,j,k;
pid_t pid=0;
FILE *f;
//先测试一下此网址是否正常.
/* 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)
{
//子进程
/* I am a child */
if(proxyhost==NULL)
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;
}
//向管道写入小于PIPE_BUF的数据的操作可以保证是原子的
/* fprintf(stderr,"Child - %d %d\n",speed,failed); */
fprintf(f,"%d %d %d\n",speed,failed,bytes);
fclose(f);
return 0;
}
else
{
//父进程
f=fdopen(mypipe[0],"r");
if(f==NULL)
{
perror("open pipe for reading failed.");
return 3;
}
/*
设置流的缓冲区
int setvbuf(FILE *stream, char *buf, int type, unsigned size);
type : 期望缓冲区的类型:
_IOFBF(满缓冲):当缓冲区为空时,从流读入数据。或者当缓冲区满时,向流写入数 据。
_IOLBF(行缓冲):每次从流中读入一行数据或向流中写入一行数据。
_IONBF(无缓冲):直接从流中读入数据或直接向流中写入数据,而没有缓冲区。
size : 缓冲区内字节的数量。
*/
setvbuf(f,NULL,_IONBF,0);
speed=0;
failed=0;
bytes=0;
//父进程不断地对管道进行读取,汇总每个子进程的测试结果.
while(1)
{
//当管道中无数据时,应该会阻塞吧
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;
}
//测试的核心函数,该函数在子进程中执行,不断地发送http请求,force==0就会接受数据,force!=0就忽略掉返回的数据.
//该函数给自己设置了个定时器,到达时间就会让自己把timeexpired置为1,然后会退出循环.
void benchcore(const char *host,const int port,const char *req)
{
int rlen;
char buf[1500];
int s,i;
/*
struct sigaction {
void (*sa_handler)(int); 信号处理函数
void (*sa_sigaction)(int, siginfo_t *, void *);
sigset_t sa_mask; 信号掩码,执行信号处理函数时将屏蔽这些信号
int sa_flags;
void (*sa_restorer)(void);
}
*/
struct sigaction sa;
/* setup alarm signal handler */
sa.sa_handler=alarm_handler;
sa.sa_flags=0;
//设置信号处理函数
if(sigaction(SIGALRM,&sa,NULL))
exit(3);
//设置定时器,benchtime之后就发送信号.
//unsigned int alarm(unsigned int seconds);
alarm(benchtime); // after benchtime,then exit
rlen=strlen(req);
//该循环负责不断地创建socket连接,然后给服务器发送http请求.
nexttry:while(1)
{
if(timerexpired)
{
if(failed>0)
{
/* fprintf(stderr,"Correcting failed by signal\n"); */
failed--;
}
return;
}
s=Socket(host,port);
//printf("socket discriptr: %d,getpid: %d.\n",s,getpid());
if(s<0) { failed++;continue;}
if(rlen!=write(s,req,rlen)) {failed++;close(s);continue;}
if(http10==0)
/*
禁止在一个套接口上进行数据的接收与发送。
int shutdown(int sockfd,int how);
s:用于标识一个套接口的描述字。
how:标志,用于描述禁止哪些操作。
how的方式有三种分别是
SHUT_RD(0):关闭sockfd上的读功能,此选项将不允许sockfd进行读操作。
SHUT_WR(1):关闭sockfd的写功能,此选项将不允许sockfd进行写操作。
SHUT_RDWR(2):关闭sockfd的读写功能。
*/
if(shutdown(s,1)) { failed++;close(s);continue;}
if(force==0)
{
/* read all available data from socket */
//该循环负责接受服务器返回的数据,如果force为1,则不接受数据
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++;
}
}