C.前面看了一大段是不是有点云里雾里的啊?是有点罗嗦,但是俗话说:“万事总是开头难”OK,现在总算可以写主程序文件了。
下面就是ant.c文件
#include "ant.h"
#include "signal.h"
//0表示不用,1表示用代理
int use_proxy;
//代理服务器的地址
char proxy_server[100];
//端口
u_short proxy_port;
//蚂蚁数目
int ant_num;
//下载量
int bulk;
//下载进程
int progress;
char cfgfile[256];
char logfile[256];
struct Ant* ants[10];
struct Mission ms;
//响应异常退出,将url、ant数据结构中的变量值,存放到log文件。
void justpause()
{
int i;
FILE* log;
log=fopen(logfile,"w");
fprintf(log,"%s ",ms.url);
for(i=0;iamount!=0)
fprintf(log, "%d:%d ",ants[i]-position,ants[i]-amount);
fclose(log);
exit(1);
}
//总算挨到主程序了,呵呵。。。。。
int main(int argc,char** argv)
{
int n;
int maxfd;
char savefile[256];
FILE* goods;
FILE* log;
fd_set rset,aset;
int finished;
int length;
char status[80];
char c;
struct sigaction sa;
//初始化环境参数
init_env( );
//对命令行传进来的参数做判断
while((c=getopt(argc,argv,"n:u:s:p:l:h"))!=EOF){
switch (c){
//取得蚂蚁数目
case 'n':
ant_num=atoi(optarg);
if(ant_num MAXANTNUM)
ant_num = MAXANTNUM;
break;
//取得目标的url地址。
case 'u':
strcpy(ms.url, optarg);
break;
//取得代理的地址
case 's':
strcpy(proxy_server, optarg);
use_proxy=1;
break;
//取得代理的端口
case 'p':
use_proxy=1;
proxy_port=(u_short)atoi(optarg);
break;
//取得日志文件名
case 'l':
strcpy(logfile,optarg);
break;
case 'h':
printf("usage: ant -n antnum -u url -s proxyserver -p
prxoy_port -l logfile ");
return 1;
}
}
//从日志文件中读取url
if(logfile[0] != 0){
log = fopen(logfile, "r+");
strcpy(ms.url,get_url_from_log(log));
}
//将值赋代理服务器的相关变量
if(use_proxy){
strcpy(ms.host,proxy_server);
ms.port=proxy_port;
}else{
strcpy(ms.host, extract_from_url(ms.url, SITENAME));
ms.port = atoi(extract_from_url(ms.url, PORTNAME));
}
//如果有下载日志,从日志中取相关信息
if(logfile[0] != 0){
printf("The file you havent download,continue.......");
n=0;
strcpy(ms.url,get_url_from_log(log));
while (1) {
ants[n] = (struct Ant*)malloc(sizeof(struct Ant));
memset(ants[n], 0, sizeof(struct Ant));
if(!(assign_mission(log, ants[n])))
break;
n++;
if(n MAXANTNUM){
printf("You logfile must be wrong! ");
exit(1);
}
}
fclose(log);
free(ants[n]);
ant_num=n;
}
else{
//取得下载文件的大小,为每只蚂蚁分配下载位置。
bulk=get_size_of_url(&ms);
if(bulk==0){
printf("Cannot get the size of this object! ");
ant_num=1;
ants[0] = (struct Ant*)malloc(sizeof(struct Ant));
ants[0]-position=0;
ants[0]-amount=1073741823;
}
else if(bulk==-1){
printf("Cannot connect to the site! ");
exit(1);
}
else{
for(n=0; nposition = (bulk/ant_num)*n;
if(n!=(ant_num-1))
ants[n]-amount = bulk/ant_num;
else
ants[n]-amount = bulk-(bulk/ant_num)*(ant_num-1);
}
}
}
//}
maxfd=0;
//重设&rset
FD_ZERO(&rset);
//下载,按蚂蚁数开线程
for(n=0; nants[n]-s?maxfd:ants[n]-s;
}
}
if(!maxfd){
printf("no ant go work! ");
return 1;
}
memset(&sa,0,sizeof(struct sigaction));
//打开存储文件
strcpy(savefile, extract_from_url(ms.url, FILENAME));
if(!(goods=fopen(savefile, "r+"))){
if(!(goods=fopen(savefile,"w"))){
printf("Can not open file to save . ");
exit(1);
}
}
strcpy(logfile, savefile);
strcat(logfile, ".log");
//处理进程改变
sa.sa_handler=justpause;
sa.sa_flags=SA_ONESHOT;
sigaction(SIGINT, &sa, NULL);
maxfd++;
finished = 0;
progress = 0;
printf(" ");
printf("Downloading ....................now! ");
while(1){
if(finished==ant_num){
break;
}
aset=rset;
select(maxfd,&aset,NULL,NULL,NULL);
for(n=0;ns,&aset)){
if(!(length=receive(ants[n], goods))){
unenroll(ants[n], &rset);
finished++;
}
}
}
}
unlink(logfile);
log=(FILE*)NULL;
//打开日志文件
if(ant_num!=1){
for(n=0;namount){
if(!log){
log=fopen(logfile, "w+");
fputs(ms.url, log);
fputc(' ',log);
}
//保存状态
save_status(ants[n], log);
printf("Ant %d have not done!%d ",n+1,ants[n]-amount);
}
else
printf("Ant %d done! ", n+1);
free(ants[n]);
}
}
else
free(ants[0]);
fclose(goods);
if(log)
fclose(log);
return 1;
}
D.写完程序下面就是做makefile.程序比较小,所以MAKEFILE也比较简单:
CC = gcc
CFLAGS =
source=ant.h ant.c funcs.c
object=ant.o funcs.o
ant:$(object)
$(CC) $(object) -o $@
%o:%c
$(CC) -c $
bak:
tar czvf ant.tgz Makefile $(source)
rm -f $(object)
OK.到这总算飞到目的地了。现在你只要在命令行下用“make”命令就可以编译了。
4。教训
有一个错误,调了很久才发现,就是当fprintf(log,"%s ",ms.url)这样的语句的指针变量为空时,程序执行过程中就会发生“Segmentation fault (core dumped)”这样的错误。另外,由于程序没有多加判断,在输入url时,千万要带上“http://”或“ftp://”,哪位网友有兴趣可以自己修改。