⭐ 欢迎来到虫虫下载站！ | 📦 资源下载 📁 资源专辑 ℹ️ 关于我们
⭐ 虫虫下载站
📤 上传资源

📄 1041.html

📁 著名的linux英雄站点的文档打包
💻 HTML
📖 第 1 页 / 共 5 页
字号:
🔍
12345 
<br>
#define DAEMON_LOCK "/var/chess/daemon.lock"  <br>
#define DAEMON_LOG  "/var/chess/daemon.log"  <br>
#define DAEMON_PORT 9901  <br>
<br>
int DaemonSocket;  <br>
struct sockaddr_in DaemonAddr;  <br>
<br>
int ClientSocket=0;  <br>
struct sockaddr_in HostAddr;  <br>
<br>
void dlog(char *fmt,...)  <br>
{  <br>
  va_list argptr;  <br>
  FILE *fp;  <br>
<br>
  fp = fopen(DAEMON_LOG,"a+t");  <br>
  va_start(argptr,fmt);  <br>
  vfprintf(fp,fmt,argptr);  <br>
  va_end(argptr);  <br>
  fclose(fp);  <br>
}  <br>
<br>
pid_t CheckLock(void)  <br>
{  <br>
  pid_t me;  <br>
  FILE * fp;  <br>
<br>
  fp = fopen(DAEMON_LOCK,"rt");  <br>
  if (fp==NULL) return 0;  <br>
  fscanf(fp,"%d",&me);  <br>
  fclose(fp);  <br>
<br>
  return me;  <br>
}  <br>
<br>
pid_t WriteLock(void)  <br>
{  <br>
  pid_t me;  <br>
  FILE *fp;  <br>
<br>
  me = getpid();  <br>
<br>
  fp = fopen(DAEMON_LOCK,"w");  <br>
  fprintf(fp,"%d",me);  <br>
  fclose(fp);  <br>
<br>
  return me;  <br>
}  <br>
<br>
int CleanLock(void)  <br>
{  <br>
  return (unlink(DAEMON_LOCK)==0);  <br>
}  <br>
<br>
void report_time(void)  <br>
{  <br>
  time_t now;  <br>
  now = time(NULL);  <br>
  dlog("%s",asctime((const struct tm*)localtime(&now)));  <br>
}  <br>
<br>
static void signal_catch(int signo)  <br>
{  <br>
  time_t now;  <br>
<br>
  close(DaemonSocket);  <br>
  if (ClientSocket&gt;0) close(ClientSocket);  <br>
  CleanLock();  <br>
  now = time(NULL);  <br>
  dlog("Catch signal %d, leave at %s",signo,asctime((const struct tm*)localti  <br>
  exit(-1);  <br>
}  <br>
<br>
void SetupSignal(void)  <br>
{  <br>
  struct sigaction act;  <br>
<br>
  act.sa_handler = signal_catch;  <br>
  act.sa_flags   = 0;  <br>
  sigemptyset(&act.sa_mask);  <br>
  sigaction(SIGHUP,&act,NULL);  <br>
  sigaction(SIGINT,&act,NULL);  <br>
  sigaction(SIGQUIT,&act,NULL);  <br>
  sigaction(SIGILL,&act,NULL);  <br>
  sigaction(SIGABRT,&act,NULL);  <br>
  sigaction(SIGIOT,&act,NULL);  <br>
  sigaction(SIGBUS,&act,NULL);  <br>
  sigaction(SIGFPE,&act,NULL);  <br>
  sigaction(SIGTERM,&act,NULL);  <br>
}  <br>
<br>
int BindSocket(void)  <br>
{  <br>
<br>
  DaemonSocket = socket(AF_INET,SOCK_STREAM,0);  <br>
  if (DaemonSocket==-1) return 0;  <br>
  DaemonAddr.sin_family = AF_INET;  <br>
  DaemonAddr.sin_port   = htons(DAEMON_PORT);  <br>
  if (bind(DaemonSocket,&DaemonAddr,sizeof(DaemonAddr))&lt;0) {  <br>
    printf("Can not bind!");  <br>
    return 0;  <br>
  }  <br>
  if (listen(DaemonSocket,1024)!=0) {  <br>
    printf("Can not listen!");  <br>
    return 0;  <br>
  }  <br>
<br>
  return 1;  <br>
}  <br>
<br>
int incoming_call(void)  <br>
{  <br>
  fd_set sock;  <br>
  struct timeval tv;  <br>
  int t;  <br>
<br>
  FD_ZERO(&sock);  <br>
  FD_SET(DaemonSocket,&sock);  <br>
  tv.tv_sec = 60; tv.tv_usec = 0;  <br>
  t = select(DaemonSocket + 1,&sock,NULL,NULL,&tv);  <br>
  if (t&lt;=0||!FD_ISSET(DaemonSocket,&sock)) return 0;  <br>
<br>
  dlog("incoming...");  <br>
<br>
  return 1;  <br>
}  <br>
<br>
int ConnectClient(void)  <br>
{  <br>
  int socksize=sizeof(HostAddr);  <br>
  unsigned char * addr;  <br>
<br>
  ClientSocket = accept(DaemonSocket,(struct sockaddr*)&HostAddr,&socksize);  <br>
  if (ClientSocket&lt;0) return 0;  <br>
<br>
  addr = (unsigned char *)&HostAddr.sin_addr.s_addr;  <br>
<br>
  dlog("incoming address:%d.%d.%d.%d",addr[0],addr[1],addr[2],addr[3]);  <br>
<br>
  return 1;  <br>
}  <br>
<br>
int daemon_printf(char *fmt,...)  <br>
{  <br>
  char BUF[4096];  <br>
  va_list argptr;  <br>
<br>
  va_start(argptr,fmt);  <br>
  vsprintf(BUF,fmt,argptr);  <br>
  va_end(argptr);  <br>
  return write(ClientSocket,BUF,strlen(BUF));  <br>
}  <br>
<br>
void Log(void)  <br>
{  <br>
  char BUF[4096];  <br>
  read(DaemonSocket,BUF,16);  <br>
  daemon_printf("%s",BUF[0]);  <br>
}  <br>
<br>
int main(int argc,char **argv)  <br>
{  <br>
  pid_t myself;  <br>
  time_t now;  <br>
<br>
  /* find myself */  <br>
  myself = CheckLock();  <br>
  if (myself!=0) {  <br>
    printf("Existing a copy of chess daemon[pid=%d], leave now.",myself);  <br>
    exit(1);  <br>
  }  <br>
<br>
  /* fork */  <br>
  myself = fork();  <br>
  if (myself&gt;0) {  <br>
    exit(1);  <br>
  } else  <br>
  if (myself&lt;0) {  <br>
    printf("Strange world! I don't like it. Quit because of pid=%d",myself);  <br>
    exit(1);  <br>
  } else {  <br>
    SetupSignal();  <br>
    if (!BindSocket()) {  <br>
      printf("Can not bind socket!");  <br>
      exit(1);  <br>
    }  <br>
    WriteLock();  <br>
  }  <br>
<br>
  printf("Chess Daemon is up, have fun!");  <br>
<br>
  now = time(NULL);  <br>
<br>
  dlog("----------------------------------------------");  <br>
  dlog(  <br>
    "I am back! %s"  <br>
    "Chess Daemon comes to alive again.",  <br>
    asctime((const struct tm*)localtime(&now))  <br>
  );  <br>
<br>
  do {  <br>
    if (incoming_call()) {  <br>
<br>
      if (ConnectClient()) {  <br>
<br>
        fd_set sock;  <br>
        struct timeval tv;  <br>
        int t;  <br>
        char BUF[128];  <br>
        char CC[2];  <br>
        int n;  <br>
<br>
          daemon_printf("Welcome to Chinese Chess Game Center!");  <br>
<br>
          FD_ZERO(&sock);  <br>
          FD_SET(ClientSocket,&sock);  <br>
          n = 0;  <br>
          do {  <br>
            tv.tv_sec = 60; tv.tv_usec = 0;  <br>
            t = select(ClientSocket+1,&sock,NULL,NULL,&tv);  <br>
            if (t&lt;=0||!FD_ISSET(ClientSocket,&sock)) ;  <br>
            read(ClientSocket,CC,1);  <br>
            if (CC[0]==13||CC[0]==10||CC[0]==0) {  <br>
              BUF[n] = 0;  <br>
              dlog("%s",BUF);  <br>
              if (strncasecmp(BUF,"exit",4)==0) {  <br>
                close(ClientSocket);  <br>
                break;  <br>
              }  <br>
              n = 0;  <br>
            } else {  <br>
              BUF[n]=CC[0]; n++;  <br>
            }  <br>
          } while (1);  <br>
      }  <br>
    }  <br>
  } while (1);  <br>
<br>
  return 1;  <br>
}  <br>
<br>
检验 <br>
telnet localhost 9901  <br>
   <br>
在处理Connect Client时，事实上可以运用fork或thread来处理多个连线。  <br>
 <br>
 <br>
Linux程式设计- 5.inetd <br>
http://www.openchess.org/noitatsko/programming/ (2001-05-24 18:08:00) <br>
inetd提供被动式的伺服器服务，也就是伺服器是被使用端所启动，平时则无须存在。例如，ftp, telnetd, pop3,imap, auth等等，这些服务没有人使用时，无须启动。此外，inetd将socket转换成stdin/stdout，因而使得网路服务程式设计大大简化，您可以只用printf及fgets便可完成处理很复杂的网路协定。  <br>
<br>
-------------------------------------------------------------------------------- <br>
<br>
inetd programming <br>
利用inetd来做网路程式设计是个既简单又稳定的设计方法，您不需要考虑到复杂的socket programming。您的设计工作几乎在设计好通讯协定後就完成了，所需要的技巧，仅为简单的文字分析技巧。  <br>
goodie inet service <br>
首先，我们先来撰写一个称为goodie的服务程式。  <br>
goodie.c  <br>
#include   <br>
#include   <br>
#include   <br>
<br>
void main(void)  <br>
{  <br>
  printf("Welcome to goodie service!");  <br>
}  <br>
<br>
这个程式很简单，不是吗?  <br>
<br>
编译 <br>
gcc -o goodie goodie.c  <br>
设定/etc/services及/etc/inetd.conf <br>
在/etc/services中加入以下这一行  <br>
goodie          20001/tcp  <br>
<br>
其意义为goodie这项服务是在port 20001、TCP协定。  <br>
<br>
接下来在/etc/inetd.conf中加入以下这一行  <br>
<br>
goodie stream tcp nowait root /full_goodie_path_name/goodie  <br>
<br>
各项参数的意义为  <br>
        <br>
<br>
service_name需要为在services中存在的名称。  <br>
sock_type有很多种，大多用的是stream/dgram。  <br>
proto一般用tcp/udp。  <br>
flags有wait/nowait。  <br>
user是您指定该程式要以那一个使用者来启动，这个例子中用的是root，如果有安全性的考量，应该要改用nobody。一般来说，建议您用低权限的使用者，除非必要，不开放root使用权。  <br>
server_path及args，这是您的服务程式的位置及您所想加入的参数。  <br>
<br>
接下来重新启动inetd  <br>
<br>
killall inetd  <br>
inetd  <br>
<br>
这样我们便建立起一个port 20001的goodie service。  <br>
现在我们来检验一下goodie是否可以执行:  <br>
<br>
telnet localhost 20001  <br>
或  <br>
telnet your_host_name 20001  <br>
<br>
执行结果 <br>
Trying 127.0.0.1...  <br>
Connected to localhost.  <br>
Escape character is '^]'.  <br>
Welcome to goodie service!  <br>
Connection closed by foreign host.  <br>
很简单不是吗? 信不信由您，telnet/pop3/imap/ftp都是靠这种方式建立起来的服务。  <br>
<br>
我们现在来建立一点小小的"网路协定"，这个协定使我们可以输入"exit"时，离开程式，而其他的指令都是输出与输入相同的字串。  <br>
12345

⌨️ 快捷键说明

复制代码 Ctrl + C
搜索代码 Ctrl + F
全屏模式 F11
切换主题 Ctrl + Shift + D
显示快捷键 ?
增大字号 Ctrl + =
减小字号 Ctrl + -