observer.c

该程序使用/proc机制检查反映机器平均负载

/***************************************************************************
                          main.c  -  description
                             -------------------
    begin                : 一 4月  4 21:01:11 CST 2003
    copyright            : (C) 2003 by 张鸿烈
    Function             : 观察linux内核行为

/***************************************************************************/ 

#include <stdio.h>
#include <sys/time.h>
#define LB_SIZE 80
enum TYPE{STANDARD,SHORT,LONG};
FILE *thisProcFile;
struct timeval now;
enum TYPE reportType;
char repTypeName[16];
char *lineBuf;
int interval; 
int duration;
int iteration;
char c1,c2;

void sampleLoadAvg(){ //观察系统负荷
     int i=0;
     thisProcFile = fopen("/proc/loadavg","r");
     fgets(lineBuf,LB_SIZE+1,thisProcFile);
     while(*(lineBuf+i)==' ') ++i;//跳过前导空格
     printf("\nOne minute average ");
     while(*(lineBuf+i)!=' ') {printf("%c",*(lineBuf+i)); i++;}//显示行中第一字段
     while(*(lineBuf+i)==' ') ++i;//跳过前导空格
     printf("\nFive minute average ");
     while(*(lineBuf+i)!=' ') {printf("%c",*(lineBuf+i)); i++;}//显示行中第二字段
     while(*(lineBuf+i)==' ') ++i;//跳过前导空格
     printf("\nTen minute average ");
     while(*(lineBuf+i)!=' ') {printf("%c",*(lineBuf+i)); i++;}//显示行中第三字段
     while(*(lineBuf+i)==' ') ++i;//跳过前导空格
     printf("\nRunuing Task/Total Task ");
     while(*(lineBuf+i)!=' ') {printf("%c",*(lineBuf+i)); i++;}//显示行中第四字段
     while(*(lineBuf+i)==' ') ++i;//跳过前导空格
     printf("\nLast Process ID ");
     while(*(lineBuf+i)!='\0') {printf("%c",*(lineBuf+i)); i++;}//显示行中第五字段
     printf("\n");
     fclose(thisProcFile);
}
void sampleTime(){//观察系统启动时间
     long uptime,idletime;
     int  day,hour,minute,second;
     int  i,j;
     char temp[80];
 
      i=j=0;
      thisProcFile = fopen("/proc/uptime","r");
      fgets(lineBuf,LB_SIZE+1,thisProcFile);
      printf("%s\n",lineBuf);
      while(*(lineBuf+i)==' ') ++i;//跳过前导空格
      while(*(lineBuf+i)!=' ') { *(temp+j)=*(lineBuf+i); i++; j++;}//取行中第一字段
      *(temp+j)='\0';

      uptime = atoi(temp);//将启动时间的秒数转换为长整数
      day = uptime/(3600*24);//求出日数
      hour= uptime%(3600*24)/3600;//求出小时数
      minute=(uptime%(3600*24)%3600)/60;//求出分钟数
      second=uptime%60;//求出秒数
      printf("Time from Boot\n");
      printf("%d:%d:%d:%d\n\n",day,hour,minute,second);

      j=0;
      while(*(lineBuf+i)==' ') ++i;
      while(*(lineBuf+i)!='\0') { *(temp+j)=*(lineBuf+i); i++; j++;}//取行中第一字段
      *(temp+j)='\0';

      idletime = atoi(temp);//将启动时间的空闲秒数转换为长整数
      day = idletime/(3600*24);//求出日数
      hour= idletime%(3600*24)/3600;//求出小时数
      minute=(idletime%(3600*24)%3600)/60;//求出分钟数
      second=idletime%60;//求出秒数
      printf("Idle Time from Boot\n");
      printf("%d:%d:%d:%d\n\n",day,hour,minute,second);
      printf("System Efficiency=%f\n\n",(float)uptime/(float)idletime);
}

int main(int argc,char *argv[])
{

      lineBuf = (char *)malloc(LB_SIZE+1);
      reportType = STANDARD;
      strcpy(repTypeName,"Standard");
      if(argc >1){ 
	sscanf(argv[1],"%c%c",&c1,&c2);//取命令行选择符
	if(c1!='-'){
	   printf("usage:observer [-b] [-c] [-d int dur]\n");
	   exit(1);
	}
	if(c2 == 'b'){//观察部分B
          printf("******PART B **********\n");
          thisProcFile = fopen("/proc/meminfo","r"); //观察内存信息
           while(!feof(thisProcFile)){
              fgets(lineBuf,LB_SIZE+1,thisProcFile);
              printf("%s",lineBuf); 
           }
          printf("\n");
          fclose(thisProcFile);      
          sampleTime();
        }
        else if(c2=='c'){//观察部分C
           printf("******PART C**********\n");
	   thisProcFile = fopen("/proc/stat","r");
           while(!feof(thisProcFile)){//取系统工作状态信息
              fgets(lineBuf,LB_SIZE+1,thisProcFile);
              printf("%s",lineBuf);
           }
           printf("\n");
          fclose(thisProcFile);
        }        
	else if(c2 == 'd'){ //观察部分 D
          printf("******PART D **********\n");
	  if(argc<4){
	     printf("usage:observer [-b] [-c][-d int dur]\n");
	     exit(1);
   	  }
	  reportType = LONG;
	  strcpy(repTypeName,"Long");
	  
          interval = atoi(argv[2]);//时间间隔
	  duration = atoi(argv[3]);//时间段
          iteration = 0;
          while(iteration<duration){
             sleep(interval);//睡眠一段时间
             sampleLoadAvg();//观察1,5,10分钟系统平均负荷
             iteration += interval;//加一个时间片
	   }    
       }
     }
     else{//观察部分B
      printf("******PART A **********\n");
      reportType = SHORT;
      strcpy(repTypeName,"Short");
      gettimeofday(&now,NULL);//取系统时间
      printf("Status report type %s at %s\n",
      repTypeName,ctime(&(now.tv_sec)));

      thisProcFile = fopen("/proc/sys/kernel/hostname","r");
      fgets(lineBuf,LB_SIZE+1,thisProcFile);//取机器名
      printf("Machine hostname:%s\n",lineBuf);
      fclose(thisProcFile);
    
      thisProcFile = fopen("/proc/cpuinfo","r");
      while(!feof(thisProcFile)){//取CPU信息
         fgets(lineBuf,LB_SIZE+1,thisProcFile);
         printf("%s",lineBuf);
      }
      printf("\n");
      fclose(thisProcFile);
      thisProcFile = fopen("/proc/version","r");
      while(!feof(thisProcFile)){//取OS版本号
           fgets(lineBuf,LB_SIZE+1,thisProcFile);
           printf("%s",lineBuf);
      }
      printf("\n");
      fclose(thisProcFile);
    }
}