test libvirt

/****************************************************************
*filename:myvm.c
*author:hemmingway
time:2012年05月25日星期五 17时46分39秒
*compile with:gcc -g -Wall myvm.c -o myvm -lvirt
****************************************************************/

#include <stdio.h>
#include <stdlib.h>
#include <libvirt/libvirt.h>

#define MAXID 50

/*the data strucure of time*/
typedef struct _timeInfo
{
long long cpu_time;
struct timeval real_time;
}TIMEINFONODE;

/*the hypervisor connection*/
static virConnectPtr conn = NULL;

/*release the connecton of hypervisor*/
void closeConn()
{
if(conn != NULL)
virConnectClose(conn);
}

/*release the domain pointer*/
void freeDom(virDomainPtr dom)
{
if(dom != NULL)
virDomainFree(dom);
}

/*get start time of each domain*/
void getTimeInfo(int id,TIMEINFONODE *infos)
{
virDomainPtr dom = NULL;
virDomainInfo info;
int ret;

/*find the domain of the given id*/
dom = virDomainLookupByID(conn,id);
if(NULL == dom)
  {
   fprintf(stderr,"failed to find domain by id \'%d\'.\n",id);
   freeDom(dom);
   closeConn();
  }

/*get the information of the domain*/
ret = virDomainGetInfo(dom,&info);
if(ret < 0) /*-1 ?*/
  {
   fprintf(stderr,"failed to get informaton for domain \'%d\'.\n",id);
   freeDom(dom);
   closeConn();
  }

/*retrive the start time*/
if(gettimeofday(&(infos->real_time),NULL) == -1)
  {
   fprintf(stderr,"oh my god!failed to get start time.\n");
   return;
  }

/**/
infos->cpu_time = info.cpuTime;

freeDom(dom);
}

void getDomainInfo(int id,TIMEINFONODE infos)
{
virDomainPtr dom = NULL;
virDomainInfo info;
int ret;

struct timeval realTime;
int cpu_diff,real_diff;
float usage;

  /*find the domain of the given id*/
dom = virDomainLookupByID(conn,id);
if(NULL == dom)
  {
   fprintf(stderr,"failed to find domain by id \'%d\'.\n",id);
   freeDom(dom);
   closeConn();
  }

/*get the information of the domain*/
ret = virDomainGetInfo(dom,&info);
if(ret < 0) /*-1 ?*/
  {
   fprintf(stderr,"failed to get informaton for domain \'%d\'.\n",id);
   freeDom(dom);
   closeConn();
  }

/*retrive the start time*/
if(gettimeofday(&(infos.real_time),NULL) == -1)
  {
   fprintf(stderr,"oh my god!failed to get start time.\n");
   return;
  }

  cpu_diff = (info.cpuTime - infos.cpu_time) / 10000;
  real_diff = 1000 * (realTime.tv_sec - infos.real_time.tv_sec) +
            (realTime.tv_usec - infos.real_time.tv_usec);
  usage = cpu_diff / (float)(real_diff);

  printf("%d\t%.3f\t%lu\t%lu\t%d\t%0x\t%s\n",
     id,usage,info.memory/1024,info.maxMem/1024,
    info.nrVirtCpu,info.state,virDomainGetName(dom));

freeDom(dom);
}

int main()
{
int idCount;
int i;
int id;
int ids[MAXID];
char *host;
unsigned long ver;

virNodeInfo nodeinfo;

TIMEINFONODE timeInfos[MAXID];

printf("----------------------------------------\n");
printf("      xen domain monitor vrsion 0.1     \n");
printf("      build by somebody.                \n");
printf("----------------------------------------\n");

/*connect to local xen hypervisor*/
conn = virConnectOpenReadOnly(NULL);
if(conn == NULL)
  {
   fprintf(stderr,"failed to connect to xen hypervisor\n");
   closeConn();
   return 0;
  }

host = virConnectGetHostname(conn);
printf("Hostname:%s\n",host);

printf("Virtualization type:%s\n",virConnectGetType(conn));
virConnectGetVersion(conn, &ver);
printf("Version:%lu\n",ver);

/*
virConnectGetLibVersion(conn, &ver);
printf("Libvirt Version:%lu\n",ver);
*/

virNodeGetInfo(conn, &nodeinfo);
printf("==========node info===============\n");
printf("Model:%s\n",nodeinfo.model);
printf("Memory:%lukb\n",nodeinfo.memory);
printf("Number of CPUs:%u\n",nodeinfo.cpus);
printf("MHz:%u\n",nodeinfo.mhz);
printf("Number of NUMA nodes:%u\n",nodeinfo.nodes);
printf("===============================\n");

   idCount = virConnectListDomains(conn,&ids[0],MAXID);
   if(idCount < 0)
   {
   fprintf(stderr,"failed to list domains\n");
   closeConn();
   return 0;
  }

  printf("Domain Totals: %d\n", idCount);
  printf("ID\tCPU\tMEM\tMaxMEM\tVCPUs\tState\tNAME\n");

     /* loop get the CPUtime info by IDs */
  for (i = 0; i < idCount; i++)
  {
   id = ids[i];
   getTimeInfo(id, &(timeInfos[i]));
  }

  sleep(1); //1 sec

  /* loop print the domain info and calculate the usage of cpus*/
  for (i = 0; i < idCount; i++)
  {
   id = ids[i];
   getDomainInfo(id, timeInfos[i]);

  }

  printf("--------------------------------------------------------\n");
  closeConn();

return 0;
}