vmstat.c

linux下获取一些环境信息的代码

// old: "Copyright 1994 by Henry Ware <[e-mail]>. Copyleft same year."
// most code copyright 2002 Albert Cahalan
// 
// 27/05/2003 (Fabian Frederick) : Add unit conversion + interface
//               	 Export proc/stat access to libproc
//			 Adapt vmstat helpfile
// 31/05/2003 (Fabian) : Add diskstat support (/libproc)
// June 2003 (Fabian) : -S <x> -s & -s -S <x> patch
// June 2003 (Fabian) : -Adding diskstat against 3.1.9, slabinfo
//			 -patching 'header' in disk & slab
// July 2003 (Fabian) : -Adding disk partition output
//			-Adding disk table
//			-Syncing help / usage

#include <stdio.h>
#include <stdlib.h>
#include <ctype.h>
#include <string.h>
#include <assert.h>
#include <fcntl.h>
#include <limits.h>
#include <termios.h>
#include <unistd.h>
#include <sys/types.h>
#include <sys/ioctl.h>
#include <sys/dir.h>
#include <dirent.h>

#include "proc/sysinfo.h"
#include "proc/version.h"

static unsigned long dataUnit=1024;
static char szDataUnit [16];
#define UNIT_B        1
#define UNIT_k        1000
#define UNIT_K        1024
#define UNIT_m        1000000
#define UNIT_M        1048576

#define VMSTAT        0
#define DISKSTAT      0x00000001
#define VMSUMSTAT     0x00000002
#define SLABSTAT      0x00000004
#define PARTITIONSTAT 0x00000008
#define DISKSUMSTAT   0x00000010

static int statMode=VMSTAT;

#define FALSE 0
#define TRUE 1

static int a_option; /* "-a" means "show active/inactive" */

static unsigned sleep_time = 1;
static unsigned long num_updates;

static unsigned int height;   // window height
static unsigned int moreheaders=TRUE;


/////////////////////////////////////////////////////////////////////////

static void usage(void) NORETURN;
static void usage(void) {
  fprintf(stderr,"usage: vmstat [-V] [-n] [delay [count]]\n");
  fprintf(stderr,"              -V prints version.\n");
  fprintf(stderr,"              -n causes the headers not to be reprinted regularly.\n");
  fprintf(stderr,"              -a print inactive/active page stats.\n");
  fprintf(stderr,"              -d prints disk statistics\n");
  fprintf(stderr,"              -D prints disk table\n");
  fprintf(stderr,"              -p prints disk partition statistics\n");
  fprintf(stderr,"              -s prints vm table\n");
  fprintf(stderr,"              -m prints slabinfo\n");
  fprintf(stderr,"              -S unit size\n");
  fprintf(stderr,"              delay is the delay between updates in seconds. \n");
  fprintf(stderr,"              unit size k:1000 K:1024 m:1000000 M:1048576 (default is K)\n");
  fprintf(stderr,"              count is the number of updates.\n");
  exit(EXIT_FAILURE);
}

/////////////////////////////////////////////////////////////////////////////

#if 0
// produce:  "  6  ", "123  ", "123k ", etc.
static int format_1024(unsigned long long val64, char *restrict dst){
  unsigned oldval;
  const char suffix[] = " kmgtpe";
  unsigned level = 0;
  unsigned val32;

  if(val64 < 1000){   // special case to avoid "6.0  " when plain "  6  " would do
    val32 = val64;
    return sprintf(dst,"%3u  ",val32);
  }

  while(val64 > 0xffffffffull){
    level++;
    val64 /= 1024;
  }

  val32 = val64;

  while(val32 > 999){
    level++;
    oldval = val32;
    val32 /= 1024;
  }

  if(val32 < 10){
    unsigned fract = (oldval % 1024) * 10 / 1024;
    return sprintf(dst, "%u.%u%c ", val32, fract, suffix[level]);
  }
  return sprintf(dst, "%3u%c ", val32, suffix[level]);
}


// produce:  "  6  ", "123  ", "123k ", etc.
static int format_1000(unsigned long long val64, char *restrict dst){
  unsigned oldval;
  const char suffix[] = " kmgtpe";
  unsigned level = 0;
  unsigned val32;

  if(val64 < 1000){   // special case to avoid "6.0  " when plain "  6  " would do
    val32 = val64;
    return sprintf(dst,"%3u  ",val32);
  }

  while(val64 > 0xffffffffull){
    level++;
    val64 /= 1000;
  }

  val32 = val64;

  while(val32 > 999){
    level++;
    oldval = val32;
    val32 /= 1000;
  }

  if(val32 < 10){
    unsigned fract = (oldval % 1000) / 100;
    return sprintf(dst, "%u.%u%c ", val32, fract, suffix[level]);
  }
  return sprintf(dst, "%3u%c ", val32, suffix[level]);
}
#endif

////////////////////////////////////////////////////////////////////////////

static void new_header(void){
  printf("procs -----------memory---------- ---swap-- -----io---- -system-- ----cpu----\n");
  printf(
    "%2s %2s %6s %6s %6s %6s %4s %4s %5s %5s %4s %4s %2s %2s %2s %2s\n",
    "r","b",
    "swpd", "free", a_option?"inact":"buff", a_option?"active":"cache",
    "si","so",
    "bi","bo",
    "in","cs",
    "us","sy","id","wa"
  );
}

////////////////////////////////////////////////////////////////////////////

static unsigned long unitConvert(unsigned int size){
 float cvSize;
 cvSize=(float)size/dataUnit*((statMode==SLABSTAT)?1:1024);
 return ((unsigned long) cvSize);
}

////////////////////////////////////////////////////////////////////////////

static void new_format(void) {
  const char format[]="%2u %2u %6lu %6lu %6lu %6lu %4u %4u %5u %5u %4u %4u %2u %2u %2u %2u\n";
  unsigned int tog=0; /* toggle switch for cleaner code */
  unsigned int i;
  unsigned int hz = Hertz;
  unsigned int running,blocked,dummy_1,dummy_2;
  jiff cpu_use[2], cpu_nic[2], cpu_sys[2], cpu_idl[2], cpu_iow[2], cpu_xxx[2], cpu_yyy[2], cpu_zzz[2];
  jiff duse, dsys, didl, diow, dstl, Div, divo2;
  unsigned long pgpgin[2], pgpgout[2], pswpin[2], pswpout[2];
  unsigned int intr[2], ctxt[2];
  unsigned int sleep_half; 
  unsigned long kb_per_page = sysconf(_SC_PAGESIZE) / 1024ul;
  int debt = 0;  // handle idle ticks running backwards

  sleep_half=(sleep_time/2);
  new_header();
  meminfo();

  getstat(cpu_use,cpu_nic,cpu_sys,cpu_idl,cpu_iow,cpu_xxx,cpu_yyy,cpu_zzz,
	  pgpgin,pgpgout,pswpin,pswpout,
	  intr,ctxt,
	  &running,&blocked,
	  &dummy_1, &dummy_2);

  duse= *cpu_use + *cpu_nic; 
  dsys= *cpu_sys + *cpu_xxx + *cpu_yyy;
  didl= *cpu_idl;
  diow= *cpu_iow;
  dstl= *cpu_zzz;
  Div= duse+dsys+didl+diow+dstl;
  divo2= Div/2UL;
  printf(format,
	 running, blocked,
	 unitConvert(kb_swap_used), unitConvert(kb_main_free),
	 unitConvert(a_option?kb_inactive:kb_main_buffers),
	 unitConvert(a_option?kb_active:kb_main_cached),
	 (unsigned)( (*pswpin  * unitConvert(kb_per_page) * hz + divo2) / Div ),
	 (unsigned)( (*pswpout * unitConvert(kb_per_page) * hz + divo2) / Div ),
	 (unsigned)( (*pgpgin                * hz + divo2) / Div ),
	 (unsigned)( (*pgpgout               * hz + divo2) / Div ),
	 (unsigned)( (*intr                  * hz + divo2) / Div ),
	 (unsigned)( (*ctxt                  * hz + divo2) / Div ),
	 (unsigned)( (100*duse                    + divo2) / Div ),
	 (unsigned)( (100*dsys                    + divo2) / Div ),
	 (unsigned)( (100*didl                    + divo2) / Div ),
	 (unsigned)( (100*diow                    + divo2) / Div ) /* ,
	 (unsigned)( (100*dstl                    + divo2) / Div ) */
  );

  for(i=1;i<num_updates;i++) { /* \\\\\\\\\\\\\\\\\\\\ main loop ////////////////// */
    sleep(sleep_time);
    if (moreheaders && ((i%height)==0)) new_header();
    tog= !tog;

    meminfo();

    getstat(cpu_use+tog,cpu_nic+tog,cpu_sys+tog,cpu_idl+tog,cpu_iow+tog,cpu_xxx+tog,cpu_yyy+tog,cpu_zzz+tog,
	  pgpgin+tog,pgpgout+tog,pswpin+tog,pswpout+tog,
	  intr+tog,ctxt+tog,
	  &running,&blocked,
	  &dummy_1,&dummy_2);

    duse= cpu_use[tog]-cpu_use[!tog] + cpu_nic[tog]-cpu_nic[!tog];
    dsys= cpu_sys[tog]-cpu_sys[!tog] + cpu_xxx[tog]-cpu_xxx[!tog] + cpu_yyy[tog]-cpu_yyy[!tog];
    didl= cpu_idl[tog]-cpu_idl[!tog];
    diow= cpu_iow[tog]-cpu_iow[!tog];
    dstl= cpu_zzz[tog]-cpu_zzz[!tog];

    /* idle can run backwards for a moment -- kernel "feature" */
    if(debt){
      didl = (int)didl + debt;
      debt = 0;
    }
    if( (int)didl < 0 ){
      debt = (int)didl;
      didl = 0;
    }

    Div= duse+dsys+didl+diow+dstl;
    divo2= Div/2UL;
    printf(format,
           running, blocked,
	   unitConvert(kb_swap_used),unitConvert(kb_main_free),
	   unitConvert(a_option?kb_inactive:kb_main_buffers),
	   unitConvert(a_option?kb_active:kb_main_cached),
	   (unsigned)( ( (pswpin [tog] - pswpin [!tog])*unitConvert(kb_per_page)+sleep_half )/sleep_time ), /*si*/
	   (unsigned)( ( (pswpout[tog] - pswpout[!tog])*unitConvert(kb_per_page)+sleep_half )/sleep_time ), /*so*/
	   (unsigned)( (  pgpgin [tog] - pgpgin [!tog]             +sleep_half )/sleep_time ), /*bi*/
	   (unsigned)( (  pgpgout[tog] - pgpgout[!tog]             +sleep_half )/sleep_time ), /*bo*/
	   (unsigned)( (  intr   [tog] - intr   [!tog]             +sleep_half )/sleep_time ), /*in*/
	   (unsigned)( (  ctxt   [tog] - ctxt   [!tog]             +sleep_half )/sleep_time ), /*cs*/
	   (unsigned)( (100*duse+divo2)/Div ), /*us*/
	   (unsigned)( (100*dsys+divo2)/Div ), /*sy*/
	   (unsigned)( (100*didl+divo2)/Div ), /*id*/
	   (unsigned)( (100*diow+divo2)/Div )/*, //wa
	   (unsigned)( (100*dstl+divo2)/Div )  //st  */
    );
  }
}

////////////////////////////////////////////////////////////////////////////

static void diskpartition_header(const char *partition_name){
  printf("%-10s %10s %10s %10s %10s\n",partition_name, "reads  ", "read sectors", "writes   ", "requested writes");
}

////////////////////////////////////////////////////////////////////////////

static int diskpartition_format(const char* partition_name){
    FILE *fDiskstat;
    struct disk_stat *disks;
    struct partition_stat *partitions, *current_partition=NULL;
    unsigned long ndisks, j, k, npartitions;
    const char format[] = "%20u %10llu %10u %10u\n";

    fDiskstat=fopen("/proc/diskstats","rb");
    if(!fDiskstat){
        fprintf(stderr, "Your kernel doesn't support diskstat. (2.5.70 or above required)\n"); 
        exit(0);
    }

    fclose(fDiskstat);
    ndisks=getdiskstat(&disks,&partitions);
    npartitions=getpartitions_num(disks, ndisks);
    for(k=0; k<npartitions; k++){
       if(!strcmp(partition_name, partitions[k].partition_name)){
                current_partition=&(partitions[k]); 
       }	
    }
    if(!current_partition){
         return -1;
    }
    diskpartition_header(partition_name);
    printf (format,
       current_partition->reads,current_partition->reads_sectors,current_partition->writes,current_partition->requested_writes);
    fflush(stdout);
    free(disks);
    free(partitions);
    for(j=1; j<num_updates; j++){ 
        if (moreheaders && ((j%height)==0)) diskpartition_header(partition_name);
        sleep(sleep_time);
        ndisks=getdiskstat(&disks,&partitions);
        npartitions=getpartitions_num(disks, ndisks);
	current_partition=NULL;
        for(k=0; k<npartitions; k++){
          if(!strcmp(partition_name, partitions[k].partition_name)){
                  current_partition=&(partitions[k]); 
          }	
        }
        if(!current_partition){
           return -1;
        }
        printf (format,
        current_partition->reads,current_partition->reads_sectors,current_partition->writes,current_partition->requested_writes);
        fflush(stdout);
        free(disks);
        free(partitions);
    }
    return 0;
}

////////////////////////////////////////////////////////////////////////////

static void diskheader(void){
  printf("disk- ------------reads------------ ------------writes----------- -----IO------\n");

  printf("%5s %6s %6s %7s %7s %6s %6s %7s %7s %6s %6s\n",
         " ", "total", "merged","sectors","ms","total","merged","sectors","ms","cur","sec");

}