vmstat_linux.c

开发snmp的开发包有两个开放的SNMP开发库

#include <net-snmp/net-snmp-config.h>

#if HAVE_LIMITS_H
#include <limits.h>
#endif
#if HAVE_STDLIB_H
#include <stdlib.h>
#endif
#if HAVE_UNISTD_H
#include <unistd.h>
#endif
#if HAVE_FCNTL_H
#include <fcntl.h>
#endif
#include <ctype.h>
#include <signal.h>
#if HAVE_MACHINE_PARAM_H
#include <machine/param.h>
#endif
#if HAVE_SYS_VMMETER_H
#if !defined(bsdi2) && !defined(netbsd1)
#include <sys/vmmeter.h>
#endif
#endif
#if HAVE_SYS_CONF_H
#include <sys/conf.h>
#endif
#if HAVE_SYS_FS_H
#include <sys/fs.h>
#else
#if HAVE_UFS_FS_H
#include <ufs/fs.h>
#else
#ifdef HAVE_SYS_STAT_H
#include <sys/stat.h>
#endif
#ifdef HAVE_SYS_VNODE_H
#include <sys/vnode.h>
#endif
#ifdef HAVE_UFS_UFS_QUOTA_H
#include <ufs/ufs/quota.h>
#endif
#ifdef HAVE_UFS_UFS_INODE_H
#include <ufs/ufs/inode.h>
#endif
#if HAVE_UFS_FFS_FS_H
#include <ufs/ffs/fs.h>
#endif
#endif
#endif
#if HAVE_MTAB_H
#include <mtab.h>
#endif
#include <sys/stat.h>
#include <errno.h>
#if HAVE_FSTAB_H
#include <fstab.h>
#endif
#if HAVE_SYS_STATVFS_H
#include <sys/statvfs.h>
#endif
#if HAVE_SYS_VFS_H
#include <sys/vfs.h>
#endif
#if (!defined(HAVE_STATVFS)) && defined(HAVE_STATFS)
#if HAVE_SYS_PARAM_H
#include <sys/param.h>
#endif
#if HAVE_SYS_MOUNT_H
#include <sys/mount.h>
#endif
#if HAVE_SYS_SYSCTL_H
#include <sys/sysctl.h>
#endif
#define statvfs statfs
#endif
#if HAVE_VM_SWAP_PAGER_H
#include <vm/swap_pager.h>
#endif
#if HAVE_SYS_FIXPOINT_H
#include <sys/fixpoint.h>
#endif
#if HAVE_MALLOC_H
#include <malloc.h>
#endif
#if HAVE_STRING_H
#include <string.h>
#else
#include <strings.h>
#endif
#if TIME_WITH_SYS_TIME
# include <sys/time.h>
# include <time.h>
#else
# if HAVE_SYS_TIME_H
#  include <sys/time.h>
# else
#  include <time.h>
# endif
#endif

#include <sys/utsname.h>

#include <net-snmp/net-snmp-includes.h>
#include <net-snmp/agent/net-snmp-agent-includes.h>
#include <net-snmp/agent/auto_nlist.h>
#include <net-snmp/agent/hardware/cpu.h>

#include "mibdefs.h"
#include "struct.h"
#include "util_funcs.h"
#include "vmstat.h"

FindVarMethod var_extensible_vmstat;

static int has_vmstat = 1;
static int has_cpu_26 = 1;
static time_t cache_time;
#define CACHE_TIMEOUT	5

#define STAT_FILE	"/proc/stat"
#define VMSTAT_FILE	"/proc/vmstat"


void
init_vmstat(void)
{
    struct variable2 extensible_vmstat_variables[] = {
        {MIBINDEX, ASN_INTEGER, RONLY, var_extensible_vmstat, 1,
         {MIBINDEX}},
        {ERRORNAME, ASN_OCTET_STR, RONLY, var_extensible_vmstat, 1,
         {ERRORNAME}},
        {SWAPIN, ASN_INTEGER, RONLY, var_extensible_vmstat, 1, {SWAPIN}},
        {SWAPOUT, ASN_INTEGER, RONLY, var_extensible_vmstat, 1, {SWAPOUT}},
        {RAWSWAPIN, ASN_COUNTER, RONLY, var_extensible_vmstat, 1, {RAWSWAPIN}},
        {RAWSWAPOUT, ASN_COUNTER, RONLY, var_extensible_vmstat, 1, {RAWSWAPOUT}},
        {IOSENT, ASN_INTEGER, RONLY, var_extensible_vmstat, 1, {IOSENT}},
        {IORECEIVE, ASN_INTEGER, RONLY, var_extensible_vmstat, 1,
         {IORECEIVE}},
        {IORAWSENT, ASN_COUNTER, RONLY, var_extensible_vmstat, 1, {IORAWSENT}},
        {IORAWRECEIVE, ASN_COUNTER, RONLY, var_extensible_vmstat, 1,
         {IORAWRECEIVE}},
        {SYSINTERRUPTS, ASN_INTEGER, RONLY, var_extensible_vmstat, 1,
         {SYSINTERRUPTS}},
        {SYSCONTEXT, ASN_INTEGER, RONLY, var_extensible_vmstat, 1,
         {SYSCONTEXT}},
        {CPUUSER, ASN_INTEGER, RONLY, var_extensible_vmstat, 1, {CPUUSER}},
        {CPUSYSTEM, ASN_INTEGER, RONLY, var_extensible_vmstat, 1,
         {CPUSYSTEM}},
        {CPUIDLE, ASN_INTEGER, RONLY, var_extensible_vmstat, 1, {CPUIDLE}},
        {CPURAWUSER, ASN_COUNTER, RONLY, var_extensible_vmstat, 1,
         {CPURAWUSER}},
        {CPURAWNICE, ASN_COUNTER, RONLY, var_extensible_vmstat, 1,
         {CPURAWNICE}},
        {CPURAWSYSTEM, ASN_COUNTER, RONLY, var_extensible_vmstat, 1,
         {CPURAWSYSTEM}},
        {CPURAWKERNEL, ASN_COUNTER, RONLY, var_extensible_vmstat, 1,
         {CPURAWKERNEL}},
        {CPURAWIDLE, ASN_COUNTER, RONLY, var_extensible_vmstat, 1,
         {CPURAWIDLE}},
        {SYSRAWINTERRUPTS, ASN_COUNTER, RONLY, var_extensible_vmstat, 1,
         {SYSRAWINTERRUPTS}},
        {SYSRAWCONTEXT, ASN_COUNTER, RONLY, var_extensible_vmstat, 1,
         {SYSRAWCONTEXT}},
        {CPURAWWAIT, ASN_COUNTER, RONLY, var_extensible_vmstat, 1,
         {CPURAWWAIT}},
        {CPURAWINTR, ASN_COUNTER, RONLY, var_extensible_vmstat, 1,
         {CPURAWINTR}},
        {CPURAWSOFTIRQ, ASN_COUNTER, RONLY, var_extensible_vmstat, 1,
         {CPURAWSOFTIRQ}},
        /*
         * Future use: 
         */
        /*
         * {ERRORFLAG, ASN_INTEGER, RONLY, var_extensible_vmstat, 1, {ERRORFLAG }},
         * {ERRORMSG, ASN_OCTET_STR, RONLY, var_extensible_vmstat, 1, {ERRORMSG }}
         */
    };

    /*
     * Define the OID pointer to the top of the mib tree that we're
     * registering underneath 
     */
    oid             vmstat_variables_oid[] = { NETSNMP_UCDAVIS_MIB, 11 };

    /*
     * register ourselves with the agent to handle our mib tree 
     */
    REGISTER_MIB("ucd-snmp/vmstat", extensible_vmstat_variables, variable2,
                 vmstat_variables_oid);
}


static void
getstat(unsigned long *cuse, unsigned long *cice, unsigned long *csys,
        unsigned long *cide, unsigned *pin, unsigned *pout,
        unsigned *swpin, unsigned *swpout, unsigned *itot, unsigned *i1,
        unsigned *ct, unsigned long *ciow, unsigned long *cirq,
	unsigned long *csoft)
{
    int             statfd, vmstatfd;
    static int      first = 1;
    static char    *buff = NULL, *vmbuff = NULL;
    static int      bsize = 0, vmbsize = 0;
    char           *b, *c;
    time_t          now;
    unsigned long long cpunum;
    unsigned long long cusell = 0, cicell = 0, csysll = 0, cidell = 0,
        ciowll = 0, cirqll = 0, csoftll = 0, ctll = 0, itotll = 0, i1ll = 0;

    time(&now);
    if (cache_time + CACHE_TIMEOUT < now) {
	if ((statfd = open(STAT_FILE, O_RDONLY, 0)) == -1) {
	    snmp_log_perror(STAT_FILE);
	    return;
	}
        if (bsize == 0) {
            bsize = 256;
            buff = malloc(bsize);
        }
        while (read(statfd, buff, bsize) == bsize) {
            bsize += 256;
            buff = realloc(buff, bsize);
            DEBUGMSGTL(("vmstat", "/proc/stat buffer increased to %d\n", bsize));
            close(statfd);
            statfd = open(STAT_FILE, O_RDONLY, 0);
        }
        close(statfd);
	if (has_vmstat && (vmstatfd = open(VMSTAT_FILE, O_RDONLY, 0)) != -1) {
	    if (vmbsize == 0) {
		vmbsize = 256;
		vmbuff = malloc(vmbsize);
	    }
	    while (read(vmstatfd, vmbuff, vmbsize) == vmbsize) {
		vmbsize += 256;
		vmbuff = realloc(vmbuff, vmbsize);
		close(vmstatfd);
		vmstatfd = open(VMSTAT_FILE, O_RDONLY, 0);
	    }
	    close(vmstatfd);
	}
	else
	    has_vmstat = 0;
	cache_time = now;
    }

    *itot = 0;
    *i1 = 1;
    c = buff;
    while ((c = strstr(c+1, "cpu")) != NULL)
        b = c;
    sscanf(b, "cpu%llu", &cpunum);
    cpunum++;
    b = strstr(buff, "cpu ");
    if (b) {
	if (!has_cpu_26 ||
            sscanf(b, "cpu  %llu %llu %llu %llu %llu %llu %llu", &cusell,
                   &cicell, &csysll, &cidell, &ciowll, &cirqll, &csoftll) != 7) {
	    has_cpu_26 = 0;
	    sscanf(b, "cpu  %llu %llu %llu %llu", &cusell, &cicell, &csysll,
                   &cidell);
	    *ciow = *cirq = *csoft = 0;
	} else {
  	    *ciow = (unsigned long)(ciowll/cpunum);
  	    *cirq = (unsigned long)(cirqll/cpunum);
  	    *csoft = (unsigned long)(csoftll/cpunum);
 	}
	*cuse = (unsigned long)(cusell/cpunum);
	*cice = (unsigned long)(cicell/cpunum);
	*csys = (unsigned long)(csysll/cpunum);
	*cide = (unsigned long)(cidell/cpunum);

    }
    else {
	if (first)
	    snmp_log(LOG_ERR, "No cpu line in %s\n", STAT_FILE);
	*cuse = *cice = *csys = *cide = *ciow = *cirq = *csoft = 0;
    }
    if (has_vmstat) {
	b = strstr(vmbuff, "pgpgin ");
	if (b)