util_funcs.c

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//==========================================================================
//
//      ./agent/current/src/mibgroup/util_funcs.c
//
//
//==========================================================================
//####ECOSGPLCOPYRIGHTBEGIN####
// -------------------------------------------
// This file is part of eCos, the Embedded Configurable Operating System.
// Copyright (C) 1998, 1999, 2000, 2001, 2002 Red Hat, Inc.
//
// eCos is free software; you can redistribute it and/or modify it under
// the terms of the GNU General Public License as published by the Free
// Software Foundation; either version 2 or (at your option) any later version.
//
// eCos is distributed in the hope that it will be useful, but WITHOUT ANY
// WARRANTY; without even the implied warranty of MERCHANTABILITY or
// FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
// for more details.
//
// You should have received a copy of the GNU General Public License along
// with eCos; if not, write to the Free Software Foundation, Inc.,
// 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA.
//
// As a special exception, if other files instantiate templates or use macros
// or inline functions from this file, or you compile this file and link it
// with other works to produce a work based on this file, this file does not
// by itself cause the resulting work to be covered by the GNU General Public
// License. However the source code for this file must still be made available
// in accordance with section (3) of the GNU General Public License.
//
// This exception does not invalidate any other reasons why a work based on
// this file might be covered by the GNU General Public License.
//
// Alternative licenses for eCos may be arranged by contacting Red Hat, Inc.
// at http://sources.redhat.com/ecos/ecos-license/
// -------------------------------------------
//####ECOSGPLCOPYRIGHTEND####
//####UCDSNMPCOPYRIGHTBEGIN####
//
// -------------------------------------------
//
// Portions of this software may have been derived from the UCD-SNMP
// project,  <http://ucd-snmp.ucdavis.edu/>  from the University of
// California at Davis, which was originally based on the Carnegie Mellon
// University SNMP implementation.  Portions of this software are therefore
// covered by the appropriate copyright disclaimers included herein.
//
// The release used was version 4.1.2 of May 2000.  "ucd-snmp-4.1.2"
// -------------------------------------------
//
//####UCDSNMPCOPYRIGHTEND####
//==========================================================================
//#####DESCRIPTIONBEGIN####
//
// Author(s):    hmt
// Contributors: hmt
// Date:         2000-05-30
// Purpose:      Port of UCD-SNMP distribution to eCos.
// Description:  
//              
//
//####DESCRIPTIONEND####
//
//==========================================================================
/********************************************************************
       Copyright 1989, 1991, 1992 by Carnegie Mellon University

			  Derivative Work -
Copyright 1996, 1998, 1999, 2000 The Regents of the University of California

			 All Rights Reserved

Permission to use, copy, modify and distribute this software and its
documentation for any purpose and without fee is hereby granted,
provided that the above copyright notice appears in all copies and
that both that copyright notice and this permission notice appear in
supporting documentation, and that the name of CMU and The Regents of
the University of California not be used in advertising or publicity
pertaining to distribution of the software without specific written
permission.

CMU AND THE REGENTS OF THE UNIVERSITY OF CALIFORNIA DISCLAIM ALL
WARRANTIES WITH REGARD TO THIS SOFTWARE, INCLUDING ALL IMPLIED
WARRANTIES OF MERCHANTABILITY AND FITNESS.  IN NO EVENT SHALL CMU OR
THE REGENTS OF THE UNIVERSITY OF CALIFORNIA BE LIABLE FOR ANY SPECIAL,
INDIRECT OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING
FROM THE LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION OF
CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN
CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
*********************************************************************/
/*
 * util_funcs.c
 */

#include <config.h>

#if HAVE_IO_H
#include <io.h>
#endif
#include <stdio.h>
#if HAVE_STDLIB_H
#include <stdlib.h>
#endif
#if HAVE_MALLOC_H
#include <malloc.h>
#endif
#include <sys/types.h>
#ifdef __alpha
#ifndef _BSD
#define _BSD
#define _myBSD
#endif
#endif
#if HAVE_SYS_WAIT_H
# include <sys/wait.h>
#endif
#ifdef __alpha
#ifdef _myBSD
#undef _BSD
#undef _myBSD
#endif
#endif
#ifndef WEXITSTATUS
# define WEXITSTATUS(stat_val) ((unsigned)(stat_val) >> 8)
#endif
#ifndef WIFEXITED
# define WIFEXITED(stat_val) (((stat_val) & 255) == 0)
#endif
#if TIME_WITH_SYS_TIME
# ifdef WIN32
#  include <sys/timeb.h>
# else
#  include <sys/time.h>
# endif
# include <time.h>
#else
# if HAVE_SYS_TIME_H
#  include <sys/time.h>
# else
#  include <time.h>
# endif
#endif
#if HAVE_UNISTD_H
#include <unistd.h>
#endif
#if HAVE_FCNTL_H
#include <fcntl.h>
#endif
#include <errno.h>
#include <signal.h>
#if HAVE_STRING_H
#include <string.h>
#else
#include <strings.h>
#endif
#include <ctype.h>
#if HAVE_WINSOCK_H
#include <winsock.h>
#endif
#if HAVE_BASETSD_H
#include <basetsd.h>
#define ssize_t SSIZE_T
#endif
#if HAVE_RAISE
#define alarm raise
#endif
#include "mibincl.h"
#include "mibgroup/struct.h"
#include "mibgroup/util_funcs.h"
#include "system.h"
#if HAVE_LIMITS_H
#include "limits.h"
#endif
#ifdef USING_UCD_SNMP_ERRORMIB_MODULE
#include "ucd-snmp/errormib.h"
#else
#define setPerrorstatus(x) snmp_log_perror(x)
#endif
#include "read_config.h"

#ifdef EXCACHETIME
static long cachetime;
#endif

extern int numprocs, numextens;

void
Exit(int var)
{
  snmp_log(LOG_ERR, "Server Exiting with code %d\n",var);
  exit(var);
}

int shell_command(struct extensible *ex)
{
#if HAVE_SYSTEM
  char shellline[STRMAX];
  FILE *shellout;
  
  sprintf(shellline,"%s > /tmp/shoutput",ex->command);
  ex->result = system(shellline);
  ex->result = WEXITSTATUS(ex->result);
  shellout = fopen("/tmp/shoutput","r");
  if((shellout = fopen("/tmp/shoutput","r")) != NULL) {
    if (fgets(ex->output,STRMAX,shellout) == NULL) {
      ex->output[0] = 0;
    }
    fclose(shellout);
  }
  unlink("/tmp/shoutput");
#else
  ex->output[0] = 0;
  ex->result = 0;
#endif
  return(ex->result);
}

#define MAXOUTPUT 300

int exec_command(struct extensible *ex)
{
#if HAVE_EXECV
  int fd;
  FILE *file;
  
  if ((fd = get_exec_output(ex))) {
    file = fdopen(fd,"r");
    if (fgets(ex->output,STRMAX,file) == NULL) {
      ex->output[0] = 0;
    }
    fclose(file);
    wait_on_exec(ex);
  } else
#endif
  {
    ex->output[0] = 0;
    ex->result = 0;
  }
  return(ex->result);
}

void wait_on_exec(struct extensible *ex)
{
#ifndef __ECOS
#ifndef EXCACHETIME
    if (ex->pid && waitpid(ex->pid,&ex->result,0) < 0) {
      setPerrorstatus("waitpid");
    }
    ex->pid = 0;
#endif
#endif
}

#define MAXARGS 30

int get_exec_output(struct extensible *ex)
{
#if HAVE_EXECV
  int fd[2],i, cnt;
  char ctmp[STRMAX], *cptr1, *cptr2, argvs[STRMAX], **argv, **aptr;
#ifdef EXCACHETIME
  char cache[MAXCACHESIZE];
  ssize_t cachebytes;
  long curtime;
  static char lastcmd[STRMAX];
  int cfd;
  static int lastresult;
  int readcount;
#endif

#ifdef EXCACHETIME
  curtime = time(NULL);
  if (curtime > (cachetime + EXCACHETIME) ||
      strcmp(ex->command, lastcmd) != 0) {
    strcpy(lastcmd,ex->command);
    cachetime = curtime;
#endif
    if (pipe(fd)) 
      {
        setPerrorstatus("pipe");
#ifdef EXCACHETIME
        cachetime = 0;
#endif
        return 0;
      }
    if ((ex->pid = fork()) == 0) 
      {
        close(1);
        if (dup(fd[1]) != 1)
          {
            setPerrorstatus("dup");
            return 0;
          }
        close(fd[1]);
        close(fd[0]);
        for(cnt=1,cptr1 = ex->command, cptr2 = argvs; *cptr1 != 0;
            cptr2++, cptr1++) {
          *cptr2 = *cptr1;
          if (*cptr1 == ' ') {
            *(cptr2++) = 0;
            cptr1 = skip_white(cptr1);
            *cptr2 = *cptr1;
            if (*cptr1 != 0) cnt++;
          }
        }
        *cptr2 = 0;
        *(cptr2+1) = 0;
        argv = (char **) malloc((cnt+2) * sizeof(char *));
        if (argv == NULL)
          return 0; /* memory alloc error */
        aptr = argv;
        *(aptr++) = argvs;
        for (cptr2 = argvs, i=1; i != cnt; cptr2++)
          if (*cptr2 == 0) {
            *(aptr++) = cptr2 + 1;
            i++;
          }
        while (*cptr2 != 0) cptr2++;
        *(aptr++) = NULL;
        copy_word(ex->command,ctmp);
        execv(ctmp,argv);
        snmp_log_perror(ctmp);
        exit(1);
      }
    else
      {
        close(fd[1]);
        if (ex->pid < 0) {
          close(fd[0]);
          setPerrorstatus("fork");
#ifdef EXCACHETIME
          cachetime = 0;
#endif
          return 0;
        }
#ifdef EXCACHETIME
        unlink(CACHEFILE);
	/* XXX  Use SNMP_FILEMODE_CLOSED instead of 644? */
        if ((cfd = open(CACHEFILE,O_WRONLY|O_TRUNC|O_CREAT,0644)) < 0) {
          setPerrorstatus("open");
          cachetime = 0;
          return 0;
        }
        fcntl(fd[0],F_SETFL,O_NONBLOCK);  /* don't block on reads */
#ifdef HAVE_USLEEP
        for (readcount = 0; readcount <= MAXREADCOUNT*100 &&
               (cachebytes = read(fd[0],(void *)cache,MAXCACHESIZE));
             readcount++) {
#else
        for (readcount = 0; readcount <= MAXREADCOUNT &&
               (cachebytes = read(fd[0],(void *)cache,MAXCACHESIZE));
             readcount++) {
#endif
          if (cachebytes > 0)
            write(cfd,(void *) cache, cachebytes);
          else if (cachebytes == -1 && errno != EAGAIN) {
            setPerrorstatus("read");
            break;
          }
          else
#ifdef HAVE_USLEEP
            usleep (10000);	/* sleeps for 0.01 sec */
#else
	    sleep (1);
#endif
        }
        close(cfd);
        close(fd[0]);
        /* wait for the child to finish */
        if (ex->pid > 0 && waitpid(ex->pid,&ex->result,0) < 0) {
          setPerrorstatus("waitpid()");
          cachetime = 0;
          return 0;
        }
        ex->pid = 0;
        ex->result = WEXITSTATUS(ex->result);
        lastresult = ex->result;
#else /* !EXCACHETIME */
        return(fd[0]);
#endif
      }
#ifdef EXCACHETIME
  }
  else {
      ex->result = lastresult;
  }
  if ((cfd = open(CACHEFILE,O_RDONLY)) < 0) {
    setPerrorstatus("open");
    return 0;
  }
  return(cfd);
#endif

#else /* !HAVE_EXECV */
  return 0;