//==========================================================================
//
//      ./lib/current/src/read_config.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.
*********************************************************************/
/*
 * read_config.c
 */

#include <config.h>

#include <stdio.h>
#include <ctype.h>
#if HAVE_STDLIB_H
#include <stdlib.h>
#endif
#if HAVE_STRING_H
#include <string.h>
#else
#include <strings.h>
#endif
#if HAVE_UNISTD_H
#include <unistd.h>
#endif
#include <sys/types.h>
#if HAVE_SYS_PARAM_H
#include <sys/param.h>
#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
#ifdef HAVE_SYS_STAT_H
#include <sys/stat.h>
#endif
#if HAVE_NETINET_IN_H
#include <netinet/in.h>
#endif
#if HAVE_ARPA_INET_H
#include <arpa/inet.h>
#endif
#if HAVE_SYS_SELECT_H
#include <sys/select.h>
#endif
#if HAVE_WINSOCK_H
#include <winsock.h>
#endif
#if HAVE_SYS_SOCKET_H
#include <sys/socket.h>
#endif
#if HAVE_NETDB_H
#include <netdb.h>
#endif
#include <errno.h>

#if HAVE_DMALLOC_H
#include <dmalloc.h>
#endif

#include "asn1.h"
#include "mib.h"
#include "parse.h"
#include "system.h"
#include "snmp_api.h"
#include "snmp_debug.h"
#include "snmp_logging.h"
#include "snmp_impl.h"
#include "default_store.h"
#include "callback.h"

#include "read_config.h"
#include "tools.h"

int config_errors;

struct config_files *config_files = NULL;

struct config_line *
register_premib_handler(const char *type,
			const char *token,
			void (*parser) (const char *, char *),
			void (*releaser) (void),
			const char *help)
{
  struct config_line *ltmp;
  ltmp = register_config_handler(type, token, parser, releaser, help);
  if (ltmp != NULL)
    ltmp->config_time = PREMIB_CONFIG;
  return (ltmp);
}

struct config_line *
register_app_premib_handler(const char *token,
			void (*parser) (const char *, char *),
			void (*releaser) (void),
			const char *help)
{
  return(register_premib_handler( NULL, token, parser, releaser, help ));
}

/*******************************************************************-o-******
 * register_config_handler
 *
 * Parameters:
 *	*type
 *	*token
 *	*parser
 *	*releaser
 *      
 * Returns:
 *	Pointer to a new config line entry  -OR-  NULL on error.
 */
struct config_line *
register_config_handler(const char *type_param,
			const char *token,
			void (*parser) (const char *, char *),
			void (*releaser) (void),
			const char *help)
{
  struct config_files **ctmp = &config_files;
  struct config_line **ltmp;
  const char *type = type_param;

  if ( type == NULL )
    type = ds_get_string(DS_LIBRARY_ID, DS_LIB_APPTYPE);

  /* 
   * Find type in current list  -OR-  create a new file type.
   */
  while (*ctmp != NULL && strcmp((*ctmp)->fileHeader, type)) {
    ctmp = &((*ctmp)->next);
  }

  if (*ctmp == NULL) {
    *ctmp = (struct config_files *)
      malloc(sizeof(struct config_files));
    if ( !*ctmp ) {
      return NULL;
    }

    (*ctmp)->next		 = NULL;
    (*ctmp)->start		 = NULL;
    (*ctmp)->fileHeader	 = strdup(type);
  }

  /* 
   * Find parser type in current list  -OR-  create a new
   * line parser entry.
   */
  ltmp = &((*ctmp)->start);

  while (*ltmp != NULL && strcmp((*ltmp)->config_token, token)) {
    ltmp = &((*ltmp)->next);
  }

  if (*ltmp == NULL) {
    *ltmp = (struct config_line *)
      malloc(sizeof(struct config_line));
    if ( !*ltmp ) {
      return NULL;
    }

    (*ltmp)->next		 = NULL;
    (*ltmp)->config_time	 = NORMAL_CONFIG;
    (*ltmp)->parse_line	 = 0;
    (*ltmp)->free_func	 = 0;
    (*ltmp)->config_token	 = strdup(token);
    if (help != NULL)
      (*ltmp)->help = strdup(help);

  }

  /* 
   * Add/Replace the parse/free functions for the given line type
   * in the given file type.
   */
  (*ltmp)->parse_line = parser;
  (*ltmp)->free_func  = releaser;

  return (*ltmp);

}  /* end register_config_handler() */

struct config_line *
register_app_config_handler(const char *token,
			void (*parser) (const char *, char *),
			void (*releaser) (void),
			const char *help)
{
  return(register_config_handler( NULL, token, parser, releaser, help ));
}

void
unregister_config_handler(const char *type_param, 
			  const char *token)
{
  struct config_files **ctmp = &config_files;
  struct config_line **ltmp, *ltmp2;
  const char *type = type_param;

  if ( type == NULL )
    type = ds_get_string(DS_LIBRARY_ID, DS_LIB_APPTYPE);

  /* find type in current list */
  while (*ctmp != NULL && strcmp((*ctmp)->fileHeader,type)) {
    ctmp = &((*ctmp)->next);
  }

  if (*ctmp == NULL) {
    /* Not found, return. */
    return;
  }
  
  ltmp = &((*ctmp)->start);
  if (*ltmp == NULL) {
    /* Not found, return. */
    return;
  }
  if (strcmp((*ltmp)->config_token,token) == 0) {
    /* found it at the top of the list */
    (*ctmp)->start = (*ltmp)->next;
    free((*ltmp)->config_token);
    SNMP_FREE((*ltmp)->help);
    free(*ltmp);
    return;
  }
  while ((*ltmp)->next != NULL && strcmp((*ltmp)->next->config_token,token)) {
    ltmp = &((*ltmp)->next);
  }
  if (*ltmp == NULL) {
    free((*ltmp)->config_token);
    SNMP_FREE((*ltmp)->help);
    ltmp2 = (*ltmp)->next->next;
    free((*ltmp)->next);
    (*ltmp)->next = ltmp2;
  }
}

void
unregister_app_config_handler(const char *token)
{
  unregister_config_handler( NULL, token );
}

#ifdef TESTING
void print_config_handlers (void)
{
  struct config_files *ctmp = config_files;
  struct config_line *ltmp;

  for(;ctmp != NULL; ctmp = ctmp->next) {
    DEBUGMSGTL(("read_config", "read_conf: %s\n", ctmp->fileHeader));
    for(ltmp = ctmp->start; ltmp != NULL; ltmp = ltmp->next)
      DEBUGMSGTL(("read_config", "                   %s\n", ltmp->config_token));
  }
}
#endif

int linecount;
const char *curfilename;

void read_config_with_type(const char *filename, 
			   const char *type)
{
  struct config_files *ctmp = config_files;
  for(;ctmp != NULL && strcmp(ctmp->fileHeader,type); ctmp = ctmp->next);
  if (ctmp)
    read_config(filename, ctmp->start, EITHER_CONFIG);
  else
    DEBUGMSGTL(("read_config", "read_config: I have no registrations for type:%s,file:%s\n",
           type, filename));
}

/*******************************************************************-o-******
 * read_config
 *
 * Parameters:
 *	*filename
 *	*line_handler
 *	 when
 *
 * Read <filename> and process each line in accordance with the list of
 * <line_handler> functions.
 *
 *
 * For each line in <filename>, search the list of <line_handler>'s 
 * for an entry that matches the first token on the line.  This comparison is
 * case insensitive.
 *
 * For each match, check that <when> is the designated time for the
 * <line_handler> function to be executed before processing the line.
 */
void read_config(const char *filename,
		 struct config_line *line_handler,
		 int when)
{

  FILE *ifile;
  char line[STRINGMAX], token[STRINGMAX], tmpbuf[STRINGMAX];
  char *cptr;
  int i, done;
  struct config_line *lptr;

  linecount = 0;
  curfilename = filename;
  
  if ((ifile = fopen(filename, "r")) == NULL) {
#ifdef ENOENT
    if (errno == ENOENT) {
      DEBUGMSGTL(("read_config", "%s: %s\n", filename, strerror(errno)));
    } else
#endif /* ENOENT */
#ifdef EACCES
    if (errno == EACCES) {
      DEBUGMSGTL(("read_config", "%s: %s\n", filename, strerror(errno)));
    } else
#endif /* EACCES */
#if defined(ENOENT) || defined(EACCES)
    {
      snmp_log_perror(filename);
    }
#else /* defined(ENOENT) || defined(EACCES) */
    snmp_log_perror(filename);
#endif /* ENOENT */
    return;
  } else {
    DEBUGMSGTL(("read_config", "Reading configuration %s\n", filename));
  }

  while (fgets(line, sizeof(line), ifile) != NULL) 
    {
      lptr = line_handler;
      linecount++;
      cptr = line;
      i = strlen(line)-1;
      if (line[i] == '\n')
        line[i] = 0;
      /* check blank line or # comment */
      if ((cptr = skip_white(cptr)))
	{
          cptr = copy_word(cptr,token);
          if (cptr == NULL) {
            sprintf(tmpbuf,"Blank line following %s token.", token);
            config_perror(tmpbuf);
          } else {
            for(lptr = line_handler, done=0;
                lptr != NULL && !done;
                lptr = lptr->next) {
              if (!strcasecmp(token,lptr->config_token)) {
                if (when == EITHER_CONFIG || lptr->config_time == when) {
                    DEBUGMSGTL(("read_config", "%s:%d Parsing: %s\n",
                                filename, linecount, line));
                    (*(lptr->parse_line))(token,cptr);
                }
                done = 1;
              }
            }
            if (!done && when != PREMIB_CONFIG &&
                !ds_get_boolean(DS_LIBRARY_ID, DS_LIB_NO_TOKEN_WARNINGS)) {
              sprintf(tmpbuf,"Unknown token: %s.", token);
              config_pwarn(tmpbuf);
            }
          }
	}
    }
  fclose(ifile);
  return;

}  /* end read_config() */



void
free_config (void)
{
  struct config_files *ctmp = config_files;
  struct config_line *ltmp;

  for(;ctmp != NULL; ctmp = ctmp->next)
    for(ltmp = ctmp->start; ltmp != NULL; ltmp = ltmp->next)
      if (ltmp->free_func)
        (*(ltmp->free_func))();
}

void
read_configs (void)
{

  char *optional_config = ds_get_string(DS_LIBRARY_ID, DS_LIB_OPTIONALCONFIG);
  char *type = ds_get_string(DS_LIBRARY_ID, DS_LIB_APPTYPE);

  DEBUGMSGTL(("read_config","reading normal configuration tokens\n"));
  
  if (!ds_get_boolean(DS_LIBRARY_ID, DS_LIB_DONT_READ_CONFIGS))
    read_config_files(NORMAL_CONFIG);

 /* do this even when the normal above wasn't done */
  if (optional_config && type)
    read_config_with_type(optional_config, type);

  snmp_call_callbacks(SNMP_CALLBACK_LIBRARY, SNMP_CALLBACK_POST_READ_CONFIG,
                      NULL);
}

void
read_premib_configs (void)
{
  DEBUGMSGTL(("read_config","reading premib configuration tokens\n"));

  if (!ds_get_boolean(DS_LIBRARY_ID, DS_LIB_DONT_READ_CONFIGS))
    read_config_files(PREMIB_CONFIG);

  snmp_call_callbacks(SNMP_CALLBACK_LIBRARY,
                      SNMP_CALLBACK_POST_PREMIB_READ_CONFIG,
                      NULL);
}




/*******************************************************************-o-******
 * read_config_files
 *
 * Parameters:
 *	when	== PREMIB_CONFIG, NORMAL_CONFIG  -or-  EITHER_CONFIG
 *
 *
 * Traverse the list of config file types, performing the following actions
 * for each --
 *
 * First, build a search path for config files.  If the contents of 
 * environment variable SNMPCONFPATH are NULL, then use the following
 * path list (where the last entry exists only if HOME is non-null):
 *
 *	SNMPSHAREPATH:SNMPLIBPATH:${HOME}/.snmp
 *
 * Then, In each of these directories, read config files by the name of:
 *
 *	<dir>/<fileHeader>.conf		-AND-
 *	<dir>/<fileHeader>.local.conf
 *
 * where <fileHeader> is taken from the config file type structure.
 *
 *
 * PREMIB_CONFIG causes free_config() to be invoked prior to any other action.
 *
 *
 * EXITs if any 'config_errors' are logged while parsing config file lines.
 */
void
read_config_files (int when)
{
#ifndef ECOSFIXME_NEEDFILESYSTEM

  int i, j;
  char configfile[300];
  char *envconfpath, *homepath;
  char *cptr1, *cptr2;
  char defaultPath[SPRINT_MAX_LEN];

  struct config_files *ctmp = config_files;
  struct config_line *ltmp;
  struct stat statbuf;
  
  if (when == PREMIB_CONFIG)
    free_config();

  /* read all config file types */
  for(;ctmp != NULL; ctmp = ctmp->next) {

    ltmp = ctmp->start;

    /* read the config files */
    if ((envconfpath = getenv("SNMPCONFPATH")) == NULL) {
      homepath=getenv("HOME");
      sprintf(defaultPath,"%s%c%s%c%s%s%s%s%c%s",
	      SNMPCONFPATH, ENV_SEPARATOR_CHAR,
              SNMPSHAREPATH, ENV_SEPARATOR_CHAR, SNMPLIBPATH,
              ((homepath == NULL) ? "" : ENV_SEPARATOR),
              ((homepath == NULL) ? "" : homepath),
              ((homepath == NULL) ? "" : "/.snmp"),
              ENV_SEPARATOR_CHAR, PERSISTENT_DIRECTORY);
      envconfpath = defaultPath;
    }
    envconfpath = strdup(envconfpath);  /* prevent actually writing in env */
    DEBUGMSGTL(("read_config","config path used:%s\n", envconfpath));
    cptr1 = cptr2 = envconfpath;
    i = 1;
    while (i && *cptr2 != 0) {
      while(*cptr1 != 0 && *cptr1 != ENV_SEPARATOR_CHAR)
        cptr1++;
      if (*cptr1 == 0)
        i = 0;
      else
        *cptr1 = 0;
      /*
       * for proper persistent storage retrival, we need to read old backup
       * copies of the previous storage files.  If the application in
       * question has died without the proper call to snmp_clean_persistent,
       * then we read all the configuration files we can, starting with
       * the oldest first.
       */
      if (strncmp(cptr2, PERSISTENT_DIRECTORY,
                  strlen(PERSISTENT_DIRECTORY)) == 0 ||
          (getenv("SNMP_PERSISTENT_FILE") != NULL &&
           strncmp(cptr2, getenv("SNMP_PERSISTENT_FILE"),
                   strlen(getenv("SNMP_PERSISTENT_FILE"))) == 0)) {
        /* limit this to the known storage directory only */
        for(j=0; j <= MAX_PERSISTENT_BACKUPS; j++) {
          sprintf(configfile,"%s/%s.%d.conf",cptr2, ctmp->fileHeader, j);
          if (stat(configfile, &statbuf) != 0) {
            /* file not there, continue */
            break;
          } else {
            /* backup exists, read it */
            DEBUGMSGTL(("read_config_files","old config file found: %s, parsing\n", configfile));
            read_config (configfile, ltmp, when);
          }
        }
      }
      sprintf(configfile,"%s/%s.conf",cptr2, ctmp->fileHeader);
      read_config (configfile, ltmp, when);
      sprintf(configfile,"%s/%s.local.conf",cptr2, ctmp->fileHeader);
      read_config (configfile, ltmp, when);
      cptr2 = ++cptr1;
    }
    free(envconfpath);
  }
  
  if (config_errors) {
    snmp_log(LOG_ERR, "ucd-snmp: %d errors in config file\n", config_errors);
/*    exit(1); */
  }
#endif
}

void read_config_print_usage(const char *lead)
{
  struct config_files *ctmp = config_files;
  struct config_line *ltmp;

  if (lead == NULL)
    lead = "";

  for(ctmp = config_files; ctmp != NULL; ctmp = ctmp->next) {
    snmp_log(LOG_INFO, "%sIn %s.conf and %s.local.conf:\n", lead, ctmp->fileHeader,
            ctmp->fileHeader);
    for(ltmp = ctmp->start; ltmp != NULL; ltmp = ltmp->next) {
      if (ltmp->help != NULL)
        snmp_log(LOG_INFO, "%s%s%-15s %s\n", lead, lead, ltmp->config_token,
                 ltmp->help);
    }
  }
}

/*******************************************************************-o-******
 * read_config_store
 *
 * Parameters:
 *	*type
 *	*line
 *      
 * 
 * Append line to a file named either ENV(SNMP_PERSISTENT_FILE) or
 *   "<PERSISTENT_DIRECTORY>/<type>.conf".
 * Add a trailing newline to the stored file if necessary.
 *
 * Intended for use by applications to store permenant configuration 
 * information generated by sets or persistent counters.
 *
 */
void
read_config_store(const char *type, const char *line)
{
#ifdef PERSISTENT_DIRECTORY
  char file[512], *filep;
  FILE *fout;
#ifdef PERSISTENT_MASK
  mode_t oldmask;
#endif

  /* store configuration directives in the following order of preference:
     1. ENV variable SNMP_PERSISTENT_FILE
     2. configured <PERSISTENT_DIRECTORY>/<type>.conf
  */
  if ((filep = getenv("SNMP_PERSISTENT_FILE")) == NULL) {
    sprintf(file,"%s/%s.conf",PERSISTENT_DIRECTORY,type);
    filep = file;
  }
  
#ifdef PERSISTENT_MASK
  oldmask = umask(PERSISTENT_MASK);
#endif
  if (mkdirhier(filep, AGENT_DIRECTORY_MODE, 1)) {
      snmp_log(LOG_ERR, "Failed to create the persistent directory for %s\n",
               file);
  }
  if ((fout = fopen(filep, "a")) != NULL) {
    fprintf(fout,line);
    if (line[strlen(line)] != '\n')
      fprintf(fout,"\n");
    DEBUGMSGTL(("read_config","storing: %s\n",line));
    fclose(fout);
  } else {
    DEBUGMSGTL(("read_config","open failure"));
  }
#ifdef PERSISTENT_MASK
  umask(oldmask);
#endif

#endif
}  /* end read_config_store() */

void
read_app_config_store(const char *line)
{
  read_config_store(ds_get_string(DS_LIBRARY_ID, DS_LIB_APPTYPE), line);
}




/*******************************************************************-o-******
 * snmp_save_persistent
 *
 * Parameters:
 *	*type
 *      
 *
 * Save the file "<PERSISTENT_DIRECTORY>/<type>.conf" into a backup copy
 * called "<PERSISTENT_DIRECTORY>/<type>.%d.conf", which %d is an
 * incrementing number on each call, but less than MAX_PERSISTENT_BACKUPS.
 *
 * Should be called just before all persistent information is supposed to be
 * written to move aside the existing persistent cache.
 * snmp_clean_persistent should then be called afterward all data has been
 * saved to remove these backup files.
 *
 * Note: on an rename error, the files are removed rather than saved.
 *
 */
void
snmp_save_persistent(const char *type)
{
#ifndef ECOSFIXME_NEEDFILESYSTEM

  char file[512], fileold[512];
  struct stat statbuf;
  int j;

  DEBUGMSGTL(("snmp_save_persistent","saving %s files...\n", type));
  sprintf(file,"%s/%s.conf", PERSISTENT_DIRECTORY, type);
  if (stat(file, &statbuf) == 0) {
    for(j=0; j <= MAX_PERSISTENT_BACKUPS; j++) {
      sprintf(fileold,"%s/%s.%d.conf", PERSISTENT_DIRECTORY, type, j);
      if (stat(fileold, &statbuf) != 0) {
        DEBUGMSGTL(("snmp_save_persistent"," saving old config file: %s -> %s.\n", file, fileold));
        if (rename(file, fileold)) {
          unlink(file);/* moving it failed, try nuking it, as leaving
                          it around is very bad. */
        }
        break;
      }
    }
  }
#endif
}


/*******************************************************************-o-******
 * snmp_clean_persistent
 *
 * Parameters:
 *	*type
 *      
 *
 * Unlink all backup files called "<PERSISTENT_DIRECTORY>/<type>.%d.conf".
 *
 * Should be called just after we successfull dumped the last of the
 * persistent data, to remove the backup copies of previous storage dumps.
 *
 * XXX  Worth overwriting with random bytes first?  This would
 *	ensure that the data is destroyed, even a buffer containing the
 *	data persists in memory or swap.  Only important if secrets
 *	will be stored here.
 */
void
snmp_clean_persistent(const char *type)
{
#ifndef ECOSFIXME_NEEDFILESYSTEM

  char file[512];
  struct stat statbuf;
  int j;

  DEBUGMSGTL(("snmp_clean_persistent","cleaning %s files...\n", type));
  sprintf(file,"%s/%s.conf",PERSISTENT_DIRECTORY,type);
  if (stat(file, &statbuf) == 0) {
    for(j=0; j <= MAX_PERSISTENT_BACKUPS; j++) {
      sprintf(file,"%s/%s.%d.conf", PERSISTENT_DIRECTORY, type, j);
      if (stat(file, &statbuf) == 0) {
        DEBUGMSGTL(("snmp_clean_persistent"," removing old config file: %s\n", file));
        unlink(file);
      }
    }
  }
#endif
}
  



/* config_perror: prints a warning string associated with a file and
   line number of a .conf file and increments the error count. */
void config_perror(const char *string)
{
  config_pwarn(string);
  config_errors++;
}

void config_pwarn(const char *string)
{
  snmp_log(LOG_WARNING, "%s: line %d: %s\n", curfilename, linecount, string);
}

/* skip all white spaces and return 1 if found something either end of
   line or a comment character */
char *skip_white(char *ptr)
{

  if (ptr == NULL) return (NULL);
  while (*ptr != 0 && isspace(*ptr)) ptr++;
  if (*ptr == 0 || *ptr == '#') return (NULL);
  return (ptr);
}

char *skip_not_white(char *ptr)
{
  
  if (ptr == NULL) return (NULL);
  while (*ptr != 0 && !isspace(*ptr)) ptr++;
  if (*ptr == 0 || *ptr == '#') return (NULL);
  return (ptr);
}

char *skip_token(char *ptr)
{
  ptr = skip_white(ptr);
  ptr = skip_not_white(ptr);
  ptr = skip_white(ptr);
  return (ptr);
}

/* copy_word
   copies the next 'token' from 'from' into 'to'.
   currently a token is anything seperate by white space
   or within quotes (double or single) (i.e. "the red rose" 
   is one token, \"the red rose\" is three tokens)
   a '\' character will allow a quote character to be treated
   as a regular character 
   It returns a pointer to first non-white space after the end of the token
   being copied or to 0 if we reach the end.*/

char *copy_word(char *from, char *to)
{
  char quote;
  if ( (*from == '\"') || (*from =='\'') ){
    quote = *(from++);
    while ( (*from != quote) && (*from != 0) ) {
      if ((*from == '\\') && (*(from+1) != 0)) {
	*to++ = *(from+1);
	from = from +2;
      }
      else  *to++ = *from++;
    }
    if (*from == 0) {
      DEBUGMSGTL(("read_config_copy_word",
                  "no end quote found in config string\n"));
    } else from++;
  }
  else {
    while (*from != 0 && !isspace(*from)) {
      if ((*from == '\\') && (*(from+1) != 0)) {
	*to++ = *(from+1);
	from = from +2;
      }
      else  *to++ = *from++;
    }
  }
  *to = 0;
  from = skip_white(from);
  return(from);
}  /* copy_word */

/* read_config_save_octet_string(): saves an octet string as a length
   followed by a string of hex */
char *read_config_save_octet_string(char *saveto, u_char *str, size_t len) {
  int i;
  if (str != NULL) {
    sprintf(saveto, "0x");
    saveto += 2;
    for(i = 0; i < (int)len; i++) {
      sprintf(saveto,"%02x", str[i]);
      saveto = saveto + 2;
    }
    return saveto;
  } else {
    sprintf(saveto,"\"\"");
    saveto += 2;
  }
  return saveto;
}

/* read_config_read_octet_string(): reads an octet string that was
   saved by the read_config_save_octet_string() function */
char *read_config_read_octet_string(char *readfrom, u_char **str, size_t *len) {
  u_char *cptr=NULL;
  char *cptr1;
  u_int tmp;
  int i;

  if (readfrom == NULL || str == NULL)
    return NULL;
  
  if (strncasecmp(readfrom,"0x",2) == 0) {
    /* A hex string submitted. How long? */
    readfrom += 2;
    cptr1 = skip_not_white(readfrom);
    if (cptr1)
      *len = (cptr1 - readfrom);
    else
      *len = strlen(readfrom);

    if (*len % 2) {
      DEBUGMSGTL(("read_config_read_octet_string","invalid hex string: wrong length"));
      return NULL;
    }
    *len = *len / 2;

    /* malloc data space if needed */
    if (*str == NULL) {
      if (*len == 0) {
        /* null length string found */
        cptr = NULL;

      } else if (*len > 0 && (str == NULL || (cptr = (u_char *)malloc(*len)) == NULL)) {
        return NULL;
      }
      *str = cptr;
    } else {
      cptr = *str;
    }

    /* copy data */
    for(i = 0; i < (int)*len; i++) {
      sscanf(readfrom,"%2x",&tmp);
      *cptr++ = (u_char) tmp;
      readfrom += 2;
    }
    readfrom = skip_white(readfrom);
  } else {
    /* Normal string */

    /* malloc data space if needed */
    if (*str == NULL) {
      char buf[SNMP_MAXBUF];
      readfrom = copy_word(readfrom, buf);

      *len = strlen(buf);
      /* malloc an extra space to add a null */
      if (*len > 0 && (str == NULL ||
                       (cptr = (u_char *) malloc(*len + 1))
                       == NULL))
        return NULL;
      *str = cptr;
      if (cptr)
        memcpy(cptr, buf, (*len+1));
    } else {
      readfrom = copy_word(readfrom, (char *)*str);
    }
  }

  return readfrom;
}


/* read_config_save_objid(): saves an objid as a numerical string */
char *read_config_save_objid(char *saveto, oid *objid, size_t len) {
  int i;
  
  if (len == 0) {
    strcat(saveto, "NULL");
    saveto += strlen(saveto);
    return saveto;
  }

  /* in case len=0, this makes it easier to read it back in */
  for(i=0; i < (int)len; i++) {
    sprintf(saveto,".%ld", objid[i]);
    saveto += strlen(saveto);
  }
  return saveto;
}

/* read_config_read_objid(): reads an objid from a format saved by the above */
char *read_config_read_objid(char *readfrom, oid **objid, size_t *len) {

  if (objid == NULL || readfrom == NULL)
    return NULL;

  if (*objid != NULL) {
    char buf[SPRINT_MAX_LEN];

    if (strncmp(readfrom,"NULL",4) == 0) {
      /* null length oid */
      *len = 0;
    } else {
      /* read_objid is touchy with trailing stuff */
      copy_word(readfrom, buf);

      /* read the oid into the buffer passed to us */
      if (!read_objid(buf, *objid, len)) {
        DEBUGMSGTL(("read_config_read_objid","Invalid OID"));
        return NULL;
      }
    }
    
    readfrom = skip_token(readfrom);
  } else {
    if (strncmp(readfrom,"NULL",4) == 0) {
      /* null length oid */
      *len = 0;
      readfrom = skip_token(readfrom);
    } else {
      /* space needs to be malloced.  Call ourself recursively to figure
       out how long the oid actually is */
      oid obuf[MAX_OID_LEN];
      size_t obuflen = MAX_OID_LEN;
      oid *oidp = obuf;
      oid **oidpp = &oidp;   /* done this way for odd, untrue, gcc warnings */

      readfrom = read_config_read_objid(readfrom, oidpp, &obuflen);

      /* Then malloc and copy the results */
      *len = obuflen;
      if (*len > 0 && (*objid = (oid*)malloc(*len * sizeof(oid))) == NULL)
        return NULL;

      if (obuflen > 0)
        memcpy(*objid, obuf, obuflen*sizeof(oid));
    }
  }
  return readfrom;
}

/* read_config_read_data():
   reads data of a given type from a token(s) on a configuration line.

   Returns: character pointer to the next token in the configuration line.
            NULL if none left.
            NULL if an unknown type.
*/
char *read_config_read_data(int type, char *readfrom, void *dataptr, size_t *len) {

  int *intp;
  char **charpp;
  oid  **oidpp;

  if (dataptr == NULL || readfrom == NULL)
    return NULL;
  
  switch(type) {
    case ASN_INTEGER:
      intp = (int *) dataptr;
      *intp = atoi(readfrom);
      readfrom = skip_token(readfrom);
      return readfrom;
      
    case ASN_OCTET_STR:
      charpp = (char **) dataptr;
      return read_config_read_octet_string(readfrom, (u_char **) charpp, len);

    case ASN_OBJECT_ID:
      oidpp = (oid **) dataptr;
      return read_config_read_objid(readfrom, oidpp, len);

    default:
      DEBUGMSGTL(("read_config_read_data","Fail: Unknown type: %d", type));
      return NULL;
  }
  return NULL;
}

/* read_config_read_data():
   reads data of a given type from a token(s) on a configuration line.

   Returns: character pointer to the next token in the configuration line.
            NULL if none left.
            NULL if an unknown type.
*/
char *read_config_store_data(int type, char *storeto, void *dataptr, size_t *len) {

  int *intp;
  u_char **charpp;
  oid  **oidpp;

  if (dataptr == NULL || storeto == NULL)
    return NULL;
  
  switch(type) {
    case ASN_INTEGER:
      intp = (int *) dataptr;
      sprintf(storeto," %d", *intp);
      return (storeto + strlen(storeto));
      
    case ASN_OCTET_STR:
      charpp = (u_char **) dataptr;
      return read_config_save_octet_string(storeto, *charpp, *len);

    case ASN_OBJECT_ID:
      oidpp = (oid **) dataptr;
      return read_config_save_objid(storeto, *oidpp, *len);

    default:
      DEBUGMSGTL(("read_config_store_data","Fail: Unknown type: %d", type));
      return NULL;
  }
  return NULL;
}
