#include <config.h>

#ifdef CAN_USE_NLIST

#if HAVE_STDLIB_H
#include <stdlib.h>
#endif
#include <stdio.h>
#include <errno.h>
#include <fcntl.h>
#include <netinet/in.h>
#ifdef HAVE_NLIST_H
#include <nlist.h>
#endif
#if HAVE_KVM_H
#include <kvm.h>
#endif

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

#include "auto_nlist.h"
#include "autonlist.h"
#include "kernel.h"
#include "../snmplib/system.h"

#include "asn1.h"
#include "snmp_api.h"
#include "snmp_debug.h"
#include "snmp_logging.h"
#include "default_store.h"
#include "ds_agent.h"

struct autonlist *nlists = 0;
static void init_nlist (struct nlist *);

long
auto_nlist_value(const char *string)
{
  struct autonlist **ptr, *it=0;
  int cmp;

  if (string == 0)
    return 0;

  ptr = &nlists;
  while(*ptr != 0 && it == 0) {
    cmp = strcmp((*ptr)->symbol, string);
    if (cmp == 0)
      it = *ptr;
    else if (cmp < 0) {
      ptr = &((*ptr)->left);
    } else {
      ptr = &((*ptr)->right);
    }
  }
  if (*ptr == 0) {
    *ptr = (struct autonlist *) malloc(sizeof (struct autonlist));
    it = *ptr;
    it->left = 0;
    it->right = 0;
    it->symbol = (char *) malloc(strlen(string)+1);
    strcpy(it->symbol,string);
    /* allocate an extra byte for inclusion of a preceding '_' later */
    it->nl[0].n_name = (char *) malloc(strlen(string)+2);
#ifdef aix4
    strcpy(it->nl[0].n_name,string);
#else
    sprintf(it->nl[0].n_name,"_%s",string);
#endif
    it->nl[1].n_name = 0;
    init_nlist(it->nl);
#ifndef aix4
    if (it->nl[0].n_type == 0) {
      strcpy(it->nl[0].n_name,string);
      init_nlist(it->nl);
    }
#endif
    if (it->nl[0].n_type == 0) {
      if (!ds_get_boolean(DS_APPLICATION_ID, DS_AGENT_NO_ROOT_ACCESS))
          snmp_log(LOG_ERR, "nlist err: neither %s nor _%s found.\n", string, string);
      return( -1 );
    } else {
      DEBUGMSGTL(("auto_nlist", "nlist:  found symbol %s at %x.\n", it->symbol, it->nl[0].n_value));
      return( it->nl[0].n_value );
    }
  }
  else
    return( it->nl[0].n_value );
}

int
auto_nlist(const char *string,
	   char *var,
	   int size)
{
  long result;
  int ret;
  result = auto_nlist_value(string);
  if (result != -1) {
    if (var != NULL) {
      ret = klookup(result, var, size);
      if (!ret)
        snmp_log(LOG_ERR, "auto_nlist failed on %s at location %lx\n",
               string, result);
      return ret;
    } else
      return 1;
  }
  return 0;
}
 
static void
init_nlist(struct nlist nl[])
{
#ifdef CAN_USE_NLIST
  int ret;
#if HAVE_KVM_OPENFILES
  kvm_t *kernel;
  char kvm_errbuf[4096];

  if((kernel = kvm_openfiles(KERNEL_LOC, NULL, NULL, O_RDONLY, kvm_errbuf)) == NULL) {
      if (ds_get_boolean(DS_APPLICATION_ID, DS_AGENT_NO_ROOT_ACCESS))
        return;
      else {
        snmp_log_perror("kvm_openfiles");
        snmp_log(LOG_ERR, "kvm_openfiles: %s\n", kvm_errbuf);
        exit(1);
      }
  }
  if ((ret = kvm_nlist(kernel, nl)) == -1) {
      if (ds_get_boolean(DS_APPLICATION_ID, DS_AGENT_NO_ROOT_ACCESS))
        return;
      else {
        snmp_log_perror("kvm_nlist");
        exit(1);
      }
  }
  kvm_close(kernel);
#else /* ! HAVE_KVM_OPENFILES */
#if defined(aix4) && defined(HAVE_KNLIST)
  if ( knlist(nl,1,sizeof(struct nlist)) == -1) {
    DEBUGMSGTL(("auto_nlist", "knlist failed on symbol:  %s\n", nl[0].n_name));
    if ( errno == EFAULT ) {
        nl[0].n_type = 0;
        nl[0].n_value = 0;
    } else {
        snmp_log_perror("knlist");
      if (ds_get_boolean(DS_APPLICATION_ID, DS_AGENT_NO_ROOT_ACCESS))
        return;
      else
        exit(1);
    }
  }
#else
  if ((ret = nlist(KERNEL_LOC,nl)) == -1) {
    if (ds_get_boolean(DS_APPLICATION_ID, DS_AGENT_NO_ROOT_ACCESS))
      return;
    else {
      snmp_log_perror("nlist");
      exit(1);
    }
  }
#endif /*aix4*/
#endif /* ! HAVE_KVM_OPENFILES */
  for(ret = 0; nl[ret].n_name != NULL; ret++) {
#ifdef aix4
      if (nl[ret].n_type == 0 && nl[ret].n_value != 0)
	nl[ret].n_type = 1;
#endif
      if (nl[ret].n_type == 0) {
        if (!ds_get_boolean(DS_APPLICATION_ID, DS_AGENT_NO_ROOT_ACCESS))
	  DEBUGMSGTL(("auto_nlist", "nlist err:  %s not found\n",nl[ret].n_name));
      } else {
	  DEBUGMSGTL(("auto_nlist", "nlist: %s 0x%X\n", nl[ret].n_name,
                      (unsigned int)nl[ret].n_value));
      }
  }
#endif /* CAN_USE_NLIST */
}

int KNLookup(struct nlist nl[],
	     int nl_which,
	     char *buf,
	     int s)
{ 
    struct nlist *nlp = &nl[nl_which];

    if (nlp->n_value == 0) {
        snmp_log(LOG_ERR, "Accessing non-nlisted variable: %s\n", nlp->n_name);
	nlp->n_value = -1;	/* only one error message ... */
	return 0;
    }
    if (nlp->n_value == -1)
        return 0;

    return klookup(nlp->n_value, buf, s);
}

#ifdef TESTING
void
auto_nlist_print_tree(int indent,
		      struct autonlist *ptr)
{
  char buf[1024];
  if (indent == -2) {
    snmp_log(LOG_ERR, "nlist tree:\n");
    auto_nlist_print_tree(12,nlists);
  } else {
    if (ptr == 0)
      return;
    sprintf(buf,"%%%ds\n",indent);
/*    DEBUGMSGTL(("auto_nlist", "buf: %s\n",buf)); */
    DEBUGMSGTL(("auto_nlist", buf, ptr->symbol));
    auto_nlist_print_tree(indent+2,ptr->left);
    auto_nlist_print_tree(indent+2,ptr->right);
  }
}
#endif
#endif /* CAN_USE_NLIST */