set.c

/*
   Functions to set/search/unset variables.

   Copyright (C) Stephen Fegan 1995, 1996

   This program 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 of the License, or (at your option) any later
   version.
   
   This program 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
   this program; if not, write to the Free Software Foundation, Inc., 675 Mass
   Ave, Cambridge, MA 02139, USA.
   
   please send patches or advice on flash to: `flash@netsoc.ucd.ie'
   */

#include<string.h>
#include<stdio.h>
#include<stdlib.h>
#include<termios.h>
#include<unistd.h>
#include<pwd.h>

#include"set.h"
#include"tree.h"
#include"misc.h"

struct dict *SetVariables;

static int Set_name_compare(void *a,void *b)
{
  return strcmp(((struct set_node *)a)->variable,((struct set_node *)b)->variable);
}

int find_variable(char *key, char **data)
{
  struct set_node k,*x;
  k.variable=key;
  k.value=NULL;

  if(data!=NULL)*data=NULL;

  if(SetVariables==NULL)return 0;

  x=(struct set_node *)find_node(SetVariables,&k);

  if((x==NULL)||((x->flags & SF_SET) == 0))return 0;
  else
    {
      if(data!=NULL)*data=x->value;
      return 1;
    }
}

void set_variable(char *key,char *data,int resettable)
{
  struct set_node *k,*x;

  k=(struct set_node *)xmalloc(sizeof(*k));
  k->variable=xmalloc(strlen(key)+1);
  strcpy(k->variable,key);

  if(data!=NULL)
    {
      k->value=xmalloc(strlen(data)+1);
      strcpy(k->value,data);
    }
  else k->value=NULL;

  k->flags = SF_SET;
  if(!resettable)k->flags |= SF_NORESET;

  if(SetVariables==NULL)SetVariables=new_dict(Set_name_compare);
  
  if(!add_unique_node(SetVariables,(void *)k))
    {
      x=find_node(SetVariables,(void *)k);
      if((x->flags & SF_NORESET)==0)
	x=change_node(SetVariables,(void *)k);
      else x=k;
      free(x);
    }
}

void unset_variable(char *key)
{
  struct set_node k,*x;

  k.variable=key;
  k.value=NULL;

  if(SetVariables==NULL)return;

  x=find_node(SetVariables,&k);
  if((x!=NULL)&&((x->flags & SF_NORESET)==0))
    x->flags &= !(SF_SET | SF_NORESET);
      
  return;
}

void global_variables(void)
{
  struct passwd *pw;
  char temp[40];

  pw=getpwuid(getuid());

  sprintf(temp,"%d",pw->pw_uid);
  set_variable("uid",temp,0);
  set_variable("user",pw->pw_name,0);
  set_variable("home",pw->pw_dir,0);

  set_variable("tty",ttyname(0),0);
}