/* This file is part of the Project Athena Zephyr Notification System.
 * It contains source for the ZGetVariable, ZSetVariable, and ZUnsetVariable
 * functions.
 *
 *	Created by:	Robert French
 *
 *	$Source$
 *	$Author$
 *
 *	Copyright (c) 1987 by the Massachusetts Institute of Technology.
 *	For copying and distribution information, see the file
 *	"mit-copyright.h". 
 */
/* $Header$ */

#ifndef lint
static char rcsid_ZVariables_c[] = "$Header$";
#endif lint

#include <zephyr/mit-copyright.h>

#include <zephyr/zephyr_internal.h>

#include <ctype.h>
#include <pwd.h>

#define _toupper(c) (islower(c)?toupper(c):c)

char *ZGetVariable(var)
	char *var;
{
	char varfile[128],*ret,*ptr;
	char *get_varval();
	int i;

	if (get_localvarfile(varfile))
		return ((char *)0);

	if (ret = get_varval(varfile,var))
		return (ret);
	return (get_varval(DEFAULT_VARS_FILE,var));
}

Code_t ZSetVariable(var,value)
	char *var;
	char *value;
{
	int written;
	FILE *fpin,*fpout;
	char varfile[128],varfilebackup[128],varbfr[512];

	written = 0;
	
	if (get_localvarfile(varfile))
		return (ZERR_INTERNAL);

	strcpy(varfilebackup,varfile);
	strcat(varfilebackup,".backup");
	
	if (!(fpout = fopen(varfilebackup,"w"))) {
		fclose(fpin);
		return (errno);
	}
	if (fpin = fopen(varfile,"r")) {
		while (fgets(varbfr,sizeof varbfr,fpin) > 0) {
			if (varbfr[strlen(varbfr)-1] < ' ')
				varbfr[strlen(varbfr)-1] = '\0';
			if (varline(varbfr,var)) {
				fprintf(fpout,"%s = %s\n",var,value);
				written = 1;
			}
			else
				fprintf(fpout,"%s\n",varbfr);
		}
		fclose(fpin);
	} 
	if (!written)
		fprintf(fpout,"%s = %s\n",var,value);
	fclose(fpout);
	if (rename(varfilebackup,varfile))
		return (errno);
	return (ZERR_NONE);
}	

Code_t ZUnsetVariable(var)
	char *var;
{
	FILE *fpin,*fpout;
	char varfile[128],varfilebackup[128],varbfr[512];

	if (get_localvarfile(varfile))
		return (ZERR_INTERNAL);

	strcpy(varfilebackup,varfile);
	strcat(varfilebackup,".backup");
	
	if (!(fpout = fopen(varfilebackup,"w"))) {
		fclose(fpin);
		return (errno);
	}
	if (fpin = fopen(varfile,"r")) {
		while (fgets(varbfr,sizeof varbfr,fpin) > 0) {
			if (varbfr[strlen(varbfr)-1] < ' ')
				varbfr[strlen(varbfr)-1] = '\0';
			if (!varline(varbfr,var))
				fprintf(fpout,"%s\n",varbfr);
		}
		fclose(fpin);
	} 
	fclose(fpout);
	if (rename(varfilebackup,varfile))
		return (errno);
	return (ZERR_NONE);
}	

static get_localvarfile(bfr)
	char *bfr;
{
	char *envptr;
	struct passwd *pwd;

	envptr = (char *)getenv("HOME");
	if (envptr)
		strcpy(bfr,envptr);
	else {
		if (!(pwd = getpwuid(getuid()))) {
			fprintf(stderr,"Zephyr internal failure: Can't find your entry in /etc/passwd\n");
			return (1);
		}
		strcpy(bfr,pwd->pw_dir);
	}

	strcat(bfr,"/");
	strcat(bfr,".zephyr.vars");
	return (0);
} 
	
static char *get_varval(fn,var)
	char *fn;
	char *var;
{
	FILE *fp;
	char varbfr[512];
	int i;
	
	fp = fopen(fn,"r");
	if (!fp)
		return ((char *)0);

	while (fgets(varbfr,sizeof varbfr,fp) > 0) {
		if (varbfr[strlen(varbfr)-1] < ' ')
			varbfr[strlen(varbfr)-1] = '\0';
		if (!(i = varline(varbfr,var)))
			continue;
		fclose(fp);
		return (varbfr+i);
	}
	fclose(fp);
	return ((char *)0);
}

static int varline(bfr,var)
	char *bfr;
	char *var;
{
	int i;
	
	if (!bfr[0] || bfr[0] == '#')
		return (0);
	
	for (i = 0; bfr[i] && !isspace(bfr[i]) &&
	     bfr[i] != '='; i++)
		if (_toupper(bfr[i]) != _toupper(var[i]))
			break;
	if ((!bfr[i] || !isspace(bfr[i])) && bfr[i] != '=')
		return (0);
	while (bfr[i] && isspace(bfr[i]))
		i++;
	if (bfr[i++] != '=')
		return (0);
	while (bfr[i] && isspace(bfr[i]))
		i++;
	return (i);
}