/*
 * Copyright (C) 2012 by Darren Reed.
 *
 * See the IPFILTER.LICENCE file for details on licencing.
 *
 * $Id: load_file.c,v 1.6.2.2 2012/07/22 08:04:24 darren_r Exp $
 */

#include "ipf.h"
#include <ctype.h>

alist_t *
load_file(char *filename)
{
        alist_t *a, *rtop, *rbot;
        char *s, line[1024], *t;
        int linenum, not;
        FILE *fp;

        fp = fopen(filename + 7, "r");
        if (fp == NULL) {
                fprintf(stderr, "load_file cannot open '%s'\n", filename);
                return (NULL);
        }

        a = NULL;
        rtop = NULL;
        rbot = NULL;
        linenum = 0;

        while (fgets(line, sizeof(line) - 1, fp)) {
                line[sizeof(line) - 1] = '\0';
                linenum++;
                /*
                 * Hunt for CR/LF.  If no LF, stop processing.
                 */
                s = strchr(line, '\n');
                if (s == NULL) {
                        fprintf(stderr, "%d:%s: line too long\n",
                                linenum, filename);
                        fclose(fp);
                        alist_free(rtop);
                        return (NULL);
                }

                /*
                 * Remove trailing spaces
                 */
                for (; ISSPACE(*s); s--)
                        *s = '\0';

                s = strchr(line, '\r');
                if (s != NULL)
                        *s = '\0';
                for (t = line; ISSPACE(*t); t++)
                        ;
                if (*t == '!') {
                        not = 1;
                        t++;
                } else
                        not = 0;

                /*
                 * Remove comment markers
                 */
                s = strchr(t, '#');
                if (s != NULL) {
                        *s = '\0';
                        if (s == t)
                                continue;
                }

                /*
                 * Trim off tailing white spaces
                 */
                s = strlen(t) + t - 1;
                while (ISSPACE(*s))
                        *s-- = '\0';

                a = alist_new(AF_UNSPEC, t);
                if (a != NULL) {
                        a->al_not = not;
                        if (rbot != NULL)
                                rbot->al_next = a;
                        else
                                rtop = a;
                        rbot = a;
                } else {
                        fprintf(stderr, "%s:%d unrecognised content :%s\n",
                                filename, linenum, t);
                }
        }
        fclose(fp);

        return (rtop);
}