%{
/* strongSwan config file parser (parser.y)
 * Copyright (C) 2001 Mathieu Lafon - Arkoon Network Security
 *
 * 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.  See <http://www.fsf.org/copyleft/gpl.txt>.
 *
 * 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.
 *
 * RCSID $Id: parser.y,v 1.6 2006/01/17 23:43:36 as Exp $
 */

#include <stdio.h>
#include <stdlib.h>
#include <string.h>

#include <freeswan.h>

#include "../pluto/constants.h"
#include "../pluto/defs.h"
#include "../pluto/log.h"
#include "parser.h"

#define YYERROR_VERBOSE
#define ERRSTRING_LEN	256

/**
 * Bison
 */
static char parser_errstring[ERRSTRING_LEN+1];

extern void yyerror(const char *s);
extern int yylex (void);
extern void _parser_y_error(char *b, int size, const char *s);

/**
 * Static Globals
 */
static int _save_errors_;
static config_parsed_t *_parser_cfg;
static kw_list_t **_parser_kw, *_parser_kw_last;
static char errbuf[ERRSTRING_LEN+1];

/**
 * Gperf
 */
extern kw_entry_t *in_word_set (char *str, unsigned int len);

%}

%union { char *s; };
%token EQUAL FIRST_SPACES EOL CONFIG SETUP CONN CA INCLUDE FILE_VERSION
%token <s> STRING

%%

/*
 * Config file
 */

config_file:
    config_file section_or_include
    | /* NULL */		
    ;

section_or_include:
    FILE_VERSION STRING EOL
    {
	free($2);
    }
    | CONFIG SETUP EOL
    {
	_parser_kw = &(_parser_cfg->config_setup);
	_parser_kw_last = NULL;
    } kw_section
    | CONN STRING EOL
    {
	section_list_t *section = (section_list_t *)alloc_thing(section_list_t
							     , "section_list_t");
	
	section->name = clone_str($2, "conn section name");
	section->kw = NULL;
	section->next = NULL;
	_parser_kw = &(section->kw);
	if (!_parser_cfg->conn_first)
	    _parser_cfg->conn_first = section;
	if (_parser_cfg->conn_last)
	    _parser_cfg->conn_last->next = section;
	_parser_cfg->conn_last = section;
	_parser_kw_last = NULL;
	free($2);
    } kw_section
    | CA STRING EOL
    {
	section_list_t *section = (section_list_t *)alloc_thing(section_list_t
							     , "section_list_t");
	section->name = clone_str($2, "ca section name");
	section->kw = NULL;
	section->next = NULL;
	_parser_kw = &(section->kw);
	if (!_parser_cfg->ca_first)
	    _parser_cfg->ca_first = section;
	if (_parser_cfg->ca_last)
	    _parser_cfg->ca_last->next = section;
	_parser_cfg->ca_last = section;
	_parser_kw_last = NULL;
	free($2);
    } kw_section
    | INCLUDE STRING
    {
	extern void _parser_y_include (const char *f);
	_parser_y_include($2);
	free($2);
    } EOL
    | EOL
    ;

kw_section:
    FIRST_SPACES statement_kw EOL kw_section
    |
    ;

statement_kw:
    STRING EQUAL STRING
    {
	kw_list_t  *new;
	kw_entry_t *entry = in_word_set($1, strlen($1));

	if (entry == NULL)
	{
	    snprintf(errbuf, ERRSTRING_LEN, "unknown keyword '%s'", $1);
	    yyerror(errbuf);
	}
	else if (_parser_kw)
	{
	    new = (kw_list_t *)alloc_thing(kw_list_t, "kw_list_t");
	    new->entry = entry;
	    new->value = clone_str($3, "kw_list value");
	    new->next = NULL;
	    if (_parser_kw_last)
		_parser_kw_last->next = new;
	    _parser_kw_last = new;
	    if (!*_parser_kw)
		*_parser_kw = new;
	}
	free($1);
	free($3);
    }
    | STRING EQUAL
      {
	free($1);
      }
    |
    ;

%%

void
yyerror(const char *s)
{
    if (_save_errors_)
	_parser_y_error(parser_errstring, ERRSTRING_LEN, s);
}

config_parsed_t *
parser_load_conf(const char *file)
{
    config_parsed_t *cfg = NULL;
    int err = 0;
    FILE *f;

    extern void _parser_y_init (const char *f);
    extern FILE *yyin;

    memset(parser_errstring, 0, ERRSTRING_LEN+1);

    cfg = (config_parsed_t *)alloc_thing(config_parsed_t, "config_parsed_t");
    if (cfg)
    {
	memset(cfg, 0, sizeof(config_parsed_t));
	f = fopen(file, "r");
	if (f)
	{
	    yyin = f;
	    _parser_y_init(file);
	    _save_errors_ = 1;
	    _parser_cfg = cfg;

	    if (yyparse() !=0 )
	    {
		if (parser_errstring[0] == '\0')
		{
		    snprintf(parser_errstring, ERRSTRING_LEN, "Unknown error...");
		}
		_save_errors_ = 0;
		while (yyparse() != 0);
		err++;
	    }
	    else if (parser_errstring[0] != '\0')
	    {
		err++;
	    }
	    else
	    {
		/**
		 * Config valid
		 */
	    }

	    fclose(f);
	}
	else
	{
	    snprintf(parser_errstring, ERRSTRING_LEN, "can't load file '%s'", file);
	    err++;
	}
    }
    else
    {
	snprintf(parser_errstring, ERRSTRING_LEN, "can't allocate memory");
	err++;
    }

    if (err)
    {
	plog("%s", parser_errstring);

	if (cfg)
	    parser_free_conf(cfg);
	cfg = NULL;
    }

    return cfg;
}

static void
parser_free_kwlist(kw_list_t *list)
{
    kw_list_t *elt;

    while (list)
    {
	elt = list;
	list = list->next;
	if (elt->value)
	    pfree(elt->value);
	pfree(elt);
    }
}

void
parser_free_conf(config_parsed_t *cfg)
{
    section_list_t *sec;
    if (cfg)
    {
	parser_free_kwlist(cfg->config_setup);
	while (cfg->conn_first)
	{
	    sec = cfg->conn_first;
	    cfg->conn_first = cfg->conn_first->next;
	    if (sec->name)
		pfree(sec->name);
	    parser_free_kwlist(sec->kw);
	    pfree(sec);
	}
	while (cfg->ca_first)
	{
	    sec = cfg->ca_first;
	    cfg->ca_first = cfg->ca_first->next;
	    if (sec->name)
		pfree(sec->name);
	    parser_free_kwlist(sec->kw);
	    pfree(sec);
	}
	pfree(cfg);
    }
}