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* Software License Agreement (BSD License)                                                               *
* Author: Sebastien Decugis <sdecugis@freediameter.net>							 *
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* Copyright (c) 2013, WIDE Project and NICT								 *
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/* Yacc extension's configuration parser.
 * See doc/acl_wl.conf.sample for configuration file format
 */

/* For development only : */
%debug 
%error-verbose

/* The parser receives the configuration file filename as parameter */
%parse-param {char * conffile}

/* Keep track of location */
%locations 
%pure-parser

%{
#include "acl_wl.h"
#include "aw_conf.tab.h"	/* bison is not smart enough to define the YYLTYPE before including this code, so... */

#include <string.h>
#include <errno.h>

/* Forward declaration */
int yyparse(char * conffile);

static int fqdn_added = 0;

/* Parse the configuration file */
int aw_conf_handle(char * conffile)
{
	extern FILE * aw_confin;
	int ret;
	
	TRACE_ENTRY("%p", conffile);
	
	TRACE_DEBUG (FULL, "Parsing configuration file: %s...", conffile);
	
	aw_confin = fopen(conffile, "r");
	if (aw_confin == NULL) {
		ret = errno;
		fd_log_debug("Unable to open extension configuration file %s for reading: %s", conffile, strerror(ret));
		TRACE_DEBUG (INFO, "Error occurred, message logged -- configuration file.");
		return ret;
	}

	ret = yyparse(conffile);

	fclose(aw_confin);

	if (ret != 0) {
		TRACE_DEBUG (INFO, "Unable to parse the configuration file.");
		return EINVAL;
	} else {
		TRACE_DEBUG(FULL, "Read %d FQDN entries successfully.", fqdn_added);
	}
	
	return 0;
}

/* The Lex parser prototype */
int aw_conflex(YYSTYPE *lvalp, YYLTYPE *llocp);

/* Function to report the errors */
void yyerror (YYLTYPE *ploc, char * conffile, char const *s)
{
	TRACE_DEBUG(INFO, "Error in configuration parsing");
	
	if (ploc->first_line != ploc->last_line)
		fd_log_debug("%s:%d.%d-%d.%d : %s", conffile, ploc->first_line, ploc->first_column, ploc->last_line, ploc->last_column, s);
	else if (ploc->first_column != ploc->last_column)
		fd_log_debug("%s:%d.%d-%d : %s", conffile, ploc->first_line, ploc->first_column, ploc->last_column, s);
	else
		fd_log_debug("%s:%d.%d : %s", conffile, ploc->first_line, ploc->first_column, s);
}

%}

/* Values returned by lex for token */
%union {
	char 		 *string;
}

/* In case of error in the lexical analysis */
%token 		LEX_ERROR

/* Key words */
%token <string>	FQDN


/* -------------------------------------- */
%%

	/* The grammar definition */
conffile:		/* empty grammar is OK */
			| conffile FQDN
			{
				fqdn_added++;
				TRACE_DEBUG(FULL, "Added FQDN: %s", $2);
			}
			| conffile LEX_ERROR
			{
				yyerror(&yylloc, conffile, "An error occurred while parsing the configuration file");
				return EINVAL;
			}
			;