/*
 *	diffregex.cc
 *		第１ファイルをregex として、第２ファイルと diff する。
 *	Sat,18 Oct,2008
 *
 *	Copyright(C)2008 G-HAL
 */

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

#define	MAX_BUF		1024
#define	MAX_MATCH	10


#if !defined(__unused)
# if defined(ATTRIBUTE_UNUSED)
#  define	__unused	ATTRIBUTE_UNUSED
# else
#  define	__unused	__attribute__ ((__unused__))
# endif
#endif

# define		_number_(arr)			(sizeof(arr)/sizeof((arr)[0]))



struct Line {
public:
	bool	hit;
	int		num;
	char*	msg;
	Line*	next;

	static void free( Line* ptr )
	{
		while (ptr) {
			Line* const	next = ptr->next;
			delete[] ptr->msg;
			delete ptr;
			ptr = next;
		}
	}
};



bool diffregex( Line* f1, Line* f2 )
{
	bool		match_flag = true;
	regex_t		reg;
	regmatch_t	match[MAX_MATCH];
	char		err_msg[MAX_BUF];
	char		buf[MAX_BUF];

	for ( ; f1; f1 = f1->next) {
		snprintf( buf, _number_(buf), "^%s$", f1->msg );
		const int ret_regcomp = regcomp( &reg, buf, REG_EXTENDED );
		if (ret_regcomp) {
			regerror( ret_regcomp, &reg, err_msg, _number_(err_msg) );
			fprintf(stderr, "%d: ERROR in regcomp() :%s\n", f1->num, err_msg );
			continue;
		}

		f1->hit = false;
		for ( Line* ptr = f2; ptr; ptr = ptr->next) {
			if (ptr->hit) {
				continue;
			}
			const int ret_regexec = regexec( &reg, ptr->msg, _number_(match), match, 0 );
			if (0 == ret_regexec) {
				f1->hit = true;
				ptr->hit = true;
				break;
			}
		}
		regfree( &reg );

		if (!f1->hit) {
			printf("%d<%s", f1->num, f1->msg );
			match_flag = false;
		}
	}
	for ( ; f2; f2 = f2->next) {
		if (!f2->hit) {
			printf("%d>%s", f2->num, f2->msg );
			match_flag = false;
		}
	}
	return match_flag;
}


Line* const fread_file( FILE* const fp )
{
	char		buf[MAX_BUF];
	int			line_num = 0;
	Line		init = { false, 0, NULL, NULL };
	Line*		ptr = &init;

	while (!feof(fp)) {
		buf[0] = '\0';
		fgets( buf, _number_(buf), fp );
		line_num++;
		if ('\0' == buf[0]) {
			break;
		}

		ptr->next = new Line;
		ptr->next->hit = false;
		const size_t	line_len = strlen(buf) + 1;
		ptr->next->num = line_num;
		ptr->next->msg = new char[line_len];
		memcpy( ptr->next->msg, buf, line_len );
		ptr->next->next = NULL;

		ptr = ptr->next;
	}
	return init.next;
}


int main( __unused int argc, __unused const char* argv[], __unused const char* env[] )
{
	if ((argc < 3) || (3 < argc)) {
		fprintf(stderr, "Too few/many argment.\n" );
		return -1;
	}

	FILE* const fp1 = fopen( argv[1], "r" );
	FILE* const fp2 = fopen( argv[2], "r" );

	Line* const	f1 = fread_file( fp1 );
	Line* const	f2 = fread_file( fp2 );

	fclose( fp1 );
	fclose( fp2 );

	const bool	ret = diffregex( f1, f2 );

	f1->free( f1 );
	f2->free( f2 );

	return ret ? 0 : 1;
}
/* [ End of File ] */