/* This fixes up a filesystem which has bad data in the last block
 * of the file out beyond eof. This confuses some applications.
 *
 * Copyright Stephen Lord 2002, All Rights Reserved.
 */

#include <fcntl.h>
#include <unistd.h>
#include <sys/mman.h>
#include <sys/stat.h>
#include <stdio.h>
#include <ftw.h>
#include <signal.h>



int	verbose = 0, readonly = 0;
int	filecount, fixedcount;

int	checker(
	const char *file,
	const struct stat *st,
	int flag)
{
	int fd, i, n;
	char *ptr, *ptr2;
	off_t	offset;

	if (flag != FTW_F)
		return 0;

	if (st->st_size % 4096==0) {
		return (0);
	}

	fd = open(file,O_RDWR);
	if(fd<0) {
		return(0);
	}
	filecount++;
	offset = 4096 - st->st_size % 4096;

	ptr = mmap(NULL,st->st_size,PROT_READ|PROT_WRITE,MAP_SHARED,fd,0);
	ptr2 = ptr + st->st_size;
	for (i = 0; i < offset; i++, ptr2++) {
		if (*ptr2 != 0) {
			if (verbose)
				printf("%s\n", file);
			if (!readonly)
				memset(ptr + st->st_size, 0, offset);
			fixedcount++;
			if ((fixedcount % 100) == 0)
				putchar('+');
			break;
		}
	}
	munmap(ptr, st->st_size);
	close(fd);
	if ((filecount % 100) == 0)
		putchar('.');
	return(0);
}
 
void	catcher(int sig)
{
	printf("\nInterrupted: %d files scanned %d files fixed\n",
		filecount, fixedcount);
	exit(0);
}

int main(int argc, char **argv)
{
	setbuf(stdout, NULL);
	signal(SIGINT, catcher);

	ftw(argv[1], checker, 20);

	printf("%d files scanned %d files fixed\n", 
		filecount, fixedcount);
	exit (0);
}