/*
*	`create' create files of specified size
*	usage: usage: create [-s size] file ...
*	where the format of size is shown bellow
*	using example:
*		123		# 123 Byte
*		123K	# 123 Kiro Byte
*		123M	# 123 Mega Byte
*		123G	# 123 Giga Byte
*	Lower case is OK for K,M,G.
*	If size if not given, 0 is assumed.
*	If the files already exist, `create' will
*	exit with error message.
*	coded by: Kenji Arisawa
*/
#include <u.h>
#include <libc.h>

char *usage = "usage: create [-s size] file ...";

vlong getsize(char *s)
{
	vlong size;
	size = atoll(s);
	while(strchr("0123456789",*s))
		s++;
	if(strchr("Gg",*s))
		size *= 1024*1024*1024;
	else if(strchr("Mm", *s))
		size *= 1024*1024;
	else if(strchr("Kk", *s))
		size *= 1024;
	return size;
}

void main(int argc, char *argv[])
{	vlong size;
	int fd;
	size = 0;
	ARGBEGIN{
	case 's':
		size=getsize(ARGF());
		break;
	default:
		sysfatal(usage);
	}ARGEND
	
	while(*argv){
		if(open(*argv, OREAD) > 0){
			fprint(2, "file already exist: %s\n", *argv);
			goto next;
		}
		fd = create(*argv, ORDWR, 0666);
		if(fd < 0)
			fprint(2, "cannot create %s\n", *argv);
		else	if(size){
			seek(fd, size, 0);
			write(fd,"", 0);
		}
		next:
		close(fd);
		argv++;
	}
}