#include <fcntl.h>
#include <sys/types.h>
#include <sys/dkio.h>
#include <sys/vtoc.h>
#include <errno.h>

#include <stdio.h>
#include <unistd.h>


void usage(){
	puts("Usage: ");
	puts("  getvtoc /dev/name [block_offset [-i]]");
	puts("     -i means 'ignore bad magic field and print anyway'");
	puts("    NOTE: standard solaris p devs tend to need an offset of 1");
	
}

int main(int argc, char *argv[]){
	int  fd, pc;
	struct vtoc *label;
	int offset;
	char buffer[1024];

	if(argc<2){
		puts("Need name of  device!");
		usage();
		exit(1);
	}
	if(argc==3){
		offset=atoi(argv[2]);
		printf("using block offset of %d blocks\n",offset);
	}
	fd=open(argv[1],O_RDONLY);

	if(fd==-1){
		perror("could not open device");
		exit(errno);
	}

	if(offset>0){
		lseek(fd,offset*512, SEEK_SET);
	}
	if(read(fd,buffer,1024) !=1024){
		perror("err reading initial 1k");
		exit(errno);
	}
	label=(struct vtoc*)buffer;

	if(label->v_sanity != VTOC_SANE){
		fprintf(stderr,"ERROR: No VTOC MAGIC. Bad VTOC\n");
		if(offset!=1){
			fprintf(stderr,"(maybe you should try offset=1)");
		}
		if(argc <4)
			return 1;
	}
	puts("here is the vtoc we got");

	printf("volume name %s\n",label->v_volume);
	for(pc=0;pc<10;pc++){
		printf("%d: startblock %d, size %d, type %d\n",
		pc,
			label->v_part[pc].p_start,
			label->v_part[pc].p_size,
			label->v_part[pc].p_tag);
	}

	return 0;
}