#include <stdio.h>
#include <unistd.h>
#include <sys/file.h>
#include "fakedisc.h"

int createdisc(char *name, long int numblocks)
{ block b;
  int discnum,x;
  long int i;
  for (i=0; i<512; i++) b[i]=0;
  discnum=open(name, O_RDWR|O_CREAT, 0600);
  if (discnum<0)
  { fprintf(stderr,"Create failed for \"%s\"\n",name);
    return (0); }
  for (i=0; i<numblocks; i++)
  { x=write(discnum,b,512);
    if (x<512)
    { fprintf(stderr,"Failed to create block %d of \"%s\"\n",i,name);
      return (0); } }
  close(discnum);
  return (1); }

int mountdisc(char *name)
{ int discnum;
  discnum=open(name,O_RDWR);
  if (discnum<0)
  { fprintf(stderr,"Failed to open \"%s\"\n",name);
    return (-1); }
  return(discnum); }
  
long int discsize(int discnum)
{ long int sz=lseek(discnum,0,2);
  return (sz/512); }

void dismountdisc(int discnum)
{ close(discnum); }

int writeblock(int discnum, long int blocknum, void *b)
{ long int x;
  x=lseek(discnum,blocknum*512,L_SET);
  if (x<0)
  { fprintf(stderr,"\nFailed to access block %d of disc\n",blocknum);
    return (0); }
  x=write(discnum,b,512);
  if (x<512)
  { fprintf(stderr,"\nFailed to write block %d of disc\n",blocknum);
    return (0); }
  return (1); }
  
int readblock(int discnum, long int blocknum, void *b)
{ long int x;
  x=lseek(discnum,blocknum*512,L_SET);
  if (x<0)
  { fprintf(stderr,"\nFailed to access block %d of disc\n",blocknum);
    return (0); }
  x=read(discnum,b,512);
  if (x<512)
  { fprintf(stderr,"\nFailed to read block %d of disc\n",blocknum);
    return (0); }
  return (1); }