int main(int argc, char *argv[])
{
int ifdes, fdes;
int err_value;
char input_fname[20];
char *buf;
ssize_t nread;
struct pfs_stat mystat;
int cache_hit;
// Initialize the client
initialize(argc, argv);
// the command line arguments include an input filename
if (argc < 2)
{
printf("usage: a.out <input filename>\n");
exit(0);
}
strcpy(input_fname, argv[1]);
ifdes = open(input_fname, O_RDONLY);
buf = (char *)malloc(4*ONEKB);
nread = pread(ifdes, (void *)buf, 3*ONEKB,8*ONEKB);
// All the clients open the pfs file
fdes = pfs_open("pfs_file1", 'w');
if(fdes < 0)
{
printf("Error opening file\n");
exit(0);
}
//At client 3: print the file metadata
pfs_fstat(fdes, &mystat);
printf("File Metadata:\n");
printf("Time of creation: %s\n", ctime(&(mystat.pst_ctime)));
printf("Time of last modification: %s\n", ctime(&(mystat.pst_mtime)));
printf("File Size: %d\n", mystat.pst_size);
//Write the next 3 kbytes of data from the input file onto pfs_file
err_value = pfs_write(fdes, (void *)buf, 3*ONEKB, 8*ONEKB, &cache_hit);
printf("Wrote %d bytes to the file\n", err_value);
err_value = pfs_read(fdes, (void *)buf, 2*ONEKB, ONEKB, &cache_hit);
printf("Read %d bytes of data from the file\n", err_value);
printf("%s\n",buf);
pfs_close(fdes);
pfs_delete("pfs_file1");
free(buf);
close(ifdes);
return 0;
}
int flusher()
{
int i;
for(i=0;i<CLIENT_CACHE_LINES;i++)
if(metacache[i][0] == 2) //changed or dirty
{//flush(cache[i]);
char buf[ONEKB];
int ofi = metacache[i][3];
OpenFile* of = openfiles[ofi];
int cachehit;
pfs_write(of->fd, buf, ONEKB, metacache[i][1]*ONEKB, &cachehit);
}
// 2. Flusher Thread: The job of the flusher thread is to periodically (every 30 seconds) flush
// all the dirty blocks (modified blocks) back to the appropriate file servers.
// Note that you will have to implement a hashing scheme to map and look up the file blocks onto
// the cache.
return 0;
}
int main2(int argc, char *argv[])
{
argc=2;argv[1]="1";
initialize(argc,argv);
int fdes;
int err_value;
off_t myoff;
char *buf;
int cache_hit, go_on;
ssize_t nread;
// Open the file in the write mode
fdes = pfs_open("pfs_file1", "w");
if(fdes < 0)
{
printf("Error opening file\n");
exit(0);
}
//Do overlapping writes onto the same pfs_file from multiple clients
buf = (char*)malloc(ONEKB);
while(go_on)
{
printf("Enter text to be written to the file\ntext>");
scanf("%[^\n]s", buf);
printf("Enter the offset:");
scanf("%d", &myoff);
err_value = pfs_write(fdes, (void *)buf, strlen(buf), myoff, &cache_hit);
printf("Wrote %d bytes to the file\n", err_value);
printf("Enter more text? (1 or 0):");
scanf("%d", &go_on);
}
free(buf);
pfs_close(fdes);
}
